Publications by authors named "Eric L Brown"

59 Publications

N95 respirator reuse, decontamination methods, and microbial burden: A randomized controlled trial.

Am J Otolaryngol 2021 Mar 31;42(5):103017. Epub 2021 Mar 31.

Department of Otorhinolaryngology-Head and Neck Surgery, McGovern Medical School, Houston, TX, USA; Center for Immunology and Autoimmune Diseases, Institute of Molecular Medicine, McGovern Medical School at The University of Texas Health Science Center, Houston, TX, USA. Electronic address:

Purpose: To evaluate the effectiveness and ease of N95 respirator decontamination methods in a clinic setting and to identify the extent of microbial colonization on respirators associated with reuse.

Methods: In a prospective fashion, N95 respirators (n = 15) were randomized to a decontamination process (time, dry heat, or ultraviolet C light [UVC]) in outpatient clinics. Each respirator was re-used up to 5 separate clinic sessions. Swabs on each respirator for SARS-CoV-2, bacteria, and fungi were obtained before clinic, after clinic and post-treatment. Mask integrity was checked after each treatment (n = 68). Statistical analyses were performed to determine factors for positive samples.

Results: All three decontamination processes reduced bacteria counts similarly. On multivariate mixed model analysis, there were an additional 8.1 colonies of bacteria (95% CI 5.7 to 10.5; p < 0.01) on the inside compared to the outside surface of the respirators. Treatment resulted in a decrease of bacterial load by 8.6 colonies (95% CI -11.6 to -5.5; p < 0.01). Although no decontamination treatment affected the respirator filtration efficiency, heat treatments were associated with the breakdown of thermoplastic elastomer straps. Contamination with fungal and SARS-CoV-2 viral particles were minimal to non-existent.

Conclusions: Time, heat and UVC all reduced bacterial load on reused N95 respirators. Fungal contamination was minimal. Heat could permanently damage some elastic straps making the respirators nonfunctional. Given its effectiveness against microbes, lack of damage to re-treated respirators and logistical ease, UVC represents an optimal decontamination method for individual N95 respirators when reuse is necessary.
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http://dx.doi.org/10.1016/j.amjoto.2021.103017DOI Listing
March 2021

The Epidemiology of Meningitis in Infants under 90 Days of Age in a Large Pediatric Hospital.

Microorganisms 2021 Mar 4;9(3). Epub 2021 Mar 4.

Department of Pediatrics, Section of Pediatric Tropical Medicine, William T. Shearer Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX 77030, USA.

Background: Meningitis is associated with substantial morbidity and mortality, particularly in the first three months of life.

Methods: We conducted a retrospective review of patients <90 days of age with meningitis at Texas Children's Hospital from 2010-2017. Cases were confirmed using the National Healthcare Safety Network (NHSN) definition of meningitis.

Results: Among 694 infants with meningitis, the most common etiology was viral ( = 351; 51%), primarily caused by enterovirus ( = 332; 95%). A quarter of cases were caused by bacterial infections ( = 190; 27%). The most common cause of bacterial meningitis was group B (GBS, = 60; 32%), followed by Gram-negative rods other than ( = 40; 21%), and ( = 37; 19%). The majority of Gram-negative organisms (63%) were resistant to ampicillin, and nearly one-fourth of Gram-negative rods (23%) other than and 2 (6%) isolates were resistant to third-generation cephalosporins. Significant risk factors for bacterial meningitis were early preterm birth and the Black race.

Conclusions: Enteroviruses most commonly caused viral meningitis in infants; GBS was the most common bacterial cause despite universal screening and intrapartum prophylaxis. The emergence of MRSA and resistance to third-generation cephalosporins in Gram-negative bacterial meningitis challenges the options for empirical antimicrobial therapy.
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http://dx.doi.org/10.3390/microorganisms9030526DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7999219PMC
March 2021

Original Antigenic Sin: the Downside of Immunological Memory and Implications for COVID-19.

mSphere 2021 03 10;6(2). Epub 2021 Mar 10.

Center for Infectious Disease, Division of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas Health Science Center, Houston, Texas, USA.

The concept of original antigenic sin (OAS) was put forth many years ago to explain how humoral memory responses generated against one set of antigens can affect the nature of antibody responses elicited to challenge infections or vaccinations containing a similar but not identical array of antigens. Here, we highlight the link between OAS and the germinal center reaction (GCR), a process unique to activated B cells undergoing somatic hypermutation and class switch recombination. It is the powerful response of activated memory B cells and the accompanying GCR that establish the foundations of OAS. We apply these concepts to the current COVID-19 pandemic and put forth several possible scenarios whereby OAS may result in either beneficial or harmful outcomes depending, hypothetically, on prior exposure to antigens shared between SARS-CoV-2 and seasonal human coronaviruses (hCoVs) that include betacoronaviruses (e.g., HCoV-OC43 and HCoV-HKU1) and alphacoronaviruses (e.g., HCoV-NL63 and HCoV-HKU1) (E. M. Anderson, E. C. Goodwin, A. Verma, C. P. Arevalo, et al., medRxiv, 2020, https://doi.org/10.1101/2020.11.06.20227215; S. M. Kissler, C. Tedijanto, E. Goldstein, Y. H. Grad, and M. Lipsitch, Science 368:860-868, 2020, https://doi.org/10.1126/science.abb5793).
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http://dx.doi.org/10.1128/mSphere.00056-21DOI Listing
March 2021

An assessment of outpatient clinic room ventilation systems and possible relationship to disease transmission.

Am J Infect Control 2021 06 21;49(6):808-812. Epub 2021 Jan 21.

The University of Texas Health Science Center at Houston, Houston, TX; School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX.

Background: With healthcare shifting to the outpatient setting, this study examined whether outpatient clinics operating in business occupancy settings were conducting procedures in rooms with ventilation rates above, at, or below thresholds defined in the American National Standards Institute/American Society of Heating, Refrigerating and Air-Conditioning Engineers/American Society for Health Care Engineering Standard 170 for Ventilation in Health Care Facilities and whether lower ventilation rates and building characteristics increase the risk of disease transmission.

Methods: Ventilation rates were measured in 105 outpatient clinic rooms categorized by services rendered. Building characteristics were evaluated as determinants of ventilation rates, and risk of disease transmission was estimated using the Gammaitoni-Nucci model.

