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1.
Angiogenesis ; 26(3): 365-384, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36631598

RESUMO

The Feline Leukemia Virus Subgroup C Receptor 1a (FLVCR1a) is a transmembrane heme exporter essential for embryonic vascular development. However, the exact role of FLVCR1a during blood vessel development remains largely undefined. Here, we show that FLVCR1a is highly expressed in angiogenic endothelial cells (ECs) compared to quiescent ECs. Consistently, ECs lacking FLVCR1a give rise to structurally and functionally abnormal vascular networks in multiple models of developmental and pathologic angiogenesis. Firstly, zebrafish embryos without FLVCR1a displayed defective intersegmental vessels formation. Furthermore, endothelial-specific Flvcr1a targeting in mice led to a reduced radial expansion of the retinal vasculature associated to decreased EC proliferation. Moreover, Flvcr1a null retinas showed defective vascular organization and loose attachment of pericytes. Finally, adult neo-angiogenesis is severely affected in murine models of tumor angiogenesis. Tumor blood vessels lacking Flvcr1a were disorganized and dysfunctional. Collectively, our results demonstrate the critical role of FLVCR1a as a regulator of developmental and pathological angiogenesis identifying FLVCR1a as a potential therapeutic target in human diseases characterized by aberrant neovascularization.


Assuntos
Células Endoteliais , Neoplasias , Adulto , Animais , Humanos , Camundongos , Células Endoteliais/fisiologia , Neovascularização Patológica/genética , Neovascularização Fisiológica/genética , Peixe-Zebra
2.
Lett Appl Microbiol ; 75(5): 1383-1388, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35971818

RESUMO

The objective of this study is to verify in vitro susceptibility of Pythium insidiosum against the agricultural fungicides mefenoxam and pyraclostrobin and evaluate the toxicity of both compounds. Twenty-one P. insidiosum isolates were tested against mefenoxam and pyraclostrobin using the broth microdilution method. Minimum inhibitory and oomicidal concentrations for both compounds were established. Additionally, scanning electron microscopy was performed on P. insidiosum hyphae treated with the sublethal concentration of each fungicide. The toxicity of the compounds was evaluated in vivo Caenorhabditis elegans model. The concentration to inhibit 100% of P. insidiosum growth ranged from 0·625 to 10 µg ml-1 for mefenoxam and from 0·019 to 5 µg ml-1 for pyraclostrobin. The SEM analysis revealed changes on the surface of the hyphae treated with the fungicides, suggesting possible damage caused by these compounds. There was no evidence of toxicity in vivo models. Mefenoxam and pyraclostrobin did not show toxicity at the doses evaluated and have inhibitory effects on the pathogenic oomycete P. insidiosum. However, further evaluations of their pharmacokinetics and toxicity in different animal species and possible pharmacological interactions are necessary to infer a possible use in the clinical management of pythiosis.


Assuntos
Fungicidas Industriais , Pythium , Animais , Fungicidas Industriais/farmacologia , Testes de Sensibilidade Microbiana
3.
J Endocrinol Invest ; 44(10): 2295-2305, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33730348

RESUMO

INTRODUCTION: Thyrotropin stimulating hormone (TSH) suppression in patients with differentiated thyroid cancer (DTC) aims to decrease the growth and proliferation of thyroid cancer cells. However, the effect of TSH-suppressive therapy on bone microarchitecture remains undefined. METHODS: Cross-sectional study including 43 women with DTC undergoing TSH-suppressive therapy (sTSH) compared to 20 women also on levothyroxine (LT4) therapy but with TSH in the low-normal range (nTSH) since the thyroid surgery. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA), and trabecular bone score (TBS) was evaluated using the TBS iNsigth software. Fracture risk assessed by FRAX, with and without TBS, was calculated. The relationship between suppressive therapy-related parameters and bone parameters was investigated. RESULTS: The TBS mean values were not significantly different in the sTSH and nTSH groups (1.273 ± 0.12 vs 1.307 ± 0.14, p = 0.7197). In both groups, postmenopausal women had degraded microarchitecture (TBS 1.216 ± 0.11 vs 1.213 ± 0.09, p = 0.9333), while premenopausal women had normal microarchitecture (1.328 ± 0.11 vs 1.401 ± 0.12, p = 0.195). The percentage of all postmenopausal women with degraded TBS was 54.7%, while the percentage of osteoporosis diagnoses was 16.1%. The TBS-adjusted FRAX-probability of fracture was similar in sTSH and nTSH groups. Body mass index (BMI) and menopausal status were the only variables associated with TBS and BMD. CONCLUSION: Trabecular microarchitecture assessed by TBS was similar between women on long-term suppressive therapy in DTC and those on LT4 replacement therapy aiming at a TSH level within the low-normal reference range. Low TBS values were observed in postmenopausal women of both groups, suggesting that not only suppressed TSH levels but also a low-normal TSH is associated with deteriorated bone microarchitecture in postmenopausal women following total thyroidectomy.


