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1.
Zhonghua Yi Xue Za Zhi ; 101(9): 636-640, 2021 Mar 09.
Artigo em Zh | MEDLINE | ID: mdl-33685045

RESUMO

Objective: To explore The feasibility of digital guidance drill templates assisted expansive open-door laminoplasty. Methods: Ten specimens of normal adult cervical spine (C3-7) were selected, including six males and four females. The specimens aged 42-67 years, with an average age of (43.6±4.2) years. After CT scanning, the date was imported into Mimics software in DICOM format. 3D models were reconstructed and the position and depth of troughs on the open side and hinge side were selected for expansive open-door laminoplasty. Drill templates were designed and exported in STL, manufactured by 3D printing finally. Then drill templates were attached to the posterior part of cervical lamina and spinous process. Under guidance of templates, troughs of both sides were conducted by using a high-speed drill. Then the lamina is elevated and instrumentations were implanted. Postoperative CT scanning was conducted to record the fracture of trough on the hinge side. 3D reconstruction was performed again to compare the position and depth between theory and actual trough on both sides by paired t test. Results: A total of 50 drill templates were designed and manufactured. There was no occurrence of hinge fracture after operation. In C3-7, the distance range between the theory position of troughs on the open side and the midline was 11.8-14.4 mm, while in actual it was 11.4-14.0 mm. The distance range between the theory position of troughs on the hinge side and the midline was 11.6-14.3 mm; in actual, it was 10.9-14.0 mm. The theory depth range of trough on the hinge side was 3.0-3.8 mm, while the actual depth was 3.1-3.8 mm. According to the statistical analysis, the difference in the position of trough on the open side, the position of trough on the hinge side and the depth of trough on the hinge side between theory and actual were not statistically significant (all P>0.05). Conclusion: Digital guided template assisted open-door laminoplasty is a feasible technique, which can improve the accuracy and safety of the position and depth of the trough, and has clinical application value.


Assuntos
Laminoplastia , Adulto , Idoso , Vértebras Cervicais/cirurgia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
2.
Zhonghua Yi Xue Za Zhi ; 100(41): 3235-3239, 2020 Nov 10.
Artigo em Zh | MEDLINE | ID: mdl-33167110

RESUMO

Objective: To evaluate the best entry region and trajectory of anterior transpedicular root screws (ATPRS). Methods: From January 2018 to May 2019, 50 cervical CT date integral of healthy people were selected from Ningbo No. 6 Hospital and were confirmed no obvious defect. Of these, 24 cases were males and 26 were females, aged 20-49 (32±5) years. The CT data was imported into Mimics by DICOM format, then 3D reconstruction was performed. In the coronal plane, the area from the centreline of the anterior of C(3-7) to the left Z-line(marked a line through the intersection of the anterior of the luschak joint and upper endplates, parallel to the centralline of the anterior of the vertebral body) was divided into nine areas. Then virtual screw with diameter of 3.5 mm was inserted. Record the length of screw of each area (L), the angle between screw and the posterior of the vertebral body in horizontal plane(α), the angle between screw and the anterior of the vertebral body in sagittal plane (ß), individually. The data between groups were compared by independent sample t test. Results: The best regions were zone 9 of C(3), C(4); zone 8, 9 of C(5); zone 2-3, 5-9 of C(6); zone 1-9 of C(7) in men. And these were zone 9 of C(3); zone 3, 6, 8 and 9 of C(4), C(5); zone 2-3, 5-9 of C(6); zone 1-9 of C(7) in women. The distribution of best region was almost the same in men and women, zone 9 of each segment was the best region, and the screw length was the longest. It increased gradually from C(3) to C(7). C(3) had the least region, C(4) and C(5) had less, while C(6) and C(7) had the most. The horizontal angle of C(3-7) in men and women were 44.0°-47.2°, 40.2°-45.3° in zone 1, 4 and 7, respectively; 35.1°-41.4°, 34.6°-38.7° in zone 2, 5 and 8, respectively; 30.0°-37.2°, 30.2°-34.5° in zone 3, 6 and 9, respectively; and it demonstrated a gradually decreased trend. The sagittal angle of C(3-7) in men and women was 85.3°-97.4°, 80.5°-88.9° in zone 1-3, respectively; 101.2°-113.7°, 101.0°-109.3° in zone 4-6, respectively; 116.6°-128.8°, 119.9°-125.3° in zone 7-9, respectively; and it demonstrated a gradually increased trend. There was no significant difference in the horizontal and sagittal angle between men and women (both P>0.05). Conclusions: Anterior transpedicular root screw is a feasible internal fixation technique. It has wide region and the Z-line can be used as a reference for screw placement.


