Virtual histology intravascular ultrasound in carotid interventions.

PURPOSE: To report early clinical experience with virtual histology intravascular ultrasound (VH IVUS) in carotid endoluminal repair. TECHNIQUE: A 2.9-F, 20-MHz catheter that utilizes computer software to demonstrate the histological components of arteriosclerotic plaque was evaluated during carotid angioplasty and stenting. VH IVUS images were created following a pullback through the carotid stenosis and produced a color-coded map of the different histological constituents of the disease (dark green: fibrous, yellow/green: fibrofatty, white: calcified, and red: necrotic lipid core plaque). CONCLUSION: VH IVUS produces a color-coded map of the different histological components of artery plaque. It has the potential to predict how the plaque is likely to behave at the moment of endoluminal treatment.     

Novel sequence variants in the TMC1 gene in Pakistani families with autosomal recessive hearing impairment

Though many hearing impairment genes have been identified, only a few of these genes have been screened in population studies. For this study, 168 Pakistani families with autosomal recessive hearing impairment not due to mutations in the GJB2 (Cx26) gene underwent a genome scan. Two-point and multipoint parametric linkage analyses were carried out. Twelve families had two-point or multipoint LOD scores of 1.4 or greater within the transmembrane cochlear expressed gene 1 (TMC1) region and were subjected to further screening with direct DNA sequencing. Five novel putatively functional non-synonymous sequence variants, c.830A>G (p.Y277C), c.1114G>A (p.V372M), c.1334G>A (p.R445H), c.2004T>G (p.S668R), and c.2035G>A (p.E679K), were found to segregate within seven families, but were not observed in 234 Pakistani control chromosomes. The variants c.830A>G (p.Y277C), c.1114G>A (p.V372M), and c.1334G>A (p.R445H) occurred at highly conserved regions and were predicted to lie within hydrophobic transmembrane domains, while non-synonymous variants c.2004T>G (p.S668R) and c.2035G>A (p.E679K) occurred in extracellular regions that were not highly conserved. There is evidence that the c.2004T>G (p.S668R) variant may have occurred at a phosphorylation site. One family has the known splice site mutation c.536 -8T>A. The prevalence of non-syndromic hearing impairment due to TMC1 in this Pakistani population is 4.4% (95%CI: 1.9, 8.6%). The TMC1 protein might have an important function in K(+) channels of inner hair cells, which would be consistent with the hypothetical structure of protein domains in which sequence variants were identified.     

The cellular basis of post-burn immunosuppression: macrophages and mediators

Major thermal injury induces the activation of an inflammatory cascade that contributes to the development of subsequent immunosuppression, increased susceptibility to sepsis and multiple organ failure. The productive capacity of macrophages for inflammatory mediators, (i.e., nitric oxide, prostaglandins, TNF-alpha, IL-6 etc.), is profoundly increased post-burn, thereby implicating macrophages in the development of the post-burn immunosuppression. This review will focus on recent findings with regards to the role of macrophages in the development of post-burn immunosuppression with particular emphasis on the role of nitric oxide and prostaglandins.     

Construction of 0D/2D Schottky Heterojunctions of ZnO and Ti3C2 Nanosheets with the Enriched Transfer of Interfacial Charges for Photocatalytic Hydrogen Evolution

The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti₃C₂, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti₃C₂ nanosheets. In constructing these heterojunctions, Ti₃C₂ nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti₃C₂ composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti₃C₂ composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti₃C₂ Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti₃C₂ composition with 30 wt.% of Ti₃C₂, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti₃C₂ as a low-cost co-catalyst.     

