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1.
Clin Otolaryngol ; 41(3): 276-83, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26293165

RESUMO

OBJECTIVES: To determine the hearing status of survivors treated for head and neck rhabdomyosarcoma (HNRMS) at long-term follow-up. DESIGN: Cross-sectional long-term follow-up study. SETTING: Tertiary comprehensive cancer centre. PARTICIPANTS: Survivors treated for HNRMS during childhood in two concurrent cohorts; survivors in London had been treated with external beam radiotherapy (EBRT-based local therapy); survivors in Amsterdam were treated with AMORE (Ablative surgery, MOuld technique afterloading brachytherapy and surgical REconstruction) if feasible, otherwise EBRT (AMORE-based local therapy). MAIN OUTCOME MEASURES: We assessed hearing status of HNRMS survivors at long-term follow-up. Hearing thresholds were obtained by pure-tone audiometry. METHODS: We assessed the hearing thresholds, the number of patients with clinically relevant hearing loss and hearing impairment graded according to the Common Terminology Criteria for Adverse Events version 4.0 (CTCAEv4) and Boston criteria. Furthermore, we compared hearing loss between survivors treated with EBRT-based local therapy (London) and AMORE-based local therapy (Amsterdam). RESULTS: Seventy-three survivors were included (median follow-up 11 years). We found clinically relevant hearing loss at speech frequencies in 19% of survivors. Multivariable analysis showed that survivors treated with EBRT-based treatment and those with parameningeal tumours had significantly more hearing impairment, compared to survivors treated with AMORE-based treatment and non-parameningeal tumours. CONCLUSIONS: One in five survivors of HNRMS developed clinically relevant hearing loss. AMORE-based treatment resulted in less hearing loss compared to EBRT-based treatment. As hearing loss was highly prevalent and also occurred in survivors with orbital primaries, we recommend systematic audiological follow-up in all HNRMS survivors.


Assuntos
Neoplasias de Cabeça e Pescoço/terapia , Perda Auditiva/etiologia , Rabdomiossarcoma/terapia , Adolescente , Adulto , Audiometria de Tons Puros , Criança , Pré-Escolar , Estudos Transversais , Feminino , Seguimentos , Humanos , Lactente , Londres , Masculino , Países Baixos , Sobreviventes
2.
Osteoarthritis Cartilage ; 23(11): 2009-16, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26521747

RESUMO

Although a large proportion of patients with osteoarthritis (OA) show inflammation in their affected joints, the pathological role of inflammation in the development and progression of OA has yet to be clarified. Glutamate is considered an excitatory amino acid (EAA) neurotransmitter in the mammalian central nervous system (CNS). There are cellular membrane glutamate receptors and transporters for signal input modulation and termination as well as vesicular glutamate transporters (VGLUTs) for signal output through exocytotic release. Glutamate been shown to mediate intercellular communications in bone cells in a manner similar to synaptic transmission within the CNS. Glutamate-mediated events may also contribute to the pathogenesis and ongoing processes of peripheral nociceptive transduction and inflammation of experimental arthritis models as well as human arthritic conditions. This review will discuss the differential roles of glutamate signaling and blockade in peripheral neuronal and non-neuronal joint tissues, including bone remodeling systems and their potentials to impact OA-related inflammation and progression. This will serve to identify several potential targets to direct novel therapies for OA. Future studies will further elucidate the role of glutamate in the development and progression of OA, as well as its association with the clinical features of the disease.


Assuntos
Artrite Experimental/metabolismo , Aminoácidos Excitatórios/metabolismo , Ácido Glutâmico/metabolismo , Inflamação/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Nociceptividade/fisiologia , Osteoartrite/metabolismo , Animais , Artrite Experimental/fisiopatologia , Humanos , Inflamação/fisiopatologia , Osteoartrite/fisiopatologia , Transdução de Sinais/fisiologia , Transmissão Sináptica
3.
Diabet Med ; 32(11): 1460-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25970814

