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AIMS: To evaluate the percentage of women with untreated fasting hyperglycaemia in early pregnancy who develop gestational diabetes mellitus after 22 weeks' gestation, the determinants of gestational diabetes development in such women and the prognosis of early fasting hyperglycaemia according to whether the women go on to develop gestational diabetes. METHODS: From a large cohort of women who delivered in our hospital between 2012 and 2016, we retrospectively selected all those who had untreated early fasting hyperglycaemia and separated them into a 'gestational diabetes' and a 'no-gestational diabetes' group according to oral glucose tolerance test results after 22 weeks' gestation. We compared the incidence of a predefined composite outcome (preeclampsia or large-for-gestational-age infant or shoulder dystocia or neonatal hypoglycaemia) in both groups. RESULTS: A total of 268 women (mean fasting plasma glucose 5.3 ± 0.3 mmol/l at a mean ± sd of 10.2 ± 4.2 weeks' gestation) were included. Gestational diabetes developed in 134 women and was independently associated with early fasting plasma glucose ≥ 5.5 mmol/l [odds ratio 3.16 (95% CI 1.57, 6.33)], age ≥ 30 years [odds ratio 2.78 (95% CI 1.46, 5.31)], preconception obesity [odds ratio 2.12 (95% CI 1.11, 4.02)], family history of diabetes [odds ratio 1.87 (95% CI 1.00, 3.50)] and current employment [odds ratio 0.46 (95% CI 0.26, 0.83)]. Despite treatment, gestational diabetes induced a significant increase in the composite outcome as compared to no gestational diabetes (odds ratio 2.16 [95% CI 1.08, 4.34]). The association disappeared after adjustment for risk factors. CONCLUSIONS: Only half of the women with early fasting hyperglycaemia and no specific care subsequently developed gestational diabetes, and these women had a poor prognosis despite gestational diabetes treatment. Poor prognosis was mostly attributable to risk factors. Our results suggest that only women with certain risk factors should be screened for early fasting hyperglycaemia.
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Glicemia/metabolismo , Diabetes Gestacional/diagnóstico , Jejum/metabolismo , Hiperglicemia/diagnóstico , Adulto , Estudos de Casos e Controles , Diabetes Gestacional/epidemiologia , Feminino , Idade Gestacional , Humanos , Hiperglicemia/epidemiologia , Paris , Gravidez , Complicações na Gravidez , Resultado da Gravidez , Prognóstico , Fatores de RiscoRESUMO
OBJECTIVES: 'Hub-and-spoke' networks may be one solution to reduce the geographical inequality in access to liver transplantation (LT) and the growing demands on, and saturation of, LT centres. It is not clear if such networks improve equity of access, deliver comparable patient outcomes or effect patient satisfaction. STUDY DESIGN: Retrospective evaluation of outcomes and patient satisfaction within the Royal Free liver transplant 'hub-and-spoke' network. METHODS: Patient outcomes in those assessed for LT between September 2011 and 2014 at spoke centres (n = 4) were compared retrospectively with those assessed at the LT hub centre. Patient satisfaction questionnaires were completed and changes in LT referral patterns were explored with data obtained directly from NHS Blood and Transplant (NHSBT). RESULTS: A total of 655 patients (180 spoke; 475 hub) were assessed for LT. Patients referred from spoke centres were more likely to have viral hepatitis as an underlying aetiology (72/180 vs 110/475; P < 0.001), or hepatocellular carcinoma (48/180 vs 60/475; P < 0.001) as an indication for LT and were more likely to be listed for LT when compared with hub patients (139/180 vs 312/475, P = 0.005). Mortality on the waiting list (9/123 vs 25/269, P = 0.57), waiting time to LT (64-days vs 78-days, P = 0.91) and Model for End-Stage liver disease (MELD)/United Kingdom End-Stage Liver Disease (UKELD) score (P = 0.24/0.26) in listed patients were equivalent as were 1- and 3-year patient and graft survival rates. Patient satisfaction rates were high at both types of centre, with significantly more patients preferring 'locally delivered care' at spoke vs hub (11/50 vs 70/73, P≤0.0001). Since the development of formal hub-and-spoke networks data from NHSBT based on postcode confirmed a significant increase in patients undergoing LT (153%) from spoke centres, whereas numbers assessed and transplanted from the hub centre have remained static. CONCLUSION: Hub-and-spoke LT networks are effective in offering equivalent clinical outcomes, high patient satisfaction and alleviate clinical pressure on the hub centre. They have to potential to help eliminate the geographical disparity in mortality rates from chronic liver disease.
