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Póvoa e Meadas, Portugal

Smith K.R.,Walter and Eliza Hall Institute of Medical Research | Smith K.R.,University of Melbourne | Damiano J.,University of Melbourne | Franceschetti S.,Carlo Besta Neurological Institute | And 13 more authors.
American Journal of Human Genetics | Year: 2012

We performed hypothesis-free linkage analysis and exome sequencing in a family with two siblings who had neuronal ceroid lipofuscinosis (NCL). Two linkage peaks with maximum LOD scores of 3.07 and 2.97 were found on chromosomes 7 and 17, respectively. Unexpectedly, we found these siblings to be homozygous for a c.813-816del (p.Thr272Serfs10) mutation in the progranulin gene (GRN, granulin precursor) in the latter peak. Heterozygous mutations in GRN are a major cause of frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP), the second most common early-onset dementia. Reexamination of progranulin-deficient mice revealed rectilinear profiles typical of NCL. The age-at-onset and neuropathology of FTLD-TDP and NCL are markedly different. Our findings reveal an unanticipated link between a rare and a common neurological disorder and illustrate pleiotropic effects of a mutation in the heterozygous or homozygous states. © 2012 by The American Society of Human Genetics. All rights reserved. Source

Parreira R.,New University of Lisbon | Cook S.,Natural History Museum in London | Lopes A.,New University of Lisbon | de Matos A.P.,Servico de Anatomia Patologica | And 3 more authors.
Virus Research | Year: 2012

We describe the full genetic characterization of an insect-specific flavivirus (ISF) from Culex theileri (Theobald) mosquitoes collected in Portugal. This represents the first isolation and full characterization of an ISF from Portuguese mosquitoes. The virus, designated CTFV, for Culex theileri flavivirus, was isolated in the C6/36 Stegomyia albopicta (=Aedes albopictus) cell line, and failed to replicate in vertebrate (Vero) cells in common with other ISFs. The CTFV genome encodes a single polyprotein with 3357 residues showing all the features expected for those of flaviviruses. Phylogenetic analyses based on all ISF sequences available to date, place CTFV among Culex-associated flaviviruses, grouping with recently published NS5 partial sequences documented from mosquitoes collected in the Iberian Peninsula, and with Quang Binh virus (isolated in Vietnam) as a close relative. No CTFV sequences were found integrated in their host's genome using a range of specific PCR primers designed to the prM/E, NS3, and NS5 region. © 2012 Elsevier B.V. Source

Anselmo J.,Servico de Endocrinologia e Nutricao | Medeiros S.,Servico de Dermatologia | Carneiro V.,Servico de Anatomia Patologica | Greene E.,U.S. National Institutes of Health | And 6 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2012

Context: Most tumors in Carney complex (CNC) are benign, including primary pigmented nodular adrenocortical disease (PPNAD), the main endocrine tumor in CNC. Adrenocortical cancer (AC) has never been observed in the syndrome. Herein,wedescribe a large Azorean family with CNC caused by a point mutation in the PRKAR1A gene coding for type 1-α (RIα) regulatory subunit of the cAMP-dependent protein kinase A, in which the index patient presented with AC. Objective: We studied the genotype-phenotype correlation in CNC. Design and Setting: We reported on case series and in vitro testing of the PRKAR1A mutation in a tertiary care referral center. Patients: Twenty-two members of a family were investigated for Cushing syndrome and other CNC components; their DNA was sequenced for PRKAR1A mutations. Results: Cushing syndrome due to PPNAD occurred in four patients, including the proposita who presented with AC and three who had Cushing syndrome and/or PPNAD. Lentigines were found in six additional patients who did not have PPNAD. A base substitution (c.439A>G/p.S147G) in PRKAR1A was identified in the proposita, in the three others with PPNAD, in the proposita's twin daughters who had lentigines but no evidence of hypercortisolism, and in five other family members, including one without lentigines or evidence of hypercortisolism. Unlike in other RIα defects, loss of heterozygosity was not observed in AC. The S147G mutation was compared to other expressed PRKAR1A mutations; it led to decreased cAMP and catalytic subunit binding by RIα and increased protein kinase A activity in vitro. Conclusions: In a large family with CNC, one amino acid substitution caused a spectrum of adrenal disease that ranged from lack of manifestations to cancer. PPNAD and AC were the only manifestations of CNC in these patients, in addition to lentigines. These data have implications for counseling patients with CNC and are significant in documenting the first case of AC in the context of PPNAD. Copyright © 2012 by The Endocrine Society. Source

Yamaguti D.C.C.,Servico de Anatomia Patologica | Patricio F.R.D.S.,University of Sao Paulo
European Journal of Gastroenterology and Hepatology | Year: 2011

BACKGROUND: Extrahepatic biliary atresia results from a progressive destruction of the bile ducts by an inflammatory fibrosing process which leads ultimately to cirrhosis of biliary type. The etiology of the disorder remains unknown. The histological features include cholestasis, ductular proliferation, eventual loss of intrahepatic bile ducts, and ducts with primitive embryonic shape (ductal plate malformation). PURPOSE: To examine the morphological changes of the biliary intrahepatic ducts, we aimed at investigating the cell proliferation and the diameter of the interlobular bile ducts in extrahepatic biliary atresia, and in normal liver children. METHODS: Liver samples from 35 patients with biliary atresia and 10 from control normal children were used. Immunoexpression of cytokeratin 19 was evaluated and a double-staining procedure was performed with cytokeratin 8/proliferating cell nuclear antigen. The stereological measurements of the intrahepatic bile ducts diameter were evaluated by a computerized system of image analysis. RESULTS: The patterns of intrahepatic cholangiopathy in biliary atresia were obstructive features (42.86%), paucity of intrahepatic bile ducts (20%), ductal plate malformation (28.57%), and ductal plate malformation associated with paucity of intrahepatic bile ducts (8.57%). The average external diameter of interlobular bile ducts in biliary atresia was smaller than that of the control infant livers. Among the four patterns of biliary atresia cholangiopathies, those associated with ductopenia showed the smallest bile duct diameter. There was a negative correlation between the bile duct to portal space ratio and the age of the child at the time of Kasai portoenterostomy. Only in biliary atresia are the bile duct cells stained with proliferating cell nuclear antigen. CONCLUSION: (i) In biliary atresia, both ductular metaplasia and ductular proliferation were observed; (ii) biliary atresia associated with ductopenia showed narrowing of interlobular ducts, probably as a consequence of degeneration with atrophy and fibrosis. © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Source

Martins M.,University of Algarve | Faleiro M.L.,University of Algarve | da Costa A.M.R.,University of Algarve | Chaves S.,University of Lisbon | And 3 more authors.
Journal of Hazardous Materials | Year: 2010

The mechanism of uranium (VI) removal by two anaerobic bacterial consortia, recovered from an uncontaminated site (consortium A) and other from an uranium mine (consortium U), was investigated. The highest efficiency of U (VI) removal by both consortia (97%) occurred at room temperature and at pH 7.2. Furthermore, it was found that U (VI) removal by consortium A occurred by enzymatic reduction and bioaccumulation, while the enzymatic process was the only mechanism involved in metal removal by consortium U. FTIR analysis suggested that after U (VI) reduction, U (IV) could be bound to carboxyl, phosphate and amide groups of bacterial cells. Phylogenetic analysis of 16S rRNA showed that community A was mainly composed by bacteria closely related to Sporotalea genus and Rhodocyclaceae family, while community U was mainly composed by bacteria related to Clostridium genus and Rhodocyclaceae family. © 2010 Elsevier B.V. Source

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