RESUMO

AIM: To compare the cardiovascular risks associated with second-line oral antidiabetic agents added to initial metformin therapy in a large nationwide observational study. METHODS: We conducted a nationwide retrospective cohort study using the Taiwan National Health Insurance database. A total of 36 118 users of different add-on oral antidiabetic agents (sulphonylureas, glinides, pioglitazone, α-glucosidase inhibitors and dipeptidyl peptidase-4 inhibitors) after initial metformin therapy were included in the analysis. The reference group was sulphonylureas added to metformin, the most commonly used combination regimen. The main outcomes of interest were hospitalizations for any cardiovascular event including acute myocardial infarction, congestive heart failure and ischaemic stroke. In the main analysis, all patients were followed within their initiation groups until the study end, disregarding any changes in treatment status over time. RESULTS: In intention-to-treat analyses, there was no difference in the risk of any cardiovascular event among the add-on combination treatment groups, but significantly lower risks of acute myocardial infarction were found for the glinides plus metformin treatment group (crude hazard ratio 0.52, adjusted hazard ratio 0.39; 95% CI 0.20-0.75) and for the α-glucosidase inhibitors plus metformin treatment group (crude hazard ratio 0.63, adjusted hazard ratio 0.54; 95% CI 0.31-0.95). No difference in risk of congestive heart failure or ischaemic stroke risk was found among the combination treatment groups. In secondary as-treated analyses, similar but less significant associations were found as compared with the primary intention-to-treat analyses for all treatment groups. CONCLUSION: There were no differences in overall cardiovascular risks among several add-on second-line oral antidiabetic agents; however, glinide plus metformin and α-glucosidase inhibitors plus metformin combination therapies might be associated with lower risks of acute myocardial infarction.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Administração Oral , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/epidemiologia , Quimioterapia Combinada , Registros Eletrônicos de Saúde , Feminino , Seguimentos , Inibidores de Glicosídeo Hidrolases/administração & dosagem , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Humanos , Hipoglicemiantes/administração & dosagem , Masculino , Metformina/administração & dosagem , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Programas Nacionais de Saúde , Estudos Retrospectivos , Risco , Taiwan/epidemiologia
5.
Osteoarthritis Cartilage ; 17(11): 1485-93, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19490963

RESUMO

OBJECTIVE: To study the effects of intra-articular injection of magnesium sulfate (MgSO(4)) on the development of osteoarthritis (OA) and to examine concomitant changes in the nociceptive behavior of rats. METHODS: OA was induced in Wistar rats with intra-articular injection of collagenase (500 U) in the right knee; the left knee was left untreated. In the OA+MgSO(4) group (n=7), the treated knee was injected with 500-microg (0.1-ml) MgSO(4) twice a week for 5 consecutive weeks starting at 1 week after collagenase injection; in the OA group (n=7), the same knee was injected with the same amount of physiological normal saline. In the MgSO(4) group (n=6), naïve rats received only MgSO(4) injections; in the control group (n=6), naïve rats received only physiological normal saline injections. Nociceptive behavior (mechanical allodynia and thermal hyperalgesia) on OA development was measured before and at 1, 2, 4, 6, and 8 weeks after collagenase injection, following which the animals were sacrificed. Gross morphology and histopathology were examined in the femoral condyles, tibial plateau, and synovia. Immunohistochemical analysis was performed to examine the effect of MgSO(4) on N-methyl-D-aspartate (NMDA) receptor subunit 1 phosphorylation (p-NR1) and apoptosis in the articular cartilage chondrocytes. RESULTS: OA rats receiving intra-articular MgSO(4) injections showed a significantly lower degree of cartilage degeneration than the rats receiving saline injections. MgSO(4) treatment also suppressed synovitis. Mechanical allodynia and thermal hyperalgesia showed significant improvement in the OA+MgSO(4) group as compared to the OA group. Moreover, MgSO(4) attenuated p-NR1 and chondrocyte apoptosis in OA-affected cartilage. CONCLUSIONS: Our results indicate that local intra-articular administration of MgSO(4) following collagenase injection in an experimental rat OA model (1) modulates chondrocyte metabolism through inhibition of cell NMDA receptor phosphorylation and apoptosis, (2) attenuates the development of OA, and (3) concomitantly reduces nociception.