Assuntos
Adenocarcinoma/tratamento farmacológico , Densidade Óssea , Osso Esponjoso/patologia , Osteoporose/patologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Tireotropina/antagonistas & inibidores , Tiroxina/efeitos adversos , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Osso Esponjoso/efeitos dos fármacos , Estudos Transversais , Feminino , Seguimentos , Humanos , Menopausa , Pessoa de Meia-Idade , Osteoporose/induzido quimicamente , Osteoporose/epidemiologia , Prognóstico , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
4.
J Dairy Sci ; 104(1): 602-615, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33189279

RESUMO

Development of ketosis in high-producing dairy cows contributes to several animal health issues and highlights the need for a better understanding of the genetic basis of metabolic diseases. To evaluate the pattern of differential gene expression in the liver of cows under negative energy balance (NEB), and under subclinical and clinical ketosis, a meta-analysis of gene expression and genome-wide association studies results was performed. An initial systematic review identified 118 articles based on the key words "cow," "liver," "negative energy balance," "ketosis," "expression," "qPCR," "microarray," "proteomic," "RNA-Seq," and "GWAS." After further screening for only peer-reviewed and pertinent articles for gene expression during NEB and clinical and subclinical ketosis (considering plasma levels of ß-hydroxybutyrate), 20 articles were included in the analysis. From the systematic review, 430 significant SNPs identified by genome-wide association studies (GWAS) were assigned to genes reported in gene expression studies by considering chromosome and base pair positions in the ARS-UCD 1.2 bovine assembly. Venn diagrams were created to integrate the data obtained in the systematic review, and Gene Ontology enrichment analysis was carried out using official gene names. A QTL enrichment analysis was also performed to identify potential positional candidate loci. Twenty-four significant SNPs were located within the coordinates of differentially expressed genes located on chromosomes 2, 3, 6, 9, 11, 14, 27, and 29. Three significant metabolic pathways were associated with NEB and subclinical and clinical ketosis. In addition, 2 important genes, PPARA (peroxisome proliferator activated receptor alpha) and ACACA (acetyl-coenzyme A carboxylase α), were identified, which were differentially expressed in the 3 metabolic conditions. The PPARA gene is involved in the regulation of lipid metabolism and fatty liver disease and the ACACA gene encodes an enzyme that catalyzes the carboxylation of acetyl-coenzyme A to malonyl-coenzyme A, which is a rate-limiting step in fatty acid synthesis. Gene network analysis revealed co-expression interactions among 34 genes associated with functions involving fatty acid transport and fatty acid metabolism. For the annotated QTL, 9 QTL were identified for ketosis. The genes FN1 (fibronectin 1) and PTK2 (protein tyrosine kinase 2), which are mainly involved in cell adhesion and formation of extracellular matrix constituents, were enriched for QTL previously associated with the trait "ketosis" on chromosome 2 and for the trait "milk iron content" on chromosome 14, respectively. This integration of gene expression and GWAS data provides an additional understanding of the genetic background of NEB and subclinical and clinical ketosis in dairy cattle. Thus, it is a useful approach to identify biological mechanisms underlying these metabolic conditions in dairy cattle.


Assuntos
Doenças dos Bovinos/genética , Bovinos/genética , Metabolismo Energético , Expressão Gênica , Animais , Doenças dos Bovinos/metabolismo , Feminino
5.
J Assist Reprod Genet ; 38(6): 1589-1600, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33786735

RESUMO

PURPOSE: Cryopreserved ovarian tissue transplant restores ovarian function in young cancer patients after gonadotoxic treatment. However, leukemia is associated with increased risk of malignant cell transmission. We aimed to assess the tumor-inducing potential of two different leukemic cell lines when xenografted to immunodeficient mice. METHODS: Fifty-four female immunodeficient mice were grafted with either 100, 200, 500, 1000, and 10,000 chronic myeloid leukemia in blast crisis (BV-173) cells or relapsed acute lymphoblastic leukemia (RCH-ACV) cells, embedded inside a fibrin scaffold along with 50,000 human ovarian stromal cells. Two mice per cell line received the fibrin matrix without leukemic cells as negative controls. Clinical signs of disease were monitored for 20 weeks. Grafts, liver tissue, and masses were collected for macroscopic analysis and gene expression of BCR-ABL1 and E2A-PBX fusion transcripts present in BV-173 and RCH-ACV respectively. RESULTS: BV-173 cells: Mice grafted with 100, 200, or 500 cells showed no sign of disease after and were negative for BCR-ABL1 expression. Three of the 5 animals grafted with 1000 cells and all mice with 10,000 cells developed disease and showed BCR-ABL1-positive expression. RCH-ACV cells: Two out of 4 mice grafted with 100 cells developed disease and were E2A-PBX1-positive. All the animals grafted with higher cell doses showed signs of disease and all but one were E2A-PBX1-positive. CONCLUSION: The present work proves that the disease-inducing potential of BV-173 and RCH-ACV leukemic cells xenografted to SCID mouse peritoneum differs between cell lines, depending on cell number, type, status, and cytogenetic disease profile when ovarian tissue is harvested.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Folículo Ovariano/transplante , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Transplante Heterólogo , Animais , Linhagem Celular Tumoral , Criopreservação , Modelos Animais de Doenças , Feminino , Preservação da Fertilidade/métodos , Proteínas de Fusão bcr-abl/genética , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Proteínas de Homeodomínio/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Camundongos , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Translocação Genética/genética , Transplantes/crescimento & desenvolvimento , Transplantes/metabolismo
6.
Med Oral Patol Oral Cir Bucal ; 26(6): e815-e824, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34704975

