Anopheles darlingi polytene chromosomes: revised maps including newly described inversions and evidence for population structure in Manaus

Salivary gland polytene chromosomes of 4th instar Anopheles darlingi Root were examined from multiple locations in the Brazilian Amazon. Minor modifications were made to existing polytene photomaps. These included changes to the breakpoint positions of several previously described paracentric inversions and descriptions of four new paracentric inversions, two on the right arm of chromosome 3 and two on the left arm of chromosome 3 that were found in multiple locations. A total of 18 inversions on the X (n = 1) chromosome, chromosome 2 (n = 7) and 3 (n = 11) were scored for 83 individuals from Manaus, Macapá and Porto Velho municipalities. The frequency of 2Ra inversion karyotypes in Manaus shows significant deficiency of heterozygotes (p < 0.0009). No significant linkage disequilibrium was found between inversions on chromosome 2 and 3. We hypothesize that at least two sympatric subpopulations exist within the An. darlingi population at Manaus based on inversion frequencies.

Evaluation of the efficacy and safety of lanreotide in combination with targeted therapies in patients with neuroendocrine tumours in clinical practice: a retrospective cross-sectional analysis.

BACKGROUND Based on the mechanism of action, combining somatostatin analogues (SSAs) with mTOR inhibitors or antiangiogenic agents may provide synergistic effects for the treatment of patients with neuroendocrine tumours (NETs). Herein, we investigate the use of these treatment combinations in clinical practice. METHODS This retrospective cross-sectional analysis of patients with NETs treated with the SSA lanreotide and targeted therapies at 35 Spanish hospitals evaluated the efficacy and safety of lanreotide treatment combinations in clinical practice. The data of 159 treatment combinations with lanreotide in 133 patients was retrospectively collected. RESULTS Of the 133 patients, with a median age of 59.4 (16-83) years, 70 (52.6 %) patients were male, 64 (48.1 %) had pancreatic NET, 23 (17.3 %) had ECOG PS ≥2, 41 (30.8 %) had functioning tumours, 63 (47.7 %) underwent surgery of the primary tumour, 45 (33.8 %) had received prior chemotherapy, and 115 (86.5 %) had received prior SSAs. 115 patients received 1 lanreotide treatment combination and 18 patients received between 2 and 5 combinations. Lanreotide was mainly administered in combination with everolimus (73 combinations) or sunitinib (61 combinations). The probability of being progression-free was 78.5 % (6 months), 68.6 % (12 months) and 57.0 % (18 months) for patients who only received everolimus plus lanreotide (n = 57) and 89.3 % (6 months), 73.0 % (12 months), and 67.4 % (18 months) for patients who only received sunitinib and lanreotide (n = 50). In patients who only received everolimus plus lanreotide the median time-to-progression from the initiation of lanreotide combination treatment was 25.8 months (95 % CI, 11.3, 40.3) and it had not yet been reached among the subgroup of patients only receiving sunitinib plus lanreotide. The safety profile of the combination treatment was comparable to that of the targeted agent alone. CONCLUSIONS The combination of lanreotide and targeted therapies, mainly everolimus and sunitinib, is widely used in clinical practice without unexpected toxicities and suggests efficacy that should be explored in randomized prospective clinical trials.

Role of CCR5 genetic polymorphisms in clinical and histological outcomes of hepatitis C