Assuntos
Apoptose/efeitos dos fármacos , Artrite Experimental/patologia , Cartilagem Articular/patologia , Sulfato de Magnésio/farmacologia , N-Metilaspartato/farmacologia , Osteoartrite do Joelho/patologia , Animais , Artrite Experimental/tratamento farmacológico , Cartilagem Articular/efeitos dos fármacos , Injeções Intra-Articulares , Articulação do Joelho/patologia , Masculino , Osteoartrite do Joelho/tratamento farmacológico , Ratos , Ratos Wistar
6.
Br J Dermatol ; 158(3): 592-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18070211

RESUMO

BACKGROUND: Hand-foot skin reaction is a distinctive cutaneous side-effect of antineoplastic kinase inhibitor-targeted therapy. Severe hand-foot skin reaction requires postponement of treatment or dose reduction. Histopathological studies of skin toxicity associated with kinase inhibitors are currently unavailable. OBJECTIVES: To report the clinical and histopathological findings of hand-foot skin reaction produced by the multikinase inhibitor sorafenib. METHODS: Nine patients with metastatic carcinoma-seven with renal cell carcinoma (RCC), one with melanoma and one with hepatocellular carcinoma (HCC)-received continuous, oral sorafenib 400 mg twice daily. Hand-foot skin reaction was defined and graded according to National Cancer Institute Common Toxicity Criteria 3.0. Biopsies from lesions of erythematous scaly or blistering skin were obtained from five cases (four RCC and one HCC). RESULTS: Seven of the nine (78%) patients developed hand-foot skin reaction characterized by well-demarcated, tender, erythematous papules and plaques with greyish blisters or hyperkeratotic, callus-like formations on palmoplantar surfaces and distal phalanges. Skin biopsy of hand-foot skin reaction lesions revealed epidermal acanthosis, papillomatosis, parakeratosis, dispersed dyskeratotic cells and keratinocyte vacuolar degeneration. Other skin toxicities included angular cheilitis, seborrhoeic dermatitis and perianal dermatitis. CONCLUSIONS: The clinical manifestations and histopathological features of sorafenib-induced skin reactions are unique. The most relevant histopathological findings of hand-foot skin reaction include keratinocyte vacuolar degeneration, the presence of intracytoplasmic eosinophilic bodies, and intraepidermal blisters in the stratum malpighii. Further studies are warranted to elucidate the mechanisms of this novel multitargeted kinase inhibitor-associated skin reaction.


Assuntos
Benzenossulfonatos/efeitos adversos , Vesícula/induzido quimicamente , Toxidermias/etiologia , Dermatoses do Pé/induzido quimicamente , Dermatoses da Mão/induzido quimicamente , Inibidores de Proteínas Quinases/efeitos adversos , Piridinas/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Benzenossulfonatos/administração & dosagem , Vesícula/patologia , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/tratamento farmacológico , Toxidermias/patologia , Feminino , Dermatoses do Pé/patologia , Dermatoses da Mão/patologia , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Niacinamida/análogos & derivados , Compostos de Fenilureia , Inibidores de Proteínas Quinases/administração & dosagem , Piridinas/administração & dosagem , Sorafenibe , Resultado do Tratamento
7.
Anal Chem ; 78(8): 2640-5, 2006 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16615774

RESUMO

We have developed an UV/nano-TiO2 vapor generation (VG) device that when coupled between a chromatographic column and an ICP mass spectrometer provides a simple and sensitive hyphenated method for the determination of Se(IV) and Se(VI) without the need to use conventional chemical VG techniques. Because our proposed VG device allows both Se(IV) and Se(VI) species in the column effluent to be converted on-line into volatile Se products, which are then measured directly by the ICPMS, the safety risks and the probability of contamination arising from the use of additional chemicals are both low. To achieve the maximum signal intensity, we optimized a number of the operating parameters of the UV/nano-TiO2 VG device, including the acidity, the amounts of TiO2 and formic acid, and the length of the reaction coil, with respect to their effects on the reduction efficiency of the analyte species. This hyphenated method achieves excellent detection limits-0.06 and 0.03 ng mL(-1) for Se(IV) and Se(VI), respectively-because of the high efficiencies of the conversions of Se(IV) and Se(VI) to their respective volatile products and the lower blank level achieved, relative to those of other traditional systems. In addition, because the conversion efficiency of the analyte selenium species reached its maximum level within 36 s of irradiation, the working time (approximately 12 min) was limited primarily by time required for the chromatographic separation. A series of validation experiments-analysis of the 1643e Standard Reference Material and natural water samples-indicated that our proposed methods can be applied satisfactorily to the determination of inorganic selenium species in water samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Compostos de Selênio/análise , Selênio/análise , Titânio/química , Raios Ultravioleta , Cátions , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Água/análise , Água/química
8.
Nucl Med Commun ; 23(6): 569-72, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12029213

