Assessment of aldehyde dehydrogenase in viable cells

Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations.     

Accuracy of supplementary serologic testing for human T-lymphotropic virus types I and II in US blood donors. Retrovirus Epidemiology Donor Study

Blood donations in the United States have been screened for antibody to human T-lymphotropic virus type I (HTLV-I) by HTLV-I enzyme immunoassay (EIA) since November 1988. Specimens repeatedly found to be reactive by EIA undergo confirmation by supplementary serologic tests. We assessed the accuracy of blood center testing of 994 HTLV-I EIA repeat-reactive specimens in five US blood centers between November 1988 and December 1991. Of 410 confirmed HTLV-I/II donations, 407 (99.3%) were infected with HTLV-I/II, as determined by polymerase chain reaction (PCR) (403 cases) and by repeat serologic testing (4 cases). The three false- positive results occurred in the first year of testing. Of 425 HTLV- indeterminate specimens, 6 (1.4%) were found to be infected by PCR (5 with HTLV-II and 1 with HTLV-I). None of 159 confirmatory test-negative donations was PCR positive. Of HTLV-I/II-seropositive specimens, 80.2% to 95.4% could be typed as HTLV-I or HTLV-II by type-specific serologic assays. These results support recommendations that HTLV-I/II- seropositive donors should be advised that they are infected with HTLV- I, HTLV-II, or HTLV-I/II (depending on results of type-specific assays). HTLV-indeterminate donors should be advised that their results only rarely indicate HTLV infection. HTLV confirmatory test-negative donors should be reassured that they are not infected with HTLV-I or HTLV-II.     

Methicillin-resistant Staphylococcus aureus in hospitals and the community: stealth dynamics and control catastrophes

Methicillin-resistant Staphylococcus aureus (MRSA) represents a serious threat to the health of hospitalized patients. Attempts to reduce the spread of MRSA have largely depended on hospital hygiene and patient isolation. These measures have met with mixed success: although some countries have almost eliminated MRSA or remained largely free of the organism, others have seen substantial increases despite rigorous control policies. We use a mathematical model to show how these increases can be explained by considering both hospital and community reservoirs of MRSA colonization. We show how the timing of the intervention, the level of resource provision, and chance combine to determine whether control measures succeed or fail. We find that even control measures able to repeatedly prevent sustained outbreaks in the short-term can result in long-term control failure resulting from gradual increases in the community reservoir. If resources do not scale with MRSA prevalence, isolation policies can fail "catastrophically."     

Etiologic and Epidemiologic Pattern of Urolithiasis in North Iran;Review of 10-Year Findings

Objective: To determine epidemiologic and metabolic characteristics of renal stone in the northern Iran. Methods: We prospectively analyzed demographic, clinical and metabolic findings in children less than 16 years old with renal stone revealed by ultrasonography from September 2003 to May 2012. Evaluations included serum and urine measurement of main elements predisposing patients to stone formation. Findings : 271 children (160 males) aged 2 months to 16-years (mean 30 months) were evaluated. 91 (33.6%) had a positive family history, abdominal discomfort (18.8%), UTI (11.8%) and hematuria (11.4%) were main presenting features. 45 children were diagnosed accidentally without any specific compliant. Nearly all (99%) stones lay in kidney., 35.1% had metabolic, 10% infective and 4.1% obstructive trends, 110 children had no definable etiology. Hypercalciuria (25.5%) hyperoxaluria (18.4%) and hypocitraturia (18.1%) were more frequent than uricosuria (8.5%) and cystinuria (3.1%) Conclusion: Metabolic derangement plays significant role in stone formation in our area. Patients should be carefully evaluated considering this point of view.Key Words: Nephrolithiasis, Kidney Stone, Hypercalciuria, Hyperoxaluria, Cystinuria, Hypocitraturia     

Low Postprandial Circulating Inactive Ghrelin: Role of Early Satiety in Undernourished Children

Objective

To determine difference in the levels of circulating inactive ghrelin between undernourished and healthy children.

Methods

The present cross-sectional study was conducted in undernourished children from southwestern Iran, from July 2011 through July 2012. Postprandial inactive ghrelin levels were measured in 40 undernourished children and sex- and age-matched healthy controls by enzyme immunoassay.

Results

The levels of postprandial inactive ghrelin were considerably lower in undernourished compared to the healthy children (6.4 vs. 12.9, P?vs. 7.1, P?=?0.032).

Conclusions

Thus, the levels of inactive ghrelin was found to be low in undernourished children compared to healthy children. Early loss of appetite might be a result of low circulating inactive ghrelin levels in the postprandial state in undernourished children.     

Non-Viral Related Liver Enzymes Elevation After Kidney Transplantation

Background:

Liver enzymes elevations (LEE) can be observed after kidney transplantation due to multifactorial causes.