Assuntos
Parafusos Ósseos , Vértebras Cervicais , Adulto , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Bull Entomol Res ; 102(4): 477-88, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22314051

RESUMO

Phosphoglucose isomerase (PGI) plays an important role in energy metabolism, and it is documented that PGI exhibits an extensive polymorphism which can affect insects' fitness and adaptation. In this paper, we studied the structural characteristics and polymorphism of pgi gene in the fall webworm (Hyphantria cunea), an important invasive pest in some European and Asian countries. A 2110-bp pgi full-length cDNA encoding a polypeptide of 556 amino acids was obtained from H. cunea. The pgi full-length in the H. cunea genomic DNA was 14,332 bp with 12 exons and 11 introns, similar to the structures of pgi in other Lepidoptera species. We compared the structures of pgi in different insect species. Moreover, thirteen pgi genotypes comprised of five alleles were identified in the Chinese population. Genotypes pgi-cd, pgi-cc and pgi-ce were the most prevalent with over 70% of individuals allocated to them. Four out of five alleles were sequenced the cDNA full-length. Thirty stably variable sites were found among them with five non-synonymous mutation sites. The frequencies of alleles and genotypes were variable in different Chinese geographic subpopulations. Moreover, comparison of pgi mRNA expression levels in each stage of the moth's lifecycle showed that a high expression level was in the 6th instar larval stage, followed by that in the egg and adult stages. The results will provide a basis for further study of the role of different alleles and genotypes of PGI on fitness and adaptation of the moth H. cunea.


Assuntos
Glucose-6-Fosfato Isomerase/genética , Mariposas/genética , Polimorfismo Genético/fisiologia , Adaptação Fisiológica , Animais , China , Espécies Introduzidas , Larva/fisiologia , Óvulo/fisiologia , Filogenia , Pupa/fisiologia
4.
Artigo em Zh | MEDLINE | ID: mdl-35266352

RESUMO

OBJECTIVE: To analyze the dynamic changes of schistosomiasis in Poyang County of Jiangxi Province from 2004 to 2020, so as to provide insight into the development of the schistosomiasis elimination strategy. METHODS: Schistosomiasis control data were captured from Poyang County from 2004 to 2020, and the epidemiological data of schistosomiasis were collected from national schistosomiasis surveillance sites in Poyang County from 2005 to 2020. The endemic status of schistosomiasis was analyzed in Poyang County from 2004 to 2020, and a Joinpoint regression analysis was performed to investigate the trends of schistosomiasis in Poyang County from 2004 to 2020. RESULTS: The sero-prevalence and egg-prevalence of human Schistosoma japonicum infections reduced from 24.39% (24 976/102 397) and 4.53% (259/5 721) in 2004 to 5.37% (2 421/45 100) [annual percent change (APC) = average annual percent change (AAPC) = -8.64%] and 0 (0/3 963) in 2020 (APC = AAPC = -32.07%) in Poyang County, and the trends were both significant (both P < 0.01). The sero-prevalence of S. japonicum infections reduced from 1.21% (294/24 332) in bovines in 2013 to 0.58% (35/5 999) in 2020 in Poyang County, with one turning point (AAPC = -8.20%, P > 0.05). There were no townships or villages with emerging snail habitats in Poyang County from 2004 to 2020, and there were three turning points of trend in the proportion of snail areas detected in total snail areas (AAPC = -2.30%, P > 0.01). The sero-prevalence and adjusted prevalence of S. japonicum infections reduced from 60.82% (742/1 220) and 10.16% (124/1 220) in local residents in 2005 to 5.73% (70/1 221) and 0 in 2020 in national schistosomiasis surveillance sites of Poyang County, and the trends for sero-prevalence (APC = AAPC = 17.47%, P < 0.01) and adjusted prevalence of S. japonicum infections (APC = AAPC = -44.92%, P < 0.01) were both statistically significant. S. japonicum infections were identified in 10 (2005) and 2 local livestock (2007), with prevalence of 10.00% (10/100) and 13.33% (2/15), respectively, and S. japonicum infections were detected in snails in 2008 and 2009; however, no positive samples of mixed O. hupensis were detected by loop-mediated isothermal amplification. CONCLUSIONS: The endemic situation of schistosomiasis control had remarkably reduced in Poyang County from 2004 to 2020; however, there are still challenges for consolidating schistosomiasis control achievements and even elimination of schistosomiasis.


