Detection of opsonic antibodies against Enterococcus faecalis cell wall carbohydrates in immune globulin preparations

Three different commercially available polyvalent immune globulins (IG) were investigated for the existence of antibodies against cell wall carbohydrates of four different E. faecalis serotypes (using a cell wall carbohydrate-enzyme-linked immunosorbent assay), and whether these antibodies mediated opsonic killing (using an opsonic-killing assay). All three IG preparations contained antibodies against all four serotypes (CPS-A to CPS-D). However, only one of the three IG preparations showed opsonic killing against all four serotypes. Average killing was higher against serotypes A and B (72 and 79 %, respectively) than against serotypes C and D (30 and 37 %, respectively). Such IG preparations could play a role as an adjuvant therapeutic option in life-threatening infections with E. faecalis, particularly when resistant strains are involved.     

Reduction of angiocidin contributes to decreased HepG2 cell proliferation

Background

Angiocidin plays a key role in angiogenesis and tumor progression. High angiocidin expression is detected in some kind of solid tumors and tumor vascular endothelial cells. Several reports have shown the inhibition of angiogenesis and tumor growth caused by angiocidin. However, the role of angiocidin in liver cancers growth is still unclear.

Objectives

To examine angiocidin expression in SMMC-7221 and HepG2 cells and the role of angiocidin in liver cancer cell growth.

Methods

RT-PCR and western blot are used in this study to detect angiocidin expression. SiRNA and MTT experiments are used in exploring the role of angiocidin in tumor cell growth.

Results

Our study showed high angiocidin expression in two kinds of liver cancer cells. Angiocidin protein production in HepG2 cells were reduced significantly by siRNA. When HepG2 cells were transfected with siRNA-angiocidin, these cells showed very low proliferation activity compared with control cells. Our study suggests that reduction of angiocidin may contribute to decreased proliferation activity in liver cancer cells.

Conclusion

Angiocidin is highly expressed in liver cancer cells, and it may play a key role in tumor growth of liver cancers.     

Microvascular autoregulation in children and adolescents with type 1 diabetes mellitus

Aims/hypothesis

Deterioration of microvascular function may have an early onset in individuals with type 1 diabetes mellitus. We hypothesised that microvascular autoregulation is impaired in children with type 1 diabetes and can be detected non-invasively by postocclusive reactive hyperaemia (PORH).

Methods

Microvascular autoregulation was assessed in 58 children with type 1 diabetes and 58 age- and sex-matched healthy controls by PORH using laser Doppler fluxmetry. Baseline perfusion, biological zero (defined as a ‘no flow’ laser Doppler signal during suprasystolic occlusion), peak perfusion following occlusion, time to peak and recovery time (time until baseline perfusion is resumed) were recorded and compared between the groups.

Results

Peak perfusion was higher in children with type 1 diabetes than in healthy controls (1.7?±?0.93?AU [arbitrary units] vs 1.29?±?0.46?AU; p?=?0.004), and biological zero was lower in children with type 1 diabetes vs controls (0.14?±?0.04?AU vs 0.19?±?0.04?AU; p?Conclusions/interpretation PORH reveals impaired microvascular autoregulation in children with type 1 diabetes. The higher peak perfusion might reflect a decline in the vasoconstrictive ability of arteriolar smooth muscle cells upstream of capillary beds in children with type 1 diabetes.     

Self-assembly of tunable protein suprastructures from recombinant oleosin

Using recombinant amphiphilic proteins to self-assemble suprastructures would allow precise control over surfactant chemistry and the facile incorporation of biological functionality. We used cryo-TEM to confirm self-assembled structures from recombinantly produced mutants of the naturally occurring sunflower protein, oleosin. We studied the phase behavior of protein self-assembly as a function of solution ionic strength and protein hydrophilic fraction, observing nanometric fibers, sheets, and vesicles. Vesicle membrane thickness correlated with increasing hydrophilic fraction for a fixed hydrophobic domain length. The existence of a bilayer membrane was corroborated in giant vesicles through the localized encapsulation of hydrophobic Nile red and hydrophilic calcein. Circular dichroism revealed that changes in nanostructural morphology in this family of mutants was unrelated to changes in secondary structure. Ultimately, we envision the use of recombinant techniques to introduce novel functionality into these materials for biological applications.     