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Atenção à Saúde/organização & administração , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Hospitais , Transplante de Fígado/estatística & dados numéricos , Modelos Organizacionais , Adolescente , Adulto , Idoso , Feminino , Humanos , Hepatopatias/mortalidade , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Reino Unido/epidemiologia , Listas de Espera/mortalidade , Adulto JovemRESUMO
Bovine tuberculosis is still prevalent and under-evaluated in cattle destined for human consumption in Cameroon. Potential reservoirs of the disease include livestock imported from countries endemic for bovine tuberculosis, such as Nigeria and Chad, and potential residual reservoirs in local livestock and wildlife. Few studies have been done in Cameroon to genotype the Mycobacterium tuberculosis complex (MTC) strains responsible for bovine tuberculosis. The aim of this work is to describe the population structure of MTC strains isolated from cattle, using spoligotyping as the genotyping method. Out of 218 organs or tissues from cattle with suspected tuberculosis lesions, 90 MTC strains were isolated and underwent molecular typing; among them, 86 strains were identified as M. bovis and four strains as M. tuberculosis. The M. tuberculosis strains belonged to rare M. tuberculosis lineages of the U family; among the M. bovis strains SB0944 was the most prevalent. Eight new spoligotype patterns were identified, representing 33% (30/90) of all isolates. Among these new spoligotypes, SB1955 was dominant. The spoligotype patterns of 85 M. bovis strains lacked spacer 30, a common characteristic of the M. bovis lineage African 1, described earlier in Cameroon, Chad, Mali and Nigeria. This study shows ongoing tuberculosis transmission involving M. bovis lineages not previously described as the leading cause of disease. It also shows a possible reverse zoonosis from humans to cattle.
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Matadouros , Mycobacterium bovis/genética , Tuberculose Bovina/microbiologia , Animais , Camarões/epidemiologia , Bovinos , Genótipo , Mycobacterium bovis/isolamento & purificação , Tuberculose Bovina/epidemiologiaRESUMO
We report the observation of the Fermi energy controlled redirection of the ballistic electron flow in a three-terminal system based on a small (100 nm) triangular quantum dot defined in a two-dimensional electron gas (2DEG). Measurement shows strong large-scale sign-changing oscillations of the partial conductance coefficient difference G(21) - G(23) on the gate voltage in zero magnetic field. Simple formulas and numerical simulation show that the effect can be explained by quantum interference and is associated with weak asymmetry of the dot or inequality of the ports connecting the dot to the 2DEG reservoirs. The effect may be strengthened by a weak perpendicular magnetic field. We also consider an additional three-terminal system in which the direction of the electron flow can be controlled by the voltage on the scanning gate microscopy (SGM) tip.
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Transporte de Elétrons , Pontos Quânticos , Semicondutores , Condutividade Elétrica , Teoria QuânticaRESUMO
Exposure to smoke is associated with the development of diseases of the airways and lung parenchyma. Apart from chronic obstructive pulmonary disease (COPD), in some individuals, tobacco smoke can also trigger mechanisms of interstitial damage that result in various pathological changes and pulmonary fibrosis. A causal relation has been established between tobacco smoke and a group of entities that includes respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), desquamative interstitial pneumonia (DIP), Langerhans cell histiocytosis (LCH), and acute eosinophilic pneumonia (AEP). Smoking is considered a risk factor for idiopathic pulmonary fibrosis (IPF); however, the role and impact of smoking in the development of this differentiated clinical entity, which has also been called combined pulmonary fibrosis and emphysema (CPFE) as well as nonspecific interstitial pneumonia (NIP), remains to be determined. The definition of smoking-related interstitial fibrosis (SRIF) is relatively recent, with differentiated histological characteristics. The likely interconnection between the mechanisms involved in inflammation and pulmonary fibrosis in all these processes often results in an overlapping of clinical, radiological, and histological features in the same patient that can sometimes lead to radiological patterns of interstitial lung disease that are impossible to classify. For this reason, a combined approach to diagnosis is recommendable. This combined approach should be based on the joint interpretation of the histological and radiological findings while taking the clinical context into consideration. This paper aims to describe the high-resolution computed tomography (HRCT) findings in this group of disease entities in correlation with the clinical manifestations and histological changes underlying the radiological pattern.