Results: When compared to Standard 170, 10% of clinic rooms assessed did not meet the minimum requirement for general exam rooms, 39% did not meet the requirement for treatment rooms, 83% did not meet the requirement for aerosol-generating procedures, and 88% did not meet the requirement for procedure rooms or minor surgical procedures.

Conclusions: Lower than standard air changes per hour were observed and could lead to an increased risk of spread of diseases when conducting advanced procedures and evaluating persons of interest for emerging infectious diseases. These findings are pertinent during the SARS-CoV-2 pandemic, as working guidelines are established for the healthcare community.
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http://dx.doi.org/10.1016/j.ajic.2021.01.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8052498PMC
June 2021

Impact of Diabetes on the Gut and Salivary IgA Microbiomes.

Infect Immun 2020 11 16;88(12). Epub 2020 Nov 16.

Center for Infectious Disease, Division of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas Health Science Center, Houston, Texas, USA.

Mucosal surfaces like those present in the lung, gut, and mouth interface with distinct external environments. These mucosal gateways are not only portals of entry for potential pathogens but also homes to microbial communities that impact host health. Secretory immunoglobulin A (SIgA) is the single most abundant acquired immune component secreted onto mucosal surfaces and, via the process of immune exclusion, shapes the architecture of these microbiomes. Not all microorganisms at mucosal surfaces are targeted by SIgA; therefore, a better understanding of the SIgA-coated fraction may identify the microbial constituents that stimulate host immune responses in the context of health and disease. Chronic diseases like type 2 diabetes are associated with altered microbial communities (dysbiosis) that in turn affect immune-mediated homeostasis. 16S rRNA gene sequencing of SIgA-coated/uncoated bacteria (IgA-Biome) was conducted on stool and saliva samples of normoglycemic participants and individuals with prediabetes or diabetes ( = 8/group). These analyses demonstrated shifts in relative abundance in the IgA-Biome profiles between normoglycemic, prediabetic, or diabetic samples distinct from that of the overall microbiome. Differences in IgA-Biome alpha diversity were apparent for both stool and saliva, while overarching bacterial community differences (beta diversity) were also observed in saliva. These data suggest that IgA-Biome analyses can be used to identify novel microbial signatures associated with diabetes and support the need for further studies exploring these communities. Ultimately, an understanding of the IgA-Biome may promote the development of novel strategies to restructure the microbiome as a means of preventing or treating diseases associated with dysbiosis at mucosal surfaces.
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http://dx.doi.org/10.1128/IAI.00301-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7671898PMC
November 2020

Characterization of peripheral blood mononuclear cells gene expression profiles of pediatric Staphylococcus aureus persistent and non-carriers using a targeted assay.

Microbes Infect 2020 Nov - Dec;22(10):540-549. Epub 2020 Aug 3.

Division of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas Health Science Center, Houston, TX, USA. Electronic address:

Defects in innate immunity affect many different physiologic systems and several studies of patients with primary immunodeficiency disorders demonstrated the importance of innate immune system components in disease prevention or colonization of bacterial pathogens. To assess the role of the innate immune system on nasal colonization with Staphylococcus aureus, innate immune responses in pediatric S. aureus nasal persistent carriers (n = 14) and non-carriers (n = 15) were profiled by analyzing co-clustered gene sets (modules). We stimulated previously frozen peripheral blood mononuclear cells (PBMCs) from these subjects with i) a panel of TLR ligands, ii) live S. aureus (either a mixture of strains or stimulation with respective carriage isolates), or iii) heat-killed S. aureus. We found no difference in responses between carriers and non-carriers when PBMCs were stimulated with a panel of TLR ligands. However, PBMC gene expression profiles differed between persistent and non-S. aureus carriers following stimulation with either live or dead S. aureus. These observations suggest that individuals susceptible to persistent carriage with S. aureus may possess differences in their live/dead bacteria recognition pathway and that innate pathway signaling is different between persistent and non-carriers of S. aureus.
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http://dx.doi.org/10.1016/j.micinf.2020.07.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7722038PMC
August 2020

Time trends and predictors of survival in surgically resected early-stage non-small cell lung cancer patients.

J Surg Oncol 2020 Sep 30;122(3):495-505. Epub 2020 Apr 30.

Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas.

Background: The improvement in the management of lung cancer have the potential to improve survival in patients undergoing resection for early-stage (stage I and II) non-small cell lung cancer (NSCLC), but few studies have evaluated time trends and identified predictors of overall survival (OS).

Methods: We identified surgically resected early-stage NSCLC between 1998 and 2016. The 3-year OS (1998-2014) and 5-year OS (1998-2012) rates were calculated for each year. Joinpoint regression was used to calculate annual percentage changes (APC) and to test time trends in OS. Multivariable Cox regression was used to identify predictors of OS.

Results: There was a significant upward trend in the 3-year (1998, 56%; 2014, 83%; APC = 1.8) and 5-year (1998, 47%; 2012, 76%; APC = 3.1) OS. Older age; male sex; history of diabetes, coronary artery disease, and chronic obstructive pulmonary disease; high ASA score; smoking pack-years; high-grade tumor; pneumonectomy; thoracotomy; neoadjuvant therapy; nodal disease; and positive tumor margin were predictors of poor OS.

Conclusion: The upward time trend in OS suggests that improved staging, patient selection, and management have conferred a survival benefit in early-stage NSCLC patients. The prediction model of OS could be used to refine selection criteria for resection and improve survival outcomes.
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http://dx.doi.org/10.1002/jso.25966DOI Listing
September 2020

Time Trends of Perioperative Outcomes in Early Stage Non-Small Cell Lung Cancer Resection Patients.

Ann Thorac Surg 2020 02 17;109(2):404-411. Epub 2019 Sep 17.

Department of Thoracic and Cardiovascular Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address:

Background: Advances in perioperative and operative management hold great promise for improving perioperative outcomes in patients undergoing resection for early stage non-small cell lung cancer (NSCLC). The objective of this study was to evaluate time trends in the incidence of perioperative outcomes and to identify predictors of pulmonary complication in early stage NSCLC resection patients.

