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1.
Sci Total Environ ; 915: 170157, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38242447

RESUMO

Changes in habitat characteristics are known to have profound effects on biotic communities and their functional traits. In the context of an urban-rural gradient, urbanisation drastically alters abiotic characteristics, e.g., by increasing environmental temperatures and through light pollution. These abiotic changes significantly impact the functional traits of organisms, particularly insects. Furthermore, changes in habitat characteristics also drive changes in the behavioural traits of animals, allowing them to adapt and thrive in new environments. In our study, we focused on the synanthropic ant species Lasius niger as a model organism. We conducted nocturnal field observations and complemented them with laboratory experiments to investigate the influence of night warming (NW) associated with Urban Heat Islands (UHI), light pollution (ALAN), and habitat type on ant foraging behaviour. In addition, we investigated the influence of elevated temperatures on brood development and worker mortality. Our findings revealed that urban populations of L. niger were generally more active during the night compared to their rural counterparts, although the magnitude of this difference varied with specific city characteristics. In laboratory settings, higher temperatures and continuous illumination were associated with increased activity level in ants, again differing between urban and rural populations. Rural ants exhibited more locomotion compared to their urban counterparts when maintained under identical conditions, which might enable them to forage more effectively in a potentially more challenging environment. High temperatures decreased the developmental time of brood from both habitat types and increased worker mortality, although rural colonies were more strongly affected. Overall, our study provides novel insights into the influence of urban environmental stressors on the foraging activity pattern and colony development of ants. Such stressors can be important for the establishment and spread of synanthropic ant species, including invasive ones, and the biotic homogenization of anthropogenic ecosystems.


Assuntos
Formigas , Ecossistema , Animais , Cidades , Níger , Temperatura Alta
2.
Radiography (Lond) ; 30(3): 986-994, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38678978

RESUMO

INTRODUCTION: To investigate the predictive value of the pre-treatment diffusion parameters of diffusion-weighted magnetic resonance imaging (DW-MRI) using artificial intelligence (AI) for prostate-specific antigen (PSA) response in patients with low- and intermediate-risk prostate cancer (PCa) treated with stereotactic ablative radiotherapy (SABR). METHODS: Retrospective evaluation was performed for 30 patients using pre-treatment multi-parametric MR image datasets between 2017 and 2021. MR-based mean- and minimum apparent diffusion coefficients (ADCmean, ADCmin) were calculated for the intraprostatic dominant lesion. Therapeutic response was assessed using PSA levels. Predictive performance was assessed by the receiver operating characteristic (ROC) analysis. Statistics performed with a significance level of p ≤ 0.05. RESULTS: No biochemical relapse was detected after a median follow-up of twenty-three months (range: 3-50), with a median PSA of 0.01 ng/ml (range: 0.006-2.8) at the last examination. Significant differences were observed between the pre-treatment ADCmean, ADCmin parameters, and the group averages of patients with low and high 1-year-PSA measurements (p < 0.0001, p < 0.0001). In prediction, the random forest (RF) model outperformed the decision tree (DT) and support vector machine (SVM) models by yielding area under the curves (AUC), with 0.722, 0.685, and 0.5, respectively. CONCLUSION: Our findings suggest that pre-treatment MR diffusion data may predict therapeutic response using the novel approach of machine learning in PCa patients treated with SABR. IMPLICATIONS FOR PRACTICE: Clinicians shall measure and implement the evaluation of the suggested parameters (ADCmin, ADCmean) to provide the most accurate therapy for the patient.


Assuntos
Inteligência Artificial , Imagem de Difusão por Ressonância Magnética , Valor Preditivo dos Testes , Antígeno Prostático Específico , Neoplasias da Próstata , Radiocirurgia , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Projetos Piloto , Idoso , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética/métodos , Radiocirurgia/métodos , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Idoso de 80 Anos ou mais
3.
Mater Sci Eng C Mater Biol Appl ; 131: 112481, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34857267

RESUMO

A sterically stabilized unilamellar nanocarrier vesicle (SSV) system containing dipalmitoylphosphatidylcholine, cholesterol, ursolic acid and PEGylated phospholipid has been developed by exploiting the structural advantages of ursolic acid: by spontaneously attaching to the lipid head groups, it induces curvature at the outer side of the bilayers, allowing the preparation of size-limited vesicles without extrusion. Ursolic acid (UA) also interacts with the PEG chains, supporting steric stabilization even when the amount of PEGylated phospholipid is reduced. Using fluorescence immunohistochemistry, vesicles containing ursolic acid (UA-SSVs) were found to accumulate in the tumor in 3 h on xenografted mouse, suggesting the potential use of these vesicles for passive tumor targeting. Further on, mono- and combination therapy with UA and six different kinase inhibitors (crizotinib, erlotinib, foretinib, gefitinib, refametinib, trametinib) was tested on seven cancer cell-lines. In most combinations synergism was observed, in the case of trametinib even at very low concentration (0.001 µM), which targets the MAPK pathway most often activated in human cancers. The coupled intercalation of UA and trametinib (2:1 molar ratio) into vesicles causes further structural advantageous molecular interactions, promoting the formation of small vesicles. The high drug:lipid molar ratio (~0.5) in the novel type of co-delivery vesicles enables their direct medical application, possibly also overcoming the multidrug resistance effect.


