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1.
Trop Anim Health Prod ; 55(3): 189, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37138172

RESUMO

This study aimed to determine the effect of growth rates on the hormonal status and puberty onset. Forty-eight Nellore heifers were weaned at 3.0 ± 0.1 (means ± standard error of the mean) months old were blocked according to body weight at weaning (84 ± 2 kg) and randomly assigned to treatments. The treatments were arranged in 2 × 2 factorial according to the feeding program. The first program was high (H; 0.79 kg/day) or control (C; 0.45 kg/day) average daily gain (ADG) from 3rd to 7th month of age (growing phase I). The second program was also high (H; 0.70 kg/day) or control (C; 0.50 kg/day) ADG from the 7th month until puberty (growing phase II), resulting in four treatments: HH (n = 13), HC (n = 10), CH (n = 13), and CC (n = 12). To achieve desired gains, heifers in high ADG program were fed ad libitum dry matter intake (DMI), and the control group was offered around 50% of ad libitum DMI of high group. All heifers received a diet with similar composition. Puberty was assessed weekly by ultrasound examination, and the largest follicle diameter was evaluated every month. Blood samples were collected to quantify leptin, insulin growth factor-1 (IGF1) and luteinizing hormone (LH). At 7 months of age, heifers in high ADG were 35 kg heavier than the control. Heifers in the HH had greater DMI compared with CH in phase II. The puberty rate at 19 months old was greater in the HH treatment (84%) than in the CC (23%), but there was no difference between HC (60%) and CH (50%) treatments. Heifers from HH treatment had greater serum leptin concentration than others at 13 months old, and serum leptin was greater in HH compared with CH and CC at 18 months old. High heifers in phase I had greater serum IGF1 concentration than the control. In addition, HH heifers had a greater diameter of the largest follicle than CC. There was no interaction between phases and age in any variable relative to the LH profile. However, the heifers' age was the main factor that increased the frequency of LH pulse. In conclusion, increasing ADG was associated with greater ADG, serum leptin and IGF-1 concentration, and puberty onset; however, LH concentration was affected mainly by age of the animal. The increasing growth rate at younger age made heifers more efficient.


Assuntos
Leptina , Maturidade Sexual , Feminino , Bovinos , Animais , Desmame , Dieta/veterinária , Insulina , Ração Animal/análise
2.
Nature ; 519(7543): 344-8, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25788097

RESUMO

Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.


Assuntos
Dióxido de Carbono/análise , Sequestro de Carbono , Floresta Úmida , Atmosfera/química , Biomassa , Brasil , Carbono/análise , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Caules de Planta/metabolismo , Árvores/crescimento & desenvolvimento , Árvores/metabolismo , Clima Tropical , Madeira/análise
3.
Regul Toxicol Pharmacol ; 125: 105026, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34389358

RESUMO

Next generation risk assessment (NGRA) is an exposure-led, hypothesis-driven approach that has the potential to support animal-free safety decision-making. However, significant effort is needed to develop and test the in vitro and in silico (computational) approaches that underpin NGRA to enable confident application in a regulatory context. A workshop was held in Montreal in 2019 to discuss where effort needs to be focussed and to agree on the steps needed to ensure safety decisions made on cosmetic ingredients are robust and protective. Workshop participants explored whether NGRA for cosmetic ingredients can be protective of human health, and reviewed examples of NGRA for cosmetic ingredients. From the limited examples available, it is clear that NGRA is still in its infancy, and further case studies are needed to determine whether safety decisions are sufficiently protective and not overly conservative. Seven areas were identified to help progress application of NGRA, including further investments in case studies that elaborate on scenarios frequently encountered by industry and regulators, including those where a 'high risk' conclusion would be expected. These will provide confidence that the tools and approaches can reliably discern differing levels of risk. Furthermore, frameworks to guide performance and reporting should be developed.


Assuntos
Alternativas aos Testes com Animais/métodos , Qualidade de Produtos para o Consumidor/normas , Cosméticos/normas , Medição de Risco
4.
Nitric Oxide ; 93: 53-70, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541734

RESUMO

In this year there is the 40th anniversary of the first publication of plant nitric oxide (NO) emission by Lowell Klepper. In the decades since then numerous milestone discoveries have revealed that NO is a multifunctional molecule in plant cells regulating both plant development and stress responses. Apropos of the anniversary, these authors aim to review and discuss the developments of past concepts in plant NO research related to NO metabolism, NO signaling, NO's action in plant growth and in stress responses and NO's interactions with other reactive compounds. Despite the long-lasting research efforts and the accumulating experimental evidences numerous questions are still needed to be answered, thus future challenges and research directions have also been drawn up.


