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Optimal Cefazolin Prophylactic Dosing for Bariatric Surgery: No Need for Higher Doses or Intraoperative Redosing
Chen, Xing; Brathwaite, Collin E M; Barkan, Alexander; Hall, Keneth; Chu, Gloria; Cherasard, Patricia; Wang, Shan; Nicolau, David P; Islam, Shahidul; Cunha, Burke A
PURPOSE:The goal of this pharmacokinetic (PK) study was to evaluate whether a single 2-g prophylactic dose of cefazolin given (IV) bolus provides effective protective cefazolin levels for prophylaxis against methicillin-sensitive S. aureus (MSSA), the primary skin pathogen in bariatric surgery. MATERIALS AND METHODS:Thirty-seven patients having gastric bypass or sleeve gastrectomy received cefazolin 2-g preoperative prophylaxis. Serum, subcutaneous adipose tissue, and deep peri-gastric adipose tissue specimens were collected at incision and before skin closure. Cefazolin concentrations in serum and adipose tissue were determined by high-performance liquid chromatography. RESULTS:Penetration of cefazolin, a water soluble antibiotic, into adipose tissue was only 6-8Â % of simultaneous serum levels. However, cefazolin tissue concentrations in all adipose tissue specimens, exceeded mean MIC for MSSA. CONCLUSIONS:not dose-dependent. Extremely high-dosed cefazolin, i.e., 3 or 4Â g is excessive and unnecessary for bariatric surgery prophylaxis. A single cefazolin 2 g preoperative dose also eliminates the need for intraoperative redosing at 4Â h.
PMID: 27520693
ISSN: 1708-0428
CID: 3433882
IR and the Sunshine Act: Two-Year Analysis of the Open Payments Database and Comparison with Related Specialties
Baadh, Amanjit S; Baadh, Palvir K; Islam, Shahidul; Katz, Douglas S
PURPOSE/OBJECTIVE:To characterize medical industry-based payments made to US-based interventional radiology (IR) physicians, identify trends in compensation, and compare their payment profile with those of other related specialties, including vascular surgery (VS) and interventional cardiology (IC). Payments made to orthopedic surgery (OS) physicians are reported as a historical control. MATERIALS AND METHODS/METHODS:For each group, the total payment number, amount, and mean and median numbers and amounts were calculated. The data were then reanalyzed after correcting for statistical outliers. For IR, VS, and IC, leading industry sponsors, payment amount, and differences in payments from 2013 to 2014 were highlighted. Payments to IR were grouped by category and geographic location. The Kruskal-Wallis test was used for statistical analysis. RESULTS:A total of $26,857,622 went to 1,831 IR physicians, representing 70.9% of active IR physicians, and the corrected mean payment was $597 ± 832.2 (standard deviation). The respective values were $18,861,041, 3,383, 80.6%, and $851.59 for VS; $32,008,213, 7,939, 78.6%, and $417.16 for IC; and $357,528,020, 21,829, 77.8%, and $598.48 for OS. OS had the largest number of payments (295,465 vs 24,246 for IR, 84,635 for VS, and 160,443 for IC) and greatest total payment amount. VS had a significantly higher corrected median payment amount ($463; P < .0001) than IR ($214) and IC ($99). Covidien and Sirtex Medical were the leading industry sponsors to IR, and 64.6% of IR payments were compensation for services other than consulting. There was no significant difference in median payment received per geographic region (P = .32). CONCLUSIONS:OS received the largest number and total payment amount, and VS received a significantly greater corrected median payment amount, versus IR and IC. As the Open Payments program continues to be implemented, it remains to be seen how this information will affect relationships among physicians, patients, and industry.
