Measurement of the vasoconstrictive substances endothelin,angiotensin II,and thromboxane B2 in cold storage solution can reveal previous renal ischemic insults

In a rat model, the left kidney was subjected to 60 min of normothermic ischemia followed by 15 min of reperfusion, whereas the right kidney, serving as a paired control, was not rendered ischemic. Both kidneys were then perfused in situ with either Euro-Collins (EC) solution (n=12) or University of Wisconsin (UW) solution (n=6) for 10 min. Each kidney was then harvested and stored at 4°C in its respective solution. After 24 and 48 h of cold storage, the following vasoactive substances were measured in the preservation media: endothelin (ET), angiotensin II (A-II), thromboxane (B₂) (TxB₂), and prostaglandin I₂ (PGI₂). After 24 h in EC solution, left kidneys uniformly produced significantly higher concentrations of each vasoactive substance than right kidneys: ET 1.64±0.3 pg/ml vs 0.82±0.1 pg/ml (P0.009); A-II 20.8±6.2 pg/ml vs 7.75+2.3 pg/ml (P0.007); TxB₂ 100.8±17.7 pg/ml vs 40.1±11.7 pg/ml (P0.04); PGI₂ 638.3±41.1 pg/ml vs 318.3±36.4 pg/ml (P0.001), respectively. At 48 h, a similar pattern of results was obtained as the kidney continued to produce TxB₂ and prostacyclins during the 24–48 h period. In the UW solution, basal levels of ET and A-II were lower than those in EC solution, but similarly increased after initial ischemia. At 24 h, the concentrations produced by the left and right kidneys were as follows: ET 0.66±0.1 pg/ml vs 0.48±0.1 pg/ml (P0.14); A-II 10.36±3.7 pg/ml vs 2.14±0.7 pg/ml (P0.006); TxB₂ 178±53 pg/ml vs 52±23.1 pg/ml (P0.001); and PGI₂ 448.3±49 pg/ml vs 323±44.3 pg/ml (P0.01), respectively. After 48 h, the range of concentrations of each substance was similar to that obtained after 24 h. In further studies, the concentrations of ET and A-II were measured in solution previously used to preserve human kidneys (n=7). The mean concentration of ET and A-II in these samples was 3.82±1.14 pg/ml and 21.3±9.2 pg/ml, respectively, whereas in control media both substances were below the limits of detection. These results demonstrate that vasoconstrictive substances can be measured in the preservation media after a kidney has been stored cold and that higher concentrations are found when the organ has been subjected to prior normothermic ischemia. The measurement of these vasoactive substances before transplantation may reveal that the kidney has been subjected to previous ischemic events. Moreover, these vasoactive substances could be involved in the early recovery of renal function after kidney transplantation.     

A Retrospective Assessment of Canadian Preterm Birth Prevention Efforts: 1979–1999

Objectives: To assess the achievements and effectiveness of efforts to reduce preterm deliveries through the collaborative efforts of funding agencies, scientists, obstetricians, pediatricians, and health care providers in Canada. Methods: Chronological review of studies carried out in Canada within the past two decades using several methodological approaches, including randomized clinical trials, surveys of women and physicians, and prospective cohort studies. Results: Tertiary prevention by treatment of spontaneous preterm labor with beta-agonists was effective in delaying delivery by 48 hr compared with placebo. Ongoing studies tested the comparative efficacy of oxytocin antagonists to beta-adrenergic agents. Recently, nitric oxyde donors have been tested. Secondary prevention using various approaches showed that high-risk factors could not be modified by these interventions. Before applying primary prevention approaches, surveys disclosed the lack of knowledge among both physicians and pregnant women. Conclusion: A recent Canadian consensus meeting emphasized the potential for success by using multidisciplinary, community-based health promotion approaches to prevent preterm labor; enhancing basic research in predictive markers such as cervical change, infection/inflammation, and psychosocial stress; and increasing political involvement of health decision makers.     

Randomized, Prospective, Controlled Study Comparing Radical Prostatectomy Alone and Neoadjuvant Androgen Withdrawal in the Treatment of Localized Prostate Cancer

Purpose

A prospective, multicenter, randomized study was done to test the hypothesis that neoadjuvant androgen withdrawal decreases the incidence of positive margins following radical prostatectomy for localized prostate cancer.

