Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 102
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-27477826

RESUMO

BACKGROUND: Criteria for transient lower esophageal sphincter relaxations (TLESRs) are well-defined for Dentsleeve manometry. As high-resolution manometry (HRM) is now the gold standard to assess esophageal motility, our aim was to propose a consensus definition of TLESRs using HRM. METHODS: Postprandial esophageal HRM combined with impedance was performed in 10 patients with gastroesophageal reflux disease. Transient lower esophageal sphincter relaxations identification was performed by 17 experts using a Delphi process. Four investigators then characterized TLESR candidates that achieved 100% agreement (TLESR events) and those that achieved less than 25% agreement (non-events) after the third round. Logistic regression and decision tree analysis were used to define optimal diagnostic criteria. KEY RESULTS: All diagnostic criteria were more frequently encountered in the 57 TLESR events than in the 52 non-events. Crural diaphragm (CD) inhibition and LES relaxation duration >10 seconds had the highest predictive value to identify TLESR. Based on decision tree analysis, reflux on impedance, esophageal shortening, common cavity, upper esophageal sphincter relaxation without swallow and secondary peristalsis were alternate diagnostic criteria. CONCLUSION & INFERENCES: Using HRM, TLESR might be defined as LES relaxation occurring in absence of swallowing, lasting more than 10 seconds and associated with CD inhibition.


Assuntos
Deglutição/fisiologia , Esfíncter Esofágico Inferior/fisiologia , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/fisiopatologia , Manometria/normas , Relaxamento Muscular/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
2.
Artigo em Inglês | MEDLINE | ID: mdl-27511606

RESUMO

BACKGROUND: The mechanism of esophageal pain in patients with nutcracker esophagus (NE) and other esophageal motor disorders is not known. Our recent study shows that baseline esophageal mucosal perfusion, measured by laser Doppler perfusion monitoring, is lower in NE patients compared to controls. The goal of our current study was to perform a more detailed analysis of esophageal mucosal blood perfusion (EMBP) waveform of NE patients and controls to determine the optimal EMBP biomarkers that combined with suitable statistical learning models produce robust discrimination between the two groups. METHODS: Laser Doppler recordings of 10 normal subjects (mean age 43 ± 15 years, 8 males) and 10 patients (mean age 47 ± 5.5 years., 8 males) with NE were analyzed. Time and frequency domain features were extracted from the first twenty-minute recordings of the EMBP waveforms, statistically ranked according to four independent evaluation criterions, and analyzed using two statistical learning models, namely, logistic regression (LR) and support vector machines (SVM). KEY RESULTS: The top three ranked predictors between the two groups were the 0.5 and 0.75 perfusion quantile values followed by the surface of the EMBP power spectrum in the frequency domain. ROC curve ranking produced a cross-validated AUC (area under the curve) of 0.93 for SVM and 0.90 for LR. CONCLUSIONS & INFERENCES: We show that as a group NE patients have lower perfusion values compared to controls, however, there is an overlap between the two groups, suggesting that not all NE patients suffer from low mucosal perfusion levels.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Transtornos da Motilidade Esofágica/diagnóstico , Transtornos da Motilidade Esofágica/fisiopatologia , Mucosa Esofágica/irrigação sanguínea , Mucosa Esofágica/fisiologia , Adulto , Esôfago/irrigação sanguínea , Esôfago/fisiologia , Feminino , Humanos , Fluxometria por Laser-Doppler/métodos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Fatores de Tempo
3.
Neurogastroenterol Motil ; 27(7): 971-80, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25930157

