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1.
Anim Genet ; 52(1): 32-46, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33191532

RESUMO

This study aimed to assess the predictive ability of different machine learning (ML) methods for genomic prediction of reproductive traits in Nellore cattle. The studied traits were age at first calving (AFC), scrotal circumference (SC), early pregnancy (EP) and stayability (STAY). The numbers of genotyped animals and SNP markers available were 2342 and 321 419 (AFC), 4671 and 309 486 (SC), 2681 and 319 619 (STAY) and 3356 and 319 108 (EP). Predictive ability of support vector regression (SVR), Bayesian regularized artificial neural network (BRANN) and random forest (RF) were compared with results obtained using parametric models (genomic best linear unbiased predictor, GBLUP, and Bayesian least absolute shrinkage and selection operator, BLASSO). A 5-fold cross-validation strategy was performed and the average prediction accuracy (ACC) and mean squared errors (MSE) were computed. The ACC was defined as the linear correlation between predicted and observed breeding values for categorical traits (EP and STAY) and as the correlation between predicted and observed adjusted phenotypes divided by the square root of the estimated heritability for continuous traits (AFC and SC). The average ACC varied from low to moderate depending on the trait and model under consideration, ranging between 0.56 and 0.63 (AFC), 0.27 and 0.36 (SC), 0.57 and 0.67 (EP), and 0.52 and 0.62 (STAY). SVR provided slightly better accuracies than the parametric models for all traits, increasing the prediction accuracy for AFC to around 6.3 and 4.8% compared with GBLUP and BLASSO respectively. Likewise, there was an increase of 8.3% for SC, 4.5% for EP and 4.8% for STAY, comparing SVR with both GBLUP and BLASSO. In contrast, the RF and BRANN did not present competitive predictive ability compared with the parametric models. The results indicate that SVR is a suitable method for genome-enabled prediction of reproductive traits in Nellore cattle. Further, the optimal kernel bandwidth parameter in the SVR model was trait-dependent, thus, a fine-tuning for this hyper-parameter in the training phase is crucial.


Assuntos
Bovinos/genética , Aprendizado de Máquina , Modelos Genéticos , Reprodução/genética , Animais , Brasil , Feminino , Genômica , Fenótipo , Polimorfismo de Nucleotídeo Único , Gravidez
2.
Public Health ; 179: 45-50, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726400

RESUMO

OBJECTIVES: The objective of this study was to estimate mortality risk among women exposed to violence in Brazil using population-based data. STUDY DESIGN: This study used a linked database containing nearly 800,000 violence (against women) notifications and 16,500 associated deaths over the period 2011-2016. METHODS: Aggregate age-standardized population-based rates of mortality were built to estimate risk ratios (RRs) at the national and state level, and for different forms of violence and causes of death, as well as type of offender involved, and across various characteristics of the women. RRs compared the rate of mortality among women exposed to violence with that in the general population of women - excess mortality due to violence was also derived from this comparison. The analysis was divided into two time periods (2011-13 and 2014-16). RESULTS: During 2014-16, women exposed to violence had an estimated mortality risk that was 8.3 [95% confidence interval (CI): 8.2-8.5] times higher than that of the general woman population, and an estimated 100 women died on a weekly basis as a direct or indirect consequence of exposure to violence. Higher (all-cause) mortality risk was associated with physical violence and violence that involved repetition and that was self-inflicted. The risk of mortality increased when the cause of death involved external causes (RR: 51.2, 95% CI: 49.6-52.8). When death was attributable to (i) non-communicable diseases and (ii) communicable, maternal, neonatal, and nutritional diseases, the risk was 5.4 [95% CI: 5.3-5.6] and 6.7 [95% CI: 6.1-7.2] times, respectively. Women at greatest (all-cause) mortality risk include white and multiracial (parda) and single women in the age group 10-29 years, who live in the northeast part of the country. When the offender was a partner/ex., women aged 10-19 years showed the greatest (all-cause) mortality risk at 16.9 [95% CI: 13.9-19.8] times. Higher risk was also observed within the age group 30-59 years when death was attributable to external causes (RR: 74.6, 95% CI: 71.3-77.9). For younger women and girls, there was a clear gradient in (all-cause) mortality risk, with those living in the poorest municipalities at greater risk. Age-specific mortality risk also showed significant variation within and across states. CONCLUSIONS: This analysis suggests that most women exposed to violence will likely experience an increased risk of mortality, regardless of her place of residence, age group, racial/ethnic background, marital status situation, and socio-economic status. The estimated RRs are only an approximation given the design of this analysis and should be interpreted with caution.


