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1.
Environ Geochem Health ; 45(11): 7979-7997, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37515727

RESUMO

Nutrient management in resource conservation practices influence the structural and functional microbial diversities and thereby affect biological processes and biochemical properties in soil. We studied the long-term effects of resource conservation technologies on functional microbial diversity and their interactions with soil biochemical properties and enzymatic activities in tropical rice-green gram cropping system. The experiment includes seven treatments viz., conventional practice (CC), brown manuring (BM), green manuring (GM), wet direct drum sowing, zero tillage, green manuring-customized leaf colour chart based-N application (GM-CLCC-N) and biochar (BC) application. The result of the present study revealed that microbial biomass nitrogen (N), carbon (C) and phosphorus (P) in GM practice were increased by 23.3, 37.7 and 35.1%, respectively than CC. GM, BM and GM-CLCC-N treatments provide higher yields than conventional practice. The average well color development value, Shannon index and McIntosh index were significantly higher by 26.6%, 86.9% and 29.2% in GM as compared to control treatment. So, from this study we can conclude that resource conservation practices like GM, GM-CLCC N and BM in combination with chemical fertilizers provide easily decomposable carbon source to support the microbial growth. Moreover, dominance of microbial activity in biomass amended treatments (GM, GM-CLCC N and BM) indicated that these treatments could supply good amount of labile C sources on real time basis for microbial growth that may protect the stable C fraction in soil, hence could support higher yield and soil organic carbon build-up in long run under rice-green gram soil.


Assuntos
Oryza , Solo , Solo/química , Carbono/análise , Biomarcadores Ambientais , Indicadores de Qualidade em Assistência à Saúde , Agricultura/métodos , Fertilizantes , Nitrogênio/análise
2.
J Surg Educ ; 80(9): 1320-1339, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37516576

RESUMO

INTRODUCTION: Live anaesthetized animals are used as simulation models to teach techniques in the emergency management of trauma. We aimed to explore how "live tissue training" (LTT) is designed, delivered and evaluated in order to better understand and characterize aspects of educational merit. METHODS: A systematic review was performed using PRISMA guidance. A combined approach, involving a 3-stage modified narrative synthesis process and reflexive thematic analysis was used to identify key concepts across the published literature. FINDINGS: Qualitative synthesis of 48 selected articles suggests that LTT is mainly used to teach military and civilian physicians and military medical technicians. The procedures trained vary with the learner population, from simple pre-hospital trauma tasks to advanced operative surgical skills. Many courses use a combination of didactic and practical training, with an animal model used to train practical application of knowledge and procedural skills. Descriptions of the learning interventions are limited, and explicit use of educational theory or pedagogic frameworks were absent within the literature. Four themes were identified regarding aspects of LTT that are valued by learners: "recreating the experience," relating to fidelity and realism; "tick tock" "dynamics of hemorrhage", encompassing the impact of bleeding and urgent pressure to act; "emotional impact" of conducting the training, and "self-efficacy: I believe I can do it." CONCLUSION: Thematic analysis of published literature suggests that there may be educational benefit in the use of live tissue models due to time criticality and bleeding, which creates a real-life event. LTT also invokes an emotional response, and learners experience an increase in self-efficacy from participation. We consider that these aspects and associated pedagogy should be addressed when researching and developing alternative simulation modalities, in order to intelligently replace, reduce and refine the use of animals in training practitioners in the emergency management of trauma.


Assuntos
Médicos , Treinamento por Simulação , Animais , Humanos , Aprendizagem , Competência Clínica
3.
BMJ Mil Health ; 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35649691

RESUMO

INTRODUCTION: The acquisition and retention of militarily relevant surgical knowledge and skills are vital to enable expert management of combat casualties on operations. Opportunities for skill sustainment have reduced due to the cessation of combat operations in Iraq and Afghanistan and lack of military-relevant trauma in UK civilian practice. METHODS: A voluntary, anonymous online survey study was sent to all UK Defence Medical Services (DMS) surgical consultants and higher surgical trainees in Trauma and Orthopaedics, Plastic and Reconstructive, and General and Vascular surgical specialties (three largest surgical specialties in the DMS in terms of numbers). The online questionnaire tool included 20 questions using multiple choice and free text to assess respondents' subjective feelings of preparedness for deployment as surgeons for trauma patients. RESULTS: There were 71 of 108 (66%) responses. Sixty-four (90%) respondents were regular armed forces, and 46 (65%) worked in a Major Trauma Centre (MTC). Thirty-three (47%) had never deployed on operations in a surgical role. Nineteen (27%) felt they had sufficient exposure to penetrating trauma. When asked 'How well do you feel your training and clinical practice prepares you for a surgical deployment?' on a scale of 1-10, trainees scored significantly lower than consultants (6 (IQR 4-7) vs 8 (IQR 7-9), respectively; p<0.001). There was no significant difference in scores between regular and reservists, or between those working at an MTC versus non-MTC. Respondents suggested high-volume trauma training and overseas trauma centre fellowships, simulation, cadaveric and live-tissue training would help their preparedness. CONCLUSIONS: There was a feeling among a sample of UK DMS consultants and trainees that better preparedness is required for them to deploy confidently as a surgeon for combat casualties. The responses suggest that UK DMS surgical training requires urgent attention if current surgeons are to be ready for their role on deployed operations.

