Regulation of Hemolysin Expression and Virulence of Staphylococcus aureus by a Serine/Threonine Kinase and Phosphatase

Exotoxins, including the hemolysins known as the alpha (α) and beta (β) toxins, play an important role in the pathogenesis of Staphylococcus aureus infections. A random transposon library was screened for S. aureus mutants exhibiting altered hemolysin expression compared to wild type. Transposon insertions in 72 genes resulting in increased or decreased hemolysin expression were identified. Mutations inactivating a putative cyclic di-GMP synthetase and a serine/threonine phosphatase (Stp1) were found to reduce hemolysin expression, and mutations in genes encoding a two component regulator PhoR, LysR family transcriptional regulator, purine biosynthetic enzymes and a serine/threonine kinase (Stk1) increased expression. Transcription of the hla gene encoding α toxin was decreased in a Δstp1 mutant strain and increased in a Δstk1 strain. Microarray analysis of a Δstk1 mutant revealed increased transcription of additional exotoxins. A Δstp1 strain is severely attenuated for virulence in mice and elicits less inflammation and IL-6 production than the Δstk1 strain. In vivo phosphopeptide enrichment and mass spectrometric analysis revealed that threonine phosphorylated peptides corresponding to Stk1, DNA binding histone like protein (HU), serine-aspartate rich fibrinogen/bone sialoprotein binding protein (SdrE) and a hypothetical protein (NWMN_1123) were present in the wild type and not in the Δstk1 mutant. Collectively, these studies suggest that Stk1 mediated phosphorylation of HU, SrdE and NWMN_1123 affects S. aureus gene expression and virulence

Implementation of low glycemic index diet together with cornstarch in post-gastric bypass hypoglycemia: Two case reports

Post-bariatric hypoglycemia (PBH) is an increasingly recognized long-term complication of bariatric surgery. The nutritional treatment of PBH includes a high-fiber diet and the restriction of soluble and high-glycemic index carbohydrates; however, these measures are not always enough to prevent hypoglycemia. We evaluated the efficacy of uncooked cornstarch, a low-glycemic index carbohydrate characterized by slow intestinal degradation and absorption, in addition to a high-fiber diet, for the treatment of PBH. We report the cases of two young women suffering from severe postprandial and fasting hypoglycemia following Roux-en-Y gastric bypass (RYGB). The patients underwent Continuous Glucose Monitoring (CGM) before and 12⁻16 weeks after the administration of uncooked cornstarch (respectively 1.25 g/kg b.w. and 1.8 g/kg b.w.) in addition to a high-fiber diet. In both patients, CGM showed more stable glucose levels throughout monitoring, a remarkable reduction of the time spent in hypoglycemia

Differential Contribution of Toll-Like Receptors 4 and 2 to the Cytokine Response to Salmonella enterica Serovar Typhimurium and Staphylococcus aureus in Mice

The contribution of murine Toll-like receptors 2 and 4 (TLR2 and -4, respectively) to cytokine induction by heat-killed bacteria was analyzed in vitro and in vivo. Gram-negative bacteria induced cytokines primarily via TLR4; the contribution of TLR2 was only minor. Neither TLR4 nor, surprisingly, TLR2 was required in the MyD88-dependent response to Staphylococcus aureus

Glycemic control and microvascular complications in adults with type 1 diabetes and long-lasting treated celiac disease: A case-control study

Aims: To investigate whether in type 1 diabetes (T1DM) patients the concomitance of long-lasting celiac disease (CD) treated with a gluten free diet (GFD) impacts glycaemic control and the prevalence/severity of microvascular complications. Methods: A case-control, observational study was performed in 34 patients with T1DM and GFD-treated CD and 66 patients with T1DM alone matched for age, gender, and T1DM duration. Anthropometric parameters, glucose control (HbA1c), status of chronic complications and concomitant autoimmune diseases were evaluated. Results: HbA1c level was similar in T1DM + CD and T1DM alone (7.8 ± 1.0 vs 7.7 ± 1.1%, P = 0.57); insulin requirement was significantly higher in T1DM + CD compared with T1DM (P = 0.04). There were no differences in systolic blood pressure while diastolic blood pressure was significantly lower in T1DM + CD (P = 0.003). The prevalence/severity of microvascular complications was similar between the two groups. Glomerular filtration rate (eGFR) was significantly lower in T1DM + CD (100 ± 20 vs 110 ± 16 ml/min/1.73 m2, P = 0.007). Conclusions: In patients with T1DM, the co-occurrence of long-term GFD-treated CD neither worsens glycemic control nor negatively impacts chronic microvascular complications. However, patients with T1DM + CD have lower eGFR values than those with T1DM alone

Glycemic control and microvascular complications in adults with type 1 diabetes and long-lasting treated celiac disease: A case-control study

Dalbulus maidis (DeLong & Wolcott) (Hemiptera: Cicadellidae) is one of the most important pathogen vectors on maize, but its courtship behavior has never been documented. In the present study, we recorded length of courtship and mating periods and behavioral transitions for D. maidis. According to these observations, we built ethograms for both sexes to create a comprehensive description of their courtship behavior. The mean courtship duration was 110.04 (±66.84) min and the mean mating period was 51.61 (±19.75) min. Both sexes showed similar, stereotyped behavioral transitions. However, females exhibited a lower frequency of several behavioral transitions and behaviors compared with males. Before mating, females were more frequently resting or performing an abdomen movement. Less frequently, they were walking or flapping the wings (wing fanning). Meanwhile, males exhibited three main behaviors before mating; the most frequent was wing fanning, followed by walking and approaching. However, during courtship, rapprochement between individuals of both sexes was not common so it is deduced that physical contact is not essential. In this regard, we discuss possible acoustic and chemical communication during the courtship process of D. maidis. © 2014, Springer Science+Business Media New York

Do patients undergoing MitraClip implantation require routine ICU admission?

OBJECTIVES: Because of its reduced invasiveness, MitraClip (Abbott Vascular, Menlo Park, CA) therapy usually is reserved for patients with extreme left ventricular dysfunction or severe comorbidity contraindicating surgery. The appropriate post-procedural care in this high-risk population is yet to be defined. In this study, the postoperative course of such patients is reported, focusing on early complications and need for intensive care unit (ICU) management. DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis of patients with severe mitral regurgitation undergoing transcatheter mitral valve repair with the MitraClip system in the authors institution was performed. INTERVENTIONS: One hundred thirty patients underwent MitraClip implantation between 2008 and 2012. At the end of the procedure, all patients were admitted to the ICU. MEASUREMENTS AND MAIN RESULTS: Median ICU stay was 0.98 (0.82-1.87) days. Median mechanical ventilation time was 9.5 (6.8-14.1) hours. One hundred one patients (78%) required inotropic support and 13 patients (10%) suffered cardiogenic shock and required intra-aortic balloon pump support. No patient died during the procedure, but 3 patients died in the ICU. Three postoperative course profiles were identified: Fast-track, overnight stay, and critical illness. Twenty-four patients (18.5%) had an uneventful postoperative course, 89 patients (68.5%) suffered minor complications, and 17 patients (13.1%) required intensive care management and organ support. Preoperative serum creatinine (odds ratio [OR] 1.8; p = 0.014), cardiogenic shock (OR 34,8; p = 0.002), ventricular tachycardia (OR 2.8; p = 0.03), and intra procedural inotropes (OR 4; p = 0.001) were correlated with a complicated postoperative course. CONCLUSIONS: A large number of patients undergoing MitraClip could be managed with a fast-track ICU course; however, it still is difficult to predict the postoperative course based on preoperative characteristics