RESUMEN
During unresolved infections, some viruses escape immunological control and establish a persistant reservoir in certain cell types, such as human immunodeficiency virus (HIV), which persists in follicular helper T cells (TFH cells), and Epstein-Barr virus (EBV), which persists in B cells. Here we identified a specialized group of cytotoxic T cells (TC cells) that expressed the chemokine receptor CXCR5, selectively entered B cell follicles and eradicated infected TFH cells and B cells. The differentiation of these cells, which we have called 'follicular cytotoxic T cells' (TFC cells), required the transcription factors Bcl6, E2A and TCF-1 but was inhibited by the transcriptional regulators Blimp1, Id2 and Id3. Blimp1 and E2A directly regulated Cxcr5 expression and, together with Bcl6 and TCF-1, formed a transcriptional circuit that guided TFC cell development. The identification of TFC cells has far-reaching implications for the development of strategies to control infections that target B cells and TFH cells and to treat B cell-derived malignancies.
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Infecciones por Arenaviridae/inmunología , Linfocitos B/inmunología , Infecciones por Virus de Epstein-Barr/inmunología , VIH/inmunología , Virus de la Coriomeningitis Linfocítica/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular , Células Cultivadas , Regulación de la Expresión Génica , Centro Germinal/patología , Centro Germinal/virología , Factor Nuclear 1-alfa del Hepatocito/genética , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Proteínas Proto-Oncogénicas c-bcl-6/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Receptores CXCR5/genética , Receptores CXCR5/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
PURPOSE OF REVIEW: Patients suffering from chronic pancreatitis often require surgical intervention to treat their disease. This review discusses surgical options as well as reviews current trends and research in the operative management of chronic pancreatitis. RECENT FINDINGS: Relevant current topics in the field include the appropriate timing of surgery as well as the relative benefits of various procedures, particularly duodenum-preserving pancreatic head resection versus pancreaticoduodenectomy. Multiple studies have found that surgery earlier in the disease course results in improved outcomes. Furthermore, the recent literature reports similar outcomes of duodenum-preserving pancreatic head resection when compared with pancreaticoduodenectomy. SUMMARY: It is important for treating clinicians to be well versed on the interplay of medical, endoscopic, and surgical strategies to carefully tailor a patient's treatment plan. Each patient warrants careful consideration and an individualized approach in collaboration with multidisciplinary colleagues.
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Dolor Crónico/cirugía , Páncreas/cirugía , Pancreatitis Crónica/cirugía , Dolor Crónico/etiología , Progresión de la Enfermedad , Humanos , Pancreatectomía , Pancreaticoduodenectomía , Pancreatitis Crónica/complicacionesRESUMEN
OBJECTIVES: To assess the feasibility of inducing different severities of shock wave (SW)-induced traumatic brain injury (TBI) using lithotripsy. METHODS: Wistar rats (n = 36) were divided into 2 groups: group 1 (n = 20) received 5 SW pulses, and group 2 (n = 16) received 15 SWs pulses. The SW pulses were delivered to the right side of the frontal cortex. Neurologic and behavioral assessments (Garcia test, beam walking, rotarod, and elevated plus maze) were performed at the baseline and at 3, 6, 24, 72, and 168 hours after injury. At day 7 after injury (168 hours), we performed cerebral angiography to assess the presence of cerebral vasospasm and vascular damage due to SW-induced TBI. At the conclusion of the study, the animals were euthanized to assess damage to brain tissue using an overall histologic severity score. RESULTS: The Garcia score was significantly higher, and the anxiety index (based on the elevated plus maze) was significantly lower in group 1 compared to group 2 (P < .05). The anxiety index for group 1 returned to the baseline level in a fast nonlinear fashion, whereas the anxiety index for group 2 followed a distinct slow linear reduction. Cerebral angiograms revealed a more severe vasospasm for the animals in group 2 compared to group 1 (P = .027). We observed a statistically significant difference in the overall histologic severity scores between the groups. The median (interquartile range) overall histologic severity scores for groups 1 and 2 were 3.0 (2.75) and 6.5 (6.0), respectively (P = .023). CONCLUSIONS: We have successfully established different SW-induced TBI severities in our SW-induced TBI model by delivering different numbers of SW pulses to brain tissue.
