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Carbon capture, storage, and utilization have become familiar terms when discussing climate change mitigation actions. Such endeavors demand the availability of smart and inexpensive devices for CO2 monitoring. To date, CO2 detection relies on optical properties and there is a lack of devices based on solid-state gas sensors, which can be miniaturized and easily made compatible with Internet of Things platforms. With this purpose, we present an innovative semiconductor as a functional material for CO2 detection. A nanostructured In2O3 film, functionalized by Na, proves to enhance the surface reactivity of pristine oxide and promote the chemisorption of even rather an inert molecule as CO2. An advanced operando equipment based on surface-sensitive diffuse infrared Fourier transform is used to investigate its improved surface reactivity. The role of sodium is to increase the concentration of active sites such as oxygen vacancies and, in turn, to strengthen CO2 adsorption and reaction at the surface. It results in a change in film conductivity, i.e., in transduction of a concentration of CO2. The films exhibit excellent sensitivity and selectivity to CO2 over an extra-wide range of concentrations (250-5000 ppm), which covers most indoor and outdoor applications due to the marginal influence by environmental humidity.
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This work presents the design and validation of a measuring instrumentation for an easy, complete, and tunable characterization of chemiresistive gas sensors based on metal-oxide semiconductors. The equipment, described in depth both as hardware and as software, was designed to monitor the electrical behavior of gas sensors in controlled thermodynamic conditions. The main goal of this setup is to synchronize the electrical characterization with different measuring conditions, i.e., operating temperature, relative humidity, and gas target concentration. This operation allows us to automate various measurement protocols, otherwise impossible to obtain manually. In particular, this instrumentation permits to correlate the response of a chemiresistive gas sensor to the applied voltage, to its working temperature, and to the gas concentration, automating the acquisition of the current-voltage characteristic and the current-temperature characteristic (Arrhenius plot) of sensing films. The experimental setup was validated by reporting the electrical characterization of a standard metal-oxide-based gas sensing material, such as SnO2, working under different thermodynamic conditions.
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This systematic review of the literature aimed to identify studies examining the psychometric properties of the Jebsen-Taylor Hand Function Test (JTHFT) in various international populations on. The search was conducted in MEDLINE, SCOPUS, CINAHL and Web Of Science, with no restrictions on publication period, the country in which the study was conducted, or the age of the patients. Eligible studies were selected on the basis of inclusion criteria and data were extracted. Study quality and the risk of bias were assessed using the COnsensus-based Standards to select the health Measurement Instruments (COSMIN) checklist. 805 articles were identified; after removing duplicates, there were 361 single studies. 338 articles did not concern the psychometric properties of JTHFT. The remaining 23 studies were selected for full text review, and all were included. They comprised 8 languages and 9 pathologies. These findings suggest the JTHFT is a useful test of manual dexterity in activities of daily living. This study provides specific information on the instrument's psychometric properties in different populations and supports clinicians in making informed decisions when choosing instruments for upper-limb evaluations.
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Atividades Cotidianas , Extremidade Superior , Consenso , Humanos , PsicometriaRESUMO
BACKGROUND: Laparoscopic adrenalectomy is now used worlwide and is a great advance in laparoscopic technology. The reported benefits of this approach include decreased blood loss, better intraoperative haemodynamic control and shorter hospital stay, however some doubts on its indication for adrenal secreting tumors are still present. The aim of this retrospective study is to compare the physiologic alterations on blood pressure during laparoscopic and laparotomic adrenalectomy in patients with adrenal secreting adenoma, the intraoperative blood loss and mean hospital stay in the 2 groups of patients. A review of the literature is included. METHODS: Laparoscopic adrenalectomy was performed in 13 patients (Conn's syndrome with adrenal adenoma in 10, pheochromocytoma in 3). Laparotomy was used for adrenalectomy in 9 patients: 4 with pheochromocytoma and 5 with Conn's adenoma. All the selected patients in the 2 groups had benign adenoma with tumor size less than 6 cm. During surgery the following data were determined: blood pressure before inducing anaesthesia, pressure peaks, episodes of hypertension and of hypotension, blood loss and operating times. The mean hospital stay was also recorded. RESULTS: No differences were found in the blood-pressure values of the 2 groups of patients. The blood loss was minimal in all but 2 patients. The mean hospital stay was significantly longer in those patients who underwent laparotomy. No significant differences were recorded in the mean operating time. CONCLUSIONS: The 2 techniques seem to have the same physiological consequences in the cardiovascular system, and the operating times for laparoscopic and laparotomic adrenalectomy are not so different. Laparoscopic adrenalectomy is a safe technique to treat small benign adrenal secreting adenomas.