Background: The CCR5 32-base deletion (CCR5D32), which results into the expression of a non-functioning receptor, has been associated with H CV c learance a nd may influence fibrosis progression i n hepatitis C . We a ssessed t he link between C CR5D32 and c linical outcomes o f HCV. Methods: Genomic D NA was isolated and analyzed b y PCR to i dentify C CR5D32 in 1 303 anti-HCV-positive persons (161 clearers and 1142 chronically infected, 1007 with a liver biopsy). Results: Overall, 200 (15.3%) w ere heterozygote a nd 16 (1.2%) homozygote for CCR5D32. H CV c learance (by univariate) was associated with m ale sex (OR 0.633, 9 5% C I 0.428-0.935, P=0.022), HCV acquisition by blood transfusion (OR 0.360, 95% CI 0.175-0.741, P =0.0056), polymorphisms at IL28B rs12979860 ( OR 0.482, 9 5% C I 0.277-0.839, P =0.0098) a nd rs8099917 ( OR 0.291, 95% CI 0.167-0.508, P=0.000014), but not with CCR5D32. However, CCR5D32 was associated with spontaneous HCV clearance when the 482 females only w ere considered, although the number of homozygotes was small (1/427 chronic vs 3/51 clearers) (OR 24.56, 95% C I 12.5-241.4, P =0.006). T he CCR5D32 deletion was not associated with liver grading and staging scores, fibrosis progression rate, or t herapy response. Conclusions: At v ariance w ith a p revious report (Nattermann et a l, 2011), suggesting that a n on-functional CCR5 m ay hamper H CV clearance, C CR5D32 appeared to b e associated with an increased spontaneous eradication in women (but not men). Given the small number of CCR5D32 homozygote persons, these data need further validation.

Prognosis Relevance of Serum Cytokines in Pancreatic Cancer.

The overall survival of patients with pancreatic ductal adenocarcinoma is extremely low. Although gemcitabine is the standard used chemotherapy for this disease, clinical outcomes do not reflect significant improvements, not even when combined with adjuvant treatments. There is an urgent need for prognosis markers to be found. The aim of this study was to analyze the potential value of serum cytokines to find a profile that can predict the clinical outcome in patients with pancreatic cancer and to establish a practical prognosis index that significantly predicts patients' outcomes. We have conducted an extensive analysis of serum prognosis biomarkers using an antibody array comprising 507 human cytokines. Overall survival was estimated using the Kaplan-Meier method. Univariate and multivariate Cox's proportional hazard models were used to analyze prognosis factors. To determine the extent that survival could be predicted based on this index, we used the leave-one-out cross-validation model. The multivariate model showed a better performance and it could represent a novel panel of serum cytokines that correlates to poor prognosis in pancreatic cancer. B7-1/CD80, EG-VEGF/PK1, IL-29, NRG1-beta1/HRG1-beta1, and PD-ECGF expressions portend a poor prognosis for patients with pancreatic cancer and these cytokines could represent novel therapeutic targets for this disease.

Interactions between feather-degrading bacteria and an avian host : zebra finches (Taeniopygia guttata)

