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1.
Biol Lett ; 20(3): 20240010, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471564

RESUMO

Overkill of large mammals is recognized as a key driver of Pleistocene megafaunal extinctions in the Americas and Australia. While this phenomenon primarily affected mega-mammals, its impact on large Quaternary reptiles has been debated. Freshwater turtles, due to the scarcity of giant forms in the Quaternary record, have been largely neglected in such discussions. Here we present a new giant podocnemidid turtle, Peltocephalus maturin sp. nov., from the Late Pleistocene Rio Madeira Formation in the Brazilian Amazon, that challenges this assumption. Morphological and phylogenetic analyses of the holotype, a massive partial lower jaw, reveal close affinities to extant Amazonian species and suggest an omnivorous diet. Body size regressions indicate Pe. maturin possibly reached about 180 cm in carapace length and is among the largest freshwater turtles ever found. This finding presents the latest known occurrence of giant freshwater turtles, hinting at coexistence with early human inhabitants in the Amazon.


Assuntos
Tartarugas , Animais , Humanos , Filogenia , Brasil , Répteis , Água Doce , Mamíferos
2.
J Psycholinguist Res ; 53(4): 48, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758475

RESUMO

The main purpose of this study is to investigate the best approaches to teaching a foreign language to older people to help them achieve the desired results and explore their benefits. This review strictly follows the PRISMA methodology for systematic reviews and meta-analyses to identify the core experimental studies that deal with the topic of foreign language learning approaches among the older generations. Altogether eight studies detected were included in the systematic review. The available sources were found in Web of Science and Scopus. The findings indicate that foreign language learning can promote seniors' welfare and successful aging despite their learning outcomes, which means that the key benefit for third-age foreign language learners while learning a foreign language is not the achieved proficiency level, but the feeling of subjective satisfaction. This can be a good incentive to achieve better learning outcomes, provided that learners have been offered a pleasant and safe learning environment, using suitable learning approaches during which they can build on their acquired knowledge and experience, as well as discuss the topics they are interested in. Thus, foreign language teachers play an important part in seniors' educational process because their teaching methods and materials when adapted to the elderly's educational needs can have a positive impact on the maintenance and possibly, enhancement of the older people's cognitive functions and on the improvement of their mental activity, which consequently maintains their healthy aging.


Assuntos
Envelhecimento Saudável , Aprendizagem , Multilinguismo , Humanos , Aprendizagem/fisiologia , Envelhecimento Saudável/fisiologia , Idoso , Idioma
3.
Med Oral Patol Oral Cir Bucal ; 28(5): e433-e441, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37330965

RESUMO

BACKGROUND: The aim of the present study was to evaluate postoperative effects of platelet-rich fibrin (PRF) in wound and bone healing, pain, swelling and periodontal complications outcomes after impacted third molars extraction. MATERIAL AND METHODS: A prospective, randomized, split-mouth, double-blind clinical trial was conducted. PRF was placed within sockets following tooth removal and before suturing mucoperiosteal flap while no treatment was performed on control group's sockets. Patients were evaluated considering bone volume which was obtained in the 90-day postoperative period. Other variables included trabecular thickness, trabecular distance and grey values, pain, swelling, and wound healing. A Wilcoxon test and a t-Student test were used at a 5% significance level and a Friedman test was used to multiple comparisons. RESULTS: Forty-four surgeries were performed in the present study. The patients' mean age was 22.41 (± 2.75 years) and 72.73% were women. PRF was associated to increased trabecular thickness and bone volume means (p < 0.001). The experimental group had significantly lower pain scores at 4h, 6h, 8h, 16h, 24h, and 72h (p ˂ 0.05). Mean swelling was lower on the experimental group (p < 0.001). The PRF group showed significant higher wound healing (p ˂ 0.001). CONCLUSIONS: Alveolar filling with PRF improves wound and bone healing after extractions while also decreasing pain and swelling in the postoperative period.