Assuntos
Óxido Nítrico/metabolismo , Fenômenos Fisiológicos Vegetais , Plantas/metabolismo , Nitrato Redutase/fisiologia , Óxido Nítrico Sintase/fisiologia , Estresse Nitrosativo/fisiologia , Desenvolvimento Vegetal , Reprodução/fisiologia , Transdução de Sinais/fisiologia , Simbiose/fisiologia
5.
Arch Toxicol ; 92(2): 611-617, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29127450

RESUMO

Skin sensitisation is the regulatory endpoint that has been at the centre of concerted efforts to replace animal testing in recent years, as demonstrated by the Organisation for Economic Co-operation and Development (OECD) adoption of five non-animal methods addressing mechanisms under the first three key events of the skin sensitisation adverse outcome pathway. Nevertheless, the currently adopted methods, when used in isolation, are not sufficient to fulfil regulatory requirements on the skin sensitisation potential and potency of chemicals comparable to that provided by the regulatory animal tests. For this reason, a number of defined approaches integrating data from these methods with other relevant information have been proposed and documented by the OECD. With the aim to further enhance regulatory consideration and adoption of defined approaches, the European Union Reference Laboratory for Alternatives to Animal testing in collaboration with the International Cooperation on Alternative Test Methods hosted, on 4-5 October 2016, a workshop on the international regulatory applicability and acceptance of alternative non-animal approaches, i.e., defined approaches, to skin sensitisation assessment of chemicals used in a variety of sectors. The workshop convened representatives from more than 20 regulatory authorities from the European Union, United States, Canada, Japan, South Korea, Brazil and China. There was a general consensus among the workshop participants that to maximise global regulatory acceptance of data generated with defined approaches, international harmonisation and standardisation are needed. Potential assessment criteria were defined for a systematic evaluation of existing defined approaches that would facilitate their translation into international standards, e.g., into a performance-based Test Guideline. Informed by the discussions at the workshop, the ICATM members propose practical ways to further promote the regulatory use and facilitate adoption of defined approaches for skin sensitisation assessments.


Assuntos
Alternativas aos Testes com Animais/normas , Testes Cutâneos/normas , Testes de Toxicidade/normas , Cooperação Internacional , Padrões de Referência
6.
Photochem Photobiol Sci ; 16(12): 1771-1777, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29087429

RESUMO

In photobiocatalytical processes involving the simultaneous oxidation of water and reduction of specific organic molecules (e.g., cofactors), the lack of physical separation of the redox half-reactions adversely affects the product stability. This is largely because organic molecules are generally less stable within harsh oxidative environments. In general, surface co-catalysts are able to improve the selectivity of photocatalysts towards water oxidation. However, harsh oxidative environments reduce the chemical stability of the organic molecules. Herein, we show that the use of Co3O4 as a surface co-catalyst on silver orthophosphate improve water photo-oxidation in the presence of organic dye molecules, such as methylene blue, that typically exhibits susceptibility toward photodegradation. The presence of Co3O4 on the photocatalyst surface prevents the adsorption of the organic dye, thus reducing its degradation rate. These findings provide a promising scenario for the visible light-driven reduction of organic molecules using water as an electron donor.

7.
Eur J Gynaecol Oncol ; 37(5): 722-725, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29787019

RESUMO

OBJECTIVES: To report a case of apocrine adenocarcinoma of the vulva and introduce the sentinel node dissection as a method to diagnose it. MATERIALS AND METHODS: Description of a case of a 77-year-old woman with histological diagnostic of apocrine adenocarcinoma of the vulva and literature review of the 16 cases published from 1954 to nowadays. RESULTS: Treatment of vulvar apocrine carcinoma is controversial given its low incidence and the small number of cases which have been reported. CONCLUSION: Selective sentinel lymph node biopsy may provide a valid option in selected patients to decrease their clinical complications.


