RESUMO
AIMS: It is well-known that chronic exposure to large amounts of ligand leads to downregulation of its receptor. It is not known, however, whether a GLP-1R agonist downregulates its receptor. For this reason, our study examined whether GLP-1R expression is reduced after long-term exposure to dulaglutide (Dula) in non-diabetic and diabetic mice. METHODS: Seven-week-old male db/db and db/m mice were given either Dula (0.6mg/kg×2/week) or a control vehicle (CTL) for 17 weeks. Various metabolic parameters, such as glucose-stimulated insulin secretion (GSIS), insulin and TG content in islets, were evaluated after the intervention. ß-cell-related gene expression was also analyzed by real-time RT-PCR. RESULTS: In db/m mice, GLP-1R expression in ß-cells did not decrease, not even after long-term administration of Dula, compared with control mice, while GLP-1R expression in 24-week-old db/db mice treated with Dula was augmented, rather than downregulated, compared with 24-week-old CTL db/db mice. This was probably due to improved glycaemic control. In db/db mice treated with Dula, food intake and blood glucose levels were significantly decreased up to 24 weeks of age compared with CTL db/db mice, and their expression levels of various ß-cell-related genes, insulin content and GSIS were also enhanced. In contrast, oxidative and endoplasmic reticulum stress, inflammation, fibrosis and apoptosis were suppressed with Dula treatment. CONCLUSION: Dula exerts beneficial effects on glycaemic control and has long-lasting protective effects on pancreatic ß-cells. GLP-1R expression levels were not reduced at all in non-diabetic as well as diabetic mice despite long-term dulaglutide exposure.
Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Peptídeos Semelhantes ao Glucagon/análogos & derivados , Fragmentos Fc das Imunoglobulinas/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Animais , Glicemia/metabolismo , Regulação para Baixo/efeitos dos fármacos , Peptídeos Semelhantes ao Glucagon/farmacologia , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , CamundongosRESUMO
BACKGROUND: Clinical studies of uterus transplantation have been performed to treat uterine factor infertility. Because the uterus is a pelvic visceral organ, the method of perfusion for the procurement of vital organs from a brain-dead donor should be modified for removal of the uterus. Herein, we report the results of a preliminary study in cynomolgus monkeys of a new perfusion method for uterus transplantation with assumed procurement of a uterus from a brain-dead donor. METHODS: Cynomolgus monkeys were used; thoracolaparotomy was performed on the donor. A perfusion catheter was then placed into the unilateral femoral artery and/or external iliac artery. Cross-clamping was performed for the aorta under the diaphragm and the inferior vena cava was divided in the pleural space. The perfusion solution was then administered via the catheter to perfuse all organs in the abdominal cavity, including those in the pelvic cavity. After the perfusion, gross observation and histopathological examination of abdominal organs were conducted. RESULTS: Gross findings showed that all abdominal organs turned white in all specimens, indicating favorable perfusion of the uterus and all other organs in the abdomen. Pathological findings showed that almost no hemocytes were observed in the vessels of each organ. CONCLUSIONS: With perfusion via the femoral artery and/or external iliac artery, all organs in the abdominal cavity, including the uterus, could be perfused. It was suggested that this technique could be useful for uterus transplantation assuming the procurement of a uterus from a brain-dead donor.
Assuntos
Preservação de Órgãos/métodos , Perfusão/métodos , Coleta de Tecidos e Órgãos/métodos , Útero/transplante , Animais , Morte Encefálica , Feminino , Macaca fascicularis , Doadores de Tecidos , Útero/irrigação sanguínea , Útero/patologiaRESUMO
In patients with severe hemorrhage, complications such as shock or death may occur if the patient is not treated appropriately and expeditiously. To create a hemostat kit for severe hemorrhage, ultraviolet light irradiation was applied to photocrosslinkable chitosan hydrogel and calcium alginate. As a hemorrhage model, the femoral arteries and veins of anesthetized rats were cut. Hemodynamics and hematological parameters including red blood cell (RBC) count, hemoglobin concentration, hematocrit, white blood cell (WBC) count, and platelet count, and serum parameters including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured as a marker of hemostasis. In rats for which no procedure was used, death occurred within 30 min. By using the hydrogel hemostat, the survival rate rose to 75% or more. RBC count, hemoglobin, hematocrit, and platelet levels were not significantly changed for 3 days. WBC count increased 1 day after hemostasis. AST and ALT increased 1 day after hemostasis, but it decreased 3 days later. The photocrosslinkable chitosan hydrogel and calcium alginate were biodegraded at 3 and 28 days, respectively, by neutrophils and keratinocyte chemoattractant.
