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1.
Biol Res ; 55(1): 9, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236417

RESUMO

BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans. This pathogen activates multiple regulatory mechanisms in response to stress, and cobalamin biosynthesis might have a potential role in bacterial protection. Low temperature is a strategy used in the food industry to control bacteria proliferation; however, L. monocytogenes can grow in cold temperatures and overcome different stress conditions. In this study we selected L. monocytogenes List2-2, a strain with high tolerance to the combination of low temperature + copper, to understand whether the cobalamin biosynthesis pathway is part of the tolerance mechanism to this stress condition. For this, we characterized the transcription level of three cobalamin biosynthesis-related genes (cbiP, cbiB, and cysG) and the eutV gene, a transcriptional regulator encoding gene involved in ethanolamine metabolism, in L. monocytogenes strain List2-2 growing simultaneously under two environmental stressors: low temperature (8 °C) + copper (0.5 mM of CuSO4 × 5H2O). In addition, the gene cbiP, which encodes an essential cobyric acid synthase required in the cobalamin pathway, was deleted by homologous recombination to evaluate the impact of this gene in L. monocytogenes tolerance to a low temperature (8 °C) + different copper concentrations. RESULTS: By analyzing the KEGG pathway database, twenty-two genes were involved in the cobalamin biosynthesis pathway in L. monocytogenes List2-2. The expression of genes cbiP, cbiB, and cysG, and eutV increased 6 h after the exposure to low temperature + copper. The cobalamin cbiP mutant strain List2-2ΔcbiP showed less tolerance to low temperature + copper (3 mM) than the wild-type L. monocytogenes List2-2. The addition of cyanocobalamin (5 nM) to the medium reverted the phenotype observed in List2-2ΔcbiP. CONCLUSION: These results indicate that cobalamin biosynthesis is necessary for L. monocytogenes growth under stress and that the cbiP gene may play a role in the survival and growth of L. monocytogenes List2-2 at low temperature + copper.


Assuntos
Listeria monocytogenes , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Temperatura Baixa , Cobre , Humanos , Listeria monocytogenes/genética , Temperatura , Vitamina B 12/genética , Vitamina B 12/metabolismo
2.
J Phys Chem A ; 117(25): 5354-64, 2013 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-23706045

RESUMO

A theoretical investigation using density functional theory (DFT) has been carried out in order to understand the molecular mechanism of dihydrogen activation by means of transition metal dioxides MO2 (M = Ti, Zr, and Hf) according to the following reaction: MO2 + H2 → MO + H2O. B3LYP/6-311++G(2df,2pd)/SDD methodology was employed considering two possible reaction pathways. As the first step hydrogen activation by M═O bonds yields to metal-oxo hydride intermediates O═MH(OH). This process is spontaneous for all metal dioxides, and the stability of the O═MH(OH) species depends on the transition metal center. Subsequently, the reaction mechanism splits into two paths: the first one takes place passing through the M(OH)2 intermediates yielding to products, whereas the second one corresponds to direct formation of the product complex OM(H2O). A two-state reactivity mechanism was found for the TiO2 system, whereas for ZrO2 and HfO2 no spin-crossing processes were observed. This is confirmed by CASSCF/CASPT2 calculations for ZrO2 that lead to the correct ordering of electronic states not found by DFT. The results obtained in the present paper for MO2 molecules are consistent with the observed reactivity on surfaces.

