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Gender-Related and Age-Related Differences in Implantable Defibrillator Recipients: Results From the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS")
Feldman, Alyssa M; Kersten, Daniel J; Chung, Jessica A; Asheld, Wilbur J; Germano, Joseph; Islam, Shahidul; Cohen, Todd J
OBJECTIVES/OBJECTIVE:The purpose of this study was to investigate the influences of gender and age on defibrillator lead failure and patient mortality. BACKGROUND:The specific influences of gender and age on defibrillator lead failure have not previously been investigated. METHODS:This study analyzed the differences in gender and age in relation to defibrillator lead failure and mortality of patients in the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS"). PAIDLESS includes all patients at Winthrop University Hospital who underwent defibrillator lead implantation between February 1, 1996 and December 31, 2011. Male and female patients were compared within each age decile, beginning at 15 years old, to analyze lead failure and patient mortality. Statistical analyses were performed using Wilcoxon rank-sum test, Fisher's exact test, Kaplan-Meier analysis, and multivariable Cox regression models. P<.05 was considered statistically significant. No correction for multiple comparisons was performed for the subgroup analyses. RESULTS:A total of 3802 patients (2812 men and 990 women) were included in the analysis. The mean age was 70 ± 13 years (range, 15-94 years). Kaplan-Meier analysis found that between 45 and 54 years of age, leads implanted in women failed significantly faster than in men (P=.03). Multivariable Cox regression models were built to validate this finding, and they confirmed that male gender was an independent protective factor of lead failure in the 45 to 54 years group (for male gender: HR, 0.37; 95% confidence interval, 0.14-0.96; P=.04). Lead survival time for women in this age group was 13.4 years (standard error, 0.6), while leads implanted in men of this age group survived 14.7 years (standard error, 0.3). Although there were significant differences in lead failure, no differences in mortality between the genders were found for any ages or within each decile. CONCLUSIONS:This study is the first to compare defibrillator lead failure and patient mortality in relation to gender and age deciles at a single large implanting center. Within the 45 to 54 years group, leads implanted in women failed faster than in men. Male gender was found to be an independent protective factor in lead survival. This study emphasizes the complex interplay between gender and age with respect to implantable defibrillator lead failure and mortality.
PMID: 26630641
ISSN: 1557-2501
CID: 3482332
Antioxidant, antidiabetic and hypolipidemic effects of Tulbaghia violacea Harv. (wild garlic) rhizome methanolic extract in a diabetic rat model
Moodley, Kogi; Joseph, Kimane; Naidoo, Yougasphree; Islam, Shahidul; Mackraj, Irene
BACKGROUND:The prevalence of diabetes mellitus (DM) continues to rise alarmingly despite years of intensive research. The need to explore alternative remedies such as traditional phytotherapy has therefore become increasingly important in the management and treatment of DM. METHODS:Diabetes was induced by a single intraperitoneal (i.p) injection of streptozotocin (40 mg/kg.b.w) in male Wistar rats. The rats were divided into 5 groups as follows: non-diabetic control fed distilled water, diabetic control fed distilled water, diabetic group treated with Tulbaghia violacea (TVL) (60 mg/kg.b.w), diabetic group treated with TVL (120 mg/kg.b.w), and diabetic group treated with glibenclamide (10 mg/kg.b.w). Food and water intake, as well as urine output were measured daily, whilst body weight and fasting blood glucose were monitored weekly. On day 42, an oral glucose tolerance test was performed on all groups. After 7 weeks, the animals were sacrificed by halothane overdose, blood was removed by cardiac puncture and tissues were harvested. Assays were performed for the determination of plasma insulin, liver glycogen content, lipid peroxidation, antioxidant enzyme levels, plasma nitric oxide levels and serum lipid and liver enzyme levels. RESULTS AND DISCUSSION/CONCLUSIONS:TVL treatment improved body weights, significantly reduced fasting blood glucose levels, improved glucose tolerance and significantly increased plasma insulin and liver glycogen content. TVL treatment also reduced liver thiobarbituric acid reactive substances (TBARS) levels, increased liver superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) and increased plasma nitric oxide (NO) levels. Furthermore, TVL administration reduced serum triglycerides, VLDL, total-cholesterol levels and increased HDL-cholesterol levels. TVL also reduced serum levels of liver enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST). CONCLUSION/CONCLUSIONS:Data obtained in this study demonstrated the hypoglycemic, antioxidant, hepatoprotective and hypolipidemic effects of TVL in STZ-induced diabetic rats.
