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1.
Environ Dev Sustain ; 25(3): 2079-2104, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35125938

RESUMO

Urban innovation and development are a core driver for promoting the industrial, economic, and social development of cities. However, the factors that affect the innovation and development of cities lack systematic analysis as well as interaction analysis. Based on a multidimensional perspective, this study suggests that natural, economic, and social factors are three major factors conditioning urban innovation and development. A grounded theoretical qualitative method is further adopted to code relevant research literatures, news reports and interview materials, resulting in an onion factors model. We find that natural factors-including environmental quality, geographic location, and city scale-are prerequisite for conditioning urban innovation and development. Economic factors are also key, including economic level, industrial structure, industrial agglomeration, and technological innovation. Social factors are guarantee factors, including administrative hierarchy, cultural environment, population structure, and government management and services, i.e., they are essential for cities to become adaptable in the current dynamic situation. The study provides theoretical support and practical directions for the formulation of policies for urban innovation development.

2.
Zhongguo Zhong Yao Za Zhi ; 45(14): 3282-3291, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32726041

RESUMO

This study is a randomized controlled trial of Reyanning Mixture in the treatment of acute tonsillitis. According to the ratio of 1∶1∶1, a total of 144 patients were randomly divided into Reyanning Mixture group(RYN), Reyanning Mixture+Amoxicillin Capsules group(RYN+Amoxil) and Amoxicillin Capsules group(Amoxil), with 48 cases in each group, in order to evaluate the efficacy and safety of RYN alone or combined with Amoxil in the treatment of acute tonsillitis, and provided high-quality evidences for treatment of infectious diseases with traditional Chinese medicine and reduced use of antibiotics. The dosage of RYN was 20 mL, 3 times a day, 100 mL/bottle, oral for 7 days, and Amoxil dosage was 0.5 g, 3 times a day, 0.5 g×12 tablets/plate, oral for 7 days. A total of 144 cases were included, 3 cases were excluded(1 case was mistakenly included, 2 cases did not take drugs after inclu-ded), and a total of 141 cases were included in the full analysis set(FAS). The results showed statistical differences in the recovery time of the disease, the disappearance rate of fever on the 3 rd day and the disappearance rate of tonsillar redness and swelling between RYN and Amoxil. There were statistical differences in the cure rate of disease, recovery time of disease, body temperature recovery time, fever disappearance rate on the 3 rd day, pharynx swelling and pain disappearance rate and tonsil swelling disappearance rate between the RYN+Amoxil and Amoxil, but with no significant difference in the above aspects compared with RYN. The DDD of antibiotic use in RYN+Amoxil was significantly lower than that in Amoxil(P<0.01). According to the findings, when RYN was used alone in the treatment of acute tonsillitis, it was superior to Amoxil in time of recovery, short-term improvement of fever and redness and swelling of tonsil. Compared with RYN+Amoxil, there was no difference in cure rate of disease, recovery time of disease, body temperature recovery time, short-term improvement of fever, swelling of pharynx and swelling of tonsil, with a better efficacy than Amoxil. The clinical effect of RYN was similar to that of combined Amoxil in the treatment of acute tonsillitis, and RYN was superior to Amoxil in the time of recovery, short-term improvement of fever and redness and swelling of tonsil, with no adverse event or adverse reaction. RYN+Amoxil can significantly reduce the DDD value of antibiotics in the treatment of acute tonsillitis, with significant clinical advantages over Amoxil.


Assuntos
Medicamentos de Ervas Chinesas , Tonsilite/tratamento farmacológico , Antibacterianos/uso terapêutico , Método Duplo-Cego , Febre/tratamento farmacológico , Humanos
3.
Bioorg Med Chem ; 27(1): 133-143, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30482547

