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1.
Cell ; 168(1-2): 311-324.e18, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-28086095

RESUMO

Superior predatory skills led to the evolutionary triumph of jawed vertebrates. However, the mechanisms by which the vertebrate brain controls predation remain largely unknown. Here, we reveal a critical role for the central nucleus of the amygdala in predatory hunting. Both optogenetic and chemogenetic stimulation of central amygdala of mice elicited predatory-like attacks upon both insect and artificial prey. Coordinated control of cervical and mandibular musculatures, which is necessary for accurately positioning lethal bites on prey, was mediated by a central amygdala projection to the reticular formation in the brainstem. In contrast, prey pursuit was mediated by projections to the midbrain periaqueductal gray matter. Targeted lesions to these two pathways separately disrupted biting attacks upon prey versus the initiation of prey pursuit. Our findings delineate a neural network that integrates distinct behavioral modules and suggest that central amygdala neurons instruct predatory hunting across jawed vertebrates.


Assuntos
Núcleo Central da Amígdala/fisiologia , Comportamento Predatório , Animais , Ansiedade/metabolismo , Núcleo Central da Amígdala/anatomia & histologia , Eletromiografia , Interneurônios/metabolismo , Mandíbula/anatomia & histologia , Mandíbula/inervação , Mandíbula/fisiologia , Camundongos , Pescoço/anatomia & histologia , Pescoço/inervação , Pescoço/fisiologia , Neurônios/citologia , Neurônios/fisiologia , Substância Cinzenta Periaquedutal/fisiologia
2.
J Neurosci ; 41(25): 5399-5420, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-33883203

RESUMO

The brainstem dorsal periaqueductal gray (dPAG) has been widely recognized as being a vital node orchestrating the responses to innate threats. Intriguingly, recent evidence also shows that the dPAG mediates defensive responses to fear conditioned contexts. However, it is unknown whether the dPAG displays independent or shared patterns of activation during exposure to innate and conditioned threats. It is also unclear how dPAG ensembles encode and predict diverse defensive behaviors. To address this question, we used miniaturized microscopes to obtain recordings of the same dPAG ensembles during exposure to a live predator and a fear conditioned context in male mice. dPAG ensembles encoded not only distance to threat, but also relevant features, such as predator speed and angular offset between mouse and threat. Furthermore, dPAG cells accurately encoded numerous defensive behaviors, including freezing, stretch-attend postures, and escape. Encoding of behaviors and of distance to threat occurred independently in dPAG cells. dPAG cells also displayed a shared representation to encode these behaviors and distance to threat across innate and conditioned threats. Last, we also show that escape could be predicted by dPAG activity several seconds in advance. Thus, dPAG activity dynamically tracks key kinematic and behavioral variables during exposure to threats, and exhibits similar patterns of activation during defensive behaviors elicited by innate or conditioned threats. These data indicate that a common pathway may be recruited by the dPAG during exposure to a wide variety of threat modalities.SIGNIFICANCE STATEMENT The dorsal periaqueductal gray (dPAG) is critical to generate defensive behaviors during encounters with threats of multiple modalities. Here we use longitudinal calcium transient recordings of dPAG ensembles in freely moving mice to show that this region uses shared patterns of activity to represent distance to an innate threat (a live predator) and a conditioned threat (a shock grid). We also show that dPAG neural activity can predict diverse defensive behaviors. These data indicate the dPAG uses conserved population-level activity patterns to encode and coordinate defensive behaviors during exposure to both innate and conditioned threats.


Assuntos
Comportamento Animal/fisiologia , Medo/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
3.
Eur J Neurosci ; 56(6): 4788-4802, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35971965

RESUMO

We examined the behavioural responses and Fos expression pattern of rats that were exposed to snake threats from shed snakeskin and a live snake. We differentiated the behavioural responses and the pattern of Fos expression in response to the odour cues and mild threat from a live snake. Animals exposed to the snake odour alone or to the confined snake showed a great deal of risk assessment. Conversely, the intensification of odour during exposure to the live snake decreased the threat ambiguity, and the animals froze for a significantly longer period. Our Fos analysis showed that a pathway formed by the posteroventral part of the medial amygdalar nucleus to the central part of the ventromedial hypothalamic nucleus appeared to be solely responsive to odour cues. In addition, we showed increased Fos expression in a parallel circuit comprising the lateral amygdalar nucleus, ventral subiculum, lateral septum, and juxtadorsomedial region of the lateral hypothalamic area that is responsive to both the odour and mild threat from a live snake. This path is likely to process the environmental boundaries of the threat to be avoided. Both paths merge into the dorsal premammillary nucleus and periaqueductal grey sites, which all increase Fos expression in response to the snake threats and are likely to organize the defensive responses. Moreover, we found that the snake threat mobilized the Edinger-Westphal and supraoculomotor nuclei, which are involved in stress adaptation and attentional mechanisms.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Comportamento Animal , Animais , Complexo Nuclear Basolateral da Amígdala/metabolismo , Comportamento Animal/fisiologia , Medo/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Serpentes/metabolismo
4.
Eur J Neurosci ; 55(6): 1504-1518, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35229373

