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1.
Anticancer Drugs ; 30(9): 959-963, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31517734

RESUMO

Malignant gastrointestinal neuroectodermal tumour is an extremely rare neoplasm that arises in the wall of the small bowel, stomach or large bowel in young-aged and middle-aged adults. Histologically, it is generally characterized by monomorphic cells with clear cytoplasma, S-100 protein expression, and EWSR1 gene translocation. To the best of our knowledge, we describe for the first time, the case of a young woman with a diagnosis of metastatic gastrointestinal neuroectodermal tumour arising from ileum, who had a childhood adrenal neuroblastoma with liver, bone and lymph nodes metastasis, treated with four cycles of chemotherapy with the schedule CADO-CVP (CADO: cyclophosphamide 300 mg/m/day on days 1-5, vincristine 1,5 mg/m/day on days 1 and 5, and doxorubicin 60 mg/m/day on day 5; CVP: cisplatin 40 mg/m/day on days 1-5 and etoposide 100 mg/m/day on days 1-5) followed by right adrenal, kidney, lymph nodes and liver lesion resection, conditioning chemotherapy (melphalan-carmustine-teniposide), stem cells autologous transplantation and consecutively radiotherapy on the spine (T9 to L3) for a total of 30 Gy. For the second diagnosis of gastrointestinal neuroectodermal tumour with liver metastasis, she underwent ileal tumour resection and platinum-anthracycline based chemotherapy with initial shrinkage of liver metastasis. Unfortunately, despite the initial response and the following delivered therapies, she died for rapid progressive disease. Taking into account the late effects of past therapeutic modalities, a long-term surveillance of young child treated for neuroblastoma, is required to appreciate their overall risks of second malignancies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Digestório/tratamento farmacológico , Neuroblastoma/tratamento farmacológico , Adulto , Feminino , Humanos
2.
Memory ; 23(4): 529-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24787135

RESUMO

In the present paper, we aimed to provide evidence in support of the idea tested in a recent study by Lanciano and colleagues that flashbulb memories (FBMs) are a special class of autobiographical memories that can be assessed through the autobiographical implicit association test (aIAT). FBMs and event memories (EMs) for the news of the resignation of Pope Benedict XVI were evaluated in three samples of churchgoer Catholic, non-churchgoer Catholic and Evangelical Italian participants through the traditional self-report measures (specificity/accuracy, confidence, consistency) and aIAT indices. Results confirmed the strength of the association between FBM and true information. The aIAT effect was stronger for FBMs than for EM details, and for Catholic respondents who were the group most concerned by the original event. Furthermore, the use of implicit measures for memory assessment concurs with the traditional self-report indices of FBMs. The present evidence supports the idea that FBMs are special autobiographical memories which remain detailed, certain and consistent over time.


Assuntos
Acontecimentos que Mudam a Vida , Memória Episódica , Religião e Psicologia , Emoções , Pessoas Famosas , Feminino , Humanos , Masculino , Testes Psicológicos , Adulto Jovem
3.
J Cell Physiol ; 227(12): 3744-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22495883

RESUMO

An excessive food supply has resulted in an increasing prevalence of overweight and obesity, conditions accompanied by serious health problems. Several studies have confirmed the significant inverse correlation between testosterone and obesity. Indeed after decades of intense controversy, a consensus has emerged that androgens are important regulators of fat mass and distribution in mammals and that androgen status affects cellularity in vivo. The high correlation of testosterone levels with body composition and its contribution to the balance of lipid metabolism are also suggested by the fact that testosterone lowering is associated with important clinical disorders such as dyslipidemia, atherosclerosis, cardiovascular diseases, metabolic syndrome and diabetes. In contrast, testosterone supplementation therapy in hypogonadic men has been shown to improve the lipid profile by lowering cholesterol, blood sugar and insulin resistance. Leptin, ghrelin and adiponectin are some of the substances related to feeding as well as androgen regulation. Thus, complex and delicate mechanisms appear to link androgens with various tissues (liver, adipose tissue, muscles, coronary arteries and heart) and the subtle alteration of some of these interactions might be the cause of correlated diseases. This review underlines some aspects regarding the high correlations between testosterone physiology and body fat composition.


