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931.
Giordani RB Junior CO de Andrade JP Bastida J Zuanazzi JA Tasca T de Almeida MV 《Chemical biology & drug design》2012,80(1):129-133
Six lycorine derivatives were prepared, characterized, and evaluated for their in vitro anti‐Trichomonas vaginalis activity. Compounds bearing an acetyl ( 2 ), lauroyl ( 3 ), benzoyl ( 4 and 5 ), and p‐nitrobenzoyl ( 6 and 7 ) groups were synthesized. The best activity was achieved with lycorine esterified at C‐2 position with lauroyl group. Preliminary structure–activity relationship points that unprotected OH group at C‐1 and C‐2 is not necessary to the antiparasitic activity, and none of the derivative was less active than lycorine. The lycorine structural requisites required to kill this amitochondriate cell seem to be different in comparison with the derivatives most active against other parasites and tumor cell lines, both mitochondriated cells. This result is an important contribution with our ongoing studies regarding the mechanism of action of the Amaryllidaceae alkaloids on T. vaginalis cell death opening a new perspective to optimize this innovative pharmacological potential. 相似文献
932.
Franco LL de Almeida MV E Silva LF Vieira PP Pohlit AM Valle MS 《Chemical biology & drug design》2012,79(5):790-797
Dihydroperoxides and tetraoxanes derived from symmetrically substituted bis(arylmethyl)acetones were synthesized in modest to good yields using several methods. Three of these compounds exhibit an important in vitro antimalarial activity (1.0 μm ≤ IC50 ≤ 5.0 μm ) against blood forms of the human malaria parasite Plasmodium falciparum. 相似文献
933.
The study assesses the role and impact of nursing in an ongoing trial of integrated primary cares, carried out in a health district in northern Italy, started in 2004. The goals were to establish a joint collaboration with general practitioners (GP), in order to improve the follow-up of chronic patients. As a first stage, the trial focuses on COPD (chronic obstructive pulmonary disease), diabetes mellitus, hypertension, cardiovascular failure and patients following anticoagulant therapy. The district??s project covers up to 60,000 patients treated by the team of GPs and nurses. Benefits for users are represented by easier access to cares, dedicated projects for chronic disease, follow-up, health education and multidisciplinary work. This first reports presents the questionnaire data according to patients?? satisfaction and the results achieved so far on COPD patients: 101.6% of COPD patients followed by teams have had at least 1 spirometry/year (vs. 43.2% of all the COPD affected??regional data) Hospital admissions are lower according to people attending a COPD integrated program and it is getting lower in time (health district??s rate: 0.125% in 2005?C0.115% in 2007; regional data). 相似文献
934.
Ferrando S Gallus L Gambardella C Amaroli A Vallarino M Tagliafierro G 《Neuroscience letters》2011,499(2):127-131
In vertebrates, the receptor neurons of the olfactory/vomeronasal systems express different receptor gene families and related G-protein types (in particular the G protein alpha subunit). There are no data in the literature about the molecular features of the olfactory/vomeronasal systems of Cladistia thus, in this work, the presence and distribution of different types of G protein alpha subunits were investigated in the olfactory organs of the bichir Polypterus senegalus, using immunohistochemistry. Gαo-like immunoreactivity was detected in the microvillous receptor neurons, with the cell body in the basal zone of the sensory epithelium, and in the crypt neurons. Gαo-like ir glomeruli were mainly localized in the anterior part of the olfactory bulb. Gαolf-like immunoreactivity in the sensory epithelium was detected in the ciliated receptor neurons, while the immunoreactive glomeruli in the olfactory bulb were mainly localized in the ventral-posterior part. No Gαq nor Gαi3 immunoreactivity was detected. These data are partially in agreement with studies that show the distribution of G protein alpha subunits in teleosts, allowing to hypothesize a common organization of the olfactory/vomeronasal systems in the group of Actinopterigians. 相似文献
935.
Mazieres S Callegari-Jacques SM Crossetti SG Dugoujon JM Larrouy G Bois E Crubezy E Hutz MH Salzano FM 《Annals of human biology》2011,38(1):76-83
Background: Previous investigations of French Guiana Amerindians performed by this group included blood group and protein genetic markers, mitochondrial DNA and Y-chromosome investigations. Molecular autosomal data and more extensive Y-chromosome determinations were lacking. Subjects and methods: The genetic variability of 15 autosome (ASTRs) and 17 Y-chromosome (YSTRs) microsatellite loci was studied in four French Guiana (Emerillon, Palikur, Wayampi, Kali'na) and one Brazilian (Apalai) Amerindian populations. A sixth group, the Peruvian Matsiguenga of the Maipurean linguistic family, was included in the data analysis since they could provide information about the past migration of people from that linguistic stock into northeastern Amazonia. Results: Marked ASTR and YSTR variability was found, with 96% of the YSTR haplotypes being found in one population only. There was excellent agreement between the present and previous autosomal or uniparental results. Multidimensional scaling based on F(ST) genetic distances and population structure analysis revealed heterogeneity in gene distribution, with a clear difference between the Matsiguenga and Emerillon and the other groups. In the latter, Wilcoxon sign-rank test between observed and expected heterozygosity and the mode of allele frequency distribution revealed clues of a significant past genetic bottleneck. The Wayampi stand genetically closer to the Apalai, Palikur and Kali'na when examined for the autosome but not the Y-chromosome panel of markers, suggesting preferential female gene flow. Conclusion: The new data provided additional important information about the biological history of people from a remote South American region, indicating how gene diversity analyses can be used to increase understanding of human microevolutionary processes. 相似文献
936.