3.
J Comput Chem ; 33(7): 748-56, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22183786

RESUMO

We analyze the behavior of the energy profile of the ring-closure process for the transformation of (3Z,5Z)-octa-1,3,5,7-tetraene 5 to (1Z,3Z,5Z)-cycloocta-1,3,5-triene 6 through a combination of electron localization function (ELF) and catastrophe theory (CT). From this analysis, concepts such as bond breaking/forming processes, formation/annihilation of lone pairs, and other electron pair rearrangements arise naturally through the reaction progress simply in terms of the different ways of pairing up the electrons. A relationship between the topology and the nature of the bond breaking/forming processes along this rearrangement is reported. The different domains of structural stability of the ELF occurring along the intrinsic reaction path have been identified. The reaction mechanism consists of six steps separated by fold and cusp catastrophes. The transition structure is observed in the third step, d(C1-C8) = 2.342 Å, where all bonds have topological signature of single bonds (C-C). The "new" C1-C8 single bond is not formed in transition state and respective catastrophe of the ELF field (cusp) is localized in the last step, d(C1-C8) ≈ 1.97 Å, where the two monosynaptic nonbonding basins V(C1) and V(C8) are joined into single disynaptic bonding basin V(C1,C8). The V(C1,C8) basin corresponds to classical picture of the C1-C8 bond in the Lewis formula. In cycloocta-1,3,5-triene 6 the single C1-C8 bond is characterized by relatively small basin population 1.72e, which is much smaller than other single bonds with 2.03 and 2.26e.

4.
J Comput Chem ; 31(13): 2493-501, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20652991

RESUMO

Density functional theory was used to study the mechanism for the oxidation of methanol to formaldehyde. A vanadium oxide cluster O=V(OH)(3) has been utilized to represent the catalytic system under hydrated conditions, i.e., in the presence of V-OH hydroxyl groups. Two types of methoxy-intermediates have been considered: a penta-coordinate methoxy-intermediate (OH)(4)V(OCH(3)) and a tetrahedral methoxy-intermediate (OH)(2)VO(OCH(3))(H(2)O). The most plausible reaction pathway corresponds to the process involving first the formation of the tetrahedral methoxide, and a subsequent rate-limiting step where hydrogen is transferred from the methoxy groups toward the oxygen atom of the vanadyl V=O site. The reaction mechanism is a typical two-state reactivity process due to a change of the multiplicity (reactive singlet --> product triplet) along the reaction coordinate accompanied by a reduction of the vanadium center from V(V) (d(0)) to V(III) (d(2)). Minimum energy crossing points were localized and possible spin inversion processes are discussed by means of the intrinsic reaction coordinate approach to find the most favorable reaction pathways. The hydration effect is found to be mainly the destabilization of the methoxy intermediates. An alternative reaction pathway with a lower apparent barrier is presented.


Assuntos
Simulação por Computador , Formaldeído/síntese química , Metanol/química , Compostos de Vanádio/química , Catálise , Formaldeído/química , Oxirredução
5.
Microb Ecol ; 57(3): 550-61, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18797955

RESUMO

Dominant bacterial microbiota of the gut of juvenile farmed Atlantic salmon was investigated using a combination of molecular approaches. Bacterial community composition from the stomach, the pyloric caeca, and the intestine was assessed by extracting DNA directly from each gut compartment. Temporal temperature gradient gel electrophoresis (TTGE) analysis of 16S ribosomal DNA (rDNA) amplicons showed very similar bacterial compositions throughout the digestive tract. Band sequencing revealed a narrow diversity of species with a dominance of Pseudomonas in the three compartments. However, cloning revealed more diversity among the Pseudomonas sequences. To confirm these results, we analyzed the bacterial community by amplifying the variable 16S-23S rDNA intergenic spacer region (ITS). Similar ITS profiles were observed among gastrointestinal compartments of salmon, confirming the TTGE results. Moreover, the dominant ITS band at 650 bp, identified as Pseudomonas, was observed in the ITS profile from fish collected in two seasons (July 2003 and 2004). In contrast, aerobic culture analysis revealed Shewanella spp. as the most prevalent isolate. This discrepancy was resolved by evaluating 16S rDNA and ITS polymerase chain reaction amplification efficiency from both Shewanella and Pseudomonas isolates. Very similar efficiencies were observed in the two bacteria. Hence, this discrepancy may be explained by preferential cultivation of Shewanella spp. under the experimental conditions. Also, we included analyses of pelleted feed and the water influent to explore environmental influences on the bacterial composition of the gut microbiota. Overall, these results indicate a homogeneous composition of the bacterial community composition along the gastrointestinal tract of reared juvenile salmon. This community is mainly composed of Pseudomonas spp., which could be derived from water influent and may be selectively associated with salmon in this hatchery.