RESUMO

A novel scaffold of arylpiperazine derivatives was discovered as potent androgen receptor (AR) antagonist through rational drug designation based on our pre-work, leading to the discovery of a series of new antiproliferative compounds. Compounds 10, 16, 27, 29 and 31 exhibited relatively strong antagonistic potency against AR and exhibited potent AR binding affinities, while compounds 5, 6, 10, 14, 16, 19, 21, 27 and 31 exhibited strong cytotoxic activities against LNCaP cells (AR-rich) as well as also displayed the higher activities than finasteride toward PC-3 (AR-deficient) and DU145 (AR-deficient). Docking study suggested that the most potent antagonist 16 mainly bind to AR ligand binding pocket (LBP) site through hydrogen bonding interactions. The structure-activity relationship (SAR) of these designed arylpiperazine derivatives was rationally explored and discussed. These results indicated that the novel scaffold compounds demonstrated a step towards the development of novel and improved AR antagonists, and promising candidates for future development were identified.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Piperazinas/farmacologia , Antagonistas de Receptores de Andrógenos/síntese química , Antagonistas de Receptores de Andrógenos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Relação Estrutura-Atividade
4.
Artigo em Chinês | MEDLINE | ID: mdl-30141871

RESUMO

Objective: To investigate the prevalence of echinococcosis in Yushu Prefecture of Qinghai Province in 2012. Methods: Two to three towns were selected in each of Chengduo, Nangqian, Qu malai, Yushu, Zaduo and Zhiduo Counties from June to August in 2012. Ultrasound examination was conducted for residents aged over 1 year, and ELISA was performed to detect serum antibody against Echinococcus. Visceral dissection was performed to detect hydatid infection in rodents and livestock. ELISA was used to detect Echinococcus antigen in collected dog feces. Results: A total of 7 025 residents received ultrasound examination, of whom 319 showed hydatid cysts with a morbidity rate of 4.54%. ELISA showed a serum antibody positive rate of 16.38% (457/2 790). The mobidity of hydatid disease was highest in Chengduo County (7.41%, 181/2 444), and the rate of serum antibody was highest in Yushu County (23.18%, 127/548). The morbidity and serum antibody in males were 3.91% (118/3 018) and 13.93% (172/1 235) respectively, and those in females were 5.02% (201/4 007) and 18.33% (285/1 555). In terms of age distribution, the morbidity was relatively higher in residents of 60- (8.39%, 38/453) and 40- years (6.61%, 67/1 014); and the rate of serum antibody was highest in residents over 70 years (33.93%, 19/56). In terms of occupation, the morbidity was relatively higher in herdsmen (5.28%, 252/4 777), Herdsmen-peasants (6.52%, 24/368), and religious workers(3.37%, 11/326), while the rate of serum antibody was relatively higher in children(24%, 6/25), religious workers (18.79%, 31/165) and herdsmen(18.34%, 328/1 788). In terms of education level, the morbidity and the rate of serum antibody were both highest in the uneducated(5.04%, 41/4 779; 18.34%, 359/1 958, respectively). In terms of residential pattern, the morbidity and the rate of serum antibody were both highest in those who were settled in winter and nomadic in summer (8.25%, 227/2 753; 19.48%, 158/811, respectively). There were significant differences in the morbidity and the rate of serum antibody in aspects of residential region, sex, age, occupation, education level and residential pattern (P<0.05 or P<0.01). In 872 rodents detected, the Echinococcus hydatid rate was 0.46% (4/872), while in 809 cattle and sheep detected, the Echinococcus hydatid rate was 10.14% (82/809). The fecal antigen positive rate in 838 samples of dog feces was 10.74%(90/838). Conclusion: It shows a high morbidity of hydatid diesease and serum antibody positive rate in residents, a high Echinococcus hydatid rate in cattle and sheep, and a high fecal antigen positive rate in dogs in Yushu Prefecture.


Assuntos
Equinococose , Echinococcus , Adulto , Distribuição por Idade , Idoso , Animais , Antígenos de Helmintos , Bovinos , Meio Ambiente , Ensaio de Imunoadsorção Enzimática , Fezes , Feminino , Humanos , Lactente , Gado , Prevalência , Estações do Ano , Ovinos , Inquéritos e Questionários , Ultrassonografia
5.
Artigo em Chinês | MEDLINE | ID: mdl-26672216