Assuntos
Adenocarcinoma/patologia , Neoplasias Vulvares/patologia , Adenocarcinoma/cirurgia , Idoso , Feminino , Humanos , Biópsia de Linfonodo Sentinela , Neoplasias Vulvares/cirurgia
8.
Int J Immunogenet ; 40(1): 54-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23136897

RESUMO

The concept that HLA antibodies are specific for epitopes rather than HLA antigens is important not only for the determination of mismatch acceptability for sensitized patients but also for a better understanding of the antibody response to an HLA mismatch. Numerous publications describe epitope-specific antibodies, but there is no standardized information about the repertoire of clinically relevant HLA epitopes. Under auspices of the 16th IHIW, we have developed a website-based registry of antibody-verified HLA epitopes. Epitope notations are based on HLA molecular modelling of amino acid residues in polymorphic sequence positions. Informative epitope-specific antibodies had been induced by a transplant, transfusion or pregnancy and were monoclonal antibodies or eluates of sera absorbed with single HLA alleles. Antibody reactivity was determined in binding assays with single-allele panels. Antibody producer/immunizer HLA types enhanced the characterization of specific epitopes. The Registry also includes epitopes described in original research publications. Based on the extent of antibody reactivity information, we assigned epitope status as confirmed (well documented) or provisional (more data are needed). At present, the Registry has 69 HLA-ABC, 53 DRB1/3/4/5, 17 DQ, 8 DP and 22 MICA antibody-verified epitopes and will be updated on a quarterly basis. Laboratories worldwide continue to submit data about previously unreported antibody-specific epitopes. For each epitope, the website shows its amino acid composition and HLA alleles that share the epitope. Links show antibody reactivity patterns, sensitization information and references. Other links show molecular modelling of corresponding structural epitopes and polymorphic residue information for epitope-carrying alleles. The website will also have a link to epitope frequency information in different populations. Search functions will list mismatched epitopes on mismatched alleles for selected HLA types. The HLA Epitope Registry will become a valuable resource for researchers interested in HLA compatibility at the epitope level and investigating antibody responses to HLA mismatches.


Assuntos
Anticorpos , Epitopos , Antígenos HLA , Internet , Algoritmos , Alelos , Sequência de Aminoácidos , Anticorpos/genética , Anticorpos/imunologia , Especificidade de Anticorpos , Epitopos/genética , Epitopos/imunologia , Feminino , Antígenos HLA/genética , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Isoanticorpos/genética , Isoanticorpos/imunologia , Gravidez
9.
J Arthroplasty ; 28(7): 1057-60, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23523484

RESUMO

This study offers a descriptive analysis of the economic costs of Periprosthetic joint infection (PJI) of the knee for the public health system of Andalusia (Spain) The data are based on consecutive patients with PJI treated in our Bone and Joint Infection Unit between January 2005 and January 2010. The total cost for all patients with knee PJI was 4,151,843 $ (3,202,841 €), i.e., a mean cost per patient of 52,555 $ (40,542 €). The mean cost per patient was 24,980 $ (19,270.80 €) for patients with early PJI and rose to 78,111 $ (60,257 €) for those with late PJI. The main cost was for the hospital stay and the specific in-hospital care received, followed by the cost of the surgical procedure.


Assuntos
Prótese do Joelho , Complicações Pós-Operatórias/economia , Infecções Relacionadas à Prótese/economia , Saúde Pública/economia , Idoso , Antibacterianos/economia , Artroplastia do Joelho/economia , Distribuição de Qui-Quadrado , Remoção de Dispositivo/economia , Diagnóstico por Imagem/economia , Feminino , Humanos , Tempo de Internação/economia , Masculino , Infecções Relacionadas à Prótese/terapia , Reoperação/economia , Estudos Retrospectivos , Fatores de Risco , Espanha
10.
Rev Gastroenterol Mex ; 78(2): 92-113, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-23664429

