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1.
Artigo em Chinês | MEDLINE | ID: mdl-38811177

RESUMO

Objective: By conducting a retrospective analysis of the clinical data of 14 patients diagnosed with invasive fungal rhinosinusitis (IFRS) confirmed by metagenomics next generation sequencing (mNGS) technology, we aim to explore the rapid diagnosis value of mNGS in IFRS. Methods: The clinical data of 14 IFRS patients admitted to TianJin First Central Hospital were retrospectively analyzed from February 2021 to October 2023. The study cohort comprised 8 males and 6 females, with ages ranging from 14 to 77 years. All patients were diagnosed as IFRS by performing mNGS sequencing technology of nasal sinus lesion biopsy specimens. Clinical data such as laboratory examination, imaging examination, histopathological examination results, treatment plan and prognosis were summarized and analyzed. Results: All 14 patients were diagnosed as IFRS, with mNGS detecting pathogens such as Rhizopus (7 cases), Aspergillus (5 cases), Trichoderma (1 case), and Scedosporium apiospermum (1 case). Follow-up evaluations were conducted for a period ranging from 2 months to 2 years post-treatment. At the end of follow-up, 11 out of 14 IFRS patients achieved a complete cure with no signs of recurrence, while the symptoms of the remaining 3 patients significantly improved with comprehensive treatment. Conclusion: mNGS emerges as a highly effective diagnostic tool for IFRS, providing valuable microbiological evidence for clinical diagnosis and demonstrating promising clinical utility.


Assuntos
Sinusite , Humanos , Masculino , Feminino , Sinusite/microbiologia , Sinusite/diagnóstico , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Adolescente , Adulto , Adulto Jovem , Metagenômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Micoses/diagnóstico , Micoses/microbiologia , Aspergillus/isolamento & purificação , Rinite/diagnóstico , Rinite/microbiologia , Rhizopus/isolamento & purificação , Scedosporium/isolamento & purificação
2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 50(3): 277-281, 2022 Mar 24.
Artigo em Chinês | MEDLINE | ID: mdl-35340147

RESUMO

Objective: To investigate the relationship between the mechanical circulatory support (MCS) combined with immunomodulation and the prognosis of patients with fulminant myocarditis. Methods: This is a retrospective study. A total of 88 patients with fulminant myocarditis admitted to Dongguan Kanghua hospital from Aug. 2008 to Dec. 2020 were included. Medical histories, results of laboratory tests, treatment regimens and clinical outcomes of these patients during their hospitalization were collected from the medical record system. According to the treatment methods, the patients were divided into MCS+immunomodulation group (38 cases), MCS group (20 cases) and traditional treatment group (30 cases). Patients in the MCS+immunomodulation group received intra-aortic balloon pump (IABP) or IABP combined with extracorporeal membrane oxygenation (ECMO) and immunoglobulin or glucocorticoid. Patients in the MCS group only received mechanical circulatory support. Patients in the traditional treatment group received neither mechanical circulatory support nor immunomodulatory therapy, and only used vasoactive drugs and cardiotonic drugs. The in-hospital mortality and length of stay were compared among the three groups. Results: A total of 88 patients with fulminant myocarditis aged (35.0±10.8) years were included, and there were 46 males (52.3%). The mortality of MCS+immunomodulation group (7.9% (3/38) vs. 56.7% (17/30), P=0.001 2) and MCS group (30.0% (6/20) vs. 56.7% (17/30), P=0.002 8) were lower than that of traditional treatment group. Compared with the MCS group, the in-hospital mortality in the MCS+immunomodulation group was lower (P=0.005 4). The most common cause of death was multiple organ dysfunction syndrome (MODS). The constituent ratios of death in MCS+immunomodulation group, MCS group and traditional treatment group were 3/3, 4/6 and 12/17, respectively. The incidence of MODS in the MCS group (20% (4/20)) and the traditional treatment group (40% (12/30)) was significantly higher than that in the MCS+immunomodulation group (7.9% (3/38)) (both P<0.01). In discharged patients, the hospitalization time of MCS+immunomodulation group was shorter than that of traditional treatment group ((13.4±5.5)d vs. (18.5±7.4)d, P<0.05) and MCS group ((13.4±5.5)d vs. (16.9±8.5)d, P<0.05). Conclusion: MCS combined with immunomodulatory therapy is associated with lower in-hospital mortality and shorter hospital stay in patients with fulminant myocarditis.


