Thermorheologic Properties of Aqueous Solutions and Gels of Tetronic 1508

The rheologic properties of aqueous solutions and gels of Tetronic 1508 were investigated as a function of polymer concentration and temperature utilizing rotational viscometry. Below the sol–gel transition temperature the polymer solutions were low in viscosity and exhibited Newtonian rheologic behavior even at concentrations of 20 and 25% (w/w). Upon sol–gel transition, the more concentrated polymer solutions underwent a dramatic four- to five-orders of magnitude increase in viscosity, resulting in the formation of a rigid gel structure. Above the sol-gel transition temperature, the gels displayed pseudoplastic and plastic rheologic properties and the viscosity of the gels remained at a relatively constant value over a wide temperature range. Eventually, the thermal energy of the system exceeded the bonding forces within the gel structure, resulting in a gel–sol transition which was marked by a dramatic decrease in the viscosity of the system. Above the gel–sol transition temperature, the system reverted to a Newtonian fluid with viscosities very similar to those found for the Tetronic 1508 solutions at temperatures below the sol–gel transition temperature. The thermodynamic implications of the gel–sol transition are discussed.     

Sexually Dimorphic Patterns of Episomal rAAV Genome Persistence in the Adult Mouse Liver and Correlation With Hepatocellular Proliferation

Recombinant adeno-associated virus vectors (rAAVs) show exceptional promise for liver-targeted gene therapy, with phenotype correction in small and large animal disease models being reported with increasing frequency. Success in humans, however, remains a considerable challenge that demands greater understanding of host–vector interactions, notably those governing the efficiency of initial gene transfer and subsequent long-term persistence of gene expression. In this study, we examined long-term enhanced green fluorescent protein (eGFP) expression and vector genome persistence in the mouse liver after rAAV2/8-mediated gene transfer in early adulthood. Two intriguing findings emerged of considerable scientific and clinical interest. First, adult female and male mice showed distinctly different patterns of persistence of eGFP expression across the hepatic lobule after exhibiting similar patterns initially. Female mice retained a predominantly perivenous pattern of expression, whereas male mice underwent inversion of this pattern with preferential loss of perivenous expression and relative retention of periportal expression. Second, these changing patterns of expression correlated with sexually dimorphic patterns of genome persistence that appear linked both spatially and temporally to underlying hepatocellular proliferation. Observation of the equivalent phenomenon in man could have significant implications for the long-term therapeutic efficacy of rAAV-mediated gene transfer, particularly in the context of correction of liver functions showing metabolic zonation.     

A new metabolic scoring system for analyzing the risk of hypertensive disorders of pregnancy

Objective  

The aim of this study was to investigate the relationship between some components of metabolic syndrome (MS) and pregnancy induced hypertension (PIH).     

The Missouri Elks Mobile Dental Program–Dental Care for Developmentally Disabled Persons

This article describes the origins, funding, organization, operation, utilization, and outreach program of a statewide mobile dental program for the disabled in Missouri. The article includes information based on analysis of productivity reports and patient records. Comparisons are made between the utilization by mentally retarded (MR) and other disabled patients (MCCS), their county of residence, and the location where service was provided (rural vs urban). The mean number of dental procedures provided per client was 7.3. More procedures (8.35) were provided to urban clients than rural clients (5.81). The utilization rate of urban MR clients was 63.9 percent, compared to 60 percent for rural MR clients. Other findings show 10.7 percent urban MCCS clients utilized the mobile dental program, versus 13.5 percent of the rural MCCS clients. The budgeted expenditures for providing care to this underserved group were $46,000 less than the estimated value of dental care provided in a private practice setting.     

Epidemiology and diagnosis of migraine in children

Migraine headache occurs frequently in children and adolescents but is often not recognized. This underdiagnosis or misdiagnosis results in inappropriate and potentially ineffective treatments. A variety of factors may contribute to this deficiency, including limitations in the current standardized criteria, as well as patient, parent, and care providers’ misassumption as to the etiology. The standardized criteria that have been developed to assist with the recognition and accurate diagnoses have recently been revised (the International Classification of Headache Disorders II). These criteria provide the scientific basis for the study of headache, including the determination of the incidence and prevalence of pediatric migraine.     

Hallux Valgus Evaluation on MRI: Can Measurements Validated on Radiographs Be Used?

Hallux valgus (HV) is a common deformity of the great toe affecting >23% of adults in the United States. The severity of the deformity is traditionally analyzed using radiographs to determine measurements such as the HV and intermetatarsal angles. We sought to determine the relationship between the radiographic and magnetic resonance imaging (MRI) measurements because this is not yet known. Two of us analyzed a series of 56 consecutive patients who had had radiographs and MRI performed on the same foot between April 27, 2015 and March 9, 2016 and who satisfied all other inclusion and exclusion criteria (age 18 to 100 years, no history of recent foot trauma, and no metal hardware in the foot). We found excellent interreader reliability (intraclass correlation 0.89 to 0.96) and intermodality agreement (intraclass correlation 0.83 to 0.91). The HV angle measured 15.0°?±?8.8° on the MRI scans and 13.8°?±?8.7° on the radiographs (mean difference ?1.15°?±?3.89°), and the intermetatarsal angle was 9.0°?±?3.1° on the MRI scans and 8.8°?±?2.9° on the radiographs (mean difference ?0.22°?±?2.10°). The HV measurements were reliable on both radiographs and MRI for the range of values tested. Small intermodality statistically significant differences in HV angle measurements were found; however, these might not be enough to be clinically significant.     

Telavancin, a multifunctional lipoglycopeptide, disrupts both cell wall synthesis and cell membrane integrity in methicillin-resistant Staphylococcus aureus

The emergence and spread of multidrug-resistant gram-positive bacteria represent a serious clinical problem. Telavancin is a novel lipoglycopeptide antibiotic that possesses rapid in vitro bactericidal activity against a broad spectrum of clinically relevant gram-positive pathogens. Here we demonstrate that telavancin's antibacterial activity derives from at least two mechanisms. As observed with vancomycin, telavancin inhibited late-stage peptidoglycan biosynthesis in a substrate-dependent fashion and bound the cell wall, as it did the lipid II surrogate tripeptide N,N'-diacetyl-L-lysinyl-D-alanyl-D-alanine, with high affinity. Telavancin also perturbed bacterial cell membrane potential and permeability. In methicillin-resistant Staphylococcus aureus, telavancin caused rapid, concentration-dependent depolarization of the plasma membrane, increases in permeability, and leakage of cellular ATP and K(+). The timing of these changes correlated with rapid , concentration-dependent loss of bacterial viability, suggesting that the early bactericidal activity of telavancin results from dissipation of cell membrane potential and an increase in membrane permeability. Binding and cell fractionation studies provided direct evidence for an interaction of telavancin with the bacterial cell membrane; stronger binding interactions were observed with the bacterial cell wall and cell membrane relative to vancomycin. We suggest that this multifunctional mechanism of action confers advantageous antibacterial properties.