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1.
Dis Esophagus ; 29(3): 278-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25604848

RESUMO

Gastroesophageal reflux disease (GERD) is strongly associated with sleep disturbances. Although the mechanisms of this association have not been fully elucidated, nighttime reflux plays a central role. However, the detailed characteristics of nighttime reflux occurring during sleep are unknown. The aim of the present study was to examine the characteristics and prevalence of nighttime reflux in the natural sleep environment of GERD patients. Seventeen patients experiencing daily moderate-to-severe heartburn and/or regurgitation were studied using multichannel intraluminal impedance pH monitoring and electroencephalography off-proton pump inhibitor treatment. Nighttime reflux was divided based on reflux type (liquid or gas), acidity (acidic, weakly acidic, or alkaline) and extent (distal only or proximal migration) according to the standard criteria. Nighttime phases were divided as follows: recumbent-awake before falling asleep, nonrapid eye movement, rapid eye movement, awakening from sleep, and post-awakening in the morning. Among 184 nighttime refluxes, 43 (23%) occurred during recumbent-awake before falling asleep, 28 (15%) during nonrapid eye movement, 14 (8%) during rapid eye movement, 86 (46%) during awakening from sleep, and 13 (7%) during post-awakening in the morning. Liquid reflux was more common in awakening during sleep (92%), nonrapid eye movement (100%), and rapid eye movement (100%) compared with awakening before falling asleep (68%). The prevalence of proximal migration was significantly lower in nonrapid eye movement and rapid eye movement than in the other phases. There were no differences in acidity and bolus clearance time among the phases. Thirteen (65%) of 20 events with GERD symptoms had nighttime reflux, suggesting that only 7.1% (13 of 184) of nighttime refluxes were symptomatic. Nighttime reflux was observed in 48 (11%) of 425 awakening episodes during sleep. Different reflux patterns at each phase during nighttime might explain the pathogenesis of GERD and its related sleep disturbances.


Assuntos
Eletroencefalografia/métodos , Monitoramento do pH Esofágico/métodos , Refluxo Gastroesofágico/fisiopatologia , Transtornos do Sono-Vigília/diagnóstico , Sono/fisiologia , Adulto , Idoso , Ritmo Circadiano , Impedância Elétrica , Feminino , Refluxo Gastroesofágico/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Sono-Vigília/etiologia
2.
J Viral Hepat ; 21(5): 341-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24001168

RESUMO

We aimed to examine the relationship between renal dysfunction and anaemia that may develop during combination therapy involving pegylated interferon, ribavirin and telaprevir (PEG-IFN/RBV/TVR) for the treatment of chronic hepatitis C. Sixty-eight patients with genotype 1b high viral loads were treated with PEG-IFN/RBV/TVR. Peg-IFN and RBV doses were administered according to body weight. TVR was prescribed at 2250 mg/day for 44 patients and at 1500 mg/day for 24 patients who had low haemoglobin level (<12 g/dL). When anaemia had developed, the RBV dose was decreased. The serum TVR concentration at day 8 was measured, and the serum RBV concentration was measured serially. The estimated glomerular filtration rate (eGFR) was estimated to assess renal function. At week 1, serum TVR concentration was not correlated with a decrease in eGFR; however, the TVR dose, on a weight basis (mg/kg), and eGFR were correlated (r = 0.2691; P = 0.0265). Moreover, there was a negative correlation between eGFR and RBV serum concentration (r = −0.3694; P = 0.0025), and the serum RBV concentration and decrease in the haemoglobin were significantly correlated from week 1 to week 8. In triple therapy, the TVR dose per weight is correlated with a decline in renal function. Thus, the serum concentration of RBV increases, with a concomitant decrease in haemoglobin. It is important to adjust the doses of TVR and RBV to avoid excessive serum RBV levels and the development of severe anaemia, to achieve a good clinical effect.


Assuntos
Antivirais/efeitos adversos , Antivirais/farmacocinética , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/efeitos adversos , Insuficiência Renal/induzido quimicamente , Ribavirina/farmacocinética , Adulto , Idoso , Anemia/induzido quimicamente , Antivirais/uso terapêutico , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Feminino , Taxa de Filtração Glomerular , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Ribavirina/uso terapêutico , Soro/química
3.
J Musculoskelet Neuronal Interact ; 14(3): 325-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25198228