Assuntos
Coração Auxiliar , Miocardite , Adulto , Humanos , Imunomodulação , Masculino , Pessoa de Meia-Idade , Miocardite/terapia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
3.
J Nutr Health Aging ; 24(3): 325-329, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115615

RESUMO

OBJECTIVES: Lymphocytes can affect the proliferation and migration of muscle satellite cells, which may be associated with reduced muscle mass in patients with sarcopenia. The present study aimed to further enrich understandings of the changes of blood lymphocytes and explore the relationship between peripheral lymphocyte subsets and muscle mass in patients with sarcopenia. DESIGN: A cross-sectional study. SETTING: Geriatrics department of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. METHODS: Eighty-five subjects were enrolled in this study, and were divided into two groups: the sarcopenia group (n=60) and the non-sarcopenia group (n=25). The diagnosis of sarcopenia was based on the diagnostic criteria updated by the Asian Working Group for Sarcopenia (AWGS) in 2014. Complete blood count, peripheral lymphocyte subsets, and body composition of all patients were measured. RESULTS: Skeletal muscle mass index (SMI) was negatively correlated with CD4+CD28null T lymphocytes in peripheral blood in patients with sarcopenia. CONCLUSION: The result of our study may point out the role of CD4+CD28null T lymphocytes in the pathogenesis of sarcopenia.


Assuntos
Subpopulações de Linfócitos/metabolismo , Músculo Esquelético/fisiologia , Sarcopenia/diagnóstico , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Dairy Sci ; 102(5): 4662-4673, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30879805

RESUMO

Accumulating studies have suggested that microRNA play a part in regulating multiple cellular processes, such as cell proliferation, apoptosis, the cell cycle, and embryo development. This study explored the effects of miR-101-2 on donor cell physiological status and the development of Holstein cow somatic cell nuclear transfer (SCNT) embryos in vitro. Holstein cow bovine fetal fibroblasts (BFF) overexpressing miR-101-2 were used as donor cells to perform SCNT; then, cleavage rate, blastocyst rate, inner cell mass-to-trophectoderm ratio, and the expression of some development- and apoptosis-related genes in different groups were analyzed. The miR-101-2 suppressed the expression of inhibitor of growth protein 3 (ING3) at mRNA and protein levels, expedited cell proliferation, and decreased apoptosis in BFF, suggesting that ING3, a target gene of miR-101-2, is a potential player in this process. Moreover, by utilizing donor cells overexpressing miR-101-2, the development of bovine SCNT embryos in vitro was significantly enhanced; the apoptotic rate in SCNT blastocysts was reduced, and the inner cell mass-to-trophectoderm ratio and SOX2, POU5F1, and BCL2L1 expression significantly increased, whereas BAX and ING3 expression decreased. Collectively, these findings suggest that miR-101-2 promotes BFF proliferation and vitality, reduces their apoptosis, and improves the early development of SCNT embryos.


Assuntos
Apoptose/genética , Bovinos/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica/genética , MicroRNAs/metabolismo , Animais , Blastocisto/metabolismo , Bovinos/crescimento & desenvolvimento , Linhagem Celular , Proliferação de Células/genética , Feminino , Fibroblastos/metabolismo , MicroRNAs/genética , Técnicas de Transferência Nuclear/veterinária , RNA Mensageiro/metabolismo
5.
Anim Reprod Sci ; 200: 14-21, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30472065

RESUMO

In this study, trehalose was investigated for its cryoprotective effects on ovarian granulosa cells (bGCs) of cattle. Five concentrations of trehalose at 0, 0.2, 0.4, 0.6 and 0.8 mol/L were added to the cryopreservation medium of bGCs, and the effects on the quality of frozen-thawed bGCs were assessed. The results indicate that the use of cryopreservation medium containing 0.2 and 0.4 mol/L of trehalose resulted in a greater rate of bGC viability compared to those of other groups (P<0.05). Culturing with trehalose at 0.2 and 0.4 mol/L increased 17ß- estradiol (E2)and decreased progesterone (P4)production (P < 0.05) in post-thawed bGCs. Compared with the control group, the intracellular Ca2+ concentrations of frozen-thawed bGCs were less in all treatment groups (P<0.05), and the least Ca2+ concentration was observed in the group containing 0.4 mol/L trehalose. The plasma membrane potentials of frozen-thawed bGCs were greater in the groups with 0.2 and 0.4 mol/L trehalose, and the group treated with 0.4 mol/L trehalose had the greatest membrane potential in comparison to other groups (P < 0.05). The relative abundance of the CYP19 mRNA in frozen-thawed bGCs was greater in the groups containing 0.2, 0.4 and 0.6 mol/L trehalose, and relative abundances of FSHR and BCL2 mRNA were greater in the group of bGCs treated with 0.2 mol/L trehalose (P<0.05). Trehalose treatment at 0.4, 0.6 and 0.8 mol/L had an inhibitory effect on BAX gene transcription in frozen-thawed bGCs (P<0.05). In summary, trehalose exhibited a greater cryoprotective effect on bGCs than basic cryopreservation medium.


