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This paper presents data on pain perception in rats exposed to 6 GHz radiofrequency electromagnetic radiation (RF-EMR). Rats were divided into two groups: control (n = 10, 4 replicates per test) and RF-EMR exposed group (n = 10, 4 replicates per test). Nociceptive responses of the groups were measured using rodent analgesiometry. Rats were divided into control and RF-EMR exposed groups. Nociceptive responses were measured using rodent analgesiometry. RF-EMR exposed rats had a 15% delay in responding to hot plate thermal stimulation compared to unexposed rats. The delay in responding to radiant heat thermal stimulation was 21%. We determined that RF-EMR promoted the occurrence of pressure pain as statistical significance by + 42% (p < 0.001). We observed that RF-EMR exposure increased nociceptive pain by + 35% by promoting cold plate stimulation (p < 0.05). RF-EMR exposure did not affect thermal preference as statistical significance but did support the formation of pressure pain perception.
In this study, we present data on pain perception in rats exposed to 6GHz RF-EMR. RF-EMR exposed rats showed delayed responses to hot plate and radiant heat thermal stimulation. RF-EMR increased pressure and nociceptive pain as statistically significance. In particular, the effects of RF-EMR should be considered when assessing hyperalgesic and hypoalgesic symptoms in the clinic. The results of this study indicate the need to take precautions against the possible negative effects of RF-EMR on human health with the rise of 5G technology.
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Percepción del Dolor , Ondas de Radio , Animales , Ratas , Percepción del Dolor/efectos de la radiación , Ondas de Radio/efectos adversos , Masculino , Radiación Electromagnética , Ratas Sprague-Dawley , CalorRESUMEN
Speech signal is enriched with plenty of features used for biometrical recognition and other applications like gender and emotional recognition. Channel conditions manifested by background noise and reverberation are the main challenges causing feature shifts in the test and training data. In this paper, a hybrid speaker identification model for consistent speech features and high recognition accuracy is made. Features using Mel frequency spectrum coefficients (MFCC) have been improved by incorporating a pitch frequency coefficient from speech time domain analysis. In order to enhance noise immunity, we proposed a single hidden layer feed-forward neural network (FFNN) tuned by an optimized particle swarm optimization (OPSO) algorithm. The proposed model is tested using 10-fold cross-validation over different levels of Adaptive White Gaussian Noise (AWGN) (0-50 dB). A recognition accuracy of 97.83% was obtained from the proposed model in clean voice environments. However, a noisy channel is realized with lesser impact on the proposed model as compared with other baseline classifiers such as plain-FFNN, random forest (RF), K-nearest neighbour (KNN), and support vector machine (SVM).
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How dynamic activity in neural circuits gives rise to behavior is a major area of interest in neuroscience. A key experimental approach for addressing this question involves measuring extracellular neuronal activity in awake, behaving animals. Recently developed Neuropixels probes have provided a step change in recording neural activity in large tissue volumes with high spatiotemporal resolution. This protocol describes the chronic implantation of Neuropixels probes in mice and rats using compact and reusable 3D-printed fixtures. The fixtures facilitate stable chronic in vivo recordings in freely behaving rats and mice. They consist of two parts: a covered main body and a skull connector. Single-, dual- and movable-probe fixture variants are available. After completing an experiment, probes are safely recovered for reimplantation by a dedicated retrieval mechanism. Fixture assembly and surgical implantation typically take 4-5 h, and probe retrieval takes ~30 min, followed by 12 h of incubation in probe cleaning agent. The duration of data acquisition depends on the type of behavioral experiment. Since our protocol enables stable, chronic recordings over weeks, it enables longitudinal large-scale single-unit data to be routinely obtained in a cost-efficient manner, which will facilitate many studies in systems neuroscience.
