Stimulation of human cytotoxic T cells with HIV-1-derived peptides presented by recombinant HLA-A2 peptide complexes

HLA-A2 heavy chain and beta 2-microglobulin were expressed in Escherichia coli, and refolded in the presence of peptides derived from HIV-1 RT and gag proteins. When recombinant HLA-A2 molecules were attached to cells lacking HLA-A2, the cells became susceptible to lysis by HLA-A2-restricted cytotoxic T lymphocyte (CTL) clones specific for peptides derived from RT and gag proteins. Limiting dilution analyses of peripheral blood mononuclear cells from HIV-1-infected individuals showed that the recombinant HLA-A2 peptide complexes covalently immobilized on microspheres stimulated the development of HLA-A2 peptide-specific CTL. Preformed HLA-peptide complexes may provide an alternative to immunization procedures that depend upon intracellular processing of antigen to elicit T cell responses.      

槐定碱的气相色谱测定法及其在兔体内的药代动力学

兔血浆中槐定碱的气相色谱测定条件:氮气、氢气和空气的流速分别为60,40和380ml/min。填充柱、进样室和检测室温度分别为190,280和300℃。内标物为槐胺碱,血浆中槐定碱浓度为3.0和10.0μg/ml时,测得回收率分别为103.6±2.4%(CV=2.34%)和101.5±6.5%(CV=6.35%)。线性范围为1～15/μg/ml。槐定碱在兔体内的药代动力学按二房室拟合,其混合参数值:α.0.0864 min^-1;β.0.00932 min^-1;Vc.1.19 L/kg;V_area.2.07 L/kg;V_dvv.1.99L/kg;Cl.19.3 ml/min·kg;MRT.103min。     

部分甲基化葡萄糖的制备

以葡萄糖、甲基葡萄糖苷或可溶性淀粉为原料,适当控制反应条件进行Haworth⁽¹⁾甲基化可得到一系列不同取代数目及不同取代位置的甲基化葡萄糖(苷)。经反相HPLC分离制备后得到纯品。各产物都用气相色谱、质谱作了结构鉴定。对甲基化反应条件和HPLC分离条件进行了讨论。此法适合于实验室小量制备单糖或其甲基糖苷的甲基化标准物,供糖缀合物结构鉴定之需。     

Oligonucleotide probes to the 16s ribosomal RNA: implications of sequence homology and secondary structure with particular reference to the oral species Prevotetla intermedia and Prevotetla nigrescens

Eight oligonucleotides based upon regions of the small subunit 165 ribosomal RNA gene sequences were analysed against a background of their position within the molecule and their two-dimensional structure to rationalise their use in recognising Prevotetla intermedia and Prevotetla nigrescens . The 41 clinical isolates from both oral and respiratory sites and two reference strains were subjected to DNA-DNA hybridisation and multilocus enzyme etectrophoresis to confirm their identity. Alignment of oligonucleotide probes designated I Bi-2 to I Bi-6 (for P. intermedia ) and 2Bi-2 (for P. nigrescens ) with the 165 rRNA suggested that these probes lacked specificity or were constructed from hypervariable regions. A 52– mer oligonucleotide (designated Bi) retiably detected both species. Because of the high degree of concordance between the I 65 rRNAs of both species, it was necessary to vary the stringency of hybridisation conditions for detection of both species. Thus probe I Bi-I recognised P. intermedia while I Bi-l detected both P. intermedia and P. nigrescens at low stringency. However, under conditions of high stringency only P. nigrescens was recognised by probe 2Bi-I. These probes were highly specific and did not hybridise with DNA from the closety retated P. corporis , nor other periodontal pathogens such as Fuso-bacterium nucleatum, Actinobacillus actinomycetemcomit-ans , Treponema denticola and several pigmented species such as Prevotetla metoninogenica, P. denticola, P. loescheii, Porphyramonas osaccharolytica, Py. endodontalis, Py. gin-givalis, Py . levii, and Py. macacae .     

Ultrasound-guided venous access: “Wire-loaded puncture” technique for paediatric cancer patients

Ultrasound-guided venous access is becoming a standard technique in many centers worldwide. In small veins and in the pediatric population, successful venous puncture is sometimes followed by resistance in passing the wire. The needle seems to miss the small vein during syringe dismounting, wire mounting and wire advancement through the needle.This work describes a “wire-loaded puncture” technique as a solution for this problem.