RESUMO

Heat stress could promote skeletal muscle regeneration. But, in the regeneration process, effects of heat stress on myogenic cells and the regulating factors is unknown. Therefore, Influences of heat stress soon after injury on distribution of the myogenic cells and chronological changes in expression of MyoD and myogenin were examined. The first peak of MyoD expression was temporally correlated with the time when proliferating satellite cells began to appear, and the rapid decline of the MyoD expression from the first peak, with the appearance time of myoblasts, respectively in both the non-Heat and Heat groups. The first peak of myogenin expression was temporally correlated with the time when multinuclear cells began to form in the both groups. Due to the heat stress, proliferation and differentiation of myogenic cells and chronological changes in these factors were accelerated one day earlier than in the non-Heat group. As MyoD and myogenin are regulating factor of proliferation and differentiation, heat stress soon after the muscle injury could accelerate the proliferation and differentiation of myogenic cells and the expression of their regulating factors MyoD and myogenin.


Assuntos
Transtornos de Estresse por Calor/metabolismo , Músculo Esquelético/lesões , Proteína MyoD/biossíntese , Miogenina/biossíntese , Regeneração , Animais , Diferenciação Celular , Transtornos de Estresse por Calor/complicações , Transtornos de Estresse por Calor/patologia , Masculino , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/patologia , Ratos , Células Satélites de Músculo Esquelético/metabolismo
4.
Endoscopy ; 44(6): 622-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22638783

RESUMO

This prospective study aimed to evaluate the feasibility and safety of locoregional mitomycin C (MMC) injection to treat refractory esophageal strictures after endoscopic submucosal dissection (ESD) for superficial esophageal carcinoma. Patients with dysphagia and strictures that were refractory to repeated endoscopic balloon dilation (EBD) were eligible. After EBD, MMC was injected into the dilated site. Between June 2009 and August 2010, five patients were recruited. The treatment was performed once in two patients and twice in three patients with recurrent dysphagia or restenosis. In all patients, passing a standard endoscope through the site was easy and the dysphagia grade improved (grade 3→1 in 3 patients, grade 4→2 in 2 patients). No serious complications were noted. During the observation period of 4.8 months, neither recurrent dysphagia nor re-stricture appeared in any of the patients. The combination of locoregional MMC injections and EBD is feasible and safe for the treatment of esophageal strictures after ESD.Recently, endoscopic submucosal dissection (ESD) has been developed and accepted as a new endoscopic treatment for gastrointestinal tumors. ESD is a promising treatment for superficial esophageal carcinoma (SEC), and it has a reliable en bloc resection rate. However, the application of ESD for widespread lesions is challenging because of the high risk of the development of severe strictures, which lead to a low quality of life after ESD. Although endoscopic balloon dilation (EBD) is effective for benign strictures, it needs to be performed frequently until the dysphagia disappears 1. Mitomycin C (MMC), which is a chemotherapeutic agent derived from some Streptomyces species 2, reduces scar formation when topically applied to a surgical lesion. MMC has been applied to treat strictures in a variety of anatomical locations, including a variety of organs 3. The aim of this study was to prospectively evaluate both the feasibility and the safety of locoregional MMC injection therapy in patients with refractory esophageal strictures after ESD for SEC.


Assuntos
Carcinoma/cirurgia , Transtornos de Deglutição/tratamento farmacológico , Neoplasias Esofágicas/cirurgia , Estenose Esofágica/tratamento farmacológico , Mitomicina/administração & dosagem , Idoso , Cateterismo , Transtornos de Deglutição/etiologia , Dissecação/efeitos adversos , Estenose Esofágica/etiologia , Esofagoscopia , Estudos de Viabilidade , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Mucosa/cirurgia , Estudos Prospectivos , Recidiva
5.
Clin Exp Immunol ; 163(2): 215-24, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21087446

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory bowel disease featuring infiltration by plasma cells producing immunoglobulins. We have reported previously the specific and significant proliferation of immature plasma cells in the inflamed colonic and pouch mucosa of UC patients. The aim of this study was to characterize peripheral blood immature plasma cells and the migration mechanisms of such immature plasma cells to inflamed sites in UC. The characteristics of peripheral blood immature plasma cells and chemokine receptor expression were examined by flow cytometry. Expression of mucosal chemokine was quantified using real-time reverse transcription-polymerase chain reaction and immunohistochemistry. The number of peripheral blood immature plasma cells was significantly higher in patients with active UC and active Crohn's disease (CD) than in healthy controls. The proportion of immature plasma cells was correlated positively with clinical activities of UC and CD. Many peripheral blood immature plasma cells were positive for CXCR3, CXCR4, CCR9 and CCR10. Expression of CXCR3 and CXCR4 in UC patients was significantly higher than in controls. CXCL9, CXCL10 and CXCL11 mRNA levels in colonic mucosa of inflamed IBD were higher than in controls. Immunofluorescence study also showed abundant CXCR3-positive immature plasma cells in the inflamed colonic mucosa of UC. Increased numbers of immature plasma cells may migrate towards inflammatory sites of UC via the CXCR3 axis, and may participate in UC pathogenesis.