4.
BMJ Mil Health ; 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35772794

RESUMO

Haemorrhage from junctional injuries remains the most common cause of battlefield death. Changes to surgical training have meant acquiring and maintaining trauma surgical skills is becoming more difficult for military surgeons. The multidisciplinary Military Operational Specialist Team Training (MOSTT) course is designed to bridge the gap between civilian practice and the deployed environment, as part of predeployment trauma training. It involves immersive team simulation and uses cadaveric dissection for surgical skills practice.A novel surgical anatomy model, featuring junctional haemorrhage surgical task trainers of the groin and shoulder, was designed using reconstructed CT and MRI images obtained from a human volunteer. The model is designed to look and feel as realistic as possible, with the added dimension of pulsatile 'blood' flow from a simulation gunshot injury.This surgical anatomy model has been trialled, as part of the MOSTT course, by 90 surgeons and perioperative practitioners, with feedback analysis used for iterative model development. Feedback demonstrated that, alongside more traditional cadaveric dissection, this surgical anatomy model adds value to current predeployment training delivered within the immersive simulation of the MOSTT course. Research by the authors about the effects of this model on surgical ability and performance is ongoing. However, there is clear potential for this model to be used in other environments, including on exercises and as part of consolidation training while deployed.

5.
Sci Total Environ ; 665: 890-912, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30790762

RESUMO

This review covers the current and emerging analytical methods used in laboratory, field, landscape and regional contexts for measuring soil organic carbon (SOC) sequestration in agricultural soil. Soil depth plays an important role in estimating SOC sequestration. Selecting appropriate sampling design, depth of soil, use of proper analytical methods and base line selection are prerequisites for estimating accurately the soil carbon stocks. Traditional methods of wet digestion and dry combustion (DC) are extensively used for routine laboratory analysis; the latter is considered to be the "gold standard" and superior to the former for routine laboratory analysis. Recent spectroscopic techniques can measure SOC stocks in laboratory and in-situ even up to a deeper depth. Aerial spectroscopy using multispectral and/or hyperspectral sensors located on aircraft, unmanned aerial vehicles (UAVs) or satellite platforms can measure surface soil organic carbon. Although these techniques' current precision is low, the next generation hyperspectral sensor with improved signal noise ratio will further improve the accuracy of prediction. At the ecosystem level, carbon balance can be estimated directly using the eddy-covariance approach and indirectly by employing agricultural life cycle analysis (LCA). These methods have tremendous potential for estimating SOC. Irrespective of old or new approaches, depending on the resources and research needed, they occupy a unique place in soil carbon and climate research. This paper highlights the overview, potential limitations of various scale-dependent techniques for measuring SOC sequestration in agricultural soil.

6.
Int J Biometeorol ; 63(3): 337-349, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30680629

RESUMO

Photosynthetically active radiation (PAR) is one of the most important environmental factors that determine the productivity and grain quality of the crops. Continuous rainy days or cloudy weather throughout crop growth especially at critical stages often resulted in great loss of grain quality and yield in rice. Low light stress has rigorously constrained the rice production in various rice-growing regions, especially in Southeast Asia. Method and time of planting are the major management factors contributing to the higher yield potential of rice by influencing light harvesting and use efficiency. Present study was executed consecutively for 5 years (kharif seasons of 2012-2016) to determine whether planting time improves the radiation absorption and use efficiency in different duration rice cultivars. We evaluated the difference in plant growth and development leading to yield formation under different planting time which related to radiation incidence and interception. The results of the study revealed that PAR interception depends on morphological characters of cultivars and also with agronomic management such as transplanting time and method. Long duration cultivar intercepted more PAR but interception decreased due to late planting (3rd week of July), whereas short duration cultivars (Naveen) when planted earlier (1st week of June) could not effectively utilize intercepted PAR constraining the biomass accumulation and yield formation. Effect of planting density and crop architecture on PAR absorption was apparent among establishment methods as light interception at crop canopy was highest in the system of rice intensification and lowest in that of wet direct seeding. In general, Pooja as a long duration cultivar intercepted more PAR per day but when compared on same date of planting, the comparative absorption of radiation was 30.6% higher in Naveen. The lower yields in the wet season are attributed mostly to reduction in grain number per panicle or per unit land area, which is a consequence of high spikelet sterility. Grain yield of rice planted in July third week was reduced by 3.8, 12.3, and 6.9% over June first and third week and July first week, respectively, mainly due to spikelet sterility (26%) and lower grains per panicle (18%). Our results indicated that agronomic management like optimum time of sowing, cultivar duration, and establishment methods should be followed for yield improvement in tropical lowlands where light intensity is limiting due to prevailing weather situations.