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Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Pressão Sanguínea , Laparoscopia , Laparotomia , Feocromocitoma/cirurgia , Adenoma/complicações , Adenoma/metabolismo , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/metabolismo , Adrenalectomia/estatística & dados numéricos , Adulto , Idoso , Aldosterona/metabolismo , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Pressão Sanguínea/efeitos dos fármacos , Epinefrina/metabolismo , Feminino , Humanos , Complicações Intraoperatórias/prevenção & controle , Laparoscopia/estatística & dados numéricos , Laparotomia/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Norepinefrina/metabolismo , Feocromocitoma/complicações , Feocromocitoma/metabolismo , Medicação Pré-Anestésica , Estudos Retrospectivos , Cirurgia Vídeoassistida/estatística & dados numéricosRESUMO
Pheochromocytoma of the adrenal gland can be the cause of massive and lethal retroperitoneal haemorrhage presenting as acute abdomen. Here we report a case of retroperitoneal hematoma, with concomitant peritoneal spillage, due to the spontaneous rupture of a silent pheochromocytoma. The main clinical findings of this disease will be described. Therapy and prognosis will be also discussed.
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Abdome Agudo/etiologia , Neoplasias das Glândulas Suprarrenais/diagnóstico , Hematoma/etiologia , Feocromocitoma/diagnóstico , Espaço Retroperitoneal , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/terapia , Diagnóstico Diferencial , Hematoma/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Feocromocitoma/complicações , Feocromocitoma/terapia , Prognóstico , Ruptura EspontâneaRESUMO
BACKGROUND: The authors reviewed the experience on the use of laparoscopy performed since January 1997 in malignant neoplasms at their institution. The aim of the study was to evaluate the real effectiveness of this procedure in the staging of abdominal neoplasms which were considered resectable at preoperative examinations and in particular in the detection of peritoneal metastases not evidenced with traditional imaging techniques. METHODS: Twenty-eight patients with malignant neoplasms: colo-rectum (15), stomach (5), pancreas (4), gallbladder (2), cardias (1), liver (1), were studied. All the patients were preoperatively examined with abdominal computed tomography (CT). In the 2 patients with gallbladder neoplasm a MR cholangiography was also performed. An explorative laparoscopy with peritoneal washing was then performed in all the patients. The diagnostic and therapeutic choices were subsequently done on the basis of laparoscopy results. RESULTS: Therapeutic approach was modified in 21% of cases, as a result of the detection of peritoneal metastases which were not evidenced with imaging examinations. On the contrary, peritoneal washing was not responsible of any preoperative evaluation. CONCLUSIONS: Laparoscopy performed in patients with abdominal neoplasms allows the detection of peritoneal micrometastases not previously evidenced through preoperative CT, thus modifying the therapeutic approach.
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Laparoscopia , Neoplasias Peritoneais/secundário , Neoplasias Abdominais/diagnóstico , Neoplasias Abdominais/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/cirurgiaRESUMO
BACKGROUND: The more wide spread laparoscopic technique to operate on the adrenal gland is transabdominal approach with a lateral flank adrenalectomy. However, the transabdominal anterior approach can be a sure and safe alternative in selected patients. METHODS: From 1997 to 1999, 18 selected patients underwent laparoscopic anterior adrenalectomy. Mean age was 43 years (range 25-63) with a male/female ratio of 1:1. Indications were Conn's adenoma in 10 patients, pheochromocytoma in 3 cases, Cushing syndrome in 1 and incidentaloma in 4. All the procedures were carried out laparoscopically and only one patient required conversion to an open adrenalectomy for clear signs of malignancy. The mean time for adrenalectomy was 140 minutes and the shorter times were recorded in the right-sided procedures (mean time 84 minute). Estimated blood loss was minimal and no transfusion was done. There were no postoperative complications related to the surgical technique and the hospital stay was 4 days in average. RESULTS: Our data confirm, according with other authors, that this method is feasible in selected patients. Longer times recorded for the left-sided lesions were due to the more difficult dissection required to gain the left adrenal gland. CONCLUSIONS: Transabdominal adrenalectomy with patient in the supine position is feasible, but its use is restricted to the cases with suspect bilateral or multifocal pheochromocytoma, to patients with concomitant abdominal pathologies that can be operated on laparoscopically, to surgeons who prefer to have a frontal view of the operative field.