Assuntos
Movimento Celular , Colite Ulcerativa/imunologia , Plasmócitos/imunologia , Receptores CXCR3/imunologia , Receptores CXCR4/imunologia , Adulto , Antígenos CD19/análise , Antígenos CD19/imunologia , Quimiocinas/análise , Quimiocinas/imunologia , Colite Ulcerativa/patologia , Doença de Crohn/imunologia , Doença de Crohn/patologia , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Contagem de Linfócitos , Pessoa de Meia-Idade , Receptores CCR/análise , Receptores CCR/imunologia , Receptores CCR/metabolismo , Receptores CXCR3/análise , Receptores CXCR4/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-19861508

RESUMO

The traditional Japanese medicine rikkunshito ameliorates the nitric oxide-associated delay in gastric emptying. Whether rikkunshito affects gastric motility associated with 5-hydroxytryptamine (serotonin: 5-HT) receptors or dopamine receptors is unknown. We examined the effects of rikkunshito on the delay in gastric emptying induced by 5-HT or dopamine using the phenol red method in male Wistar rats. 5-HT (0.01-1.0 mg kg(-1), i.p.) dose dependently delayed gastric emptying, similar to the effect of the 5-HT(3) receptor agonist 1-(3-chlorophenyl) biguanide (0.01-1.0 mg kg(-1), i.p.). Dopamine also dose dependently delayed gastric emptying. The 5-HT(3) receptor antagonist ondansetron (0.04-4.0 mg kg(-1)) and rikkunshito (125-500 mg kg(-1)) significantly suppressed the delay in gastric emptying caused by 5-HT or 1-(3-chlorophenyl) biguanide. Hesperidin (the most active ingredient in rikkunshito) suppressed the 5-HT-induced delayed gastric emptying in a dose-dependent manner, the maximum effect of which was similar to that of ondansetron (0.4 mg kg(-1)). The improvement obtained by rikkunshito or ondansetron in delaying gastric emptying was completely blocked by pretreatment with atropine. Rikkunshito appears to improve delay in gastric emptying via the antagonistic action of the 5-HT(3) receptor pathway.

7.
J Cell Biol ; 146(5): 1161-72, 1999 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-10477767

RESUMO

The multifunctional ADP-ribosyl cyclase, CD38, catalyzes the cyclization of NAD(+) to cyclic ADP-ribose (cADPr). The latter gates Ca(2+) release through microsomal membrane-resident ryanodine receptors (RyRs). We first cloned and sequenced full-length CD38 cDNA from a rabbit osteoclast cDNA library. The predicted amino acid sequence displayed 59, 59, and 50% similarity, respectively, to the mouse, rat, and human CD38. In situ RT-PCR revealed intense cytoplasmic staining of osteoclasts, confirming CD38 mRNA expression. Both confocal microscopy and Western blotting confirmed the plasma membrane localization of the CD38 protein. The ADP-ribosyl cyclase activity of osteoclastic CD38 was next demonstrated by its ability to cyclize the NAD(+) surrogate, NGD(+), to its fluorescent derivative cGDP-ribose. We then examined the effects of CD38 on osteoclast function. CD38 activation by an agonist antibody (A10) in the presence of substrate (NAD(+)) triggered a cytosolic Ca(2+) signal. Both ryanodine receptor modulators, ryanodine, and caffeine, markedly attenuated this cytosolic Ca(2+) change. Furthermore, the anti-CD38 agonist antibody expectedly inhibited bone resorption in the pit assay and elevated interleukin-6 (IL-6) secretion. IL-6, in turn, enhanced CD38 mRNA expression. Taken together, the results provide compelling evidence for a new role for CD38/ADP-ribosyl cyclase in the control of bone resorption, most likely exerted via cADPr.


