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1.
J Urol ; 196(4): 1261-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27220897

RESUMO

PURPOSE: Positron emission tomography using ligands targeting prostate specific membrane antigen has recently been introduced. Positron emission tomography imaging with (68)Ga-PSMA-HBED-CC has been shown to detect metastatic prostate cancer lesions at a high rate. In this study we compare multiparametric magnetic resonance imaging and prostate specific membrane antigen positron emission tomography of the prostate with whole mount ex vivo prostate histopathology to determine the true sensitivity and specificity of these imaging modalities for detecting and locating tumor foci within the prostate. MATERIALS AND METHODS: In a prospective clinical trial setting 20 patients with localized prostate cancer and a planned radical prostatectomy were recruited. All patients underwent multiparametric magnetic resonance imaging and positron emission tomography before surgery, and whole mount histopathology slides were directly compared to the images. European Society of Urogenital Radiology guidelines for reporting magnetic resonance imaging were used as a template for regional units of analysis. The uropathologist and radiologists were blinded to individual components of the study, and the final correlation was performed by visual and deformable registration analysis. RESULTS: A total of 50 clinically significant lesions were identified from the whole mount histopathological analysis. Based on regional analysis the sensitivity, specificity, positive predictive value and negative predictive value for multiparametric magnetic resonance imaging were 44%, 94%, 81% and 76%, respectively. With prostate specific membrane antigen positron emission tomography the sensitivity, specificity, positive predictive value and negative predictive value were 49%, 95%, 85% and 88%, respectively. Prostate specific membrane antigen positron emission tomography yielded a higher specificity and positive predictive value. CONCLUSIONS: A significant proportion of cancers are potentially missed and underestimated by both imaging modalities. Prostate specific membrane antigen positron emission tomography may be used in addition to multiparametric magnetic resonance imaging to help improve local staging in those patients undergoing retropubic radical prostatectomy.


Assuntos
Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/metabolismo , Reprodutibilidade dos Testes
2.
J Biomech Eng ; 136(2): 021023, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24362893

RESUMO

The present study, through finite element simulations, shows the geometric effects of a bioinspired solid on pressure and impulse mitigation for an elastic, plastic, and viscoelastic material. Because of the bioinspired geometries, stress wave mitigation became apparent in a nonintuitive manner such that potential real-world applications in human protective gear designs are realizable. In nature, there are several toroidal designs that are employed for mitigating stress waves; examples include the hyoid bone on the back of a woodpecker's jaw that extends around the skull to its nose and a ram's horn. This study evaluates four different geometries with the same length and same initial cross-sectional diameter at the impact location in three-dimensional finite element analyses. The geometries in increasing complexity were the following: (1) a round cylinder, (2) a round cylinder that was tapered to a point, (3) a round cylinder that was spiraled in a two dimensional plane, and (4) a round cylinder that was tapered and spiraled in a two-dimensional plane. The results show that the tapered spiral geometry mitigated the greatest amount of pressure and impulse (approximately 98% mitigation) when compared to the cylinder regardless of material type (elastic, plastic, and viscoelastic) and regardless of input pressure signature. The specimen taper effectively mitigated the stress wave as a result of uniaxial deformational processes and an induced shear that arose from its geometry. Due to the decreasing cross-sectional area arising from the taper, the local uniaxial and shear stresses increased along the specimen length. The spiral induced even greater shear stresses that help mitigate the stress wave and also induced transverse displacements at the tip such that minimal wave reflections occurred. This phenomenon arose although only longitudinal waves were introduced as the initial boundary condition (BC). In nature, when shearing occurs within or between materials (friction), dissipation usually results helping the mitigation of the stress wave and is illustrated in this study with the taper and spiral geometries. The combined taper and spiral optimized stress wave mitigation in terms of the pressure and impulse; thus providing insight into the ram's horn design and woodpecker hyoid designs found in nature.