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Conducta Animal/fisiología , Electrodos Implantados , Electrofisiología/métodos , Neuronas/fisiología , Animales , Ratones Endogámicos C57BL , Impresión Tridimensional , Ratas Long-Evans , Cráneo/diagnóstico por imagen , Cráneo/cirugía , Vigilia/fisiologíaRESUMEN
Measuring the dynamics of neural processing across time scales requires following the spiking of thousands of individual neurons over milliseconds and months. To address this need, we introduce the Neuropixels 2.0 probe together with newly designed analysis algorithms. The probe has more than 5000 sites and is miniaturized to facilitate chronic implants in small mammals and recording during unrestrained behavior. High-quality recordings over long time scales were reliably obtained in mice and rats in six laboratories. Improved site density and arrangement combined with newly created data processing methods enable automatic post hoc correction for brain movements, allowing recording from the same neurons for more than 2 months. These probes and algorithms enable stable recordings from thousands of sites during free behavior, even in small animals such as mice.
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Encéfalo/fisiología , Electrodos Implantados , Electrofisiología/instrumentación , Microelectrodos , Neuronas/fisiología , Potenciales de Acción , Algoritmos , Animales , Electrofisiología/métodos , Masculino , Ratones , Ratones Endogámicos C57BL , Miniaturización , RatasRESUMEN
Dopamine neurons mediate the association of conditioned stimuli (CS) with reward (unconditioned stimuli, US) by signaling the discrepancy between predicted and actual reward during the US. Some theoretical models suggest that learning is also influenced by the salience or associability of the CS. A hallmark of CS associability models is that they can explain latent inhibition, i.e., the observation that novel CS are more effectively learned than familiar CS. Novel CS are known to activate dopamine neurons, but whether those responses affect associative learning has not been investigated. Here, we used fiber photometry to characterize dopamine responses to inconsequential familiar and novel stimuli. Using bidirectional optogenetic modulation during conditioning, we then show that CS-evoked dopamine promotes conditioned responses. This suggests that Pavlovian conditioning is influenced by CS dopamine, in addition to US reward prediction errors. Accordingly, the absence of dopamine responses to familiar CS might explain their slower learning in latent inhibition.
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Aprendizaje por Asociación/fisiología , Condicionamiento Clásico/fisiología , Dopamina/metabolismo , Neuronas Dopaminérgicas/fisiología , Porción Compacta de la Sustancia Negra/metabolismo , Recompensa , Área Tegmental Ventral/metabolismo , Animales , Señales (Psicología) , Neuronas Dopaminérgicas/metabolismo , Aprendizaje , Ratones , Optogenética , Porción Compacta de la Sustancia Negra/diagnóstico por imagen , Fotometría , Corteza Prefrontal , Terminales Presinápticos , Reconocimiento en Psicología , Área Tegmental Ventral/diagnóstico por imagenRESUMEN
The visual system is composed of diverse cell types that encode distinct aspects of the visual scene and may form separate processing channels. Here we present further evidence for that hypothesis whereby functional cell groups in the dorsal lateral geniculate nucleus (dLGN) are differentially modulated during behavior. Using simultaneous multi-electrode recordings in dLGN and primary visual cortex (V1) of behaving mice, we characterized the impact of locomotor activity on response amplitude, variability, correlation and spatiotemporal tuning. Locomotion strongly impacts the amplitudes of dLGN and V1 responses but the effects on variability and correlations are relatively minor. With regards to tunings, locomotion enhances dLGN responses to high temporal frequencies, preferentially affecting ON transient cells and neurons with nonlinear responses to high spatial frequencies. Channel specific modulations may serve to highlight particular visual inputs during active behaviors.