Assuntos
Tecido Adiposo/metabolismo , Distribuição da Gordura Corporal , Testosterona/metabolismo , Biomarcadores , Dislipidemias/metabolismo , Humanos , Obesidade/metabolismo , Fatores de Risco
4.
World J Clin Oncol ; 12(5): 355-366, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34131567

RESUMO

BACKGROUND: Sarcopenia is a condition characterized by decreased skeletal muscle mass due to physiological ageing or to a concomitant disease such as neoplasia. In cancer patients, a low lean body mass is suggested to be a negative prognostic factor for survival and for the development of dose-limiting chemotherapy toxicities irrespective of disease stage. AIM: To evaluate the prognostic role of sarcopenia in patients with metastatic colorectal cancer (mCRC) undergoing first-line chemotherapy. METHODS: Our retrospective analysis included 56 mCRC patients who received first-line chemotherapy from 2014 to 2017 at the Medical Oncology Unit of our hospital. Computerized scans were performed before starting chemotherapy and at the first disease reassessment. Sarcopenia was assessed using the skeletal mass index = muscle area in cm2/(height in m2) calculated at the L3 vertebra. Overall survival and objective response rate were evaluated. Toxicities were analyzed during the first four cycles of therapy and graded according to Common Terminology Criteria for Adverse Events version 4.0. A loss of skeletal muscle mass ≥ 5% was considered indicative of deterioration in muscle condition. RESULTS: Median age was 67 years and 35.7% of patients were ≥ 70 years old. Fourteen patients (25%) were sarcopenic at baseline computed tomography (CT) scan (7/33 men; 7/23 women); 5/14 sarcopenic patients were ≥ 70 years old. Median follow-up was 26.8 mo (3.8-66.8 mo) and median overall survival was 27.2 mo (95%CI: 23.3-37.3). Sarcopenia was not correlated to overall survival (P = 0.362), to higher toxicities reported during the first 4 cycles of chemotherapy (P = 1.0) or to response to treatment (P = 0.221). At the first disease reassessment, a skeletal muscle loss (SML) ≥ 5% was found in 17 patients (30.3%) 3 of whom were already sarcopenic at baseline CT scan, while 7 patients became sarcopenic. SML was not correlated to overall survival (P = 0.961). No statistically significant correlation was found between baseline sarcopenia and age (P = 1.0), body mass index (P = 0.728), stage at diagnosis (P = 0.355) or neutrophil/lymphocyte ratio (P = 0.751). CONCLUSION: Neither baseline sarcopenia nor SML affected survival. In addition, baseline sarcopenia was not related to worse treatment toxicity. However, these results must be interpreted with caution due to the limited sample size.

5.
Antivir Ther ; 14(6): 869-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19812451

RESUMO

BACKGROUND: Telbivudine is a potent inhibitor of hepatitis B virus (HBV) replication without anti-HIV type-1 (HIV-1) activity demonstrated in vitro; however, very few clinical data on HIV-1-infected patients are available at present. Because it represents a therapeutic option in HIV-1-HBV-coinfected patients who do not require antiretroviral therapy, we strictly monitored three HIV-1-HBV-coinfected patients treated with telbivudine monotherapy for chronic hepatitis B. METHODS: We performed molecular analysis of HBV DNA and of HIV-1 reverse transcriptase and protease RNA and DNA sequences in three HIV-1-HBV-coinfected patients treated with telbivudine monotherapy. RESULTS: Despite a transient and deep reduction of HIV-1 RNA, observed in two of the three patients studied, no genotypic resistance mutations were detected on both HIV-1 and HBV viruses. CONCLUSIONS: Telbivudine therapy for 24 weeks showed a potent anti-HBV activity in HIV-1-positive, hepatitis B e antigen-positive patients with high HBV viraemia. No direct anti-HIV-1 activity of telbivudine was demonstrated and no genotypic resistance mutations to anti-HIV-1 drugs was found; however, the transient but deep reduction of HIV RNA, after telbivudine introduction, deserves further investigation and a strict monitoring of HIV-1 viraemia in HIV-1-infected patients on treatment with this drug.