RESUMO

BACKGROUND: Multichannel intraluminal impedance (MII) is currently used to monitor gastroesophageal reflux and esophageal bolus clearance. We describe a novel methodology to measure maximal luminal cross-sectional area (CSA) during bolus transport from MII measurements. METHODS: Studies were conducted in-vitro (test tubes) and in-vivo (healthy subjects). Concurrent MII, high resolution manometry, and intraluminal ultrasound (US) images were recorded 7-cm above the lower esophageal sphincter. Swallows with two concentrations of saline, 0.1 and 0.5 N, of bolus volumes 5, 10, and 15 cc were performed. The CSA was estimated by solving two algebraic Ohm's law equations, resulting from the two saline solutions. The CSA calculated from impedance method was compared with the CSA measured from the intraluminal US images. KEY RESULTS: The CSA measured in duplicate from B-mode US images showed a mean difference between the two manual delineations to be near zero, and the repeatability coefficient was within 7.7% of the mean of the two CSA measurements. The calculated CSA from the impedance measurements strongly correlated with the US measured CSA (R(2) ≅ 0.98). A detailed statistical analysis of the impedance and US measured CSA data indicated that the 95% limits of agreement between the two methods ranged from -9.1 to 13 mm(2) . The root mean square error of the two measurements was 4.8% of the mean US-measured CSA. CONCLUSIONS & INFERENCES: We describe a novel methodology to measure peak esophageal luminal CSA from the nadir impedance during peristalsis. Further studies are needed to determine if it is possible to measure patterns of luminal distension during peristalsis across the entire length of the esophagus from the MII recordings.


Assuntos
Deglutição/fisiologia , Esôfago/fisiologia , Peristaltismo/fisiologia , Adulto , Impedância Elétrica , Refluxo Gastroesofágico/fisiopatologia , Humanos , Manometria/métodos , Pessoa de Meia-Idade
4.
Neurogastroenterol Motil ; 26(8): 1122-30, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24861157

RESUMO

BACKGROUND: Esophageal multiple intraluminal impedance (MII) measurement has been used to detect gastro-esophageal reflux and bolus transport. It is not clear if MII can detect changes in luminal cross sectional area (CSA) during bolus transport. Intraluminal ultrasound (US) images, MII, and high resolution manometry (HRM) were recorded simultaneously to determine temporal relationship between CSA and impedance during esophageal bolus transport and to define the relationship between peak distension and nadir impedance. METHODS: Studies were conducted in five healthy subjects. MII, HRM, and US images were recorded 6 cm above LES. Esophageal distensions were studied during swallows and injections of 0.5 N saline bolus into the esophagus. KEY RESULTS: Temporal change in esophageal CSA correlates with changes in impedance (r-value: mean ± SD = -0.80 ± 0.08, range: -0.94 to -0.66). Drop in impedance during distension occurs as a two-step process; initial large drop associated with onset of CSA increase, followed by a small drop during which majority of the CSA increase occurs. Peak CSA and nadir impedance occur within 1 s of each other. Increase in swallow and injection volumes increased the CSA, had no effect on large drop but increased the small drop amplitude. We observed a significant correlation between peak CSA and nadir impedance (r = -0.90, p < 0.001) and a better correlation between peak CSA and inverse impedance (r = 0.94, p < 0.001). CONCLUSIONS & INFERENCES: Further studies are needed to confirm that intraluminal impedance recordings may be used to measure luminal CSA during esophageal bolus transport.


Assuntos
Deglutição/fisiologia , Impedância Elétrica , Esôfago/fisiologia , Peristaltismo/fisiologia , Adulto , Feminino , Humanos , Masculino
5.
Mymensingh Med J ; 23(2): 361-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24858167

RESUMO

To estimate liver function tests in patients with alcoholic fatty liver disease, alcoholic hepatitis and alcoholic cirrhosis and to compare the levels of enzymes between the groups. A hospital based case control study was carried out at Nepalgunj Medical College, Nepal from January 2013 to June 2013. A total of 150 alcoholic associated liver disorders patients aged between 20-70 years and 50 sex age matched normal healthy controls were taken to assess liver function tests (LFTs) by measuring Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatase (ALP), Gamma glutamyltranspeptidase (GGT) & Albumin. The mean±SD of liver function tests (LFTs) of patients of alcoholic fatty liver disease is highest followed by alcoholic hepatitis patients. All the 3 groups of alcoholic associated liver disorders patients when compared to normal healthy control subjects showed statistically significant increase in the levels of AST (p<0.000), ALT (p<0.000), ALP (p<0.006), GGT (p<0.000), & Albumin (p<0.000). Liver function tests values for alcoholic associated liver disorders patients when compared to the healthy control subjects was significantly altered.