Objectives:

We performed a retrospective study on 1589 kidney transplants, 971 male and 618 female, who were hepatitis B surface antigen (HBsAg) and hepatitis C virus-antibody (HCV Ab) negative, and had no other liver diseases, to detect the prevalence of LEE and its risk factors in these patients between May 2008 and May 2010.

Patients and methods:

Liver enzymes and other biochemical parameters were measured in all recipients. Patients were divided into three groups, according to laboratory test time since transplantation: Group I, less than 3 months, Group II, 4 - 12 months after transplantation, and Group III, more than one year post-transplantation.

Results:

The highest LEE was more frequent in older patients (P < 0.001) and male individuals (P < 0.001). Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were higher in patients who received kidneys from deceased donors (10.4% and 23.8%, respectively) as compared to living donor transplants (5.6% and 14.8%, respectively) (P < 0.001). The elevation of ALT was the liver enzyme abnormality after kidney transplantation with the highest prevalence (34.3%). The levels of ALT and AST were significantly elevated within the first 3 months after transplantation, followed by the 4-12 months period (P < 0.001). There was a reverse correlation between liver enzyme levels and renal allograft function in both univariate and linear regression analyses. This correlation increased over time. There was also a significant relation between cyclosporine blood levels and liver enzyme values in the univariate analysis. However, this relationship was attenuated over time. Elevated liver enzymes also correlated with anemia.

Conclusions:

The LEE is a common finding among kidney transplant recipients. Serial monitoring of aminotransferases, particularly ALT, should be performed in all patients after kidney transplantation.     

Do women exhibit greater differences in established and novel risk factors between diabetes and non-diabetes than men? The British Regional Heart Study and British Women’s Heart Health Study

Aims/hypothesis  

Type 2 diabetes is associated with greater relative risk of CHD in women than in men, which is not fully explained by conventional cardiovascular risk factors. We assessed whether cardiovascular risk factors including more novel factors such as markers of insulin resistance, inflammation, activated coagulation and endothelial dysfunction differ more between diabetic and non-diabetic women than between diabetic and non-diabetic men, and the role of insulin resistance.     

Discovery of an orally active small-molecule irreversible inhibitor of protein disulfide isomerase for ovarian cancer treatment

Protein disulfide isomerase (PDI), an endoplasmic reticulum chaperone protein, catalyzes disulfide bond breakage, formation, and rearrangement. The effect of PDI inhibition on ovarian cancer progression is not yet clear, and there is a need for potent, selective, and safe small-molecule inhibitors of PDI. Here, we report a class of propynoic acid carbamoyl methyl amides (PACMAs) that are active against a panel of human ovarian cancer cell lines. Using fluorescent derivatives, 2D gel electrophoresis, and MS, we established that PACMA 31, one of the most active analogs, acts as an irreversible small-molecule inhibitor of PDI, forming a covalent bond with the active site cysteines of PDI. We also showed that PDI activity is essential for the survival and proliferation of human ovarian cancer cells. In vivo, PACMA 31 showed tumor targeting ability and significantly suppressed ovarian tumor growth without causing toxicity to normal tissues. These irreversible small-molecule PDI inhibitors represent an important approach for the development of targeted anticancer agents for ovarian cancer therapy, and they can also serve as useful probes for investigating the biology of PDI-implicated pathways.     

Prevalence and antimicrobial resistance of Salmonella isolated from fish, shrimp, lobster, and crab in Iran

The objective of this study was to determine the Salmonella prevalence, the serotypes involved, and antimicrobial susceptibility patterns of Salmonella isolates recovered from fish, shrimp, lobster, and crab in Iran. A total of 384 samples of fish, shrimp, lobster, and crab were collected in three provinces along the Persian Gulf in the south coast of Iran. Samples were collected at the end of each month from September 2009 to May 2011. All samples were evaluated for the presence of Salmonella, stereotyped and tested for antimicrobial susceptibility. There was an overall Salmonella prevalence of 5%. Salmonella was isolated from a significantly larger number of fish (10.4%) than shrimp (1.8%; P?≤?0.05). No Salmonella was isolated from lobster and crab samples. Salmonella isolates recovered from fish and shrimp samples were of five different serotypes including Salmonella typhimurium, Salmonella enteritidis, Salmonel la typhi, Salmonella paratyphi B, and Salmonella newport. Susceptibilities of Salmonella isolates were determined for 12 antimicrobial drugs using the disk-diffusion method. Resistance to nalidixic acid was the most common finding (47.4%), followed by resistance to tetracycline (36.8%), streptomycin (15.8%), trimethoprim (15.8%), and ciprofloxacin (5.3%). To our best knowledge, this is the first study on prevalence of Salmonella in fish, shrimp, lobster, and crab and the first report on the isolation of Salmonella spp. from retail fish and shrimp in Iran.