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1.
Zhonghua Er Ke Za Zhi ; 61(8): 719-725, 2023 Aug 02.
Artigo em Chinês | MEDLINE | ID: mdl-37528013

RESUMO

Objective: To investigate the risk factors for airway mucus hypersecretion in childhood pneumonia infected by different pathogens. Method: A retrospective cohort included 968 children who were hospitalized for Mycoplasma pneumoniae pneumonia (MPP), respiratory syncytial virus (RSV) pneumonia, adenovirus pneumonia and underwent bronchoscopy in Respiratory Department of Children's Hospital of Chongqing Medical University from January 2019 to December 2021 was conducted. The children were divided into two groups distinguished by airway mucus secretion according to the airway mucus hypersecretion score which were scored according to the mucus secretion under the bronchoscope. The demographic characteristics, clinical characteristics, laboratory tests and disease severity of the two groups were compared. And the risk factors for the development of airway mucus hypersecretion in two groups were analyzed. Chi square test, Mann-Whithey U test and Fisher exact test were used to analyze the differences between the two groups, and multivariate Logistic regression was used to analyze the influencing factors. Result: There were 559 males and 409 females in the 968 children, with an age of 4.0 (1.4, 6.0) years. Among the 642 children with MPP, 185 cases were in the hypersecretion group and 457 cases were in the non-hypersecretion group. There were 41 cases in the hypersecretion group and 160 cases in the non-hypersecretion group of 201 children with RSV pneumonia. In the 125 children with adenovirus pneumonia, there were 39 cases in the hypersecretion group and 86 cases in the non-hypersecretion group. In these children, the age of children in the hypersecretion group was older than that in the non-hypersecretion group (6.0 (4.0, 7.0) vs. 5.0 (3.0, 7.0) years old, 1.5 (0.5, 3.6) vs. 0.8 (0.4, 1.6) years old, 2.0 (1.2, 4.5) vs. 1.3 (0.8, 2.0) years old, U=35 295.00, 2 492.00, 1 101.00, all P<0.05). Through multivariate Logistic regression analysis it found that increased risk of airway mucus hypersecretion was present in childhood MPP with increase in peripheral blood white blood cell count (OR=3.30, 95%CI 1.51-7.93, P=0.004) or increase in neutrophil ratio (OR=2.24, 95%CI 1.16-4.33, P=0.016) or decrease in lymphocyte count (OR=3.22, 95%CI 1.66-6.31, P<0.001) or decrease in serum albumin (OR=2.00, 95%CI 1.01-3.98, P=0.047). The risk of airway mucus hypersecretion was increased in children with RSV pneumonia combined with elevated peripheral blood eosinophils (OR=3.04, 95%CI 1.02-8.93, P=0.043). Meanwhile, airway mucus hypersecretion was associated with severe pneumonia (OR=2.46, 95%CI 1.03-6.15, P=0.047) in children with RSV pneumonia. Older age was associated with increased risk of airway mucus hypersecretion in children with adenovirus pneumonia (OR=1.02, 95%CI 1.00-1.04, P=0.026). In these children with occurrence of pulmonary rales, wheezes or sputum sounds (OR=3.65, 95%CI 1.22-12.64, P=0.028) had an increased risk of airway mucus hypersecretion. Neutrophils in bronchoalveolar lavage fluid (BALF) demonstrated higher ratio in hypersecretion group from children with MPP (0.65 (0.43, 0.81) vs. 0.59 (0.34, 0.76), U=24 507.00, P<0.01), while the proportion of macrophages in BALF was lower (0.10 (0.05, 0.20) vs. 0.12 (0.06, 0.24), U=33 043.00, P<0.05). Nucleated cell count and neutrophil ratio in BALF were higher in hypersecretion group of children with RSV pneumonia (1 210 (442, 2 100)×106 vs. 490 (210, 1 510)×106/L, 0.43 (0.26, 0.62) vs. 0.30 (0.13, 0.52), U=2 043.00, 2 064.00, all P<0.05). Conclusions: The increase in peripheral blood white blood cell count, neutrophil ratio and decrease in lymphocyte count, serum albumin in children with MPP is related to the development of airway mucus hypersecretion. In children with RSV pneumonia, the abnormal increase of eosinophils in peripheral blood has relationship with hypersecretion. The appearance of lung rale, wheezing, and sputum rale are associated with airway mucus hypersecretion in children with adenovirus pneumonia. In addition, local neutrophil infiltration in the respiratory tract is closely related to the occurrence of airway mucus hypersecretion caused by Mycoplasma pneumoniae and RSV infection.