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Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/etiología , Litotricia/efectos adversos , Animales , Conducta Animal , Encéfalo/diagnóstico por imagen , Angiografía Cerebral , Modelos Animales de Enfermedad , Estudios de Factibilidad , Litotricia/métodos , Masculino , Ratas Wistar , Índice de Severidad de la Enfermedad , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/etiologíaRESUMEN
Antiretroviral therapy can reduce HIV-1 to undetectable levels in peripheral blood, but the effectiveness of treatment in suppressing replication in lymphoid tissue reservoirs has not been determined. Here we show in lymph node samples obtained before and during 6 mo of treatment that the tissue concentrations of five of the most frequently used antiretroviral drugs are much lower than in peripheral blood. These lower concentrations correlated with continued virus replication measured by the slower decay or increases in the follicular dendritic cell network pool of virions and with detection of viral RNA in productively infected cells. The evidence of persistent replication associated with apparently suboptimal drug concentrations argues for development and evaluation of novel therapeutic strategies that will fully suppress viral replication in lymphatic tissues. These strategies could avert the long-term clinical consequences of chronic immune activation driven directly or indirectly by low-level viral replication to thereby improve immune reconstitution.
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Fármacos Anti-VIH/farmacocinética , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/fisiología , Tejido Linfoide/metabolismo , Replicación Viral , Adolescente , Adulto , Niño , Preescolar , Femenino , Semivida , Humanos , Masculino , Adulto JovenRESUMEN
Highly active antiretroviral therapy (HAART) can suppress HIV-1 replication and normalize the chronic immune activation associated with infection, but restoration of naïve CD4+ T cell populations is slow and usually incomplete for reasons that have yet to be determined. We tested the hypothesis that damage to the lymphoid tissue (LT) fibroblastic reticular cell (FRC) network contributes to naïve T cell loss in HIV-1 infection by restricting access to critical factors required for T cell survival. We show that collagen deposition and progressive loss of the FRC network in LTs prior to treatment restrict both access to and a major source of the survival factor interleukin-7 (IL-7). As a consequence, apoptosis within naïve T cell populations increases significantly, resulting in progressive depletion of both naïve CD4+ and CD8+ T cell populations. We further show that the extent of loss of the FRC network and collagen deposition predict the extent of restoration of the naïve T cell population after 6 month of HAART, and that restoration of FRC networks correlates with the stage of disease at which the therapy is initiated. Because restoration of the FRC network and reconstitution of naïve T cell populations are only optimal when therapy is initiated in the early/acute stage of infection, our findings strongly suggest that HAART should be initiated as soon as possible. Moreover, our findings also point to the potential use of adjunctive anti-fibrotic therapies to avert or moderate the pathological consequences of LT fibrosis, thereby improving immune reconstitution.
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Terapia Antirretroviral Altamente Activa/efectos adversos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , VIH-1 , Tejido Linfoide/inmunología , Adulto , Terapia Antirretroviral Altamente Activa/métodos , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Supervivencia Celular/efectos de los fármacos , Femenino , Fibrosis , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Humanos , Interleucina-7/inmunología , Tejido Linfoide/patología , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
Loss of the fibroblastic reticular cell (FRC) network in lymphoid tissues during HIV-1 infection has been shown to impair the survival of naive T cells and limit immune reconstitution after antiretroviral therapy. What causes this FRC loss is unknown. Because FRC loss correlates with loss of both naive CD4 and CD8 T-cell subsets and decreased lymphotoxin-ß, a key factor for maintenance of FRC network, we hypothesized that loss of naive T cells is responsible for loss of the FRC network. To test this hypothesis, we assessed the consequences of antibody-mediated depletion of CD4 and CD8 T cells in rhesus macaques and sooty mangabeys. We found that only CD4 T-cell depletion resulted in FRC loss in both species and that this loss was caused by decreased lymphotoxin-ß mainly produced by the CD4 T cells. We further found the same dependence of the FRC network on CD4 T cells in HIV-1-infected patients before and after antiretroviral therapy and in other immunodeficiency conditions, such as CD4 depletion in cancer patients induced by chemotherapy and irradiation. CD4 T cells thus play a central role in the maintenance of lymphoid tissue structure necessary for their own homeostasis and reconstitution.
