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1.
Artigo em Russo | MEDLINE | ID: mdl-34665551

RESUMO

The article presents the results of the study of factors effecting on professional deformation of stomatologists and its relationship with their personal characteristics, labor experience and medical specialization. the information is compiled with purpose of elaborating comprehensive recommendations on diagnostics of phases of development of syndrome of emotional burnout in this category of medical specialists at the initial stages of its occurrence and proposing measures of its adjustment including social and personal prevention.


Assuntos
Esgotamento Profissional , Medicina , Esgotamento Profissional/epidemiologia , Esgotamento Psicológico/epidemiologia , Emoções , Humanos , Especialização , Inquéritos e Questionários
2.
Probl Sotsialnoi Gig Zdravookhranenniiai Istor Med ; 28(Special Issue): 741-747, 2020 Aug.
Artigo em Russo | MEDLINE | ID: mdl-32856818

RESUMO

The article presents the results of the author's research that determines the degree of influence of monotonous (monotonous) labor processes on the drivers (and their assistants) of traction rolling stock of railway transport. Information is collected in order to develop a set of measures to overcome the monotony of work, improve the quality of working life and psychophysiological health of employees, and as a result, ensure traffic safety, improving the safety system for drivers and improving the quality of passenger transport.


Assuntos
Estresse Ocupacional , Ferrovias , Humanos , Estresse Psicológico
3.
Gene Ther ; 23(3): 237-46, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26588709

RESUMO

Small caliber synthetic vascular grafts are commonly used for bypass surgery and dialysis access sites but have high failure rates because of neointima formation and thrombosis. Seeding synthetic grafts with endothelial cells (ECs) provides a biocompatible surface that may prevent graft failure. However, EC detachment following exposure to blood flow still remains a major obstacle in the development of biosynthetic grafts. We tested the hypothesis that induced expression by the seeded EC, of vascular endothelial growth factor165 (VEGF165) and of fibulin-5, an extracellular matrix glycoprotein that has a crucial role in elastin fiber organization and increase EC adherence to surfaces, may improve long-term graft patency. Autologous ECs were isolated from venous segments, and were transduced with retroviral vectors expressing fibulin-5 and VEGF165. The modified cells were seeded on expanded polytetrafluoroethylene (ePTFE) grafts and implanted in a large animal model. Three months after transplantation, all grafts seeded with modified EC were patent on a selective angiography, whereas only a third of the control grafts were patent. Similar results were shown at 6 months. Thus, seeding ePTFE vascular grafts with genetically modified EC improved long-term small caliber graft patency. The biosynthetic grafts may provide a novel therapeutic modality for patients with peripheral vascular disease and patients requiring vascular access for hemodialysis.


Assuntos
Células Endoteliais/transplante , Proteínas da Matriz Extracelular/uso terapêutico , Doenças Vasculares Periféricas/terapia , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Enxerto Vascular/métodos , Animais , Células Endoteliais/fisiologia , Proteínas da Matriz Extracelular/genética , Humanos , Modelos Animais , Ratos , Ovinos , Fator A de Crescimento do Endotélio Vascular/genética , Grau de Desobstrução Vascular
4.
Chromosome Res ; 23(2): 311-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25783786

RESUMO

Urothelial carcinoma (UC), also referred to as transitional cell carcinoma (TCC), is the most common bladder malignancy in both human and canine populations. In human UC, numerous studies have demonstrated the prevalence of chromosomal imbalances. Although the histopathology of the disease is similar in both species, studies evaluating the genomic profile of canine UC are lacking, limiting the discovery of key comparative molecular markers associated with driving UC pathogenesis. In the present study, we evaluated 31 primary canine UC biopsies by oligonucleotide array comparative genomic hybridization (oaCGH). Results highlighted the presence of three highly recurrent numerical aberrations: gain of dog chromosome (CFA) 13 and 36 and loss of CFA 19. Regional gains of CFA 13 and 36 were present in 97 % and 84 % of cases, respectively, and losses on CFA 19 were present in 77 % of cases. Fluorescence in situ hybridization (FISH), using targeted bacterial artificial chromosome (BAC) clones and custom Agilent SureFISH probes, was performed to detect and quantify these regions in paraffin-embedded biopsy sections and urine-derived urothelial cells. The data indicate that these three aberrations are potentially diagnostic of UC. Comparison of our canine oaCGH data with that of 285 human cases identified a series of shared copy number aberrations. Using an informatics approach to interrogate the frequency of copy number aberrations across both species, we identified those that had the highest joint probability of association with UC. The most significant joint region contained the gene PABPC1, which should be considered further for its role in UC progression. In addition, cross-species filtering of genome-wide copy number data highlighted several genes as high-profile candidates for further analysis, including CDKN2A, S100A8/9, and LRP1B. We propose that these common aberrations are indicative of an evolutionarily conserved mechanism of pathogenesis and harbor genes key to urothelial neoplasia, warranting investigation for diagnostic, prognostic, and therapeutic applications.


