RESUMO
PURPOSE: Racial disparities have been shown in outcomes and treatment of children with type 1 diabetes (T1D). The purpose of this study was to examine temporal trends in insulin pump use among non-Hispanic white (NHW), non-Hispanic black (NHB) and Hispanic children attending a large urban diabetes center. . This study was a retrospective chart review of insulin pump usage by race (NHW/ NHB) in 2005, and race/ethnicity (NHW/NHB/Hispanic) in 2011-2019. Demographic data (age, sex, diabetes duration, SES) and most recent hemoglobin A1c were also abstracted in 2011-2019. RESULTS: In 2005, NHW children were twice as likely to use an insulin pump as NHB children. From 2011 to 2019, the odds ratio increased to 2.5 for NHW compared to NHB children. The odds of Hispanic children using insulin pumps were also higher than NHB. Insurance status (government versus private), a surrogate for SES, had very little influence on these trends, with NHW children consistently more likely than NHB children to be treated with insulin pumps in 2011, 2013, 2017, 2019 (p < 0.001). CONCLUSIONS: We have demonstrated that racial disparities in insulin pump use have persisted over the past 15 years, and are not determined by SES. This inequity in diabetes treatment may be playing a role in the poorer glycemic control and higher rates of diabetes complications in NHB children. PRACTICE IMPLICATIONS: Healthcare providers should be cognizant of racial and ethnic disparities in the treatment of children with T1D. Standardized treatment protocols may reduce unconscious bias in prescribing.
Assuntos
Diabetes Mellitus Tipo 1 , Negro ou Afro-Americano , Criança , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Humanos , Sistemas de Infusão de Insulina , Estudos Retrospectivos , População BrancaRESUMO
AIM: Counselling patients and their relatives about non-curative management options in colorectal cancer is difficult because of a paucity of published data. This study aims to determine outcomes in patients unsuitable for curative surgery and the rates of subsequent surgical intervention. METHOD: This was an analysis of all colorectal cancers managed without curative surgery in a district general hospital from a prospectively maintained cancer registry between 2009 and 2016, as decided by a multidisciplinary team. Primary outcomes were overall survival and secondary outcomes were subsequent intervention rates and impact of tumour stage. RESULTS: In all, 183 patients out of 976 patients (18.8%) were identified. The median age at diagnosis was 81 years [interquartile range (IQR) 71-87 years]. Overall median survival from diagnosis was 205 days (IQR 60-532 days). One-year mortality was 62.3%. Patients were classified into two groups depending on the reason for a non-curable approach: patient-related (PR) or disease-related (DR). The difference in survival between PR (median 277 days, IQR 70-593) and DR (median 179 days, IQR 51-450) was 98 days (P = 0.023). Twenty-four patients were alive at the end of the study period; 19 out of 91 cases in PR (20.8%) and five out of 92 cases in DR (5.4%). Overall intervention rates were 11.9%, with higher rates in the DR group (P = 0.005). Disease stage was not associated with subsequent surgical intervention between the two groups (P = 0.392). CONCLUSION: Life expectancy for non-curatively managed patients within our unit was 6.8 months with one in nine patients requiring subsequent surgical admission for palliation. This information may be useful when counselling patients with incurable colorectal malignancy.
Assuntos
Neoplasias Colorretais/mortalidade , Gerenciamento Clínico , Cuidados Paliativos/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/terapia , Feminino , Humanos , Expectativa de Vida , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Estudos RetrospectivosRESUMO
This paper presents an overview of global ergonomics standards and guidelines for design of computer workstations, with particular focus on their inconsistency and associated health risk impact. Overall, considerable disagreements were found in the design specifications of computer workstations globally, particularly in relation to the results from previous ergonomics research and the outcomes from current ergonomics standards and guidelines. To cope with the rapid advancement in computer technology, this article provides justifications and suggestions for modifications in the current ergonomics standards and guidelines for the design of computer workstations. Practitioner Summary: A research gap exists in ergonomics standards and guidelines for computer workstations. We explore the validity and generalisability of ergonomics recommendations by comparing previous ergonomics research through to recommendations and outcomes from current ergonomics standards and guidelines.