Assuntos
Transferência de Energia/fisiologia , Modelos Biológicos , Espalhamento de Radiação , Som , Vibração , Animais , Força Compressiva/fisiologia , Simulação por Computador , Módulo de Elasticidade/fisiologia , Humanos , Pressão , Resistência ao Cisalhamento/fisiologia , Estresse Mecânico , Resistência à Tração/fisiologia , Viscosidade
3.
J Mech Behav Biomed Mater ; 119: 104400, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33893020

RESUMO

In this study, ram impacts at 5.5 m/s are simulated through finite element analysis in order to study the mechanical response of the brain. A calibrated internal state variable inelastic constitutive model was implemented into the finite element code to capture the brain behavior. Also, constitutive models for the horns were calibrated to experimental data from dry and wet horn keratin at low and high strain rates. By investigating responses in the different keratin material states that occur in nature, the bounds of the ram brain response are quantified. An acceleration as high as 607 g's was observed, which is an order of magnitude higher than predicted brain injury threshold values. In the most extreme case, the maximum tensile pressure and maximum shear strains in the ram brain were 245 kPa and 0.28, respectively. Because the rams do not appear to sustain injury, these impacts could give insight to the threshold limits of mechanical loading that can be applied to the brain. Following this motivation, the brain injury metric values found in this research could serve as true injury metrics for human head impacts.


Assuntos
Lesões Encefálicas , Encéfalo , Aceleração , Animais , Fenômenos Biomecânicos , Análise de Elementos Finitos , Cabeça , Humanos , Masculino , Ovinos , Estresse Mecânico
4.
Water Sci Technol ; 62(5): 1003-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20818039

RESUMO

The seasonal performance of four differently configured constructed wetland systems was compared for the treatment efficiency of nonpoint source pollution. Dead plants in the constructed wetlands increased the nitrogen removal rate during winter by providing organic carbon, which is essential for the denitrification process. However, when the wetlands released phosphorus from the dead plants, the removal rate of phosphorus decreased. After seven growing seasons, plant coverage was nearly 100%, and the dissolved oxygen (DO) concentration was lowered to 1.3-5.4 mg/L. Open-water sections were then constructed inside the wetlands, which resulted in enhanced DO concentrations as well as improved treatment efficiency of nutrients and biochemical oxygen demand (BOD). Overall, performance of the constructed wetland was improved BOD, total nitrogen, and total phosphorus with the establishment of open water sections in the constructed wetland system.


Assuntos
Poluentes da Água/isolamento & purificação , Poluição da Água/prevenção & controle , Purificação da Água/métodos , Água/normas , Áreas Alagadas , Eliminação de Resíduos Líquidos , Microbiologia da Água , Abastecimento de Água
5.
Clin Exp Metastasis ; 37(4): 551-560, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32519046

RESUMO

Prospective evidence for the clinical role and efficacy of prostate specific membrane antigen (PSMA) positron emission tomography (PET)/magnetic resonance imaging (MRI) combining MRI characterization and localization of lesions with PET avidity in comparison to conventional imaging is limited. In a prospective clinical trial, we aimed to evaluate the diagnostic yield and therapeutic impact of PSMA PET/MRI in men with biochemical recurrence (BCR) following curative therapy. A single-centre, prospective clinical trial at the Princess Alexandra Hospital recruited 30 patients with BCR. Patients underwent PSMA PET/MRI and concurrent conventional CT chest, abdomen, pelvis and whole-body bone scan. Biopsy was performed when safety possible for histological correlation of identified lesions. Clinical efficacy and impact of PSMA PET findings were evaluated. 30 patients with BCR were recruited (median PSA 0.69 ng/ml). PSMA avid lesions were present in 21 patients (70%). 23 patients were previously treated with definitive surgery, 6 patients received external beam radiotherapy and 1 patient had low dose rate brachytherapy. A total of 8 of 9 lesions biopsied were positive (88.9% histological correlation). PSMA PET/MRI detected local recurrence (p = 0.005) and pelvic lesions (p = 0.06) more accurately than conventional imaging. PSMA PET/MRI may be useful in staging men with biochemical recurrence, especially when PSA is low. Our data demonstrates a high detection rate, especially for locally recurrent disease, and highlights the role of this modality when PSA is low. This modality has the potential to significantly improve prostate cancer detection and may have implications for earlier salvage treatment, avoidance of futile local therapy and change patient management to lead to improved outcomes.