RESUMO

The aim of this study was to evaluate the possibility of pulmonary epithelial permeability damage in patients after hyperbaric oxygen therapy (HBOT) by 99mTc diethylenetriaminepentaacetic acid (99mTc-DTPA) aerosol inhalation lung scintigraphy. Twenty-five controls and 21 patients with normal chest X-rays and no cigarette smoking for at least 1 year were recruited for the study. 99mTc-DTPA aerosol inhalation lung scans were performed after 20 HBOT sessions in 21 patients with refractory osteomyelitis or diabetic foot. The HBOT with 100% oxygen at 2.5 atm absolute for 100 min was performed five times a week. Clearance rates (%/min) of 99mTc-DTPA aerosol in each lung field were calculated from the dynamic images for 30 min. Clearance rates of 99mTc-DTPA aerosol were compared between patients and controls by the unpaired t test. Thirteen patients who had 99mTc-DTPA aerosol lung scans before and after HBOT therapy studies were tested for statistical significance by using the paired t test. There was no statistically significant difference (P>0.05, unpaired t test) between patients and controls in every lung field. For the 13 patients who had 99mTc-DTPA aerosol studies both before and after 20 HBOT sessions, the results also showed no statistically significant difference (P>0.05, paired t test). It is concluded that there was no demonstrable pulmonary epithelial permeability change under current clinical HBOT protocol.


Assuntos
Oxigenoterapia Hiperbárica/efeitos adversos , Pneumopatias/diagnóstico por imagem , Pneumopatias/etiologia , Mucosa Respiratória/metabolismo , Pentetato de Tecnécio Tc 99m/farmacocinética , Administração por Inalação , Adulto , Aerossóis , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pneumopatias/metabolismo , Masculino , Pessoa de Meia-Idade , Permeabilidade , Estudos Prospectivos , Cintilografia/métodos , Compostos Radiofarmacêuticos/farmacocinética , Mucosa Respiratória/fisiopatologia , Pentetato de Tecnécio Tc 99m/administração & dosagem
9.
J Oral Pathol Med ; 30(8): 458-64, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11545236

RESUMO

Areca quid chewing has been linked to oral submucous fibrosis and oral cancer. Arecoline, a major areca nut alkaloid, is considered to be the most important etiologic factor in the areca nut. In order to elucidate the pathobiological effects of arecoline, cytotoxicity assays, cellular glutathione S-transferase (GST) activity and lipid peroxidation assay were employed to investigate cultured human buccal mucosal fibroblasts. To date, there is a large proportion of areca quid chewers who are also smokers. Furthermore, nicotine, the major product of cigarette smoking, was added to test how it modulated the cytotoxicity of arecoline. At a concentration higher than 50 microg/ml, arecoline was shown to be cytotoxic to human buccal fibroblasts in a dose-dependent manner by the alamar blue dye colorimetric assay (P<0.05). In addition, arecoline significantly decreased GST activity in a dose-dependent manner (P<0.05). At concentrations of 100 microg/ml and 400 microg/ml, arecoline reduced GST activity about 21% and 46%, respectively, during a 24 h incubation period. However, arecoline at any test dose did not increase lipid peroxidation in the present human buccal fibroblast test system. The addition of extracellular nicotine acted synergistically on the arecoline-induced cytotoxicity. Arecoline at a concentration of 50 microg/ml caused about 30% of cell death over the 24 h incubation period. However, 2.5 mM nicotine enhanced the cytotoxic response and caused about 50% of cell death on 50 microg/ml arecoline-induced cytotoxicity. Taken together, arecoline may render human buccal mucosal fibroblasts more vulnerable to other reactive agents in cigarettes via GST reduction. The compounds of tobacco products may act synergistically in the pathogenesis of oral mucosal lesions in areca quid chewers. The data presented here may partly explain why patients who combined the habits of areca quid chewing and cigarette smoking are at greater risk of contracting oral cancer.


