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1.
J Appl Microbiol ; 128(2): 387-400, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31573730

RESUMO

AIMS: To study the individual and combined contribution of catechin, protocatechuic and vanillic acids to inhibit the adhesion of uropathogenic Escherichia coli (UPEC) on the surface of silicone catheters. METHODS AND RESULTS: The adhesion of UPEC to silicone catheters during the exposure to nonlethal concentrations of phenolic compounds was measured, as well as changes in motility, presence of fimbriae, extra-cellular polymeric substances, surface charge, hydrophobicity and membrane fluidity. The phenolic combination reduced 26-51% of motility, 1 log CFU per cm2 of adhered bacteria and 20-40% the carbohydrate and protein content in the biofilm matrix. Curli fimbriae, surface charge and cell hydrophobicity were affected to a greater extent by the phenolic combination. In the mixture, vanillic acid was the most effective for reducing bacterial adhesion, extra-polymeric substance production, motility, curli fimbriae and biofilm structure. Notwithstanding, protocatechuic acid caused major changes in the bacterial cell surface properties, whereas catechin affected the cell membrane functionality. CONCLUSION: Catechin, protocatechuic and vanillic acids have different bacterial cell targets, explaining the synergistic effect of their combination against uropathogenic E. coli. SIGNIFICANCE AND IMPACT OF STUDY: This study shows the contribution of catechin, protocatechuic and vanillic acids in producing a synergistic mixture against the adhesion of uropathogenic E. coli on silicone catheters. The action of catechin, vanillic and protocatechuic acids included specific contributions of each compound against the E. coli membrane's integrity, motility, surface properties and production of extracellular polymeric substances. Therefore, the studied mixture of phenolic compounds could be used as an antibiotic alternative to reduce urinary tract infections associated with silicone catheters.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Catequina/farmacologia , Hidroxibenzoatos/farmacologia , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Ácido Vanílico/farmacologia , Catéteres/microbiologia , Sinergismo Farmacológico , Infecções por Escherichia coli/microbiologia , Fímbrias Bacterianas/efeitos dos fármacos , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Humanos , Fenóis/farmacologia , Silicones/análise , Escherichia coli Uropatogênica/crescimento & desenvolvimento , Escherichia coli Uropatogênica/fisiologia
2.
Cleft Palate Craniofac J ; 53(1): 30-7, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-25844562

RESUMO

OBJECTIVE: To develop a yardstick of reference photographs for nasolabial appearance assessments of 5- to 7-year-old patients with complete unilateral cleft lip and palate (CUCLP). DESIGN: Blind retrospective analysis of clinical records and comparison to historical controls. PATIENTS: Subjects were two groups of 6- to 12-year-olds (n = 124 and n = 135) and one group of 5- to 7-year-olds (n = 149) with nonsyndromic CUCLP from three previous Americleft studies, including cohorts from seven different cleft/craniofacial centers. INTERVENTIONS: All patients received the infant management protocols of their respective centers. Eleven trained and calibrated judges (five participated in all three studies) did blind ratings of nasolabial appearance using the Asher-McDade method. MAIN OUTCOME MEASURES: Patients receiving the most consistent ratings between judges, selected first from the groups of 6- to 12-year-olds, were used to create a pilot yardstick for eventual use in the third study of 5- to 7-year-olds. For each of the Asher-McDade categories, 8 of the 5- to 7-year-old patients receiving the most consistent scores between raters were ranked by 10 judges for a final elimination to leave three per category. RESULTS: Using this method of successive changes in rating methods, a new reference yardstick for nasolabial appearance rating was established and linked to the original Asher-McDade method as well as the single examples in a previously published yardstick for patients with CUCLP. Pilot testing using the yardstick improved reliabilities. CONCLUSIONS: Use of an expanded nasolabial yardstick of reference photographs representative of the range of possibilities of each of the five Asher-McDade categories is now available to see if reliability of these ratings can be improved.


Assuntos
Fenda Labial/patologia , Fissura Palatina/patologia , Estética , Fotografação , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estados Unidos
3.
Cleft Palate Craniofac J ; 53(5): 508-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26218534