Assuntos
Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico , Estudos Prospectivos , Próstata/patologia , Antígeno Prostático Específico/análise , Neoplasias da Próstata/terapia
6.
Transplant Proc ; 50(3): 902-904, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29555245

RESUMO

Renal cancers are some of the most common solid organ malignancies found during follow-up of patients who have undergone renal transplantation (RT). In this case report, we describe a life-threatening spontaneous hemorrhage of a rare subtype of renal cell carcinoma in the native kidney of a 27-year-old man, 4 years after RT. After fluid resuscitation and stabilization, the patient underwent emergent open radical nephrectomy with the final histopathology reporting T1bN0Mx mucinous tubular and spindle cell (MTSC) carcinoma. This case report highlights the need to consider an underlying malignancy in patients who presents with spontaneous hemorrhage of native kidneys after RT.


Assuntos
Carcinoma de Células Renais/imunologia , Hospedeiro Imunocomprometido , Neoplasias Renais/complicações , Neoplasias Renais/imunologia , Transplante de Rim , Adulto , Carcinoma/complicações , Carcinoma/imunologia , Carcinoma/patologia , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/patologia , Hemorragia/etiologia , Humanos , Neoplasias Renais/patologia , Transplante de Rim/efeitos adversos , Masculino , Nefrectomia/efeitos adversos
7.
Arch Oral Biol ; 89: 1-8, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29407634

RESUMO

OBJECTIVES: This paper studies A. probatocephalus teeth and investigates the mechanical properties and chemical composition of the enameloid and dentin. DESIGN: Nanoindentation tests with a max load of 1000 µN and X-ray Energy Dispersive Spectroscopy (EDS) were performed along the diameter of the polished sample. Microstructural analysis of the dentin tubules was performed from SEM images. RESULTS: From nanoindentation testing, the dentin of the sheepshead teeth has a nanoindentation hardness of 0.89 ±â€¯0.21 (mean ±â€¯S.D.) GPa and a reduced Young's modulus of 23.29 ±â€¯5.30 GPa. The enameloid of A. probatocephalus has a hardness of 4.36 ±â€¯0.44 GPa and a mean reduced Young's modulus of 98.14 ±â€¯6.91 GPa. Additionally, nanoindentation tests showed that the enameloid's hardness and modulus increased closer to the surface of the tooth. X-ray Energy Dispersive Spectroscopy (EDS) data further suggests that the gradient may be a result of the wt% fluoride within the enameloid, where an increase in fluoride results in an increase in reduced Young's modulus and hardness. CONCLUSION: The microstructural characterization of the number density and area of the dentin tubules were used to address the porosity effect in the dentin to achieve the experimentally validated microhardness. The mechanical properties of the sheepshead teeth were also compared with previous nanoindentation tests from other aquatic species. The sheepshead teeth exhibit a greater reduced Young's modulus and hardness compared to shark and piranha teeth.


Assuntos
Dentina/química , Dentina/ultraestrutura , Peixes/anatomia & histologia , Dente/química , Dente/ultraestrutura , Animais , Fenômenos Biomecânicos , Esmalte Dentário/química , Esmalte Dentário/diagnóstico por imagem , Esmalte Dentário/efeitos dos fármacos , Análise do Estresse Dentário , Dentina/diagnóstico por imagem , Dentina/efeitos dos fármacos , Módulo de Elasticidade , Fluoretos/farmacologia , Dureza , Estresse Mecânico , Dente/diagnóstico por imagem , Dente/efeitos dos fármacos
8.
Transplant Proc ; 50(8): 2350-2353, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316356

RESUMO

Kidney transplant recipients are at increased risk of cardiovascular morbidity and malignant neoplasm, and meticulous evaluation of potential recipients is needed to minimize risks of complications after transplantation. The purpose of this study was to analyze the results of preoperative assessments and document the importance of timed and detailed examinations. METHODS: Medical records of patients evaluated as kidney transplant candidates from January 2015 to September 2017 were retrospectively collected and analyzed. RESULTS: Of the 216 patients evaluated during the study period, 135 (62.5%) were male, 112 (51.9%) had diabetes mellitus, 163 (75.5%) had hypertension, 31 (14.4%) had a cardiovascular event history, and 7 (3.2%) had previous history of malignant neoplasms. Mean (SD) patient age was 50.7 (10.8) years. All 216 recipient candidates underwent echocardiography. Mean (SD) ejection fraction was 57.8% (5.9%), and 48 candidates (22.2%) showed regional wall motional abnormality. Coronary angiography was performed on 81 candidates, and in 57 (70.4%) of these, coronary artery disease was detected. Malignant neoplasms were detected in 10 (4.6%) candidates. Kidney transplantation was performed on 55 candidates. One recipient died of Pneumocystis jirovecii pneumonia at 15 months after kidney transplant, but there was no death-censored graft failure, newly detected malignant neoplasm, or cardiovascular event over a mean (SD) follow-up duration of 15.5 (8.6) months. CONCLUSION: Evaluation of kidney transplant candidates resulted in diagnoses of malignant neoplasms in 4.6% of patients and coronary artery disease in 26.4% of patients. The results of this study demonstrate candidates for kidney transplant should undergo detailed preoperative evaluation.


