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1.
Zhonghua Yi Xue Za Zhi ; 103(8): 598-601, 2023 Feb 28.
Artículo en Zh | MEDLINE | ID: mdl-36822872

RESUMEN

A total of 36 patients with suspected peritoneal dialysis (PD) catheter dysfunction in the First Hospital of China Medical University from June 2020 to August 2022 were included, and five patients with normal PD catheter were also included as the control group. There were 22 males and 19 females, and aged (45±21) years. The volume of rapid-phase drainage in the control and dysfunction groups was (2 086±65) and (1 181±637) ml, and the total drainage time was (15.2±1.3) and (38.3±14.9) min, respectively. The volume of rapid-phase drainage in the dysfunction group was reduced and the total drainage time was longer than that in the control group (both P<0.05). Compared with group with PD catheter migration, the duration of new bag instillation was prolonged, the drainage volume in the rapid-phase was reduced, the total drainage duration was prolonged, and the ultrafiltration volume was decreased in the group with PD catheter obstruction (all P<0.05). The rapid exchange test can provide an early preliminary diagnosis of PD catheter dysfunction and identify the type of catheter dysfunction.


Asunto(s)
Diálisis Peritoneal , Masculino , Femenino , Humanos , Cateterismo , Catéteres , Drenaje , China , Catéteres de Permanencia
2.
Med J Malaysia ; 73(1): 16-24, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29531198

RESUMEN

BACKGROUND: The Diabetes Mellitus in the Offspring Questionnaire (DMOQ) assesses the perceptions of Type 2 diabetes mellitus (T2DM) patients on the risk of their offspring developing T2DM and the possibility of intervention to reduce this risk. It has 34 items framed within seven domains. This study aimed to adapt, translate and validate the DMOQ from English into the Malay language. METHODS: This was a cross-sectional validation study among 159 T2DM patients attending a public primary care clinic in Selangor. The DMOQ English version underwent adaptation, translation, face validation and field testing to produce the Malay version. Psychometric analysis was performed using Exploratory Factor Analysis, internal consistency and testretest reliability. RESULTS: The DMOQ domains were conceptually equivalent between English and Malay language. A total of 13 items and two domains were removed during the validation process (three items during the content validation, three items due to poor factor loadings, five items as they loaded onto two domains which were not interpretable, one item as it did not fit conceptually into the factor it loaded onto and one openended question as it did not fit into the retained domains). Therefore, the final DMOQ Malay version consisted of 21- items within five domains. The Cronbach alpha was 0.714 and the intraclass-correlation coefficient was 0.868. CONCLUSION: The DMOQ Malay version is a valid and reliable tool which is consistent over time. It can be used to examine the perception of T2DM patients towards the risk of their offspring developing diabetes and possibility of intervention in Malay-speaking patients.


Asunto(s)
Diabetes Mellitus Tipo 2/psicología , Padres/psicología , Hijo de Padres Discapacitados/estadística & datos numéricos , Estudios Transversales , Diabetes Mellitus Tipo 2/epidemiología , Análisis Factorial , Femenino , Humanos , Malasia , Masculino , Persona de Mediana Edad , Psicometría , Reproducibilidad de los Resultados , Factores de Riesgo , Encuestas y Cuestionarios , Traducción
3.
Zhonghua Fu Chan Ke Za Zhi ; 51(4): 270-8, 2016 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-27116985