Assuntos
Trato Gastrointestinal/microbiologia , Pseudomonas/genética , Salmo salar/microbiologia , Shewanella/genética , Animais , Contagem de Colônia Microbiana , DNA Bacteriano/genética , DNA Intergênico/genética , Ecossistema , Polimorfismo de Fragmento de Restrição , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Shewanella/classificação , Shewanella/isolamento & purificação
6.
Transplant Proc ; 40(9): 2879-80, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19010134

RESUMO

Loss of donors as a consequence of a coroner's refusal to authorize is an unusual problem that prevents organs becoming available for transplantation. Of 1123 effective donors, 433 (38.5%) died of accidental death. In these latter, it was therefore necessary to request judicial authorization for donation during the coroner's examination. Organ extraction was not performed because of judicial refusal in 15 of these donors (3.46% of the total number of judicial extractions requested and 1.33% of the total number of donors). Despite the lack of differences in the cause of death profile in the four provinces, large differences were noted between the provinces, with most judicial refusals in Malaga (10 refusals; 6.6% of the total judicial refusals), followed by Granada with five refusals (2.9%), Seville with two refusals (1.7%), and zero in Almería. To minimize these judicial refusals, we propose joint action protocols between transplant coordinators, judges, and coroners for these donors to be examined in the hospital prior to extraction and in the operating room during extraction. Any external lesion of judicial interest can then be examined, photographed, and evaluated.


Assuntos
Doadores de Tecidos/legislação & jurisprudência , Acidentes por Quedas/estatística & dados numéricos , Acidentes/legislação & jurisprudência , Acidentes/estatística & dados numéricos , Acidentes de Trânsito/estatística & dados numéricos , Morte Encefálica/legislação & jurisprudência , Cadáver , Médicos Legistas/legislação & jurisprudência , Médicos Legistas/estatística & dados numéricos , Crime/estatística & dados numéricos , Afogamento/epidemiologia , Humanos , Espanha , Suicídio/estatística & dados numéricos , Doadores de Tecidos/estatística & dados numéricos
7.
Sci Total Environ ; 636: 727-736, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29727840

RESUMO

Woody encroachment has been an ongoing process in the subalpine belt of Mediterranean mountains, after land abandonment, the disappearance of the transhumant system and the decrease of the livestock number. The main objectives of this study were: (i) to identify land use/land cover (LULC) changes from 1956 to 2015, and (ii) to investigate the effects of LULC changes in physical and chemical soil properties and soil organic carbon (SOC) and nitrogen (N) stocks. It is hypothesized that woody encroachment in the subalpine belt may lead to significant changes in soil properties, and will generate an increase in the SOC stocks. A land use gradient was identified in the subalpine belt of the Central Spanish Pyrenees: (i) subalpine grasslands, (ii) shrublands, (iii) young forests, and (iv) old forests. Mineral soil samples were collected every 10 cm, down to 40 cm, at three points per each LULC and a total of 48 samples were analyzed. The results showed that (i) woody encroachment has occurred from 1956 to 2015 due to the expansion of coniferous forests and shrublands (at the expense of grasslands), (ii) land cover and soil depth had significant effects on soil properties (except for pH), being larger in the uppermost 0-10 cm depth, (iii) SOC and N contents and stocks were higher in the grassland sites, and (iv) the woody encroachment process initially produced a decrease in the SOC stocks (shrublands), but no differences were observed considering the complete soil profile between grasslands and young and old forests. Further studies, describing SOC stabilization and quantifying above-ground carbon (shrub and tree biomass) are required.

