271 resultados para Acute spinal trauma
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Objectives (1) Study the effectiveness of intravariceal injection of n-butyl-2-cyanoacrylate to treat acute gastric variceal (GV) bleeding and (2) study the impact of the type of GV and hepatic function on endoscopic hemostasis and mortality outcomes. Methods Fourty-eight patients with acute GV bleeding underwent intravariceal injection of n-butyl-2-cyanoacrylate and were followed until death or study conclusion (12-52 months). Results Primary hemostasis (no re-bleeding within 48 h) was accomplished in 42 patients (87.5%). Appearance of the bleeding site at the time of initial endoscopy, grade of cirrhosis and location of GV were not significant predictors of immediate hemostasis. Early re-bleeding (48 h to 6 weeks) occurred in 20.5% of patients and late re-bleeding (beyond 6 weeks) in 20.5% of patients. While the Child-Pugh score was predictive of re-bleeding and mortality, the type of GV and stigmata at initial endoscopy were not significant predictors of re-bleeding and mortality. Over a mean follow-up of 18 months, mortality rates were 43.9% and bleeding was the commonest cause of death. Conclusion Endoscopic injection of n-butyl-2-cyanoacrylate is effective and safe for treating bleeding GV. Patients with poor hepatic function are at higher risk of re-bleeding and death after acute gastric variceal bleed.
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Ambient particles have been consistently associated with adverse health effects, yielding mainly high cardiorespiratory morbidity and mortality. Diesel engines represent a major source of particles in the urban scenario. We aimed to modify the composition of diesel particles, by means of different extraction procedures, to relate changes in chemical profile to corresponding indicators of respiratory toxicity. Male BALB/c mice were nasally instilled with saline, or with diesel particles, treated or not, and assigned to five groups: saline ( SHAM), intact diesel particles (DEP), and diesel particles previously treated with methanol ( METH), hexane ( HEX), or nitric acid (NA). Elemental composition and organic compounds were analyzed. Twenty-four hours after nasal instillation, respiratory parameters were measured and lung tissue was collected for histological analysis. Static elastance was significantly increased in groups DEP and MET in relation to the other groups. HEX and NA were different from DEP but not significantly different from SHAM and METH groups. The difference between dynamic and static elastance was increased in DEP, METH, and NA treatments; HEX was not statistically different from SHAM. DEP and METH groups presented significantly increased upper airways resistance, while DEP, METH, and NA showed higher peripheral airways resistance values. All groups had a higher total resistance than SHAM. DEP, METH, and NA showed significant increased infiltration of polymorphonuclear cells. In conclusion, diesel particles treated with hexane ( HEX) resulted in a respiratory-system profile very similar to that in SHAM group, indicating that hexane treatment attenuates pulmonary inflammation elicited by diesel particles.
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Background Changes in the shape of the capnogram may reflect changes in lung physiology. We studied the effect of different ventilation/perfusion ratios (V/Q) induced by positive end-expiratory pressures (PEEP) and lung recruitment on phase III slope (S(III)) of volumetric capnograms. Methods Seven lung-lavaged pigs received volume control ventilation at tidal volumes of 6 ml/kg. After a lung recruitment maneuver, open-lung PEEP (OL-PEEP) was defined at 2 cmH(2)O above the PEEP at the onset of lung collapse as identified by the maximum respiratory compliance during a decremental PEEP trial. Thereafter, six distinct PEEP levels either at OL-PEEP, 4 cmH(2)O above or below this level were applied in a random order, either with or without a prior lung recruitment maneuver. Ventilation-perfusion distribution (using multiple inert gas elimination technique), hemodynamics, blood gases and volumetric capnography data were recorded at the end of each condition (minute 40). Results S(III) showed the lowest value whenever lung recruitment and OL-PEEP were jointly applied and was associated with the lowest dispersion of ventilation and perfusion (Disp(R-E)), the lowest ratio of alveolar dead space to alveolar tidal volume (VD(alv)/VT(alv)) and the lowest difference between arterial and end-tidal pCO(2) (Pa-ETCO(2)). Spearman`s rank correlations between S(III) and Disp(R-E) showed a =0.85 with 95% CI for (Fisher`s Z-transformation) of 0.74-0.91, P < 0.0001. Conclusion In this experimental model of lung injury, changes in the phase III slope of the capnograms were directly correlated with the degree of ventilation/perfusion dispersion.