Materials and Methods

Observations were made of 213 patients randomized to undergo radical prostatectomy alone (101) or to receive a 12-week course of 300 mg. cyproterone acetate daily followed by surgery (112). Groups were similar at baseline in terms of clinical stage, serum prostate specific antigen and Gleason score. Of 192 patients available for efficacy analysis 9 had stage T1b, 8 stage T1c, 63 stage T2a, 36 stage T2b and 76 stage T2c disease.

Results

One or more positive surgical margins were found in 59 of 91 patients (64.8 percent) in the surgery only group compared to 28 of 101 (27.7 percent) in the cyproterone acetate group (p = 0.001). Patients who received preoperative therapy had a statistically significantly lower rate of apical margin involvement than those who did not (17.8 versus 47.8 percent, respectively, p less than 0.0001). There was no statistically significant difference in surgical (p = 0.8645) or postoperative (p = 0.173) complications between the 2 groups.

Conclusions

Neoadjuvant androgen withdrawal with a 12-week course of 300 mg. cyproterone acetate daily results in a lower rate of positive margins without adversely affecting postoperative recovery. The impact on patient survival will be determined by long-term followup.     

Management of soft tissue sarcomas (STS) in first isolated local recurrence: a retrospective study of 83 cases.

PURPOSE: To analyze the management and clinical outcome of patients treated for a first isolated local recurrence of soft tissue sarcomas (trunk or extremities) and to identify prognosis factors. METHODS AND MATERIAL: Between 1980 and 1999, 83 adult patients were included in the study. Mean age was 61 years. Mean tumor size was 6 cm. Most sarcomas were located in extremities (n=74), were deep (n=60), and proximal (n=53); 30 involved nerves or vessels. Histologic subtypes were mainly grade 2 (42%) or 3 (36%) histiocytofibrosarcomas (49%) and liposarcomas (20%). Surgical treatment of recurrences consisted in wide excision (29 cases), marginal resection (43 cases), 5 patients requiring amputation. Final results were R0 (n=33), R1 (n=47) or R2 (n=3) resection. Besides surgery, 6 patients received neo-adjuvant and 7 others adjuvant chemotherapy. Twenty three patients received post-operative external beam radiotherapy (EBRT) (mean dose 55 Gy) and 26 interstitial 192Ir low dose rate brachytherapy (BCT) (mean dose 45 Gy for BCT alone, 22 Gy when associated with EBRT), 19 patients being re-irradiated. RESULTS: Mean follow up was 13 years. Thirty-seven (45%) patients relapsed, 62% of whom presenting an isolated local recurrence. Nineteen patients developed distant metastases. Multivariate analysis showed only tumor depth (P=0.05) and re-resection for primary R1 resection (P=0.018) being independent prognosis factors for tumor control, radiotherapy (EBRT and/or BCT) being significant in univariate analysis (P=0.05). Overall survival rate was 73%, 54%, and 47% at, respectively, 3.5 and 10 years, and was 65%, 35% and 32% after a further local recurrence. Multivariate analysis showed trunk (P=0.0001) or inferior extremity locations (P=0.023), symptomatic (P=0.001), high grade (P=0.01), deep (P=0.01) tumors, and the occurrence of a further local failure (P=0.004) as unfavorable characteristics for overall survival. CONCLUSIONS: A first isolated local recurrence of STS increases mainly the risk of a subsequent local relapse. Quality of local treatment is decisive. When a conservative treatment is feasible, it should combine surgical resection and radiotherapy, BCT being the best suited in previously irradiated patients. Efforts have to be pursued to increase quality of the treatment of primary tumors, at best performed in centers that have expertise in this field.     

Incidence of non-AIDS-defining cancers before and during the highly active antiretroviral therapy era in a cohort of human immunodeficiency virus-infected patients.

