Genetic variability in Puccinia striiformis f. sp. tritici populations sampled on a local scale during natural epidemics

This study investigated genetic polymorphism on a local scale in Puccinia striiformis f. sp. tritici populations during natural epidemics, in four fields located in northern France and sampled in 1998 or 1999. Two hundred and forty-seven isolates were analyzed for their amplified fragment length polymorphism (AFLP) pattern through four primer combinations, and 194 of them were also tested for their virulence factors. Only one or two pathotypes were found in each field, and all isolates had virulence v17, matching the recently introduced Yr17 resistance gene. Polymorphism on a field scale was low. Although 67 loci were polymorphic, 77% of the isolates had the same AFLP pattern, all other patterns being rare or unique. Analyses of the genetic distance between AFLP patterns based on the Jaccard index allowed us to define 12 groups, but a bootstrap analysis showed that all isolates could be assigned to a single clonal lineage. This leads us to conclude that P. striiformis f. sp. tritici populations are clonal on a field scale in northern France.     

Antigen-driven oligoclonal expansion of tumor-infiltrating B cells in infiltrating ductal carcinoma of the breast

The objective of this study was to determine whether tumor-infiltrating B cells (TIL-B) of infiltrating ductal carcinoma (IDC) of the breast represent a tumor-specific humoral immune response. Immunohistochemical analysis of three Her-2/neu-negative IDC tumors from geriatric patients showed that TIL-B cluster in structures similar to germinal centers containing CD20(+) B lymphocyte and CD3(+) T lymphocyte zones with interdigitating CD21(+) follicular dendritic cells, suggesting an in situ immune response. A total of 29, 31, and 58 IgG1 H chain clones was sequenced from the three IDC tumors, respectively. Intratumoral oligoclonal expansion of TIL-B was demonstrated by a preponderance (45-68%) of clonal B cells. In contrast, only 7% of tumor-draining lymph node and 0% of healthy donor PBL IgG H chains were clonal, consistent with the larger repertoires of node and peripheral populations. Patterns and levels of TIL-B IgG H chain somatic hypermutation suggested affinity maturation in intratumoral germinal centers. To examine the specificity of TIL-B Ig, a phage-displayed Fab library was generated from the TIL-B of one IDC tumor. Panning with an allogeneic breast cancer cell line enriched Fab binding to breast cancer cells, but not nonmalignant cell lines tested. However, panning with autologous tumor tissue lysate increased binding of Fab to both tumor tissue lysate and healthy breast tissue lysate. These data suggest an in situ Ag-driven oligoclonal B cell response to a variety of tumor- and breast-associated Ags.     

Analysis of highly phosphorylated inositols in avian and crocodilian erythrocytes

Both morphological and paleontological characteristics support the hypothesis of a monophyletic origin of crocodilian and avian groups. However, while the erythrocytes of all birds studied to date are reported to contain high levels of inositol pentakisphosphate (InsP(5)), which acts as an allosteric effector of hemoglobin, this molecule has not been reported in crocodilian erythrocytes. In this study we compare the highly phosphorylated inositols in crocodilian and avian erythrocytes using a particularly sensitive analytical procedure. Our aim was to obtain new data which might provide further evidence for the monophyletic origin, or otherwise, of crocodiles and birds. We studied three avian and three crocodilian species. The erythrocytes of the three bird species contained low levels of inositol-3,4,5,6-tetrakisphosphate and inositol-1,3,4,6-tetrakisphosphate, thought to be precursors of Ins(1,3,4,5,6)P(5). The crocodilian erythrocytes studied contained Ins(1,3,4,5,6)P(5) and InsP(6) in higher concentrations than those found in mammal erythrocytes and in other more active cells such as macrophages. Our data provide further evidence of the similarity between crocodilian and avian groups and agree with the hypothesis that both groups evolved from a common ancestor. The process by which the function of inositol phosphates changed from that of intracellular signaling to hemoglobin allosteric effector is discussed.     

IL-11 and IL-11Rα immunolocalisation at primate implantation sites supports a role for IL-11 in placentation and fetal development

Embryo implantation, endometrial stromal cell decidualization and formation of a functional placenta are critical processes in the establishment and maintenance of pregnancy. Interleukin (IL)-11 signalling is essential for adequate decidualization in the mouse uterus and IL-11 promotes decidualization in the human. IL-11 action is mediated via binding to the specific IL-11 receptor α (IL-11Rα). The present study examined immunoreactive IL-11 and IL-11Rα in cycling rhesus monkey endometrium, at implantation sites in cynomolgus and rhesus monkeys and in human first trimester decidua and defined distinct spatial and temporal patterns. In cycling rhesus monkey endometrium, IL-11 and IL-11Rα increased in both basalis and functionalis regions during the secretory compared with the proliferative phase, with changing cellular locations in luminal and glandular epithelium and stroma. The patterns were similar overall to those previously described in human endometrium. Differences were seen in immunostaining during implantation in cynomologus and rhesus monkey. In the cynomolgus, very little staining for IL-11 or IL-11Rα was seen in syncytio- and cyto-trophoblast cells in the villi between days 12 and 150 of pregnancy although there was moderate staining in cytotrophoblast in the shell between days 12 and 17 and in subpopulations of cytotrophoblast cells invading the arteries at day 17. By contrast in the rhesus monkey between days 24 and 35 of pregnancy and in human first trimester placenta, cyto- and syncytio-trophoblast in the villi but not cytotrophoblast in the shell were positively stained. The most intense staining for both IL-11 and IL-11Rα was present within the decidua in the maternal component of implantation sites in all three primates but moderate staining was also present in maternal vascular smooth muscle and glands perivascular cells and epithelial plaques. These results are consistent with a role for IL-11 both during decidualization and placentation in primates.     

