Publications by authors named "Pilar Gomez"

30 Publications

  • Page 1 of 1

Lemmel syndrome: uncommon complication of periampullary duodenal diverticulum.

Rev Esp Enferm Dig 2021 Sep 7. Epub 2021 Sep 7.

Radiodiagnóstico, Hospital Universitario Basurto.

Lemmel's syndrome is an uncommon entity that causes obstructive jaundice due to a periampullary duodenal diverticulum, in the absence of choledolithiasis or neoplasia. To date, there are few published cases and the etiopathogenesis is unclear.
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http://dx.doi.org/10.17235/reed.2021.8258/2021DOI Listing
September 2021

Renoprotective role of bariatric surgery in patients with established chronic kidney disease.

Clin Kidney J 2021 Sep 23;14(9):2037-2046. Epub 2020 Dec 23.

Department of Nephrology, Hospital Universitario 12 de Octubre, Madrid, Spain.

Background: Bariatric surgery (BS) has been postulated as the most effective measure for weight reduction. Weight loss improves metabolic parameters and exerts changes in renal function that lead to the amelioration of absolute or relative glomerular hyperfiltration, a condition that may be renoprotective in the long term. However, few studies have demonstrated the influence of BS in patients with severe obesity and chronic kidney disease (CKD). Our objective was to analyse the evolution of renal function, adipose tissue-derived molecules and inflammatory parameters in patients with CKD after BS.

Methods: This is an observational and prospective study. Thirty patients were screened and 12 were included between January 2016 and January 2018 with a 24-month follow-up. Glomerular filtration rate (GFR) was determined by plasma iohexol clearance. Adipokines, cytokines, circulating hormones and fibrotic parameters were evaluated before and 12 months after BS using the Bioplex system.

Results: The mean age was 50.6 years and 58.3% were males. Seven patients had a body mass index >40 kg/m and 66.7% were diabetic. Twenty-four months following BS there was a significant decrease in body weight (36.4%). Proteinuria decreased by 63.7 ± 28.2%. Measured GFR significantly diminished from before surgery to Month 24 after surgery (94 ± 44 to 79 ± 44 mL/min, P = 0.03). There was a significant decrease in adipocyte-derived molecules (leptin and vifastin) as well as in pro-inflammatory cytokines [interleukin (IL)-1β, tumour necrosis factor α, IL-6 and monocyte chemoattractant protein-1] and other circulating factors (vascular endothelial growth factor and transforming growth factor β isoforms).

Conclusions: BS is an effective option to prevent kidney damage in obese subjects with CKD due to the improvement of glomerular hyperfiltration, adipocyte cytokines metabolic and inflammatory parameters.
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http://dx.doi.org/10.1093/ckj/sfaa266DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8406062PMC
September 2021

Occupational contact dermatitis: Return to work using a multidisciplinary clinic model.

Contact Dermatitis 2021 Jul 22. Epub 2021 Jul 22.

Department of Medicine, University of Toronto, Toronto, Ontario, Canada.

Background: Occupational contact dermatitis often results in work disruption. Return-to-work (RTW) is an important outcome.

Objective: The objective of this study was to determine RTW outcomes and factors associated with such outcomes using a multidisciplinary clinic model.

Methods: Chart abstraction was performed for 194 workers who received RTW assistance over a 6-year period. Elements abstracted included demographic and diagnostic information and information about the RTW program including principles, program components, barriers, and facilitators.

Results: Of the 902 workers seen for dermatologic assessment, 194 received RTW assistance. At initial assessment, 37% were not working because of their skin disease, and at follow-up, 7% were not working because of their skin disease. The RTW plan components included a graduated or trial of RTW, specific recommendations for avoiding exposure, personal protective equipment, skin management, and ongoing skin monitoring. Principles associated with successful RTW included good communication and the availability of modified work and a worker adherence to the plan. Barriers included lack of modified work, unresponsive employers, and ongoing skin problems.

Conclusions: Specific approaches are important to identify if RTW is to be successful for workers with occupational contact dermatitis.
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http://dx.doi.org/10.1111/cod.13945DOI Listing
July 2021

SEGHI Study: Defining the Best Surveillance Strategy in Hodgkin Lymphoma after First-Line Treatment.

Cancers (Basel) 2021 May 17;13(10). Epub 2021 May 17.

Hematology Department, Hospital Clínico de Salamanca, 37008 Salamanca, Spain.

The optimal strategy for early surveillance after first complete response is unclear in Hodgkin lymphoma. Thus, we compared the various follow-up strategies in a multicenter study. All the included patients had a negative positron emission tomography/computed tomography at the end of induction therapy. From January 2007 to January 2018, we recruited 640 patients from 15 centers in Spain. Comparing the groups in which serial imaging were performed, the clinical/analytical follow-up group was exposed to significantly fewer imaging tests and less radiation. With a median follow-up of 127 months, progression-free survival at 60 months of the entire series was 88% and the overall survival was 97%. No significant differences in survival or progression-free survival were found among the various surveillance strategies. This study suggests that follow-up approaches with imaging in Hodgkin lymphoma provide no benefits for patient survival, and we believe that clinical/analytical surveillance for this group of patients could be the best course of action.
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http://dx.doi.org/10.3390/cancers13102412DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8156414PMC
May 2021

RELINF: prospective epidemiological registry of lymphoid neoplasms in Spain. A project from the GELTAMO group.

Ann Hematol 2020 Apr 20;99(4):799-808. Epub 2020 Feb 20.

Haematology Department, Hospital Dr. Peset, Valencia, Spain.

