Predialysis Kidney Function and Its Rate of Decline Predict Mortality and Hospitalizations After Starting Dialysis

Objective

To determine whether kidney function level and its rate of decline in the immediate predialysis period among veterans transitioning to end-stage renal disease (ESRD) predict postdialysis mortality and hospitalization.

Predicting the electrical conductivity in polymer carbon nanotube nanocomposites based on the volume fractions and resistances of the nanoparticle,interphase, and tunneling regions in conductive networks

Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs). However, earlier models (e.g., the Kovacs model) cannot properly consider the roles of the interphase regions or tunneling properties on the percolation threshold and subsequent conductivity of PCNTs. In this paper, the Kovacs model is further developed by assuming that the CNT, interphase, and tunneling regions are separate phases. Also, some simple equations are provided to calculate the percolation threshold as well as the volume fractions and resistances of the CNT, interphase, and tunneling regions in conductive networks. The experimental conductivity results for several samples are compared with the predictions of the developed model. In addition, the calculations of the developed model at different parameter levels are explained and justified. The conductivity calculations show good agreement with the experimental data. Moreover, the developed model reasonably explains the roles of the different parameters on the conductivity. For example, long, thin, and straight CNTs efficiently improve the conductivity because they form large networks in the nanocomposites. Additionally, a thick interphase enlarges the conductive networks, resulting in a desirable conductivity. The conductivity of PCNTs only depends on the tunneling resistance; this is the case because the poor resistance/significant conductivity of the CNT and interphase regions do not influence the conductivity. The developed equations can replace conventional approaches for predicting the conductivity of nanocomposites.

Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs).     

Hemostatic efficacy of hydrophilic wound dressing after transradial catheterization

Here, we evaluate the efficacy of the Clo-Sur PAD nonwoven hydrophilic wound dressing (HWD) on hemostasis in an arterial-access site after transradial percutaneous coronary angiography compared with the RadiStop compression device (CD). Eighty patients who had undergone transradial coronary angiography with or without intravascular ultrasound were randomly assigned to the HWD or CD group. The time required to achieve hemostasis was measured, and the incidence of vascular complications was assessed. No significant differences in clinical and procedural characteristics were observed between the HWD group (n = 40) and the CD group (n = 40). A significant reduction in the time required to achieve hemostasis (58.7 +/- 32.6 minutes versus 131.3 +/- 59.1 minutes; p < 0.001) was associated with the use of HWD. The incidence of vascular complications was similar in both groups (5% for HWD versus 2.5% for CD; p = 0.500). No major complications, such as large hematoma or acute radial occlusion, occurred in the HWD group. In conclusion, HWD represents a safe alternative to the compression method. Hemostasis can be achieved more quickly using HWD, with no increase in access site complications, as compared to CD.     

Bortezomib down-regulates the cell-surface expression of HLA class I and enhances natural killer cell-mediated lysis of myeloma

Human leukocyte antigen class I molecules expressed by tumor cells play a central role in the regulation of natural killer (NK) cell-mediated immune responses. The proteasome inhibitor bortezomib has demonstrated significant activity in multiple myeloma (MM). We hypothesized that treatment of MM with bortezomib results in the reduction of cell-surface expression of class I and thereby sensitizes MM to NK cell-mediated lysis. Here we report that bortezomib down-regulates class I in a time- and dose-dependent fashion on all MM cell lines and patient MM cells tested. Downregulation of class I can also be induced in vivo after a single dose of 1.0 mg/m(2) bortezomib. Bortezomib significantly enhances the sensitivity of patient myeloma to allogeneic and autologous NK cell-mediated lysis. Further, the level of decrease in class I expression correlates with increased susceptibility to lysis by NK cells. Clinically relevant bortezomib concentrations do not affect NK-cell function. Our findings have clear therapeutic implications for MM and other NK cell-sensitive malignancies in the context of both allogeneic and autologous adoptively transferred NK cells.     

An evaluation of web-based informations about gastroesophageal reflux diseases in Korea]

BACKGROUND/AIMS: Internet has become an important source of medical information not only for medical personnels but also for patients. The aim of this study was to evaluate the quality of internet based medical information about 'gastroesophageal reflux' or 'reflux esophagitis' in Korea. METHODS: The first 15 internet sites using the key words 'gastroesophageal reflux' or 'reflux esophagitis' were retrieved from the 7 most frequently used internet search engines. The quality of information from a total of 108 websites was evaluated using a checklist. RESULTS: Among total 108 sites related to 'gastroesophageal reflux' or 'reflux esophagitis', fifty-six sites (51.8%) were made by hospitals or clinics and 94 sites (87.0%) were made for patients. Of the 108 sites, eleven web sites (10.1%) had more than three JAMA benchmarks (authorship, references, currency, and disclosure). Higher quality sites (at least three JAMA benchmarks) were less likely to contain inaccurate information than lower quality sites (fewer than three JAMA benchmarks)-3/11 (27.2%) vs. 60/97 (61.9%) (p<0.01). Despite the fact that articles in the literature emphasized an insufficient evidence to support an association between the lifestyle, dietary behaviors, and GERD, such guidelines continue to be recommended as first-line therapy in most websites. CONCLUSIONS: Informations about gastroesophageal reflux disease were incomplete in the majority of medical web sites. These would bring about confusion to patients seeking for an information about GERD through the internet. There is a need for better sources in evidence based informations about gastroesophageal reflux diseases on the web.     

Unusual variant of atrioventricular nodal reentrant tachycardia.