RESUMO

BACKGROUND: Oral cancer represents a worldwide public health problem, being among the most prevalent, associated with high morbidity and mortality rates. This systematic review aimed to review the causes of the delayed diagnosis of oral cancer mainly in the elderly, in developed and developing countries. MATERIAL AND METHODS: Search strategy was developed for MEDLINE databases (via PubMed), EMBASE, Web of Science, SCOPUS, and LILACS and for grey literature (Google Scholar, ProQuest and OpenGrey), without language or period restrictions. The risk of bias was assessed using instruments from the Joanna Briggs Institute and the quality of evidence according to the GRADE system. RESULTS: The search resulted in 14,473 records, of which only 13 met the eligibility criteria. The total sample was 1,705 participants, with a predominance of males. All studies included reported causes of delayed diagnosis of oral cancer related to the patient and five also reported causes related to health professionals. The scarce knowledge of the population was pointed out as the main cause of delayed diagnosis of this cancer. Regarding the risk of bias, ten studies were classified as low risk and three, as moderate risk. The quality of the evidence was very low for the outcome related to delayed diagnosis of oral cancer. CONCLUSIONS: Wide dissemination of information on oral cancer is needed, especially for the elderly, such as its initial signs and symptoms, in developed and developing countries. Further studies should be conducted to better understand the causes of delayed diagnosis of oral cancer in countries with different socioeconomic statuses.


Assuntos
Neoplasias Bucais , Idoso , Humanos , Neoplasias Bucais/diagnóstico
7.
Cytotherapy ; 19(10): 1176-1188, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28801055

RESUMO

BACKGROUND: Obesity is associated with numerous cardiac complications, including arrhythmias, cardiac fibrosis, remodeling and heart failure. Here we evaluated the therapeutic potential of mesenchymal stromal cells (MSCs) and their conditioned medium (CM) to treat cardiac complications in a mouse model of high-fat diet (HFD)-induced obesity. METHODS: After obesity induction and HFD withdrawal, obese mice were treated with MSCs, CM or vehicle. Cardiac function was assessed using electrocardiography, echocardiography and treadmill test. Body weight and biochemical parameters were evaluated. Cardiac tissue was used for real time (RT)-polymerase chain reaction (PCR) and histopathologic analysis. RESULTS/DISCUSSION: Characterization of CM by protein array showed the presence of different cytokines and growth factors, including chemokines, osteopontin, cystatin C, Serpin E1 and Gas 6. HFD-fed mice presented cardiac arrhythmias, altered cardiac gene expression and fibrosis reflected in physical exercise incapacity associated with obesity and diabetes. Administration of MSCs or CM improved arrhythmias and exercise capacity. This functional improvement correlated with normalization of GATA4 gene expression in the hearts of MSC- or CM-treated mice. The gene expression of connexin 43, troponin I, adiponectin, transforming growth factor (TGF) ß, peroxisome proliferator activated receptor gamma (PPARγ), insulin-like growth factor 1 (IGF-1), matrix metalloproteinase-9 (MMP9) and tissue inhibitor of metalloproteinases 1 (TIMP1) were significantly reduced in MSCs, but not in CM-treated mice. Moreover, MSC or CM administration reduced the intensity of cardiac fibrosis. CONCLUSION: Our results suggest that MSCs and CM have a recovery effect on cardiac disturbances due to obesity and corroborate to the paracrine action of MSCs in heart disease models.


Assuntos
Meios de Cultivo Condicionados/farmacologia , Dieta Hiperlipídica/efeitos adversos , Coração/fisiopatologia , Transplante de Células-Tronco Mesenquimais/métodos , Obesidade/fisiopatologia , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/terapia , Citocinas/metabolismo , Fibrose/genética , Fibrose/patologia , Fator de Transcrição GATA4/genética , Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos Endogâmicos BALB C , Miocárdio/patologia , Obesidade/etiologia
8.
Parasite Immunol ; 39(9)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28703913

RESUMO

Helminth infections have the ability to modulate host's immune response through mechanisms that allow the chronic persistence of the worms in the host. Here, we investigated the mechanisms involved on the suppressive effect of Ascaris suum infection using a murine experimental model of LPS-induced inflammation. We found that infection with A. suum markedly inhibited leucocyte influx induced by LPS into air pouches, suppressed secretion of pro-inflammatory cytokines (IL-1ß, TNF-α and IL-6) and induced high levels of IL-10 and TGF-ß. Augmented frequency of CD4+ CD25high Foxp3+ T cells was observed in the mesenteric lymph nodes of infected mice. Adoptive transfer of purified CD4+ CD25+ T cells to recipient uninfected mice demonstrated that these cells were able to induce a suppressive effect in the LPS-induced inflammation in air pouch model. In addition, adoptive transfer of CD4+ CD25+ T cells derived from IL-10 knockout mice suggests that this suppressive effect of A. suum infection involves IL-10 cytokine. In conclusion, our results demonstrated that A. suum experimental infection was capable of suppressing LPS-induced inflammation by mechanisms, which seem to be dependent on responses of CD4+ CD25+ T cells and secretion of IL-10 cytokine.