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Cuerpos Geniculados/fisiología , Neuronas/fisiología , Corteza Visual/fisiología , Vías Visuales/fisiología , Percepción Visual/fisiología , Potenciales de Acción/fisiología , Animales , Linaje de la Célula/fisiología , Electrodos Implantados , Cuerpos Geniculados/citología , Locomoción/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/clasificación , Neuronas/citología , Técnicas Estereotáxicas , Corteza Visual/citología , Vías Visuales/citologíaRESUMEN
Sensory, motor and cognitive operations involve the coordinated action of large neuronal populations across multiple brain regions in both superficial and deep structures. Existing extracellular probes record neural activity with excellent spatial and temporal (sub-millisecond) resolution, but from only a few dozen neurons per shank. Optical Ca2+ imaging offers more coverage but lacks the temporal resolution needed to distinguish individual spikes reliably and does not measure local field potentials. Until now, no technology compatible with use in unrestrained animals has combined high spatiotemporal resolution with large volume coverage. Here we design, fabricate and test a new silicon probe known as Neuropixels to meet this need. Each probe has 384 recording channels that can programmably address 960 complementary metal-oxide-semiconductor (CMOS) processing-compatible low-impedance TiN sites that tile a single 10-mm long, 70 × 20-µm cross-section shank. The 6 × 9-mm probe base is fabricated with the shank on a single chip. Voltage signals are filtered, amplified, multiplexed and digitized on the base, allowing the direct transmission of noise-free digital data from the probe. The combination of dense recording sites and high channel count yielded well-isolated spiking activity from hundreds of neurons per probe implanted in mice and rats. Using two probes, more than 700 well-isolated single neurons were recorded simultaneously from five brain structures in an awake mouse. The fully integrated functionality and small size of Neuropixels probes allowed large populations of neurons from several brain structures to be recorded in freely moving animals. This combination of high-performance electrode technology and scalable chip fabrication methods opens a path towards recording of brain-wide neural activity during behaviour.
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Electrodos , Neuronas/fisiología , Silicio/metabolismo , Animales , Corteza Entorrinal/citología , Corteza Entorrinal/fisiología , Femenino , Masculino , Ratones , Movimiento/fisiología , Corteza Prefrontal/citología , Corteza Prefrontal/fisiología , Ratas , Semiconductores , Vigilia/fisiologíaRESUMEN
BACKGROUND: Acute mesenteric ischemia is a life-threatening vascular emergency resulting in tissue destruction due to ischemia-reperfusion injury. Melatonin, the primary hormone of the pineal gland, is a powerful scavenger of reactive oxygen species (ROS), including the hydroxyl and peroxyl radicals, as well as singlet oxygen, and nitric oxide. In this study, we aimed to investigate whether melatonin prevents harmful effects of superior mesenteric ischemia-reperfusion on intestinal tissues in rats. METHODS: Rats were randomly divided into three groups, each having 10 animals. In group I, the superior mesenteric artery (SMA) was isolated but not occluded. In group II and group III, the SMA was occluded immediately distal to the aorta for 60 minutes. After that, the clamp was removed and the reperfusion period began. In group III, 30 minutes before the start of reperfusion, 10 mg/kg melatonin was administered intraperitonally. All animals were sacrified 24 hours after reperfusion. Tissue samples were collected to evaluate the I/R-induced intestinal injury and bacterial translocation (BT). RESULTS: There was a statistically significant increase in myeloperoxidase activity, malondialdehyde levels and in the incidence of bacterial translocation in group II, along with a decrease in glutathione levels. These investigated parameters were found to be normalized in melatonin treated animals (group III). CONCLUSION: We conclude that melatonin prevents bacterial translocation while precluding the harmful effects of ischemia/reperfusion injury on intestinal tissues in a rat model of superior mesenteric artery occlusion.
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Antioxidantes/uso terapéutico , Traslocación Bacteriana/efectos de los fármacos , Melatonina/uso terapéutico , Isquemia Mesentérica/complicaciones , Oclusión Vascular Mesentérica/complicaciones , Daño por Reperfusión/tratamiento farmacológico , Animales , Antioxidantes/farmacología , Masculino , Melatonina/farmacología , Arteria Mesentérica Superior , Distribución Aleatoria , Ratas , Ratas WistarRESUMEN
Hydatid cyst is a parasitic infection mostly caused by Echinococcus granulosus. As transmission occurs from infected dogs, it is endemic in animal husbandry regions. Here four patients within the same family are presented. The first patient is a 10 year-old girl admitted with nausea, vomiting, and fever. On her physical examination, there were decreased respiratory sounds in the right lung, rales, and hepatomegaly. In the radiological examination, cysts were seen in both her lung and liver. After the confirmation of the diagnosis with a serological examination, surgical resection was performed, and albendazole treatment was given. On family screening, cysts were detected in the liver and spleen in her asymptomatic 6-year-old brother; in the lung, liver, spleen, and right kidney in her 33-year-old mother who had repeating abdominal pain; and in the liver and left kidney in her 33-year-old asymptomatic father. Hydatid cyst infection was serologically confirmed in all patients, and they were given albendazole and were surgically treated. In this case report, four patients in the same family and diagnosed as having hydatid cysts were presented. It was emphasized that once a hydatid cyst was diagnosed, family screening became important, in endemic regions in particular.