RESUMO

OBJECTIVE: To compare length of follow-up and cleft site dental management on bone graft ratings from two centers. DESIGN: Blind retrospective analysis of cleft site radiographs and chart reviews for determination of cleft-site lateral incisor management. PATIENTS: A total of 78 consecutively grafted patients with complete clefts from two major cleft/craniofacial centers (43 from Center 1 and 35 from Center 2). INTERVENTIONS: Secondary iliac crest alveolar bone grafting, at a mean age of 9 years 9 months (Center 1: 9 years 7 months; Center 2: 10 years 0 month). MAIN OUTCOME MEASURES: The Americleft Standardized Way to Assess Grafts scale from 0 (failed graft) to 6 (ideal) was used to rate graft outcome at two time points (T1, T2). Average T1 was 11 years 1 month of age, 1 year 3 months postgraft. Average T2 was 17 years 11 months of age, 8 years 0 months postgraft. Six trained and calibrated raters scored each radiograph twice. Reliability was calculated at T1 and T2 using weighted kappa. A paired Wilcoxon signed rank test (P < .05) tested T1 and T2 differences for each center. A Kruskal-Wallis test was used to determine the significance of differences between centers at T1 and T2. Correlation tested whether T1 ratings predicted T2. Linear regression determined possible factors that might contribute to graft rating changes over time. RESULTS: Reliability was good at T1 and T2 (interrater = .713 and .701, respectively; intrarater = .790 and .805, respectively). Center 1 scores were significantly better than those from Center 2 at both T1 (5.21 versus 3.29) and T2 (5.18 versus 3.44). There was no statistical difference between T1 and T2 scores for either center; although, there was a greater chance of bone graft score improving with completion of canine eruption and substitution for missing lateral incisors. CONCLUSIONS: Short-term ratings of graft outcomes identified significant differences between centers that persisted over time. Dental cleft-site management influenced final graft outcome.


Assuntos
Enxerto de Osso Alveolar , Transplante Ósseo , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Adolescente , Processo Alveolar , Criança , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento
4.
J Anim Physiol Anim Nutr (Berl) ; 99(1): 100-106, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24846662

RESUMO

A key concern with the flooding dose technique for measuring protein synthesis is that a large dose of amino acid (AA) can potentially change the animals' hormonal and nutritional status, which in turn can influence protein synthesis. Among stable isotope tracers, 1-[(13)C]-valine is the preferred AA for measuring protein synthesis in gut tissue and mucins. A study was conducted to determine the impact of a flooding dose of valine on the metabolic status of pigs. Six barrows [16.5 kg body weight (BW)] were randomly assigned to intravenous infusions of either 150 mM valine (1.5 mmol/kg BW) or physiological saline, following a crossover design. Blood samples were taken 10 min prior to infusion, at the end of infusion, at 10-min intervals for 60 min post-infusion, and at 90 and 120 min post-infusion. Plasma concentrations of insulin, glucose, AA, urea nitrogen and packed cell volume (PCV) were measured. Infusion of valine increased plasma valine concentrations (4129 vs. 582 µM; P < 0.05) but had no influence on PCV (26.4% vs. 27.2%) and plasma concentrations of glucose (6.0 vs. 5.8 mM) and insulin (8.2 vs. 8.5 µU/ml; P > 0.10). Plasma urea nitrogen concentration was reduced with valine infusion (8.5 vs. 7.8 mg/dl; P < 0.05). A flooding dose of valine had no impact on plasma concentrations of AA, and specifically branched-chain AA such as leucine (240 vs. 231 µM) and isoleucine (310 vs. 331 µM; P > 0.10). There was, however, a slight increase in the plasma concentrations of threonine (224 vs. 263 µM; P < 0.05) and a tendency towards reduced glycine (1387 vs. 1313 µM; P < 0.10). The results indicate that a flooding dose of valine does not cause a substantial change in the metabolic status of growing pigs and is therefore suitable for measuring protein synthesis rates.


Assuntos
Suínos/metabolismo , Valina/farmacologia , Aminoácidos/sangue , Aminoácidos/metabolismo , Animais , Biomarcadores , Estudos Cross-Over , Relação Dose-Resposta a Droga , Metabolismo Energético , Hematócrito , Masculino , Suínos/crescimento & desenvolvimento , Valina/administração & dosagem
5.
Orthod Craniofac Res ; 17(4): 216-25, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24846148

RESUMO

OBJECTIVES: 1) To determine the concordance among surgeons on subjective assessments of nasolabial esthetics in children with repaired cleft lip; and 2) to evaluate longitudinal changes in nasolabial esthetics in relation to cleft lip revision surgery. SETTING AND SAMPLE POPULATION: School of Dentistry at University of North Carolina, Chapel Hill. Children with repaired unilateral cleft lip: 32 had lip revision surgery and 27 did not have surgery. MATERIALS AND METHODS: Retrospective observational study from a non-randomized clinical trial. Ratings of nasolabial esthetics performed by six surgeons using the Asher-McDade scale at baseline and 12-month follow-up. RESULTS: Concordance among surgeons ranged from poor to acceptable. Nasolabial ratings at follow-up were better in the Revision group than in the Non-Revision group, although differences were small. The most prevalent change in the Revision Group was improvement in one or more units on the scale, while 'no change' was most prevalent in the Non-Revision group. Participants in the Revision group were more likely to receive a 'no' in relation to the need for lip or nose revision at the follow-up visit. CONCLUSION: There were mild esthetic improvements observed in relation to lip revision surgery, which should be interpreted with caution given the subjectivity of the rating method used.