Abstract: Birds harbor a variety of bacteria on their plumage, some of which can degrade feathers in vitro. Whether these keratinolytic bacteria are active on live birds and can effect feather degradation on birds is debatable. The effect of such bacteria on the body condition and behavior of birds, is unknown. Using a community of feather-degrading bacteria (EB), we investigate the interaction between the activity and load of such bacteria, on the morphology, body condition, and behavior of zebra finches (Taeniopygia guttata). In Chapter 2, we find that the elevated loads of such microbes lead to a reduction in the expression of morphological traits, such as male bill color (a sexually selected trait) and uropygial gland volume, without reducing body mass, or evoking a cellular immune response. We also suggest the presence of a carotenoid based defense response in hosts, to such elevated loads of microbes and document a sex-based difference in the source of carotenoids used for such a response. In Chapter 3, we investigated the effect of EB loads on male mate choice of zebra finches, wherein male choice of females with elevated and un-altered bacterial loads, varied with male size. We found that larger males preferred females with higher bacterial load and smaller males preferred females with lower bacterial load. Chapter 4 demonstrates that the presence of melanin in feathers reduces the growth and activity of the community of feather-degrading bacteria (EB) and that the EB community can effect feather degradation in humid conditions, without broth. Additional results also demonstrate that the EB community consists of bacteria that can attach themselves to feathers on live birds and those that can live freely on avian plumage. Finally, chapter 5 demonstrates that the self-maintenance, social and sexual behaviors of birds are implicated in the infection and horizontal transmission of bacteria. It also suggests a linked oral - faecal - genital mode of transmission of pathogens in birds. These results demonstrate that differential loads of normal flora of vertebrate hosts can effect changes in their morphology and behavior. They also shed light on the role of feather-degrading bacteria in the evolution of melanin polymorphism in birds and suggest that bacteria can be active on live birds. This thesis also highlights the importance of social and, sexual behaviors of birds, in epidemiology. Résumé: Les Oiseaux ont dans leur plumage diverses bactéries dont certaines dégradent les plumes in vitro, néanmoins. Il n'est pas clair, au vu de précédentes études, si ces bactéries kératinolytiques sont actives sur des oiseaux vivants, et si celles-ci dégradent effectivement le plumage de leur hôte, L'effet de ces bactéries sur la condition corporelle ainsi que le comportement des oiseaux n'est pas connu. A l'aide d'une communauté de bactéries dégradant les plumes (EB), non pathogènes, nous examinons les interactions entre l'activité et la charge bactérienne sur la morphologie, la condition corporelle et le comportement du diamant mandarins (Taeniopygia guttata). Dans le chapitre 2, nous montrons qu'une charge élevée de ces microbes mène à une réduction de l'expression de certains traits morphologiques, tels que la couleur du bec chez le mâle (un trait soumis à sélection sexuelle), ainsi que le volume de la glande uropygienne, sans qu'il y ait une réduction de la masse corporelle, ni déclenchement d'une réponse immune cellulaire. Nos données suggèrent la présence d'une défense chez l'hôte à des charges élevées de bactéries basée sur la présence de caroténoïdes. Nous montrons, de plus une différence liée au sexe dans la source des caroténoïdes utilisé pour cette réponse. Dans le chapitre 3 nous examinons l'influence de la charge bactérienne EB sur le choix des mâles chez le diamant mandarins. Des femelles avec une charge bactérienne normale et augmentée sont choisies par les mâles et ce choix varie avec la taille des mâles. Nous avons mis en évidence que les grands mâles préfèrent les femelles avec une charge bactérienne plus élevée. Les petits mâles préfèrent les femelles avec une charge bactérienne réduite. Le chapitre 4 démontre que la présence de mélanine dans les plumes réduit la croissance et l'activité de la communauté de bactéries dégradant le plumage (EB), et que cette communauté EB peut dégrader les plumes dans des conditions humides, sans milieu de culture liquide. De plus nous montrons que cette communauté consiste en des bactéries qui peuvent s'attacher sur les plumes d'oiseaux vivants ainsi que des bactéries libres. Pour finir nous montrons dans le chapitre 5 que la maintenance corporelle, l'interaction sociale et le comportement sexuel de ces oiseaux sont impliqués dans l'infection et la transmission horizontale de ces bactéries. Nos données suggèrent une transmission orale-fécale-génitale des pathogènes chez les oiseaux. Ces résultats montrent que des charges différentes de la flore bactérienne habituelle et non pathogène de vertébrés peuvent affecter leur morphologie et leur comportement. Ils éclaircissent également le rôle des bactéries dégradant les plumes dans l'évolution du polymorphisme mélanique chez les oiseaux et suggèrent que ces bactéries peuvent être actives sur des oiseaux vivants. Cette thèse souligne également l'importance du comportement social et sexuel des oiseaux dans l'épidémiologie.

Genome-wide association study identifies variants associated with progression of liver fibrosis from HCV infection.

Polymorphisms in IL28B were shown to affect clearance of hepatitis C virus (HCV) infection in genome-wide association (GWA) studies. Only a fraction of patients with chronic HCV infection develop liver fibrosis, a process that might also be affected by genetic factors. We performed a 2-stage GWA study of liver fibrosis progression related to HCV infection. We studied well-characterized HCV-infected patients of European descent who underwent liver biopsies before treatment. We defined various liver fibrosis phenotypes on the basis of METAVIR scores, with and without taking the duration of HCV infection into account. Our GWA analyses were conducted on a filtered primary cohort of 1161 patients using 780,650 single nucleotide polymorphisms (SNPs). We genotyped 96 SNPs with P values <5 × 10(-5) from an independent replication cohort of 962 patients. We then assessed the most interesting replicated SNPs using DNA samples collected from 219 patients who participated in separate GWA studies of HCV clearance. In the combined cohort of 2342 HCV-infected patients, the SNPs rs16851720 (in the total sample) and rs4374383 (in patients who received blood transfusions) were associated with fibrosis progression (P(combined) = 8.9 × 10(-9) and 1.1 × 10(-9), respectively). The SNP rs16851720 is located within RNF7, which encodes an antioxidant that protects against apoptosis. The SNP rs4374383, together with another replicated SNP, rs9380516 (P(combined) = 5.4 × 10(-7)), were linked to the functionally related genes MERTK and TULP1, which encode factors involved in phagocytosis of apoptotic cells by macrophages. Our GWA study identified several susceptibility loci for HCV-induced liver fibrosis; these were linked to genes that regulate apoptosis. Apoptotic control might therefore be involved in liver fibrosis.