Assuntos
Pneumonia por Mycoplasma , Pneumonia Viral , Infecções por Vírus Respiratório Sincicial , Criança , Masculino , Feminino , Humanos , Lactente , Pré-Escolar , Estudos Retrospectivos , Sons Respiratórios , Pulmão , Muco , Fatores de Risco
2.
Zhonghua Er Ke Za Zhi ; 60(7): 694-699, 2022 Jul 02.
Artigo em Chinês | MEDLINE | ID: mdl-35768358

RESUMO

Objective: To investigate the effects of Streptococcus pneumoniae (Spn) colonization and the change of upper airway microbiome on the clinical manifestations in children with respiratory syncytial virus (RSV) infection. Methods: A retrospective cohort included 508 RSV-infected children with pneumonia and hospitalized in Respiratory Department of Children's Hospital of Chongqing Medical University from July 2009 to July 2018. A total of 508 cases of RSV-infected children (RSV non-sequencing group) were divided into 2 groups: children with Spn airway colonization (RSV+Spn group) and children without with Spn airway colonization (RSV group) according to the detection for virus and bacteria in nasopharyngeal aspirate, and these 2 groups were compared in terms of clinical manifestations by chi-square test in different age groups. In addition, in RSV pandemic season from November 2018 to February 2020, nasopharyngeal aspirates were collected from 20 children hospitalized in Respiratory Department of Children's Hospital of Chongqing Medical University and infected with RSV but without any positive detection of bacteria (RSV 16 S-sequencing group) and from children undergoing surgery without any sign of respiratory infection (control group). The difference of microbiome detected by 16 S RNA sequencing was compared using rank sum test between RSV 16 S-sequencing group and control group, and also between children with severe and mild pneumonia in RSV 16 S-sequencing group. Results: A total of 508 RSV non-sequencing group included 346 males and 162 females, and the visiting age was 6 (2, 12)  months. RSV group included 443 cases and RSV+Spn group included 65 cases. In the study 244 cases were aged <6 months and 264 cases were aged ≥6 months. In children aged ≥6 months of RSV non-sequencing group, the proportion of cases presenting fever over 38 ℃ and cases with severe pneumonia in RSV+Spn group were higher than those in RSV group (53.2% (25/47) vs. 34.6% (72/217), 38.3% (18/47) vs. 21.2% (46/217), χ²=5.70,6.15, both P<0.05). RSV 16 S-sequencing group included 16 males and 4 females and the visiting age was 3.0 (1.9, 8.0) months. Airway microbiome diversity in RSV 16 S-sequencing group was lower than that in control group (alpha index: 0.93 (0.42, 2.51) vs. 3.05 (2.88, 3.61), U=60.00, P=0.001). Conclusions: RSV infection is associated with the changes of the upper airway microbiome. When the balance of airway microbiome is broken and the presence of the dominant colonization of Spn follows, it may aggravate the severity of RSV infection in children aged ≥6 months.


Assuntos
Pneumonia , Infecções por Vírus Respiratório Sincicial , Infecções Respiratórias , Criança , Feminino , Humanos , Lactente , Masculino , Infecções por Vírus Respiratório Sincicial/diagnóstico , Estudos Retrospectivos , Streptococcus pneumoniae
3.
Zhonghua Yi Xue Za Zhi ; 101(36): 2878-2884, 2021 Sep 28.
Artigo em Chinês | MEDLINE | ID: mdl-34587728