PMID: 27993504
ISSN: 1535-7732
CID: 3003072
Pentoxifylline inhibits lipopolysaccharide-induced inflammatory mediators in human second trimester placenta explants
Speer, Esther M; Lin, Xinhua; Murthy, Amitasrigowri; Hou, Wei; Islam, Shahidul; Hanna, Nazeeh
BACKGROUND: Intrauterine infection and inflammation during pregnancy, which leads to up-regulation of inflammatory cytokines and prostaglandin synthesis, has been implicated in the pathogenesis of preterm delivery and other pregnancy complications. Effective preventive and therapeutic strategies to reduce these outcomes are lacking to date. Pentoxifylline (PTX) is a non-specific phosphodiesterase inhibitor which raises intracellular cyclic adenosine monophosphate and decreases production of pro-inflammatory mediators while enhancing anti-inflammatory cytokines. We hypothesized that pentoxifylline will decrease lipopolysaccharide (LPS)-induced pro-inflammatory cytokines production in human placental explants. METHODS: Placental explants derived from normal second trimester human placentas were treated with PTX, stimulated with LPS and cultured at 37 degrees C in 5% CO2. Conditioned media were assayed for pro- and anti-inflammatory mediators with multiplex immunoassays or ELISA, and explant tissues for mRNA with real time PCR. Means of PTX-treated and untreated samples were compared using paired t tests and Wilcoxon-signed rank tests. RESULTS: PTX preferentially inhibited placental expression and production of LPS-induced pro-inflammatory cytokines including TNF-alpha (25461 vs. 1908 pg/ml, p < 0.001), IL-1beta (2921 vs. 1067 pg/ml, p < 0.001) and IFN-gamma (2190 vs 427 pg/ml, p < 0.001) with relative preservation of anti-inflammatory mediators. The suppressive effects on LPS-induced placental inflammation were independent of the timing of PTX administration in relation to LPS-induced stimulation. CONCLUSION: Our study suggests that PTX attenuates the LPS-induced pro-inflammatory milieu in human placental explants. We speculate that PTX may have utility as a candidate anti-inflammatory agent for prophylaxis and/or treatment of human placental inflammation.
PMID: 28962697
ISSN: 1532-3102
CID: 2717442
Cryo-EM Structures of the Magnesium Channel CorA Reveal Symmetry Break upon Gating
Matthies, Doreen; Dalmas, Olivier; Borgnia, Mario J; Dominik, Pawel K; Merk, Alan; Rao, Prashant; Reddy, Bharat G; Islam, Shahidul; Bartesaghi, Alberto; Perozo, Eduardo; Subramaniam, Sriram
CorA, the major Mg(2+) uptake system in prokaryotes, is gated by intracellular Mg(2+) (KD ∼ 1-2 mM). X-ray crystallographic studies of CorA show similar conformations under Mg(2+)-bound and Mg(2+)-free conditions, but EPR spectroscopic studies reveal large Mg(2+)-driven quaternary conformational changes. Here, we determined cryo-EM structures of CorA in the Mg(2+)-bound closed conformation and in two open Mg(2+)-free states at resolutions of 3.8, 7.1, and 7.1 Å, respectively. In the absence of bound Mg(2+), four of the five subunits are displaced to variable extents (∼ 10-25 Å) by hinge-like motions as large as ∼ 35° at the stalk helix. The transition between a single 5-fold symmetric closed state and an ensemble of low Mg(2+), open, asymmetric conformational states is, thus, the key structural signature of CorA gating. This mechanism is likely to apply to other structurally similar divalent ion channels.
PMID: 26871634
ISSN: 1097-4172
CID: 5034112
GATA-3 expression is not associated with complete pathological response in triple negative breast cancer patients treated with neoadjuvant chemotherapy
Wasserman, Jason K; Williams, Phillip A; Islam, Shahidul; Robertson, Susan J
OBJECTIVE:The prognosis for patients with triple negative breast cancer (TNBC) is poor, however, a subset will demonstrate complete pathological response (pCR) to chemotherapy. GATA-3 and AR may be a negative predictors for pCR although it is unclear if these results apply to TNBC. METHODS:Patients diagnosed with TNBC and treated with neoadjuvant chemotherapy were identified. Immunohistochemistry was performed for GATA-3 and AR. Both were scored using a composite of staining intensity and percentage cells stained. The primary outcome was pCR. RESULTS:Twenty-four patients were included and 7 achieved pCR. There was no difference in the pre-chemotherapy tumor size (44±28mm vs. 54±30mm; p=0.764) or lymph node status (86% vs. 71%; p=0.629) between patients with and without pCR. GATA-3 expression was present in 20 cases (83%) while AR was present in 6 cases (25%). No AR expression was seen in 15 cases (63%) with GATA-3 positivity. There was no difference in either GATA-3 (4.3±2.7 vs. 3.6±2.5; p=0.549) or AR (1.4±2.5 vs. 1.1±2.4; p=0.778) expression between patients with and without pCR. CONCLUSIONS:GATA-3 expression is frequent in TNBC even in the absence of AR. However, neither GATA-3 nor AR are associated with pCR after neoadjuvant chemotherapy.