Two waves of recombinase gene expression in developing thymocytes.

During T cell development in the thymus, T cell receptor (TCR) alpha, beta, gamma, and delta genes are rearranged and expressed. TCR rearrangement strictly depends upon the coordinate activity of two recombinase activating genes, Rag-1 and Rag-2. In this study we have followed the expression of these genes at different stages of intrathymic development. The results indicate that there are two periods of high Rag-1 and Rag-2 mRNA expression. The first wave peaks early at the CD25+CD4-CD8-CD3- stage of development and coincides with the initial appearance of transcripts derived from fully rearranged TCR beta, gamma, and delta genes, whereas the second wave occurs later at the CD4+CD8+ stage coincident with full-length TCR alpha mRNA expression. Active downregulation of Rag-1 and Rag-2 mRNA expression appears to occur in vivo between the two peaks of recombinase activity. This phenomenon can be mimicked in vitro in response to artificial stimuli such as phorbol myristate acetate and calcium ionophore. Collectively our data suggest that recombinase expression is actively regulated during early thymus development independently of cell surface expression of a mature heterodimeric TCR protein complex.

Microtubule-associated protein-2 immunoreactivity: a useful tool in the differential diagnosis of low-grade neuroepithelial tumors.

Complex and variable morphological phenotypes pose a major challenge to the histopathological classification of neuroepithelial tumors. This applies in particular for low-grade gliomas and glio-neuronal tumors. Recently, we and others have identified microtubule-associated protein-2 (MAP2) as an immunohistochemical marker expressed in the majority of glial tumors. Characteristic cell morphologies can be recognized by MAP2 immunoreactivity in different glioma entities, i.e., process sparse oligodendroglial versus densely ramified astrocytic elements. Here, we describe MAP2-immunoreactivity patterns in a large series of various neuroepithelial tumors and related neoplasms (n = 960). Immunohistochemical analysis led to the following conclusions: (1) specific pattern of MAP2-positive tumor cells can be identified in 95% of glial neoplasms; (2) ependymal tumors do not express MAP2 in their rosette-forming cell component; (3) tumors of the pineal gland as well as malignant embryonic tumors are also characterized by abundant MAP2 immunoreactivity; (4) virtually no MAP2 expression can be observed in the neoplastic glial component of glio-neuronal tumors, i.e. gangliogliomas; (5) malignant glial tumor variants (WHO grade III or IV) exhibit different and less specific MAP2 staining patterns compared to their benign counterparts (WHO grade I or II); (6) with the exception of melanomas and small cell lung cancers, MAP2 expression is very rare in metastatic and non-neuroepithelial tumors; (7) glial MAP2 expression was not detected in 56 non-neoplastic lesions. These data point towards MAP2 as valuable diagnostic tool for pattern recognition and differential diagnosis of low-grade neuroepithelial tumors.

Developmentally regulated expression of P-glycoprotein (multidrug resistance) activity in mouse thymocytes.