Methods: An institutional database was reviewed to identify patients with primary, clinical stage I and II NSCLC who underwent resection from 1998 to 2016. Rates of perioperative pulmonary complication, pneumonia, and cardiovascular complication; and 30-day and 90-day mortality were calculated for each year. Joinpoint regression was used to calculate annual percentage change (APC) and to evaluate time trends in rates of these outcomes. Multivariable logistic regression was conducted to identify predictors of pulmonary complication.

Results: Of the 3045 patients identified, 80% had stage I and 20% had stage II NSCLC. From 1998 to 2016, there was no trend in the rate of pulmonary complication, but there was a significant downward trend in the rates of pneumonia (APC -3.7), cardiovascular complication (APC -3.5), 30-day mortality (APC -9.8), and 90-mortality (APC -7.4). Older age, male sex, smoking status, percentage of predicted forced expiratory volume in 1 second and percentage of diffusion capacity of lung for carbon monoxide, and intraoperative blood transfusion were identified as predictors of pulmonary complication.

Conclusions: Decrease in the rates of perioperative outcomes parallels improvements in patient selection and perioperative management of early stage NSCLC resection patients. Predictors of pulmonary complication could be used to improve selection criteria for surgery and to reduce the incidence of pulmonary complication in these patients.
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http://dx.doi.org/10.1016/j.athoracsur.2019.08.018DOI Listing
February 2020

Continuing evidence of Chagas disease along the Texas-Mexico border.

PLoS Negl Trop Dis 2018 11 14;12(11):e0006899. Epub 2018 Nov 14.

Department of Pediatric Tropical Medicine, Baylor College of Medicine, Houston, TX, United States of America.

Background: Chagas disease is a chronic parasitic infection that progresses to dilated cardiomyopathy in 30% of human cases. Public health efforts target diagnosing asymptomatic cases, as therapeutic efficacy diminishes as irreversible tissue damage progresses. Physician diagnosis of Chagas disease cases in the United States is low, partially due to lack of awareness of the potential burden in the United States.

Methodology/principal Findings: The current study tested a patient cohort of 1,196 Starr County, Texas residents using the Hemagen Chagas ELISA Kit as a preliminary screening assay. Samples testing positive using the Hemagen test were subjected to additional confirmatory tests. Two patients (0.17%) without previous Chagas disease diagnosis were identified; both had evidence of acquiring disease in the United States or along the Texas-Mexico border.

Conclusions/significance: The Texas-Mexico border is a foci of Chagas disease human cases, with a local disease burden potentially twice the national estimate of Hispanic populations. It is imperative that physicians consider persons with residential histories along the Texas-Mexico border for Chagas disease testing.
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http://dx.doi.org/10.1371/journal.pntd.0006899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6261633PMC
November 2018

Covalent vaccination with Trypanosoma cruzi Tc24 induces catalytic antibody production.

Parasite Immunol 2018 Nov 24;40(11):e12585. Epub 2018 Sep 24.

Center for Infectious Disease, The University of Texas School of Public Health, Houston, Texas.

Trypanosoma cruzi 24 (Tc24) is a recently described B-cell superantigen (BC-SAg) expressed by all developmental stages of T. cruzi, the causative agent of Chagas disease. BC-SAgs are immunoevasins that interfere with the catalytic response available to a subset of natural antibodies comprising the preimmune (innate) repertoire. Electrophilic modifications of BC-SAgs facilitate the formation of highly energetic covalent reactions favouring B-cell differentiation instead of B-cell downregulation. Therefore, the aim of this study was to convert the inhibitory signals delivered to B-cells with specificity for Tc24 into activating signals after conjugating electrophilic phosphonate groups to recombinant Tc24 (eTc24). Covalent immunization with eTc24 increased the binding affinity between eTc24 and naturally nucleophilic immunoglobulins with specificity for this BC-SAg. Flow cytometric analyses demonstrated that eTc24 but not Tc24 or other electrophilically modified control proteins bound Tc24-specific IgM B-cells covalently. In addition, immunization of mice with eTc24 adjuvanted with ISA720 induced the production of catalytic responses specific for Tc24 compared to the abrogation of this response in mice immunized with Tc24/ISA720. eTc24-immunized mice also produced IgMs that bound recombinant Tc24 compared to the binding observed for IgMs purified from non eTc24-immunized controls. These data suggest that eTc24 immunization overrides the immunosuppressive properties of this BC-SAg.
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http://dx.doi.org/10.1111/pim.12585DOI Listing
November 2018

Identification of White-tailed Deer ( Odocoileus virginianus) as a Novel Reservoir Species for Trypanosoma cruzi in Texas, USA.

J Wildl Dis 2018 10 11;54(4):814-818. Epub 2018 Jun 11.

1 Baylor College of Medicine, National School of Tropical Medicine, Section of Tropical Medicine, 1102 Bates Ave., Houston, Texas 77030, USA.

Chagas disease, a vector-borne parasitic infection caused by Trypanosoma cruzi, represents a significant source of morbidity and mortality in the Americas. Mammalian reservoir species play a large role in propagating the sylvatic transmission cycle of this disease, and this cycle can spill over, resulting in human infections. Our understanding of the wildlife species implicated in propagating this transmission cycle is incomplete. We investigated white-tailed deer ( Odocoileus virginianus) as a potential novel reservoir for this parasite. Only one of the 314 hunter-harvested deer hearts collected across Texas, was PCR-positive (0.3%) for T. cruzi. This finding has potential implications for deer hunters, because it indicates that there might be a risk of blood-borne transmission during the field-dressing process. Hunters should be strongly encouraged to wear gloves and other personal protective equipment when handling carcasses to prevent exposure to infected blood.
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http://dx.doi.org/10.7589/2017-09-223DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6211790PMC
October 2018

Range Expansion and the Origin of USA300 North American Epidemic Methicillin-Resistant .

mBio 2018 01 2;9(1). Epub 2018 Jan 2.

Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi, USA

The USA300 North American epidemic (USA300-NAE) clone of methicillin-resistant has caused a wave of severe skin and soft tissue infections in the United States since it emerged in the early 2000s, but its geographic origin is obscure. Here we use the population genomic signatures expected from the serial founder effects of a geographic range expansion to infer the origin of USA300-NAE and identify polymorphisms associated with its spread. Genome sequences from 357 isolates from 22 U.S. states and territories and seven other countries are compared. We observe two significant signatures of range expansion, including decreases in genetic diversity and increases in derived allele frequency with geographic distance from the Pennsylvania region. These signatures account for approximately half of the core nucleotide variation of this clone, occur genome wide, and are robust to heterogeneity in temporal sampling of isolates, human population density, and recombination detection methods. The potential for positive selection of a fluoroquinolone resistance allele and several intergenic regions, along with a 2.4 times higher recombination rate in a resistant subclade, is noted. These results are the first to show a pattern of genetic variation that is consistent with a range expansion of an epidemic bacterial clone, and they highlight a rarely considered but potentially common mechanism by which genetic drift may profoundly influence bacterial genetic variation. The process of geographic spread of an origin population by a series of smaller populations can result in distinctive patterns of genetic variation. We detect these patterns for the first time with an epidemic bacterial clone and use them to uncover the clone's geographic origin and variants associated with its spread. We study the USA300 clone of methicillin-resistant , which was first noticed in the early 2000s and subsequently became the leading cause of skin and soft tissue infections in the United States. The eastern United States is the most likely origin of epidemic USA300. Relatively few variants, which include an antibiotic resistance mutation, have persisted during this clone's spread. Our study suggests that an early chapter in the genetic history of this epidemic bacterial clone was greatly influenced by random subsampling of isolates during the clone's geographic spread.
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http://dx.doi.org/10.1128/mBio.02016-17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5750399PMC
January 2018

A Community-Based Study of Staphylococcus aureus Nasal Colonization and Molecular Characterization Among Men Who Have Sex with Men.

LGBT Health 2017 10 15;4(5):345-351. Epub 2017 Sep 15.

1 Department of Epidemiology, Human Genetics, and Environmental Sciences, Center for Infectious Diseases, University of Texas Health Science Center , Houston, Texas.

Purpose: The aims of this cross-sectional study were to determine the prevalence of Staphylococcus aureus nasal colonization, evaluate community-related behavioral risk factors, and utilize staphylococcal protein A (spa) typing for epidemiological surveillance among community-based men who have sex with men from the National HIV Behavioral Surveillance System in Houston, Texas.

Methods: Descriptive methods and logistic analyses were used to determine associations with nasal colonization.

Results: The prevalence of S. aureus colonization was 29.7%; of these, 3.0% were colonized with methicillin-resistant S. aureus. Logistic analyses revealed that anal intercourse practices were associated with colonization (P < 0.05). A diverse population of 38 spa types was identified.

Conclusion: Our findings suggest that an association among preferential sex practices, condom use, and S. aureus colonization exists and should be investigated further.
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http://dx.doi.org/10.1089/lgbt.2017.0016DOI Listing
October 2017

A phase II clinical study to assess the feasibility of self and partner anal examinations to detect anal canal abnormalities including anal cancer.

Sex Transm Infect 2018 03 23;94(2):124-130. Epub 2017 Aug 23.

Department of Internal Medicine, Baylor College of Medicine, Houston, Texas, USA.

Objective: Anal cancer is a common cancer among men who have sex with men (MSM); however, there is no standard screening protocol for anal cancer. We conducted a phase II clinical trial to assess the feasibility of teaching MSM to recognise palpable masses in the anal canal which is a common sign of anal cancer in men.

Methods: A clinician skilled in performing digital anorectal examinations (DARE) used a pelvic manikin to train 200 MSM, aged 27-78 years, how to do a self-anal examination (SAE) for singles or a partner anal examination (PAE) for couples. The clinician then performed a DARE without immediately disclosing results, after which the man or couple performed an SAE or PAE, respectively. Percentage agreement with the clinician DARE in addition to sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for the SAE, PAE and overall.

Results: Men had a median age of 52 years, 42.5% were African American and 60.5% were HIV positive. DARE detected abnormalities in 12 men while the men's SAE/PAEs detected 9 of these. A total of 93.0% of men classified the health of their anal canal correctly (95% CI 89.5 to 96.5). Overall percentage agreement, sensitivity and specificity were 93.0%, 75.0% and 94.2%, respectively, while PPV and NPV were 45.0% and 98.3%, respectively. The six men who detected the abnormality had nodules/masses ≥3 mm in size. More than half of men (60.5%) reported never checking their anus for an abnormality; however, after performing an SAE/PAE, 93.0% said they would repeat it in the future.

Conclusion: These results suggest that tumours of ≥3 mm may be detectable by self or partner palpation among MSM and encourage further investigation given literature suggesting a high cure rate for anal cancer tumours ≤10 mm.
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http://dx.doi.org/10.1136/sextrans-2017-053283DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6173609PMC
March 2018

The effect of sustained virological response on the risk of extrahepatic manifestations of hepatitis C virus infection.

Gut 2018 03 20;67(3):553-561. Epub 2017 Jun 20.

Department of Epidemiology, Human Genetics, and Environmental Sciences, The University of Texas School of Public Health, Houston, Texas, USA.

Background And Aim: Chronic HCV infection is associated with several extrahepatic manifestations (EHMs). Data on the effect of sustained virological response (SVR) on the risk of EHMs are limited.

Methods: We conducted a retrospective cohort study using data of patients from the US Veterans Affairs HCV Clinical Case Registry who had a positive HCV RNA test (10/1999-08/2009). Patients receiving interferon-based antiviral therapy (AVT) were identified. SVR was defined as negative HCV RNA at least 12 weeks after end of AVT. Risks of eight incident EHMs were evaluated in Cox regression models.

Results: Of the 160 875 HCV-infected veterans, 31 143 (19.4%) received AVT, of whom 10 575 (33.9%) experienced SVR. EHM risk was reduced in the SVR group compared with untreated patients for mixed cryoglobulinaemia (adjusted HR (aHR)=0.61; 95% CI 0.39 to 0.94), glomerulonephritis (aHR=0.62; 95% CI 0.48 to 0.79), porphyria cutanea tarda (PCT) (aHR=0.41; 95% CI 0.20 to 0.83), non-Hodgkin's lymphoma (NHL) (aHR=0.64; 95% CI 0.43 to 0.95), diabetes (aHR=0.82; 95% CI 0.76 to 0.88) and stroke (aHR=0.84; 95% CI 0.74 to 0.94), but not for lichen planus (aHR=1.11; 95% CI 0.78 to 1.56) or coronary heart disease (aHR=1.12; 95% CI 0.81 to 1.56). Risk reductions were also observed when patients with SVR were compared with treated patients without SVR for mixed cryoglobulinaemia, glomerulonephritis, PCT and diabetes. Significant reductions in the magnitude of aHRs towards the null with increasing time to initiation of AVT after HCV diagnosis were observed for glomerulonephritis, NHL and stroke.