RESUMO

The dorsal periaqueductal grey (PAG) is an important site for integrating predatory threats. However, it remains unclear whether predator-related activation in PAG primarily reflects threat itself and thus can distinguish between various degrees of threat, or rather reflects threat-oriented behaviours, with the PAG potentially orchestrating different types of defensive repertoire. To address this issue, we performed extracellular recording of dorsal PAG neurons in freely behaving rats and examined neuronal and behavioural responses to stimulus conditions with distinct levels of predatory threat. Animals were sequentially exposed to a nonthreatening stimulus familiar environment (exposure to habituated environment) and to a novel nonthreatening stimulus (i.e., a toy animal-plush) and to conditions with high (exposure to a live cat), intermediate (exposure to the environment just visited by the cat, with remnant predator scent), and low (exposure on the following day to the predatory context) levels of predatory threat. To test for contributions of both threat stimuli and behaviour to changes in firing rate, we applied a Poisson generalized linear model regression, using the different predator stimulus conditions and defensive repertoires as predictor variables. Analysis revealed that the different predator stimulus conditions were more predictive of changes in firing rate (primarily threat-induced increases) than the different defensive repertoires. Thus, the dorsal PAG may code for different levels of predatory threat, more than it directly orchestrates distinct threat-oriented behaviours. The present results open interesting perspectives to investigate the role of the dorsal PAG in mediating primal emotional and cognitive responses to fear-inducing stimuli.


Assuntos
Medo , Substância Cinzenta Periaquedutal , Animais , Medo/fisiologia , Neurônios/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Comportamento Predatório/fisiologia , Ratos , Ratos Wistar
5.
Sex Transm Dis ; 46(10): 663-669, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31464859

RESUMO

BACKGROUND: Global variation in human papillomavirus (HPV) prevalence and persistence may be explained by differences in risk factors, such as sexual activity, oral contraceptive use, and behavioral factors. We evaluated determinants of acquisition and clearance of HPV infection among young women previously unexposed to HPV. METHODS: Five hundred thirty-four women aged 15 to 25 years who were cytology and HPV DNA negative, and seronegative for anti-HPV-16/18 antibodies, were recruited (July 2000-September 2001) from study centers in Brazil, the United States, and Canada (NCT00689741/NCT00120848). They were followed up for 76 months. Cervical samples were HPV genotyped via polymerase chain reaction. We used multivariable (forward stepwise, P = 0.15) Cox proportional hazards regression to estimate rate ratios (RR) and 95% confidence intervals (CI), separately according to length of follow-up time. RESULTS: On short-term follow-up (0-27 months), 257 (48%; 8535.80 person-months; incidence rate = 30.11; 95% CI, 26.64-34.02) incident HPV infections were detected. Marital status, lifetime number of sex partners, history of any sexually transmitted disease, and occasional use of oral contraceptives were strongly associated with acquisition of any HPV. Having 2 or more lifetime sex partners (RR, 2.03; 95% CI, 1.37-3.02) and a history of any sexually transmitted disease (RR, 1.98; 95% CI, 1.19-3.29) were the most important determinants of high-risk HPV (hrHPV) incidence. During the entire follow-up (0-76 months), an increased hrHPV clearance was found among women in North America (RR, 1.38; 95% CI, 1.08-1.78) and black women (RR, 1.64; 95% CI, 1.04-2.60). Greater number of lifetime partners was associated with reduced clearance rates for any HPV (RR, 0.65; 95% CI, 0.43-0.98). CONCLUSIONS: We identified variation in risk of HPV acquisition and clearance among women unexposed to HPV at baseline.