Assuntos
Hepatopatias Alcoólicas/diagnóstico , Hepatopatias Alcoólicas/epidemiologia , Adulto , Fatores Etários , Idoso , Estudos de Casos e Controles , Ensaios Enzimáticos Clínicos , Feminino , Humanos , Testes de Função Hepática/métodos , Masculino , Pessoa de Meia-Idade , Nepal , Fatores Sexuais , Adulto Jovem
6.
Neurogastroenterol Motil ; 24(1): 40-6, e2, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22074595

RESUMO

BACKGROUND: Lower esophageal sphincter (LES) lift seen on high-resolution manometry (HRM) is a possible surrogate marker of the longitudinal muscle contraction of the esophagus. Recent studies suggest that longitudinal muscle contraction of the esophagus induces LES relaxation. AIM: Our goal was to determine: (i) the feasibility of prolonged ambulatory HRM and (ii) to detect LES lift with LES relaxation using ambulatory HRM color isobaric contour plots. METHODS: In vitro validation studies were performed to determine the accuracy of HRM technique in detecting axial movement of the LES. Eight healthy normal volunteers were studied using a custom designed HRM catheter and a 16 channel data recorder, in the ambulatory setting of subject's home environment. Color HRM plots were analyzed to determine the LES lift during swallow-induced LES relaxation as well as during complete and incomplete transient LES relaxations (TLESR). KEY RESULTS: Satisfactory recordings were obtained for 16 h in all subjects. LES lift was small (2 mm) in association with swallow-induced LES relaxation. LES lift could not be measured during complete TLESR as the LES is not identified on the HRM color isobaric contour plot once it is fully relaxed. On the other hand, LES lift, mean 8.4 ± 0.6 mm, range: 4-18 mm was seen with incomplete TLESRs (n = 80). CONCLUSIONS & INFERENCES: Our study demonstrates the feasibility of prolonged ambulatory HRM recordings. Similar to a complete TLESR, longitudinal muscle contraction of the distal esophagus occurs during incomplete TLESRs, which can be detected by the HRM. Using prolonged ambulatory HRM, future studies may investigate the temporal correlation between abnormal longitudinal muscle contraction and esophageal symptoms.


Assuntos
Esfíncter Esofágico Inferior/fisiologia , Manometria/métodos , Monitorização Ambulatorial/métodos , Contração Muscular/fisiologia , Relaxamento Muscular/fisiologia , Adulto , Humanos , Manometria/instrumentação , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Adulto Jovem
7.
Kathmandu Univ Med J (KUMJ) ; 10(39): 44-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23434961

RESUMO

BACKGROUND: Type-2 diabetes mellitus is an independent risk factor for coronary artery disease and risk of coronary disease is three to four fold increased in patients with diabetes compared with non-diabetic population and 60-80% 0f type-2 diabetics are obese. METHODS: This study was conducted in Nepalgunj Teaching Hospital, Kohalpur, Banke, Nepal, between 1st March, 2011 and 28th February, 2012. A total of 150 samples were taken to assess the lipid profile in type-2 diabetic patients associated with obesity and 25 obese controls for their lipid profile. Venous blood samples were taken from all the subjects in the morning after fasting overnight. Exclusion criteria included pregnancy, chronic infectious disease, heart failure; renal failure and drug allergy were confirmed from the subject's personal physician report and a detailed history. The data was analyzed using Excel 2003, R 2.8.0 Statistical Package for the Social Sciences (SPSS) for Windows Version 16.0 (SPSS Inc; Chicago, IL, USA) and the EPI Info 3.5.1 Windows Version. RESULTS: The mean ± SD age of diabetic patients with obesity was 53.76± 6.23 while the mean ± SD age of control was 49.61 ± 4.8. Out of 150 patients 105 (70%) were males and 45 (30%) were females. Among control subjects 16 (64%) were males and 9 (36%) were females. Obese type-2 diabetic patients when compared to obese control subjects showed statistically significant increase in the levels of serum total cholesterol (p < 0.001), serum triglycerides (p < 0.001), serum LDL-cholesterol (p < 0.001) while serum HDL-cholesterol levels did not show statistically significant difference in the two group (p > 0.05). CONCLUSION: This study showed obese diabetic individuals have dyslipidemia and more prone to develop cardiovascular diseases.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Dislipidemias/sangue , Lipídeos/sangue , Obesidade/sangue , Adulto , Idoso , Diabetes Mellitus Tipo 2/complicações , Dislipidemias/complicações , Dislipidemias/epidemiologia , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Nepal , Obesidade/complicações , Fatores de Risco
8.
Neurogastroenterol Motil ; 23(11): 1013-9, e460, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21951657