Conclusions: Risks of several EHMs of HCV infection are reduced after AVT with SVR. However, early initiation of AVT may be required to reduce the risk of glomerulonephritis, NHL and stroke.
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http://dx.doi.org/10.1136/gutjnl-2017-313983DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6292199PMC
March 2018

Mutations to Cysteine Residues in the Trypanosoma cruzi B-Cell Superantigen Tc24 Diminish Susceptibility to IgM-Mediated Hydrolysis.

J Parasitol 2017 10 5;103(5):579-583. Epub 2017 Jun 5.

Baylor College of Medicine, National School of Tropical Medicine, Section of Tropical Medicine, Houston, Texas 77030.

B-cell superantigens (BC-SAgs) are immunoevasins that have evolved in response to innate catalytic IgM antibodies; germ-line encoded immunoglobulins present in the preimmune repertoire independent of prior antigen exposure. Catalysis is the result of a 2-step process that involves first the formation of a non-covalent bond between the BC-SAg and the immunoglobulin followed by covalent bond formation at the catalytic site resulting in target hydrolysis. Tc24 is a recently described Trypanosoma cruzi BC-SAg hypothesized to play a role in evading the humoral response early in the infection period. We previously demonstrated that exposure to Tc24 following immunization or infection resulted in the depletion of the catalytic IgM response, leaving a gap in the catalytic IgM repertoire. The present report compares the BC-SAg properties of wild-type Tc24 (Tc24-WT) to that of 2 recombinant Tc24 isoforms: Tc24-C2 (Cys to Ser mutations in the 2 most-proximal Cys residues) and Tc24-C4 (Cys to Ser mutations in all 4 Cys residues present). BC-SAg activity was assessed by immunizing mice with the respective isoforms and examining the ability of IgM purified from the respective groups to hydrolyze the 3 Tc24 isoforms. In addition, the ability of IgM purified from naive mice to hydrolyze the Tc24 isoforms was also assessed. Immunization with Tc24-WT, Tc24-C2, or Tc24-C4 resulted in loss of IgM-mediated hydrolysis of Tc24-WT. However, the ability of IgM purified from naive mice (previously shown to hydrolyze Tc24-WT) was less effective in hydrolyzing the 2 Tc24 isoforms. These data demonstrate that although the BC-SAg site in the mutants remained intact, their reduced susceptibility to IgM-mediated hydrolysis suggested that structural changes resulting from the Cys to Ser mutations altered accessibility to the catalytic site in the 2 isoforms.
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http://dx.doi.org/10.1645/17-7DOI Listing
October 2017

Likely Autochthonous Transmission of Trypanosoma cruzi to Humans, South Central Texas, USA.

Emerg Infect Dis 2017 03;23(3):500-503

Chagas disease, caused by Trypanosoma cruzi, is a major neglected tropical disease affecting the Americas. The epidemiology of this disease in the United States is incomplete. We report evidence of likely autochthonous vectorborne transmission of T. cruzi and health outcomes in T. cruzi-seropositive blood donors in south central Texas, USA.
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http://dx.doi.org/10.3201/eid2303.161157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5382766PMC
March 2017

Prevalence of Nasal Carriage in Human Immunodeficiency Virus-Infected and Uninfected Children in Botswana: Prevalence and Risk Factors.

Am J Trop Med Hyg 2017 Apr 6;96(4):795-801. Epub 2017 Feb 6.

Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania.

Abstract is an important cause of morbidity and mortality in children in sub-Saharan Africa (SSA). A major risk factor for staphylococcal infection is colonization of the anterior nares. We sought to define risk factors for carriage and characterize antimicrobial resistance patterns in children in Botswana. A cross-sectional study was conducted at two clinical sites in southern Botswana. Patients under 18 years of age underwent two nasal swabs and brief interviews, 4 weeks apart. Standard microbiological techniques were used. For persistent carriers, was isolated from swabs at both time points, and for intermittent carriers, was isolated from only one swab. Poisson regression with robust variance estimator was used to compare prevalence of carriage and the resistance phenotypes. Among 56 enrollees, prevalence of colonization was 55% ( = 31), of whom 42% ( = 13) were persistent carriers. Of human immunodeficiency virus-infected children, 64% ( = 9) were carriers. Risk factors for nasal carriage included a history of tuberculosis (prevalence ratio [PR] = 1.60; 95% confidence interval [CI] = 1.02, 2.51; = 0.040) and closer proximity to health care (PR = 0.89; 95% CI = 0.80, 0.99; = 0.048). Prior pneumonia was more common among persistent rather than intermittent carriers (PR = 2.64; 95% CI = 1.64, 4.23; < 0.001). Methicillin-resistant (MRSA) prevalence was 13%. Of isolates tested, 16% were resistant to three or more drugs ( = 7/44). In summary, children in southern Botswana are frequently colonized with . Antibiotic resistance, especially MRSA, is also widespread. Antibiotic recommendations for treatment of staphylococcal infections in SSA should take cognizance of these resistance patterns.
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http://dx.doi.org/10.4269/ajtmh.16-0650DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5392623PMC
April 2017

Staphylococcus aureus nasal colonization among HIV-infected adults in Botswana: prevalence and risk factors.

AIDS Care 2017 08 27;29(8):961-965. Epub 2017 Jan 27.

e The University of Texas Health Science Center School of Public Health , Houston , Texas.

We sought to determine the clinical and epidemiologic determinants of Staphylococcus aureus nasal colonization in HIV-infected individuals at two outpatient centers in southern Botswana. Standard microbiologic techniques were used to identify S. aureus and methicillin-resistant S. aureus (MRSA). In a sample of 404 HIV-infected adults, prevalence of S. aureus nasal carriage was 36.9% (n = 152) and was associated with domestic overcrowding and lower CD4 cell count. MRSA prevalence was low (n = 13, 3.2%), but more common among individuals with asthma and eczema. The implications of these findings for HIV management are discussed.
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http://dx.doi.org/10.1080/09540121.2017.1282600DOI Listing
August 2017

Hepatitis C virus infection and the risk of cancer among elderly US adults: A registry-based case-control study.