Assuntos
Colo do Útero/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Adolescente , Adulto , Brasil , Canadá , Estudos de Coortes , Método Duplo-Cego , Feminino , Genótipo , Humanos , Incidência , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , Prevalência , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Estados Unidos , Adulto Jovem
6.
J Med Virol ; 90(5): 998-1001, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29288577

RESUMO

Human T-cell lymphotropic virus types 1/2 (HTLV-1/2) are transmitted through sexual intercourse, transfusion of blood components, and vertical transmission, predominantly through breastfeeding. Six hundred forty-three pregnant women from a high-risk prenatal care unit at a general hospital were tested by serological tests using chemiluminescence (CMIA) for screening, followed by a molecular confirmatory test. Four patients (0.6%) tested positive for HTLV-1/2 by CMIA, two samples (0.3%) for each patient were confirmed as having HTLV-1 or HTLV-2 by PCR. The results show the importance of inclusion of HTLV-1/2 screening for pregnant women in high-risk prenatal care and the need for a molecular biological method to confirm HTLV-1/2 infection.


Assuntos
Infecções por HTLV-I/diagnóstico , Infecções por HTLV-II/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Complicações Infecciosas na Gravidez/diagnóstico , Adolescente , Adulto , Estudos Transversais , Feminino , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Gravidez , Prevalência , Testes Sorológicos/métodos , Adulto Jovem
7.
Gynecol Oncol ; 151(2): 319-326, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30172480

RESUMO

OBJECTIVE: The present study aimed to evaluate the association between altered methylation and histologically confirmed high grade cervical intraepithelial neoplasia (hgCIN). METHODS: Methylation levels in selected host (CADM1, MAL, DAPK1) and HPV (L1_I, L1_II, L2) genes were measured by pyrosequencing in DNA samples obtained from 543 women recruited in Curitiba (Brazil), 249 with hgCIN and 294 without cervical lesions. Association of methylation status with hgCIN was estimated by Odds Ratio (OR) with 95% confidence interval (CI). RESULTS: The mean methylation level increased with severity of the lesion in the host and viral genes (p-trend < 0.05), with the exception of L1_II region (p-trend = 0.075). Positive association was found between methylation levels for host genes and CIN2 and CIN3 lesions respectively [CADM1: OR 4.17 (95%CI 2.03-8.56) and OR 9.54 (95%CI 4.80-18.97); MAL: OR 5.98 (95%CI 2.26-15.78) and OR 22.66 (95%CI 9.21-55.76); DAPK1: OR 3.37 (95%CI 0.93-12.13) and OR 6.74 (95%CI 1.92-23.64)]. Stronger risk estimates were found for viral genes [L1_I: OR 10.74 (95%CI 2.66-43.31) and OR 15.00 (95%CI 3.00-74.98); L1_II: OR 73.18 (95%CI 4.07-1315.94) and OR 32.50 (95%CI 3.86-273.65); L2: OR 4.73 (95%CI 1.55-14.44) and OR 10.62 (95%CI 2.60-43.39)]. The cumulative effect of the increasing number of host and viral methylated genes was associated with the risk of CIN2 and CIN3 lesions (p-trend < 0.001). CONCLUSIONS: Our results, empowered by a wide cervical sample series with a large number of hgCIN, supported the role of methylation as marker of aggressiveness.


Assuntos
Metilação de DNA , Papillomaviridae/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Adulto , Estudos de Casos e Controles , Molécula 1 de Adesão Celular/genética , Proteínas Quinases Associadas com Morte Celular/genética , Feminino , Humanos , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/genética , Gradação de Tumores , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/patologia
8.
J Med Virol ; 89(12): 2217-2223, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28771777