Lymphomas are a large, heterogeneous group of neoplasms with well-defined characteristics, and this heterogeneity highlights the importance of epidemiological data. Knowledge of local epidemiology is essential to optimise resources, design clinical trials, and identify minority entities. Given there are few published epidemiological data on lymphoma in Spain, the Spanish Lymphoma and Autologous Bone Marrow Transplant Group created the RELINF project. The aim of this project is to determine the frequencies and distribution of lymphoid neoplasms in Spain and to analyse survival. We developed an online platform for the prospective collection of data on newly diagnosed cases of lymphoma in Spain between January 2014 and July 2018; 11,400 patients were registered. Diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL) were the most frequent lymphomas in our series. Marginal B cell lymphoma frequency was higher than that reported in other studies, representing more than 11% of mature B cell lymphomas. Peripheral T cell lymphoma not otherwise specified (PTCL-NOS) was the most common subtype of T cell lymphoma, and NK/T cell lymphomas were more frequent than expected (5.4% of total). Hodgkin's lymphoma accounted for 12% of lymphoproliferative syndromes. Overall survival was greater than 90% at 2 years for indolent B cell lymphomas, and approximately 60% for DLBCL, somewhat lower than that previously reported. Survival was poor for PTCL-NOS and angioimmunoblastic T cell lymphoma, as expected; however, it was somewhat better than that in other studies for anaplastic large cell anaplastic lymphoma kinase lymphomas. This is the first prospective registry to report the frequencies, distribution, and survival of lymphomas in Spain. The frequencies and survival data we report here are globally consistent with that reported in other Western countries. These updated frequencies and survival statistics are necessary for developing appropriate management strategies for neoplasias in the Spanish population.
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http://dx.doi.org/10.1007/s00277-020-03918-6DOI Listing
April 2020

Introducing a "Workplace Prescription" to Facilitate Return to Work for Workers With Occupational Contact Dermatitis.

J Cutan Med Surg 2017 Nov/Dec;21(6):573-575

1 Department of Occupational and Environmental Health, St Michael's Hospital, Toronto, ON, Canada.

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http://dx.doi.org/10.1177/1203475417716328DOI Listing
July 2019

Variation and Distribution of L-A Helper Totiviruses in Saccharomyces sensu stricto Yeasts Producing Different Killer Toxins.

Toxins (Basel) 2017 10 11;9(10). Epub 2017 Oct 11.

Instituto de Biología Funcional y Genómica, IBFG-CSIC, Universidad de Salamanca, 37007 Salamanca, Spain.

Yeasts within the cluster can produce different killer toxins. Each toxin is encoded by a medium size (1.5-2.4 Kb) M dsRNA virus, maintained by a larger helper virus generally called L-A (4.6 Kb). Different types of L-A are found associated to specific Ms: L-A in K1 strains and L-A-2 in K2 strains. Here, we extend the analysis of L-A helper viruses to yeasts other than , namely , and . Our sequencing data from nine new L-A variants confirm the specific association of each toxin-producing M and its helper virus, suggesting co-evolution. Their nucleotide sequences vary from 10% to 30% and the variation seems to depend on the geographical location of the hosts, suggesting cross-species transmission between species in the same habitat. Finally, we transferred by genetic methods different killer viruses from into or viruses from into or . In the foster hosts, we observed no impairment for their stable transmission and maintenance, indicating that the requirements for virus amplification in these species are essentially the same. We also characterized new killer toxins from and constructed "superkiller" strains expressing them.
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http://dx.doi.org/10.3390/toxins9100313DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5666360PMC
October 2017

Return to Work for Nurses With Hand Dermatitis.

Dermatitis 2016 Sep-Oct;27(5):308-12

From the *Faculty of Medicine and Dentistry, University of Alberta, Edmonton; †Department of Occupational and Environmental Health, St Michael's Hospital; ‡Department of Occupational Science and Occupational Therapy, §Dalla Lana School of Public Health, and ∥Department of Medicine, University of Toronto; and ¶Centre for Research in Inner City Health, Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Ontario, Canada.

Background: Occupational skin disease is common in healthcare workers. If the healthcare worker develops moderate to severe dermatitis, return to work (RTW) may be challenging.

Objectives: The study objectives were to review the impact of an RTW program on the work status of nurses with occupational hand dermatitis and to identify successful intervention methods and strategies.

Methods: Nurses who received RTW services at a tertiary occupational medicine clinic were identified, and information related to their diagnosis and RTW was abstracted from their charts.

Results: Eighteen nurses with irritant hand dermatitis who received RTW services were identified. Twelve nurses (67%) were performing administrative duties because of their skin condition when admitted to the RTW program, and others were performing patient care with modifications. A graduated RTW trial was commonly implemented with optimized skin care management and monitoring by physicians and the RTW coordinator. Upon discharge, 14 nurses (78%) had returned to their nursing roles with direct patient care, 3 (17%) were working as nurses in non-patient care roles, and 1 (6%) was on permanent disability.

Conclusions: A graduated RTW trial to reduce cumulative irritant exposure is a crucial strategy to facilitate nurses' transition back to work and to maintain direct patient care nursing roles.
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http://dx.doi.org/10.1097/DER.0000000000000215DOI Listing
February 2018

Massive subcutaneous emphysema after traumatic pneumothorax.

Pan Afr Med J 2016 29;23:56. Epub 2016 Feb 29.

Department of Internal Medicine, Hospital Universitario Nuestra Señora de Candelaria, Ctra, Del Rosario 145, 38010 Sta, Cruz de Tenerife, Spain.

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http://dx.doi.org/10.11604/pamj.2016.23.56.8947DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4862797PMC
February 2017

L-A-lus, a new variant of the L-A totivirus found in wine yeasts with Klus killer toxin-encoding Mlus double-stranded RNA: possible role of killer toxin-encoding satellite RNAs in the evolution of their helper viruses.

Appl Environ Microbiol 2013 Aug 31;79(15):4661-74. Epub 2013 May 31.

Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas/Universidad de Salamanca, Salamanca, Spain.

Yeast killer viruses are widely distributed in nature. Several toxins encoded in double-stranded RNA (dsRNA) satellites of the L-A totivirus have been described, including K1, K2, K28, and Klus. The 4.6-kb L-A genome encodes the Gag major structural protein that forms a 39-nm icosahedral virion and Gag-Pol, a minor fusion protein. Gag-Pol has transcriptase and replicase activities responsible for maintenance of L-A (or its satellite RNAs). Recently we reported a new killer toxin, Klus. The L-A virus in Klus strains showed poor hybridization to known L-A probes, suggesting substantial differences in their sequences. Here we report the characterization of this new L-A variant named L-A-lus. At the nucleotide level, L-A and L-A-lus showed only 73% identity, a value that increases to 86% in the amino acid composition of Gag or Gag-Pol. Two regions in their genomes, however, the frameshifting region between Gag and Pol and the encapsidation signal, are 100% identical, implying the importance of these two cis signals in the virus life cycle. L-A-lus shows higher resistance than L-A to growth at high temperature or to in vivo expression of endo- or exonucleases. L-A-lus also has wider helper activity, being able to maintain not only Mlus but also M1 or a satellite RNA of L-A called X. In a screening of 31 wine strains, we found that none of them had L-A; they carried either L-A-lus or a different L-A variant in K2 strains. Our data show that distinct M killer viruses are specifically associated with L-As with different nucleotide compositions, suggesting coevolution.
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http://dx.doi.org/10.1128/AEM.00500-13DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3719527PMC
August 2013

Effects of branched-chain amino acids supplementation in patients with cirrhosis and a previous episode of hepatic encephalopathy: a randomized study.