Assuntos
Antineoplásicos , Neoplasias , Triterpenos , Animais , Antineoplásicos/farmacologia , Portadores de Fármacos , Camundongos , Triterpenos/farmacologia , Ácido Ursólico
4.
J Virol Methods ; 154(1-2): 76-81, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18835300

RESUMO

A novel DNA detection assay comprising Hybrid Capture sample preparation, GP5+/6+ PCR with modifications and Luminex 100 detection was developed and applied to genotyping of human papillomavirus (HPV) in cervical samples. Target-specific sample preparation was performed using magnetic beads conjugated with Hybrid Capture (HC) antibody. DNA-RNA hybrids were formed between DNA target and RNA probes and captured on HC-beads. DNA on magnetic beads was amplified without elution using consensus GP5+/6+ PCR and then genotyped on Luminex beads using hybridization probes for the 17 high-risk HPV types 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 73, 82 and an internal control. This new sequence-specific Hybrid Capture sample preparation is fast, efficient and allows direct HPV genotyping by PCR. Compared to traditional non-sequence-specific sample preparation methods, HC sample preparation demonstrated slightly better detection of multiple HPV infections. The clinical utility of this method was demonstrated on cervical samples positive for HR HPV by the Hybrid Capture 2 (hc2) screening assay.


Assuntos
Hibridização de Ácido Nucleico/métodos , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Reação em Cadeia da Polimerase/métodos , Colo do Útero/virologia , Feminino , Genótipo , Humanos , Sondas de Oligonucleotídeos/genética , Papillomaviridae/genética , Sondas RNA/genética
5.
J Med Screen ; 15(2): 97-104, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18573778

RESUMO

OBJECTIVES: To assess whether human papillomavirus (HPV) testing is a safe enough approach to warrant extension of the screening intervals of baseline Papanicolaou (Pap)-/HPV- women in low-income settings. METHODS: Of the >1000 women prospectively followed up as part of the Latin American Screening (LAMS) Study in São Paulo, Campinas, Porto Alegre) and Buenos Aires, 470 women with both baseline cytology and Hybrid Capture 2 (HC2) results available were included in this analysis. These baseline Pap-negative and HC2- or HC2+ women were controlled at six-month intervals with colposcopy, HC2 and Pap to assess the cumulative risk of incident Pap smear abnormalities and their predictive factors. RESULTS: Of the 470 women, 324 (68.9%) were high-risk HPV (hrHPV) positive and 146 (31.1%) were negative. Having two or more lifetime sex partners (odds ratio [OR] = 2.63; 95% CI 1.70-3.51) and women using hormonal contraception (OR = 2.21; 95% CI 1.40-3.51) were at increased risk for baseline hrHPV infection. Baseline hrHPV+ women had a significantly increased risk of incident abnormal Pap smears during the follow-up. Survival curves deviate from each other starting at month 24 onwards, when hrHPV+ women start rapidly accumulating incident Pap smear abnormalities, including atypical squamous cells (ASC) or worse (log-rank; P < 0.001), low-grade squamous intraepithelial lesions (LSIL) or worse (P < 0.001) and high-grade squamous intraepithelial lesions (HSIL) (P = 0.03). Among the baseline hrHPV- women, the acquisition of incident hrHPV during the follow-up period significantly increased the risk of incident cytological abnormalities (hazard ratio = 3.5; 95% CI 1.1-11.7). CONCLUSION: These data implicate that HPV testing for hrHPV types might be a safe enough approach to warrant extension of the screening interval of hrHPV-/Pap-women even in low-resource settings. Although some women will inevitably contract hrHPV, the process to develop HSIL will be long enough to enable their detection at the next screening round (e.g. after three years).