Assuntos
Fenda Labial/cirurgia , Estética , Lábio/cirurgia , Nariz/anatomia & histologia , Adolescente , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Criança , Fissura Palatina/cirurgia , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Lábio/anatomia & histologia , Estudos Longitudinais , Masculino , Ensaios Clínicos Controlados não Aleatórios como Assunto , Fotografação/métodos , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
6.
Biomed Pharmacother ; 174: 116555, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593708

RESUMO

Calprotectin (CP), a heterodimer of S100A8 and S100A9, is expressed by neutrophils and a number of innate immune cells and is used widely as a marker of inflammation, particularly intestinal inflammation. CP is a ligand for toll-like receptor 4 (TLR4) and the receptor for advanced glycation end products (RAGE). In addition, CP can act as a microbial modulatory agent via a mechanism termed nutritional immunity, depending on metal binding, most notably Zn2+. The effects on the intestinal epithelium are largely unknown. In this study we aimed to characterize the effect of calprotectin on mouse jejunal organoids as a model epithelium, focusing on Zn2+ metabolism and cell proliferation. CP addition upregulated the expression of the Zn2+ absorptive transporter Slc39a4 and of methallothionein Mt1 in a Zn2+-sensitive manner, while downregulating the expression of the Zn2+ exporter Slc30a2 and of methallothionein 2 (Mt2). These effects were greatly attenuated with a CP variant lacking the metal binding capacity. Globally, these observations indicate adaptation to low Zn2+ levels. CP had antiproliferative effects and reduced the expression of proliferative and stemness genes in jejunal organoids, effects that were largely independent of Zn2+ chelation. In addition, CP induced apoptosis modestly and modulated antimicrobial gene expression. CP had no effect on epithelial differentiation. Overall, CP exerts modulatory effects in murine jejunal organoids that are in part related to Zn2+ sequestration and partially reproduced in vivo, supporting the validity of mouse jejunal organoids as a model for mouse epithelium.


Assuntos
Proliferação de Células , Mucosa Intestinal , Jejuno , Complexo Antígeno L1 Leucocitário , Organoides , Zinco , Animais , Zinco/metabolismo , Organoides/metabolismo , Organoides/efeitos dos fármacos , Complexo Antígeno L1 Leucocitário/metabolismo , Jejuno/metabolismo , Jejuno/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Camundongos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Metalotioneína/metabolismo , Metalotioneína/genética , Inflamação/metabolismo , Inflamação/patologia , Biomarcadores/metabolismo , Masculino
7.
Genet Mol Res ; 12(3): 2755-63, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23979900

RESUMO

We investigated associations between vitamin D receptor (VDR) gene polymorphisms, FokI T>C (rs2228570), BsmI G>A (rs1544410), ApaI G>T (rs7975232), and TaqI T>C (rs731236), with bone mineral density (BMD) in postmenopausal Mexican-Mestizo women. Three hundred and twenty postmenopausal women participated, who were classified according to World Health Organization criteria as non-osteoporotic (Non-OP; N = 88), osteopenic (Opn; N = 144), and osteoporotic (OP; N = 88). BMD measurements at the lumbar (L1-L4) spine and at the left and right femoral neck were obtained by dual-energy X-ray absorptiometry. Single nucleotide polymorphisms (SNPs) were genotyped using real-time polymerase chain reaction and TaqMan probes. Genotype and allelic frequencies of the 4 VDR SNPs were similar among the 3 groups. Polymorphic allele frequencies were as follows: FokI (C) 0.53, 0.49, 0.56; BsmI (A) 0.26, 0.22, 0.23; ApaI (T) 0.43, 0.39, 0.44; TaqI (C) 0.27, 0.22, 0.23 for the Non-OP, Opn, and OP groups, respectively. Although no associations were found between the SNPs and BMD, based on the putative function of the FokI SNP, we constructed, for the first time, the haplotype with the 4 VDR SNPs, and found that the CGGT haplotype differed between the Non- OP and OP groups (21.8 vs 31.8%, P < 0.05). The risk analysis for this haplotype was nearly significant under the dominant model (OR = 1.783, 95%CI = 0.98-3.25, P = 0.058). This result suggests a possible susceptibility effect of the C allele of the FokI SNP for the development of osteoporosis in postmenopausal Mexican-Mestizo women.