Assuntos
Carcinoma/veterinária , Aberrações Cromossômicas , Hibridização Genômica Comparativa , Neoplasias Urológicas/veterinária , Animais , Biópsia , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Cães , Feminino , Loci Gênicos , Genômica/métodos , Humanos , Hibridização in Situ Fluorescente , Masculino
5.
Vet Pathol ; 53(4): 764-72, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26574558

RESUMO

Urothelial carcinoma (UC) is the most common neoplasm of the canine urinary tract. Clinical presentation of UC is shared with several other, more common urinary tract disorders, and this often delays diagnosis of the UC. Definitive diagnosis of UC requires histopathologic examination of a biopsy specimen, but the cost and invasiveness for these diagnostic tests often result in most diagnoses being made on the basis of clinical findings, diagnostic imaging, and cytologic examination of urine sediment. Regardless of the diagnostic process used, most UCs currently are not diagnosed until they are at an advanced clinical stage and so are associated with poor prognosis. Improved methods for earlier and less invasive detection are needed. In a previous study, the authors demonstrated the presence of highly recurrent DNA copy number aberrations (CNAs) in canine UC and hypothesized that detection of these CNAs in tumor cells can be used as a molecular diagnostic for UC. In this study, a multiplexed droplet digital polymerase chain reaction (ddPCR) assay was detected to detect and quantify CNAs of specific regions of canine chromosomes 8, 13, 19, and 36. The assay was effective at differentiating 31 neoplastic and 25 nonneoplastic bladder tissues based on copy number, with 100% sensitivity and specificity in tissue samples. CNAs were also detected by ddPCR in 67% (12 of 18) of urine DNA specimens derived from UC patients. The findings show that ddPCR is a useful molecular technique to detect CNAs and may be used as a noninvasive molecular diagnostic test for canine UC.


Assuntos
Carcinoma de Células de Transição/veterinária , Doenças do Cão/genética , Neoplasias da Bexiga Urinária/veterinária , Neoplasias Urológicas/veterinária , Animais , Carcinoma de Células de Transição/diagnóstico , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , Hibridização Genômica Comparativa/veterinária , Variações do Número de Cópias de DNA , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Reação em Cadeia da Polimerase/veterinária , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/genética , Neoplasias Urológicas/patologia
6.
Climacteric ; 18(4): 441-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25962085

RESUMO

There is no debate any more on the good safety profile of postmenopausal hormone therapy (HT) in healthy perimenopausal and early postmenopausal women, but there are still many open issues related to the consequences of long-term HT, especially in older women. A recent Cochrane meta-analysis showed that women who started HT less than 10 years after the menopause had lower mortality and coronary heart disease (CHD), but more venous thromboembolism (DVT). However, in those who started treatment more than 10 years after the menopause, there was high-quality evidence that it had little effect on death or CHD between HT and placebo groups but there was an increased risk of stroke and DVT. In contrast, many large, observational studies such as a recent one from Finland (3.3 million years of HT exposure) have shown that the risk of CHD or stroke death and all-cause mortality was significantly reduced, both in those who initiated HT below or above age 60 years. Because of conflicting data concerning long-term HT use, it seems that every health-care provider chooses as reference those studies that can support his/her individual views and therapeutic approach.