Ilizarov External Fixator Versus Retrograde Intramedullary Nailing for Ankle Joint Arthrodesis in Diabetic Charcot Neuroarthropathy

Charcot neuroarthropathy of the ankle joint is a destructive process that leads to instability and significant morbidity that can end with amputation. Surgical arthrodesis in Charcot neuroarthropathy has a high failure rate. The aim of the present prospective study was to compare the outcomes of an Ilizarov external fixator and retrograde intramedullary nailing (IMN) for tibiotalar arthrodesis in Charcot neuroarthropathy. From February 2010 to October 2013, 27 patients (16 males and 11 females) with Charcot neuropathy of the ankle joint were treated in our department. Their ages ranged from 32 to 75 (average 54) years. Of the 27 patients, 14 received an Ilizarov external fixator and 13 underwent IMN. A preoperative clinical and radiologic assessment of all patients was performed. The outcomes were measured for bone union, development of complications, and clinical follow-up. The mean score of modified American Orthopaedic Foot and Ankle Society ankle hindfoot scale was 80 ± 2.7 points in the Ilizarov group and 75 ± 1.9 points in the IMN group. In the Ilizarov group, 12 of 14 patients achieved union, and in the IMN group, 10 of 13 patients achieved union. The complication rate was significantly greater in the external fixator group than in the IMN group. The complications in the Ilizarov group included nonunion in 2 patients (14%), pin tract infection in 8 (57%), pin tract loosening in 3 (21%), surgical wound infection in 3 (21%), and wound breakdown in 1 patient (7%). In the IMN group, nonunion occurred in 3 patients (23.1%), back-out of a distal locking bolt in 2 (15.4 %), and a superficial wound infection that resolved with antibiotics in 1 patient (7.7%). In conclusion, retrograde IMN and the Ilizarov external fixator both yielded better union for tibiotalar arthrodesis in Charcot neuroarthropathy. The Ilizarov external fixator resulted in a greater union rate than IMN but the complications with external fixation were significantly greater than those with IMN.     

Significance of assay of nucleated RBCs in umbilical cord blood in neonates with meconium-stained amniotic fluid

Background: Approximately 8–15% of all infants are born with evidence of meconium-stained amniotic fluid (MSAF). MSAF is a potentially serious sign of fetal compromise and may indicate fetal hypoxia

Objectives and aim of the work: The present study was designed to evaluate the relationship between meconium stained amniotic fluid and fetal nucleated red blood cell counts. As well, we aim to evaluate the relationship between the presence of meconium in amniotic fluid and Apgar scores in neonates.

Subjects and methods: A prospectively case-controlled study was performed on 40 women with clear amniotic fluid as control and 40 women with meconium-stained amniotic fluid as the study group. At delivery, 2?ml of umbilical cord blood was collected and analyzed for nucleated red blood cell (NRBC).

Results: The mean NRBC counts in meconium-stained amniotic fluid was significantly higher than the control group (18.35?±?7.7 and 9.6?±?4.96), respectively (p?p?Conclusion: Our results support previous studies which indicate the presence of meconium can be associated with chronic fetal hypoxia as demonstrated by elevated fetal NRBC levels.     

Peritoneal interleukin-10 increases with decrease in activated CD4+ T lymphocytes in women with endometriosis

This study was performed to determine whether peritoneal T cells are suppressed in the CD4+ or CD8+ T cell subpopulation and whether they are Th1 or Th2 predominant in women with endometriosis. Immune cells in the peritoneal fluid (PF) were obtained from women undergoing laparoscopy for endometriosis or tubal ligation. Three-colour flow cytometry was utilized for immunophenotyping of peritoneal fluid mononuclear cells (PFMC). Concentrations of interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma) produced by PFMC with and without mitogen stimulation and concentrations of IL-10 and IL-12 were measured in PF. The peritoneal T lymphocytes were predominantly of the Th1 type that produced much more IFN-gamma but less IL-4 or IL-5 in women with or without endometriosis. The decrease in peritoneal lymphocytes was significant in the HLA-DR+ CD4+ CD3+ subpopulation and the concentrations of peritoneal IL-10 and IL-12 were significantly elevated in women with early stage endometriosis. There was impaired IL- 5 production by PFMC after phytohaemagglutinin stimulation in women with advanced stage endometriosis. We concluded that the activated peritoneal CD4+ Th1 cells from the women with endometriosis were decreased in number. The suppression of these T cells may be due to the elevation of IL-10 and IL-12 in the peritoneal fluid.      

Paired human chorionic gonadotrophin determinations for the prediction of pregnancy outcome in assisted reproduction

The aim of this study was to determine the prognostic value of single and paired measurements of serum concentrations of human chorionic gonadotrophin (HCG) for successful pregnancy following in-vitro fertilization (IVF) and tubal embryo transfer (TET). We analysed serum HCG concentrations 15 and 22 days after IVF or TET in 198 conception cycles. Cut-off values of serum HCG were determined by a receiver operating characteristic (ROC) curve. On the basis of single HCG samples on day 15 (HCG15) after transfer, using a cut-off value of HCG15 = 150 mIU/ml, the sensitivity was 71% and the specificity was 77%. The positive predictive value (HCG15 > or = 150 mIU/ml indicating a normal pregnancy) was 89%, while the negative predictive rate (HCG15 < 150 mIU/ml indicating an abnormal pregnancy) was 51%. Patients with HCG15 < 150 mIU/ml but HCG22/HCG15 ratio > or = 15, still had a 90% chance of normal pregnancy. However, in patients with HCG15 < 150 mIU/ml and an HCG22/HCG15 ratio < 15, there was an 84% chance of an abnormal pregnancy. We conclude that a single HCG15 determination combined with the ratio of HCG22 to HCG15 has a higher diagnostic accuracy for prediction of pregnancy outcome than either analysis alone.