Assuntos
Fibrina Rica em Plaquetas , Dente Impactado , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Dente Serotino/cirurgia , Estudos Prospectivos , Extração Dentária/efeitos adversos , Dente Impactado/cirurgia , Dor/etiologia
4.
Parasitol Res ; 121(7): 2141-2156, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35610523

RESUMO

Chagas disease (CD) is a neglected disease, prevalent and endemic in Latin America, but also present in Europe and North America. The main treatment used for this disease is benznidazole, but its efficacy is variable in the chronic phase and presents high toxicity. So, there is a need for the development of new therapeutic agents. The five-membered heterocyclic 1,2,4-oxadiazole ring has received attention for its unique properties and a broad spectrum of biological activities and is therefore a potential candidate for the development of new drugs. Thus, the aim of this study was to evaluate the activity of the N-cyclohexyl-3-(3-methylphenyl)-1,2,4-oxadiazol-5-amine (2) on the evolutionary forms of Trypanosoma cruzi strain Y, as well as its mechanisms of action and in silico theoretical approach. The results by computational method showed an interaction of the 1,2,4-oxadiazole (2) with TcGAPDH, cruzain, and trypanothione reductase, showing good charge distribution and affinity in those three targets. Furthermore, cytotoxicity in LLC-MK2 cells was performed by the MTT method. In the assays with different parasite forms, the tested compound showed similar time-dependent concentration effect. The evaluation of the antiamastigote effect between the two concentrations tested showed a reduction in the number of infected cells and also in the number of amastigotes per infected cell. By flow cytometry, the compound (2) displayed alterations suggestive of necrotic events. Finally, in scanning electron microscopy structural alterations were present, characteristic of necrosisin the epimastigote forms. Overall, the 1,2,4-oxadiazole derivative (2) here evaluated opens perspectives to the development of new antichagasic agents.


Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Humanos , Oxidiazóis/farmacologia , Oxidiazóis/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
5.
J Intellect Disabil Res ; 66(12): 1000-1008, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35734961

RESUMO

BACKGROUND: Low muscle quality index (MQI) is a potential risk of developing functional impairments in older people. However, considering that individuals with Down syndrome (DS) present with a faster decline in biological aging, an investigation on MQI in individuals with DS is necessary. The aims of this present cross-sectional study were to compare (1) MQI between adolescents with and without DS and (2) evaluate laboratory versus field-based estimates of MQI. METHODS: Fifty-six adolescents were recruited and separated into two groups: DS (n = 30, 13 boys and 17 girls; age: 12.38 ± 3.07 years) and a control (non-DS; n = 26, 9 boys and 17 girls; age: 12.46 ± 2.88 years). Laboratory MQI was derived from the ratio of grip strength to arm muscle mass (in kg) measured by dual-energy X-ray absorptiometry (DXA). Field-based MQI was quantified from the ratio of hand grip strength (HGS) to body mass index (BMI). For statistical analyses, a two-way ANOVA was conducted for group comparisons, and a Pearson correlation was used to test the association between field MQI and laboratory MQI. RESULTS: Adolescents with DS displayed lower field (P = 0.001), laboratory MQI estimates (P = 0.001) and HGS (P = 0.001) as compared non-DS. Also, there was a strong correlation effect between field MQI and laboratory MQI estimates (P < 0.001, R = 0.81). CONCLUSION: Adolescents with DS have lower field and laboratory MQI compared with adolescents without DS. Simpler field MQI might be used in daily clinical practice, with special attention to those with DS.


