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1.
Artigo em Espanhol | CUMED | ID: cum-79362

RESUMO

Introducción: La infertilidad ha aumentado a nivel mundial como consecuencia del incremento de las infecciones de transmisión sexual y la enfermedad inflamatoria pélvica producidas fundamentalmente por Chlamydia trachomatis.Objetivo: Describir la relación existente entre la Chlamydia trachomatis y sus daños y consecuencias en mujeres infértiles.Métodos: Se estudiaron 552 mujeres, con diagnóstico de infertilidad y se selecciona una muestra de 175, con diagnóstico de infección por Chlamydia trachomatis.Resultados: Las mujeres en el estudio tenían una escolaridad media superior. La mayoría de las mujeres a pesar de padecer una infección por Chlamydia trachomatis no presentaron daño a órganos reproductores; y en las que sí, predominó la obstrucción tubaria bilateral. En los casos en que se diagnosticó daño al cuello uterino predominó la cervicitis.Conclusiones: La mayoría de las mujeres infértiles con infección por Chlamydia trachomatis eran adultas jóvenes con nivel escolar medio superior, con una infertilidad secundaria y sin daños estructurales en las trompas de Falopio y el cérvix uterino. Existe relación entre la Chlamydia trachomatis y la afección a las trompas de Falopio y el cérvix uterino.[AU]


Assuntos
Humanos , Infertilidade , Psitacose , Genitália
2.
Sci Rep ; 9(1): 8863, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222084

RESUMO

Invasive fungal infections (IFIs) are the most frequent cause of morbidity and mortality in immunocompromised children. Voriconazole is the first-line antifungal choice in the treatment of IFIs like aspergillosis. Voriconazole pharmacokinetics vary widely among patients and voriconazole is metabolized mainly in the liver by the CYP2C19 enzyme, which is highly polymorphic. The CYP2C19*17 allele is characterized by the presence of four single nucleotide polymorphisms expressing an ultra-rapid enzyme phenotype with an accelerated voriconazole metabolism, is associated with low (sub-therapeutic) plasma levels in patients treated with the standard dose. Considering that in our center a high percentage of children have sub-therapeutic levels of voriconazole when treated with standard doses, we sought to determine the frequency of the CYP2C19*17 polymorphism (rs12248560) in a Chilean population and determine the association between voriconazole concentrations and the rs12248560 variant in immunocompromised children. First, we evaluated the frequency of the rs12248560 variant in a group of 232 healthy Chilean children, and we found that 180 children (77.6%) were non-carriers of the rs12248560 variant, 49 children (21.1%) were heterozygous carriers for rs12248560 variant and only 3 children (1.3%) were homozygous carriers for rs12248560 variant, obtaining an allelic frequency of 12% for variant in a Chilean population. To determine the association between voriconazole concentrations and the rs12248560 variant, we analyzed voriconazole plasma concentrations in a second group of 33 children treated with voriconazole. In these patients, carriers of the rs12248560 variant presented significantly lower voriconazole plasma concentrations than non-carriers (p = 0,011). In this study, we show the presence of the rs12248560 variant in a Chilean population and its accelerating effect on the pharmacokinetics of voriconazole in pediatric patients. From these data, it would be advisable to consider the variant of the patient prior to calculating the dosage of voriconazole.


Assuntos
Antifúngicos/farmacocinética , Citocromo P-450 CYP2C19/genética , Hospedeiro Imunocomprometido/genética , Infecções Fúngicas Invasivas/tratamento farmacológico , Voriconazol/farmacocinética , Antifúngicos/sangue , Criança , Pré-Escolar , Chile , Feminino , Humanos , Masculino , Polimorfismo Genético , Voriconazol/sangue
3.
Med Oral Patol Oral Cir Bucal ; 24(1): e8-e11, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30573716