RESUMO

Objective: To explore the relationship between the daily incidence of human respiratory syncytial virus (HRSV) and meteorological parameters in the main urban area of Chongqing. Methods: This study took 3 107 children hospitalized with acute lower respiratory tract infections from June 2009 to June 2019 in department of Respiratory medicine, Children's Hospital of Chongqing Medical University (CHCMU). Nasopharyngeal aspirate (NPA) was collected on the day of admission to detect HRSV and common respiratory virus; combined with the meteorological data of the main urban area of ​​Chongqing during the same period, the correlation and distribution lag nonlinear model analysis of the daily incidence of HRSV and meteorological parameters were carried out. Results: Among 3 107 children, HRSV positive accounted for 34.53% (1 073 cases), the age was 6 (3, 13) months, and males accounted for 64.31% (690 cases). The daily incidence of HRSV was negatively correlated with minimum temperature (r=-0.220, P<0.001), maximum temperature (r=-0.221, P<0.001), average temperature (r=-0.221, P<0.001) and precipitation (r=-0.052, P<0.001), and positively correlated with sunshine time (r=0.011, P<0.001) and average relative humidity (r=0.095, P<0.001). Compared with the reference temperature (20 ℃), when the lowest temperature of 6-10 ℃ lags for 4-8 d, the RR value of HRSV was 1.11-1.14, and when the lowest temperature of 5-19 ℃ lags for 5 d and 2-19 ℃ lags for 10 d, the RR values were 1.02-1.14 and 1.00-1.03. When the cumulative lag is 5, 10, 15 and 21 d, compared with the reference temperature (20 ℃), the RR (95%CI) values at the lowest temperature of 10.4 ℃ were 1.93 (1.08-3.46), 3.49 (1.64-7.45), 5.00 (2.01-12.46) and 6.69 (2.18-20.48); the RR (95%CI) values of the lowest temperature of 22.1 ℃ were 0.87 (0.77-0.98), 0.77 (0.66-0.90), 0.74 (0.62-0.89) and 0.68 (0.55-0.85). In the cumulative effect, compared with the reference temperature (20 ℃), the gender stratification showed that the maximum RR (95%CI) values of the lowest temperature for boys and girls under different lag days were 7.24 (1.84-28.51) and 2.19 (1.07-4.46), the age stratification showed that the maximum RR (95%CI) values of the lowest temperature for children<6 months old and children ≥6 months old under different lag days were 4.72 (1.05-21.23) and 11.98 (1.70-84.35). Conclusions: In the main urban area of Chongqing, the daily incidence of HRSV in children is correlated with climatic parameters. Among them, the lowest temperature has a delayed and cumulative effect on HRSV infection. 6-10 ℃ has a greater impact on the incidence of HRSV when the lag is 4-8 days. The effect has a more obvious impact on the incidence of HRSV in boys and children ≥ 6 months.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Criança , China/epidemiologia , Correlação de Dados , Feminino , Humanos , Incidência , Lactente , Masculino , Infecções por Vírus Respiratório Sincicial/epidemiologia
5.
Epidemiol Infect ; 148: e57, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32089142

RESUMO

This study aimed at comparing the factors associated with the natural progression between typical progressors (TPs) and rapid progressors (RPs) in HIV-infected individuals. A retrospective study was conducted on 2095 eligible HIV-infected individuals from 1995 to 2016 in a high-risk area of Henan Province, China. Propensity score matching was used to balance covariates, and the conditional logistic regression analyses were performed to explore the factors of natural disease progression among HIV infectors. A total of 379 pairs of RPs and TPs were matched. The standardised difference values of all covariates were less than 10%. HIV-infected individuals transmitted through sexual transmission (odds ratio (OR) 0.56, 95% confidence interval (CI) 0.36-0.85) were more likely to progress to AIDS compared with those infected through contaminated blood. Older age at diagnosis of HIV-infected individuals (OR 0.72, 95% CI 0.58-0.89) exhibited a faster progression to AIDS. HIV-infected individuals identified through a unique survey (OR 7.01, 95% CI 2.99-16.44) were less likely to progress to AIDS compared with those identified through medical institutions. HIV-infected individuals who had higher baseline CD4+T cell counts (OR 3.37, 95% CI 2.59-4.38) had a slower progression to AIDS. These findings provide evidence for natural disease progression from HIV to AIDS between TPs and RPs.


