RESUMO
In this work two systems based on a carbohydrate polymer were studied: inulin as model system and inulin-orange juice as complex system. Both system were stored at different water activity conditions and subsequently characterized. Water adsorption isotherms type II were fitted by the GAB model and the water monolayer content was determined for each system. From thermal analyzes it was found that at low water activities (aw) systems were fully amorphous. As aw increased, crystallinity was developed. This behavior was corroborated by X-ray diffraction. In the inulin-orange juice system, crystallization appears at lower water activity caused by the intensification of the chemical interaction of the low molecular weight species contained in orange juice. Glass transition temperature (Tg), determined by modulated differential scanning calorimeter, decreased with aw. As water is adsorbed, the physical appearance of samples changed which could be observed by optical microscopy and effectively related with the microstructure found by scanning electron microscopy.
Assuntos
Fenômenos Químicos , Citrus sinensis , Inulina/química , Inulina/isolamento & purificação , Termogravimetria/métodos , Água/análise , Água/química , Difração de Raios XRESUMO
The glass transition temperature of model food systems prepared with several glucose/fructose/sucrose mass fractions was studied using differential scanning calorimetry (DSC). A distance-based experimental design for mixtures of 3 components was used to establish the proportion of sugars of the model systems. Thus, 32 compositions including individual sugars and sugar mixtures, both binary and ternary were prepared and analyzed. Thermograms showing the complete process of heating-cooling-reheating were used to determine the precise glass transition temperature during cooling (T(g)(c)) or reheating (T(g)(H) in amorphous sugars. The Scheffe cubic model was applied to experimental results to determine the influence of sugar composition on the glass transition temperature (P < 0.05). The final model proved to be appropriate (R(2) > 0.97, CV < 9%, model significance <0.0001) to predict the T(g) values of any dry mixture of amorphous fructose, glucose, and sucrose.
Assuntos
Tecnologia de Alimentos , Frutose/análise , Glucose/análise , Sacarose/análise , Temperatura de Transição , Varredura Diferencial de Calorimetria/métodos , Cristalização , Manipulação de Alimentos , Frutas/química , Modelos Teóricos , Análise de Regressão , Termodinâmica , Difração de Raios X/métodosRESUMO
Using cDNA microarray analysis, we previously identified a set of differentially expressed genes in primary breast tumors based on the status of estrogen and progesterone receptors. In the present study, we performed an integrated computer-assisted and manual search of potential estrogen response element (ERE) binding sites in the promoter region of these genes to characterize their potential to be regulated by estrogen receptors (ER). Publicly available databases were used to annotate the position of these genes in the genome and to extract a 5’flanking region 2 kb upstream to 2 kb downstream of the transcription start site for transcription binding site analysis. The search for EREs and other binding sites was performed using several publicly available programs. Overall, approximately 40 percent of the genes analyzed were potentially able to be regulated by estrogen via ER. In addition, 17 percent of these genes are located very close to other genes organized in a head-to-head orientation with less than 1.0 kb between their transcript units, sharing a bidirectional promoter, and could be classified as bidirectional gene pairs. Using quantitative real-time PCR, we further investigated the effects of 17β-estradiol and antiestrogens on the expression of the bidirectional gene pairs in MCF-7 breast cancer cells. Our results showed that some of these gene pairs, such as TXNDC9/EIF5B, GALNS/TRAPPC2L, and SERINC1/PKIB, are modulated by 17β-estradiol via ER in MCF-7 breast cancer cells. Here, we also characterize the promoter region of potential ER-regulated genes and provide new information on the transcriptional regulation of bidirectional gene pairs.
Assuntos
Feminino , Humanos , Neoplasias da Mama/genética , Estradiol/genética , Regulação Neoplásica da Expressão Gênica/genética , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Elementos de Resposta/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Estradiol/metabolismo , Estradiol/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Elementos de Resposta/efeitos dos fármacos , Fatores de Transcrição/genética , Transcrição Gênica/genéticaRESUMO
Using cDNA microarray analysis, we previously identified a set of differentially expressed genes in primary breast tumors based on the status of estrogen and progesterone receptors. In the present study, we performed an integrated computer-assisted and manual search of potential estrogen response element (ERE) binding sites in the promoter region of these genes to characterize their potential to be regulated by estrogen receptors (ER). Publicly available databases were used to annotate the position of these genes in the genome and to extract a 5'flanking region 2 kb upstream to 2 kb downstream of the transcription start site for transcription binding site analysis. The search for EREs and other binding sites was performed using several publicly available programs. Overall, approximately 40% of the genes analyzed were potentially able to be regulated by estrogen via ER. In addition, 17% of these genes are located very close to other genes organized in a head-to-head orientation with less than 1.0 kb between their transcript units, sharing a bidirectional promoter, and could be classified as bidirectional gene pairs. Using quantitative real-time PCR, we further investigated the effects of 17ß-estradiol and antiestrogens on the expression of the bidirectional gene pairs in MCF-7 breast cancer cells. Our results showed that some of these gene pairs, such as TXNDC9/EIF5B, GALNS/TRAPPC2L, and SERINC1/PKIB, are modulated by 17ß-estradiol via ER in MCF-7 breast cancer cells. Here, we also characterize the promoter region of potential ER-regulated genes and provide new information on the transcriptional regulation of bidirectional gene pairs.