Assuntos
Ascaríase/imunologia , Ascaris suum/imunologia , Transferência Adotiva , Animais , Ascaríase/parasitologia , Antígenos CD4/metabolismo , Citocinas/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Inflamação/induzido quimicamente , Interleucina-10/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T/imunologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Int J Immunogenet ; 44(1): 27-31, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28032448

RESUMO

This study shows, for the first time, high-resolution allele frequencies of HLA-DQA1 loci in Madeira Island (Portugal) and allows us to better understand and refine present knowledge on DQB1 variation, with the identification of several alleles not previously reported in this population. Estimates on haplotype profile, involving HLA-A, HLA-B, HLA-DRB1, HLA-DQA1 and HLA-DQB1, are also reported.


Assuntos
Frequência do Gene , Variação Genética , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Haplótipos , Alelos , Feminino , Expressão Gênica , Antígenos HLA-A/genética , Antígenos HLA-A/imunologia , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Cadeias alfa de HLA-DQ/imunologia , Cadeias beta de HLA-DQ/imunologia , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Humanos , Masculino , Portugal
10.
Int J Immunogenet ; 44(6): 305-313, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28834219

RESUMO

This study confirms for Madeira Island (Portugal) population the Type 1 Diabetes (T1D) susceptible and protective Human leucocyte antigens (HLA) markers previously reported in other populations and adds some local specificities. Among the strongest T1D HLA associations, stands out, as susceptible, the alleles DRB1*04:05 (OR = 7.3), DQB1*03:02 (OR = 6.1) and DQA1*03:03 (OR = 4.5), as well as the haplotypes DRB1*04:05-DQA1*03:03-DQB1*03:02 (OR = 100.9) and DRB1*04:04-DQA1*03:01-DQB1*03:02 (OR = 22.1), and DQB1*06:02 (OR = 0.07) and DRB1*15:01-DQA1*01:02-DQB1*06:02 (OR = 0.04) as protective. HLA-DQA1 positive for Arginine at position 52 (Arg52) (OR = 15.2) and HLA-DQB1 negative for Aspartic acid at the position 57 (Asp57) (OR = 9.0) alleles appear to be important genetic markers for T1D susceptibility, with higher odds ratio values than any single allele and than most of the haplotypes. Genotypes generated by the association of markers Arg52 DQA1 positive and Asp57 DQB1 negative increase T1D susceptibility much more than one would expected by a simple additive effect of those markers separately (OR = 26.9). This study also confirms an increased risk for DRB1*04/DRB1*03 heterozygote genotypes (OR = 16.8) and also a DRB1*04-DQA1*03:01-DQB1*03:02 haplotype susceptibility dependent on the DRB1*04 allele (DRB1*04:01, OR = 7.9; DRB1*04:02, OR = 3.2; DRB1*04:04, OR = 22.1).


Assuntos
Alelos , Diabetes Mellitus Tipo 1/genética , Haplótipos/genética , Antígenos de Histocompatibilidade Classe II/genética , Feminino , Humanos , Ilhas , Desequilíbrio de Ligação/genética , Masculino , Portugal
11.
Med Oral Patol Oral Cir Bucal ; 22(4): e500-e505, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28624835

RESUMO

BACKGROUND: Mandibular Sagittal Split Osteotomy (MSSO) is a popular technique in orthognathic surgery used both to advance and to retreat the mandible. However, MSSO may incur in important complications, such as bad splits and sensorineural injuries. Knowing the location of the fusion between the buccal and lingual cortical (FBLC) in the mandibular ramus and the bone thickness in the region where osteotomies will be performed is determinant in MSSO planning to avoid complications. The aim of this study was to document and evaluate possible differences between sexes regarding the location of the FBLC in relation to the superior cortical of mandibular foramen (MF) and bone thickness in the region of interest for MSSO in a Brazilian population. MATERIAL AND METHODS: Eighty five cone-beam Computed Tomography (CBCT) scans were used to perform linear measurements to determine the location of the FBLC. Bone thickness from the mandibular canal (MC) to the cortical external surfaces and the diameter of the MC were measured at three different points: mandibular ramus (A), mandibular angle (B) and mesial of the second molar (C). RESULTS: The FBLC was located at a mean distance of 8.3 mm from the superior cortical of the MF in males and 8.1 mm in females. There was no difference between males and females regarding the mean bone thickness from the MC to the buccal external surface at all the points investigated (p>0.05). Bone thickness from the lingual external surface to the MC was bigger among females than males in regions B and C (p < 0.05). The diameter of the MC was bigger among males in regions B and C. CONCLUSION: Sexual dimorphism regarding mandibular bone thickness but not regarding the location of FBLC was present. This fundamental knowledge may assist to the panning of MSSO.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Mandíbula/diagnóstico por imagem , Osteotomia Sagital do Ramo Mandibular , Brasil , Feminino , Humanos , Masculino , Mandíbula/anatomia & histologia , Boca , Caracteres Sexuais , Língua , Adulto Jovem
12.
Eur J Neurosci ; 44(6): 2334-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27421820

