Publications by authors named "Zubair Hasan"

36 Publications

A 31-Year-Old Man With Respiratory Failure.

Chest 2021 Jun;159(6):e413-e415

Northwell Health System-Pulmonary & Critical Care, Manhasset, NY.

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http://dx.doi.org/10.1016/j.chest.2020.03.092DOI Listing
June 2021

Systematic review and meta-analysis of cervical metastases in oral maxillary squamous cell carcinoma.

Cancer Rep (Hoboken) 2021 May 8:e1410. Epub 2021 May 8.

University of Sydney, Camperdown, New South Wales, Australia.

Background: Management of the node-negative neck in oral maxillary squamous cell carcinoma (SCC), encompassing the hard palate and upper alveolar subsites of the oral cavity, is controversial, with no clear international consensus or recommendation regarding elective neck dissection in the absence of cervical metastases.

Aim: To assess the occult metastatic rate in patients with clinically node negative oral maxillary SCC; both as an overall metastatic rate, and a comparison of patients managed with an elective neck dissection at index surgery, compared to excision of the primary with clinical observation of the neck.

Methods And Results: A systematic review was performed by two independent investigators for studies relating to oral maxillary SCC and analysed according to PRISMA criteria. Data were extracted from Pubmed, Ovid MEDLINE, EMBASE, and SCOPUS via relevant MeSH terms. Grey literature was searched through Google Scholar and OpenGrey. Five hundred and fifty-three articles were identified on the initial search, 483 unique articles underwent screening against eligibility criteria, and 29 studies were identified for final data extraction. Incidence of occult metastases in patients with clinically node negative oral maxillary SCC was identified either on primary elective neck dissection or on routine follow up. Meta-analyses were performed. Of 553 relevant articles identified on initial search, 29 were included for analysis. The pooled overall rate of occult metastases in patients initially presenting with clinically node-negative disease was 22.2%. There is a statistically significant effect of END on decreasing regional recurrence demonstrated in this study (RR 0.36, 95% CI 0.24, 0.59).

Conclusion: The results of this systematic review and meta-analysis suggest elective neck dissection for patients presenting with hard palate or upper alveolar SCC, even in a clinically node negative neck.
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http://dx.doi.org/10.1002/cnr2.1410DOI Listing
May 2021

A Review of Acute Respiratory Distress Syndrome Management and Treatment.

Authors:
Zubair Hasan

Am J Ther 2021 Mar-Apr 01;28(2):e189-e195

Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY.

Background: Acute respiratory distress syndrome (ARDS) was first described in 1967, but its definition has evolved considerably since then. ARDS is defined as the onset of hypoxemia, tachypnea, and loss of lung compliance due to some stimulus. In the United States, the incidence of ARDS has been growing because it is being increasingly recognized. The incidence of ARDS has also gone up recently due to the COVID-19 pandemic.

Areas Of Uncertainty: To date, there is no known one treatment for ARDS. Multiple studies have looked into various causes of ARDS, pathophysiology, and ventilation and management strategies. However, there is still considerable variability in the treatment and management of these patients from institution to institution.

Data Sources: A literature search was conducted through PubMed and Google Scholar. Publications describing the epidemiology, diagnostic criteria, pathophysiology, and treatment were included in this review.

Results: The definition of ARDS has evolved over the years. The most recent and agreed upon diagnostic criteria are based on the Berlin criteria for ARDS. Management of patients with ARDS includes low tidal volume ventilation, prone ventilation, paralysis in certain patient populations, and perhaps extracorporeal membrane oxygenation (ECMO). This also applies to patients with ARDS due to COVID-19.

Conclusions: Patients with ARDS have a high mortality due to the incredibly complex disease process. Because of the complexity of ARDS, the management and treatment is equally as difficult. This article reviews some of the strategies used to date, including the role of ECMO, and includes some society recommendations. Further research must be done into which methods best guide lung ventilation in severe ARDS and patients on ECMO.
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http://dx.doi.org/10.1097/MJT.0000000000001343DOI Listing
March 2021

Physiologic Response to Angiotensin II Treatment for Coronavirus Disease 2019-Induced Vasodilatory Shock: A Retrospective Matched Cohort Study.

Crit Care Explor 2020 Oct 29;2(10):e0230. Epub 2020 Sep 29.

Sepsis Research Laboratory, Feinstein Institute for Medical Research, Manhasset, NY.

Objectives: To assess the early physiologic response to angiotensin-II treatment in patients with coronavirus disease 2019-induced respiratory failure and distributive shock.

Design: Retrospective consecutive-sample cohort study.

Setting: Three medical ICUs in New York during the coronavirus disease 2019 outbreak.