Assuntos
Agricultura/métodos , Oryza/crescimento & desenvolvimento , Luz Solar , Folhas de Planta/crescimento & desenvolvimento , Estações do Ano , Temperatura
7.
Sci Total Environ ; 651(Pt 1): 84-92, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30223222

RESUMO

Methane (CH4) is predominantly produced in lowland rice soil, but its emission from soil to atmosphere primarily depends on passage/conduit or capillary pore spaces present in rice plants. The gas transport mechanism through aerenchyma pore spaces of rice cultivars was studied to explore the plant mediated CH4 emission. Seven rice cultivars, based on the life cycle duration (LCD), were tested in tropical eastern India. Three LCD groups were, (a) Kalinga 1 and CR Dhan 204 (LCD: 110-120 days); (b) Lalat, Pooja and CR 1014 (LCD: 130-150 days); and (c) Durga and Varshadhan (LCD: 160-170 days). Rate of CH4emission, root exudates, root oxidase activities and shoot aerenchyma pore spaces were analyzed to study the mechanism of plant mediated emission from rice. Aerenchyma pore space was quantified in the hypothesis that it regulates the CH4 transportation from soil to atmosphere. The ratio of pore space area to total space was lowest in Kalinga 1 cultivar (0.29) and highest was in Varshadhan (0.43). Significant variations in the methane emission were observed among the cultivars with an average emission rate ranged from 0.86 mg m-2 h-1 to 4.96 mg m-2 h-1. The CH4 emission rates were lowest in short duration cultivars followed by medium and long duration ones. The greenhouse gas intensity considering average CH4 emission rate per unit grain yield was also lowest (0.35) in Kalinga 1 and relatively less in short and medium duration cultivars. Root exudation was higher at panicle initiation (PI) than maximum tillering (MT) stage. Lowest exudation was noticed in (197.2 mg C plant-1 day-1) Kalinga 1 and highest in Varsadhan (231.7 mg C plant-1 day-1). So we can say, the rate of CH4 emission was controlled by aerenchyma orientation, root exudation and biomass production rate which are the key specific traits of a cultivar. Identified traits were closely associated with duration and adaptability to cultivars grown in specific ecology. Therefore, there is possibility to breed rice cultivars depending on ecology, duration and having less CH4 emission potential, which could be effectively used in greenhouse gas mitigation strategies.


Assuntos
Poluentes Atmosféricos/metabolismo , Metano/metabolismo , Oryza/metabolismo , Índia , Oryza/anatomia & histologia , Oryza/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismo , Clima Tropical
8.
Epidemiol Infect ; 145(16): 3525-3534, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29103405

RESUMO

Neisseria meningitidis is a gram-negative bacterium that lives as a commensal in the human nasopharynx. Meningococci are generally non-invasive, but can invade the nasopharyngeal epithelia and enter the bloodstream causing life-threatening illnesses. It is generally thought that meningococci do not survive for long outside the host, and that transmission requires relatively close contact between hosts. There are some reports, however, that meningococci can survive drying on surfaces, including glass, plastic and cloth. Our examination of N. meningitidis strains dried on glass showed differences in survival of isolates belonging to serogroups B, C and W135, including persistence of Cuban, New Zealand, and Norwegian epidemic strains up to 8 days, depending on temperature and humidity. Survival of a New Zealand epidemic strain isolate NZ98/254 under ambient conditions in the laboratory was greatest in winter suggesting that environmental factors impacted survival. For most isolates, including NZ98/254, survival under controlled conditions at 30 °C was greater at 22% than 30% relative humidity. There were also some differences in survival between carriage and invasive strains. The results suggest that N. meningitidis could be transmitted through contact with surfaces outside the host, potentially including contact through shared drinking vessels.


Assuntos
Fômites/microbiologia , Infecções Meningocócicas/microbiologia , Viabilidade Microbiana , Neisseria meningitidis/fisiologia , Neisseria meningitidis/patogenicidade , Microbiologia Ambiental , Humanos , Infecções Meningocócicas/transmissão
9.
World J Emerg Surg ; 10: 26, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161133

RESUMO

The United Kingdom National Health Service treats both elective and emergency patients and seeks to provide high quality care, free at the point of delivery. Equal numbers of emergency and elective general surgical procedures are performed, yet surgical training prioritisation and organisation of NHS institutions is predicated upon elective care. The increasing ratio of emergency general surgery consultant posts compared to traditional sub-specialities has yet to be addressed. How should the capability gap be bridged to equip motivated, skilled surgeons of the future to deliver a high standard of emergency surgical care? The aim was to address both training requirements for the acquisition of necessary emergency general surgery skills, and the formation of job plans for trainee and consultant posts to meet the current and future requirements of the NHS. Twenty nine trainees and a consultant emergency general surgeon convened as a Working Group at The Association of Surgeons in Training Conference, 2015, to generate a united consensus statement to the training requirement and delivery of emergency general surgery provision by future general surgeons. Unscheduled general surgical care provision, emergency general surgery, trauma competence, training to meet NHS requirements, consultant job planning and future training challenges arose as key themes. Recommendations have been made from these themes in light of published evidence. Careful workforce planning, education, training and fellowship opportunities will provide well-trained enthusiastic individuals to meet public and societal need.

