Lens epithelial cell density and histomorphological study in cataractous lenses.

Human epithelial cell density was determined from flat preparation of 195 cataractous lenses from 108 males and 87 females between 30 and 80 years of age. The mature cataracts had significantly lower cell counts than the other cataracts. Cell density was significantly higher in the females than in the males. Morphohistological study of the epithelia was focused on the following cataract types: (1) nuclear, (2) posterior subcapsular, (3) mature, (4) mixed, (5) hypermature, and (6) black. The major cataractous changes in all types involved vacuolization of the cytoplasm. The mature types of cataractous epithelia showed 56% superimposed cells; the epithelia in nuclear, posterior subcapsular, and black cataracts showed between 6% and 16%. In the hypermature cataracts, four of five tissues analyzed showed superimposed cells. The superimposed areas are probably the source of increased and altered cell activity. We propose that the metaplastic processes leading to posterior capsular opacification originate from these areas. The majority of nuclear and black cataracts were almost similar to the normal human lens epithelium with more or less uniform distribution of cells. Nucleus shrinkage (5 microns) was more evident in nuclear cataracts; in subcapsular cataracts most of the nuclei were large (average 9 microns diameter). Variation in morphological changes like vacuolization of cytoplasm and nuclei, pyknotic nuclei, and superimposed cells was more evident in the mixed type of cataracts.     

Cadmium-induced lipid peroxidation in rat liver slices: A possible involvement of hydroxyl radicals

Cadmium-induced lipid peroxidation (LPO) in the presence of various hydroxyl radical-generating media was studied in rat liver slices. In the absence of such media, Cd showed an inhibitory action on LPO in vitro. Cd-induced LPO in liver slices in the presence of OH radical-generating media was inhibited by antioxidants. The findings indicate that Cd induced LPO as a result of the presence of transition metal ions and the generation of hydroxyl radicals.     

Safety of carotid artery stenting for symptomatic carotid artery disease: a meta-analysis.

AIMS: Clinical trials comparing carotid artery stenting (CAS) with carotid endarterectomy (CEA) for patients with symptomatic carotid artery disease have produced conflicting results. We performed a meta-analysis to systematically evaluate currently available data by comparing CAS with CEA in patients with symptomatic carotid artery disease. METHODS AND RESULTS: We searched MEDLINE, Embase, ISI Web of Knowledge, Current Contents, International Pharmaceutical Abstracts databases, the Cochrane Central Register of Controlled Trials, and scientific meeting abstracts up to 31 October 2006 and then calculated summary risk ratios (RRs) for mortality, stroke, disabling stroke, and death using random- and fixed-effect models. Data from five trials with 2122 patients were pooled. There was no difference in risk of 30-day mortality (summary RR 0.57, 95% CI 0.22-1.47, P = 0.25), stroke (summary RR 1.64, 95% CI 0.67-4.00, P = 0.34), disabling stroke (summary RR 1.67, 95% CI 0.50-5.62, P = 0.50), death and stroke (summary RR 1.54, 95% CI 0.81-2.92, P = 0.19), or death and disabling stroke (summary RR 1.19, 95% CI 0.57-2.51, P = 0.64) among patients randomized to CAS, compared with CEA. CONCLUSIONS: No significant differences could be identified between CAS and CEA in the treatment of patients with symptomatic carotid artery disease. Larger randomized controlled trials are warranted to compare the two strategies.     

Dissociation of the neuronal regulation of bone mass and energy metabolism by leptin in vivo

The leptin regulation of bone remodeling, which has been documented through studies of loss-of-function mutations of this hormone or of its receptor in mice and humans, still raised several unanswered questions. For instance, it has been assumed but not formally demonstrated that this regulation occurs through neuronal means. Likewise, it has not been possible until now to dissociate the influence leptin exerts on appetite and energy expenditure from this function. We show here through mouse genetic studies that a deletion of the leptin receptor in neurons results in an increase in bone formation and bone resorption, resulting in a high bone mass as seen in leptin-deficient mice. In contrast, the same deletion in osteoblasts only does not influence bone remodeling. Furthermore, through the use of l/l mice, a model of gain of function in leptin signaling harboring a Y985L substitution in the leptin receptor, we show that leptin signaling inhibits bone mass accrual by up-regulating sympathetic activity independently of any change in appetite or energy expenditure. This work establishes that in vivo leptin regulates bone mass accrual by acting through neuronal means and provides a direct demonstration that this function of leptin can occur independently of its regulation of energy metabolism.     

STRUBBELIG defines a receptor kinase-mediated signaling pathway regulating organ development in Arabidopsis

An open question remains as to what coordinates cell behavior during organogenesis, permitting organs to reach their appropriate size and shape. The Arabidopsis gene STRUBBELIG (SUB) defines a receptor-mediated signaling pathway in plants. SUB encodes a putative leucine-rich repeat transmembrane receptor-like kinase. The mutant sub phenotype suggests that SUB affects the formation and shape of several organs by influencing cell morphogenesis, the orientation of the division plane, and cell proliferation. Mutational analysis suggests that the kinase domain is important for SUB function. Biochemical assays using bacterially expressed fusion proteins indicate that the SUB kinase domain lacks enzymatic phosphotransfer activity. Furthermore, transgenes encoding WT and different mutant variants of SUB were tested for their ability to rescue the mutant sub phenotype. These genetic data also indicate that SUB carries a catalytically inactive kinase domain. The SUB receptor-like kinase may therefore signal in an atypical fashion.     

Seroprevalence of HIV infection among leprosy patients in Agra, India: trends and perspective

This study compares the results of HIV seroprevalence, which was carried out in two phases, i.e., 1989 to 1993 and 1999 to 2004. Although the number of leprosy patients screened for HIV infection in the second phase is less (2125) as compared to those screened during the first phase (4025), a rise in HIV infection from 0.12% to 0.37% is certainly disturbing since this area appears to be endemic for both the infections. During the study period, the Out Patient department attendance of a few types of leprosy patients like borderline and borderline lepromatous have risen, whereas others like borderline tuberculoid and polar tuberculoid have declined in the second phase as compared to that of the first phase. The trend over a decade suggests that HIV infection is low among the leprosy patients when compared with other risk groups. Follow-up of these patients at an interval of six months, revealed that none of them downgraded into a severe form of leprosy nor developed ARC or AIDS. In this study, it appears that neither infection precipitated the other. The occurrence of downgradation as well as reversal reactions and neuritis (both chronic and acute) was not observed among the leprosy patients. None of them developed erythema nodosum leprosum reactions. Similarly, the HIV-positive leprosy cases did not develop either AIDS related complex (ARC) or full blown case of AIDS.