Am J Gastroenterol 2011 Jun 15;106(6):1081-8. Epub 2011 Feb 15.

Servei de Medicina Interna-Hepatologia, Hospital Vall d'Hebron, Barcelona, Spain.

Objectives: Protein intake impacts on nutritional status and may determine the recurrence of hepatic encephalopathy (HE). A low-protein diet has been considered the standard treatment after an episode of HE, while branched-chain amino acids (BCAA) have been shown to improve minimal HE. We performed a study to investigate the long-term effects of supplementing a protein-controlled diet with BCAA.

Methods: A randomized, double-blind, multicenter study that included 116 patients with cirrhosis and a previous episode of HE was conducted in four tertiary care hospitals. All patients received a standard diet of 35 kcal/kg per day and 0.7 g of proteins/kg per day and a supplement of 30 g of BCAA (BCAA group) or maltodextrin (MDX group) during 56 weeks.

Results: The actuarial risk of remaining free of HE did not differ between groups (BCAA=47%, MDX=34%, P=0.274), but patients in the BCAA group exhibited a better outcome on two neuropsychological tests and an increase in the mid-arm muscle circumference. Recurrence was associated with low plasma albumin at baseline and a decrease in sodium and an increase in creatinine during follow-up. Patients with recurrence of HE exhibited a lack of improvement in global cognitive function.

Conclusions: Diet supplementation with BCAA after an episode of HE does not decrease recurrence of HE. However, supplementation with BCAA improves minimal HE and muscle mass. Identification of risk factors for recurrence of HE may allow the development of new preventive therapies that could decrease the neuropsychological sequelae of repeated episodes of HE.
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http://dx.doi.org/10.1038/ajg.2011.9DOI Listing
June 2011

[Association of hyperhomocysteinemia with liver steatosis in patients with chronic hepatitis C].

Med Clin (Barc) 2011 Jan 3;136(2):45-9. Epub 2010 Nov 3.

Unidad de Lípidos y Aterosclerosis, Servicio de Medicina Interna, Hospital Universitario 12 de Octubre, Madrid, España.

Background And Objectives: Liver steatosis in chronic hepatitis C (CHC) is related to viral and metabolic factors and likely to genetic factors. The aim of this study was to know if hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR)-C677T polymorphisms are associated with liver steatosis in nonalcoholic patients with CHC.

Patients And Method: In 54 consecutive patients with CHC, alcohol consumption less than 40g/week, and no other causes of liver disease, a liver biopsy was performed. All variables were obtained at the time of biopsy. MTHFR-C677T was also performed in 128 healthy subjects, with age and gender similar to the patients.

Results: Liver steatosis was found in 33 patients (61%), 30 of them having a mild degree. Hyperhomocysteinemia was more prevalent in patients with steatosis (61% vs 24%; p=0.008) and overweight tended to be more prevalent in the same patients (61% vs 33%; p=0.05). All patients with virus C genotype 3 had steatosis. Viral load, liver inflammatory and fibrosis score were not different in patients with and without steatosis. MTHFR-C677T polymorphism was similar in controls and cases and in cases with and without steatosis. A multiple logistic regression showed that hyperhomocysteinemia was associated with liver steatosis after adjustment for age and sex (OR: 3.94; 95% CI: 1.09-14.29), and adjustment for overweight (OR: 4.43; 95% CI: 1.27-15.51).

Conclusions: In nonalcoholic patients with CHC mild liver steatosis is frequent, and is associated with hyperhomocysteinemia. An association between steatosis and MTHFR-C677T polymorphism was not found.
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http://dx.doi.org/10.1016/j.medcli.2010.05.024DOI Listing
January 2011

Melanopsin-mediated light-sensing in amphioxus: a glimpse of the microvillar photoreceptor lineage within the deuterostomia.

Commun Integr Biol 2009 Sep;2(5):441-3

Instituto de Genética, Woods Hole, MA, USA.

The two fundamental lineages of photoreceptor cells, microvillar and ciliary, were long thought to be a prerogative of invertebrate and vertebrate organisms, respectively. However evidence of their ancient origin, preceding the divergence of these two branches of metazoa, suggests instead that they should be ubiquitously distributed. Melanopsin-expressing 'circadian' light receptors may represent the remnants of the microvillar photo- receptors amongst vertebrates, but they lack the characteristic architecture of this lineage, and much remains to be clarified about their signaling mechanisms. Hesse and Joseph cells of the neuronal tube of amphioxus (Branchiostoma fl.)-the most basal chordate extant-turn out to be depolarizing primary microvillar photoreceptors, that generate a melanopsin-initiated, PLC-dependent response to light, mobilizing internal Ca and increasing a membrane conductance selective to Na and Ca ions. As such, they represent a canonical instance of invertebrate-like visual cells in the chordate phylum.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775246PMC
http://dx.doi.org/10.4161/cib.2.5.9244DOI Listing
September 2009

Accurately estimating breast cancer survival in Spain: cross-matching local cancer registries with the National Death Index.

Rev Panam Salud Publica 2009 Jul;26(1):51-4

Departamento de Salud y Consumo, Gobierno de Aragón, Spain; Instituto Aragonés de Ciencias de la Salud, Zaragoza, Spain.

Objectives: To assess the impact of using data from the National Death Index (NDI) of Spain to estimate breast cancer survival rates among residents of Girona and Zaragoza diagnosed in 1995-1999.