RESUMO

Cervical cancer is an important health issue in Latin America. Although HPV infections can have spontaneous clearance, persistence of high-risk (HR) HPV is a risk factor for cervical cancer among women and it is even higher in HIV-infected women. To determine the prevalence of HR-HPV and risk factors among HIV-infected women attending reference services for HIV/AIDS in different regions of Brazil. Cross-sectional study conducted among HIV-infected women attended at referral care centers for HIV/AIDS in nine states of Brazil. Women from 18 to 49 years that accept to participate and were not pregnant at the time of the approach were recruited for the study. The HPV screening was realized using qPCR in closed system, in vitro Diagnostic, COBAS® -HPV Roche. The cytology results were available by the Bethesda System. A total of 802(89.1%) from the selected women agreed to participate in the study. Median age was 39(Inter quartile range [IQR34-46]) years and median education was 9(IQR6-11) years. General prevalence of HR-HPV was 28.4%(228/802). HPV-16 prevalence rate was 8.1%(65/802), HPV-18 was 3.7%(30/802) and other types of HR-HPV were 23.6% (189/802). Risk factors for HR-HPV infection in the multivariate logistic regression analysis were: age ranging from 18 to 34 years (OR = 1.43[95%CI:1.18-1.75]), illicit drugs use (OR = 1.61[95%CI:1.10-2.42]) and abnormal cervical cytology (OR = 1.56[95%CI:1.34-1.81]). Results showed a prevalence rate of 28.4% of HR-HPV infection in women living with HIV in Brazil. These infections were significantly associated with having less than 35 years old, illicit drug use and abnormal cervical cytology.


Assuntos
Coinfecção , Infecções por HIV/complicações , Infecções por Papillomavirus/complicações , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Genótipo , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , HIV-1/fisiologia , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 16/fisiologia , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/isolamento & purificação , Papillomavirus Humano 18/fisiologia , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Gravidez , Prevalência , Fatores de Risco , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem
9.
Phys Rev Lett ; 118(15): 155002, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28452542

RESUMO

A potential threat to the performance of magnetically confined fusion plasmas is the problem of impurity accumulation, which causes the concentration of highly charged impurity ions to rise uncontrollably in the center of the plasma and spoil the energy confinement by excessive radiation. It has long been thought that the collisional transport of impurities in stellarators always leads to such an accumulation (if the electric field points inwards, which is usually the case), whereas tokamaks, being axisymmetric, can benefit from "temperature screening," i.e., an outward flux of impurities driven by the temperature gradient. Here it is shown, using analytical techniques supported by results from a new numerical code, that such screening can arise in stellarator plasmas, too, and indeed does so in one of the most relevant operating regimes, where the impurities are highly collisional while the bulk plasma is at low collisionality.

10.
Phys Rev Lett ; 118(25): 255001, 2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28696736

RESUMO

We analyze the dynamics of fast electrons in plasmas containing partially ionized impurity atoms, where the screening effect of bound electrons must be included. We derive analytical expressions for the deflection and slowing-down frequencies, and show that they are increased significantly compared to the results obtained with complete screening, already at subrelativistic electron energies. Furthermore, we show that the modifications to the deflection and slowing down frequencies are of equal importance in describing the runaway current evolution. Our results greatly affect fast-electron dynamics and have important implications, e.g., for the efficacy of mitigation strategies for runaway electrons in tokamak devices, and energy loss during relativistic breakdown in atmospheric discharges.

11.
Int J Cancer ; 139(12): 2812-2826, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27541373

RESUMO

We evaluated the efficacy of the human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine in preventing HPV-related disease after surgery for cervical lesions in a post-hoc analysis of the PApilloma TRIal against Cancer In young Adults (PATRICIA; NCT00122681). Healthy women aged 15-25 years were randomized (1:1) to receive vaccine or control at months 0, 1 and 6 and followed for 4 years. Women were enrolled regardless of their baseline HPV DNA status, HPV-16/18 serostatus, or cytology, but excluded if they had previous or planned colposcopy. The primary and secondary endpoints of PATRICIA have been reported previously; the present post-hoc analysis evaluated efficacy in a subset of women who underwent an excisional procedure for cervical lesions after vaccination. The main outcome was the incidence of subsequent HPV-related cervical intraepithelial neoplasia grade 2 or greater (CIN2+) 60 days or more post-surgery. Other outcomes included the incidence of HPV-related CIN1+, and vulvar or vaginal intraepithelial neoplasia (VIN/VaIN) 60 days or more post-surgery. Of the total vaccinated cohort of 18,644 women (vaccine = 9,319; control = 9,325), 454 (vaccine = 190, control = 264) underwent an excisional procedure during the trial. Efficacy 60 days or more post-surgery for a first lesion, irrespective of HPV DNA results, was 88.2% (95% CI: 14.8, 99.7) against CIN2+ and 42.6% (-21.1, 74.1) against CIN1+. No VIN was reported and one woman in each group had VaIN2+ 60 days or more post-surgery. Women who undergo surgical therapy for cervical lesions after vaccination with the HPV-16/18 vaccine may continue to benefit from vaccination, with a reduced risk of developing subsequent CIN2+.