Assuntos
Bovinos , Criopreservação , Crioprotetores/farmacologia , Células da Granulosa , Ovário , Trealose/farmacologia , Animais , Células Cultivadas , Criopreservação/veterinária , Citoproteção/efeitos dos fármacos , Feminino , Congelamento , Ovário/efeitos dos fármacos
6.
Zhonghua Zhong Liu Za Zhi ; 40(10): 729-735, 2018 Oct 23.
Artigo em Chinês | MEDLINE | ID: mdl-30392336

RESUMO

The development of cervical cancer is associated with persistent infection of high-risk human papillomavirus. The detection and genotyping of HPV could be used to evaluate the epidemiology of HPV infections, monitor HPV vaccine efficacy, and screen cervical cancer. There are a lot of commercially available molecular tests for HPV, based on different methodologies and detection systems. In principle, it mainly includes two categories, namely signal amplification and target amplification. Most of them are based on PCR amplification, such as fluorescent PCR, PCR-reverse hybridization, etc. The performances of detection reagents are different. In addition, HPV genotyping assays based on next-generation sequencing and quantitative HPV detection kits are developed. However, only a small number of commercial assays have been clinically verified. A large number of assays which may bring greater values in the screening of cervical cancer are needed to be clinically validated.


Assuntos
Genótipo , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/virologia , Feminino , Humanos , Programas de Rastreamento , Papillomaviridae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/diagnóstico
7.
Zhonghua Jie He He Hu Xi Za Zhi ; 41(6): 485-490, 2018 Jun 12.
Artigo em Chinês | MEDLINE | ID: mdl-29886624

RESUMO

Objective: By evaluating the hemodynamic parameters such as cardiac output (CO), right ventricular pressure (RVP), pulmonary artery pressure (PAP) and total pulmonary resistance index (TPRI) in pulmonary hypertension rat model, we established a more comprehensive hemodynamic evaluation system, which objectively evaluated the severity of disease and exercise tolerance in rats with pulmonary hypertension. Methods: SD rats were randomly divided into a control group and a model group with 5 rats in each group. The model group was intraperitoneally injected with SU5416 (20 mg/kg) and placed in an oxygen chamber at a 10% oxygen concentration for 21 days and then placed in a normoxic environment for 14 days. After modeling, rats were anesthetized and mechanically ventilated. The operator cut the skin along the right paraxial line, detached and ligated the intercostal artery, and then cut off the 3 and 4 ribs, exposing the heart and freeing aortic root about 0.2 cm. The flowmeter probe was set in the dissected aortic segment, and real-time recording time, blood flow waveforms, cardiac output were calculated accordingly. Then the needle attached to the baroreceptor was inserted into the right ventricle and the system acquired the right ventricular time-pressure waveform. After the waveform stabilized for about 30 seconds, the end of the cannula was sent to the pulmonary artery trunk through the entrance of the pulmonary artery to record the time-pressure curve of the pulmonary artery. Results: RVSP, PASP, PADP and mPAP in the model group were significantly higher than those of the control group [ RVSP(23.4±5.4) mmHg, 1 mmHg=0.133 kPa vs (56.4±13.0) mmHg, PASP (22.8±4.4) mmHg vs (58.5±14.9) mmHg, PADP (9.7±1.9) mmHg vs (30.3±7.0) mmHg, mPAP (14.1±2.7) mmHg vs (41.9±8.0) mmHg, all P<0.05 ]. Compared with the control group, the cardiac index in the model group was significantly lower [ CI (0.54±0.08) ml·min(-1)·g(-1) vs (0.40±0.09) ml·min(-1)·g(-1,) P=0.02 ]. Furthermore, compared with the control group, pulmonary vascular resistance index was significantly increased in the model group[PVRI (0.27±0.03) mmHg·ml(-1)·min(-1)·kg(-1) vs (0.06±0.01) mmHg·ml(-1)·min(-1)·kg(-1,) P<0.05]. The pathological results also showed that the middle part of pulmonary arterioles in the model group had muscular hypertrophy and muscular pulmonary arterioles, and even plexiform lesions. Conclusion: In this study, we established a new method that simultaneously determined several hemodynamic parameters such as RVSP, PASP, PADP, CO, CI and PVRI, which provided a more comprehensive assessment of hemodynamic changes in pulmonary hypertension rat models.