Assuntos
Maus-Tratos Conjugais/mortalidade , Violência/estatística & dados numéricos , Adolescente , Adulto , Brasil/epidemiologia , Causas de Morte , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Doenças não Transmissíveis , Fatores de Risco , Pessoa Solteira , Maus-Tratos Conjugais/psicologia , Violência/psicologia , Adulto Jovem
3.
Mol Psychiatry ; 17(11): 1077-85, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21876543

RESUMO

Mutations in the human FOXP2 gene cause impaired speech development and linguistic deficits, which have been best characterised in a large pedigree called the KE family. The encoded protein is highly conserved in many vertebrates and is expressed in homologous brain regions required for sensorimotor integration and motor-skill learning, in particular corticostriatal circuits. Independent studies in multiple species suggest that the striatum is a key site of FOXP2 action. Here, we used in vivo recordings in awake-behaving mice to investigate the effects of the KE-family mutation on the function of striatal circuits during motor-skill learning. We uncovered abnormally high ongoing striatal activity in mice carrying an identical mutation to that of the KE family. Furthermore, there were dramatic alterations in striatal plasticity during the acquisition of a motor skill, with most neurons in mutants showing negative modulation of firing rate, starkly contrasting with the predominantly positive modulation seen in control animals. We also observed striking changes in the temporal coordination of striatal firing during motor-skill learning in mutants. Our results indicate that FOXP2 is critical for the function of striatal circuits in vivo, which are important not only for speech but also for other striatal-dependent skills.


Assuntos
Corpo Estriado/fisiologia , Fatores de Transcrição Forkhead/fisiologia , Aprendizagem/fisiologia , Plasticidade Neuronal/genética , Proteínas Repressoras/fisiologia , Potenciais de Ação/fisiologia , Animais , Fatores de Transcrição Forkhead/genética , Camundongos , Camundongos Mutantes , Destreza Motora/fisiologia , Inibição Neural/fisiologia , Proteínas Repressoras/genética , Teste de Desempenho do Rota-Rod/métodos
4.
Nat Genet ; 27(4): 399-405, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11279521

RESUMO

Neurofibromatosis type 1 (NF1) is a commonly inherited autosomal dominant disorder. Previous studies indicated that mice homozygous for a null mutation in Nf1 exhibit mid-gestation lethality, whereas heterozygous mice have an increased predisposition to tumors and learning impairments. Here we show that mice lacking the alternatively spliced exon 23a, which modifies the GTPase-activating protein (GAP) domain of Nf1, are viable and physically normal, and do not have an increased tumor predisposition, but show specific learning impairments. Our findings have implications for the development of a treatment for the learning disabilities associated with NF1 and indicate that the GAP domain of NF1 modulates learning and memory.


