Further Observations on Orbital

Vaginal epithelial cells mature from basal to intermediate to superficial cells. Estrogen causes more superficial cells to be shed, and the proportion of exfoliated cell types is called a Maturation Index. This index helps clinicians manage dysfunctional bleeding, evaluate hormone change at menopause or prepuberty, and predict ovulation.     

Hepatic Stellate Cells and Liver Retinoid Content in Alcoholic Liver Disease in Humans

Body retinoids are stored in the lipid droplets of hepatic stellate (Ito) cells. In chronic liver disease, the stellate cells differentiate into myo-fibroblast-like cells, a process whereby they lose their retinoid-con-taining lipid droplets. We studied the relation between liver retinoid content, the number of lipid droplets per stellate cell, and the number of stellate cells per mm² in human alcoholic liver disease. Semithin sections of liver biopsies from normal subjects and patients with early (steatosis, inflammation, and mild fibrosis) and late (cirrhosis and cirrhosis with acute alcoholic hepatitis) alcoholic liver disease were morphometrically evaluated. Liver retinoid content was determined by HPLC. In normal patients, liver retinoid content was 901 ± 213 lU/g of liver (mean ± SEM). There was a decrease in liver retinoid content in early alcoholic liver disease (409 ± 50 IU/g) and a further reduction in cirrhosis (153 ± 50 IU/g). In patients with acute alcoholic hepatitis, retinoid content was strikingly low (5.2 ± 1.8 IU/g). There was a progressive decrease in the number of stellate cells per mm² associated with progressive liver damage. We found a fair correlation between the number of stellate cells per mm² and liver retinoid content in all patient groups (overall correlation: 0.71). In normal subjects, the mean number of lipid droplets per stellate cell was 7.4 ± 0.7. In patients with early alcoholic liver disease and in patients with alcoholic cirrhosis, this value was increased to 13.6 ± 0.8 and 10.4 ± 2.0, respectively. In patients with acute alcoholic hepatitis, only a few lipid droplets were present (4.2 ± 0.5). There was a good correlation between liver retinoid content and mean number of lipid droplets in normal patients (r= 0.58). In alcoholic cirrhosis, however, correlation was poor (r= 0.34). In early alcoholic liver disease, the correlation was absent (r= 0.004). In conclusion, the major finding of our study is that the correlation between the mean number of lipid droplets per stellate cell and liver retinoid content varies according to the hepatic pathology considered. Marked lipid droplet accumulation occurs in stellate cells in early alcoholic liver disease and, to a lesser extent, in alcoholic cirrhosis, but there is no correlation between the mean number of lipid droplets per stellate cell and liver retinoid content. Therefore, not retinoids but probably lipids are responsible for the accumulation of lipid droplets. We also find that there is a fair correlation between the number of stellate cells per mm² and liver retinoid content in all patient groups. Finally, we confirm the decrease in hepatic retinoid content that occurs in alcoholic liver disease in humans, even at the early stages of the disease.     

Postoperative nausea and vomiting – a narrative review of pathophysiology,pharmacotherapy and clinical management strategies

Introduction: Postoperative nausea and vomiting (PONV) are common complications concerning patients undergoing general anesthesia. Intensive research was performed during the last two decades in order to develop therapeutic and prophylactic strategies to prevent this complication.

Areas covered: This article reviews the pathophysiology as well as pharmacological aspects of PONV prophylaxis and treatment. Relevant strategic aspects for pharmacological prophylaxis of PONV are discussed and clinical standard operating procedures are presented.

Expert opinion: The expert opinion focuses on poor implementation of actual PONV guidelines and future considerations.     