RESUMO

BACKGROUND: The aim of this study was to record and analyze all DDAs associated to dilacerated teeth in patients attending the clinics of the Postgraduate Division, Facultad de Odontología, UNAM in Mexico City. MATERIAL AND METHODS: Orthopantomograms from all patients seeking for stomatological attention in our institution were reviewed and those cases of dilaceration were separated. Age, gender, diagnosis, location, involved teeth and associated DDAs were recorded and analyzed. RESULTS: From 6,340 patients, 99 (1.6%) harbored 125 dilacerated teeth. Of them, 45 (45.5%) showed one or more DDAs. The most frequently detected DDAs were hypodontia, enamel pearls, taurodontism and microdontia. CONCLUSIONS: 45.5% is a very high proportion of DDAs in patients with dilacerated roots. Findings from this study strongly suggest that patients with dilacerated teeth should be carefully screened since many of them could present other DDAs. Simultaneous occurrence of dilaceration and DDAs suggests synchronic developmental defects during dental growth.


Assuntos
Odontogênese , Anormalidades Dentárias/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Clin Microbiol Infect ; 23(3): 173-178, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27856269

RESUMO

OBJECTIVES: To determine efficacy and safety of withholding antimicrobials in children with cancer, fever and neutropenia (FN) with a demonstrated respiratory viral infection. METHODS: Prospective, multicentre, randomized study in children presenting with FN at five hospitals in Santiago, Chile, evaluated at admission for diagnosis of bacterial and viral pathogens including PCR-microarray for 17 respiratory viruses. Children positive for a respiratory virus, negative for a bacterial pathogen and with a favourable evolution after 48 h of antimicrobial therapy were randomized to either maintain or withhold antimicrobials. Primary endpoint was percentage of episodes with uneventful resolution. Secondary endpoints were days of fever/hospitalization, bacterial infection, sepsis, admission to paediatric intensive care unit (PICU) and death. RESULTS: A total of 319 of 951 children with FN episodes recruited between July 2012 and December 2015 had a respiratory virus as a unique identified microorganism, of which 176 were randomized, 92 to maintain antimicrobials and 84 to withdraw. Median duration of antimicrobial use was 7 days (range 7-9 days) versus 3 days (range 3-4 days), with similar frequency of uneventful resolution (89/92 (97%) and 80/84 (95%), respectively, not significant; OR 1.48; 95% CI 0.32-6.83, p 0.61), and similar number of days of fever (2 versus 1), days of hospitalization (6 versus 6) and bacterial infections throughout the episode (2%-1%), with one case of sepsis requiring admission to PICU in the group that maintained antimicrobials, without any deaths. CONCLUSIONS: The reduction of antimicrobials in children with FN and respiratory viral infections, based on clinical and microbiological/molecular diagnostic criteria, should favour the adoption of evidence-based management strategies in this population.


Assuntos
Anti-Infecciosos/administração & dosagem , Neutropenia Febril/tratamento farmacológico , Infecções Respiratórias/tratamento farmacológico , Viroses/tratamento farmacológico , Suspensão de Tratamento , Adolescente , Criança , Pré-Escolar , Chile , Hospitais , Humanos , Lactente , Recém-Nascido , Masculino , Neoplasias/complicações , Estudos Prospectivos , Resultado do Tratamento
5.
Food Chem ; 171: 266-71, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25308668

RESUMO

Recent studies have shown that it should be possible to control lipid bioavailability through food structural approaches. Nevertheless, the gastrointestinal-tract physiological conditions must also be considered. To get a better understanding of this phenomenon, we evaluated the effect of emulsification, as well as the use of sodium caseinate or chitosan, on the postprandial bioavailability of interesterified-lipids in O/W emulsions after oral gastric feeding Sprague-Dawley rats. We verified that emulsification may increase lipid absorption, as determined after feeding sodium-caseinate emulsions. However, this result could not be generalised. Interesterified-lipids that were emulsified with chitosan were equally absorbed as those contained in non-emulsified interesterified-lipids/distilled-water blends.