Assuntos
Antígenos CD , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Reabsorção Óssea , NAD+ Nucleosidase/genética , NAD+ Nucleosidase/metabolismo , Osteoclastos/metabolismo , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Adenosina Difosfato Ribose/análogos & derivados , Adenosina Difosfato Ribose/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Antígenos de Diferenciação/química , Sequência de Bases , Sinalização do Cálcio , Membrana Celular/enzimologia , Células Cultivadas , Clonagem Molecular , ADP-Ribose Cíclica , Ativação Enzimática , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , Interleucina-6/farmacologia , Glicoproteínas de Membrana , Dados de Sequência Molecular , NAD/análogos & derivados , NAD/metabolismo , NAD+ Nucleosidase/química , Osteoclastos/citologia , Osteoclastos/enzimologia , RNA Mensageiro/análise , RNA Mensageiro/genética , Coelhos , Ratos , Ratos Wistar , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Homologia de Sequência de Aminoácidos
8.
Ann Hematol ; 88(8): 789-93, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19096845

RESUMO

Helicobacter pylori eradication is useful for improvement of a half of patients with idiopathic thrombocytopenic purpura (ITP), but its long-term therapeutic efficacy has not been elucidated. We investigated the long-term efficacy of H. pylori eradication in 30 cases with ITP that were included in our previous study regarding the association between H. pylori infection and ITP. Twenty-one cases were positive and nine cases were negative for H. pylori infection. H. pylori eradication therapy including secondary regimen was successful in 20 cases, half (responder) of whom showed ITP remission 1 month later. Nine responders could be followed up for a long time and did not show re-infection of H. pylori. Eight of nine needed no medication except for eradication therapy. Another case remained in remission for 1 year but thereafter needed a steroid therapy due to the recurrence. Eight nonresponders could be followed up for a long time. All these cases showed a bad clinical course even though they received the other post-treatments including steroid therapy. Three of nine H. pylori-negative cases underwent eradication therapy after obtaining the written informed consent, but none of them showed improvement. Of these three cases, two cases could be followed up. Only one case remained a remission although receiving corticosteroid as a post-treatment. Conditions of H. pylori-negative ITP cases were usually unstable for a long time. H. pylori eradication has a short-term efficacy for about half of H. pylori-positive ITP patients, and the responders to the eradication therapy may receive a long-term clinical benefit without other therapies.


Assuntos
Helicobacter pylori/efeitos dos fármacos , Púrpura Trombocitopênica Idiopática/virologia , 2-Piridinilmetilsulfinilbenzimidazóis , Corticosteroides/uso terapêutico , Adulto , Idoso , Amoxicilina , Claritromicina , Feminino , Seguimentos , Infecções por Helicobacter/tratamento farmacológico , Humanos , Lansoprazol , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Prospectivos , Indução de Remissão , Fatores de Tempo , Resultado do Tratamento
9.
Science ; 251(4989): 90-3, 1991 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-1702556

RESUMO

Members of the fibroblast growth factor (FGF) family of proteins stimulate the proliferation and differentiation of a variety of cell types through receptor-mediated pathways. The three-dimensional structures of two members of this family, bovine acidic FGF and human basic FGF, have been crystallographically determined. These structures contain 12 antiparallel beta strands organized into a folding pattern with approximate threefold internal symmetry. Topologically equivalent folds have been previously observed for soybean trypsin inhibitor and interleukins-1 beta and -1 alpha. The locations of sequences implicated in receptor and heparin binding by FGF are presented. These sites include beta-sheet strand 10, which is adjacent to the site of an extended sequence insertion in several oncogene proteins of the FGF family, and which shows sequence conservation among the FGF family and interleukin-1 beta.


Assuntos
Fator 1 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/química , Sequência de Aminoácidos , Animais , Bovinos , Fenômenos Químicos , Físico-Química , Cristalização , Fator 1 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Heparina/metabolismo , Humanos , Interleucina-1/química , Dados de Sequência Molecular , Estrutura Molecular , Conformação Proteica , Proteínas Recombinantes/química , Homologia de Sequência do Ácido Nucleico , Difração de Raios X
10.
Gut ; 57(5): 575-81, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18222984