Cancer 2017 04 24;123(7):1202-1211. Epub 2017 Jan 24.

Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland.

Background: Hepatitis C virus (HCV) infection causes hepatocellular carcinoma (HCC) and subtypes of non-Hodgkin lymphoma (NHL). Associations with other cancers are not established. The authors systematically assessed associations between HCV infection and cancers in the US elderly population.

Methods: This was a registry-based case-control study using Surveillance, Epidemiology, and End Results (SEER)-Medicare data in US adults aged ≥66 years. Cases (n = 1,623,538) were patients who had first cancers identified in SEER registries (1993-2011). Controls (n = 200,000) were randomly selected, cancer-free individuals who were frequency-matched to cases on age, sex, race, and calendar year. Associations with HCV (documented by Medicare claims) were determined using logistic regression.

Results: HCV prevalence was higher in cases than in controls (0.7% vs 0.5%). HCV was positively associated with cancers of the liver (adjusted odds ratio [aOR] = 31.5; 95% confidence interval [CI], 29.0-34.3), intrahepatic bile duct (aOR, 3.40; 95% CI, 2.52-4.58), extrahepatic bile duct (aOR, 1.90; 95% CI, 1.41-2.57), pancreas (aOR, 1.23; 95% CI, 1.09-1.40), and anus (aOR, 1.97; 95% CI, 1.42-2.73); nonmelanoma nonepithelial skin cancer (aOR, 1.53; 95% CI, 1.15-2.04); myelodysplastic syndrome (aOR, 1.56; 95% CI, 1.33-1.83); and diffuse large B-cell lymphoma (aOR, 1.57; 95% CI, 1.34-1.84). Specific skin cancers associated with HCV were Merkel cell carcinoma (aOR, 1.92; 95% CI, 1.30-2.85) and appendageal skin cancers (aOR, 2.02; 95% CI, 1.29-3.16). Inverse associations were observed with uterine cancer (aOR, 0.64; 95% CI, 0.51-0.80) and prostate cancer (aOR, 0.73; 95% CI, 0.66-0.82). Associations were maintained in sensitivity analyses conducted among individuals without documented alcohol abuse, cirrhosis, or hepatitis B or human immunodeficiency virus infections and after adjustment for socioeconomic status. Associations of HCV with other cancers were not observed.

Conclusions: HCV is associated with increased risk of cancers other than HCC in the US elderly population, notably bile duct cancers and diffuse large B-cell lymphoma. These results support a possible etiologic role for HCV in an expanded group of cancers. Cancer 2017;123:1202-1211. © 2016 American Cancer Society.
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http://dx.doi.org/10.1002/cncr.30559DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6295146PMC
April 2017

The Clostridium difficile quorum-sensing molecule alters the Staphylococcus aureus toxin expression profile.

Int J Antimicrob Agents 2017 03 19;49(3):391-393. Epub 2017 Jan 19.

University of Texas School of Public Health, Center for Infectious Disease, Division of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas Health Science Center, Houston, TX, USA. Electronic address:

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http://dx.doi.org/10.1016/j.ijantimicag.2017.01.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5488688PMC
March 2017

Differential positive TSPOT assay responses to ESAT-6 and CFP-10 in health care workers.

Tuberculosis (Edinb) 2016 12 28;101S:S83-S91. Epub 2016 Sep 28.

Houston Methodist Hospital Institute, 6670 Bertner Ave, Houston, TX, 77030, USA. Electronic address:

Background: The TSPOT.TB (TSPOT) diagnostic test for latent tuberculosis infection is based on a cell-mediated response to the Mycobacteria tuberculosis antigens, ESAT-6 and/or CFP-10, producing an "interferon-gamma footprint". We investigated the within-sample and within-subject variability of positive TSPOT assays due to the individual assay antigens' reactivity.

Methods: Positive TSPOT assay frequencies due to ESAT-6 or CFP-10 among health care workers (HCWs) at 6-month intervals for 18 months were compared. Differences in result interpretation (positive or negative) for ESAT-6 and CFP10 and potential prognostic factors were investigated.

Results: There were 576 positive results in 8805 TSPOT assays representing 2418 participants. A significant difference was detected in positive TSPOT results due to a positive response to either ESAT-6, CFP-10 or both antigens at baseline through 12 M (p < 0.001), but not for the 18 M follow-up. Gender, ethnicity, occupation, previous positive tuberculin skin test (TST) and study site were significantly associated with specific antigen positivity.

Conclusions: Among our HCW samples with positive TSPOT assays, CFP-10 induced a larger proportion of positive TSPOT results than ESAT-6. Potential causes for this finding include: BCG vaccinated subpopulations, certain jobs, history of positive TST, U.S. birth, and study site. A high proportion of single-positive specimens may reflect false-positives results.
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http://dx.doi.org/10.1016/j.tube.2016.09.012DOI Listing
December 2016

Comparing TSPOT assay results between an Elispot reader and manual counts.

Tuberculosis (Edinb) 2016 12 28;101S:S92-S98. Epub 2016 Sep 28.

Houston Methodist Hospital Institute, 6670 Bertner Ave, Houston, TX, 77030, USA. Electronic address:

Background: The interferon gamma release assay, TSPOT.TB (TSPOT) can be read by several methodologies, including an Elispot reader or manually by technician. We compared the results from these two counting methods.

Methods: Automated and manual TSPOT results among 2481 United States health care workers were compared. Cohen's kappa coefficient was used to determine the inter-rater agreement. Univariate and multiple logistic regression were used to investigate selected variable contributions.

Results: No prognostic factors were associated with agreement of TSPOT results between counting methods. Agreement between TSPOT results were 92.3%, 89.5%, 93.0%, and 93.1% at baseline, and at follow-up at 6, 12, and 18 months, respectively. The inter-rater agreement for all test results was good (kappa = 0.71). There was a significant difference between individual technicians kappa coefficients (p < 0.001), but no significant increase in agreement over time for technicians (p = 0.394).