Assuntos
Progressão da Doença , Infecções por HIV , Síndrome de Imunodeficiência Adquirida/epidemiologia , Síndrome de Imunodeficiência Adquirida/patologia , Adulto , China , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos
6.
J Dairy Sci ; 102(1): 426-435, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30366615

RESUMO

MicroRNAs (miRNA) play an essential role in mammary gland development and lactation. Previous studies in cattle have shown that miR-221 is highly expressed in peak compared with early lactation. However, the functions of miR-221 in bovine mammary gland epithelial cells and the mechanisms by which this miRNA affects cell proliferation and milk synthesis remain unclear. We hypothesized that miR-221 targets and modulates the expression of specific genes in the Janus kinase-signal transducer and activator of transcription (JAK-STAT) and phosphatidylinositol 3-kinase-proteinkinase B/mammalian target of rapamycin (PI3K-Akt/mTOR) signaling pathways, which have crucial roles in lactation in cattle. Following transfection of miR-221 into cultured bovine mammary gland epithelial cells, inhibition of cell proliferation and reduced viability of these cells were observed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry analysis. To elucidate the molecular mechanisms of the effects of miR-221 on cell proliferation, we selected potential candidate genes that can be targeted by miR-221 using bioinformatics prediction tools. The dual luciferase assay revealed that STAT5a, STAT3, and IRS1 interact with miR-221 by its direct binding to the 3'-untranslated regions (UTR) of these genes. Subsequent analysis showed that transfection of a miR-221 mimic resulted in significantly decreased expression of STAT5a and IRS1 at both the RNA and protein levels using quantitative real-time PCR and Western blot analyses. Furthermore, expression levels of the downstream genes SOCS3, AKT3, and mTOR that are regulated by STAT5a and IRS1 in the JAK-STAT and PI3K-Akt/mTOR signaling pathways, were also altered after miR-221 transfection. This is the first study to reveal the mechanisms by which miR-221 inhibits mammary gland epithelial cell proliferation by targeting STAT5a and IRS1, key genes in the PI3K-Akt/mTOR and JAK-STAT signaling pathways.


Assuntos
Bovinos/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , MicroRNAs/genética , Leite/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Regiões 3' não Traduzidas/genética , Animais , Bovinos/fisiologia , Proliferação de Células , Células Epiteliais/metabolismo , Feminino , Proteínas Substratos do Receptor de Insulina/genética , Lactação , Glândulas Mamárias Animais/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/genética
7.
J Econ Entomol ; 110(6): 2364-2370, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29029204

RESUMO

The sex pheromones of Ectropis grisescens Warren and Ectropis obliqua Prout were both reported to contain (Z,Z,Z)-3,6,9-octadecatriene (Z3,Z6,Z9-18:H) and (Z,Z)-3,9-cis-6,7-epoxy-octadecadiene (Z3,epo6,Z9-18:H). To clarify how these two sibling geometrids maintain premating isolation, the female sex pheromones of the two species were reexamined. Gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography-mass spectrometry revealed two GC-EAD-active compounds, Z3,Z6,Z9-18:H and Z3,epo6,Z9-18:H, in E. grisescens female pheromone glands as well as an additional GC-EAD-active compound, (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3,epo6,Z9-19:H), in E. obliqua female pheromone glands. Synthesized Z3,Z6,Z9-18:H and Z3,epo6,Z9-18:H elicited dose-dependent electroantennogram (EAG) responses from male antennae of both E. grisescens and E. obliqua. However, Z3,epo6,Z9-19:H only elicited dose-dependent EAG responses from E. obliqua and limited EAG responses from E. grisescens at all doses. In wind-tunnel studies, lures that contained Z3,Z6,Z9-18:H and Z3,epo6,Z9-18:H attracted E. grisescens males and had no effect on E. obliqua males. The addition of Z3,epo6,Z9-19:H to the blend of Z3,Z6,Z9-18:H and Z3,epo6,Z9-18:H strongly attracted E. obliqua males but had a limited attraction for E. grisescens males. Thus, Z3,Z6,Z9-18:H and Z3,epo6,Z9-18:H were sex pheromone components of E. grisescens, whereas Z3,Z6,Z9-18:H, Z3,epo6,Z9-18:H and Z3,epo6,Z9-19:H were sex pheromone components of E. obliqua. The presence or absence of Z3,epo6,Z9-19:H played a central role in the premating isolation of these two sibling species.