Assuntos
Esquistossomose Japônica , Esquistossomose , Animais , Bovinos , China/epidemiologia , Ecossistema , Humanos , Gado , Prevalência , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Esquistossomose Japônica/epidemiologia
5.
Heredity (Edinb) ; 100(4): 356-65, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18091770

RESUMO

Pinewood nematode (Bursaphelenchus xylophilus) is an invasive species that causes a destructive forest disease-pine wilt disease. This disease has been prevalent in some countries in Asia since the 1970s. An amplified fragment length polymorphism survey was used to compare the genetic variation of native and invasive nematode populations in China and to examine the changes in genetic diversity during the invasion process. The genetic diversity of Chinese populations was slightly higher than that of American populations. Analysis of groups sampled from different invasive stages in China, showed that no obvious change in genetic diversity. Hence, genetic drift and founder effects are not obvious in the invasion process. Phylogenetic analysis showed that Chinese pinewood nematode populations were closer to Japanese populations than to American populations. On the basis of the genetic relationships among samples, two major invasion pathways in China are suggested. One is from Guangdong to Anhui and Zhejiang, and the other is from Guangdong to Jiangsu and then from Jiangsu to Hubei, Guizhong and Congqing. The results imply that it is important to reinforce both domestic and international quarantine to control the spread of pinewood nematode.


Assuntos
DNA de Helmintos/genética , Árvores/parasitologia , Tylenchida/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , China , Variação Genética , Filogenia , Tylenchida/classificação
6.
Structure ; 5(4): 559-70, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9115444

RESUMO

BACKGROUND: Heterogeneous nuclear ribonucleoprotein (hnRNP) A1 is one of the most abundant core proteins of hnRNP complexes in metazoan nuclei. It behaves as a global regulator of alternative pre-mRNA splicing by antagonizing the activities of several serine/arginine-rich splicing factors (SR proteins), resulting in the activation of distal alternative 5' splice sites and skipping of optional exons. Purified hnRNP A1 has nucleic acid annealing activity. The protein also shuttles continuously between the nucleus and the cytoplasm, a process mediated by signals within its C-terminal glycine-rich domain. The N-terminal region of human hnRNP A1, termed unwinding protein 1 (UP1), contains two RNA-recognition motifs (RRMs), RRM1 and RRM2. Understanding the structural elements by which hnRNP A1 interacts with RNA will have broad implications for studies of RNA processing. RESULTS: The crystal structure of UP1 has been determined to 1.9 A resolution. Each RRM independently adopts the characteristic RRM fold, consisting of a four-stranded antiparallel beta-pleated sheet and two alpha helices packed on one side of the beta sheet. The two RRMs are antiparallel and held in close contact, mainly by two Arg-Asp ion pairs. As a result, the two four-stranded beta sheets are brought together to form an extended RNA-binding surface. A segment of the linker connecting the two RRMs is flexible in the absence of bound RNA, but the general location of the linker suggests that it can make direct contacts with RNA. Comparison with other RRM structures indicates that a short 310 helix, found immediately N-terminal to the first beta strand in RRM1, may interact with RNA directly. CONCLUSIONS: The RRM is one of the most common and best characterized RNA-binding motifs. In certain cases, one RRM is sufficient for sequence-specific and high affinity RNA binding; but in other cases, synergy between several RRMs within a single protein is required. This study shows how two RRMs are organized in a single polypeptide. The two independently folded RRMs in UP1 are held together in a fixed geometry, enabling the two RRMs to function as a single entity in binding RNA, and so explaining the synergy between the RRMs. The UP1 structure also suggests that residues which lie outside of the RRMs can make potentially important interactions with RNA.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B , Estrutura Secundária de Proteína , Proteínas de Ligação a RNA/química , RNA/metabolismo , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Ribonucleoproteína Nuclear Heterogênea A1 , Ribonucleoproteínas Nucleares Heterogêneas , Humanos , Modelos Estruturais , Dados de Sequência Molecular , RNA/química , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Eletricidade Estática
7.
Structure ; 5(3): 349-58, 1997 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9083114