Assuntos
Densidade Óssea/genética , Osteoporose/genética , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/genética , Idoso , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Haplótipos , Humanos , Indígenas Norte-Americanos/genética , México , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Radiografia
8.
Hernia ; 25(5): 1183-1187, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33983568

RESUMO

INTRODUCTION: The EHS clinical guidelines recommend the use of mesh to repair symptomatic primary inguinal hernias (PIH) in adult males but, in spite of this, it begs the question as to why there is still place for tissue techniques. Lack of stratification of patients according to risk of recurrence in RCTs might be a cause of results disparity, since medial and mixed are hernias with higher risk of recurrence (HRRH), whereas lateral hernias present a lower risk (LRRH). OBJECTIVE: To determine whether the lack of stratification may lead to questionable conclusions regarding the protective effect of mesh techniques and to identify other methodological flaws. METHODS: In the RCTs included in the clinical guidelines that addressed recurrences of PIH after mesh and non-mesh techniques, we assessed the type of hernias classification used, the number needed to treat in LRRH and HRRH and the statistical power. RESULTS: Most of trials were underpowered; five studies classified the hernia types; in the three studies that compared the recurrence rates of LRRH and HRRH the effect of mesh techniques was small; only two trials record data needed to calculate the NNT in LRRH (46 y 84 patients, respectively). CONCLUSION: The idea that mesh techniques reduce the recurrence rate in all PIHs is not supported by high level of evidence. The NNT for pure lateral hernias was very high and should be interpreted taking into account chronic pain rates and costs.


Assuntos
Dor Crônica , Hérnia Inguinal , Adulto , Hérnia Inguinal/cirurgia , Herniorrafia , Humanos , Masculino , Recidiva , Telas Cirúrgicas
9.
Pediatr Obes ; 14(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30225981

RESUMO

BACKGROUND: Weight loss interventions can have positive 'ripple' effects on untreated partners in the home, but ripple effects on infants are unknown. OBJECTIVE: To examine whether a 12-month internet-based weight loss intervention for postpartum mothers had a positive ripple effect on participants' infants. METHODS: A 12-month cluster randomized, assessor-blind, clinical trial enrolling 371 postpartum women at 12 Women, Infants, Children clinics in CA. Clinics were randomized to standard Women, Infants, Children or an internet-based weight loss intervention for mothers. RESULTS: A total of 333 of the 371 (89.8%) mothers assented for infant participation. Infants were 5.3 ± 3.2 months; 75.9% were Hispanic and 64% were breastfeeding. Infant retention was 272/333 (82.7%) at 6 months post enrollment and 251/333 (75.3%) at 12 months post enrollment. In intent-to-treat analysis, a significant interaction between group and time was observed (p = 0.008) with the offspring of intervention mothers exhibiting lower zBMI change from study entry through 6 months (0.23 [CI, 0.03, 0.44] vs. 0.65 [0.50, 0.79] zBMI change, respectively; p = 0.001) but was not significant through 12 months (p = 0.16). Regardless of group, maternal reports at the final assessment indicated that infants (aged =17.2 ± 3.4 months) consumed sweetened beverages (0.93 ± 1.5/week), juice (2.0 ± 1.4/day), 'junk food' (7.8 ± 5.4/week) and fast food (2/month), and 46.7% of the infants had a TV in their bedroom. CONCLUSIONS: An internet-based weight loss program for low-income, postpartum mothers had a positive 'ripple' effect on the zBMI of infants in the home during the first 6 months of treatment.


Assuntos
Índice de Massa Corporal , Desenvolvimento Infantil/fisiologia , Telemedicina/métodos , Programas de Redução de Peso/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Lactente , Comportamento do Lactente/psicologia , Internet , Masculino , Mães , Período Pós-Parto/fisiologia , Pobreza , Adulto Jovem
10.
J Cell Commun Signal ; 13(4): 531-537, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30903602

RESUMO

The main goal of this study was to evaluate the inhibition of Pseudomonas aeruginosa virulence factors and Quorum Sensing during exposure to carvacrol. P. aeruginosa (ATCC 10154) was exposed to carvacrol determining changes in biofilm development, motility, acyl-homoserine lactones (AHL) synthesis and relative expression of lasI/lasR. Docking analysis was used to determinate interactions between carvacrol with LasI and LasR proteins. P. aeruginosa produced 60% lower AHLs when exposed to carvacrol (1.9 mM) compared to control, without affecting cellular viability, indicating a reduction on the LasI synthase activity. AHL-C12, C6, and C4 were detected and related to biofilm development, motility, and pyocyanin production, respectively. The presence of carvacrol reduced the expression of lasR, without affecting lasI gen. Moreover, computational docking showed interactions of carvacrol with amino acids in the active site pocket of LasI (-5.6 kcal mol-1) and within the binding pocket of LasR (-6.7 kcal mol-1) of P. aeruginosa. These results demonstrated that virulence of P. aeruginosa was reduced by carvacrol, by inhibiting LasI activity with the concomitant reduction on the expression of lasR, biofilm and swarming motility. This study provides relevant information about the effect of carvacrol against quorum sensing to inhibit virulence factors of P. aeruginosa at enzymatic and gene levels. These findings can contribute to the development of natural anti-QS products, which can affect pathogenesis.

