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1.
Growth Factors ; 38(3-4): 167-176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33719806

RESUMO

Cell entry of influenza A virus (IAV) was reported to be promoted by epidermal growth factor receptor (EGFR). On the other hand, binding of heparin-binding EGF-like growth factor (HB-EGF) to EGFR leads to internalisation and degradation of the receptors. This study aimed to testify whether or not HB-EGF-induced downregulation of EGFR could attenuate IAV cell entry and subsequently diminish the infection. Immunoblotting and plaque assay revealed that HB-EGF-induced degradation of EGFR led to reduction of viral matrix 1 protein level and suppressed virion production. In addition, immunoblotting and imaging flow cytometric analysis demonstrated that IAV-induced phosphorylation of STAT1 and its localisation to nucleus in the early stage of infection were inhibited by HB-EGF treatment. This suggested the potential of HB-EGF in modulating uncontrolled and exaggerated inflammatory response caused by IAV infection. Together these findings attest the potential of HB-EGF mediated endocytosis and degradation of EGFR as a novel anti-IAV strategy.


Assuntos
Fator de Crescimento Epidérmico , Vírus da Influenza A , Heparina , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Vírus da Influenza A/metabolismo , Fosforilação
2.
Indoor Air ; 28(2): 258-265, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29130534

RESUMO

One of the most notable Indoor Air Quality problems is odor emission. This study investigated the potential contribution of skin squames to the production of ammonia (NH3 ) and volatile organic acids (VFAs) by 7 bacteria isolated from air-cooling (AC) units with complaints of urine and body odors. Our previous study showed that keratinolytic activity is higher in AC units with odor complaints than those without. In the offices where these units are located, the most likely source of keratins is from human skin squames. Most bacteria can produce NH3 and VFAs in the skin squame culture. Some correlations between the levels of NH3 , NH4+, VFAs, and keratinolytic activity were found. The odor production pathway with skin squames was proposed. Staphylococcus haemolyticus was abundant in the AC units with odor problems and had a high level of keratinolytic activity in addition to odor production. For long-term odor control, it is important to reduce the level of skin squames entering the AC units.


Assuntos
Ar Condicionado , Poluentes Atmosféricos/análise , Amônia/análise , Ácidos Graxos Voláteis/análise , Odorantes/análise , Pele/química , Contagem de Colônia Microbiana , Monitoramento Ambiental , Humanos , Pele/microbiologia , Staphylococcus haemolyticus/crescimento & desenvolvimento
3.
Asian J Anesthesiol ; 55(4): 87-88, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29122588

RESUMO

Tracheal bronchus is a congenital anatomical variant of patients with accessory bronchus in the right upper lobe deriving directly from the supracarinal trachea. Pre-operative consultation with the anesthesiologist is important for patient safety and can avoid adverse effects induced by endotracheal intubation. In this report, we described a case of tracheal bronchus in which general anesthesia was performed for video-assisted thoracoscopic surgery. We discussed some of the issues surrounding to complications in tracheal bronchus.


Assuntos
Anestesia Geral/métodos , Brônquios/anormalidades , Traqueia/anormalidades , Humanos , Masculino , Pessoa de Meia-Idade , Cirurgia Torácica Vídeoassistida
4.
J Hosp Infect ; 91(3): 278-81, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26412395

RESUMO

Using a Collison nebulizer, aerosols of influenza (A/Udorn/307/72 H3N2) were generated within a controlled experimental chamber, from known starting virus concentrations. Air samples collected after variable suspension times were tested quantitatively using both plaque and polymerase chain reaction assays, to compare the proportion of viable virus against the amount of detectable viral RNA. These experiments showed that whereas influenza RNA copies were well preserved, the number of viable viruses decreased by a factor of 10(4)-10(5). This suggests that air-sampling studies for assessing infection control risks that detect only influenza RNA may greatly overestimate the amount of viable virus available to cause infection.