8.
Biol. Res ; 55: 9-9, 2022. ilus
Artigo em Inglês | LILACS | ID: biblio-1383913

RESUMO

BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans. This pathogen activates multiple regulatory mechanisms in response to stress, and cobalamin biosynthesis might have a potential role in bacterial protection. Low temperature is a strategy used in the food industry to control bacteria proliferation; however, L. monocytogenes can grow in cold temperatures and overcome different stress conditions. In this study we selected L. monocytogenes List2-2, a strain with high tolerance to the combination of low temperature +copper, to understand whether the cobalamin biosynthesis pathway is part of the tolerance mechanism to this stress condition. For this, we characterized the transcription level of three cobalamin biosynthesis related genes ( cbiP , cbiB, and cysG ) and the eutV gene, a transcriptional regulator encoding gene involved in ethanolamine metabolism, in L. monocytogenes strain List2-2 growing simultaneously under two environmental stressors: low temperature (8 °C) +copper (0.5 mM of CuSO4 ×5H2O). In addition, the gene cbiP , which encodes an essential cobyric acid synthase required in the cobalamin pathway, was deleted by homologous recombination to evaluate the impact of this gene in L. monocytogenes tolerance to a low temperature (8 °C) +different copper concentrations. RESULTS: By analyzing the KEGG pathway database, twenty-two genes were involved in the cobalamin biosynthesis pathway in L. monocytogenes List2-2. The expression of genes cbiP , cbiB, and cysG, and eutV increased 6 h after the exposure to low temperature +copper. The cobalamin cbiP mutant strain List2-2Δ cbiP showed less tolerance to low temperature +copper (3 mM) than the wild type L. monocytogenes List2-2. The addition of cyanocobalamin (5 nM) to the medium reverted the phenotype observed in List2-2Δ cbiP . CONCLUSION: These results indicate that cobalamin biosynthesis is necessary for L. monocytogenes growth under stress and that the cbiP gene may play a role in the survival and growth of L. monocytogenes List2-2 at low temperature +copper.


Assuntos
Humanos , Listeria monocytogenes/genética , Temperatura , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vitamina B 12/genética , Vitamina B 12/metabolismo , Temperatura Baixa , Cobre
9.
Clin Transl Oncol ; 18(10): 1011-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26758718

RESUMO

PURPOSE: In the present study we compared three different Stereotactic body radiation therapy (SBRT) treatment delivery techniques in terms of treatment time (TT) and their relation with intrafraction variation (IFV). Besides that, we analyzed if different clinical factors could have an influence on IFV. Finally, we appreciated the soundness of our margins. MATERIALS AND METHODS: Forty-five patients undergoing SBRT for stage I lung cancer or lung metastases up to 5 cm were included in the study. All underwent 4DCT scan to create an internal target volume (ITV) and a 5 mm margin was added to establish the planning target volume (PTV). Cone-beam CTs (CBCTs) were acquired before and after each treatment to quantify the IFV. Three different treatment delivery techniques were employed: fixed fields (FF), dynamically collimated arcs (AA) or a combination of both (FA). We studied if TT was different among these modalities of SBRT and whether TT and IFV were correlated. Clinical data related to patients and tumors were recorded as potential influential factors over the IFV. RESULTS: A total of 52 lesions and 147 fractions were analyzed. Mean IFV for x-, y- and z-axis were 1 ± 1.16 mm, 1.29 ± 1.38 mm and 1.17 ± 1.08 mm, respectively. Displacements were encompassed by the 5 mm margin in 96.1 % of fractions. TT was significantly longer in FF therapy (24.76 ± 5.4 min), when compared with AA (15.30 ± 3.68 min) or FA (17.79 ± 3.52 min) (p < 0.001). Unexpectedly, IFV did not change significantly between them (p = 0.471). Age (p = 0.003) and left vs. right location (p = 0.005) were related to 3D shift ≥2 mm. In the multivariate analysis only age showed a significant impact on the IFV (OR = 1.07, p = 0.007). CONCLUSIONS: The choice of AA, FF or FA does not impact on IFV although FF treatment takes significantly longer treatment time. Our immobilization device offers enough accuracy and the 5 mm margin may be considered acceptable as it accounts for more than 95 % of tumor shifts. Age is the only clinical factor that influenced IFV significantly in our analysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/cirurgia , Tomografia Computadorizada de Feixe Cônico/métodos , Tomografia Computadorizada Quadridimensional/métodos , Neoplasias Pulmonares/cirurgia , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Erros de Configuração em Radioterapia/prevenção & controle , Carga Tumoral
10.
Bol. micol. (Valparaiso En linea) ; 35(1): 17-25, jun. 2020. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: biblio-1437207