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Equinococosis/diagnóstico , Echinococcus granulosus , Dolor Abdominal , Adulto , Albendazol/uso terapéutico , Animales , Antihelmínticos/uso terapéutico , Niño , Perros , Equinococosis/tratamiento farmacológico , Equinococosis/cirugía , Familia , Femenino , Fiebre , Hepatomegalia , Humanos , Riñón/parasitología , Hígado/parasitología , Pulmón/parasitología , Imagen por Resonancia Magnética , Masculino , Náusea , Bazo/parasitología , Tomografía Computarizada por Rayos X , VómitosRESUMEN
Early kidney transplant loss as a result of acute thrombosis of the renal artery remains a constant and devastating complication, with an incidence of 0.2-7.5%. While uncommon, arterial obstruction in the early postoperative period is a surgical emergency and must be ruled out if previously established diuresis ceases suddenly. Arterial thrombosis may occur as a result of injury to a diseased artery, problems with anastomoses, hypercoagulability or malpositioning of the allograft. In this study, we analyzed data on a group of 105 renal transplant recipients who presented with acute postoperative graft dysfunction between January 2006 and May 2012, to identify cases of acute renal artery thrombosis. We report on our experience of immediate re-transplantation following early kidney transplant thrombosis. Overall, two (1.9%) patients suffered early (within 48 hours of surgery) allograft renal artery thrombosis. In both patients, transplantation had not been complicated by atherosclerotic lesions or other thrombophilic states and postoperative diuresis had been successfully achieved, but diuresis ceased abruptly during the early postoperative period. Emergent duplex ultrasound scans were performed and acute renal artery thrombosis was detected in both patients. The patients were operated immediately and retransplantation procedures were conducted. We have reported our experience of immediate retransplantation following early primary graft dysfunction due to renal artery thrombosis. In conclusion, close monitoring of postoperative diuresis and, if necessary, immediate retransplantation in this situation can prove to be a successful treatment for preventing graft loss.
A perda precoce de transplante renal resultante de trombose aguda da artéria renal permanece sendo uma complicação constante e devastadora, com uma incidência de 0,2-7,5%. Apesar de incomum, a obstrução da artéria no período pós-operatório imediato é uma emergência cirúrgica e deve ser descartada caso a diurese previamente estabelecida se interrompa de forma súbita. A trombose arterial pode ocorrer como resultado de dano à artéria previamente doente, problemas com anastomoses, hipercoagulabilidade ou mal posicionamento do enxerto. Neste estudo, analisamos os dados de 105 receptores de transplante renal que apresentaram disfunção aguda do enxerto no pós-operatório entre janeiro de 2006 e maio de 2012, para identificar casos de trombose aguda da artéria renal. Relatamos nossa experiência com retransplante imediato após trombose precoce de transplante renal. Ao todo, dois (1,9%) pacientes apresentaram trombose precoce (dentro de 48 horas após a cirurgia) da artéria renal do enxerto. Em ambos os casos, não haviam ocorrido complicações relacionadas a lesões ateroscleróticas ou outros estados trombofílicos durante o transplante, e a diurese pós-operatória havia sido estabelecida com sucesso, porém cessou bruscamente no pósoperatório imediato. Ecografia dúplex de emergência foi realizada e revelou trombose aguda de artéria renal nos dois pacientes. Os pacientes foram operados imediatamente, e foi realizado o retransplante. Relatamos nossa experiência com retransplante imediato após disfunção precoce do enxerto primário devido a trombose da artéria renal. Concluise que o monitoramento da diurese no pós-operatório e, se necessário, a realização do retransplante imediato nessa situação podem ser um tratamento bem-sucedido para evitar a perda do enxerto.
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Humanos , Arteria Renal , Trombosis , Trasplante de Riñón/efectos adversos , Periodo Posoperatorio , Trasplante de Riñón/métodos , Diuresis , AloinjertosRESUMEN
We report a case of right external iliac artery stenosis after kidney transplantation surgery caused by vascular clamp application injury. The patient presented with claudication of the ipsilateral lower limb and the lesion was diagnosed angiographically. The patient was treated with endovascular stent placement...
