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Echlin H.,Alabama | Echlin H.,University of Alabama at Birmingham | Zhu F.,Alabama | Zhu F.,University of Alabama at Birmingham | And 9 more authors.
Journal of Bacteriology | Year: 2013

Serine-rich repeat glycoproteins (SRRPs) are important bacterial adhesins conserved in streptococci and staphylococci. Fap1, a SRRP identified in Streptococcus parasanguinis, is the major constituent of bacterial fimbriae and is required for adhesion and biofilm formation. An 11-gene cluster is required for Fap1 glycosylation and secretion; however, the exact mechanism of Fap1 biogenesis remains a mystery. Two glycosylation-associated proteins within this cluster-Gap1 and Gap3-function together in Fap1 biogenesis. Here we report the role of the third glycosylation-associated protein, Gap2. A gap2 mutant exhibited the same phenotype as the gap1 and gap3 mutants in terms of Fap1 biogenesis, fimbrial assembly, and bacterial adhesion, suggesting that the three proteins interact. Indeed, all three proteins interacted with each other independently and together to form a stable protein complex. Mechanistically, Gap2 protected Gap3 from degradation by ClpP protease, and Gap2 required the presence of Gap1 for expression at the wild-type level. Gap2 augmented the function of Gap1 in stabilizing Gap3; this function was conserved in Gap homologs from Streptococcus agalactiae. Our studies demonstrate that the three Gap proteins work in concert in Fap1 biogenesis and reveal a new function of Gap2. This insight will help us elucidate the molecular mechanism of SRRP biogenesis in this bacterium and in pathogenic species. © 2013, American Society for Microbiology.


Yancey D.M.,University of Alabama at Birmingham | Guichard J.L.,University of Alabama at Birmingham | Ahmed M.I.,University of Alabama at Birmingham | Zhou L.,University of Alabama at Birmingham | And 6 more authors.
American journal of physiology. Heart and circulatory physiology | Year: 2015

Left ventricular (LV) volume overload (VO) results in cardiomyocyte oxidative stress and mitochondrial dysfunction. Because mitochondria are both a source and target of ROS, we hypothesized that the mitochondrially targeted antioxidant mitoubiquinone (MitoQ) will improve cardiomyocyte damage and LV dysfunction in VO. Isolated cardiomyocytes from Sprague-Dawley rats were exposed to stretch in vitro and VO of aortocaval fistula (ACF) in vivo. ACF rats were treated with and without MitoQ. Isolated cardiomyocytes were analyzed after 3 h of cyclical stretch or 8 wk of ACF with MitoSox red or 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate to measure ROS and with tetramethylrhodamine to measure mitochondrial membrane potential. Transmission electron microscopy and immunohistochemistry were used for cardiomyocyte structural assessment. In vitro cyclical stretch and 8-wk ACF resulted in increased cardiomyocyte mitochondrial ROS production and decreased mitochondrial membrane potential, which were significantly improved by MitoQ. ACF had extensive loss of desmin and β₂-tubulin that was paralleled by mitochondrial disorganization, loss of cristae, swelling, and clustering identified by mitochondria complex IV staining and transmission electron microscopy. MitoQ improved mitochondrial structural damage and attenuated desmin loss/degradation evidenced by immunohistochemistry and protein expression. However, LV dilatation and fractional shortening were unaffected by MitoQ treatment in 8-wk ACF. In conclusion, although MitoQ did not affect LV dilatation or function in ACF, these experiments suggest a connection of cardiomyocyte mitochondria-derived ROS production with cytoskeletal disruption and mitochondrial damage in the VO of ACF.