RESUMO

Tectona grandis L.f. es una especie forestal de madera dura que, a pesar de no ser nativa de América, su plasticidad de adaptación ha permitido que en Ecuador se establezcan plantaciones intensivas con fines de exportación. Una compleja enfermedad con características de marchitez vascular está matando miles de árboles de diferentes edades en el país. Se planteó conocer el agente fitopatógeno causante de la patogénesis y muerte de los árboles. Se aislaron los hongos Fusarium sp. y Ceratocystis fimbriata Ellis & Halst. desde árboles enfermos. A nivel de invernadero se plantearon los postulados de Koch, para el efecto 30 plantas de T. grandis de cuatro meses de edad por cada tratamiento, se inocularon con los microrganismos como se describe a continuación: T1= C. fimbriata, T2 = Fusarium sp., T3 = C. fimbriata + Fusarium sp., T4 = agar-agar (control). Se empleó un diseño completo al azar (DCA) y las plantas se evaluaron a los 45 días después de inoculadas. Los tratamientos C. fimbriata, y C. fimbriata + Fusarium sp., mostraron mayores volúmenes aparentes de necrosis, con 1.52 cm3 y 1.93 cm3, y plantas muertas por la infección durante el tiempo de evaluación, mientras que Fusarium sp. mostró baja o nula patogenicidad y comportamiento similar al control, con 0.27 cm3 y 0.16 cm3 respectivamente. Estos resultados sugieren que el agente causal de la enfermedad de marchitez vascular en T. grandis es C. fimbriata y sería el primer reporte del fitopatógeno atacando teca en Ecuador. (AU)


Tectona grandisL.f. it is a hardwood forest species, which despite not being native to America, its adaptive plasticity has allowed intensive plantations to be established for export purposes in Ecuador. A complex disease with characteristics of vascular wilt is killing thousands of trees of different ages in the country. It was proposed to know the phytopathogenic agent causing the pathogenesis and death of the trees. Fusarium sp. andCeratocystis fimbriata Ellis & Halst. were isolated from diseased trees. At the greenhouselevel, Koch's postulates were proposed, for the effect 30 four month old T. grandisplants for each treatment were inoculated with the microorganisms as described below: T1 = C. fimbriata, T2 = Fusariumsp ., T3 = C. fimbriata+ Fusariumsp., T4 = agar-agar (control). A complete randomized design (DCA) was used and the plants were evaluated 45 days after inoculation. The treatments C. fimbriata, and C. fimbriata+ Fusariumsp. showed higher apparent volumes of necrosis, with 1.52 cm3and 1.93 cm3, and plants killed by the infection during the evaluation time, while Fusariumsp. showed low or no pathogenicity and behavior similar to the control, with 0.27 cm3and 0.16 cm3respectively. These results suggest that the causative agent of vascular wilt disease in T. grandisis C. fimbriataand it would be the first report of phytopathogen attacking teak in Ecuador. (AU)


Assuntos
Árvores/microbiologia , Ceratocystis/patogenicidade , Florestas , Equador , Fusarium/patogenicidade
11.
Avian Dis ; 46(3): 686-90, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12243533

