Vitamin supplements to women using oral contraceptives (studies of vitamins B1, B2, B6 and A)

Additional requirement of pyridoxine, thiamin and riboflavin necessary to prevent a decline in the nutritional status of these vitamins in women using an oral contraceptive — Ovral (ethinyl estradiol 0.05 mg and dl-norgestrel 0.5 mg) was examined. Ten mg of pyridoxine daily could mitigate the defect in tryptophan metabolism to a large extent. This amount could prevent the defect in erythrocyte aspartate amino transferase activity. Daily supplements of 3 mg thiamin and 2 mg riboflavin could prevent the decline in the nutritional status of these vitamins. Higher amounts of riboflavin would, however, be required to correct the initial deficiency of the vitamin.     

Anthrax edema toxin impairs clearance in mice

The anthrax edema toxin (ET) of Bacillus anthracis is composed of the receptor-binding component protective antigen (PA) and of the adenylyl cyclase catalytic moiety, edema factor (EF). Uptake of ET into cells raises intracellular concentrations of the secondary messenger cyclic AMP, thereby impairing or activating host cell functions. We report here on a new consequence of ET action in vivo. We show that in mouse models of toxemia and infection, serum PA concentrations were significantly higher in the presence of enzymatically active EF. These higher concentrations were not caused by ET-induced inhibition of PA endocytosis; on the contrary, ET induced increased PA binding and uptake of the PA oligomer in vitro and in vivo through upregulation of the PA receptors TEM8 and CMG2 in both myeloid and nonmyeloid cells. ET effects on protein clearance from circulation appeared to be global and were not limited to PA. ET also impaired the clearance of ovalbumin, green fluorescent protein, and EF itself, as well as the small molecule biotin when these molecules were coinjected with the toxin. Effects on injected protein levels were not a result of general increase in protein concentrations due to fluid loss. Functional markers for liver and kidney were altered in response to ET. Concomitantly, ET caused phosphorylation and activation of the aquaporin-2 water channel present in the principal cells of the collecting ducts of the kidneys that are responsible for fluid homeostasis. Our data suggest that in vivo, ET alters circulatory protein and small molecule pharmacokinetics by an as-yet-undefined mechanism, thereby potentially allowing a prolonged circulation of anthrax virulence factors such as EF during infection.     

Incidence of Neonatal Hyperphenylalaninemia in Fars Province,South Iran

Objective

Phenylalanine hydroxylase or its cofactor, tetrahydrobiopterin (BH₄), deficiency causes accumulation of phenylalanine in body fluids and central nervous system. Considering the fact that hyperphenylalaninemia is a preventable cause of mental retardation in infants, the objective of this study was to determine the incidence of congenital hyperphenylalaninemia in Fars province, south of Iran.

Methods

In a period of one year from November 2007 to November 2008 blood samples were withdrawn from all newborns born in Fars province for measurement of serum phenylalanine. The samples with a serum level of≥ 2 mg/dl were referred to pediatric endocrine clinic for confirmation and determination of the type of hyperphenylalaninemia by quantitive serum phenylalanine measurements by using High-Pressure liquid chromatography (HPLC) method.

Findings

Nine out of 76966 newborns had a serum phenylalanine level≥2mg/dl, of which 8 cases were confirmed by HPLC. The incidence of the disease was 1:10000. The incidence of mild hyperphenylalaninemia and phenylketonuria (PKU) among the patients was 62.5% and 37.5% respectively and the incidence of BH₄ deficiency was 1/76966.

Conclusion

These findings indicate a high incidence of hyperphenylalaninemia, in the newborns from Fars province. The high incidence makes a comprehensive screening program for management of the disease necessary.     

Potent neutralization of anthrax edema toxin by a humanized monoclonal antibody that competes with calmodulin for edema factor binding