Assuntos
Éxons , Predisposição Genética para Doença , Deficiências da Aprendizagem/genética , Neoplasias Experimentais/genética , Animais , Sequência de Bases , Primers do DNA , Genes da Neurofibromatose 1 , Camundongos , Neurofibromatose 1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
bioRxiv ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37790555

RESUMO

Reaches are complex movements that are critical for survival, and encompass the control of different aspects such as direction, speed, and endpoint precision. Complex movements have been postulated to be learned and controlled through distributed motor networks, of which the thalamus is a highly connected node. Still, the role of different thalamic circuits in learning and controlling specific aspects of reaches has not been investigated. We report dissociable roles of two distinct thalamic nuclei - the parafascicular (Pf) and ventroanterior/ventrolateral (VAL) nuclei - in the refinement of spatial target reaches in mice. Using 2-photon calcium imaging in a head-fixed joystick task where mice learned to reach to a target in space, we found that glutamatergic neurons in both areas were most active during reaches early in learning. Reach-related activity in both areas decreased late in learning, as movement direction was refined and reaches increased in accuracy. Furthermore, the population dynamics of Pf, but not VAL, covaried in different subspaces in early and late learning, but eventually stabilized in late learning. The neural activity in Pf, but not VAL, encoded the direction of reaches in early but not late learning. Accordingly, bilateral lesions of Pf before, but not after learning, strongly and specifically impaired the refinement of reach direction. VAL lesions did not impact direction refinement, but instead resulted in increased speed and target overshoot. Our findings provide new evidence that the thalamus is a critical motor node in the learning and control of reaching movements, with specific subnuclei controlling distinct aspects of the reach early in learning.

6.
Exp Oncol ; 45(1): 107-119, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37417276

RESUMO

BACKGROUND: Skeletal muscle wasting is a common phenotypic feature of several types of cancer, and it is associated with functional impairment, respiratory complications, and fatigue. However, equivocal evidence remains regarding the impact of cancer-induced muscle wasting on the different fiber types. AIM: The aim of this study was to investigate the impact of urothelial carcinoma induced in mice on the histomorphometric features and collagen deposition in different skeletal muscles. MATERIALS AND METHODS: Thirteen ICR (CD1) male mice were randomly assigned into two groups: exposed to 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in drinking water for 12 weeks, plus 8 weeks of tap water (BBN, n = 8) or with access to tap water for 20 weeks (CONT, n = 5). Tibialis anterior, soleus, and diaphragm muscles were collected from all animals. For cross-sectional area and myonuclear domain analysis, muscle sections were stained with hematoxylin and eosin, and for collagen deposition assessment, muscle sections were stained with picrosirius red. RESULTS: All animals from the BBN group developed urothelial preneoplastic and neoplastic lesions, and the tibialis anterior from these animals presented a reduced cross-sectional area (p < 0.001), with a decreased proportion of fibers with a higher cross-sectional area, increased collagen deposition (p = 0.017), and higher myonuclear domain (p = 0.031). BBN mice also showed a higher myonuclear domain in the diaphragm (p = 0.015). CONCLUSION: Urothelial carcinoma induced muscle wasting of the tibialis anterior, expressed by a decreased cross-sectional area, higher infiltration of fibrotic tissue, and increased myonuclear domain, which also increased in the diaphragm, suggesting that fast glycolytic muscle fibers are more susceptible to be affected by cancer development.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Camundongos , Masculino , Animais , Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/patologia , Camundongos Endogâmicos ICR , Músculo Esquelético/patologia , Músculo Esquelético/fisiologia , Fibras Musculares de Contração Rápida/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia
7.
bioRxiv ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37214823

RESUMO

The brain can learn to generate actions, such as reaching to a target, using different movement strategies. Understanding how different variables bias which strategies are learned to produce such a reach is important for our understanding of the neural bases of movement. Here we introduce a novel spatial forelimb target task in which perched head-fixed mice learn to reach to a circular target area from a set start position using a joystick. These reaches can be achieved by learning to move into a specific direction or to a specific endpoint location. We find that mice gradually learn to successfully reach the covert target. With time, they refine their initially exploratory complex joystick trajectories into controlled targeted reaches. The execution of these controlled reaches depends on the sensorimotor cortex. Using a probe test with shifting start positions, we show that individual mice learned to use strategies biased to either direction or endpoint-based movements. The degree of endpoint learning bias was correlated with the spatial directional variability with which the workspace was explored early in training. Furthermore, we demonstrate that reinforcement learning model agents exhibit a similar correlation between directional variability during training and learned strategy. These results provide evidence that individual exploratory behavior during training biases the control strategies that mice use to perform forelimb covert target reaches.