Assuntos
Biomarcadores/sangue , Caseínas/química , Quitosana/química , Emulsões/química , Lipídeos/química , Animais , Disponibilidade Biológica , Masculino , Ciências da Nutrição , Período Pós-Prandial , Ratos , Ratos Sprague-Dawley , Reologia , Água/química
6.
Forensic Sci Int Genet ; 9: 47-54, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24528579

RESUMO

There has been very little work published on the variation of reporting practices of mixtures between laboratories, but it has been previously demonstrated that there is little consistency. This is because there is no current uniformity of practice, so different laboratories will operate using different rules. The interpretation of mixtures is not solely a matter of using some software to provide 'an answer'. An assessment of a case will usually begin with a consideration of the circumstances of a crime. Assumptions made about the numbers of contributors follow from an examination of the electropherogram(s)--and these may differ between the prosecution and the defence hypotheses. There may be a necessity to evaluate several sets of hypotheses for any given case if the circumstances are uncertain. Once the hypotheses are formulated, the mathematical analysis is complex and can only be accomplished by the use of specialist software. In order to obtain meaningful results, it is essential that scientists are trained, not only in the use of the software, but also in the methodology to understand the likelihood ratio concept that is used. The Euroforgen-NoE initiative has developed a training course that utilizes the LRmix program to carry out the calculations. This software encompasses the recommendations of the ISFG DNA commissions on mixture interpretation and is able to interpret samples that may come from two or more contributors and may also be partial profiles. Recently, eighteen different laboratories were trained in the methodology. Afterwards they were asked to independently analyze two different cases with partial mixture DNA evidence and to write a statement court-report. We show that by introducing a structured training programme, it is possible to demonstrate, for the first time, that a high degree of standardization, leading to uniformity of results can be achieved by participating laboratories.


Assuntos
Impressões Digitais de DNA/normas , Laboratórios/normas , Funções Verossimilhança , Software , Europa (Continente) , Humanos , Estatística como Assunto/educação
7.
Tech Coloproctol ; 18(2): 173-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23686679

RESUMO

BACKGROUND: Surgical management of complete rectal prolapse is challenging. We present our results with the novel technique stapled transanal longitudinal posterior proctectomy (STALPP) in patients with complete rectal prolapse. METHODS: We performed a retrospective study in two hospitals from January 2005 to December 2012. Twenty-one patients with complete rectal prolapse were included. In all patients, STALPP was performed. The study variables were operative time, intraoperative bleeding, number of cartridges used, length of rectum prolapsed through the anus, length of rectal wall resected, length of hospital stay and preoperative and postoperative Wexner continence score and manometric measurement of anal canal resting tone and squeeze pressure. RESULTS: The median length of prolapsed tissue was 13 cm; the mean Wexner score in the preoperative and postoperative period was 15.95 and 4.95, respectively (p = 0.025). The mean resting tone improved from 23.3 to 32.85 mmHg postoperatively (p = 0.03), as did maximal squeeze pressure from 31 to 62.7 mmHg (p = 0.003). Median operative time was 65 min; median intraoperative bleeding was 12 ml; there was no postoperative bleeding, and no reinterventions were required. The median number of cartridges used was 4. The median length of resected wall in the right posterolateral sector was 8 and 6 cm in the left. The median length of hospital stay was 4 days, and the mean follow-up period was 2 years. No mortality was reported. CONCLUSIONS: Stapled transanal longitudinal posterior proctectomy is a safe and feasible surgical alternative for patients with complete rectal prolapse.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Prolapso Retal/cirurgia , Grampeamento Cirúrgico , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal/fisiopatologia , Perda Sanguínea Cirúrgica , Incontinência Fecal/etiologia , Feminino , Humanos , Tempo de Internação , Masculino , Manometria , Pessoa de Meia-Idade , Duração da Cirurgia , Prolapso Retal/complicações , Prolapso Retal/patologia , Estudos Retrospectivos , Adulto Jovem
8.
Food Chem ; 139(1-4): 571-7, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23561147