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Abrao J, Bianco MP, Roma W, Krippa JAS, Hallak JE - Spinal Myoclonus after Subarachnoid Anesthesia with Bupivacaine. Background and objectives: It is presented in this case report a very rare complication after spinal anesthesia to provide subsidies to the management and therapeutic conduct. Case report: This is a 63-year old African-Brazilian patient, ASA I, scheduled for transurethral resection of the prostate (TURP). He underwent subarachnoid anesthesia with bupivacaine (15 mg) without adrenaline. Intercurrences were not observed during puncture, and the patient was positioned for surgery. Soon after positioning the patient, he complained of severe pain in the perineum region followed by involuntary tonic-clonic movements of the lower limbs. The patient was treated with a benzodiazepine to control the myoclonus without response. This episode was followed by significant agitation and the patient was intubated. He was maintained in controlled ventilation and transferred to the Intensive Care Unit. Despite all biochemical and imaging tests performed, an apparent cause was not detected. The medication was not changed and the same batch of anesthetic had been used in other patients that same day without intercurrences. Conclusions: After ruling out all possible causes, the diagnosis of spinal myoclonus after spinal anesthesia with bupivacaine was made by exclusion.
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In order to qualify and quantify nerve fiber lesion following an acute crush injury, a morphologic and morphometric study was carried out in 25 Wistar rats divided into live groups of five animals each according to the crushing load applied, i.e., 500,1000, 5000, 10 000, and 15 000 g. The injury was produced under general anesthesia on a 5 mm-long intermediate segment of the right sciatic nerve for 10 min using a dead-weight machine. The animals were killed with an excessive dose of anesthetics 72 h later and submitted to perfusion with a fixing solution through the abdominal aorta immediately after death. Both the right and left sciatic nerves were removed and prepared for histologic and morphometric examinations: 5 mu m-thick sections stained with 1% Toluidine blue were examined under a light microscope equipped with a video camera linked to a computer loaded with a graphic program (KS 400). The morphometric studies included measuring total number of fibers, fiber density, fiber diameter, myelin fiber area, axon diameter, axon area and G ratio. The results showed that damage to the nerve fibers began to appear as early as with the 500g load and was similar in all groups despite the load applied, increasing with the 10000 and 15000g loads, although the external supporting tissues and small diameter fibers were preserved. The predominant type of lesion produced was axonotmesis. (c) 2008 Elsevier B.V. All rights reserved.
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Stimulating neural electrodes are required to deliver charge to an environment that presents itself as hostile. The electrodes need to maintain their electrical characteristics (charge and impedance) in vivo for a proper functioning of neural prostheses. Here we design implantable multi-walled carbon nanotubes coating for stainless steel substrate electrodes, targeted at wide frequency stimulation of deep brain structures. In well-controlled, low-frequency stimulation acute experiments, we show that multi-walled carbon nanotube electrodes maintain their charge storage capacity (CSC) and impedance in vivo. The difference in average CSCs (n = 4) between the in vivo (1.111 mC cm(-2)) and in vitro (1.008 mC cm(-2)) model was statistically insignificant (p > 0.05 or P-value = 0.715, two tailed). We also report on the transcription levels of the pro-inflammatory cytokine IL-1 beta and TLR2 receptor as an immediate response to low-frequency stimulation using RT-PCR. We show here that the IL-1 beta is part of the inflammatory response to low-frequency stimulation, but TLR2 is not significantly increased in stimulated tissue when compared to controls. The early stages of neuroinflammation due to mechanical and electrical trauma induced by implants can be better understood by detection of pro-inflammatory molecules rather than by histological studies. Tracking of such quantitative response profits from better analysis methods over several temporal and spatial scales. Our results concerning the evaluation of such inflammatory molecules revealed that transcripts for the cytokine IL-1 beta are upregulated in response to low-frequency stimulation, whereas no modulation was observed for TLR2. This result indicates that the early response of the brain to mechanical trauma and low-frequency stimulation activates the IL-1 beta signaling cascade but not that of TLR2.