RESUMEN

OBJECTIVE: By detecting the DNA methylation and gene expression of long-chain 3-hydroxyacyl CoA dehydrogenase(LCHAD)in trophoblast cells, analyze the correlation of DNA methylation and gene expression in early-onset preeclampsia(EPE), hemolysis, elevated liver enzymes, and low platelets(HELLP)syndrome and antiphospholipid syndrome(APS), to investigate the molecular basis of long-chain fatty acid oxidation changes in different preeclampsia and pathological pregnancy. METHODS: Primary human cytotrophoblast cells and HTR8/Svneo cells were treated with serum from patients with EPE(14 cases), HELLP(12 cases), APS(14 cases), and normal pregnant women(NP, 14 cases). The methylation level of LCHAD gene promoter region through the MassARRAY platform and mRNA expression level by real-time fluorescent quantitative PCR technique were conducted. RESULTS: (1)Cytosine-phosphate-guanine(CpG)sites in human LCHAD DNA promoter region: CpG sites were detected in the range of 558 bp before LCHAD gene transcription start site, the detected CpG sites were 11 sites including 8 single sites and 3 complex sites. The position of these sites were at-984,-960,-899,-853,-811,-796,-774,-727,-615,-595,-579 respectively.(2)The sites of-899,-853,-615 and-595 showed increased methylation level in EPE and HELLP groups. The methylation level at-899,-853 and-615 sites in EPE and HELLP groups were significantly higher than those in NP group(P<0.01). The methylation level at-853 site was higher in EPE group than that in HELLP group(P<0.05). The-595 site showed the unmethylated in EPE, HELLP and APS groups. There were significantly difference between the 3 groups and EPE group(P<0.01).(3)The gene expression of LCHAD mRNA in EPE(0.048±0.005), HELLP(0.045±0.006)and APS(0.044±0.004)groups were significantly lower than NP group(0.076±0.009; P<0.01).(4)The correlation of methylation level and gene expression in all groups: the methylation level at-899,-853,-727,-615 and-579 sites were negatively correlated with gene mRNA expression in EPE group(P<0.05). The methylation level at-899,-853 and-615 sites were negatively correlated with gene mRNA expression in HELLP group(P< 0.05). CONCLUSIONS: The variation of LCHAD DNA methylation of trophoblast cells are found among EPE, HELLP syndrome and APS. The different correlation of LCHAD DNA methylation and gene expression are different in pathological groups. LCHAD DNA methylation of EPE and HELLP syndrome were significantly increased and negatively correlated with LCHAD gene mRNA expression. These results further revealed the molecular basis of long-chain fatty acid oxidation in different preeclampsia and pathological pregnancy.


Asunto(s)
Síndrome Antifosfolípido/genética , Metilación de ADN/genética , Síndrome HELLP/genética , 3-Hidroxiacil-CoA Deshidrogenasa de Cadena Larga/metabolismo , Preeclampsia/genética , Preeclampsia/metabolismo , 3-Hidroxiacil-CoA Deshidrogenasas/genética , Cardiomiopatías , ADN , Ácidos Grasos , Femenino , Expresión Génica , Humanos , Errores Innatos del Metabolismo Lipídico , Miopatías Mitocondriales , Proteína Trifuncional Mitocondrial/deficiencia , Enfermedades del Sistema Nervioso , Oxidación-Reducción , Placenta/metabolismo , Embarazo , ARN Mensajero/genética , Rabdomiólisis , Trofoblastos
4.
Infect Immun ; 83(3): 1104-13, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25561710

RESUMEN

Fusobacterium nucleatum is a common oral anaerobe involved in periodontitis that is known to translocate and cause intrauterine infections. In the oral environment, F. nucleatum adheres to a large diversity of species, facilitating their colonization and creating biological bridges that stabilize the multispecies dental biofilm. Many of these interactions (called coadherences or coaggregations) are galactose sensitive. Galactose-sensitive interactions are also involved in the binding of F. nucleatum to host cells. Hemagglutination of some F. nucleatum strains is also galactose sensitive, suggesting that a single galactose-sensitive adhesin might mediate the interaction of fusobacteria with many partners and targets. In order to identify the fusobacterial galactose-sensitive adhesin, a system for transposon mutagenesis in fusobacteria was created. The mutant library was screened for hemagglutination deficiency, and three clones were isolated. All three clones were found to harbor the transposon in the gene coding for the Fap2 outer membrane autotransporter. The three fap2 mutants failed to show galactose-inhibitable coaggregation with Porphyromonas gingivalis and were defective in cell binding. A fap2 mutant also showed a 2-log reduction in murine placental colonization compared to that of the wild type. Our results suggest that Fap2 is a galactose-sensitive hemagglutinin and adhesin that is likely to play a role in the virulence of fusobacteria.