Assuntos
Arecolina/efeitos adversos , Carcinógenos/efeitos adversos , Fibroblastos/efeitos dos fármacos , Mucosa Bucal/efeitos dos fármacos , Nicotina/efeitos adversos , Oxazinas , Xantenos , Análise de Variância , Areca/efeitos adversos , Bisbenzimidazol , Técnicas de Cultura de Células , Morte Celular/efeitos dos fármacos , Cocarcinogênese , Colorimetria , Corantes , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Inibidores Enzimáticos/efeitos adversos , Corantes Fluorescentes , Glutationa Transferase/antagonistas & inibidores , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Mucosa Bucal/citologia , Plantas Medicinais , Fatores de Risco , Fumar/efeitos adversos , Espectrometria de Fluorescência , Estatística como Assunto
10.
Clin Oral Investig ; 5(1): 51-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11355099

RESUMO

Betel nut chewing, like cigarette smoking, is a popular oral habit which impinges on the daily lives of a population of approximately 200 million. People who chew betel nuts have a higher prevalence of periodontal diseases than those who do not. Many of the undesirable effects of betel nuts have been attributed to arecoline, a major component of the particular alkaloid in betel nuts. In this in vitro study, we have focused on the effects of arecoline and the role it could play in periodontal breakdown via its direct effects on human gingival fibroblasts. Human gingival fibroblasts were derived from three healthy individuals undergoing crown-lengthening procedures. We found that arecoline is cytotoxic to human gingival fibroblasts at a concentration higher than 50 micrograms/ml by depleting intracellular thiols and inhibiting mitochondrial activity (P < 0.05). In addition, the cells displayed a marked arrest at G2/M phase in a dose-dependent manner. Repeated and long-term exposure to arecoline could impair the gingival fibroblast functions. As they are cytotoxic, the use of betel nut products in conjunction with periodontal therapy may interfere with optimal healing and/or lead to further periodontal breakdown.


Assuntos
Arecolina/toxicidade , Agonistas Colinérgicos/toxicidade , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Oxazinas , Xantenos , Adulto , Análise de Variância , Areca , Arecolina/administração & dosagem , Bisbenzimidazol , Células Cultivadas , Agonistas Colinérgicos/administração & dosagem , Cromatografia Líquida de Alta Pressão , Colorimetria , Corantes , Relação Dose-Resposta a Droga , Fibroblastos/citologia , Corantes Fluorescentes , Fase G2/efeitos dos fármacos , Gengiva/citologia , Glutationa/antagonistas & inibidores , Humanos , Mitocôndrias/efeitos dos fármacos , Mitose/efeitos dos fármacos , Plantas Medicinais , Estatística como Assunto , Compostos de Sulfidrila/antagonistas & inibidores
11.
J Clin Periodontol ; 28(3): 277-82, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11284543

RESUMO

BACKGROUND, AIMS: The habit of betel nut chewing impinges on the daily lives of approximately 200 million people. Betel quid chewers have a higher prevalence of periodontal diseases than non-chewers. This study examined the pathobiological effects of arecoline, a major component of the betel nut alkaloids, on human periodontal ligament fibroblasts (PDLF) in vitro. METHOD: Cell viability, proliferation, protein synthesis, and cellular thiol levels were used to investigate the effects of human PDLF exposed to arecoline levels of 0 to 200 microg/ml. In addition, nicotine was added to test how it modulated the effects of arecoline. RESULTS: Arecoline significantly inhibited cell proliferation in a dose-dependent manner. At concentrations of 10 and 30 microg/ml, arecoline suppressed the growth of PDLF by 20% and 50% (p < 0.05), respectively. Arecoline also decreased protein synthesis in a dose-dependent manner during a 24-h culture period. A 100 microg/ ml concentration level of arecoline significantly inhibited protein synthesis to only 50% of that in the untreated control (p < 0.05). Moreover, arecoline significantly depleted intracellular thiols in a dose-dependent manner. At concentrations of 25 microg/ml and 100 microg/ml, arecoline depleted about 18% and 56% of thiols (p < 0.05), respectively. This suggests that arecoline itself might augment the destruction of periodontium associated with betel nut use. Furthermore, the addition of nicotine acted with a synergistic effect on the arecoline-induced cytotoxicity. At a concentration of 60 microg/ml, arecoline suppressed the growth of PDLF by about 33% and 5 mM nicotine enhanced the arecoline-induced cytotoxic response to cause about 66% cell death. CONCLUSION: During thiol depletion, arecoline may render human PDLF more vulnerable to reactive agents within cigarettes. Taken together, people who combine habits of betel nut chewing with cigarette smoking could be more susceptible to periodontium damage than betel nut chewing alone.


