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1.
Stud Mycol ; 104: 87-148, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37351543

RESUMO

Fusarium species are important cereal pathogens that cause severe production losses to major cereal crops such as maize, rice, and wheat. However, the causal agents of Fusarium diseases on cereals have not been well documented because of the difficulty in species identification and the debates surrounding generic and species concepts. In this study, we used a citizen science initiative to investigate diseased cereal crops (maize, rice, wheat) from 250 locations, covering the major cereal-growing regions in China. A total of 2 020 Fusarium strains were isolated from 315 diseased samples. Employing multi-locus phylogeny and morphological features, the above strains were identified to 43 species, including eight novel species that are described in this paper. A world checklist of cereal-associated Fusarium species is provided, with 39 and 52 new records updated for the world and China, respectively. Notably, 56 % of samples collected in this study were observed to have co-infections of more than one Fusarium species, and the detailed associations are discussed. Following Koch's postulates, 18 species were first confirmed as pathogens of maize stalk rot in this study. Furthermore, a high-confidence species tree was constructed in this study based on 1 001 homologous loci of 228 assembled genomes (40 genomes were sequenced and provided in this study), which supported the "narrow" generic concept of Fusarium (= Gibberella). This study represents one of the most comprehensive surveys of cereal Fusarium diseases to date. It significantly improves our understanding of the global diversity and distribution of cereal-associated Fusarium species, as well as largely clarifies the phylogenetic relationships within the genus. Taxonomic novelties: New species: Fusarium erosum S.L. Han, M.M. Wang & L. Cai, Fusarium fecundum S.L. Han, M.M. Wang & L. Cai, Fusarium jinanense S.L. Han, M.M. Wang & L. Cai, Fusarium mianyangense S.L. Han, M.M. Wang & L. Cai, Fusarium nothincarnatum S.L. Han, M.M. Wang & L. Cai, Fusarium planum S.L. Han, M.M. Wang & L. Cai, Fusarium sanyaense S.L. Han, M.M. Wang & L. Cai, Fusarium weifangense S.L. Han, M.M. Wang & L. Cai. Citation: Han SL, Wang MM, Ma ZY, Raza M, Zhao P, Liang JM, Gao M, Li YJ, Wang JW, Hu DM, Cai L (2023). Fusarium diversity associated with diseased cereals in China, with an updated phylogenomic assessment of the genus. Studies in Mycology 104: 87-148. doi: 10.3114/sim.2022.104.02.

2.
Persoonia ; 48: 1-53, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38234691

RESUMO

The genus Fusarium includes numerous important plant and human pathogens, as well as many industrially and commercially important species. During our investigation of fungal diversity in China, a total of 356 fusarioid isolates were obtained and identified from diverse diseased and healthy plants, or different environmental habitats, i.e., air, carbonatite, compost, faeces, soil and water, representing hitherto one of the most intensive sampling and identification efforts of fusarioid taxa in China. Combining morphology, multi-locus phylogeny and ecological preference, these isolates were identified as 72 species of Fusarium and allied genera, i.e., Bisifusarium (1), Fusarium (60), and Neocosmospora (11). A seven-locus dataset, comprising the 5.8S nuclear ribosomal RNA gene with the two flanking internal transcribed spacer (ITS) regions, the intergenic spacer region of the rDNA (IGS), partial translation elongation factor 1-alpha (tef1), partial calmodulin (cam), partial RNA polymerase largest subunit (rpb1), partial RNA polymerase second largest subunit (rpb2) gene regions, and partial ß-tubulin (tub2), were sequenced and employed in phylogenetic analyses. A genus-level phylogenetic tree was constructed using combined tef1, rpb1, and rpb2 sequences, which confirmed the presence of four fusarioid genera among the isolates studied. Further phylogenetic analyses of two allied genera (Bisifusarium and Neocosmospora) and nine species complexes of Fusarium were separately conducted employing different multi-locus datasets, to determine relationships among closely related species. Twelve novel species were identified and described in this paper. The F. babinda species complex is herein renamed as the F. falsibabinda species complex, including descriptions of new species. Sixteen species were reported as new records from China. Citation: Wang MM, Crous PW, Sandoval-Denis M, et al. 2022. Fusarium and allied genera from China: species diversity and distribution. Persoonia 48: 1-53. https://doi.org/10.3767/persoonia.2022.48.01.