The regulation of leptin gene expression in the C6 glioblastoma cell line

The hormone leptin is implicated in the regulation of appetite and body weight in rodents, primates and humans. We reported that the leptin gene (ob) is expressed in the brain, but the factors which control ob expression in the central nervous system are not known. We previously showed that brain-derived rat C6 glioblastoma cells express ob mRNA and protein. In the present study we examined the regulation of ob expression in C6 cells. Leptin and leptin receptor immunoreactivity was detected in C6 cells, suggesting a possible autocrine role for leptin. The identity of the leptin immunoreactivity (OB-ir) in C6 cells was confirmed by immunoprecipitation and Western blotting using two leptin specific polyclonal antibodies. Using RT-PCR analysis a product of the expected size for the short, but not the long, leptin receptor isoform was detected in C6 cells. Cells were maintained in serum-free (SF) media for 0-24 h in the presence of various regulators of leptin expression. Leptin mRNA levels were significantly higher in cells treated with dbcAMP (1 mM), IGF 1 (100 ng/ml) or insulin (5 microg/ml) compared to SF controls. In contrast, corticosterone (10(-7)M) reduced leptin mRNA. In the presence of dbcAMP, C6 cells undergo a dramatic alteration in morphology which is coincident with an apparent increase in the number of leptin-ir nuclei and an increase in leptin immunoreactivity. In contrast to C6 cells, glucocorticoids are reported to increase leptin levels in adipocytes/adipose tissue, while increases in intracellular cAMP levels are reported to reduce leptin levels. Overall, our in vitro data suggest that the regulation of leptin gene expression in C6 glioblastoma cells is different from that in adipocytes.     

Glucose-6-phosphate dehydrogenase modulates cytosolic redox status and contractile phenotype in adult cardiomyocytes

Reactive oxygen species (ROS)-mediated cell injury contributes to the pathophysiology of cardiovascular disease and myocardial dysfunction. Protection against ROS requires maintenance of endogenous thiol pools, most importantly, reduced glutathione (GSH), by NADPH. In cardiomyocytes, GSH resides in two separate cellular compartments: the mitochondria and cytosol. Although mitochondrial GSH is maintained largely by transhydrogenase and isocitrate dehydrogenase, the mechanisms responsible for sustaining cytosolic GSH remain unclear. Glucose-6-phosphate dehydrogenase (G6PD) functions as the first and rate-limiting enzyme in the pentose phosphate pathway, responsible for the generation of NADPH in a reaction coupled to the de novo production of cellular ribose. We hypothesized that G6PD is required to maintain cytosolic GSH levels and protect against ROS injury in cardiomyocytes. We found that in adult cardiomyocytes, G6PD activity is rapidly increased in response to cellular oxidative stress, with translocation of G6PD to the cell membrane. Furthermore, inhibition of G6PD depletes cytosolic GSH levels and subsequently results in cardiomyocyte contractile dysfunction through dysregulation of calcium homeostasis. Cardiomyocyte dysfunction was reversed through treatment with either a thiol-repleting agent (L-2-oxothiazolidine-4-carboxylic acid) or antioxidant treatment (Eukarion-134), but not with exogenous ribose. Finally, in a murine model of G6PD deficiency, we demonstrate the development of in vivo adverse structural remodeling and impaired contractile function over time. We, therefore, conclude that G6PD is a critical cytosolic antioxidant enzyme, essential for maintenance of cytosolic redox status in adult cardiomyocytes. Deficiency of G6PD may contribute to cardiac dysfunction through increased susceptibility to free radical injury and impairment of intracellular calcium transport. The full text of this article is available online at http://www.circresaha.org.     

Clinical importance of understanding vascular biology

A comprehensive understanding of the biology of the vessel wall has fostered the discovery of novel therapeutic interventions. The vascular endothelium, smooth muscle cells, and adventitial fibroblasts exist in a tightly regulated milieu in which extravascular stimuli produce coordinated physiologic actions in each cell type, which, in turn, modulate integrative responses in the vessel wall. When vascular injury occurs as a result of biochemical or mechanical forces, such as in hypertension, atherosclerosis, or restenosis, normal homeostatic mechanisms are perturbed, and if compensatory mechanisms are overwhelmed, the vessel becomes dysfunctional. These states are characterized by changes in regulatory molecules that stimulate aberrant responses. Recent advances in molecular biology, including gene transfer and antisense technology, have been used successfully to replete or diminish these factors and restore vascular homeostasis. We present an overview of basic vascular biology as it relates to relevant clinical vascular pathobiology and molecular therapeutics.     