Assuntos
Neoplasias da Mama/genética , Estradiol/genética , Regulação Neoplásica da Expressão Gênica/genética , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Elementos de Resposta/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Estradiol/metabolismo , Estradiol/farmacologia , Feminino , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Elementos de Resposta/efeitos dos fármacos , Fatores de Transcrição/genética , Transcrição Gênica/genéticaRESUMO
We searched the genome of Mycosphaerella fijiensis for molecular markers that would allow population genetics analysis of this plant pathogen. M. fijiensis, the causal agent of banana leaf streak disease, also known as black Sigatoka, is the most devastating pathogen attacking bananas (Musa spp). Recently, the entire genome sequence of M. fijiensis became available. We screened this database for VNTR markers. Forty-two primer pairs were selected for validation, based on repeat type and length and the number of repeat units. Five VNTR markers showing multiple alleles were validated with a reference set of isolates from different parts of the world and a population from a banana plantation in Costa Rica. Polymorphism information content values varied from 0.6414 to 0.7544 for the reference set and from 0.0400 and 0.7373 for the population set. Eighty percent of the polymorphism information content values were above 0.60, indicating that the markers are highly informative. These markers allowed robust scoring of agarose gels and proved to be useful for variability and population genetics studies. In conclusion, the strategy we developed to identify and validate VNTR markers is an efficient means to incorporate markers that can be used for fungicide resistance management and to develop breeding strategies to control banana black leaf streak disease. This is the first report of VNTR-minisatellites from the M. fijiensis genome sequence.
Assuntos
Ascomicetos/genética , Marcadores Genéticos , Repetições Minissatélites , Musa/microbiologia , Doenças das Plantas/microbiologia , Sequência de Bases , Primers do DNA , Eletroforese em Gel de ÁgarRESUMO
Guanine-nucleotide exchange factors (GEFs) stimulate the intrinsic GDP/GTP exchange activity of Ras and promote the formation of active Ras-GTP, which in turn controls diverse signalling networks important for the regulation of cell proliferation, survival, differentiation, vesicular trafficking, and gene expression. RasGEF1b is a GEF, whose expression is induced in macrophages on stimulation with toll-like receptor (TLR) agonists. Here, we showed that in vitro RasGEF1b expression by macrophages is mostly induced by TLR3 (poly I:C) and TLR4 (lipopolysaccharyde) through the MyD88-independent pathway. In vivo infection with the protozoan parasites Trypanosoma cruzi and Plasmodium chabaudi induced RasGEF1b in an MyD88-, TRIF-, and IFN-gamma-dependent manner. Ectopically expressed RasGEF1b was found, mostly, in the heavy membrane fraction of HEK 293T, and by confocal microscopy, it was found to be located at early endosomes. Computational modelling of the RasGEF1b-Ras interaction revealed that RasGEF1b interacts with the binding domain site of Ras, a critical region for interacting with GEFs involved in the activation of Ras-Raf-MEK-ERK pathway. More important, RasGEF1b was found to be closely associated with Ras in live cells and to trigger Ras activity. Altogether, these results indicate that on TLR activation, RasGEF1b may trigger Ras-like proteins and regulate specific biological activities described for this subtype of GTPases.
