H-2 effects on cell-cell interactions in the response to single non-H-2 alloantigens. II. H-2 D region control of H-7.1-specific stimulator function in mixed lymphocyte culture and susceptibility to lysis by H-7.1- specific cytotoxic cells

The relative immunogenicity of the H-7.1 alloantigen has been shown in a previous communication to be regulated by a gene in the D region of the mouse major histocompatibility (H-2) complex. The level of relative immunogenicity was inferred from survival times of H-7.1-incompatible skin grafts donated by donors with different H-2 haplotype origins of H-2D region genes. In this communication we report the results of an extension of these previous investigations into the possible role of H-2D region genes in controlling the capacity of H-7.1-incompatible lymphocytes to stimulate H-7.1-speciflc mixed lymphocyte culture proliferation and generation of cytotoxic effector cells. The results reported herein demonstrate that the H-2D genotype of H-7.1-incompatible stimulator cells determines the relative H-7.1-specific capacity of those lymphocytes to stimulate H-7.1-specific proliferation of in vivo primed responder T cells in secondary mixed lymphocyte culture. H-2D(b)-bearing, H-7.l-incompatible stimulators were significantly more effective in stimulating H-7.1-specific proliferation than H-2D(d)-bearing stimulators. As expected, H-2D(b), H-7.1-in-compatible stimulators were also more effective than H-2D(d) a stimulators in generating H-7.1- specific cytotoxic effector cells. Further, the susceptibility of (51)Cr- labeled, H-7.1-incompatible lymphoblast targets to H-7.1-specific lysis was similarly regulated by an H-2D gene. Reciprocal H-2 restriction (F(1) cells are capable of killing only the cells bearing the immunizing cell parental H-2 haplotype) observed by other investigators for cytolysis of non-H-2-incompatible targets was not observed. H-2D a-bearing, H-7.1- incompatible stimulators stimulated generation of cytotoxic effectors capable of detectably lysing H-2D(b) but not H-2D(a)-bearing, H-7.1- incompatible targets. The impact of these observations on the proposed models for H-2 restriction of non-H-2 histocompatibility antigen-specific cytolysis is discussed.     

个性化颅骨成形术中植入材料类型与颅骨缺损面积的关系

目的：分析个性化颅骨成形术中,植入材料类型与颅骨缺损面积的关系。 方法：选择解放军总医院第二附属医院神经外科2002-03/2005-01和河北省三河市医院神经外科2003-09/2005-04收治的资料齐全的计算机辅助设计颅骨成形术患者75例,分为嵌入性材料（骨水泥、硅橡胶）组40例,根据颅骨缺损面积又分为大面积（≥36cm2）组17例和小面积（〈36cm2）组23例;覆盖性材料（钛网）组35例,大面积组14例和小面积组21例。采用头颅CT超薄扫描（层厚1.5mm）,三维重建,模拟缺损颅骨补片,应用激光快速成形技术,制作缺损颅骨及颅骨补片模型,患者认可后,根据患者的病情应用硅橡胶、骨水泥、钛网作为植入材料,进行手术植入。术后1周观察并发症：头痛、积液、松动。 结果：75例患者的补片与颅骨完整适配,塑形满意,术中无需修整,平均手术时间45min,83%（63/75）患者感到基本或完全恢复了原有容貌。手术并发症：嵌入性材料组头痛4例,积液10例,松动2例,共16例,其中大面积组13例,小面积组3例;覆盖性材料组头痛1例,积液2例,松动0例,共3例次,其中大面积组2例,小面积组1例。应用精确概率分析,两材料组之间手术并发症差异显著,两材料组颅骨缺损面积之间手术并发症差异显著,嵌入性材料大面积组与覆盖性材料大面积组之间手术并发症差异显著,嵌入性材料小面积组与覆盖性材料小面积组之间手术并发症无显著性差异。 结论：个性化设计的颅骨修补材料,能够最大限度的恢复患者外形,缩短手术时间,大面积的颅骨缺损应用钛网修补,小面积的应用钛网和嵌入性材料修补。根据患者颅骨缺损面积,选择不同植入材料,可以提高手术疗效,减少术后并发症。     