Patients: All patients were admitted to the ICU with respiratory failure and were receiving norepinephrine for distributive shock.

Interventions: The treatment groups were patients who received greater than or equal to 1 hour of angiotensin-II treatment. Time-zero was the time of angiotensin-II initiation. Controls were identified using a 2:1 hierarchical process that matched for 1) date and unit of admission; 2) specific organ support modalities; 3) age; 4) chronic lung, cardiovascular, and kidney disease; and 5) sex. Time-zero in the control group was 21 hours post vasopressor initiation, the mean duration of vasopressor therapy prior to angiotensin-II initiation in the treated group.

Measurements And Main Results: Main outcomes were trajectories of vasopressor requirements (in norepinephrine-equivalent dose) and mean arterial pressure. Additionally assessed trajectories were respiratory (Pao/Fio, Paco), metabolic (pH, creatinine), and coagulation (d-dimer) dysfunction indices after time-zero. We also recorded adverse events and clinical outcomes. Trajectories were analyzed using mixed-effects models for immediate (first 6 hr), early (48 hr), and sustained (7 d) responses. Twenty-nine patients ( = 10 treated, = 19 control) were identified. Despite matching, angiotensin-II-treated patients had markedly greater vasopressor requirements (mean: 0.489 vs 0.097 µg/kg/min), oxygenation impairment, and acidosis at time-zero. Nonetheless, angiotensin-II treatment was associated with an immediate and sustained reduction in norepinephrine-equivalent dose (6 hr model: β = -0.036 µg/kg/min/hr; 95% CI: -0.054 to -0.018 µg/kg/min/hr, =0.0002) (7 d model: β = -0.04 µg/kg/min/d, 95% CI: -0.05 to -0.03 µg/kg/min/d; = 0.0002). Compared with controls, angiotensin-II-treated patients had significantly faster improvement in mean arterial pressure, hypercapnia, acidosis, baseline-corrected creatinine, and d-dimer. Three thrombotic events occurred, all in control patients.

Conclusions: Angiotensin-II treatment for coronavirus disease 2019-induced distributive shock was associated with rapid improvement in multiple physiologic indices. Angiotensin-II in coronavirus disease 2019-induced shock warrants further study.
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http://dx.doi.org/10.1097/CCE.0000000000000230DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7523856PMC
October 2020

Preparing for the COVID-19 Pandemic: Our Experience in New York.

Chest 2020 06 25;157(6):1420-1422. Epub 2020 Mar 25.

Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, Hempstead, NY.

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http://dx.doi.org/10.1016/j.chest.2020.03.027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7152895PMC
June 2020

Buccal space tumours.

Auris Nasus Larynx 2019 Apr 18;46(2):160-166. Epub 2018 Jul 18.

Department of Otolaryngology-Head & Neck Surgery, Westmead Hospital, Westmead, Australia.

Objective: To review the available literature as it pertains to the buccal space with a specific focus on the pathologies encountered within this space. Clinical presentation, investigations, and surgical approaches to the region are also reviewed.

Methods: A systematic review of the available literature was performed on buccal space tumours from 1980 to 2017. Data was extracted on clinical presentation, investigations and surgical approaches to the buccal space. The pathologies encountered in the buccal space were reviewed and presented.

Results: Forty-nine unique articles were reviewed, with a total 217 patients. The age of the patients ranged from 0 to 83 with a mean age of 45.8. A total of 51 pathologies were reported. The majority of these were vascular and salivary gland pathologies. The majority of salivary gland neoplasms were malignant. However a wide variety of benign and malignant soft tissue tumours were also reported to occur in this region.

Conclusions: The buccal space is a small and complex region with a variety of pathologies occurring within it. This review clarifies the differential diagnosis of a mass which presents in this area and the pathologies which occur within it.
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http://dx.doi.org/10.1016/j.anl.2018.06.011DOI Listing
April 2019

Cervical necrotizing fasciitis: Systematic review and analysis of 1235 reported cases from the literature.

Head Neck 2018 09 22;40(9):2094-2102. Epub 2018 Jun 22.

Department of Otolaryngology, Head and Neck Surgery, Westmead Hospital, Sydney, Australia.

Background: Cervical necrotizing fasciitis is a progressive soft tissue infection with significant morbidity and mortality.

Methods: A case review of cervical necrotizing fasciitis managed at our institution (2007-2017) and a systematic review of PubMed, MEDLINE, and EMBASE databases using the algorithm "(cervical OR neck) AND necrotizing fasciitis."

