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1.
Front Genet ; 14: 1198203, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745845

RESUMO

Protein misfolding is a common intracellular occurrence. Most mutations to coding sequences increase the propensity of the encoded protein to misfold. These misfolded molecules can have devastating effects on cells. Despite the importance of protein misfolding in human disease and protein evolution, there are fundamental questions that remain unanswered, such as, which mutations cause the most misfolding? These questions are difficult to answer partially because we lack high-throughput methods to compare the destabilizing effects of different mutations. Commonly used systems to assess the stability of mutant proteins in vivo often rely upon essential proteins as sensors, but misfolded proteins can disrupt the function of the essential protein enough to kill the cell. This makes it difficult to identify and compare mutations that cause protein misfolding using these systems. Here, we present a novel in vivo system named Intra-FCY1 that we use to identify mutations that cause misfolding of a model protein [yellow fluorescent protein (YFP)] in Saccharomyces cerevisiae. The Intra-FCY1 system utilizes two complementary fragments of the yeast cytosine deaminase Fcy1, a toxic protein, into which YFP is inserted. When YFP folds, the Fcy1 fragments associate together to reconstitute their function, conferring toxicity in media containing 5-fluorocytosine and hindering growth. But mutations that make YFP misfold abrogate Fcy1 toxicity, thus strains possessing misfolded YFP variants rise to high frequency in growth competition experiments. This makes such strains easier to study. The Intra-FCY1 system cancels localization of the protein of interest, thus can be applied to study the relative stability of mutant versions of diverse cellular proteins. Here, we confirm this method can identify novel mutations that cause misfolding, highlighting the potential for Intra-FCY1 to illuminate the relationship between protein sequence and stability.

2.
J Viral Hepat ; 25(8): 945-951, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29478258

RESUMO

Hepatocellular carcinoma (HCC) is a serious complication of hepatitis C virus (HCV) infection. Sustained virologic response (SVR) for HCV is associated with a reduction in cirrhosis, HCC and mortality and their associated costs. Japanese HCV patients are older with higher prevalence of HCC. Here we used a decision-analytic Markov model to estimate the economic benefit of HCV cure by reducing HCC and DCC burden in Japan. A cohort of 10 000 HCV genotype 1b (GT1b) Japanese patients was modelled with a hybrid decision tree and Markov state-transition model capturing natural history of HCV over a lifetime horizon. Treatment options were approved all-oral direct-acting anti-virals (DAAs) vs no treatment. Treatment efficacy was based on clinical trials and transition rates and costs obtained from Japan-specific data. Cases of HCC, decompensated cirrhosis (DCC) and quality-adjusted life years (QALYs) were projected for patients treated with DAAs vs NT. QALYs were monetized using a willingness-to-pay threshold of ¥4-to-¥6 million. Incremental savings with treatment were calculated by adding the projected cost of complications avoided to the monetized gains in QALYs. The model showed that DAA treatment vs no treatment, reduces 2057 cases of HCC and 1478 cases of decompensated cirrhosis and saves ¥850 446.73 and ¥338 229.90 per patient (ppt). Additionally, treatment can lead to additional 2.64 QALYs gained per patient. The indirect economic gains associated with treatment-related QALY improvements were ¥10 576 000, ¥13 220 000 and ¥15 864 000 ppt (willingness-to-pay thresholds of ¥4 million, ¥5 million and ¥6 million). Total economic savings of treatment with DAAs (vs no treatment) was ¥7 526 372.63, ¥10 170 372.63 and ¥12 814 372.63, at these different willingness-to-pay thresholds. In conclusion treatment of HCV GT1b with all-oral DAAs in Japan can lead to significant direct and indirect savings related to avoidance of HCC and DCC.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/prevenção & controle , Custos e Análise de Custo , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/prevenção & controle , Falência Hepática/prevenção & controle , Antivirais/economia , Carcinoma Hepatocelular/economia , Carcinoma Hepatocelular/epidemiologia , Estudos de Coortes , Hepatite C Crônica/epidemiologia , Humanos , Japão/epidemiologia , Cirrose Hepática/economia , Cirrose Hepática/epidemiologia , Falência Hepática/economia , Falência Hepática/epidemiologia , Prevalência , Anos de Vida Ajustados por Qualidade de Vida
3.
Bone Joint J ; 98-B(3): 387-94, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26920965