Assuntos
Síndrome de Down , Força da Mão , Masculino , Feminino , Humanos , Adolescente , Idoso , Criança , Força da Mão/fisiologia , Estudos Transversais , Absorciometria de Fóton , Índice de Massa Corporal , Músculos , Composição Corporal/fisiologia , Força Muscular/fisiologia
6.
J Toxicol Pathol ; 35(2): 159-170, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35516837

RESUMO

Exposure of Sprague-Dawley (SD) rats to acrylamide (AA) or di-butyl-phthalate (DBP) from the 12th gestational day to the 16th postnatal week (PNW) has been shown to reduce the effectiveness of orchiopexy in recovering the testicular alterations associated with experimental cryptorchidism established at weaning. Herein, we provide information about the long-term effects of AA or DBP on the testes of cryptorchid/orchiopexic rats. Male offspring exposed in utero to 10 mg/kg/day AA or 500 mg/kg/day DBP underwent bilateral surgical cryptorchidism at the 3rd PNW and orchiopexy at the 6th week, with continuous exposure to the chemicals through diet until the 58th week. Regardless of the test chemical, there were severe qualitative/quantitative alterations in the seminiferous tubules and increased numbers of Leydig cells. There was an increase and decrease in the number of tubules with c-Kit- and placental alkaline phosphatase-labeled germ cells, respectively, as compared to those in the control group, suggesting an imbalance between apoptosis and cell proliferation processes. The histological scores of the testicular lesions at the end of this one-year study were higher than those in the previous 16-week study, indicating that exposure of rats to the toxicants AA or DBP enhanced the testicular alterations induced by the chemicals beginning at the intra-uterine life, and impaired the effectiveness of orchiopexy in restoring the testes to normal morphology. Although the present experimental protocol does not completely replicate the natural human undescended testes, our findings may contribute to understanding the alterations occurring in cryptorchid/orchiopexic testes potentially exposed to exogenous chemicals for extended periods.

7.
Int J Exp Pathol ; 102(1): 57-69, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33502821

RESUMO

Cryptorchidism is one of the main risk factors for infertility and testicular cancer. Orchiopexy surgery corrects cryptorchidism effects. Different models of cryptorchidism developed in the rat include surgery. We assessed testicular alterations in rats submitted to surgical cryptorchidism and examined their potential for reversibility at different time points in order to verify time dependency effect(s) on the recovery of the undescended testes. Cryptorchidism was induced in 3-week-old rats. Animals were euthanized 3, 6 or 11 weeks after surgery to evaluate the morphological progression of cryptorchidism-induced germinative epithelial alterations. Other groups underwent orchiopexy 3, 5 or 9 weeks after surgical cryptorchidism, before or after puberty. Animals were euthanized 3 or 8 weeks after orchiopexy. Controls underwent sham surgery at the same time points as the surgical groups. Cryptorchid testes showed decreased weight, germinative epithelial degeneration, apoptosis and vacuolation, corresponding to impairment of spermatogenesis and of Sertoli cells. Some tubules has a Sertoli cell-only pattern and atrophy. The intensity of damage was related to the duration of cryptorchidism. After orchiopexy, spermatogenesis completely recovered only when testicular relocation occurred before puberty and the interval for recovery was extended. These results indicate that age, sexual maturity and extension of germ cell damage were relevant for producing germ cell restoration and normal spermatogenesis. We provide original observations on the time dependency of testicular alterations induced by cryptorchidism and their restoration using morphologic, morphometric and immunohistochemical approaches. It may be useful to study germ cell impairment, progression and recovery in different experimental settings, including exposure to exogenous chemicals.


Assuntos
Criptorquidismo/patologia , Criptorquidismo/cirurgia , Orquidopexia/métodos , Testículo/patologia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Espermatogênese/fisiologia , Fatores de Tempo
8.
Int J Legal Med ; 135(2): 639-648, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32840664