Asunto(s)
Adhesinas Bacterianas/genética , Proteínas Portadoras/genética , Infecciones por Fusobacterium/microbiología , Fusobacterium nucleatum/genética , Hemaglutininas/genética , Placenta/microbiología , Adhesinas Bacterianas/metabolismo , Animales , Carga Bacteriana , Proteínas Portadoras/metabolismo , Elementos Transponibles de ADN , Femenino , Infecciones por Fusobacterium/patología , Fusobacterium nucleatum/efectos de los fármacos , Fusobacterium nucleatum/metabolismo , Fusobacterium nucleatum/patogenicidad , Galactosa/farmacología , Expresión Génica , Biblioteca de Genes , Pruebas de Hemaglutinación , Hemaglutininas/metabolismo , Ratones , Mutación , Placenta/patología , Embarazo
5.
Adv Dent Res ; 26(1): 47-55, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24736704

RESUMEN

Interrelationships between periodontal infection and systemic conditions such as cardiovascular disease, adverse pregnancy outcomes, and head-and-neck cancer have become increasingly appreciated in recent years. Periodontitis is associated with cardiovascular disease (CVD) and, experimentally, with measures of atherosclerosis and endothelial dysfunction. Periodontal therapy may reduce atherosclerotic changes and improve endothelial function. Preliminary findings suggest a role for the genetic locus ANRIL in the pathobiology of both CVD and periodontitis. Periodontal pathogens induce anticardiolipin in periodontitis patients by molecular mimicry of the serum protein ß-2 glycoprotein I. These antibodies have biological and pathological activities consistent with those reported for other infection-induced antiphospholipid antibodies. Anticardiolipin may explain some of the observed associations between periodontitis and systemic conditions such as CVD and adverse pregnancy outcomes. The oral commensal Fusobacterium nucleatum (Fn) becomes pathogenic on migration to extra-oral sites. Fn infection of the fetal-placental unit has been linked to pregnancy complications, including preterm birth, stillbirth, and early-onset neonatal sepsis. Reagents aimed at inhibiting or resolving inflammatory responses may be used to treat or prevent pregnancy complications due to bacterial infection. Chronic periodontitis may be independently associated with head-and-neck squamous cell carcinoma (HNSCC) through direct toxic effects of bacteria and their products, and/or through indirect effects of inflammation. Additionally, chronic periodontitis may facilitate the acquisition and persistence of oral HPV infection, a recently emerged risk factor for HNSCC.


Asunto(s)
Aterosclerosis/complicaciones , Neoplasias de Cabeza y Cuello/complicaciones , Enfermedades Periodontales/complicaciones , Resultado del Embarazo , Femenino , Humanos , Embarazo
7.
J Periodontol ; 80(4): 535-40, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19335072

RESUMEN

BACKGROUND: Rheumatoid arthritis (RA) and periodontitis are common chronic inflammatory conditions. Recent studies showed a beneficial effect of periodontal treatment on the severity of active RA. This study was undertaken to further examine the effect of non-surgical periodontal treatment on the signs and symptoms of RA in patients treated with or without anti-tumor necrosis factor-alpha (anti-TNF-alpha) medications. The effect of anti-TNF-alpha therapy on periodontitis also was assessed. METHODS: Forty participants diagnosed with moderate/severe RA (under treatment for RA) and severe periodontitis were randomly assigned to receive initial non-surgical periodontal therapy with scaling/root planing and oral hygiene instructions (n = 20) or no periodontal therapy (n = 20). To control RA, all participants had been using disease-modifying anti-rheumatic drugs, and 20 had also been using anti-TNF-alpha before randomization. Probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), gingival index (GI), plaque index (PI), RA disease activity score 28 (DAS28), and erythrocyte sedimentation rate (ESR) were measured at baseline and 6 weeks later. Linear mixed models were used to identify significant differences between subjects who received periodontal treatment and those who did not. RESULTS: Patients receiving periodontal treatment showed a significant decrease in the mean DAS28, ESR (P <0.001), and serum TNF-alpha (P <0.05). There was no statistically significant decrease in these parameters in patients not receiving periodontal treatment. Anti-TNF-alpha therapy resulted in a significant improvement in CAL, PD, BOP, and GI. CONCLUSIONS: Non-surgical periodontal therapy had a beneficial effect on the signs and symptoms of RA, regardless of the medications used to treat this condition. Anti-TNF-alpha therapy without periodontal treatment had no significant effect on the periodontal condition.