Assuntos
Antivirais/uso terapêutico , Infecções por HIV/complicações , HIV-1 , Hepatite B Crônica/tratamento farmacológico , Nucleosídeos/uso terapêutico , Pirimidinonas/uso terapêutico , Adulto , Fármacos Anti-HIV , Humanos , Masculino , Telbivudina , Timidina/análogos & derivados
6.
AIDS Res Hum Retroviruses ; 23(9): 1146-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17919111

RESUMO

We investigated the prevalence and molecular epidemiology of human T cell lymphotropic virus type 1 in Peruvian HIV-1-positive subjects, and found a 10.1% prevalence in a consecutive series of 318 HIV-1-positive patients living in Lima. Phylogenetic analysis of the long terminal repeat of 10 patient isolates showed that all of them belonged to the HTLV-1aA (Transcontinental) subgroup. Although the majority of the Peruvian sequences included in the analysis formed a clade with other Latin American sequences, the isolates of three patients clustered significantly with South African strains. These data show a high prevalence of HTLV-1 infection in HIV-1-positive subjects living in Lima and confirm the presence in Latin America of HTLV-1 strains probably arising from South Africa.


Assuntos
Evolução Molecular , Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Filogenia , Adulto , Feminino , Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/classificação , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Masculino , Dados de Sequência Molecular , Peru/epidemiologia , Prevalência , Análise de Sequência de DNA , África do Sul
7.
Eurasian J Med ; 48(1): 10-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27026757

RESUMO

OBJECTIVE: Third-generation aromatase inhibitors (AI) are potent suppressors of aromatase activity. The aim of this study was to measure the incidence of adverse effects in breast cancer patients treated with AI-based adjuvant therapy and the relationship with the CYP19A1 genotypes. MATERIALS AND METHODS: Forty-five postmenopausal breast cancer patients (46-85 yrs) in AI adjuvant treatment were genotyped for the rs4646 polymorphisms of CYP19A1 gene and three variations were identified. Toxicities were registered at each follow-up medical examination, and classified in accord with the Common Terminology Criteria for Adverse Events. RESULTS: Twenty-four (53.3%) patients presented the GG genotype; 19 (42.2%) the GT, and 2 (4.4%) the TT. The AI treatment was Anastrazole for 35 patients (77.8%) and Letrozole for the others (n=10; 22.2%). Osteoporosis was significantly associated with the GG genotype (p=0.001). Treatment discontinuation (TD) was observed in 6 cases (13.3%). The only parameter able to predict TD was the appearance of severe arthralgia/myalgia (Odds Ratio, OR=23.75; p=0.009), when adjusted for age and AI treatment. CONCLUSION: Our results suggest that CYP19A1 polymorphic variants may influence susceptibility to develop AI-related side effects. Further prospective studies are needed to confirm the role of the aromatase gene (CYP19A1) polymorphisms in predicting adverse effects to AI-based therapy.