Assuntos
Adjuvantes Imunológicos , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Displasia do Colo do Útero/etiologia , Displasia do Colo do Útero/patologia , Adolescente , Adulto , Feminino , Humanos , Gradação de Tumores , Recidiva Local de Neoplasia , Avaliação de Resultados em Cuidados de Saúde , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Vacinação , Adulto Jovem , Displasia do Colo do Útero/cirurgia
12.
Proc Natl Acad Sci U S A ; 110(35): 14438-43, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23918394

RESUMO

Maternal aggression is under the control of a wide variety of factors that prime the females for aggression or trigger the aggressive event. Maternal attacks are triggered by the perception of sensory cues from the intruder, and here we have identified a site in the hypothalamus of lactating rats that is highly responsive to the male intruder--the ventral premammillary nucleus (PMv). The PMv is heavily targeted by the medial amygdalar nucleus, and we used lesion and immediate-early gene studies to test our working hypothesis that the PMv signals the presence of a male intruder and transfers this information to the network organizing maternal aggression. PMv-lesioned dams exhibit significantly reduced maternal aggression, without affecting maternal care. The Fos analysis revealed that PMv influences the activation of hypothalamic and septal sites shown to be mobilized during maternal aggression, including the medial preoptic nucleus (likely to represent an important locus to integrate priming stimuli critical for maternal aggression), the caudal two-thirds of the hypothalamic attack area (comprising the ventrolateral part of the ventromedial hypothalamic nucleus and the adjacent tuberal region of the lateral hypothalamic area, critical for the expression of maternal aggression), and the ventral part of the anterior bed nuclei of the stria terminalis (presently discussed as being involved in controlling neuroendocrine and autonomic responses accompanying maternal aggression). These findings reveal an important role for the PMv in detecting the male intruder and how this nucleus modulates the network controlling maternal aggression.


Assuntos
Agressão , Comportamento Animal , Núcleo Hipotalâmico Ventromedial/fisiologia , Animais , Feminino , Masculino , Ratos , Ratos Long-Evans
13.
J Infect Dis ; 210(4): 517-34, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24610876

RESUMO

BACKGROUND: We examined risk of newly detected human papillomavirus (HPV) infection and cervical abnormalities in relation to HPV type 16/18 antibody levels at enrollment in PATRICIA (Papilloma Trial Against Cancer in Young Adults; NCT00122681). METHODS: Using Poisson regression, we compared risk of newly detected infection and cervical abnormalities associated with HPV-16/18 between seronegative vs seropositive women (15-25 years) in the control arm (DNA negative at baseline for the corresponding HPV type [HPV-16: n = 8193; HPV-18: n = 8463]). RESULTS: High titers of naturally acquired HPV-16 antibodies and/or linear trend for increasing antibody levels were significantly associated with lower risk of incident and persistent infection, atypical squamous cells of undetermined significance or greater (ASCUS+), and cervical intraepithelial neoplasia grades 1/2 or greater (CIN1+, CIN2+). For HPV-18, although seropositivity was associated with lower risk of ASCUS+ and CIN1+, no association between naturally acquired antibodies and infection was demonstrated. Naturally acquired HPV-16 antibody levels of 371 (95% confidence interval [CI], 242-794), 204 (95% CI, 129-480), and 480 (95% CI, 250-5756) EU/mL were associated with 90% reduction of incident infection, 6-month persistent infection, and ASCUS+, respectively. CONCLUSIONS: Naturally acquired antibodies to HPV-16, and to a lesser extent HPV-18, are associated with some reduced risk of subsequent infection and cervical abnormalities associated with the same HPV type.


Assuntos
Anticorpos Antivirais/imunologia , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/diagnóstico , Adolescente , Adulto , DNA Viral/genética , Método Duplo-Cego , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/virologia , Fatores de Risco , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia
14.
BMC Infect Dis ; 14: 551, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25927224