Assuntos
Terminais de Computador , Ergonomia/normas , Guias como Assunto , Decoração de Interiores e Mobiliário/normas , Saúde Ocupacional , Local de Trabalho/normas , Computadores , HumanosRESUMO
BACKGROUND: The benefits of stroke volume optimization during surgery are unclear, with recent data not replicating the positive effects of earlier studies. METHODS: This was a randomized controlled trial of standard fluid therapy with or without supplementary blinded intraoperative stroke volume optimization in 220 patients having major elective rectal resection or cystectomy with ileal conduit. All patients were treated using a contemporary enhanced recovery pathway. Interventional fluid challenges used Gelofusine (B Braun, Germany), guided by stoke volume variability measured by LiDCOrapid (LiDCO, UK). Participants were stratified by aerobic fitness (characterized by preoperative cardiopulmonary exercise test), surgical specialty, and intended surgical approach (open or laparoscopic). The primary outcome was the prevalence of moderate or severe complications on day 5 after surgery, defined using the postoperative morbidity survey (POMS) criteria. RESULTS: Patients received â¼13 ml kg(-1) h(-1) of i.v. fluids during surgery. The intervention group received an additional mean (sd) 956 (896) ml Gelofusine. There were no statistically significant differences between groups in any primary or secondary end point. A positive POMS on postoperative day 5 was noted in 54 of 111 control subjects (48.6%) and 55 of 109 participants in the intervention group [50.5%; adjusted odds ratio 0.90 (95% confidence interval 0.52-1.57), P=0.717]. Mean (sd) hospital length of stay was 9.6 (6.8) days in the control group and 11.8 (11.5) days in the intervention group (adjusted difference -2.1 (-4.6 to 0.3) days, P=0.091). There was no statistical interaction between stroke volume optimization and aerobic fitness in terms of rate of complications or length of stay. CONCLUSIONS: Algorithm-driven stroke volume optimization is of no benefit when superimposed on a liberal baseline fluid regimen in patients having elective major abdominal surgery, when stratified to minimize differences in fitness and surgical approach between groups. CLINICAL TRIAL REGISTRATION: ISRCTN21597243.
Assuntos
Cirurgia Colorretal , Procedimentos Cirúrgicos Eletivos , Hidratação/métodos , Monitorização Intraoperatória/métodos , Aptidão Física/fisiologia , Volume Sistólico/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Reino Unido/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: Fatty liver disease is commonly associated with obesity, insulin resistance and diabetes. Severe fatty liver is sometimes accompanied by steatohepatitis and may lead to the development of hepatocellular carcinoma. At present, there is no effective treatment for non-alcoholic fatty liver disease (NAFLD); thus, recent investigations have focused on developing effective therapeutics to treat this condition. This study aimed to evaluate the effects of kefir on the hepatic lipid metabolism of ob/ob mice, which are commonly used to model fatty liver disease. RESULTS: In this study, we used leptin receptor-deficient ob/ob mice as an animal disease model of NAFLD. Six-week-old ob/ob mice were orally administered the dairy product kefir (140 mg kg(-1) of body weight (BW) per day) for 4 weeks. The data demonstrated that kefir improved fatty liver syndrome on BW, energy expenditure and basal metabolic rate by inhibiting serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities (P<0.05) and by decreasing the triglyceride (TG) and total cholesterol (TC) contents of the liver (P<0.05). Oral kefir administration also significantly reduced the macrovesicular fat quantity in liver tissue. In addition, kefir markedly decreased the expression of the genes sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (P<0.05) but not the expression of peroxisome proliferator-activated receptor α (PPARα) or hepatic carnitine palmitoyltransferase-1α (CPT1α) in the livers of ob/ob mice. CONCLUSION: On the basis of these results, we conclude that kefir improves NAFLD on BW, energy expenditure and basal metabolic rate by inhibiting the lipogenesis pathway and that kefir may have the potential for clinical application to the prevention or treatment of NAFLD.