8.
IEEE Trans Syst Man Cybern B Cybern ; 42(4): 1072-82, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22389153

RESUMO

The human eye is sensitive to visible light. Increasing illumination on the eye causes the pupil of the eye to contract, while decreasing illumination causes the pupil to dilate. Visible light causes specular reflections inside the iris ring. On the other hand, the human retina is less sensitive to near infra-red (NIR) radiation in the wavelength range from 800 nm to 1400 nm, but iris detail can still be imaged with NIR illumination. In order to measure the dynamic movement of the human pupil and iris while keeping the light-induced reflexes from affecting the quality of the digitalized image, this paper describes a device based on the consensual reflex. This biological phenomenon contracts and dilates the two pupils synchronously when illuminating one of the eyes by visible light. In this paper, we propose to capture images of the pupil of one eye using NIR illumination while illuminating the other eye using a visible-light pulse. This new approach extracts iris features called "dynamic features (DFs)." This innovative methodology proposes the extraction of information about the way the human eye reacts to light, and to use such information for biometric recognition purposes. The results demonstrate that these features are discriminating features, and, even using the Euclidean distance measure, an average accuracy of recognition of 99.1% was obtained. The proposed methodology has the potential to be "fraud-proof," because these DFs can only be extracted from living irises.

9.
Vet Pathol ; 48(2): 427-32, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20861495

RESUMO

Canine renal cell carcinomas (RCCs) are uncommon aggressive tumors that occur mainly in middle-aged male dogs. Their histologic classification bears no relationship with prognosis, and little information is available concerning their immunohistochemical properties. In this retrospective study, formalin-fixed, paraffin-embedded tissues from 13 canine RCCs were retrieved from the archives, classified histologically, and evaluated immunohistochemically. The dogs were 7 males and 6 females (1 spayed) of 10 different breeds, averaging 8 years in age. The tumors were classified as papillary, tubulopapillary, papillary-cystic, solid, or sarcomatoid. All 13 tumors were immunohistochemically positive for uromodulin, 12 for c-KIT, 11 for vimentin, 9 for wide-spectrum-screening cytokeratins, 7 for cytokeratins AE1/AE3 and carcinoembryonic antigen, 4 for cytokeratins CAM 5.2, and 3 for CD10. All 3 solid RCCs expressed vimentin, c-KIT, and carcinoembryonic antigen and were negative for cytokeratins. All 7 papillary and tubulopapillary tumors expressed vimentin; 6 (86%), cytokeratins; and 6 (86%), c-KIT. Both papillary-cystic RCCs were positive for cytokeratins and c-KIT and negative for vimentin. These results indicate that the different histologic types of RCC have characteristic immunohistochemical profiles and that c-KIT may be involved in the pathogenesis of canine RCC.


Assuntos
Carcinoma de Células Renais/veterinária , Doenças do Cão/patologia , Neoplasias Renais/veterinária , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/patologia , Cães , Feminino , Imuno-Histoquímica/veterinária , Neoplasias Renais/classificação , Neoplasias Renais/patologia , Masculino , Proteínas Proto-Oncogênicas c-kit/metabolismo , Estudos Retrospectivos
11.
Pulmonology ; 27(6): 529-562, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33931378