RESUMO

BACKGROUND: Anal sphincter complex consists of anatomically overlapping internal anal sphincter (IAS), external anal sphincter (EAS) and puborectalis muscle (PRM). We determined the functional morphology of anal sphincter muscles using high definition anal manometery (HDAM), three dimensional (3D)-ultrasound (US) and Magnetic resonance (MR) imaging. METHODS: We studied 15 nulliparous women. High definition anal manometery probe equipped with 256 pressure transducers was used to measure the anal canal pressures at rest and squeeze. Lengths of IAS, PRM, and EAS were determined from the 3D-US images and superimposed on the HDAM plots. Movements of anorectal angle with squeeze were determined from the dynamic MR images. KEY RESULTS: High definition anal manometery plots reveal that anal canal pressures are highly asymmetric in the axial and circumferential direction. Anal canal length determined by the 3D-US images is slightly smaller than that measured by HDAM. The EAS (1.9 ± 0.5 cm long) and PRM (1.7 ± 0.4 cm long) surround distal and proximal parts of the anal canal, respectively. With voluntary contraction, anal canal pressures increase in the proximal (PRM) and distal (EAS zone) parts of anal canal. Posterior peak pressure in the anal canal moves cranially in relation to the anterior peak pressure, with squeeze. Similar to the movement of peak posterior pressure, MR images show cranial movement of anorectal angle with squeeze. CONCLUSIONS & INFERENCES: Our study proves that the PRM is responsible for the closure of the cranial part of anal canal. HDAM, in addition to measuring constrictor function can also record the elevator function of levator ani/pelvic floor muscles.


Assuntos
Canal Anal/anatomia & histologia , Canal Anal/diagnóstico por imagem , Canal Anal/fisiologia , Imageamento Tridimensional/métodos , Manometria/métodos , Contração Muscular/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Diafragma da Pelve/anatomia & histologia , Diafragma da Pelve/diagnóstico por imagem , Pressão , Ultrassonografia , Adulto Jovem
9.
Neurogastroenterol Motil ; 23(7): 643-e258, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21418426

RESUMO

BACKGROUND: The length at which a muscle/sarcomere operates in vivo (operational length) and the length at which it generates maximal stress (optimal length) can be quite different. In a previous study, we found that the rabbit external anal sphincter (EAS) operates on the ascending limb of the length-tension curve, in other words at lengths shorter than its optimal length (short sarcomere length). In this study, we tested whether the human EAS muscle also operates at a short sarcomere length. METHODS: The length-tension relationship of the EAS muscle was studied in vivo in 10 healthy nullipara women. EAS muscle length was altered by anal distension using custom-designed probes of 5, 10, 15, and 20mm diameter. Probes were equipped with a sleeve sensor to measure anal canal pressure. The EAS muscle electromyograph (EMG) was recorded using wire electrodes. Ultrasound images of anal canal were obtained to measure EAS muscle thickness and anal canal diameter. EAS muscle stress was calculated from the anal canal pressure, inner radius, and thickness of the EAS muscle. KEY RESULTS: Rest and squeeze stress of the anal canal increased with the increase in probe size. Similarly, the change in anal canal stress, i.e. the difference between the rest and the squeeze, which represents the active contribution of EAS to the anal canal stress, increased with the increase in probe size. However, increase in probe size was not associated with an increase in the external anal sphincter EMG activity. CONCLUSIONS & INFERENCES: Increase in EAS muscle stress with the increase in probe size, in the presence of constant EMG (neural input), demonstrates that the human EAS muscle operates on the ascending limb of the length-tension curve or at low sarcomere lengths. We propose that surgically adjusting EAS sarcomere length may represent a novel strategy to treat fecal incontinence in humans.