Asunto(s)
Artritis Reumatoide/terapia , Periodontitis Crónica/terapia , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adulto , Anciano , Anciano de 80 o más Años , Antirreumáticos/uso terapéutico , Artritis Reumatoide/sangre , Artritis Reumatoide/complicaciones , Periodontitis Crónica/sangre , Periodontitis Crónica/complicaciones , Índice de Placa Dental , Raspado Dental , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Índice Periodontal , Factor Reumatoide/sangre , Índice de Severidad de la Enfermedad , Factor de Necrosis Tumoral alfa/sangre
8.
Zhonghua Er Ke Za Zhi ; 57(1): 46-49, 2019 Jan 02.
Artículo en Zh | MEDLINE | ID: mdl-30630231

RESUMEN

Objective: To investigate the clinical characteristics and risk-factors of traumatic basal ganglia stroke (TBGS) in children. Methods: A retrospective case study was conducted to analyze the clinical and imaging data of 16 children with TBGS in the First Hospital of Jilin University from January 2014 to June 2017. A total of 16 TBGS cases (11 males, 5 females) were diagnosed and the age ranged from 0.5 to 13.0 years. The prognosis of children with TBGS at different ages (≥5 years and<5 years) and with different traumatic stroke (infarction and hemorrhage) were compared. Fisher 's test was used to compare the prognosis of different groups. Results: All cases had clear history of head trauma and varying degrees of limb paralysis after injury, including 4 cases of facial paralysis, 3 cases of consciousness disturbance and 1 case of seizures. Head CT scan of the 16 cases showed 11 cases of ischemic stroke and 5 cases of hemorrhagic stroke. Moreover, scattered calcification was observed in the bilateral basal ganglia point of 8 cases. Neurotrophic treatment, microcirculation improvement and nerve rehabilitations were given according to the clinical and imaging data. One patient was treated with craniotomy and hematoma clearance. Of the 16 cases, 11 cases were restored to normal, while 3 cases developed limb paralysis and 2 cases died. The prognosis of 11 cases of traumatic basal ganglia infarction (10 cases recovered and 1 case remained hemiplegic) was relatively better than that of 5 cases of hemorrhage (1 case recovered, 2 cases remained hemiplegic and 2 cases died) (χ(2)=8.045, P=0.013). In addition, the children younger than 5-year-old (all 8 cases recovered) had a better prognosis than the children older than 5-year-old (8 cases, 3 of whom recovered, 3 cases remained hemiplegia, 2 cases died)(χ(2)=12.121, P<0.01). Conclusions: The anatomical characteristics of basal ganglia and calcification of the lenticulostriate artery are risk-factors for TBGS in children. The prognosis of infarcted children and younger children is relatively better.


Asunto(s)
Accidente Cerebrovascular , Tomografía Computarizada por Rayos X , Adolescente , Ganglios Basales/patología , Calcinosis , Niño , Preescolar , Traumatismos Craneocerebrales , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia
9.
J Mol Biol ; 235(3): 908-25, 1994 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-8289327

RESUMEN

Bacteriophage lambda encodes a site-specific recombination system that promotes the movement of the phage genome into and out of the host bacterial chromosome. The phage-encoded integrase (Int) is composed of 356 amino acid residues and carries out the required strand exchanges by means of a type I topoisomerase activity. Int also contains two distinct DNA-binding domains that interact with two different, specific sequences (arm-type and core-type sites) on DNA. In order to help understand the mechanism of site-specific recombination, we have used a genetic approach to isolate mutants defective in different steps in the recombination reaction. We developed a genetic screen for Int mutants that are defective in catalyzing excisive recombination in vivo. These mutants were screened for proficiency in binding to the P'123 arm-type sites using the bacteriophage P22 challenge-phage assays. In all, 78 such mutants were isolated and the mutational changes mapped and sequenced. These mutants have been further characterized (1) for their ability to bind the P'1 and P'123 arm-type sites and for their ability to form the attL complex in vivo, (2) for negative dominance in vitro, (3) for the presence of type I topoisomerase activity, and (4) for the ability to resolve artificially constructed recombination intermediates. We found that (1) residues in a stretch of 88 amino acids in the middle of the protein may be involved in Int-Int interactions, (2) a region around Arg212 is involved in the catalytic site, (3) residues near the carboxyl terminus play a role in enhancing Int binding to its arm-type sites, possibly by interacting with the small amino-terminal region that has been shown to be responsible for specific recognition of the arm-type sites, and (4) residues at the very carboxyl end of the protein may be involved in modulating the cleavage or religation activities of the Int protein.