Assuntos
Programas de Rastreamento/métodos , Papillomaviridae , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adolescente , Adulto , Estudos de Coortes , Colposcopia , Feminino , Humanos , América Latina , Pessoa de Meia-Idade , Teste de Papanicolaou , Infecções por Papillomavirus/virologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal/métodos , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia
6.
Int J STD AIDS ; 19(4): 251-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18482945

RESUMO

Drug abuse (addiction) has been listed among the risk factors for human papillomavirus (HPV) infections, but no case-control studies exist to rule out sexual behaviour and other potential confounders. The aim of this study is to evaluate the role of drug addiction as an independent predictor of HR-HPV infections and (cervical intraepithelial neoplasia) CIN2+ in an age-matched case-control (1:4) study nested within the prospective Latin American Screening (LAMS) study cohort. All 109 women in the LAMS cohort (n=12,114) reporting drug abuse/addiction were matched with four controls (n = 436) of non-abusers strictly by age. Conditional logistic regression analysis was used to estimate the co-variates of drug abuse, and the whole series (n=545) was analysed for predictors of HR-HPV and CIN2+ using univariate and multivariate regression models. Oncogenic HPV infections were significantly (P=0.019) more prevalent among abusers (37.7%) than in controls (21.9%), but there was no difference in high-grade squamous intraepithelial lesions (P=0.180) or CIN2+ lesions (P=0.201). In multivariate conditional logistic regression, number of lifetime sexual partners (P=0.0001), ever smokers (P=0.0001), non-use of OCs (P=0.013), ever having sexually transmitted diseases (STD) (P=0.041) and no previous Pap smear (P=0.027) were independent co-variates of drug addiction. Drug abuse was not an independent risk factor of high-risk (HR)-HPV infection, which was significantly predicted by (1) age below 30 years (P=0.045), (2) more than five lifetime sexual partners (P=0.046) and (3) being current smoker (P=0.0001). In multivariate model, only HR-HPV infection was an independent risk factor of CIN2+ (P=0.031), with adjusted OR=11.33 (95% CI 1.25-102.50). These data indicate that drug addiction is not an independent risk factor of either HR-HPV infections or CIN2+, but the increased prevalence of HR-HPV infections is explained by the high-risk sexual behaviour and smoking habits of these women.


Assuntos
Infecções por Papillomavirus/complicações , Transtornos Relacionados ao Uso de Substâncias/complicações , Displasia do Colo do Útero/complicações , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou , Fatores de Risco , Esfregaço Vaginal
7.
Nat Neurosci ; 3(4): 366-71, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10725926

RESUMO

Networks of GABAergic interneurons are implicated in synchronizing cortical activity at gamma frequencies (30-70 Hz). Here we demonstrate that the combined electrical and GABAergic synaptic coupling of basket cells instantaneously entrained gamma-frequency postsynaptic firing in layers 2/3 of rat somatosensory cortex. This entrainment was mediated by rapid curtailment of gap junctional coupling potentials by GABAA receptor-mediated IPSPs. Electron microscopy revealed spatial proximity of gap junctions and GABAergic synapses on somata and dendrites. Electrical coupling alone entrained postsynaptic firing with a phase lag, whereas unitary GABAergic connections were ineffective in gamma-frequency phasing. These observations demonstrate precise spatiotemporal mechanisms underlying action potential timing in oscillating interneuronal networks.


Assuntos
Comunicação Celular/fisiologia , Junções Comunicantes/fisiologia , Interneurônios/fisiologia , Sinapses/fisiologia , Ácido gama-Aminobutírico/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Fatores Etários , Animais , Bicuculina/farmacologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Antagonistas GABAérgicos/farmacologia , Junções Comunicantes/ultraestrutura , Interneurônios/citologia , Microscopia Eletrônica , Ratos , Ratos Wistar , Sinapses/ultraestrutura
8.
Clin Drug Investig ; 28(10): 657-68, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18783304