Assuntos
Alginatos/administração & dosagem , Quitosana/administração & dosagem , Hemorragia/terapia , Hemostáticos/administração & dosagem , Alginatos/efeitos da radiação , Animais , Engenharia Biomédica , Contagem de Células Sanguíneas , Quitosana/efeitos da radiação , Reagentes de Ligações Cruzadas , Modelos Animais de Doenças , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/efeitos da radiação , Hematócrito , Hemodinâmica , Hemoglobinas/metabolismo , Hemorragia/sangue , Hemorragia/patologia , Hemorragia/fisiopatologia , Técnicas Hemostáticas , Hemostáticos/efeitos da radiação , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/efeitos da radiação , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/efeitos da radiação , Testes de Função Hepática , Masculino , Ratos , Ratos Sprague-Dawley , Raios UltravioletaRESUMO
BACKGROUND AND STUDY AIMS: Saline as an injection solution for endoscopic resection techniques has several disadvantages such as a short-lasting effect leading to a potentially higher risk of bleeding and perforation. The new substance of photocrosslinkable chitosan hydrogel in a DMEM/F12 medium (PCH) can be converted into an insoluble hydrogel by ultraviolet irradiation for 30 s, and was evaluated in two sets of animal experiments. METHODS: 18 pigs were used in the two parts of the study. First, mucosal resections were done with either PCH or hypertonic saline; the effects of both agents on wound healing were examined endoscopically and histologically. Second, in vivo degradation of PCH was examined using six pig stomachs. RESULT: PCH injection led to a longer-lasting elevation with clearer margins, compared with hypertonic saline, thus enabling precise endoscopic submucosal dissection (ESD) along the margins of the elevated mucosa. The endoscopic appearance after ESD was similar in both groups. PCH biodegradation was completed within 8 weeks according to endoscopic and histologic analyses. CONCLUSION: PCH is a promising agent for submucosal injection prior to various techniques of endoresection. It should be evaluated in clinical trials after biocompatibility testing for PCH is completed.
Assuntos
Materiais Biocompatíveis , Quitosana , Hidrogéis/administração & dosagem , Mucosa Intestinal/cirurgia , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/farmacocinética , Quitosana/farmacocinética , Reagentes de Ligações Cruzadas , Dissecação , Endoscopia , Estudos de Viabilidade , Hidrogéis/farmacocinética , Injeções , Masculino , Modelos Animais , Cloreto de Sódio/administração & dosagem , Suínos , Resultado do TratamentoRESUMO
OBJECTIVES: A large-scale postmarketing surveillance (PMS) study was carried out to determine the safety profile of infliximab in Japanese patients with rheumatoid arthritis (RA). METHODS: The PMS study was performed for all patients with RA who were treated with infliximab. They were consecutively registered in the PMS study at the initiation of infliximab treatment and were prospectively monitored with all adverse events noted for a period of 6 months. All case reports, which include safety-related events, were collected monthly. RESULTS: Adverse drug reactions (ADRs) were assessed for 6 months in 5000 patients who were consecutively enrolled in the PMS study. The incidence rates of total and serious ADRs were 28.0% and 6.2%, respectively. "Infections" or "respiratory disorders" were most commonly observed among serious ADRs. Bacterial pneumonia developed in 2.2%, tuberculosis in 0.3%, suspected Pneumocystis jiroveci pneumonia (PCP) in 0.4% and interstitial pneumonitis in 0.5%. Bacterial pneumonia (for which individuals of male gender, of older age and those with advanced rheumatoid arthritis and comorbid respiratory disease were most at risk) began to develop immediately after the start of treatment, while tuberculosis, PCP and interstitial pneumonitis developed about 1 month later. Serious infusion reactions were observed in 0.5% and were more likely to occur in patients who had participated in previous clinical trials of infliximab. CONCLUSION: This postmarketing surveillance study of patients treated with infliximab showed that infliximab in combination with low-dose MTX was well tolerated in Japanese patients with active RA.