Asunto(s)
Bacteriófago lambda/genética , ADN Nucleotidiltransferasas/química , Lisogenia , Recombinación Genética , Proteínas Virales/química , ADN-Topoisomerasas de Tipo I/metabolismo , Integrasas , Mutagénesis , Relación Estructura-Actividad , Especificidad por Sustrato
10.
Adv Appl Microbiol ; 35: 171-94, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2205081

RESUMEN

Levans are natural polymers of the sugar fructose found in many plants and microbial products. Like dextrans, they are formed as an undesirable by-product of sugar juice processing. On the other hand, levans, which can only be produced from sucrose, have potential industrial applications as thickeners and encapsulating agents and could provide additional, valuable products from sugarcane juice. A strain of B. polymyxa (NRRL B-18475) produced a high yield of polysaccharide when grown on sucrose solution. Hydrolysis and subsequent analyses showed the product to consist entirely of D-fructose. 13C-NMR and methylation analyses indicated the products to be a beta(2----6)-linked polymer of fructose, with 12% branching. The polysaccharide has a Mr of approximately 2 million and is readily soluble in water. Levan has not been utilized, but if developed, could be useful in food and other industrial applications.


Asunto(s)
Bacterias/metabolismo , Fructanos , Polisacáridos , Secuencia de Carbohidratos , Fructanos/análisis , Fructanos/biosíntesis , Fructanos/metabolismo , Microbiología Industrial , Datos de Secuencia Molecular , Estructura Molecular , Polisacáridos/análisis , Polisacáridos/biosíntesis , Polisacáridos/metabolismo
11.
J Dent Res ; 92(6): 485-91, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23625375

RESUMEN

The link between oral infections and adverse systemic conditions has attracted much attention in the research community. Several mechanisms have been proposed, including spread of the oral infection due to transient bacteremia resulting in bacterial colonization in extra-oral sites, systemic injury by free toxins of oral pathogens, and systemic inflammation caused by soluble antigens of oral pathogens. Mounting evidence supports a major role of the systemic spread of oral commensals and pathogens to distant body sites causing extra-oral infections and inflammation. We review here the most recent findings on systemic infections and inflammation complicated by oral bacteria, including cardiovascular disease, adverse pregnancy outcomes, rheumatoid arthritis, inflammatory bowel disease and colorectal cancer, respiratory tract infections, and organ inflammations and abscesses. The recently identified virulence mechanisms of oral species Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus mutans, and Campylobacter rectus are also reviewed. A pattern emerges indicating that only select subtype(s) of a given species, e.g., F. nucleatum subspecies animalis and polymorphum and S. mutans non-c serotypes, are prone to extra-oral translocation. These findings advocate the importance of identification and quantification of potential pathogens at the subtype levels for accurate prediction of disease potential.


Asunto(s)
Infecciones Bacterianas/microbiología , Inflamación/microbiología , Metagenoma/fisiología , Boca/microbiología , Bacteriemia/microbiología , Traslocación Bacteriana/fisiología , Humanos , Virulencia
12.
J Dent Res ; 90(3): 289-93, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21041548

RESUMEN

Studies on the link between periodontal disease and adverse pregnancy outcome have gone through several phases. The epidemiological studies predominantly support a positive association between these wide-affecting diseases. During the intervention phase, a few small-scale, single-center studies reported improvement of birth outcome following periodontal treatment, whereas the large-scale multi-center studies did not demonstrate efficacy. Many questions arise with regard to patient population, disease type, and therapy. In addressing these questions, it is crucial that one understands the mechanism underlying the link between these diseases. Two non-mutually exclusive hypotheses exist. In the first, periodontal disease is believed to affect the maternal and fetal immune responses systemically, leading to premature labor. Alternatively, evidence is accumulating that oral bacteria may translocate directly into the pregnant uterus, causing localized inflammation and adverse pregnancy outcome in the presence or absence of clinical periodontitis. The oral-uterine transmission is not limited to the well-recognized periodontal pathogens, but instead may also involve the commensal species. Future studies should investigate these mechanisms, to understand the host susceptibility to oral-uterine transmission. Only when a thorough understanding of the mechanism is achieved can meaningful intervention studies be designed utilizing effective therapies, targeting appropriate populations, and measuring relevant outcomes.


