Replacing Acid-Heat Precipitation with Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis Improves Detecting Bence-Jones proteinuria

Background: detecting Bence-Jones protein in urine is essential for determining plasma cell dyscrasia and multiple myeloma. Conventionally, acid-heat precipitation assay is used for detecting Bence-jones protein in most medical laboratories; however, because of the low accuracy of this test, other more sensitive tests like urine electrophoresis are recommended

Materials and Methods: in this study, the presence of Bence-jones protein in the urine of patients suspected to monoclonal gammopathies were compared using acid-heat precipitation, capillary immunoelectrophoresis and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Moreover, the subsets of light chain [kappa and lamda] in capillary immunoelectrophoresis were determined

Results: our data showed high false negative results [77.7%] using acid-heat precipitation assay in comparison with polyacrylamide gel and capillary immunoelectrophoresis [0%]

Conclusion: collectively, in spite of advantages like easy performance and low cost, acid-heat precipitation assay is not reliable for determining Bence-jones proteinuria in medical laboratories due to its low sensitivity. Therefore, it is recommended to be replaced with more sensitive assays like electrophoresis

Guinea Pig as an appropriate model for colonization of helicobacter pylori

Animal models have been proven useful in elucidating the details of interaction between pathogenic bacteria and their human hosts, in addition to assessing the efficacy of therapeutic compounds and vaccines. In this study, we investigate the colonization of Helicobacter pylori [H. pylori] in experimentally-infected guinea pigs over a six-month period. A bacterial suspension was prepared by mixing four H. pylori isolates obtained from patients diagnosed with gastric ulcer. Within a one week period, five female guinea pigs were dosed orally with bacterial suspension for a total of three times. One control animal was gavaged with normal saline. Stool samples were collected at two-week intervals for six months. We used PCR, the stool antigen test, and indirect immunofluorescence assay [IFA] to assess samples for the presence of H, pylori. Stomachs obtained from two chloroform-killed animals, at 8 and 24 weeks, were investigated for histopathologic changes. H. pylori 16S rDNA was amplified from the stool samples of five guinea pigs. The stool antigen test was also positive in all five animals. IFA demonstrated the presence of H, pylori antigens in the stools from all five animals. PCR, stool antigen test and IFA results showed no H. pylori in the stool of the control animal. We observed infiltration of mature lymphocytes and plasma cells in the stomachs of animals killed at 8 and 24 weeks. The occurrence of H, pylori 16S rDNA and antigens in stool samples of guinea pigs demonstrated persistent colonization off H, pylori in the stomachs of guinea pigs. Histopathological findings have confirmed mild-severe gastritis induced by the bacterial infection. The stomach of a guinea pig is similar to the human stomach, in that it is sterile, lined by glandular epithelium, lacks a vitamin C synthesizing system and produces the cytokine interleukin-8. Accordingly, the guinea pig can be considered an appropriate animal model for long-term experiments to follow the process of H, pylori pathogenesis or to assess the efficacy of antibiotics or vaccines

[Phenotyping of peripheral memory T cell subsets in cutaneous leishmaniasis]

The heterogenous population of memory T lymphocytes is distinguished based on surface markers and effector functions such as cytokine secretion. Recently, two subsets of memory T cells are defined by expression of chemokine receptor CCR7 and CD45RA designating as "central memory" T cells [TCM] and "effector memory" T cells [TEM]. The objective of this study was to evaluate the phenotype and function of these lymphocytes in healed cases of cutaneous leishmaniasis. The phenotype of lymphocytes were determined in blood samples of 13 volunteers with history of self healing cutaneous leishmaniasis [HCL] and in 6 healthy controls. No significant difference was found in memory T cell subsets between HCL volunteers and healthy controls using flow cytometry. However, following sorting of different memory subsets, a significantly higher proliferation was seen in cells of HCL volunteers comparing to the control group. A significantly higher IFN-gamma response in TEM and a significantly higher IL-2 response in TCM were observed in cell culture of HCL volunteers comparing controls. The responses were elicited when the cells were stimulate with SLA in vitro, it is concluded Leishunania-specific TEM and Leishmania-specific TEM subsets exist in HCL volunteers and since the volunteers with history of CL presumed to be protected against reinfection, it seems that both TCM and TEM play role in the protection against Leishmania infection in these individuals