RESUMO

BACKGROUND: Several studies have shown a strong association between reflux oesophagitis (RO) and bronchial asthma (BA). The precise mechanisms of interaction between RO and BA are uncertain, possibly due to lack of animal models. AIMS: We established a novel rat model and examined pathogenic interaction of RO and BA. METHODS: RO and BA were induced in Brown-Norway rats by ligating the transitional region between the forestomach and the glandular portion and wrapping the duodenum near the pylorus, and by ovalbumin (OVA) sensitisation and challenge with OVA aerosol. Rats were divided into four groups: control, RO, BA, and RO+BA. OVA-induced airway inflammation was assessed by the number of infiltrating cells and cytokine levels in bronchoalveolar lavage fluid (BALF). Oesophageal lesion index, histology and expression of cytokine mRNA, as determined by real-time RT-PCR, were also examined. RESULTS: Significant increases in the number of cells, especially eosinophils, and IL13 but not IFN-gamma concentration in BALF were observed in the RO+BA group compared with the BA group. These enhancements of OVA-induced airway inflammation were prevented by treatment with rabeprazole. Although the oesophagitis lesion index in the RO+BA group did not differ from that in the RO group, eosinophilic infiltration in the oesophageal submucosa and levels of mRNA expression of cytokines such as IL5, IL10, IL13, and RANTES were significantly increased. CONCLUSION: We established a novel rat model of RO and BA, and found significant interactions of the two diseases. This model thus appears to be useful for examining the association between gastro-oesophageal reflux disease and bronchial asthma.


Assuntos
Asma/complicações , Citocinas/metabolismo , Modelos Animais de Doenças , Eosinófilos/metabolismo , Esofagite Péptica/etiologia , Refluxo Gastroesofágico/etiologia , Animais , Asma/patologia , Lavagem Broncoalveolar/métodos , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Esofagite Péptica/patologia , Esôfago/citologia , Masculino , Inibidores da Bomba de Prótons/uso terapêutico , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Gut ; 57(2): 181-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17639086

RESUMO

BACKGROUND: Enterobacteria and cytokines both play roles in the pathophysiology of NSAID-induced enteropathy. Toll-like receptor (TLR) 4 recognises lipopolysaccharide (LPS), resulting in activation of an inflammatory cascade via the accessory protein MyD88. AIMS: To investigate role of TLR4 in inflammatory responses in indomethacin-induced enteropathy. METHODS: Indomethacin was administered p.o. to non-fasting rats and mice to induce small intestinal damage. The extent of such damage was evaluated by measuring the injured area stained dark blue with Evans blue. Rats were given antibiotics (ampicillin, aztreonam or vancomycin) p.o., or intraperitoneal LPS (a TLR4 ligand) or neutralising antibodies against neutrophils, tumour necrosis factor (TNF)-alpha, or monocyte chemotactic protein (MCP)-1. Furthermore, the intestinal ulcerogenicity of indomethacin was examined in TLR4-mutant, TLR4(-/-), and MyD88(-/-) mice. RESULTS: Indomethacin induced small intestinal damage with an increase in expression of TNF-alpha and MCP-1 in both rats and mice. Antibodies against neutrophils, TNF-alpha and MCP-1 inhibited the damage by 83%, 67% and 63%, respectively, in rats. Ampicillin and aztreonam also inhibited this damage, and decreased the number of Gram-negative bacteria in the small intestinal contents of the rat. However, vancomycin, which exhibited no activity against Gram-negative bacteria, had no preventive effect against this damage. Administration of LPS 1 h after indomethacin aggravated the damage, whereas LPS pretreatment inhibited it with reduction of expression of TLR4 and cytokines. In TLR4-mutant mice, the damage and cytokine expression were markedly inhibited. TLR4(-/-) and MyD88(-/-) mice were also resistant to the damage. CONCLUSIONS: Indomethacin may injure the small intestine through a TLR4/MyD88-dependent pathway.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Indometacina/efeitos adversos , Enteropatias/induzido quimicamente , Intestino Delgado/efeitos dos fármacos , Receptor 4 Toll-Like/fisiologia , Animais , Western Blotting , Lipopolissacarídeos/antagonistas & inibidores , Camundongos , Fator 88 de Diferenciação Mieloide/antagonistas & inibidores , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismo
12.
Rev Sci Instrum ; 90(8): 084707, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472660

RESUMO

We have constructed a cylindrical cavity resonator with a hybrid coupler where circularly polarized microwaves can be irradiated to a sample. The polarity of the microwave can be switched by changing the input ports of the hybrid coupler. The cavity resonator is small enough to be mounted on a cryostat which enables us to change the sample temperature in a wide range. To demonstrate the performance of the cavity resonator mounted on a cryostat, Yttrium Iron Garnet (YIG) was used as a test sample. We succeeded in selectively exciting left and right circularly polarized modes with high polarization (>80%). We also evaluated the susceptibility tensor of YIG in the cryostat. The technique presented here would offer a new direction in the fields of spintronics and quantum information.