Methods: This was an observational, longitudinal epidemiologic study, using two population-based cancer registries. Data collected were of female residents of Girona or Zaragoza who had been diagnosed with breast cancer in 1995-1999. Observed and relative 5-year survival rates were estimated, first using the information available from the Girona and Zaragoza cancer registries, and then with the inclusion of NDI data. The 5-year relative survival rate and corresponding 95% Confidence Intervals were estimated using the Hakulinen method. The Kaplan-Maier method and Log Rank test were used to compare survival curves.

Results: No statistically significant difference in survival curves was observed in Girona for the data obtained before and after cross-matching with the NDI. However, there was a significant difference in Zaragoza. A comparison of the relative survival rates of each of the two registries before NDI cross-matching showed differences of 3.9% (5-year) and 16.1% (10-year) between the two, whereas after the cross-match, the difference was only 0.5% (5-year) and 1.2% (10-year).

Conclusions: In Spain it is imperative that there be systematic use of NDI data to supplement cancer registries, so that comparisons of relative survival rates between registries can be improved.
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http://dx.doi.org/10.1590/s1020-49892009000700008DOI Listing
July 2009

Prolonged calcium influx after termination of light-induced calcium release in invertebrate photoreceptors.

J Gen Physiol 2009 Sep;134(3):177-89

Facultad de Ciencias, Instituto de Genética, Universidad Nacional de Colombia, Bogotá, Colombia.

In microvillar photoreceptors, light stimulates the phospholipase C cascade and triggers an elevation of cytosolic Ca2+ that is essential for the regulation of both visual excitation and sensory adaptation. In some organisms, influx through light-activated ion channels contributes to the Ca2+ increase. In contrast, in other species, such as Lima, Ca2+ is initially only released from an intracellular pool, as the light-sensitive conductance is negligibly permeable to calcium ions. As a consequence, coping with sustained stimulation poses a challenge, requiring an alternative pathway for further calcium mobilization. We observed that after bright or prolonged illumination, the receptor potential of Lima photoreceptors is followed by the gradual development of an after-depolarization that decays in 1-4 minutes. Under voltage clamp, a graded, slow inward current (Islow) can be reproducibly elicited by flashes that saturate the photocurrent, and can reach a peak amplitude in excess of 200 pA. Islow obtains after replacing extracellular Na+ with Li+, guanidinium, or N-methyl-D-glucamine, indicating that it does not reflect the activation of an electrogenic Na/Ca exchange mechanism. An increase in membrane conductance accompanies the slow current. Islow is impervious to anion replacements and can be measured with extracellular Ca2+ as the sole permeant species; Ba can substitute for Ca2+ but Mg2+ cannot. A persistent Ca2+ elevation parallels Islow, when no further internal release takes place. Thus, this slow current could contribute to sustained Ca2+ mobilization and the concomitant regulation of the phototransduction machinery. Although reminiscent of the classical store depletion-operated calcium influx described in other cells, Islow appears to diverge in some significant aspects, such as its large size and insensitivity to SKF96365 and lanthanum; therefore, it may reflect an alternative mechanism for prolonged increase of cytosolic calcium in photoreceptors.
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http://dx.doi.org/10.1085/jgp.200910214DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2737223PMC
September 2009

[Investigation of a foodborne intoxication in a high-density penitentiary center].

Gac Sanit 2007 Nov-Dec;21(6):452-7

Programa de Epidemiología Aplicada de Campo, Centro Nacional de Epidemiología, Instituto de Salud Carlos III, Madrid, España.

Background: On September 25 2005, more than 100 inmates (almost 5% of the 1,800 prison population) experienced sudden onset gastroenteritis. This outbreak was the largest foodborne outbreak described in a prison population in Spain. Our objective was to confirm the outbreak, identify risk factors, implement control measures, and provide recommendations.

Methods: We conducted a cohort analysis of a stratified random sample of all the inmates, a cohort analysis of the one of the prison blocks, and an environmental investigation.

Results: A total of 221 inmates were selected, of which 196 were interviewed. Twenty-eight percent had gastroenteritis and the main symptoms were abdominal pain (85%) and diarrhea (71%). All foods consumed caused similar attack rates. Factors associated with the risk of illness were eating the entire portion of seafood cocktail at lunch or all of the fried shrimp at dinner on September 24 (RR = 2; 95% CI, 1.1-3.8, and RR = 1.8; 95% CI, 1.1-3.1). Analysis of one of the prison blocks yielded results similar to those of the random sample. Clostridium perfringens, Bacillus cereus and Escherichia coli were isolated from a sample of the seafood cocktail.

Conclusion: A gastroenteritis outbreak caused by several pa-thogens was confirmed. Both the reported symptoms and the calculated incubation periods corresponded to the pathogens isolated. Preparation of food in prison facilities should meet minimum safety standards, including refrigeration and training of food handlers.
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http://dx.doi.org/10.1157/13112237DOI Listing
February 2008

Effect of folic acid treatment on carotid intima-media thickness of patients with coronary disease.

Int J Cardiol 2007 Jun 17;118(3):345-9. Epub 2006 Oct 17.

Hospital Universitario 12 de Octubre, Madrid, Service of Internal Medicine (Lipid and Atherosclerosis Unit), Madrid, Spain.

Background: Carotid intima-media thickness (CIMT) is a surrogate marker of cardiovascular morbility. Hyperhomocysteinemia, which is an independent cardiovascular risk factor, is associated with low folate levels. The aim of this study was to evaluate the effect of folic acid treatment on the evolution of CIMT in patients with coronary disease and homocysteinemia > or =9 micromol/l.

Methods: In 137 consecutive patients with coronary disease treated with statins and normal vitamin B12 values, a randomized treatment with open-label folic acid 2.5 mg/day (group A) or not (group B) was performed during 3 years. CIMT was evaluated by two-dimensional ultrasonography baseline and at the final of the study.

Results: Clinical, biochemical parameters and CIMT were similar in both groups of patients. Homocysteine levels decreased (12.4+/-3.4 vs. 10.3+/-2.4 micromol/l; p<0.001) in group A, but not in group B. CIMT did not change neither in group A (0.71+/-0.23 vs. 0.69+/-0.20 mm; p=0.34) nor in group B (0.74+/-0.23 vs. 0.72+/-0.29 mm; p=0.39). In 12 patients of group A with methylenetetrahydrofolate reductase (MTHFR) 677TT mutation a decrease of CIMT was found (0.83+/-0.35 vs. 0.72+/-0.27 mm; p=0.02), but a multiple linear regression only showed a trend to the association between CIMT changes and MTHFR 677TT (p=0.051), probably due to the small number of patients with this mutation.