PURPOSE: To determine incidence of non-AIDS-defining cancers (NADC) in HIV-infected patients before (P1) and during (P2) the use of highly active antiretroviral therapy (HAART) relative to that observed in the French general population (FGP) of the same age and sex. PATIENTS AND METHODS: Sex- and age-adjusted NADC standardized incidence ratios (SIR), with FGP as reference, were estimated in 1992 to 1995 (P1) and in 1996 to 1999 (P2) in a French Hospital Database on HIV prospective hospital cohort study. RESULTS: NADCs were diagnosed in 260 patients during P1 and 391 patients during P2 among the 77,025 patients included in the database between January 1, 1992, and December 31, 1999. Estimated incidence of all cancers was higher in HIV-infected men than in FGP during both periods (P1 SIR = 2.36 and P2 SIR = 1.91). No excess of cancers was observed among HIV-infected women in either period. Incidence of all cancers did not change from P1 to P2 in either sex (SIR = 0.96 for men and 1.00 for women). In contrast, incidence of Hodgkin's disease (HD) was higher than in FGP in both sexes and both periods and increased in P2 as compared with P1; incidence of lung cancer was higher in both sexes during P2. CONCLUSION: Relative to FGP, the overall incidence of NADCs was increased in HIV-infected men but not in women and did not differ between P1 and P2. Only HD was much more common in HIV infection, and the potential role of HAART on HD cannot be excluded.     

Lithocholic acid decreases expression of UGT2B7 in Caco-2 cells: a potential role for a negative farnesoid X receptor response element.

Human UDP-glucuronosyltransferase (UGT) 2B7 is the major isoform catalyzing the glucuronidation of a variety of endogenous compounds including bile acids. To determine the role of bile acids in the regulation of UGT2B7 expression, Caco-2 cells were incubated with the natural human farnesoid X receptor (hFXR) ligand, chenodeoxycholic acid, as well as the secondary bile acid, lithocholic acid, derived from chenodeoxycholic acid. Incubation of Caco-2 cells with lithocholic acid in the absence of exogenous hFXR resulted in a dose-dependent down-regulation of UGT2B7 mRNA levels, with an IC(50) of 13 microM. Similar down-regulation was also observed with chenodeoxycholic acid; however, much higher concentrations were required. Transient transfection of Caco-2 cells with hFXR suppressed UGT2B7 mRNA expression both in the absence and presence of ligand. UGT2B7 promoter transfection experiments and deletion/mutation analysis showed that lithocholic acid-activated hFXR decreased UGT2B7 promoter activity via a negative hFXR response element (NFRE) located between nucleotides -148 and -134. Cotransfection with hFXR and/or human retinoid X receptor further enhanced the repression. Electrophoretic mobility shift assays additionally confirmed the role of NFRE in UGT2B7 down-regulation by lithocholic acid. These findings suggest that lithocholic acid, an activator of nuclear hFXR, acts as a negative regulator of UGT2B7 expression, indicating that hFXR may play an essential role in lithocholic acid homeostasis through negative regulation of this UGT that is involved in lithocholic acid biotransformation. Therefore, it is postulated that lithocholic acid toxicity may be due to down-regulation of genes involved in its detoxification, including UGT2B7, leading to limited excretion of lithocholic acid from the body.     

Localisation of drug permeability along the rat small intestine, using markers of the paracellular, transcellular and some transporter routes

The small intestine is the major site of drug absorption. Some reports in the literature have evoked the concept of “absorption windows” in the small intestine: are there specific regions where drug absorption is significantly higher than others? To investigate this question, we used an everted gut sac method to study the permeability of drugs and markers every 3–4 cm down the entire small intestine in rat. These markers were chosen to be representative of the mechanisms by which drugs cross the small intestinal mucosa: paracellular and transcellular passive diffusion, via influx transporters, and a drug (digoxin) that is effluxed from cells by P-glycoprotein (P-gp). The passive diffusion and influx transporter markers gave similar profiles with a plateau of permeability along the jejunum, and with the exception of L-Dopa, lower permeability in the ileum. Digoxin showed a linear decrease in the profile from the proximal jejunum to the ileum. Permeability in the duodenum was two to three times lower than the jejunum for all compounds. There were no narrow specific regions of high permeability and so the concept of discrete “absorption windows” along the small intestine as suggested from some pharmacokinetic studies may be related to other effects such as pH and/or solubility.     