3.
J Nanosci Nanotechnol ; 18(2): 823-828, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448499

RESUMO

ZnO and Ag-containing ZnO (ZnO/Ag) films with the Ag/Zn molar ratio of 3.3 and 9.1%, respectively were sol-gel coated on biomedical titanium for antibacterial and bioactive surface modification. X-ray diffraction analysis indicates that ZnO peaks increase with the calcination temperature of the samples. Scanning electron microscopy and energy dispersive of X-ray analyses reveal Ag-rich white particles (300~750 nm) on ZnO/Ag samples that were calcined at 400 °C. X-ray photoelectron spectroscopy analysis of ZnO/Ag samples shows that Zn and O exist as ZnO and Ag presents in metallic state. The coating samples exhibit similar UV light-induced hydrophilic conversion behavior. Potentiodynamic polarization test in a Ca-free Hank's balanced solution demonstrates better corrosion resistance of the coating samples compared with the polished sample. In the in vitro bioactivity test using the simulated body fluid, a layer of apatite is gradually deposited on the surface of sample ZnO/9Ag after 12 days of soaking. The MTT assay test shows that ZnO and ZnO/Ag films have weak compatibility with the L929 cells. The antibacterial test against E. Coli by the disk diffusion assay reveals that antibacterial activity of the coating samples increases with silver content of the films.


Assuntos
Antibacterianos , Titânio , Óxido de Zinco , Escherichia coli , Prata , Difração de Raios X
4.
Osteoporos Int ; 26(1): 113-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25149856

RESUMO

UNLABELLED: In our paper, we systemically retrieved the eligible study evaluating whether increased incidence of subsequent vertebral fracture is associated with vertebroplasty. Main effect sizes were vertebral fracture rates reported in terms of hazard ratio (HR) for time-to-event data or relative risk (RR) for dichotomous outcome. Our results do not support the hypothesis that vertebroplasty contributes to increased risk of subsequent vertebral fracture, neither adjacent nor total vertebral fracture. INTRODUCTION: Vertebroplasty has been implicated in significant changes in vertebral strength, vertebral shape, and consequently increased risk for subsequent vertebral fracture, especially the adjacent level. Here, we further tested the hypothesis whether new-onset vertebral fracture is a natural result of osteoporosis or consequence of cement augmentation. METHODS: Relevant literatures were retrieved using PubMed, Web of Knowledge, and Cochrane Central Register of Controlled Trials (CENTRAL), supplemented by a hand-search of the reference lists of selected articles. Eligible studies assessed whether increased morbidity of subsequent vertebral fracture is associated with vertebroplasty. Main effect sizes were vertebral fracture rates reported in terms of hazard ratio (HR) for time-to-event data or relative risk (RR) for dichotomous outcome. Random-effects model was used to account for clinical or methodological heterogeneity across studies. RESULTS: Thirteen studies with a number of 2,551 individuals (1,631 in vertebroplasty group and 920 in control group) were suitable for this meta-analysis. In trials that reported adjacent vertebral fracture as time-to-event data (two trials, n = 328), we found a similar incidence of vertebral fracture in percutaneous vertebroplasty (PVP) group compared to conservative therapy (HR 0.60, 95% confidence interval 0.29 to 1.26; P = 0.18). In trials that reported overall vertebral fracture as time-to-event data (three trials, n = 704), vertebroplasty was associated with a slightly increased but non-significant risk for vertebral fracture (HR 1.14, 95% confidence interval 0.65 to 2.00; P = 0.65). The outcome was further confirmed in the secondary meta-analysis of studies that reported vertebral fracture as dichotomous data. Subgroup analysis according to study design revealed no difference either. CONCLUSIONS: Our results do not support the hypothesis that vertebroplasty contributes to increased risk of subsequent vertebral fracture, neither adjacent nor total vertebral fracture. However, adequately designed randomized controlled trials are warranted to confirm the present findings.