Assuntos
Canal Anal/patologia , Canal Anal/fisiologia , Sarcômeros/patologia , Sarcômeros/fisiologia , Adulto , Canal Anal/diagnóstico por imagem , Eletrodos , Eletromiografia , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Manometria , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Sarcômeros/diagnóstico por imagem , Ultrassonografia
10.
Neurogastroenterol Motil ; 23(3): 201-7, e110, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21083789

RESUMO

BACKGROUND: Current understanding is that swallow induces simultaneous inhibition of the entire esophagus followed by a sequential wave of contraction (peristalsis). We observed a pattern of luminal distension preceding contraction which suggested that inhibition may also traverses in a peristaltic fashion. Our aim is to determine the relationship between contraction and luminal distension during bolus transport. METHODS: Eight subjects using two solid-state pressure and two ultrasound (US) transducers were studied. Synchronous pressure and US images were obtained with wet swallows and after edrophonium and atropine. Luminal cross-sectional area (CSA) at 2 cm and 12 cm above the lower esophageal sphincter (LES) were recorded. Relationship between pressure and CSA at each site, propagation velocity of peak pressure and peak distension waves were determined. Fluoroscopy coupled with manometry was also performed in five normal subjects. KEY RESULTS: Esophageal distension precedes contraction wave at both-recorded sites. During distension, esophageal pressure remains constant while luminal CSA increases significantly. The onset and the peak of distension wave traverses in a peristaltic fashion between both sites. A tight coupling exists between the peak distension and peak contraction waves with similar velocities (3.7 cm s(-1) and 3.6 cm s(-1)) of propagation. The degree of distension is greater at 2 cm compared to 12 cm. Atropine and edrophonium reduced and increased the contraction pressure respectively, without affecting the distension wave. Fluoroscopic study confirmed that the wave of distension traverses the esophagus in a peristaltic fashion. CONCLUSIONS & INFERENCES: Distension and contraction waves are tightly coupled to each other and both traverse in a peristaltic fashion.


Assuntos
Deglutição/fisiologia , Esôfago/anatomia & histologia , Esôfago/fisiologia , Contração Muscular/fisiologia , Peristaltismo/fisiologia , Adulto , Esôfago/diagnóstico por imagem , Feminino , Fluoroscopia , Humanos , Masculino , Manometria/instrumentação , Manometria/métodos , Pressão , Transdutores , Ultrassonografia
11.
Neurogastroenterol Motil ; 23(1): 45-51, e3, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20939848

RESUMO

BACKGROUND: Factors that determine the spread of gastro-esophageal reflux (GER) along the length of the esophagus are not known. We investigated if cardiovascular (CV) compressions on the esophagus may determine the spread of refluxate into the proximal esophagus. METHODS: High-resolution manometry (HRM) and multi-channel intra-luminal impedance recording (MIIR) were performed simultaneously in 10 normal subjects in the recumbent and upright positions. Pulsatile pressure increases on the esophagus (marker of CV compression) were identified on the HRM. Spread of refluxate into the esophagus was determined by the MIIR. KEY RESULTS: Cardiovascular compression zones were observed in the esophagus in 9 out of 10 subjects in recumbent position. Forty percent of GER episodes were limited to the distal esophagus in the recumbent position and CV compression pressure was greater than distal esophageal pressure at the time of GER in all such cases. On the other hand, distal esophageal pressure was greater than CV compression pressure when the refluxate extended into the proximal esophagus. In the upright position, CV compression was less frequent than recumbent position and only 12% of GER episodes were limited to the distal esophagus. CONCLUSIONS & INFERENCES: Cardiovascular compression of the esophagus is frequently observed in normal healthy subject and restricts the spread of refluxate into the proximal esophagus.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Esôfago/anatomia & histologia , Refluxo Gastroesofágico/fisiopatologia , Pressão , Adulto , Impedância Elétrica , Esôfago/fisiologia , Humanos , Masculino , Manometria/métodos , Postura , Adulto Jovem
12.
Neurogastroenterol Motil ; 23(1): 70-5, e7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20939857