Conclusion: Commercial Elispot readers and manual counts have good agreement of TSPOT results in a low TB burden setting. Levels of agreement differed between individual technicians and automated reader from moderate to very good, indicating borderline results may be misinterpreted due to inter-rater variability. With no latent tuberculosis infection (LTBI) gold standard, it cannot be determined if one TSPOT reading method is better than another.
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http://dx.doi.org/10.1016/j.tube.2016.09.013DOI Listing
December 2016

Beyond type 2 diabetes, obesity and hypertension: an axis including sleep apnea, left ventricular hypertrophy, endothelial dysfunction, and aortic stiffness among Mexican Americans in Starr County, Texas.

Cardiovasc Diabetol 2016 Jun 8;15:86. Epub 2016 Jun 8.

Cardiology, Baylor College of Medicine, Houston, TX, 77030, USA.

Background: There is an increasing appreciation for a series of less traditional risk factors that should not be ignored when considering type 2 diabetes, obesity, hypertension, and cardiovascular disease. These include aortic stiffness, cardiac structure, impaired endothelial function and obstructive sleep apnea. They are associated to varying degrees with each disease categorization and with each other. It is not clear whether they represent additional complications, concomitants or antecedents of disease. Starr County, Texas, with its predominantly Mexican American population has been shown previously to bear a disproportionate burden of the major disease categories, but little is known about the distribution of these less traditional factors.

Methods: Type 2 diabetes, obesity and hypertension frequencies were determined through a systematic survey of Starr County conducted from 2002 to 2006. Individuals from this examination and an enriched set with type 2 diabetes were re-examined from 2010 to 2014 including assessment of cardiac structure, sleep apnea, endothelial function and aortic stiffness. Individual and combined frequencies of these inter-related (i.e., axis) conditions were estimated and associations evaluated.

Results: Household screening of 5230 individuals aged 20 years and above followed by direct physical assessment of 1610 identified 23.7 % of men and 26.7 % of women with type 2 diabetes, 46.2 and 49.5 % of men and women, respectively with obesity and 32.1 and 32.4 % with hypertension. Evaluation of pulse wave velocity, left ventricular mass, endothelial function and sleep apnea identified 22.3, 12.7, 48.6 and 45.2 % of men as having "at risk" values for each condition, respectively. Corresponding numbers in women were 16.0, 17.9, 23.6 and 28.8 %. Cumulatively, 88 % of the population has one or more of these while 50 % have three or more.

Conclusions: The full axis of conditions is high among Mexican Americans in Starr County, Texas. Individual and joint patterns suggest a genesis well before overt disease. Whether they are all mediated by common underlying factors or whether there exist multiple mechanisms remains to be seen.
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http://dx.doi.org/10.1186/s12933-016-0405-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4897940PMC
June 2016

Do Staphylococcus epidermidis Genetic Clusters Predict Isolation Sources?

J Clin Microbiol 2016 07 13;54(7):1711-1719. Epub 2016 Apr 13.

Department of Microbiology and Immunology, University of Mississippi Medical Center, Jackson, Mississippi, USA

Staphylococcus epidermidis is a ubiquitous colonizer of human skin and a common cause of medical device-associated infections. The extent to which the population genetic structure of S. epidermidis distinguishes commensal from pathogenic isolates is unclear. Previously, Bayesian clustering of 437 multilocus sequence types (STs) in the international database revealed a population structure of six genetic clusters (GCs) that may reflect the species' ecology. Here, we first verified the presence of six GCs, including two (GC3 and GC5) with significant admixture, in an updated database of 578 STs. Next, a single nucleotide polymorphism (SNP) assay was developed that accurately assigned 545 (94%) of 578 STs to GCs. Finally, the hypothesis that GCs could distinguish isolation sources was tested by SNP typing and GC assignment of 154 isolates from hospital patients with bacteremia and those with blood culture contaminants and from nonhospital carriage. GC5 was isolated almost exclusively from hospital sources. GC1 and GC6 were isolated from all sources but were overrepresented in isolates from nonhospital and infection sources, respectively. GC2, GC3, and GC4 were relatively rare in this collection. No association was detected between fdh-positive isolates (GC2 and GC4) and nonhospital sources. Using a machine learning algorithm, GCs predicted hospital and nonhospital sources with 80% accuracy and predicted infection and contaminant sources with 45% accuracy, which was comparable to the results seen with a combination of five genetic markers (icaA, IS256, sesD [bhp], mecA, and arginine catabolic mobile element [ACME]). Thus, analysis of population structure with subgenomic data shows the distinction of hospital and nonhospital sources and the near-inseparability of sources within a hospital.
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http://dx.doi.org/10.1128/JCM.03345-15DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4922092PMC
July 2016

Identification and Characterization of the Trypanosoma cruzi B-cell Superantigen Tc24.

Am J Trop Med Hyg 2016 Jan 23;94(1):114-121. Epub 2015 Nov 23.

Trypanosoma cruzi causes life-long disease after infection and leads to cardiac disease in 30% of infected individuals. After infection, the parasites are readily detectable in the blood during the first few days before disseminating to infect numerous cell types. Preliminary data suggested that the Tc24 protein that localizes to the T. cruzi membrane during all life stages possesses B-cell superantigenic properties. These antigens facilitate immune escape by interfering with antibody-mediated responses, particularly the avoidance of catalytic antibodies. These antibodies are an innate host defense mechanism present in the naive repertoire, and catalytic antibody-antigen binding results in hydrolysis of the target. We tested the B-cell superantigenic properties of Tc24 by comparing the degree of Tc24 hydrolysis by IgM purified from either Tc24 unexposed or exposed mice and humans. Respective samples were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis, silver stained, and the degree of hydrolysis was measured. Data presented in this report suggest that the T. cruzi Tc24 is a B-cell superantigen based on the observations that 1) Tc24 was hydrolyzed by IgM present in serum of unexposed mice and humans and 2) exposure to Tc24 eliminated catalytic activity as early as 4 days after T. cruzi infection.
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http://dx.doi.org/10.4269/ajtmh.15-0438DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4710414PMC
January 2016

Genome-Wide Association Study of Staphylococcus aureus Carriage in a Community-Based Sample of Mexican-Americans in Starr County, Texas.