Assuntos
Transplante de Rim , Doadores Vivos , Adulto , Feminino , Humanos , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos , Fatores de Risco
9.
Transplant Proc ; 50(10): 3113-3120, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30577176

RESUMO

BACKGROUND: To analyze our initial results of hand-assisted laparoscopic living donor nephrectomy, executed by a skilled gastrointestinal surgeon. METHODS: A total of 22 consecutive patients underwent the hand-assisted laparoscopic living donor nephrectomy between December 2014 and January 2017. We retrospectively analyze the patient's perioperative clinical data, which were collected prospectively. RESULTS: The right kidney was harvested in 12 patients. The mean operative time and intraoperative blood loss was 241.0 ± 43.4 minutes (range, 140-310 min) and 293.2 ± 203.1 mL (range, 50-700 mL), respectively. The mean warm ischemic time was 288.4 ± 103.4 seconds (range, 179-610 s). Postoperative complications included chyle leakage in 2 patients who were left kidney donors and oliguria in 1 patient who was a right kidney donor. All patients recovered with conservative care, and the mean hospital stay was 7.5 ± 1.7 days. The mean creatinine level was 0.7 ± 0.2 mg/dL before surgery, 1.1 ± 0.3 mg/dL at postoperative day (POD) 1, and 1.0 ± 0.2 mg/dL after discharge. The mean glomerular filtration rate was 97.9 ± 18.2 mL/min/1.73 m2 before surgery, 60.7 ± 10.4 at POD 1, and 67.3 ± 11.1 after discharge. Operation time was not associated with patient body mass index and case number. No significant differences, other than postoperative complications, were found in the perioperative data for the side of kidney donation. CONCLUSION: A skilled surgeon with experience in laparoscopic abdominal surgery (such as gastrectomy or colectomy) might safely perform hand-assisted donor nephrectomy. However, we could not identify a clear case number to complete the learning curve.


Assuntos
Cirurgia Geral/educação , Laparoscopia Assistida com a Mão/educação , Transplante de Rim/educação , Nefrectomia/educação , Coleta de Tecidos e Órgãos/educação , Adulto , Perda Sanguínea Cirúrgica , Feminino , Taxa de Filtração Glomerular , Laparoscopia Assistida com a Mão/efeitos adversos , Laparoscopia Assistida com a Mão/métodos , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/métodos , Curva de Aprendizado , Tempo de Internação , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Nefrectomia/efeitos adversos , Nefrectomia/métodos , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Coleta de Tecidos e Órgãos/métodos , Isquemia Quente
10.
Cell Prolif ; 40(2): 268-81, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17472732

RESUMO

INTRODUCTION: The Epstein-Barr virus transforms resting B cells into proliferating lymphoblastoid cells, the origin of cell lines. METHOD AND RESULTS: Our cDNA microarray analyses led to the identification of 232 up-regulated and 112 down-regulated genes with more than a 3-fold difference in lymphoblastoid cell lines compared to resting B cells. The functional classification of these genes exhibited the distinct expression signature for cell proliferation, cell cycle and an immune response. Among them, we verified the differential expression of several oncogenes such as stathmin 1 (STMN1), RAB27A, RAB9A, BACH1 and BACH2 using quantitative real-time reverse transcriptase-polymerase chain reactions or Western blot analysis. Expression of STMN1 (which is involved in regulation of the microtubule filament system, cell growth and S-phase of cell cycle) was increased in lymphoblastoid cell line as well as in 7-day post-Epstein-Barr virus infection B cells, compared to resting B cells. CONCLUSION: Thus, this study suggests that Epstein-Barr virus infection induces STMN1 expression, which play a role in cell cycle progression and proliferation in the human B lymphocyte.


