LHRH-A对孕中期大鼠抗妊娠作用的研究

本文观察了[D-Ala⁶,Pro⁹-Ethylamide¹⁰]-LHRH(LHRH-A)对孕中期大鼠的抗妊娠作用。结果显示:在孕9～11d sc 200μg/d LHRH-A,血浆孕酮水平自第二次给药后明显下降(P<0.05),给药大鼠均流产终止妊娠;LHRH-A的抗妊娠作用可被醋酸甲地孕酮所拮抗;LHRH-A对体外培养的假孕大鼠和孕d 9大鼠黄体细胞分泌孕酮有明显的直接抑制作用。     

Integrin stimulation regulates polymorphonuclear leukocytes inflammatory cytokine expression.

OBJECTIVE: The purpose of these studies is to investigate the role of integrin binding on the regulation of polymorphonuclear leukocyte (PMN) cytokine receptor expression. SUMMARY BACKGROUND DATA: Current knowledge in this area revolves around the ability of beta 2 integrins to mediate PMN adherence and chemotaxis. The role of alpha 1-6/beta 1 integrins in regulating cytokine receptor expression has not been probed. METHODS: Purified human PMN were adhered on plastic, fibronectin, or laminin-coated surfaces followed by the addition of iodine 125 (125I) monoclonal antibodies (mAbs) directed against tumor necrosis factor-alpha R (TNF-alpha R) p60, p80, or interleukin-1 beta R (IL-1 beta R) types I, II. Receptor expression was calculated based on the counts per minute (cpm) bound. The role of individual beta 1 integrins was assessed using mAbs directed against the alpha 1-6 subunit of the beta 1 complex, and integrin cross-linkage was achieved using secondary goat antimouse F(ab')2 antibodies. Polymorphonuclear leukocytes were pretreated with herbimycin A to determine the role of protein tyrosine kinase in mediating the effect of the beta 1 integrins. RESULTS: Adherence of PMN to Ln decreased IL-1 beta types I, II receptor expression, whereas adherence to Fn increased TNF-alpha R p60 and p80 expression. Anti-VLA-5 (CD49e) but not anti-VLA-1 through VLA-4 and VLA-6, blocked the effect of Fn on TNF-alpha receptors, whereas anti-VLA-6 but not anti-VLA-1 through VLA-5 blocked the effect of Ln on IL-1 beta receptors. Modulation of IL-1 beta and TNF-alpha receptors by VLA-5 and VLA-6 required protein tyrosine kinase activation as herbimycin A (10 micrograms/mL) blocked the affect of Fn and Ln. Changes in PMN cytokine receptor expression led to parallel changes in functional activity as assessed by the binding of 125I IL-1 beta and TNF-alpha. CONCLUSIONS: Integrin stimulation regulates the cell surface expression of PMN cytokine receptors. Ligation of CD49e upregulates TNF-alpha receptor expression, whereas binding of CD49f downregulates IL-1 beta receptor expression. Both processes are protein tyrosine kinase dependent. Changes in PMN cytokine receptor expression led to corresponding changes in functional activity. These results provide the first demonstration that chemotaxis of PMN into the interstitium provides a mechanism for ongoing participation in the local inflammatory response and is regulated by matrix protein integrin receptors.     

Career advancement of nurse executives: planned or accidental?

This exploratory study has examined the effect of selected characteristics on the career advancement patterns of nurse executives in service and educational settings. The findings are not consistently in agreement with those of other researchers. For example, Hall et al. found that nearly two-thirds of nursing deans had planned their careers to attain that position. In this study, however, eighty-three percent of the respondents indicated that they had not planned their career advancement, but had simply taken opportunities that had come their way. The influence of others was important in the career advancement of these administrators. Many individuals, including faculty and nursing service colleagues, nursing directors, deans, and non-nursing administrators supported the respondents' personal and professional development through role modeling, teaching skills, and encouragement. Deliberate career planning and education in administration were, for the most part, lacking. Although the sample is too small to generate general conclusions about the universe of nurse executives, this does suggest that it is not uncommon for deans and service administrators to learn necessary skills on the job.     

Recurrent aorto-duodenal fistula: a final solution?

This paper describes a case of recurrent aorto-duodenal fistula treated successfully by re-sitting the duodenum in an ante-colic position. Secondary aorto-duodenal fistula affects less than 1% of patients who have received a prosthetic abdominal aortic graft. However following correction of such a fistula the incidence of recurrent fistulation or aortic stump blow-out is reported as high as 47%. we describe an alternative approach to management of this difficult problem.     