RESUMO

INTRODUCTION: The COVID-19 pandemic originated in China and within about 4 months affected individuals all over the world. One of the limitations to the management of the COVID-19 is the diagnostic imaging to evaluate lung impairment and the patients' clinical evolution, mainly, in more severe cases that require admission into the intensive care unit. Among image examinations, lung ultrasound (LU) might be a useful tool to employ in the treatment of such patients. METHODS: A survey was carried out on PubMed to locate studies using the descriptors: ((Lung ultrasound OR ultrasound OR lung ultrasonography OR lung US) AND (coronavirus disease-19 OR coronavirus disease OR corona virus OR COVID-19 OR COVID19 OR SARS-CoV-2)). The period covered by the search was November 2019 to October 2020 and the papers selected reported LU in COVID-19. RESULTS: Forty-three studies were selected to produce this systematic review. The main LU findings referred to the presence of focal, multifocal and/or confluent B lines and the presence of pleural irregularities. CONCLUSIONS: The use of LU in the evaluation of patients with COVID-19 should be encouraged due to its intrinsic characteristics; a low cost, radiation free, practical method, with easy to sanitize equipment, which facilitates structural evaluation of lung damage caused by SARS-CoV-2. With the increase in the number of studies and the use of ultrasound scans, LU has been shown as a useful tool to evaluate progression, therapeutic response and follow-up of pulmonary disease in the patients with COVID-19.


Assuntos
COVID-19 , Pulmão , Ultrassonografia , COVID-19/diagnóstico por imagem , Teste para COVID-19 , Progressão da Doença , Humanos , Pulmão/diagnóstico por imagem , Pandemias
12.
Med Hypotheses ; 144: 109979, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32570162

RESUMO

Atheromatous plaques occurring in large arteries are common and life-threatening lesions. Multiple factors are involved in the pathogenesis of atheromatous plaques, such as hyperlipidaemia and hypercholesterolaemia, high blood pressure and chronic systemic inflammation. Recent findings have suggested that infection with high-risk human papillomavirus (HPV) may increase the risk of developing atheromatous plaques. However, HPV is considered a tissue-specific virus with a strong tropism towards squamous epithelial cells, and the mechanisms whereby it may promote the development of atheromas remain unclear. Here, we propose a connecting hypothesis to explain the possible causative role of HPV on atheroma development. We hypothesize that HPV infection may promote atheroma formation in infected patients by enhancing systemic inflammation or by directly targeting blood vessels via nucleic acids carried by extracellular vesicles such as exosomes. The pro-inflammatory effects of HPV and the release of extracellular vesicles by HPV-transformed cells are well documented in scientific literature. Possible experimental approaches to test this hypothesis are also discussed, especially experiments employing transgenic mice bearing HPV16 transgenes. If correct, this hypothesis would have major implications for the prevention of cardiovascular diseases, especially due to the preventable nature of HPV infection through vaccination.


Assuntos
Aterosclerose , Infecções por Papillomavirus , Animais , Papillomavirus Humano 16 , Humanos , Camundongos , Camundongos Transgênicos , Infecções por Papillomavirus/complicações , Fatores de Risco
13.
Int J STD AIDS ; 20(12): 869-75, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19948903

RESUMO

Research shows that (1) greater use of immature psychological defence mechanisms (associated with psychopathology) is associated with lesser orgasmic consistency from penile-vaginal intercourse (PVI), but greater frequency of other sexual behaviours and greater condom use for PVI, and (2) unlike the vectors of receptive anal intercourse and punctures, HIV acquisition during PVI is extremely unlikely in reasonably healthy persons. However, the relationship between overestimation of AIDS deaths due to 'heterosexual transmission' (often misunderstood as only PVI), sexual behaviour and mental health has been lacking. Two hundred and twenty-one Scottish women completed the Defense Style Questionnaire, reported past month frequencies of their various sexual activities, and estimated the total number of women who died from AIDS in Scotland nominally as a result of heterosexual transmission in the UK from a partner not known to be an injecting drug user, bisexual or infected through transfusion. The average respondent overestimated by 226,000%. Women providing lower estimates were less likely to use immature psychological defences, and had a lower frequency of orgasms from clitoral masturbation during PVI and from vibrator use. The results indicate that those who perceive 'heterosexual transmission' led to many AIDS deaths have poorer psychological functioning, and might be less able to appreciate PVI.