Assuntos
Produtos Fermentados do Leite/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Metabolismo Basal , Biomarcadores/metabolismo , Western Blotting , Modelos Animais de Doenças , Metabolismo Energético , Regulação da Expressão Gênica , Metabolismo dos Lipídeos , Camundongos , Camundongos Knockout , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Tamanho do Órgão , Receptores para Leptina/deficiência , Transdução de SinaisRESUMO
OBJECTIVE: To assess the relationship between endometrial/subendometrial vascularity and the risk of pregnancy-induced hypertension (PIH) or small-for-gestational-age (SGA) fetuses in women who had a live birth following in-vitro fertilization (IVF). METHODS: This was a retrospective study of women who had a live birth after IVF from November 2002 to December 2004. Only women with a singleton pregnancy (n = 104) were included for analysis. Three-dimensional ultrasound measurement with power Doppler of the endometrial and subendometrial regions was performed on the day of oocyte retrieval in stimulated IVF cycles or on luteinizing hormone surge + 1 day in frozen-thawed embryo transfer cycles to measure the endometrial volume and the vascularization index (VI), flow index (FI) and vascularization flow index (VFI) of the endometrial and subendometrial regions. Pregnancy outcomes were also reviewed. RESULTS: Eight women (7.7%) had PIH or an SGA fetus. Women in the PIH/SGA group had significantly lower endometrial VI (0.504 vs 1.051; P = 0.023) and VFI (0.121 vs 0.253; P = 0.023) than those in the non-PIH/SGA group. However endometrial FI was significantly higher in the PIH/SGA group (23.04 vs 22.71; P = 0.028). There were no significant differences in subendometrial indices between the two groups. CONCLUSION: Women who had a live birth following IVF and whose pregnancy was complicated by PIH or an SGA fetus had significantly lower endometrial vascularity in terms of VI and VFI than did women without PIH or SGA.
Assuntos
Endométrio/irrigação sanguínea , Endométrio/diagnóstico por imagem , Hipertensão Induzida pela Gravidez/diagnóstico por imagem , Nascido Vivo/epidemiologia , Adulto , Transferência Embrionária , Feminino , Fertilização in vitro/métodos , Idade Gestacional , Humanos , Hipertensão Induzida pela Gravidez/etiologia , Infertilidade Feminina/diagnóstico por imagem , Infertilidade Feminina/etiologia , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Ultrassonografia Doppler/métodosRESUMO
This study aimed to determine the accuracy of large language models (LLMs) in answering oral and maxillofacial surgery (OMS) multiple choice questions. A total of 259 questions from the university's question bank were answered by the LLMs (GPT-3.5, GPT-4, Llama 2, Gemini, and Copilot). The scores per category as well as the total score out of 259 were recorded and evaluated, with the passing score set at 50%. The mean overall score amongst all LLMs was 62.5%. GPT-4 performed the best (76.8%, 95% confidence interval (CI) 71.4-82.2%), followed by Copilot (72.6%, 95% CI 67.2-78.0%), GPT-3.5 (62.2%, 95% CI 56.4-68.0%), Gemini (58.7%, 95% CI 52.9-64.5%), and Llama 2 (42.5%, 95% CI 37.1-48.6%). There was a statistically significant difference between the scores of the five LLMs overall (χ2 = 79.9, df = 4, P < 0.001) and within all categories except 'basic sciences' (P = 0.129), 'dentoalveolar and implant surgery' (P = 0.052), and 'oral medicine/pathology/radiology' (P = 0.801). The LLMs performed best in 'basic sciences' (68.9%) and poorest in 'pharmacology' (45.9%). The LLMs can be used as adjuncts in teaching, but should not be used for clinical decision-making until the models are further developed and validated.