Relatamos um caso de estenose da artéria ilíaca externa direita após cirurgia de transplante renal causada por lesão durante a colocação de um clampe vascular. O paciente apresentou claudicação do membro inferior ipsilateral e a lesão foi diagnosticada angiograficamente. O paciente foi tratado com colocação de stent endovascular...
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Humanos , Masculino , Persona de Mediana Edad , Angioplastia de Balón , Arteria Ilíaca/fisiopatología , Trasplante de Riñón/rehabilitación , Angiografía/enfermería , Prevalencia , StentsRESUMEN
Solid organ transplantation is an important therapeutic choice to improve the life quality of patients with end-stage renal disease. Renal transplant recipients have to take immunosuppressive therapy to prevent transplant rejection. However, this treatment increases susceptibility to infection. Bartonella henselae causes systemic, disseminated and silent manifestations in healthy individuals, while the mortality rate is high in immunosuppressive patients in the case of untreated bartonellosis. The diagnosis of B.henselae infections is usually based on serological methods since they are practical, simple and rapid. Recent reports indicated that bartonellosis seen after liver or kidney transplantation have been increased. The aim of this study was to present the antibody seropositivity of B.henselae detected in the serum and plasma samples of renal transplant recipients. This study was aimed to evaluate the antibody seroprevalence in renal transplant recipients and also to compare the antibody results obtained from serum and plasma samples. A total of 59 renal transplant recipients (32 male, 27 female; age range: 20-65 years) followed by Transplantation Unit of Health, Research and Training Center of Pamukkale University, were included in the study. After suspension of lyophilised B.henselae ATCC 49882 (Houston-1); B.henselae co-cultivation to Vero cell culture was performed by the method recommended by Zbinden et al. [Clin Diagn Lab Immunol 1995; 2(6): 693-5]. The cells were taken to co-cultivation in flasks after development of monolayers. In house immunofluorescence antibody (IFA) method was performed with the use of infected cell-coated slides. B.henselae antibodies were studied at 1/64 screening dilution both in serum and plasma samples. In our study B.henselae antibody positivity rates found in serum and plasma samples of the patients were 16.9% (10/59) and 6.8% (4/59), respectively (Cohen κ= 0.37). This detected kappa value indicated that the results of serum and plasma samples revealed "fair agreement". It should be kept in mind that the use of plasma samples in IFA tests would increase the false negative results. Thus the results of this study supported the general approach for the preference of serum samples for serological tests.
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Anticuerpos Antibacterianos/sangre , Infecciones por Bartonella/epidemiología , Bartonella henselae/inmunología , Trasplante de Riñón , Adulto , Anciano , Infecciones por Bartonella/inmunología , Femenino , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Plasma/inmunología , Estudios Seroepidemiológicos , Suero/inmunología , Adulto JovenRESUMEN
BACKGROUND: The choice between subtotal thyroidectomy (STT) and total thyroidectomy (TT) for multinodular goiter (MNG) remains controversial. METHODS: Thyroid tissue samples of 34 patients who underwent TT for multinodular disease between October 2005 and June 2007 in Pamukkale University Hospital, Department of General Surgery were evaluated. Thyroid tissues weighing 2 g each from either side were separated from the main specimen to simulate the tissues that would be left behind if a subtotal resection were performed instead of a total resection. Ki-67 staining was performed. RESULTS: The mean age of subjects was 49.3 +/- 12 years and 25 (73.5%) were females. Papillary microcarcinomas were found in 4 patients, 1 of which was in a residual thyroid specimen (RTS). Micronodule formations were found in 73.5% of specimens simulating residual thyroid. While Ki-67 indexes of residual thyroid tissues were 4.65% in nodules and 1.91% in normal areas (P < .05), they were 5.42% and 2.84%, respectively, for nodular and normal areas in the main specimens (P < .05). CONCLUSION: Remnant thyroid tissues, following STT, have a high percentage of micronodule formation with a remarkable cellular proliferative activity.