Assuntos
Síndrome da Imunodeficiência Adquirida/mortalidade , Coito/psicologia , Mecanismos de Defesa , Heterossexualidade , Orgasmo , Comportamento Sexual , Síndrome da Imunodeficiência Adquirida/transmissão , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Atitude Frente a Saúde , Clitóris , Feminino , Humanos , Masculino , Masturbação , Inventário de Personalidade , Risco , Escócia , Inquéritos e Questionários , Adulto Jovem
14.
Nat Neurosci ; 4(12): 1238-43, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11713472

RESUMO

Here we introduce a strategy in which pharmacology is used to induce the effects of recessive mutations. For example, mice heterozygous for a null mutation of the K-ras gene (K-ras+/-) show normal hippocampal mitogen-activated protein kinase (MAPK) activation, long-term potentiation (LTP) and contextual conditioning. However, a dose of a mitogen-activated/extracellular-signal-regulated kinase (MEK) inhibitor, ineffective in wild-type controls, blocks MAPK activation, LTP and contextual learning in K-ras+/- mutants. These indicate that K-Ras/MEK/MAPK signaling is critical in synaptic and behavioral plasticity. A subthreshold dose of NMDA receptor antagonists triggered a contextual learning deficit in mice heterozygous for a point mutation (T286A) in the alphaCaMKII gene, but not in K-ras+/- mutants, demonstrating the specificity of the synergistic interaction between the MEK inhibitor and the K-ras+/- mutation. This pharmacogenetic approach combines the high temporal specificity that pharmacological manipulations offer, with the molecular specificity of genetic disruptions.


Assuntos
Genes ras/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Memória/efeitos dos fármacos , Mutação/efeitos dos fármacos , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Axônios/efeitos dos fármacos , Axônios/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Quinases Dependentes de Cálcio-Calmodulina/deficiência , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Medo/efeitos dos fármacos , Medo/fisiologia , Feminino , Genes ras/fisiologia , Heterozigoto , Hipocampo/metabolismo , Aprendizagem/fisiologia , Potenciação de Longa Duração/fisiologia , MAP Quinase Quinase 1 , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Memória/fisiologia , Camundongos , Camundongos Knockout , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação/fisiologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo
15.
Biomed Pharmacother ; 104: 275-279, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29775895

RESUMO

Infection with high-risk human papillomavirus (HPV), most often HPV16, is associated with the development of anogenital and oropharyngeal cancers. Recently, ozone therapy was reported to have considerable efficacy against rabbit VX2 tumors, induced by the cottontail rabbit papillomavirus. The present study aims to determine whether similar results can be obtained in HPV16-transgenic mice, possibly paving the way for new therapeutic options against HPV-induced cancers. HPV16-transgenic and wild-type, female, 20 weeks-old mice were injected intraperitoneally with medical O3/O2 (80░mL/kg, at O3 50░µg/mL), once a day, for 5 consecutive days. The animals were sacrificed at 25 weeks-old, and skin samples were analyzed histologically to study tumour progression. Blood and internal organ samples were used to study toxicological parameters. 85.7% of untreated transgenic mice showed dysplastic skin lesions, compared with 28.6% of O3-treated mice. This was associated with a marked reduction of dermal inflammation associated with those lesions. No significant changes were observed in any toxicological parameters. These preliminary results support the hypothesis that O3 therapy is effective against papillomavirus-induced lesions, particularly against those induced by the most common high-risk virus, HPV16. Further studies are needed to confirm the mechanisms underlying these effects.