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Linfocitos T CD4-Positivos/inmunología , Homeostasis/inmunología , Sistema Inmunológico/inmunología , Tejido Linfoide/inmunología , Animales , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Cercocebus atys , Infecciones por VIH/inmunología , Infecciones por VIH/metabolismo , Humanos , Sistema Inmunológico/citología , Sistema Inmunológico/metabolismo , Inmunohistoquímica , Depleción Linfocítica , Tejido Linfoide/metabolismo , Linfotoxina beta/inmunología , Linfotoxina beta/metabolismo , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/metabolismoRESUMEN
1. An equal-dose combination of tiletamine and zolazepam (Telazol®) is used as a veterinary anesthetic. There also have been reports of human abuse of Telazol®. The pharmacokinetics and metabolic fate of tiletamine and zolazepam and the rationale for their administration as an equal-dose combination are unclear. 2. The single-dose pharmacokinetics of intramuscular tiletamine and zolazepam (3 mg/kg each) in 16 Yorkshire-crossbred pigs were determined. The metabolites of tiletamine and zolazepam in pig plasma and urine were identified by mass spectrometry. The metabolic stability of tiletamine and zolazepam and the kinetics of formation of their metabolites by pig- and human-liver microsomes were determined. 3. Higher concentrations of zolazepam were observed in pig plasma and it was cleared more slowly compared to tiletamine (apparent clearance: 11 versus 134 l/h; half-life: 2.76 versus 1.97 h). Three metabolites of zolazepam and one metabolite of tiletamine were identified in pig urine, plasma and in microsomal incubations. In vitro formation of each of these metabolites in microsomes was biphasic involving a high-affinity/low-capacity and a low-affinity/high-capacity enzyme. The in vitro metabolic stability of tiletamine was considerably lower compared to zolazepam. 4. These results collectively point to major pharmacokinetic and metabolic differences between the two components of this fixed-dose anesthetic combination.
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Microsomas Hepáticos/efectos de los fármacos , Tiletamina/administración & dosificación , Tiletamina/farmacocinética , Zolazepam/administración & dosificación , Zolazepam/farmacocinética , Animales , Combinación de Medicamentos , Quimioterapia Combinada/métodos , Humanos , Inyecciones Intramusculares , Masculino , Especificidad de la Especie , Porcinos , Tiletamina/sangre , Tiletamina/orina , Zolazepam/sangre , Zolazepam/orinaRESUMEN
BACKGROUND: Cardiac output (CO) is a valuable proxy for perfusion, and governs volume responsiveness during resuscitation from distributive shock. The underappreciated venous system has nuanced physiology that confers valuable hemodynamic information. In this investigation, deconvolution of the central venous waveform by the fast Fourier transformation (FFT) algorithm is performed to assess its ability to constitute a CO surrogate in a porcine model of endotoxemia-induced distributive hypotension and resuscitation. STUDY DESIGN: Ten pigs were anesthetized, catheterized, and intubated. A lipopolysaccharides infusion protocol was used to precipitate low systemic vascular resistance hypotension. Four crystalloid boluses (10 cc/kg) were then given in succession, after which heart rate, mean arterial pressure, thermodilution-derived CO, central venous pressure (CVP), and the central venous waveform were collected, the last undergoing fast Fourier transformation analysis. The amplitude of the fundamental frequency of the central venous waveform's cardiac wave (f0-CVP) was obtained. Heart rate, mean arterial pressure, CVP, f0-CVP, and CO were plotted over the course of the boluses to determine whether f0-CVP tracked with CO better than the vital signs, or than CVP itself. RESULTS: Distributive hypotension to a 25% mean arterial pressure decrement was achieved, with decreased systemic vascular resistance (mean 918 ± 227 [SD] dyne/s/cm-5 vs 685 ± 180 dyne/s/cm-5; p = 0.038). Full hemodynamic parameters characterizing this model were reported. Slopes of linear regression lines of heart rate, mean arterial pressure, CVP, f0-CVP, and CO were -2.8, 1.7, 1.8, 0.40, and 0.35, respectively, demonstrating that f0-CVP values closely track with CO over the 4-bolus range. CONCLUSIONS: Fast Fourier transformation analysis of the central venous waveform may allow real-time assessment of CO during resuscitation from distributive hypotension, possibly offering a venous-based approach to clinical estimation of volume responsiveness.