Assuntos
Fraturas por Osteoporose/etiologia , Fraturas da Coluna Vertebral/etiologia , Vertebroplastia/efeitos adversos , Fraturas por Compressão/etiologia , Fraturas por Compressão/cirurgia , Humanos , Fraturas por Osteoporose/cirurgia , Recidiva , Fatores de Risco , Fraturas da Coluna Vertebral/cirurgia
5.
Int J Clin Pract ; 66(2): 199-209, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22257045

RESUMO

To determine the efficacy of teriparatide supplementation for improving bone mineral density (BMD) and fracture risk in postmenopausal osteoporosis and if effects vary with factors. We identified eight randomised controlled trials (n = 2388) using electronic databases, supplemented by a hand-search of the reference lists. All trials aimed to evaluate the efficacy of daily subcutaneous teriparatide injection in postmenopausal osteoporosis. The main outcomes were fracture risk and percentage change of BMD from baseline. Data were pooled by employing a random-effect model. In trials that reported BMD as an outcome, treatment was associated with an increase of bone mass of 8.14% [95% confidence interval (CI): 6.72-9.55%; eight trials, n = 2206] in spine and 2.48% (95% CI: 1.67-3.29%; seven trials, n = 1303) at the hip. In trials that reported fracture as an outcome, treatment was associated with a 70% risk reduction in vertebral fractures (risk ratio 0.30, 95% CI: 0.21-0.44; three trials, n = 1452) and 38% risk reduction in non-vertebral fractures (risk ratio 0.62, 95% CI: 0.44-0.87; three trials, n = 1842). The PTH treatment with total calcium intake more than 1500 mg was related to a significant increase in BMD gains at total hip (1.40% vs. 3.72%; p = 0.004). However, long-term duration did not appear to contribute to differences in responsiveness to teriparatide. Evidence supports the use of teriparatide in treatment of women with postmenopausal osteoporosis who are at risk for fracture. Further studies directly comparing concurrent therapy and calcium supplement with long-term duration are warranted.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Fraturas Ósseas/prevenção & controle , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/uso terapêutico , Cálcio da Dieta/administração & dosagem , Suplementos Nutricionais , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Viés de Seleção
6.
Colorectal Dis ; 12(11): 1094-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19863609

RESUMO

AIM: Radical surgery of rectal cancer is associated with significant morbidity, and some patients with low-lying lesions must accept a permanent colostomy. The objective of this study was to evaluate the outcome of local excision followed by adjuvant radiotherapy for rectal cancer for curative purposes. METHOD: One hundred and seven patients with rectal carcinoma performed with local excision were analysed retrospectively. RESULTS: The procedures of local excision were trans-anal resection in 83 patients, trans-sacral resection in 16, trans-sphincteric local resection in five, and trans-vaginal resection in three. The overall disease-free survival rate was 80.4% (86/107), including 90.0% (54/60) for T1 and 72.3% (34/47) for T2 tumours, respectively. Eighty-two of 107 patients underwent adjuvant postoperative radiotherapy after local excision, and 25 did not, and the DFS rates between radiation and nonradiation group were significantly different for T2 [81.6% (31/38) vs 33.3% (3/9), P < 0.05], but not for T1 tumours (90.9%vs 87.5%, P > 0.05). The rates of local recurrence and distant metastasis were 13.1% (14/107) and 4.7% (5/106), respectively, and the median time to relapse was 15 months (range: 10-53) for local recurrence and 30 months (21-65) for distant recurrence. The risk factors for local recurrence were large tumour (≥3 cm), poorly differentiated adenocarcinoma and T2 tumour. CONCLUSIONS: Local excision followed adjuvant radiotherapy is an alternative and feasible technique for small T1 rectal cancer in selected cases.