RESUMO

AIMS: The aim of this study was to evaluate the time course of changes in parameters of diffusion tensor imaging (DTI) such as fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in patients with symptomatic lumbar disc herniation. We also investigated the correlation between the severity of neurological symptoms and these parameters. PATIENTS AND METHODS: A total of 13 patients with unilateral radiculopathy due to herniation of a lumbar disc were investigated with DTI on a 1.5T MR scanner and underwent micro discectomy. There were nine men and four women, with a median age of 55.5 years (19 to 79). The changes in the mean FA and ADC values and the correlation between these changes and the severity of the neurological symptoms were investigated before and at six months after surgery. RESULTS: The mean FA values were significantly lower (p = 0.0005) and mean ADC values were significantly higher (p = 0.0115) in compressed nerves than in intact nerves. Although the FA values increased significantly at six months after surgical treatment (p = 0.020), the ADC values decreased but not significantly (p = 0.498). There were strong correlations between the DTI parameters such as the FA value and the severity of the neurological symptoms as assessed using the Japanese Orthopaedic Association (JOA) score and the Roland-Morris Disability Questionnaire (RDQ). CONCLUSION: This preliminary study suggests that it may be possible to use DTI to diagnose, quantitatively evaluate and follow-up patients with lumbar nerve entrapment. TAKE HOME MESSAGE: DTI is a potential tool for functional diagnosis of lumbar nerve damage.


Assuntos
Deslocamento do Disco Intervertebral/complicações , Vértebras Lombares/patologia , Radiculopatia/diagnóstico , Adulto , Idoso , Anisotropia , Imagem de Tensor de Difusão/métodos , Discotomia Percutânea/métodos , Feminino , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Dor Lombar/etiologia , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Período Pós-Operatório , Radiculopatia/etiologia , Índice de Gravidade de Doença , Raízes Nervosas Espinhais/patologia , Adulto Jovem
4.
Tissue Antigens ; 86(6): 406-12, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26449183

RESUMO

Significant associations of HLA-DP alleles with chronic hepatitis B (CHB) infection are evident in Asian and Arabian populations, including Japanese, Han Chinese, Korean, and Saudi Arabian populations. Here, significant associations between CHB infection and five DPB1 alleles (two susceptibility alleles, DPB1(*) 05:01 and (*) 09:01, and three protective alleles, DPB1(*) 02:01, (*) 04:01, and (*) 04:02) were confirmed in a population comprising of 2582 Japanese individuals. Furthermore, odds ratios for CHB were higher for those with both DPB1 susceptibility alleles than for those with only one susceptibility allele; therefore, effects of susceptibility alleles were additive for risk of CHB infection. Similarly, protective alleles showed an additive effect on protection from CHB infection. Moreover, heterozygotes of any protective allele showed stronger association with CHB than did homozygotes, suggesting that heterozygotes may bind a greater variety of hepatitis B-derived peptides, and thus present these peptides more efficiently to T-cell receptors than homozygotes. Notably, compound heterozygote of the protective allele (any one of DPB1*02:01, *04:01, and *04:02) and the susceptible allele DPB1*05:01 was significantly associated with protection against CHB infection, which indicates that one protective HLA-DPB1 molecule can provide dominant protection. Identification of the HLA-DPB1 genotypes associated with susceptibility to and protection from CHB infection is essential for future analysis of the mechanisms responsible for immune recognition of hepatitis B virus antigens by HLA-DPB1 molecules.


Assuntos
Cadeias beta de HLA-DP/genética , Hepatite B Crônica/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Povo Asiático/genética , Portador Sadio/epidemiologia , Portador Sadio/imunologia , Criança , Progressão da Doença , Feminino , Frequência do Gene , Genes MHC da Classe II , Predisposição Genética para Doença , Genótipo , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/imunologia , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
J Viral Hepat ; 20(4): e124-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23490380