Assuntos
Avaliação Educacional , Cirurgia Bucal , Humanos , Avaliação Educacional/métodos , Idioma , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Surgical patients with poor functional capacity, determined by oxygen consumption at anaerobic threshold (AT) during cardiopulmonary exercise testing (CPET), experience longer hospital stays and worse short- and medium-term survival. However, previous studies excluded patients who were unable to perform a CPET or who failed to demonstrate an AT. We hypothesized that such patients are at risk of inferior outcomes after elective surgery. METHODS: All patients undergoing major colorectal surgery attempted CPET to assist in the planning of care. Patients were stratified by their test results into Fit (AT ≥ 11.0 ml O2 kg(-1) min(-1)), Unfit (AT < 11.0 ml O2 kg(-1) min(-1)), or Unable to CPET groups (failed to pedal or demonstrate an AT). For each group, we determined hospital stay and mortality. RESULTS: Between March 2009 and April 2010, 269 consecutive patients were screened, and proceeded to bowel resection. Median hospital stay was 8 days (IQR 5.1-13.4) and there were 44 deaths (16%) at 2 yr; 26 (9.7%) patients were categorized as Unable to CPET, 69 (25.7%) Unfit and 174 (64.7%) Fit. There were statistically significant differences between the three groups in hospital stay [median (IQR) 14.0 (10.5-23.8) vs 9.9 (5.5-15) vs 7.1 (4.9-10.8) days, P < 0.01] and mortality at 2 yr [11/26 (42%) vs 14/69 (20%) vs 19/174 (11%), respectively (P < 0.01)] although the differences between Unable and Unfit were not statistically different. CONCLUSIONS: Patients' inability to perform CPET is associated with inferior outcomes after major colorectal surgery. Future studies evaluating CPET in risk assessment for major surgery should report outcomes for this subgroup.
Assuntos
Limiar Anaeróbio/fisiologia , Cirurgia Colorretal , Teste de Esforço/métodos , Cuidados Pré-Operatórios/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Indicadores Básicos de Saúde , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco/métodos , Resultado do Tratamento , Adulto JovemRESUMO
The effect of quantum statistics in quantum gases and liquids results in observable collective properties among many-particle systems. One prime example is Bose-Einstein condensation, whose onset in a quantum liquid leads to phenomena such as superfluidity and superconductivity. A Bose-Einstein condensate is generally defined as a macroscopic occupation of a single-particle quantum state, a phenomenon technically referred to as off-diagonal long-range order due to non-vanishing off-diagonal components of the single-particle density matrix. The wavefunction of the condensate is an order parameter whose phase is essential in characterizing the coherence and superfluid phenomena. The long-range spatial coherence leads to the existence of phase-locked multiple condensates in an array of superfluid helium, superconducting Josephson junctions or atomic Bose-Einstein condensates. Under certain circumstances, a quantum phase difference of pi is predicted to develop among weakly coupled Josephson junctions. Such a meta-stable pi-state was discovered in a weak link of superfluid 3He, which is characterized by a 'p-wave' order parameter. The possible existence of such a pi-state in weakly coupled atomic Bose-Einstein condensates has also been proposed, but remains undiscovered. Here we report the observation of spontaneous build-up of in-phase ('zero-state') and antiphase ('pi-state') 'superfluid' states in a solid-state system; an array of exciton-polariton condensates connected by weak periodic potential barriers within a semiconductor microcavity. These in-phase and antiphase states reflect the band structure of the one-dimensional polariton array and the dynamic characteristics of metastable exciton-polariton condensates.