This study describes the isolation and characterization of a neutralizing monoclonal antibody (mAb) against anthrax edema factor, EF13D. EF13D neutralized edema toxin (ET)-mediated cyclic AMP (cAMP) responses in cells and protected mice from both ET-induced footpad edema and systemic ET-mediated lethality. The antibody epitope was mapped to domain IV of EF. The mAb was able to compete with calmodulin (CaM) for EF binding and displaced CaM from EF-CaM complexes. EF-mAb binding affinity (0.05–0.12 nM) was 50- to 130-fold higher than that reported for EF-CaM. This anti-EF neutralizing mAb could potentially be used alone or with an anti-PA mAb in the emergency prophylaxis and treatment of anthrax infection.Infection by inhalational anthrax is often fatal if treatment is delayed. Anthrax bacteria can be killed by vigorous treatment with antibiotics, but patients may still die because the lethality of anthrax is largely because of the action of toxins (1). Anti-toxin neutralizing monoclonal antibodies (mAbs) are the only viable choice for immediate neutralization of toxin and they could augment the effectiveness of antibiotics.Anthrax bacteria produce 3 toxin components: Protective antigen (PA), lethal factor (LF), and edema factor (EF) (2, 3). PA binds to cellular receptors and acts as a vehicle to deliver LF or EF into the cytosol where they exert their enzymatic activities (4–8). LF is a zinc-dependent protease that cleaves mitogen-activated protein kinase kinases and causes lysis of macrophages (9, 10). EF is a calcium-calmodulin (CaM)-dependent adenylate cyclase and causes local inflammation and edema (11). The combination of PA with LF results in lethal toxin (LT). LT can replicate symptoms of anthrax disease when injected into animals (12). PA together with EF forms edema toxin (ET) and ET can produce a range of toxic effects in the host (11, 13).PA has been regarded as the most important target for prophylaxis and therapy of anthrax, because PA is common to both LTs and ETs, initiates the toxic process via receptor binding, and is highly immunogenic. In fact, PA is the major component in the current anthrax vaccine and the target for most of the available human or human-like neutralizing mAbs that have been shown to be very effective in protection against anthrax toxin or spore challenge (14–19). However, there is evidence that LF and EF may play important roles in providing protective immunity (20–22). Furthermore, concerns that PA could potentially be manipulated, such that it would no longer be neutralized by current anti-PA neutralizing mAbs have led to interest in therapeutics against the other 2 toxin components. A mixture of mAbs that recognize distinct epitopes on multiple toxin components (PA, LF, or EF) would not only enhance the protective efficacy but also broaden the spectrum of protection. Thus, in recent years, several anti-LF mAbs have also been reported (23–27). However, no anti-EF neutralizing mAbs have been reported to date. A previous report had indicated that immunization with the PA-binding N-terminal domain of EF (amino acids 1–254) resulted in polyclonal sera containing both EF and LF neutralizing activities (28).The purpose of this study was to determine (i) if anti-EF neutralizing mAbs could be isolated; (ii) the effectiveness of such antibodies against anthrax ET effects; and (iii) the neutralization mechanism of these antibodies. We have made a Fab combinatorial phage display library from chimpanzees that were immunized with anthrax toxins (17). From the library, 4 EF-specific Fabs were recovered, and 1 of them had potent neutralizing activity independent of the homologous PA-binding N-terminal (1–254) domain of LF. In this report, we describe the detailed characterization of these anti-EF clones.     

Clinical use of liver biopsy for the diagnosis and management of inactive and asymptomatic hepatitis B virus carriers in Bangladesh

Patients with inactive chronic hepatitis B virus (HBV) infection are assumed to be free from liver disease. Accordingly, antiviral drug treatment is not recommended for these patients. However, the extent of liver damage in these patients has not been evaluated fully. The aim of this study was to evaluate the extent of liver damage in patients with inactive HBV. Liver biopsy was conducted in 141 inactive HBV carriers [HBeAg‐negative, low levels of HBV DNA (≤10,000 copies/ml) and normal levels of serum alanine aminotransferase (ALT)]. The extent of hepatic inflammation and fibrosis was evaluated in these patients by examining liver biopsy specimens. Although the patients were inactive HBV carriers, mild to moderate levels of necroinflammation (HAI necroinflammation score HAI‐N1 ≥ 7) were detected in 36 of 141 (26%) patients. Seventeen patients had a severe degree of hepatic fibrosis (HAI fibrosis score HAI‐F ≥ 3). A total of 10 patients had both considerable necroinflammation (HAI‐N1≥7) and severe fibrosis (HAI‐F ≥3). All 10 patients with significant hepatic inflammation and fibrosis were male and older than 25 years. However, all were HBeAg‐negative and expressed low levels of HBV DNA and normal ALT levels. The study demonstrates that features of liver damage were present in a considerable number of the patients. Assessment of liver biopsy specimens in a larger cohort of inactive HBV carriers is necessary to establish management guidelines for such patients. J. Med. Virol. 82:1350–1354, 2010. © 2010 Wiley‐Liss, Inc.     