RESUMO

Single nucleotide polymorphisms (SNPs) in the interleukin 28B gene (IL28B) are good pretreatment predictors of anti-hepatitis C virus (HCV) therapy with interferon. SNPs of the inosine triphosphatase (ITPA) gene are associated with reduced haemoglobin levels during treatment with ribavirin. The i-densy™ (Arkray, Inc.), which is based on the quenching probe (QP) method, automatically detects target genes in blood samples by fluorescence quenching within 100 min. Using a QP and primer set, a gene amplification response is generated that can quickly and easily detect a specific gene's arrangement by fluorometry. The present study was conducted to compare the utility of i-densy (QP method) with that of conventional direct sequencing (DS) for detecting SNPs in the IL28B and ITPA genes in chronic hepatitis C patients. Between June 2011 and January 2012, 73 consecutive patients underwent genotyping of IL28B, and 54 patients underwent genotyping of ITPA. All of the patients were seropositive for HCV-RNA. The IL28B and ITPA genotypes were tested for bi-allelic polymorphisms in rs8099917 (T/T, T/G and G/G; minor allele, G) and rs1127354 (C/C, C/A and A/A; minor allele, A), respectively. The results obtained with the QP method were identical to those obtained with the conventional DS method. The frequency of the IL28B genotypes TT, GT and GG were 74%, 24.7% and 1.4%, respectively, and those of the ITPA genotypes CC, AC and AA were 68.5%, 29.6% and 1.9%, respectively. These results indicate that the i-densy using the QP method can automatically, quickly and easily identify genotypes of IL28B and ITPA.


Assuntos
Técnicas de Laboratório Clínico/métodos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Testes Genéticos/métodos , Hepatite C Crônica/tratamento farmacológico , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Pirofosfatases/genética , Antivirais/efeitos adversos , Automação Laboratorial/métodos , Humanos , Interferons , Ribavirina/efeitos adversos , Inosina Trifosfatase
7.
Bone Joint Res ; 1(1): 8-12, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23610652

RESUMO

OBJECTIVES: The purpose of this study was to assess N-acetyl aspartate changes in the thalamus in patients with osteoarthritis of the hip using proton magnetic resonance spectroscopy. METHODS: Nine patients with osteoarthritis of the hip (symptomatic group, nine women; mean age 61.4 years (48 to 78)) and nine healthy volunteers (control group, six men, three women; mean age 30.0 years (26 to 38)) underwent proton magnetic resonance spectroscopy to assess the changes of N-acetyl aspartate in the thalamus. RESULTS: The ratio of N-acetyl aspartate to creatine plus phosphocreatine in the thalamus contralateral to the symptomatic hip in patients with osteoarthritis of the hip was significantly lower than the ratio of N-acetyl aspartate to creatine plus phosphocreatine in the thalamus in the control group (1.611 (range; 1.194-1.882) vs 1.355 (range; 1.043-1.502), p < 0.001). And, a strong negative correlation was detected between the ratio of N-acetyl aspartate to creatine plus phosphocreatine in the thalamus contralateral to the symptomatic hip in patients with osteoarthritis of the hip and pain duration (r = -0.83, p = 0.018). CONCLUSIONS: We evaluated the ratio of N-acetyl aspartate to creatine plus phosphocreatine in the thalamus of patients with osteoarthritis of the hip by using proton magnetic resonance spectroscopy. We concluded that the ratio of N-acetyl aspartate to creatine plus phosphocreatine in the thalamus contralateral to the symptomatic hip in patients with osteoarthritis of the hip were significantly lower than those in the thalamus of the control group, and that pain duration was strongly related to the decrease of the ratio of N-acetyl aspartate to creatine plus phosphocreatine.

8.
AJNR Am J Neuroradiol ; 32(10): 1824-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21920866

RESUMO

BACKGROUND AND PURPOSE: DTI can provide valuable structural information that may become an innovative tool in evaluating lumbar foraminal nerve root entrapment. The purpose of this study was to visualize the lumbar nerve roots and to measure their FA in healthy volunteers and patients with lumbar foraminal stenosis by using DTI and tractography with 3T MR imaging. MATERIALS AND METHODS: Eight patients with lumbar foraminal stenosis and 8 healthy volunteers underwent 3T MR imaging. In all subjects, DTI was performed with echo-planar imaging at a b-value of 800 s/mm(2) and the lumbar nerve roots were visualized with tractography. Mean FA values in the lumbar nerve roots were quantified on DTI images. RESULTS: In all subjects, the lumbar nerve roots were clearly visualized with tractography. In all patients, tractography also showed abnormalities such as tract disruption, nerve narrowing, and indentation in their course through the foramen. Mean FA values were significantly lower in entrapped roots than in intact roots. CONCLUSIONS: We demonstrated that DTI and tractography of human lumbar nerves can visualize and quantitatively evaluate lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for the diagnosis of lumbar nerve entrapment.