Prospective controlled study of posttransfusion hepatitis after cardiac surgery in a large referral hospital in India

ABSTRACT— We studied the risk of post-transfusion hepatitis (PTH) in recipients of blood collected from voluntary donors screened for HBsAg. Two hundred and fifty patients without any previous history of liver disease or transfusion were followed up for 12 months subsequent to cardiac surgery. Thirty-five of them had closed-heart surgery without receiving transfusion and served as controls. The remaining 215 patients received single-point transfusions (mean 4 ± 2.4 units). None of the controls and 15 (6.9%) blood recipients developed PTH. Three (20%) patients had hepatitis-B-virus-induced hepatitis while the remainder (80%) had non A, non B (NANB) hepatitis. The number of units of blood transfused and surrogate markers for development of PTH (donor alanine aminotransferase, anti-HBc and anti-HBs antibody) were not associated with the occurrence of PTH (p>0.05). Nine (60%) of the 15 patients developing PTH were asymptomatic. All the patients recovered from the PTH, except one who died of fulminant hepatitis. At the end of 1 year of follow-up, none of the patients had evidence of chronic hepatitis. Only three (25%) of the patients with NANB-PTH developed anti-hepatitis C virus (HCV) antibody during the follow-up. We conclude that the incidence of PTH in India is similar to other parts of the world and NANB virus was the major cause of the PTH. The absence of chronicity and lack of seroconversion to anti-HCV antibody in the majority of the patients after 1 year of follow-up may suggest the possibility of a NANB virus other than HCV as the major cause of PTH in India.     

Ex Situ Conservation Strategies for <Emphasis Type="Italic">Fritillaria cirrhosa</Emphasis> D. Don (Liliaceae): A Critically Endangered Medicinal Herb of Kashmir Himalaya

Fritillaria cirrhosa D. Don (Liliaceae), a valuable and critically endangered medicinal herb of northwest India, including Jammu and Kashmir, grows in temperate to alpine regions of the Himalaya. The bulbs of the plant are very valuable and are used to cure asthma, tuberculosis, haematemesis and many other health complications. The species faces threat due to multiple factors including habitat loss, over-exploitation for medicine, domestic and commercial trade. The present study was therefore undertaken to develop ex situ conservation strategies and domestication protocols for Fritillaria cirrhosa. The experimental treatments utilized to enhance the regeneration potential, growth and development of Fritillaria cirrhosa include soil texture variation, fertilizer treatment and farmyard manure treatment. The highest values of phenotypic attributes of the plants were recorded in soil: sand combination of 3:1. The plants prefer to grow in low sandy soils. Maximum plant height was attained in a combination of urea (nitrogen), diammonium phosphate (phosphorous) and potash (potassium) fertilizers. The plants depicted an admirably increased height and flower length in 1:1:2 combination and highest flower and leaf numbers in 2:1:1 combination of soil: sand: farmyard manure. Thus, low sandy soil with high organic matter was found to be favourable for better growth and development of the plants of Fritillaria cirrhosa.     

17Beta-estradiol downregulates Kupffer cell TLR4-dependent p38 MAPK pathway and normalizes inflammatory cytokine production following trauma-hemorrhage

Although studies have shown that 17beta-estradiol (estradiol) normalized Kupffer cell function following trauma-hemorrhage, the mechanism by which E2 maintains immune function remains unclear. Activation of Toll-like receptor 4 (TLR4) initiates an inflammatory cascade, involving activation of p38 mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K), and nuclear factor-kappaB (NF-kappaB). This leads to the release of proinflammatory cytokines. Thus, we hypothesized that the salutary effects of estradiol on Kupffer cell function following trauma-hemorrhage are mediated via negative regulation of TLR4-dependent p38 MAPK and NF-kappaB. TLR4 mutant (C3H/HeJ) and wild type (C3H/HeOuJ) mice were subjected to trauma-hemorrhage (mean BP 35+/-5 mmHg approximately 90 min, then resuscitation) or sham operation. Administration of estradiol following trauma-hemorrhage in wild type mice decreased Kupffer cell TLR4 expression as well as prevented the phosphorylation of p38 MAPK and NF-kappaB. This was accompanied by normalization of Kupffer cell production capacities of IL-6, TNF-alpha, macrophage inflammatory protein (MIP)-1alpha, and MIP-2 and the decrease in plasma cytokine levels. In contrast, TLR4 mutant mice did not exhibit the increase in Kupffer cell p38 MAPK and NF-kappaB activation, cytokine production, or the increase in circulating cytokine levels following trauma-hemorrhage. No difference was observed in activation of PI3K among groups. These results suggest that the protective effect of estradiol on Kupffer cell function is mediated via downregulation of TLR4-dependent p38 MAPK and NF-kappaB signaling following trauma-hemorrhage, which prevents the systemic release of cytokines.