Fabrizi F Viganò M Banfi G Martin P Messa P Lampertico P 《The International journal of artificial organs》2011,34(10):1031-1035
Hepatitis B virus (HBV) infection persists among patients with renal insufficiency in the industrialized world. A variety of therapeutic options are now available for the treatment of chronic hepatitis B infection, including potent new nucleos(t)ide analogs, along with standard and pegylated interferon. We report on a patient with aggressive hepatitis B and renal insufficiency who was successfully treated with nucleoside analogs (mostly entecavir monotherapy) for two years. He received intense immunosuppression for severe myopathy of lower limbs, probably related to vasculitis. HBV DNA (at the beginning, > 1 x 10(8) IU/mL) was no longer detectable in serum after a few months of antiviral therapy, while HBeAg and HBsAg seroconversion occurred with ALT normalization. Clinical signs of vasculitis disappeared. Five months after discontinuation of entecavir therapy, he remained HBsAg negative with detectable anti-HBs antibody in serum. We conclude that nucleos(t)ide analogs can offer excellent response in selected patients with renal insufficiency and hepatitis B-related liver disease. Prospective, controlled clinical trials are needed to confirm these encouraging results. 相似文献
937.
Locatelli M Caroli M Pluderi M Motta F Gaini SM Tschabitscher M Scarone P 《Surgical and radiologic anatomy : SRA》2011,33(3):257-262
Purpose
The endoscopic transnasal, transsphenoidal approach is considered by many a valid option to reach the sellar region and, in selected cases, to decompress the optic nerve. However, few data are available in literature about the real effectiveness of the procedure and the extent of nerve decompression needed to obtain a clinical result. The aim of this anatomical study was to describe the most important landmarks of the endoscopic transsphenoidal approach to the optic nerve. 相似文献938.
Vieth M Quirke P Lambert R von Karsa L Risio M 《Virchows Archiv : an international journal of pathology》2011,458(1):21-30
Multidisciplinary, evidence-based European Guidelines for quality assurance in colorectal cancer screening and diagnosis have
recently been developed by experts in a pan-European project coordinated by the International Agency for Research on Cancer.
The full guideline document includes a chapter on pathology with pan-European recommendations which take into account the
diversity and heterogeneity of health care systems across the EU. The present paper is based on the annex to the pathology
chapter which attempts to describe in greater depth some of the issues raised in the chapter in greater depth, particularly
details of special interest to pathologists. It is presented here to make the relevant discussion known to a wider scientific
audience. 相似文献
939.
Quality assurance in pathology in colorectal cancer screening and diagnosis—European recommendations
Quirke P Risio M Lambert R von Karsa L Vieth M 《Virchows Archiv : an international journal of pathology》2011,458(1):1-19
In Europe, colorectal cancer is the most common newly diagnosed cancer and the second most common cause of cancer deaths,
accounting for approximately 436,000 incident cases and 212,000 deaths in 2008. The potential of high-quality screening to
improve control of the disease has been recognized by the Council of the European Union who issued a recommendation on cancer
screening in 2003. Multidisciplinary, evidence-based European Guidelines for quality assurance in colorectal cancer screening
and diagnosis have recently been developed by experts in a pan-European project coordinated by the International Agency for
Research on Cancer. The full guideline document consists of ten chapters and an extensive evidence base. The content of the
chapter dealing with pathology in colorectal cancer screening and diagnosis is presented here in order to promote international
discussion and collaboration leading to improvements in colorectal cancer screening and diagnosis by making the principles
and standards recommended in the new EU Guidelines known to a wider scientific community. 相似文献
940.
Species of the genus Culex Linnaeus have been incriminated as the main vectors of lymphatic filariases and are important vectors of arboviruses, including West Nile virus. Sequences corresponding to a fragment of 478 bp of the cytochrome c oxidase subunit I gene, which includes part of the barcode region, of 37 individuals of 17 species of genus Culex were generated to establish relationships among five subgenera, Culex, Phenacomyia, Melanoconion, Microculex, and Carrollia, and one species of the genus Lutzia that occurs in Brazil. Bayesian methods were employed for the phylogenetic analyses. Results of sequence comparisons showed that individuals identified as Culex dolosus, Culex mollis, and Culex imitator possess high intraspecific divergence (3.1, 2.3, and 3.5%, respectively) when using the Kimura two parameters model. These differences were associated either with distinct morphological characteristics of the male genitalia or larval and pupal stages, suggesting that these may represent species complexes. The Bayesian topology suggested that the genus and subgenus Culex are paraphyletic relative to Lutzia and Phenacomyia, respectively. The cytochrome c oxidase subunit I sequences may be a useful tool to both estimate phylogenetic relationships and identify morphologically similar species of the genus Culex. 相似文献