RESUMO
Glutaminase plays an important role in carcinogenesis and cancer cell growth. This biological target is interesting against cancer cells. Therefore, in this work, in silico [docking and molecular dynamics (MD) simulations] and in vitro methods (antiproliferative and LC-MS metabolomics) were employed to assay a hybrid compound derived from glutamine and valproic acid (Gln-VPA), which was compared with 6-diazo-5-oxo-L-norleucine (DON, a glutaminase inhibitor) and VPA (contained in Gln-VPA structure). Docking results from some snapshots retrieved from MD simulations show that glutaminase recognized Gln-VPA and DON. Additionally, Gln-VPA showed antiproliferative effects in HeLa cells and inhibited glutaminase activity. Finally, the LC-MS-based metabolomics studies on HeLa cells treated with either Gln-VPA (IC60 = 8 mM) or DON (IC50 = 3.5 mM) show different metabolomics behaviors, suggesting that they modulate different biological targets of the cell death mechanism. In conclusion, Gln-VPA is capable of interfering with more than one pharmacological target of cancer, making it an interesting drug that can be used to avoid multitherapy of classic anticancer drugs.
Assuntos
Antineoplásicos , Glutamina , Ácido Valproico , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Glutaminase/antagonistas & inibidores , Glutaminase/química , Glutamina/química , Glutamina/farmacologia , Células HeLa , Humanos , Espectrometria de Massas , Metaboloma/efeitos dos fármacos , Metabolômica , Modelos Moleculares , Ácido Valproico/química , Ácido Valproico/farmacologiaRESUMO
BACKGROUND: Common variable immunodeficiency (CVID) is a heterogeneous group of primary antibody deficiencies defined by marked reductions in serum IgG, IgA and/or IgM levels and recurrent bacterial infections. Some patients are associated with defects in T cells and regulatory T cells (Tregs), resulting in recurrent viral infections and early-onset autoimmune disease. METHODS: We analyzed whether there is an association between Tregs cells (CD4+CD25+CD127low and CD4+CD25+FoxP3+); memory T cells (CD4+CD45RO+); memory B cells (CD19+CD27-IgD-); and CD21low B cells (CD19+CD38lowCD21low); as well as autoimmune manifestations in 36 patients with CVID (25 women and 11 men, mean age 24 years), all by flow cytometry. RESULTS: Fourteen patients presented with autoimmune diseases (AI) (39%), including 11 with autoimmune thrombocytopenia (ITP) (31%); two with vitiligo (6%); one with systemic lupus erythematosus (LES) (3%); and one with multiple sclerosis (MS) (3%). CVID patients with AI had a reduced proportion of Tregs (both CD4+CD25+CD127low and FoxP3+ cells) compared with healthy controls. CVID patients with AI had expanded CD21low B cell populations compared with patients who did not have AI. A correlation between increased CD4+CD45RO T cell populations and reduced Tregs was also observed. CONCLUSIONS: Our results showed that 39% of patients with CVID had AI and reduced Tregs populations. Research in this area might provide noteworthy data to better understand immune dysfunction and dysregulation related to CVID.
Assuntos
Doenças Autoimunes/metabolismo , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Imunodeficiência de Variável Comum/imunologia , Linfócitos T Reguladores/imunologia , Subpopulações de Linfócitos B/imunologia , Feminino , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Imunofenotipagem , Antígenos Comuns de Leucócito/metabolismo , Masculino , Receptores de Complemento 3d/metabolismo , Adulto JovemRESUMO
The fucosterol has been reported numerous biological activities. In this study, the activity in vitro of the fucosterol from Sargassum horridum as potential human acetylcholinesterase inhibitor was evaluated. The structural identification was obtained by nuclear magnetic resonance (NMR) spectroscopy and based on experimental data, we combined docking and molecular dynamics simulations coupled to the molecular-mechanics-generalized-born-surface-area approach to evaluating the structural and energetic basis for the molecular recognition of fucosterol and neostigmine at the binding site of acetylcholinesterase (AChE). In addition, the Lineweaver-Burk plot showed the nature of a non-competitive inhibition. The maximum velocity (Vmax) and the constant of Michaelis-Menten (Km) estimated for fucosterol (0.006 µM) were 0.015 1/Vo (ΔA/h and 6.399 1/[ACh] mM-1, respectively. While, for neostigmine (0.14 µM), the Vmax was 0.022 1/Vo (ΔA/h) and Km of 6.726 1/[ACh] mM-1, these results showed a more effective inhibition by fucosterol respect to neostigmine. Structural analysis revealed that neostigmine reaches the AChE binding site reported elsewhere, whereas fucosterol can act as a no-competitive and competitive acetylcholinesterase inhibitor, in agree with kinetic enzymatic experiments. Binding free energy calculations revealed that fucosterol reaches the acetylcholinesterase binding site with higher affinity than neostigmine, which is according to experimental results. Whereas the per-residue decomposition free energy analysis let us identify crucial residues involved in the molecular recognition of ligands by AChE. Results corroborate the ability of theoretical methods to provide crucial information at the atomic level about energetic and structural differences in the binding interaction and affinity from fucosterol with AChE. Communicated by Ramaswamy H. Sarma.
Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Sargassum/química , Estigmasterol/análogos & derivados , Sítios de Ligação/efeitos dos fármacos , Humanos , Cinética , Ligantes , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Estigmasterol/farmacologiaRESUMO
2,4-Dichlorophenol (2,4-DCP) is considered a priority pollutant due to its high toxicity. Therefore, it is urgent to develop technologies for the disposal of this pollutant. Various remediation processes have been proposed for the elimination of 2,4-DCP in contaminated water, however, most of them involve high costs of operation and maintenance. This study aimed to determine the capacity of remediation of 2,4-DCP in water by Typha latifolia L. wild plants. For that, the tolerance, removal, accumulation and biotransformation of 2,4-DCP by T. latifolia were investigated. The plants were exposed to 2,4-DCP solutions with a concentration range from 1.5 to 300 mgL-1 for 10 days. They exhibited a reduction in chlorophyll levels and growth rate when 2,4-DCP solutions were ≥30 mgL-1 and ≥50 mgL-1, respectively. The removal of contaminant was dose-depended, being 99.7% at 1.5-3 mgL-1, 59-70% at 10-70 mgL-1 and 35-42% at 100-300 mgL-1 of 2,4-DCP in the solution. Studies indicated that 2,4-DCP was mainly accumulated in root tissue rather than in shoot tissue. Acid hydrolysis of biomass extracts suggests 2,4-DCP bioconjugates formation in root tissue as a response mechanism. Additionally, an increment in glutathione S-transferase (GST) activity could indicate a 2,4-DCP conjugation with glutathione as a detoxification mechanism of T. latifolia.
Assuntos
Biodegradação Ambiental/efeitos dos fármacos , Biotransformação/efeitos dos fármacos , Clorofenóis/toxicidade , Tolerância a Medicamentos , Recuperação e Remediação Ambiental/métodos , Raízes de Plantas/metabolismo , Typhaceae/metabolismo , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/toxicidade , Clorofenóis/isolamento & purificação , Glutationa Transferase/metabolismo , Poluentes Químicos da ÁguaRESUMO
Beta-adrenergic receptor (ßAR)-dependent blood vessel relaxation is impaired in older animals and G protein activation has been suggested as the causative mechanism. Here, we investigated the role of ßAR subtypes (ß1AR, ß2AR, and ß3AR) and cAMP in maturation-dependent vasorelaxation impairment. Aortic rings from 15 Sprague-Dawley male rats (3 or 9 weeks old) were harvested and left intact or denuded of the endothelium. Vascular relaxation in aortic rings from younger and older groups was compared in the presence of ßAR subtype agonists and antagonists along with cAMP and cGMP antagonists. Isolated aortic rings were used to evaluate relaxation responses, protein expression was evaluated by western blot or real time PCR, and metabolites were measured by ELISA. Expression of ßAR subtypes and adenylyl cyclase was assessed, and cAMP activity was measured in vascular tissue from both groups. Isoproterenol- and BRL744-dependent relaxation in aortic rings with and without endothelium from 9-week-old rats was impaired compared with younger rats. The ß1AR antagonist CGP20712A (10-7 M) did not affect isoproterenol or BRL744-dependent relaxation in arteries from either group. The ß2AR antagonist ICI-118,551 (10-7 M) inhibited isoproterenol-dependent aortic relaxation in both groups. The ß3AR antagonist SR59230A (10-7 M) inhibited isoproterenol- and BRL744-dependent aortic ring relaxation in younger but not in older rats. All ßAR subtypes were expressed in both groups, although ß3AR expression was lower in the older group. Adenylyl cyclase (SQ 22536) or protein kinase A (H89) inhibitors prevented isoproterenol-induced relaxation in younger but not in older rats. Production of cAMP was reduced in the older group. Adenylyl cyclase III and RyR3 protein expression was higher in the younger group. In conclusion, altered expression of ß3AR and adenylyl cyclase III may be responsible for reduced cAMP production in the older group.
