Attenuation of eNOS expression in cadmium-induced hypertensive rats

Cadmium (Cd) has been reported to induce hypertension in both humans and animals; however, its mechanism has not been clearly elucidated. Vascular tone is one of the factors contributing to hypertension. This study was conducted to investigate the effects of Cd exposure on vascular muscarinic receptor responses to acetylcholine (ACh) in isolated aortas. Male Sprague-Dawley rats were exposed to Cd via drinking water (5, 10 and 50 ppm) for 3 months. Cd 10 and 50 ppm exposure caused significant decreases in the sensitivity of vascular muscarinic receptors to ACh. However, Cd exposure did not alter the vascular relaxation induced by sodium nitroprusside (SNP) which is a nitric oxide donor. Consistent with the reduction of ACh-induced relaxation, treatment with Cd decreased endothelial nitric oxide synthase (eNOS) protein level in blood vessels. These results suggested that Cd suppressed ACh-induced vascular relaxation by interfering with muscarinic receptor function, and its downstream signaling pathway may be one of the contributing factors for the development of hypertension.     

Infliximab stopped severe gastrointestinal bleeding in Crohn's disease

To report the result of rapid ulcer healing by infliximab in Crohn's patients with severe enterocolic bleeding. During 2005 and 2010, inflammatory bowel disease database of King Chulalongkorn Memorial and Samitivej hospitals were reviewed. There were seven Crohn's disease (CD) patients (4 women and 3 men; mean age 52 ± 10.4 years; range: 11-86 years). Two of the seven patients developed severe gastrointestinal bleeding (GIB) as a flare up of CD whereas the other five patients presented with GIB as their first symptom for CD. Their mean hemoglobin level dropped from 12 ± 1.3 g/dL to 8.7 ± 1.3 g/dL in a 3-d period. Median packed red blood cells units needed for resuscitation was 4 units. Because of uncontrolled bleeding, surgical resection was considered. However, due to the poor surgical candidacy of these patients (n = 3) and /or possible development of short bowel syndrome (n = 6), surgery was not pursued. Likewise angiographic embolization was not considered in any due to the risk of large infarction. All severe GIBs successfully stopped by one or two doses of intravenous infliximab. Our data suggests that infliximab is an alternative therapy for CD with severe GIB when surgery has limitation or patient is a high risk.     

Successful peripheral blood stem cell mobilization using pegfilgrastim in allogeneic stem cell transplantation

Pegfilgrastim is produced by binding a 20,000-dalton polyethylene glycol molecule to granulocyte colony-stimulating factor (G-CSF), increasing the mass of the compound, and resulting in a longer-lasting form of G-CSF. This makes it more convenient to use pegfilgrastim as a single-day injection. This study was a prospective phase II single-center trial. Fifteen normal related donors received pegfilgrastim 12 mg subcutaneously to mobilize peripheral blood stem cells (PBSC) for allogeneic stem cell transplantation. Leukapheresis was planned to start 3 days after injection. All harvests were successful. Median number of leukapheresis was 2 days (range 1–3 days). There were 7/15 donors who only required single leukapheresis. The maximum concentration of white blood cells (WBC) and circulating CD34 cells occurred 3 days after pegfilgrastim injection (WBC: median 62,200/μl; CD34: median 69.76/μl). The median yield of CD34 cells was 6.78 × 10⁶/kg recipient weight. The median CD3 cells was 1.89 × 10⁸/kg recipient weight. The main adverse events were bone pain and headache. Median neutrophil and platelet engraftments in the recipients occurred on day 12 and day 13, respectively, after transplantation. PBSC mobilization with single-day injection of pegfilgrastim in normal donor is feasible. Further comparisons of this protocol to standard G-CSF for allogeneic stem cell mobilization should be conducted in future.     

Stent-in-stent through a side hole to prevent biliary metallicstent migration

The covered self-expandable metallic stent(SEMS) has been developed to overcome the problem of tissue ingrowth,However,stent migration is a well-known complication of covered SEMS placement.Use of a double pigtail stent to lock the movement of the SEMS and prevent migration has been advised by many experts.Unfortunately,in our case this technique led to an incidental upward migration of the SEMS.We used APC to create a side hole in the SEMS for plastic stent insertion as stent-in-stent.This led to a successful prevention of stent migration.     

Antibody elutions in Thai patients with a positive direct antiglobulin test

Background

The direct antiglobulin test is performed to determine whether an anaemic patient with evidence of haemolysis has autoimmune or alloimmune haemolytic anaemia.

Materials and methods

We determined the antibody specificity of eluted IgG antibodies from patients’ blood samples with a positive direct antiglobulin test. Overall, 134 Thai patients were included in this study. EDTA blood samples were obtained from recently transfused patients, patients with unexplained anaemia and patients who had serum antibodies detected during routine pre-transfusion tests from different hospital blood banks. These complicated samples were sent to the National Blood Centre of the Thai Red Cross Society for investigation and to find compatible blood components. Each blood sample underwent a direct antiglobulin test with the gel technique using polyspecific antihuman globulin and mononospecific anti-IgG and anti-C3d. Acid eluates were prepared from the samples for which the direct antiglobulin test was positive and the specificities of the eluted antibodies were determined by the gel technique.

Results

Of the samples tested, 101 showed a positive direct antiglobulin test result (75.4%) using polyspecific antihuman globulin sera whereas only 95 samples (70.9%) were positive with anti-IgG or anti-IgG and anti-C3d. Moreover, 54 of 95 eluates (56.8%) were positive for antibody screening and tested with the reagent panel cells. Twenty-one eluates had specific alloantibodies, which were concordant with the findings in the patients’ sera and all patients had a history of blood transfusion. Additionally, 33 eluates contained pan-agglutinins. Interestingly, alloantibodies could be determined using titration studies in 5 of 26 eluates with pan-agglutinins.

Conclusion

Although the direct antiglobulin test is not routinely performed in pre-transfusion screening, this test and elution studies would be useful in patients with a history of previous transfusions, and in those for whom compatible blood cannot be found.     

Role of digital chromoendoscopy in detecting minimal change esophageal reflux disease

Endoscopy is a widely used diagnostic tool to detect reflux esophagitis. Although its specificity was reported to be excellent at 90%-95%, its sensitivity was only 50%. Therefore, it is quite difficult to detect these lesions under the standard white light endoscopy especially in patients with minimal change esophageal reflux disease (MERD). In recent years, endoscopic technologies have evolved tremendously; these include high resolution and magnification digital chromoendoscopy. These technologies are useful practically for detecting various subtle lesions along the gastrointestinal tract starting from esophagus to colon. Currently, these technologies can be classified in 2 systems; pre-processed system (NBI, Olympus) and post processed system (FICE and i-SCAN, Fujinon and Pentax respectively). Over a few years, there have been many emerging publications on the benefit of these systems on MERD detection. The overall sensitivities to diagnose MERD were reported as much better than controls. However, large, multi-center and randomized controlled studies comparing these new imaging modalities with the conventional white light chromoendoscopy are warranted to validate its accuracy. Standard, simple and precise endoscopic reading criteria for the identification of MERD are also required.