P-glycoprotein (P-gly) is the transmembrane efflux pump responsible for multidrug resistance in tumor cells. The activity of P-gly in mature peripheral lymphocytes is lineage specific, with CD8+ T cells and natural killer (NK) cells expressing high levels as compared to CD4+ T cells and B cells. We have now investigated P-gly activity in immature and mature subsets of mouse thymocytes. Our data indicate that P-gly activity is undetectable in immature CD4-8- and CD4+8+ thymocyte subsets. Among mature thymocytes, P-gly activity is absent in the CD4+ subset but present in the more mature (HSAlow) fraction of CD8+ cells. Furthermore, while thymic CD4-8- T cell receptor (TCR) gamma delta cells have little P-gly activity, a minor subset of CD4-8- or CD4+ TCR alpha beta + thymocytes bearing the NK1.1 surface marker expresses high levels of P-gly activity. Collectively, our results indicate that P-gly activity arises late during thymus development and is expressed in a lineage-specific fashion.

PGE2-induced colon cancer growth is mediated by mTORC1.

The inflammatory prostaglandin E2 (PGE2) cytokine plays a key role in the development of colon cancer. Several studies have shown that PGE2 directly induces the growth of colon cancer cells and furthermore promotes tumor angiogenesis by increasing the production of the vascular endothelial growth factor (VEGF). The signaling intermediaries implicated in these processes have however not been fully characterized. In this report, we show that the mechanistic target of rapamycin complex 1 (mTORC1) plays an important role in PGE2-induced colon cancer cell responses. Indeed, stimulation of LS174T cells with PGE2 increased mTORC1 activity as observed by the augmentation of S6 ribosomal protein phosphorylation, a downstream effector of mTORC1. The PGE2 EP4 receptor was responsible for transducing the signal to mTORC1. Moreover, PGE2 increased colon cancer cell proliferation as well as the growth of colon cancer cell colonies grown in matrigel and blocking mTORC1 by rapamycin or ATP-competitive inhibitors of mTOR abrogated these effects. Similarly, the inhibition of mTORC1 by downregulation of its component raptor using RNA interference blocked PGE2-induced LS174T cell growth. Finally, stimulation of LS174T cells with PGE2 increased VEGF production which was also prevented by mTORC1 inhibition. Taken together, these results show that mTORC1 is an important signaling intermediary in PGE2 mediated colon cancer cell growth and VEGF production. They further support a role for mTORC1 in inflammation induced tumor growth.

Thyroid metastasis as initial presentation of clear cell renal carcinoma.

INTRODUCTION Metastatic tumors account for 1.4-2.5% of thyroid malignancies. About 25-30% of patients with clear cell renal carcinoma (CCRC) have distant metastasis at the time of diagnosis, being the thyroid gland a rare localization [5%]. PRESENTATION OF THE CASE A 62-year woman who underwent a cervical ultrasonography and a PAAF biopsy reporting atypical follicular proliferation with a few intranuclear vacuoles "suggestive" of thyroid papillary cancer in the context of a multinodular goiter was reported. A total thyroidectomy was performed and the histology of a clear cell renal carcinoma (CCRC) was described in four nodules of the thyroid gland. A CT scan was performed and a renal giant right tumor was found. The patient underwent an eventful radical right nephrectomy and the diagnosis of CCRC was confirmed. DISCUSSION Thyroid metastasis (TM) from CCRC are usually apparent in a metachronic context during the follow-up of a treated primary (even many years after) but may sometimes be present at the same time than the primary renal tumor. Our case is exceptional because the TM was the first evidence of the CCRC, which was subsequently diagnosed and treated. CONCLUSION The possibility of finding of an incidental metastatic tumor in the thyroid gland from a previous unknown and non-diganosed primary (as CCRC in our case was) is rare and account only for less than 1% of malignancies. Nonetheless, the thyroid gland is a frequent site of metastasis and the presence of "de novo" thyroid nodules in oncologic patients must be always considered and studied.

Genotype 3 is associated with accelerated fibrosis progression in chronic hepatitis C.