8.
PLoS One ; 11(2): e0148621, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26859495

RESUMO

The human ability of identifying, processing and regulating emotions from social stimuli is generally referred as Emotional Intelligence (EI). Within EI, Ability EI identifies a performance measure assessing individual skills at perceiving, using, understanding and managing emotions. Previous models suggest that a brain "somatic marker circuitry" (SMC) sustains emotional sub-processes included in EI. Three primary brain regions are included: the amygdala, the insula and the ventromedial prefrontal cortex (vmPFC). Here, our aim was to investigate the relationship between Ability EI scores and SMC activity during social judgment of emotional faces. Sixty-three healthy subjects completed a test measuring Ability EI and underwent fMRI during a social decision task (i.e. approach or avoid) about emotional faces with different facial expressions. Imaging data revealed that EI scores are associated with left insula activity during social judgment of emotional faces as a function of facial expression. Specifically, higher EI scores are associated with greater left insula activity during social judgment of fearful faces but also with lower activity of this region during social judgment of angry faces. These findings indicate that the association between Ability EI and the SMC activity during social behavior is region- and emotion-specific.


Assuntos
Inteligência Emocional/fisiologia , Emoções/fisiologia , Expressão Facial , Comportamento Social , Adulto , Tonsila do Cerebelo/anatomia & histologia , Tonsila do Cerebelo/fisiologia , Mapeamento Encefálico , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Feminino , Humanos , Julgamento/fisiologia , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/fisiologia , Adulto Jovem
9.
World J Oncol ; 6(4): 394-397, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28983337

RESUMO

BACKGROUND: The aim of the study was to assess the association of single nucleotide polymorphisms (SNPs) C677T and A1298C in the methylenetetrahydrofolate reductase gene with colorectal, esophageal/gastric and pancreatic cancer in a cohort of Italian patients. METHODS: A total of 790 cancer patients and 202 healthy controls were genotyped and distributions in genotype and allele frequencies were compared by Chi-squared analysis and logistic regression analysis. RESULTS: According to most of previous findings, we found an effect of the C677T variant, but no effect of the A1298C, in colorectal and esophageal/gastric, whereas no association was evidenced with pancreatic cancer. We found that only homozygous TT carriers of the C677T variant had an increased risk for onset of cancer. CONCLUSION: This result could be related to dietary and behavioral habits of the analyzed population, which could mitigate the deleterious effect of the T allele in heterozygosity and it highlights the importance to validate genetic determinant of cancer risk in different population and geographical areas.

10.
World J Oncol ; 6(5): 437-440, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28983344

RESUMO

BACKGROUND: The aim of the study was to validate the association between the Arg166His polymorphisms of the Fc immunoglobulin receptor 2A (FCGR2A) and the Val212Phe of FCGR3A and pathological clinical response (pCR) to trastuzumab in HER2-positive breast cancer patients. METHODS: Polymorphisms were characterized by pyrosequencing in 26 patients with ductal histotype breast cancer in a neoadjuvant setting and genotype association with pCR was analyzed. RESULTS: No association was found between the FCGR3A Val212Phe polymorphisms and pCR. In contrast, the FCGR2A GG genotype (Arg allele) was found to be positively associated with pCR (P = 0.012). CONCLUSIONS: Our results do not support previously reported data on the effect of polymorphisms in immunoglobulin Fc receptors upon response to trastuzumab therapy.