Assuntos
Doenças Cardiovasculares/induzido quimicamente , Terapia de Reposição de Estrogênios/efeitos adversos , Fatores Etários , Idoso , Viés , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Esquema de Medicação , Terapia de Reposição de Estrogênios/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Medição de Risco , Fatores de Tempo
7.
Climacteric ; 17(3): 215-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24654673

RESUMO

BACKGROUND: In an integrated overview of the benefits and risks of menopausal hormone therapy (HT), the Women's Health Initiative (WHI) investigators have claimed that their 'findings … do not support use of this therapy for chronic disease prevention'. In an accompanying editorial, it was claimed that 'the WHI overturned medical dogma regarding menopausal [HT]'. OBJECTIVES: To evaluate those claims. METHODS: Epidemiological criteria of causation were applied to the evidence. RESULTS: A 'global index' purporting to summarize the overall benefit versus the risk of HT was not valid, and it was biased. For coronary heart disease, an increased risk in users of estrogen plus progestogen (E + P), previously reported by the WHI, was not confirmed. The WHI study did not establish that E+ P increases the risk of breast cancer; the findings suggest that unopposed estrogen therapy (ET) does not increase the risk, and may even reduce it. The findings for stroke and pulmonary embolism were compatible with an increased risk, and among E+ P users there were credible reductions in the risk of colorectal and endometrial cancer. For E+ P and ET users, there were credible reductions in the risk of hip fracture. Under 'worst case' and 'best case' assumptions, the changes in the incidence of the outcomes attributable to HT were minor. CONCLUSIONS: Over-interpretation and misrepresentation of the WHI findings have damaged the health and well-being of menopausal women by convincing them and their health professionals that the risks of HT outweigh the benefits.


Assuntos
Neoplasias da Mama/epidemiologia , Doença das Coronárias/epidemiologia , Interpretação Estatística de Dados , Estrogênios/uso terapêutico , Terapia de Reposição Hormonal , Progestinas/uso terapêutico , Viés , Neoplasias da Mama/induzido quimicamente , Fatores de Confusão Epidemiológicos , Doença das Coronárias/induzido quimicamente , Estrogênios/efeitos adversos , Feminino , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Menopausa , Progestinas/efeitos adversos , Medição de Risco
8.
Climacteric ; 17(5): 540-56, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24969415

RESUMO

Women may expect to spend more than a third of their lives after menopause. Beginning in the sixth decade, many chronic diseases will begin to emerge, which will affect both the quality and quantity of a woman's life. Thus, the onset of menopause heralds an opportunity for prevention strategies to improve the quality of life and enhance longevity. Obesity, metabolic syndrome and diabetes, cardiovascular disease, osteoporosis and osteoarthritis, cognitive decline, dementia and depression, and cancer are the major diseases of concern. Prevention strategies at menopause have to begin with screening and careful assessment for risk factors, which should also include molecular and genetic diagnostics, as these become available. Identification of certain risks will then allow directed therapy. Evidence-based prevention for the diseases noted above include lifestyle management, cessation of smoking, curtailing excessive alcohol consumption, a healthy diet and moderate exercise, as well as mentally stimulating activities. Although the most recent publications from the follow-up studies of the Women's Health Initiative do not recommend menopause hormonal therapy as a prevention strategy, these conclusions may not be fully valid for midlife women, on the basis of the existing data. For healthy women aged 50-59 years, estrogen therapy decreases coronary heart disease and all-cause mortality; this interpretation is entirely consistent with results from other randomized, controlled trials and observational studies. Thus. as part of a comprehensive strategy to prevent chronic disease after menopause, menopausal hormone therapy, particularly estrogen therapy may be considered as part of the armamentarium.


Assuntos
Doença Crônica/prevenção & controle , Pós-Menopausa , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Doença Crônica/epidemiologia , Demência/epidemiologia , Demência/etiologia , Demência/prevenção & controle , Diagnóstico Precoce , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Menopausa , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/prevenção & controle , Obesidade/epidemiologia , Obesidade/etiologia , Obesidade/prevenção & controle , Osteoartrite/epidemiologia , Osteoartrite/etiologia , Osteoartrite/prevenção & controle , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/prevenção & controle , Qualidade de Vida , Fatores de Risco , Comportamento de Redução do Risco , Saúde da Mulher
9.
Arthritis Rheum ; 64(12): 4072-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22777623