RESUMO

BACKGROUND: During the cell cycle, cells progress through four distinct phases, G1, S, G2 and M; transcriptional controls play an important role at the transition between these phases. MCB-binding factor (MBF), a transcription factor from budding yeast, binds to the so-called MCB (MluI cell-cycle box) elements found in the promoters of many DNA synthesis genes, and activates the transcription of those at the G1-->S phase transition. MBF is comprised of two proteins, Mbp1 and Swi6. RESULTS: The three-dimensional structure of the N-terminal DNA-binding domain of Mbp1 has been determined by multiwavelength anomalous diffraction from crystals of the selenomethionyl variant of the protein. The structure is composed of a six-stranded beta sheet interspersed with two pairs of alpha helices. The most conserved core region among Mbp1-related transcription factors folds into a central helix-turn-helix motif with a short N-terminal beta strand and a C-terminal beta hairpin. CONCLUSIONS: Despite little sequence similarity, the structure within the core region of the Mbp1 N-terminal domain exhibits a similar fold to that of the DNA-binding domains of other proteins, such as hepatocyte nuclear factor-3gamma and histone H5 from eukaryotes, and the prokaryotic catabolite gene activator. However, the structure outside the core region defines Mbp1 as a larger entity with substructures that stabilize and display the helix-turn-helix motif.


Assuntos
Replicação do DNA/fisiologia , DNA Fúngico/metabolismo , Proteínas Fúngicas/química , Conformação Proteica , Proteínas de Saccharomyces cerevisiae , Fatores de Transcrição/química , Sequência de Aminoácidos , Sítios de Ligação , Ciclo Celular , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Proteínas Fúngicas/metabolismo , Sequências Hélice-Volta-Hélice , Fator 3-gama Nuclear de Hepatócito , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Nucleares/química , Ligação Proteica , Proteínas Recombinantes de Fusão/química , Saccharomyces cerevisiae/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/metabolismo
8.
Spine (Phila Pa 1976) ; 20(20): 2203-10, 1995 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8545713

RESUMO

STUDY DESIGN: This study compared the efficacy of characterized 50/50 hydroxyapatite/beta-tricalcium phosphate ceramics of 30%, 50%, and 70% porosity and autograft to promote interbody spinal fusion at C2-C3 and C5-C6 in 24 goats: 12 at 3 months and 12 at 6 months. OBJECTIVES: Radiographs, histology, dual energy x-ray absorptiometry analysis, and biomechanical testing were used to evaluate the ability of the 30%, 50%, and 70% porous 50/50 hydroxyapatite/beta-tricalcium phosphate ceramics and autograft to promote cervical interbody fusion. SUMMARY OF BACKGROUND DATA: The conundrum in the use of calcium phosphates for interbody fusion is what porosity is most effective to promote ingrowth yet strong enough to resist compressive stresses found in the spine? It is known that the ability for bone ingrowth increases and the compressive strength decreases as porosity of the ceramic is increased. Dense ceramics remain intact but may be surrounded by fibrous tissue. Porous ceramics have good ingrowth but may fracture. METHODS: Radiographs were evaluated for fusion and fracture or collapse of the ceramics or autograft. Dual energy x-ray absorptiometry was used to evaluate the fusion mass. Treated motion segments underwent biomechanical testing to quantify the flexibility of the segment. Undecalcified and decalcified histologic analysis were performed to evaluate the presence or absence of a bony union. RESULTS: Thirty percent, 50%, and 70% porous ceramics had better radiographic fusion scores than the autograft at 3 and 6 months. Incidence of ceramic fracture did not increase with porosity and was equivalent to the collapse of autograft, although ceramics maintained disc height when fracture occurred. No statistically significant differences were found between autograft and the porous ceramics with biomechanical testing and peri-implant bone mineral density values as measured by dual energy x-ray absorptiometry. At 3 months, histologic analysis showed a union rate of 0% for autograft and 30% porous ceramic, 67% for 50% porous ceramic, and 83% for 70% porous ceramic. At 6 months, the union rate was 67% for the 30%, 50%, and 70% porous ceramics and 50% for autograft. CONCLUSIONS: Thirty percent, 50%, and 70% porous ceramics performed equal to or better than autogenous bone after 3 and 6 months. There may be promise for the use of 50/50 hydroxyapatite/beta-tricalcium phosphate in spine surgery as the need to harvest autograft from the iliac crest is obviated, and complications and cost associated with the harvest are avoided.