RESUMO

OBJECTIVE: To understand the status of echinococcosis in Maqing County of Qinghai Province in order to facilitate echinococcosis control in this region. METHODS: Ultrasonic scanning and indirect hemagglutination assay were used to detect echinococcosis infection in residents >1 year old, according to the People's Republic of China Health Industry Standard--Diagnostic Criteria for Hydatid Disease (WS257-2006). Meanwhile, ELISA was used o detect the Echinococcus antigen in dog's feces collected in Youyun, Dangluo and Xiadawu townships. RESULTS: Ultrasonic scanning showed that the prevalence of hydatid disease in the residents was 7.4% (116/1 561), cystic hydatid disease 5.3% (82/1 561), alveolar hydatid disease 2.2% (34/1 561). The serum positive rate in human population was 23.8%(307/1 288). Of the 82 cases of cystic hydatid disease, 23 cases (28.1%) had the hydatid cyst with a diameter of >10 cm. The prevalence in males and females in the county was 5.3% (40/753) and 9.4% (76/808), respectively (P<0.05). Among populations with different occupations, the highest prevalence of hydatid disease fell into houseworkers (11/61, 18.0%), monks (5/41, 12.2%) and herdsmen (84/758, 11.1%). Among the age groups, the groups of >60 years (24/132, 18.2%) and 30-40 years (31/302, 10.3%) had higher prevalence of hydatid disease. The three townships with the higher prevalence were Youyun (29/247, 11.7%), Changmahe (6/63, 9.5%) and Dangluo (54/645, 8.4%). Of the 199 samples of dog's feces, 54 were positive for Echinococcus antigens (27.1%), with a positive rate of 40.4% (23/57) in Youyun towship, being significantly higher than in the other two (P<0.05). CONCLUSION: Maqin county is a co-endemic area of cystic echinococcosis and alveolar echinococcosis. The prevalence is higher in females and those over 60 years-old.


Assuntos
Equinococose , Echinococcus , Animais , China , Cães , Ensaio de Imunoadsorção Enzimática , Fezes , Feminino , Testes de Hemaglutinação , Humanos , Lactente , Masculino , Prevalência
6.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2820-2826, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37897290

RESUMO

From November 2021 to September 2022, we conducted four field surveys on macroinvertebrates and water environmental factors in Xinyang section of the Huaihe River main stream. We analyzed the structure and spatiotemporal distribution characteristics of the functional feeding groups of macroinvertebrates, and evaluated river water quality. A total of 73 macroinvertebrate species were collected in the basin, belonging to 42 families, 7 classes, and 3 phyla. The dominant species of macroinvertebrates changed significantly in different months, with Exopalaemon modestus being the absolute advantage species in the basin in July and September 2022. In different sampling months, the functional feeding group of macroinvertebrates was mainly dominated by shredders, accounting for 35.9%. The results of redundancy analysis showed that the main environmental factors affecting the distribution of functional feeding groups of macroinvertebrates varied across different months, with conductivity in February, temperature in July, and oxidation-reduction potential in September and November. The evaluation based on the biolo-gical index and Shannon index of macroinvertebrates indicated that water quality in the investigated section was at a light pollution level.


Assuntos
Invertebrados , Qualidade da Água , Humanos , Animais , Ecossistema , Rios/química , Monitoramento Ambiental/métodos
7.
BMC Infect Dis ; 12: 29, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22292815

RESUMO

BACKGROUND: 2009 pandemic H1N1 (pH1N1) influenza posed an increased risk of severe illness among pregnant women. Data on risk factors associated with death of pregnant women and neonates with pH1N1 infections are limited outside of developed countries. METHODS: Retrospective observational study in 394 severe or critical pregnant women admitted to a hospital with pH1N1 influenza from Sep. 1, 2009 to Dec. 31, 2009. rRT-PCR testing was used to confirm infection. In-hospital mortality was the primary endpoint of this study. Univariable logistic analysis and multivariate logistic regression analysis were used to investigate the potential factors on admission that might be associated with the maternal and neonatal mortality. RESULTS: 394 pregnant women were included, 286 were infected with pH1N1 in the third trimester. 351 had pneumonia, and 77 died. A PaO(2)/FiO(2) ≤ 200 (odds ratio (OR), 27.16; 95% confidence interval (CI), 2.64-279.70) and higher BMI (i.e. ≥ 30) on admission (OR, 1.26; 95% CI, 1.09 to 1.47) were independent risk factors for maternal death. Of 211 deliveries, 146 neonates survived. Premature delivery (OR, 4.17; 95% CI, 1.19-14.56) was associated neonatal mortality. Among 186 patients who received mechanical ventilation, 83 patients were treated with non-invasive ventilation (NIV) and 38 were successful with NIV. The death rate was lower among patients who initially received NIV than those who were initially intubated (24/83, 28.9% vs 43/87, 49.4%; p = 0.006). Septic shock was an independent risk factor for failure of NIV. CONCLUSIONS: Severe hypoxemia and higher BMI on admission were associated with adverse outcomes for pregnant women. Preterm delivery was a risk factor for neonatal death among pregnant women with pH1N1 influenza infection. NIV may be useful in selected pregnant women without septic shock.