13.
Curr Med Chem ; 15(21): 2086-98, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18781936

RESUMO

Alzheimer's disease (AD) is a complex disease, involving multiple factors such as the production of aggregation-prone amyloid beta (Abeta) peptides, the formation of fibrillarly tangles of microtubule-associating proteins, Tau, and the polymorphism of cholesterol binding protein, APOE4. While understanding the mechanism of AD and the involvement of key players should lead to rational drug discovery against this disease, a traditional screening approach should also work for identifying drugs using AD models. We have used a cellular AD model, in which a cell death was induced by AD-causing neurotoxicities, and then screened the genes, which rescued the cells from the cell death. This resulted in isolation of a gene encoding a novel 24-amino acid long peptide, termed Humanin (HN), which protected neuronal cells at approximately microM level. Surprisingly, these gene products and the synthetic peptides not only protected neurons from cell death induced by Abeta-related neurotoxicities, but also Abeta-unrelated neurotoxicities. While a broad range of activities of HN against AD-related insults is discovered, the detailed mechanism of its action is still obscure. Structure analysis of HN showed that it is largely disordered and flexible at low peptide concentrations and heavily aggregates at high concentrations. Interestingly, one of the HN analogs, which is 10000-times more active than the parent HN molecule (i.e. active below nM range), was found to be monomeric. Based on findings of structural analyses, we propose here that membrane environment may enable HN to achieve high affinity for target protein(s) with multiple-transmembrane domains, such as G-protein coupled receptors.


Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos e Proteínas de Sinalização Intracelular , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/patologia , Animais , Sítios de Ligação , Morte Celular/efeitos dos fármacos , Desenho de Fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Ligantes , Neurônios/patologia , Fármacos Neuroprotetores/química , Conformação Proteica , Relação Estrutura-Atividade
14.
J Viral Hepat ; 15(9): 651-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18637076

RESUMO

Serum ribavirin concentration is an important factor in antiviral therapy in combination with peginterferon (PEG-IFN) and ribavirin for patients with chronic hepatitis C in terms of both beneficial and adverse effects. We evaluated whether the serum ribavirin concentration can be predicted on the basis of renal function estimates. Serum creatinine and cystatin C concentrations were measured at the start of treatment in a total of 148 patients with chronic hepatitis C who underwent combination PEG-IFN and ribavirin therapy. Creatinine clearance (CrCl) and total clearance of ribavirin (CL/F) were calculated on the basis of the serum creatinine level. The glomerular filtration rate was calculated with two different formulae on the basis of the serum cystatin C level. These values were compared with serum ribavirin concentrations 4 weeks after the start of therapy. The cystatin C level increased with the progression of liver fibrosis, whereas the creatinine level was constant regardless of the degree of liver fibrosis. Significant correlation was not observed between the serum ribavirin concentration and serum creatinine level, cystatin C level, or calculated renal function estimates. However, significant correlation was found between the serum ribavirin concentration and CrCl and CL/F in patients who were given ribavirin >800 mg/day. Overall, renal function estimates do not correlate with the serum ribavirin concentration in Japanese patients with chronic hepatitis C who undergo combination PEG-IFN and ribavirin therapy. Serum creatinine-based renal function estimates might be predictive for the serum ribavirin concentration only in patients with a daily ribavirin intake of 800 mg or more.


Assuntos
Antivirais/farmacocinética , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Testes de Função Renal , Ribavirina/farmacocinética , Ribavirina/uso terapêutico , Idoso , Povo Asiático , Creatinina/sangue , Cistatina C , Cistatinas/sangue , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Polietilenoglicóis , Proteínas Recombinantes , Soro/química , Estatística como Assunto
15.
Neurogastroenterol Motil ; 30(7): e13319, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29498457

RESUMO

BACKGROUND: Functional dyspepsia (FD), a heterogeneous disorder, involves multiple pathogenetic mechanisms. Developing treatments for FD has been challenging. We performed a randomized, placebo-controlled, double-blind clinical trial to determine the efficacy of rikkunshito, a Japanese herbal medicine, in FD patients. METHODS: FD patients (n = 192) who met the Rome III criteria without Helicobacter pylori infection, predominant heartburn, and depression were enrolled at 56 hospitals in Japan. After 2 weeks of single-blind placebo treatment, 128 patients with continuous symptoms were randomly assigned to 8 weeks of rikkunshito (n = 64) or placebo (n = 61). The primary efficacy endpoint was global assessment of overall treatment efficacy (OTE). The secondary efficacy endpoints were improvements in upper gastrointestinal symptoms evaluated by the Patient Assessment of Upper Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM), the Global Overall Symptom scale (GOS), and the modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease (m-FSSG), and psychological symptoms evaluated by the Hospital Anxiety and Depression Scale (HADS). KEY RESULTS: Rikkunshito increased OTE compared to placebo at 8 weeks (P = .019). Rikkunshito improved upper gastrointestinal symptoms (PAGI-SYM, GOS, and m-FSSG) at 8 weeks, especially postprandial fullness/early satiety (P = .015 and P = .001) and bloating (P = .007 and P = .002) of the PAGI-SYM subscales at 4 weeks and 8 weeks. Improvement of HADS at 8 weeks (P = .027) correlated with those of PAGI-SYM (r = .302, P = .001), GOS (r = .186, P = .044), and m-FSSG (r = .462, P < .001), postprandial fullness/early satiety (r = .226, P = .014), dyspepsia (r = .215, P = .019), and PDS (r = .221, P = .016). CONCLUSION & INFERENCES: Rikkunshito may be beneficial for FD patients to simultaneously treat gastrointestinal and psychological symptoms.