Assuntos
Imagem de Tensor de Difusão/métodos , Síndromes de Compressão Nervosa/patologia , Raízes Nervosas Espinhais/lesões , Raízes Nervosas Espinhais/patologia , Adulto , Idoso , Feminino , Humanos , Aumento da Imagem/métodos , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Br Poult Sci ; 51(1): 31-42, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20390567

RESUMO

1. The advantages and disadvantages of various housing systems for laying hens were compared as a pilot study for work in commercial conditions. 2. At 16 weeks of age, 284 hens were introduced into one of 6 housing systems: two types of conventional cages (small: SC; large: LC), furnished cages (small: SF; large: LF), and non-cage systems (single-tiered aviary: SA; free-range: FR). 3. We evaluated the welfare, egg production, and immune response of the birds in these housing systems, built in the same location, for 18 months. For welfare evaluation, we examined their ethology, physiology, anatomy, production, and physical condition. 4. The non-cage systems, especially FR, had a low score for freedom from pain, injury, and disease, together with other disadvantages, such as pale eggs and increased feed intake for production. However, the score for freedom to express normal behaviour was high and immune response was good in the non-cage systems. 5. In the furnished cages, behaviour was more diverse in SF than in LF, and in SF immune response was comparable with the non-cage systems. 6. For freedom from fear and distress, the non-cage systems had high scores for some indicators such as TI duration, H/L ratio and claw length, while aggressive pecking and feather pecking was worse in the housing systems with large group sizes.


Assuntos
Galinhas/crescimento & desenvolvimento , Abrigo para Animais/normas , Animais , Comportamento Animal/fisiologia , Peso Corporal/fisiologia , Osso e Ossos/fisiologia , Galinhas/sangue , Galinhas/imunologia , Galinhas/fisiologia , Ingestão de Alimentos/fisiologia , União Europeia , Feminino , Estatísticas não Paramétricas
10.
Bioorg Med Chem Lett ; 19(21): 6196-9, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19783437

RESUMO

With bioactivity-guided phenotype screenings, a potent anti-inflammatory compound f152A1 has been isolated, characterized and identified as the known natural product LL-Z1640-2. Metabolic instability precluded its use for the study on animal disease models. Via total synthesis, a potent, metabolically stabilized analog ER-803064 has been created; addition of the (S)-Me group at C4 onto f152A1 has resulted in a dramatic improvement on its metabolic stability, while preserving the anti-inflammatory activities.


Assuntos
Anti-Inflamatórios/química , Lactonas/química , Animais , Anti-Inflamatórios/farmacocinética , Desenho de Fármacos , Humanos , Interleucina-6/metabolismo , Lactonas/síntese química , Lactonas/farmacocinética , Camundongos , Microssomos Hepáticos/metabolismo
11.
Br Poult Sci ; 50(1): 39-46, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19234928

RESUMO

1. Based on our previous studies, we designed a medium-sized furnished cage with a dust bath and nest box on both sides of the cage (MFS) and evaluated its usefulness. 2. We used 180 White Leghorn layers. At the age of 17 weeks, the birds were distributed at random into one of the 4 cage designs: conventional cages (CC; 6 cages and 5 hens per cage), small (SF; 6 cages and 5 hens per cage) and medium furnished cages (MFL; 6 cages and 10 hens per cage) with a 'localised' dust bath and nest box on one side of the cage, and MFS (6 cages and 10 hens per cage). The total allocation of resources per bird was similar for all furnished cage designs. Behaviour, physical condition and production were measured in each cage. 3. Moving was more frequent in MFS and MFL than in CC and SF. The proportion of hens performing aggressive pecking and severe feather pecking was higher in MFL than CC and SF. These aggressive interactions occurred frequently in the dust bath area in MFL; however, these tendencies were not found in MFS. Egg production and egg mass were lower in MFL than in SF, while the production in MFS was similar to those in CC and SF. MFS hens laid eggs on the cage floor more often than in MFL. 4. In conclusion, these results demonstrate the possible usefulness of MFS. However, some inconsistent results and ways of improving MFS design were also identified.