RESUMO

Fatty acid (FA) profile is a critical factor in the nutritional properties of fats, but, stereochemistry may also play a fundamental role in the rate and extent to which FAs are absorbed and become available. To better understand this phenomenon, we evaluated the bioavailability of FAs in linseed-oil and palm-stearin blends compared to their interesterified mix, using a sn-1,3 stereospecific lipase, to determine if there was any difference in terms of FA availability when using this technology. Test meals were fed through an intragastric feeding tube on Sprague-Dawley male rats after 18 h fasting. Postprandial blood samples were collected after meal or physiological serum (control) administration and the FA profile of plasma lipids was determined. Results showed that modification of the melting profile through interesterification, without altering the bioavailability determined by sn-2 stereochemistry, could delay lipid absorption at the beginning, but had no effect on total lipid absorption.


Assuntos
Ácidos Graxos/metabolismo , Lipídeos/química , Animais , Disponibilidade Biológica , Esterificação , Jejum , Ácidos Graxos/química , Metabolismo dos Lipídeos , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley
9.
Nat Prod Res ; 27(17): 1594-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23098219

RESUMO

A phytochemical investigation of the stem bark of Diospyros cuneata (Ebenaceae) together with in vitro cytotoxic evaluation of the pure compounds in four human cancer cell lines KB, Hep-2, HeLa and SiHa led to the isolation of plumbagin, elliptinone, lupeol, atraric acid methyl ester, maritinone, betulin and betulinaldehyde. The structural determination of the compounds was established by nuclear magnetic resonance, electron ionisation mass spectrometric analysis as well as comparison with data from the literature. Plumbagin exhibited a potent cytotoxic activity (CC50 = 3.56 µg mL(-1)) against KB cell lines whereas maritinone displayed cytotoxic activity against Hep-2 (CC50 = 17.30 µg mL(-1)), cervical cancer (CC50 = 21.10 µg mL(-1)) and the KB cell lines (CC50 = 20.30 µg mL(-1)). This is the first report on a phytochemical and biological evaluation of D. cuneata.


Assuntos
Diospyros/química , Casca de Planta/química , Caules de Planta/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Naftoquinonas/química , Triterpenos Pentacíclicos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Triterpenos/química
10.
Nat Prod Res ; 27(13): 1174-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22963268

RESUMO

From the hexane extract of stem bark of Diospyros anisandra was isolated a new plumbagin dimer, epoxide of zeylanone, along with 14 known compounds, including seven naphthoquinones, four triterpenoids and three sesquiterpenoids. The structures were elucidated by the application of IR, UV, MS, 1D- and 2D-NMR spectroscopic analysis and by comparison with literature data.


Assuntos
Diospyros/química , Naftoquinonas/química , Estrutura Molecular , Casca de Planta/química , Caules de Planta/química
11.
Vet Parasitol ; 189(2-4): 284-90, 2012 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-22579554