Assuntos
Mariposas/fisiologia , Isolamento Reprodutivo , Atrativos Sexuais/metabolismo , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Atrativos Sexuais/análise
8.
J Econ Entomol ; 109(3): 1241-1248, 2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26842809

RESUMO

Two thrips species-the yellow tea thrips ( Scirtothrips dorsalis Hood) and the stick tea thrips ( Dendrothrips minowai Priesner)-are serious pests affecting tea plants in southern China. Although the stick tea thrips is primarily restricted to southern China, the yellow tea thrips is gradually proliferating worldwide. Colored sticky card traps may be useful for monitoring and capturing these species, but a systematic analysis has not been conducted to identify the most effective trap color, height, and orientation. We performed indoor experiments using an orthogonal experimental design, as well as field tests in tea gardens, to identify the color most attractive to the two thrips species. Field tests were then conducted using color-optimized traps-lawngreen (RGB: 124, 252, 0) for yellow thrips and lime (RGB: 0, 255, 0) for stick tea thrips-to determine the most effective trap height and orientation. The greatest numbers of both yellow and stick tea thrips were captured on traps positioned 0-20 cm above the tea canopy in an east-west orientation. We also evaluated the performance of the color-optimized sticky card traps compared with commercially available yellow ones. Significantly more yellow and stick tea thrips and fewer natural enemies were captured on the color-optimized traps than on commercial ones. Although additional research is needed to explain the responses of the two different species and to increase trap effectiveness, our findings should assist in the control of these harmful insects.

9.
Plant Dis ; 94(12): 1503, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30743366

RESUMO

Since 2006, stem and root rot of sweetpotato has been observed in fields at a number of sweetpotato-production areas in Huidong, Haifeng, Puning, and Zhanjiang counties and Guangzhou City in Guangdong Province of China. Initially, the leaves turn yellow, and a black, water-soaked rot occurs on the bottom of the stems that gradually extends to the top of the stems. Finally, the entire plant collapses and dies. Bacteria were consistently isolated from stems of diseased seedlings by streaking on nutrient agar. Twelve representative isolates were chosen for further characterization. All strains grew at 37°C, were gram negative, facultatively anaerobic, and rod shaped with peritrichous flagella. The strains were negative for oxidase and positive for catalase and tryptophanase (indole production) They fermented glucose, reduced nitrates to nitrites, degraded pectate, produced phosphatase and lecithinase, and utilized citrate, tartrate, malonate, glucose, sucrose, fructose, and maltose, but not trehalose and lactose. These characteristics were similar to those of Erwinia chrysanthemi (Pectobacterium chrysanthemi) (1). PCR was performed on the 16S rDNA gene from isolate H12 (1,503 bp; GenBank Accession No. GU252371) with primers 27f (5'-GAGAGTTTGATCCTGGCTCAG-3') and reverse primer (5'-GGCTACCTTGTTACGACTTC-3'). Subsequently, PCR products were sequenced. Results of sequence analysis showed the sequence of isolated strain H12 was 99% identical to that of E. chrysanthemi, 99% identical to that of type strain CFBP 1269T of Dickeya dadantii (Accession No. AF520707), and 98% identical to that of type strain CFBP 1200T of D. dianthicola (Accession No. AF520708). Recently, E. chrysanthemi was transferred to Dickeya gen. nov., but it was difficult to identify the species within the genus Dickeya. Seedlings (20 to 30 cm) were planted in 10-cm-diameter plastic pots containing sterilized field soil at room temperature. Four days later, five stem tops of sweetpotato were injected with a bacteria suspension (108 CFU/ml) of approximately 100 µl to fulfill Koch's postulates. Five control plants were inoculated with sterile distilled water. The experiment was conducted three times. All plants were incubated in a chamber at 30°C with high humidity. One to two days after inoculation, symptoms were observed in all inoculated plants and appeared to be identical to those observed in the field. No symptoms were noted on the control plants. The bacterium was reisolated from symptomatic stems of sweetpotato plants. This pathogen was previously reported on sweetpotato in the United States in 1974 (2). To our knowledge, this is the first report of a Dickeya sp. (E. chrysanthemi) causing bacterial stem and root rot of sweetpotato in China. References: (1) D. J. Brenner et al. Page 670 in: Bergey's Manual of Systematic Bacteriology. 2nd ed. Springer, New York, 2005. (2) N. W. Schaad et al. Phytopathology 67:302, 1977.