Electrophysiologic study in a patient with supraventricular tachycardia revealed an unusual activation pattern in the coronary sinus (CS) electrodes. Pacing maneuvers confirmed the tachycardia was a slow-slow AV nodal reentrant tachycardia with double potentials in the distal CS electrodes due to an earlier left atrial signal (50 ms) and later CS musculature activation. The left-sided AV nodal inputs were successfully ablated from within the CS.     

Insulin resistance and C-reactive protein as independent risk factors for non-alcoholic fatty liver disease in non-obese Asian men

BACKGROUND AND AIM: Although insulin resistance is often considered the link between obesity and non-alcoholic fatty liver disease (NAFLD), the role of insulin resistance, independent of obesity, as a NAFLD risk factor in non-obese men has been less well established. Systemic inflammation may be accompanied by insulin resistance in healthy subjects. The goal of the present study was to examine if insulin resistance and systemic inflammatory markers are independent predictors of NAFLD in non-obese men. METHODS: The authors conducted a cross-sectional survey of 120 patients with NAFLD and 240 controls matched by age and body mass index. Controls had no evidence of alcohol abuse, hepatitis B or C, obesity, or previous history of diabetes, fasting hyperglycemia or hypertension. Diagnosis of NAFLD was based on an elevated alanine aminotransferase level and sonographic evidence of a fatty liver. Insulin resistance was determined using a homeostasis model assessment (HOMA-IR). RESULTS: The age-adjusted risk of developing NAFLD was strongly associated with the elevated levels in measurements of uric acid, fasting blood sugar, triglycerides, apolipoprotein B, C-reactive protein (CRP) and HOMA-IR, and decreased levels of high density lipoprotein cholesterol and apolipoprotein A-I. Multivariate analysis based on univariate analysis indicated that an increase in CRP (odds ratio [OR] = 1.37; 95% confidence interval [CI]: 1.06-1.77) per 1 SD (1.48 mg/L) and HOMA-IR (OR = 2.28; 95% CI: 1.67-3.11) per 1 SD (0.63) were independent risk factors for NAFLD. CONCLUSION: Insulin resistance and systemic inflammatory response are of key importance for inducing NAFLD, particularly in apparently healthy non-obese men.     

Prognostic factors in allogeneic transplantation for patients with high-risk multiple myeloma after reduced intensity conditioning

OBJECTIVES: The aim of this study was to identify prognostic factors for outcome of high-risk patients with multiple myeloma after allogeneic transplantation prepared by reduced intensity conditioning (RIC). MATERIALS AND METHODS: Data from 45 consecutive patients (median age 52 years, range 38-68), who received grafts from a sibling (n = 34) or unrelated donor (n = 11) were analyzed. Fourteen patients received an RIC allotransplant while chemosensitive (>/=partial remission [PR]), whereas 31 chemoresistant patients (相似文献   

The BRAF mutation is not associated with poor prognostic factors in Korean patients with conventional papillary thyroid microcarcinoma

BACKGROUND: The BRAF(V600E) mutation, the most common genetic alteration reported in papillary thyroid carcinoma, has been associated with poor prognostic factors. AIM: To determine whether the presence of the BRAF(V600E) mutation is associated with poor prognosis in Korean patients with conventional papillary thyroid microcarcinoma (micro-PTC). PATIENTS AND METHODS: DNA was extracted from paraffin-embedded thyroid tumour specimens taken from 60 patients with conventional micro-PTC, as well as from nine patients with follicular variant papillary carcinoma, six with nodular hyperplasia, four with follicular carcinoma (including one with Hürthle cell carcinoma), four with follicular adenoma (including two with Hürthle cell adenoma) and one each with medullary carcinoma, poorly differentiated carcinoma and anaplastic carcinoma. The presence of the BRAF(V600E) mutation was determined by polymerase chain reaction (PCR) amplification of exon 15 followed by direct sequencing. RESULTS: The BRAF(V600E) mutation was detected in tumour samples from 31 of 60 conventional micro-PTC patients (52%), but was not detected in patients with other types of thyroid tumours. The age distribution, tumour size, extrathyroid extension, multifocality and staging did not differ significantly between patients with and without the BRAF(V600E) mutation. CONCLUSION: In Korean patients with conventional micro-PTC, the presence of the BRAF(V600E) mutation was not significantly associated with prognostic factors.     

Metabolic bifunctionality of Rv0812 couples folate and peptidoglycan biosynthesis in Mycobacterium tuberculosis

Comparative sequence analysis has enabled the annotation of millions of genes from organisms across the evolutionary tree. However, this approach has inherently biased the annotation of phylogenetically ubiquitous, rather than species-specific, functions. The ecologically unusual pathogen Mycobacterium tuberculosis (Mtb) has evolved in humans as its sole reservoir and emerged as the leading bacterial cause of death worldwide. However, the physiological factors that define Mtb’s pathogenicity are poorly understood. Here, we report the structure and function of a protein that is required for optimal in vitro fitness and bears homology to two distinct enzymes, Rv0812. Despite diversification of related orthologues into biochemically distinct enzyme families, rv0812 encodes a single active site with aminodeoxychorismate lyase and D–amino acid transaminase activities. The mutual exclusivity of substrate occupancy in this active site mediates coupling between nucleic acid and cell wall biosynthesis, prioritizing PABA over D-Ala/D-Glu biosynthesis. This bifunctionality reveals a novel, enzymatically encoded fail-safe mechanism that may help Mtb and other bacteria couple replication and division.