Assuntos
Inibidores de Adenilil Ciclases/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiopatologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Adenilil Ciclases/fisiologia , Fatores Etários , Albuterol/farmacologia , Animais , Aorta Torácica/fisiologia , Western Blotting , AMP Cíclico/análise , AMP Cíclico/metabolismo , Dobutamina/farmacologia , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Isoproterenol/farmacologia , Masculino , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Receptores Adrenérgicos beta/fisiologia , Valores de Referência , Fatores de TempoRESUMO
BACKGROUND: The non-lethal variant of the Escobar or multiple pterygium syndrome is an entity of autosomal recessive inheritance linked to the X chromosome; it is characterized by multiple pterygia (hence its name) located mainly in the neck (95%) and armpits (55%), as well as other orthopedic malformations such as a vertical talus, congenital hip dislocation, and congenital scoliosis. OBJECTIVE: To present an optional surgical technique for the management of severe spinal deformities. CASE REPORT: Twelve-year-old female diagnosed with Escobar syndrome with severe scoliosis which conditions malformations of the chest with lung involvement, producing mechanical ventilatory restriction and increasing the risk of severe lower respiratory tract infection. We performed a hands-free posterior instrumentation with PASS LP system and Smith-Petersen osteotomies. CONCLUSIONS: The Cobb angle improved from 62° to 23° and the sagittal balance from 125 mm to 73 mm.
El síndrome de Escobar o de pterigium múltiple en su variante no letal es una entidad con tipo de herencia autosómica recesiva ligada al cromosoma X; se caracteriza por presentar múltiples pterigiones de ahí su nombre, principalmente localizados en cuello (95%) y axilas (55%), así como otras malformaciones de tipo ortopédico como astrágalo vertical, luxación congénita de cadera y escoliosis congénita.
Assuntos
Anormalidades Múltiplas , Hipertermia Maligna , Escoliose , Anormalidades da Pele , Fusão Vertebral , Criança , Feminino , Humanos , Hipertermia Maligna/complicações , Escoliose/etiologia , Escoliose/cirurgia , Anormalidades da Pele/complicações , Resultado do TratamentoRESUMO
Beta-adrenergic receptor (βAR)-dependent blood vessel relaxation is impaired in older animals and G protein activation has been suggested as the causative mechanism. Here, we investigated the role of βAR subtypes (β1AR, β2AR, and β3AR) and cAMP in maturation-dependent vasorelaxation impairment. Aortic rings from 15 Sprague-Dawley male rats (3 or 9 weeks old) were harvested and left intact or denuded of the endothelium. Vascular relaxation in aortic rings from younger and older groups was compared in the presence of βAR subtype agonists and antagonists along with cAMP and cGMP antagonists. Isolated aortic rings were used to evaluate relaxation responses, protein expression was evaluated by western blot or real time PCR, and metabolites were measured by ELISA. Expression of βAR subtypes and adenylyl cyclase was assessed, and cAMP activity was measured in vascular tissue from both groups. Isoproterenol- and BRL744-dependent relaxation in aortic rings with and without endothelium from 9-week-old rats was impaired compared with younger rats. The β1AR antagonist CGP20712A (10-7 M) did not affect isoproterenol or BRL744-dependent relaxation in arteries from either group. The β2AR antagonist ICI-118,551 (10-7 M) inhibited isoproterenol-dependent aortic relaxation in both groups. The β3AR antagonist SR59230A (10-7 M) inhibited isoproterenol- and BRL744-dependent aortic ring relaxation in younger but not in older rats. All βAR subtypes were expressed in both groups, although β3AR expression was lower in the older group. Adenylyl cyclase (SQ 22536) or protein kinase A (H89) inhibitors prevented isoproterenol-induced relaxation in younger but not in older rats. Production of cAMP was reduced in the older group. Adenylyl cyclase III and RyR3 protein expression was higher in the younger group. In conclusion, altered expression of β3AR and adenylyl cyclase III may be responsible for reduced cAMP production in the older group.