10.
Surg Endosc ; 29(11): 3298-303, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25631114

RESUMO

INTRODUCTION: Here, we report the first series of patients with 1-year implantation of a novel, endoluminal, endoscopically delivered and retrieved gastro-duodeno-jejunal bypass sleeve (GJBS) (ValenTx, Inc. Carpinteria, CA, USA). In this report, we present the safety, feasibility of the device, weight loss, and changes in comorbidities. METHODS AND PROCEDURES: A prospective, single-center, 12-month trial was designed. The patients are morbidly obese individuals who meet the NIH criteria for bariatric surgery. The GJBS is a 120-cm sleeve secured at the esophago-gastric junction with endoscopic and laparoscopic techniques that is designed to create an endoluminal gastro-duodeno-jejunal bypass. The device was implanted and, at the completion of the trial, retrieved with an endoscopic technique. The primary endpoints were safety and incidence of adverse events. The secondary outcomes included the percentage of excess weight loss (EWL) and changes in comorbidities, specifically glucose control, use of antihyperglycemics, and changes in hemoglobin A1C levels. RESULTS: From July 2009 until October 2009, 13 patients were prospectively enrolled for the 1-year trial. The study included five men and eight women with a mean preoperative BMI of 42 kg/m(2). One patient was excluded, at the time of endoscopic evaluation, due to inflammation at the GE junction. Two additional patients required early explantation of the device, within the first 4 weeks, due to patient intolerance. Upon explant of the device, both patients' symptoms improved. In the remaining ten patients, the device was implanted, left in situ for 12 months, and then retrieved endoscopically. Safe delivery of the cuff at the gastro-esophageal junction was seen in all ten patients whom had device implants, without complication. No esophageal leak was seen immediately post-procedure or during follow-up. The sleeve device was well tolerated within the bowel lumen during the 12-month study, specifically, no bowel erosions, ulceration, or pancreatitis was observed. All ten patients reached the 1-year mark. Of the ten, six had fully attached and functional devices throughout the follow-up, verified by endoscopy. The mean percentage EWL, at 1 year, in this group was 54 %. In the remaining four patients, partial cuff detachment was observed at follow-up endoscopy. The percentage EWL was lower in this group. Of the six patients that reached a year with a fully attached device, five were followed at an average of 14-months post-explant (26 months from the time of device implant). These five maintained an average percentage EWL of 30 % at the 14-month post-explant follow-up. Co-morbidites measured included diabetes mellitus, hypertension, hyperlipidemia, and use of antihyperglycemics. Each of the measured comorbidities showed improvement during the 12-month trial. DISCUSSION: The endoluminal, GJBS can be safely placed and retrieved. The short-term data show it is well tolerated with a good safety profile. It achieves excellent weight loss results with over 70 % of all comorbidities resolved or significantly improved.


Assuntos
Endoscopia Gastrointestinal/instrumentação , Derivação Gástrica/instrumentação , Obesidade Mórbida/cirurgia , Adulto , Idoso , Remoção de Dispositivo , Endoscopia Gastrointestinal/métodos , Estudos de Viabilidade , Feminino , Seguimentos , Derivação Gástrica/métodos , Humanos , Laparoscopia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Próteses e Implantes , Resultado do Tratamento , Redução de Peso
12.
Ecotoxicol Environ Saf ; 114: 257-62, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24836933

RESUMO

Fly ash (FA), a byproduct of coal combustion in thermal power plants, has been considered as a problematic solid waste and its safe disposal is a cause of concern. Several studies proposed that FA can be used as a soil additive; however its effect on microbial response, soil enzymatic activities and heavy metal accumulation in soil and grain of rice (cv. Naveen) to fly ash (FA) application was studied in a pot experiment during dry season 2011 in an Inceptisol. Fly ash was applied at a rate of zero per cent (FS), five per cent (FA5), ten per cent (FA10), twenty per cent (FA20), 40 per cent (FA40) and 100 per cent (FA100) on soil volume basis with nitrogen (N), phosphorus (P) and potassium (K) (40:20:20mg N:P:Kkg(-1) soil) with six replications. Heavy metals contents in soil and plant parts were analysed after harvest of crop. On the other hand, microbial population and soil enzymatic activities were analysed at panicle initiation stage (PI, 65 days after transplanting) of rice. There was no significant change in the concentration of zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), cadmium (Cd) and chromium (Cr) with application of fly ash up to FA10. However, at FA100 there was significant increase of all metals concentration in soil than other treatments. Microorganisms differed in their response to the rate of FA application. Population of both fungi and actinomycetes decreased with the application of fly ash, while aerobic heterotrophic bacterial population did not change significantly up to FA40. On the other hand, total microbial activity measured in terms of Fluorescein diacetate (FDA) assay, and denitrifiers showed an increased trend up to FA40. However, activities of both alkaline and acid phosphatase were decreased with the application of FA. Application of FA at lower levels (ten to twenty per cent on soil volume basis) in soil enhanced micronutrients content, microbial activities and crop yield.