PLoS One 2015 16;10(11):e0142130. Epub 2015 Nov 16.

Human Genetics Center, Division of Epidemiology, Human Genetics, and Environmental Sciences, University of Texas Health Science Center at Houston, Houston, TX, United States of America.

Staphylococcus aureus is the number one cause of hospital-acquired infections. Understanding host pathogen interactions is paramount to the development of more effective treatment and prevention strategies. Therefore, whole exome sequence and chip-based genotype data were used to conduct rare variant and genome-wide association analyses in a Mexican-American cohort from Starr County, Texas to identify genes and variants associated with S. aureus nasal carriage. Unlike most studies of S. aureus that are based on hospitalized populations, this study used a representative community sample. Two nasal swabs were collected from participants (n = 858) 11-17 days apart between October 2009 and December 2013, screened for the presence of S. aureus, and then classified as either persistent, intermittent, or non-carriers. The chip-based and exome sequence-based single variant association analyses identified 1 genome-wide significant region (KAT2B) for intermittent and 11 regions suggestively associated with persistent or intermittent S. aureus carriage. We also report top findings from gene-based burden analyses of rare functional variation. Notably, we observed marked differences between signals associated with persistent and intermittent carriage. In single variant analyses of persistent carriage, 7 of 9 genes in suggestively associated regions and all 5 top gene-based findings are associated with cell growth or tight junction integrity or are structural constituents of the cytoskeleton, suggesting that variation in genes associated with persistent carriage impact cellular integrity and morphology.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0142130PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4646511PMC
June 2016

Method for generation of peptide-specific IgY antibodies directed to Staphylococcus aureus extracellular fibrinogen binding protein epitope.

Biopolymers 2015 Sep;104(5):552-9

Division of Medicinal Chemistry and Microbiology, Wroclaw University of Technology, Faculty of Chemistry, Wybrzeze Wyspianskiego 27, 50-370, Wroclaw, Poland.

The IgY antibodies offer an attractive alternative to mammalian IgGs in research, diagnosis and medicine. The isolation of immunoglobulin Y from the egg yolks is efficient and economical, causing minimal suffering to animals. Here we present the methodology for the production of IgY antibodies specific to Staphylococcus aureus fibrinogen binding protein (Efb) and its peptidyl epitope (spanning residues 127-140). The Efb is an extracellular, adhesion protein which binds both human fibrinogen and complement C3 protein thus contributing to the high infectious potential of this pathogen. The selected epitope of Efb protein is responsible for the interaction with C3. The immunochemical characterization of both anti-Efb and epitope-specific IgY antibodies revealed their similar avidity, titer, and reactivity profile, although some differences in the hen's immune response to administered antigens is discussed.
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http://dx.doi.org/10.1002/bip.22695DOI Listing
September 2015

Adjuvant-dependent immunogenicity of Staphylococcus aureus Efb and Map proteins in chickens.

Vet Immunol Immunopathol 2015 Jul 16;166(1-2):50-6. Epub 2015 May 16.

Wroclaw University of Technology, Faculty of Chemistry, Division of Medicinal Chemistry and Microbiology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland. Electronic address:

The avian IgY antibodies generated in hens and isolated from egg yolk have gained in popularity as they present an alternative source of antibodies for diagnostic as well as therapeutic applications. One of the advantages of IgY technology are the large amounts of produced antibodies from a single animal combined with their high reactivity representing an attractive alternative for mammalian antibodies. Despite many known protocols for the immunization of chickens, the administration of new antigens often requires additional modification such as antigen dose or use of an adjuvant in order to elicit a significant immune response. We investigated the immunogenicity of three Staphylococcus aureus antigens including two extracellular proteins Map and Efb and one selected Efb105-124 epitope conjugated to KLH that were administered to the animals. Additionally, the immunization protocol included two adjuvant systems: Freund's complete adjuvant and Emulsigen-D. The results demonstrated a high immunostimulatory potency of Freund's complete adjuvant, especially in case of Efb compared to the immune response elicited by Emulsigen-D. However, after immunization with the KLH-Efb105-124 conjugate, the obtained antibodies showed similar reactivity regardless of adjuvant system used with the only exception being their avidity.
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http://dx.doi.org/10.1016/j.vetimm.2015.04.009DOI Listing
July 2015

Assessing the Biological Safety Profession's Evaluation and Control of Risks Associated with the Field Collection of Potentially Infectious Specimens.

Appl Biosaf 2015 Mar 1;20(1):27-40. Epub 2015 Apr 1.

The University of Texas Health Science Center at Houston, Houston, TX.

Because the origins of the biological safety profession are rooted in the control and prevention of laboratory-associated infections, the vocation focuses primarily on the safe handling of specimens within the laboratory. But in many cases, the specimens and samples handled in the lab are originally collected in the field where a broader set of possible exposure considerations may be present, each with varying degrees of controllability. The failure to adequately control the risks associated with collecting biological specimens in the field may result in illness or injury, and could have a direct impact on laboratory safety, if infectious specimens were packaged or transported inappropriately, for example. This study developed a web-based survey distributed to practicing biological safety professionals to determine the prevalence of and extent to which biological safety programs consider and evaluate field collection activities. In cases where such issues were considered, the data collected characterize the types of controls and methods of oversight at the institutional level that are employed. Sixty-one percent (61%) of the survey respondents indicated that research involving the field collection of biological specimens is conducted at their institutions. A majority (79%) of these field collection activities occur at academic institutions. Twenty-seven percent (27%) of respondents indicated that their safety committees do not consider issues related to biological specimens collected in the field, and only 25% with an oversight committee charged to review field collection protocols have generated a field research-specific risk assessment form to facilitate the assembly of pertinent information for a project risk assessment review. The results also indicated that most biosafety professionals (73% overall; 71% from institutions conducting field collection activities) have not been formally trained on the topic, but many (64% overall; 87% from institutions conducting field collection activities) indicated that training on field research safety issues would be helpful, and even more (71% overall; 93% from institutions conducting field collection activities) would consider participation in such a training course. Results obtained from this study can be used to develop a field research safety toolkit and associated training curricula specifically targeted to biological safety professionals.
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http://dx.doi.org/10.1177/153567601502000104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5760186PMC
March 2015