Assuntos
Ansiedade/diagnóstico , Ansiedade/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Dispepsia/diagnóstico , Dispepsia/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/epidemiologia , Método Duplo-Cego , Dispepsia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
16.
Amino Acids ; 33(4): 587-605, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17357829

RESUMO

Amino acids are widely used in biotechnology applications. Since amino acids are natural compounds, they can be safely used in pharmaceutical applications, e.g., as a solvent additive for protein purification and as an excipient for protein formulations. At high concentrations, certain amino acids are found to raise intra-cellular osmotic pressure and adjust to the high salt concentrations of the surrounding medium. They are called "compatible solutes", since they do not affect macromolecular function. Not only are they needed to increase the osmotic pressure, they are known to increase the stability of the proteins. Sucrose, glycerol and certain amino acids were used to enhance the stability of unstable proteins after isolation from natural environments. The mechanism of the action of these protein-stabilizing amino acids is relatively well understood. On the contrary, arginine was accidentally discovered as a useful reagent for assisting in the refolding of recombinant proteins. This effect of arginine was ascribed to its ability to suppress aggregation of the proteins during refolding, thereby increasing refolding efficiency. By the same mechanism, arginine now finds much wider applications than previously anticipated in the research and development of proteins, in particular in pharmaceutical applications. For example, arginine solubilizes proteins from loose inclusion bodies, resulting in efficient production of active proteins. Arginine suppresses protein-protein interactions in solution and also non-specific adsorption to gel permeation chromatography columns. Arginine facilitates elution of bound proteins from various column resins, including Protein-A or dye affinity columns and hydrophobic interaction columns. This review covers various biotechnology applications of amino acids, in particular arginine.


Assuntos
Aminoácidos , Arginina , Biotecnologia , Proteínas/química , Proteínas/isolamento & purificação , Aminoácidos/química , Química Farmacêutica , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Desnaturação Proteica , Dobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Solubilidade , Temperatura
17.
Mol Cell Biol ; 18(10): 6063-74, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9742123

RESUMO

The fibroblast growth factors (FGFs) play key roles in controlling tissue growth, morphogenesis, and repair in animals. We have cloned a novel member of the FGF family, designated FGF-18, that is expressed primarily in the lungs and kidneys and at lower levels in the heart, testes, spleen, skeletal muscle, and brain. Sequence comparison indicates that FGF-18 is highly conserved between humans and mice and is most homologous to FGF-8 among the FGF family members. FGF-18 has a typical signal sequence and was glycosylated and secreted when it was transfected into 293-EBNA cells. Recombinant murine FGF-18 protein (rMuFGF-18) stimulated proliferation in the fibroblast cell line NIH 3T3 in vitro in a heparan sulfate-dependent manner. To examine its biological activity in vivo, rMuFGF-18 was injected into normal mice and ectopically overexpressed in transgenic mice by using a liver-specific promoter. Injection of rMuFGF-18 induced proliferation in a wide variety of tissues, including tissues of both epithelial and mesenchymal origin. The two tissues which appeared to be the primary targets of FGF-18 were the liver and small intestine, both of which exhibited histologic evidence of proliferation and showed significant gains in organ weight following 7 (sometimes 3) days of FGF-18 treatment. Transgenic mice that overexpressed FGF-18 in the liver also exhibited an increase in liver weight and hepatocellular proliferation. These results suggest that FGF-18 is a pleiotropic growth factor that stimulates proliferation in a number of tissues, most notably the liver and small intestine.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Intestino Delgado/citologia , Fígado/citologia , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Divisão Celular , Linhagem Celular Transformada , Células Cultivadas , Clonagem Molecular , DNA Complementar , Escherichia coli , Fatores de Crescimento de Fibroblastos/genética , Expressão Gênica , Humanos , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Tamanho do Órgão , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
18.
J Pharm Sci ; 96(12): 3214-25, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17721976