Assuntos
Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Cirurgia Colorretal/métodos , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia , Radioterapia Adjuvante , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Estudos Retrospectivos , Resultado do Tratamento
7.
Hong Kong Med J ; 16(5): 400-2, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20890007

RESUMO

A 35-year-old Chinese man presented with dull pain in the right hypochondrial region for the previous 2 months. Laboratory examination revealed that his serum alpha-fetoprotein level was 1890 microg/L (reference range, 0-20 microg/L), and computed tomographic scan showed a hypodense lesion in the left liver lobe. At laparotomy, a dark reddish soft tumour (3.0 x 3.5 cm in diameter) was found in the medial segment of the liver (segment III). The tumour became markedly smaller than that before resection, and a vessel-like structure was found on the cut surface. Intra-operative pathology and postoperative histopathology examinations revealed that the tumour was a cavernous haemangioma of the liver. The serum alpha-fetoprotein level decreased to 3.5 microg/L by the fourth postoperative week. Clinicians should be aware that some rare tumours besides hepatocellular carcinoma and endodermal sinus tumours (yolk sac tumour), for example, hepatic haemangioma, can produce alpha-fetoprotein.


Assuntos
Hemangioma Cavernoso/diagnóstico , Neoplasias Hepáticas/diagnóstico , alfa-Fetoproteínas/metabolismo , Adulto , China , Seguimentos , Hemangioma Cavernoso/patologia , Hemangioma Cavernoso/cirurgia , Humanos , Laparotomia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Tomografia Computadorizada por Raios X
8.
Heliyon ; 6(3): e03609, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32258467

RESUMO

As one of the key components to support all the magnet coils, the GS faces engineering challenge to its operational safety throughout the design, qualification and manufacturing process as a result of extreme loading condition. The structural safety of GS was confirmed by both the FEM analysis and the semi-prototype engineering test after a long time of design, qualification, manufacture and assembly. Welding the cooling pipe to the flexible plate without obvious deformation as well as tightening uniformly and precisely all the tie rods to clamp the plates were carried out successfully during manufacturing. The result of final vacuum leakage test indicates that the GS can not only meet the ITER vacuum requirement but also have no slow out-gassing. The first set of GS which has passed the ITER acceptance test is to be delivered to ITER construction site soon.

9.
Clin Rheumatol ; 36(5): 1023-1029, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28342151

RESUMO

This study aims to assess the risk factors of cardiovascular disease (CVD) and to determine the association of traditional and biologic disease-modifying anti-rheumatic drugs (DMARDs) with risk for CVD in Chinese rheumatoid arthritis (RA) patients. A cross-sectional cohort of 2013 RA patients from 21 hospitals around China was established. Medical history of CVD was documented. The patients' social background, clinical manifestations, comorbidities, and medications were also collected. Of the 2013 patients, 256 had CVD with an incidence of 12.7%. Compared with non-CVD controls, RA patients with CVD had a significantly advanced age, long-standing median disease duration, more often male and more deformity joints. Patients with CVD also had higher rates of smoking, rheumatoid nodules, interstitial lung disease, and anemia. The prevalence of comorbidities, including hypothyroidism, diabetes mellitus (DM), hypertension, and hyperlipidemia, was also significant higher in the CVD group. In contrast, patients treated with methotrexate, hydroxychloroquine (HCQ), and TNF blockers had lower incidence of CVD. The multivariate analysis showed that the use of HCQ was a protective factor of CVD, while hypertension, hyperlipidemia, and interstitial lung disease were independent risk factors of CVD. Our study shows that the independent risk factors of CVD include hypertension, hyperlipidemia, and interstitial lung disease. HCQ reduces the risk of CVD in patients with RA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Doenças Cardiovasculares/epidemiologia , Vigilância da População/métodos , Medição de Risco , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Criança , China/epidemiologia , Estudos Transversais , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
11.
Surgery ; 119(5): 585-91, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8619216