Assuntos
Cinza de Carvão/farmacologia , Metais Pesados/análise , Oryza/química , Microbiologia do Solo , Solo/química , Actinobacteria/isolamento & purificação , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Nitrogênio/metabolismo , Resíduos Sólidos
13.
Br J Anaesth ; 113(4): 695-707, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24699520

RESUMO

BACKGROUND: Isoflurane has been reported to induce caspase-3 activation, which may induce neurotoxicity and contribute to the pathogenesis of Alzheimer's disease. However, the underlying mechanism is largely unknown, especially whether or not isoflurane can induce ryanodine receptors (RyRs)-associated endoplasmic reticulum (ER) stress, leading to caspase-3 activation. We therefore assessed the effects of isoflurane on RyRs-associated ER stress. METHODS: We treated primary neurones from wild-type (C57BL/6J) mice with 1% and 2% isoflurane for 1, 3, or 6 h. We then measured levels of C/EBP homologous protein (CHOP) and caspase-12, two ER stress markers, using immunocytochemistry staining and western blotting analysis. Dantrolene (5 µM), the antagonist of RyRs, was used to investigate the role of RyRs in the isoflurane-induced ER stress and caspase-3 activation. RESULTS: Isoflurane 2% for 6 h treatment increased the levels of CHOP (876% vs 100%, P=0.00009) and caspase-12 (276% vs 100%, P=0.006), and induced caspase-3 activation in the neurones. The administration of 2% isoflurane for 3 h (shorter duration), however, only increased the levels of CHOP (309% vs 100%, P=0.003) and caspase-12 (266% vs 100%, P=0.001), without causing caspase-3 activation. The isoflurane-induced ER stress (CHOP: F=16.64, P=0.0022; caspase-12: F=6.13, P=0.0383) and caspase-3 activation (F=32.06, P=0.0005) were attenuated by the dantrolene treatment. CONCLUSIONS: These data imply that isoflurane might induce caspase-3 activation by causing ER stress through RyRs, and dantrolene could attenuate the isoflurane-induced ER stress and caspase-3 activation. Further investigations of the potential neurotoxicity of isoflurane are needed.


Assuntos
Anestésicos Inalatórios/farmacologia , Caspases/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Isoflurano/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Actinas/metabolismo , Animais , Western Blotting , Caspase 12/metabolismo , Caspase 3/metabolismo , Dantroleno/farmacologia , Ativação Enzimática/efeitos dos fármacos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Relaxantes Musculares Centrais/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Fator de Transcrição CHOP/metabolismo
14.
Surg Innov ; 20(4): 395-402, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23060531

RESUMO

BACKGROUND: The influence of endoscopic video camera (VC) image quality on surgical performance has not been studied. Flexible endoscopes are used as substitutes for laparoscopes in natural orifice translumenal endoscopic surgery (NOTES), but their optics are originally designed for intralumenal use. Manipulable wired or wireless independent VCs might offer advantages for NOTES but are still under development. OBJECTIVE: To measure the optical characteristics of 4 VC systems and to compare their impact on the performance of surgical suturing tasks. METHODS: VC systems included a laparoscope (Storz 10 mm), a flexible endoscope (Olympus GIF 160), and 2 prototype deployable cameras (magnetic anchoring and guidance system [MAGS] Camera and PillCam). In a randomized fashion, the 4 systems were evaluated regarding standardized optical characteristics and surgical manipulations of previously validated ex vivo (fundamentals of laparoscopic surgery model) and in vivo (live porcine Nissen model) tasks; objective metrics (time and errors/precision) and combined surgeon (n = 2) performance were recorded. RESULTS: Subtle differences were detected for color tests, and field of view was variable (65°-115°). Suitable resolution was detected up to 10 cm for the laparoscope and MAGS camera but only at closer distances for the endoscope and PillCam. Compared with the laparoscope, surgical suturing performances were modestly lower for the MAGS camera and significantly lower for the endoscope (ex vivo) and PillCam (ex vivo and in vivo). CONCLUSIONS: This study documented distinct differences in VC systems that may be used for NOTES in terms of both optical characteristics and surgical performance. Additional work is warranted to optimize cameras for NOTES. Deployable systems may be especially well suited for this purpose.


