Monoclonal antibody to the gastrin receptor on parietal cells recognizes a 78-kDa protein.

Four monoclonal antibodies reactive by immunofluorescence and by flow microfluorimetry with canine and porcine gastric parietal cell membranes were produced by fusion of mouse NS-1 myeloma cells with splenocytes from mice immunized with a population of canine gastric mucosal cells containing 60-70% parietal cells. One of these, an IgM antibody designated 2C1, reacted with the surface membranes of parietal cells by immunofluorescence, flow microfluorimetry, and immunogold electron microscopy; competed with 125I-labeled gastrin for binding to gastric cells; and inhibited by 56% maximal gastrin stimulation of [14C]aminopyrine uptake in parietal cells. The antibody immunoprecipitated 125I-labeled samples of a 78-kDa gastrin-binding protein purified from membrane extracts of porcine gastrin mucosa but did not recognize the same protein labeled covalently with 125I-labeled gastrin-(2-17)-hexadecapeptide. These observations suggest that the previously identified 78-kDa gastrin-binding protein is the gastrin receptor and that the antibody 2C1 is directed against the gastrin binding site of the gastrin receptor.     

Prostate cancer detection upon transrectal ultrasound-guided biopsy in relation to digital rectal examination and prostate-specific antigen level: what to expect in the Chinese population?

We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml⁻¹ respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted.     

Mental Well‐Being Mediates the Relationship between Perceived Stress and Perceived Health

The association between stress and health has been well researched in the past; however, comparatively few mediators have been tested to understand the underlying mechanism. With increasing awareness on mental well‐being, this study evaluated the relationship between perceived stress and perceived health and examined mental well‐being as a mediator. Two‐hundred undergraduates aged 21 to 26 years completed the English Perceived Stress Scale, Health Status Questionnaire and Asian Mental Well‐Being Scale that assess perceived stress, perceived health and mental well‐being, respectively. Factor analysis and structural equation modelling on the Perceived Stress Scale replicated the reported two‐factor structure after excluding an insignificant item. Linear multiple regression analyses indicated that perceived stress was negatively associated with perceived health. Results showed that mental well‐being partially mediated the relationship between perceived stress and perceived health, although it is acknowledged that this association could be bidirectional. Findings from the present study suggest that future research could focus on reducing stress and improving mental well‐being to alleviate the effect of stress on health. Copyright © 2013 John Wiley & Sons, Ltd.     

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.     

Protective Role of Natural IgM-Producing B1a Cells in Atherosclerosis

Atherosclerosis initiated by hyperlipidemia is modulated by immune cells in its development, progression, and rupture that results in thrombotic arterial occlusion leading to strokes and myocardial infarction. B cells initially thought to be atheroprotective provide opposing roles by their different subsets. Unlike B2 cells that are atherogenic, serosal B1a cells are atheroprotective by producing natural IgM antibodies that clear modified low-density lipoprotein and apoptotic and necrotic debris. In addition to natural IgM antibodies, B1a cells may act as regulatory B cells by producing the anti-inflammatory cytokine interleukin-10, which inhibits proinflammatory cytokines secreted by activated macrophages and T cells in atherosclerotic lesions. These findings suggest in vivo expansion of atheroprotective B1a cells as a potential therapeutic strategy to augment the benefits of lipid-lowering statin therapy.     

股骨近端锁定加压钢板治疗股骨转子间骨折

目的 探讨股骨近端锁定加压钢板（LCP）内固定治疗股骨转子间骨折的临床疗效.方法 采用股骨近端LCP治疗23例股骨转子间骨折的患者.随访观察骨折愈合时间,按Harris评分标准评价疗效.结果 23例均获随访,时间6~12（9±1.4）个月.骨折愈合时间14~20（17±1.7）周.髋关节Harris评分：优13例,良9例,一般1例.结论 股骨近端LCP内固定治疗股骨转子间骨折创伤小、出血少、对骨膜影响小,符合解剖形态,临床疗效满意.