RESUMO

The in vivo anthelmintic (AH) activity of the ethanolic extract from leaves of Phytolacca icosandra was evaluated in goats artificially infected with Haemonchus contortus. Parasite naïve goats were artificially infected with 3000 H. contortus infective larvae per animal. Once the infection was patent (day 28 post-infection) all the animals were sampled to determine the faecal egg counts (FEC) for five consecutive days. Two groups of animals were formed balanced for their FEC and body-weight (BW) (n=6/group): the non-treated control group and the treated group in which goats were individually administered with the ethanolic extract of P. icosandra. The extract was administered orally using gelatin capsules (250 mg/kg BW) which were dosed on two consecutive days using a pill-dispenser. Faecal samples were collected from each animal from the day of dosage (Day 0) on a daily basis to determine the number of eggs per gram of feces (EPG) for 15 days post-treatment (PT). The FEC of the two groups were compared using the repeated measures analyses of variance using the log transformed data Ln (FEC+1). The presence of saponins, coumarins, flavonoids, steroids and terpenoids were detected by standard methodologies in the extract. The P. icosandra ethanolic extract was further analyzed by gas chromatography (GC) coupled to a mass spectrometry (GC-MS). A significant reduction in FEC was observed in the treated group compared to the control from day 7 until day 15 PT (P<0.05). The highest percentage reduction (72%) was found on day 11 PT. No adverse reactions were observed in all treated animals for the entire trial. The GC-MS analysis of the organic extracts revealed the presence of three fatty acids as compounds with highest abundance. The three compounds that were identified by their mass fragmentation patterns were: 2-Pentadecanone, 6, 10, 14-trimethyl (RT 10.3 min), Pentadecanoic acid, 14-methyl-, methyl ester (RT 10.8 min) and Hexadecanoic acid, ethyl ester (RT 11.2 min). It is concluded that the P. icosandra ethanolic extract obtained from leaves showed in vivo anthelmintic activity against H. contortus when administered orally to goats at a dose of 250 mg/kg BW on two consecutive days. The dose used did not cause any negative effects on the health of goats.


Assuntos
Anti-Helmínticos/uso terapêutico , Doenças das Cabras/parasitologia , Hemoncose/tratamento farmacológico , Haemonchus/efeitos dos fármacos , Phytolacca/química , Extratos Vegetais/farmacologia , Animais , Fezes/parasitologia , Doenças das Cabras/tratamento farmacológico , Cabras , Contagem de Ovos de Parasitas , Extratos Vegetais/química , Folhas de Planta/química , Fatores de Tempo
12.
Vet Parasitol ; 179(1-3): 100-6, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21439732

RESUMO

The development of anthelmintic resistance has impacted on the success of conventional anthelmintics (AH) for the control of gastrointestinal nematodes in grazing/browsing sheep and goats. Medicinal plants from the traditional herbolary in Mexico may provide new candidates that can be explored as alternative sources of AHs for ruminants. This study evaluated the leaf extracts derived from Phytolacca icosandra against infective L(3) larvae and eggs from Haemonchus contortus collected from sheep. Three extracts of different polarities were obtained from the leaf plants using ethanol, n-hexane and dichloromethane as the solvents. The effectiveness of the in vitro AH activity of the plant extracts was evaluated using larval migration inhibition (LMI) and egg hatch (EHA) assays. For the LMI assays, the ethanolic extract of P. icosandra showed 55.4% inhibition of larval migration at 2mg/mL (p<0.05). The dichloromethane extract of P. icosandra showed 67.1% inhibition of migration at 3mg/mL (p<0.05) and a dose-dependent response with an LD(50) of 0.90 mg/mL. The n-hexane extract failed to show inhibition of larval migration at any concentration explored. In the EHA for the ethanol extract, the lowest concentration tested (0.15 mg/mL) resulted in inhibition of egg hatching greater than 72.6%. Therefore, the LD(50) could not be calculated for this extract. The LD(50) of the dichloromethane extract of P. icosandra was 0. 28 mg/mL. An egg hatch inhibition greater than 90% was observed with both the ethanolic and dichloromethane extracts when using a concentration of 0.90 mg/mL or higher. The n-hexane extract failed to show egg hatch inhibition at any concentration tested. The AH activity reported for P. icosandra could be attributable to the flavonoids, steroids, terpenoids, coumarins and/or saponins that were present in the ethanolic and dichloromethane extracts. A combination of more than one component may also explain the observed AH activity against the H. contortus life stages that were evaluated. In conclusion, the ethanolic and dichloromethane extracts of P. icosandra showed clear in vitro AH activity against the H. contortus eggs and the L(3) larvae. However, the hexanic extract of the plant leaves failed to show any in vitro AH activity.