RESUMO

BACKGROUND: Although they have critical roles in the defense mechanism against invading microorganisms, neutrophils may facilitate exacerbation of critical conditions associated with acute necrotizing pancreatitis by a discharge of granule contents into the organ tissues. Because of this constitution of neutrophils, the therapeutic efficacy of Urge-8, a mouse monoclonal antibody to neutrophils, on the survival of rats with experimentally induced acute necrotizing pancreatitis was investigated in vivo. METHODS: Acute pancreatitis was induced by injection of trypsin mixed with sodium chenodeoxycholic acid into pancreatic ducts. Urge-8 was infused intravenously 30 minutes after pancreatitis was induced, a series of vital signs was taken, and plasma amylase level was estimated. RESULTS: Hemorrhagic necrosis of the pancreas and intraabdominal bleeding were observed 1 hour after the pancreatitis-inducing drugs were injected, and death occurred at 240.9 +/- 24.6 minutes (mean +/- SD)in the control group. With Urge-8 administration, however, the survival time was significantly prolonged to 395.2 +/- 64.4 minutes (p = 6.0 x 10-(10) versus control). Failure in the vital signs (mean arterial pressure, heart rate, and body temperature) was significantly ameliorated by injection of Urge-8. The plasma amylase level was elevated after pancreatitis was induced and peaked at 3 hours (4915 +/- 1966 IU/L in mean +/- SD). This level was suppressed during the first 3 hours by injection of Urge-8 (3372 +/- 1223 IU/L); however, the amylase level increased thereafter, becoming comparable with the peak in the control group, and then death occurred. Arterial blood gas and plasma electrolyte analyses showed that pH, base excess, and plasma potassium levels in the group treated with monoclonal antibody were significantly improved. CONCLUSIONS: It was suggested that neutrophils play some critical role in the exacerbation of acute necrotizing pancreatitis and its related symptoms. Although not capable of preventing death in our model, treatment with the antineutrophil monoclonal antibody Urge-8 after the onset of acute pancreatitis prolonged the survival time significantly.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neutrófilos/imunologia , Pancreatite/terapia , Doença Aguda , Amilases/sangue , Animais , Pressão Sanguínea , Temperatura Corporal , Frequência Cardíaca , Infusões Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Necrose , Pancreatite/sangue , Pancreatite/fisiopatologia , Ratos , Ratos Wistar
12.
Singapore Med J ; 51(10): 813-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21103818

RESUMO

INTRODUCTION: Castleman's disease, a rare atypical lymphoproliferative disorder of the lymphoid tissue with unknown cause, remains a diagnostic challenge. This study was conducted to analyse the clinicopathological behaviour and reasonable surgical treatment for patients with abdominal Castleman's disease. METHODS: The medical records of seven patients with abdominal Castleman's disease were reviewed. RESULTS: The patients comprised two men and five women, and their median age was 42.3 (range 29-53) years. The main clinical manifestation was an abdominal mass or an enlargement of the retroperitoneal lymph node. Other clinical manifestations included anaemia, loss of body weight and hypoalbuminaemia. The mean size of the tumour was 5.5 (range 4.0-8.0) cm. Postoperatively, all the patients were diagnosed with a hyaline vascular type of the disease, and had localised manifestations of the disease. All seven patients underwent complete surgical resection, two of whom also received adjuvant irregular chemotherapy (CHOP) and steroids postoperatively. All the patients survived, with no evidence of recurrence. One patient had survived for more than two years, four patients for more than three years, and two patients for more than five years. CONCLUSION: Abdominal Castleman's disease is difficult to diagnose preoperatively, and surgical excision remains the treatment of choice, especially for localised disease.


Assuntos
Hiperplasia do Linfonodo Gigante/diagnóstico , Hiperplasia do Linfonodo Gigante/cirurgia , Adulto , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biópsia , Hiperplasia do Linfonodo Gigante/fisiopatologia , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática/patologia , Transtornos Linfoproliferativos/fisiopatologia , Transtornos Linfoproliferativos/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos
14.
Surg Today ; 25(9): 802-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8555698