RESUMO
OBJECTIVE: To understand legislation combating counterfeit drugs in Hong Kong. DESIGN: This study consisted of two parts. In part I, counterfeit drugsrelated ordinances and court cases were reviewed. In part II, indepth interviews of the stakeholders were described. SETTING: Hong Kong. PARTICIPANTS: All Hong Kong ordinances were screened manually to identify those combating counterfeit drugs. Court cases were searched for each of the identified cases. Then, the relevant judgement justifications were analysed to identify sentencing issues. Indepth interviews with the stakeholders were conducted to understand their perceptions about such legislation. RESULTS: Trade Marks Ordinance, Patents Ordinance, Trade Descriptions Ordinance, and Pharmacy and Poisons Ordinance were current legislative items combating counterfeit drugs. Sentencing criteria depended on: intention to deceive, quantity of seized drugs, presence of expected therapeutic effect or toxic ingredients, previous criminal records, cooperativeness with Customs officers, honest confessions, pleas of guilty, types of drugs, and precautionary measures to prevent sale of counterfeit drugs. Stakeholders' perceptions were explored with respect to legislation regarding the scale and significance of the counterfeit drug problem, penalties and deterrents, drug-specific legislation and authority, and inspections and enforcement. CONCLUSIONS: To plug the loopholes, a specific law with heavy penalties should be adopted. This could be supplemented by non-legal measures like education of judges, lawyers, and the public; publishing the names of offending pharmacies; and emphasising the role of pharmacists to the public.
Assuntos
Medicamentos Falsificados , Legislação de Medicamentos , Preparações Farmacêuticas/normas , Crime , Hong Kong , Humanos , Assistência Farmacêutica/legislação & jurisprudência , Assistência Farmacêutica/organização & administração , Farmacêuticos/legislação & jurisprudência , Farmacêuticos/organização & administração , Papel ProfissionalRESUMO
Enamel hypoplasia (EH) is a prevalent developmental defect of teeth that can result from various insults, including prenatal nutrient deficiencies. This study aimed to evaluate the association between prenatal serum retinol deficiency and EH in the deciduous teeth of offspring at 2-y of age. A cohort of 1,450 pregnant women was enrolled, and their prenatal nutritional status was assessed between 12 and 14 wk of gestation. Maternal serum retinol, serum 25-hydroxyvitamin D (25OHD), hemoglobin, body mass index, and birth outcomes, infant feeding practices, family socioeconomic status, and demographic information were recorded. Oral health examinations were conducted for the children semiannually, and EH was diagnosed using the Modified DDE index on all the surfaces of erupted teeth. A modified Poisson regression analysis was used to assess the cumulative risk of EH over a period of 2-y. A total of 920 (63.4%) mother-child pairs completed the study, and the cumulative EH prevalence among offspring after 2-y of follow-up was 16.5% (N = 152; 87/1,114 children in the first year and 132/920 in the second year, with 20/920 having EH only in the first year). After adjusting for potential confounders, maternal serum retinol deficiency significantly increased the risk of deciduous EH (risk ratio [RR], 2.0; 95% confidence interval [CI], 1.1-3.7). In addition, deficient serum 25OHD (RR, 6.5; 95% CI, 4.0-10.7), caesarean delivery (RR, 1.6; 95% CI, 1.0-2.4), Muslim (RR, 2.9; 95% CI, 2.0-4.1) and Christian (RR, 2.4; 95% CI, 1.6-3.5) versus Hindu religions, and very preterm birth (RR, 1.7; 95% CI, 1.1-2.9) increased the risk of EH. Children presenting with EH had 2 or more teeth affected, and the maxillary incisors were the most frequently affected, followed by the first primary molars and canines. In conclusion, maternal serum retinol deficiency during the 12 to 14 wk of gestation may increase the risk of deciduous EH, besides the well-established 25OHD deficiency.