Assuntos
Linfócitos B/metabolismo , Linfócitos B/virologia , Regulação da Expressão Gênica , Herpesvirus Humano 4/fisiologia , Estatmina/genética , Estatmina/metabolismo , Ciclo Celular , Processos de Crescimento Celular , Linhagem Celular , Transformação Celular Viral , Regulação para Baixo , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4/genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes
11.
Leukemia ; 20(1): 122-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16281068

RESUMO

c-Myc is instrumental in the progression of Burkitt's lymphoma including HL-60 human leukemia cells. We tested fatty acids for their inhibitory effect on the DNA binding of c-Myc/Max dimeric proteins of human origin, prepared as recombinant proteins encompassing DNA binding (basic) and dimerization (HLHZip) domain, and found that those suppress proliferation and induce apoptosis of DMSO-differentiated HL-60 cells. The analyzed IC50 values of myristic acid, stearic acid, gamma-linolenic acid, linoleic acid, linolenic acid and arachidonic acid by EMSA were 97(+/-3), 2.2(+/-1.2), 55(+/-5), 32(+/-2), 62(+/-12), 22(+/-2)microM for DNA binding of recombinant c-Myc/Max, respectively. According to the results shown by XTT assay, their influence on proliferation was quite different from the rank order of IC50. Whereas the degree of influence of the unsaturated fatty acids on the proliferation of DMSO-differentiated HL-60 cells was similar, the influence of saturated fatty acids, stearic acid in particular, was very weak at same concentrations. In addition, we confirmed that these fatty acids have no influence on the expression of c-Myc in DMSO-differentiated HL-60 cells. Our experiments demonstrated that the inhibitors for the DNA binding of c-Myc/Max contribute to the downregulation of Myc-dependent proliferation and to the inducement of apoptosis, and serve as an exploration of potent new inhibitors.


Assuntos
Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/efeitos dos fármacos , DNA/efeitos dos fármacos , Ácidos Graxos/farmacologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Proteínas Proto-Oncogênicas c-myc/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Sítios de Ligação , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Dimerização , Dimetil Sulfóxido/farmacologia , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Recombinantes/efeitos dos fármacos , Proteínas Recombinantes/metabolismo
12.
Ned Tijdschr Geneeskd ; 151(2): 118-22, 2007 Jan 13.
Artigo em Holandês | MEDLINE | ID: mdl-17315488

RESUMO

The negative effects of sunlight include the more frequent or earlier development of skin cancer and degenerative changes in the skin, and the occurrence ofphotodermatoses. - However, sunlight also has a favourable effects; specifically, it may inhibit the development and progression of diseases of the bones, muscles and skin, ofvarious malignancies (carcinoma of the prostate, breast, colon and ovary, non-Hodgkin lymphoma), and may prevent certain autoimmune diseases, particularly multiple sclerosis. - This protective effect is ascribed to an increased synthesis of vitamin D, which is important for bone metabolism and is also able to regulate cell proliferation and differentiation, apoptosis, tumour invasion and angiogenesis. - The possible consequence of this new information is that public information regarding exposure to sunlight must continue to include a warning against excessive exposure to the sun, while at the same time stimulating regular although limited sunbathing.


Assuntos
Neoplasias Induzidas por Radiação/prevenção & controle , Luz Solar , Terapia Ultravioleta , Deficiência de Vitamina D/prevenção & controle , Vitamina D/biossíntese , Relação Dose-Resposta à Radiação , Humanos , Neoplasias Induzidas por Radiação/epidemiologia , Medição de Risco , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/prevenção & controle , Luz Solar/efeitos adversos
13.
Eur J Cancer ; 42(14): 2222-32, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16904314