RESUMO

In the biotechnology area, the issue of comparability with an innovator product is complex. Ideally, a side-by-side comparison of physical properties would be part of the demonstration of comparability. However, biogeneric companies do not have access to the bulk drug substance from the innovator company for biophysical comparison, and isolation of protein from marketed product cannot be guaranteed to produce material that is identical to the bulk drug substance from which it was prepared. In a recently published study, protein was isolated from marketed product and comparative studies performed. In a follow-up investigation of the published work, we demonstrate here that even a simple isolation procedure can significantly compromise the protein, which raises serious questions about the interpretation of that study, and in a broader context the value of any studies done with such "out-of-process" protein.


Assuntos
Artefatos , Eritropoetina/química , Hematínicos/química , Tecnologia Farmacêutica/métodos , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Contaminação de Medicamentos , Estabilidade de Medicamentos , Epoetina alfa , Eritropoetina/isolamento & purificação , Hematínicos/isolamento & purificação , Concentração de Íons de Hidrogênio , Desnaturação Proteica , Controle de Qualidade , Proteínas Recombinantes , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta , Tecnologia Farmacêutica/normas , Ultracentrifugação
19.
Nat Biotechnol ; 16(3): 292-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9528012

RESUMO

Transgenic potatoes were engineered to synthesize a cholera toxin B subunit (CTB) pentamer with affinity for GMI-ganglioside. Both serum and intestinal CTB-specific antibodies were induced in orally immunized mice. Mucosal antibody titers declined gradually after the last immunization but were restored following an oral booster of transgenic potato. The cytopathic effect of cholera holotoxin (CT) on Vero cells was neutralized by serum from mice immunized with transgenic potato tissues. Following intraileal injection with CT, the plant-immunized mice showed up to a 60% reduction in diarrheal fluid accumulation in the small intestine. Protection against CT was based on inhibition of enterotoxin binding to the cell-surface receptor GMI-ganglioside. These results demonstrate the ability of transgenic food plants to generate protective immunity in mice against a bacterial enterotoxin.


Assuntos
Toxina da Cólera/genética , Toxina da Cólera/imunologia , Plantas Geneticamente Modificadas/genética , Vacinas/farmacologia , Animais , Anticorpos/sangue , Chlorocebus aethiops , Cólera/complicações , Cólera/imunologia , Diarreia/complicações , Diarreia/imunologia , Diarreia/terapia , Feminino , Gangliosídeo G(M1)/metabolismo , Soros Imunes , Camundongos , Camundongos Endogâmicos , Mucosa/imunologia , Solanum tuberosum/genética , Vacinas/administração & dosagem , Vacinas/genética , Células Vero/imunologia , Células Vero/microbiologia
20.
Nat Biotechnol ; 16(10): 934-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9788349

RESUMO

Oral administration of disease-specific autoantigens can prevent or delay the onset of autoimmune disease symptoms. We have generated transgenic potato plants that synthesize human insulin, a major insulin-dependent diabetes mellitus autoantigen, at levels up to 0.05% of total soluble protein. To direct delivery of plant-synthesized insulin to the gut-associated lymphoid tissues, insulin was linked to the C-terminus of the cholera toxin B subunit (CTB). Transgenic potato tubers produced 0.1% of total soluble protein as the pentameric CTB-insulin fusion, which retained GM1-ganglioside binding affinity and native antigenicity of both CTB and insulin. Nonobese diabetic mice fed transformed potato tuber tissues containing microgram amounts of the CTB-insulin fusion protein showed a substantial reduction in pancreatic islet inflammation (insulitis), and a delay in the progression of clinical diabetes. Feeding transgenic potato tissues producing insulin or CTB protein alone did not provide a significant reduction in insulitis or diabetic symptoms. The experimental results indicate that food plants are feasible production and delivery systems for immunotolerization against this T cell-mediated autoimmune disease.


Assuntos
Toxina da Cólera/genética , Diabetes Mellitus Tipo 1/prevenção & controle , Insulina/genética , Proteínas Recombinantes de Fusão/genética , Animais , Toxina da Cólera/química , Diabetes Mellitus Tipo 1/imunologia , Humanos , Insulina/imunologia , Camundongos , Camundongos Endogâmicos NOD , Plantas Geneticamente Modificadas , Proteínas Recombinantes de Fusão/química , Solanum tuberosum/genética
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