PMCID:4647322
PMID: 26577219
ISSN: 1472-6882
CID: 5034072
Free 25(OH)D and the Vitamin D Paradox in African Americans
Aloia, John; Mikhail, Mageda; Dhaliwal, Ruban; Shieh, Albert; Usera, Gianina; Stolberg, Alexandra; Ragolia, Louis; Islam, Shahidul
CONTEXT: African Americans have a lower total serum 25-hydroxyvitamin D [25(OH)D] but superior bone health. This has been referred to as a paradox. A recent publication found that free serum 25(OH)D is the same in black and white individuals. However, the study was criticized because an indirect method was used to measure free 25(OH)D. A direct method has recently been developed. OBJECTIVE: We hypothesized that although total serum 25(OH)D is lower in African Americans, free serum 25(OH)D measured directly would not differ between races. DESIGN: White and black healthy postmenopausal women were matched for age and body mass index. Serum total 25(OH)D, PTH, 1,25-dihydroxyvitamin D, vitamin D binding protein (VDBP), and bone density were measured. Measurement of free 25(OH)D was carried out using an ELISA. SETTING: The study was conducted at an ambulatory research unit in a teaching hospital. OUTCOME: A cross-racial comparison of serum free 25(OH)D was performed. RESULTS: A propensity match resulted in the selection of a total of 164 women. Total 25(OH)D was lower in black women (19.5 +/- 4.7 vs 26.9 +/- 6.4 ng/mL), but a direct measurement of free 25(OH)D revealed almost identical values (5.25 +/- 1.2 vs 5.25 +/- 1.3 ng/mL) between races. VDBP was significantly lower in blacks when using a monoclonal-based ELISA but higher with a polyclonal-based ELISA. Serum PTH, 1,25-dihydroxyvitamin D, and bone density were higher in African Americans. CONCLUSIONS: Free serum 25(OH)D is the same across races despite the lower total serum 25(OH)D in black women. Results comparing VDBP between races using a monoclonal vs a polyclonal assay were discordant.
PMCID:4570168
PMID: 26161453
ISSN: 1945-7197
CID: 2598942
Urinary calcium excretion in postmenopausal African American women
Aloia, John F; Shieh, Albert; Mikhail, Mageda; Islam, Shahidul
AIM: The objective of this study was to develop a reference range for urine calcium excretion (both 24-hour and fasting) for African American women compared to White women. In addition, the variables that determine urine calcium excretion were identified. MATERIAL: Data were analyzed for baseline studies of healthy postmenopausal volunteers who participated in seven separate studies conducted at one site. METHODS: Some studies included fasting urine Ca/Cr and others 24-hour urine calcium excretion. 24-hour urine calcium was considered with and without correction for urinary creatinine excretion. Calcium was measured initially by atomic absorption spectrophotometry and more recently by an automated method (ADVIA 2400 Chemistry System). RESULTS: Participants were considered healthy based on history and physical and routine laboratory studies. Those screened who had a history of nephrolithiasis were excluded. A reference range for 24-hour urine calcium and fasting urine calcium/ creatinine was developed. Reference intervals of 11 - 197 mg/24-hour urine calcium excretion and of 0.007 - 0.222 of fasting Ca/Cr were found for African American women compared to 21 - 221 mg/24 hours and 0.019 - 0.264 in White women, respectively. Urine creatinine excretion was higher in African Americans consistent with their higher muscle mass. CONCLUSION: Urine calcium excretion is lower in postmenopausal African American than White women. The reference range developed should be considered in the diagnosis of hypocalciuric states and may also be useful in the diagnosis of hypercalciuria.