RESUMO

Neuroplasticity - the capacity of the brain to change as a response to internal and external pressures - has been studied from a number of different perspectives. Perhaps one of the most powerful models is the study of populations that have been congenitally deprived of a sense. It has been shown that the right Auditory Cortex (AC) of congenitally deaf humans is neuroplastically modified in order to represent visual properties of a stimulus. One unresolved question is how this visual information is routed to the AC of congenitally deaf individuals. Here, we performed volumetric analysis of subcortical auditory and visual brains regions - namely the thalamus (along with three thalamic nuclei: the pulvinar, the lateral geniculate nucleus and the medial geniculate nucleus), and the inferior and superior colliculi - in deaf and hearing participants in order to identify which structures may be responsible for relaying visual information toward the altered AC. Because there is a hemispheric asymmetry in the neuroplastic changes observed in the AC of the congenitally deaf, we reasoned that subcortical structures that also showed a similar asymmetry in their total volume could have been enlisted in the effort of relaying visual information to the neuroplastically altered right AC. We show that for deaf, but not for hearing individuals, the right thalamus, right lateral geniculate nucleus and right inferior colliculus are larger than their left counterparts. These results suggest that these subcortical structures may be responsible for rerouting visual information to the AC in congenital deafness.


Assuntos
Córtex Auditivo/fisiopatologia , Mapeamento Encefálico , Surdez/congênito , Perda Auditiva Neurossensorial/congênito , Humanos , Colículos Superiores/fisiopatologia , Tálamo/fisiopatologia , Córtex Visual/fisiopatologia , Adulto Jovem
13.
J Viral Hepat ; 23(11): 840-849, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26775769

RESUMO

Hepatitis C virus (HCV) NS3 protease inhibitors have been primarily designed against genotype 1, the one with the lowest response to dual therapy. However, less evidence of their efficacy on non-1 genotypes is available, and any such information is mostly concentrated on genotypes 2-4. This study evaluated HCV protease resistance profiles in the major six HCV genotypes and identified genetic barrier (GB) profiles to each available protease inhibitor across HCV strains from different locations worldwide. We obtained 15 099 HCV sequences from treatment-naïve subjects retrieved at the Los Alamos HCV Sequence Database. The wild-type codons of different HCV genotypes were used to analyse the smallest number of nucleotide substitution steps required for changing that codon to the closest one associated with drug resistance. The 36L and 175L RAVs were found as genetic signatures of genotypes 2-5, while the 80K RAV was found in all genotype 5 sequences. Genotypes 4 and 6 showed a higher GB to RAV mutations conferring resistance to telaprevir, while genotypes 2-5 presented baseline resistance to that drug, carrying the 36L mutation. Genotype 4 had a higher GB to simeprevir resistance, requiring three substitutions to acquire the 155K mutation. Subtype 1b showed a higher GB than subtype 1a to resistance for most PIs, with RAVs at codons 36 and 155. Geographic disparities were also found in frequencies of certain RAVs in genotypes 2 and 3. Under a scenario of unprecedented evolution of anti-HCV direct-acting agents, the genetic composition of the circulating HCV sequences should be evaluated worldwide to choose the most appropriate/feasible therapeutic schemes with the highest genetic barriers to resistance.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral , Hepacivirus/enzimologia , Polimorfismo Genético , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/genética , Substituição de Aminoácidos , Frequência do Gene , Genótipo , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/virologia , Humanos , Mutação de Sentido Incorreto
14.
Hum Reprod ; 31(10): 2292-302, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27591237

RESUMO

STUDY QUESTION: What is the risk of finding malignant cells in cryopreserved ovarian tissue from sarcoma patients? SUMMARY ANSWER: Minimal disseminated disease (MDD) was not detected in frozen-thawed ovarian tissue from 26 patients by any of the sensitive methods applied. WHAT IS KNOWN ALREADY: In case of leukemia, the risk of malignant cell transmission through the graft is well known and widely documented. However, for bone cancer, like Ewing sarcoma or osteosarcoma, only a small number of case reports, have been published. These cancers often affect prepubertal girls, in whom ovarian tissue cryopreservation and transplantation is the only option to preserve fertility. STUDY DESIGN, SIZE, DURATION: The presence of malignant cells in cryopreserved ovarian tissue from patients with bone/soft tissue sarcoma was investigated with disease-specific markers for each patient, using immunohistochemistry (IHC), FISH and real-time quantitative RT-PCR (qPCR), with the original tumor serving as a positive control. PARTICIPANTS/MATERIALS, SETTING, METHODS: Forty-eight sarcoma patients were enrolled in the study, 12 of whom subsequently died. In each case, tissue from the primary tumor was investigated in order to identify markers (immunohistochemical and/or molecular) to analyze the ovarian tissue case by case. Ovarian tissue from osteosarcoma (n = 15), liposarcoma (n = 1) and undifferentiated sarcoma (n = 5) patients could not be evaluated, as no specific markers were detected by FISH or sensitive IHC in any of their primary tumoral tissue. One patient with Li-Fraumeni syndrome was also excluded from the study. IHC analyses were therefore performed on ovarian tissue from 26 patients and qPCR on 19. The primary tumors involved were Ewing sarcoma family of tumors (n = 14), rhabdomyosarcoma (n = 7), synovial sarcoma (n = 2), clear cell sarcoma (n = 2) and a malignant peripheral nerve sheath tumor (n = 1). MAIN RESULTS AND THE ROLE OF CHANCE: MDD was not detected in any of the 26 analyzed samples using sensitive techniques in this largest reported series, even from patients who subsequently died and/or those who presented with metastasis (11/26), hence the most aggressive forms of bone cancer. Indeed, anti-CD99 IHC and PCR performed on patients presenting with Ewing sarcoma family of tumors (n = 14) was negative in all cases. In patients with soft tissue sarcoma (n = 12) primitive tumor markers were detected by IHC and were negative in ovarian tissue. PCR could only be performed in 6/12 of these patients, again proving negative. LIMITATIONS, REASONS FOR CAUTION: Cryopreserved ovarian fragments to be transplanted cannot be tested, so this analysis of malignant cells cannot guarantee that all cryopreserved fragments will not contain any disseminated disease. Moreover, molecular markers are not readily available for all types of tumors. WIDER IMPLICATIONS OF THE FINDINGS: These results are reassuring regarding the risk of malignant cells in the ovary for transplantation, as the study involves a large series including different types of sarcomas. We believe this will help clinicians in their patient counseling for fertility preservation and restoration. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the Fonds National de la Recherche Scientifique de Belgique-FNRS under Grants Nos 7.4578.14 (Télévie to MS) and 5/4/150/5 to MMD. The authors declare no competing financial interests.