Assuntos
Estado Terminal , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/mortalidade , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/mortalidade , Adolescente , Adulto , China/epidemiologia , Feminino , Morte Fetal/epidemiologia , Humanos , Hipóxia/epidemiologia , Hipóxia/mortalidade , Influenza Humana/patologia , Influenza Humana/virologia , Gravidez , Complicações Infecciosas na Gravidez/patologia , Complicações Infecciosas na Gravidez/virologia , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Adulto Jovem
8.
Front Public Health ; 10: 974488, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276366

RESUMO

Online food delivery (OFD) is one of the top industries in the Online-to-offline (O2O) commerce sector. Deliverymen need to complete a large number of delivery orders in limited default time every day, which cause high working stress to them. Therefore, a high level of traffic violations and crashes by deliverymen and corresponding negative impact on public safety are observed. To reduce traffic violations by deliverymen and resulting crashes, a hierarchical online food delivery framework is proposed, which is based on data from questionnaire surveys conducted in Xi'an City, China. The study includes the analysis of the root cause correlated with traffic violations during online food delivery as part of an empirical study on the priority delivery fee by applying a conditional price sensitivity measurement (PSM) model. The feasibility and rationality of the framework are further investigated by using cross analysis of urban dwellers' occupation, income, and commuting cost. The results identify that, through rationally shunting the demand of online food delivery, prolonging the default delivery duration, and providing diversified delivery services, the proposed hierarchical online food delivery mechanism is able to relieve the stress of deliverymen during peak hours of food requests. This reduces the willingness of deliverymen to engage in traffic violations, and other risky behaviors during food delivery trips. All of which facilitate high-quality and timely online food delivery service while enabling improved safety of deliverymen and others as part of enhanced public safety and health.


Assuntos
Comércio , Renda , China , Cidades , Inquéritos e Questionários
9.
Front Neurosci ; 16: 891772, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720704

RESUMO

To increase the speed and efficiency of expressways construction, information management is being gradually introduced into the construction process. However, progress is limited due to the complexity of expressway engineering and application limitations of information technology. Design and delivery are still dominated by paper files, and the management of test and inspection data is still relatively extensive. Research to date into digital expressway construction has been piecemeal and fragmented with a lack of research related to the whole construction process and a data-centric information management system yet to be realized. In response, through literature research and semi-structured interviews, the framework of a data-driven digital whole-process highway construction management platform was determined. A whole process management platform was established according to the framework, and the functional application of the proposed platform was explained through a case. The framework is proposed from the perspective of the whole process of collaborative sharing., which provides a new way of thinking to solve the problems existing in the current field of expressway construction whole-process management. It also provides data-centric management, electronic design and delivery, a refined workflow, and an efficient management process.

10.
Water Res ; 170: 115300, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756614

RESUMO

Autotrophic iron-dependent denitrification (AIDD) is arising as a promising process for nitrogen removal from wastewater with a low carbon to nitrogen ratio. However, there is still a debate about the existence of such a process in activated sludge systems. This work provides evidence and elucidated the feasibility of autotrophic Fe(II)-oxidizing nitrate-reducing culture for nitrogen removal by long-term reactor operation, batch experimental verification, unstructured kinetic modeling and microbial community analyses. A relatively stable nitrate removal rate was achieved coupled with the oxidation of ferrous ions in 3-month operation of reactor. The kinetic modeling suggests that the iron oxidation was a growth-associated process in AIDD. Utilization of extracellular polymeric substances (and/or soluble microbial products) as electron donor for denitrification by heterotrophic denitrifiers was not mainly responsible for nitrogen removal in the reactor. After long-term operation of the reactor with activated sludge as inoculum, the enrichment culture KS-like consortium, dominated by Fe(II) oxidizer, Gallionellaceae, was successfully acclimated for autotrophic Fe(II)-oxidizing nitrate reduction. This work extents our understanding about the existence of such an autotrophic Fe(II)-oxidizing nitrate-reducing culture in both natural and engineered systems, and opens a door for its potential application in wastewater treatment.