PMCID:4928031
PMID: 26226948
ISSN: 0301-0430
CID: 2598932
A Comparative Study of Defibrillator Leads at a Large-Volume Implanting Hospital: Results From the Pacemaker and Implantable Defibrillator Leads Survival Study ("PAIDLESS")
Cohen, Todd J; Asheld, Wilbur J; Germano, Joseph; Islam, Shahidul; Patel, Dhimesh
OBJECTIVES/OBJECTIVE:The purpose of the study was to examine survival in the implantable defibrillator subset of implanted leads at a large-volume implanting hospital. BACKGROUND:Implantable lead survival has been the subject of many multicenter studies over the past decade. Fewer large implanting volume single-hospital studies have examined defibrillator lead failure as it relates to patient survival and lead construction. METHODS:This investigator-initiated retrospective study examined defibrillator lead failure in those who underwent implantation of a defibrillator between February 1, 1996 and December 31, 2011. Lead failure was defined as: failure to capture/sense, abnormal pacing and/or defibrillator impedance, visual insulation defect or lead fracture, extracardiac stimulation, cardiac perforation, tricuspid valve entrapment, lead tip fracture and/or lead dislodgment. Patient characteristics, implant approach, lead manufacturers, lead models, recalled status, patient mortality, and core lead design elements were compared using methods that include Kaplan Meier analysis, univariate and multivariable Cox regression models. RESULTS:A total of 4078 defibrillator leads were implanted in 3802 patients (74% male; n = 2812) with a mean age of 70 ± 13 years at Winthrop University Hospital. Lead manufacturers included: Medtronic: [n = 1834; 801 recalled]; St. Jude Medical: [n = 1707; 703 recalled]; Boston Scientific: [n = 537; 0 recalled]. Kaplan-Meier analysis adjusted for multiple comparisons revealed that both Boston Scientific's and St. Jude Medical's leads had better survival than Medtronic's leads (P<.001 and P=.01, respectively). Lead survival was comparable between Boston Scientific and St. Jude Medical (P=.80). A total of 153 leads failed (3.5% of all leads) during the study. There were 99 lead failures from Medtronic (5.4% failure rate); 56 were recalled Sprint Fidelis leads. There were 36 lead failures from St. Jude (2.1% failure rate); 20 were recalled Riata or Riata ST leads. There were 18 lead failures from Boston Scientific (3.35% failure rate); none were recalled. Kaplan Meier analysis also showed lead failure occurred sooner in the recalled leads (P=.01). A total of 1493 patients died during the study (mechanism of death was largely unknown). There was a significant increase in mortality in the recalled lead group as compared with non-recalled leads (P=.01), but no significant difference in survival when comparing recalled leads from Medtronic with St. Jude Medical (P=.67). A multivariable Cox regression model revealed younger age, history of percutaneous coronary intervention, baseline rhythm other than atrial fibrillation or atrial flutter, combination polyurethane and silicone lead insulation, a second defibrillation coil, and recalled lead status all contributed to lead failure. CONCLUSION/CONCLUSIONS:This study demonstrated a significantly improved lead performance in the Boston Scientific and St. Jude leads as compared with Medtronic leads. Some lead construction variables (insulation and number of coils) also had a significant impact on lead failure, which was independent of the manufacturer. Recalled St. Jude leads performed better than recalled Medtronic leads in our study. Recalled St. Jude leads had no significant difference in lead failure when compared with the other manufacturer's non-recalled leads. Defibrillator recalled lead status was associated with an increased mortality as compared with non-recalled leads. This correlation was independent of the lead manufacturer and clinically significant even when considering known mortality risk factors. These results must be tempered by the largely unknown mechanism of death in these patients.