RESUMO

BACKGROUND AND OBJECTIVES: Surgical extraction of an impacted third molar is generally followed by acute post-operative pain that has been shown to be primarily inflammatory. Thus, use of NSAIDs in this context is appropriate and has been shown to be effective. Several drugs are employed for this purpose, but no information exists on the reasons why preference is given to one rather than another. The principal objective of this study was to evaluate the pattern of administration of NSAIDs in patients undergoing surgery for impacted third molar extraction. The study also aimed to collect information on the efficacy, onset and duration of the analgesic effect of routinely prescribed NSAIDs and to assess the duration of treatment with these drugs and their tolerability. METHODS: This was an observational, multicentre, prospective survey. A total of 616 patients (38% male and 62% female) from the Italian Stomatology Clinics of the Universities of Bologna, Brescia, Cagliari, Chieti, Pavia, Pisa, Siena and Varese and from the Department of Oral and Maxillo-Facial Surgery of Semmelweis University, Budapest, were eligible for the study. Patients were evaluated over the 7 days following surgical extraction. NSAIDs were prescribed according to the normal prescribing habits of the centre and physician involved. The main outcomes of interest in the survey were the efficacy, onset and duration of analgesic effect, duration of therapy, and tolerability of the NSAIDs prescribed. RESULTS: Nimesulide was the most prescribed NSAID (68%), followed by diclofenac, ketoprofen and ibuprofen. Because of the low proportion of patients receiving other NSAIDs, these patients were considered a single treatment group for evaluation purposes. Nimesulide, especially when given before patients started experiencing pain after surgery, was more effective than other NSAIDs in reducing the severity of pain on the day of surgery, in delaying the time to maximum intensity of pain, in providing complete pain relief and in prolonging the duration of analgesic effect on the day of surgery. These results are consistent with the known anti-inflammatory and analgesic actions of nimesulide and with the important role of inflammation in the onset of pain after this type of surgery. CONCLUSION: These results confirm nimesulide as an effective reference drug for the treatment of post-operative dental pain and show that it has a positive benefit/risk profile in this setting.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Prescrições de Medicamentos/estatística & dados numéricos , Dente Serotino/cirurgia , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Inquéritos de Saúde Bucal , Diclofenaco/administração & dosagem , Diclofenaco/uso terapêutico , Feminino , Humanos , Hungria , Ibuprofeno/administração & dosagem , Ibuprofeno/uso terapêutico , Itália , Cetoprofeno/administração & dosagem , Cetoprofeno/uso terapêutico , Masculino , Medição da Dor/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Resultado do Tratamento
9.
Mol Cell Biol ; 6(11): 4099-103, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3540606

RESUMO

Eleven independently isolated temperature-sensitive mutations in the cell division cycle gene CDC28 were mapped with respect to the DNA sequence of the wild-type gene and then sequenced to determine the precise nature of each mutation. The set yielded six different point mutations, each of which predicts a single amino acid substitution in the CDC28 product. The positions of the mutations did not correlate in any obvious way with observable biological characteristics of the mutant alleles. When the positions of substitutions were collated with a predicted secondary structural analysis of the CDC28 protein kinase, they were found to correlate strongly with probable regions of structural transition.


Assuntos
Proteínas Fúngicas/genética , Genes Fúngicos , Mutação , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Divisão Celular , DNA Fúngico/genética , Saccharomyces cerevisiae/citologia , Temperatura
10.
Mol Cell Biol ; 2(12): 1532-49, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14582195

RESUMO

We examined the synthesis and turnover of individual proteins in the Saccharomyces cerevisiae cell cycle. Proteins were pulse-labeled with radioactive isotope (35S or 14C) in cells at discrete cycle stages and then resolved on two-dimensional gels and analyzed by a semiautomatic procedure for quantitating gel electropherogram-autoradiographs. The cells were obtained by one of three methods: (i) isolation of synchronous subpopulations of growing cells by zonal centrifugation.; (ii) fractionation of pulse-labeled steady-state cultures according to cell age; and (iii) synchronization of cells with the mating pheromone, alpha-factor. In confirmation of previous studies, we found that the histones H4, H2A, and H2B were synthesized almost exclusively in the late G1 and early S phases. In addition, we identified eight proteins whose rates of synthesis were modulated in the cell cycle, and nine proteins (of which five, which may well be related, were unstable, with half-lives of 10 to 15 min) that might be regulated in the cell cycle by periodic synthesis, modification, or degradation. Based on the time of maximal labeling in the cell cycle and on experiments with alpha-factor and hydroxyurea, we assigned the cell cycle proteins to two classes: proteins in class I were labeled principally in early G1 phase and at a late stage of the cycle, whereas those in class II were primarily synthesized at times ranging from late G1 to mid S phase. At least one major control point for the cell cycle proteins occurred between "start" and early S phase. A set of stress-responsive proteins was also identified and analyzed. The rates of synthesis of these proteins were affected by certain perturbations that resulted during selection of synchronous cell populations and by heat shock.


Assuntos
Ciclo Celular/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Autorradiografia , Radioisótopos de Carbono/metabolismo , Replicação do DNA , Eletroforese em Gel Bidimensional , Histonas/química , Histonas/metabolismo , Hidroxiureia , Inibidores da Síntese de Ácido Nucleico/metabolismo , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/química , Radioisótopos de Enxofre/metabolismo
11.
Endocr Relat Cancer ; 13(2): 279-92, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16728564

RESUMO

Breast cancer continues to be a major health problem for women in the USA and worldwide. There is a need to identify and take steps to alter modifiable breast cancer risks. Conditions of obesity and overweight are risk factors that have reached epidemic proportions. This article reviews the evidence in the literature that test mechanism-based hypotheses which attempt to provide a molecular basis for a causal link between obesity and breast cancer risk, particularly the effects of metabolic syndrome and insulin resistance, peripheral estrogen aromatization in adipose tissue, and direct effect of adipokines. Future areas for study and implications for therapy are discussed.