RESUMO

BACKGROUND: Our recent studies show that the external anal sphincter muscle (EAS) operates at a sarcomere length range which is below optimal. In this study, we tested the hypothesis that by surgically increasing sarcomere length and bringing it close to the optimal length, EAS muscle function and anal canal pressure can be enhanced. METHODS: Rabbits (n = 25) were anesthetized and subjected to either a sham or an EAS plication of different length by placing sutures at two locations, at a distance of 13%, 20%, 28%, or 35% of the circumferential length of the anal canal. Anal canal pressures were recorded before and after the plication. Anal canal was harvested and the EAS muscle sarcomere length was measured using laser diffraction. KEY RESULTS: Electrical stimulation of the EAS muscle resulted in a stimulus-dependent increase in the anal canal pressure (mmHg) and EAS muscle stress (mN mm(-2)). A significant increase in maximal pressure (212 ± 13 after compared with 139 ± 22 before plication) as well as stress (166 ± 10 after as compared with 88 ± 14 before plication) was recorded at 20% plication length. Passive anal canal stress at 20% plication was not significantly different compared with the sham group. The mean sarcomere lengths with sham and 20% plication were 2.11 and 2.60 µm, respectively. CONCLUSIONS & INFERENCES: EAS plication resulted in a length-dependent increase in EAS muscle sarcomere length with an optimal sarcomere length at 20% plication. These considerations may help guide repair of anal sphincter muscle defects in the humans.


Assuntos
Canal Anal/anatomia & histologia , Canal Anal/fisiologia , Músculo Liso/anatomia & histologia , Sarcômeros/ultraestrutura , Canal Anal/cirurgia , Animais , Estimulação Elétrica , Humanos , Contração Muscular/fisiologia , Coelhos , Sarcômeros/fisiologia
13.
Waste Manag ; 30(11): 2265-77, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20688504

RESUMO

The objective of this paper is to estimate the future projection of computer waste in India and to subsequently analyze their flow at the end of their useful phase. For this purpose, the study utilizes the logistic model-based approach proposed by Yang and Williams to forecast future trends in computer waste. The model estimates future projection of computer penetration rate utilizing their first lifespan distribution and historical sales data. A bounding analysis on the future carrying capacity was simulated using the three parameter logistic curve. The observed obsolete generation quantities from the extrapolated penetration rates are then used to model the disposal phase. The results of the bounding analysis indicate that in the year 2020, around 41-152 million units of computers will become obsolete. The obsolete computer generation quantities are then used to estimate the End-of-Life outflows by utilizing a time-series multiple lifespan model. Even a conservative estimate of the future recycling capacity of PCs will reach upwards of 30 million units during 2025. Apparently, more than 150 million units could be potentially recycled in the upper bound case. However, considering significant future investment in the e-waste recycling sector from all stakeholders in India, we propose a logistic growth in the recycling rate and estimate the requirement of recycling capacity between 60 and 400 million units for the lower and upper bound case during 2025. Finally, we compare the future obsolete PC generation amount of the US and India.


Assuntos
Computadores , Eliminação de Resíduos/métodos , Adolescente , Adulto , Eletrônica , Monitoramento Ambiental , Previsões , Humanos , Índia , Modelos Logísticos , Pessoa de Meia-Idade , Modelos Estatísticos , Dinâmica Populacional , Reciclagem , Fatores de Tempo
14.
Waste Manag ; 30(3): 483-91, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19857950

RESUMO

The purpose of this study is to construct an approach and a methodology to estimate the future outflows of electronic waste (e-waste) in India. Consequently, the study utilizes a time-series multiple lifespan end-of-life model proposed by Peralta and Fontanos for estimating the current and future quantities of e-waste in India. The model estimates future e-waste generation quantities by modeling their usage and disposal. The present work considers two scenarios for the approximation of e-waste generation based on user preferences to store or to recycle the e-waste. This model will help formal recyclers in India to make strategic decisions in planning for appropriate recycling infrastructure and institutional capacity building. Also an extension of the model proposed by Peralta and Fontanos is developed with the objective of helping decision makers to conduct WEEE estimates under a variety of assumptions to suit their region of study. During 2007-2011, the total WEEE estimates will be around 2.5 million metric tons which include waste from personal computers (PC), television, refrigerators and washing machines. During the said period, the waste from PC will account for 30% of total units of WEEE generated.