Results: There were 1235 cases from 207 articles which were included in our clinical review. Mean age for cervical necrotizing fasciitis was 49.1 years (64.23% men). Etiology was odontogenic (47.04%), pharyngolaryngeal (28.34%), or tonsillar/peritonsillar (6.07%). There were 2 ± 0.98 organisms identified per patient; streptococci (61.22%), staphylococci (18.09%), and prevotella (10.87%). There were 2.5 ± 3.22 surgical debridements undertaken. Descending necrotizing mediastinitis occurred in 31.56% of patients. Mean length of stay in the hospital was 29.28 days and overall mortality was 13.36%.

Conclusion: Physicians and surgeons must be vigilant of the diagnosis of cervical necrotizing fasciitis as early clinical findings may be subtle and prompt identification to facilitate aggressive intervention is required to preclude catastrophic local and systemic morbidity and mortality.
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http://dx.doi.org/10.1002/hed.25184DOI Listing
September 2018

Beyond the Beck's Triad: The Use of Point-of-Care Ultrasound for Diagnosis and Treatment of Shock.

Ann Am Thorac Soc 2018 05;15(5):637-640

Division of Pulmonary, Critical Care, and Sleep Medicine, Hofstra Northwell School of Medicine, Northwell Health, New Hyde Park, New York.

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http://dx.doi.org/10.1513/AnnalsATS.201709-739CCDOI Listing
May 2018

A 70-Year-Old Woman With Recent Intracranial Hemorrhage Presenting With Profound Shock.

Chest 2018 02;153(2):e25-e27

Hofstra Northwell School of Medicine, New Hyde Park, NY.

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http://dx.doi.org/10.1016/j.chest.2017.08.1180DOI Listing
February 2018

Allelopathic interference of alfalfa (Medicago sativa L.) genotypes to annual ryegrass (Lolium rigidum).

J Plant Res 2017 Jul 22;130(4):647-658. Epub 2017 Mar 22.

South Australian Research and Development Institute, Waite Campus, Adelaide, SA, 5001, Australia.

Alfalfa (Medicago sativa L.) genotypes at varying densities were investigated for allelopathic impact using annual ryegrass (Lolium rigidum) as the target species in a laboratory bioassay. Three densities (15, 30, and 50 seedlings/beaker) and 40 alfalfa genotypes were evaluated by the equal compartment agar method (ECAM). Alfalfa genotypes displayed a range of allelopathic interference in ryegrass seedlings, reducing root length from 5 to 65%. The growth of ryegrass decreased in response to increasing density of alfalfa seedlings. At the lowest density, Q75 and Titan9 were the least allelopathic genotypes. An overall inhibition index was calculated to rank each alfalfa genotype. Reduction in seed germination of annual ryegrass occurred in the presence of several alfalfa genotypes including Force 10, Haymaster7 and SARDI Five. A comprehensive metabolomic analysis using Quadruple Time of Flight (Q-TOF), was conducted to compare six alfalfa genotypes. Variation in chemical compounds was found between alfalfa root extracts and exudates and also between genotypes. Further individual compound assessments and quantitative study at greater chemical concentrations are needed to clarify the allelopathic activity. Considerable genetic variation exists among alfalfa genotypes for allelopathic activity creating the opportunity for its use in weed suppression through selection.
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http://dx.doi.org/10.1007/s10265-017-0921-9DOI Listing
July 2017

Adsorptive Removal of Artificial Sweeteners from Water Using Metal-Organic Frameworks Functionalized with Urea or Melamine.

ACS Appl Mater Interfaces 2016 Nov 20;8(43):29799-29807. Epub 2016 Oct 20.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University , Daegu 702-701, Republic of Korea.

A highly porous metal-organic framework (MOF), MIL-101, was modified to introduce urea or melamine via grafting on open metal sites of the MOF. Adsorptive removal of three artificial sweeteners (ASWs) was studied using the MOFs, with or without modifications (including nitration), and activated carbon (AC). The adsorbed quantities (based on the weight of the adsorbent) of saccharin (SAC) under various conditions decreased in the order urea-MIL-101 > melamine-MIL-101 > MIL-101 > AC > ON-MIL-101; however, the quantities based on unit surface area are in the order melamine-MIL-101 > urea-MIL-101 > MIL-101 > ON-MIL-101. Similar ASWs [acesulfame (ACE) and cyclamate (CYC)] showed the same tendency. The mechanism for very favorable adsorption of SAC, ACE, and CYC over urea- and melamine-MIL-101 could be explained by H-bonding on the basis of the contents of -NH groups on the MOFs and the adsorption results under a wide range of pH values. Moreover, the direction of H-bonding could be clearly defined (H acceptor: ASWs; H donor: MOFs). Urea-MIL-101 and melamine-MIL-101 could be suggested as competitive adsorbents for organic contaminants (such as ASWs) with electronegative atoms, considering their high adsorption capacity (for example, urea-MIL-101 had 2.3 times the SAC adsorption of AC) and ready regeneration.
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http://dx.doi.org/10.1021/acsami.6b11115DOI Listing
November 2016

Aromatization of Ethanol Over Desilicated ZSM-5 Zeolites: Effect of Pore Size in the Mesoporous Region.