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Background and Aims: Stress can alter many aspects of the immune response, and many studies have been conducted on the effects of stress on inflammatory processes, but little is known about its influence on the resolution of inflammation in tissue homeostasis, which includes the clearance of apoptotic cells by macrophages in a non-phlogistic way. In the present study, we investigated the effect of acute cold stress on the phagocytosis of apoptotic cells by macrophages. Methods: Mice were submitted to acute cold stress (4 degrees C for 4 h) and the capacity of peritoneal macrophages to phagocyte apoptotic thymocytes and to secrete anti-inflammatory cytokines was evaluated. Plasma corticosterone and catecholamine levels were investigated to assess their effect on the phagocytic capacity of macrophages in vitro. Results: We showed that acute cold stress decreases phagocytosis of apoptotic cells at the inflammatory site by lipopolysaccharide-activated macrophages but did not affect resting macrophages. The inhibitory effect on phagocytosis is accompanied by a reduced level of TGF-beta and higher IL-10 secretion. After stress, plasma concentrations of corticosterone increased 6-fold, epinephrine 2-fold and norepinephrine 1.7-fold compared to control mice. In vitro experiments showed that the decrease in phagocytosis after stress could be attributed, at least in part, to the effects of corticosterone; epinephrine and norepinephrine had no effect. Conclusions: The current study shows that acute cold stress decreases phagocytosis of apoptotic cells from an inflammatory environment by macrophages, and this inhibition is mediated by the intracellular glucocorticoid receptor. Copyright (C) 2009 S. Karger AG, Basel
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Tick bites may trigger acute phase responses. Positive and negative acute phase proteins were measured in infested cattle genetically resistant and susceptible to ticks. During heavier infestations levels of haptoglobin increased significantly in susceptible bovines; levels of serum amyloid A increased in resistant bovines; levels of alpha-l-acid glycoprotein decreased significantly in resistant bovines; levels of transferrin decreased significantly in susceptible bovines. In conclusion, tick infestations trigger acute phase responses and enhancement of specific acute phase proteins differs according to the genetic composition of hosts. Acute phase proteins may constitute useful biological signatures for monitoring the stress induced by tick infestations. (c) 2007 Elsevier Inc. All rights reserved.
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Objectives The study`s aims were to evaluate the antimycobacterial activity of 13 synthetic neolignan analogues and to perform structure activity relationship analysis (SAR). The cytotoxicity of the compound 2-phenoxy-1-phenylethanone (LS-2, 1) in mammalian cells, such as the acute toxicity in mice, was also evaluated. Methods The extra and intracellular antimycobacterial activity was evaluated on Mycobacterium tuberculosis H37Rv. Cytotoxicity studies were performed using V79 cells, J774 macrophages and rat hepatocytes. Additionally, the in-vivo acute toxicity was tested in mice. The SAR analysis was performed by Principal Component Analysis (PCA). Key findings Among the 13 analogues tested, LS-2 (1) was the most effective, showing promising antimycobacterial activity and very low cytotoxicity in V79 cells and in J774 macrophages, while no toxicity was observed in rat hepatocytes. The selectivity index (SI) of LS-2 (1) was 91 and the calculated LD50 was 1870 mg/kg, highlighting the very low toxicity in mice. SAR analysis showed that the highest electrophilicity and the lowest molar volume are physical-chemical characteristics important for the antimycobacterial activity of the LS-2 (1). Conclusions LS-2 (1) showed promising antimycobacterial activity and very weak cytotoxicity in cell culture, as well as an absence of toxicity in primary culture of hepatocytes. In the acute toxicity study there was an indication of absence of toxicity on murine models, in vivo.