Assuntos
Substitutos Ósseos , Fosfatos de Cálcio , Cerâmica , Vértebras Cervicais/cirurgia , Durapatita , Fusão Vertebral/métodos , Animais , Transplante Ósseo/métodos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/fisiopatologia , Modelos Animais de Doenças , Cabras , Teste de Materiais , Osseointegração/fisiologia , Porosidade , Radiografia , Amplitude de Movimento Articular/fisiologia , Fatores de Tempo
9.
Yao Xue Xue Bao ; 25(10): 777-9, 1990.
Artigo em Zh | MEDLINE | ID: mdl-2099593

RESUMO

Dimethyl-4, 4'-dimethoxy-5, 6, 5', 6'-dimethylenedioxy-biphenyl-2, 2'-dicarboxylate (biphenyldimethyldicarboxylate; BDD), a synthetic compound, has been used in the treatment of chronic hepatitis with good results in reducing s-GPT. Previous work in our laboratory studied its metabolites using 3H-labeled compound in combination with TLC and found that its main metabolic pathway is demethylation followed by conjugation with glucuronic acid. This paper reports the isolation and identification of a metabolite of BDD from rat urine using 2H-labeled compound and GC-MS. Rats fasted for 12 h were intragastrically given a mixture of 2H-labeled (consisting of monodeutero- and dideutero-BDD in the ratio about 1:1.3) and non-labeled BDD 150 mg/kg and placed in metabolism cages for urine collection. The 24 h urine was filtered and extracted three times each with 5 ml of methylenedichloride. The extracts were pooled and evaporated to dryness under reduced pressure at 35 degrees C. The residue was redissolved in chloroform and subjected to GC-MS analysis. The mass spectrum (m/z: 404, 405, 406; 373, 374, 375; 345, 346, 347; 330, 331, 332; etc) indicates that the molecular ionic and fragment peaks of the metabolite all have 14 amu less than those of BDD. This means that the metabolite isolated is mono-O-demethylated BDD. The result confirmed our findings reported previously.


Assuntos
Compostos de Bifenilo , Dioxóis/metabolismo , Medicamentos de Ervas Chinesas/metabolismo , Animais , Dioxóis/urina , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Ratos , Ratos Endogâmicos
10.
Yao Xue Xue Bao ; 32(8): 617-9, 1997 Aug.
Artigo em Zh | MEDLINE | ID: mdl-11596313

RESUMO

A convenient method for the quantitative analysis of adenosine and thymidine in Fritillaria bulbs was developed by means of dual wavelength ultraviolet spectrophotometry. This method has good linear relationship and the interrelated coefficient of standard curve for adenosine and thymidine were all found to be 0.9999. The methanol extracts of four species of Fritillaria have been analyzed with this method. The results show that the the bulbs of four species contain different quantities of adenosine and thymidine, which indicates that the nucleosides may be responsible for the anti-coagulation activity of Fritillaria.


Assuntos
Adenosina/análise , Medicamentos de Ervas Chinesas/química , Liliaceae/química , Plantas Medicinais/química , Timidina/análise , Medicamentos de Ervas Chinesas/classificação , Liliaceae/classificação , Plantas Medicinais/classificação , Especificidade da Espécie , Espectrofotometria Ultravioleta
11.
Yao Xue Xue Bao ; 35(11): 843-6, 2000 Nov.
Artigo em Zh | MEDLINE | ID: mdl-11218863

RESUMO

AIM: To study the metabolic chiral inversion and chiral metabolites of R-(-)-ibuprofen. METHODS: Following administration of R-(-)-ibuprofen (250 mg.kg-1), analysis was performed on rat urine purified extracts obtained by solid phase extraction onto C-18 bonded silica gel, then the metabolites of ibuprofen were detected and identified by 1HNMR spectroscopy. RESULTS: Except for a little ibuprofen, there were 2'-hydroxy-ibuprofen and its glucuronide, 1'-carboxy-ibuprofen glucuronide and ibuprofen glucuronide in rat urine. 2'-hydroxy-ibuprofen is the main metabolite. 1'-carboxy-ibuprofen glucuronide and ibuprofen glucuronide were diastereoisomers. CONCLUSION: There was the phenomenon of metabolic chiral inversion, whereby the R-enantiomer is transformed in vivo to its active S-antipode via an unusual process.