Assuntos
Animais , Masculino , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiopatologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Antagonistas de Receptores Adrenérgicos beta 1/farmacologia , Inibidores de Adenilil Ciclases/farmacologia , Aorta Torácica/fisiologia , Fatores de Tempo , Expressão Gênica , Adenilil Ciclases/fisiologia , Western Blotting , Fatores Etários , AMP Cíclico/análise , AMP Cíclico/metabolismo , Albuterol/farmacologia , Dobutamina/farmacologiaRESUMO
Oxidative stress is related to the development of central nervous system diseases involving memory processes. Cholinergic system and memory processes are disrupted by ozone exposure. In rats, ozone induces motor disturbances and memory deficits as well as biochemical changes in brain regions related to memory processes. In this work, we analyzed the effect of chronic tibolone (TIB) administration in central nervous system, specifically the content of choline acetyltransferase, acetylcholinesterase, acetylcholine and oxidative stress markers in the hippocampus of male rats exposed to ozone. Our results reveal a neuroprotective effect of TIB treatment on neuronal damage induced by chronic ozone exposure. Furthermore, we suggest that TIB can prevent memory deficits by providing a protective effect against oxidative stress and the cholinergic system disruption induced by ozone exposure. Together, these findings present a potential neuroprotective effect of TIB in processes linked to memory deficits induced by aging or neurodegenerative diseases.
Assuntos
Neurônios Colinérgicos/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Norpregnenos/farmacologia , Ozônio/toxicidade , Animais , Masculino , Oxirredução , Estresse Oxidativo , Ratos , Ratos WistarRESUMO
In Mexico, medicinal plants are widely used. The use of Randia aculeata by healers against snakebites has never been scientifically tested in relation to possible effects on blood parameters and muscle tissue damage. Interviews were carried out in Jamapa, Veracuz, Mexico, with local residents to collect information about the traditional use of Randia aculeata. In this locality, seven pieces of fruit from the plant are mixed in a liter of alcohol, and then administered orally against snakebites. By using histological techniques and a murine model, we explored its cytoprotective properties against the effects of Crotalus simus and Bothrops asper venoms. Possible protections provided by the plant against tissue damage to skeletal and cardiac muscles and against the typical loss of red blood cells were analyzed. Randia aculeata caused an increase in microhematocrit and total hemoglobin, parameters that are often decremented in association with the loss of red blood cells, which is a characteristic effect of animal venom. Randia aculeata was also shown to protect against the lowering of platelet levels caused by Bothrops asper venom. Finally, Randia aculeata produced a partial inhibition of necrosis following administration of snake venom in skeletal and myocardial muscles. The present results provide solid evidence for the traditional use of Randia aculeata against snakebites, as demonstrated by protection against muscular tissue damage and the diminution of red blood cells.(AU)
Assuntos
Animais , Etnobotânica/métodos , Rubiaceae/imunologia , Rubiaceae/metabolismo , Antivenenos/administração & dosagem , Antivenenos/sangue , Antivenenos , Antivenenos/uso terapêutico , Plantas Medicinais , Mordeduras de Serpentes/imunologiaRESUMO
In Mexico, medicinal plants are widely used. The use of Randia aculeata by healers against snakebites has never been scientifically tested in relation to possible effects on blood parameters and muscle tissue damage. Interviews were carried out in Jamapa, Veracuz, Mexico, with local residents to collect information about the traditional use of Randia aculeata. In this locality, seven pieces of fruit from the plant are mixed in a liter of alcohol, and then administered orally against snakebites. By using histological techniques and a murine model, we explored its cytoprotective properties against the effects of Crotalus simus and Bothrops asper venoms. Possible protections provided by the plant against tissue damage to skeletal and cardiac muscles and against the typical loss of red blood cells were analyzed. Randia aculeata caused an increase in microhematocrit and total hemoglobin, parameters that are often decremented in association with the loss of red blood cells, which is a characteristic effect of animal venom. Randia aculeata was also shown to protect against the lowering of platelet levels caused by Bothrops asper venom. Finally, Randia aculeata produced a partial inhibition of necrosis following administration of snake venom in skeletal and myocardial muscles. The present results provide solid evidence for the traditional use of Randia aculeata against snakebites, as demonstrated by protection against muscular tissue damage and the diminution of red blood cells.