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Bocio/patología , Bocio/cirugía , Tiroidectomía/métodos , Carcinoma Papilar/patología , Carcinoma Papilar/cirugía , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasia Residual , Estadísticas no Paramétricas , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Resultado del TratamientoRESUMEN
PURPOSE: We investigated whether Tempol, a water-soluble antioxidant, prevents the harmful effects of superior mesenteric ischemia/reperfusion on intestinal tissues in rats. METHODS: The rats were divided into three groups of 10. In group 1, the superior mesenteric artery (SMA) was isolated but not occluded, and in groups 2 and 3 the superior mesenteric artery was occluded for 60 min. After that, the clamp was removed and reperfusion began. In group 3, 5 min before the start of reperfusion, a bolus dose of 30 mg/kg Tempol was administered intravenously and continued at a dose of 30 mg/kg for 60 min. All animals were euthanized after 24 h and tissue samples were collected for analysis. RESULTS: There was a significant increase in myeloperoxidase activity, malondialdehyde levels, and the incidence of bacterial translocation in group 2, with a decrease in glutathione levels. These parameters were found to be normalized in group 3. The intestinal mucosal injury score in group 2 was significantly higher than those in groups 1 and 3. CONCLUSION: Tempol prevents bacterial translocation while precluding the harmful effects of ischemia/reperfusion injury on intestinal tissues in a rat model of superior mesenteric artery occlusion.
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Antioxidantes/farmacología , Arteriopatías Oclusivas/patología , Traslocación Bacteriana/efectos de los fármacos , Óxidos N-Cíclicos/farmacología , Mucosa Intestinal/patología , Arterias Mesentéricas/patología , Isquemia Miocárdica/complicaciones , Reperfusión Miocárdica/efectos adversos , Enfermedad Aguda , Animales , Antioxidantes/administración & dosificación , Óxidos N-Cíclicos/administración & dosificación , Mucosa Intestinal/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Arterias Mesentéricas/efectos de los fármacos , Modelos Animales , Isquemia Miocárdica/prevención & control , Neutrófilos/efectos de los fármacos , Neutrófilos/enzimología , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno , Marcadores de SpinRESUMEN
BACKGROUND: Secondary peritonitis causes considerable mortality and morbidity. New strategies have been introduced like relaparotomy and temporary abdominal closure in the management of such persistent intra-abdominal infections. MATERIALS AND METHODS: Rats were divided into five groups each having ten animals. After induction of peritonitis, relaparotomies were done, and the abdomen was closed by different temporary abdominal closure techniques. After performing two relaparotomies during a 48-h period, all fascias closed primarily and incisional tensile strengths, hydroxyproline contents, and adhesions were measured on the following seventh day. RESULTS: The median values of tensile strength and hydroxyproline concentrations were lowest in skin-only closure rats. Intraperitoneal adhesion scores were highest in Bogota bag closure group. CONCLUSION: Primary, Bogota bag, and polyprolene mesh closures seem to be safe in terms of early fascial wound healing. Although it is easy to perform, skin-only closure technique has deleterious effects on fascial wound healing probably due to fascial retraction. Interestingly, Bogota bag has caused increased intraperitoneal adhesion formation.