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Endotoxemia , Hipotensión , Porcinos , Animales , Gasto Cardíaco/fisiología , Hemodinámica , Hipotensión/etiología , Hipotensión/terapia , Resucitación/métodosRESUMEN
BACKGROUND: Blood operations are constrained by many limitations in combat settings. As a result there are many challenges that require innovative solutions. STUDY DESIGN AND METHODS: This is a descriptive overview of blood product usage and transfusion medicine adaptations that have been employed by the US military to support combat operations in Iraq and Afghanistan between November 2001 and December 2010. RESULTS: Transfusion medicine challenges have included the need for rapid transport of large quantities of blood products from the United States to Iraq and Afghanistan, risks and appropriate countermeasures associated with blood products collected in the theater of operations, availability of fresh-frozen plasma at forward surgical facilities, need for platelets (PLTs) in combat, and the need to support constant and evolving changes in transfusion and resuscitation protocols. A decrease in the storage age of red blood cells (RBCs) transfused to combat casualties has been achieved. There has been an increase in the ratio of plasma and PLTs to RBCs transfused, increased availability of plasma and apheresis PLTs to facilitate this approach, and a continuous effort to improve the safety of using fresh whole blood and apheresis PLTs collected in combat. A number of clinical practice guidelines are in place to address these processes. CONCLUSION: This multidisciplinary approach has successfully addressed many complicated and challenging issues regarding blood operations and transfusion practices for combat casualties.
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Transfusión Sanguínea , Medicina Militar , Guerra , Donantes de Sangre , Conservación de la Sangre , Humanos , PlaquetoferesisRESUMEN
OBJECTIVES: Thrombotic complications after total pancreatectomy with islet autotransplantation (TPIAT) are common. However, the systemic changes to coagulation in the perioperative period have not been well studied. Our objective was to evaluate the derangements in coagulation in the perioperative period for this procedure. METHODS: This was a prospective observational study of patients undergoing elective TPIAT for chronic pancreatitis. Multiple methods of evaluating coagulation, including 2 viscoelastic assays and standard laboratory assays were obtained at defined intraoperative and postoperative intervals. RESULTS: Fifteen patients were enrolled. Laboratory values demonstrated initial intraoperative hypercoagulability before significant systemic anticoagulation after islet infusion with heparin. Hypercoagulability is again seen at postoperative days 3 and 7. Subgroup analysis did not identify any major coagulation parameters associated with portal vein thrombosis formation. CONCLUSIONS: Apart from the immediate period after islet cell and heparin infusion, patients undergoing TPIAT are generally hypercoagulable leading to a high rate of thrombotic complications. Portal vein thrombosis development had minimal association with systemic derangements in coagulation as it is likely driven by localized inflammation at the time of islet cell infusion. This study may provide the groundwork for future studies to identify improvements in thrombotic complications.
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Trasplante de Islotes Pancreáticos , Pancreatitis Crónica , Trombofilia , Trombosis de la Vena , Anticoagulantes , Heparina/uso terapéutico , Humanos , Trasplante de Islotes Pancreáticos/efectos adversos , Trasplante de Islotes Pancreáticos/métodos , Pancreatectomía/efectos adversos , Pancreatectomía/métodos , Pancreatitis Crónica/cirugía , Trombofilia/cirugía , Trasplante Autólogo/métodos , Resultado del Tratamiento , Trombosis de la Vena/etiologíaRESUMEN
BACKGROUND: Cytochrome-P450 enzymes metabolize most administered drugs. A variety of clinical conditions affect the CYP system. However, the effect of hemorrhagic shock on CYP-mediated drug metabolism in clinical setting or in clinically applicable in-vivo models is largely unknown. Simultaneous administration of multiple CYP enzyme-selective drugs is a technique to ascertain a population's metabolic profile with a limited number of subjects. MATERIALS AND METHODS: Pigs were used as experimental animals as they possess CYP functionality similar to humans. Three probe drugs (dextromethorphan [CYP2D6], flurbiprofen [CYP2C9], and midazolam [CYP3A4]; doses: 0.5, 0.25, and 0.5 mg/kg, respectively) were administered intravenously to six Yorkshire-crossbred pigs in healthy state. Hemorrhagic shock was induced in six (four from healthy group after a 7-d washout period and two additional) pigs and the same doses of probe drugs were administered after a 14-h resuscitation phase. Blood samples were collected periodically in both phases and analyzed for parent drugs and metabolites (dextrorphan, 4'-hydroxy-flurbiprofen and 1'-hydroxy-midazolam) to calculate pharmacokinetic parameters. A comprehensive set of biochemical and physiologic markers of shock was also recorded. RESULTS: No changes in parent drug clearances were observed post-shock. Extensive metabolite formation with apparent higher exposure to total (conjugated and unconjugated) dextrorphan (p = 0.08), 4'-hydroxy-flurbiprofen (p = 0.11) and 1'-hydroxy-midazolam (p = 0.09) were observed post-shock. CONCLUSIONS: The metabolic capacity of CYP enzymes did not appear to be severely hindered in resuscitative phase of hemorrhagic shock. Diminished renal secretory function caused by hemorrhagic shock may be the cause of metabolite accumulation in plasma.