RESUMO

Accumulating evidence for beneficial effects of sunlight on several types of cancer with a high mortality rate makes it necessary to reconsider the health recommendations on sun exposure, which are now mainly based on the increased risks for skin cancer. We reviewed all published studies concerning sun exposure and cancer, excluding skin cancer. All selected studies on prostate (3 ecologic, 3 case-control and 2 cohort), breast (4 ecologic, 1 case-control and 2 cohort) and ovary cancer (2 ecologic and 1 case-control) showed a significantly inverse correlation between sunlight and mortality or incidence. Two ecologic, 1 case-control and 2 prospective studies showed an inverse relation between sunlight and colon cancer mortality; 1 case-control study found no such association. Ecologic studies on non-Hodgkin lymphoma (NHL) mortality and sunlight gave conflicting results: early studies showing mostly positive and later studies showing mostly negative correlations. Three case-control studies and 1 cohort study found a significant inverse association between the incidence of NHL and sunlight. The question of how to apply these findings to (public) health recommendations is discussed.


Assuntos
Neoplasias/prevenção & controle , Luz Solar , Neoplasias da Mama/mortalidade , Neoplasias da Mama/prevenção & controle , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias do Colo/mortalidade , Neoplasias do Colo/prevenção & controle , Exposição Ambiental , Feminino , Educação em Saúde , Humanos , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/prevenção & controle , Masculino , Neoplasias/mortalidade , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/prevenção & controle , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/prevenção & controle
14.
Anim Reprod Sci ; 95(3-4): 273-82, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16600531

RESUMO

The present study was undertaken to examine the effect of plasmin on sperm viability and sperm-oocyte interaction during in vitro fertilization in the pig. Porcine sperm, which were washed in Dulbecco's PBS were re-suspended and incubated in fertilization medium (mTBM; modified Tris-buffered medium) containing 0, 0.1, 1.0, 10.0 or 100.0ng/mL of plasmin. Sperm viability was not affected by plasmin treatment. Addition of plasmin in doses ranging from 0.1 to 100.0ng/mL for 2, 4 or 6h to washed boar sperm resulted in enhancement of acrosome reaction (AR) compared with untreated cells. The concentration of 0.1ng/mL plasmin (95+/-18 sperm/oocyte) had no effect on sperm binding, whereas 1.0ng/mL (123+/-21 sperm/oocyte), 10.0ng/mL (124+/-16 sperm/oocyte) and 100.0ng/mL (124+/-15 sperm/oocyte) of plasmin increased sperm binding compared with the control (83+/-15 sperm/oocyte). The zona pellucida solubility (zona dissolution time) was less in medium with 1.0ng/mL (123+/-24s), 10.0ng/mL (99+/-15s) or 100.0ng/mL (95+/-19s) plasmin compared with control (176+/-27s). When pig oocytes and sperm were co-incubated in various concentrations of plasmin for 6h, the penetration rate was greater in medium with 1.0ng/mL plasmin (77.5+/-3.1%) compared with the control. However, there were no differences in the polyspermic rates and mean number of sperm (MNS)/oocyte between the groups treated with plasmin and control. These results suggest that plasmin might play a role in events related to fertilization.


Assuntos
Fertilização in vitro/veterinária , Fibrinolisina/administração & dosagem , Fibrinolíticos/administração & dosagem , Interações Espermatozoide-Óvulo/efeitos dos fármacos , Suínos , Reação Acrossômica/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura , Feminino , Masculino , Oócitos/fisiologia , Solubilidade , Espermatozoides/fisiologia , Zona Pelúcida/efeitos dos fármacos
15.
Ned Tijdschr Geneeskd ; 150(20): 1108-15, 2006 May 20.
Artigo em Holandês | MEDLINE | ID: mdl-16756222

RESUMO

The annual incidence of the three main forms of skin cancer has increased rapidly over the past few decades by 2.4% in men and 3.9% in women for basal-cell carcinoma, 3.9% in men and 3.1% in women for melanoma and 1.2% in men and 3.4% in women for squamous-cell carcinoma. The mortality rate has increased less rapidly. There has been an increase of 1.8% per year in rates of melanoma and a decrease of 1.9% in squamous cell carcinoma. The mortality rate for melanoma in younger people appears to have stabilized, however the death rate in older men continues to increase. Possible causes of the increase include excessive exposure to ultraviolet rays, immunosuppression and viruses. Early detection continues to offer the best chance of a cure. Screening older men for melanoma should be considered. Rising incidence and improved survival rates mean that there are likely to be more new patients with skin cancer in the future. Problems in balancing the availability of preventative and curative care may be offset by the timely planning of available manpower, by optimizing medical policy and by implementing new technological developments such as dermatoscopy.