RESUMO

The present study correlated the mineralization of third molars to chronological age using a modified classification based on Demirjian's stages in a Brazilian subpopulation and compared with the original classification. A total of 1082 patients with age ranging from 6 to 26 years were included in the sample, with at least one third molar on panoramic radiographs. The third molars were classified according to the original Demirjian classification (8 stages) and a new model based on the Demirjian method, where the original stages were grouped into four stages: AB-enamel mineralization; CD-crown dentin mineralization; EFG-root formation; and H-complete development. Statistical analyses were performed by Kruskal-Wallis/Dunn tests (α = 0.05) and the multinomial logistic regression model. Data were analyzed according to percentiles for the probability of an individual being over 18 years old. The mean ages of the stages in both classifications did not present a significant difference between superior and inferior arches (p < 0.05). The differences in mean ages between all the stages of mineralization were statistically significant (p < 0.001) only for the 4-stage classification. Males attained root formation and complete formation earlier than females (p < 0.05) in the 4-stage classification. The modified classification system showed dependence between chronological age and mineralization stages of third molars, simplifying the age estimation process. At stage H, females present a 95.7% chance of being over 18, while for males, this probability is 89.6%. This modified classification system simplifies the dental age estimation process based on third molars and can be used as a reference for future studies.


Assuntos
Determinação da Idade pelos Dentes/métodos , Dente Serotino/crescimento & desenvolvimento , Calcificação de Dente , Adolescente , Adulto , Brasil/epidemiologia , Criança , Fenômenos Fisiológicos Dentários , Feminino , Humanos , Masculino , Radiografia Panorâmica , Adulto Jovem
9.
Br Poult Sci ; 62(2): 188-192, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33026245

RESUMO

1. The aim of this study was to compare the resistance pattern of thermophilic Campylobacter spp. isolated from conventional production (n = 34) and backyard poultry flocks (n = 36) from Rio de Janeiro State, Brazil. The disc diffusion method and statistical tests were used for investigation and analysis of the resistance pattern of Campylobacter spp. isolated from different rearing systems.2. Antimicrobial resistance percentages to amoxycillin with clavulanic acid (AMC), ampicillin (AMP), ceftiofur (CTF), ciprofloxacin (CIP), enrofloxacin (ENO), erythromycin (ERI), gentamicin (GEN) and tetracycline (TET) were 32.4%, 44.1%, 67.6%, 97.1%, 82.4%, 26.5%, 5.9% and 38.2% in conventional production flocks respectively, while the backyard flock's resistance levels were 0.0%, 13.9%, 69.4%, 100.0%, 91.7%, 5.6%, 0.0% and 16.7%, respectively.3. Campylobacter spp. from conventional poultry production was more resistant to AMC, AMO, ERI and TET (P > 0.05) when compared to strains from backyard poultry. A higher frequency of resistance to fluoroquinolones (FLQ), CIP and ENO, was observed in strains from both systems, demonstrating the spread of resistant strains among poultry production environments.


Assuntos
Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Animais , Antibacterianos/farmacologia , Brasil , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Galinhas , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana/veterinária , Aves Domésticas
10.
Water Sci Technol ; 83(11): 2793-2808, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34115632

RESUMO

In this work, mixed oxides of LaxCa1-xMnO3 perovskite type (x = 0, 0.5 and 1.0) were synthesized through modified proteic method using collagen and calcination process at 700 °C/2 h in order to remove the commercial textile dye Bezaktiv Blue S-MAX from water. Oxides were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2 physisorption, scanning electron microscopy (SEM) and point of zero charge (PZC) techniques while the dye only by the first two techniques. The XRD showed that perovskite monophase was obtained for x = 0.5 and 1.0. However, for x = 0, the low crystalline perovskite phase was obtained in the midst of precursor oxides. FTIR showed the adsorption process did not damage the adsorbents structure. The successful obtained materials have meso and macroporous with slit or cavity shape, rough surface and particles with varying sizes. The pseudo-second-order model was the one that best fit the kinetic data. The process must occur through electrostatic surface interactions between the adsorbent surface and the dye molecule. For the equilibrium study, Langmuir isotherm is the most suitable when using LaMnO3 adsorbent, while Freundlich isotherm was better suited when used the other two materials. The adsorbents were termally regenerated and reused five times. The best performance was exhibited by LaMnO3.