Subramaniam A.,University of Alabama at Birmingham | Tang Y.,Alabama | Biggio J.R.,Alabama | Edwards R.K.,Alabama | Robin N.H.,University of Alabama at Birmingham
American Journal of Medical Genetics, Part A | Year: 2016

We conducted a survey-based study of the opinions, attitudes, and management practices of neonatologists across the United States regarding prenatally diagnosed Trisomy 18. The survey was designed based on previously validated surveys of severe fetal anomalies and collected demographic information on participants, as well as their attitudes, and management choices given a series of vignettes beginning in the prenatal period. The survey was sent to 3,143 American Academy of Pediatrics Section on Neonatal-Perinatal Medicine members of which 409 (13%) completed the survey. While the response rate was rather low, our respondent pool was representative of the national neonatologist population. Respondents were predominately white (81%), married (88%), Christian (54%), had children (86%), and were pro-choice in terms of abortion (68%). Eighty-three percent (83%) of respondents thought that trisomy 18 is a lethal condition and 60% thought that treatment is futile. Seventy-five percent (75%) expected that the best neurodevelopmental outcome in the case of infant survival would be profound intellectual disability. Regarding neonatal care, 95% stated that they would recommend palliative care only. Ninety-five percent (95%) would never recommend or recommend only if asked full code resuscitation for a neonate with full trisomy 18, yet, 44% would comply partially or in full with a full code request for resuscitation measures. The demographic features that correlated most significantly with these responses were clinician race and years in practice. The attitudes toward and management of infants affected with trisomy 18 seem to be largely driven by parental attitudes and wishes. © 2016 Wiley Periodicals, Inc.


PubMed | Alabama., Atlanta Veterans Affairs Medical Center, University of Alabama at Birmingham, Emory University and Birmingham Atlanta GRECC
Type: | Journal: Clinical therapeutics | Year: 2016

Nocturia and sleep problems are common in older adults. We developed and tested a novel intervention, multicomponent behavioral treatment and exercise therapy (M-BET), that may reduce nocturia and improve sleep in men. We compared reductions in nocturia and improvement in sleep in men with M-BET versus an active drug comparator (-blocker) used alone or in combination (M-BET + -blocker) METHODS: This randomized, controlled trial was conducted in the ambulatory setting in 2 US Department of Veterans Affairs medical centers in men at least 40 years of age with nocturia (defined as 2 nightly episodes). Participants were randomized to receive either M-BET, including pelvic floor muscle training, urge-suppression techniques, delayed voiding, fluid management, sleep hygiene, and peripheral edema management; an active comparator of known efficacy (the -blocker tamsulosin, one 0.4-mg tablet nightly); or both therapies combined. Participants received interventions over 12 weeks. Outcomes were assessed via voiding diaries, wrist actigraphy, and validated questionnaires. The primary outcome was change in diary-recorded nocturia, assessed using ANCOVA for the between-group changes and paired t tests for within-group changes.A total of 72 men with a mean age of 65.8 years participated. At 12 weeks, mean diary-recorded nocturia changed with M-BET by -1.39 episodes/night (P < 0.001), with -blocker therapy by -0.59 episodes/night (P < 0.01), and with combination therapy by -1.03 episodes/night (P < 0.01). Reductions were not statistically different across treatment groups (P = 0.41). M-BET also showed statistically significant improvements in sleep quality, bother from nocturia, and nocturia-specific quality of life. All treatment groups indicated global satisfaction with treatment.Behavioral therapy in men, alone or combined with -blocker therapy, consistently showed large and statistically significant nocturia reductions and favorable effects on sleep and quality of life. Based on these findings, behavioral therapy, while not statistically superior to -blocker therapy, may provide a meaningful treatment option for men with nocturia. Future research should include the development of behavioral treatment and exercise therapy interventions that could be more easily deployed. ClinicalTrials.gov identifier: NCT00824200.


PubMed | Alabama.
Type: Journal Article | Journal: Gastroenterology & hepatology | Year: 2016

Hepatocellular carcinoma (HCC) is an important cause of cancer-related death worldwide. If the disease is detected early, the treatment is more likely to be curative. This article discusses the current evidence regarding the surveillance and diagnosis of HCC, focusing on recent articles and the recommendations of the American Association for the Study of Liver Diseases (AASLD), which are briefly compared with the recommendations of other liver disease organizations. HCC surveillance aims to detect disease at an early stage in order to augment the likelihood of curative treatment. According to AASLD recommendations, patients who have cirrhosis and those who do not have cirrhosis but are at high risk for HCC should be screened. Ultrasonogra-phy (USG) at 6-month intervals is recommended. The available serologic markers, including serum alpha-fetoprotein, are inadequate for surveillance, even when combined with USG. Despite achievements in HCC management, physicians continue to underutilize surveillance. Quadruple-phase, contrast-enhanced computed tomography scans or magnetic resonance images with characteristic radiologic findings are commonly used to diagnose HCC in suspicious cases. The available surveillance and diagnostic tests effectively identify HCC at an early stage, and as a result, the chances of cure are increased. Physicians caring for patients who have cirrhosis and chronic liver disease should be familiar with HCC surveillance recommendations and the prognostic importance of early diagnosis.