RESUMO

BACKGROUND: More information is needed about time between sexual initiation and human papillomavirus (HPV) infection and development of cervical precancer. METHODS: The objectives were to investigate the time between first sexual activity and detection of first cervical HPV infection or development of first cervical intraepithelial neoplasia (CIN), and associated factors in women from the double-blind, multinational, 4-year PATRICIA trial. PATRICIA enroled women aged 15-25 years with no more than 6 lifetime sexual partners. Women were randomized 1:1 to the HPV-16/18 AS04-adjuvanted vaccine or to control, but only women from the control arm who began sexual intercourse during the study or within 6 months before enrolment, and had no HPV infection detected before the recorded date of their first sexual intercourse, were included in the present analysis. The time between onset of sexual activity and detection of the first cervical HPV infection or development of the first CIN lesion was analyzed using Kaplan-Meier and univariate and multivariable Cox proportional-hazards models. RESULTS: A total of 9337 women were enroled in the control arm of PATRICIA of whom 982 fulfilled the required inclusion criteria for analysis. A cumulative total of 28%, 44%, and 62% of the subjects had HPV infection within 12, 24, and 48 months, respectively. The overall incidence rate was 27.08 per 100 person-years. The most common oncogenic types associated with 6-month persistent infection were HPV-16 (incidence rate: 2.74 per 100 person-years), HPV-51 (2.70), HPV-52 (1.66), HPV-66 (1.14), and HPV-18 (1.09). Increased infection risk was associated with more lifetime sexual partners, being single, Chlamydia trachomatis history, and duration of hormone use. CIN1+ and CIN2+ lesions were most commonly associated with HPV-16, with an overall incidence rate of 1.87 and 1.07 per 100 person-years, respectively. Previous cervical HPV infection was most strongly associated with CIN development. CONCLUSIONS: More than 25% of women were infected with HPV within 1 year of beginning sexual activity. Without underestimating the value of vaccination at older ages, our findings emphasize its importance before sexual initiation. TRIAL REGISTRATION: clinicaltrials.gov: NCT00122681 .


Assuntos
Infecções por Papillomavirus/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Comportamento Sexual/estatística & dados numéricos , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adolescente , Adulto , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Fatores de Risco , Parceiros Sexuais , Espanha/epidemiologia , Fatores de Tempo , Adulto Jovem
15.
J Infect Dis ; 208(9): 1391-6, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24092907

RESUMO

BACKGROUND: Public Health England has reported a decrease of up to 20.8% in new diagnoses of external genital warts (GWs) among women aged <19 years since the national vaccination program with the human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine began in 2008. A post hoc analysis of the phase III PATRICIA (PApilloma TRIal against Cancer In young Adults) trial (NCT00122681) was performed to ascertain whether protection against low-risk HPV types was apparent. METHODS: Vaccine efficacy (VE) at 48 months was assessed against 6-month persistent infection (6MPI) with low-risk HPV types in the total vaccinated cohort (TVC) and in the TVC naive (for 25 HPV types tested) populations. RESULTS: In the TVC naive cohort, VE against 6MPI (95% confidence interval) was 34.5% (11.3 to 51.8) for HPV-6/11, 34.9% (9.1 to 53.7) for HPV-6, 30.3% (-45.0 to 67.5) for HPV-11, and 49.5% (21.0 to 68.3) for HPV-74. CONCLUSIONS: The HPV-16/18 AS04-adjuvanted vaccine appears to have moderate efficacy against persistent infections with a number of low-risk HPV types (HPV-6/11/74), which are responsible for the majority of external GWs, and recently, antibody and cell-mediated immune response to HPV-6/11 have been observed. These findings may help to explain the decrease in external GW diagnoses seen in England.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Hidróxido de Alumínio/administração & dosagem , Condiloma Acuminado/prevenção & controle , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Lipídeo A/análogos & derivados , Vacinação , Ensaios Clínicos Fase III como Assunto , Condiloma Acuminado/epidemiologia , Condiloma Acuminado/imunologia , Método Duplo-Cego , Feminino , Papillomavirus Humano 6/imunologia , Humanos , Incidência , Achados Incidentais , Lipídeo A/administração & dosagem , Estudos Multicêntricos como Assunto , Vacinas contra Papillomavirus , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
16.
Neurosci Biobehav Rev ; 162: 105732, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797459

RESUMO

Anxiety is a complex phenomenon: Its eliciting stimuli and circumstances, component behaviors, and functional consequences are only slowly coming to be understood. Here, we examine defense systems from field studies; laboratory studies focusing on experimental analyses of behavior; and, the fear conditioning literature, with a focus on the role of uncertainty in promoting an anxiety pattern that involves high rates of stimulus generalization and resistance to extinction. Respectively, these different areas provide information on evolved elicitors of defense (field studies); outline a defense system focused on obtaining information about uncertain threat (ethoexperimental analyses); and, provide a simple, well-researched, easily measured paradigm for analysis of nonassociative stress-enhanced fear conditioning (the SEFL). Results suggest that all of these-each of which is responsive to uncertainty-play multiple and interactive roles in anxiety. Brain system findings for some relevant models are reviewed, with suggestions that further analyses of current models may be capable of providing a great deal of additional information about these complex interactions and their underlying biology.