Assuntos
Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Poluentes Químicos da Água/análise
11.
Int Endod J ; 53(9): 1299-1306, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535964

RESUMO

AIM: To assess the influence of artefacts generated by metal posts on the detection of simulated internal root resorption (IRR) in adjacent teeth using cone-beam computed tomography (CBCT) and to verify the impact of metal artefact reduction (MAR) on these cases. METHODOLOGY: CBCT images of 14 premolar teeth were acquired before and after IRR simulation using chemical and mechanical procedures, in an OP300 Maxio unit, with and without MAR. Each tooth was placed in the socket of a human mandible and scanned under three different conditions: (i) without adjacent teeth - control group; (ii) distal adjacent tooth restored with metal post; and (iii) with both adjacent teeth restored with metal post. Five oral radiologists scored the IRR detection using a 5-point scale. Diagnostic values were obtained for the tested groups and compared using two-way analysis of variance (α = 0.05). RESULTS: The presence of a single adjacent tooth restored with metal post did not significantly influence the diagnostic values for IRR detection (P > 0.05). The presence of both adjacent teeth with metal posts, without MAR application, was associated with a significantly lower area under the ROC curve (Az) compared to the control (P = 0.0182). In this case, the application of MAR increased Az, leading to nonsignificant differences from the control group and the group with one adjacent restored tooth (P > 0.05). Sensitivity decreased significantly when two adjacent restored teeth were present, regardless of MAR application (P = 0.0379). Specificity was not affected by the conditions tested (P > 0.05). CONCLUSION: CBCT detection of IRR was impaired by artefacts only when both adjacent teeth restored with metal posts were present. In such cases, activation of MAR improved the performance on this diagnostic task.


Assuntos
Reabsorção da Raiz , Tomografia Computadorizada de Feixe Cônico Espiral , Fraturas dos Dentes , Tomografia Computadorizada de Feixe Cônico , Humanos , Metais , Raiz Dentária
13.
Int Endod J ; 52(6): 866-873, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30585641

RESUMO

AIM: To assess the influence of artefacts, the metal artefact reduction (MAR) tool and kilovoltage (kVp) on the diagnosis of simulated external root resorption (ERR) in teeth close and distant to zirconium implants in cone beam computed tomography (CBCT) images. METHODOLOGY: Cavities (0.62 mm in diameter and 0.19 mm deep) were created in the apical thirds of 12 roots on the buccal, lingual, distal or mesial surface; ten roots served as controls. The roots were randomly positioned in the first and second right and left premolar sockets of a dry human mandible, and a zirconium implant was placed in the socket of the first right molar. A ProMax 3D unit varying kVp (70, 80, or 90 kVp) and with the MAR tool activated or not was used to obtain CBCT scans. Five examiners evaluated all images to determine the area under the receiver operating characteristic (ROC) curve, sensitivity and specificity. RESULTS: The ROC values and sensitivity were not affected by MAR or artefacts regardless of the distance to the implant (P > 0.05), whilst increasing kVp from 70 to 90 led to a significant increase in these values (P = 0.0202 and 0.0199, respectively). Specificity was not affected by the factors studied (P > 0.05). CONCLUSIONS: Amongst the factors studied, only kVp influenced the diagnosis of simulated external root resorption in CBCT images. Increasing kVp from 70 to 90 improved the accuracy in diagnosing the simulated lesions.


Assuntos
Reabsorção da Raiz , Artefatos , Tomografia Computadorizada de Feixe Cônico , Humanos , Mandíbula , Raiz Dentária , Zircônio
14.
Int Endod J ; 52(10): 1410-1416, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31111507