11.
Pain Physician ; 15(3 Suppl): ES111-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22786450

RESUMO

BACKGROUND: Gonadal hormones are critical factors in modulating the experience of pain, as suggested by the several sex differences observed: women have a greater risk of many clinical pain conditions, and postoperative and procedural pain may be more severe in them than in men. A growing body of literature demonstrates the role of estrogen in the female pain experience, whereas less attention has been given to testosterone and its functions. Nevertheless, testosterone has an appreciable role in both women and men: adequate serum levels are required in males and females for libido and sexuality; cellular growth; maintenance of muscle mass and bone; healing; blood-brain barrier; and for central nervous system maintenance. Pain therapy, and particularly opioid therapy, has been shown to affect testosterone plasma levels. Thus, the chronic administration of pain killers, such as opioids, requires the physician to be aware of both the consequences that can develop due to long-term testosterone impairment and the available means to restore and maintain physiological testosterone levels. OBJECTIVE: The objective is to highlight to pain physicians that the endocrine changes occurring during chronic pain therapy can participate in the body dysfunctions often present in chronic pain patients and that there are possible hormone replacement methods that can be carried out in men and women to improve their quality of life. STUDY DESIGN: A comprehensive review of the literature. METHODS: A comprehensive review of the literature relating to opioid-induced hypogonadism, as well as other very common forms of hypogonadism, its endocrine effects, and possible therapeutic actions. The literature was collected from electronic and other sources. The reviewed literature included observational studies, case reports, systematic reviews, and guidelines. OUTCOME MEASURES: Evaluation of the endocrine changes described in chronic pain therapy was the primary outcome measure. The secondary outcome measures were functional improvement and adverse effects of hormone replacement. RESULTS: The results of the survey clearly show that sex hormone determination is very rare in pain centers. Given the complexity and widespread nature of pain therapy, there is a paucity of qualitative and quantitative literature regarding its endocrine consequences. The available evidence is weak for pain relief, but is consistent for many collateral effects, possibly deriving from pain therapy, such as fatigue, depression, and neurodegenerative diseases. LIMITATION: This is a narrative review without application of methodological quality assessment criteria. Even so, there is a paucity of literature concerning both controlled and observational literature for the endocrine effects of most analgesic drugs. CONCLUSION: Testosterone replacement suffers from old prejudices about its utility and safety. With this review we illustrate the available therapeutic choices able to maintain T concentration into physiological ranges and reduce nociception with a final goal of improving patients' quality of life.


Assuntos
Analgésicos Opioides/efeitos adversos , Dor Crônica/tratamento farmacológico , Terapia de Reposição Hormonal/métodos , Hipogonadismo/induzido quimicamente , Feminino , Humanos , Hipogonadismo/tratamento farmacológico , Masculino , Caracteres Sexuais , Testosterona/uso terapêutico
12.
PLoS One ; 6(1): e16551, 2011 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21304985

RESUMO

HIV/HCV coinfected individuals under highly active antiretroviral therapy (HAART) represent an interesting model for the investigation of the role played by the immune system in driving the evolution of the HCV quasispecies. We prospectively studied the intra-host evolution of the HCV heterogeneity in 8 coinfected subjects, selected from a cohort of 32 patients initiating HAART: 5 immunological responders (group A) and 3 immunological non-responders (group B), and in two HCV singly infected controls not assuming drugs (group C). For all these subjects at least two serial samples obtained at the first observation (before HAART) and more than 1 year later, underwent clonal sequence analysis of partial E1/E2 sequences, encompassing the whole HVR1. Evolutionary rates, dated phylogenies and population dynamics were co-estimated by using a Bayesian Markov Chain Monte Carlo approach, and site specific selection pressures were estimated by maximum likelihood-based methods. The intra-host evolutionary rates of HCV quasispecies was 10 times higher in subjects treated with HAART than in controls without immunodeficiency (1.9 and 2.3 × 10(-3) sub/site/month in group A and B and 0.29 × 10(-3) sub/site/month in group C individuals). The within-host Bayesian Skyline plot analysis showed an exponential growth of the quasispecies populations in immunological responders, coinciding with a peak in CD4 cell counts. On the contrary, quasispecies population remained constant in group B and in group C controls. A significant positive selection pressure was detected in a half of the patients under HAART and in none of the group C controls. Several sites under significant positive selection were described, mainly included in the HVR1. Our data indicate that different forces, in addition to the selection pressure, drive an exceptionally fast evolution of HCV during HAART immune restoration. We hypothesize that an important role is played by the enlargement of the viral replicative space.