Assuntos
Computadores , Resíduos Perigosos , Algoritmos , Terminais de Computador , Conservação dos Recursos Naturais , Eletrônica , Índia , Resíduos Industriais , Manufaturas , Microcomputadores , Modelos Teóricos , Papel , Eliminação de Resíduos/métodos , Software
15.
Gut ; 58(8): 1056-62, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19136515

RESUMO

BACKGROUND: Oesophageal motility, as measured by manometry, is normal in the majority of patients with eosinophilic oesophagitis (EO). However, manometry measures only the circular muscle function of the oesophagus. The goal of the present study was to assess circular and longitudinal muscle function during peristalsis in patients with EO. METHODS: Ultrasound imaging and manometry were simultaneously acquired during swallow-induced peristalsis in patients with EO and controls to measure the longitudinal muscle and circular muscle contraction, respectively. A probe with an ultrasound transducer was positioned 2 cm and then 10 cm above the lower oesophageal sphincter and five, 5 ml water swallows were recorded before and after edrophonium. RESULTS: There is no difference in the incidence of swallow-induced peristalsis and manometric pressures (a marker of circular muscle contraction) between controls and patients with EO. However, changes in the muscle thickness (a marker of longitudinal muscle contraction) are markedly diminished in patients with EO, at both 2 and 10 cm above the lower oesophageal sphincter. The longitudinal muscle response to edrophonium is markedly blunted in patients with EO. Normal subjects demonstrate synchrony between the circular and longitudinal muscle contraction during peristalsis that is affected by edrophonium. On the other hand, patients with EO demonstrate mild asynchrony of circular and longitudinal muscle contraction during swallow-induced contractions that is not altered by edrophonium. CONCLUSIONS: In patients with EO, there is selective dysfunction of the longitudinal muscle contraction during peristalsis. It is proposed that the longitudinal muscle dysfunction in EO may contribute to dysphagia.


Assuntos
Eosinofilia/fisiopatologia , Esofagite/fisiopatologia , Esôfago/fisiopatologia , Músculo Liso/fisiopatologia , Adulto , Inibidores da Colinesterase/farmacologia , Edrofônio/farmacologia , Eosinofilia/diagnóstico por imagem , Esofagite/diagnóstico por imagem , Esofagite/patologia , Esôfago/diagnóstico por imagem , Feminino , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/diagnóstico por imagem , Músculo Liso/patologia , Ultrassonografia , Adulto Jovem
16.
Aliment Pharmacol Ther ; 29(8): 863-70, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19170660

RESUMO

BACKGROUND: Proton pump inhibitor (PPI) therapy is known to suppress gastric acid secretion. Thus PPI therapy may decrease gastric volume and gastric contents available for gastro-oesophageal reflux by decreasing acid secretion. AIM: To determine the effect of PPI therapy on the gastric volume after a standard meal. METHODS: A total of nine healthy subjects were studied using magnetic resonance imaging, before and after a standard liquid meal mixed with a paramagnetic contrast to help demarcate the gastric region. Images were acquired for a total of 90 min after the meal. Studies were conducted before and following esomeprazole twice daily for 7 days. Images were analysed to determine the gastric liquid volume. RESULTS: Gastric volume, 15 min after the meal peaked to 611 +/- 37 mL on the control day and 539 +/- 30 mL following the PPI administration (P < 0.001). Average gastric volume remained significantly lower (56 +/- 9 mL, P < 0.05) on the PPI therapy from 5 to 75 min after the meal. CONCLUSIONS: Proton pump inhibitor therapy causes a significant reduction in the gastric contents volume during first 75 min after the meal. In addition to increasing the gastric pH, PPI therapy may decrease the frequency of gastro-oesophageal reflux by decreasing the volume of gastric contents.


Assuntos
Esomeprazol/farmacologia , Inibidores da Bomba de Prótons/farmacologia , Estômago/efeitos dos fármacos , Adulto , Esomeprazol/uso terapêutico , Feminino , Refluxo Gastroesofágico/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Variações Dependentes do Observador , Inibidores da Bomba de Prótons/administração & dosagem
17.
J Environ Biol ; 28(2): 265-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17915762

RESUMO

Correlation coefficient analysis conducted on 22 triticale x bread wheat derivatives along with six checks to select true- breeding derivative(s) for future hybridization programme with tolerance to drought and cold stress conditions as well as better quality traits revealed significant correlation of grain yield with spikelets per spike, biological yield, harvest index, leaf area index. Interestingly, the grain yield and drought susceptibility index showed no association. However, with cold tolerance it showed significant positive correlation indicating the desirability of certain plant traits under cold stress. The grain yield exhibited no association with quality traits which might assist in the predictability of high yielding varieties with high protein, total sugars, reducing sugars and non-reducing sugars. Path coefficient analysis revealed that biological yield had the highest positive direct effect on grain yield followed by harvest index, specific leaf weight, stomatal number, 1000 grain weight, stomatal size, spikelets per spike and days to heading. Therefore, indirect selection for these plant traits in order should be exercised in selecting drought tolerant genotypes. Two genotypes (RL-124-2P2 and RL 111P2) were found to be drought and cold tolerant with high grain yield, spikes per plant, spikelets per spike and leaf area index.