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Doenças Pulmonares Intersticiais , Fibrose Pulmonar , Poluição por Fumaça de Tabaco , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/etiologia , Pulmão/patologia , Fumar/efeitos adversosRESUMO
Ratchet based microwave current generators and detectors were developed in Si/SiGe heterostructures for wireless communication with the possibility of extending the detection limit to the terahertz range. A microwave induced ratchet current was generated in the two-dimensional electron gas by patterning an array of semicircular antidots in hexagonal geometry. The spatial asymmetry created by the semicircular antidots forces the electrons under the influence of the microwave electric field to move preferentially towards the direction of the semidisc axis. A photovoltage of the order of few millivolts was observed. Such a photovoltage was completely absent in a symmetric system consisting of circular antidots. The induced photovoltage increased monotonically with microwave power and was found to be independent of the microwave polarization. This device opens the possibility of employing silicon based heterostructures for nanogenerators and other wireless communication devices using microwaves.
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AIM: To evaluate whether the initial care of women with fasting plasma glucose (FPG) levels at 5.1-6.9mmol/L before 22 weeks of gestation (WG), termed 'early fasting hyperglycaemia', is associated with fewer adverse outcomes than no initial care. METHODS: A total of 523 women with early fasting hyperglycaemia were retrospectively selected in our department (2012-2016) and separated into two groups: (i) those who received immediate care (n=255); and (ii) those who did not (n=268), but had an oral glucose tolerance test (OGTT) at or after 22 WG, with subsequent standard care if hyperglycaemia (by WHO criteria) was present. The number of cases of large-for-gestational age (LGA) infants, shoulder dystocia and preeclampsia with initial care of early fasting hyperglycaemia were compared after propensity score modelling and accounting for covariates. RESULTS: Of the 268 women with no initial care, 134 had hyperglycaemia after 22 WG and then received care. Women who received initial care vs those who did not were more likely to be insulin-treated during pregnancy (58.0% vs 20.9%, respectively; P<0.00001), gained less gestational weight (8.6±5.4kg vs 10.8±6.1kg, respectively; P<0.00001), had a lower rate of preeclampsia [1.2% vs 2.6%, respectively; adjusted odds ratio (aOR): 0.247 (0.082-0.759), P=0.01], and similar rates of LGA infants (12.2% vs 11.9%, respectively) and shoulder dystocia (1.6% vs 1.5%, respectively). When initial FPG levels were ≥5.5mmol/L (prespecified group, n=137), there was a lower rate of LGA infants [6.7% vs 16.1%, respectively; aOR: 0.332 (0.122-0.898); P=0.03]. CONCLUSION: Treating women with early fasting hyperglycaemia, especially when FPG is ≥5.5mmol/L, may improve pregnancy outcomes, although this now needs to be confirmed by randomized clinical trials.
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Glicemia , Diabetes Gestacional , Jejum , Hiperglicemia , Glicemia/metabolismo , Diabetes Gestacional/terapia , Jejum/sangue , Feminino , Humanos , Hiperglicemia/terapia , Gravidez , Resultado da Gravidez , Prognóstico , Estudos RetrospectivosRESUMO
The aim of our study was to investigate whether interleukin (IL)-8 activates systemic coagulation after talc pleurodesis in malignant pleural effusion (MPE), and whether levels of IL-8 in plasma are related to early death after talc pleurodesis. IL-8 and tumour necrosis factor (TNF)-alpha were measured in samples from 231 MPE patients before and after talc pleurodesis. Whole blood from 31 healthy volunteers was incubated with IL-8, TNF-alpha and thromboplastin for 3 h in vitro, and thrombin-antithrombin (TAT) levels were measured. The same stimulation of blood samples was repeated using doses of calibrated talc. Nine, 12 and 17 patients died within 7, 10 and 15 days respectively. IL-8 was elevated in 102 patients within 48 h, and thrombotic events were observed in six of those patients. Survival correlated inversely with IL-8 at 24 and 48 h, and a significant correlation was also found between IL-8 and TAT. A positive dose-dependent correlation with TAT production was observed when blood was stimulated with IL-8 in vitro. However, there was no significant response to stimulation with talc, as compared with control blood samples. IL-8 is involved in the activation of coagulation that may occur after talc pleurodesis, and might also be implicated in early death of patients with MPE.