Assuntos
Terapia Antirretroviral de Alta Atividade/efeitos adversos , Evolução Biológica , Infecções por HIV/tratamento farmacológico , HIV-1 , Hepacivirus/genética , Hepatite C/genética , Seleção Genética/efeitos dos fármacos , Teorema de Bayes , Comorbidade , Infecções por HIV/complicações , Infecções por HIV/imunologia , Hepacivirus/efeitos dos fármacos , Hepatite C/complicações , Humanos , Sistema Imunitário , Filogenia , Estudos Prospectivos
13.
Infect Genet Evol ; 10(2): 215-20, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19932194

RESUMO

Human bocavirus (HBoV) is a linear single-stranded DNA virus belonging to the Parvoviridae family that has recently been isolated from the upper respiratory tract of children with acute respiratory infection. All of the strains observed so far segregate into two genotypes (1 and 2) with a low level of polymorphism. Given the recent description of the infection and the lack of epidemiological and molecular data, we estimated the virus's rates of molecular evolution and population dynamics. A dataset of forty-nine dated VP2 sequences, including also eight new isolates obtained from pharyngeal swabs of Italian patients with acute respiratory tract infections, was submitted to phylogenetic analysis. The model parameters, evolutionary rates and population dynamics were co-estimated using a Bayesian Markov Chain Monte Carlo approach, and site-specific positive and negative selection was also investigated. Recombination was investigated by seven different methods and one suspected recombinant strain was excluded from further analysis. The estimated mean evolutionary rate of HBoV was 8.6x10(-4)subs/site/year, and that of the 1st+2nd codon positions was more than 15 times less than that of the 3rd codon position. Viral population dynamics analysis revealed that the two known genotypes diverged recently (mean tMRCA: 24 years), and that the epidemic due to HBoV genotype 2 grew exponentially at a rate of 1.01year(-1). Selection analysis of the partial VP2 showed that 8.5% of sites were under significant negative pressure and the absence of positive selection. Our results show that, like other parvoviruses, HBoV is characterised by a rapid evolution. The low level of polymorphism is probably due to a relatively recent divergence between the circulating genotypes and strong purifying selection acting on viral antigens.


Assuntos
Teorema de Bayes , Bocavirus/genética , Infecções por Parvoviridae/virologia , Evolução Molecular , Feminino , Humanos , Lactente , Masculino , Cadeias de Markov , Método de Monte Carlo , Faringe/virologia , Filogenia , Recombinação Genética , Infecções Respiratórias/virologia , Seleção Genética
14.
Virology ; 380(1): 84-90, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18715605

RESUMO

The epidemiological history of HBV genotypes A and D and subgenotypes A2 and D3 was studied on 132 isolates drawn between 1980 and 2005 from patients living in a homogenous geographical area. Evolutionary rates and divergence dates were estimated and HBV demographic history was reconstructed by using a statistical approach based on coalescent theory. The evolutionary rate of A2 was significantly lower than that of D3. The growth rate of D3 epidemic was significantly faster than that of A2; both subgenotypes showed a decreasing growth rate from the mid-1980s. Our data suggest that the important discrepancies observed in the evolutionary rates of HBV genotypes A and D may reflect different population dynamics of their epidemics. These results show the usefulness of phylodynamic studies in reconstructing the history of epidemics due to highly variable DNA viruses, and in evaluating the long-term efficacy of prophylactic measures.


Assuntos
Evolução Molecular , Genoma Viral , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Proteínas Virais/genética , Variação Genética , Genótipo , Vírus da Hepatite B/imunologia , Humanos , Filogenia , Recombinação Genética , Proteínas Virais/química
15.
J Acquir Immune Defic Syndr ; 47(3): 269-73, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18398969

RESUMO

The aim of this study was to assess the prevalence and the molecular epidemiology of human T-lymphotropic virus type 1 (HTLV-1) in a group of pregnant women living in Guinea Bissau. We studied 427 consecutive pregnant women attending 10 centers for HIV-1 infection monitoring in Bissau. HTLV-1 infection was found in 2.6% of the patients. Phylogenetic analysis of the long terminal repeat region showed that 10 isolates were of the cosmopolitan subtype (HTLV-1a) and that only 1 was of the widespread Central African subtype (HTLV-1b). All the cosmopolitan isolates belonged to the HTLV-1aD subgroup, which was first described in North Africa and clustered with other Senegal and Guinea isolates to form a significant West African clade. Our data show a high prevalence of HTLV-1 in Guinea Bissau and suggest the existence of a trans-Saharan strain distributed in North and West Africa, which probably crossed the desert in the past as a result of contacts between nomadic and sedentary populations or along trading routes.