RESUMO

OBJECTIVE: Exercise-induced pulmonary hypertension (ePH) may represent an early, clinically relevant phase in the spectrum of pulmonary vascular disease. The purpose of this pilot study was to describe the changes in hemodynamics and exercise capacity in patients with systemic sclerosis (SSc) spectrum-associated ePH treated with open-label daily ambrisentan. METHODS: Patients were treated with ambrisentan, 5 mg or 10 mg once daily, for 24 weeks. At baseline and 24 weeks, patients with SSc spectrum disorders exercised in a supine position, on a lower extremity cycle ergometer. All patients had normal hemodynamics at rest. We defined baseline ePH as a mean pulmonary artery pressure of >30 mm Hg with maximum exercise and a transpulmonary gradient (TPG) of >15 mm Hg. The primary end point was change in pulmonary vascular resistance (PVR) with exercise. Secondary end points included an improvement from baseline in 6-minute walking distance, health-related quality of life assessments, and cardiopulmonary hemodynamics. RESULTS: Of the 12 enrolled patients, 11 completed the study. At 24 weeks there were improvements in mean exercise PVR (85.8 dynes × second/cm(5) ; P = 0.003) and mean distance covered during 6-minute walk (44.5 meters; P = 0.0007). Improvements were also observed in mean exercise cardiac output (1.4 liters/minute; P = 0.006), mean pulmonary artery pressure (-4.1 mm Hg; P = 0.02), and total pulmonary resistance (-93.0 dynes × seconds/cm(5) ; P = 0.0008). Three patients developed resting pulmonary arterial hypertension during the 24 weeks. CONCLUSION: Exercise hemodynamics and exercise capacity in patients with SSc spectrum-associated ePH improved over 24 weeks with exposure to ambrisentan. Placebo-controlled studies are needed to confirm whether this is a drug-related effect and to determine optimal therapeutic regimens for patients with ePH.


Assuntos
Anti-Hipertensivos/uso terapêutico , Exercício Físico/fisiologia , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Fenilpropionatos/uso terapêutico , Piridazinas/uso terapêutico , Escleroderma Sistêmico/complicações , Adulto , Idoso , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Débito Cardíaco/efeitos dos fármacos , Débito Cardíaco/fisiologia , Relação Dose-Resposta a Droga , Feminino , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenilpropionatos/efeitos adversos , Fenilpropionatos/farmacologia , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Projetos Piloto , Estudos Prospectivos , Piridazinas/efeitos adversos , Piridazinas/farmacologia , Qualidade de Vida , Resultado do Tratamento
10.
Climacteric ; 16(5): 522-35, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23931571

RESUMO

The onset of the menopause is often a time when women's concerns can act as a powerful trigger to encourage healthy modifications in lifestyle which will maintain, or improve, their general health. This document aims to help women to understand their potential risks, to encourage them to find proactive preventive strategies by modifying some of their attitudes, and to use health resources (when available) to be screened. Cancer is an important cause of death but not the primary cause of mortality. Cardio/circulatory diseases represent 35-40% of causes of death in most developed countries and 20-25% of women will die from cancers in Western Europe, Australasia, high-income North America, high-income Asia Pacific, East Asia and Southern Latin America. Breast cancer, lung cancer and colorectal cancer are prevalent in most regions of the world. Cervical cancer remains a hallmark of low access to health care. Preventive strategies (decreasing smoking and alcohol consumption, losing weight, eating a healthy diet and undertaking physical activity) and implementation of screening could help to significantly decrease the incidence of and mortality from cancer. The mortality/incidence ratio is higher in developing countries compared to high-income regions as well as in subgroups of populations in developed countries with lower socioeconomic levels. Implementation of better diagnostic methods and management of cancer according to the local resources will help to decrease the mortality rate in developing countries, and effort has to be made to decrease social inequities and improve access to health care for low-income groups. In conclusion, cancer incidence is increasing as a consequence of longer life expectancy all over the world. National health programs are mandatory to implement screening and to improve individual management. Finally, educating women so that they are aware of ways to improve their general health, to minimize their own risk factors and to identify signs of change in their own health which may be markers of impending cancer will help to reduce the burden of disease and improve the prognosis for tumors detected at an earlier stage.