RESUMO

The aim of the Mexican Consensus on Portal Hypertension was to develop documented guidelines to facilitate clinical practice when dealing with key events of the patient presenting with portal hypertension and variceal bleeding. The panel of experts was made up of Mexican gastroenterologists, hepatologists, and endoscopists, all distinguished professionals. The document analyzes themes of interest in the following modules: preprimary and primary prophylaxis, acute variceal hemorrhage, and secondary prophylaxis. The management of variceal bleeding has improved considerably in recent years. Current information indicates that the general management of the cirrhotic patient presenting with variceal bleeding should be carried out by a multidisciplinary team, with such an approach playing a major role in the final outcome. The combination of drug and endoscopic therapies is recommended for initial management; vasoactive drugs should be started as soon as variceal bleeding is suspected and maintained for 5 days. After the patient is stabilized, urgent diagnostic endoscopy should be carried out by a qualified endoscopist, who then performs the corresponding endoscopic variceal treatment. Antibiotic prophylaxis should be regarded as an integral part of treatment, started upon hospital admittance and continued for 5 days. If there is treatment failure, rescue therapies should be carried out immediately, taking into account that interventional radiology therapies are very effective in controlling refractory variceal bleeding. These guidelines have been developed for the purpose of achieving greater clinical efficacy and are based on the best evidence of portal hypertension that is presently available.


Assuntos
Hipertensão Portal/diagnóstico , Hipertensão Portal/terapia , Árvores de Decisões , Varizes Esofágicas e Gástricas/etiologia , Hemorragia Gastrointestinal/etiologia , Humanos , Hipertensão Portal/complicações , México
11.
Rev Sci Instrum ; 93(2): 024704, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35232123

RESUMO

The search for new technologies aiming to reach radiofrequency (RF) generation in different manners for diverse ends is a constant demand for several applications. The goal is to develop cost-effective and simpler systems compared to those that already exist. Our motivation is to reach an alternative way of generating RF in pulsed transmission systems employing a gyromagnetic nonlinear transmission line (GNLTL). The GNLTL consists of a ferrite-loaded-coaxial transmission line and can produce a large frequency spectrum with RF conversion efficiency above 10% from about 200 MHz up to the frequency of 2-4 GHz (S-band) for potential space-based applications. In a GNLTL, the signal amplitude is related to its propagation velocity since the peak voltage travels faster than its portion of lower amplitudes since the ferrite permeability decreases with the current amplitude. As the pulse crest travels faster than its valley, a time reduction happens in the output rise time, called pulse sharpening. Besides, the magnetic moments of ferrite dipoles initially aligned with the axial magnetic bias are displaced from their original position by the azimuthal field generated around the inner conductor by the current pulse, resulting in a damped precession movement. This movement happens along the line length as the current pulse propagates, inducing high-frequency oscillations. In short, the paper's goal is to present the experimental results using a 60-cm gyromagnetic line to provide RF in the GHz range using a solenoid for magnetic bias on a testing bench. Finally, the paper discusses the influence of the azimuthal and the axial magnetic fields on the output signal with the ferrite rings operating in a saturation state during the current pulse propagation.

12.
Rehabilitacion (Madr) ; 55(3): 238-240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33276984

RESUMO

Rotator cuff muscle tear is a common finding among adults and acromioclavicular cyst is a rare secondary manifestation. This case report describes the clinical presentation and workup diagnosis of a patient with acromioclavicular cyst in context of massive rotator cuff tear. Woman, 83-year-old developed a tumefaction over the left acromioclavicular joint. She had pain, limitation on active range of motion and function limitation of the left shoulder. The X-ray revealed superior humeral head displacement and signs of arthropathy. The MRI revealed "geyser sign" and identified an acromioclavicular cyst secondary to cuff tear arthropathy. Aspiration was not performed due to high recurrence rate and surgical removal was decided. Clinicians should be aware of this rare complication of rotator cuff tear, demanding exclusion of other possible causes of acromioclavicular cyst and offer suitable treatment options.


Assuntos
Articulação Acromioclavicular , Cistos , Lesões do Manguito Rotador , Articulação Acromioclavicular/diagnóstico por imagem , Articulação Acromioclavicular/cirurgia , Idoso de 80 Anos ou mais , Cistos/complicações , Cistos/diagnóstico por imagem , Cistos/cirurgia , Feminino , Humanos , Recidiva Local de Neoplasia , Manguito Rotador/diagnóstico por imagem , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/diagnóstico , Lesões do Manguito Rotador/diagnóstico por imagem
13.
Domest Anim Endocrinol ; 74: 106526, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810656