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Infecciones Bacterianas/patología , Infecciones Bacterianas/cirugía , Enfermedades del Ciego/patología , Enfermedades del Ciego/cirugía , Fascia/patología , Fasciotomía , Perforación Intestinal/patología , Perforación Intestinal/cirugía , Enfermedades Peritoneales/patología , Peritonitis/patología , Peritonitis/cirugía , Poliglactina 910 , Polipropilenos , Complicaciones Posoperatorias/patología , Mallas Quirúrgicas , Técnicas de Sutura , Cicatrización de Heridas/fisiología , Animales , Vendajes , Procedimientos Quirúrgicos Dermatologicos , Hidroxiprolina/análisis , Ratas , Ratas Sprague-Dawley , Reoperación , Piel/patología , Resistencia a la Tracción , Adherencias Tisulares/patologíaRESUMEN
BACKGROUND: Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-kappaB (NF-kappaB) activation. It has been shown to attenuate local harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent animal studies, a delaying effect of remote organ I/R injury on the healing of colonic anastomoses has been demonstrated. In this study we investigated whether PDTC prevents harmful systemic effects of superior mesenteric I/R on left colonic anastomosis in rats. METHODS: Anastomosis of the left colon was performed in 40 rats randomly allocated into the following four groups: (1) Sham-operated group (group I, n = 10)-simultaneously with colonic anastomosis, the superior mesenteric artery and collateral branches divided from the celiac axis and the inferior mesenteric artery were isolated but not occluded. (2) Sham+PDTC group (group II, n = 10)-identical to sham-operated rats except for the administration of PDTC (100 mg/kg IV bolus) 30 minutes prior to commencing the experimental period. (3) I/R group (group III, n = 10)-60 minutes of intestinal I/R by superior mesenteric artery occlusion. (4) PDTC-treated group (group IV, n = 10)-PDTC 100 mg/kg before and after the I/R. On postoperative day 6, all animals were sacrificed, and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for investigation of anastomotic hydroxyproline (HP) contents, perianastomotic malondialdehyde (MDA) levels, myeloperoxidase activity (MPO), and glutathione (GSH) level. RESULTS: There was a statistically significant decrease in anastomotic bursting pressure values, tissue HP content and GSH level, along with an increase in MDA level and MPO activity in group III, when compared to groups I, II, and IV (p < 0.05). However, PDTC treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP content and GSH level, along with a decrease in MDA level and MPO activity in group IV (p < 0.05). CONCLUSIONS: This study showed that PDTC treatment significantly prevented the delaying effect of remote organ I/R injury on anastomotic healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent for increasing the safety of the anastomosis during particular operations where remote organ I/R injury occurs.
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Antioxidantes/farmacología , Colon/cirugía , Pirrolidinas/farmacología , Daño por Reperfusión/prevención & control , Tiocarbamatos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Anastomosis Quirúrgica/efectos adversos , Anastomosis Quirúrgica/métodos , Animales , Colon/irrigación sanguínea , Colon/química , Enfermedades del Colon/cirugía , Modelos Animales de Enfermedad , Glutatión/análisis , Hidroxiprolina/análisis , Masculino , Malondialdehído/análisis , Peroxidasa/análisis , Distribución Aleatoria , Ratas , Ratas Wistar , Daño por Reperfusión/etiologíaRESUMEN
BACKGROUND: Tempol (Sigma-Aldrich, Steinheim, Germany) is a stable piperidine nitroxide of low molecular weight that permeates biologic membranes and scavenges superoxide anions in vitro. In recent animal studies, the delaying effect of intraperitoneal sepsis on the healing of colonic anastomoses has been shown. In this study we aimed to investigate the effects of Tempol on the healing of colonic anastomoses in the presence of polymicrobial sepsis. METHODS: Anastomosis of the left colon was performed on the day after cecal ligation and puncture (CLP) in 30 rats that were divided into 3 groups: sham-operated control (laparotomy and cecal mobilization, group I, n = 10), CLP (group II, n = 10), Tempol-treated group (30 mg/kg intravenously before the construction of colonic anastomosis, group III, n = 10). On postoperative day 6, all animals were killed and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for further investigation of anastomotic hydroxyproline (HP) contents, perianastomotic myeloperoxidase (MPO) activity, malondialdehyde (MDA), and glutathione (GSH) levels. RESULTS: There was a statistically significant increase in MPO activity and MDA levels in the CLP group (group II), along with a decrease in GSH levels, anastomotic HP contents, and bursting pressure values when compared with controls (group I). However, Tempol treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP contents, and GSH levels, along with a decrease in MPO activity and MDA levels in group III (P < .05). CONCLUSIONS: This study showed that Tempol treatment significantly prevented the delaying effect of CLP-induced polymicrobial sepsis on anastomotic healing in the left colon. Further clinical studies are needed to clarify whether Tempol may be a useful therapeutic agent to increase the safety of the anastomosis during particular surgeries in which sepsis-induced organ injury occurs.