Conclusions: Long-time treatment with folic acid in patients with coronary disease and normal values of vitamin B12 decreases homocysteine levels. A CIMT decrease is observed in treated patients with MTHFR 677TT mutation.
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http://dx.doi.org/10.1016/j.ijcard.2006.07.031DOI Listing
June 2007

[Effect of hyperhomocysteinemia and methylenetetrahydrofolate reductase 677C --> T mutation in venous thromboembolism risk of young adults].

Med Clin (Barc) 2005 Apr;124(14):532-4

Servicio de Medicina Interna, Hospital Universitario 12 de Octubre, Madrid, Spain.

Background And Objective: To investigate whether hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR) 677C --> T mutation are associated with venous thromboembolism in young Spanish adults.

Patients And Method: One hundred adult patients younger than 50 years and 177 controls with similar age and gender.

Results: Hyperhomocysteinemia was present in 21% of the patients and 3.3% of the controls (p < 0.001), and MTHFR 677C --> T mutation was found in 25 and 14.7%, respectively (p = 0.03). Odds ratio (OR) for thromboembolism in hyperhomocysteinemic patients was 7.5 (95% CI, 2.9-19.2; p < 0.001), and in patients with MTHFR 677C --> T mutation the OR was 1.9 (95% CI, 1.1-3.5; p = 0.03). In a subgroup of 76 patients without other thrombogenic factors, thromboembolism persisted associated with hyperhomocysteinemia, yet an association with MTHFR 677C --> T mutation was not confirmed.

Conclusions: Hyperhomocysteinemia, but not MTHFR 677C --> T mutation, is a risk factor for venous thromboembolism in young adults without other thrombogenic factors.
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http://dx.doi.org/10.1157/13073939DOI Listing
April 2005

[Hyperhomocysteinemia and treatment with antiepileptic drugs. Effects of different doses of folic acid].

Med Clin (Barc) 2005 Apr;124(14):521-4

Servicio de Medicina Interna, Hospital Universitario 12 de Octubre, Madrid, Spain.

Background And Objective: An increase homocysteine values, which is an independent risk factor for atherotrombotic disease, can be produced with antiepileptic treatment. The aims of this study were: 1) to assess the frequency and determinant factors of hyperhomocysteinemia in adult patients receiving antiepileptic drugs, and 2) to know the effect of different doses of folic acid.

Patients And Method: Ninety eight patients and 100 healthy controls similar in age and gender were studied. Eighty six patients were treated with hepatic enzyme inductors (diphenylhydantoine and/or phenobarbital and/or primidone and/or carbamazepine), 5 received non inductors (valproate) and 7 were treated with both in combination. Thirty eight patients were randomized to receive in an open and concurrent way folic acid, 0.2 mg (n = 18) or 5.2 mg (n = 20) daily for 3 months.

Results: Homocysteine values were increased in patients in relation with controls (mean [SD]12.2 [6.7] 95% confidence interval [CI],10.0-13.5 vs 8.8[2.2] 95% CI, 8.3-9.2 micromol/l; p < 0.001). Hyperhomocysteinemia was found in 28 patients and 4 controls (28.6% vs 4.0%; p < 0.001). In a multivariate analysis hyperhomocysteinemia was positively associated with treatment with antiepileptic inductors and negatively with folate values and female gender. Homocysteine values decreased after treatment with folic acid at high and low doses (p < 0.001 for both groups), and the values observed in the latter group were similar to those in healthy controls.

Conclusions: Hyperhomocysteinemia is frequent in patients treated with antiepileptic drugs. Treatment with hepatic enzyme inductors and low folate values are predictors of hyperhomocysteinemia. Administration of folic acid, even at very low doses, produces a significant decrease of homocysteinemia in these patients.
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http://dx.doi.org/10.1157/13073937DOI Listing
April 2005

A direct signaling role for phosphatidylinositol 4,5-bisphosphate (PIP2) in the visual excitation process of microvillar receptors.

J Biol Chem 2005 Apr 1;280(17):16784-9. Epub 2005 Mar 1.

Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, USA.

In microvillar photoreceptors the pivotal role of phospholipase C in light transduction is undisputed, but previous attempts to account for the photoresponse solely in terms of downstream products of phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis have proved wanting. In other systems PIP2 has been shown to possess signaling functions of its own, rather than simply serving as a precursor molecule. Because illumination of microvillar photoreceptors cells leads to PIP2 break-down, a potential role for this phospholipid in phototransduction would be to help maintain some element(s) of the transduction cascade in the inactive state. We tested the effect of intracellular dialysis of PIP2 on voltage-clamped molluscan photoreceptors and found a marked reduction in the amplitude of the photocurrent; by contrast, depolarization-activated calcium and potassium currents were unaffected, thus supporting the notion of a specific effect on light signaling. In the dark, PIP2 caused a gradual outward shift of the holding current; this change was due to a decrease in membrane conductance and may reflect the suppression of basal openings of the light-sensitive conductance. The consequences of depleting PIP2 were examined in patches of light-sensitive microvillar membrane screened for the exclusive presence of light-activated ion channels. After excision, superfusion with anti-PIP2 antibodies induced the appearance of single-channel currents. Replenishment of PIP2 by exogenous application reverted the effect. These data support the notion that PIP2, in addition to being the source of inositol trisphosphate and diacylglycerol, two messengers of visual excitation, may also participate in a direct fashion in the control of the light-sensitive conductance.
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http://dx.doi.org/10.1074/jbc.M414538200DOI Listing
April 2005

Calcium-independent, cGMP-mediated light adaptation in invertebrate ciliary photoreceptors.

J Neurosci 2005 Feb;25(8):2042-9

Department of Physiology and Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, USA.