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Sistema Enzimático del Citocromo P-450/metabolismo , Dextrometorfano/farmacocinética , Flurbiprofeno/farmacocinética , Midazolam/farmacocinética , Choque Hemorrágico/metabolismo , Animales , Biomarcadores/metabolismo , Dextrometorfano/administración & dosificación , Dextrometorfano/metabolismo , Relación Dosis-Respuesta a Droga , Flurbiprofeno/administración & dosificación , Flurbiprofeno/metabolismo , Inyecciones Intravenosas , Midazolam/administración & dosificación , Midazolam/metabolismo , Modelos Animales , Resucitación , Choque Hemorrágico/fisiopatología , PorcinosRESUMEN
INTRODUCTION: Lung injury has several inciting etiologies ranging from trauma (contusion and hemorrhage) to ischemia reperfusion injury. Reflective of the injury, tissue and cellular injury increases proportionally with the injury stress and is an area of potential intervention to mitigate the injury. This study aims to evaluate the therapeutic benefits of recombinant human MG53 (rhMG53) protein in porcine models of acute lung injury (ALI). MATERIALS AND METHODS: We utilized live cell imaging to monitor the movement of MG53 in cultured human bronchial epithelial cells following mechanical injury. The in vivo efficacy of rhMG53 was evaluated in a porcine model of hemorrhagic shock/contusive lung injury. Varying doses of rhMG53 (0, 0.2, or 1 mg/kg) were administered intravenously to pigs after induction of hemorrhagic shock/contusive induced ALI. Ex vivo lung perfusion system enabled assessment of the isolated porcine lung after a warm ischemic induced injury with rhMG53 supplementation in the perfusate (1 mg/mL). RESULTS: MG53-mediated cell membrane repair is preserved in human bronchial epithelial cells. rhMG53 mitigates lung injury in the porcine model of combined hemorrhagic shock/contusive lung injury. Ex vivo lung perfusion administration of rhMG53 reduces warm ischemia-induced injury to the isolated porcine lung. CONCLUSIONS: MG53 is an endogenous protein that circulates in the bloodstream. Therapeutic treatment with exogenous rhMG53 may be part of a strategy to restore (partially or completely) structural morphology and/or functional lung integrity. Systemic administration of rhMG53 constitutes a potential effective therapeutic means to combat ALI.
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Lesión Pulmonar Aguda , Daño por Reperfusión , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/etiología , Animales , Proteínas Portadoras , Modelos Animales de Enfermedad , Pulmón , Proteínas Recombinantes/metabolismo , Daño por Reperfusión/complicaciones , Daño por Reperfusión/tratamiento farmacológico , PorcinosRESUMEN
Circulating microRNAs (miRNAs) can be biomarkers for diagnosis and progression of several pathophysiological conditions. In a cohort undergoing total pancreatectomy with islet autotransplantation (TPIAT) from the multicenter Prospective Observational Study of TPIAT (POST), we investigated associations between a panel of circulating miRNAs (hsa-miR-375, hsa-miR-29b-3p, hsa-miR-148a-3p, hsa-miR-216a-5p, hsa-miR-320d, hsa-miR-200c, hsa-miR-125b, hsa-miR-7-5p, hsa-miR-221-3p, hsa-miR-122-5p) and patient, disease and islet-isolation characteristics. Plasma samples (n = 139) were collected before TPIAT and miRNA levels were measured by RTPCR. Disease duration, prior surgery, and pre-surgical diabetes were not associated with circulating miRNAs. Levels of hsa-miR-29b-3p (P = 0.03), hsa-miR-148a-3p (P = 0.04) and hsa-miR-221-3p (P = 0.01) were lower in those with genetic risk factors. Levels of hsa-miR-148a-3p (P = 0.04) and hsa-miR-7-5p (P = 0.04) were elevated in toxic/metabolic disease. Participants with exocrine insufficiency had lower hsa-miR-29b-3p, hsa-miR-148a-3p, hsa-miR-320d, hsa-miR-221-3p (P < 0.01) and hsa-miR-375, hsa-miR-200c-3p, and hsa-miR-125b-5p (P < 0.05). Four miRNAs were associated with fasting C-peptide before TPIAT (hsa-miR-29b-3p, r = 0.18; hsa-miR-148a-3p, r = 0.21; hsa-miR-320d, r = 0.19; and hsa-miR-221-3p, r = 0.21; all P < 0.05), while hsa-miR-29b-3p was inversely associated with post-isolation islet equivalents/kg and islet number/kg (r = -0.20, P = 0.02). Also, hsa-miR-200c (r = 0.18, P = 0.03) and hsa-miR-221-3p (r = 0.19, P = 0.03) were associated with islet graft tissue volume. Further investigation is needed to determine the predictive potential of these miRNAs for assessing islet autotransplant outcomes.