Dendritic cells bearing HLA-G inhibit T-cell activation in type 1 diabetes

HLA-G is normally expressed on human trophoblast cells. It is a non-classical MHC molecule class I b. The role of HLA-G in diabetic type 1 is not known. We investigated the role of IFN-beta in induction HLA-G expression on the monocyte derived dendritic cells [DC] in diabetes type 1. Treatment of dendritic cell with IFN-beta in vitro from diabetic patients [n=20] and normal subjects [n=20] resulted to the production and expression of HLA-G on these cells from both groups. However, comparison of DC from the diabetic patients with DC from the controls revealed lower levels of HLA-G molecules in DC from diabetic patients. Using mixed lymphocyte reaction [MLR], it was found that DC expressing HLA-G mediated the inhibition of autologous T cell activation. It is concluded that IFN-beta can increase HLA-G in DC from diabetic patients; subsequently it may prevent the immune regularly pathway in the diabetic pathogenesis

Urinary Tamm-Horsfall protein and citrate: a case-control study of inhibitors and promoters of calcium stone formation

This study aimed to compare urinary Tamm-Horsfall protein [THP], citrate, and other inhibitors and promoters of stone formation in calcium stone formers with those in healthy individuals. From January 2002 to June 2004, 100 calcium stone formers [mean age, 38.6 +/- 10.3 years] who had at least 2 episodes of calcium stone formation were compared with 100 healthy individuals [mean age, 33.8 +/- 9.7 years]. Their 24-hour urine THP [using the sodium dodecyl sulfate polyacrylamide gel electrophoresis method], citrate, calcium, uric acid, oxalate, and magnesium values were measured and compared. The mean 24-hour urine THP was 3.3 +/- 8.1 mg in patients in the study group and 4.6 +/- 19.2 mg in controls [P=0.5]. However, THP in individuals with and without bacteriuria was significantly different [15.8 +/- 33.6 versus 2.6 +/- 10.2, P<0.001]. Mean 24-hour urinary calcium, citrate, and oxalate values were 232.6 +/- 95.3 mg and 177.8 +/- 82.7 mg [P<0.001], 132 +/- 103.2 mg and 395 +/- 258.5 mg [P<0.001], and 18.9 +/- 22.5 mg and 10.4 +/- 8.5 mg [P<0.001] in patients in the study and control groups, respectively. There was a significant positive correlation between urinary citrate and promoters of stone formation, including urinary calcium, oxalate, and uric acid, in patients in the control group, but not in patients in the study group. THP in the urine of stone formers is not quantitatively different from that of healthy individuals, but it is different in patients with bacteriuria. Increased urinary excretion of calcium, oxalate, and uric acid in stone formers with no increase in urine citrate may play a role in the pathogenesis of recurrent stone formation

Over expression of Wilm's tumor gene 1[WT1] in Iranian patients with acute myeloblastic leukemia

The Wilm's tumor gene 1 [WT1] encodes a zinc finger transcription factor that is inactivated in a subset of Wilm's tumors. It plays a crucial role in growth, proliferation and development of some embryonic and adult organs. WT1 is expressed as a tumor associated antigen [TAA] in various types of solid and hematopoietic malignancies and can be employed as a useful marker for targeted immunotherapy and monitoring of minimal residual disease [MRD]. To investigate the profile of WT1 gene expression in Iranian patients with acute myeloblastic leukemia. RT-PCR method was used to determine the WT1 gene expression in bone marrow [BM] and/or peripheral blood [PB] samples from 11 patients with AML and PB samples of 36 normal subjects. Isolated cells from all patients were immunophenotyped by flow cytometry. The leukemic cells from 10 patients [91%] were found moderately or strongly positive for WT1 expression whereas only 3 out of 36 normal subjects expressed WT1 at very low levels. A highly significant correlation was observed for WT1 expression between paired BM and PB samples of the AML patients. Our results indicate that WT1 is expressed in the majority of Iranian AML patients and may be employed for screening and monitoring of minimal residual disease in these patients

effect of antibiotics on LPS release from salmonella typhi and its relation to TNF-a production by human whole blood, EX-VIVO

It seems that rapid destruction of gram negative bacteria by antibiotics contributes to the clinical deterioration of some patients with gram negative infections. Antibiotics increase the concentration of lipopolysaccharide [LPS] in blood and cerebrospinal fluids. Released LPS can activate blood cells to produce tumor necrosis factor-alpha [TNF-alpha] and other cytokines. TNF-[alpha] appears to be a major mediator in development of fever, hypotension, multi-organ failure and death. In this research, standard Salmonella typhi Ty[2] -5536, a pathogenic Salmonella and standard Escherichia coli K12,QD5003 for comparing, were incubated in the presence of chloramphenicol, ampicillin and co-trimoxazole at concentrations that killed >99.9% of organisms as determined by quantitative culture techniques. The results obtained showed that chloramphenicol produced lower LPS levels and lower TNF-[alpha] levels from whole blood cells when compared with those of ampicillin and co-trimoxazole. Therefore chloramphenicol is the preferred antibiotic against S. typhi because it decreases the induced-pathological effect of TNF-[alpha] in gram negative infections