Assuntos
Haemonchus/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Phytolacca/química , Extratos Vegetais/farmacologia , Animais , Larva/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Extratos Vegetais/química
13.
J Mech Behav Biomed Mater ; 3(8): 640-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20826372

RESUMO

The micromechanical behavior of lyophilized glutaraldehyde bovine pericardium undergoing uniaxial tension was studied by digital image correlation. The experiments were conducted simultaneously at macromechanical and micromechanical levels, to correlate the mechanical response of this biomaterial at different scales. From the experiments, displacement and force data were acquired; in addition, an image sequence of each sample surface was registered with a high-definition camera. With the images, it was possible to obtain the vector displacement field between pairs of images and then the in-plane strain was calculated. The secant and final moduli of this material were obtained at macromechanical and micromechanical levels. A good agreement between the micro and macro moduli was observed. This analysis is a useful alternative technique for studying this biomaterial when local properties are needed for medical applications.


Assuntos
Glutaral/farmacologia , Pericárdio/efeitos dos fármacos , Estresse Mecânico , Animais , Fenômenos Biomecânicos , Bovinos , Liofilização , Técnicas In Vitro , Imagem Molecular , Pericárdio/fisiologia
14.
J Oral Pathol Med ; 39(9): 709-14, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20738751

RESUMO

Excessive fluoride ingestion has been identified as a risk factor for fluorosis and oxidative stress. The oxidative stress results from the loss of equilibrium between oxidative and antioxidative mechanisms that can produce kinase activation, mitochondrial disturbance and DNA fragmentation, resulting in apoptosis. Actually many people are exposed to no-adverted fluoride consumption in acute or chronic way. The aim of this study was to determine the effect of sodium fluoride on first molar germ in relation to its effect on antioxidative enzymes immunoexpression and apoptosis. Thirty first molar germs from 1-day-old Balb/c mice were cultured for 24 h with sodium fluoride (0 mM, 1 mM and 5 mM). Immunoexpression determination of CuZnSod, MnSod, catalase, Bax, Bid, caspase 8, caspase 9, caspase 3 and TUNEL assay were performed. Cellular disorganization in ameloblast and odontoblast-papilla zones was observed. CuZnSod and MnSod immunoexpression decrease in experimental groups. Caspase 8, caspase 3, Bax, Bid increase expression and more TUNEL positive cells in both experimental groups than control, suggest that apoptosis induced by fluoride is related to oxidative stress due to reduction of the enzymatic antioxidant.


Assuntos
Apoptose , Cariostáticos/toxicidade , Odontogênese/efeitos dos fármacos , Estresse Oxidativo , Fluoreto de Sódio/toxicidade , Germe de Dente/efeitos dos fármacos , Ameloblastos/metabolismo , Animais , Apoptose/fisiologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/biossíntese , Caspases/biossíntese , Catalase/biossíntese , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/biossíntese , Germe de Dente/enzimologia , Proteína X Associada a bcl-2/biossíntese
15.
Epidemiol Infect ; 138(4): 525-33, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19765332

RESUMO

Most of the multiplex PCR (mPCR) used to identify Shigella do not discriminate between Shigella species or serotypes. We designed a mPCR to differentiate between S. flexneri and S. sonnei strains based on the detection of markers associated with the she pathogenicity island described in Shigella. In addition, specific primers were included to detect the Shigella virulence determinants ShET-1 and ShET-2 enterotoxin genes. The analysis of 304 Shigella strains from Chile and 79 Shigella strains from other geographic locations indicated that the mPCR described here detected all Shigella species and specifically differentiated S. flexneri and S. sonnei. The technique was sensitive, reproducible, specific and simple to perform, providing a new tool with the potential to be employed for epidemiological and diagnostic purposes.