PubMed | Alabama., HCI Inc and University of Alabama at Birmingham
Type: Journal Article | Journal: Biotechnic & histochemistry : official publication of the Biological Stain Commission | Year: 2016

The variable quality of histochemical and immunohistochemical staining of tissues may be attributed to pre-analytical and analytical variables. Both categories of variables frequently are undefined or inadequately controlled during specimen collection and preparation. Pre-analytical variables may alter the molecular composition of tissues, which results in variable staining; such variations may cause problems when different tissues are used as staining controls. We developed a standard tissue for use as a staining control. Our standard tissue contains five components: 1) nine combined human cell lines mixed with stroma from human spleen; 2) a squamous cancer cell line, A431; 3) fungus; 4) transverse sections of the mosquitofish and 5) normal human spleen. The first three components were embedded in HistoGel() and all components were processed to paraffin and used to construct a single standard paraffin block. The muscles of mosquitofish and arteries of the spleen are positive controls for eosin staining, while other tissues are useful for assessing hematoxylin staining. The mosquitofish tissues also are excellent controls for the Masson trichrome stain and all mucin-related histochemical stains that we tested. The goblet cells of the intestine and skin stained strongly with Alcian blue, pH 2.5 (AB-2.5), mucicarmine, colloidal iron, periodic acid Schiff (PAS) or PAS-hematoxylin (PASH) and combination stains such as colloidal iron-PASH. Cell lines were not useful for evaluating histochemical stains except for PASH. The splenic stroma was a useful control for AB-2.5; however, eosin and mucin stains stained cell lines poorly, probably due to their rapid growth and associated loss of some differentiated characteristics such as production of mucins. Nevertheless, the cell lines were a critical control for immunohistochemical stains. Immunostaining of specific cell lines was consistent with the presence of markers, e.g., EGFr in DU145 cells. The cell lines expressed a wide range of markers, so they were useful controls for immunohistochemical staining including EGFr, HER2, E-cadherin, cytokeratins, Ki67, PCNA, estrogen receptor, progesterone receptor, CD3, CD20 and CD45, activated (cleaved) caspase 3 and Bcl-2. The cell lines also were a control for the TUNEL stain.


PubMed | Alabama., Alabama, National University of Singapore, Washington State University and University of Alabama at Birmingham
Type: Journal Article | Journal: American journal of physiology. Heart and circulatory physiology | Year: 2014

High-fat, low-carbohydrate diets (HFLCD) are often eaten by humans for a variety of reasons, but the effects of such diets on the heart are incompletely understood. We evaluated the impact of HFLCD on myocardial ischemia/reperfusion (I/R) using an in vivo model of left anterior descending coronary artery ligation. Sprague-Dawley rats (300 g) were fed HFLCD (60% calories fat, 30% protein, 10% carbohydrate) or control (CONT; 16% fat, 19% protein, 65% carbohydrate) diet for 2 wk and then underwent open chest I/R. At baseline (preischemia), diet did not affect left ventricular (LV) systolic and diastolic function. Oil red O staining revealed presence of lipid in the heart with HFLCD but not in CONT. Following I/R, recovery of LV function was decreased in HFLCD. HFLCD hearts exhibited decreased ATP synthase and increased uncoupling protein-3 gene and protein expression. HFLCD downregulated mitochondrial fusion proteins and upregulated fission proteins and store-operated Ca(2+) channel proteins. HFLCD led to increased death during I/R; 6 of 22 CONT rats and 16 of 26 HFLCD rats died due to ventricular arrhythmias and hemodynamic shock. In surviving rats, HFLCD led to larger infarct size. We concluded that in vivo HFLCD does not affect nonischemic LV function but leads to greater myocardial injury during I/R, with increased risk of death by pump failure and ventricular arrhythmias, which might be associated with altered cardiac energetics, mitochondrial fission/fusion dynamics, and store-operated Ca(2+) channel expression.