J Nanosci Nanotechnol 2016 May;16(5):4377-85

Mesoporous ZSM-5 zeolites were obtained from microporous ZSM-5 by desilication using aqueous NaOH solutions, and their catalytic activity in the aromatization of ethanol was investigated in order to understand the effects of pore size, in the mesoporous region, on the product distribution and stability of the catalysts. Mesopores generally enhanced the selectivities towards aromatics and stability for aromatization. Mesopores with a maximum pore diameter of around 13 nm were the most effective in the aromatization process (especially for benzene and toluene), suggesting that pore-diameter optimization is necessary for efficient catalysis such as aromatization.
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http://dx.doi.org/10.1166/jnn.2016.10990DOI Listing
May 2016

Bilateral stage I chronic maxillary atelectasis: A case report.

Int J Surg Case Rep 2016 16;26:53-6. Epub 2016 Jul 16.

Department of Otolaryngology, Head and Neck Surgery, Westmead Hospital, Sydney, Australia; University of Sydney, Sydney, Australia.

Introduction: Chronic maxillary atelectasis (CMA) is a rare acquired condition of persistent and progressive reduction in maxillary sinus volume and antral wall collapse secondary to ostiomeatal obstruction and development of negative intra-sinus pressure gradients.

Case Presentation: A 32-year old male was referred with a 6 week history of persistent and worsening sinonasal symptoms, following a significant upper respiratory tract infection. Imaging confirmed bilateral stage I CMA and successful treatment entailed bilateral endoscopic uncinectomy and maxillary antrostomy.

Discussion: Review of the literature has demonstrated CMA to describe an all-encompassing disease process of ostiomeatal obstruction and atelectatic maxillary sinus remodelling that overcomes early variations in taxonomy ('silent sinus syndrome', 'imploding antrum syndrome', 'acquired maxillary sinus hypoplasia') and inconsistencies in reporting. Unilateral CMA is well documented, however a systematic search of the literature reveals only six bilateral cases. To the best of our knowledge, this is the first individual report of bilateral stage I CMA in which the inciting event is established and a uniquely rapid progress of disease followed.

Conclusion: The present literature regarding CMA is incomplete and further investigation is required to provide greater insight into its aetiology and pathogenesis. Minimally invasive endoscopic approaches can be employed to re-establish aeration to the affected maxillary sinus for symptomatic relief, to halt disease progression and facilitate antral remodelling and sinus re-expansion.
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http://dx.doi.org/10.1016/j.ijscr.2016.07.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4961494PMC
September 2016

Neuroendocrine Adenoma of the Middle Ear: A Rare Histopathological Diagnosis.

Case Rep Otolaryngol 2016 27;2016:9834750. Epub 2016 Jun 27.

Department of Otolaryngology-Head & Neck Surgery, Westmead Hospital, Sydney, NSW 2153, Australia.

Neuroendocrine tumours occur throughout the body but are rare in the head and neck region and particularly rare in the middle ear. Clinical findings are often nonspecific and therefore pose a diagnostic challenge. Furthermore, the nomenclature of neuroendocrine tumours of the middle ear is historically controversial. Herein a case is presented of a middle ear adenoma in a 33-year-old patient who presented with otalgia, hearing loss, and facial nerve palsy. A brief discussion is included regarding the histopathological features of middle ear adenomas and seeks to clarify the correct nomenclature for these tumours.
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http://dx.doi.org/10.1155/2016/9834750DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939355PMC
July 2016

Preparation of Calcined Zirconia-Carbon Composite from Metal Organic Frameworks and Its Application to Adsorption of Crystal Violet and Salicylic Acid.

Materials (Basel) 2016 Mar 31;9(4). Epub 2016 Mar 31.

Department of Environment and Energy, Sejong University, Seoul 143-747, Korea.