11.
Appl Environ Microbiol ; 74(10): 2997-3001, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18359829

RESUMO

Batch solar disinfection (SODIS) inactivation kinetics are reported for suspensions in water of Campylobacter jejuni, Yersinia enterocolitica, enteropathogenic Escherichia coli, Staphylococcus epidermidis, and endospores of Bacillus subtilis, exposed to strong natural sunlight in Spain and Bolivia. The exposure time required for complete inactivation (at least 4-log-unit reduction and below the limit of detection, 17 CFU/ml) under conditions of strong natural sunlight (maximum global irradiance, approximately 1,050 W m(-2) +/- 10 W m(-2)) was as follows: C. jejuni, 20 min; S. epidermidis, 45 min; enteropathogenic E. coli, 90 min; Y. enterocolitica, 150 min. Following incomplete inactivation of B. subtilis endospores after the first day, reexposure of these samples on the following day found that 4% (standard error, 3%) of the endospores remained viable after a cumulative exposure time of 16 h of strong natural sunlight. SODIS is shown to be effective against the vegetative cells of a number of emerging waterborne pathogens; however, bacterial species which are spore forming may survive this intervention process.


Assuntos
Desinfecção/métodos , Bactérias Gram-Negativas/efeitos da radiação , Bactérias Gram-Positivas/efeitos da radiação , Luz Solar , Microbiologia da Água , Bolívia , Contagem de Colônia Microbiana , Viabilidade Microbiana , Espanha , Esporos Bacterianos/efeitos da radiação , Fatores de Tempo
12.
J Dev Orig Health Dis ; 9(4): 467-472, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29706142

RESUMO

Animal and cross-sectional epidemiological studies suggest that prenatal lead exposure is related to delayed menarche, but this has not been confirmed in longitudinal studies. We analyzed this association among 200 girls from Mexico City who were followed since the first trimester of gestation. Maternal blood lead levels were analyzed once during each trimester of pregnancy, and daughters were asked about their first menstrual cycle at a visit between the ages of 9.8 and 18.1 years. We estimated hazard ratios (HRs) and 95% confidence intervals (CI) for probability of menarche over the follow-up period using interval-censored Cox models, comparing those with prenatal blood lead level ⩾5 µg/dl to those with prenatal blood lead <5 µg/dl. We also estimated HRs and 95% CI with conventional Cox regression models, which utilized the self-reported age at menarche. In adjusted analyses, we accounted for maternal age, maternal parity, maternal education, and prenatal calcium treatment status. Across trimesters, 36-47% of mothers had blood lead levels ⩾5 µg/dl. Using interval-censored models, we found that during the second trimester only, girls with ⩾5 µg/dl prenatal blood lead had a later age at menarche compared with girls with prenatal blood lead levels <5 µg/dl (confounder-adjusted HR=0.59, 95% CI 0.28-0.90; P=0.05). Associations were in a similar direction, although not statistically significant, in the conventional Cox regression models, potentially indicating measurement error in the self-recalled age at menarche. In summary, higher prenatal lead exposure during the second trimester could be related to later onset of sexual maturation.


Assuntos
Chumbo/efeitos adversos , Exposição Materna/efeitos adversos , Menarca/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/etiologia , Maturidade Sexual/efeitos dos fármacos , Adolescente , Adulto , Fatores Etários , Criança , Feminino , Humanos , Estudos Longitudinais , México , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia
13.
J Clin Invest ; 56(6): 1386-95, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-172529