Assuntos
Animais , Masculino , Ratos , Antivenenos , Músculos/lesões , Rubiaceae/imunologia , Venenos de Serpentes , Ferimentos e Lesões , EtnobotânicaRESUMO
UNLABELLED: Chronic vascular diseases constitute a growing global health problem. OBJECTIVES: To (a) determine marker positivity for renovascular damage in the total adult population of the Isle of Youth, Cuba; (b) describe marker association with common risk factors for renal and related chronic vascular conditions, and (c) identify best predictors of renovascular damage. METHODS: Previous informed consent was obtained, the population studied was 55,646, and subjects were aged ≥20 years. Blood pressure, weight and height were measured and a questionnaire applied. Urine markers for renovascular damage (hematuria, proteinuria and microalbuminuria) were also determined. RESULTS: Positive markers were detected in 21.3%: hematuria (12.6%), microalbuminuria (6.8%), proteinuria (0.9%), and proteinuria + hematuria (0.9%). Risk factors were highly prevalent: 15.1% were aged ≥60 years; 32.3% overweight, 13.9% obese, and 25.1% smokers. Prevalence of high blood pressure (30%), diabetes mellitus (5.4%) and cardiovascular disease (5%) was also high, while cerebrovascular disease registered 0.9%. Markers were more prevalent in older people and in those suffering from diabetes mellitus, high blood pressure, cardiovascular and cerebrovascular disease, overweight or obesity. Risk factor regression tree analysis identified hypertension as the best predictor of renovascular damage. CONCLUSIONS: Adult population-wide screening revealed hidden morbidity and permitted better risk stratification. Results serve to inform community-based multidisciplinary and intersectoral disease prevention and management.
Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/urina , Nefropatias/diagnóstico , Nefropatias/urina , Adulto , Idoso , Albuminúria/diagnóstico , Albuminúria/etnologia , Albuminúria/urina , Biomarcadores/urina , Doenças Cardiovasculares/etnologia , Cuba/etnologia , Feminino , Humanos , Nefropatias/etnologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Proteinúria/diagnóstico , Proteinúria/etnologia , Proteinúria/urina , Fatores de Risco , Inquéritos e Questionários , Adulto JovemRESUMO
1 The role of the extraendothelial and constitutive isoforms of cyclo-oxygenase-2 (COX-2) in the contractile effect of angiotensin II (Ang II) was investigated using thoracic and abdominal aortic rings without endothelium from young Wistar rats. 2 Ang II elicited similar contractions in both aortic segments, and the effect was inhibited by pretreatment with NS398 (a selective COX-2 inhibitor) but not SC-560 [selective cyclo-oxygenase-1 (COX-1) inhibitor]. 3 COX-2 mRNA was expressed under basal conditions in both aortic segments. Additionally, Ang II increased COX-2 mRNA expression in the abdominal but not the thoracic segment, while cycloheximide (a protein synthesis inhibitor) did not affect the contractile response to Ang II in either of the two segments; this suggests that the effect is not associated with de novo COX-2 synthesis. 4 In conclusion, the basal amount of COX-2 found in aortic smooth muscle cells is sufficient to explain the production of the prostanoids related to the contractile effect of Ang II. The production of these prostanoids, which are derived from constitutive COX-2, occurs independently of the endothelium vascular system.