Assuntos
Endoscópios , Laparoscópios , Cirurgia Endoscópica por Orifício Natural/instrumentação , Cirurgia Endoscópica por Orifício Natural/métodos , Gravação em Vídeo/instrumentação , Animais , Processamento de Imagem Assistida por Computador , Laparoscopia/instrumentação , Laparoscopia/métodos , Modelos Animais , Distribuição Aleatória , Suínos
15.
Endoscopy ; 44(2): 161-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22109650

RESUMO

BACKGROUND AND STUDY AIMS: Open or laparoscopic gastrojejunostomy is an established treatment for malignant duodenal obstruction but may be associated with significant morbidity and mortality. The purpose of this study was to develop a model for an entirely endoscopic gastrojejunostomy to treat duodenal obstruction, and to compare this with the laparoscopic technique. METHODS: During the first part of the study the endoscopic technique was developed and tested in porcine nonsurvival and survival experiments (n=12). During the second part of the study (n=10), endoscopic gastrojejunostomy for duodenal occlusion was compared with laparoscopic gastrojejunostomy in a survival randomized controlled trial (RCT). For both groups duodenal occlusion was achieved by the laparoscopic approach. RESULTS: In the RCT, the median times for laparoscopic vs. endoscopic gastrojejunostomy were 70 minutes (interquartile range [IQR] 65-75) vs. 210 minutes (IQR 197-220; P=0.01). There was a trend toward increased anastomotic diameter at necropsy in the laparoscopic group (2 cm, IQR 2-3) compared to the endoscopic group (1.8 cm, IQR 1.6-1.8; P=0.06). One animal in the endoscopic group died secondarily to bowel ischemia from volvulus of the jejunal loop. One animal in the laparoscopic group was prematurely sacrificed due to extensive pulmonary congestion and edema. All anastomoses were intact and patent. CONCLUSIONS: Purely endoscopic gastrojejunostomy using the developed technique and devices is feasible and can result in adequate relief of duodenal obstruction. Endoscopic anastomoses tend to be smaller than laparoscopic anastomoses, with the procedures being more time-consuming and associated with higher complication rates.


Assuntos
Obstrução Duodenal/cirurgia , Endoscopia Gastrointestinal/métodos , Derivação Gástrica/métodos , Laparoscopia/métodos , Animais , Modelos Animais de Doenças , Endoscopia Gastrointestinal/instrumentação , Endoscopia Gastrointestinal/mortalidade , Feminino , Derivação Gástrica/instrumentação , Derivação Gástrica/mortalidade , Laparoscopia/instrumentação , Laparoscopia/mortalidade , Distribuição Aleatória , Sus scrofa , Resultado do Tratamento
16.
Surg Endosc ; 26(4): 1010-20, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22052424

RESUMO

BACKGROUND: Devices used for flexible intralumenal procedures are inadequate when used for intraperitoneal surgical procedures such as cholecystectomy. OBJECTIVE: To assess/address limitations of flexible endoscopic devices in intraperitoneal surgery. DESIGN: To describe processes used to invent new devices to facilitate this new surgical genre. SETTING: Engineering laboratory. PATIENTS: None. INTERVENTIONS AND INVENTIONS: Reviews of the limitations of flexible endoscopic instruments and instrumentation/invention needs for a "NOTES cholecystectomy" were completed. MAIN OUTCOME MEASURES: The appropriateness of existing methods of device innovation was evaluated against an inventory of new technologies necessary to perform NOTES. The deficiencies in traditional innovation methods led to the creation of a novel process for invention of new medical devices: the "Inventorama." METHODS: Cooperation between clinicians and industry to develop device concepts to enable NOTES. RESULTS: The devices included: (1) steerable flex trocar, (2) rotary access needle, (3) bipolar hemostasis forceps, (4) Maryland dissectors, (5) articulating hook knife, (6) rotating hook knife, (7) articulating graspers, (8) scissors, (9) ligating clip applier, and (10) tissue apposition system. Six of these ten were built and tested as initial crude prototypes in the Inventorama process; two underwent major modifications. Three were invented via alternate methods, including by independent clinicians. CONCLUSIONS: A new method for efficient medical device invention and development was created to address key technology needs for NOTES. The result was a "toolbox" of devices designed to address the key surgical activities necessary for advanced intralumenal and translumenal flexible endoscopic procedures.


Assuntos
Cirurgia Endoscópica por Orifício Natural/instrumentação , Dissecação/instrumentação , Desenho de Equipamento , Hemostasia Cirúrgica/instrumentação , Humanos , Ligadura/instrumentação , Instrumentos Cirúrgicos
17.
Surg Endosc ; 25(9): 3028-33, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21487876