RESUMO

Since the first publication on the new anastomosis technique using a biofragmentable anastomosis ring (BAR) by Hardy in 1985, various studies have been performed to investigate the superiority of this type of anastomosis, and it has since been reported that the BAR was safely used not only in large and small bowel anastomosis, but in cholecystojejunal and gastrojejunal anastomosis as well. In this study, the feasibility of the BAR for esophageal transection was investigated. Seven dogs were operated on, and one died of intraabdominal bleeding on the operative day while another died of leakage at the site of gastrotomy on the 3rd postoperative day. These deaths were all considered to be due to simple technical errors not directly related to the use of the BAR. The postoperative recovery of the other five dogs was uneventful, and the ring eventually disintegrated into several small fragments that passed out of the body in the faces between the 14th and 21st postoperative days. The dogs were killed on the 28th postoperative day, and both gross and histological examinations, revealed that the transection had been successful. Neither leakage nor significant stenosis at the site of transection was found. Our results suggested that the BAR could be used for esophageal transection and is thus recommended as an easy-to-learn, time-saving, and safe technique for esophageal operations.


Assuntos
Anastomose Cirúrgica/instrumentação , Sulfato de Bário , Esôfago/cirurgia , Ácido Poliglicólico , Suturas , Animais , Cães , Desenho de Equipamento , Esôfago/patologia , Deiscência da Ferida Operatória/patologia , Cicatrização/fisiologia
15.
Int J Pept Protein Res ; 15(4): 355-64, 1980 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6106638

RESUMO

Laser Raman spectroscopy has been used to study the conformations of somatostatin and some selected analogues in aqueous solution. The results indicate that the CS-SC dihedral angles of somatostatin and of these analogues (except [Ala3,14]-SS, which has no disulfide bond) are within 20 degrees of +/- 85 degrees, and the SS-CC dihedral angles are predominantly in the range of 50 degrees-180 degrees. Furthermore, from the behavior of the amide I' and amide III bands, it appears that somatostatin adopts a beta-pleated sheet structure, whereas its analogues are less ordered (to varying degrees).


Assuntos
Somatostatina , Somatostatina/análogos & derivados , Sequência de Aminoácidos , Animais , Conformação Proteica , Ratos , Somatostatina/farmacologia , Análise Espectral Raman
16.
Int J Pept Protein Res ; 17(3): 297-315, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7287301

RESUMO

A conformational study has been carried out on a series of linear proline-containing oligopeptides (ZGP, ZGPL, ZGPLG and ZGPLGP) in both the crystalline state and in DMSO-d6 solution, using Raman and n.m.r. spectroscopy. The amide I and III bands in the Raman spectra of the crystalline forms indicate the presence of the type I beta-bend conformation in ZGPLG and ZGPLGP, but not in ZGP and ZGPL. This result is in agreement with X-ray data on these molecules. The Raman spectra of these peptides in solution indicate that more than one conformation is present, i.e. that the beta-bend structure of the solid form of ZGPLG and ZGPLGP is destabilized by DMSO-d6. 13C and 1H n.m.r. data also demonstrate the presence of more than one conformation in ZGP, ZGPL, ZGPLG and ZGPLGP in DMSO-d6 solution. These isomers differ in their conformation (cis and trans) about their Gly-Pro peptide bonds and possibly about the c alpha-C' bond of the C-terminal proline in ZGPLGP. For ZGP, ZGPL, ZGPLG and ZGPLGP, the ensemble of conformations in DMSO-d6 includes C5 and C7 hydrogen-bonded rings; in addition, ZGPLGP may contain a small percentage of a beta-bend conformation (at Pro2-Leu3) with trans peptides in both Gly-Pro moieties.


Assuntos
Oligopeptídeos , Prolina , Cristalização , Isomerismo , Espectroscopia de Ressonância Magnética , Conformação Proteica , Soluções , Análise Espectral Raman
17.
Int J Pept Protein Res ; 16(3): 173-81, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7461899

RESUMO

The Raman spectrum of [Leu5]-enkephalin in the solid state indicates the presence of a type I' beta bend, in agreement with X-ray data of Smith & Griffin (1978). In solution, this molecule takes on different conformations in different solvents. In DMSO-d6, it forms a beta-bend structure whereas in water it exists as an ensemble of conformations.