Assuntos
Carcinoma de Células Escamosas/epidemiologia , Melanoma/epidemiologia , Neoplasias Cutâneas/epidemiologia , Fatores Etários , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/prevenção & controle , Feminino , Humanos , Masculino , Programas de Rastreamento , Melanoma/diagnóstico , Melanoma/etiologia , Melanoma/prevenção & controle , Fatores de Risco , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos
16.
Med Hypotheses ; 97: 34-37, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27876126

RESUMO

Since it was discovered that UV radiation was the main environmental cause of skin cancer, primary prevention programs have been started. These programs advise to avoid exposure to sunlight. However, the question arises whether sun-shunning behaviour might have an effect on general health. During the last decades new favourable associations between sunlight and disease have been discovered. There is growing observational and experimental evidence that regular exposure to sunlight contributes to the prevention of colon-, breast-, prostate cancer, non-Hodgkin lymphoma, multiple sclerosis, hypertension and diabetes. Initially, these beneficial effects were ascribed to vitamin D. Recently it became evident that immunomodulation, the formation of nitric oxide, melatonin, serotonin, and the effect of (sun)light on circadian clocks, are involved as well. In Europe (above 50 degrees north latitude), the risk of skin cancer (particularly melanoma) is mainly caused by an intermittent pattern of exposure, while regular exposure confers a relatively low risk. The available data on the negative and positive effects of sun exposure are discussed. Considering these data we hypothesize that regular sun exposure benefits health.


Assuntos
Saúde , Luz Solar , Raios Ultravioleta , Animais , Ritmo Circadiano , Exposição Ambiental , Europa (Continente) , Feminino , Humanos , Masculino , Melanoma/patologia , Melatonina/metabolismo , Camundongos , Transplante de Neoplasias , Óxido Nítrico/metabolismo , Fatores de Risco , Serotonina/metabolismo , Neoplasias Cutâneas/patologia , Vitamina D/biossíntese
17.
Oncogene ; 35(41): 5435-5445, 2016 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-27041572

RESUMO

Hepatitis B virus X protein (HBx) contributes to the development of hepatocellular carcinoma (HCC), probably by regulating activities of many host or viral proteins through protein-protein interactions. In this study, we identified poly(ADP-ribose) polymerase (PARP1), a crucial factor in DNA repair, as an HBx-interacting protein using a proteomics approach. Coimmunoprecipitation and proximity ligation assays confirmed the binding and colocalization of HBx and PARP1 in the nucleus. The carboxyl-terminus of HBx protein bound to the catalytic domain of PARP1, and this binding reduced the enzymatic activity of PARP1 in both in vitro and in vivo assays. HBx interrupted the binding of PARP1 to Sirt6, which catalyzes the mono-ADP-ribosylation required for DNA repair. Consistently, overexpression of HBx inhibited the clearance of γH2AX DNA repair foci generated under oxidative stress in Chang liver cells. Recruitment of the DNA repair complex to the site-specific double-strand breaks was inhibited in the presence of HBx, when measured by laser microirradiation assay and damage-specific chromatin immunoprecipitation assays. Consequently, HBx increased signs of DNA damage such as accumulation of 8-hydroxy-2'-deoxyguanosine and comet formation, which were reversed by overexpression of PARP1 and/or Sirt6. Finally, the interaction between PARP1 and Sirt6 was markedly lower in the livers of HBx-transgenic mice and specimens obtained from HCC patients to compare with the corresponding control. Our data suggest that the physical interaction of HBx and PARP1 accelerates DNA damage by inhibiting recruitment of the DNA repair complex to the damaged DNA sites, which may lead to the onset of hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Poli(ADP-Ribose) Polimerase-1/genética , Sirtuínas/genética , Transativadores/genética , Animais , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Dano ao DNA/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Histonas/genética , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Camundongos , Camundongos Transgênicos , Poli(ADP-Ribose) Polimerase-1/metabolismo , Sirtuínas/metabolismo , Transativadores/metabolismo , Proteínas Virais Reguladoras e Acessórias
18.
Biochim Biophys Acta ; 558(1): 108-12, 1979 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-227457

RESUMO

Antibodies against purified (Na+ + K+)ATPase from the rectal gland of Squalus acanthias, as well as against its catalytic subunit, inhibited ouabain binding by as much as 50%. However, antibodies against the glycoprotein subunit did not inhibit ouabain binding. These data suggest that binding of antibody against the catalytic subunit to the enzyme either covers the ouabain binding site or destroys its confirmation, while binding of antibody against the glycoprotein has no such effect.