Assuntos
Arecolina/efeitos adversos , Fibroblastos/efeitos dos fármacos , Nicotina/efeitos adversos , Ligamento Periodontal/efeitos dos fármacos , Areca/efeitos adversos , Arecolina/administração & dosagem , Morte Celular , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Corantes , Suscetibilidade a Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Sinergismo Farmacológico , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Nicotina/administração & dosagem , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , Plantas Medicinais , Biossíntese de Proteínas , Proteínas/efeitos dos fármacos , Estatística como Assunto , Compostos de Sulfidrila/análise , Sais de Tetrazólio , Tiazóis
12.
J Biomed Mater Res ; 56(1): 93-100, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11309795

RESUMO

SACCHACHITIN membrane, a weavable skin substitute made from the residual fruiting body of Ganoderma tsugae, has been demonstrated to promote skin wound healing. Prior to its clinical application, it is critical to learn more about any possible cytotoxicity, immunogenicity, or allergy response, and at least some of its mechanism(s) of action(s). In the present studies, it has been found that SACCHACHITIN suspension at less than 0.05% shows no cytotoxicity to the primary culture of rat fibroblasts. However, at higher concentrations (> or = 0.1%), it does reduce the growth of fibroblasts, based on MTT assays. This might be caused by positive charges on chitin molecules that are too strong, and may be harmful to the cell membrane. SACCHACHITIN showed no immunogenicity after it was inoculated into rats three times; however, the unmodified, purified rabbit type I and type II collagens did. Subcutaneous injection of SACCHACHITIN suspension into rats showed no gross allergic responses on skin. Nevertheless, it did cause local acute inflammation, as observed by histological investigation. This is similar to what occurred in the wound site covered with SACCHACHITIN membrane. The chemotactic effect of SACCHACHITIN was exhibited in both intact and wounded skin tissues. This may be one of the initial beneficial effects of SACCHACHITIN membrane to wound healing. The rapid acute inflammatory process was followed by the appearance of angiogenesis and granulation tissue formation, which occurred earlier than it normally would. Coverage of the wound area with SACCHACHITIN membrane also induced an earlier formation of scar tissue to replace the granulation tissue. A 1.5 x 1.5 cm(2) wound area covered by SACCHACHITIN completely healed by 21 days, while that covered with cotton gauze did not. Therefore, SACCHACHITIN is a safe biomaterial for use as a wound dressing for skin healing. Its promoting action for wound healing might be due to its chemotactic effect for inflammatory cells. This, in turn, may facilitate subsequent angiogenesis, granulation tissue formation, and faster new tissue formation, leading to faster wound healing.


Assuntos
Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/farmacologia , Pele Artificial/efeitos adversos , Cicatrização , Animais , Materiais Biocompatíveis , Curativos Biológicos/efeitos adversos , Células Cultivadas , Quimiotaxia , Dermatite/etiologia , Fibroblastos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Neovascularização Fisiológica , Ratos , Ratos Wistar , Reishi , Pele/irrigação sanguínea , Pele/imunologia , Pele/lesões
13.
Life Sci ; 67(17): 2103-15, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11057760