Assuntos
Bem-Estar do Animal , Comportamento Animal , Galinhas/fisiologia , Abrigo para Animais , Animais , Ovos , Plumas , Feminino , Distribuição Aleatória
12.
Eur Surg Res ; 42(2): 109-17, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19122457

RESUMO

BACKGROUND: The efficacy of direct hemoperfusion with polymyxin B-immobilized fiber columns (PMX) has already been demonstrated in clinical studies for the treatment of septic shock. However, serum procalcitonin levels following PMX remain unknown. METHODS: This prospective, multicenter, nonrandomized clinical study was performed at 12 institutions. Forty-five patients with severe sepsis or septic shock due to colorectal perforation underwent PMX. Patients' outcome as well as circulating levels of endotoxin, procalcitonin and IL-6 were monitored. RESULTS: Before surgery, procalcitonin level, but not endotoxin and IL-6 levels, was elevated according to patients' septic conditions. Procalcitonin was significantly and positively correlated with sequential organ failure assessment score. Circulating levels of procalcitonin peaked 24 h after PMX treatment. Change in serum procalcitonin level was significantly higher in nonsurvivors than survivors. Nine mortalities were observed within 28 days. The best predictor for 28-day mortality was procalcitonin >85.7 ng/ml at 24 h after PMX (area under the receiver operating characteristic curve: 0.808 +/- 0.105). CONCLUSIONS: Procalcitonin may be a good indicator of severity of sepsis secondary to colorectal perforation. Furthermore, procalcitonin level at 24 h after PMX appears to predict outcome after PMX. Therefore, procalcitonin may be a useful diagnostic marker to evaluate patients' condition in candidates for PMX treatment.


Assuntos
Calcitonina/sangue , Doenças do Colo/complicações , Hemoperfusão , Perfuração Intestinal/complicações , Precursores de Proteínas/sangue , Doenças Retais/complicações , Sepse/sangue , Idoso , Antibacterianos/administração & dosagem , Peptídeo Relacionado com Gene de Calcitonina , Endotoxinas/sangue , Feminino , Humanos , Interleucina-6/sangue , Masculino , Doenças Peritoneais/sangue , Doenças Peritoneais/terapia , Polimixina B/administração & dosagem , Estudos Prospectivos , Sepse/terapia , Índice de Gravidade de Doença , Resultado do Tratamento
13.
Br Poult Sci ; 49(5): 516-24, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18836897

RESUMO

1. The objective was to determine the relation between social rank and use of resources in a small furnished cage with sufficient resources per hen (SF) and a commercial large one with less adequate allowance of facilities per hen (LF). 2. Ninety-two cross layers were used. At the age of 16 weeks, the hens were divided at random into two groups. There were 4 furnished cages with 5 birds per cage and 4 large furnished cages with 18 birds per cage. The dominance hierarchy was determined, in which highest, medium and lowest ranking hens in each cage were identified. Behaviour, use of facilities and physical conditions of these hens were measured (one in each rank category in SF, two in each in LF). 3. Dustbathing and litter scratching were more frequent in the high ranking hens than the medium and low ranked hens in LF, while no significant difference was found between them in SF. 4. No significant difference between SF and LF was found in use of nest boxes. However, pre-laying sitting tended to be less frequent in low ranking than medium and high ranking hens in LF (Social order x Cage design). In the nest box most of time was spent in pre-laying sitting by SF hens, LF high and medium ranked hens (average 94.9%). However, LF low ranking hens spent their time escaping (33.1%), pre-laying sitting (27.7%) standing (25.7%) and moving (13.5%) in the nest. 5. In the large furnished cages with less facilities per hen, high ranking hens may be expected to have priority using the dust bath. In contrast, low ranking hens rarely performed nesting behaviour fully, and spend more time using the nest box as a refuge than for laying.