Calcium is thought to be essential for adaptation of sensory receptor cells. However, the transduction cascade of hyperpolarizing, ciliary photoreceptors of the scallop does not use IP3-mediated Ca release, and the light-sensitive conductance is not measurably permeable to Ca2+. Therefore, two typical mechanisms that couple the light response to [Ca]i changes seem to be lacking in these photoreceptors. Using fluorescent indicators, we determined that, unlike in their microvillar counterparts, photostimulation of ciliary cells under voltage clamp indeed evokes no detectable change in cytosolic Ca. Notwithstanding, these cells exhibit all of the hallmarks of light adaptation, including response range compression, sensitivity shift, and photoresponse acceleration. A possible mediator of Ca-independent sensory adaptation is cGMP, the second messenger that regulates the light-sensitive conductance; cGMP and 8-bromo cGMP not only activate light-dependent K channels but also reduce the amplitude of the light response to an extent greatly in excess of that expected from simple occlusion between light and chemical stimulation. In addition, these substances accelerate the time course of the photocurrent. Tests with pharmacological antagonists suggest that protein kinase G may be a downstream effector that controls, in part, the cGMP-triggered changes in photoresponse properties during light adaptation. However, additional messengers are likely to be implicated, especially in the regulation of response kinetics. These observations suggest a novel feedback inhibition pathway for signaling sensory adaptation.
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http://dx.doi.org/10.1523/JNEUROSCI.5129-04.2005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6726048PMC
February 2005

[Homocysteine and progression of carotid atherosclerosis in patients with coronary disease].

Med Clin (Barc) 2003 Nov;121(15):561-4

Unidad de Lípidos y Aterosclerosis. Servicio de Medicina Interna. Hospital Universitario 12 de Octubre. Madrid. Spain.

Background And Objective: Carotid intima-media thickness (IMT) is a marker of generalized atherosclerosis. Sequential evaluation of carotid IMT has permitted to know the factors involved in its progression. However, there are few studies about the influence of homocysteine in such progression. The aim of this work was to know the effect of homocysteine values on the evolution of carotid IMT in patients with coronary disease.

Patients And Method: Carotid IMT (baseline and after 4 years of follow-up) was evaluated by a B-mode ultrasonography in 187 patients with coronary disease (166 males and 21 females; age: mean [standard deviation], 60 [7] years); 185 patients were treated with statins from the beginning of the study.

Results: Carotid IMT progression was confirmed in 59 patients (31.6%; 95% confidence interval [CI], 25.0-38.7%). Cardiovascular risk factors, basal biochemical parameters and methylenetetrahydrofolate reductase-C677T polymorphism were similar in patients with and without progression except for homocysteine values which were higher in the former (13.3 [5.3]; 95% CI, 12.0-14.6 vs 11.1 [3.5]; 95% CI, 10.5-11.7 (mol/l; p = 0.001). Biochemical changes at the end of the study were similar in both groups. In the multivariate analysis, IMT progression was associated with basal values of homocysteine (odds ratio [OR] 1.19; 95% CI, 1.07-1.31; p = 0.0008), female gender (OR 3.50; 95% CI, 1.17-10.50; p = 0.02), hypertension (OR 2.52; 95% CI, 1.14-5.59; p = 0.02) and basal high-density lipoprotein (HDL)-cholesterol values (OR, 0.94; 95% CI, 0.90-0.98; p = 0.009).

Conclusions: The concentration of homocysteine is associated with the progression of carotid atherosclerosis in patients with coronary heart disease treated with statins.
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http://dx.doi.org/10.1016/s0025-7753(03)74017-2DOI Listing
November 2003

Mitochondrial methionyl-tRNAfMet formyltransferase from Saccharomyces cerevisiae: gene disruption and tRNA substrate specificity.

Biochemistry 2003 Feb;42(4):932-9

Laboratoire de Biochimie, Unité Mixte de Recherche 7654, CNRS-Ecole Polytechnique, F-91128 Palaiseau Cedex, France.

Initiation of protein synthesis in bacteria, mitochondria, and chloroplasts involves a formylated methionyl-tRNA species. Formylation of this tRNA is catalyzed by a methionyl-tRNA(f)(Met) formyltransferase (formylase). Upon inactivation of the gene encoding formylase, the growth rate of Escherichia coli is severely decreased. This behavior underlines the importance of formylation to give tRNA(Met) an initiator identity. Surprisingly, however, recent data [Li, Y., Holmes, W. B., Appling, D. R., and RajBhandary, U. L. (2000) J. Bacteriol. 182, 2886-2892] showed that the respiratory growth of Saccharomyces cerevisiaewas not sensitive to deprivation of the mitochondrial formylase. In the present study, we report conditions of temperature or of growth medium composition in which inactivation of the formylase gene indeed impairs the growth of a S. cerevisiae haploid strain. Therefore, some selective advantage can eventually be associated to the existence of a formylating activity in the fungal mitochondrion under severe growth conditions. Finally, the specificity toward tRNA of S. cerevisiae mitochondrial formylase was studied using E. coli initiator tRNA and mutants derived from it. Like its bacterial counterpart, this formylase recognizes nucleotidic features in the acceptor stem of mitochondrial initiator tRNA. This behavior markedly distinguishes the mitochondrial formylase of yeast from that of animals. Indeed, it was shown that bovine mitochondrial formylase mainly recognizes the side chain of the esterified methionine plus a purine-pyrimidine base pair in the D-stem of tRNA [Takeuchi, N., Vial, L., Panvert, M., Schmitt, E., Watanabe, K., Mechulam, Y., and Blanquet, S. (2001) J. Biol. Chem. 276, 20064-20068]. Distinct tRNA recognition mechanisms adopted by the formylases of prokaryotic, fungal, or mammalian origins are likely to reflect coevolution of these enzymes with their tRNA substrate. Each mechanism appears well suited to an efficient selection of the substrate within the pool of all tRNAs.
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http://dx.doi.org/10.1021/bi026901xDOI Listing
February 2003

Role of protein kinase C in light adaptation of molluscan microvillar photoreceptors.

J Physiol 2002 Sep;543(Pt 2):481-94

Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA.