RESUMO

In present study the methylotrophic yeast, Pichia pastoris, was used to express a recombinant growth hormone (rGH) gene of swine. A synthetic secretion cassette was constructed using the promoter of the alcohol oxidase1 gene (AOX1), and a alpha-factor signal peptide. After electroporatic transformation and zeocin selection, several clones exhibited high levels of rGH protein expression constituting more than 20% of total yeast protein. Over 95% of rGH was shown to be export into the culture supernatant. Yeast transformant containing the highest recombinant growth hormone level (rGH yeast) and native GS115 Pichia pastoris (non-rGH yeast, as a control) were separately cultured, harvested and adsorbed by wheat bran. Yeast cultures of four dosages (0.05, 0.1, 0.2, and 0.4%) were mixed respectively with chick basal diet and fed to simulated country chickens for 9 weeks. The results showed that, when compared to control chicks, the percentage of body weight gain was improved significantly (P<0.05) in chicks fed with diets containing 0.1 or 0.2% rGH-rich yeast culture at brooding stage, and in chicks fed with 0.4% rGH-rich yeast culture at growing stage. The average weight gain in rGH yeast treated groups for the full-term (0 to 63d) and short term (43 to 63d) of growth were 10.6 and 9.4%, respectively, better than the non-rGH yeast control group. These experimental data suggest that the use of rGH-containing yeast as a supplement in fed provided an alternative approach for growth improvement in simulated country chickens.


Assuntos
Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Hormônio do Crescimento/genética , Pichia , Oxirredutases do Álcool/genética , Sequência de Aminoácidos , Ração Animal , Animais , Sequência de Bases , Clonagem Molecular , Hormônio do Crescimento/administração & dosagem , Fator de Acasalamento , Peptídeos/genética , Pichia/genética , Regiões Promotoras Genéticas , Sinais Direcionadores de Proteínas/genética , Proteínas Recombinantes/administração & dosagem , Suínos , Aumento de Peso
14.
J Nat Prod ; 63(6): 746-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10869192

RESUMO

Three new alkaloids, promucosine (1), romucosine F (2), and romucosine G (3), along with 28 known compounds, were isolated from the MeOH extract of stems of Annona purpurea. The structures of 1-3 were determined on the basis of spectral data and chemical evidence.


Assuntos
Alcaloides/isolamento & purificação , Plantas Medicinais/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Modelos Químicos , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
15.
Clin Oral Investig ; 3(1): 25-9, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10522189

RESUMO

Arecoline, a major betel nut alkaloid, has been detected in saliva obtained during betel nut chewing in concentrations up to 140 micrograms/ml, corresponding to 0.9 mM. Arecoline in the millimolar concentration range might participate in the initiation and/or progression of periodontal disease during the long-term effects of betel nut chewing. In this study, cell growth, cell proliferation, assessment of cytoplasmic enzyme lactate dehydrogenase (LDH) and collagen synthesis were used to investigate the effects of human gingival fibroblasts exposed to arecoline levels of 0-200 micrograms/ml. Control culture exhibited a normal monolayer of long spindle-shaped fibroblast morphology. Arecoline-treated human gingival fibroblasts showed a more rounded appearance and detached at the higher concentrations. At concentrations higher than 75 micrograms/ml, many cells had detached from the surface of the petri dish and numerous floating cells could be seen under the inverted microscope. At a concentrations higher than 25 micrograms/ml, arecoline inhibited cell growth, proliferation and collagen synthesis and increased LDH leakage in a dose-dependent manner (P < 0.05). These results indicate that arecoline is a cytotoxic agent to human gingival fibroblasts. Repeated and long-term exposure to arecoline could impair gingival fibroblast function. Betel quid chewers might be more susceptible to destruction of the periodontium and less responsive to a regeneration procedures during periodontal therapy.


Assuntos
Areca/efeitos adversos , Arecolina/toxicidade , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Extratos Vegetais/toxicidade , Plantas Medicinais , Análise de Variância , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/biossíntese , Fibroblastos/metabolismo , Gengiva/citologia , Humanos , L-Lactato Desidrogenase/análise
16.
J Oral Pathol Med ; 27(2): 68-71, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9526732

RESUMO

Betel quid chewing has been linked to oral submucous fibrosis and oral cancer. Cytotoxicity and genotoxicity assays were used to investigate the pathobiological effects of arecoline on cultured human buccal fibroblasts. Arecoline increased double-stranded polynucleic acid at the concentration of 0.1 to 10 micrograms/ml in a concentration-dependent manner. At a concentration higher than 50 micrograms/ml, arecoline was cytotoxic to cultured fibroblasts and the cytotoxicity was dose-dependent. No genotoxicity for arecoline was found even at a concentration of 400 micrograms/ml. On the other hand, 600 micrograms/ml glutathione (GSH) and 200 micrograms/ml glycyrrhizin could prevent the arecoline-induced cytotoxicity. These results indicate that arecoline is a cytotoxic agent and no genotoxicity was found to human buccal fibroblasts. Furthermore, increasing consumption of GSH- and glycyrrhizin-rich foods may reduce the oral diseases associated with betel quid chewing.