Asunto(s)
Transmisión Vertical de Enfermedad Infecciosa , Periodontitis/complicaciones , Complicaciones Infecciosas del Embarazo , Resultado del Embarazo , Nacimiento Prematuro/etiología , Ensayos Clínicos como Asunto , Femenino , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Intercambio Materno-Fetal , Salud Bucal , Periodontitis/microbiología , Periodontitis/terapia , Embarazo , Complicaciones Infecciosas del Embarazo/microbiología , Complicaciones Infecciosas del Embarazo/terapia , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/prevención & control
13.
Placenta ; 32 Suppl 2: S81-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21227506

RESUMEN

Workshops are an important part of the IFPA annual meeting. At IFPA Meeting 2010 there were twelve themed workshops, six of which are summarized in this report. 1. The immunology workshop focused on normal and pathological functions of the maternal immune system in pregnancy. 2. The transport workshop dealt with regulation of ion and water transport across the syncytiotrophoblast of human placenta. 3. The epigenetics workshop covered DNA methylation and its potential role in regulating gene expression in placental development and disease. 4. The vascular reactivity workshop concentrated on methodological approaches used to study placental vascular function. 5. The workshop on epitheliochorial placentation covered current advances from in vivo and in vitro studies of different domestic species. 6. The proteomics workshop focused on a variety of techniques and procedures necessary for proteomic analysis and how they may be implemented for placental research.


Asunto(s)
Feto/fisiología , Placenta/fisiología , Trofoblastos/fisiología , Animales , Educación , Epigénesis Genética/fisiología , Femenino , Feto/irrigación sanguínea , Feto/citología , Feto/inmunología , Humanos , Transporte Iónico/fisiología , Intercambio Materno-Fetal/fisiología , Placenta/irrigación sanguínea , Placenta/citología , Placenta/inmunología , Placentación/fisiología , Embarazo , Proteómica/métodos , Trofoblastos/citología , Trofoblastos/inmunología
16.
Ultrasound Med Biol ; 35(3): 494-506, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19010589

RESUMEN

To investigate the effects of sonoporation, spatiotemporal evolution of ultrasound-induced changes in intracellular calcium ion concentration ([Ca(2+)](i)) was determined using real-time fura-2AM fluorescence imaging. Monolayers of Chinese hamster ovary (CHO) cells were exposed to a 1-MHz ultrasound tone burst (0.2 s, 0.45 MPa) in the presence of Optison microbubbles. At extracellular [Ca(2+)](o) of 0.9 mM, ultrasound application generated both nonoscillating and oscillating (periods 12 to 30 s) transients (changes of [Ca(2+)](i) in time) with durations of 100-180 s. Immediate [Ca(2+)](i) transients after ultrasound application were induced by ultrasound-mediated microbubble-cell interactions. In some cases, the immediately affected cells did not return to pre-ultrasound equilibrium [Ca(2+)](i) levels, thereby indicating irreversible membrane damage. Spatial evolution of [Ca(2+)](i) in different cells formed a calcium wave that was observed to propagate outward from the immediately affected cells at 7-20 microm/s over a distance >200 microm, causing delayed transients in cells to occur sometimes 60 s or more after ultrasound application. In calcium-free solution, ultrasound-affected cells did not recover, consistent with the requirement of extracellular Ca(2+) for cell membrane recovery subsequent to sonoporation. In summary, ultrasound application in the presence of Optison microbubbles can generate transient [Ca(2+)](i) changes and oscillations at a focal site and in surrounding cells via calcium waves that last longer than the ultrasound duration and spread beyond the focal site. These results demonstrate the complexity of downstream effects of sonoporation beyond the initial pore formation and subsequent diffusion-related transport through the cellular membrane.