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Coagulação Sanguínea , Interleucina-8/fisiologia , Derrame Pleural Maligno/mortalidade , Derrame Pleural Maligno/terapia , Pleurodese , Talco/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Interleucina-8/sangue , Masculino , Pessoa de Meia-Idade , Derrame Pleural Maligno/sangue , Taxa de Sobrevida , Adulto JovemRESUMO
Magnetotransport measurements on a high-mobility electron bilayer system formed in a wide GaAs quantum well reveal vanishing dissipative resistance under continuous microwave irradiation. Profound zero-resistance states (ZRS) appear even in the presence of additional intersubband scattering of electrons. We study the dependence of photoresistance on frequency, microwave power, and temperature. Experimental results are compared with a theory demonstrating that the conditions for absolute negative resistivity correlate with the appearance of ZRS.
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We study the transport properties of HgTe-based quantum wells containing simultaneously electrons and holes in a magnetic field B. At the charge neutrality point (CNP) with nearly equal electron and hole densities, the resistance is found to increase very strongly with B while the Hall resistivity turns to zero. This behavior results in a wide plateau in the Hall conductivity sigma(xy) approximately = 0 and in a minimum of diagonal conductivity sigma(xx) at nu = nu(p) - nu(n) = 0, where nu(n) and nu(p) are the electron and hole Landau level filling factors. We suggest that the transport at the CNP point is determined by electron-hole "snake states" propagating along the nu = 0 lines. Our observations are qualitatively similar to the quantum Hall effect in graphene as well as to the transport in a random magnetic field with a zero mean value.
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AIM: Our study evaluated the performance of a selective screening strategy for hyperglycaemia in pregnancy (HIP) based on the presence of risk factors (RFs; body mass index≥25kg/m2, age≥35years, family history of diabetes, personal history of HIP or macrosomic infant) to diagnose HIP and to predict HIP-related events. METHODS: Women with no known diabetes who had undergone complete universal screening (early, before 22weeks of gestation and, if normal, in the second part of pregnancy) at our department (2012-2016) were selected, resulting in four groups of women according to the presence of HIP and/or RFs, with a predefined composite endpoint (preeclampsia or large-for-gestational-age infant or shoulder dystocia). RESULTS: Included were 4518 women: 23.5% had HIP and 71.1% had at least one RF. The distribution among our four groups was: HIP-/RF- (n=1144); HIP-/RF+ (n=2313); HIP+/RF- (n=163); and HIP+/RF+ (n=898). HIP was more frequent when RFs were present rather than absent (33.1% vs 15.4%, respectively; P<0.001). Incidence of the composite endpoint differed significantly (P<0.0001) across groups [HIP-/RF- 6.3%; HIP-/RF+ 13.2%; HIP+/RF- 8.6%; and HIP+/RF+ 17.1% (HIP effect: P<0.05; RF effect: P<0.001; interaction HIP * RF: P=0.94)] and significantly increased with the number of RFs (no RF: 6.3%, 1 RF: 10.8%, 2 RFs: 14.7%, 3 RFs: 28.0%, 4-5 RFs: 25.0%; P<0.0001). CONCLUSION: RFs are predictive of HIP, although 15.4% of women with HIP have no RFs. Also, irrespective of HIP status, RFs are predictive of HIP-related events, suggesting that overweight/obesity, the only modifiable RFs, could be targets of interventions to improve pregnancy prognosis.