Assuntos
Proteínas de Bactérias/genética , Técnicas Bacteriológicas/métodos , Disenteria Bacilar/microbiologia , Reação em Cadeia da Polimerase/métodos , Shigella flexneri/isolamento & purificação , Shigella sonnei/isolamento & purificação , Fatores de Virulência/genética , Criança , Pré-Escolar , Chile , DNA Bacteriano/genética , Disenteria Bacilar/diagnóstico , Enterotoxinas/genética , Ilhas Genômicas , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Shigella flexneri/classificação , Shigella flexneri/genética , Shigella sonnei/classificação , Shigella sonnei/genética
16.
Chem Phys Lipids ; 158(2): 110-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19428355

RESUMO

This study analyzed the chemical and physical properties of a biosurfactant synthesized by Rhodococcus sp. 51T7. The biosurfactant was a trehalose tetraester (THL) consisting of six components: one major and five minor. The hydrophobic moieties ranged in size from 9 to 11 carbons. The critical micelle concentration (CMC) was 0.037g L(-1) and the interfacial tension against hexadecane was 5mN m(-1). At pH 7.4 the glycolipid CMC/critical aggregation concentration (CAC) was 0.05g L(-1) and at pH 4 it was 0.034g L(-1). A phase diagram revealed effective emulsification with water and paraffin or isopropyl myristate. A composition of 11.3-7.5-81.8 (isopropyl myristate-THL-W) was stable for at least 3 months. The HLB was 11 and the phase behaviour of the glycolipid revealed the formation of lamellar and hexagonal liquid-crystalline textures.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Glicolipídeos/análise , Glicolipídeos/toxicidade , Rhodococcus/química , Trealose/análise , Trealose/toxicidade , Animais , Linhagem Celular , Emulsões/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Genes Bacterianos , Genes de RNAr , Glicolipídeos/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos , Micelas , Concentração Osmolar , Transição de Fase , Rhodococcus/genética , Trealose/isolamento & purificação
17.
Artigo em Inglês | MEDLINE | ID: mdl-16859968

RESUMO

In this work, the synthesis of new materials formed from metallic phthalocyanines (Pcs) and double potassium salt from 1,8-dihydroxianthraquinone is reported. The newly synthesized materials were characterized by scanning electron microscope (SEM), atomic force microscopy (AFM), infrared (IR) and Ultraviolet-visible (UV-vis) spectroscopy. The powder and thin-film samples of the synthesized materials, deposited by vacuum thermal evaporation, show the same intra-molecular bonds as in the IR spectroscopy studies, which suggests that the thermal evaporation process does not alter these bonds. The effect of temperature on conductivity and electrical conduction mechanism was measured in the thin films (approximately 137 nm thickness). They showed a semiconductor-like behaviour with an optical activation energy arising from indirect transitions of 2.15, 2.13 and 3.6eV for the C(46)H(22)N(8)O(4)KFe, C(46)H(22)N(8)O(4)KPb and C(46)H(22)N(8)O(4)KCo thin films.


Assuntos
Condutividade Elétrica , Metais/química , Compostos Organometálicos/química , Temperatura , Cobalto/química , Ferro/química , Chumbo/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Vácuo , Volatilização
18.
Forensic Sci Int ; 168(1): 42-56, 2007 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-16899347

RESUMO

The mitochondrial DNA (mtDNA) working group of the GEP-ISFG (Spanish and Portuguese Group of the International Society for Forensic Genetics) carried out an inter-laboratory exercise consisting of the analysis of mtDNA sequencing patterns in mixed stains (saliva/semen and blood/semen). Mixtures were prepared with saliva or blood from a female donor and three different semen dilutions (pure, 1:10 and 1:20) in order to simulate forensic casework. All labs extracted the DNA by preferential lysis and amplified and sequenced the first mtDNA hypervariable region (HVS-I). Autosomal and Y-STR markers were also analysed in order to compare nuclear and mitochondrial results from the same DNA extracts. A mixed stain prepared using semen from a vasectomized individual was also analysed. The results were reasonably consistent among labs for the first fractions but not for the second ones, for which some laboratories reported contamination problems. In the first fractions, both the female and male haplotypes were generally detected in those samples prepared with undiluted semen. In contrast, most of the mixtures prepared with diluted semen only yielded the female haplotype, suggesting that the mtDNA copy number per cell is smaller in semen than in saliva or blood. Although the detection level of the male component decreased in accordance with the degree of semen dilution, it was found that the loss of signal was not consistently uniform throughout each electropherogram. Moreover, differences between mixtures prepared from different donors and different body fluids were also observed. We conclude that the particular characteristics of each mixed stain can deeply influence the interpretation of the mtDNA evidence in forensic mixtures (leading in some cases to false exclusions). In this sense, the implementation of preliminary tests with the aim of identifying the fluids involved in the mixture is an essential tool. In addition, in order to prevent incorrect conclusions in the interpretation of electropherograms we strongly recommend: (i) the use of additional sequencing primers to confirm the sequencing results and (ii) interpreting the results to the light of the phylogenetic perspective.