Excessive fibrinolysis in amyloidosis associated with elevated plasma single-chain urokinase.

Severe bleeding resulting from excessive fibrinolysis has been observed in patients with primary amyloidosis. The authors studied a patient with this hemostatic disorder before and during therapy with epsilon-aminocaproic acid. Excessive fibrinolysis was associated with depressed plasma concentrations of coagulation Factors XII, XI, high-molecular-weight kininogen, and Factors VIII and V; and plasminogen and alpha-2-plasmin inhibitor. These deficiencies were corrected with treatment. The functional and antigenic concentrations of tissue plasminogen activator and plasminogen activator inhibitor in the patient's plasma were normal. Urokinase-type activator activity and antigen were three to five times elevated in the patient's plasma. Results of immunoprecipitation showed that single-chain urokinase-type activator was the primary urokinase-type activator species in the patient's plasma. Excessive fibrinolysis in patients with amyloidosis results from increased plasma single-chain urokinase-type activator activity.     

GGA1 acts as a spatial switch altering amyloid precursor protein trafficking and processing

The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.     

Evaluation and audit in a paediatric disability service

Parental and professional responses to questionnaires evaluating a paediatric disability service are reported and the viability of auditing structural, process, and outcome aspects of clinical practice are discussed. Expectations of waiting time to first appointment (met for only 52% of consumers) illustrate structural issues. Process issues are reflected in consumer reactions to outreach work (for example, 94% of parents and 84% of professionals found this supportive). Outcome measures such as consumer satisfaction with the service (76% of consumers reported being 'very satisfied' and 20% 'fairly satisfied') suggest that service aims are being met. Good concurrence of service aims with consumer needs is indicated by parental reasons for referral (for example, 75% for diagnostic help, 73% for a better understanding of the disorder, 88% for practical help), referrers' reasons (for example, 55% for a second diagnostic opinion, 45% due to lack of local expertise), and reports from most other professionals involved with the case that a similar service was not provided locally.     

Immune responses in mice infected with lactic dehydrogenase virus. IV. Functional status of the macrophage during acute LDV infection.

Macrophages from uninfected and lactic dehydrogenase virus (LDV)-infected mice were compared with respect to the affinity and number of their Fc receptors for IgG2a; no differences were found regarding these parameters. When the uptake of DNP-BGG by macrophages from uninfected and acutely LDV-infected mice was compared, again no differences were observed. However, when the per cent membrane-bound DNP-BGG was determined as a function of time after antigen uptake in these two groups, more DNP-BGG was found membrane-bound on the macrophages from the LDV-infected mice, than on uninfected macrophages. In view of the fact that humoral immunity is enhanced during acute LDV infection, these data provide a positive correlation between increased retention of membrane-bound antigen and enhanced humoral immune responses.     

Application of a noninvasive oral fluid test for detection of treponemal IgG in a predominantly HIV-infected population

The performance of a time-resolved fluorescence immunoassay (TRFIA) for detection of treponemal IgG from oral fluid specimens has been assessed in a predominantly HIV-infected population. Serological investigation is the method of choice for confirming clinical suspicion of syphilis; however, in the primary stage of disease, direct detection of treponemes in lesion fluid or Treponema pallidum DNA is recommended because of the reduced sensitivity of serological tests. There may be occasions when blood for serological investigation is difficult to obtain due to individual patient preference or logistical necessity to improve participation in screening initiatives, particularly in outreach situations. Collection of oral fluid for detection of treponemal antibody may prove an attractive alternative and, with this in mind, an oral fluid assay for detection of treponemal IgG was developed. Time-resolved fluorescence was used to detect treponemal IgG extracted from commercially available oral fluid collection devices. Paired serum and saliva samples were obtained from 210 individuals, 101 of whom were diagnosed with syphilis on the grounds of medical examination confirmed by serological testing. Oral fluid specimens from 14 subjects were rejected because they contained insufficient control antibody or were inhibitory. The population tested was predominantly men who have sex with men, many of whom were HIV infected. The overall sensitivity and specificity of the oral fluid assay was 95.8 and 86.1%, respectively, based on the 5th percentile of the positive results, and 93.7 and 91.1%, respectively, based on a cutoff derived by mixture model analysis. For individuals with primary syphilis, the optimum sensitivity of the oral fluid assay was 87.5%, whereas in those with disease classified as secondary syphilis and early latent syphilis, the sensitivity of the oral fluid assay was 100 and 94.7%, respectively. The oral fluid assay is a useful alternative to serological testing in certain situations, and further development of this technology to enable detection of treponemal IgM should increase its sensitivity for detecting cases of primary syphilis.