Assuntos
Ansiedade , Evolução Biológica , Encéfalo , Incerteza , Humanos , Ansiedade/fisiopatologia , Animais , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Medo/fisiologia , Neurobiologia
17.
Curr Biol ; 34(13): R625-R628, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981427

RESUMO

The dorsal periaqueductal gray (dPAG) contains a tonically GABAergic network controlling defensive responses. Determining how this intrinsic dPAG inhibitory circuit functions might provide critical insights into how anti-predatory responses are organized.


Assuntos
Substância Cinzenta Periaquedutal , Comportamento Predatório , Animais , Comportamento Predatório/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Reação de Fuga/fisiologia
18.
PeerJ ; 12: e17481, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881857

RESUMO

Background: COVID-19 is an infectious pathology that shows vascular changes during pregnancy, as well as in the placentas. The main objectives of this study were to estimate the prevalence and the risk factors for preeclampsia in hospitalized pregnant women with COVID-19. As well as comparing maternal and perinatal outcomes in hospitalized pregnant women with COVID-19 and preeclampsia with those without preeclampsia. Methods: Prospective cohort study of 100 hospitalized pregnant women from two tertiary hospitals, diagnosed with COVID-19, and divided into two groups: PE+ group (pregnant women with COVID-19 and preeclampsia) and PE- group (pregnant women with COVID-19 without preeclampsia). These pregnant women had prevalence, risk factors, maternal and perinatal data analyzed. Results: The prevalence of preeclampsia was 11%. Severe COVID-19 was the main risk factor for preeclampsia (OR = 8.18 [CI 1.53-43.52]), as well as fetal growth restriction was the main perinatal outcome (OR = 8.90 [CI 1.52-38.4]). Comorbidities were more frequent in the PE+ group (63.6% vs 31.5%, p = 0.03), as well as prematurity (81.8% vs 41.6%, p = 0.02), low birth weight (63.6% vs 24.7%, p = 0.01), and the need for neonatal intensive care admission of the newborn (63.6% vs 27.0%, p = 0.03). Pregnant women with PE had twice as long a length of stay in the intensive care unit (RR = 2.35 [CI 1.34-4.14]). Although maternal mortality was more frequent among pregnant women with PE, it was not statistically significant. Conclusions: Prevalence of preeclampsia in hospitalized pregnant women with COVID-19 was 11%. Severe COVID-19 was the main risk factor for preeclampsia and associated comorbidities increased the risk for developing preeclampsia. Long length of stay in the intensive care unit was the main maternal outcome and fetal growth restriction was the main perinatal outcome of preeclampsia.


Assuntos
COVID-19 , Pré-Eclâmpsia , Complicações Infecciosas na Gravidez , Resultado da Gravidez , SARS-CoV-2 , Centros de Atenção Terciária , Humanos , Gravidez , Feminino , Pré-Eclâmpsia/epidemiologia , COVID-19/epidemiologia , COVID-19/mortalidade , Brasil/epidemiologia , Estudos Prospectivos , Adulto , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/virologia , Fatores de Risco , Resultado da Gravidez/epidemiologia , Prevalência , Recém-Nascido , Retardo do Crescimento Fetal/epidemiologia , Retardo do Crescimento Fetal/virologia , Comorbidade
19.
Curr Biol ; 34(12): 2657-2671.e7, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38810639

RESUMO

Animals need to detect threats, initiate defensive responses, and, in parallel, remember where the threat occurred to avoid the possibility of re-encountering it. By probing animals capable of detecting and avoiding a shock-related threatening location, we were able to reveal a septo-hippocampal-hypothalamic circuit that is also engaged in ethological threats, including predatory and social threats. Photometry analysis focusing on the dorsal premammillary nucleus (PMd), a critical interface of this circuit, showed that in freely tested animals, the nucleus appears ideal to work as a threat detector to sense dynamic changes under threatening conditions as the animal approaches and avoids the threatening source. We also found that PMd chemogenetic silencing impaired defensive responses by causing a failure of threat detection rather than a direct influence on any behavioral responses and, at the same time, updated fear memory to a low-threat condition. Optogenetic silencing of the main PMd targets, namely the periaqueductal gray and anterior medial thalamus, showed that the projection to the periaqueductal gray influences both defensive responses and, to a lesser degree, contextual memory, whereas the projection to the anterior medial thalamus has a stronger influence on memory processes. Our results are important for understanding how animals deal with the threat imminence continuum, revealing a circuit that is engaged in threat detection and that, at the same time, serves to update the memory process to accommodate changes under threatening conditions.