The mechanisms by which Ca2+ regulates light adaptation in microvillar photoreceptors remain poorly understood. Protein kinase C (PKC) is a likely candidate, both because some sub-types are activated by Ca2+ and because of its association with the macromolecular 'light-transduction complex' in Drosophila. We investigated the possible role of PKC in the modulation of the light response in molluscan photoreceptors. Western blot analysis with isoform-specific antibodies revealed the presence of PKCalpha in retinal homogenates. Immunocytochemistry in isolated cell preparations confirmed PKCalpha localization in microvillar photoreceptors, preferentially confined to the light-sensing lobe. Light stimulation induced translocation of PKCalpha immunofluorescence to the photosensitive membrane, an effect that provides independent evidence for PKC activation by illumination; a similar outcome was observed after incubation with the phorbol ester PMA. Several chemically distinct activators of PKC, such as phorbol-12-myristate-13-acetate (PMA), (-)indolactam V and 1,2,-dioctanoyl-sn-glycerol (DOG) inhibited the light response of voltage-clamped microvillar photoreceptors, but were ineffective in ciliary photoreceptors, in which light does not activate the G(q)/PLC cascade, nor elevates intracellular Ca2+. Pharmacological inhibition of PKC antagonized the desensitization produced by adapting lights and also caused a small, but consistent enhancement of basal sensitivity. These results strongly support the involvement of PKC activation in the light-dependent regulation of response sensitivity. However, unlike adapting background light or elevation of [Ca2+]i, PKC activators did not speed up the photoresponse, nor did PKC inhibitors antagonize the accelerating effects of background adaptation, suggesting that modulation of photoresponse time course may involve a separate Ca2+-dependent signal.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2290511PMC
http://dx.doi.org/10.1113/jphysiol.2002.022772DOI Listing
September 2002

Divalent cation interactions with light-dependent K channels. Kinetics of voltage-dependent block and requirement for an open pore.

J Gen Physiol 1999 Nov;114(5):653-72

Department of Physiology, Boston University School of Medicine, Boston, Massachusetts 02118, USA.

The light-dependent K conductance of hyperpolarizing Pecten photoreceptors exhibits a pronounced outward rectification that is eliminated by removal of extracellular divalent cations. The voltage-dependent block by Ca(2+) and Mg(2+) that underlies such nonlinearity was investigated. Both divalents reduce the photocurrent amplitude, the potency being significantly higher for Ca(2+) than Mg(2+) (K(1/2) approximately 16 and 61 mM, respectively, at V(m) = -30 mV). Neither cation is measurably permeant. Manipulating the concentration of permeant K ions affects the blockade, suggesting that the mechanism entails occlusion of the permeation pathway. The voltage dependency of Ca(2+) block is consistent with a single binding site located at an electrical distance of delta approximately 0.6 from the outside. Resolution of light-dependent single-channel currents under physiological conditions indicates that blockade must be slow, which prompted the use of perturbation/relaxation methods to analyze its kinetics. Voltage steps during illumination produce a distinct relaxation in the photocurrent (tau = 5-20 ms) that disappears on removal of Ca(2+) and Mg(2+) and thus reflects enhancement or relief of blockade, depending on the polarity of the stimulus. The equilibration kinetics are significantly faster with Ca(2+) than with Mg(2+), suggesting that the process is dominated by the "on" rate, perhaps because of a step requiring dehydration of the blocking ion to access the binding site. Complementary strategies were adopted to investigate the interaction between blockade and channel gating: the photocurrent decay accelerates with hyperpolarization, but the effect requires extracellular divalents. Moreover, conditioning voltage steps terminated immediately before light stimulation failed to affect the photocurrent. These observations suggest that equilibration of block at different voltages requires an open pore. Inducing channels to close during a conditioning hyperpolarization resulted in a slight delay in the rising phase of a subsequent light response; this effect can be interpreted as closure of the channel with a divalent ion trapped inside.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2230541PMC
http://dx.doi.org/10.1085/jgp.114.5.653DOI Listing
November 1999

Membrane current induced by protein kinase C activators in rhabdomeric photoreceptors: implications for visual excitation.

J Neurosci 1998 Jul;18(14):5253-63

Department of Physiology, Boston University School of Medicine, Boston, Massachusetts 02118, and Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA.

Visual excitation in rhabdomeric photoreceptors is thought to be mediated by activation of a light-regulated phospholipase C (PLC) and the consequent hydrolysis of phosphatidylinositol bisphosphate. Whereas much attention has been devoted to inositol trisphosphate (IP3) production and intracellular Ca2+ release, little is known about the possible role of the DAG branch in the generation of the light response. We have tested the effect of chemically distinct surrogates of DAG on isolated Lima photoreceptors. Application of the phorbol ester PMA (0.5-10 microM) or the alkaloid (-)-indolactam (20-100 microM) from a holding potential of -50 mV elicited an inward current, several hundred picoamperes in amplitude, accompanied by a pronounced increase in membrane conductance. The stereoisomers 4alpha-PMA and (+)-indolactam were both inactive, arguing for the specificity of the effects. Elevation of cytosolic Ca2+ by intracellular dialysis accelerated this current, whereas chelerythrine antagonized it, suggesting the involvement of PKC. The reversal potential of the membrane current induced by PKC activators was approximately +10 mV; replacement of extracellular Na with impermeant N-methyl-D-glucamine decreased its amplitude and shifted the reversal potential in the negative direction. Stimulation by PMA and (-)-indolactam was accompanied by a pronounced depression of light responsiveness; conversely, steady illumination reduced the size of the current elicited by these PKC activators. Taken together, these results support the notion that the DAG branch of the PLC cascade, in addition to its suggested participation in visual adaptation, may play a role in the activation of the photoresponse or a component thereof, probably in synergy with IP3-mediated Ca2+ release.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6793473PMC
July 1998

Activation of light-dependent K+ channels in ciliary invertebrate photoreceptors involves cGMP but not the IP3/Ca2+ cascade.

Neuron 1995 Sep;15(3):607-18

Department of Physiology, Boston University School of Medicine, Massachusetts 02118, USA.

The activation of light-dependent K+ channels in ciliary photoreceptors from Pecten was investigated using intracellular dialysis of putative messengers and modulators. Neither elevated [Ca2+] nor BAPTA changed the membrane current in the dark or the light response. IP3 and the antagonists heparin and decavanadate were similarly ineffective, indicating that in these cells the IP3/Ca2+ signaling pathway is not crucial for phototransduction. By contrast, 8-Br-cGMP and cGMP induced an outward current accompanied by an increase in membrane conductance; 8-Br-cAMP was ineffective. The identity between the cGMP-induced and the light-induced currents is suggested by the following: both are carried by K+ and blocked by 4-AP, and both show outward rectification. In addition, guanine cyclic nucleotides depressed the photoresponse and induced single-channel currents in excised patches of light-sensitive membrane. These light-dependent channels therefore appear to represent a link between the families of cyclic nucleotide-gated channels and voltage-dependent K+ channels.
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http://dx.doi.org/10.1016/0896-6273(95)90149-3DOI Listing
September 1995

Induction of voltage-dependent sodium channels by in vitro differentiation of human retinoblastoma cells.