Assuntos
Hipoplasia do Esmalte Dentário , Nascimento Prematuro , Deficiência de Vitamina A , Lactente , Humanos , Recém-Nascido , Feminino , Gravidez , Hipoplasia do Esmalte Dentário/epidemiologia , Hipoplasia do Esmalte Dentário/etiologia , Esmalte Dentário , Deficiência de Vitamina A/complicaçõesRESUMO
AIM: Single port laparoscopic colorectal surgery (SPLC), performed through a single incision of ≤ 3 cm, has been shown to be feasible. This study aimed to assess its safety and efficacy when used as the method of choice for right hemicolectomy. METHOD: A prospective study was carried out of patients undergoing right hemicolectomy using a single port laparoscopic technique. They were compared with a historical series of patients undergoing right hemicolectomy using a multiport laparoscopic technique. Between December 2009 and September 2010, single port surgery replaced conventional laparoscopic colorectal surgery (LCS) for radical medial to lateral right hemicolectomy performed by a single surgeon. Histology, length of hospital stay, complications, conversions and readmissions were recorded. RESULTS: Fourteen patients were treated using single port laparoscopic surgery (SPLC): 10 for carcinoma (Dukes A1, B6, C3) and four for Crohn's disease. Twelve patients were treated using multiport laparoscopic colorectal surgery (LCS): eight for carcinoma (Dukes B4, C3, Carcinoid 1), three for Crohn's disease and one for adenoma. The median (interquartile range) operative time for the SPLC group was 120 (90-135) min and for the LCS group was 135 (116-150) min. The median (interquartile range) length of hospital stay was 3.5 (2.0-5.0) days for the SPLC group and for the LCS group was 4.0 (3.8-7.0) days. The median (interquartile range) number of lymph nodes removed for SPLC patients was 14.5 (9.8-19.5) and for the LCS patients was 14.5 (13.0-19.5). There were no conversions, no complications and no readmissions in either group. CONCLUSION: These data confirm the feasibility of the technique. Furthermore they suggest that it is safe and efficacious.
Assuntos
Adenoma/cirurgia , Carcinoma/cirurgia , Colectomia/métodos , Colo Ascendente/cirurgia , Neoplasias Colorretais/cirurgia , Laparoscopia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doença de Crohn/cirurgia , Feminino , Humanos , Tempo de Internação , Ligadura , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos ProspectivosAssuntos
Terapias Complementares/métodos , Estimulação Elétrica/métodos , Equilíbrio Postural , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hong Kong , Humanos , Masculino , Índice de Gravidade de Doença , Método Simples-Cego , Resultado do TratamentoRESUMO
We demonstrate optically induced switching between bright and dark charged divacancy defects in 4H-SiC. Photoluminescence excitation and time-resolved photoluminescence measurements reveal the excitation conditions for such charge conversion. For an energy below 1.3 eV (above 950 nm), the PL is suppressed by more than two orders of magnitude. The PL is recovered in the presence of a higher energy repump laser with a time-averaged intensity less than 0.1% that of the excitation field. Under a repump of 2.33 eV (532 nm), the PL increases rapidly, with a time constant 30 µs. By contrast, when the repump is switched off, the PL decreases first within 100-200 µs, followed by a much slower decay of a few seconds. We attribute these effect to the conversion between two different charge states. Under an excitation at energy levels below 1.3 eV, VSiVC0 are converted into a dark charge state. A repump laser with an energy above 1.3 eV can excite this charged state and recover the bright neutral state. This optically induced charge switching can lead to charge-state fluctuations but can be exploited for long-term data storage or nuclear-spin-based quantum memory.
RESUMO
The objective of this work was to study the chemical and physical characterization of eggshell and eggshell membrane particles prepared from the hen eggshell waste. Under the characterization measurements investigated, it was found that the pore structures of the two biomaterials belong to a typical Type II, indicating that they should be basically characteristic of nonporous materials or materials with macropores or open voids. Further, the chemical composition of the resulting eggshell particle was strongly associated with the presence of carbonate minerals from the Fourier transform infrared (FTIR) spectra. In contrast to the resulting eggshell membrane particle, the presence of functional groups of amines and amides was observable because of its chemical composition of fibrous proteins. From the isotherm data of methylene blue at 25 degrees C, the Freundlich model yielded a somewhat better fit than the Langmuir model. The adsorption isotherms revealed the eggshell biosorbents could only uptake the basic dye of less than 1.0mg/g in aqueous medium, which was attributed to their poor pore properties.