RESUMO

AIM: To evaluate the association between endodontic technical errors and the root canal configuration (RCC) of human premolars, as well as their relationship with periapical lesions through cone-beam computed tomography (CBCT) images. METHODOLOGY: The sample consisted of CBCT scans belonging to 136 patients, totalling 152 root filled premolars (185 roots). CBCT images were evaluated by two oral radiologists. RCC was recorded according to Vertucci's classification, and the endodontic treatment quality was judged on the presence and type of technical endodontic errors (underfilling, overfilling, nonhomogeneous filling, nonfilled canal, fractured instruments, root deviation and absence of coronal restoration). In addition, the presence of periapical lesions associated with each RCC was recorded. Data were expressed by frequencies and percentages, and intraobserver agreement was calculated using the Kappa test. RESULTS: The most common RCC was type I (71%), followed by type IV (15%), type II (8%), type V (3%), type VI (1%) and type III (1%). Types VII and VIII were not observed in the sample. Underfilling was the most frequent endodontic technical error for most RCCs, except for types IV, V and 'other', whose most frequent error was a nonfilled canal. The presence of technical errors was greater with an increase in the proportion of the periapical lesions. The intraobserver agreement was excellent. CONCLUSIONS: There was an increase in the prevalence of endodontic technical errors and in the presence of periapical lesions as the anatomical complexity of the root canals increased. Underfilled and nonfilled canal were the most frequent endodontic technical errors.


Assuntos
Cavidade Pulpar , Tomografia Computadorizada de Feixe Cônico Espiral , Dente Pré-Molar , Tomografia Computadorizada de Feixe Cônico , Humanos , Tratamento do Canal Radicular
15.
Occup Med (Lond) ; 69(8-9): 598-603, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31960054

RESUMO

BACKGROUND: Studies into the mental health of firefighters have primarily focussed on individual factors (e.g. biological and psychological factors). Little is known about how exposure to traumatic events and psychosocial and organizational work factors influence firefighters' mental health despite the evidence that these are important for employee health. AIMS: To study job demands, job control, social support and operational trauma as predictors of firefighters' psychiatric morbidity, and whether job control and social support moderate these relationships. METHODS: Participants were drawn from a longitudinal cohort study of firefighters in Brazil. Portuguese-language variants of the Self-Report Questionnaire (SRQ-20) and Traumatic Events List for Emergency Professionals measured psychiatric morbidity and exposure to traumatic events. Job demands, job control and social support were measured by the Job Stress Scale. Hierarchical regressions were run controlling for socio-demographics and previous psychiatric morbidity. Subsequent regression steps first included the proposed predictors followed by their interactions. RESULTS: Thirteen per cent of the sample (n = 40/312) met the caseness criteria indicating psychiatric morbidity. Operational trauma, job demands, job control and social support predicted psychiatric morbidity. Both job control and social support functioned as moderators and where these moderators were high, the job demands and psychiatric morbidity relationships were weaker. CONCLUSIONS: These findings show that psychosocial factors and operational trauma predict firefighters' psychiatric morbidity. Crucially, the results that improving social support and job control could mitigate the detrimental influence of job demands highlight the need for more research and practice towards organizational-level interventions.


Assuntos
Bombeiros/psicologia , Transtornos Mentais/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Brasil/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Doenças Profissionais/psicologia , Estresse Ocupacional/epidemiologia , Cultura Organizacional , Apoio Social , Inquéritos e Questionários , Carga de Trabalho
16.
Toxicol Mech Methods ; 29(7): 488-498, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31050326

RESUMO

The increased incidence of testicular disorders in young men and the possible influence of environmental chemicals, such as dibutyl phthalate (DBP) and acrylamide (AA), requires experimental models for identifying modes of action. Most published reproductive toxicologic studies use RNA samples from the total testis to evaluate testicular gene expression; however, analyses of isolated cell types could provide a more specific tool. Among testicular germ cells, spermatogonia are critical since they represent the onset of spermatogenesis. This study aimed, (1) to establish a technique for spermatogonia isolation; (2) to apply this isolation technique to verify possible gene expression alterations (Pou5f1, Kitlg, Mki-67, Bak1 and Spry4) in prepubertal post-natal day, (PND24) and pubertal (PND45) testes after in utero and postnatal exposure to DBP or AA. The technique was efficient for isolation of a majority of spermatogonia. In utero DBP exposure led to reduced litter body weight at birth, reduced anogenital distance of male pups on PND4, and increased frequency of male nipple retention on PND14 compared to controls. DBP-exposed relative testes weights were reduced only at PND24 compared to control but they did not differ at PND45. DBP-exposed animals showed reduced expression levels of Pou5f1 and Mki67 on PND24, and reduced expression of Pou5f1 and Spry4 on PND45. AA exposure reduced expression of Pou5f1, Mki67, and Spry4 at PND45 although not significantly. Our results suggest that DBP acts by reducing cell proliferation and impairing differentiation in prepubertal and pubertal testes.