Assuntos
Hemodinâmica , Hipertensão Pulmonar , Animais , Frequência Cardíaca , Ventrículos do Coração , Artéria Pulmonar , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
8.
Neuroscience ; 379: 152-166, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29559385

RESUMO

Oxidative stress exhibits a central role in the course of amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative disease commonly found to include a copper/zinc superoxide dismutase (SOD1) gene mutation. Fisetin, a natural antioxidant, has shown benefits in varied neurodegenerative diseases. The possible effect of fisetin in ALS has not been clarified as of yet. We investigated whether fisetin affected mutant hSOD1 ALS models. Three different hSOD1-related mutant models were used: Drosophila expressing mutant hSOD1G85R, hSOD1G93A NSC34 cells, and transgenic mice. Fisetin treatment provided neuroprotection as demonstrated by an improved survival rate, attenuated motor impairment, reduced ROS damage and regulated redox homeostasis compared with those in controls. Furthermore, fisetin increased the expression of phosphorylated ERK and upregulated antioxidant factors, which were reversed by MEK/ERK inhibition. Finally, fisetin reduced the levels of both mutant and wild-type hSOD1 in vivo and in vitro, as well as the levels of detergent-insoluble hSOD1 proteins. The results indicate that fisetin protects cells from ROS damage and improves the pathological behaviors caused by oxidative stress in disease models related to SOD1 gene mutations probably by activating ERK, thereby providing a potential treatment for ALS.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Antioxidantes/farmacologia , Flavonoides/farmacologia , Fármacos Neuroprotetores/farmacologia , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Animais Geneticamente Modificados , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Drosophila melanogaster , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Flavonóis , Radicais Livres/metabolismo , Humanos , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Mutação , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
9.
Zhonghua Jie He He Hu Xi Za Zhi ; 40(2): 81-85, 2017 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-28209036

RESUMO

Objective: To establish a method of isolation and primary culture of mice distal pulmonary artery smooth muscle cells (PASMCs) and identify the functional properties. Methods: PASMCs were harvested from the distal pulmonary artery (PA) tissue of mice by enzymatic digestion of collagenaseⅠand papain; and the growth characteristics were observed under inverted microscope and identified by Immunofluorescence technique. Effects on the intracellular calcium ion concentration of distal PASMCs were detected by Fura-2-AM fluorescent probe tracer under a fluorescence microscope in Krebs solution containing clopiazonic acid (CPA) and nifedipin (Nif). Results: PASMCs density reached approximately to 80% in a typical valley-peak-like shape after 6 days. Cell α-smooth muscle actin (α-SMA) immunofluorescence identified that 95% of the cultured cells were PASMCs. More than 95% PASMCs responded well to calcium-potassium Krebs solution (potassium ion concentration of 60 mmol/L) and showed a rapid increase in basal [Ca(2+) ](i) after 1 minute's perfusion (Δ[Ca(2+) ](i)>50), which demonstrated that the voltage-dependent calcium channels (VDCC) of distal PASMCs were in good function; after the perfusion of calcium Krebs, calcium-free/calcium-Krebs containing CPA and Nif, distal PASMCs showed two typical peaks, indicated the full function of store-operated calcium channel (SOCC) in distal PASMCs. Conclusion: This experiment successfully established a stable and reliable mice distal PASMCs model and the study of pulmonary vascular diseases could benefit from its higher purity and better functional condition.