Assuntos
Menopausa , Neoplasias , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias Colorretais/epidemiologia , Dieta , Neoplasias do Endométrio/epidemiologia , Etnicidade , Feminino , Promoção da Saúde , Humanos , Renda , Expectativa de Vida , Estilo de Vida , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Neoplasias/mortalidade , Neoplasias/prevenção & controle , Obesidade/complicações , Neoplasias Ovarianas , Neoplasias do Colo do Útero/epidemiologia
11.
Nat Genet ; 17(4): 439-44, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9398846

RESUMO

The molecular mechanisms predisposing to atherosclerotic aneurysm formation remain undefined. Nevertheless, rupture of aortic aneurysms is a major cause of death in Western societies, with few available treatments and poor long-term prognosis. Indirect evidence suggests that matrix metalloproteinases (MMPs) and plasminogen activators (PAs) are involved in its pathogenesis. MMPs are secreted as inactive zymogens (pro-MMPs), requiring activation in the extracellular compartment. Plasmin, generated from the zymogen plasminogen by tissue-type plasminogen activator (t-PA) or urokinase-type plasminogen activator (u-PA; refs 14,15), has been proposed as a possible activator in vitro, but evidence for such a role in vivo is lacking. Analysis of atherosclerotic aorta in mice with a deficiency of apoliprotein E (Apoe-/-; ref. 18), singly or combined with a deficiency of t-PA (Apoe-/-:Plat-/-) or of u-PA (Apoe-/-:Plau-/-; ref. 19), indicated that deficiency of u-PA protected against media destruction and aneurysm formation, probably by means of reduced plasmin-dependent activation of pro-MMPs. This genetic evidence suggests that plasmin is a pathophysiologically significant activator of pro-MMPs in vivo and may have implications for the design of therapeutic strategies to prevent aortic-wall destruction by controlling Plau gene function.


Assuntos
Aneurisma da Aorta Abdominal/enzimologia , Aneurisma da Aorta Torácica/enzimologia , Fibrinolisina/metabolismo , Metaloendopeptidases/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Animais , Aneurisma da Aorta Abdominal/etiologia , Aneurisma da Aorta Abdominal/patologia , Aneurisma da Aorta Torácica/etiologia , Aneurisma da Aorta Torácica/patologia , Arteriosclerose/enzimologia , Arteriosclerose/patologia , Colágeno/metabolismo , Dieta Aterogênica , Elastina/metabolismo , Ativação Enzimática , Feminino , Macrófagos/enzimologia , Masculino , Camundongos , Camundongos Knockout , Túnica Média/enzimologia , Túnica Média/patologia
12.
Am J Physiol Lung Cell Mol Physiol ; 303(10): L852-60, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22962014

RESUMO

Efferocytosis is believed to be a key regulator for lung inflammation in chronic obstructive pulmonary disease. In this study we pharmacologically inhibited efferocytosis with annexin V and attempted to determine its impact on the progression of pulmonary emphysema in mouse. We first demonstrated in vitro and in vivo efferocytosis experiments using annexin V, an inhibitor for phosphatidylserine-mediated efferocytosis. We then inhibited efferocytosis in porcine pancreatic elastase (PPE)-treated mice. PPE-treated mice were instilled annexin V intranasally starting from day 8 until day 20. Mean linear intercept (Lm) was measured, and cell apoptosis was assessed in lung specimen obtained on day 21. Cell profile, apoptosis, and mRNA expression of matrix metalloproteinases (MMPs) and growth factors were evaluated in bronchoalveolar lavage (BAL) cells on day 15. Annexin V attenuated macrophage efferocytosis both in vitro and in vivo. PPE-treated mice had a significant higher Lm, and annexin V further increased that by 32%. More number of macrophages was found in BAL fluid in this group. Interestingly, cell apoptosis was not increased by annexin V treatment both in lung specimens and BAL fluid, but macrophages from mice treated with both PPE and annexin V expressed higher MMP-2 mRNA levels and had a trend for higher MMP-12 mRNA expression. mRNA expression of keratinocyte growth factor tended to be downregulated. We showed that inhibited efferocytosis with annexin V worsened elastase-induced pulmonary emphysema in mice, which was, at least partly, attributed to a lack of phenotypic change in macrophages toward anti-inflammatory one.