Zirconia-carbon (ZC) composites were prepared via calcination of Zr-based metal organic frameworks, UiO-66 and amino-functionalized UiO-66, under N₂ atmosphere. The prepared composites were characterized using a series of instrumental analyses. The surface area of the ZC composites increased with the increase of calcination temperature, with the formation of a graphite oxide phase observed at 900 °C. The composites were used for adsorptive removal of a dye (crystal violet, CV) and a pharmaceutical and personal care product (salicylic acid, SA). The increase of the calcination temperature resulted in enhanced adsorption capability of the composites toward CV. The composite calcined at 900 °C exhibited a maximum uptake of 243 mg·g, which was much greater than that by a commercial activated carbon. The composite was also effective in SA adsorption (102 mg·g), and N-functionalization of the composite further enhanced its adsorption capability (109 mg·g). CV adsorption was weakly influenced by solution pH, but was more dependent on the surface area and pore volume of the ZC composite. Meanwhile, SA adsorption showed strong pH dependence, which implies an active role of electrostatic interactions in the adsorption process. Base-base repulsion and hydrogen bonding are also suggested to influence the adsorption of CV and SA, especially for the N-functionalized composite.
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http://dx.doi.org/10.3390/ma9040261DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5502925PMC
March 2016

Ionic [email protected] prepared via the ship-in-bottle technique: remarkable adsorbents for the removal of benzothiophene from liquid fuel.

Chem Commun (Camb) 2016 Feb 8;52(12):2561-4. Epub 2016 Jan 8.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

Ionic liquids (ILs) were synthesized inside a porous metal-organic framework (MIL-101) via a ship-in-bottle (SIB) technique. Unlike previously reported IL-incorporated MIL-101s, [email protected] prepared by the SIB approach was very stable over several cycles for the liquid phase adsorption of benzothiophene from liquid fuel.
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http://dx.doi.org/10.1039/c5cc08896hDOI Listing
February 2016

Facile method to disperse nonporous metal organic frameworks: composite formation with a porous metal organic framework and application in adsorptive desulfurization.

ACS Appl Mater Interfaces 2015 May 7;7(19):10429-35. Epub 2015 May 7.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

It is generally not easy to utilize nonporous metal organic frameworks (MOFs) with a large crystal size (especially for catalysis or adsorption) because their surface area is low and the majority of the active sites exist inside the MOFs. Composing with porous materials may be one way to disperse the nonporous materials. In this study, a nonporous/nonsoluble MOF (in which the particle size was much larger than the cavity size of the porous MOFs) containing Cu(I) ((Cu2(pyz)2(SO4)(H2O)2)n, denoted as CP) was composed with typical porous MOFs such as MIL100(Fe) (iron-benzenetricarboxylate) and CuBTC (cupper-benzenetricarboxylate). The Cu(I) species of the nonporous MOF was effectively utilized for the adsorptive desulfurization (ADS) of model fuel. Even though the porosities of the composed MOFs decreased as the content of CP increased, the adsorption capacity increased as the content of CP increased (up to a certain content). Considering the negligible capacity of CP for ADS, the enhanced adsorption capacity may be a result of the well-dispersed Cu(I), which is known to be beneficial for ADS via π-complexation. The dispersed CP was also observed by transmission electron microscopy mapping. Therefore, composing a nonporous MOF with porous MOF is a new and facile way to disperse/utilize the active sites of a nonporous MOF.
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http://dx.doi.org/10.1021/acsami.5b01642DOI Listing
May 2015

Removal of hazardous organics from water using metal-organic frameworks (MOFs): plausible mechanisms for selective adsorptions.

J Hazard Mater 2015 28;283:329-39. Epub 2014 Sep 28.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea. Electronic address:

Provision of clean water is one of the most important issues worldwide because of continuing economic development and the steady increase in the global population. However, clean water resources are decreasing everyday, because of contamination with various pollutants including organic chemicals. Pharmaceutical and personal care products, herbicides/pesticides, dyes, phenolics, and aromatics (from sources such as spilled oil) are typical organics that should be removed from water. Because of their huge porosities, designable pore structures, and facile modification, metal-organic frameworks (MOFs) are used in various adsorption, separation, storage, and delivery applications. In this review, the adsorptive purifications of contaminated water with MOFs are discussed, in order to understand possible applications of MOFs in clean water provision. More importantly, plausible adsorption or interaction mechanisms and selective adsorptions are summarized. The mechanisms of interactions such as electrostatic interaction, acid-base interaction, hydrogen bonding, π-π stacking/interaction, and hydrophobic interaction are discussed for the selective adsorption of organics over MOFs. The adsorption mechanisms will be very helpful not only for understanding adsorptions but also for applications of adsorptions in selective removal, storage, delivery and so on.
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http://dx.doi.org/10.1016/j.jhazmat.2014.09.046DOI Listing
February 2016

Effect of central metal ions of analogous metal-organic frameworks on adsorption of organoarsenic compounds from water: plausible mechanism of adsorption and water purification.

Chemistry 2015 Jan 8;21(1):347-54. Epub 2014 Oct 8.