D4 Dopamine and Metabotropic Glutamate Receptors in Cerebral Cortex and Striatum in Rat Brain

The characterization of the functional interactions between the metabotropic glutamate receptors (mGluR) and the dopaminergic (DR) receptors in the corticostriatal projections may provide a possible interpretation of synaptic events in the basal ganglia. It has been suggested that presynaptic D2-type receptor located on glutamatergic corticostriatal neurons regulates the release of glutamate. In a first approach we have studied the cellular distribution of the D4R and the mGluRs in cerebral cortex and striatum employing immunocytochemistry. D4R positive neurons were particularly numerous in medial prefrontal cortex mainly occupying layers II and III. An even distribution was found on small round-shaped neurons in the striatum. Group I mGluR1-like immunoreactivity (mGluR1-LI) was found in medial and deep layers of the cerebral cortex while group III mGluR4a labeled more superficial layers; group II mGluR2/3 signal was intense on fine fibers with a punctate appearance. In the striatum, mGluR1 and mGluR2/3 stained mainly fibers while mGluR4a labeled round shaped cell bodies. After lateral ventricular injection of colchicine, an axonal transport and firing activity blocker, D4R labeling significantly increased in cerebral cortex and decreased in the striatum. mGluR1 and mGluR4a signal decreased in cerebral cortex and only mGluR4a signal decreased in the striatum. These results support previous reports indicating a presynaptic localization of D4R in the striatum. In contrast, striatal mGluR1 appears to be a postsynaptic receptor probably synthesized in situ. Our results do not support the hypothesis of a colocalization of D4 receptor and one or more of the metabotropic glutamatergic receptors studied here.     

Mitochondrial DNA variability in the Canary Islands honeybees (Apis mellifera L.)

The mitochondrial DNA (mtDNA) of individuals from 79 colonies of Apis mellifera from five Canary Islands was studied using the Dra I test based on the restriction of PCR products of the tRNAleu–COII intergenic region. Five haplotypes of the African (A) lineage and one of the west European (C) lineage were found. The haplotypes A14 and A15 are described for the first time. These haplotypes have a new P sequence named P₁. The wide distribution and high frequency of haplotype A15 suggest that it is characteristic of the Canarian Archipelago. Sources of haplotype variability of honeybee mtDNA in the Canary Islands (waves of colonization from Africa, queen importations, habitat diversification) are discussed.     

Selective activity against Mycobacterium tuberculosis of new quinoxaline 1,4-di-N-oxides

New series of 3-phenylquinoxaline 1,4-di-N-oxide with selective activity against Mycobacterium tuberculosis have been prepared and evaluated. Thirty-four of the seventy tested compounds showed an MIC value less than 0.2 μg/mL, a value on the order of the MIC of rifampicin. Furthermore, 45% of the evaluated derivatives showed a good in vitro activity/toxicity ratio. The most active and selective compounds carry a fluorine atom in the quinoxaline 7-position or in the phenyl substituent para-position. In conclusion, the potency, low cytotoxicity and selectivity of these compounds make them valid lead compounds for synthesizing new analogues, particularly compound 7-methyl-3-(4’-fluoro)phenylquinoxaline-2-carbonitrile 1,4-di-N-oxide (MIC <0.2 μg/mL and SI >500).     

Outcome of Arthroscopy in Patients with Advanced Osteoarthritis of the Hip

Hip arthroscopy has continued to expand its horizons in treating many conditions other than femoroacetabular impingement (FAI). However, the results of hip arthroscopy are known to be poor if the degree of articular cartilage damage is significant. We wanted to assess, whether the procedure might have a role in the management of young and active patients with advanced osteoarthritis (OA) and whether it should be offered as a treatment modality. 77 consecutive patients with Tönnis grade 2 and 3 osteoarthritis of the hip who had undergone hip arthroscopy were included in the study. Patients'' medical notes, plain radiographs and outcome scores (modified Harris hip score (mHHS), non-arthritic hip score (NAHS)) preoperatively and postoperatively at six weeks, six months, one year and annually thereafter, were analysed. 77 patients consisted of 63 men and 14 women with mean follow-up of 2.8 years (2.2 to 4.2) and mean age at surgery of 43 years (19 to 64). The mean preoperative mHHS and NAHS scores were 58 (28 to 87) and 64 (27 to 93) respectively. The mean improvements in both the mHHS and NAHS scores were significant (p = 0.003 and p = 0.0001 for mHHS at one and two years, p = 0.002 and p = 0.0003 for NAHS at one and two years, respectively). There were 34 patients (44%) who required a total hip replacement at mean of 18 months (6 to 48) after hip arthroscopy. We conclude that hip arthroscopy improves outcome scores in 56% of patients with severe OA of the hip (Tönnis grade 2 and 3) for at least two years after surgery. We thus consider the procedure to be a reasonable option for patients with hip OA, although success of the procedure will be less than if undertaken for certain other conditions.