Assuntos
Anticorpos Monoclonais/efeitos adversos , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Vigilância de Produtos Comercializados , Adulto , Idoso , Feminino , Humanos , Infliximab , Japão , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/etiologia , Vigilância de Produtos Comercializados/estatística & dados numéricos , Estudos Prospectivos , Medição de Risco , Resultado do Tratamento , Tuberculose Pulmonar/etiologiaRESUMO
BACKGROUND AND STUDY AIMS: We studied the ability of a photocrosslinkable chitosan in DMEM/F12 medium to maintain submucosal thickness and to reduce bleeding after mucosal resection. We also investigated the behavior of chitosan hydrogels with regard to wound healing. METHODS: The gastric submucosal layer of heparinized rats was injected with the photocrosslinkable chitosan in medium (which was then irradiated with ultraviolet light to form a hydrogel), or with sodium hyaluronate, or hypertonic saline, and three investigations were done, using three different sets of rats. The first and second were measurement of the thickness of the layer, and of the amount of bleeding induced by mucosal resection, respectively. Thirdly, the effects of the chitosan hydrogel on wound healing were examined histologically. RESULTS: Gastric submucosal layers of chitosan hydrogel-treated animals remained significantly thicker than those of other groups for at least 6 h after injection. The total amount of bleeding 20 min after mechanical mucosal resection was 170.0 +/- 20.0 mg, 678.3 +/- 226.3 mg, and 1020.0 +/- 104.1 mg in the chitosan hydrogel, sodium hyaluronate, and hypertonic saline groups, respectively. Histological study revealed that the focus of bleeding was surrounded by chitosan hydrogel and that almost all the hydrogel was biodegraded within 4 weeks. Furthermore, a discernible, but not statistically significant effect of the chitosan hydrogel on wound healing was observed. CONCLUSIONS: The chitosan hydrogel produced mucosal elevation after submucosal injection with ultraviolet irradiation, and it significantly reduced bleeding after mucosal resection. Our newly developed chitosan hydrogel in medium might be a promising submucosal agent for endoscopic mucosal resection.
Assuntos
Quitosana/administração & dosagem , Endoscopia Gastrointestinal/métodos , Mucosa Gástrica/patologia , Injeções/métodos , Animais , Endoscopia Gastrointestinal/efeitos adversos , Hemorragia Gastrointestinal/etiologia , Injeções/efeitos adversos , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
The cardiac arrhythmic suppression trial (CAST) reported that antiarrhythmic treatments in post-myocardial infarction (MI) patients resulted in poor outcome and decreased in heart rate variability indices (HRV). The goal of the present study was to determine whether aprindine and procainamide, antiarrhythmic agents that increase HRV, result in beneficial effects in post-MI rabbits. Four weeks before experiment, MI was induced in four rabbits by ligating the major branch of left coronary artery. A total of eight rabbits (four post-MI and four normal rabbits) were randomly assigned to treatment with either intravenous aprindine (1 mg/kg) or intravenous procainamide (15 mg/kg). Frequency domain HRV (low frequency spectra, LF, 0.04-0.15 Hz; high frequency spectra, HF, 0.15-0.40 Hz) were assessed by MemCalc software. Aprindine significantly increased HF and LF in both MI and normal rabbits, whereas procainamide tended to decrease HF and LF in MI and normal rabbits (in total rabbits; aprindine, LF, from 6.3 +/- 7.9 to 16.5 +/- 15.0 ms(2)/Hz, P < 0.05; HF, from 8.0 +/- 11.7 to 17.5 +/- 15.0 ms(2)/Hz, P < 0.05; procainamide, LF, from 4.9 +/- 7.4 to 4.8 +/- 8.5 ms(2)/Hz, NS; HF, from 11.1 +/- 23.0 to 5.1 +/- 10.6 ms(2)/Hz, NS). Under pharmacological denervation with propranolol (0.1 mg/kg) and atropine (0.04 mg/kg), aprindine increased LF and HF (LF, from 0.2 +/- 0.2 to 0.8 +/- 0.7 ms(2)/Hz, P < 0.05; HF, from 0.1 +/- 0.0 to 0.2 +/- 0.0 ms(2)/Hz, P < 0.05). These data suggest that aprindine can increase HRV in post-MI rabbits. Further experiments in human subjects would be of benefit.