RESUMO

Ten gram-negative, pleomorphic, rod-shaped isolates from coryza-like, respiratory diseased laying and broiler chickens were identified as Ornithobacterium rhinotracheale. All O. rhinotracheale isolates showed typical biochemical and enzymatic characteristics. Also, all isolates showed hemagglutinating activity with glutaraldehyde-fixed erythrocytes. On the basis of this property, a rabbit-raised antiserum was produced for an isolate. All isolates were identified by antiserum by hemagglutination-inhibition tests. No cross-reactions were observed when O. rhinotracheale isolates were tested with Haemophilus paragallinarum antisera, and vice versa. Mild respiratory signs, including mild nasal discharge, slight rales, and sneezing, were observed in challenged chickens. At postmortem examination, multifocal pneumonia, airsacculitis, and foamy exudate in abdominal cavity were observed. Furthermore, because bacterial adherence is regarded as an essential step in the infection process, in vitro adherence of O. rhinotracheale isolates to chicken tracheal epithelial cells was tested. All isolates showed positive adherence. Obtained results indicate that O. rhinotracheale is a pathogenic agent present in the Mexican poultry.


Assuntos
Galinhas , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/veterinária , Doenças das Aves Domésticas/microbiologia , Infecções Respiratórias/veterinária , Animais , Aderência Bacteriana , Reações Cruzadas , Feminino , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/patogenicidade , Infecções por Bactérias Gram-Negativas/microbiologia , Testes de Inibição da Hemaglutinação/veterinária , Testes de Hemaglutinação/veterinária , Masculino , México , Infecções Respiratórias/microbiologia
12.
Sci Total Environ ; 242(1-3): 189-209, 1999 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-10635581

RESUMO

As a consequence of a mine tailing dam collapse on the 25th April 1998, more than 4000 ha of the Guadiamar riverflat and farmlands were flooded by 4 hm3 of sulphide slurry. A number of open wells (12 of the 47 analyzed) were also flooded and the water was contaminated. Before the spill, the groundwater in the aquifers was of calcium-carbonate and calcium-sulphate type, with moderate mineralisation and near neutral pH. With the exception of some of the wells close to the mine, this groundwater had a low concentration of the metals associated with the Aznalcóllar mine. After the flood the following metals had anomalous concentrations in well water: Zn, Mn, Pb, Co, Cd and Tl. Of these, Zn seems to be the best tracer of the contamination, owing to its high concentrations. During the 5 months following the spill, water from the unflooded wells did not show an increase in metal concentration. Apart from some exceptions in August, the metal concentration in the affected wells showed a progressive decrease reaching levels closer to those in the wells free from contamination. Nevertheless, in the following dry seasons the draw-down of the water level may lead to exposure and weathering of sulphides in the wells, which could cause an increase in pollution. Therefore, thorough cleaning of all highly contaminated wells is strongly recommended.


Assuntos
Acidentes de Trabalho , Mineração , Sulfetos , Poluentes Químicos da Água/análise , Desastres , Geografia , Espanha , Fatores de Tempo
15.
Rev Med Chil ; 128(10): 1093-100, 2000 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-11349507

RESUMO

BACKGROUND: Fetal drug addiction is a serious public health problem. In the United States 10 to 15% of children have been exposed "in utero" to cocaine. In a Chilean public health service, more than 200 offspring of cocaine free base abuser have been detected. AIM: To analyze the clinical and social features of 100 children exposed to cocaine free base during fetal development. PATIENTS AND METHODS: Clinical features of children born from cocaine free base consume mothers were described at birth. During subsequent follow up, growth and development, disease episodes, developmental alterations and social situation were recorded. Data was compared with other newborns from the same health service. RESULTS: Compared to their normal counterparts, exposed children has a lower birth weight, the frequency of premature babies was thrice higher, and small-for-gestational age children were four times more common. There was also a higher prevalence of cardiac malformations, seizures and apnea. Hospital admissions were more frequent, prolonged and required more complex facilities. During follow up, undernutrition and stunting were more prevalent. Psychomotor retardation was present in 67% of children and behavioral disturbances in 93%. Most of these children are governmental protection. CONCLUSIONS: Strategies to prevent drug abuse during pregnancy and its devastating medical and social consequences should be urgently developed (Rev Méd Chile 2000; 128: 1093-1100).


