Individual and Relationship-Level Correlates of Transactional Sex Among Adolescent Girls and Young Women in Malawi: A Multilevel Analysis

AIDS and Behavior - Transactional sex increases HIV risk among adolescent girls and young women (AGYW). Understanding the individual and dyadic nature of transactional sex may provide evidence for...     

Resistance to farnesyltransferase inhibitors in Bcr/Abl-positive lymphoblastic leukemia by increased expression of a novel ABC transporter homolog ATP11a

Resistance to cytotoxic drugs frequently emerges during treatment of leukemia with conventional chemotherapy. New classes of anticancer drugs, such as the farnesyltransferase inhibitors (FTIs), show therapeutic promise, but whether cells will easily develop resistance against them is not known. Here, we grew breakpoint cluster region/Abelson murine leukemia (Bcr/Abl) P190 lymphoblasts on stroma and made them resistant to the FTI SCH66336/lonafarnib to model emerging drug resistance in a patient. These cells exhibited greatly increased (> 100-fold) expression levels of a novel ATP (adenosine triphosphate)-binding cassette (ABC) transporter-homologous gene, ATP11A. We showed that overexpression of this gene provided protection against the effects of SCH66336, whereas knockdown of endogenous ATP11a using small interfering RNA (siRNA) made cells more sensitive to this drug. The lymphoblasts that were resistant to this FTI were also more resistant to FTI-276 and to GGTI-298, 2 other structurally similar inhibitors. Surprisingly, the cells were also able to survive higher concentrations of imatinib mesylate, the Bcr/Abl tyrosine kinase inhibitor. However, the cells remained sensitive to vincristine. Our results show that elevated levels of ATP11a can protect malignant lymphoblastic leukemia cells against several novel small molecule signal transduction inhibitors. A determination of the expression levels of this gene may have prognostic value when treatment with such classes of drugs is contemplated.     

Preliminary observation with dronabinol in patients with intractable pruritus secondary to cholestatic liver disease

Pruritus due to cholestatic liver disease can be particularly difficult to manage and frequently is intractable to a variety of medical therapies. The aim of our study is to evaluate the efficacy of delta-9-tetrahydrocannabinol (delta-9-THC) for intractable cholestatic related pruritus (ICRP) that has failed conventional (and unconventional) remedies. Three patients were evaluated for plasmapheresis because of ICRP. All 3 patients had previously been extensively treated with standard therapies for ICRP including: diphenhydramine, chlorpheniramine, cholestyramine, rifampicin, phenobarbital, doxepin, naltrexone, UV therapy, and topical lotions. Even multiple courses of plasmapheresis were performed without any benefit for the intractable pruritus. All patients reported significant decreases in their quality of life, including lack of sleep, depression, inability to work, and suicidal ideations. All patients were started on 5 mg of delta-9-THC (Marinol) at bedtime. All 3 patients reported a decrease in pruritus, marked improvement in sleep, and eventually were able to return to work. Resolution of depression occurred in two of three. Side effects related to the drug include one patient experiencing a disturbance in coordination. Marinol dosage was decreased to 2.5 mg in this patient with resolution of symptoms. The duration of antipruritic effect is approximately 4-6 hrs in all three patients suggesting the need for more frequent dosing. Delta-9-tetrahydrocannabinol may be an effective alternative in patients with intractable cholestatic pruritus.     

Nifedipine: a myocardial protective agent.

The effectiveness of the calcium antagonist nifedipine in preserving postischemic myocardial function and structural integrity was experimentally demonstrated in isolated rabbit hearts, in conscious dogs subjected to myocardial infarction, in open chest anesthetized dogs with normothermic regional ischemia induced for 1 to 2 hours and in dogs undergoing hypothermic global ischemia for 2 hours followed by 2 hours of reperfusion. Nifedipine had a beneficial effect on postischemic myocardial stiffness and mitochondrial calcium accumulation, which were correlated. Administration of nifedipine at the onset of myocardial infarction increased blood flow to ischemic zones of myocardial infarction and resulted in less loss of creatine kinase. It reduced by two- to three-fold the volume of the ischemia-reperfusion injury induced by left anterior descending coronary arterial occlusion and release and preserved indexes of hemodynamic function. Nifedipine was found effective in protecting myocardial performance and structure after 2 hours of global ischemia during hypothermic cardiopulmonary bypass. It is suggested that this agent may be useful as an adjunct to cold cardioplegia in man for enhanced myocardial protection during cardiac surgery.     

Design and results of the antiarrhythmics vs implantable defibrillators (AVID) registry. The AVID Investigators

BACKGROUND: The Antiarrhythmics Versus Implantable Defibrillators (AVID) Study compared treatment with implantable cardioverter-defibrillators versus antiarrhythmic drugs in patients with life-threatening ventricular arrhythmias (VAs). AVID maintained a Registry on all patients, randomized or not, with any VA or unexplained syncope who could be considered for either of the treatment strategies. Trial-eligible arrhythmias were the categories of VF cardiac arrest, Syncopal VT, and Symptomatic VT, below. METHODS AND RESULTS: Of 5989 patients screened, 4595 were registered and 1016 were randomized. Mortality follow-up through 1996 was obtained on the 4219 Registry patients enrolled before 1997 through the National Death Index. Crude mortality rates (mean+/-SD, follow-up, 16.9+/-11.5 months) were: VF cardiac arrest, 17.0% (n=1399, 238 deaths); Syncopal VT, 21.2% (n=598, 127 deaths); Symptomatic VT, 15.8% (n=1065, 168 deaths); Stable (asymptomatic) VT, 19.7% (n=497, 98 deaths); VT/VF with transient/correctable cause, 17.8% (n=270, 48 deaths); and Unexplained syncope, 12.3% (n=390, 48 deaths). CONCLUSIONS: Patients with seemingly lower-risk or unknown-risk VAs (asymptomatic VT, and VT/VF associated with a transient factor) have a (high) mortality similar to that of higher-risk, AVID-eligible VAs. The similar (and poor) prognosis of most patients with VT/VF suggests the need for reevaluation of a priori risk grouping and raises the question of the appropriate arrhythmia therapy for a broad range of patients.     