Assuntos
Endossomos/metabolismo , Receptores Toll-Like/fisiologia , Fatores ras de Troca de Nucleotídeo Guanina/biossíntese , Animais , Células CHO , Cricetinae , Cricetulus , Endossomos/química , Feminino , Células HEK293 , Humanos , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/fisiologia , Lipopolissacarídeos/farmacologia , Macrófagos Peritoneais/química , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Toll-Like/metabolismo , Fatores ras de Troca de Nucleotídeo Guanina/metabolismo , Fatores ras de Troca de Nucleotídeo Guanina/fisiologiaRESUMO
There is scarce information concerning the epidemiology of Toxoplasma gondii infection in people of rural Mexico. Anti-T. gondii immunoglobulin (Ig)G and IgM antibodies were sought in 462 adult inhabitants from 3 rural communities of Durango, Mexico, using enzyme-linked immunoassays. In total, 110 (23.8%) of 463 persons had IgG anti-T. gondii antibodies. Ten (2.2%) of them also had IgM anti-T. gondii antibodies. Prevalences of T. gondii IgG antibodies in the 3 communities varied from 14.8 to 35.8%. The highest prevalence of infection was observed in participants older than 70 yr and in those with good housing conditions. Toxoplasma gondii infection was significantly associated with consumption of squirrel (adjusted odds ratio [OR] = 4.22; 95% confidence interval [CI] = 1.11-16.05) and turkey meat (adjusted OR = 4.58; 95% CI = 1.14-18.44). This is the first epidemiological study of T. gondii prevalence in rural Mexico.
Assuntos
Anticorpos Antiprotozoários/sangue , População Rural/estatística & dados numéricos , Toxoplasma/imunologia , Toxoplasmose/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos Transversais , Escolaridade , Feminino , Habitação/normas , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Carne/classificação , México/epidemiologia , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Distribuição por SexoRESUMO
Municipal waste is a potential source of infection for Toxoplasma gondii as it may contain contaminated meat with parasite tissue cysts and cat excrement with parasite oocysts. Therefore, we sought to determine the prevalence of T. gondii infection and associated characteristics in two populations exposed to municipal solid waste in Durango, Mexico. Ninety waste pickers and 83 waste workers of Durango City, Mexico were examined for T. gondii infection. They were tested for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. In addition, socio-demographic and behavioural characteristics from each participant were obtained. Nineteen (21.1%) of the 90 waste pickers and seven (8.4%) of the 83 waste workers were positive for anti-T. gondii IgG antibodies. The difference in prevalence among the groups was statistically significant (P =0.03). Waste pickers aged 31-50 years showed a significantly higher prevalence (40.9%) than waste workers of the same age group (2.9%, P < 0.001). Anti-T. gondii IgM antibodies were found in two (2.2%) of the waste pickers but in none of the waste workers. The seroprevalence of T. gondii was significantly higher in workers of the waste transfer station (25.0%) than in drivers or helpers of waste vehicles (2.5%) (P =0.03). Multivariate analysis showed that T. gondii infection was associated with consuming food found in the garbage [adjusted odds ratio (OR) = 4.4; 95% confidence interval (CI) 1.6-11.8] and with lack of education (adjusted OR = 3.2; 95% CI 1.1-8.8). From this study, we conclude: (i) waste pickers may represent a risk group for T. gondii infection; (ii) lack of education might be a contributing factor for T. gondii infection; (iii) the higher the exposure to garbage, the higher the seroprevalence of T. gondii infection; (iv) Eating food products from the garbage may represent an important route for T. gondii infection.
Assuntos
Anticorpos Antiprotozoários/sangue , Contaminação de Alimentos/análise , Higiene , Doenças Profissionais/epidemiologia , Toxoplasma/imunologia , Toxoplasmose/epidemiologia , Adulto , Animais , Gatos , Escolaridade , Feminino , Contaminação de Alimentos/prevenção & controle , Parasitologia de Alimentos , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Doenças Profissionais/prevenção & controle , Exposição Ocupacional , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose/prevenção & controle , ZoonosesRESUMO
Toxoplasma gondii and Neospora caninum are structurally similar parasites, with many hosts in common. The prevalence of antibodies to T. gondii and N. caninum was determined in sera from dogs from Durango City, Mexico. Using a modified agglutination test, antibodies to T. gondii were found in 52 (51.5%) of the 101 dogs with titers of 1:25 in 27, 1:50 in 11, 1:100 in 5, 1:200 in 4, 1:400 in 2, 1:800 in 2, and 1:3,200 or higher in 1. Antibodies to N. caninum were determined by the indirect immunofluorescent antibody test (IFAT) and the Neospora sp. agglutination test (NAT). Two of the 101 dogs had N. caninum antibodies; these dogs did not have T. gondii antibodies, supporting the specificity of the tests used. The N. caninum antibody titers of the 2 dogs were: 1:400 by IFAT and 1:200 by NAT in 1, and 1:25 by NAT and IFAT in the other. Results indicate that these 2 structurally similar protozoans are antigenically different.