Department of Chemistry and Green-Nano Materials Research Centre, Kyungpook National University, Daegu 702-701 (Republic of Korea), Fax: (+82) 53-950-6330.

The adsorptive removal of organoarsenic compounds such as p-arsanilic acid (ASA) and roxarsone (ROX) from water using metal-organic frameworks (MOFs) has been investigated for the first time. A MOF, iron benzenetricarboxylate (also called MIL-100-Fe) exhibits a much higher adsorption capacity for ASA and ROX than activated carbon, zeolite (HY), goethite, and other MOFs. The adsorption of ASA and ROX over MIL-100-Fe is also much more rapid than that over activated carbon. Moreover, the used MIL-100-Fe can be recycled by simply washing with acidic ethanol. Therefore, it is determined that a MOF such as MIL-100-Fe can be used to remove organoarsenic compounds from contaminated water because of its high adsorption capacity, rapid adsorption, and ready regeneration. Moreover, only one of three analogous MIL-100 species (MIL-100-Fe, rather than MIL-100-Al or MIL-100-Cr) can effectively remove the organoarsenic compounds. This selective and high adsorption over MIL-100-Fe, different from other analogous MIL-100 species, can be explained (through calculations) by the facile desorption of water from MIL-100-Fe as well as the large (absolute value) replacement energy (difference between the adsorption energies of the organoarsenic compounds and water) exhibited by MIL-100-Fe. A plausible adsorption/desorption mechanism is proposed based on the surface charge of the MOFs, FTIR results, calculations, and the reactivation results with respect to the solvents used in the experiments.
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http://dx.doi.org/10.1002/chem.201404658DOI Listing
January 2015

Adsorption and removal of phthalic acid and diethyl phthalate from water with zeolitic imidazolate and metal-organic frameworks.

J Hazard Mater 2015 Jan 31;282:194-200. Epub 2014 Mar 31.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Sankyuck-Dong, Daegu 702-701, Republic of Korea. Electronic address:

ZIF-8 (zinc-methylimidazolate framework-8), one of the zeolitic imidazolate frameworks (ZIFs), has been used for the removal of phthalic acid (H2-PA) and diethyl phthalate (DEP) from aqueous solutions via adsorption. The adsorption capacity of the ZIF-8 for H2-PA was much higher than that of a commercial activated carbon or other typical metal-organic frameworks (MOFs). Because the surface area and pore volume of the adsorbents showed no favorable effect on the adsorption of H2-PA, the remarkable adsorption with ZIF-8 suggests a specific favorable interaction (electrostatic interaction) between the positively charged surface of ZIF-8 and the negatively charged PA anions. In addition, acid-base interactions also have a favorable contribution in the adsorption of H2-PA, based on the adsorptive performances of pristine and amino-functionalized MOFs and adsorption over ZIF-8 at acidic condition (pH=3.5). The reusability of ZIF-8 was also demonstrated after simple washing with methanol. On the other hand, ZIF-8 was not effective in adsorbing DEP probably because of little charge of DEP in a water solution.
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http://dx.doi.org/10.1016/j.jhazmat.2014.03.047DOI Listing
January 2015

Ionic liquids supported on metal-organic frameworks: remarkable adsorbents for adsorptive desulfurization.

Chemistry 2014 Jan 20;20(2):376-80. Epub 2013 Dec 20.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701 (Korea), Fax: (+82) 53-950-6330.

Acidic ionic-liquids (IL) supported on metal-organic frameworks (MOFs) have been shown to be beneficial for adsorptive desulfurization. A remarkable improvement in the adsorption capacity (ca. 71%) was observed in for ILs supported on MIL-101 compared with virgin MIL-101. The improved adsorptive performance might be explained by the acid-base interactions between the acidic ionic liquid and basic benzothiophene (BT). Moreover, from this study, it can be suggested that porous MOFs, supported with ionic liquids, may introduce a new class of highly porous adsorbents for the efficient adsorption of various compounds.
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http://dx.doi.org/10.1002/chem.201304291DOI Listing
January 2014

Adsorptive removal of bisphenol-A from water with a metal-organic framework, a porous chromium-benzenedicarboxylate.

J Nanosci Nanotechnol 2013 Apr;13(4):2789-94

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

Adsorptive removal of bisphenol-A (BPA) using a MOF, Cr-benzenedicarboxylate (MIL-53), has been studied to understand the applicability of MOFs for the removal of hazardous endocrine disturbing chemicals from water. MIL-53 shows very fast adsorption in an hour and the adsorption capacity of MIL-53 is higher than that of activated carbon. Importantly, the adsorption of BPA over MIL-53 is very favorable especially at very low concentrations of BPA. Therefore, MOFs such as MIL-53 can be one of adsorbents that may be used in the adsorptive removal of BPA from contaminated water.
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http://dx.doi.org/10.1166/jnn.2013.7411DOI Listing
April 2013

Options for configuring the scapular free flap in maxillary, mandibular, and calvarial reconstruction.