Ethical Issues and Management of Fetal Hemolytic Anemia Caused by Anti-Rh17 in a Multipara with Rare −D– Phenotype

BackgroundThe development of allo-anti-Rh17 (anti-Hr0) in a −D– phenotype whose red blood cells (RBCs) lack CcEe antigens is most likely triggered by transfusion, transplantation, or pregnancy. Gene conversion is the predominating factor in generating RHD-CE-D and RHCE-D-CE hybrids like −D–.MethodsWe report here immunohematological and obstetrical data from 2 of the 5 pregnancies of a 24-year-old woman presenting with the −D– phenotype with anti-Rh17. Blood group typing, antibody screening, antibody differentiation, direct antiglobulin test (DAT), and antibody titers were performed by routine gel technology and tube testing. Additionally, molecular genetic analysis was performed. Fetal surveillance was done by sonographic evaluation of the fetal middle cerebral artery peak systolic velocity (MCA-PSV).ResultsBlood group typing showed O, C-c-D+E-e- and the DAT was negative. DNA sequencing revealed homozygosity for an RHCE-D(3–9)-CE null allele. Anti-Rh17 titers in the fourth pregnancy remained between 1:8 and 1:128, and no signs for a fetal anemia were observed. However, in the fifth pregnancy, the antibody titers increased up to 1:4,096. Signs of moderate fetal anemia were detected and cesarean section was performed at 34 + 6 weeks of gestation. The newborn presented with hemolytic anemia (cord blood hemoglobin [Hb] = 8.5 mg/dL). She received 2 compatible (small) packed RBC concentrates, phototherapy, and intravenous immunoglobulins.ConclusionOur case shows that the risk for hemolytic complications increases with the number of pregnancies of sensitized women. Only people who also lack CcEe antigens are compatible as donors. The role of such rare donors as lifesavers, their freedom, and voluntariness conflict with the urgent need for compatible blood.     

Blood flow velocity vector field reconstruction from dual-beam bidirectional Doppler OCT measurements in retinal veins

In this paper, we demonstrate the possibility to reconstruct the actual blood flow velocity vector field in retinal microvessels from dual-beam bidirectional Doppler optical coherence tomography measurements. First, for a better understanding of measured phase patterns, several flow situations were simulated on the basis of the known dual beam measurement geometry. We were able to extract the vector field parameters that determine the measured phase pattern, allowing for the development of an algorithm to reconstruct the velocity vector field from measured phase data. In a next step, measurements were performed at a straight vessel section and at a venous convergence; the obtained phase data were evaluated by means of the new approach. For the straight vessel section, the reconstructed flow velocity vector field yielded a parabolic flow. For the venous convergence, however, the reconstructed vector field deviated from a parabolic profile, but was in very good accordance with the simulated vector field for the given vessel geometry. The proposed algorithm allows predictions of the velocity vector field. Moreover, the algorithm is also sensitive to directional changes of the flow velocity as small as <1°, thereby offering insight in the flow characteristics of the non-Newtonian fluid blood in microvessels.OCIS codes: (110.4500) Optical coherence tomography, (170.2655) Functional monitoring and imaging, (280.2490) Flow diagnostics     

Protease mutations in HIV-1 non-B strains infecting drug-naive villagers in Cameroon

To describe the presence of protease inhibitor (PI) resistance-associated mutations and subtype distribution in drug-naive villagers of six provinces of Cameroon, we sequenced the protease (PR) gene (297 bp) of 128 viruses. Secondary PI resistance-associated mutations were identified at five sites: L10I/V (16%), K20R (8%), M36I (98%), L63P (13%), and V77I (6%). No primary mutation in the PR was identified. Of the 128 specimens analyzed, subtypes A (11%), C(2%), D (6%), F2 (3%), G (6%), H (0.8%), J (6%), and CRF02_AG (60%) were identified. The mutations identified were not characteristic to any particular subtype. The absence of primary mutations, in addition to the few secondary mutations, gives good perspectives for PI treatment interventions in these rural areas.