Medical complications of bariatric surgery: focus on malabsorption and dumping syndrome

Gastroenterologists increasingly see patients with symptoms after bariatric surgery. A number of gastrointestinal or extra-gastrointestinal symptoms should raise the suspicion of malabsorption or dumping syndrome. Little is known about long-term consequences of disordered intestinal anatomy and physiology resulting from bariatric surgical procedures. The latency phase of clinical problems is unknown, but may potentially be long, and postoperative courses over many decades have to be considered regarding the consequences of surgical alterations of gastrointestinal structure and function. Long-term nutritional requirements in patients with bariatric procedures are incompletely understood. This review focuses on the pathophysiology of long-limb Roux-en-Y gastric bypass (RYGB) because it has become the most common bariatric procedure in many parts of the world. Although several potential mechanisms for nutritional deficiencies after RYGB like deficiency of dietary intake, lack of gastric secretions, exclusion of proximal duodenum and jejunum, or asynergia between food bolus and biliopancreatic secretions have been postulated, it was only very recently that in-depth studies have been carried out to measure the extent to which the long-limb RYGB causes malabsorption. In order to improve care for these patients, specialists who are trained in understanding pathophysiological changes in digestion and absorption after bariatric surgery and who recognize and treat clinical symptoms and nutritional deficits after bariatric surgery are needed. In addition, clinical researchers should take advantage of the experimental setups provided by standardized surgical procedures, and scientific societies should design courses and scientific meetings which combine the expertise in gastroenterology, surgery and nutrition.     

Human Immunodeficiency Virus nef signature sequences are associated with pulmonary hypertension

Severe pulmonary hypertension (PH) associated with vascular remodeling is a long-term complication of HIV infection (HIV-PH) affecting 1/200 infected individuals vs. 1/200,000 frequency in the uninfected population. Factors accounting for increased PH susceptibility in HIV-infected individuals are unknown. Rhesus macaques infected with chimeric SHIVnef virions but not with SIV display PH-like pulmonary vascular remodeling suggesting that HIV-Nef is associated with PH; these monkeys showed changes in nef sequences that correlated with pathogenesis after passage in vivo. We further examined whether HIV-nef alleles in HIV-PH subjects have signature sequences associated with the disease phenotype. We evaluated specimens from participants with and without HIV-PH from European Registries and validated results with samples collected as part of the Lung-HIV Studies in San Francisco. We found that 10 polymorphisms in nef were overrepresented in blood cells or lung tissue specimens from European HIV-PH individuals but significantly less frequent in HIV-infected individuals without PH. These polymorphisms mapped to known functional domains in Nef. In the validation cohort, 7/10 polymorphisms in the HIV-nef gene were confirmed; these polymorphisms arose independently from viral load, CD4(+) T cell counts, length of infection, and antiretroviral therapy status. Two out of 10 polymorphisms were previously reported in macaques with PH-like pulmonary vascular remodeling. Cloned recombinant Nef proteins from clinical samples down-regulated CD4, suggesting that these primary isolates are functional. This study offers new insights into the association between Nef polymorphisms in functional domains and the HIV-PH phenotype. The utility of these polymorphisms as predictors of PH should be examined in a larger population.     

Presentation of Primary Open Angle Glaucoma (POAG) at Lions Sight First Eye Hospital in Blantyre,Malawi

Objective

Primary open angle glaucoma (POAG) is the most common type of glaucoma in Africa. We carried out a study to determine the clinical presentation pattern of patients with primary open angle glaucoma (POAG) at a tertiary hospital in Malawi.

Design

A cross-sectional study

Setting

Lions Sight First Eye Hospital—a major referral and teaching state eye hospital in Blantyre, Malawi

Subjects

Study participants were newly diagnosed POAG patients at specialist eye clinic during study period.

Results

A total of 60 POAG patients were recruited into the study. The mean age was 58.7 years (SD= 16.6, range 18 - 86). There were more male (44, 73.3%) than female (16, 27.7%) patients. The majority of patients (73%) presented one year after onset of visual symptoms. Twenty-six patients (43%) had unilateral blindness (visual acuity < 3/60; WHO classification), while nine patients (15%) presented with bilateral blindness. A vertical cup-to-disc ratio (CDR) of 0.8 or worse was seen in 92 eyes (79%). The mean intraocular pressure (IOP) reading was 35.5 mmHg (SD 13.30). Of the thirty-three eyes that successfully underwent visual field analysis, very advanced defects were recorded in 12 eyes (36%).

Conclusion

This study demonstrates delayed presentation and male predominance among POAG patients at a tertiary eye hospital in Malawi. Glaucoma intervention programmes should aim at identifying patients with treatable glaucoma with particular attention to women.