Polymorphisms in metalloproteinase-9 are associated with the risk for asthma in Mexican pediatric patients

Asthma is characterized by chronic airway inflammation, which induces airway remodelling of the extracellular matrix over time. Matrix metalloproteinases (MMPs) are involved in this process, and single-nucleotide polymorphisms (SNPs) in MMP genes may influence their mRNA expression levels or abilities to bind substrates and inhibitors, thereby contributing to asthma predisposition and severity. MMP-9 is highly expressed in airways and many studies support its involvement in asthma pathogenesis; however the contribution of MMP-9 SNPs is controversial. To investigate whether MMP-9 SNPs are associated with childhood-onset asthma in Mexican patients we conducted a case-control study including 403 children with clinical asthma diagnoses and 426 healthy controls from Mexico. The cases and controls were matched by ethnicity and gender. We found that the SNPs rs2274755, rs17577, and rs3918249 were associated with asthma risk. The most significant associations were with rs2274755 (OR = 2.10, 95% CI 1.31–3.39, P = 0.001) and rs17577 (OR = 2.07, 95% CI 1.29–3.30, P = 0.001); which were in strong linkage disequilibrium. Both SNPs were also associated with atopic asthma (OR = 2.38, 95% CI 1.44–3·96, P = 0.0005). The SNP rs3918249 exhibited a female gender-dependent association with asthma (OR = 1.66, 95% CI 1.14–2.43, P = 0.007). Our results suggest that MMP-9 polymorphisms could play a role in the susceptibility to childhood-onset asthma.     

Intestinal Microbiota Containing Barnesiella Species Cures Vancomycin-Resistant Enterococcus faecium Colonization

Bacteria causing infections in hospitalized patients are increasingly antibiotic resistant. Classical infection control practices are only partially effective at preventing spread of antibiotic-resistant bacteria within hospitals. Because the density of intestinal colonization by the highly antibiotic-resistant bacterium vancomycin-resistant Enterococcus (VRE) can exceed 10⁹ organisms per gram of feces, even optimally implemented hygiene protocols often fail. Decreasing the density of intestinal colonization, therefore, represents an important approach to limit VRE transmission. We demonstrate that reintroduction of a diverse intestinal microbiota to densely VRE-colonized mice eliminates VRE from the intestinal tract. While oxygen-tolerant members of the microbiota are ineffective at eliminating VRE, administration of obligate anaerobic commensal bacteria to mice results in a billionfold reduction in the density of intestinal VRE colonization. 16S rRNA gene sequence analysis of intestinal bacterial populations isolated from mice that cleared VRE following microbiota reconstitution revealed that recolonization with a microbiota that contains Barnesiella correlates with VRE elimination. Characterization of the fecal microbiota of patients undergoing allogeneic hematopoietic stem cell transplantation demonstrated that intestinal colonization with Barnesiella confers resistance to intestinal domination and bloodstream infection with VRE. Our studies indicate that obligate anaerobic bacteria belonging to the Barnesiella genus enable clearance of intestinal VRE colonization and may provide novel approaches to prevent the spread of highly antibiotic-resistant bacteria.     

Pancreatic acinar cells—a normal finding at the gastroesophageal junction? Data from a prospective Central European multicenter study

Pancreatic acinar cells are a well-recognized finding at the gastroesophageal junction, but their histogenesis and biological significance are unclear. From the prospective Central European multicenter histoGERD trial, we recruited 1,071 individuals undergoing gastroscopy for various non-selected reasons. Biopsy material was systematically sampled from the gastroesophageal junction and from the stomach. The study aimed to assess the prevalence of pancreatic acinar cells and to relate their presence to various histologic and clinical features. Overall, pancreatic acinar cells were observed in 184 (17.2 %) participants. Individuals diagnosed with pancreatic acinar cells were slightly younger than those without (median 50 vs. 53 years; p?=?0.009). There was no association with patients’ symptoms and/or complaints or with an endoscopic diagnosis of esophagitis or Barrett’s esophagus. Regarding histology, pancreatic acinar cells were not associated with features of the squamous epithelium indicating reflux disease, such as basal cell hyperplasia, papillary elongation, dilation of intercellular spaces, and inflammatory cell number, but were associated with the presence of cardiac mucosa (p?<?0.001), oxyntocardiac mucosa (p?<?0.001), and intestinal metaplasia (p?=?0.038), respectively. No association with Helicobacter pylori infection or diagnosis of gastritis was noted. In conclusion, pancreatic acinar cells are a common finding at the gastroesophageal junction, and no association with either reflux disease (histologically or endoscopically) or diagnosis of gastritis was observed. These data suggest a congenital rather than an acquired (metaplastic) origin of pancreatic acinar cells at the gastroesophageal junction. This questions the term “pancreatic acinar metaplasia” which is currently widely used for their diagnosis.