Assuntos
Neoplasias Ósseas/patologia , Criopreservação , Preservação da Fertilidade/métodos , Ovário/patologia , Sarcoma/secundário , Adolescente , Adulto , Criança , Feminino , Humanos , Adulto Jovem
15.
Hum Reprod ; 31(2): 427-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26628641

RESUMO

STUDY QUESTION: Do primordial-primary versus secondary follicles embedded inside a fibrin matrix have different capabilities to survive and grow after isolation and transplantation? SUMMARY ANSWER: Mouse primordial-primary follicles showed a lower recovery rate than secondary follicles, but both were able to grow. WHAT IS KNOWN ALREADY: Fresh isolated mouse follicles and ovarian stromal cells embedded in a fibrin matrix are capable of surviving and developing after short-term autografting. STUDY DESIGN, SIZE, DURATION: In vivo experimental model using 11 donor Naval Medical Research Institute (NMRI) mice and 11 recipient severe combined immunodeficiency (SCID) mice. Both ovaries from all NMRI mice were mechanically disrupted and primordial-primary and secondary follicles were isolated with ovarian stromal cells. They were then encapsulated in a fibrin matrix composed of 12.5 mg/ml of fibrinogen (F12.5) and 1 IU/ml of thrombin (T1) (F12.5/T1), and grafted to the inner part of the peritoneum of SCID mice for 2 and 7 days. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study was conducted at the Gynecology Research Unit, Université Catholique de Louvain. All materials were used to conduct histological (H-E staining) and immunohistochemical (Ki67, TUNEL) analyses. MAIN RESULTS AND THE ROLE OF CHANCE: Although all grafted fibrin clots were recovered, the follicle recovery rate on day 2 was 16 and 40% for primordial-primary and secondary follicles respectively, while on day 7, it was 6 and 28%. The secondary group showed a significantly higher recovery rate than the primordial-primary group (23%, P-value <0.001). Follicles found in both groups were viable, as demonstrated by live/dead assays, and no difference was observed in the apoptosis rate between groups, as evidenced by TUNEL. Their growth to further stages was confirmed by Ki67 immunostaining. LIMITATIONS, REASONS FOR CAUTION: As demonstrated by our results, secondary follicles appear to be more likely to survive and develop than primordial-primary follicles in a fibrin matrix after both periods of grafting. These findings may also be attributed to the specific features of the fibrin matrix, which could benefit larger follicles, but not smaller follicles. WIDER IMPLICATIONS OF THE FINDINGS: This study is essential to understanding possible impairment caused by factors such as the isolation procedure or fibrin matrix composition to the survival and development of different follicle stages. It therefore provides the basis for further investigations with longer periods of grafting. STUDY FUNDING/COMPETING INTERESTS: This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (grant Télévie No. 7.4578.14 and 7.4627.13, grant 5/4/150/5 awarded to Marie-Madeleine Dolmans), Fonds Spéciaux de Recherche, Fondation St Luc, the Foundation Against Cancer, and the Region Wallone (Convention N°6519-OVART) and donations from Mr Pietro Ferrero, Baron Frère and Viscount Philippe de Spoelberch. None of the authors have any competing interests to declare.