Assuntos
Endorfinas , Encefalinas , Dimetil Sulfóxido , Encefalina Leucina , Conformação Proteica , Solventes , Espectrofotometria Infravermelho , Análise Espectral Raman , Água , Difração de Raios X
18.
Dig Surg ; 20(2): 107-14, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12686777

RESUMO

BACKGROUND/AIM: Cyclooxygenase-2 (COX-2) is one of the key isoenzymes in the production of prostaglandins, and is believed to be involved in carcinogenesis. This study was conducted to examine the role of COX-2 in the development and biological behavior of stomach cancer. METHODS: Expression of COX-2 at the mRNA and protein levels was analyzed using RT-PCR and immunoblotting assay in 50 cancerous and corresponding non-cancerous tissue specimens. Also, COX-2 expression was detected by an immunohistochemical method in 55 paraffin-embedded gastric adenocarcinoma tissues. RESULTS: Of the 50 carcinoma tissue samples analyzed, 38 (76.0%) had overexpression of COX-2 as compared to the paired non-cancerous specimens. The overexpression of COX-2 (91.7%) was more prevalent in tumors with sizes of >5 cm than those (61.5%) of 6 metastatic nodes compared to those with

Assuntos
Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia , Adenocarcinoma/mortalidade , Adulto , Idoso , Sequência de Bases , Biomarcadores Tumorais/análise , Biópsia por Agulha , Western Blotting , Estudos de Casos e Controles , Técnicas de Cultura , Ciclo-Oxigenase 2 , Feminino , Humanos , Imuno-Histoquímica , Isoenzimas/análise , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estadiamento de Neoplasias , Probabilidade , Prognóstico , Prostaglandina-Endoperóxido Sintases/análise , RNA Mensageiro/análise , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Neoplasias Gástricas/mortalidade
19.
Biochemistry ; 20(7): 1778-84, 1981 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-7225358

RESUMO

The interaction of inhibitors with the active site of arsanilazocarboxypeptidase A has been investigated by means of resonance Raman spectroscopy. The resonance Raman bands of the active-site azotyrosine-248 residue have been shown previously to be sensitive to its state of ionization and its interactions with nearby groups. In particular, the azophenol form of azotyrosine-248 can adopt two different coexisting conformations that differ with respect to the presence or absence of an intramolecular hydrogen bond between the phenolic proton and a nitrogen atom of the azo group. Each of these conformations exhibits characteristic vNN and v phi N azo stretching frequencies. The relative concentrations of these two forms, revealed by resonance Raman spectroscopy, are a sensitive probe of the hydrogen bond accepting ability of the local environment. The present study shows that the binding of L-benzylsuccinate, phenylacetate, L-phenyllactate, and beta-phenylpropionate markedly perturbs the distribution of the intra- and intermolecularly hydrogen-bonded forms of azotyrosine-248 in water. In contrast, glycyl-L-tyrosine and L-phenylalanine leave this distribution unperturbed. These results, taken jointly with other data on inhibitor binding, serve to identify common binding sites for groups of inhibitors and result in plausible suggestions concerning the interactions between azotyrosine-248 and these inhibitors that lead to binding.


Assuntos
Carboxipeptidases , Succinatos/farmacologia , Ácido Arsanílico/análogos & derivados , Ácido Arsanílico/antagonistas & inibidores , Compostos Azo/antagonistas & inibidores , Sítios de Ligação , Carboxipeptidases/antagonistas & inibidores , Ligação Proteica , Análise Espectral Raman , Tirosina
20.
Int J Pept Protein Res ; 16(3): 183-90, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7461900

RESUMO

The state of ionization of [Leu5]-enkephalin in the crystal and in solution was studied with the aid of Raman, i.r., and n.m.r. techniques. The results indicate that, in the crystal, enkephalin adopts the dipolar ion form. In water near neutral pH, enkephalin also exists in the dipolar ion form whereas in DMSO-d6 it is a mixture of the dipolar ion and uncharged species. The pK's of alpha-amino and alpha-carboxyl groups are probably closer to each other in DMSO than in H2O.


Assuntos
Endorfinas , Encefalinas , Cristalização , Dimetil Sulfóxido , Encefalina Leucina , Concentração de Íons de Hidrogênio , Íons , Espectroscopia de Ressonância Magnética , Soluções , Espectrofotometria Infravermelho , Análise Espectral Raman
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