Assuntos
Canais de Cálcio , Células Cultivadas , Miócitos de Músculo Liso , Artéria Pulmonar/fisiologia , Animais , Cálcio/análise , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Fura-2/análogos & derivados , Masculino , Camundongos , Músculo Liso Vascular , Artéria Pulmonar/metabolismo
10.
Indian J Pharm Sci ; 75(3): 357-61, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-24082353

RESUMO

Puerarin injection has been widely used for clinic treatment of diabetes recently. To assess the relationship between the administration time of puerarin and the blood concentration of puerarin as well as its pharmacokinetic parameters, the diabetic rat model was used in current study. The rats were randomly divided into morning and evening groups according to the administration time. After the puerarin injection, blood glucose was tested in order to know whether the efficiency of puerarin was influenced by its concentration and pharmacokinetic parameters. Our results show that the average concentration of puerarin in the evening group is significantly higher than that in the morning group. The numbers of t1/2α, t1/2ß, CL and AUC(0-∞) are significantly different between the morning and evening groups. The blood glucose level in the evening group was lower than that in the morning group. The speed of its onset is higher and the blood glucose level declines much more significantly in the evening group. These findings suggest that the concentration and pharmacokinetic parameters of puerarin affect its efficiency in diabetic rats. Therefore, it might be better to give puerarin in evening than in the morning for the mellitus treatment.

11.
J Int Med Res ; 40(2): 507-16, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22613411

RESUMO

OBJECTIVES: The role and clinical significance of fragile histidine triad (FHIT) gene in the pathogenesis of bladder urothelial carcinoma (UC) and the potential of Fhit protein as a prognostic biomarker for UC were investigated. METHODS: FHIT expression was determined according to semiquantitative immunohistochemical staining for Fhit protein levels in normal bladder and bladder UC tissues. Associations between FHIT expression, clinicopathological features and survival were evaluated. RESULTS: This study evaluated 42 cases of normal bladder and 125 cases of bladder UC; bladder UC cases had a median follow-up of 53.5 months. Immuno histochemistry showed that 95.2% of normal cases and 47.2% of bladder UC cases, respectively, were positive for Fhit protein; this difference was statistically significant. There was a significant association between negative FHIT expression in bladder UC and advanced tumour stage, high pathological grade, large tumour size, tumour recurrence and reduced survival time, but no association with age, gender, tumour number or tumour shape. CONCLUSIONS: The FHIT gene may have an important role in the pathogenesis of bladder UC and was expressed at lower levels in bladder UC compared with normal bladder tissue. Using Fhit protein as a biomarker could provide important information about patient prognosis.


Assuntos
Hidrolases Anidrido Ácido/genética , Proteínas de Neoplasias/genética , Neoplasias Uretrais/mortalidade , Neoplasias da Bexiga Urinária/genética , Hidrolases Anidrido Ácido/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Prognóstico , Regiões Promotoras Genéticas , Estudos Retrospectivos , Neoplasias Uretrais/genética , Neoplasias Uretrais/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade
12.
J Biomol Struct Dyn ; 26(1): 1-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18533721

RESUMO

Ultraconserved elements, sequences with 100% identity with no insertions or deletions between genomes, have been found in both vertebrate and invertebrate genomes; whether plant genomes contain ultraconserved elements, however, is unknown. We consequently compared the genomes of Arabidopsis thaliana and rice, which diverged about 200 million years ago, and identified 25 ultraconserved elements that are longer than 100 bp. Similar to those previously found, ultraconserved elements in plants tend to occur in clusters and locate at noncoding regions; nevertheless, they have many distinct features. For instance, the longest ultraconserved element between the 2 plant genomes is 1491 bp, much longer than the longest one (779 bp) between the human and rodent genomes. Some biological implications are discussed, but the functions of these plant ultraconserved elements and the reasons why they are practically frozen during the evolution of millions of years remain a mystery.


Assuntos
Arabidopsis/genética , Sequência Conservada/genética , Genoma de Planta , Oryza/genética , Mapeamento Cromossômico , Cromossomos de Plantas , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas
13.
J Biomol Struct Dyn ; 19(2): 333-41, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11697737

RESUMO

The base composition of a DNA fragment or genome is usually measured by the proportion of A+T or G+C in the sequence. The G+C content along genomic sequences is usually calculated using an overlapping or non-overlapping sliding window method. The result and accuracy of such an approach depends on the size of the window and the moving distance adopted. In this paper, a novel windowless technique to calculate the G+C content of genomic sequences is proposed. By this method, the G+C content can be calculated at different "resolution". In an extreme case, the G+C content may be computed at a specific point, rather than in a window of finite size. This is particularly useful to analyze the fine variation of base composition along genomic sequences. As the first example, the variation of G+C content along each of 16 yeast chromosomes is analyzed. The G+C-rich regions with length larger than 5 kb sequences are detected and listed in details. It is found that each chromosome consists of several G+C-rich and G+C-poor regions alternatively, i.e., a mosaic structure. Another example is to analyze the G+C content for each of the two chromosomes of the Vibrio cholerae genome. Based on the variations of the G+C content in each chromosome, it is shown that some fragments in the Vibrio cholerae genome may have been transferred from other species. Especially, the position and size of the large integron island on the smaller chromosome was precisely predicted. This method would be a useful tool for analyzing genomic sequences.