Assuntos
Acrilamida/toxicidade , Dibutilftalato/toxicidade , Poluentes Ambientais/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Espermatogônias/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Peso Corporal , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos Sprague-Dawley , Espermatogônias/patologia , Testículo/embriologia , Testículo/crescimento & desenvolvimento , Testículo/patologia
17.
Hepatology ; 65(6): 2045-2058, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28195332

RESUMO

Sarcopenia or skeletal muscle loss is a frequent, potentially reversible complication in cirrhosis that adversely affects clinical outcomes. Hyperammonemia is a consistent abnormality in cirrhosis that results in impaired skeletal muscle protein synthesis and breakdown (proteostasis). Despite the availability of effective ammonia-lowering therapies, whether lowering ammonia restores proteostasis and increases muscle mass is unknown. Myotube diameter, protein synthesis, and molecular responses in C2C12 murine myotubes to withdrawal of ammonium acetate following 24-hour exposure to 10 mM ammonium acetate were complemented by in vivo studies in the hyperammonemic portacaval anastomosis rat and sham-operated, pair-fed Sprague-Dawley rats treated with ammonia-lowering therapy by l-ornithine l-aspartate and rifaximin orally for 4 weeks. We observed reduced myotube diameter, impaired protein synthesis, and increased autophagy flux in response to hyperammonemia, which were partially reversed following 24-hour and 48-hour withdrawal of ammonium acetate. Consistently, 4 weeks of ammonia-lowering therapy resulted in significant lowering of blood and skeletal muscle ammonia, increase in lean body mass, improved grip strength, higher skeletal muscle mass and diameter, and an increase in type 2 fibers in treated compared to untreated portacaval anastomosis rats. The increased skeletal muscle myostatin expression, reduced mammalian target of rapamycin complex 1 function, and hyperammonemic stress response including autophagy markers normally found in portacaval anastomosis rats were reversed by treatment with ammonia-lowering therapy. Despite significant improvement, molecular and functional readouts were not completely reversed by ammonia-lowering measures. CONCLUSION: Ammonia-lowering therapy results in improvement in skeletal muscle phenotype and function and molecular perturbations of hyperammonemia; these preclinical studies complement previous studies on ammonia-induced skeletal muscle loss and lay the foundation for prolonged ammonia-lowering therapy to reverse sarcopenia of cirrhosis. (Hepatology 2017;65:2045-2058).


Assuntos
Hiperamonemia/complicações , Cirrose Hepática/complicações , Proteínas Musculares/efeitos dos fármacos , Rifamicinas/farmacologia , Sarcopenia/tratamento farmacológico , Amônia/sangue , Análise de Variância , Animais , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças , Homeostase/fisiologia , Injeções Intraperitoneais , Cirrose Hepática/patologia , Masculino , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Rifaximina , Sarcopenia/etiologia , Sarcopenia/patologia
18.
Ophthalmology ; 125(3): 352-360, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29103791