RESUMO

This study investigated the effects of growth rates and compensatory growth on puberty attainment in Nellore heifers. Nellore heifers (n = 120), weaned at 8 ± 0.75 mo of age, were blocked by sire and BW (180 ± 8.6 kg) and assigned randomly to receive 1 of 4 treatments over a 10-mo period. Treatments included ad libitum feeding (high gain, HG), feed intake to gain 0.6 kg/d (medium gain, MG), restricted feeding (0.2 kg/d) for 4 mo followed by ad libitum feeding for 6 mo (compensatory gain, CG), and alternating periods of ad libitum and restricted feeding for 2 mo each throughout the trial (alternated CG, ACG). Puberty was assessed weekly by transrectal ultrasonography. Blood samples were collected at 8, 11, and 18 mo of age and at puberty to determine circulating concentrations of leptin. At 18 mo of age, nonpubertal heifers were treated with a puberty induction protocol using an intravaginal progestin device. There was no treatment effect (P = 0.17) on the percentage of heifers pubertal by 18 mo of age (HG: 66, MG: 40, CG: 58, and ACG: 52%), BW at puberty, and age at puberty. However, HG heifers had higher ADG (P < 0.01), dry matter intake (P < 0.01), and leptin concentrations (P = 0.03) than heifers from other groups. The response to the puberty induction protocol was similar (P = 0.90) among treatments. Regarding sire effects (genetic effects), there was an effect (P = 0.03) on the percentage of heifers pubertal by 18 mo of age and a tendency (P = 0.07) of sire effect in response to the puberty induction protocol. Compensatory growth appears to be an effective managerial approach to decrease feeding costs and stimulate puberty in Nellore heifers.


Assuntos
Restrição Calórica , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Leptina/sangue , Maturidade Sexual/efeitos dos fármacos , Envelhecimento , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Leptina/metabolismo , Aumento de Peso/efeitos dos fármacos
14.
Artigo em Inglês | MEDLINE | ID: mdl-20606293

RESUMO

The flagellated protozoan parasite Trypanosoma cruzi is the aetiological agent of Chagas disease. Nucleoside diphosphate kinases (NDPKs) are enzymes that are involved in energy management and nucleoside balance in the cell. T. cruzi TcNDPK1, a canonical isoform, was overexpressed in Escherichia coli as an N-terminally poly-His-tagged fusion protein and crystallized. Crystals grew after 72 h in 0.2 M MgCl(2), 20% PEG 3350. Data were collected to 3.5 A resolution using synchrotron X-ray radiation at the National Synchrotron Light Laboratory (Campinas, Brazil). The crystals belonged to the trigonal space group P3, with unit-cell parameters a = b = 127.84, c = 275.49 A. Structure determination is under way and will provide relevant information that may lead to the first step in rational drug design for the treatment of Chagas disease.


Assuntos
Núcleosídeo-Difosfato Quinase/química , Trypanosoma cruzi/enzimologia , Cristalização , Cristalografia por Raios X
15.
J Nematol ; 42(1): 8-16, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22736831

RESUMO

Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, were screened for their nematicidal activity against the pinewood nematode (PWN), Bursaphelenchus xylophilus. The essential oils were isolated by hydrodistillation and the volatiles by distillation-extraction, and both were analysed by GC and GC-MS. High nematicidal activity was achieved with essential oils from Chamaespartium tridentatum, Origanum vulgare, Satureja montana, Thymbra capitata, and Thymus caespititius. All of these essential oils had an estimated minimum inhibitory concentration ranging between 0.097 and 0.374 mg/ml and a lethal concentration necessary to kill 100% of the population (LC(100)) between 0.858 and 1.984 mg/ml. Good nematicidal activity was also obtained with the essential oil from Cymbopogon citratus. The dominant components of the effective oils were 1-octen-3-ol (9%), n-nonanal, and linalool (both 7%) in C. tridentatum, geranial (43%), neral (29%), and ß-myrcene (25%) in C. citratus, carvacrol (36% and 39%), γ-terpinene (24% and 40%), and p-cymene (14% and 7%) in O. vulgare and S. montana, respectively, and carvacrol (75% and 65%, respectively) in T. capitata and T. caespititius. The other essential oils obtained from Portuguese flora yielded weak or no activity. Five essential oils with nematicidal activity against PWN are reported for the first time.