The effect of prestorage irradiation on posttransfusion red cell survival

Transfusion-associated graft-versus-host disease (TA-GVHD) may occur whenever immunologically competent allogeneic lymphocytes are transfused to an immunocompromised recipient. Irradiation of blood components eliminates the risk of TA-GVHD but may damage the cellular elements in the transfused component, particularly if the cells are stored for prolonged periods in the irradiated state. To study the effect of irradiation on long-term storage of red cells, AS-1 red cells from eight normal subjects were prepared on two occasions. On one occasion, the units were stored as standard AS-1 red cells for 42 days at 4 degrees C; on the other, they were exposed to 3000 cGy radiation within 4 hours of collection and then were stored as AS-1 red cells for 42 days at 4 degrees C. The donations were at least 12 weeks apart. Irradiated units demonstrated significant elevations in poststorage plasma hemoglobin (Hb) (623 +/- 206 vs. 429 +/- 194 g/dL [6230 +/- 2060 vs. 4290 +/- 1940 g/L], p less than 0.02) and plasma potassium (78 +/- 4 vs. 43 +/- 9 mEq/L [78 +/- 4 vs. 43 +/- 9 mmol/L], p less than 0.01) and significant decreases in red cell ATP (1.9 +/- 0.2 vs. 2.1 +/- 0.3 microM/g Hb, p less than 0.04) and 24-hour posttransfusion red cell recovery (68.5 vs. 78.4%, p less than 0.02), as compared to nonirradiated units. It can be concluded that irradiation with 3000 cGy damages red cells and that long-term storage in the irradiated state may enhance this damage. Red cells should not be stored for 42 days after irradiation with 3000 cGy.     

Prevalence of cytomegalovirus antibody in hemophiliacs and homosexuals infected with human immunodeficiency virus type 1

We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions.     

The systemic inflammatory response syndrome as a predictor of bacteraemia and outcome from sepsis

Criteria defining the <it>systemic inflammatory response syndrome</it> (SIRS) were used to assess prospectively 270 clinical episodes in which blood cultures were taken from patients in general medicine. SIRS, severe sepsis and septic shock occurred in 149 (55%), 13 (5%) and 9 (3%) episodes, respectively. However, evidence of organ hypoperfusion indicating severe sepsis was recorded as sought in only 26% of episodes of SIRS. Crude mortality at 28 days increased sequentially as more SIRS criteria were met, rising from 12% in non-SIRS blood culture episodes, to 36% when all four criteria were met. Mortality from severe sepsis and septic shock was 38% and 56%, respectively. In 61/64 (95%) episodes of clinically important bacteraemia, patients fulfilled SIRS criteria when the blood culture was taken. However, the positive predictive value of SIRS for predicting bacteraemia was only 7%. Patients who did not fulfill SIRS criteria when blood cultures were taken were at low risk of bacteraemia and comprised 45% (121/270) of the study population. Three patients in this low-risk group had bacteraemia. Mortality in bacteraemic patients with severe sepsis or septic shock who were initially treated with ineffective antibiotics for up to 48 h was 80%, compared to 42% in those always treated appropriately.      

Effect of simplification from protease inhibitors to boosted atazanavir‐based regimens in real‐life conditions

Background

Atazanavir (ATV) boosted with ritonavir (ATV/r) is a potent, well‐tolerated, once‐daily protease inhibitor (PI). Few data are available on this agent as a treatment simplification option for patients taking other PIs.

Objective

The aim of the study was to determine the effectiveness and safety of ATV‐containing regimens in patients who have simplified their antiretroviral treatment.

Methods

SIMPATAZ was a multicentre, prospective, noninterventional study in patients who had undetectable HIV RNA on their current PI‐containing therapy and who were switched to an ATV/r‐based regimen. Patients underwent a routine physical examination, and data were collected on HIV RNA levels, CD4 cell counts, liver function, lipid parameters, adverse reactions, adherence to treatment and patient satisfaction.