Assuntos
Anticorpos , Ouabaína/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Sítios de Ligação de Anticorpos , Cação (Peixe) , Glicoproteínas/imunologia , Substâncias Macromoleculares , Ligação Proteica , Glândula de Sal/enzimologia , ATPase Trocadora de Sódio-Potássio/imunologia
19.
Mol Endocrinol ; 11(10): 1544-51, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9280069

RESUMO

Human PRL binds Zn2+, but the function of the binding is not known. We investigated the effect on PRL production in pituitary cells by obtaining clones of GH4C1 cells stably transfected with human H27A-PRL, a mutant that does not bind Zn2+. Unexpectedly, clones transfected with the mutant human PRL made little rat PRL. Untransfected GH4C1 cells made between 0.5 to 10 microg rat PRL/10(5) cells in 24 h. Clones transfected with vector alone (four of four), wild type human PRL (six of six), or with human K69A-PRL (two of two) made amounts of rat PRL in the same range. Clones transfected with human H27A-PRL (five of five) made 0.003-0.1 microg rat PRL/10(5) cells in 24 h, and the production of rat PRL mRNA was reduced. Human H27A-PRL was not efficiently secreted; 20-40% newly synthesized H27A-PRL was degraded by 60 min, and there was usually a delay in release of newly synthesized H27A-PRL. Reduction of rat PRL production is not mediated through the PRL receptor, because no sequences for the receptor in GH4C1 cells were detected by RT-PCR. Proteins involved in folding, such as BiP, were not specifically elevated in the H27A-PRL clones. In transient transfections, in which cells have not undergone selection, we found no evidence for disulfide-bonded aggregates of the mutant protein. The results indicate that Zn2+ binding stabilizes PRL in the secretory pathway; the instablility of the mutant protein may trigger effects that suppress rat PRL production directly or that indirectly result in selection of clones with low rat PRL production.


Assuntos
Hipófise/metabolismo , Prolactina/genética , Transdução de Sinais , Zinco/metabolismo , Animais , Linhagem Celular , Humanos , Mutação , Reação em Cadeia da Polimerase , Prolactina/metabolismo , Ligação Proteica , Ratos , Transfecção
20.
Arch Intern Med ; 149(8): 1802-4, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2764652

RESUMO

We studied 100 renal biopsy specimens from adults with the primary nephrotic syndrome in an inner city hospital serving mostly black patients and found that 47 had focal segmental glomerulosclerosis. Most of the men presented in the third decade of life, a peak distribution not seen in women. Half of the patients were hypertensive at presentation. Two thirds of the patients had not used intravenous drugs. The addicts were younger than nonaddicts (mean +/- SD age, 27 +/- 4 years vs 35 +/- 13 years), had greater proteinuria (10 +/- 5 g/d vs 6.3 +/- 5 g/d), and exhibited more glomerulosclerosis and tubulointerstitial fibrosis on biopsy. Of the 18 patients (8 addicts) remaining under our care, 4 addicts and 4 nonaddicts became uremic within 3 years. We conclude that even in the absence of drug addiction, focal segmental glomerulosclerosis is a common cause of primary glomerular disease in black adults, in whom it may represent a nonspecific glomerular reaction to injury. The prognosis in the nonaddict may not be different from that in the addict, but more patients need to be studied.


Assuntos
População Negra , Glomerulonefrite/patologia , Glomerulosclerose Segmentar e Focal/patologia , Nefrose/patologia , Transtornos Relacionados ao Uso de Substâncias/patologia , Adolescente , Adulto , Idoso , Feminino , Glomerulonefrite Membranoproliferativa/patologia , Humanos , Injeções Intravenosas , Nefrite Lúpica/patologia , Masculino , Pessoa de Meia-Idade
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