Assuntos
Papillomavirus Humano 16/patogenicidade , Neoplasias/tratamento farmacológico , Ozônio/farmacologia , Dermatopatias/tratamento farmacológico , Animais , Progressão da Doença , Feminino , Camundongos , Camundongos Transgênicos , Neoplasias/virologia , Infecções por Papillomavirus/complicações , Coelhos , Pele/efeitos dos fármacos , Pele/virologia , Dermatopatias/virologia , Resultado do Tratamento
16.
Life Sci ; 212: 168-175, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30292829

RESUMO

Liver cirrhosis is associated with a wide range of cardiovascular abnormalities including hyperdynamic circulation and cirrhotic cardiomyopathy. The pathogenic mechanisms of these cardiovascular changes are multifactorial and include vascular dysregulations. AIM: The present study tested the hypothesis that the systemic vascular hyporesponsiveness in thioacetamide (TAA)-induced liver injury model is dependent on nitric oxide (NO) and cyclooxygenase (COX) derivatives. MAIN METHODS: Wistar rats were treated with TAA for eight weeks to induce liver injury. KEY FINDINGS: The maximal contractile response in concentration-effect curves to phenylephrine was decreased in aorta from TAA-treated rats, but no differences were found in aorta without endothelium, suggesting an endothelium-dependent mechanism in decreased contractile response. There was no difference in the contractile response with and without L-NAME (N(ω)-nitro-l-arginine methyl ester) in rats with liver injury, showing that the TAA treatment impairs NO synthesis. Pre-incubation of the aorta with indomethacin, a COX-inhibitor, normalized the reduced contractile response to phenylephrine in arteries from TAA group. Also, COX-2 and iNOS (inducible nitric oxide syntase) protein expression was increased in aorta from TAA group compared to control group. Animals submitted to TAA treatment had a reduction in systolic blood pressure. Our findings demonstrated that liver injury induced by TAA caused a decrease in aortic contractile response by a COX-dependent mechanism but not by NO release. Also, it was demonstrated an inflammatory process in the aorta of TAA-treated rats by increased expression of COX-2 and iNOS. SIGNIFICANCE: Therefore, there is an essential contribution of COX-2 activation in extra-hepatic vascular dysfunction and inflammation present in cirrhosis induced by TAA.


Assuntos
Aorta Torácica/patologia , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Ciclo-Oxigenase 2/metabolismo , Endotélio Vascular/patologia , Tioacetamida/toxicidade , Doenças Vasculares/etiologia , Animais , Aorta Torácica/enzimologia , Pressão Sanguínea , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Endotélio Vascular/enzimologia , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar , Doenças Vasculares/enzimologia
17.
Food Funct ; 9(8): 4419-4428, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30066000

RESUMO

Cancers induced by human papillomavirus (HPV) infection remain a significant public health threat, fueling the study of new therapies. Laurel (Laurus nobilis) compounds and extracts recently showed in vitro activity against HPV-transformed cell lines. This work aims to evaluate the in vivo efficacy and hepatic toxicity of a laurel extract in a transgenic mouse model of HPV16-induced cancer. The extract was administered in drinking water (20 mg per animal per day) for three consecutive weeks, using four experimental groups (n = 10) (group I: HPV16-/- without treatment, group II: treated HPV16-/-, group III: HPV16+/- without treatment and group IV: treated HPV16+/-). Following the treatment period, animals were sacrificed and skin samples were used to classify skin lesions histologically. Toxicological parameters included hematological and biochemical blood markers, splenic and hepatic histology and hepatic oxidative stress. The extract did not prevent the progression of HPV16-induced cutaneous lesions in this model. The treated wild-type animals showed mild hepatitis, while transgenic animals suffered weight loss. However, there were no changes concerning hematological, biochemical and hepatic oxidative stress markers.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Papillomavirus Humano 16/fisiologia , Laurus/química , Infecções por Papillomavirus/virologia , Extratos Vegetais/toxicidade , Neoplasias do Colo do Útero/virologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Feminino , Papillomavirus Humano 16/genética , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
18.
Genes Brain Behav ; 6(4): 314-20, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16848782