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Doenças Fetais/etiologia , Complicações na Gravidez , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Trabalho de Parto Prematuro/etiologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal
16.
Rev Med Chil ; 128(7): 767-71, 2000 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-11050838

RESUMO

BACKGROUND: Bacterial vaginosis (BV) is a common disease in reproductive-age women and is associated to important gynecologic and obstetric complications. AIM: To study the occurrence of BV in apparently healthy women attending family planning clinics, using Amsel and Nugent diagnostic criteria. MATERIAL AND METHODS: Two hundred thirty nine women consulting for symptoms associated to cervicovaginitis, were studied. A sample from the lateral walls of the vagina was obtained with a sterile swab for microscopic analysis, Gram stain and amine test. RESULTS: According to Amsel and Nugent criteria a 31.1% and 31.8% BV prevalence was observed. The sensitivity and specificity of Nugent criteria, compared with Amsel criteria were 83.3% and 92.1%, respectively. CONCLUSIONS: The high prevalence of BV found in this study suggests that this vaginal infection should be diagnosed with standardized methods. Nugent criteria are economic easy to perform and sensitive and we propose that they should be used in local health centers.


Assuntos
Esfregaço Vaginal/métodos , Vaginose Bacteriana/diagnóstico , Chile/epidemiologia , Feminino , Humanos , Valor Preditivo dos Testes , Prevalência , Sensibilidade e Especificidade , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/patologia
17.
Chem Res Toxicol ; 16(2): 208-15, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12588192

RESUMO

A series of C4-substituted 1,4-dihydropyridines (DHP) with either secondary or tertiary nitrogen in the dihydropyridine ring were synthesized. All of these compounds together with some commercial DHP derivatives were tested for potential scavenger effects toward alkyl, alkylperoxyl radicals, and ABTS radical cation in aqueous media at pH 7.4. Kinetic rate constants were assessed either by UV/vis spectroscopy or GC/MS techniques. Tested compounds reacted faster toward alkylperoxyl radicals and ABTS radical cation than alkyl ones. N-Ethyl-substituted DHPs showed the lowest reactivity. Kinetic results were compared with either trolox or nisoldipine. Using deuterium kinetic isotope effect studies, we have proved that the hydrogen of the 1-position of the DHP ring is involved in the proposed mechanism. This fact is mostly noticeable in the case of alkyl radicals. In all cases, the respective pyridine derivative was detected as the main product of the reaction.


Assuntos
Di-Hidropiridinas/química , Peróxidos/química , Ácidos Sulfônicos/química , Benzotiazóis , Cátions/química , Cromanos/química , Sequestradores de Radicais Livres/química , Radicais Livres/química , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Cinética , Nisoldipino/química , Espectrofotometria Ultravioleta , Vitamina E/análogos & derivados
18.
Rev Med Chil ; 128(6): 627-32, 2000 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-11016062

RESUMO

BACKGROUND: Pneumonia is the main cause of late infant mortality in Chile. Over 60% of these deaths occur at home. The lack of hospital beds and the inadequate outpatient management are contributing factors. AIM: To assess risk factors for home deaths due to pneumonia in Chilean children. PATIENTS AND METHODS: The clinical and environmental histories of 53 (39 male) children that died due to pneumonia in their homes were analyzed. The cause of death was confirmed by necropsy with histopathological studies in all cases. These cases were compared with 88 control children of similar age, gender, socioeconomic status and living in the same geographical area of Metropolitan Santiago. RESULTS: Fifty four percent of deceased children were of less than 3 months of age and only 3 cases and their controls were above 1 year old. Identified risk factors for death were malnutrition with an odds ratio of 30.6 (CI 3.9-64.8, p < 0.001), low birth weight with an odds ratio of 5 (CI 1.8-14.1, p < 0.001), previous admissions to hospitals with an odds ratio of 5.79 (CI 2-17.1, p < 0.001), congenital malformations (mainly cardiac) with an odds ratio of 8.4 (CI 2-39.9, p = 0.001) and a history of bronchial obstruction with an odds ratio of 5.68 (p < 0.001). Identified maternal risk factors were smoking with an odds ratio of 4.13 (CI 1.6-10.7 p < 0.001) and being a teenager with an odds ratio of 4.3 (CI 1.7-11, p < 0.001). Malnutrition, low birth weight, history of previous hospital admissions and having a teenager or smoker mother were considered as independent risk factors using a stepwise analysis. CONCLUSIONS: Chilean low income children have identifiable risk factors for death at their homes due to pneumonia, that can be preventively managed.