Assuntos
Temperatura Baixa , Desastres , Triticum/fisiologia , Adaptação Biológica , Pão , Metabolismo dos Carboidratos , Genótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Estômatos de Plantas/anatomia & histologia , Triticum/anatomia & histologia
18.
Ultrasound Obstet Gynecol ; 30(2): 201-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17605148

RESUMO

OBJECTIVES: To evaluate whether transperineal three-dimensional (3D) ultrasound can be used to depict normal anal sphincter anatomy and to measure the thickness of muscle layers and the anteroposterior length of the levator hiatus. METHODS: The study included 22 normal nulliparous female volunteers. Transperineal 3D sonographic evaluation of the anal canal included assessment of sphincter shape, echogenicity, marginal definition and muscle thickness. Measurements of the thickness of the internal anal sphincter (IAS) and puborectalis muscle (PRM) were determined with the women at rest and during squeezing by two observers, and interobserver reliability was determined. The anteroposterior length of the levator hiatus at rest and during squeezing was measured. RESULTS: The proximal end of the anal canal (towards the rectum) consisted of overlapping IAS and PRM, and the distal end (towards the anus) consisted of overlapping IAS and external anal sphincter (EAS). At the PRM level, the mean +/- SD IAS thickness was 2.3 +/- 0.5 mm at rest and 2.5 +/- 0.4 mm during squeezing, and at the mid-EAS level it was 2.9 +/- 0.5 mm at rest and 2.8 +/- 0.5 mm during squeezing. The PRM thickness was 6.5 +/- 1.0 mm at rest and 6.4 +/- 1.2 mm during squeezing. The difference in muscle thickness of the sphincter layers with the woman at rest and during squeezing was not significant. The anteroposterior length of the levator hiatus was 51.7 +/- 5.0 mm at rest and 47.4 +/- 4.1 mm during squeezing (P < 0.01). CONCLUSION: Transperineal 3D ultrasound may be useful in evaluating the anatomy of the anal canal.


Assuntos
Canal Anal/diagnóstico por imagem , Endossonografia/métodos , Imageamento Tridimensional , Músculo Esquelético/diagnóstico por imagem , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
20.
Neurogastroenterol Motil ; 18(5): 376-84, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16629865

RESUMO

Relaxation and opening of the oesophago-gastric junction (OGJ) is crucial for oesophageal transport. A novel ultrasound technique was used to determine OGJ opening, before and after atropine, in 12 normals. An ultrasound probe, a solid-state pressure transducer and an infusion tube were placed inside a 20-mm diameter bag, which was placed across the OGJ. At various bag pressures ultrasound transducer was pulled across the bag. Acquired B-mode ultrasound images were converted into M-mode image to display the oesophagus, OGJ and stomach. At low bag-pressure (< 20 mmHg), the OGJ but not oesophagus and stomach, is collapsed around the bag. Increasing bag pressure results in gradual opening of the OGJ from distal end. M-mode image identified the narrowest region of OGJ and corresponding cross-sectional area (CSA) was measured. Mean bag pressure to initial OGJ opening was 18 mmHg. Linear relationship between bag-pressure and OGJ-CSA was observed. Atropine reduced opening bag pressure and shifted the OGJ pressure-CSA curve upward without altering slope, i.e. compliance. Our novel ultrasound technique to study the OGJ opening function shows two distinct components; firstly, related to the tonic OGJ contraction and secondly, to passive or viscoelastic properties of the OGJ.


Assuntos
Atropina/farmacologia , Endossonografia/métodos , Junção Esofagogástrica/efeitos dos fármacos , Junção Esofagogástrica/diagnóstico por imagem , Junção Esofagogástrica/fisiologia , Antagonistas Muscarínicos/farmacologia , Adulto , Complacência (Medida de Distensibilidade)/efeitos dos fármacos , Endossonografia/instrumentação , Feminino , Humanos , Técnicas In Vitro , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...