Assuntos
Composição de Bases , DNA/química , DNA/genética , Cromossomos Bacterianos/genética , Cromossomos Fúngicos/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Fúngico/química , DNA Fúngico/genética , Técnicas Genéticas , Genoma , Genoma Bacteriano , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Vibrio cholerae/química , Vibrio cholerae/genética
14.
Eur J Biochem ; 268(15): 4261-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11488920

RESUMO

The published sequence of the Vibrio cholerae genome indicates that, in addition to the genes that encode proteins of known and unknown function, there are 1577 ORFs identified as conserved hypothetical or hypothetical gene candidates. Because the annotation is not 100% accurate, it is not known which of the 1577 ORFs are true protein-coding genes. In this paper, an algorithm based on the Z curve method, with sensitivity, specificity and accuracy greater than 98%, is used to solve this problem. Twenty-fold cross-validation tests show that the accuracy of the algorithm is 98.8%. A detailed discussion of the mechanism of the algorithm is also presented. It was found that 172 of the 1577 ORFs are unlikely to be protein-coding genes. The number of protein-coding genes in the V. cholerae genome was re-estimated and found to be approximately 3716. This result should be of use in microarray analysis of gene expression in the genome, because the cost of preparing chips may be somewhat decreased. A computer program was written to calculate a coding score called VCZ for gene identification in the genome. Coding/noncoding is simply determined by VCZ > 0/VCZ < 0. The program is freely available on request for academic use.


Assuntos
Genoma de Planta , Fases de Leitura Aberta , Vibrio cholerae/genética , Algoritmos , Códon , Bases de Dados Factuais , Modelos Teóricos , Análise de Sequência com Séries de Oligonucleotídeos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Phys Rev Lett ; 87(6): 062502, 2001 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-11497825

RESUMO

Prompt and delayed gamma-ray cascades in doubly magic 132Sn and its neighbor 131Sn have been studied at Gammasphere using a 248Cm fission source. Isotopic assignments of unknown gamma rays were based on coincidences with known transitions in A = 112-116 Pd fission partners. The yrast level spectra of both tin nuclei are interpreted using empirical nucleon-nucleon interactions from the 132Sn and 208Pb regions. Results include identification of the (nuf(7/2)h(-1)(11/2))9(+) aligned state in 132Sn and of extensive (nuf(7/2)h(-2)(11/2)), (nuf(7/2)d(-1)(3/2)h(-1)(11/2)) and (nuh(-1)(11/2)x3(-)) multiplets in 131Sn. The previously reported beta(-) decay of an unusual 131In high-spin isomer to levels in 131Sn is also elucidated.

16.
J Biomol Struct Dyn ; 18(6): 872-80, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11444375

RESUMO

The codon usage in the Vibrio cholerae genome is analyzed in this paper. Although there are much more genes on the chromosome 1 than on chromosome 2, the codon usage patterns of genes on the two chromosomes are quite similar, indicating that the two chromosomes may have coexisted in the same cell for a very long history. Unlike the base frequency pattern observed in other genomes, the G+C content at the third codon position of the V. cholerae genome varies in a rather small interval. The most notable feature of codon usage of V. cholerae genome is that there is a fraction of genes show significant bias in base choice at the second codon position. The 2,006 known genes can be classified into two clusters according to the base frequencies at this position. The smaller cluster contains 227 genes, most of which code for proteins involved in transport and binding functions. The encoding products of these genes have significant bias in amino acids composition as compared with other genes. The codon usage patterns for the 1,836 function unknown ORFs are also analyzed, which is useful to study their functions.