PMID: 26028656
ISSN: 1557-2501
CID: 3482322
Impact of computerized physician order entry alerts on prescribing in older patients
Lester, Paula E; Rios-Rojas, Liliana; Islam, Shahidul; Fazzari, Melissa J; Gomolin, Irving H
BACKGROUND:A computerized physician order entry (CPOE) system provides opportunity for real-time alerts to prescribers. Winthrop University Hospital began using CPOE in 2009. OBJECTIVE:We sought to improve prescribing among older hospitalized patients by adding alerts to the CPOE system for potentially inappropriate medications. METHODS:In January 2011, informational alerts were integrated into the CPOE system for selected high-risk medications: diphenhydramine, metoclopramide, and all antipsychotics. We evaluated the effect of these alerts on prescribing frequency by comparing the number of prescriptions during the second quarters of 2010 ("pre-alert") with the second quarters of 2011 through 2013 ("post-alert"). Prescribing patterns were evaluated through a pharmacy database of medication orders. Frequency of prescribing was adjusted for total discharges. A comparison was made to ages 18-64 years, and comparing "as needed" vs standing orders. RESULTS:In the 65 years of age and older group, there were significant reductions in prescription rates pre-alert vs post-alert for diphenhydramine (p < 0.001) and metoclopramide (p < 0.001). There was no decrease in prescription rates for antipsychotics in older patients (p = 0.80). In the younger comparison group, no decreases in prescription rates for those drugs were observed. Our analysis is based on numbers of written prescriptions and not actual doses administered; therefore, no conclusions concerning the effect of these alerts on communication or documentation of risk/benefits of these medications can be ascertained. CONCLUSION/CONCLUSIONS:The data suggest that prescribing rates for drugs with the least efficacy and potential for harm and with alternative agents (i.e., diphenhydramine and metoclopramide) can be modified by CPOE alerts for older patients.
PMID: 25752906
ISSN: 1179-1969
CID: 3466342
Protein arginine methyltransferase 7 promotes breast cancer cell invasion through the induction of MMP9 expression
Baldwin, R Mitchell; Haghandish, Nasim; Daneshmand, Manijeh; Amin, Shahrier; Paris, Geneviève; Falls, Theresa J; Bell, John C; Islam, Shahidul; Côté, Jocelyn
Recent evidence points to the protein arginine methyltransferase (PRMT) family of enzymes playing critical roles in cancer. PRMT7 has been identified in several gene expression studies to be associated with increased metastasis and decreased survival in breast cancer patients. However, this has not been extensively studied. Here we report that PRMT7 expression is significantly upregulated in both primary breast tumour tissues and in breast cancer lymph node metastases. We have demonstrated that reducing PRMT7 levels in invasive breast cancer cells using RNA interference significantly decreased cell invasion in vitro and metastasis in vivo. Conversely, overexpression of PRMT7 in non-aggressive MCF7 cells enhanced their invasiveness. Furthermore, we show that PRMT7 induces the expression of matrix metalloproteinase 9 (MMP9), a well-known mediator of breast cancer metastasis. Importantly, we significantly rescued invasion of aggressive breast cancer cells depleted of PRMT7 by the exogenous expression of MMP9. Our results demonstrate that upregulation of PRMT7 in breast cancer may have a significant role in promoting cell invasion through the regulation of MMP9. This identifies PRMT7 as a novel and potentially significant biomarker and therapeutic target for breast cancer.
PMCID:4413634
PMID: 25605249
ISSN: 1949-2553
CID: 5034012
An historic step for advanced cytopathology training in Canada
Auger, Manon; Islam, Shahidul; Weir, Michele
PMID: 25251992
ISSN: 1934-6638
CID: 5033962
Identification of Low Molecular Weight Glutenin Alleles by Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-MS) in Common Wheat (Triticum aestivum L.)