Assuntos
Angiotensina II/metabolismo , Aorta/metabolismo , Ciclo-Oxigenase 2/metabolismo , Endotélio Vascular/fisiologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Animais , Aorta/efeitos dos fármacos , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/metabolismo , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Endotélio Vascular/efeitos dos fármacos , Técnicas In Vitro , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Especificidade de Órgãos , Concentração Osmolar , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Ratos , Ratos WistarRESUMO
MCM-41 and FSM-16 were used for enzyme immobilization on account of their good physical and chemical properties. In this work, the catalytic activity of acetylcholinesterase (AChE) immobilized on these materials was investigated, using neostigmina as AChE inhibitor. The results show that AChE was adsorbed on MCM-41 and on FSM-16-TIPB. AChE immobilized on the latter material maintained 70% of its activity and the material did not hydrolyze ACh (as MCM-41) by itself. Therefore, FSM-16-TIPB was the best material, considering also that when neostigmine was applied to AChE immobilized on FSM-16-TIPB, the activity of AChE decreased as occurs in its free from. Hence, this model could be useful in the evaluation of different kinds of AChE inhibitors, allowing the recycling of enzymes and making possible several assays and thereby, lowering cost.
Assuntos
Acetilcolinesterase/metabolismo , Enzimas Imobilizadas/metabolismo , Dióxido de Silício/metabolismo , Acetilcolinesterase/química , Adsorção , Animais , Catálise , Bovinos , Enzimas Imobilizadas/química , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Porosidade , Soluções , Espectrofotometria Ultravioleta , Difração de Raios XRESUMO
INTRODUCTION: Gastric lavage is still used in Mexico and other countries without evidence to support this practice. We performed a randomized controlled trial to test the hypothesis that elimination of amniotic fluid from the stomach of the newborn reduces nausea and vomiting and improves tolerance on the first feedings of breast or formula milk. PATIENTS AND METHODS: A randomized, single-blind, controlled trial was conducted in a rural general hospital in the north of Mexico. Eligible healthy term newborns were randomly allocated to receive gastric lavage (n = 63) or observation (n = 61). The primary outcome measures were the presence of nausea and/or emesis in the first 24 hours of life and the breastfeeding failure rate, evaluated by a nurse blinded to the group assignment. RESULTS: Of the 63 patients in the gastric lavage group, 13 had at least one episode of nausea or vomiting compared with 15 out of 61 patients in the control group (relative risk: 0.84; 95 % CI: 0.43 to 1.61). Breastfeeding failure occurred in seven mother-child pairs in the gastric lavage group compared with five in the control group (P = 0.8; relative risk: 0.96; 95 % CI: 0.86 to 1.08). Other variables such as sex or cesarian section rate were unrelated to outcome. There were no complications that could be attributed to the procedure. All the newborn infants were discharged without problems. CONCLUSIONS: Gastric aspiration or lavage in the healthy full-term newborn is a common procedure that should be abandoned as it confers no advantages.
Assuntos
Lavagem Gástrica , Aleitamento Materno , Feminino , Humanos , Recém-Nascido , Masculino , Náusea/prevenção & controle , Método Simples-Cego , Vômito/prevenção & controleRESUMO
The aim of this paper is to estimate the levels of arsenic (As) ingestion through cooked foods consumed in an arsenic endemic area and the assessment of their dietary intake of As. The study was conducted in two villages: a population chronically exposed to a high concentration of As via drinking water (410+/-35 microg/l) and to a low-exposure group (12+/-4 microg/l). A 24-h dietary recall questionnaire was applied to about 25 adult participants in each community. Samples of cooked food, ready for intake, were collected separately from each family's participants. To obtain the As estimate for each food item consumed, the mean quantity of food ingested in grams (wet weight) was calculated and the concentrations of total arsenic (TAs) in each cooked food were determined. The estimations of TAs intake were based on the sum over mean of As ingested from each food item consumed during the 24-h period for each participant. For the estimation of total daily As intake, we summed the mean obtained from food, plain water and hot beverage intakes. The TAs average intakes calculated for low-As-exposure group were 0.94 and 0.76 microg/kg body weight/day, for both summer and winter exposure scenarios, respectively. These values are 44.7 and 36% of the provisional tolerable daily intake (PTDI) for inorganic arsenic (2.14 microg/kg body weight/day), established by the World Health Organization (WHO) in 1989. The WHO reference value was obtained on a weekly basis intake estimation assuming an average body weight of 68 kg in adults. In contrast, for the high-exposure group the TAs average intakes were 16.6 and 12.3 microg/kg body weight/day for summer and winter, respectively. Ingestion via cooked food represented 32.5 and 43.9% of the total daily As intake in the high-exposure group; for summer and winter, respectively. None the less, the bioavailability of As through food can be different than via drinking water.