Assuntos
Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Adolescente , Adulto , DNA Viral/química , DNA Viral/genética , Feminino , Guiné-Bissau/epidemiologia , Infecções por HTLV-I/sangue , Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/classificação , Humanos , Dados de Sequência Molecular , Filogenia , Gravidez , Prevalência , Análise de Sequência de DNA , Sequências Repetidas Terminais/genética
16.
Virology ; 365(1): 113-24, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17451771

RESUMO

The genetic heterogeneity of hepatitis B virus (HBV) genotypes and subgenotypes was investigated by directly sequencing amplified PreS, S and P genes of HBV isolates obtained from the plasma of 99 subjects with chronic HBV infection. Genotype D showed the greatest intragenotypic and intrasubgenotypic divergence: in particular, the a determinant was mutated in 58.2% of the genotype D patients, two of whom showed prototypic vaccine-induced escape mutants at codon 145. Moreover, five sites under significant positive selection were found in the S protein of the D isolates: one in the a determinant and four in the highly hydrophobic C terminal. Our results suggest that careful surveillance of vaccine-induced escape mutants should be considered in populations with highly frequent genotype D infections, and raise questions concerning the possible relationship between the genetic heterogeneity, host immunity and pathogenicity of this HBV genotype.


Assuntos
Heterogeneidade Genética , Antígenos de Superfície da Hepatite B/análise , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B do Pato/genética , Sequência de Aminoácidos , DNA Viral/análise , Feminino , Genótipo , Antígenos de Superfície da Hepatite B/química , Vírus da Hepatite B do Pato/classificação , Humanos , Masculino , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
17.
J Virol ; 79(14): 9145-56, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15994809

RESUMO

The aim of this study was to investigate the quasispecies heterogeneity of hepatitis C virus (HCV) in the plasma, cryoprecipitate, and peripheral lymphocytes of chronically infected HCV patients with mixed cryoglobulinemia (MC). We studied 360 clones from 10 HCV-positive patients with MC and 8 age-, gender- and HCV genotype-matched subjects with chronic HCV infection but without MC. A partial nucleotide sequence encompassing the E1/E2 region, including hypervariable region 1 (HVR1), was amplified and cloned from plasma, cryoprecipitates, and peripheral blood mononuclear cells (PBMC), and the genetic diversity and complexity and synonymous and nonsynonymous substitution rates were determined. Heterogeneous selection pressure at codon sites was evaluated. Compartmentalization was estimated by phylogenetic and phenetic (Mantel's test) approaches. The patients with MC had 3.3 times lower nonsynonymous substitution rates (1.7 versus 5.7 substitutions/100 sites). Among the subjects with HCV genotype 1, the MC patients had significantly less complexity than the controls, whereas the diversity and complexity were similar in the genotype 2 patients and controls. Site-specific selection analysis confirmed the low frequency of MC patients showing positive selection. There was a significant correlation between positive selection and the infecting HCV genotype. The quasispecies were less heterogeneous in PBMC than in plasma. Significant compartmentalization of HCV quasispecies was observed in the PBMC of four of nine subjects (three with MC) and seven of nine cryoprecipitates. In one subject with MC, we detected a 5-amino-acid insertion at codons 385 to 389 of HVR1. Our results suggest reduced quasispecies heterogeneity in MC patients that is related to a low selection pressure which is probably due to an impaired immune response, the HCV genotype, and/or the duration of the infection. The frequent HCV quasispecies compartmentalization in patients' PBMC suggests a possible pathogenetic significance.