Assuntos
Arecolina/efeitos adversos , Citotoxinas/efeitos adversos , Fibroblastos/efeitos dos fármacos , Mucosa Bucal/efeitos dos fármacos , Mutagênicos/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacologia , Antídotos/farmacologia , Areca/efeitos adversos , Arecolina/administração & dosagem , Arecolina/antagonistas & inibidores , Células Cultivadas , Corantes , Citotoxinas/administração & dosagem , Citotoxinas/antagonistas & inibidores , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Comportamento Alimentar , Fibroblastos/citologia , Fluorescência , Glutationa/farmacologia , Ácido Glicirrízico/farmacologia , Humanos , Mastigação , Mucosa Bucal/citologia , Neoplasias Bucais/induzido quimicamente , Neoplasias Bucais/prevenção & controle , Mutagênicos/administração & dosagem , Fibrose Oral Submucosa/induzido quimicamente , Fibrose Oral Submucosa/prevenção & controle , Plantas Medicinais , Propídio , Compostos Radiofarmacêuticos , Timidina , Trítio
18.
J Formos Med Assoc ; 93(8): 709-14, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7858457

RESUMO

A 42-year-old female presented with progressive proximal muscle weakness, generalized hyperreflexia, marked bone pain, severe lumbago and knee arthralgia. Electromyographic study showed short-duration (5-10 msec), variable amplitude (200-2500 microV) polyphasic potentials. A muscle biopsy specimen revealed non-specific type II fiber atrophy. After a comprehensive laboratory work-up, adult Fanconi syndrome was diagnosed. The patient's symptoms, including bone pain and proximal muscle weakness, were relieved after a six-week supplement of tricalcium phosphate, vitamin D3 and sodium bicarbonate. The hyperreflexia also became less brisk.


Assuntos
Síndrome de Fanconi/complicações , Hipofosfatemia/etiologia , Doenças Musculares/etiologia , Osteomalacia/etiologia , Adulto , Feminino , Humanos , Atrofia Muscular/etiologia
20.
J Formos Med Assoc ; 90(1): 66-71, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1679112

RESUMO

We reviewed the myelograms and computed tomographic myelograms of 12 cases of intraspinal tumor with a "cupping sign" on the myelogram in the region of the conus medullaris from 1986 to 1988. There were 5 intramedullary tumors, 4 of them having an exophytic component, and 7 intradural-extramedullary tumors. The myelograms revealed that 4 of the 5 intramedullary tumors showed expansion and the outline of the conus medullaris was irregular, whereas 1 of the tumors showed smooth compression (crescent-shaped) and displacement of the conus medullaris. Six of the 7 intradural-extramedullary tumors showed smooth compression and displacement of the conus medullaris, while 1 of the tumors had caused expansion of the conus medullaris. Complete blockage of the passage of the contrast medium was noted in 3 of the 5 intramedullary tumors, while a partial block was noted in 3 of the 7 intradural-extramedullary tumors. Two of the 7 intradural-extramedulllary tumors showed an extradural tumor component, such as a dumb-bell tumor and a enlarged intervertebral neural foramen. Tumor calcification was noted in 1 of the 7 intradural-extramedullary tumors. Dural ectasia was noted in 2 of the 7 intradural-extramedullary tumors which were later proven to be neurofibromatosis. We conclude that smooth compression (crescent-shaped) and displacement of the conus medullaris, existence of an extradural tumor component, and eroded intervertebral neural foramina favor intradural-extramedullary tumors, while expansion and a conus medullaris with an irregular outline favors intramedullary tumors.


Assuntos
Neoplasias Meníngeas/diagnóstico por imagem , Mielografia , Neoplasias da Medula Espinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Astrocitoma/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurilemoma/diagnóstico por imagem , Estudos Retrospectivos
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