Asunto(s)
Antioxidantes/farmacología , Colon , Óxidos N-Cíclicos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Anastomosis Quirúrgica/métodos , Animales , Biomarcadores/metabolismo , Colon/efectos de los fármacos , Colon/metabolismo , Colon/cirugía , Modelos Animales de Enfermedad , Estudios de Seguimiento , Glutatión/metabolismo , Hidroxiprolina/metabolismo , Laparotomía , Ligadura/efectos adversos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Peroxidasa/metabolismo , Complicaciones Posoperatorias/prevención & control , Punciones/efectos adversos , Ratas , Ratas Wistar , Sepsis/etiología , Sepsis/microbiología , Espectrofotometría , Marcadores de Spin , Cicatrización de Heridas/fisiologíaRESUMEN
BACKGROUND AND AIMS: Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl) is a water-soluble analogue of the spin label TEMPO. As an antioxidative agent, it is a member of nitroxides, which detoxifies superoxide and possibly other toxic radicals in vivo. In this study, we aimed to investigate whether tempol prevents harmful systemic effects of superior mesenteric ischemia-reperfusion on left colonic anastomosis in rats. MATERIALS AND METHODS: Anastomosis of the left colon was performed in 30 rats that were divided into three groups each having ten animals: sham-operated control (group I), 60 min of intestinal ischemia-reperfusion by superior mesenteric artery occlusion (group II), and tempol-treated group (30 mg/kg before and after the ischemia-reperfusion (group III). On postoperative day 5, all animals were killed and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for further investigation of anastomotic hydroxyproline content, perianastomotic malondialdehyde, and glutathione levels. RESULTS: There was a statistically significant increase in the quantity of myeloperoxidase activity and malondialdehyde levels in group II, along with a decrease in glutathione levels, anastomotic hydroxyproline content, and bursting pressure values when compared to controls. However, all of the investigated parameters were normalized in tempol-treated animals (group III). CONCLUSION: We conclude that tempol significantly prevents harmful systemic effects of reperfusion injury on colonic anastomoses in a rat model of superior mesenteric artery occlusion.
Asunto(s)
Antioxidantes/farmacología , Colon/cirugía , Óxidos N-Cíclicos/farmacología , Daño por Reperfusión/prevención & control , Cicatrización de Heridas/efectos de los fármacos , Anastomosis Quirúrgica , Animales , Antioxidantes/uso terapéutico , Constricción , Óxidos N-Cíclicos/uso terapéutico , Modelos Animales de Enfermedad , Masculino , Arteria Mesentérica Superior/cirugía , Ratas , Ratas Wistar , Marcadores de SpinRESUMEN
INTRODUCTION: Pyrrolidine dithiocarbamate (PDTC) is a low-molecular thiol antioxidant and potent inhibitor of nuclear factor-kappaB (NF-kappaB) activation. In recent animal studies, the delaying effect of intraperitoneal sepsis on healing of colonic anastomoses has been demonstrated. In this study, we aimed to investigate the effects of PDTC on healing of colonic anastomoses in the presence of intraperitoneal sepsis induced by a rodent model of cecal ligation and puncture (CLP). METHODS: Anastomosis of the left colon was performed on the day following CLP in 30 rats that were divided into three groups: sham-operated control (laparotomy and cecal mobilization, group I, n =10), cecal ligation and puncture (CLP) (group II, n = 10), PDTC-treated group (100 mg/kg IV before construction of the colonic anastomosis) (group III, n = 10). On postoperative day 6, all animals were sacrificed, and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for further investigation of colonic anastomotic hydroxyproline (HP) contents, perianastomotic myeloperoxidase (MPO) activity, and malondialdehyde (MDA) and glutathione (GSH) levels. RESULTS: There was a statistically significant increase in the activity of MPO and MDA levels in the CLP group (group II) along with a decrease in GSH levels, colonic anastomotic HP contents, and bursting pressure values when compared to controls (group I). However, PDTC treatment led to a statistically significant increase in the tissue HP contents, GSH levels, and colonic anastomotic bursting pressure values, along with a decrease in MPO activity and MDA levels in group III (p < 0.05). CONCLUSIONS: This study showed that PDTC treatment significantly prevented the delaying effect of CLP-induced intraperitoneal sepsis on anastomotic healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent to increase the safety of the anastomosis during particular operations where sepsis-induced injury occurs.