RESUMO

Experiments were carried out in normal dogs to characterize the mechanisms by which sodium bicarbonate administration results in increased excretion of phosphate. Infusion of sodium bicarbonate alone increased fractional phosphate excretion from 0.8 to 29.3%. During bicarbonate administration, ionized calcium fell and mean parathyroid hormone values increased from 59.6 to 230.4 muleq/ml. In the same group of dogs, administration of sodium bicarbonate plus calcium prevented the fall in ionized calcium, and parathyroid hormone levels remained unchanged. In these dogs fractional phosphate excretion increased from 2.4 to only 4.9%. Similar results were obtained in thyroparathyroidectomized dogs receiving sodium bicarbonate. In these dogs fractional excretion of phosphate increased from 0.6 to 4.5%. Under all three experimental conditions no differences were observed in sodium or bicarbonate excretion or in urinary or plasma pH. Administration of hydrochloric acid, after phosphaturia had been induced by the infusion of bicarbonate, resulted in a decrease in plasma bicarbonate and an acid urine; however, the phosphaturia persisted even in the presence of an acid urine pH. In five thyroparathyroidectomized dogs infused with parathyroid hormone throughout, administration of identical amounts of sodium as either NaCl or NaHCO3 resulted in a similar degree of phosphaturia despite significant differences in urine pH. These experiments suggest that a rise in parathyroid hormone levels, resulting from a fall in ionized calcium, is the major mechanism by which bicarbonate administration produces phosphaturia. An increased natriuresis per nephron, as a consequence of extracellular fluid volume expansion, contributes to the phosphaturia. On the other hand, alkalinization of the urine does not play a significant role in the phosphaturia seen after bicarbonate administration.


Assuntos
Bicarbonatos/farmacologia , Cálcio/sangue , Hormônio Paratireóideo/sangue , Fosfatos/urina , Animais , Cálcio/farmacologia , Cálcio/urina , AMP Cíclico/urina , Cães , Feminino , Ácido Clorídrico/farmacologia , Túbulos Renais/metabolismo , Natriurese/efeitos dos fármacos , Sódio/farmacologia , Cloreto de Sódio/farmacologia , Tireoidectomia
14.
J Clin Invest ; 58(5): 1273-9, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-186487

RESUMO

Available evidence indicates that serum magnesium (Mg++) levels influence the secretion rate of parathyroid hormone (PTH). Whether serum Mg++ concentrations also modify the action of PTH on its target organs has not been definitively established. The present experiments were designed to study this possibility. The effect of infusing PTH on the urinary excretion of cyclic AMP (cAMP) and PO4= was examined in five normal dogs at two different levels of serum Mg++. At normal serum Mg++ concentrations (1.89 +/- 0.14 mg/100 ml), PTH infusion increased cAMP excretion from 1.76 +/- 0.27 to 4.87 +/- 1.00 nmol/min and fractional PO4= excretion (FEPO4) from 1.58 +/- 0.36% to 23.1 +/- 2.17%. When an identical amount of PTH was given to the same dogs at a serum Mg++ of 4.36 +/- 0.20 mg/100 ml, FEPO4 increased to only 6.02+/-1.89% and cAMP from 1.31 +/- 0.23 to 1.89 +/- 0.39 nmol/min. Identical results were obtained in thyroparathyroidectomized hypermagnesemic dogs. Increased serum Mg++ levels had no effect on the phosphaturia produced by the infusion of dibutyryl cAMP to thyroparathyroidectomized dogs. In vitro studies using rat renal cortical slices revealed a progressive decrease in cAMP production in response to PTH as the Mg++ concentrations were increased in the incubation medium. The overall results indicate that hypermagnesemia inhibits the phosphaturic response to PTH by decreasing the renal production of cAMP. Plasma magnesium, therefore, may participate in a double feedback mechanism, not only controlling the release of PTH, but also altering the biological activity of the hormone at the level of the target organ.


Assuntos
Rim/fisiologia , Magnésio/sangue , Hormônio Paratireóideo/fisiologia , Adenilil Ciclases/metabolismo , Animais , AMP Cíclico/biossíntese , AMP Cíclico/urina , Cães , Feminino , Fosfatos/urina
15.
Int J Lab Hematol ; 38(5): 535-42, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27339814

RESUMO

INTRODUCTION: Alpha-thalassemia (α-thal) is a common monogenic disorder worldwide. In mixed ethnic populations, α-thal and beta-thalassemia (ß-thal) can be expected, sometimes giving complex phenotypes, which without molecular analysis are not easily explained. We performed the molecular identification of α- and ß-thal alleles in 51 Mexican patients with microcytosis, hypochromia, and normal or low levels of HbA2 . METHODS: Common deletional alleles (-α(3.7) , -α(4.2) , - -(SEA) , - -(MED) , - -(FIL) , - -(THAI) , -α(20.5) ) and α-triplication were studied by gap-PCR and nondeletional alleles (α(IVSI) ((-5nt)) , α2 (NcoI) , α1 (NcoI) ) by ARMS. ß-thal alleles Cd39 (C>T), IVS1:1 (G>A), IVS1:110 (G>A), and Spanish δß-thal were also investigated. DNA sequencing was performed on HBA2, HBA1, and HBB genes. Negative samples were subjected to MLPA. RESULTS: In 35 subjects, we identified the mutations, -α(3.7) , - -(SEA) , - -(FIL) , α(IVSI) ((-5nt)) , and ααα(anti3.7) and two novel deletion alleles - -(Mex1) (6.8-8.9 kb) and - -(Mex2) (77.6-135.7 kb). Four individuals also had a ß-thal allele (Cd39/IVS1:110). No α-thal alleles were observed in 16 subjects, but three had a ß-thal mutation Cd39, IVS1:110, and Spanish δß-thal. CONCLUSION: α-thal is relatively common in Mexican patients, the combination with ß-thal is sometimes unexpected, and this underlines the importance of performing molecular analysis for both α- and ß-genes defects in patients showing microcytic hypochromic anemia.