Assuntos
Antiarrítmicos/farmacologia , Aprindina/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Frequência Cardíaca/efeitos dos fármacos , Infarto do Miocárdio/fisiopatologia , Procainamida/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Atropina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Denervação , Masculino , Infarto do Miocárdio/complicações , Propranolol/farmacologia , CoelhosRESUMO
Thyristors are a class of nonlinear electronic device that exhibit bistable resistance--that is, they can be switched between two different conductance states. Thyristors are widely used as inverters (direct to alternating current converters) and for the smooth control of power in a variety of applications such as motors and refrigerators. Materials and structures that exhibit nonlinear resistance of this sort are not only useful for practical applications: they also provide systems for exploring fundamental aspects of solid-state and statistical physics. Here we report the discovery of a giant nonlinear resistance effect in the conducting organic salt theta-(BEDT-TTF)2CsCo(SCN)4, the voltage-current characteristics of which are essentially the same as those of a conventional thyristor. This intrinsic organic thyristor works as an inverter, generating an alternating current when a static direct-current voltage is applied. Whereas conventional thyristors consist of a series of diodes (their nonlinearity comes from interface effects at the p-n junctions), the present salt exhibits giant nonlinear resistance as a bulk phenomenon. We attribute the origin of this effect to the current-induced melting of insulating charge-order domains, an intrinsically non-equilibrium phenomenon in the sense that ordered domains are melted by a steady flow.
RESUMO
Readily available from alpha-cyclodextrin in three steps, 2,3-anhydro-alpha-cyclomannin composed of six alpha-(1-->4)-linked 2,3-anhydro-D-mannopyranose residues, crystallizes well when precipitated from aqueous ethanol. An X-ray structure reveals the macrocycle to contain ethanol in its cavity, thus representing the first inclusion complex of a non-glucose cyclooligosaccharide. The wider rim of the torus-shaped macrocycle holds the six epoxide rings whose oxygens point away from the cavity, thereby sculpturing the unique over-all shape of a six-pointed star.
Assuntos
Compostos de Epóxi/química , Etanol/química , Oligossacarídeos/química , Piranos/química , Sequência de Carboidratos , Fenômenos Químicos , Físico-Química , Ligação de Hidrogênio , Lipídeos/química , Dados de Sequência Molecular , Difração de Raios XRESUMO
Secondary imidazole-appended beta-cyclodextrin 5 with a nondistorted cavity synthesized from a novel intermediate 3-amino-3-deoxy-beta-cyclodextrin exhibits much greater catalytic activity in the ester hydrolysis than its isomer 6 with a distorted cavity, indicating that the catalytic activities of secondary functional cyclodextrins are dependent on cavity structures.
Assuntos
Ciclodextrinas/metabolismo , Ciclodextrinas/farmacologia , beta-Ciclodextrinas , Catálise , Ciclodextrinas/química , Hidrólise , Cinética , Relação Estrutura-AtividadeRESUMO
To study the early stages of concrete corrosion by bacteria, sulfur-oxidizing bacterium strain RO-1, which grows in an alkaline thiosulfate medium (pH 10.0) was isolated from corroded concreate and characterized. Strain RO-1 was a Gram negative, rod-shaped bacterium (0.5-0.6×0.9-1.5 µm). The mean G+C content of the DNA of strain RO-1 was 65.0 mol%. Optimum pH and temperature for growth were 8.0. and 30-37°C, respectively. When grown in thiosulfate medium with pH 10.0, growth rate of the strain was 48% of that observed at the optimum pH for growth. Strain RO-1 used sulfide, thiosulfate, and glucose, but not elemental sulfur or tetrathionate, as a sole energy source. Strain RO-1 grew under anaerobic conditions in pepton-NO3 (-) medium containing sodium nitrate as an electron acceptor, and had enzyme activities that oxidized sulfide, elemental sulfur, thiosulfate, sulfite, and glucose, but not tetrathionate. The bacterium had an activity to assimilate (14)CO2 into the cells when thiosulfate was used as an energy source. These results suggest that strain RO-1 is Thiobacillus versutus. Strain RO-1 exuded Ca(2+) from concrete blocks added to thiosulfate medium with pH 9.0 and the pH of the medium decreased from 9.0 to 5.5 after 22 days of cultivation. In contrast, Thiobacillus thiooxidans strain NB1-3 could not exude Ca(2+) in the same thiosulfate medium, suggesting that strain RO-1, but not T. thiooxidans NB1-3, is involved in the early stage of concrete corrosion because concrete structures just after construction contain calcium hydroxide and have a pH of 12-13.