Assuntos
Comportamento Animal/fisiologia , Galinhas/fisiologia , Abrigo para Animais/normas , Predomínio Social , Bem-Estar do Animal , Animais , Feminino , Oviposição
14.
Br Poult Sci ; 49(4): 396-401, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18704784

RESUMO

1. The objective of the present study was to examine the behaviour of laying hens in single-tiered aviaries with and without outdoor areas with particular reference to the proportion of each behaviour and the ways it changed. 2. In all, 144 interbred cross layers (WL/RIR cross-breed) were used. At the age of 16 weeks, the hens were divided at random into two groups and moved to single-tiered aviary (SA) and free-range systems (FR, SA with in addition an outdoor range area covered with clover) with 18 hens per pen. Behavioural observations were conducted before, during and after access to the range. 3. All behaviours using the beak (eating, grazing, drinking, preening, aggressive pecking, feather pecking, litter pecking, object pecking and mate pecking) were recorded as pecking behaviour. 4. While most of the FR hens spent their time outside foraging, the proportion of hens eating, preening, litter pecking, object pecking, aggressive pecking and feather pecking was higher in SA than in FR hens. 5. The proportion of hens performing pecking behaviour of all types was very similar in SA (61.7 +/- 2.0%) and in FR (64.0 +/- 0.8%). The proportion of hens performing overall pecking behaviour increased as pre-laying sitting decreased. 6. The proportion of hens feather pecking decreased in FR during access to range and a similar tendency was found for aggressive pecking. 7. In conclusion, the total proportion of hens pecking was almost the same regardless of whether an outdoor area was provided or not, but the incidence of different types of pecking behaviour differed between SA and FR. The risk of feather pecking in FR may be lower when an outdoor grazing area is provided, although further testing on a larger scale would be essential.


Assuntos
Agressão/fisiologia , Comportamento Animal/fisiologia , Galinhas/fisiologia , Abrigo para Animais , Bem-Estar do Animal , Animais , Ritmo Circadiano
15.
Insect Mol Biol ; 17(4): 341-50, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18651916

RESUMO

Gamma-hexachlorocyclohexane (gamma-HCH), fipronil and picrotoxinin are noncompetitive antagonists (NCAs) of L-glutamate-gated chloride channels (GluCls), yet their potencies are weaker than those on gamma-aminobutyric acid receptors (GABARs). The A302S mutation of Drosophila RDL (resistant to dieldrin) GABAR confers NCA resistance, and housefly GluCls (MdGluCls) possess S278 as the residue corresponding to the A302. Thus, the effects of S278A mutation on the NCA actions on MdGluCls were investigated. The S278A mutation resulted in enhanced blocking by NCAs of the MdGluCl response to 30 microM L-glutamate. However, such actions of gamma-HCH and picrotoxinin, but not of fipronil, on the S278A mutant were reduced with 200 microM L-glutamate. Further increases in the L-glutamate concentration led to potentiation by NCAs of the mutant response to L-glutamate.


Assuntos
Canais de Cloreto/metabolismo , Ácido Glutâmico/metabolismo , Moscas Domésticas/metabolismo , Inseticidas/farmacologia , Ativação do Canal Iônico/fisiologia , Serina/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Canais de Cloreto/genética , Relação Dose-Resposta a Droga , Hexaclorocicloexano/química , Hexaclorocicloexano/farmacologia , Potenciais da Membrana/fisiologia , Estrutura Molecular , Picrotoxina/análogos & derivados , Picrotoxina/química , Picrotoxina/farmacologia , Pirazóis/química , Pirazóis/farmacologia , Sesterterpenos , Cloreto de Sódio/farmacologia
16.
J Anim Sci ; 85(4): 1080-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17121976