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Adrenalectomia/métodos , Laparoscopia/métodos , Peritônio/cirurgia , Cirurgia Vídeoassistida/métodos , Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Síndrome de Cushing/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Feocromocitoma/cirurgia , Estudos RetrospectivosRESUMO
AIM: Considering that laparoscopic procedure is associated with increased resistance to lower-limb venous return and subsequent stasis, with possible implications in terms of thromboembolic complications, the aim of our study was to investigate prospectively the coagulative-fibrinolytic profile, in laparoscopic and open cholecystectomy, in patients randomly alloted to receive or not preoperative heparin. METHODS: We prospectively analyzed 36 patients (20 laparoscopic and 16 open) and we randomly divided the patients in two groups: Group-A (28 patients--16 laparoscopic and 12 open) didn't take any preoperative thromboprophylaxis, Group-B (8 patients--4 laparoscopic and 4 open) took preoperative subcutaneous heparin. We took blood venous samples before surgery, at time 0 and + 30 min., at the end and 1 and 24 hours postoperatively. The following parameters were assessed: prothrombin time, partial thromboplastin time, fibrinogen and D-dimer. We statistically analyzed the differences by ANOVA test. RESULTS: In Group A, fibrinogen and D-dimer were significantly higher (p < 0.0001 and p = 0.0266) in open group as compared with laparoscopic one and we observed significant time-depending changes of fibrinogen's concentration (p = 0.0168). In Group B we obtained a higher fibrinogen's value in laparoscopic group than in conventional one, with a significant difference (p = 0.0283); also, the sampling-time affected the result in a very significant meaning (p = 0.0041). Comparing fibrinogen levels between Groups A and B, we observed lower values in heparin-treated group than in the other one (p < 0.0001), while in laparoscopic surgery there was not a significant difference between two groups of treatment. CONCLUSIONS: Our preliminary data suggest that, perioperatively (besides a smaller laparoscopic acute-phase response) the coagulative-fibrinolytic changes are lower in laparoscopic cholecystectomy than in open one and heparin treatment significantly reduces these changes in open surgery but doesn't seem to affect laparoscopic group. Our results seem to show another possible advantage of the laparoscopic surgical procedures over the traditional ones.
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Colecistectomia Laparoscópica , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Colecistectomia Laparoscópica/estatística & dados numéricos , Colelitíase/sangue , Colelitíase/cirurgia , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de TempoRESUMO
Authors performed the mechanical termino-lateral bilio-digestive anastomosis, adopting a circular 21 mm stapler device. The patient was affected by non neoplastic papillary stenosis producing a common biliary tract dilatation so large to allow the stapler's head introduction. A 12 month follow-up was performed using ultrasonography and MRI cholangiopancreatography, that obtained a good demonstration of both biliary tract and bilio-digestive anastomosis.
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Coledocostomia , Grampeadores Cirúrgicos , Ampola Hepatopancreática , Colestase Extra-Hepática/cirurgia , Doenças do Ducto Colédoco/cirurgia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Fatores de TempoRESUMO
After the spleen the liver is the most exposed organ to injury in abdominal blunt trauma. The improvement in imaging techniques and in anesthesia and intensive care have contributed to a fallen in mortality rate and an enhanced possibility in non-operative management. In unstable patients the packing may be used to defer the definitive operation. The Authors report a case of liver injury of two lobes where the packing was followed by liver wrapping with an absorbable mesh. The patient, a female aged 67, resulted to have a bilobar liver injury of IV degree in the injury severity score. The delay of reoperation was 15 days. The procedure was complicated by a subphrenic abscess, successfully managed with non-operative procedures. Wrapping after liver packing may be considered a good option in unstable patient affected, by severe liver injuries after blunt abdominal traumas.