RESUMO

BACKGROUND: This report describes the authors' experience with a unique endoluminal, endoscopically delivered and retrieved gastroduodenojejunal bypass sleeve, including short-term weight loss and changes in comorbidities. METHODS: A prospective, single-center trial was designed. The patients were morbidly obese individuals who met the National Institutes of Health criteria for bariatric surgery. The device used was a unique gastroduodenojejunal bypass sleeve secured at the esophagogastric junction with endoscopic and laparoscopic techniques and designed to create an endoluminal gastroduodenojejunal bypass. At completion of the trial, the device was explanted with endoscopic retrieval. The primary end points were safety and incidence of adverse events. The secondary outcomes included the percentage of excess weight loss and changes in comorbidities, specifically glucose control, use of antihyperglycemic medications, and changes in hemoglobin A1c levels. RESULTS: From July 2008 to February 2010, 24 patients were enrolled in the trial. The gastroduodenojejunal bypass sleeve was implanted, left in situ, and then retrieved. The 7 men and 17 women in the study had a mean preoperative body mass index of 42 kg/m(2). The device was successfully delivered in 22 of the 24 patients (92%) and retrieved endoscopically from all 22 patients in whom it was implanted (100%). Two patients were excluded from the study preprocedurally. The one patient was excluded preoperatively due to noncompliance with the preoperative liquid diet. For the other excluded patient, the device was not attempted endoscopically due to significant inflammation at the gastroesophageal junction at the time of laparoscopic evaluation. Of the 22 patients who had the device implanted, 17 maintained it (77%) and completed the full 12-week trial. These patients had 39.7% excess weight loss at completion of the study. The primary reason for early explantation of the device was early postoperative dysphagia. The seven patients with preoperative diabetes mellitus all had normal blood glucose levels throughout the trial, and none required antihyperglycemic medications. All four patients with elevated hemoglobin A1c levels preoperatively showed improvement by the end of the trial. CONCLUSIONS: This trial demonstrated that the endoluminal gastroduodenojejunal sleeve can achieve excellent weight loss at 12 weeks. No patient safety issues were encountered. Adverse effects were minimal and resolved at endoscopic device removal. Effective glycemic control was demonstrated through use of the device during the trial. Long-term results are needed.


Assuntos
Endoscopia Gastrointestinal/instrumentação , Derivação Gástrica/instrumentação , Adulto , Índice de Massa Corporal , Comorbidade , Transtornos de Deglutição/epidemiologia , Remoção de Dispositivo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia , Desenho de Equipamento , Feminino , Fluoroscopia , Hemoglobinas Glicadas/análise , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/cirurgia , Pessoa de Meia-Idade , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Complicações Pós-Operatórias/epidemiologia , Radiografia Intervencionista , Adulto Jovem
18.
Gastrointest Endosc ; 71(4): 835-41, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19942215

RESUMO

BACKGROUND: Current devices for hemostasis in flexible endoscopy are inferior to methods used during open or laparoscopic surgery and might be ineffective for natural orifice transluminal endoscopic surgery. OBJECTIVE: To compare new flexible bipolar forceps (FBF), designed principally for natural orifice transluminal endoscopic surgery, with laparoscopic bipolar forceps (LBF) for hemostasis of intra-abdominal porcine arteries. SETTING: Surgical laboratories in Europe and the United States. DESIGN AND INTERVENTIONS: New FBF for hemostasis (3.7-mm diameter), featuring electrode isolation, were compared with rigid 5-mm LBF (ERBE BiClamp LAP forceps) at recommended settings. A porcine model of acute hemostasis was prepared by suturing the uterine horns and cecum to the abdominal wall, exposing uterine arteries, ovarian pedicles, cecal mesenteric bundles, and the inferior mesenteric artery. This allowed access to 10 vessels in each pig by transabdominal laparoscopic devices or a transgastric double-channel gastroscope. Vessels were measured, coagulated at 4 and more points, and transected. Blood pressure was increased to more than 200 mm Hg for 10 minutes by administering phenylephrine. Delayed bleeding was identified. MAIN OUTCOME MEASUREMENTS: In 7 pigs, a total of 65 vessels (1.5-6.0 mm) were randomly allocated to FBF (n = 32) or LBF (n = 33). Successful hemostasis both before and after blood pressure increase was equivalent between the 2 groups (before: 88% FBF vs 88% LBF, not significant [NS]; after: 97% FBF vs 94% LBF, NS). With FBF, the number of seals per vessel was 4.8 vs 4.4 with LBF (NS). The energy used to create FBF seals was 19.8 J vs 38.2 J for LBF (P < .05). LIMITATIONS: Results from porcine studies may not reflect patient outcomes. CONCLUSIONS: In a porcine model, transgastric FBF endoscopic hemostasis was as effective as conventional laparoscopic hemostasis using LBF across a wide range of vessels.