PMID: 27067807
ISSN: 1618-0631
CID: 5034122
A pilot trial to examine the association between circulating endothelial cell levels and vascular injury in patients with diabetes and chronic kidney disease
Shirazian, Shayan; Grant, Candace; Rambhujun, Vikash; Sharma, Ritika; Patel, Ronak; Islam, Shahidul; Mattana, Joseph
Objective While albuminuria is a marker for progressive chronic kidney disease (CKD) in patients with type 2 diabetes (T2DM), both albuminuric and normoalbuminuric patients appear prone to vascular injury. This pilot study examines the association between circulating endothelial cell (CEC) levels and vascular injury in patients with T2DM and CKD. Methods In this cross-sectional study, eligible adult patients had T2DM, and stage 3 CKD (estimated glomerular filtration rate between 30 and 60 mL/min/1.73m (2)). CEC levels were tested by Janssen Diagnostics, LLC using an immuno-magnetic bead-based assay. CEC levels were compared to levels in a previously tested normal population. Correlations between CEC levels and other vascular injury markers (urine albumin, von-Willebrand factor antigen, hs-CRP, uric acid) were performed. Results Patients included 40 adults of which nineteen were normoalbuminuric. Mean CEC levels (38.7, SD 38.1 cells) were significantly higher than the normal population (M = 21±18 cells, p<0.001; N = 249), including in the normoalbuminuric subgroup (M = 42.9±42.5 cells, p<0.001). CEC levels were significantly correlated with uric acid levels (r=0.33, p=0.039). Conclusions CEC levels in patients with T2DM and CKD, both albuminuric and normoalbuminuric, are significantly higher than a normal population, suggesting the presence of vascular injury in both groups. Future studies are needed to evaluate the role of CECs as a biomarker to predict outcomes in normoalbuminuric patients with CKD.
PMCID:4892336
PMID: 27303625
ISSN: 2046-1402
CID: 5034132
Biomarkers of Environmental Enteropathy are Positively Associated with Immune Responses to an Oral Cholera Vaccine in Bangladeshi Children
Uddin, Muhammad Ikhtear; Islam, Shahidul; Nishat, Naoshin S; Hossain, Motaher; Rafique, Tanzeem Ahmed; Rashu, Rasheduzzaman; Hoq, Mohammad Rubel; Zhang, Yue; Saha, Amit; Harris, Jason B; Calderwood, Stephen B; Bhuiyan, Taufiqur Rahman; Ryan, Edward T; Leung, Daniel T; Qadri, Firdausi
Environmental enteropathy (EE) is a poorly understood condition that refers to chronic alterations in intestinal permeability, absorption, and inflammation, which mainly affects young children in resource-limited settings. Recently, EE has been linked to suboptimal oral vaccine responses in children, although immunological mechanisms are poorly defined. The objective of this study was to determine host factors associated with immune responses to an oral cholera vaccine (OCV). We measured antibody and memory T cell immune responses to cholera antigens, micronutrient markers in blood, and EE markers in blood and stool from 40 Bangladeshi children aged 3-14 years who received two doses of OCV given 14 days apart. EE markers included stool myeloperoxidase (MPO) and alpha anti-trypsin (AAT), and plasma endotoxin core antibody (EndoCab), intestinal fatty acid binding protein (i-FABP), and soluble CD14 (sCD14). We used multiple linear regression analysis with LASSO regularization to identify host factors, including EE markers, micronutrient (nutritional) status, age, and HAZ score, predictive for each response of interest. We found stool MPO to be positively associated with IgG antibody responses to the B subunit of cholera toxin (P = 0.03) and IgA responses to LPS (P = 0.02); plasma sCD14 to be positively associated with LPS IgG responses (P = 0.07); plasma i-FABP to be positively associated with LPS IgG responses (P = 0.01) and with memory T cell responses specific to cholera toxin (P = 0.01); stool AAT to be negatively associated with IL-10 (regulatory) T cell responses specific to cholera toxin (P = 0.02), and plasma EndoCab to be negatively associated with cholera toxin-specific memory T cell responses (P = 0.02). In summary, in a cohort of children 3-14 years old, we demonstrated that the majority of biomarkers of environmental enteropathy were positively associated with immune responses after vaccination with an OCV.
PMCID:5100882
PMID: 27824883
ISSN: 1935-2735
CID: 5034172
1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag
Islam, Shahidul; Haque, Asadul; Bui, Ha Hong
Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS) cured up to 365 days. The void ratio-logarithm of pressure (e-logσ') behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis.