Assuntos
Aerossóis , Microbiologia do Ar , Vírus da Influenza A Subtipo H3N2/fisiologia , Viabilidade Microbiana , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Viral , Ensaio de Placa Viral
5.
Int J Tuberc Lung Dis ; 16(8): 1023-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22691609

RESUMO

SETTING: A combination of environmental measurement and mathematical modelling may provide a more quantitative method to inform the tuberculosis (TB) screening process in non-household settings following diagnosis of an infectious case. OBJECTIVE: To explore different methods for environmental assessment and mathematical modelling to predict TB transmission risk and devise a tool for public health practitioners for use in TB investigations. DESIGN: Parameters including air flow, carbon dioxide (CO(2)) and airborne particles were measured over 3 working days in an office with a staff member with infectious TB. The Wells-Riley model was applied to predict transmission rates. RESULTS: The results suggested that poor ventilation and well-mixed air led to equal exposure of staff members to airborne TB bacilli. The model's prediction of attack rate (42%) supported the actual number of infections that occurred (50%). CONCLUSION: This study supports the use of environmental assessment and modelling as a tool for public health practitioners to determine the extent of TB exposure and to inform TB screening strategies. CO(2) and airborne particle profiles, both measured via a handheld device, provide the greatest practicality and amount of information that public health practitioners can use. Further studies will validate the level of screening required related to these measurements.


Assuntos
Busca de Comunicante , Técnicas de Apoio para a Decisão , Meio Ambiente , Monitoramento Ambiental , Programas de Rastreamento , Exposição Ocupacional , Tuberculose/diagnóstico , Local de Trabalho , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Dióxido de Carbono/análise , Monitoramento Ambiental/métodos , Monitoramento Epidemiológico , Humanos , Londres , Modelos Teóricos , Saúde Ocupacional , Material Particulado/análise , Seleção de Pacientes , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Tuberculose/epidemiologia , Tuberculose/transmissão , Ventilação
6.
Poult Sci ; 89(4): 729-37, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20308405

RESUMO

The shell of the duck egg did not crack after pressure treatments (300 to 500 MPa; 25 degrees C; 10 min) in this study; therefore, the changes of physicochemical properties of egg white and yolk proteins from the intact shell egg by pressure treatment were first investigated and compared with those of pressurized hen liquid eggs. Although the proximate compositions of duck eggs and hen eggs were similar, the moisture and protein contents of hen whole eggs were higher than those of duck whole eggs. The protein contents of duck egg white and yolk were slightly lower than those of hen eggs, and the moisture content of duck egg white was equal to that of hen egg white, whereas that of duck egg yolk was lower than that of hen egg yolk. After pressure treatment at 500 MPa, the results of solubility, sulfhydryl content, surface hydrophobicity, and residual denaturation enthalpy showed that egg white proteins underwent slight but significant unfolding and aggregation, whereas pressure treatments below 500 MPa induced insignificant changes in the physicochemical properties. On the other hand, pressure treatments at 400 and 500 MPa significantly reduced the solubility and residual denaturation enthalpy of egg yolk proteins. However, the native PAGE result showed that pressure treatment up to 500 MPa did not affect the protein components of egg white and yolk. The results showed that the application of pressure treatment on duck shell egg may induce reversible denaturation of both egg white and yolk proteins. The egg white and yolk proteins may be prevented from denaturation after pressure treatment in the presence of the eggshell compared with the absence of the eggshell. As reported in the literature, pressure treatments at 300 to 500 MPa and 25 degrees C would be efficient for decontamination of duck shell eggs. Therefore, based on the consideration for food safety and functional properties, pressure processing can be a good preservation technique for duck shell eggs.


Assuntos
Proteínas do Ovo/análise , Casca de Ovo/química , Animais , Patos , Feminino , Concentração de Íons de Hidrogênio , Pressão Hidrostática , Pressão , Desnaturação Proteica , Solubilidade , Compostos de Sulfidrila/análise
7.
Poult Sci ; 89(4): 738-44, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20308406

RESUMO

Changes in oil exudation and histological structures of salted duck egg yolks during brining up to 5 wk were investigated. During brining, the salt contents of albumen, exterior yolk (hardened portion), and interior yolk (soft or liquid portion) gradually increased accompanied by slight decreases in moisture content. The hardening ratio of salted egg yolks increased rapidly to about 60% during the first week of brining and then reached 100% at the end of brining. After brining, part of the lipids in salted egg yolk became free due to the structural changes of low-density lipoprotein induced by dehydration and increase of salt content, and more free lipids in salted egg yolk were released after the cooking process. With the brining time increased up to 5 wk, the outer region of the cooked salted yolk gradually changed into dark brown, brown, orange, and then dark brown, whereas the center region changed into light yellow, yellow, dark yellow, and then yellow again. The microstructures of cooked salted egg yolks showed that the yolk spheres in the outer and middle regions retained their original shape, with some shrinking and being packed more loosely when brining time increased, and the exuded oil filled the space between the spheres. Furthermore, the yolk spheres in the center region transformed to a round shape but still showed granulation after 4 wk of brining, whereas they were mostly disrupted after 2 to 5 wk of brining. One of the most important characteristics of cooked salted egg yolks, gritty texture, contributed to oil exudation and granulated yolk spheres were observed at the brining time of 4 wk.