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Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/fisiopatología , MicroARNs/metabolismo , Pancreatectomía/métodos , Trasplante Autólogo/métodos , Adulto , Femenino , Humanos , Masculino , Estudios ProspectivosRESUMEN
BACKGROUND: Despite ongoing advances in treatment, thousands of patients still die annually from complications due to hemorrhagic shock, a condition causing dramatic physiologic and metabolic changes as cells switch to anaerobic metabolism in response to oxygen deprivation. As the shift from aerobic to anaerobic metabolism occurs in the peripheral tissues during shock, the liver must increase production of endogenous glucose as well as process excess lactate produced in the periphery. This places the liver at the center of metabolic regulation in the body during hemorrhagic shock. Therefore, we hypothesized that liver tissue from pigs during an in vivo model of hemorrhagic shock (n = 6) would reflect resultant metabolic changes. MATERIALS AND METHODS: The in vivo model of shock consisted of 45 min of shock followed by 8 h of hypotensive resuscitation (80 mmHg) and subsequent normotensive resuscitation (90 mmHg) ending 48 h after the shock period. Control groups of pigs (n = 3) (1) shock with no resuscitation, and (2) only anesthesia and instrumentation, also were included. Metabolic changes within the liver after shock and during resuscitation were investigated using both proton ((1)H) and phosphorous ((31)P) nuclear magnetic resonance (NMR) spectroscopy. RESULTS: Concentrations of glycerylphosphorylcholine (GPC) and glycerylphosphorylethanolamine (GPE) were significantly lower at 8 h after shock, with recovery to baseline by 23 and 48 h after shock. Uridine diphosphate-glucose (UDP-glucose), and phosphoenolpyruvate (PEP) were elevated 23 h after shock. CONCLUSIONS: These results indicate that (1)H and (31)P NMR spectroscopy can be used to identify differences in liver metabolites in an in vivo model of hemorrhagic shock, indicating that metabolomic analysis can be used to elucidate biochemical events occurring during this complex disease process.
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Hígado/metabolismo , Metaboloma/fisiología , Choque Hemorrágico/metabolismo , Umbral Anaerobio/fisiología , Animales , Gluconeogénesis/fisiología , Glicerilfosforilcolina/metabolismo , Masculino , Resonancia Magnética Nuclear Biomolecular/métodos , Fosfatidiletanolaminas/metabolismo , Fosfoenolpiruvato/metabolismo , Isótopos de Fósforo , Protones , Resucitación , Choque Hemorrágico/terapia , Sus scrofa , Uridina Difosfato Glucosa/metabolismoRESUMEN
BACKGROUND: Hemorrhagic shock can lead to multiple organ failure and death. We have previously shown that noninvasive measurement of tissue oxygen saturation (StO(2)) has predictive value for outcomes in patients suffering hemorrhagic shock. Our study objectives were twofold: (1) to compare invasive and noninvasive measurements of local and systemic tissue hemoglobin oxygenation and (2) to compare the effects of various physiologic conditions seen in patients in hemorrhagic shock on tissue hemoglobin oxygenation. MATERIALS AND METHODS: We studied pigs in controlled conditions mimicking shock induced by one of the following: hypothermia, isovolemic hemodilution, or manipulations of vascular tone. We obtained both invasive and noninvasive measurements in a hind limb of StO(2), tissue hemoglobin index, femoral artery and venous flows, blood pressures, temperature, pH, pO(2), pCO(2), oxygen saturation, lactate, hemoglobin, and base excess. In all cases, we measured baseline values in both experimental and control hind limbs. RESULTS: We found that tissue hemoglobin oxygenation did not vary significantly over relevant physiologic temperatures. Under all physiologic conditions tested, we found supply-dependent oxygen consumption at oxygen levels less than 7 mL O(2)/min/kg. Similarly, we found that local oxygen delivery in animals subjected to varying degrees of isovolemic hemodilution or altered vascular tone was correlated with supply-dependent oxygen consumption, as measured by local noninvasive StO(2). CONCLUSIONS: Noninvasive StO(2) measurements are valid and durable over a wide range of physiologic conditions and correlate with invasively-measured oxygen delivery.