Assuntos
Fibrina , Folículo Ovariano/transplante , Animais , Apoptose , Técnicas de Cultura de Células , Sobrevivência Celular , Transplante de Células/métodos , Feminino , Preservação da Fertilidade/métodos , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos SCID , Folículo Ovariano/citologia , Folículo Ovariano/crescimento & desenvolvimento , Células Estromais/citologia , Transplante Homólogo/métodos
16.
Tumour Biol ; 37(3): 4053-64, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26486327

RESUMO

Considering that scarce data are available on disease progression of feline mammary carcinoma (FMC), this study aimed to analyze the clinical, pathological, and immunophenotypic features collected from 61 queens with FMC and to compare the concordance ratios of the expression levels of five molecular markers (ER, PR, fHER2, CK5/6, and Ki-67) between primary tumors (PT) and metastatic lesions. The results showed that cats with luminal A mammary carcinomas (MC) had higher overall survival (924.6 days, p = 0.001) and longer disease-free period (385.4 days, p = 0.005) compared to the ones with other MC subtypes. In fact, queens with triple negative/basal-like MC showed the lowest survival (mean 156.2 days) and the shortest disease-free survival (mean 28 days) among the molecular subtypes of MC. The lung was the organ most frequently affected by metastases, and animals with lung and/or pleural metastases were more likely to display metastases at three or more locations (p = 0.039). A large heterogeneity in protein expression levels was found between PT and paired metastases, with both estrogen and progesterone receptors more likely to be downregulated in metastases. Paired metastases frequently had higher Ki-67 index than PT, whereas fHER2 overexpression was seen in 46 samples (30 %) and CK5/6 expression was found in 50.7 % of metastases (36/71). Results also revealed that disease progression leads to a high percentage of triple negative/basal-like metastases (9/23; 39.1 %) associated with the absence of luminal A subtype in distant metastases (0/23). This study highlights the prognostic importance of immunophenotyping of MC in cats, although the modified protein expression identified in metastases contributes to justify why possible targeted therapies may fail in some animals with metastatic disease. Altogether, the results obtained also demonstrate that FMC can be used as a model to study human breast cancer.


Assuntos
Carcinoma Papilar/veterinária , Neoplasias Mamárias Animais/metabolismo , Neoplasias de Mama Triplo Negativas/veterinária , Animais , Carcinoma Papilar/metabolismo , Carcinoma Papilar/mortalidade , Carcinoma Papilar/secundário , Doenças do Gato , Gatos , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Estimativa de Kaplan-Meier , Metástase Linfática , Neoplasias Mamárias Animais/mortalidade , Neoplasias Mamárias Animais/patologia , Análise Multivariada , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
17.
Diabetes Metab Res Rev ; 32(4): 429-35, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27094098

RESUMO

AIMS: This study aimed to derive a new model to classify subjects with diabetes and active diabetic foot ulcer by their risk of lower extremity amputation. METHODS: A prospective cohort study was conducted that included all subjects with diabetic foot ulcer attending our Hospital Diabetic Foot Clinic from 2010 to 2013. Variables were collected at baseline. Subjects were followed up until healing, lower extremity amputation, death or for at least 3 months. Logistic regression was used to derive the new model, and the area under the receiver operating characteristic curve was assessed to propose the model with the greatest discrimination. RESULTS: A total of 293 participants were included and followed for a median of 91 days. In 23.2% amputation was required, 5.1% died and 3.1% were lost. Our final model included the variables most commonly used in clinical practice for diabetic foot risk assessment (presence of neuropathy, foot deformity, peripheral arterial disease and previous foot complications) in addition to multiple diabetic foot ulcer, infection, gangrene and bone involvement. This model had an area under the receiver operating characteristic curve of 0.91 [95% confidence interval (CI) 0.87-0.95] and as classification of 0.89 (95% CI 0.84-0.93) for lower extremity amputation prediction. The high-risk group presented a positive likelihood ratio of 5 (95% CI 3-8) and predictive value of 58 (46-71). Only one minor lower extremity amputation occurred in the low-risk group. CONCLUSIONS: We propose a new classification: diabetic foot risk assessment (DIAFORA). This classification was equally or more accurate for lower extremity amputation prediction in diabetic foot ulcer patients when compared with the existing ones.


Assuntos
Amputação Cirúrgica/estatística & dados numéricos , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/etiologia , Extremidade Inferior/cirurgia , Modelos Estatísticos , Idoso , Feminino , Humanos , Masculino , Estudos Prospectivos , Curva ROC , Medição de Risco , Fatores de Risco , Cicatrização
18.
Diabetes Metab Res Rev ; 32 Suppl 1: 84-98, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26340966

RESUMO

BACKGROUND: Prevention of foot ulcers in patients with diabetes is extremely important to help reduce the enormous burden of foot ulceration on both patient and health resources. A comprehensive analysis of reported interventions is not currently available, but is needed to better inform caregivers about effective prevention. The aim of this systematic review is to investigate the effectiveness of interventions to prevent first and recurrent foot ulcers in persons with diabetes who are at risk for ulceration. METHODS: The available medical scientific literature in PubMed, EMBASE, CINAHL and the Cochrane database was searched for original research studies on preventative interventions. Both controlled and non-controlled studies were selected. Data from controlled studies were assessed for methodological quality by two independent reviewers. RESULTS: From the identified records, a total of 30 controlled studies (of which 19 RCTs) and another 44 non-controlled studies were assessed and described. Few controlled studies, of generally low to moderate quality, were identified on the prevention of a first foot ulcer. For the prevention of recurrent plantar foot ulcers, multiple RCTs with low risk of bias show the benefit for the use of daily foot skin temperature measurements and consequent preventative actions, as well as for therapeutic footwear that demonstrates to relieve plantar pressure and that is worn by the patient. To prevent recurrence, some evidence exists for integrated foot care when it includes a combination of professional foot treatment, therapeutic footwear and patient education; for just a single session of patient education, no evidence exists. Surgical interventions can be effective in selected patients, but the evidence base is small. CONCLUSION: The evidence base to support the use of specific self-management and footwear interventions for the prevention of recurrent plantar foot ulcers is quite strong, but is small for the use of other, sometimes widely applied, interventions and is practically nonexistent for the prevention of a first foot ulcer and non-plantar foot ulcer.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Pé Diabético/prevenção & controle , Medicina Baseada em Evidências , Medicina de Precisão , Terapia Combinada/tendências , Efeitos Psicossociais da Doença , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/epidemiologia , Pé Diabético/etiologia , Pé Diabético/terapia , Humanos , Cooperação do Paciente , Educação de Pacientes como Assunto , Recidiva , Fatores de Risco , Autocuidado/tendências , Sapatos/efeitos adversos
19.
Microb Ecol ; 72(2): 407-17, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27260154