Assuntos
Impressões Digitais de DNA , DNA Mitocondrial/genética , Análise de Sequência de DNA , Sangue , Contagem de Células , Cromossomos Humanos Y , Técnicas de Laboratório Clínico , Feminino , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase , Controle de Qualidade , Saliva , Sêmen , Espermatozoides/citologia , Sequências de Repetição em Tandem , Vasectomia
19.
Hum Mutat ; 26(6): 520-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16220553

RESUMO

A collaborative work was carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG) to estimate Y-STR mutation rates. Seventeen Y chromosome STR loci (DYS19, DYS385, DYS389I and II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS460, DYS461, DYS635 [GATA C4], GATA H4, and GATA A10) were analyzed in a sample of 3,026 father/son pairs. Among 27,029 allele transfers, 54 mutations were observed, with an overall mutation rate across the 17 loci of 1.998 x 10(-3) (95% CI, 1.501 x 10(-3) to 2.606 x 10(-3)). With just one exception, all of the mutations were single-step, and they were observed only once per gametogenesis. Repeat gains were more frequent than losses, longer alleles were found to be more mutable, and the mutation rate seemed to increase with the father's age. Hum Mutat 26(6), 520-528, 2005. (c) 2005 Wiley-Liss, Inc.


Assuntos
Cromossomos Humanos Y/genética , Repetições de Microssatélites/genética , Mutação , Fatores Etários , Alelos , Sequência de Bases , Análise Mutacional de DNA , Frequência do Gene , Marcadores Genéticos , Humanos , Masculino , Dados de Sequência Molecular
20.
Epidemiol Infect ; 133(1): 81-6, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15724714

RESUMO

A total of 162 clinical isolates of Shigella collected from children in a semi-rural community of Chile were examined for the presence of genetic determinants of resistance to ampicillin, chloramphenicol, tetracycline, and trimethoprim. Ampicillin resistance was most frequently associated with the presence of bla(OXA) in S. flexneri and with bla(TEM) in S. sonnei. The bla(OXA) gene but not bla(TEM) was located in class 1 integrons. The dhfrIa gene encoding for resistance to trimethoprim was associated to class 2 integrons and detected exclusively in S. flexneri, whereas dhfrIIIc was found in all S. sonnei strains and in 10% of the S. flexneri isolates. Cat, coding for choramphenicol resistance, and bla(OXA) genes were located in the chromosome in all cases, whereas tetA gene, coding for tetracycline resistance, and bla(TEM), dhfrIa and dhfrIIIc genes were found either in the chromosome or in conjugative plasmids. Our results show a heterogenous distribution of antibiotic-resistance determinants between S. flexneri and S. sonnei.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Disenteria Bacilar/epidemiologia , Disenteria Bacilar/microbiologia , Shigella flexneri/genética , Shigella sonnei/genética , Southern Blotting , Criança , Chile/epidemiologia , Feminino , Humanos , Masculino , Plasmídeos/genética , Reação em Cadeia da Polimerase , População Rural , Shigella flexneri/efeitos dos fármacos , Shigella flexneri/isolamento & purificação , Shigella sonnei/efeitos dos fármacos , Shigella sonnei/isolamento & purificação
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