PubMed | University of Michigan, University of Pennsylvania, Alabama., Vanderbilt Heart and Vascular Institute and 9 more.
Type: Journal Article | Journal: The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation | Year: 2016

The prognosis of ambulatory patients with advanced heart failure (HF) who are not yet inotrope dependent and implications for evaluation and timing for transplant or destination therapy with a left ventricular assist device (DT-LVAD) are unknown. We hypothesized that the characteristics defining eligibility for advanced HF therapies would be a primary determinant of outcomes in these patients.Ambulatory patients with advanced HF (New York Heart Association class III-IV, Interagency Registry for Mechanically Assisted Circulatory Support profiles 4-7) were enrolled across 11 centers from May 2013 to February 2015. Patients were stratified into 3 groups: likely transplant eligible, DT-LVAD eligible, and ineligible for both transplant and DT-LVAD. Clinical characteristics were collected, and patients were prospectively followed for death, transplant, and left ventricular assist device implantation.The study enrolled 144 patients with a mean follow-up of 10 6 months. Patients in the ineligible cohort (n = 43) had worse congestion, renal function, and anemia compared with transplant (n = 51) and DT-LVAD (n = 50) eligible patients. Ineligible patients had higher mortality (23.3% vs 8.0% in DT-LVAD group and 5.9% in transplant group, p = 0.02). The differences in mortality were related to lower rates of transplantation (11.8% in transplant group vs 2.0% in DT-LVAD group and 0% in ineligible group, p = 0.02) and left ventricular assist device implantation (15.7% in transplant group vs 2.0% in DT-LVAD group and 0% in ineligible group, p < 0.01).Ambulatory patients with advanced HF who were deemed ineligible for transplant and DT-LVAD had markers of greater HF severity and a higher rate of mortality compared with patients eligible for transplant or DT-LVAD. The high early event rate in this group emphasizes the need for timely evaluation and decision making regarding lifesaving therapies.


PubMed | Alabama. and University of Washington
Type: | Journal: Pediatric pulmonology | Year: 2015

Cystic Fibrosis is caused by mutations in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene resulting in abnormal protein function. Recent advances of targeted molecular therapies and high throughput screening have resulted in multiple drug therapies that target many important mutations in the CFTR protein. In this review, we provide the latest results and current progress of CFTR modulators for the treatment of cystic fibrosis, focusing on potentiators of CFTR channel gating and Phe508del processing correctors for the Phe508del CFTR mutation. Special emphasis is placed on the molecular basis underlying these new therapies and emerging results from the latest clinical trials. The future directions for augmenting the rescue of Phe508del with CFTR modulators are also emphasized.


PubMed | Alabama. and University of Alabama at Birmingham
Type: Journal Article | Journal: American journal of medical genetics. Part A | Year: 2016

We conducted a survey-based study of the opinions, attitudes, and management practices of neonatologists across the United States regarding prenatally diagnosed Trisomy 18. The survey was designed based on previously validated surveys of severe fetal anomalies and collected demographic information on participants, as well as their attitudes, and management choices given a series of vignettes beginning in the prenatal period. The survey was sent to 3,143 American Academy of Pediatrics Section on Neonatal-Perinatal Medicine members of which 409 (13%) completed the survey. While the response rate was rather low, our respondent pool was representative of the national neonatologist population. Respondents were predominately white (81%), married (88%), Christian (54%), had children (86%), and were pro-choice in terms of abortion (68%). Eighty-three percent (83%) of respondents thought that trisomy 18 is a lethal condition and 60% thought that treatment is futile. Seventy-five percent (75%) expected that the best neurodevelopmental outcome in the case of infant survival would be profound intellectual disability. Regarding neonatal care, 95% stated that they would recommend palliative care only. Ninety-five percent (95%) would never recommend or recommend only if asked full code resuscitation for a neonate with full trisomy 18, yet, 44% would comply partially or in full with a full code request for resuscitation measures. The demographic features that correlated most significantly with these responses were clinician race and years in practice. The attitudes toward and management of infants affected with trisomy 18 seem to be largely driven by parental attitudes and wishes. 2016 Wiley Periodicals, Inc.

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