Assuntos
Eletrocoagulação/instrumentação , Gastroscópios , Hemostasia Cirúrgica/instrumentação , Laparoscópios , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Instrumentos Cirúrgicos , Animais , Ceco/irrigação sanguínea , Desenho de Equipamento , Feminino , Artérias Mesentéricas/cirurgia , Artéria Mesentérica Inferior/cirurgia , Ovário/irrigação sanguínea , Suínos , Estudos de Tempo e Movimento , Artéria Uterina/cirurgia , Veias/cirurgia
19.
J Pediatr Gastroenterol Nutr ; 46(2): 172-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18223376

RESUMO

OBJECTIVE: Endoluminal gastroplication (EG) is emerging as a minimally invasive procedure for the treatment of gastroesophageal reflux disease (GERD). The aim of this study is to evaluate the medium-term outcomes after EG in a pediatric patient population. PATIENTS AND METHODS: Seventeen children with a median age of 12.4 years (range 6.1-15.9 years) with GERD underwent EG using a flexible endoscopic sewing device (EndoCinch) over a period of 3 years. Three plications were placed in the gastric tissue below the lower esophageal sphincter. Drug dose requirement, pH measurements, symptom severity and frequency, and validated Quality of Life in Reflux and Dyspepsia (QOLRAD) scores were compared before EG and 1 and 3 years after EG. Statistical analysis was performed using a Wilcoxon rank-sum test and P < 0.05 was the threshold for significance. RESULTS: All patients showed an immediate posttreatment improvement in symptom severity, symptom frequency, and quality of life scores. Completed 1- and 3-year data were obtained from 16 patients. Four cases (25%) required a repeat procedure as a result of recurrence of symptoms after 2 to 24 months. Fourteen patients (88%) at 1 year and 9 patients (56%) at 3 years remained without a need for any antireflux medication. A sustained improvement in heartburn (P = 0.004), regurgitation (P = 0.017), and vomiting (P = 0.018) was seen at 3 years. The total QOLRAD score (maximum of 175) improved from a median of 87 (range 69-142) to 156 (range 111-175) at 1 year (P < 0.0001) and 153.5 (range 55-174) at 3 years (P = 0.002). CONCLUSIONS: EG is an effective and safe procedure in children. It is a viable option for the treatment of GERD refractory to or dependent on antireflux medications.


Assuntos
Esfíncter Esofágico Inferior/cirurgia , Refluxo Gastroesofágico/cirurgia , Gastroscopia/métodos , Qualidade de Vida , Adolescente , Criança , Feminino , Seguimentos , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/patologia , Humanos , Concentração de Íons de Hidrogênio , Masculino , Complicações Pós-Operatórias , Inibidores da Bomba de Prótons/uso terapêutico , Recidiva , Reoperação , Índice de Gravidade de Doença , Falha de Tratamento , Resultado do Tratamento
20.
Toxicology ; 241(1-2): 1-10, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-17825971

RESUMO

The herbicide paraquat has been widely used throughout the world for almost 50 years and is important in sustainable agriculture. When used correctly the chemical poses no known risk to human health. However, it is acutely toxic, and can be fatal, if the concentrated product is ingested orally. Despite many years of research there is no successful treatment for paraquat intoxication. In recent years we have turned our attention to understanding how we can make the product safer, if it is accidentally or intentionally consumed. We present in this paper a novel approach aimed at safening the paraquat product, Gramoxone. Following our previous research on the site and mechanism of paraquat absorption from the gastrointestinal tract we have identified a new formulation of paraquat, Gramoxone INTEON that reduces the absorption of paraquat into the blood. This new formulation contains the polysaccharide, alginate, a natural product extracted from sea-weed. We have designed a preparation of paraquat and alginate with surfactants that is herbicidally active but has the unique property that it gels on contact with gastric acid in the stomach. The resulting mixture slows the dispersion and delivery of the toxic chemical to its site of absorption in the small intestine. Alginates also protect the mucosa against the damaging influence of topical gastric irritants, like paraquat. Our studies have shown that increasing the loading of alginate between 7 and 17 g/L causes a dose-related reduction in paraquat absorption in vitro in isolated rat ileum. This is also observed in vivo, as measured by paraquat plasma kinetics in the rabbit where the Area Under Curve (AUC 0-24h) was reduced from 33.8+/-3 for Gramoxone to 12.5+/-6 (microg/mL)h for a formulation containing 17 g/L alginate. Such a reduction in systemic exposure to paraquat is expected to reduce the acute oral toxicity of the formulation. This should be particularly effective in a vomiting species such as man since we have shown in this investigation that alginates not only reduce the peak plasma paraquat values but also delay the time to peak levels. This provides the opportunity for a more effective emetic response since the highly viscous gelled material should remain in the stomach for longer than the liquid Gramoxone. Further research is required to understand and optimise the safening and herbicidal characteristics of these alginate acid-triggered gel formulations of paraquat. However, we anticipate that this alginate technology in Gramoxone INTEON could have significant benefit in reducing human mortalities associated with the herbicide.


Assuntos
Alginatos/química , Alginatos/farmacologia , Herbicidas/administração & dosagem , Herbicidas/toxicidade , Paraquat/administração & dosagem , Paraquat/toxicidade , Animais , Antiácidos/farmacologia , Área Sob a Curva , Química Farmacêutica , Herbicidas/química , Técnicas In Vitro , Indicadores e Reagentes , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Marcação por Isótopo , Masculino , Paraquat/química , Coelhos , Ratos
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