Assuntos
Gema de Ovo/química , Animais , Patos , Gema de Ovo/efeitos dos fármacos , Gema de Ovo/ultraestrutura , Feminino , Lipídeos/análise , Microscopia Eletrônica de Varredura , Óleos/análise , Oviposição , Cloreto de Sódio/farmacologia
8.
Chemosphere ; 73(5): 791-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18672265

RESUMO

This paper evaluates the effects of pig manure compost (PMC) and Tween 80 on the removal of phenanthrene (PHE) and pyrene (PYR) from soil cultivated with Agropyron elongatum. Soils spiked with about 300 mg kg(-1) of PHE and PYR were individually amended with 0%, 2.5%, 5% and 7.5% (dry wt) of PMC or 0, 20 and 100 mg kg(-1) of Tween 80. Unplanted and sterile microcosms were prepared as the controls. PAH concentration, total organic matter (TOM), dissolved organic carbon (DOC), total heterotrophic and PAH degrading microbial populations in soil were quantified before and after 60d period. The results indicated that A. elongatum could significantly enhance PYR removal (from 46% to 61%) but had less impact on PHE removal (from 96% to 97%). Plant uptake of the PAHs was insignificant. Biodegradation was the key mechanism of PAH removals (<3% losses in the sterile control). Increase in PMC or Tween 80 levels increased the removal of PYR but not of PHE. Maximal PYR removal of 79% and 92% were observed in vegetated soil receiving 100 mg kg(-1) Tween 80 and 7.5% PMC, respectively. Enhanced PYR removal in soil receiving PMC could be explained by the elevated levels of DOC, TOM and microbial populations as suggested by Pearson correlation test. While the positive effect of Tween 80 on PYR removal could probably due to its capacities to enhance PYR bioavailability in soil. This paper suggests that the addition of either PMC or nonionic-surfactant Tween 80 could facilitate phytoremediation of PAH contaminated soil.


Assuntos
Esterco , Fenantrenos/isolamento & purificação , Polissorbatos/química , Pirenos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Agropyron/metabolismo , Animais , Biodegradação Ambiental , Esterco/microbiologia , Fenantrenos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pirenos/química , Solo , Suínos
9.
Environ Technol ; 27(3): 329-35, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16548213

RESUMO

An extensive growth of Stachybotrys in water-damaged buildings is of great public health concern. It is inconclusive whether Stachybotrys is responsible for the reported health effects on the occupants in these contaminated environments. However, based on the veterinary, occupational and laboratory toxicity studies, it is reasonable to project that Stachybotrys can cause adverse health responses once the toxic level of the corresponding agents reached the target systems. In order to assess the risk to occupants in contaminated buildings, it is essential to outline and collect information for risk assessment. This review paper presents the current information in the format of hazard identification, dose-response and environmental characteristics and aims to discuss existing information with researchers and risk assessors and help to conduct risk characterization under different indoor conditions.


Assuntos
Micotoxinas/efeitos adversos , Stachybotrys/química , Materiais de Construção , Ecologia , Humanos , Dinâmica Populacional , Saúde Pública , Medição de Risco , Stachybotrys/crescimento & desenvolvimento , Água
10.
J Cardiovasc Surg (Torino) ; 46(2): 163-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15793496