Assuntos
Arsênio/administração & dosagem , Arsênio/análise , Dieta , Análise de Alimentos , Temperatura Alta , Adulto , Peso Corporal , Exposição Ambiental , Feminino , Humanos , Masculino , Rememoração Mental , Estações do Ano , Inquéritos e Questionários , Água/análiseRESUMO
Thermally stimulated depolarization currents, TSDC, experiments have been performed on a series of poly(styrene)-b-poly(butadiene)-b-poly(epsilon-caprolactone) triblock copolymers SBC with different proportions of the poly(epsilon-caprolactone) crystallizable block, PCL. The morphology of the segregated microphases varies with the PCL content and has been observed by transmission electron microscopy. The crystallinity of the PCL block is estimated by wide angle x-ray scattering, WAXS. The relaxation times distribution is extracted by a numerical decomposition of the TSDC spectra and it is shown that this distribution is not significantly changed on going from the homopolymer to the triblock copolymer with 16 wt % to 77 wt % of PCL in the original samples. Better segregation of the mesophase structure is reached when the samples are annealed at 413 K and important variations in the TSDC and WAXS spectra are observed as a result of the thermal treatment. For the S09B14C77 triblock copolymer the results obtained can be explained by postulating the existence of a rigid amorphous phase in the PCL block. Such rigid amorphous phase is located between the core-shell cylinders formed by the other blocks [with poly(styrene)(PS) as core and poly(butadiene)(PB) as shell] and is constrained by undulated lamellae of crystalline PCL material. In the case of S35B15C50 triblock copolymer, an important amount of diffuse PS-PCL interphase where the homopolymers are mixed must be present before annealing. The results for the material with the less abundant PCL block are explained as a result of the confinement in nanotubes of PCL surrounded by PB embedded in a vitreous PS matrix. Broadband dielectric experiments on these same materials confirm the results obtained by TSDC spectroscopy.
RESUMO
OBJECTIVE: To describe the clinical presentation and treatment of two patients with the Klippel-Trenaunay syndrome referred to our hospital because of rectal bleeding and to review the literature concerning the diagnosis and treatment of this complication. CASE 1: Fifteen year old male with the Klippel-Trenaunay syndrome and chronic anemia who presented with severe rectal bleeding. CASE 2: Nineteen year old female with the same syndrome and a two year history of intermittent rectal bleeding, anemia and thrombocytopenia. In both cases the study protocol revealed varicose lesions in the colon as the cause of bleeding and other vascular malformations related to their syndrome. TREATMENT: The first patient was treated with partial colectomy and colorectal anastomosis. Four years after surgery he presented with new episodes of bleeding and was treated with sclerosis of the residual rectal varices using formaldehyde. The second patient was treated with partial colectomy and colostomy. She has received to sessions of sclerosis with absolute alcohol of the residual varices in the rectal stump. Colostomy closure is soon to be performed. CONCLUSION: Klippel-Trenaunay syndrome is a rare clinical entity with vascular alterations at different levels. A small percentage of cases may present rectal bleeding due to colonic varices and can lead to chronic anemia or severe hemorrhage with hemodynamic implications. Treatment of this complication involves resection of the affected colonic segment combined with a secondary procedure to control bleeding of the residual rectal varices.