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This study assessed the occurrence of human rhinovirus (HRV) species in outpatient children attending day-care in Sao Paulo, Brazil. HRV reverse transcriptase polymerase chain reaction and amplicon sequencing were done in 120 samples collected in 2008. HRV was detected in 27.5% of samples. HRV C was detected in 60.7% of wheezers, a frequency not different from that observed in nonwheezers (69.6%).
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Purpose of review Swelling is inexorably linked to shock and resuscitation in trauma. In many forms, swelling complicates and interacts with traumatic injury to raise pressures in the abdomen, resulting in intraabdominal hypertension, which may overtly manifest as abdominal compartment syndrome (ACS) driving multiple organ failure. Despite renewed clinical interest in posttraumatic intraabdominal pressure, there remains a chiasm between knowledge of the risks and clinical interventions to mitigate them. This review provides a concise overview of definitions, risk factors, diagnosis and management using an illustrative trauma case. Recent findings Intraabdominal pressure commonly increases following trauma, wherein ACS may manifest earlier than generally appreciated and complicate other insults such as shock and hemorrhage. Contemporary resuscitation strategies may exacerbate intraabdominal hypertension, particularly massive crystalloid resuscitation. Although unproven, the recent transition to crystalloid restriction and high plasma resuscitation strategies may influence the prevalence of ACS. Nonetheless, aggressive intraabdominal pressure monitoring should be mandatory in the critically ill. Despite potential nonoperative options, decompressive laparotomy remains the only definitive but often morbid treatment. Summary ACS results from many dysfunctions acting in concert with each other in self-propagating vicious cycles. Starting with greater awareness, it is imperative that the growing knowledge should be translated into clinical practice.
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Chagas disease (American trypanosomiasis) is caused by the protozoan parasite Trypanosoma cruzi. Chagas disease following solid-organ transplantation has occurred in Latin America. This report presents the occurrence of Chagas disease despite negative serological tests in both the donor and the recipient, as well as the effectiveness of treatment. A 21-year-old woman from the state of Sao Paulo (Brazil) underwent cadaveric donor liver transplantation in November 2005, due to cirrhosis of autoimmune etiology. Ten months after liver transplantation, she developed signs and symptoms of congestive heart failure (New York Heart Association functional class IV). The echocardiogram, which was normal preoperatively, showed dilated cardiac chambers, depressed left ventricular systolic function (ejection fraction = 35%) and moderate pulmonary hypertension. Clinical investigation discarded ischemic heart disease and autoimmune and other causes for heart failure. Immuno fluorescence (immunoglobulin M and immunoglobulin G) and hemagglutination tests for T cruzi were positive, and abundant T cruzi amastigotes were readily identified in myocardial biopsy specimens. Treatment with benznidazole for 2 months yielded an excellent clinical response. At the moment of submission, the patient remains in functional class I. This case highlighted that more appropriate screening for T cruzi infection is mandatory in potential donors and recipients of solid-organ transplants in regions where Chagas disease is prevalent. Moreover, it stressed that this diagnosis should always be considered in recipients who develop cardiac complications, since negative serological tests do not completely discard the possibility of disease transmission and since good results can be achieved with prompt trypanocidal therapy.