Plast Reconstr Surg 2013 Sep;132(3):645-655

Sydney, Australia; and Houston, Texas From Blacktown Hospital; the Department of Head and Neck Surgery, The Sydney Head and Neck Cancer Institute, Royal Prince Alfred Hospital; the Department of Plastic Surgery, University of Texas M. D. Anderson Cancer Center; and the Department of Head and Neck Surgery, Liverpool Hospital.

Background: A number of microvascular free-flap tissue transfer techniques exist for reconstruction of head and neck defects. The scapular free flap is a versatile option that can be used for a wide variety of defects in this complex region.

Methods: A series of 42 free flaps from 41 patients was retrospectively identified from the senior author's (J.R.C.) [corrected] database between 2006 and 2012. Information regarding patient demographics, indication for surgery, type of flap, reconstructive methods, complications, and prosthodontic outcome were reviewed and have been described.

Result: A wide range of defects were reconstructed using the scapular free flap. Of the 42 reconstructions, 24 were for mandibular, 13 were for maxillary, and five were for calvarial reconstruction. The patients' ages ranged from 28 to 82 years, with a median of 70 years. Dental restoration was achieved in eight patients with maxillary reconstruction and two patients with mandibular reconstruction. There were 11 major complications, including two total flap failures.

Conclusions: The authors have found the scapular free flap to be a reliable, robust, and versatile flap that provides an unparalleled range of reconstructive options, with minimal donor-site morbidity. Thus, the authors believe that the scapular free flap is a valuable reconstructive option for patients with complex head and neck defects and in patients in whom comorbid disease contraindicates the use of the fibular free flap.
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http://dx.doi.org/10.1097/PRS.0b013e31829acf5cDOI Listing
September 2013

Adsorptive denitrogenation of model fuels with porous metal-organic framework (MOF) MIL-101 impregnated with phosphotungstic acid: effect of acid site inclusion.

J Hazard Mater 2013 Apr 24;250-251:37-44. Epub 2013 Jan 24.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

A metal-organic framework (MOF) MIL-101 was impregnated with phosphotungstic acid (PWA) and used as an adsorbent in liquid phase adsorption of nitrogen-containing compounds (NCCs) from a model fuel. The model fuel contained one sulfur-containing compound (SCC), benzothiophene (BT); one basic NCC, quinoline (QUI); and one neutral NCC, indole (IND). In both MIL-101 and PWA-impregnated MIL-101s, NCC adsorption selectivity was very high compared to the SCC selectivity. Additionally, the adsorption capacity of basic QUI increased by 20% with only 1% PWA impregnation in MIL-101. The adsorption of a neutral compound, IND, was slightly reduced with PWA impregnation in the MOF. The adsorption capacity/selectivity can be remarkably improved by a slight modification of MOFs, for example, to impart acidity. The MOF impregnated with PWA may be very interesting in commercial denitrogenation, especially for coal-derived fuels which contain mainly basic NCCs, by adsorption since the selectivity for NCCs (compared to SCCs) over the adsorbent is very high and the adsorbent can be reused many times.
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http://dx.doi.org/10.1016/j.jhazmat.2013.01.024DOI Listing
April 2013

Adsorptive removal of hazardous materials using metal-organic frameworks (MOFs): a review.

J Hazard Mater 2013 Jan 13;244-245:444-56. Epub 2012 Nov 13.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

Efficient removal of hazardous materials from the environment has become an important issue from a biological and environmental standpoint. Adsorptive removal of toxic components from fuel, waste-water or air is one of the most attractive approaches for cleaning technologies. Recently, porous metal-organic framework (MOF) materials have been very promising in the adsorption/separation of various liquids and gases due to their unique characteristics. This review summarizes the recent literatures on the adsorptive removal of various hazardous compounds mainly from fuel, water, and air by virgin or modified MOF materials. Possible interactions between the adsorbates and active adsorption sites of the MOFs will be also discussed to understand the adsorption mechanism. Most of the observed results can be explained with the following mechanisms: (1) adsorption onto a coordinatively unsaturated site, (2) adsorption via acid-base interaction, (3) adsorption via π-complex formation, (4) adsorption via hydrogen bonding, (5) adsorption via electrostatic interaction, and (6) adsorption based on the breathing properties of some MOFs and so on.
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http://dx.doi.org/10.1016/j.jhazmat.2012.11.011DOI Listing
January 2013

Adsorptive removal of naproxen and clofibric acid from water using metal-organic frameworks.