Assuntos
Anexina A5/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos Alveolares/enzimologia , Elastase Pancreática/efeitos adversos , Enfisema Pulmonar/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Lavagem Broncoalveolar , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Macrófagos Alveolares/patologia , Metaloproteinase 12 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/biossíntese , Camundongos , Elastase Pancreática/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/enzimologia , Doença Pulmonar Obstrutiva Crônica/patologia , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/enzimologia , Enfisema Pulmonar/patologia , RNA Mensageiro/biossíntese , Suínos
13.
Osteoarthritis Cartilage ; 20(8): 896-905, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22531458

RESUMO

OBJECTIVE: To investigate the mechanisms by which chronic tobacco smoking promotes intervertebral disc degeneration (IDD) and vertebral degeneration in mice. METHODS: Three month old C57BL/6 mice were exposed to tobacco smoke by direct inhalation (4 cigarettes/day, 5 days/week for 6 months) to model long-term smoking in humans. Total disc proteoglycan (PG) content [1,9-dimethylmethylene blue (DMMB) assay], aggrecan proteolysis (immunobloting analysis), and cellular senescence (p16INK4a immunohistochemistry) were analyzed. PG and collagen syntheses ((35)S-sulfate and (3)H-proline incorporation, respectively) were measured using disc organotypic culture. Vertebral osteoporosity was measured by micro-computed tomography. RESULTS: Disc PG content of smoke-exposed mice was 63% of unexposed control, while new PG and collagen syntheses were 59% and 41% of those of untreated mice, respectively. Exposure to tobacco smoke dramatically increased metalloproteinase-mediated proteolysis of disc aggrecan within its interglobular domain (IGD). Cellular senescence was elevated two-fold in discs of smoke-exposed mice. Smoke exposure increased vertebral endplate porosity, which closely correlates with IDD in humans. CONCLUSIONS: These findings further support tobacco smoke as a contributor to spinal degeneration. Furthermore, the data provide a novel mechanistic insight, indicating that smoking-induced IDD is a result of both reduced PG synthesis and increased degradation of a key disc extracellular matrix protein, aggrecan. Cleavage of aggrecan IGD is extremely detrimental as this results in the loss of the entire glycosaminoglycan-attachment region of aggrecan, which is vital for attracting water necessary to counteract compressive forces. Our results suggest identification and inhibition of specific metalloproteinases responsible for smoke-induced aggrecanolysis as a potential therapeutic strategy to treat IDD.


Assuntos
Degeneração do Disco Intervertebral/induzido quimicamente , Osteoporose/induzido quimicamente , Fumar/efeitos adversos , Agrecanas/efeitos dos fármacos , Agrecanas/metabolismo , Animais , Senescência Celular/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoporose/diagnóstico por imagem , Osteoporose/metabolismo , Proteoglicanas/efeitos dos fármacos , Proteoglicanas/metabolismo , Proteólise/efeitos dos fármacos , Microtomografia por Raio-X
14.
Acta Neurol Scand ; 125(1): e3-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21413934

RESUMO

BACKGROUND: Obstructive sleep apnea (OSA) is prevalent in adults with epilepsy, especially refractory, but limited data exist in children with epilepsy. AIMS: We conducted a prospective pilot study in children with epilepsy to identify the prevalence of OSA and its relationship to the use of antiepileptic drugs (AEDs) and epilepsy types. METHODS: We used Michigan Pediatric Sleep Questionnaire (PSQ) in children with epilepsy. Patients were classified by seizures frequency as mild (0-1 seizure/month) or severe, refractory epilepsy (> 1 seizures/month). We used PSQ ≥ 0.33 as a cutoff point to assess the risk of OSA. RESULTS: Of 84 children, 52 were classified as mild and 32 as severe. Prevalence of OSA was significantly higher in the severe (43.8%) vs the mild group (30.7%, P < 0.05). Children on >1 AED had significantly higher prevalence of OSA (45.8%) than children on ≤1 AED (30.6%, P < 0.05). There was no significant correlation between the prevalence of OSA and seizure types. CONCLUSIONS: OSA is more prevalent in refractory epilepsy and in children who are on multiple AEDs. While further studies are needed to confirm these findings and to assess the consequences of OSA, we believe it is important to screen the children with epilepsy for OSA.


