IL4R and IL13 polymorphic variants and development of antibodies to surface antigen of hepatitis B virus in hemodialysis patients in response to HBV vaccination or infection

We searched for an association between the interleukin 4 receptor gene (IL4R) rs1805015 and interleukin 13 gene (IL13) rs20541 polymorphisms and the development of antibodies to hepatitis B surface antigen (anti-HBs) in the case of hepatitis B virus (HBV) vaccination or infection in hemodialysis (HD) patients. HD patients who failed to respond to HBV vaccination did not differ in genotype frequencies of IL4R (TT 72.7%, CT 22.6%, CC 4.7%) and IL13 (CC 59.0%, CT 34.2%, TT 6.8%) from vaccine responders (IL4R TT 68.0%, CT 27.3%, CC 4.7%; IL13 CC 55.0%, CT 38.5%, TT 6.5%). HD patients who did not develop anti-HBs despite HBV infection also did not differ in genotype frequencies of IL4R (TT 67.8%, CT 26.8%, CC 5.4%) and IL13 (CC 60.7%, CT 33.9%, TT 5.4%) from HD patients who developed an anti-HBs response (IL4R TT 65.4%, CT 30.8%, CC 3.8%; IL13 CC 60.5%, CT 34.6%, TT 4.9%). In HD patients, neither the IL4R nor IL13 polymorphism is associated with anti-HBs development irrespective of whether an immunization is provoked by HBV vaccination or HBV infection.     

Laparoscopic Heller's myotomy for achalasia after gastric bypass: A case report

INTRODUCTIONDisorders of the oesophagus have been linked to surgical bariatric procedures and obesity. However the relationship between achalasia and gastric bypass is not clearly understood and has only recently been reported following gastric bypass.PRESENTATION OF CASEWe present the case of a 53-year-old woman who re-presented following a gastric bypass with a new diagnosis of achalasia. This was treated successfully with laparoscopic Heller's Myotomy with discharge from hospital 10 days post operatively.DISCUSSIONIt is not clear whether achalasia is a complication of gastric bypass procedures. This is only the second reported case of the condition developing after this operation. The mechanism by which it may develop is yet to be clearly established.CONCLUSIONThis case highlights the need to investigate further a possible link between achalasia and gastric bypass and to manage susceptible patients accordingly in the pre-operative stage.     

Toxigenic effects of diatoms on grazers, phytoplankton and other microbes: a review

Traditionally, diatoms have been regarded as providing the bulk of the food that sustains the marine food chain and important fisheries. However, this view was challenged almost two decades ago on the basis of laboratory and field studies showing that when copepods, the principal predators of diatoms, feed on certain diatom diets, they produce abnormal eggs that either fail to develop to hatching or hatch into malformed (i.e. teratogenic) nauplii that die soon afterwards. Over the years, many explanations have been advanced to explain the causes for reproductive failure in copepods and other marine and freshwater invertebrates including diatom toxicity, or nutritional deficiency and poor assimilation of essential compounds in the animal gut. Here we review the literature concerning the first possibility, that diatoms produce cytotoxic compounds responsible for growth inhibition and teratogenic activity, potentially sabotaging future generations of grazers by inducing poor recruitment. The cytotoxic compounds responsible for these effects are short chain polyunsaturated aldehydes (PUAs) and other oxygenated fatty acid degradation products such as hydroxides, oxo-acids, and epoxyalcohols (collectively termed oxylipins) that are cleaved from fatty acid precursors by enzymes activated within seconds after crushing of cells. Such toxins are suggested to have multiple simultaneous functions in that they not only deter herbivore feeding but some also act as allelopathic agents against other phytoplankton cells, thereby affecting the growth of competitors, and also signalling population-level cell death and termination of blooms, with possible consequences for food web structure and community composition. Some oxylipins also play a role in driving marine bacterial community diversity, with neutral, positive or negative interactions depending on the species, thereby shaping the structure of bacterial communities during diatom blooms. Several reviews have already been published on diatom-grazer interactions so this paper does not attempt to provide a comprehensive overview, but rather to consider some of the more recent findings in this field. We also consider the role of diatom oxylipins in mediating physiological and ecological processes in the plankton and the multiple simultaneous functions of these secondary metabolites.     

Frameshift mutation in p53 regulator RPL26 is associated with multiple physical abnormalities and a specific pre-ribosomal RNA processing defect in diamond-blackfan anemia

Diamond-Blackfan anemia (DBA) is an inherited form of pure red cell aplasia that usually presents in infancy or early childhood and is associated with congenital malformations in ～30-50% of patients. DBA has been associated with mutations in nine ribosomal protein (RP) genes in about 53% of patients. We completed a large-scale screen of 79 RP genes by sequencing 16 RP genes (RPL3, RPL7, RPL8, RPL10, RPL14, RPL17, RPL19, RPL23A, RPL26, RPL27, RPL35, RPL36A, RPL39, RPS4X, RPS4Y1, and RPS21) in 96 DBA probands. We identified a de novo two-nucleotide deletion in RPL26 in one proband associated with multiple severe physical abnormalities. This mutation gives rise to a remarkable ribosome biogenesis defect that affects maturation of both the small and the large subunits. We also found a deletion in RPL19 and missense mutations in RPL3 and RPL23A, which may be variants of unknown significance. Together with RPL5, RPL11, and RPS7, RPL26 is the fourth RP regulating p53 activity that is linked to DBA.