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Embolização Terapêutica/métodos , Hemostasia Cirúrgica/métodos , Fígado/lesões , Traumatismo Múltiplo/cirurgia , Curativos Oclusivos , Ferimentos não Penetrantes/cirurgia , Idoso , Feminino , Humanos , Fígado/cirurgia , Reoperação , Ruptura/cirurgiaRESUMO
Anal fistulas are frequent events which often recur after an inadequate surgical treatment. Nevertheless their evolution into malignant diseases is infrequently observed. The authors report one case of mucinous adenocarcinoma arising out of a recurrent, long-lasting fistula-in-ano. As reported, abdomino-perineal resection combined with radiotherapy can be the choice treatment. The difficulty is to obtain a reliable differential diagnosis. No imaging technique nor histologic examination can establish a definitive reliable diagnosis; nevertheless, as the risk of adenocarcinoma developing from a long-lasting recurrent fistula-in-ano, although small, is real, authors believe that operative exploration and biopsy of recurrent abscesses and fistulas should be recommended.
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Adenocarcinoma/etiologia , Neoplasias do Ânus/etiologia , Fístula Retal/complicações , Adenocarcinoma/cirurgia , Neoplasias do Ânus/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Retal/cirurgia , RecidivaRESUMO
The use of a zirconium compound (ZrOCl(2)) to neutralize HF in the microwave-assisted acid dissolution of ceramic glazes for their chemical analysis was tested. Zr is a strong complexing agent for the fluorine ion and permits the determination of those elements which would form insoluble fluorides. The use of Zr implies strong spectral interferences and a high salt content; however, we found that at least 27 elements can be measured with low detection limits, and satisfactory precision and accuracy. In addition, the use of ZrOCl(2) would permit the complete analysis of a ceramic glaze with a single attack when acid-resistant mineral phases are not present. For potassium determinations in acid matrix, the addition of an ionization buffer was studied in order to increase sensitivity, avoiding ionization interferences and non-linear calibration curves.
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The aim of the present study was to examine the influence of a high carbohydrate diet and the level of aerobic capacity on running performance during a 25-km treadmill time trial. The study used a 2*2 design with the factors being training and diet composition. We divided the athletes in 4 groups: 1. Trained athletes with carbohydrate loading (CHO1); 2. Trained athletes without carbohydrate loading (C1); 3. Untrained athletes with carbohydrate loading (CHO2); 4. Untrained athletes without carbohydrate loading (C2). The carbohydrate loading was effected with confectionery. Performance time, running speed, blood glucose and blood lactate concentrations were evaluated during two 25-km treadmill time trial (trial 1 and trial 2) separated by 7 days in which two groups (CHO1 and CHO2) had a carbohydrate loading. The results showed that the athletes with lower level of aerobic capacity had better performance time after carbohydrate loading. They ran faster and had a higher glucose and lactate concentrations in the last 5 km during trial 2. There were no significant differences in the other groups. In conclusion, we can assert that dietary carbohydrate loading can improve running performance and that confectionery can be used as an effective means of supplementing the normal carbohydrate intake in preparation for endurance competitions. But the improvement depends on some factors such as the distance and the level of aerobic capacity.
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Carboidratos da Dieta/farmacologia , Exercício Físico/fisiologia , Corrida/fisiologia , Adulto , Humanos , Masculino , Estado Nutricional , Aptidão Física/fisiologiaRESUMO
Initiation factor eIF2 binds GTP and promotes the binding of methionyl-tRNA to ribosomes. Biochemical and sequence evidence suggests that the GTP might bind to either the beta- or gamma-subunit of eIF2. Mutations were made in the NKXD consensus elements found in both subunits and individual mutant forms were overexpressed in transiently transfected COS-1 cells. The effect on the translational efficiency of a reporter mRNA for dihydrofolate reductase was monitored. Mutations in the gamma-subunit cause severe repression of protein synthesis, whereas those in the beta-subunit are only mildly inhibitory. The results support the view that GTP binds exclusively to the gamma-subunit.