Assuntos
Neoplasias da Mama/etiologia , Estrogênios/metabolismo , Insulina/metabolismo , Obesidade/complicações , Adipócitos/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Feminino , Humanos , Resistência à Insulina , Obesidade/metabolismo , Obesidade/terapia
12.
J Natl Cancer Inst ; 92(10): 818-25, 2000 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-10814677

RESUMO

BACKGROUND: In many low-resource settings, there are barriers to cytologic screening for cervical cancer. This study evaluates human papillomavirus (HPV) DNA testing as an alternative screening method. METHODS: Cervical samples from 2944 previously unscreened South African women aged 35-65 years were tested for high-risk types of HPV with the use of the Hybrid Capture I (HCI) assay. Women also had a Pap smear, direct visual inspection of the cervix, and Cervicography(TM). Women positive on any screening test were referred for colposcopy. Samples from women with biopsy-confirmed, low-grade squamous intraepithelial lesions (SILs) (n = 95), high-grade SILs (n = 74), or invasive cervical cancer (n = 12) and a random sample of women with no cervical disease (n = 243) were retested for HPV DNA with the use of the more sensitive Hybrid Capture II (HCII) assay. All P values are two-sided. RESULTS: High-risk HPV DNA was detected in 73.3% and 88.4% of 86 women with high-grade SIL or invasive cancer and in 12.2% of 2680 and 18.1% of 243 women without evidence of cervical disease, with the use of the HCI and HCII assays, respectively. HPV DNA testing with the HCII assay was more sensitive than cytology for detecting high-grade SIL and invasive cancer (McNemar's test, P =.04), and testing with the HCI assay was of equivalent sensitivity (P =.61). Cytology had a statistically significantly better specificity (96.8%) than either the HCI assay (87.8%) or the HCII assay (81.9%) (P<.01). Receiver operating characteristic curves identified test cutoff values that allow HPV DNA testing to identify 57% of women with high-grade SIL or cancer, while classifying less than 5% of women with no cervical disease as HPV DNA positive. CONCLUSIONS: HPV DNA testing has a sensitivity equivalent to, or better than, that of cytology. Since HPV DNA testing programs may be easier to implement than cytologic screening, HPV testing should be considered for primary cervical cancer screening in low-resource settings.


Assuntos
DNA Viral/análise , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/diagnóstico , Adulto , Idoso , Estudos de Avaliação como Assunto , Feminino , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Teste de Papanicolaou , Papillomaviridae/genética , Valor Preditivo dos Testes , Sensibilidade e Especificidade , África do Sul , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/diagnóstico
13.
J Natl Cancer Inst ; 79(4): 671-7, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2821311

RESUMO

Molecular hybridization analysis of human papillomavirus (HPV) DNA from 190 cervical biopsy specimens from women in the United States, Brazil, and Peru revealed viral sequences in 2 (9%) of 23 biopsy specimens of normal mature squamous epithelium, 7 (44%) of 16 biopsy specimens of metaplastic squamous epithelia, 60 (77%) of 78 cervical intraepithelial neoplasia (CIN), 57 (89%) of 64 invasive squamous carcinomas, and 8 (89%) of 9 endocervical adenocarcinomas. HPV typing by DNA hybridization revealed HPV 6 and HPV 11 sequences in metaplastic squamous epithelia, CIN I, and CIN II, but not in CIN III lesions or invasive carcinomas. HPV 16 was detected in metaplastic epithelium and in nearly half of the invasive squamous carcinomas and adenocarcinomas. It was present in 31% of CIN lesions, increasing in frequency with the severity of CIN from 20% of CIN I to 50% of CIN III. HPV 16 showed a striking difference in geographic distribution, being detected in 36% of the carcinomas from the United States compared to 64% of the carcinomas from Brazil and Peru. HPV 18 was found in metaplastic epithelia and in 17% of carcinomas but in only 1% of CIN lesions. HPV 31 was not found in metaplastic epithelium but was present in 6% of carcinomas and in 18% of CIN lesions. In addition, a group of uncharacterized HPVs, not corresponding to any of the probes used, was found in 5% of normal and metaplastic epithelia and in 18% of CIN and 19% of invasive cancers. These results suggest that individual HPV types that infect the cervix have varying degrees of oncogenic association. HPV 6 and HPV 11 appear to have very little oncogenic association, HPV 31 has low oncogenic association, and HPV 16 and HPV 18 have high oncogenic association.