Assuntos
Desnitrificação , Esgotos , Processos Autotróficos , Reatores Biológicos , Ferro , Nitratos , Nitrogênio
11.
Dev Comp Immunol ; 84: 1-13, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29409789

RESUMO

Type II crustins are the most abundant type of crustins in shrimps that exhibit remarkable sequence diversities and broad antibacterial activities. This study characterized a novel type II crustin, SpCrus2, in the mud crab Scylla paramamosain. The SpCrus2 cDNA sequence is 620-bp long with a 495-bp open reading frame encoding a 164-amino acid protein. In the deduced protein, a 17-amino acid signal peptide, a glycine-rich hydrophobic region (GRR), and a cysteine-rich region (CRR) containing a whey acidic protein domain were predicted. SpCrus2 shares high similarity with most type II crustins (types IIa and IIb crustins) in shrimps but has a novel distribution pattern of cysteine residues that is distinct from most crustins. SpCrus2 and PlCrus3 from Pacifastacus leniusculus share high similarity and the same distribution pattern of cysteine residues. Thus, we proposed them as type IIc crustins. SpCrus2 is mainly distributed in the gills and can be up-regulated through Vibrio parahemolyticus or Staphylococcus aureus challenge. To investigate the biological functions of SpCrus2 and the underlying mechanisms, SpCrus2, GRR, CRR, and the mutant of CRR (CRR-M, the cysteine distribution pattern is mutated into that in most conventional crustins) were all overexpressed and purified. SpCrus2 GRR itself, as a glycine-rich amphiphilic peptide, exhibited evident antibacterial ability against Gram-negative bacteria, whereas CRR possessed potent antibacterial activity against Gram-positive bacteria. Either GRR or CRR exhibited weaker antibacterial activity than the whole protein of SpCrus2, indicating that GRR and CRR synergized to exert their potential antibacterial functions. In addition, CRR exhibited slightly stronger antimicrobial activity than CRR-M, suggesting that SpCrus2 containing this novel cysteine distribution pattern may exhibit stronger antimicrobial activity than most type II crustins with the conventional distribution pattern of cysteine residues. The likely antimicrobial ability of SpCrus2 may result from its microbial polysaccharide-binding and agglutination activities. Overall, this study characterized the first type II crustin in crabs and provided new insights into understanding the sequence and functional diversity of crustins and their immune functions in crustaceans.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Proteínas de Artrópodes/genética , Braquiúros/fisiologia , Brânquias/fisiologia , Vibrioses/imunologia , Vibrio parahaemolyticus/fisiologia , Aglutinação , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas de Artrópodes/metabolismo , Evolução Biológica , Clonagem Molecular , Cisteína/genética , Regulação da Expressão Gênica , Imunidade Inata , Penaeidae , Filogenia , Polissacarídeos/imunologia , Domínios Proteicos/genética , Frutos do Mar
12.
Artigo em Chinês | MEDLINE | ID: mdl-18038811

RESUMO

Parasitological and dissection methods were used to confirm Echinococcus infection and echinococcosis in animals, and to understand the epidemiological situation in final and intermediate animal hosts in Qinghai Province. Three Echinococcus species were found in the Province including E. granulosus, E. multilocularis and E. shiquicus. The prevalence of hydatid disease showed a tendency of increase with an average rate of over 50% in yaks and sheep. Higher prevalence in wild animals as intermediate host was found in the southern plateau, while that in final hosts such as dogs and wolves, the prevalence was higher in the area of Qilian mountain. There is a complex chain of life cycle of the parasites among animals, which poses a threat to the health of human population. Effective measures to control the disease in animals are urgently needed.


Assuntos
Equinococose/epidemiologia , Echinococcus/isolamento & purificação , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , China/epidemiologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Equinococose/parasitologia , Equinococose/veterinária , Raposas , Camundongos , Coelhos , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Suínos , Lobos
13.
Artigo em Chinês | MEDLINE | ID: mdl-18038785

RESUMO

The survey was carried out in July, 2006 in Zhiduo County. The IHA and ELISA positive rate in human population was 4.5% (42/933) and 8.2% (76/931) respectively. Ultrasonography revealed a morbidity of 3.4% (33/979) with 3.2% Echinococcus granulosus and 0.2% of E. multilocularis respectively. Animal dissection showed an infection rate of 15.1% (14/93) in pikas with one infected by E. shiquicus proved by molecular biology. Coproantigen rate by ELISA was 62% (12/193) in dogs and 35.7% (5/14) in wolves. The results indicated that Zhiduo County is a mixed endemic area for echinococcosis.