Assuntos
Epilepsia/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Adolescente , Anticonvulsivantes/uso terapêutico , Criança , Epilepsia/tratamento farmacológico , Epilepsia/etiologia , Feminino , Humanos , Masculino , Projetos Piloto , Prevalência , Estudos Prospectivos , Índice de Gravidade de Doença , Sono , Apneia Obstrutiva do Sono/etiologia , Inquéritos e Questionários
15.
Climacteric ; 15(2): 139-42, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22283418

RESUMO

Clinical trials usually use the relative risk (rate ratio or hazard ratio) to compare the effects of one treatment modality with others. However, the numbers needed to treat/harm (NNT/NNH) are sometimes used as another way of presenting an estimate of the effect of a medical intervention, pointing at the number of patients needed to be exposed over a certain period of time in order to achieve one beneficial or adverse event. For clinicians and patients, this is a very simple and clear tool to demonstrate the consequences of a specific intervention. Epidemiologists and statisticians are more cautious with interpretations of data of that sort. This article brings the relevant perspectives of a clinician, an epidemiologist and a statistician in regard to the value of NNT/NNH.


Assuntos
Epidemiologia , Números Necessários para Tratar , Estatística como Assunto , Humanos , Menopausa
16.
Int J Cosmet Sci ; 34(5): 416-23, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22712689

RESUMO

There is growing scientific evidence that the health, well-being and the attractiveness of the skin are strongly influenced by nutrition. Consumers recognize this and have supported the creation of a global cosmeceuticals market estimated in 2010 at $27.2 billion. Early in 2011, the US Department of Health and Human Services and Department of Agriculture issued the Dietary Guidelines for Americans, 2010. Twelve vitamins and nine minerals were recognized as essential. The minerals include calcium, copper, iron, magnesium, phosphorus, selenium, zinc, potassium and sodium. Although the topical benefits of several minerals such as zinc, magnesium and iron are recognized and, in some cases, approved by the FDA, the topical benefits of the others to the skin are largely unexplored and unexploited. This review attempts to summarize what has been published in the literature on the interactions of the eight of the nine essential elements with the skin.


Assuntos
Sais/farmacologia , Pele/efeitos dos fármacos , Pele/metabolismo , Humanos
17.
Curr Opin Cell Biol ; 10(5): 602-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9818170

RESUMO

Targeted mutagenesis has allowed investigators to perform controlled experiments in mammals and determine the contribution of individual proteins to physiologic and pathologic processes. Recent lessons learned from matrix metalloproteinase gene targeted mice and other in vivo observations have given new life to old concepts regarding the role of proteolytic fragments of extracellular matrix proteins in regulating a variety of critical processes in cell biology.


Assuntos
Matriz Extracelular/metabolismo , Metaloendopeptidases/metabolismo , Doenças Cardiovasculares/etiologia , Metaloendopeptidases/genética , Mutagênese Sítio-Dirigida , Neoplasias/etiologia , Penfigoide Bolhoso/etiologia , Enfisema Pulmonar/etiologia
18.
Nat Med ; 7(11): 1202-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11689884

RESUMO

Acute and fulminant liver failure induced by viral hepatitis, alcohol or other hepatotoxic drugs, are associated with tumor necrosis factor (TNF) production. In a mouse model of lethal hepatitis induced by TNF, apoptosis and necrosis of hepatocytes, but also lethality, hypothermia and influx of leukocytes into the liver, are prevented by a broad-spectrum matrix metalloproteinase (MMP) inhibitor, BB-94. Mice deficient in MMP-2, MMP-3 or MMP-9 had lower levels of apoptosis and necrosis of hepatocytes, and better survival. We found induction of MMP-9 activity and fibronectin degradation. Our findings suggest that several MMPs play a critical role in acute, fulminant hepatitis by degrading the extracellular matrix and allowing massive leukocyte influx in the liver. BB-94 also prevented lethality in TNF/interferon-gamma therapy in tumor-bearing mice. A broad-spectrum MMP inhibitor may be potentially useful for the treatment of patients with acute and perhaps chronic liver failure, and in cancer therapies using inflammatory cytokines.