Assuntos
Oncogenes , Infecções Tumorais por Vírus/genética , Neoplasias do Colo do Útero/microbiologia , Biópsia , Brasil , DNA Viral/análise , Feminino , Humanos , Papillomaviridae/genética , Peru , Infecções Tumorais por Vírus/epidemiologia , Estados Unidos , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/genética
14.
Cancer Res ; 56(17): 3967-74, 1996 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8752165

RESUMO

Human papillomavirus (HPV) is believed to be the major cause of cervical cancer. To investigate whether a cellular immune response, especially a T helper type 1 response, is related to the natural defense against HPV-related cervical lesions, the interleukin 2 response of peripheral blood lymphocytes in vitro to overlapping peptides from HPV-16 E6 and E7 oncoproteins was compared with the degree of cervical cytological abnormality among 140 women in a cross-sectional study. We compared 66 women diagnosed with low-grade squamous intraepithelial lesions (LSIL), 21 with high-grade squamous intraepithelial lesions (HSIL), and 28 with invasive cervical cancer with 25 women who were cytologically normal but previously HPV-16 DNA positive. The fraction showing strong interleukin 2 production against HPV-16 peptides was greatest among cytologically normal women (35%) and declined with increasing disease severity [LSIL] (20%), HSIL, (17%), and cancer patients (7%); X2 test P for the trend = 0.02], whereas the responses against a recall influenza antigen were not significantly different among groups. Our finding suggests that a T helper lymphocyte type 1 response to HPV antigens is associated with disease status. This result may reflect a targeted effect of the disease on immune function or a protective effect of the immune response against disease progression.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Interleucina-2/biossíntese , Proteínas Oncogênicas Virais/farmacologia , Proteínas Repressoras , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Carcinoma de Células Escamosas/imunologia , Estudos Transversais , DNA Viral/análise , Feminino , Humanos , Interleucina-2/sangue , Ativação Linfocitária , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estadiamento de Neoplasias , Papillomaviridae/imunologia , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/imunologia , Infecções Tumorais por Vírus/sangue , Infecções Tumorais por Vírus/imunologia , Neoplasias do Colo do Útero/imunologia , Displasia do Colo do Útero/imunologia
15.
J Neurosci ; 21(15): 5824-31, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11466454

RESUMO

Distinct interneuron populations innervate perisomatic and dendritic regions of cortical cells. Perisomatically terminating GABAergic inputs are effective in timing postsynaptic action potentials, and basket cells synchronize each other via gap junctions combined with neighboring GABAergic synapses. The function of dendritic GABAergic synapses in cortical rhythmicity, and their interaction with electrical synapses is not understood. Using multiple whole-cell recordings in layers 2-3 of rat somatosensory cortex combined with light and electron microscopic determination of sites of interaction, we studied the interactions between regular spiking nonpyramidal cells (RSNPCs). Random samples of unlabeled postsynaptic targets showed that RSNPCs placed GABAergic synapses onto dendritic spines (53 +/- 12%) and shafts (45 +/- 10%) and occasionally somata (2 +/- 4%). GABAergic interactions between RSNPCs were mediated by 4 +/- 2 axodendritic synapses and phased postsynaptic activity at beta frequency but were ineffective in phasing at gamma rhythm. Electrical interactions of RSNPCs were transmitted via two to eight gap junctions between dendritic shafts and/or spines. Elicited at beta and gamma frequencies, gap junctional potentials timed postsynaptic spikes with a phase lag, however strong electrical coupling could synchronize presynaptic and postsynaptic activity. Combined unitary GABAergic and gap junctional connections of moderate strength produced beta and gamma frequency synchronization of the coupled RSNPCs. Our results provide evidence that dendritic GABAergic and/or gap junctional mechanisms effectively transmit suprathreshold information in a population of interneurons at behaviorally relevant frequencies. A coherent network of GABAergic cells targeting the dendrites could provide a pathway for rhythmic activity spatially segregated from perisomatic mechanisms of synchronization.


Assuntos
Córtex Cerebral/metabolismo , Dendritos/metabolismo , Junções Comunicantes/metabolismo , Interneurônios/metabolismo , Sinapses/metabolismo , Ácido gama-Aminobutírico/metabolismo , Potenciais de Ação/fisiologia , Animais , Análise por Conglomerados , Eletroencefalografia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Técnicas In Vitro , Rede Nervosa/fisiologia , Periodicidade , Células Piramidais/metabolismo , Ratos , Ratos Wistar , Córtex Somatossensorial/fisiologia
16.
J Clin Oncol ; 6(7): 1177-83, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3392562