Assuntos
Equinococose/epidemiologia , Echinococcus granulosus/isolamento & purificação , Fezes/parasitologia , Adulto , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Pré-Escolar , China/epidemiologia , Cães , Equinococose/sangue , Equinococose/parasitologia , Echinococcus granulosus/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Lactente , Contagem de Ovos de Parasitas , Prevalência , Lobos
14.
Dev Comp Immunol ; 72: 44-56, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28232132

RESUMO

In crustaceans, anti-lipopolysaccharide factors (ALFs) are important immune effectors that have sequence diversity and exhibit broad antimicrobial activities. In this study, we characterized a novel ALF homolog SpALF6 from mud crab Scylla paramamosain and its variant SpALF6-V, which was generated by mutations of two amino acids (H46 to R and A110 to P) due to the presence of two single nucleotide polymorphisms (SNPs). SpALF6 was an anionic peptide with isoelectric point (pI) 6.79, whereas SpALF6-V was a cationic protein with pI 7.98. These two proteins shared a common lipopolysaccharide (LPS)-binding domain (LBD) with pI 6.05. SpALF6 was expressed mainly in hemocytes and up-regulated by Vibrio parahaemolyticus or Staphylococcus aureus challenge, indicating that SpALF6 may participate in the antibacterial immune responses. To investigate the likely functional differences between SpALF6 and SpALF6-V and elucidate the underlying mechanisms, a single amino acid mutant SpALF6-M (from H46 to R, outside but very close to LBD), which had the same pI as SpALF6-V, was harvested by a fusion PCR. Then, both SpALF6 and SpALF6-M were overexpressed and purified to test antimicrobial activity and binding activity to microbial cells or polysaccharides. SpALF6-M exhibited more potent antimicrobial and cell-binding activity on Gram-positive bacteria and fungi than SpALF6. Furthermore, SpALF6-M possessed stronger lipoteichoic acid (LTA)-binding activity than SpALF6, demonstrating that this particular positively charged amino acid outside but close to LBD contributed to the increase in SpALF6-M antibacterial activity. In addition, SpALF6 LBD peptide and its biotin-labeled form were synthesized in this study. Results showed that this anionic LBD peptide itself did not exhibit any significant antimicrobial activity against 10 kinds of microorganisms but it possessed strong binding activity to LPS, LTA, and peptidoglycan. These findings suggested that this anionic LBD was still an important active center and required collaboration with some particular positively charged amino acids outside LBD to exhibit antibacterial activity. Thus, SpALF6-M antimicrobial activity was increased by the mutation of H46 to R instead of A110 to P, which did not change the protein charge, suggesting that SpALF6-V may have more potent antimicrobial activity than SpALF6 and play more important roles in antibacterial immunity. This study provided a new insight into the mechanisms of how ALF amino acid sequence diversity resulted in their functional divergence.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas de Artrópodes/metabolismo , Infecções Bacterianas/imunologia , Braquiúros/imunologia , Hemócitos/imunologia , Staphylococcus aureus/imunologia , Vibrio parahaemolyticus/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Proteínas de Artrópodes/genética , Evolução Biológica , Clonagem Molecular , Imunidade Inata , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/metabolismo , Mutação/genética , Ligação Proteica
15.
Dev Comp Immunol ; 74: 154-166, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28438599