Assuntos
Alelos , Anemia Hipocrômica/genética , Sequência de Bases , Hemoglobinas Glicadas/genética , Hemoglobinas Anormais/genética , Deleção de Sequência , Talassemia alfa/genética , Talassemia beta/genética , Feminino , Humanos , Masculino , México
16.
Actas Urol Esp ; 39(4): 236-42, 2015 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25435403

RESUMO

INTRODUCTION: Extracorporeal Shock Wave Lithotripsy (ESWL) is currently the recommended treatment for intra-renal calculi smaller than 2 cm. However the low Stone Free Rate (SFR) in lower pole calculi gives rise to new techniques, such us retrograde intrarenal surgery (RIRS), for improve the surgery outcomes. OBJECTIVE: To compare the efficacy of a treatment with ESWL with RIRS, in terms of SFR after surgery, in patients with kidney stones up to 15 mm in the lower pole. MATERIAL AND METHODS: A prospective study was carried out in order to assess the results of ESWL and RIRS in patients with lower pole stones less than 15 mm. Among a total of 55 patients, 31 were underwent to ESWL (Group 1) and the remaining 24 to RIRS (Group 2). Clinical data recorded, including general characteristics of each patient, were: calculi size, side, operative time, complications according to Clavien scale, SFR and the presence of residual fragments at 2 months post-treatment assessed by a CT scan. STATA 11 was used to perform the statistical analysis. RESULTS: There were no differences for general descriptors among groups with the exception of a significantly longer operative time for RIRS. The rates of SFR and residual fragments lesser than 3 mm. were lower in the RIRS group than in ESWL ones. RIRS also showed a lower rate of clinically significant fragments (0% vs 42.3%. P < .05). In the subgroup of patients with stones between 10/15 mm RIRS showed higher SFR (75% vs. 41.2%) and a lower rate of stones>3 mm (0% vs. 58.8%), being statistically significant (P < .05). Clavien III or higher complications were not reported in any of the groups. CONCLUSIONS: In the treatment of lower pole stone RIRS has the same results than ESWL in terms of SFR. Regarding absence of a clinically significant residual fragment, RIRS was superior to ESWL. A bigger sample size is required in order to confirm this results.


Assuntos
Litotripsia , Ureteroscopia/métodos , Adulto , Feminino , Humanos , Cálculos Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Resultado do Tratamento
17.
J Clin Endocrinol Metab ; 80(7): 2014-20, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7608248

RESUMO

Since 1986, prenatal diagnosis and treatment of congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21-OHD) have been carried out in 239 pregnancies. In 145, diagnoses were made by amniocentesis, whereas 77 were diagnosed using chorionic villus sampling. A newly developed, rapid allele-specific polymerase chain reaction was used for DNA analysis in some cases. Of 239 pregnancies evaluated, 37 babies were affected with classical 21-OHD. Of these, 21 were females, 13 of whom were treated prenatally with dexamethasone. Dexamethasone administered at or before 10 weeks gestation (9 affected female fetuses) was effective in reducing virilization. Seven fetuses had affected female siblings (Prader stages 1-5); 3 of these were born with entirely normal female genitalia, whereas the other 4 were significantly less virilized (Prader stages 1-2) than their siblings. The remaining 2 newborns had male siblings; 1 was born with normal genitalia, and the other was Prader stage 1. No significant or enduring side-effects were noted in either the mothers or the fetuses, indicating that dexamethasone treatment is safe. Prenatally treated newborns did not differ in weight, length, or head circumference from untreated unaffected newborns. Based on our experience, proper prenatal diagnosis and treatment of 21-OHD is effective in significantly reducing or eliminating virilization in the affected female. This spares the newborn female the consequences of genital ambiguity, i.e. genital surgery, sex misassignment, and gender confusion.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/terapia , Dexametasona/uso terapêutico , Mutação , Diagnóstico Pré-Natal , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/embriologia , Amniocentese , Análise de Variância , Feminino , Aconselhamento Genético , Teste de Histocompatibilidade , Humanos , Recém-Nascido , Masculino , Linhagem , Gravidez , Estudos Retrospectivos
18.
J Clin Endocrinol Metab ; 80(5): 1635-40, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7745011