Characterization of T cell receptors reactive to HCRTNH2, pHA273-287, and NP17-31 in control and narcolepsy patients

Narcolepsy type 1 (NT1), a disorder caused by hypocretin/orexin (HCRT) cell loss, is associated with human leukocyte antigen (HLA)-DQ0602 (98%) and T cell receptor (TCR) polymorphisms. Increased CD4⁺ T cell reactivity to HCRT, especially DQ0602-presented amidated C-terminal HCRT (HCRT_NH2), has been reported, and homology with pHA_273–287 flu antigens from pandemic 2009 H1N1, an established trigger of the disease, suggests molecular mimicry. In this work, we extended DQ0602 tetramer and dextramer data to 77 cases and 44 controls, replicating our prior finding and testing 709 TCRs in Jurkat 76 T cells for functional activation. We found that fewer TCRs isolated with HCRT_NH2 (∼11%) versus pHA_273–287 or NP_17–31 antigens (∼50%) were activated by their ligand. Single-cell characterization did not reveal phenotype differences in influenza versus HCRT_NH2-reactive T cells, and analysis of TCR CDR3αβ sequences showed TCR clustering by responses to antigens but no cross-peptide class reactivity. Our results do not support the existence of molecular mimicry between HCRT and pHA_273–287 or NP_17–31.

Narcolepsy type 1 (NT1) is caused by a loss of hypocretin/orexin (HCRT) neurons in the mediolateral hypothalamus (1–3), with recent data suggesting reversion of the human and animal phenotype with orexin agonists. The disease is strongly associated with human leukocyte antigen (HLA) DQB1*06:02/DQA1*01:02 (98% vs. 25%) (DQ0602) and displays weaker genetic associations with other immune loci, thus suggesting autoimmunity (4–9), although not meeting all criteria for being classified as an autoimmune disease (10). Like other autoimmune diseases, NT1 presents with increased comorbidity with other autoimmune conditions and asthma (11–13).Onset of NT1 is often abrupt and seasonal, and association with both Streptococcus pyogenes (14, 15) and influenza A infections (16) suggests that it may be triggered by winter infections. Most strikingly, prevalence of NT1 increased several folds in mainland China and Taiwan following the 2009 to 2010 “swine flu” H1N1 influenza pandemic (pH1N1) (4, 17, 18), although association with the pandemic is less clear in other countries (19). Vaccination with the pH1N1 vaccine Pandemrix has also been associated with an elevated relative risk for developing narcolepsy of 5- to 14-fold in children and adolescents and 2- to 7-fold in adults (18, 20–22). As Pandemrix is an AS03-adjuvanted vaccine containing the artificially produced reassortant strain X-179A, a mix of A/Puerto Rico/8/1934 (PR8), an old H1N1 strain derived from pre-2009 seasonal H1N1, and the key H1N1 2009 surface proteins hemagglutinin (HA) and neuraminidase (NA) (23), flu proteins are likely critically involved in triggering NT1. Evidence showing that HLA and T cell receptor (TCR) genetic associations are universal (9, 24–27) is also consistent with a flu trigger, as influenza A infections occur on a global basis (28). Importantly, however, even with Pandemrix vaccination in Europe, only ∼1 in 16,000 vaccinated children developed NT1, thus demanding the consideration of additional factors to fully explain the initiation of NT1 (29).Unlike in other autoimmune diseases, autoantibodies against HCRT cell proteins, HCRT itself (30–32), or other targets such as TRIB2 (33, 34) or HCRT receptor 2 (35–38) have not been consistently found. This has led to the suggestion that HCRT cell loss may be primarily T cell mediated, with limited or no involvement of autoantibodies. Consistent with this hypothesis, mounting evidence suggests involvement of CD4⁺ T cell reactivity to HCRT in NT1 (39–41), notably toward amidated fragments of the secreted, mature peptide (HCRT_54–66-NH2 and HCRT_86–97-NH2, homologous peptides collectively denoted as HCRT_NH2) (42), as critical factors in the development of the disease. Furthermore, CD8⁺ mediation of HCRT cell death has also been shown to cause NT1 in an animal model (43) and Pedersen and colleagues (44) recently highlighted the presence of CD8⁺ T cell responses against intracellular proteins contained in HCRT neurons in narcolepsy patients. Of additional interest is the observation that the TCR polymorphisms associated with NT1 are quantitative trait loci for TRAJ24 (decreasing), TRAJ28, and TRBV4-2 (increasing) usage in peripheral T cells in both controls and patients (29). A significant L to F coding polymorphism located within the antigen-binding complementarity-determining region (CDR) 3 loop of TRAJ24 expressing TCRs is also associated with NT1. Altogether, this suggests that T cell responses involving TRAJ24- or TRAJ28- and TRBV4-2–bearing TCRs may be bottleneck responses in a causative autoimmune T cell response, leading to HCRT cell death (4, 14, 17–19, 45).Based on the evidence provided above, our group hypothesized that a CD4⁺ T cell–mediated response directed against specific flu epitopes could lead to molecular mimicry with HCRT itself, potentially HCRT_NH2, subsequently recruiting CD8⁺ cytotoxic T cells and leading to HCRT cell death. To test this hypothesis, we screened 135 DQ0602 tetramers binding peptides originating from Pandemrix, wild-type 2009 H1N1, and two autoantigens (HCRT and RFX4) for the presence of antigen-restricted CD4⁺ T cells (42). After this systematic survey, it was established that CD4⁺ T cell populations recognizing influenza pHA_273–287 (pH1N1 specific) and PR8 (H1N1 pre-2009 and H2N2)-restricted NP_17–31 epitopes were increased in NT1 versus DQ0602 controls. Supporting this finding, this difference was also present in post-Pandemrix cases versus controls and was stronger in recent onset cases (42). Additionally, studies of single cells recognizing these peptides revealed that TCR clones carrying TRBV4-2 and TRAJ24 were retrieved from both HCRT_NH2 and pHA_273–287 tetramers (42), suggesting involvement of these clones in molecular mimicry and disease pathophysiology. Similarly, Jiang et al. (39) isolated TRAJ24-positive cells recognizing DQ0602 bound to HCRT_87–100 tetramer, many of which expressed perforin and granzyme-B, suggesting a terminally differentiated effector T cell (T_EMRA) phenotype. In one case, a TRAJ24 clone isolated from a narcoleptic patient showed elevated TCR reactivity toward HCRT_87–97-NH2 when transfected in Jurkat 76 (J76) cells, thus implying a role for TRAJ24 reactivity toward DQ0602-HCRT in narcolepsy autoimmunity (39).Here, we extend prior work from our group by doubling the number of patients and controls and increasing the representation of TRAJ24F narcolepsy susceptibility–associated alleles in these subjects. Results validated an increased frequency of pHA_273–287 and HCRT_54–66-NH2 tetramer-positive CD4⁺ T cells in NT1, while also testing isolated T cell clones for potential activation by their cognate ligands when expressed in J76 cells. Importantly, we also analyzed TCR CDR3αβ sequences in this larger dataset and conducted expression profiling of the corresponding T cells, providing insights into T cell characteristics in narcolepsy.     