RESUMO

We hypothesize that bacterial endophytes may enhance the competitiveness and invasiveness of Phragmites australis. To evaluate this hypothesis, endophytic bacteria were isolated from P. australis. The majority of the shoot meristem isolates represent species from phyla Firmicutes, Proteobacteria, and Actinobacteria. We chose one species from each phylum to characterize further and to conduct growth promotion experiments in Phragmites. Bacteria tested include Bacillus amyloliquefaciens A9a, Achromobacter spanius B1, and Microbacterium oxydans B2. Isolates were characterized for known growth promotional traits, including indole acetic acid (IAA) production, secretion of hydrolytic enzymes, phosphate solubilization, and antibiosis activity. Potentially defensive antimicrobial lipopeptides were assayed for through application of co-culturing experiments and mass spectrometer analysis. B. amyloliquefaciens A9a and M. oxydans B2 produced IAA. B. amyloliquefaciens A9a secreted antifungal lipopeptides. Capability to promote growth of P. australis under low nitrogen conditions was evaluated in greenhouse experiments. All three isolates were found to increase the growth of P. australis under low soil nitrogen conditions and showed increased absorption of isotopic nitrogen into plants. This suggests that the Phragmites microbes we evaluated most likely promote growth of Phragmites by enhanced scavenging of nitrogenous compounds from the rhizosphere and transfer to host roots. Collectively, our results support the hypothesis that endophytic bacteria play a role in enhancing growth of P. australis in natural populations. Gaining a better understanding of the precise contributions and mechanisms of endophytes in enabling P. australis to develop high densities rapidly could lead to new symbiosis-based strategies for management and control of the host.


Assuntos
Antibiose , Bactérias/metabolismo , Raízes de Plantas/microbiologia , Poaceae/microbiologia , Microbiologia do Solo , Bactérias/classificação , Bactérias/isolamento & purificação , Biomassa , Fungos/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Lipopeptídeos/biossíntese , Fixação de Nitrogênio , Fosfatos/metabolismo , Poaceae/crescimento & desenvolvimento , Simbiose
20.
Eur J Nutr ; 55(5): 1831-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26206564

RESUMO

PURPOSE: A comparison of resting metabolic rate (RMR), respiratory quotient (RQ) and body temperature between adults of African and European descent. METHOD: Twenty-nine sub-Saharan Africans (SSA; 13 men and 16 women) and thirty-two Australians of European descent (EUR; eight men and 24 women) had RMR and RQ measured by indirect calorimetry. Dual-energy X-ray absorptiometry was used to determine fat mass (FM), fat-free mass, bone mineral content (BMC), appendicular lean tissue mass and non-appendicular lean tissue mass. Total skeletal muscle mass (SMM) was predicted. Residual mass (RM) was the difference between body weight and the sum of FM, SMM and BMC. The short form of the International Physical Activity Questionnaire was used to determine habitual physical activity (PA). Tympanic in the ear temperature (IET) and forearm to fingertip temperature gradients (FFG) were monitored throughout the protocol. RESULTS: The unadjusted RMR of SSA was significantly lower compared to EUR. Adjusted for age, sex, season, PA, FM, BMC, SMM and RM, this difference in RMR was still evident (mean ± SE, SSA: 4880 ± 161 kJ/d vs. EUR: 5979 ± 111, P < 0.005). The same model of adjustment also uncovered a significantly lower adjusted IET (SSA: 35.26 °C ± 0.133 vs. EUR: 35.60 ± 0.091, P < 0.05), a higher adjusted RQ (SSA: 0.86 ± 0.014 vs. EUR: 0.83 ± 0.010, P < 0.05) but no difference in adjusted FFG. CONCLUSIONS: In this study, SSA had a lower RMR, higher RQ and lower IET relative to EUR Australians.


Assuntos
Metabolismo Basal , População Negra , Temperatura Corporal , Taxa Respiratória , População Branca , Absorciometria de Fóton , Tecido Adiposo/metabolismo , Austrália , Composição Corporal , Índice de Massa Corporal , Peso Corporal , Densidade Óssea , Calorimetria Indireta , Exercício Físico , Feminino , Humanos , Masculino , Músculo Esquelético/metabolismo , Inquéritos e Questionários
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