16.
Eur J Neurol ; 15(10): 1091-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18727673

RESUMO

BACKGROUND AND PURPOSE: We have studied the relationship between neuropsychological impairment and magnetic resonance imaging (MRI) measures in mildly disabling relapsing-remitting multiple sclerosis (RRMS). METHODS: We compared measures of lesion burden and atrophy in 52 patients with Expanded Disability Status Scale

Assuntos
Encéfalo/patologia , Transtornos Cognitivos/patologia , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto , Atrofia , Atenção , Ventrículos Cerebrais/patologia , Transtornos Cognitivos/etiologia , Corpo Caloso/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Esclerose Múltipla Recidivante-Remitente/psicologia , Testes Neuropsicológicos , Desempenho Psicomotor , Índice de Gravidade de Doença , Aprendizagem Verbal
17.
AIDS Care ; 20(10): 1258-65, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18608079

RESUMO

Despite the fact that fatigue is a common and debilitating symptom among HIV-infected persons, we know little about the predictors of fatigue in this population. The goal of this cross-sectional study was to examine the effects of early childhood trauma, recent stressful life events and depression on intensity and impairment of fatigue in HIV, over and above demographic factors and clinical characteristics. We studied 128 HIV-infected men and women from one southern state. The median number of childhood traumatic events was two and participants tended to have at least one moderate recent stressful event. Multiple regression findings showed that patients with less income, more childhood trauma, more recent stressful events and more depressive symptoms had greater fatigue intensity and fatigue-related impairment in daily functioning. Recent stresses were a more powerful predictor of fatigue than childhood trauma. None of the disease-related measures (e.g. CD4, viral load, antiretroviral medication) predicted fatigue. Although stress and trauma have been related to fatigue in other populations, this is the first study to examine the effects of traumatic and recent stressful life events on fatigue in an HIV-infected sample.


Assuntos
Transtorno Depressivo/psicologia , Fadiga/psicologia , Infecções por HIV/psicologia , Acontecimentos que Mudam a Vida , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Idoso , Criança , Estudos Transversais , Fadiga/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
AIDS Care ; 20(7): 829-37, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18608084

RESUMO

In the era of life-prolonging antiretroviral therapy, chronic fatigue is one of the most prevalent and disabling symptoms of people living with HIV/AIDS, yet its measurement remains challenging. No instruments have been developed specifically to describe HIV-related fatigue. We assessed the reliability and construct validity of the HIV-Related Fatigue Scale (HRFS), a 56-item self-report instrument developed through formative qualitative research and designed to measure the intensity and consequences of fatigue as well as the circumstances surrounding fatigue in people living with HIV. The HRFS has three main scales, which measure fatigue intensity, the responsiveness of fatigue to circumstances and fatigue-related impairment of functioning. The functioning scale can be further divided into subscales measuring impairment of activities of daily living, impairment of mental functioning and impairment of social functioning. Each scale demonstrated high internal consistency (Cronbach's alpha=0.93, 0.91 and 0.97 for the intensity, responsiveness and functioning scales, respectively). The HRFS scales also demonstrated satisfactory convergent validity when compared to other fatigue measures. HIV-Related Fatigue Scales were moderately correlated with quality of nighttime sleep (rho=0.46, 0.47 and 0.35) but showed only weak correlations with daytime sleepiness (rho=0.20, 0.33 and 0.18). The scales were also moderately correlated with general mental and physical health as measured by the SF-36 Health Survey (rho ranged from 0.30 to 0.68 across the 8 SF-36 subscales with most >0.40). The HRFS is a promising tool to help facilitate research on the prevalence, etiology and consequences of fatigue in people living with HIV.


Assuntos
Atividades Cotidianas , Fadiga/diagnóstico , Infecções por HIV/complicações , HIV-1 , Adulto , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Masculino , Psicometria/métodos , Projetos de Pesquisa , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Sudeste dos Estados Unidos , Inquéritos e Questionários
19.
Toxicol In Vitro ; 50: 62-74, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29501630

RESUMO

This report describes the proceedings of the BfR-RIVM workshop on validation of alternative methods which was held 23 and 24 March 2017 in Berlin, Germany. Stakeholders from governmental agencies, regulatory authorities, universities, industry and the OECD were invited to discuss current problems concerning the regulatory acceptance and implementation of alternative test methods and testing strategies, with the aim to develop feasible solutions. Classical validation of alternative methods usually involves one to one comparison with the gold standard animal study. This approach suffers from the reductionist nature of an alternative test as compared to the animal study as well as from the animal study being considered as the gold standard. Modern approaches combine individual alternatives into testing strategies, for which integrated and defined approaches are emerging at OECD. Furthermore, progress in mechanistic toxicology, e.g. through the adverse outcome pathway approach, and in computational systems toxicology allows integration of alternative test battery results into toxicity predictions that are more fine-tuned to the human situation. The road towards transition to a mechanistically-based human-focused hazard and risk assessment of chemicals requires an open mind towards stepping away from the animal study as the gold standard and defining human biologically based regulatory requirements for human hazard and risk assessment.