J Hazard Mater 2012 Mar 10;209-210:151-7. Epub 2012 Jan 10.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

Adsorptive removal of naproxen and clofibric acid, two typical PPCPs (pharmaceuticals and personal care products), has been studied using metal-organic frameworks (MOFs) for the first time. The removal efficiency decreases in the order of MIL-101>MIL-100-Fe>activated carbon both in adsorption rate and adsorption capacity. The adsorption kinetics and capacity of PPCPs generally depend on the average pore size and surface area (or pore volume), respectively, of the adsorbents. The adsorption mechanism may be explained with a simple electrostatic interaction between PPCPs and the adsorbent. Finally, it can be suggested that MOFs having high porosity and large pore size can be potential adsorbents to remove harmful PPCPs in contaminated water.
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http://dx.doi.org/10.1016/j.jhazmat.2012.01.005DOI Listing
March 2012

Oxidative desulfurization of benzothiophene and thiophene with WOx/ZrO2 catalysts: effect of calcination temperature of catalysts.

J Hazard Mater 2012 Feb 29;205-206:216-21. Epub 2011 Dec 29.

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, Daegu 702-701, Republic of Korea.

Oxidative desulfurization (ODS) of model fuel containing benzothiophene (BT) or thiophene (Th) has been carried out with WO(x)/ZrO2 catalyst, which was calcined at various temperatures. Based on the conversion of BT in the model fuel, it can be shown that the optimum calcination temperature of WOx/ZrO2 catalyst is around 700 °C. The most active catalyst is composed of tetragonal zirconia (ZrO2) with well dispersed polyoxotungstate species and it is necessary to minimize the contents of the crystalline WO3 and monoclinic ZrO2 for a high BT conversion. The oxidation rate was interpreted with the first-order kinetics, and it demonstrated the importance of electron density since the kinetic constant for BT was higher than that for Th even though the BT is larger than Th in size. A WOx/ZrO2 catalyst, treated suitably, can be used as a reusable active catalyst in the ODS.
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http://dx.doi.org/10.1016/j.jhazmat.2011.12.059DOI Listing
February 2012

Anti-HCV antibody positivity of various sections of Pakistani patients.

J Coll Physicians Surg Pak 2009 Nov;19(11):737-41

Department of Medicine, Rawalpindi Medical College, Rawal Road, Rawalpindi.

Objective: To determine the anti-HCV antibody status of various sections of the Pakistani population and patients as reported in various Pakistani studies.

Study Design: A meta-analysis.

Place And Duration Of Study: Department of Medicine, Rawalpindi Medical College and Allied Hospitals, Rawalpindi, from July 2007 to July 2008.

Methodology: Data pertaining to anti-HCV antibody status of various sections of the Pakistani population and patients was collected from studies published till July 2008. To note anti-HCV antibody status, 15 groups of subjects like liver disease patients, general blood donors, adult screening, and community prevalence etc. were identified. The frequency of total and anti-HCV antibody positive subjects of each group was noted. Chi2 was used as test of significance for comparison wherever appropriate.

Results: Data from 183 studies was collected; 1004391 subjects anti-HCV antibody status was retrieved. 4.27% (n=42982) of these were anti-HCV antibody positive. Major bulk of patients with liver disease (56.9%), 2.71% of general and 10.39% of professional blood donors groups were positive, (p < 0.05). Positivity in community and adult screening was 11.52 and 6.29% respectively.

Conclusion: According to the studies in consideration; 2.71% of Pakistani general blood donors and major bulk of liver disease patients are anti-HCV positive. Community based anti-HCV positivity is 11.52%.
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http://dx.doi.org/11.2009/JCPSP.737741DOI Listing
November 2009

Bouveret's syndrome.

J Coll Physicians Surg Pak 2008 Jul;18(7):435-7

Department of General Surgery, PAEC General Hospital, Islamabad.

Gastric Outlet Obstruction (GOO) due to impaction of a gallstone in the duodenum after migration through a bilioduodenal fistula is known as Bouveret's syndrome. Its clinical symptoms are entirely vague and nonspecific. Because of its rarity, insidiousness and unpredictable symptomatology, Bouveret's syndrome is never thought of in the differential diagnosis as aetiology of gastric outlet obstruction. Recent advances in fiberoptics technology, advent of modern imaging modalities and minimally-invasive techniques like endoscopy and laparoscopy has brought a great revolution in the management of Bouveret's syndrome and have tremendously decreased morbidity and mortality associated with this rare clinical entity.
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http://dx.doi.org/07.2008/JCPSP.435437DOI Listing
July 2008