Assuntos
Anti-Inflamatórios não Esteroides/urina , Ibuprofeno/urina , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Feminino , Ibuprofeno/farmacocinética , Espectroscopia de Ressonância Magnética , Ratos , Ratos Wistar
12.
Yao Xue Xue Bao ; 30(2): 103-6, 1995.
Artigo em Zh | MEDLINE | ID: mdl-7785432

RESUMO

HH01(1-methyl-3,4,5,6,9,10-hexahydro-7H-cyclopenta [j,k]-1,3-dioxolo [4,5-h]-pyrrolo[2,1-b] [3]-benzazepine) A and B in doses 30 mg.kg-1 and 60 mg.kg-1 were shown to protect gastric mucosa of rats from damage induced by absolute ethanol, cold-immersion stress and pylorus ligation. No effect was found in indomethacin model in mice. HH01 was found to decrease secretion of gastric juice and HCl in pylorus ligated rats. The content of DNA in gastric juice of animals treated with HH01 was lower than in control. The results suggest that HH01 is effective as an anti-ulcer agent, but its mechanism of action is yet unknown.


Assuntos
Antiulcerosos/uso terapêutico , Benzazepinas/uso terapêutico , Dioxóis/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , DNA/metabolismo , Suco Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Masculino , Camundongos , Ratos , Ratos Wistar
13.
Yao Xue Xue Bao ; 31(10): 746-50, 1996.
Artigo em Zh | MEDLINE | ID: mdl-9863242

RESUMO

The effects of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E), in experimental ulcers induced by absolute alcohol, HCl, indomethacin, pyloric ligation and chronic acetic acid in rats were studied. PG6E at doses 10-80 micrograms.kg-1 was shown to have significant protective effect. PG6E (30-60 micrograms.kg-1) was also found to reduce markedly the acid secretion, pepsin activity, DNA content of the juice collected from pylorus ligated stomach of rats and increase markedly the content of gastric mucosa hexosamine in mice given PG6E (30-60 micrograms.kg-1 po for 3 d). At doses of 40-80 micrograms.kg-1, PG6E was able to have no significant effect on gastric emptying time in rats and gastrointestinal tract movement in mice. It appears that PG6E was shown to inhibit the aggressive factors and increase the protective factors of gastric mucosa. This may hopefully become a new antiulcer agent.


Assuntos
Antiulcerosos/farmacologia , Arbaprostilo/análogos & derivados , Ácido Gástrico/metabolismo , Úlcera Gástrica/metabolismo , Animais , Arbaprostilo/farmacologia , Feminino , Esvaziamento Gástrico/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Ratos , Ratos Wistar , Úlcera Gástrica/fisiopatologia
14.
Yao Xue Xue Bao ; 32(1): 79-80, 1997.
Artigo em Zh | MEDLINE | ID: mdl-11243226

RESUMO

The antisecretion effect of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E) was studied in perfusing rats in vivo. The results showed that PG6E at the dose 0.1 mg.kg-1 decreased markedly the acid secretion and antagonized the gastric acid secretion induced by histamine, pilocarpin and pentagastrin in rats. This action of PG6E appeared to be similar to that of cimetidine (40 mg.kg-1).


Assuntos
Arbaprostilo/farmacologia , Ácido Gástrico/metabolismo , Fármacos Gastrointestinais/farmacologia , Animais , Arbaprostilo/análogos & derivados , Antagonistas dos Receptores Histamínicos , Masculino , Pentagastrina/antagonistas & inibidores , Pilocarpina/antagonistas & inibidores , Ratos
17.
Proc Natl Acad Sci U S A ; 97(7): 3022-7, 2000 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-10737784

RESUMO

The splicing factor Prp18 is required for the second step of pre-mRNA splicing. We have isolated and determined the crystal structure of a large fragment of the Saccharomyces cerevisiae Prp18 that lacks the N-terminal 79 amino acids. This fragment, called Prp18Delta79, is fully active in yeast splicing in vitro and includes the sequences of Prp18 that have been evolutionarily conserved. The core structure of Prp18Delta79 is compact and globular, consisting of five alpha-helices that adopt a novel fold that we have designated the five-helix X-bundle. The structure suggests that one face of Prp18 interacts with the splicing factor Slu7, whereas the more evolutionarily conserved amino acids in Prp18 form the opposite face. The most highly conserved region of Prp18, a nearly invariant stretch of 19 aa, forms part of a loop between two alpha-helices and may interact with the U5 small nuclear ribonucleoprotein particles. The structure is consistent with a model in which Prp18 forms a bridge between Slu7 and the U5 small nuclear ribonucleoprotein particles.