Assuntos
Crioglobulinemia/virologia , Hepacivirus/classificação , Leucócitos Mononucleares/virologia , Idoso , Sequência de Aminoácidos , Crioglobulinemia/sangue , Feminino , Hepacivirus/fisiologia , Humanos , Funções Verossimilhança , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Viral/sangue , Proteínas do Envelope Viral/química
18.
J Med Virol ; 74(2): 207-15, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15332268

RESUMO

Human T-lymphotropic virus type 1 and 2 (HTLV-1 and HTLV-2) infections in Europe are limited to intravenous drug users and migrants coming from areas in which they are endemic. A survey was undertaken of HTLV-1 and HTLV-2 infections in 393 recent immigrants: 167 HIV-1 positive subjects (including 52 male-to-female transsexual sex workers) and 226 pregnant HIV-1 negative women. The prevalence of HTLV-1 was 3.6% in the HIV-1 positive group and 0.9% in the HIV-1 negative group. The highest HTLV-1 prevalence in both groups was found in persons from Latin America, particularly those born in Peru (up to 26% in the HIV-1 positive group). All of the HIV-1/HTLV-1 co-infected individuals were male-to-female transsexual sex workers in whom the overall prevalence of HTLV-1 infection was 11.5%. HTLV-2 was only found in the HIV-1 positive group (prevalence 1.2%); all of the infected subjects were transsexual sex workers from Brazil (overall prevalence 6.4%). Phylogenetic analysis showed that all of the HTLV-1 isolates were of the cosmopolitan type, clustering with other strains circulating in the patients' birthplaces; the HTLV-2 isolates were of subtype 2a, and clustered significantly with other Brazilian strains. These results suggest the independent origin of each infection in the patient's birthplace. The data raise concerns about the further spread of HTLV infections mainly through the sexual route.


Assuntos
Emigração e Imigração , Infecções por HIV/complicações , Infecções por HTLV-I/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Trabalho Sexual , Transexualidade , Adulto , Feminino , Infecções por HIV/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano/classificação , Vírus Linfotrópico T Tipo 1 Humano/genética , Humanos , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA
19.
J Acquir Immune Defic Syndr ; 31(4): 440-7, 2002 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12447016

RESUMO

One thousand one hundred fifty-two HIV-1-positive patients were screened for HTLV-2 infection, and the AIDS-free coinfected individuals were consecutively included in a longitudinal study with the aim of investigating the role of HTLV-2 in the progression to AIDS and the development of specific neurologic diseases. Two matched HIV-1-positive/HTLV-2-negative controls for each coinfected individual were also enrolled in the study. HTLV-2 infection was found in 95 (8.2%) of the HIV-1-positive patients, 30 of whom were followed up for a median of 28.5 months. No significant differences were observed between them and the patients infected with HIV-1 alone in terms of the rate of decline in CD4 cell counts, progression to AIDS, or AIDS mortality, but they had an increased risk of developing peripheral neuropathy (hazard ratio, 3.3; 95% confidence interval, 1.3-8.0; p =.009). One coinfected patient developed myelopathy during the follow-up. In the second part of the study, aimed at preliminarily assessing the effect of highly active antiretroviral therapy (HAART) on the incidence of peripheral neuropathy, we extended our observations to two groups of coinfected and singly infected individuals receiving HAART. An 80% decrease in incidence of peripheral neuropathy was observed among both groups without any significant difference between them. These results support the hypothesis that HTLV-2 plays a role in the development of neurologic abnormalities in HIV-1-infected patients and suggest that the immune reconstitution due to HAART may limit the activity of HTLV-2 as an opportunistic agent.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Infecções por HTLV-II/complicações , Doenças do Sistema Nervoso Periférico/epidemiologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Intervalos de Confiança , Progressão da Doença , Feminino , HIV-1 , Humanos , Masculino , Probabilidade , Análise de Regressão , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo
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