Assuntos
Medo , Hipocampo , Memória , Animais , Medo/fisiologia , Memória/fisiologia , Masculino , Hipocampo/fisiologia , Vias Neurais/fisiologia , Hipotálamo/fisiologia , Optogenética , Ratos/fisiologia
20.
Lancet Oncol ; 13(1): 89-99, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22075171

RESUMO

BACKGROUND: Cervical intraepithelial neoplasia grade 2 or greater (CIN2+) is the surrogate endpoint used in licensure trials of human papillomavirus (HPV) vaccines. Vaccine efficacy against CIN3+, the immediate precursor to invasive cervical cancer, is more difficult to measure because of its lower incidence, but provides the most stringent evidence of potential cancer prevention. We report vaccine efficacy against CIN3+ and adenocarcinoma in situ (AIS) in the end-of-study analysis of PATRICIA (PApilloma TRIal against Cancer In young Adults). METHODS: Healthy women aged 15-25 years with no more than six lifetime sexual partners were included in PATRICIA, irrespective of their baseline HPV DNA status, HPV-16 or HPV-18 serostatus, or cytology. Women were randomly assigned (1:1) to receive an HPV-16/18 AS04-adjuvanted vaccine or a control hepatitis A vaccine via an internet-based central randomisation system using a minimisation algorithm to account for age ranges and study sites. The patients and study investigators were masked to allocated vaccine. The primary endpoint of PATRICIA has been reported previously. In the present end-of-study analysis, we focus on CIN3+ and AIS in the populations of most clinical interest, the total vaccinated cohort (TVC) and the TVC-naive. The TVC comprised all women who received at least one vaccine dose, approximating catch-up populations and including sexually active women (vaccine n=9319; control=9325). The TVC-naive comprised women with no evidence of oncogenic HPV infection at baseline, approximating early adolescent HPV exposure (vaccine n=5824; control=5820). This study is registered with ClinicalTrials.gov, number NCT00122681. FINDINGS: Vaccine efficacy against CIN3+ associated with HPV-16/18 was 100% (95% CI 85·5-100) in the TVC-naive and 45·7% (22·9-62·2) in the TVC. Vaccine efficacy against all CIN3+ (irrespective of HPV type in the lesion and including lesions with no HPV DNA detected) was 93·2% (78·9-98·7) in the TVC-naive and 45·6% (28·8-58·7) in the TVC. In the TVC-naive, vaccine efficacy against all CIN3+ was higher than 90% in all age groups. In the TVC, vaccine efficacy against all CIN3+ and CIN3+ associated with HPV-16/18 was highest in the 15-17 year age group and progressively decreased in the 18-20 year and 21-25 year age groups. Vaccine efficacy against all AIS was 100% (31·0-100) and 76·9% (16·0-95·8) in the TVC-naive and TVC, respectively. Serious adverse events occurred in 835 (9·0%) and 829 (8·9%) women in the vaccine and control groups, respectively; only ten events (0·1%) and five events (0·1%), respectively, were considered to be related to vaccination. INTERPRETATION: PATRICIA end-of-study results show excellent vaccine efficacy against CIN3+ and AIS irrespective of HPV DNA in the lesion. Population-based vaccination that incorporates the HPV-16/18 vaccine and high coverage of early adolescents might have the potential to substantially reduce the incidence of cervical cancer. FUNDING: GlaxoSmithKline Biologicals.


Assuntos
Adenocarcinoma/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Hidróxido de Alumínio/administração & dosagem , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/imunologia , Lipídeo A/análogos & derivados , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Displasia do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/prevenção & controle , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/virologia , Adolescente , Adulto , Fatores Etários , Ásia , Austrália , DNA Viral/análise , Método Duplo-Cego , Europa (Continente) , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Lipídeo A/administração & dosagem , Gradação de Tumores , América do Norte , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/virologia , América do Sul , Fatores de Tempo , Resultado do Tratamento , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
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