Assuntos
Alternativas aos Testes com Animais/métodos , Medição de Risco/métodos , Testes de Toxicidade/métodos , Animais , Órgãos Governamentais , Humanos , Reprodutibilidade dos Testes
20.
Rev Neurol ; 65(6): 241-248, 2017 Sep 16.
Artigo em Espanhol | MEDLINE | ID: mdl-28895997

RESUMO

INTRODUCTION: Stroke is one of the main causes of mortality and functional disability in developed countries. Carotid stenosis (CS) is considered the reason for 20-30% of strokes. However, the studies that have gone into depth on the cognitive status of these patients are limited. AIM: To investigate the cognitive performance of CS patients and its relationship with clinical variables (carotid obstruction, lifestyle). PATIENTS AND METHODS: 33 CS patients were evaluated using a broad neuropsychological protocol, and were divided into two groups: symptomatic CS and asymptomatic CS. RESULTS: 50-57% of CS patients showed deficits in processing speed and visual memory (immediate recall). 41.9% showed altered performance in semantic fluency, whereas the percentage was 30% in digits subtest. The percentage of altered performance was 20-27% in verbal memory (learning curve, delayed recall) and visual memory (delayed recall). No significant differences were found between the symptomatic CS and asymptomatic CS groups. Cognitive performance correlated significantly with lifestyle scale factors, but not with the percentage of carotid obstruction. CONCLUSION: A high percentage of CS patients showed a clinically altered performance in different cognitive domains, regardless of suffering vascular neurological symptoms (symptomatic vs asymptomatic CS). A close relationship was found between lifestyle and cognitive status of CS patients.


TITLE: Elevada incidencia de deterioro cognitivo en pacientes con estenosis carotidea asintomatica.Introduccion. Los ictus se situan como una de las principales causas de mortalidad e incapacidad funcional en los paises desarrollados. La estenosis carotidea (EC) se considera la causa del 20-30% de los ictus. No obstante, los estudios que han profundizado en el estado cognitivo de estos pacientes son escasos. Objetivo. Estudiar el rendimiento cognitivo de pacientes con EC y su relacion con variables clinicas (obstruccion de la carotida, estilo de vida). Pacientes y metodos. Se evaluo a 33 pacientes con EC mediante un protocolo neuropsicologico amplio, distribuidos en dos grupos: EC sintomatica y EC asintomatica. Resultados. Un 50-57% de los pacientes con EC presento una ejecucion alterada en velocidad de procesamiento y memoria visual (recuerdo inmediato). Un 41,9% rindio de forma alterada en fluidez semantica, mientras que en el subtest de digitos el porcentaje fue del 30%. En la memoria verbal (curva de aprendizaje, recuerdo demorado) y la memoria visual (recuerdo demorado), el porcentaje de alterados fue del 20-27%. No se encontraron diferencias significativas entre los grupos de EC asintomatica y EC sintomatica. El rendimiento cognitivo correlaciono significativamente con los factores de la escala de estilo de vida, pero no con el porcentaje de obstruccion de la carotida. Conclusion. Un elevado porcentaje de los pacientes con EC presento un rendimiento clinicamente alterado en diferentes dominios cognitivos, con independencia de que hubieran experimentado o no sintomatologia neurologica vascular (EC asintomatica frente a sintomatica). Se encontro una estrecha relacion entre el estilo de vida y el estado cognitivo de los pacientes con EC.


Assuntos
Doenças Assintomáticas , Estenose das Carótidas/complicações , Disfunção Cognitiva/complicações , Disfunção Cognitiva/epidemiologia , Idoso , Estenose das Carótidas/diagnóstico , Feminino , Humanos , Incidência , Estilo de Vida , Masculino
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