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Diabetes Gestacional/diagnóstico , Macrossomia Fetal/epidemiologia , Idade Materna , Obesidade Materna/epidemiologia , Pré-Eclâmpsia/epidemiologia , Diagnóstico Pré-Natal/métodos , Distocia do Ombro/epidemiologia , Adulto , Cesárea , Diabetes Gestacional/epidemiologia , Feminino , França/epidemiologia , Ganho de Peso na Gestação , Teste de Tolerância a Glucose , Humanos , Unidades de Terapia Intensiva Neonatal , Anamnese , Gravidez , Gravidez em Diabéticas/diagnóstico , Gravidez em Diabéticas/epidemiologia , Nascimento Prematuro/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Medição de Risco , Fatores de RiscoRESUMO
We investigate the photoresistance of a magnetically confined quantum wire in which microwave-coupled edge channels interfere at two pinning sites in the fashion of a Mach-Zehnder interferometer. The conductance is strongly enhanced by microwave power at B = 0 and develops a complex series of oscillations when the magnetic confinement increases. Both results are quantitatively explained by the activation of forward scattering in a multimode magnetically confined quantum wire. By varying the strength of the magnetic confinement we are able to tune the phase of electrons in the arms of the interferometer. Quantum interferences which develop between pinning sites explain the oscillations of the conductance as a function of the magnetic field. A fit of the data gives the distance between pinning sites as 11 µm. This result suggests that quantum coherence is conserved over a distance three times longer than the electron mean free path.
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AIMS: In addition to screening for hyperglycaemia during pregnancy after 24 weeks of gestation (WG), the current guidelines also suggest screening in early pregnancy and referring women with early gestational diabetes mellitus (eGDM) or overt diabetes (OD) for immediate care. Our aim was to evaluate this strategy. METHODS: This study evaluated, at our hospital (2012-2016), whether the incidence of a predefined composite outcome (preeclampsia, large-for-gestational-age infant, shoulder dystocia) and secondary outcomes was different when women were screened only after 22WG ('late screening only') or before 22WG and treated for eGDM or OD if present, with repeat screening after 22WG if absent ('early ± late screening'). RESULTS: Early ± late screening (n = 4605, 47.0%) increased between 2012 and 2016 (P < 0.0001) and was associated with more risk factors for GDM than late screening only. Glycaemic status differed in both groups (early ± late screening: eGDM 10.3%, GDM 12.1%, OD 0.9% vs. late screening only: GDM 16.8%, OD 1.2%; P < 0.001), with a higher rate of insulin therapy (8.9% vs. 6.0%; P < 0.001) and less gestational weight gain (11.1 ± 5.4 kg vs. 11.4 ± 5.5 kg; P = 0.013) in the early ± late screening group. Rates of those meeting the composite criterion were similar in both groups [11.6% vs. 12.0%, respectively; odds ratio (OR): 1.040, 95% confidence interval (CI): 0.920-1.176; P = 0.53] and remained comparable after adjusting for Propensity Scores (OR: 1.046, 95% CI: 0.924-1.185; P = 0.4790). Rates for secondary outcomes were also similar in both groups. CONCLUSION: While a strategy including early measurement of fasting plasma glucose during pregnancy increases the incidence and care of hyperglycaemia during pregnancy, it may not significantly improve pregnancy outcomes.
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Diabetes Gestacional/diagnóstico , Teste de Tolerância a Glucose , Resultado da Gravidez , Adulto , Feminino , Humanos , Programas de Rastreamento , GravidezRESUMO
BACKGROUND: Glioblastomas (GBMs) induce a peritumoural vasogenic oedema impairing functional status and quality of life. Steroids reduce brain tumour-related oedema but are associated with numerous side-effects. It was reported in a retrospective series that angiotensin receptor blockers might be associated with reduced peritumoural oedema. The ASTER study is a randomised, placebo-controlled trial to assess whether or not the addition of Losartan to standard of care (SOC) can reduce steroid requirement during radiotherapy (RT) in patients with newly diagnosed GBM. PATIENTS AND METHODS: Patients with a histologically confirmed GBM after biopsy or partial surgical resection were randomised between Losartan or placebo in addition to SOC with RT and temozolomide (TMZ). The primary objective was to investigate the steroid dosage required to control brain oedema on the last day of RT in each arm. The secondary outcomes were steroids dosage 1 month after the end of RT, assessment of cerebral oedema on magnetic resonance imaging, tolerance and survival. RESULTS: Seventy-five patients were randomly assigned to receive Losartan (37 patients) or placebo (38 patients). No difference in the steroid dosage required to control brain oedema on the last day of RT, or one month after completion of RT, was seen between both arms. The incidence of adverse events was similar in both arms. Median overall survival was similar in both arms. CONCLUSIONS: Losartan, although well tolerated, does not reduce the steroid requirement in newly diagnosed GBM patients treated with concomitant RT and TMZ. Trial registration number NCT01805453 with ClinicalTrials.gov.