10.
Science ; 292(5521): 1535-40, 2001 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-11375489

RESUMO

A fossil from the Early Jurassic (Sinemurian, approximately 195 million years ago) represents a new lineage of mammaliaforms, the extinct groups more closely related to the living mammals than to nonmammaliaform cynodonts. It has an enlarged cranial cavity, but no postdentary trough on the mandible, indicating separation of the middle ear bones from the mandible. This extends the earliest record of these crucial mammalian features by some 45 million years and suggests that separation of the middle ear bones from the mandible and the expanded brain vault could be correlated. It shows that several key mammalian evolutionary innovations in the ear region, the temporomandibular joint, and the brain vault evolved incrementally through mammaliaform evolution and long before the differentiation of the living mammal groups. With an estimated body weight of only 2 grams, its coexistence with other larger mammaliaforms with similar "triconodont-like" teeth for insectivory within the same fauna suggests a great trophic diversity within the mammaliaform insectivore feeding guild, as inferred from the range of body sizes.


Assuntos
Evolução Biológica , Fósseis , Mamíferos , Vertebrados , Animais , Constituição Corporal , Peso Corporal , China , Orelha/anatomia & histologia , Ossículos da Orelha/anatomia & histologia , Mamíferos/anatomia & histologia , Mamíferos/classificação , Mandíbula/anatomia & histologia , Filogenia , Crânio/anatomia & histologia , Articulação Temporomandibular/anatomia & histologia , Vertebrados/anatomia & histologia , Vertebrados/classificação
11.
Nature ; 409(6816): 53-7, 2001 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-11343108

RESUMO

Marsupials, placentals and their close therian relatives possess complex (tribosphenic) molars that are capable of versatile occlusal functions. This functional complex is widely thought to be a key to the early diversification and evolutionary success of extant therians and their close relatives (tribosphenidans). Long thought to have arisen on northern continents, tribosphenic mammals have recently been reported from southern landmasses. The great age and advanced morphology of these new mammals has led to the alternative suggestion of a Gondwanan origin for the group. Implicit in both biogeographic hypotheses is the assumption that tribosphenic molars evolved only once in mammalian evolutionary history. Phylogenetic and morphometric analyses including these newly discovered taxa suggest a different interpretation: that mammals with tribosphenic molars are not monophyletic. Tribosphenic molars evolved independently in two ancient (holotherian) mammalian groups with different geographic distributions during the Jurassic/Early Cretaceous: an australosphenidan clade endemic to Gondwanan landmasses, survived by extant monotremes; and a boreosphenidan clade of Laurasian continents, including extant marsupials, placentals and their relatives.


Assuntos
Evolução Biológica , Mamíferos , África , Animais , Ásia , Dentição , Europa (Continente) , Fósseis , Mamíferos/anatomia & histologia , Mamíferos/classificação , Modelos Biológicos , Dente Molar/anatomia & histologia , América do Norte , Paleodontologia , Filogenia , Dente/anatomia & histologia
12.
Nature ; 398(6725): 326-30, 1999 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-10192332

RESUMO

Here we describe a new triconodont mammal from the Late Jurassic/Early Cretaceous period of Liaoning, China. This new mammal is represented by the best-preserved skeleton known so far for triconodonts which form one of the earliest Mesozoic mammalian groups with high diversity. The postcranial skeleton of this new triconodont shows a mosaic of characters, including a primitive pelvic girdle and hindlimb but a very derived pectoral girdle that is closely comparable to those of derived therians. Given the basal position of this taxon in mammalian phylogeny, its derived pectoral girdle indicates that homoplasies (similarities resulting from independent evolution among unrelated lineages) are as common in the postcranial skeleton as they are in the skull and dentition in the evolution of Mesozoic mammals. Limb structures of the new triconodont indicate that it was probably a ground-dwelling animal.