RESUMO

Twenty-one patients with tumor stage mycosis fungoides (MF) with or without lymph node (LN) involvement, were treated with total skin electron beam irradiation (TSEB) followed by six monthly cycles of systemic chemotherapy (CT) of either mechlorethamine (HN2) or cyclophosphamide (CTX) with vincristine (VCR), procarbazine, and prednisone (PRD) (COPP or MOPP). All patients had complete clearing of the skin after TSEB. However, while receiving chemotherapy, two patients developed visceral involvement and eight patients relapsed with limited cutaneous plaques (LCP). The median duration of remission was 12 months from the completion of TSEB, and all patients relapsed with cutaneous plaques within 25 months. Complete remission was again achieved using additional electron irradiation and maintenance therapy in all but one patient. Multiple cutaneous recurrences occurred in all patients. Median survival from the initiation of TSEB is 6 years. Five patients are living beyond 8 years (four off treatment without disease for 1 to 7 years). LN involvement did not influence initial response or survival. Combined modality therapy for tumor stage MF using TSEB followed by systemic CT and subsequent maintenance therapy may lead eventually to prolonged disease-free survival (DFS) in selected patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Micose Fungoide/tratamento farmacológico , Micose Fungoide/radioterapia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Terapia Combinada , Ciclofosfamida/administração & dosagem , Feminino , Seguimentos , Humanos , Masculino , Mecloretamina/administração & dosagem , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Prognóstico , Indução de Remissão , Vincristina/administração & dosagem
17.
Anticancer Res ; 25(5): 3469-80, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16101165

RESUMO

OBJECTIVES: This is a European Commission (EC)-funded ongoing study known as the LAMS (Latin American Screening) study, where PAP smear/liquid-based cytology and screening colposcopy were compared with i) three optional screening tools [visual inspection with acetic acid (VIA), or Lugol's iodine (VILI), cervicography] and with ii) Hybrid Capture II from a) conventional samples and from b) self-samples, in women at different risk for cervical cancer in Brazil and Argentina. STUDY DESIGN: During 2002-2003, a cohort of 12,107 women attending four clinics: Campinas (CA), Sao Paulo (SP), Porto Alegre (PA) and Buenos Aires (BA), were interviewed for risk factors, and examined using the 8 diagnostic arms. Colposcopy was performed for women positive in any test and for 5% of women with baseline PAP-negative and 20% of HCII-negatives. All high-grade lesions (CIN2/3) were treated, and low-grade CIN are prospectively followed-up. RESULTS: Of the 12,107 women, the following baseline data are available: epidemiological data (n=11,996), conventional PAP smears (n=10,363), LBC, SurePATH (n=320), LBC, DNA-Citoliq (n=1,346), VIA (n=12.067), VILI (n=3,061), cervicography (n=279), screening colposcopy (n=3,437), HCII conventional (n=4,710), HCII self-sampling (n=246) and cervical biopsies (n=1,524). The four sub-cohorts differ significantly in all their baseline data on the implicated risk factors of cervical cancer, consonant with their origin from regions with different cancer incidence. Around 95% of all PAP smears were negative, with slight variations in the prevalence of LSIL and HSIL between the four centers. Significant differences were found in the detection rates of abnormal findings in VIA, VILI and colposcopy between the four centers (p=0.0001). The prevalence of HPV was practically identical (16.5-18.8%) in all four cohorts (p=0.486), with no differences in the relative viral loads. Biopsy results were different depending on whether the women underwent screening colposcopy (BA) or elective colposcopy (others). CONCLUSION: Four cohorts with significantly different baseline data are available, and prospective follow-up of these women permits analysis of whether variations in cervical cancer incidence in these regions is due to i) different natural history of the precursor lesions, or ii) due to different levels of exposure to the known risk factors.


Assuntos
Programas de Rastreamento/métodos , Neoplasias do Colo do Útero/diagnóstico , Adulto , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Colo do Útero/citologia , Colo do Útero/virologia , Colposcopia , Feminino , Humanos , Teste de Papanicolaou , Papillomaviridae , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/patologia , Fatores de Risco , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
18.
J Med Screen ; 12(3): 142-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16156945