RESUMO

Rapid DNA analysis based on allele-specific polymerase chain reaction (PCR) using mutation site-specific primers was developed to detect mutations in the CYP21 gene known to cause steroid 21-hydroxylase deficiency. In contrast to the previous method, in which PCR of genomic DNA was followed by dot blot analysis with radioactive probes and multiple rounds of stripping and reprobing for each of the 8 most common mutation sites, the results using this new method were immediately visualized after the PCR run by ethidium bromide-stained agarose gel electrophoresis. Using allele-specific PCR, mutation(s) were identified on 148 affected chromosomes out of 160 tested. Although mutation(s) were identified on only one chromosome of 11 of these patients, their parents showed a consistent pattern on DNA analysis. The only exception was that in one family, in which the parents each had a detectable mutation, a mutation was detected on only one allele of the patient. Most likely there is a mutation in the patient's other allele that could have arisen de novo or was inherited from the parent and was not evident in the transmitting parent's phenotype. When compared with the dot blot procedure, allele-specific PCR is more rapid, less labor-intensive, and avoids the use of radioactivity.


Assuntos
Alelos , DNA/genética , Genes , Mutação , Reação em Cadeia da Polimerase/métodos , Esteroide 21-Hidroxilase/genética , Sequência de Bases , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , Fatores de Tempo
19.
J Clin Endocrinol Metab ; 80(8): 2322-9, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7629224

RESUMO

Steroid 21-hydroxylase deficiency is the most frequent cause of congenital adrenal hyperplasia. We have determined the 21-hydroxylase genotype in 197 patients with congenital adrenal hyperplasia owing to 21-hydroxylase deficiency and assessed phenotypic characteristics based on 1) genital status with respect to virilization in females, 2) ACTH stimulation tests to evaluate the secretion of androgens and 17-hydroxyprogesterone, and 3) salt deprivation tests to precisely describe the phenotype with respect to aldosterone deficiency and salt wasting. After dividing our patients into 26 21-hydroxylase gene mutation-identical groups, we found that, in general, the patient's phenotype matched the severity of the genotype. However, in 13 of these groups, the genotype did not always predict the phenotype, even within families. This study, has demonstrated that the 10 most common mutations observed in the 21-hydroxylase gene result in phenotypes that are not always concordant with the genotype.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Mutação , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/fisiopatologia , Adulto , Aldosterona/deficiência , Alelos , Pré-Escolar , Feminino , Genótipo , Humanos , Recém-Nascido , Masculino , Fenótipo , Análise de Regressão , Virilismo/genética , Virilismo/fisiopatologia
20.
Hypertension ; 31(4): 1002-6, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9535427

RESUMO

The purpose of the present study was to analyze the long-term regulation of renal bumetanide-sensitive Na+-K+-2Cl- cotransporter and thiazide-sensitive Na+-Cl- cotransporter gene expression during changes in NaCl and water metabolism. Male Wistar rats exposed to high or low NaCl intake, saline loading, dehydration, water loading, and furosemide administration during 7 days were studied. Control groups had access to regular food and tap water. Rats were kept in metabolic cages for 4 days before and during the experiment to determine daily urinary electrolyte excretion and osmolarity. At the end of the experiment, creatinine clearance and serum electrolyte levels were also measured. Kidneys were excised and macroscopically subdivided into cortex and outer and inner medulla. Total RNA was extracted from each individual cortex or outer medulla by use of the guanidine/cesium chloride method. The Na+-K+-2Cl- cotransporter expression in outer medulla total RNA was assessed by nonradioactive Northern blot analysis and the Na+-Cl- cotransporter expression in renal cortex total RNA was assessed by semiquantitative polymerase chain reaction. Experimental maneuvers were adequately tolerated, and all groups developed the appropriate renal response to each challenge. However, the level of expression of both cotransporters did not change in any model, except for a 2.8-fold increase in the Na+-Cl- cotransporter expression during dehydration. We conclude that nephron adaptation to 7-day modifications in NaCl and water metabolism does not include changes in the amount of electroneutral sodium-coupled cotransporter gene expression at the mRNA level.


Assuntos
Bumetanida/farmacologia , Proteínas de Transporte/efeitos dos fármacos , Diuréticos/farmacologia , Rim/metabolismo , RNA Mensageiro/metabolismo , Cloreto de Sódio/metabolismo , Simportadores , Animais , Benzotiadiazinas , Proteínas de Transporte/metabolismo , Transporte de Íons/efeitos dos fármacos , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Inibidores de Simportadores de Cloreto de Sódio/farmacologia , Simportadores de Cloreto de Sódio , Simportadores de Cloreto de Sódio-Potássio , Água/metabolismo
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