RESUMO

Lysozymes are widely distributed immune effectors exerting muramidase activity against the peptidoglycan of the bacterial cell wall to trigger cell lysis. However, some invertebrate-type (i-type) lysozymes deficient of muramidase activity still exhibit antimicrobial activity. To date, the mechanism underlying the antimicrobial effect of muramidase-deficient i-type lysozymes remains unclear. Accordingly, this study characterized a novel i-type lysozyme, Splys-i, in the mud crab Scylla paramamosain. Splys-i shared the highest identity with the Litopenaeus vannamei i-type lysozyme (Lvlys-i2, 54% identity) at the amino acid level. Alignment analysis and 3D structure comparison show that Splys-i may be a muramidase-deficient i-type lysozyme because it lacks the two conserved catalytic residues (Glu and Asp) that are necessary for muramidase activity. Splys-i is mainly distributed in the intestine, stomach, gills, hepatopancreas, and hemocytes, and it is upregulated by Vibrio harveyi or Staphylococcus aureus challenge. Recombinant Splys-i protein (rSplys-i) can inhibit the growth of Gram-negative bacteria (V. harveyi, Vibrio alginolyticus, Vibrio parahemolyticus, and Escherichia coli), Gram-positive bacteria (S. aureus, Bacillus subtilis, and Bacillus megaterium), and the fungus Candida albicans to varying degrees. In this study, two binding assays and a bacterial agglutination assay were conducted to elucidate the potential antimicrobial mechanisms of Splys-i. Results demonstrated that rSplys-i could bind to all nine aforementioned microorganisms. It also exhibited a strong binding activity to lipopolysaccharide from E. coli and lipoteichoic acid and peptidoglycan (PGN) from S. aureus but a weak binding activity to PGN from B. subtilis and ß-glucan from fungi. Moreover, rSplys-i could agglutinate these nine types of microorganisms in the presence of Ca2+ at different protein concentrations. These results suggest that the binding activity and its triggered agglutinating activity might be two major mechanisms of action to realize the muramidase-deficient antibacterial activity. In addition, rSplys-i can hydrolyze the peptidoglycan of some Gram-positive bacteria because it exhibits weak isopeptidase activities in salt and protein concentration-dependent manner. This result indicates that such an isopeptidase activity may contribute to the muramidase-deficient antimicrobial activity to a certain degree. In conclusion, Splys-i is upregulated by pathogenic bacteria, and it inhibits bacterial growth by binding and agglutination activities as well as isopeptidase activity, suggesting that Splys-i is involved in immune defense against bacteria through several different mechanisms of action.


Assuntos
Anti-Infecciosos/metabolismo , Proteínas de Artrópodes/genética , Braquiúros/imunologia , Candidíase/imunologia , Mucosa Intestinal/metabolismo , Muramidase/genética , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Vibrioses/imunologia , Vibrio/imunologia , Aglutinação , Animais , Proteínas de Artrópodes/metabolismo , Carbono-Nitrogênio Liases/metabolismo , Processos de Crescimento Celular , Clonagem Molecular , Imunidade Inata , Lipopolissacarídeos/metabolismo , Muramidase/metabolismo , Ligação Proteica , Proteoglicanas/metabolismo , Alinhamento de Sequência
16.
Huan Jing Ke Xue ; 38(3): 918-923, 2017 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965561

RESUMO

The biodegradation of gas-phase mixtrue of dimethyl sulfide (DMS) and 1-propanethiol (PT) was examined in a biotrickling filter (BTF), inoculated with a microbial consortium composed of activated sewage sludge, and pure strains of Alcaligenes sp. SY1 and Pseudomonas putida. S-1. BTF could be successfully started up within only 11 days when the inlet concentrations of DMS and PT were both 50 mg·m-3 and EBRT was 30 s, with 90% removal efficiency (RE) of DMS and 100% RE of PT. In the steady state, the maximum elimination capacities of DMS and PT were 8.7 g·(m3·h)-1 and 12.4 g·(m3·h)-1, respectively. The presence of PT with a concentration up to 51 mg·m-3 showed an antagonistic removal pattern for DMS, but the opposite did not occur. Meanwhile, the BTF showed high efficiency in the biodegradation of H2S. When the concentration of H2S was as high as 230 mg·m-3, the RE of H2S could reach 98%. However, H2S showed a declining effect on the removal of DMS when the concentration exceeded 115 mg·m-3.


Assuntos
Reatores Biológicos/microbiologia , Filtração , Odorantes , Esgotos/microbiologia , Enxofre/isolamento & purificação , Alcaligenes , Sulfeto de Hidrogênio/isolamento & purificação , Pseudomonas putida
17.
Chin Med J (Engl) ; 126(12): 2222-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23786929