RESUMO

PURPOSE: To develop a visual field (VF) feature model to predict the reversal of glaucoma hemifield test (GHT) results to within normal limits (WNL) after 2 consecutive outside normal limits (ONL) results. DESIGN: Retrospective cohort study. PARTICIPANTS: Visual fields of 44 503 eyes from 26 130 participants. METHODS: Eyes with 3 or more consecutive reliable VFs measured with the Humphrey Field Analyzer (Swedish interactive threshold algorithm standard 24-2) were included. Eyes with ONL GHT results for the 2 baseline VFs were selected. We extracted 3 categories of VF features from the baseline tests: (1) VF global indices (mean deviation [MD] and pattern standard deviation), (2) mismatch between baseline VFs, and (3) VF loss patterns (archetypes). Logistic regression was applied to predict the GHT results reversal. Cross-validation was applied to evaluate the model on testing data by the area under the receiver operating characteristic curve (AUC). We ascertained clinical glaucoma status on a patient subset (n = 97) to determine the usefulness of our model. MAIN OUTCOME MEASURES: Predictive models for GHT results reversal using VF features. RESULTS: For the 16 604 eyes with 2 initial ONL results, the prevalence of a subsequent WNL result increased from 0.1% for MD < -12 dB to 13.8% for MD ≥-3 dB. Compared with models with VF global indices, the AUC of predictive models increased from 0.669 (MD ≥-3 dB) and 0.697 (-6 dB ≤ MD < -3 dB) to 0.770 and 0.820, respectively, by adding VF mismatch features and computationally derived VF archetypes (P < 0.001 for both). The GHT results reversal was associated with a large mismatch between baseline VFs. Moreover, the GHT results reversal was associated more with VF archetypes of nonglaucomatous loss, severe widespread loss, and lens rim artifacts. For a subset of 97 eyes, using our model to predict absence of glaucoma based on clinical evidence after 2 ONL results yielded significantly better prediction accuracy (87.7%; P < 0.001) than predicting GHT results reversal (68.8%) with a prescribed specificity 67.7%. CONCLUSIONS: Using VF features may predict the GHT results reversal to WNL after 2 consecutive ONL results.


Assuntos
Glaucoma/diagnóstico , Pressão Intraocular , Recuperação de Função Fisiológica/fisiologia , Testes de Campo Visual/métodos , Campos Visuais/fisiologia , Idoso , Seguimentos , Glaucoma/fisiopatologia , Humanos , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Fatores de Tempo
19.
Epidemiol Infect ; 146(10): 1293-1300, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29925445

RESUMO

Reducing the risk of human immunodeficiency virus type 1 (HIV-1) transmission is still a public health priority. The development of effective control strategies relies on the quantification of the effects of prophylactic and therapeutic measures in disease incidence. Although several assays can be used to estimate HIV incidence, these estimates are limited by the poor performance of these assays in distinguishing recent from long-standing infections. To address such limitation, we have developed an assay to titrate p24-specific IgG3 antibodies as a marker of recent infection. The assay is based on a recombinant p24 protein capable to detect total IgG antibodies in sera using a liquid micro array and enzyme-linked immunosorbent assay. Subsequently, the assay was optimised to detect and titrate anti-p24 IgG3 responses in a panel of sequential specimens from seroconverters over 24 months. The kinetics of p24-specific IgG3 titres revealed a transient peak in the 4 to 5-month period after seroconversion. It was followed by a sharp decline, allowing infections with less than 6 months to be distinguished from older ones. The developed assay exhibited a mean duration of recent infection of 144 days and a false-recent rate of ca. 14%. Our findings show that HIV-1 p24-specific IgG3 titres can be used as a tool to evaluate HIV incidence in serosurveys and to monitor the efficacy of vaccines and other transmission control strategies.


Assuntos
Anticorpos Antivirais/sangue , Proteína do Núcleo p24 do HIV/imunologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV-1/imunologia , Imunoglobulina G/sangue , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , Incidência , Cinética , Soroconversão , Estudos Soroepidemiológicos , Fatores de Tempo
20.
Eur Phys J E Soft Matter ; 41(11): 136, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30467606

RESUMO

We introduce a density-functional formalism based on the Parsons-Lee and the generalized van der Waals theories in order to describe the thermodynamics of anisotropic particle systems with steric interactions. For ellipsoids of revolution, the orientational distribution function is obtained by minimizing the free energy functional and the equations of state are determined. The system exhibits a nematic-isotropic discontinuous transition, characterized by a phase separation between nematic and isotropic phases at finite as well low packing fractions. The model presents a phase behavior which is in good agreement with Monte Carlo simulations for finite aspect ratios.

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