Results

A total of 183 patients were enrolled in the study and included in the analysis (80% were male, 29% had AIDS, and 52% were coinfected with HIV and hepatitis B virus or hepatitis C virus). The median baseline CD4 count was 514 cells/μL. Median exposure to previous HIV therapy was 8 years, and 32% of patients had a history of PI failures. Lopinavir boosted with ritonavir was the most frequent PI replaced (62%) and tenofovir+lamivudine /emtricitabine the backbone most used during the study (29%). The study drug was discontinued early by 25 patients (14%), two of whom discontinued as a result of adverse events (Hodgkin lymphoma and vomiting). Two patients died (lung cancer and myocardial infarction). At month 12, 93% of the study population had an undetectable HIV RNA viral load. Hyperbilirubinaemia >3 mg/dL and increased alanine aminotransferase levels>200 IU/L were observed in 38.5% and 4.4% of patients, respectively. Median changes from baseline to month 12 in total cholesterol, triglycerides and low‐density lipoprotein cholesterol were ?13 mg/dL (?7%; P<0.0001), ?19 mg/dL (?13%; P<0.0001) and ?7 mg/dL (?6%; P=0.021), respectively.

Conclusions

In a real‐world setting, switching from other PIs to ATV/r is a well‐tolerated and safe option for improving the lipid profile and for retaining virological response in controlled pretreated patients.

     

Screening for ‘window‐period’ acute HIV infection among pregnant women in rural South Africa

Objectives

The aim of this study was to evaluate the HIV‐1 RNA pooled nucleic acid amplification testing (NAAT) strategy to screen pregnant women in the ‘window period’ of acute HIV infection (AHI) in rural South Africa.

Methods

In 2007 and 2008, 750 consecutive pregnant women on their first antenatal care visit to a primary health care clinic were tested anonymously for HIV infection. HIV‐1 RNA pooled NAAT was performed on HIV antibody‐negative samples. All positive pools were tested individually and positive samples were classified as incident cases to calculate HIV incidence.

Results

The overall HIV prevalence was 37.3% [95% confidence interval (CI) 34.3–41.3]. Of the 467 HIV antibody‐negative samples, four (0.9%) were HIV‐1 RNA‐positive. The mean viral load in the four samples was 386 260 HIV‐1 RNA copies/mL (range 64 200–1 228 130). The HIV incidence was 11.2% per year (95% CI 0.3–22.1) and all women with AHI were ≤21 years of age.

Conclusions

Identifying AHI in pregnancy is important for health interventions to reduce perinatal and heterosexual transmission of HIV, and to estimate HIV incidence for epidemiological surveillance.     

Effects of rasagiline, its metabolite aminoindan and selegiline on glutamate receptor mediated signalling in the rat hippocampus slice in vitro

Background

Rasagiline, a new drug developed to treat Parkinson's disease, is known to inhibit monoamine oxidase B. However, its metabolite R-(-)-aminoindan does not show this kind of activity. The present series of in vitro experiments using the rat hippocampal slice preparation deals with effects of both compounds on the pyramidal cell response after electric stimulation of the Schaffer Collaterals in comparison to selegiline, another MAO B inhibitor.

Method

Stimulation of the Schaffer Collaterals by single stimuli (SS) or theta burst stimulation (TBS) resulted in stable responses of pyramidal cells measured as population spike amplitude (about 1 mV under control SS conditions or about 2 mV after TBS).

Results

During the first series, this response was attenuated in the presence of rasagiline and aminoindan-to a lesser degree of selegiline-in a concentration dependent manner (5-50 ??M) after single stimuli as well as under TBS. During oxygen/glucose deprivation for 10 min the amplitude of the population spike breaks down by 75%. The presence of rasagiline and aminoindan, but rarely the presence of selegiline, prevented this break down. Following glutamate receptor mediated enhancements of neuronal transmission in a second series of experiments very clear differences could be observed in comparison to the action of selegiline: NMDA receptor, AMPA receptor as well as metabotropic glutamate receptor mediated increases of transmission were concentration dependently (0,3 - 2 ??M) antagonized by rasagiline and aminoindan, but not by selegiline. On the opposite, only selegiline attenuated k ainate receptor mediated increases of excitability. Thus, both monoamino oxidase (MAO) B inhibitors show attenuation of glutamatergic transmission in the hippocampus but interfere with different receptor mediated excitatory modulations at low concentrations.

Conclusions

Since aminoindan does not induce MAO B inhibition, these effects must be regarded as being independent from MAO B inhibition. The results provide strong evidence for a neuroprotective activity of rasagiline and aminoindan in concert with an extended clinical indication into the direction of other diseases like Alzheimer's disease or stroke.