RESUMO

To survive, animals must constantly update the internal value of stimuli they encounter; a process referred to as incentive learning. Although there have been many studies investigating whether dopamine is necessary for reward, or for the association between stimuli and actions with rewards, less is known about the role of dopamine in the updating of the internal value of stimuli per se. We used a single-bottle forced-choice task to investigate the role of dopamine in learning the value of tastants. We show that dopamine transporter knock-out mice (DAT-KO), which have constitutively elevated dopamine levels, develop a more positive bias towards a hedonically positive tastant (sucrose 400 mM) than their wild-type littermates. Furthermore, when compared to wild-type littermates, DAT-KO mice develop a less negative bias towards a hedonically negative tastant (quinine HCl 10 mM). Importantly, these effects develop with training, because at the onset of training DAT-KO and wild-type mice display similar biases towards sucrose and quinine. These data suggest that dopamine levels can modulate the updating of tastant values, a finding with implications for understanding sensory-specific motivation and reward seeking.


Assuntos
Aprendizagem por Discriminação/fisiologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/fisiologia , Dopamina/fisiologia , Preferências Alimentares/fisiologia , Motivação , Paladar/fisiologia , Animais , Aprendizagem por Associação/fisiologia , Comportamento de Escolha/fisiologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Paladar/genética
19.
J Comp Pathol ; 137(2-3): 130-2, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17645891

RESUMO

Sebaceous gland carcinoma is a common tumour in male gerbils but, to date, no information is available on its immunohistochemical properties. This report describes the histopathological and immunohistochemical features of such a tumour from a 4.5-year-old male gerbil. The tumour immunoreactivity profile was studied in respect of p53 protein, CEA, EMA, c-erbB-2, cytokeratin (CK) 14 and the CKs detected by AE1/AE3 antibodies (i.e. high molecular weight CKs 1, 2, 3, 4, 5, 6, 10, 14, 15 and 16, and low molecular weight CKs 7, 8 and 19). The differences observed in p53 and c-erbB-2 immunolabelling between carcinomatous and hyperplastic areas suggest that p53 mutations and amplification of c-erbB-2 may play a significant role in the oncogenesis of sebaceous gland carcinoma in the gerbil.


Assuntos
Gerbillinae , Receptor ErbB-2/metabolismo , Neoplasias das Glândulas Sebáceas/veterinária , Proteína Supressora de Tumor p53/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Antígeno Carcinoembrionário/metabolismo , Queratina-14/metabolismo , Masculino , Mutação/genética , Receptor ErbB-2/genética , Neoplasias das Glândulas Sebáceas/metabolismo , Proteína Supressora de Tumor p53/genética
20.
Int J Impot Res ; 29(4): 157-159, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28405028

RESUMO

Greater vibrotactile sensitivity has been related to better erectile function in men, and vibrotactile and pressure tactile sensitivity have been related to better sexual function in women. Our previous study found that, for both sexes, greater recalled body awareness during last sexual relation correlated with greater recalled desire and arousal. Using the same sample of that study (68 women and 48 men, recruited in the Lisbon area, Portugal), we tested if greater recalled body awareness during last sexual relation correlates with tactile pressure sensitivity, as assessed by von Frey microfilaments. In simple and partial correlations controlling for social desirability and smoking before last sex, the hypothesis was confirmed for women, but not for men. Greater tactile sensitivity might enhance sexual arousal through greater awareness of the body during sex, and/or more frequent and pleasant body sensations during sex might lead to greater tactile sensitivity in nonsexual situations. Pressure sensitivity might be more closely linked to sexual arousal in women than in men.


Assuntos
Conscientização/fisiologia , Coito/fisiologia , Dedos , Percepção do Tato/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pressão , Limiar Sensorial/fisiologia , Parceiros Sexuais , Adulto Jovem
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