Assuntos
Hepatite Animal/prevenção & controle , Inibidores de Metaloproteinases de Matriz , Fenilalanina/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Hepatite Animal/induzido quimicamente , Hepatite Animal/enzimologia , Hepatite Animal/patologia , Humanos , Interferon gama/uso terapêutico , Interferon gama/toxicidade , Metaloproteinases da Matriz/deficiência , Metaloproteinases da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/tratamento farmacológico , Fenilalanina/farmacologia , Inibidores de Proteases/farmacologia , Proteínas Recombinantes , Tiofenos/farmacologia , Fator de Necrose Tumoral alfa/uso terapêutico , Fator de Necrose Tumoral alfa/toxicidade
19.
Nat Med ; 4(5): 615-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9585238

RESUMO

Neutrophil elastase (NE) is a potent serine proteinase whose expression is limited to a narrow window during myeloid development. In neutrophils, NE is stored in azurophil granules along with other serine proteinases (cathepsin G, proteinase 3 and azurocidin) at concentrations exceeding 5 mM. As a result of its capacity to efficiently degrade extracellular matrix, NE has been implicated in a variety of destructive diseases. Indeed, while much interest has focused on the pathologic effects of this enzyme, little is known regarding its normal physiologic function(s). Because previous in vitro data have shown that NE exhibits antibacterial activity, we investigated the role of NE in host defense against bacteria. Generating strains of mice deficient in NE (NE-/-) by targeted mutagenesis, we show that NE-/- mice are more susceptible than their normal littermates to sepsis and death following intraperitoneal infection with Gram negative (Klebsiella pneumoniae and Escherichia coli) but not Gram positive (Staphylococcus aureus) bacteria. Our data indicate that neutrophils migrate normally to sites of infection in the absence of NE, but that NE is required for maximal intracellular killing of Gram negative bacteria by neutrophils.


Assuntos
Infecções por Enterobacteriaceae/imunologia , Elastase de Leucócito/deficiência , Neutrófilos/imunologia , Sepse/imunologia , Animais , Infecções por Enterobacteriaceae/mortalidade , Escherichia coli/patogenicidade , Injeções Intraperitoneais , Klebsiella pneumoniae/patogenicidade , Elastase de Leucócito/genética , Camundongos , Camundongos Mutantes , Neutrófilos/enzimologia , Sepse/mortalidade , Staphylococcus aureus/patogenicidade
20.
Nat Med ; 5(10): 1135-42, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10502816

RESUMO

Cardiac rupture is a fatal complication of acute myocardial infarction lacking treatment. Here, acute myocardial infarction resulted in rupture in wild-type mice and in mice lacking tissue-type plasminogen activator, urokinase receptor, matrix metalloproteinase stromelysin-1 or metalloelastase. Instead, deficiency of urokinase-type plasminogen activator (u-PA-/-) completely protected against rupture, whereas lack of gelatinase-B partially protected against rupture. However, u-PA-/- mice showed impaired scar formation and infarct revascularization, even after treatment with vascular endothelial growth factor, and died of cardiac failure due to depressed contractility, arrhythmias and ischemia. Temporary administration of PA inhibitor-1 or the matrix metalloproteinase-inhibitor TIMP-1 completely protected wild-type mice against rupture but did not abort infarct healing, thus constituting a new approach to prevent cardiac rupture after acute myocardial infarction.


Assuntos
Baixo Débito Cardíaco/etiologia , Ruptura Cardíaca/etiologia , Metaloendopeptidases/antagonistas & inibidores , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Inativadores de Plasminogênio/uso terapêutico , Inibidores de Proteases/uso terapêutico , Animais , Arritmias Cardíacas , Transplante de Medula Óssea , Movimento Celular , Colagenases/metabolismo , Técnicas de Transferência de Genes , Leucócitos/citologia , Leucócitos/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 9 da Matriz , Camundongos , Camundongos Mutantes , Neovascularização Fisiológica/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativadores de Plasminogênio/genética , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo
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