Assuntos
Evolução Biológica , Fósseis , Mamíferos , Animais , China , Mamíferos/anatomia & histologia , Mamíferos/classificação , Esqueleto
13.
Zhonghua Wai Ke Za Zhi ; 32(7): 424-6, 1994 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-7842983

RESUMO

GD-I porcine bioprosthetic valve replacement were performed in 15 cases from Jul. 1978 to Nov. 1982. Pathology: RHD 11, CHD 4, 13 with MVR, 1 AVR, 1 TVR. One patient died during operation (operative mortality 6.7%). 13 cases were followed up for 3-10 years: in the early years the symptoms and cardiac function were greatly improved and the size reduced. However dysfunction of bioprosthetic valve was detected 2-8 years after operation in 12 patients (19.37%/patient year). The main cause of damage and dysfunction of porcine valve is calcification of the leaflet. As compared with the adult group(dysfunction rate 3.6%/patient year) in this institute, more calcification of the porcine valve in children is considered because of: (1) stronger metabolism of calcium in children, (2) less mobility of the leaflet due to lower cardiac output in children, and (3) stronger immunoreaction to porcine valve in children.


Assuntos
Bioprótese , Cardiopatias Congênitas/cirurgia , Próteses Valvulares Cardíacas , Adolescente , Criança , Feminino , Seguimentos , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Cardiopatia Reumática/cirurgia
14.
Zhonghua Xin Xue Guan Bing Za Zhi ; 21(3): 155-7, 187, 1993 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-8243229

RESUMO

From March 1965 through August 1991, 703 patients with secondary atrial septal defect were treated surgically in our hospital. Among them, 32 cases (4.6%) were associated with mitral valve disease. The mitral valve lesion was repaired at the same time of closure of the atrial septal defect. The operative mortality was 6.3% and there was no late death. Follow-up study showed that heart function of the patients was improved obviously and most of them have resumed work or study. The clinical features, incidence, etiology, pathology and surgical techniques of secondary atrial septal defect associated with mitral valve disease were discussed.


Assuntos
Comunicação Interatrial/cirurgia , Insuficiência da Valva Mitral/cirurgia , Estenose da Valva Mitral/cirurgia , Adolescente , Adulto , Criança , Feminino , Seguimentos , Comunicação Interatrial/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Estenose da Valva Mitral/complicações , Insuficiência da Valva Tricúspide/complicações , Insuficiência da Valva Tricúspide/cirurgia
15.
J Biol Chem ; 264(15): 8495-8, 1989 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-2722785

RESUMO

Cooperative binding of myosin S-1.ADP to regulated F-actin was previously reported and has been interpreted by a two-state model in which an important source of cooperativity is nearest neighbor interactions between the 7-actin.tropomyosin (TM).troponin units (functional units) (Hill, T.L., Eisenberg, E., and Greene, L. (1980) Proc. Natl. Acad. Sci. U.S.A. 77, 3186-3190). It has been postulated that the head-to-tail overlap between adjacent TM molecules is the structural basis of the nearest neighbor interactions. We tested the hypothesis by examining S-1.ADP binding to reconstituted regulated F-actin containing either intact TM or nonpolymerizable TM from which the COOH-terminal 11 residues were removed. In the absence of Ca2+, substitution of nonpolymerizable TM for TM reduced significantly the slope of the steeply rising phase of the sigmoidal S-1.ADP binding curve. Nevertheless, considerable residual cooperativity remained. Analysis of the data using the two-state model of Hill et al. suggests that removal of TM overlap abolishes nearest neighbor interactions, while the concerted change of the state of 7 actins in a functional unit can account for the residual cooperativity.


Assuntos
Citoesqueleto de Actina/metabolismo , Citoesqueleto/metabolismo , Músculos/metabolismo , Miosinas/metabolismo , Fragmentos de Peptídeos/metabolismo , Tropomiosina/metabolismo , Actinas/metabolismo , Animais , Sítios de Ligação , Cálcio/farmacologia , Cinética , Masculino , Subfragmentos de Miosina , Ligação Proteica , Coelhos
17.
Zhonghua Wai Ke Za Zhi ; 25(4): 237-9, 255, 1987 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-3652883
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