Assuntos
Anticorpos Antiprotozoários/sangue , Coccidiose/veterinária , Doenças do Cão , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Coccidiose/epidemiologia , Coccidiose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Feminino , Masculino , México/epidemiologia , Prevalência , Toxoplasmose Animal/parasitologiaRESUMO
The prevalence of antibodies to Toxoplasma gondii was determined in sera from 105 domestic cats from Durango City, Mexico. Using a modified agglutination test, antibodies to this parasite were found in 21% of the 105 cats, with titers of 1:25 in 3 cats, 1:50 in 4 cats, 1:200 in 5 cats, 1:400 in 2 cats, 1:800 in 2 cats, 1:1,600 in 4 cats, and 1:3,200 or higher in 2 cats. Cats older than 1 yr had a significantly higher frequency of infection than that found in cats younger than 0.5 yr (41 vs. 13.2%, respectively; odds ratio = 4.55; 95% CI = 1.24-17.18; P = 0.01). Overall, the seroprevalence of T. gondii antibodies in cats in Durango, Mexico, is much lower compared with those reported in other countries.
Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Gato/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Doenças do Gato/imunologia , Doenças do Gato/parasitologia , Gatos , Feminino , Masculino , México/epidemiologia , Estudos Soroepidemiológicos , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/parasitologiaRESUMO
The thyroid function in full term newborn infants of 30 pregnant women given topical germicide providine-iodine (PVPI) during delivery was evaluated. For comparison 12 full term newborn infants of pregnant women using clorhexidine hydrochloride as germicide in selective cesarean section were designed as control. The two pregnant groups had similar median age (27.5 yr in PVPI group, range: 19-42 yr and 28.5 yr in control group, 19-40 yr) and gestational age (39 weeks, 38-42 weeks and 39.5 weeks, 38-42 weeks). Birth weight (3365 g, 2500-3860 g and 3265 g, 2850-4000 g) and the apgar score (9, 9-10 and 9, 8-10) of newborn were similar in both groups. Umbilical cord blood samples were taken after immediate clamping and serum total T3, total T4, free T4 and TSH concentrations were assayed by an immunofluorimetric method. T3, T4 and free T4 concentrations in the cord blood were not different in PVPI newborn infants (median values: 0.92 nmol/L, 135 nmol/L, and 15.9 pmol/L), in comparison to control newborns (0.97 mmol/L, 140.9 nmol/L and 17.3 pmol/L). In contrast, cord blood TSH concentration in newborn infants of PVPI pregnant women (median value: 6.47 mIU/L) was significantly higher (p < 0.01) than in control newborn infants (4.8 mIU/L). In PVPI exposed group 14 out of 30 newborn infants had TSH concentration above the upper value (6.7 mIU/L) observed in the control groups (X2 = 8.4, p < 0.01). These data suggest that fetal thyroid is susceptible even to acute iodine overload and support the recommendation that PVPI should be avoided during pregnancy.
Assuntos
Parto Obstétrico , Sangue Fetal/química , Recém-Nascido/sangue , Povidona-Iodo/farmacologia , Tireotropina/sangue , Adulto , Anti-Infecciosos Locais/farmacologia , Cesárea/efeitos adversos , Clorexidina/farmacologia , Saúde da Família , Feminino , Sangue Fetal/efeitos dos fármacos , Humanos , Mães , Gravidez , Glândula Tireoide/fisiologia , Tireotropina/efeitos dos fármacos , Tiroxina/sangue , Tiroxina/efeitos dos fármacos , Tri-Iodotironina/sangueRESUMO
The objective of the present study was to estimate the prevalence of herpes simplex virus type 2 (HSV 2) antibodies in child bearing women of 2 Brazilian populations with different socioeconomic status and to determine the risk of neonatal HSV exposure by means of maternal cultures at the onset of labor. The study was conducted at 2 hospitals: A, serving very low income patients and B, serving middle socioeconomic class. 173 participants from group A and 127 from B answered a questionnaire which showed that the patients had similar ages (27.7 and 26.8 years, respectively) but differed with regard to socioeconomic status, age at first intercourse (18.6 vs 20.6 years), number of sex partners (1.5 vs 1.2) and previous sexually transmitted diseases (15% vs. 1.5%). History of genital herpes was given by 11% of group A participants and by a similar number, 7%, of patients from group B. In addition, 200 serum samples from population A and 455 from B were tested by ELISA for anti HSV antibodies and 92% and 86%, respectively, were found to be positive. Sixty seropositive samples from group A and 90 from B were further analyzed by Western blot, which showed the presence of type 2 specific antibodies in 46% and 36%, respectively, suggesting an overall HSV 2 prevalence of 42% in group A and 31% in B. Cervical specimens were obtained for culture from 299 asymptomatic patients of population A and 313 of B. HSV was isolated from one specimen in each group, indicating a 0.3% incidence of asymptomatic viral excretion in both populations.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Herpes Genital/epidemiologia , Herpesvirus Humano 2/isolamento & purificação , Complicações Infecciosas na Gravidez/epidemiologia , Adulto , Brasil/epidemiologia , Feminino , Herpes Genital/sangue , Herpes Genital/transmissão , Humanos , Recém-Nascido , Gravidez , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Fatores SocioeconômicosRESUMO
The authors report six cases of myasthenia gravis during pregnancy. Three patients experienced increasing severity of their disease and one death occurred in the puerperium. The infants were born with no evidence of neonatal myasthenia. The patients should be closely monitored during labor and puerperium. This disease is characterized by unpredictable exacerbations, and the association of myasthenia gravis and pregnancy increases the risk for the patient.