RESUMO

AIM: Multiple-trauma patients often have injuries that prevent the use of anticoagulant or sequential compression device prophylaxis. Temporary inferior vena cava filters (IVCFs) offer protection against pulmonary embolism (PE) during the early, highest-risk perioperative and immediate injury period, while avoiding potential long-term sequelae of a permanent IVCF. The objective of this study was to evaluate the efficacy of prophylactic, temporary IVCF placement at the intensive care unit (ICU) bedside under real-time intravascular ultrasound (IVUS) guidance in multiple-trauma patients. METHODS: One hundred and three multiple-trauma patients between July 1, 2002, and July 1, 2004, under-went placement of Günther-Tulip (n=38), Recovery (n=30) or OptEase (n=35) retrievable IVCFs under real-time IVUS guidance. The mean+/-SD injury severity score of the patients was 27.7 (+/-2.2). All patients had abdominal X-rays to verify filter location. Before IVCF retrieval, all patients underwent femoral vein color-flow ultrasonography to rule out deep vein thrombosis (DVT) and pre and postprocedure vena-cavography for possible IVCF thrombus entrapment and postretrieval IVC injury. RESULTS: Twenty-four patients died of their injuries; no deaths were related to IVCF placement. One PE occurred during follow-up after filter retrieval, and 2 insertion site femoral vein DVT occurred. As verified by abdominal X-rays, 97.1% (100/103) of IVCFs were placed without complications at the L2-3 level. Filter-related complications included 3 groin hematomas (2.9%) and 3 IVCFs misplaced in the right iliac vein early in our experience; these filters were uneventfully retrieved and replaced in the IVC within 24 h. Forty-four patients underwent uneventful retrieval of IVCFs after DVT or PE anticoagulation prophylaxis was initiated. Thirty-five filters were not removed, including 32 because severity of injury prevented DVT or PE prophylaxis and 3 because of thrombus trapped with the filter. CONCLUSIONS: Prophylactic, temporary IVCFs placed at the ICU bedside under IVUS guidance in multiple-trauma patients serves as an effective bridge to anticoagulation until venous thromboembolism prophylaxis can be initiated. Further investigation of this bedside technique and the role of temporary IVCFs in these patients is warranted.


Assuntos
Remoção de Dispositivo , Filtros de Veia Cava , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Feminino , Veia Femoral/diagnóstico por imagem , Veia Femoral/fisiopatologia , Veia Femoral/cirurgia , Seguimentos , Humanos , Veia Ilíaca/diagnóstico por imagem , Veia Ilíaca/fisiopatologia , Veia Ilíaca/cirurgia , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/diagnóstico por imagem , Traumatismo Múltiplo/mortalidade , Traumatismo Múltiplo/cirurgia , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiologia , Embolia Pulmonar/prevenção & controle , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Índices de Gravidade do Trauma , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Ultrassonografia de Intervenção , Grau de Desobstrução Vascular , Filtros de Veia Cava/efeitos adversos , Trombose Venosa/diagnóstico , Trombose Venosa/etiologia , Trombose Venosa/prevenção & controle
11.
Sci Total Environ ; 289(1-3): 159-68, 2002 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-12049392

RESUMO

This study undertakes an initial prediction of the bioaccumulation factors and body burden of the steroid estrogens, estrone, estradiol, estriol and ethinylestradiol in a range of aquatic organisms (plankton, benthic and free-living invertebrates and fish) in river systems using a food-web model. These data are compared to that derived from less complex predictions based on octanol-water partition coefficient and molecular connectivity index. The model predicted that bioaccumulation of steroid estrogens occurred in all organisms, however, the values were small, and the maximum and minimum bioaccumulation factors in this study were found in the fish at the lowest trophic level with ethinylestradiol (332) and the fish at the highest trophic level with estriol (1.8), respectively. Moreover, the bioaccumulation factors were sensitive to the metabolic rates of the estrogens in the free living organisms, while the concentration of estrogens in sediment was a significant factor in determining these values in benthic invertebrates. Biomagnification contributed little to the overall bioaccumulation, but the importance increased in fish exposed to ethinylestradiol. The predicted bioaccumulation factors from the food web model were generally smaller than the calculated bioconcentration factors from the simpler octanol-water partition coefficient/molecular connectivity index based estimates. Compared to literature measured data, the predicted values for fish were approximately 1000 times less than the values observed in laboratory tests, while for invertebrates, the modeled values were less than two orders of magnitude below laboratory results. However, the model predicted a similar bioconcentration factor for plankton in relation to experimental data for Chlorella vulgaris for estrone and estriol.


Assuntos
Congêneres do Estradiol/farmacocinética , Estrogênios/farmacocinética , Peixes , Cadeia Alimentar , Invertebrados , Modelos Teóricos , Plâncton , Poluentes Químicos da Água/farmacocinética , Animais , Carga Corporal (Radioterapia) , Exposição Ambiental , Previsões , Distribuição Tecidual
12.
Crit Rev Toxicol ; 32(2): 113-32, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11951992

RESUMO

Laboratory-based acute toxicity data and physiological studies relating to natural and synthetic steroid estrogens in a range of animals and plants are reviewed. Steroid estrogens may induce adverse effects in animals that do or do not express the estrogen receptor, and in plants, and they may mimic other hormones or induce nonestrogenic effects. Although the findings of such studies should be treated with caution when extrapolated to possible environmental effects, the available data indicate that a wide range of effects may be manifested in a diversity of species. The environmental occurrence of the compounds and possible environmental exposure routes are also reviewed and discussed in relation to the laboratory-based acute toxicity data. While there are likely to be difficulties in relating some of the observed laboratory data to possible environmental effects, studies undertaken on fish are directly relevant because exposure pathways and concentrations were related to those occurring in the environment. Effects that may occur in the environment are discussed in relation to their significance to the individual and at the species level.