Assuntos
Hemorragia Gastrointestinal/etiologia , Síndrome de Klippel-Trenaunay-Weber/complicações , Adolescente , Adulto , Colectomia , Colo/irrigação sanguínea , Colostomia , Desinfetantes/administração & dosagem , Feminino , Formaldeído/administração & dosagem , Hemorragia Gastrointestinal/cirurgia , Humanos , Síndrome de Klippel-Trenaunay-Weber/cirurgia , Masculino , Reto/irrigação sanguínea , Recidiva , Soluções Esclerosantes/administração & dosagem , Varizes/complicações , Varizes/cirurgia , Varizes/terapiaRESUMO
OBJECTIVE: To review the frequency localization, latency and clinical staging of synchronic and methachronic tumors in patients with resected carcinoma of the colon during the period 1979-1989. SETTING: A third level hospital in Mexico City. RESULTS: Synchronic tumors. Nine individuals (7.2%) of 123 patients reviewed had synchronic tumors. Their mean age was 63 years (26-78); 4 were men and 5 women. Localization and staging were: transverse colon + sigmoid (B1 + A); both ascendant colon (C2 + A); transverse colon + rectum(B3 + A); both descendent colon (B2 + A); sigmoid + descendent colon (A + A); transverse + descendent colon (B2 + B2); ascendant + sigmoid colon (D + B2); both sigmoid (B1 + A); ascendant + transverse colon (B1 + B2). In four patients, the presence of the synchronic tumors modified the surgical procedure. Methachronic tumors. Two cases (3.2%) were detected in 61 patients followed more than one year after colonic cancer surgery; the latency times were 16 and 23 months. In one case staging was A and the other was an in situ carcinoma. CONCLUSIONS: The frequency of synchronic and methachronic tumors in similar to that reported in the English literature. We emphasize the need to perform routine control colonoscopies preparatively and during the followup of these patients.
Assuntos
Neoplasias do Colo/patologia , Neoplasias Primárias Múltiplas/patologia , Adulto , Idoso , Neoplasias do Colo/epidemiologia , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/epidemiologia , Estudos RetrospectivosRESUMO
The objective of this study was to search for regional cerebral blood flow (rCBF) abnormalities in adolescents with initial-stage schizophrenia by means of brain single-photon emission tomography (SPET) using technetium-99m hexamethylpropylene amine oxime (HMPAO). SPET studies were performed on a homogeneous sample of 15 carefully selected adolescents with a recent diagnosis of schizophrenia, and without previous electroconvulsive or antipsychotic drug treatment. Computed tomography (CT) and electro-encephalographic (EEG) studies were performed in all patients. Qualitative and semiquantitative analysis of 99mTc-HMPAO SPET studies showed an impaired rCBF in 12 patients (80%). The most common pattern was a decreased uptake of 99mTc-HMPAO in the frontal lobes, usually in the left hemisphere. Conventional and quantitative EEG was positive in 12 (80%) and 15 (100%) patients, respectively. CT findings were positive in two patients (13%). There was a high level of concordance between SPET and EEG results and between SPET and clinical features (P>0.05). This study suggests that previously untreated patients in the first stages of schizophrenia present functional abnormalities that are revealed by brain SPET.
Assuntos
Encéfalo/diagnóstico por imagem , Compostos de Organotecnécio , Oximas , Esquizofrenia/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adolescente , Circulação Cerebrovascular , Eletroencefalografia , Feminino , Humanos , Masculino , Esquizofrenia/fisiopatologia , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada por Raios XRESUMO
La mayoría de los modelos experimentales en cirugía laparoscópica se practican en animales porcino y caninos; algunos inconvenientes que presentan estas especies son alto costo y que requieren de personal especializado para su manejo. La rata, animal ampliamente utilizado en microcirugía (investigación y docencia), es una especie que puede ser empleada en la laparoscopia para adiestramiento especialmente del cirujano pediatra y en la investigación. En el presente trabajo se comparan los resultados obtenidos con la operación de Nissen abierta y con técnica laparoscópica. Se emplearon 24 ratas cepa Wistar de 250 a 300 g de peso anestesiadas con pentotal, las cuales fueron divididas en tres grupos. En el grupo 1 (n =.8) se midió la presión intragástrica necesaria para producir reflujo esofágico (11 mmHg en promedio); en el grupo 2 (n = 8) se efectuó la funduplicatura con técnica abierta y medición de presiones intragástricas hasta obtener reflujo. Al grupo 3 (n = 8) se le determinaron los mismos parámetros después de practicada la funduplicatura por vía laparoscópica. La presión necesaria para producir reflujo fue similar en los grupos 2 y 3 (60 a 80 mmHg). el modelo esperimental diseñado es económico, de fácil montaje si se cuenta con experiencia en las técnicas laparoscópicas donde se emplean dos manos y se ralizan suturas