Assuntos
Miastenia Gravis/terapia , Complicações na Gravidez/terapia , Brometo de Piridostigmina/uso terapêutico , Timectomia , Adulto , Peso ao Nascer , Feminino , Humanos , Recém-Nascido , Miastenia Gravis/cirurgia , Gravidez , Complicações na Gravidez/cirurgia , PrognósticoRESUMO
The authors present two cases of transabdominal cervicouterine cerclage using Benson and Durfee's technique. In both cases the surgery was successful and the patients gave birth at 37 and 40 weeks, respectively, to healthy newborns. The technique is recommended by the authors since technical details are observed.
Assuntos
Colo do Útero/cirurgia , Técnicas de Sutura , Incompetência do Colo do Útero/cirurgia , Aborto Habitual/prevenção & controle , Adulto , Feminino , Humanos , GravidezRESUMO
The reaction to immersion in cold water (22 degrees C) was studied in ten healthy male volunteers successively receiving balanced (C), hypercarbohydrate (HC), hyperprotein (HP), and hyperlipid (HL) normocaloric diets with a three week equilibration period on each diet. Oxygen consumption (ml min-1 m-2) increased from 149 to 224 during C, from 160 to 196 during HL, from 154 to 178 during HP, and from 166 to 187 during HL. Only the first two differences were significant. Pulmonary ventilation (ml min-1 m-2) increased from 4.08 to 6.24 during C, from 4.01 to 5.48 during HC, from 3.41 to 3.83 during HP, and from 3.77 to 5.48 during HL. The difference was statistically significant only for C. Heart rate (beats/min) decreased from 73 to 64 during C, from 74 to 61 during HC, from 73 to 60 during HP and from 72 to 64 during HL. The differences were statistically significant for all diets except HL. Oral temperature decreased in all groups (range 0.4 to 1.6 degrees C). Respiratory rate changes were not statistically significant. The calorigenic reaction to cold water immersion was demonstrable for all groups but more efficient in subjects receiving either balanced or HC diets, suggesting that HP and HL diets reduce cold adaptation.
Assuntos
Temperatura Corporal , Temperatura Baixa , Dieta , Frequência Cardíaca , Imersão , Consumo de Oxigênio , Adulto , Ingestão de Energia , Humanos , Masculino , Pessoa de Meia-Idade , RespiraçãoAssuntos
Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Temperatura Corporal , Temperatura Baixa , Ingestão de Energia , Frequência Cardíaca , Imersão , Consumo de OxigênioAssuntos
Gravidez , Adulto , Humanos , Feminino , Coração Fetal , Frequência Cardíaca , Isoantígenos , Monitorização FetalRESUMO
Os autores utilizaram prostaglandina F2 alfa na inducao do parto em 19 pacientes com idade gestacional superior a 35 semanas. Em doses adequadas, nao houve complicacoes clinicas de grande importancia, a nao ser em um caso onde acidentalmente ocorreu superdosagem.Em apenas uma vez ocorreu falta da inducao. Os recem-nascidos tiveram indice de Apgar satisfatorio e apresentaram ocorrencia nao usual de ictericia neonatal, que merece melhor investigacao
Assuntos
Adolescente , Adulto , Humanos , Feminino , Trabalho de Parto Induzido , Prostaglandinas FRESUMO
Estudaram-se 20 casos de obitos maternos ocorridos no Hospital do Servidor Publico Estadual Francisco Morato de Oliveira, de Sao Paulo, no preiodo de dez anos. O coeficiente de mortalidade materna foi de 7,20/10 mil nascidos vivos, numero esse bastante favoravel quando se compara aos de varios autores nacionais e estrangeiros. A maioria dos obitos deveu-se a causas obstetricas diretas (10) seguidas por causas nao obstetricas (8) e pelas obstetricas indiretas (2). Das obstetricas diretas, o maior contingente foi consequencia de infeccoes (5), seguido das hemorragias (3) e a toxemia (2)