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Acute promyelocytic leukemia (APL) is characterized by a block in differentiation and accumulation of promyelocytes in the bone marrow and blood. The majority of APL patients harbor the t(15: 17) translocation leading to expression of the fusion protein promyelocytic-retinoic acid receptor alpha. Treatment with retinoic acid leads to degradation of promyelocytic-retinoic acid receptor alpha protein and disappearance of leukemic cells; however, 30% of APL patients relapse after treatment. One potential mechanism for relapse is the persistence of cancer ""stem"" cells in hematopoietic organs after treatment. Using a novel sorting strategy we developed to isolate murine myeloid cells at distinct stages of differentiation, we identified a population of committed myeloid cells (CD34(+), c-kit(+), Fc gamma RIII/II(+), Gr1(int)) that accumulates in the spleen and bone marrow in a murine model of APL. We observed that these cells are capable of efficiently generating leukemia in recipient mice, demonstrating that this population represents the APL cancer-initiating cell. These cells down-regulate the transcription factor CCAAT/enhancer binding protein alpha (C/EBP alpha) possibly through a methylation-dependent mechanism, indicating that C/EBP alpha deregulation contributes to transformation of APL cancer-initiating cells. Our findings provide further understanding of the biology of APL by demonstrating that a committed transformed progenitor can initiate and propagate the disease. (Blood. 2009; 114: 5415-5425)
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We studied the acute effect of intracranial hypertension (ICH) on gastric tonus of anesthetized rats. Brain ventricles were cannulated bilaterally for intracerebro-ventricular pressure (ICP) monitoring and ICH induction. Next, a balloon catheter was inserted at the proximal stomach and coupled to a barostat for gastric volume (GV) monitoring by plethysmography. Arterial pressure (AP) and heart rate (HR) were monitored continuously during 80-min. After a 20-min basal period, they were submitted to control or ICH protocols. In controls, the ICP varied spontaneously up to the end. Other rats were subjected to ICP rising to 10, 20, 40 or 60 mmHg and kept at these levels for 30-min. Another group was subjected after basal period to stepwise ICH (ICP rising to 20, 40 and 60 mmHg at every 10-min interval). Next, the ICH rats were monitored for further 30-min. Other rats, previously submitted to a subdiaphragmatic vagotomy, splanchnicectomy plus ganglionectomy or their respective sham surgery, were also studied under ICH. Each subset consisted of 5-6 rats. Data were compared to respective basal values after ANOVA and Bonferroni`s test. In controls, the CV, AP, HR values remained within stable levels. Besides inducing bradycardia and arterial hypertension, ICH10 mmHg decreased GV by 14.8% at the 50-min interval. In ICH20, 40 and 60 mmHg subsets, GV decreased 14.0, 24.5 and 30.6% at the 40-min interval, respectively. In stepwise ICH rats, GV decreased 10.2% and 12.7%, respectively under ICP of 40 and 60 mmHg. The GV values remained significantly lower than basal levels during the last 30-min of monitoring. Thus, ICH decreases the GV in an ICP-dependent pattern besides inducing Cushing`s reflex. (C) 2008 Published by Elsevier B.V.
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Loss-of-function mutations in telomerase complex genes can cause bone marrow failure, dyskeratosis congenita, and acquired aplastic anemia, both diseases that predispose to acute myeloid leukemia. Loss of telomerase function produces short telomeres, potentially resulting in chromosome recombination, end-to-end fusion, and recognition as damaged DNA. We investigated whether mutations in telomerase genes also occur in acute myeloid leukemia. We screened bone marrow samples from 133 consecutive patients with acute myeloid leukemia and 198 controls for variations in TERT and TERC genes. An additional 89 patients from a second cohort, selected based on cytogenetic status, and 528 controls were further examined for mutations. A third cohort of 372 patients and 384 controls were specifically tested for one TERT gene variant. In the first cohort, 11 patients carried missense TERT gene variants that were not present in controls (P<0.0001); in the second cohort, TERT mutations were associated with trisomy 8 and inversion 16. Mutation germ-line origin was demonstrated in 5 patients from whom other tissues were available. Analysis of all 3 cohorts (n = 594) for the most common gene variant (A1062T) indicated a prevalence 3 times higher in patients than in controls (n = 1,110; P = 0.0009). Introduction of TERT mutants into telomerase-deficient cells resulted in loss of enzymatic activity by haploinsufficiency. Inherited mutations in TERT that reduce telomerase activity are risk factors for acute myeloid leukemia. We propose that short and dysfunctional telomeres limit normal stem cell proliferation and predispose for leukemia by selection of stem cells with defective DNA damage responses that are prone to genome instability.