RESUMO

BACKGROUND: The 2009 pandemic H1N1 (pH1N1) influenza showed that relatively young adults accounted for the highest rates of hospital admission and death. In preparation for pH1N1, the aim of the study is to identify factors associated with the mortality of patients with 2009 pH1N1 infection, especially for young patients without chronic medical conditions. METHODS: Retrospective observational study of 2151 severe or critical adult cases (≥ 14 years old) admitted to a hospital with pH1N1 influenza from September 1, 2009 to December 31, 2009 from 426 hospitals of 27 Chinese provinces. A confirmed case was a person whose pH1N1 virus infection was verified by real-time reverse-transcriptase polymerase chain reaction (rRT-PCR). Severe and critical cases were defined according to the H1N1 2009 Clinical guidelines (Third Edition, 2009) released by the Ministry of Health of China. RESULTS: Among the 2151 patients, the mean age was 34.0 years. Two hundred and ninty-three (13.6%) died during hospital stay. One thousand four hundred and forty-two patients (67.0%) had no comorbidities and 189 (13.1%) of them died. Pregnancy (OR 8.03), pneumonia (OR 8.91), dyspnea (OR 3.95), central nervous system (CNS) symptom (OR 1.55), higher APACHE (Acute Physiology and Chronic Health Evaluation) II score (OR 1.06), Alanine aminotransferase (ALT) (OR 1.002), and the lactate dehydrogenase (LDH) level (OR 1.001) were independent risk factors for death among adults without chronic medical conditions. Higher APACHE II score (OR 1.08) and age (OR 1.06) were independent risk factors for death among adults with respiratory diseases. A multivariate analysis showed an association between mortality and CNS symptoms (OR 2.66), higher APACHE II score (OR 1.03), ALT (OR 1.006), and LDH level (OR 1.002) in patients with cardiovascular diseases. Dyspnea (OR 11.32) was an independent risk factor for patient death in patients with diabetes mellitus. CONCLUSION: Clinical knowledge of identified prognostic factors for mortality may aid in the management of adult influenza infection.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/mortalidade , Pandemias , APACHE , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
18.
World J Emerg Med ; 3(1): 40-3, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-25215037

RESUMO

BACKGROUND: The complications of systemic inflammatory response syndrome (SIRS) include acute lung injury, acute kidney injury, shock, and multiple organ dysfunction syndrome (MODS). In recent years, how to clear inflammatory mediators has become a hot topic in critical care medicine. Researchers hypothesize that continuous blood purification (CBP) can effectively eliminate a variety of inflammatory mediators which participate in the occurrence of MODS and adjust the immune imbalance. This study aimed to observe the effects of CBP in MODS patients. METHODS: In this retrospective clinical study, a total of 38 MODS patients, 18 males and 20 females, were enrolled. After conventional therapy, all the patients received CBP. Biochemistry, blood gas analysis, oxygenation index, mean arterial blood pressure (MAP), acute physiology and chronic health evaluation (APACHE) II scores were monitored. RESULTS: After CBP, the vital signs of patients were rapidly stable, and electrolyte disorders and acid-base imbalance were corrected. Renal function, blood gas, oxygenation index were all improved. MAP was increased, and APACHE II score was significantly decreased. All patients had good tolerance, stable hemodynamics, and no obvious adverse reaction on CBP compared with pre-CBP. CONCLUSION: CBP can effectively clean toxins, correct electrolyte acid-base balance, and improve systemic inflammatory response syndrome and the organ function of MODS patients.

19.
World J Emerg Med ; 2(2): 88-92, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-25214990

RESUMO

BACKGROUND: Sepsis and secondary multiple organ failure in critically ill patients are the major cause of death, but the pathogenesis of sepsis is not clear, especially the dysfunction of the immune system. In this paper, we review the response and regulation of the immune system and the functions of a variety of inflammatory mediators in sepsis. DATA SOURCES: Studies were identified by searching MEDLINE and PubMed for articles using the keywords "sepsis", "immune response", and "inflammatory mediator" up to October 2010. Additional papers were identified by a manual search of the references from the key articles. RESULTS: THIS SYSTEMATIC REVIEW WAS CONDUCTED OF: 1) the immune response; 2) immune regulation; 3) inflammatory mediators; 4) high-mobility group box 1 protein; 5) the complement system; and 6) the autonomic nervous system. There are no therapeutic approaches available for sepsis that target inflammatory response; the mortality of sepsis has not been significantly reduced. CONCLUSIONS: Sepsis is complex and dynamic, and it has a group of heterogeneous syndromes. Since different patients with sepsis have different etiology, susceptibility, and responses, treatment should be prescribed individually.

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