Assuntos
Casca de Ovo/química , Adsorção , Animais , Galinhas , Casca de Ovo/citologia , Casca de Ovo/ultraestrutura , Feminino , Membranas/química , Membranas/citologia , Azul de Metileno , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Dural arteriovenous shunts and pial arteriovenous fistulas are uncommonly associated. Their etiology, pathogenesis, and natural history are still unclear and are likely different. We present three cases of high-flow dural arteriovenous shunts associated with pial arteriovenous fistulas and discuss their pathogenesis, anatomic association, and angioarchitecture. We propose that venous steal effect in the dural sinus secondary to the high-flow dural arteriovenous shunt induced the pial arteriovenous fistulas. Treatment of the high-flow dural arteriovenous shunts and the induced pial arteriovenous fistulas are discussed.
Assuntos
Fístula Arteriovenosa/etiologia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Artérias Cerebrais , Veias Cerebrais , Adulto , Pré-Escolar , Humanos , Lactente , MasculinoRESUMO
The adsorption of basic dye (i.e., ethyl violet or basic violet 4) from aqueous solution onto the regenerated spent bleaching earth (RSBE) was carried out by varying the process parameters such as initial concentration, pH, and temperature. As analytical comparisons, activated bleaching earth (ABE) was also used as adsorbent for the adsorption of the basic dye at various initial concentrations. The experimental results showed that the adsorption process can be well described with the pseudo-second-order reaction model and less fitted by the intra-particle diffusion model. The kinetic parameters of both models obtained in the present work are in line with pore properties of the two adsorbents. According to the equilibrium adsorption capacity from the fitting of pseudo-second-order reaction model, it was further found that the both models of Langmuir and Freundlich appeared to fit well the isotherm data. In addition, the thermodynamic parameters were evaluated based on the pseudo-second-order rate constants, showing that the adsorption of ethyl violet onto the RSBE is endothermic in nature.
Assuntos
Bentonita/química , Corantes de Rosanilina/química , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Modelos Químicos , Soluções/química , Propriedades de Superfície , Temperatura , Água/químicaRESUMO
A patient with an unusual "compulsion" to induce syncope over a period of years by bilateral compression of the carotid arteries subsequently had recurrent seizures. The EEG showed patterns typical of cerebral ischemia during the syncope and epileptogenic foci in both temporal lobes after sleep deprivation. It is difficult to distinguish between seizure and syncope associated with involuntary movements when making a differential diagnosis. We hypothesize that the frequent self-induced ischemic insult to the brain caused a cicatrix to develop, which in turn caused the frequent seizure disorder; and that because this ischemia functioned as a stimulus to the reward site in the limbic system, the patient repeatedly induced it.
Assuntos
Isquemia Encefálica/complicações , Doenças das Artérias Carótidas/complicações , Comportamento Compulsivo , Convulsões/etiologia , Síncope/complicações , Adulto , Isquemia Encefálica/etiologia , Feminino , Humanos , Autoestimulação , Síncope/etiologiaRESUMO
A 28-year-old woman developed complex partial seizures at the age of 17 years and was treated with phenytoin sodium. Five years later she developed myasthenia gravis, and phenytoin was replaced by valproic acid and phenobarbital. She required plasmapheresis (PP). During one course of PP, total and unbound concentrations of valproic acid and phenobarbital were measured in serum sampled before, during, and after PP and in plasma removed by PP. It was determined that the magnitude of loss of valproic acid or phenobarbital by PP was small, and the changes of unbound/total ratio did not reach clinical importance.