BACKGROUND/AIMS: While several risk factors for the histological progression of chronic hepatitis C have been identified, the contribution of HCV genotypes to liver fibrosis evolution remains controversial. The aim of this study was to assess independent predictors for fibrosis progression. METHODS: We identified 1189 patients from the Swiss Hepatitis C Cohort database with at least one biopsy prior to antiviral treatment and assessable date of infection. Stage-constant fibrosis progression rate was assessed using the ratio of fibrosis Metavir score to duration of infection. Stage-specific fibrosis progression rates were obtained using a Markov model. Risk factors were assessed by univariate and multivariate regression models. RESULTS: Independent risk factors for accelerated stage-constant fibrosis progression (>0.083 fibrosis units/year) included male sex (OR=1.60, [95% CI 1.21-2.12], P<0.001), age at infection (OR=1.08, [1.06-1.09], P<0.001), histological activity (OR=2.03, [1.54-2.68], P<0.001) and genotype 3 (OR=1.89, [1.37-2.61], P<0.001). Slower progression rates were observed in patients infected by blood transfusion (P=0.02) and invasive procedures or needle stick (P=0.03), compared to those infected by intravenous drug use. Maximum likelihood estimates (95% CI) of stage-specific progression rates (fibrosis units/year) for genotype 3 versus the other genotypes were: F0-->F1: 0.126 (0.106-0.145) versus 0.091 (0.083-0.100), F1-->F2: 0.099 (0.080-0.117) versus 0.065 (0.058-0.073), F2-->F3: 0.077 (0.058-0.096) versus 0.068 (0.057-0.080) and F3-->F4: 0.171 (0.106-0.236) versus 0.112 (0.083-0.142, overall P<0.001). CONCLUSIONS: This study shows a significant association of genotype 3 with accelerated fibrosis using both stage-constant and stage-specific estimates of fibrosis progression rates. This observation may have important consequences for the management of patients infected with this genotype.

Delta-like 4 is the essential, nonredundant ligand for Notch1 during thymic T cell lineage commitment.

Thymic T cell lineage commitment is dependent on Notch1 (N1) receptor-mediated signaling. Although the physiological ligands that interact with N1 expressed on thymic precursors are currently unknown, in vitro culture systems point to Delta-like 1 (DL1) and DL4 as prime candidates. Using DL1- and DL4-lacZ reporter knock-in mice and novel monoclonal antibodies to DL1 and DL4, we show that DL4 is expressed on thymic epithelial cells (TECs), whereas DL1 is not detected. The function of DL4 was further explored in vivo by generating mice in which DL4 could be specifically inactivated in TECs or in hematopoietic progenitors. Although loss of DL4 in hematopoietic progenitors did not perturb thymus development, inactivation of DL4 in TECs led to a complete block in T cell development coupled with the ectopic appearance of immature B cells in the thymus. These immature B cells were phenotypically indistinguishable from those developing in the thymus of conditional N1 mutant mice. Collectively, our results demonstrate that DL4 is the essential and nonredundant N1 ligand responsible for T cell lineage commitment. Moreover, they strongly suggest that N1-expressing thymic progenitors interact with DL4-expressing TECs to suppress B lineage potential and to induce the first steps of intrathymic T cell development.

Thyrotropin-releasing hormone-stimulated thyrotropin expression involves islet-brain-1/c-Jun N-terminal kinase interacting protein-1.

Islet-brain-1 (IB1)/c-Jun N-terminal kinase interacting protein 1 (JIP-1) is a scaffold protein that is expressed at high levels in neurons and the endocrine pancreas. IB1/JIP-1 interacts with the c-Jun N-terminal kinase and mediates the specific physiological stimuli (such as cytokines). However, the potential role of the protein in the pituitary has not been evaluated. Herein, we examined expression of the gene encoding IB1/JIP-1 and its translated product in the anterior pituitary gland and a pituitary cell line, GH3. We then examined the potential role of IB1/JIP-1 in controlling TSH-beta gene expression. Exposure of GH3 cells to TRH stimulated the expression of IB1/JIP-1 protein levels, mRNA, and transcription of the promoter. The increase of IB1/JIP-1 content by transient transfection study of a vector encoding IB1/JIP-1 or by the stimulation of TRH stimulates TSH-beta promoter activity. This effect is not found in the presence of a mutated nonfunctional (IB1S59N) IB1/JIP-1 protein. Together, these facts point to a central role of the IB1/JIP-1 protein in the control of TRH-mediated TSH-beta stimulation.