Vascular dynamics in relation to immunolocalisation of VEGF-A, VEGFR-2 and Ang-2 in the bovine corpus luteum

Vascular dynamics during development and regression of the bovine corpus luteum were investigated morphometrically in relation to immunolocalisation of vascular endothelial growth factor A (VEGF-A), vascular endothelial growth factor receptor 2 (VEGFR-2) and angiopoietin 2 (Ang-2) in the different cell types. Angiogenesis and remodelling of the capillary network between day 8 and 17 of the oestrous cycle was driven by luteal cells, which were highly immunopositive for VEGF-A. Thereafter, immunoreactivity for VEGF-A and VEGFR-2 was mainly found in vascular smooth muscle cells, the predominant cell type in late luteolysis. During early regression, apoptosis of luteal and endothelial cells was closely correlated, resulting in a significant decrease of capillarity. In late regression, an increase in capillary density was found, suggesting that regression and transformation into the corpus albicans requires adequate perfusion. In the phases of vascular remodelling, i.e. mature and late regressing corpus luteum, high scores of Ang-2-immunopositive endothelial and smooth muscle cells were found. Therefore, it may be hypothesised that Ang-2 supports the angiogenic effects of VEGF-A in these luteal stages. Results emphasise that precise staging and a differentiated view on the cellular populations is important in evaluating the controlled regression and transformation of the corpus luteum.     

Head and neck paragangliomas: clinical and molecular genetic classification

Head and neck paragangliomas are tumors arising from specialized neural crest cells. Prominent locations are the carotid body along with the vagal, jugular, and tympanic glomus. Head and neck paragangliomas are slowly growing tumors, with some carotid body tumors being reported to exist for many years as a painless lateral mass on the neck. Symptoms depend on the specific locations. In contrast to paraganglial tumors of the adrenals, abdomen and thorax, head and neck paragangliomas seldom release catecholamines and are hence rarely vasoactive. Petrous bone, jugular, and tympanic head and neck paragangliomas may cause hearing loss. The internationally accepted clinical classifications for carotid body tumors are based on the Shamblin Class I-III stages, which correspond to postoperative permanent side effects. For petrous-bone paragangliomas in the head and neck, the Fisch classification is used. Regarding the molecular genetics, head and neck paragangliomas have been associated with nine susceptibility genes: NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, SDHAF2 (SDH5), and TMEM127. Hereditary HNPs are mostly caused by mutations of the SDHD gene, but SDHB and SDHC mutations are not uncommon in such patients. Head and neck paragangliomas are rarely associated with mutations of VHL, RET, or NF1. The research on SDHA, SDHAF2 and TMEM127 is ongoing. Multiple head and neck paragangliomas are common in patients with SDHD mutations, while malignant head and neck paraganglioma is mostly seen in patients with SDHB mutations. The treatment of choice is surgical resection. Good postoperative results can be expected in carotid body tumors of Shamblin Class I and II, whereas operations on other carotid body tumors and other head and neck paragangliomas frequently result in deficits of the cranial nerves adjacent to the tumors. Slow growth and the tendency of hereditary head and neck paragangliomas to be multifocal may justify less aggressive treatment strategies.     

Arsenic trioxide in patients with refractory multiple myeloma: a prospective, phase II, single-arm study

Multiple myeloma (MM) characterized by proliferation of plasma cells in bone marrow and production of monoclonal immunoglobulin's. Recently, arsenic trioxide (ATO), has been considered for treatment refractory MM. We assessed the safety and efficacy of ATO for patients with refractory MM. A phase 2, study of arsenic trioxide was conducted in 12 MM patients, whose refractory to two standard therapy. Patients received arsenic trioxide, 0.25 mg/kg/d for 5 d/week during the first 2 consecutive weeks of each 4-week cycle with 2 week rest. Patients who completed one 4-week cycle were evaluated for response to treatment. Twelve patients with refractory multiple myeloma received ATO. Disease assessment was based the amount of serum proteins electrophoresis. Of the10 patients; stable disease was observed in four patients(33%), progression disease in five patients (41.6%), complete response in one patient (3.8%) and the remaining two patients could not be assessed for a response (because of increased liver enzymes after the first week). Some adverse events: increase liver enzymes and serum creatinine, neutropenia, pruritus, nausea, vomiting, lower extremities edema, noninfectious diarrhea was observed. These results indicate that ATO is active and well tolerated as a single-agent salvage therapy, even in patients with late-stage, refractory MM.     

Hepatitis B among pregnant women attending health care facilities in rural Bangladesh

This study assessed hepatitis B prevalence among pregnant women attending health care facilities in rural Bangladesh. Blood samples were collected from 480 participants. HBsAg was positive in 0.4% of subjects, anti-HBc was positive in 21.5% and anti-HBs was positive in 8.5% of subjects. HBsAg was more prevalent among the older age group. Hepatitis B has a low prevalence among pregnant women in rural Bangladesh. Existing hepatitis B vaccination schedule in the Expanded Program on Immunization (EPI) to vaccinate the children in rural Bangladesh is appropriate.