RESUMO
Oil mists at an automobile factory were measured size-selectively. Furthermore, subjective symptoms were surveyed through the distribution of a questionnaire. The measured levels of respirable-size, 2-10 micrometer oil mists at 3 selected workshops ranged 0.04-0.09 mg/m3 for the lower exposed group (17 men), 0.10-0.18 mg/m3 for the higher exposed group (16 men) to water-insoluble oil, and 0.08-0.29 mg/m3 for the higher exposed group (19 men) to water-soluble oil. The higher the level of exposure to respirable-size particulates, the more workers complained of dissatisfaction with air quality. As to the subjective symptoms, the "yes" rate for "irritated nose" and "sneezing" showed significant differences among the unexposed, lower exposed, and higher exposed groups. Workers using water-soluble oil complained of "uncomfortable smell" more than those who used water-insoluble oil. The results of this study suggested that it is necessary to measure the levels of oil mists size-selectively.
Assuntos
Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Óleos Industriais/efeitos adversos , Metalurgia , Exposição Ocupacional/efeitos adversos , Distribuição de Qui-Quadrado , Humanos , Masculino , Tamanho da Partícula , Inquéritos e QuestionáriosRESUMO
Although a form of eating disorders had been described by Kampo (Chinese traditional medicine) physicians during the last quarter of the 18th century, the modern study on eating disorders in Japan dates from the end of the 1950s. With the rapid increase in the number of cases, research activities have become very active recently. Both the past and present status of eating disorders and of research activities relating to them in Japan are not well known in other countries. This study concentrates on a review of the literature, with a focus on prevalence, etiology, and symptoms.
Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Humanos , Japão/epidemiologiaRESUMO
A 47-year-old male with pseudoaneurysm of the left ventricle secondary to mitral valve replacement was herein reported because of its unique etiology. The pseudoaneurysm was presumably resulted from the mitral valve dilator wound at the apex of the left ventricle, which was produced by closed mitral commissurotomy 23 years ago. To our knowledge, it seems to be a rare reported case with pseudoaneurysm of the left ventricle caused by closed transventricular mitral commissurotomy.
Assuntos
Falso Aneurisma/cirurgia , Cateterismo , Aneurisma Cardíaco/cirurgia , Próteses Valvulares Cardíacas , Estenose da Valva Mitral/terapia , Falso Aneurisma/etiologia , Aneurisma Cardíaco/etiologia , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgiaRESUMO
We report herein the case of a 22-year-old man with a history of Kawasaki disease who developed a giant calcified aneurysm of the left main coronary artery. The aneurysm was successfully resected and coronary bypass surgery was performed using the bilateral internal thoracic arteries. The resected aneurysm, the maximal diameter of which was 27 mm, showed heavy calcification of the inner layer and extended into the adjacent coronary arteries, producing a significant narrowing of the lumen of both the left main trunk (50%) and the anterior descending branch (50%). Extensive intimal calcification presumably prevented normal luminal development and produced a significant narrowing as the patient grew into adulthood. A cause for stenotic lesions developing in the coronary artery adjacent to a coronary aneurysm in adults with a history of Kawasaki disease is suggested here by the resected aneurysm seen in this patient. Thus, adult patients with giant coronary artery aneurysms and significant stenotic lesions of the coronary artery associated with Kawasaki disease may require aneurysmectomy in addition to bypass surgery.