Assuntos
Códon , DNA Bacteriano/genética , Genoma Bacteriano , Vibrio cholerae/genética , Aminoácidos/análise , Proteínas de Bactérias/química , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Composição de Bases , Cromossomos Bacterianos/genética , Genes Bacterianos , Fases de Leitura Aberta
17.
Proteins ; 43(4): 520-2, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11340667

RESUMO

Nowadays even a 1% increase of the accuracy for the secondary structure prediction is considered remarkable progress. In this case, we have to consider the reasonableness of the accuracy index Q3, which is used widely. A refined accuracy index, called Q8, is proposed to evaluate algorithms of secondary structure prediction. It is shown that Q8 is superior to the widely used index Q3 in that the former carries more information of the predictive accuracy matrix than does the latter. Therefore, algorithms are evaluated more objectively by Q8 than Q3. Based on 396 nonhomologous proteins, five currently available algorithms of secondary structure prediction were evaluated and compared using the new index Q8. Of the five algorithms, PHD turned out to be the unique algorithm, with Q8 accuracy better than 70%. It is suggested that Q3 should be replaced by Q8 in evaluating secondary structure prediction in future studies.


Assuntos
Algoritmos , Estrutura Secundária de Proteína , Valor Preditivo dos Testes
18.
Int J Biol Macromol ; 28(3): 255-61, 2001 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-11251233

RESUMO

An algorithm of predicting the subcellular location of prokaryotic proteins is proposed in this paper. In addition to the amino acid composition, the auto-correlation functions based on the hydrophobicity profile of amino acids along the primary sequence of the query protein have been used. Consequently, the best predictive accuracy to date has been achieved. Of the 997 prokaryotic proteins in the database used here, 688 cytoplasmic, 107 extracellular and 202 periplasmic proteins, the overall predictive accuracies are as high as 97.7 and 90.4% in the resubstitution and jackknife tests, respectively, using the hydrophilicity value of Hopp and Woods. The underlying mechanism of the improvement is also discussed. This work would be useful for a systematic analysis of the great amounts of prokaryotic genome sequences. The computer programs used in this paper are available on request via email.


Assuntos
Algoritmos , Aminoácidos/química , Proteínas/química , Proteínas/metabolismo , Aminoácidos/análise , Gráficos por Computador , Valor Preditivo dos Testes , Validação de Programas de Computador , Frações Subcelulares
19.
J Theor Biol ; 208(1): 65-78, 2001 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-11162053

RESUMO

An improved multiple linear regression method has been proposed to predict the content of alpha-helix and beta-strand of a globular protein based on its primary sequence and structural class. The amino acid composition and the auto-correlation functions derived from the hydrophobicity profile of the primary sequence have been taken into account. However, only the compositions of a part of the amino acids and a part of the auto-correlation functions are selected as the regression terms, which lead to the least prediction error. The resubstitution test shows that the average absolute errors are 0.052 and 0.047 with the standard deviations 0.050 and 0.047 for the prediction of helix/strand content, respectively. A rigorous cross-validation test, the jackknife test shows that the average absolute errors are 0.058 and 0.053 with the standard deviations 0.057 and 0.053 for the prediction of helix/strand content, respectively. Both tests indicate the self-consistency and the extrapolating effectiveness of the new method. The high prediction accuracy means that the method is suitable for practical applications.


Assuntos
Modelos Lineares , Estrutura Secundária de Proteína , Proteínas/química , Sequência de Aminoácidos , Animais , Dados de Sequência Molecular , Valor Preditivo dos Testes , Proteínas/genética
20.
J Protein Chem ; 19(4): 269-75, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-11043931

RESUMO

A new algorithm to predict the types of membrane proteins is proposed. Besides the amino acid composition of the query protein, the information within the amino acid sequence is taken into account. A formulation of the autocorrelation functions based on the hydrophobicity index of the 20 amino acids is adopted. The overall predictive accuracy is remarkably increased for the database of 2054 membrane proteins studied here. An improvement of about 13% in the resubstitution test and 8% in the jackknife test is achieved compared with those of algorithms based merely on the amino acid composition. Consequently, overall predictive accuracy is as high as 94% and 82% for the resubstitution and jackknife tests, respectively, for the prediction of the five types. Since the proposed algorithm is based on more parameters than those in the amino acid composition approach, the predictive accuracy would be further increased for a larger and more class-balanced database. The present algorithm should be useful in the determination of the types and functions of new membrane proteins. The computer program is available on request.


Assuntos
Aminoácidos/química , Proteínas de Membrana/química , Algoritmos
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