Wang, Aili; Liu, Li; Peng, Yanchun; Islam, Shahidul; Applebee, Marie; Appels, Rudi; Yan, Yueming; Ma, Wujun
Low molecular weight glutenin subunits (LMW-GS) play an important role in determining dough properties and breadmaking quality. However, resolution of the currently used methodologies for analyzing LMW-GS is rather low which prevents an efficient use of genetic variations associated with these alleles in wheat breeding. The aim of the current study is to evaluate and develop a rapid, simple, and accurate method to differentiate LMW-GS alleles using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. A set of standard single LMW-GS allele lines as well as a suite of well documented wheat cultivars were collected from France, CIMMYT, and Canada. Method development and optimization were focused on protein extraction procedures and MALDI-TOF instrument settings to generate reproducible diagnostic spectrum peak profiles for each of the known wheat LMW-GS allele. Results revealed a total of 48 unique allele combinations among the studied genotypes. Characteristic MALDI-TOF peak patterns were obtained for 17 common LMW-GS alleles, including 5 (b, a or c, d, e, f), 7 (a, b, c, d or i, f, g, h) and 5 (a, b, c, d, f) patterns or alleles for the Glu-A3, Glu-B3, and Glu-D3 loci, respectively. In addition, some reproducible MALDI-TOF peak patterns were also obtained that did not match with any known alleles. The results demonstrated a high resolution and throughput nature of MALDI-TOF technology in analyzing LMW-GS alleles, which is suitable for application in wheat breeding programs in processing a large number of wheat lines with high accuracy in limited time. It also suggested that the variation of LMW-GS alleles is more abundant than what has been defined by the current nomenclature system that is mainly based on SDS-PAGE system. The MALDI-TOF technology is useful to differentiate these variations. An international joint effort may be needed to assign allele symbols to these newly identified alleles and determine their effects on end-product quality attributes.
PMCID:4583301
PMID: 26407296
ISSN: 1932-6203
CID: 5034042
Two Novel Y-Type High Molecular Weight Glutenin Genes in Chinese Wheat Landraces of the Yangtze-River Region
Peng, Yanchun; Yu, Kan; Zhang, Yujuan; Islam, Shahidul; Sun, Dongfa; Ma, Wujun
High molecular weight glutenin subunits (HMW-GSs) are key determinants for the end-use quality of wheat. Chinese wheat landraces are an important resource for exploring novel HMW-GS genes to improve the wheat baking quality. Two novel Glu-1Dy HMW-GSs (designated as 1Dy12.6 and 1Dy12.7) were identified and cloned from two Chinese wheat landraces Huazhong830 and Luosimai. The 1Dy12.6 and 1Dy12.7 subunits were deposited as the NCBInr Acc. No KR262518, and KR262519, respectively. The full open reading frames (ORFs) of 1Dy12.6 and 1Dy12.7 were 2022 bp and 1977 bp, encoding for proteins of 673 and 658 amino acid residues, respectively. Each contains four typical primary regions of HMW-GSs (a signal peptide, N- and C-terminal regions, and a central repetitive region). Their deduced molecular masses (70,165 Da and 68,400 Da) were strikingly consistent with those identified by MALDI-TOF-MS (69,985Da and 68,407 Da). The 1Dy12.6 is the largest 1Dy glutenin subunits cloned in common wheat up to date, containing longer repetitive central domains than other 1Dy encoded proteins. In comparison with the most similar active 1Dy alleles previously reported, the newly discovered alleles contained a total of 20 SNPs and 3 indels. The secondary structure prediction indicated that 1Dy12.6 and 1Dy12.7 have similar proportion of α-helix, β-turn, and β-bend to those of 1Dy10 (X12929). The phylogenetic analysis illustrated that the x- and y-type subunits of glutenins were well separated, but both 1Dy12.6 and 1Dy12.7 were clustered with the other Glu-1Dy alleles. Our results revealed that the 1Dy12.6 and 1Dy12.7 subunit have potential to strengthen gluten polymer interactions, and are valuable genetic resources for wheat quality improvement.
PMCID:4635010
PMID: 26540300
ISSN: 1932-6203
CID: 5034062