RESUMO

OBJECTIVES: To assess the performance indicators of visual inspection with acetic acid (VIA) and visual inspection with Lugol's iodine (VILI) in four Latin American centres participating in the ongoing Latin AMerican Screening (LAMS) study, in settings with moderate incidence of cervical disease and with poorly to moderately well-organized cervical cancer screening. SETTING: Three Brazilian centres (São Paulo, Campinas and Porto Alegre) and one Argentine centre (Buenos Aires) recruited a total of 11,834 healthy women to undergo VIA, VILI, conventional Pap smear and Hybrid Capture II (HCII). METHODS: Women who had a positive result from any of these tests were subjected to colposcopy and biopsies (if necessary), and women with high-grade cervical intraepithelial neoplasia (CIN) were properly treated. To control for verification bias, 5% of women with normal tests were referred for colposcopy, as were 20% of HCII-negative women. RESULTS: Data on VIA (n=11,834), VILI (n=2994), conventional Pap smear (n=10,138) and HCII (n=4195) were available for test comparisons, calculating sensitivity, specificity, and positive and negative predictive values. Overall test positivity was 11.6% for VIA, 23.0% for VILI, 2.2% for Pap smear (LSIL threshold), 1.1% for Pap smear (HSIL threshold) and 17.1% for HCII. VIA was positive in 61.8% of the women with CIN 1, 57.0% of those with CIN 2, 35.0% of women with CIN 3 and in 21 of 28 (75%) of women with cancer. Approximately 10% of women with no detectable disease had an abnormal VIA. Regarding VILI, 83.3% of women diagnosed with CIN 1 and 62.5% of those with CIN 3 had an abnormal test. VILI failed to detect one of three cases of cancer. Both the sensitivity, specificity and positive predictive value of VIA and VILI in detecting CIN 2 or CIN 3 could be significantly improved depending on the combination with Pap smear or HCII (sensitivity up to 100.0% and specificity up to 99.8%). CONCLUSIONS: The LAMS study failed to reproduce the performance figures obtained with VIA and VILI (as stand-alone tests) in some other settings, where the prevalence of cervical disease was higher. However, a combined use of VIA or VILI with the Pap test or HCII allowed specific detection of cervical abnormalities.


Assuntos
Ácido Acético/farmacologia , Colo do Útero/virologia , Iodetos/farmacologia , Programas de Rastreamento/métodos , Teste de Papanicolaou , Papillomaviridae/metabolismo , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal/métodos , Adulto , Colo do Útero/patologia , Corantes/farmacologia , Feminino , Humanos , América Latina , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/virologia
19.
J Invest Dermatol ; 90(3): 331-5, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2450141

RESUMO

To gain preliminary data on the location of a 195 kD cell peripheral protein of epidermal keratinocytes recognized by monoclonal antibody AE11, immunofluorescence staining was carried out on cultured human epidermal cells. B11 antidesmosomal polyclonal antibody and AE3 antikeratin monoclonal antibody staining were used as comparative reference controls. Desmosomal antigens span the cell membrane and keratins constitute a family of cytoplasmic proteins. The cultured cells were systematically used either unfixed, fixed with 4% paraformaldehyde, or fixed with methanol at 4 degrees C. The former two preparations were designed to expose only the surface antigens, whereas the latter method permeated the membrane to allow cytoplasmic staining. Differences in staining patterns were observed in the basal layer as compared with the upper layers with all three antibodies. B11 antidesmosomal antibody staining was consistent in pattern after either paraformaldehyde or methanol fixation. In addition to the punctate staining along adjacent cell surfaces as shown in the basal layer, the surface planes of the upper cells exhibited parallel arrays of linear streaks, demonstrating the distribution of desmosomal proteins. Antikeratin staining by AE3 showed the typical filamentous staining in basal cells. However, a homogeneous patchy staining of suprabasal cells was observed. The presence of punctate surface staining using antikeratin antibody on paraformaldehyde fixed cells suggests leakage of keratin to the cell surface. AE11 showed stronger staining in the top cells on methanol treated cultures and a punctate surface staining of the cells fixed with paraformaldehyde. These observations provide useful preliminary information in localizing peripheral proteins in epidermal keratinocytes.


Assuntos
Epiderme/análise , Queratinas/análise , Proteínas/análise , Células Cultivadas , Imunofluorescência , Formaldeído/farmacologia , Técnicas Histológicas , Humanos , Metanol/farmacologia , Pênfigo/metabolismo , Polímeros/farmacologia
20.
J Invest Dermatol ; 69(5): 439-41, 1977 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-333032

RESUMO

Specific antitreponemal antibodies have been demonstrated by immunofluorescence techniques in the lymphoplasmocytic infiltrates which characterize early symphilitic lesions. A purified suspension of Nichols strain Treponema pallidum was sonified and labeled with fluorescein isothiocyanate and applied to cryostat sections of 12 biopsy specimens from the cutaneous lesions of 11 patients with proven secondary syphilis, using a modified direct immunofluorescence procedure. Specimens from various inflammatory dermatoses processed similarly served as controls. Granular fluorescence was noted in the dermis in 9 of the 12 specimens corresponding to areas of heavy plasma cell infiltration and some fluorescence was found directly on plasma cells which were identified by subsequent hematoxylin and eosin staining. This fluorescence could be blocked by prior incubation of the sections with unlabeled sonified treponemal suspension. Control slides did not reveal any fluorescence. The use of labeled treponemal antigen may aid the tissue diagnosis of early syphilitic lesions which can mimic a variety of dermatological disorders.


Assuntos
Anticorpos Antibacterianos/análise , Sífilis Cutânea/imunologia , Biópsia , Imunofluorescência , Humanos , Tiocianatos , Treponema pallidum
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