Asunto(s)
Calcio/metabolismo , Sonicación/métodos , Albúminas , Animales , Células CHO , Señalización del Calcio/fisiología , Permeabilidad de la Membrana Celular/fisiología , Cricetinae , Cricetulus , Colorantes Fluorescentes , Fluorocarburos , Fura-2/análogos & derivados , Microburbujas , Porosidad
17.
Appl Microbiol ; 29(4): 510-4, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-804853

RESUMEN

Rice straw was fermented with Cellulomonas sp. and Alcaligenes faecalis. Microbial cells and undigested residue, as well as chemically treated (NaOH or NH4OH) and untreated straws, were analyzed for nutrient composition and in vitro digestibility. In a typical fermentation, 75% of the rice straw substrate was digested, and 18.6% of the total substrate weight that disappeared was recovered as microbial protein. The microbial cell fraction was 37% protein and 5% crude fiber; the residue was 12% protein and 45% crude fiber. The microbial protein amino acid profile was similar to alfalfa, except for less cysteins. The microbial cells had more thiamine and less niacin than Torula yeast. In vitro digestibility of the microbial protein was 41.2 to 55%, that of cellulose was 52%.


Asunto(s)
Actinomycetales/metabolismo , Alcaligenes/metabolismo , Alimentación Animal/normas , Celulosa/metabolismo , Actinomycetales/análisis , Alcaligenes/análisis , Aminoácidos/análisis , Alimentación Animal/análisis , Animales , Bacterias/metabolismo , Proteínas Bacterianas/análisis , Cryptococcus/análisis , Cryptococcus/metabolismo , Fermentación , Gases , Medicago sativa/análisis , Oryza , Proteínas de Plantas/análisis , Rumen/microbiología , Vitaminas/análisis
18.
Can J Microbiol ; 21(10): 1464-7, 1975 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-811340

RESUMEN

Nonlinear survivor curves were obtained when spores of Bacillus cereus were heated in physiological saline solution. Curvilinear survivor curves did not appear to be caused by experimental artifacts but by the heterogeneity of spore population with regard to heat resistance.


Asunto(s)
Bacillus cereus , Calor , Adaptación Fisiológica , Bacillus cereus/crecimiento & desarrollo , Recuento de Células , Esporas Bacterianas/crecimiento & desarrollo
19.
Infect Immun ; 65(1): 327-30, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8975933

RESUMEN

Yersinia pseudotuberculosis and Yersinia enterocolitica are closely related human pathogens causing gastroenteritis. Invasin and YadA are two of the most extensively studied virulence factors of the Yersinia genus. Invasin is the primary invasion factor encoded by the inv gene on the chromosome and is required for the penetration of the epithelial cells. YadA is encoded by the yadA gene on the 70-kb virulence plasmid and has multiple functions. Previous studies indicate that an inv yadA double mutant of Y. enterocolitica is avirulent while an inv yadA mutant of Y. pseudotuberculosis is hypervirulent. In this study, we investigated this unexpected difference. New constructs of the inv yadA mutants of Y. pseudotuberculosis were made and tested in mice. These new constructs were not hypervirulent; rather, they maintained the same virulence as the wild-type strain. Further examination of the inv mutant used for the previous study revealed that it carries an aberrant inv phenotype and has an altered outer membrane profile and an altered colony morphology. Therefore, the mutants used previously were not isogenic to the parental wild-type strain, which may in part account for the difference in the results obtained.


Asunto(s)
Adhesinas Bacterianas/genética , Proteínas Bacterianas/genética , Mutación , Yersinia pseudotuberculosis/genética , Yersinia pseudotuberculosis/patogenicidad , Animales , Proteínas de la Membrana Bacteriana Externa/análisis , Células CHO , Cricetinae , Estudios de Evaluación como Asunto , Femenino , Dosificación Letal Mediana , Ratones , Ratones Endogámicos BALB C , Fenotipo , Virulencia/genética
20.
Biotechnol Bioeng ; 25(8): 2077-84, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18551552

RESUMEN

Production of enzymes in the cellulolytic complex was determined in culture filtrates of six fungal isolates grown on chemically treated or gamma-irradiated bagasse. The enzymatic activities of the filtrates were determined by measurement of glucose release from cotton, filter paper, carboxymethylcellulose, cellobiose, and cellobiose octaacetate. Cultures grown on base-treated and gamma-irradiated plus acid-treated bagasse provided culture filtrates with the highest enzymatic activities whereas alpha-cellulose, untreated, and acid-treated bagasse were the poorest substrates for enzyme production. Filtrates of Trichoderma reesei QM 9414 yielded the highest cellulolytic activity in all test media. The largest accumulation of fungal-derived, extracellular protein was observed in media containing gamma-irradiated bagasse as the carbon substrate.

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