Assuntos
Carcinógenos/toxicidade , Estrogênios/toxicidade , Esteroides/toxicidade , Animais , Relação Dose-Resposta a Droga , Ecologia , Estrogênios/isolamento & purificação , Feminino , Humanos , Masculino , Medição de Risco , Esgotos , Esteroides/isolamento & purificação
13.
Appl Environ Microbiol ; 68(2): 859-64, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11823229

RESUMO

The biotransformation and bioconcentration of natural and synthetic steroid estrogens by Chlorella vulgaris were investigated by using batch-shaking experiments with incubation for 48 h in the light or dark. Estradiol and estrone were interconvertible in both light and dark conditions; however, this biotransformation showed a preference for estrone. In the light, 50% estradiol was further metabolized to an unknown product. Apart from biotransformation, estrone, as well as hydroxyestrone, estriol, and ethinylestradiol, was relatively stable in the algal culture, whereas estradiol valerate was hydrolyzed to estradiol and then to estrone within 3 h of incubation. All of the tested estrogens exhibited a degree of partitioning to C. vulgaris; however, the concentrations of estriol, hydroxyestrone, ethinylestradiol, and estradiol valerate were always below the quantification limits. For estradiol and estrone, the partitioning of these estrogens in the algal extracts to the filtrates was <6% of the total amount present. The average concentration factor for estrone was ca. 27; however, the concentration factor for estradiol was not reported since no equilibrium was reached between the aqueous solution and that within the cells due to continuing biotransformation.


Assuntos
Chlorella/metabolismo , Estradiol/análogos & derivados , Estrogênios/metabolismo , Chlorella/crescimento & desenvolvimento , Meios de Cultura , Escuridão , Estradiol/metabolismo , Estrogênios/química , Luz
14.
Int J Legal Med ; 114(4-5): 281-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11355412

RESUMO

The allele distributions at the 12 short tandem repeat (STR) loci D3S1358, HUMvWA, HUMFIBRA/FGA, HUMTHO1, HUMTPOX, HUMCSF1P0, D5S818, D13S317, D7S820, D8S1179, D21S11 and D18S51 have been determined for 284 unrelated Chinese in Hong Kong. The combined probability of identity for the 12 STR loci was about 4.1 x 10(-14) and the overall probability of excluding paternity 0.999978. None of the 12 loci were found to deviate from Hardy-Weinberg expectations according to the results of the exact test. There was also little evidence for association of alleles between loci. The results demonstrate that the loci are useful for forensic human identification and parentage testing for the Chinese population in Hong Kong.


Assuntos
Impressões Digitais de DNA/métodos , Sequências de Repetição em Tandem , China/etnologia , Frequência do Gene , Hong Kong , Humanos , Desequilíbrio de Ligação , Paternidade , Reação em Cadeia da Polimerase
16.
Forensic Sci Int ; 115(1-2): 103-5, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11056276

RESUMO

Allele frequencies for three STR loci, namely, CSF1PO, HUMTHO1 and TPOX, and the AMP-FLP locus D1S80 were obtained from a sample of 351 unrelated Chinese in Hong Kong.


Assuntos
Frequência do Gene/genética , Repetições Minissatélites/genética , Polimorfismo Genético/genética , China/etnologia , Consanguinidade , Hong Kong , Humanos
17.
Environ Technol ; 22(12): 1487-95, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11873884

RESUMO

A greenhouse experiment was conducted to evaluate the growth of Brassica chinensis L. in an acidic loamy soil amended with municipal biosolids with or without lime treatment (750 mg kg(-1)). The soil was amended with one of two municipal biosolids from Tai Po (TP) or Yuen Long (YL) wastewater treatment plants at application rates of 0, 5, 10, 25 and 50% (v/v). Initial NH(+)4-N and PO(3-)4-P concentrations in the amended soil increased with an increase in municipal biosolids loading rates and those with biosolids from TP had a greater increase in nutrients than those from YL. However, initial NO(-)3-N contents in both municipal biosolids amended soils decreased with an increase in biosolids loading rates, particularly for the soil amended with YL. Soluble K, Mg, Na and Ca concentrations in the soil increased with application rates. Municipal biosolids amended soil without lime treatment had higher NH(+)4-N, NO(-)3-N and major cation contents than those with lime. Addition of Tai Po municipal biosolids and lime significantly increased the dry weight yields of B. chinensis L., while YL municipal biosolids increased yields only at the 5% rate with lime amendment. The maximum growth was obtained at municipal biosolids application rates of 5 and 10% for TP and 5% for YL for limed soil. Addition of municipal biosolids increased the total N, P, Zn, Cr and major cation concentrations in the shoot tissue, while lime treatment reduced Zn and Cr contents. The high salt and metal concentrations would likely be factors inhibiting plant growth at high application rates, especially for YL biosolids. Further studies to determine the long-term effects of biosolid application on soil and crop quality are warranted.