PMCID:5502982
PMID: 28773415
ISSN: 1996-1944
CID: 5034222
ANTI-OXIDATIVE, (α-GLUCOSIDASE AND α-AMYLASE INHIBITORY ACTIVITY OF VITEX DONIANA: POSSIBLE EXPLOITATION IN THE MANAGEMENT OF TYPE 2 DIABETES
Ibrahim, Mohammed Auwal; Koorbanally, Neil Anthony; Islam, Shahidul
Vitex doniana is an important African medicinal plant traditionally used for the treatment of many diseases including type 2 diabetes (T2D). In this study, ethyl acetate, ethanol and aqueous extracts of the stem bark, root and leaf of V. doniana were analyzed for in vitro anti-oxidative activity and the results indicated that the ethanolic extract of the leaves had the best anti-oxidative activity. Subsequently, the ethanolic extract of the leaves was partitioned between hexane, dichloromethane, ethyl acetate and water. The aqueous fraction had a significantly ( p < 0.05) higher phenolics content and also showed the best anti-oxidative activity within the fractions. Furthermore, the aqueous fraction demonstrated significantly (p < 0.05) more potent inhibitory activities against α-glucosidase and α-amylase than other fractions. Steady state kinetics analysis revealed that the aqueous fraction inhibited both (α-glucosidase and (α-amylase activities in a non-competitive manner with inhibition binding constant (Ki) values of 5.93 and 167.44 μg/mL, respectively. Analysis of the aqueous fraction by GC-MS showed the presence of resorcinol, 4-hydroxybenzoic acid, 3,4,5-trimethoxyphenol and 2,4'-dihydroxychalcone identified by their mass fragmentation patterns and comparison to standard spectra. The results obtained in this study showed that V doniana leaves have a good in vitro anti-T2D potential possibly elicited through phenolics.
PMID: 29638064
ISSN: 0001-6837
CID: 5034312
The Number of Recalled Leads is Highly Predictive of Lead Failure: Results From the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS")
Kersten, Daniel J; Yi, Jinju; Feldman, Alyssa M; Brahmbhatt, Kunal; Asheld, Wilbur J; Germano, Joseph; Islam, Shahidul; Cohen, Todd J
OBJECTIVES/OBJECTIVE:The purpose of this study was to determine if implantation of multiple recalled defibrillator leads is associated with an increased risk of lead failure. BACKGROUND:The authors of the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS") have previously reported a relationship between recalled lead status, lead failure, and patient mortality. This substudy analyzes the relationship in a smaller subset of patients who received more than one recalled lead. The specific effects of having one or more recalled leads have not been previously examined. METHODS:This study analyzed lead failure and mortality of 3802 patients in PAIDLESS and compared outcomes with respect to the number of recalled leads received. PAIDLESS includes all patients at Winthrop University Hospital who underwent defibrillator lead implantation between February 1, 1996 and December 31, 2011. Patients with no recalled ICD leads, one recalled ICD lead, and two recalled ICD leads were compared using the Kaplan-Meier method and log-rank test. Sidak adjustment method was used to correct for multiple comparisons. All calculations were performed using SAS 9.4. P-values <.05 were considered statistically significant. RESULTS:This study included 4078 total ICD leads implanted during the trial period. There were 2400 leads (59%) in the no recalled leads category, 1620 leads (40%) in the one recalled lead category, and 58 leads (1%) in the two recalled leads category. No patient received more than two recalled leads. Of the leads categorized in the two recalled leads group, 12 experienced lead failures (21%), which was significantly higher (P<.001) than in the no recalled leads group (60 failures, 2.5%) and one recalled lead group (81 failures; 5%). Multivariable Cox's regression analysis found a total of six significant predictive variables for lead failure including the number of recalled leads (P<.001 for one and two recalled leads group). CONCLUSIONS:The number of recalled leads is highly predictive of lead failure. Lead-based multivariable Cox's regression analysis produced a total of six predictive variable categories for lead failure, one of which was the number of recalled leads. Kaplan-Meier analysis showed that the leads in the two recalled leads category failed faster than both the no recalled lead and one recalled lead groups. The greater the number of recalled leads to which patients are exposed, the greater the risk of lead failure.
PMID: 27922811
ISSN: 1557-2501
CID: 3482342