RESUMO

To provide useful information on how to moderate posthandling stress, the attractiveness of different conditions to beef cattle just after release from restraint was determined. Angus heifers were individually allowed to enter a choice area after 2 min of restraint in a squeeze chute and to choose between 2 pens. After the heifer had chosen a pen, it could freely access both test pens and the choice area for a further 5 min. In Exp. 1, each heifer was given 1 of the following choices: a pen with 3 familiar heifers (PEERS) vs. a pen with a pile of hay on a metal rack (FOOD; n = 34); PEERS vs. the bare pen (BARE; n = 34); and FOOD vs. BARE (n = 35). When the choice combination was PEERS vs. BARE, more heifers chose PEERS (P < 0.05). When the choice combination was PEERS vs. FOOD, more heifers than expected tended to choose PEERS (P < 0.10), whereas FOOD and BARE did not differ. The latency to choose either pen was shorter if PEERS was 1 of the 2 choices (P < 0.01). After choosing, more heifers entered the PEERS pen than the FOOD (P < 0.05) or BARE (P < 0.01) pens. In Exp. 2, another 86 heifers were given 1 of the following choices: a pen with a familiar handler standing inside (STI) vs. a pen with a novel object (NO; n = 29); a pen with the handler standing outside the pen (STO) vs. NO (n = 29); a pen in which the handler was sitting inside (SI) vs. NO (n = 28). Fewer heifers chose the pen with the human (STI, STO, and SI; all P < 0.01). Except for the choice of STO vs. NO, the number of heifers that had voluntarily chosen either pen was larger than expected (STI and SI; both P < 0.01). The number of times in which the NO pen was entered was greater than the STI and STO (P < 0.01), although the number of times in which the SI and NO pens were entered was not different. More heifers avoided the human, particularly a standing human. In conclusion, just after handling with restraint, returning cattle to the group of peers and not approaching the cattle needlessly should moderate their stress.


Assuntos
Comportamento Animal/fisiologia , Bovinos/fisiologia , Bovinos/psicologia , Comportamento de Escolha/fisiologia , Restrição Física/veterinária , Estresse Fisiológico/veterinária , Ração Animal , Animais , Feminino , Aprendizagem em Labirinto , Restrição Física/psicologia , Comportamento Social , Estresse Fisiológico/fisiopatologia , Estresse Fisiológico/psicologia
17.
Oncogene ; 25(45): 6101-12, 2006 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-16682950

RESUMO

The programmed cell death 4 (PDCD4) gene was originally identified as a tumor-related gene in humans and acts as a tumor-suppressor in mouse epidermal carcinoma cells. However, its function and regulatory mechanisms of expression in human cancer remain to be elucidated. We therefore investigated the expression of PDCD4 in human hepatocellular carcinoma (HCC) and the role of PDCD4 in human HCC cells. Downregulation of PDCD4 protein was observed in all HCC tissues tested compared with corresponding noncancerous liver, as revealed by Western blotting or immunohistochemical staining. Human HCC cell line, Huh7, transfected with PDCD4 cDNA showed nuclear fragmentation and DNA laddering characteristic of apoptotic cells associated with mitochondrial changes and caspase activation. Transforming growth factor-beta1 (TGF-beta1) treatment of Huh7 cells resulted in increased PDCD4 expression and occurrence of apoptosis, also concomitant with mitochondrial events and caspase activation. Transfection of Smad7, a known antagonist to TGF-beta1 signaling, protected cells from TGF-beta1-mediated apoptosis and suppressed TGF-beta1-induced PDCD4 expression. Moreover, antisense PDCD4 transfectants were resistant to apoptosis induced by TGF-beta1. In conclusion, these data suggest that PDCD4 is a proapoptotic molecule involved in TGF-beta1-induced apoptosis in human HCC cells, and a possible tumor suppressor in hepatocarcinogenesis.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Apoptose/fisiologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas de Ligação a RNA/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Idoso , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta1
18.
Insect Mol Biol ; 15(6): 773-83, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17201770

RESUMO

Ligand-gated chloride channels (LGICs) are important targets for insecticides and parasiticides. Genes encoding subunits of two LGICs, a glutamate-gated chloride channel (MdGluCl-alpha) and a gamma-aminobutyric acid (GABA)-gated chloride channel (MdRdl), were cloned from house-flies (Musca domestica L.). These genes were first expressed independently in Xenopus laevis oocytes by cRNA injection in order to investigate the pharmacology of these ligand-gated channels using two-electrode voltage-clamp electrophysiology. It was found that L-glutamate and GABA activated the MdGluCl-alpha homo-oligomers with an EC(50) value of 30 microM and the MdRdl homo-oligomers with an EC(50) value of 101 microM, respectively. Both channels were chloride ion-permeable, and the MdRdl channel was more sensitive to chloride channel blockers, such as gamma-hexachlorocyclohexane (gamma-HCH), fipronil and picrotoxinin, than the MdGluCl-alpha channel. MdGluCl-alpha required only 1-2 days of incubation after cRNA injection to be expressed in oocytes, whereas 4-7 days of incubation was necessary to achieve MdRdl expression. However, when the cRNA of MdGluCl-alpha was injected at a dose of 1% (w/w) 1 day after the injection of the cRNA of MdRdl, a significant increase in the current amplitude of responses to GABA was observed, and the incubation period necessary for MdRdl expression became shorter. These results suggest that MdGluCl-alpha assists in the expression of MdRdl when the two are coexpressed.