J Neurophysiol 1993 Oct;70(4):1487-96

Department of Physiology, Boston University School of Medicine, Massachusetts 02118.

1. Neuronlike differentiation of Y-79 retinoblastoma was chemically induced in vitro, by plating the cells onto a poly-D-lysine and laminin substrate. The changes in voltage-dependent conductances after 48-72 h were examined with the whole-cell tight-seal and the perforated-patch recording techniques. 2. Although outward currents carried by potassium ions appeared qualitatively similar before and after differentiation, the depolarization-activated transient inward current displayed a pronounced acceleration of its activation and inactivation kinetics. 3. After differentiation, both the threshold of activation and the steady-state inactivation curve of the inward current are displaced in the negative direction by approximately 10-20 mV as compared with untreated cells. The current attains its peak amplitude in approximately 1 ms at maximum activating voltages, and decays within 3 ms. In contrast, in undifferentiated cells these values are on the order of 6 and 60 ms, respectively. The time to recover from inactivation is also shortened 20-fold in differentiated cells. 4. Unlike the mixed conductance of undifferentiated cells, which requires extracellular calcium, the inward current of the neuronlike differentiated cells is insensitive to manipulations of external calcium. Instead, it can be completely abolished in a reversible way by sodium removal or by micromolar concentrations of tetrodotoxin (TTX) in the bathing solution. As such, it resembles in all salient respects the voltage-dependent sodium conductance of nerve cells. 5. The fast sodium current expressed after neuronal differentiation is not the result of a progressive enhancement of an existing conductance, because no such component is discernible in undifferentiated cells. Moreover, recordings performed in cells at early stages of differentiation also failed to reveal the coexistence of the immature and the differentiated inward currents. 6. A possible account of the present observations is that the native inward current of undifferentiated Y-79 cells may correspond to a precursor form of the mature channel, and the observed developmental changes induced by chemical differentiation could be a consequence of progressive modification of the original channels, rather than expression of a separate class of proteins.
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http://dx.doi.org/10.1152/jn.1993.70.4.1487DOI Listing
October 1993

Electrical properties of Y-79 cells, a multipotent line of human retinoblastoma.

J Neurophysiol 1993 Oct;70(4):1476-86

Department of Physiology, Boston University School of Medicine, Massachusetts 02118.

1. Whole-cell and perforated-patch tight-seal recording techniques were used to characterize the voltage-dependent membrane conductances of the Y-79 cells, a human retinoblastoma line composed of pluripotential retinal precursor cells. 2. Membrane resistance and capacitance were measured under current clamp, yielding approximate average values of 1.8 G omega and 26 pF, respectively. The cells are electrically excitable, and depolarization above -20 mV triggers slow action potentials. 3. Step depolarization of the membrane under voltage clamp elicits a high-threshold transient inward current, followed by a sustained, larger outward current. The outward current is carried by potassium ions, as determined by its susceptibility to blockage by K-channel antagonists [tetraethylammonium (TEA), Cs, and 4-aminopyridine (4-AP)] and insensitivity to reduction of external chloride concentration. 4. The isolated inward current displayed some unusual properties: its amplitude is directly related to extracellular calcium concentration, and replacement of calcium by magnesium completely abolishes it. However, none of the calcium channel antagonists tested (cadmium, nickel, nifedipine, and amiloride) exerted a substantial blockage. In addition, removal of external sodium or superfusion with tetrodotoxin significantly reduce the size of this current. 5. A single voltage-dependent conductance appears to underlie the inward current, because a variety of manipulations, such as changes in the holding potential, in the extracellular concentration of calcium or sodium, or superfusion with tetrodotoxin, failed to reveal the presence of kinetically distinct components. 6. The results suggest that a single voltage-dependent conductance mechanism underlies the depolarization-activated inward current in Y-79 cells. This channel appears to be primarily permeable to calcium, but with a significant contribution by sodium ions. Its functioning appears to be modulated by extracellular calcium.
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http://dx.doi.org/10.1152/jn.1993.70.4.1476DOI Listing
October 1993

Decreased myofibrillar proteolysis after refeeding requires dietary protein or amino acids.

Am J Physiol 1987 Jul;253(1 Pt 1):E52-8

Previous studies have demonstrated that brief fasting augments and refeeding a complete diet diminishes the breakdown of myofibrillar proteins in rat skeletal muscle. The purpose of the present study was to determine which dietary component(s) was responsible for this effect and to determine the role of insulin and amino acids. Myofibrillar proteolysis was evaluated by measuring the release of 3-methylhistidine by perfused rat muscle of 1-day fasted rats and 1-day fasted rats refed for 4-24 h with a complete, protein-free, or lipid meal. For comparison, tyrosine release by perfused muscle was measured in the absence and presence of cycloheximide to evaluate net and total proteolysis, respectively. Refeeding of either diet increased plasma insulin. Despite this, myofibrillar proteolysis decreased only when protein or amino acids was included in the test meal. On the other hand, the complete or protein-free meal decreased tyrosine release in the absence but not in the presence of cycloheximide, suggesting that either diet enhanced muscle protein synthesis. Most amino acids in plasma and muscle decreased after refeeding the protein-free meal, whereas after the complete meal some amino acids in plasma and muscle increased, whereas other decreased or changed little. These results indicate that decreased myofibrillar proteolysis in muscle after refeeding of food-deprived rats requires dietary protein or amino acids. They also suggest that hormonal and/or nutritional factors other than insulin and amino acids may orchestrate this response. However, a role of amino acids cannot yet be excluded, because it is conceivable that changes in specific amino acids in plasma instead of muscle may signal diminished proteolysis.
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http://dx.doi.org/10.1152/ajpendo.1987.253.1.E52DOI Listing
July 1987
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