海南省HIV-1基因亚型分析

目的 分析海南省人类免疫缺陷病毒-1(HIV-1)基因亚型,监测HIV毒株的流行状况.方法 从88份HIV-1抗体阳性的血浆中提取RNA,逆转录后采用PCR法扩增HIV-1基因序列中的env及pol基因,对扩增产物进行核苷酸序列测定,经比对分析而确定基因亚型.构建最大似然(ML)进化树,分析感染者间的传播链.结果 88份样品中,有83份样品被扩增出HIV-1的env及pol基因片段;共发现6种HIV-1亚型和重组型,其中CRF01-AE亚型70份,B'亚型8份,C亚型2份,B亚型和CRF08-BC、CRF01-AE/B'重组亚型各1份.在ML进化树上83份样品分成4个传播群(66/83)和非传播群(17/83),其中传播群1最庞大(59/83).结论 海南省HIV/AIDS的HIV-1基因亚型至少有6种,其中CRF01-AE为主要亚型,占84.33%(70/83),主要分布在静脉吸毒者及其性伴侣之间,形成了一个庞大的传播群.其次为B'亚型(9.6%).另外的4种亚型(6%)仅见单个病例.提示海南省静脉吸毒为主要的感染途径(67.5%);经性接触传播的亚型种类复杂多样,包括本次检出的全部亚型和重组株.