Assuntos
Proteínas Fúngicas/química , Proteínas Nucleares , Proteínas de Saccharomyces cerevisiae , Sequência de Aminoácidos , Animais , Sequência Conservada , Cristalografia por Raios X , Proteínas Fúngicas/metabolismo , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Precursores de RNA/genética , RNA Mensageiro/genética , Ribonucleoproteína Nuclear Pequena U5 , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de Aminoácidos
18.
Proc Natl Acad Sci U S A ; 93(13): 6308-13, 1996 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-8692811

RESUMO

A large family of isoquinoline sulfonamide compounds inhibits protein kinases by competing with adenosine triphosphates(ATP), yet interferes little with the activity of other ATP-using enzymes such as ATPases and adenylate cyclases. One such compound, N-(2-aminoethyl)-5-chloroisoquinoline-8-sulfonamide (CK17), is selective for casein kinase-1 isolated from a variety of sources. Here we report the crystal structure of the catalytic domain of Schizosaccharomyces pombe casein kinase-1 complexed with CK17, refined to a crystallographic R-factor of 17.8% at 2.5 angstrom resolution. The structure provides new insights into the mechanism of the ATP-competing inhibition and the origin of their selectivity toward different protein kinases. Selectivity for protein kinases versus other enzymes is achieved by hydrophobic contacts and the hydrogen bond with isoquinoline ring. We propose that the hydrogen bond involving the ring nitrogen-2 atom of the isoquinoline must be preserved, but that the ring can flip depending on the chemical substituents at ring positions 5 and 8. Selectivity for individual members of the protein kinase family is achieved primarily by interactions with these substituents.


Assuntos
Inibidores Enzimáticos/farmacologia , Isoquinolinas/farmacologia , Inibidores de Proteínas Quinases , Sulfonamidas , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Cristalografia por Raios X , Inibidores Enzimáticos/química , Ligação de Hidrogênio , Isoquinolinas/química , Isoquinolinas/metabolismo , Dados de Sequência Molecular , Estrutura Molecular , Relação Estrutura-Atividade
19.
Cell ; 105(2): 269-79, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11336676

RESUMO

The SIR2 protein family comprises a novel class of nicotinamide-adenine dinucleotide (NAD)-dependent protein deacetylases that function in transcriptional silencing, DNA repair, and life-span extension in Saccharomyces cerevisiae. Two crystal structures of a SIR2 homolog from Archaeoglobus fulgidus complexed with NAD have been determined at 2.1 A and 2.4 A resolutions. The structures reveal that the protein consists of a large domain having a Rossmann fold and a small domain containing a three-stranded zinc ribbon motif. NAD is bound in a pocket between the two domains. A distinct mode of NAD binding and an unusual configuration of the zinc ribbon motif are observed. The structures also provide important insights into the catalytic mechanism of NAD-dependent protein deacetylation by this family of enzymes.


Assuntos
Proteínas Arqueais/química , Archaeoglobus fulgidus/química , Histona Desacetilases/química , NAD/química , Estrutura Terciária de Proteína , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae , Transativadores/química , Sequência de Aminoácidos , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Archaeoglobus fulgidus/genética , Sítios de Ligação , Cristalografia por Raios X , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , NAD/metabolismo , Alinhamento de Sequência , Sirtuína 2 , Sirtuínas , Transativadores/genética , Transativadores/metabolismo
20.
EMBO J ; 14(5): 1015-23, 1995 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7889932

RESUMO

The structure of a truncated variant of casein kinase-1 from Schizosaccharomyces pombe, has been determined in complex with MgATP at 2.0 A resolution. The model resembles the 'closed', ATP-bound conformations of the cyclin-dependent kinase 2 and the cAMP-dependent protein kinase, with clear differences in the structure of surface loops that impart unique features to casein kinase-1. The structure is of unphosphorylated, active conformation of casein kinase-1 and the peptide-binding site is fully accessible to substrate.


Assuntos
Modelos Moleculares , Conformação Proteica , Proteínas Quinases/química , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Caseína Quinases , Cristalografia por Raios X , Dados de Sequência Molecular , Fosforilação , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Schizosaccharomyces/enzimologia , Alinhamento de Sequência , Deleção de Sequência , Especificidade por Substrato
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