Assuntos
Pneumonia/mortalidade , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Habitação , Humanos , Lactente , Masculino , Fatores de Risco , Fatores Socioeconômicos
19.
Rev Med Chil ; 121(1): 98-105, 1993 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-8235175

RESUMO

Among children living in orphanages of the Metropolitan Region, the paternal alcohol ingestion patterns were investigated. According to abnormal parental alcohol ingestion, a sample of 291 children was studied, of whom 32% were living in simple protection homes for infants with normal intellectual coefficient and 52% in homes for mentally retarded boys. There was a higher frequency and intensity of abnormal alcohol ingestion among parents of infants living in homes for the mentally retarded. Among these, 29% of mothers were illiterate and 11% had incomplete primary school education compared to mothers of simple protection homes in whom the frequency of illiteracy was 10% and of incomplete primary education, 50%. Twenty percent of fathers of children living in homes for the mentally retarded were unemployed, 16% had occasional jobs and 11% had a stable work; these numbers were 11, 30 and 15% respectively for fathers of simple protection homes. Among infants living in homes for the mentally retarded, undernutrition was found in 44%, growth retardation in 51% and microcephaly in 34% compared to 33, 30 and 11% in children living in simple protection homes. Sixteen percent of the sample had fetal alcohol syndrome, 24% among those living in homes for the mentally retarded and 12% in simple protection homes. There was an inverse relationship between offspring intellectual coefficient and the number of drinking parents.


Assuntos
Consumo de Bebidas Alcoólicas , Alcoolismo , Criança Institucionalizada , Testes de Inteligência , Pais , Adolescente , Adulto , Criança , Pré-Escolar , Chile , Saúde da Família , Feminino , Transtornos do Espectro Alcoólico Fetal/etiologia , Humanos , Lactente , Deficiência Intelectual/etiologia , Masculino , Exame Neurológico , Estado Nutricional , Gravidez
20.
Clin Diagn Lab Immunol ; 9(5): 1067-71, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12204961

RESUMO

An increasing number of studies support a potential role for coccoid forms in Helicobacter pylori infection. Evidence for this was obtained through scanning microscopy, genetic analysis for virulence traits, examination of the presence and activity of key enzymes, and other methods. We studied the serum immunoglobulin G responses to coccoid H. pylori forms by enzyme-linked immunosorbent assay (ELISA) and immunoblotting and compared them with those of bacillary cells. Sera from a total of 295 infected individuals were studied; these included sera from 100 patients with duodenal ulcers, 98 patients with nonulcer dyspepsia, 11 patients with gastroduodenal cancer, and 86 asymptomatic individuals. Initially, we characterized and selected coccoid and bacillary antigenic preparations by one-dimensional (1-D) and 2-D gel electrophoresis and immunoblotting. Data showed that coccoid and bacillary preparations with comparable protein contents have similar patterns in 1-D and 2-D electrophoresis gels and antigenic recognition at blotting. These results revealed that coccoid and spiral antigens in ELISA can equally recognize specific antibodies to H. pylori in sera from infected individuals. The analysis of the spiral and coccoid preparations by Western blotting showed no major differences in antigen recognition. No specific bands or profiles associated with a single gastric condition were identified.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Adulto , Antígenos de Bactérias/análise , Western Blotting , Eletroforese em Gel Bidimensional , Ensaio de Imunoadsorção Enzimática , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Helicobacter pylori/ultraestrutura , Humanos , Imunoglobulina G/sangue , Virulência
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