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Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Neoplasias Encefálicas/terapia , Quimiorradioterapia/mortalidade , Edema/prevenção & controle , Glioblastoma/terapia , Losartan/uso terapêutico , Prednisona/administração & dosagem , Idoso , Anti-Inflamatórios/administração & dosagem , Neoplasias Encefálicas/patologia , Método Duplo-Cego , Quimioterapia Combinada , Edema/epidemiologia , Feminino , Seguimentos , França/epidemiologia , Glioblastoma/patologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Taxa de SobrevidaRESUMO
BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en Y gastric bypass (LRYGB) are commonly performed, but few studies have shown superiority of one strategy over the other. OBJECTIVE: Simultaneously compare LSG and LRYGB in terms of weight loss and morbimortality over a 36-month follow-up period. SETTING: University hospital and bariatric surgery centers, France. METHODS: Prospective, comparative study between LSG and RYGBP. The primary endpoint of this study was a joint hypothesis during the 36-month follow-up: the first primary outcome pertained to the frequency of patients with an excess weight loss (EWL) greater than 50% (% EWL>50%) after LSG or RYGB; the second primary outcome was defined as a composite endpoint of at least one major complication. Secondary objectives were regression of comorbidities and improvement in quality of life. RESULTS: Two hundred and seventy-seven patients were included (91 RYGBP, 186 LSG). The mean age was 41.1±11.1 years, and average preoperative body mass index of 45.3±5.5kg/m2. After 36months, the %EWL>50% was not inferior in the case of LSG (82.2%) relative to LRYGB (82.1%); while major complications rates were significantly higher in LRYGB (15.4%) vs. LSG (5.4%, P=0.005). After 36months, all secondary objectives were comparable between groups while only gastroesophageal reflux disease (GERD) increased in LSG group and decreased in LRYGB group. CONCLUSIONS: LSG was found non-inferior to LRYGB with respect to weight loss and was associated with lower risk of major complications during a 3-year follow-up. But GERD increased in LSG group and decreased in LRYGB group.
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Gastrectomia , Derivação Gástrica , Complicações Pós-Operatórias/epidemiologia , Redução de Peso , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/cirurgia , Dislipidemias/epidemiologia , Dislipidemias/cirurgia , Feminino , Seguimentos , França/epidemiologia , Refluxo Gastroesofágico/epidemiologia , Refluxo Gastroesofágico/cirurgia , Humanos , Hipertensão/epidemiologia , Hipertensão/cirurgia , Masculino , Estudos Prospectivos , Qualidade de Vida , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/cirurgiaAssuntos
Esquistossomose Urinária/epidemiologia , Esquistossomose mansoni/epidemiologia , Animais , Camarões/epidemiologia , Criança , Estudos Transversais , Doenças Endêmicas/estatística & dados numéricos , Fezes/parasitologia , Feminino , Humanos , Enteropatias Parasitárias/epidemiologia , Masculino , Prevalência , Schistosoma haematobium/isolamento & purificação , Schistosoma mansoni/isolamento & purificaçãoRESUMO
A model of a humic substance (MHS) obtained from auto-oxidation of catechol and glycine, was aggregated at pH 6 and 8 with Al(13) polycations. The fate of Al(13) coagulant species upon association with MHS functional groups was studied using solid state (27)Al Magic-angle spinning (MAS) NMR and CP-MAS (13)C NMR. Electrophoretic measurements and steady-state fluorescence spectroscopy with pyrene as a fluoroprobe, were combined to investigate structural re-organization of humic material with aluminum concentration. MAS (27)Al NMR revealed that the coagulant species are Al(13) polycations or oligomers of Al(13) units at both pHs. CP MAS (13)C spectra indicated that, at low Al concentration, hydrolyzed aluminum species bind selectively to carboxylic groups at pH 6 and to phenolic moieties at pH 8. At higher coagulant concentrations, the remaining functional groups also interact with hydrolyzed Al to yield similar CP MAS (13)C spectra in the optimum concentration range. Negative values of electrophoretic mobility were obtained at optimum coagulant concentrations even though an overall charge balance was achieved between MHS anionic charge and Al(13) cationic charge at pH 6. The polarity-sensitive fluorescence of pyrene revealed that the interaction of Al(13) coagulant species with MHS functional groups induces the formation of intramolecular hydrophobic microenvironments. Such structural changes were reversed upon further addition of Al(13) polycations.