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Guanosina Trifosfato/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fatores de Iniciação de Peptídeos/genética , Fator de Iniciação 2 em Procariotos , RNA Mensageiro/análise , Tetra-Hidrofolato Desidrogenase/biossínteseRESUMO
Translation initiation factor eIF-4B promotes the binding of mRNA to 40 S preinitiation complexes and together with eIF-4A possesses RNA helicase activity. To elucidate structural features involved in its function, a series of internal and C-terminal deletions, as well as point mutations, were constructed in the eIF-4B cDNA. The mutated cDNAs were expressed in transiently transfected COS-1 cells, and mutant forms of the factor were overproduced up to about 25-fold over endogenous eIF-4B levels. Inhibition of dihydrofolate reductase (DHFR) synthesis by high levels of eIF-4B variants was determined in vivo, and the binding of the eIF-4B forms to biotinylated RNA was measured in vitro. The results indicate that the N-terminal region containing the RNA binding motif with its RNP1 and RNP2 consensus elements is sufficient for inhibition of DHFR synthesis. Deletion of the RNP1 sequence abrogates RNA binding, but amino acid substitutions at conserved residues do not always inhibit RNA binding. Deletion of the DRYG domain near the middle of eIF-4B results in inhibition of RNA binding, but not of DHFR synthesis. Up to 164 residues of the C terminus are not required for RNA binding, but removal of 226 or more residues completely inhibits RNA binding, perhaps by the loss of two arginine-rich regions. The results suggest that both the RNA recognition motif and the arginine-rich region are required for stable RNA binding but that both are not necessary for in vivo inhibition of protein synthesis.
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Fatores de Iniciação em Eucariotos , Fatores de Iniciação de Peptídeos/química , Fatores de Iniciação de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Ribonucleoproteínas/metabolismo , Ribossomos/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Chlorocebus aethiops , Sequência Consenso , Fator de Iniciação 4A em Eucariotos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos , Fatores de Iniciação de Peptídeos/genética , Mutação Puntual , Mapeamento por Restrição , Deleção de Sequência , Tetra-Hidrofolato Desidrogenase/biossíntese , TransfecçãoRESUMO
Levamisole at the concentrations of 240 and 500 micrograms/ml increased DNA-anti-DNA immune complex (IC) binding to thioglycollate-stimulated mouse (CBA) peritoneal macrophages. Reduced IC binding by macrophages of (NZB/NZW)F1 a mouse model for systemic lupus erythematosus occurs as a consequence of disease and was partially corrected after inclusion of levamisole into the reaction mixture in vitro. However, in vivo administration of 2.5 mg/kg of levamisole, the therapeutic dose, did not alter IC binding to CBA macrophages.
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Complexo Antígeno-Anticorpo/metabolismo , Levamisol/farmacologia , Macrófagos/fisiologia , Animais , Lúpus Eritematoso Sistêmico/fisiopatologia , Camundongos , Camundongos Endogâmicos CBA , Camundongos Endogâmicos NZB , Fagocitose/efeitos dos fármacosRESUMO
In order to investigate the role of prolactin in the control of the circadian rhythm of plasma aldosterone (PA), plasma renin activity (PRA), cortisol (PC), aldosterone and prolactin (PRL) levels were determined in samples at 4-hour intervals from 5 normal supine men over a period of 24 h under basal conditions and subsequently over a period of 24 h during suppression of prolactin release by bromocriptine (CB-154). After suppression of prolactin, statistically signific1nt circadian rhythms in PC and PA have been detected with a moderate decrease of PA concentration, while the PC level remained unalterated. PRA rhythmicity persisted with a significant shift of acrophase and remarkable reduction of plasma levels. Moreover, during CB administration a significant correlation was obtained between PA and PC, while no correlation was detected between PA and PRA. These data are consistent with the following concepts: (a) the prolactin does not play a significant role in the regulation of circadian rhythm and concentration of plasma aldosterone in normal supine men, and (b) bromocriptine induces a remarkable reduction of PRA and a variable decrease in plasma aldosterone, but it does not influence the secretion of cortisol in normal subjects.
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Aldosterona/sangue , Bromocriptina/farmacologia , Ritmo Circadiano/efeitos dos fármacos , Hormônio Adrenocorticotrópico/fisiologia , Adulto , Humanos , Hidrocortisona/sangue , Masculino , Postura , Prolactina/sangue , Renina/sangueRESUMO
A study of circadian variations of plasma renin activity in normal supine man.--The cosinor analysis has detected circadian rhythm of PRA in fifteen normal supine men, aged 21-28, studied over a 24-hour span. The acrophase occurs at 05.55 and it is consistent with the findings of the other authors.