Assuntos
Canais de Cloreto/metabolismo , Expressão Gênica , Ativação do Canal Iônico , Muscidae/metabolismo , Oócitos/metabolismo , Xenopus laevis , Ácido gama-Aminobutírico/metabolismo , Animais , Antiparasitários/farmacologia , Agonistas dos Canais de Cloreto , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/química , Clonagem Molecular , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Agonistas GABAérgicos/farmacologia , Antagonistas GABAérgicos/farmacologia , Glutamatos/farmacologia , Hexaclorocicloexano/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Picrotoxina/análogos & derivados , Picrotoxina/farmacologia , Estrutura Quaternária de Proteína/efeitos dos fármacos , Pirazóis/farmacologia , RNA Complementar/metabolismo , Sesterterpenos , Ácido gama-Aminobutírico/farmacologia
19.
Radiat Prot Dosimetry ; 117(4): 432-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15985500

RESUMO

A method using europium-doped BaFBr imaging plates (IPs) has been studied for mapping entrance skin doses during interventional radiology (IR); the mapping is useful for detecting overlap between irradiation fields and determining the most exposed skin areas. IPs, which are two-dimensional radiation sensors made of photostimulated luminescence materials, have a linear dose response up to approximately 100 Gy, can accurately measure doses from 1 microGy to 10 Gy and can be used repeatedly. Because the energy dependence of IPs is rather high, the IPs were characterised in this study and a sensitivity variation of approximately 13% was observed for effective energies of 32.7 to 44.7 keV, which are used in IR procedures. Simulation of actual interventional cardiology procedures showed that the variation of sensitivity was within 5%, meaning that IPs are practical for measuring skin doses during IR. Moreover, the patient data can be stored online and easily called up when IR procedures must be repeated, helping to prevent radiation injuries.


Assuntos
Fluoroscopia , Radiografia Intervencionista , Radiometria/métodos , Pele/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Imagens de Fantasmas , Doses de Radiação , Sensibilidade e Especificidade
20.
Biochem Biophys Res Commun ; 326(2): 442-8, 2005 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-15582597

RESUMO

INTRODUCTION: In addition to its role in apoptosis suppression, Bcl-2 has been reported to be co-expressed with neuroendocrine markers in several tissues, leading to speculation that this oncoprotein may promote neuroendocrine differentiation. AIM: This study investigated whether Bcl-2 modulated neuroendocrine biopeptide expression. METHODS: Levels of chromogranin A, neurone specific enolase, protein gene peptide 9.5, pancreatic polypeptide, and the chromogranin-derived peptides, intervening peptide and vasostatin-1 were examined by immunocytochemistry in rat phaeochromocytoma (PC12) cell lines genetically engineered to over-express Bcl-2 and their mock-transfected controls. Intensity of fluorescence was graded using a semi-quantitative scale from (-) indicating negative expression to (+++) indicating intense positivity. RESULTS: Mann-Whitney U analysis indicated that no significant differences in expression existed between control and Bcl2 over-expressing cell lines for any of the six peptides examined. CONCLUSIONS: The results of this study do not support the hypothesis that Bcl-2 promotes the acquisition of a neuroendocrine phenotype.


Assuntos
Diferenciação Celular , Sistemas Neurossecretores/citologia , Sistemas Neurossecretores/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Biomarcadores/análise , Cromogranina A , Cromograninas/metabolismo , Ciclo-Oxigenase 2 , Regulação da Expressão Gênica , Imuno-Histoquímica , Isoenzimas/metabolismo , Células PC12 , Prostaglandina-Endoperóxido Sintases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Regulação para Cima
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