Assuntos
Brassica/crescimento & desenvolvimento , Compostos de Cálcio , Óxidos , Esgotos , Solo , Cálcio/análise , Concentração de Íons de Hidrogênio , Magnésio/análise , Potássio/análise , Eliminação de Resíduos/métodos , Sódio/análise
18.
Genes Dev ; 14(9): 1132-45, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10809671

RESUMO

The ShcA gene products have served as a model for the analysis of phosphotyrosine-recognition domains, and for the functions of docking proteins during tyrosine kinase signaling. Here we show that ShcA is primarily expressed in the cardiovascular system during early mouse embryogenesis and regulates both heart development and establishment of mature blood vessels. Targeted mutation suggests that the ShcA adaptor is a pivotal target of tyrosine kinases that selectively potentiates activation of the MAP kinase pathway in the remodeling vasculature. Biochemical analysis of mutant cells shows that ShcA sensitizes cells to growth factor-induced MAP kinase activation, and also organizes cytoskeletal rearrangement in response to the extracellular matrix. ShcA may therefore orchestrate complex interactions within the vascular compartment by rendering cells permissive to respond to soluble and adhesive external cues.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Sistema Cardiovascular/embriologia , Proteínas/genética , Proteínas/metabolismo , Animais , Vasos Sanguíneos/embriologia , Desenvolvimento Embrionário e Fetal , Coração/embriologia , Homozigoto , Camundongos , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neovascularização Fisiológica/genética , Fosfotirosina , Receptores Proteína Tirosina Quinases/metabolismo , Mapeamento por Restrição , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
19.
J Agric Food Chem ; 47(2): 733-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10563961

RESUMO

To elucidate the relationship between shyandan yolk formation and NaCl penetration degree, fresh duck eggs were brined in 26% NaCl and a prolonged brining test was conducted for up to 24 weeks. Shyandan yolk was obtained from brine-cured duck shell eggs in 26% NaCl for 4-6 weeks and subsequently heated at 85 degrees C for 90 min. Though NaCl contents for albumen and yolk increased to 14.8 and 8.9%, respectively, during the prolonged test for up to 24 weeks, the R values (NaCl/water x 100) were similar (increased from 0.6 to 21) throughout the brining process. The oil-off ratio of the yolk increased rapidly from 14 to 50% (0-6 weeks) and gradually decreased during the extended brining. Granulation and gelation of yolk appeared in the different stages of the brining process. This study demonstrates that the formation of shyandan yolk was determined by the degree of NaCl penetration.


Assuntos
Patos , Gema de Ovo/química , Animais , Culinária , Conservação de Alimentos , Cloreto de Sódio , Fatores de Tempo
20.
Biotechnol Prog ; 15(3): 439-45, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10356260

RESUMO

The effect of SecB chaperone on production of periplasmic penicillin acylase (PAC) in Escherichia coli was investigated. It appears that formation of PAC required the function of SecB chaperone and the amount of SecB required was at a basal level. The secB mutant was defective in production of PAC, and the impairment could be complemented by extrachromosomally supplementing SecB in trans. The function of SecB might be primarily stabilizing the cytoplasmic PAC precursors. Overproduction of SecB chaperone usually resulted in an increase in the amount of PAC precursors without enhancing PAC activity. In addition, most of the PAC precursors were located in the periplasm, suggesting that formation of active PAC was likely limited by periplasmic processing steps.


Assuntos
Proteínas de Bactérias/metabolismo , Escherichia coli/enzimologia , Chaperonas Moleculares/metabolismo , Penicilina Amidase/biossíntese , Proteínas de Bactérias/genética , Biotecnologia , Escherichia coli/genética , Expressão Gênica , Genes Bacterianos , Vetores Genéticos , Chaperonas Moleculares/genética , Mutação , Plasmídeos/genética
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