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Hemoglobinas/metabolismo , Consumo de Oxígeno , Oxígeno/sangre , Choque Hemorrágico/sangre , Anemia/sangre , Animales , Presión Sanguínea , Modelos Animales de Enfermedad , Hemodilución , Hipotermia/sangre , Masculino , Espectroscopía Infrarroja Corta , PorcinosRESUMEN
BACKGROUND: : Hypothermia after trauma is, in current medical practice, both avoided and aggressively treated. However, the effects of environmental hypothermia during early resuscitation after hemorrhagic shock have been only poorly characterized. METHODS: : The objective of our study was to compare normothermia versus mild and severe levels of hypothermia in a porcine model of hemorrhagic shock. In a prospective survival study, we anesthetized 19 juvenile male pigs (Yorkshire-Landrace, 15-25 kg) and caused them to hemorrhage until their systolic blood pressure was 45 mm Hg to 55 mm Hg for a duration of 45 minutes. Then, we randomized them into three groups (all of which underwent an 8-hour limited resuscitation period) as follows: normothermic (39 degrees C), mildly hypothermic (36 degrees C), and severely hypothermic (33 degrees C). We used ice packs to achieve surface cooling that mimicked environmental hypothermia. After 8 hours, we rewarmed the pigs and fully resuscitated them for 16 hours. We extubated the survivors and observed them for an additional 24 hours, before killing them. RESULTS: : Surface cooling resulted in significant reduction in core body temperature. The mortality rate was significantly higher in the normothermic group (60%) than in the two hypothermic groups combined (7%) (p = 0.015) or in the severely hypothermic group (0%) (p = 0.023). Hypothermic animals had significantly lower levels of creatinine kinase, lactate dehydrogenase, and lactate in addition to a lower base deficit after shock. However, severely hypothermic animals required greater volumes of colloid infusion and whole blood transfusion to maintain our target systolic blood pressure and hemoglobin levels when compared with normothermic animals. We saw a strong trend toward decreased oxygen consumption with hypothermia. CONCLUSIONS: : In our porcine model, we found that simulating mild and severe levels of environmental hypothermia during early resuscitation after hemorrhage was associated with a significantly decreased mortality rate. Furthermore, markers of cellular stress and organ dysfunction, including lactate levels and the base deficit, were lower in hypothermic animals. Decreasing oxygen consumption with hypothermia may, in part, explain the protective effects observed with hypothermia.
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Hipotermia/complicaciones , Hipotermia/terapia , Choque Hemorrágico/complicaciones , Choque Hemorrágico/terapia , Heridas y Lesiones/complicaciones , Heridas y Lesiones/terapia , Animales , Modelos Animales de Enfermedad , Fluidoterapia , Hipotermia/patología , Masculino , Resucitación , Recalentamiento , Choque Hemorrágico/patología , Análisis de Supervivencia , Porcinos , Heridas y Lesiones/patologíaRESUMEN
BACKGROUND: Complications of renal failure may prevent timely evacuation of injured soldiers. Conventional renal replacement therapy is not available in forward surgical units. METHODS: Records of in-theater improvised peritoneal dialysis (IPD) in level III hospitals or forward surgical units in Iraq or Afghanistan were reviewed to determine the following: cause of renal failure and associated injuries; type of dialysate, peritoneal access, and exchange technique; and patient outcome. These data were used to propose method for IPD using commonly available materials. RESULTS: IPD is described in four patients. Abdominal or chest drains were used with either improvised dextrose-electrolyte solution or commercial dialysate. Exchanges were successful, despite fresh surgical wounds including full laparotomy, removed excess fluid and restored acid and electrolyte balance, but did not correct azotemia. Open abdominal packing prevented continuation of IPD after 48 hours. Two patients fully recovered, one died, and one patient with a poor prognosis was lost to follow-up. CONCLUSION: IPD can be delivered effectively using readily available materials in forward surgical units and level III combat support hospitals.
Asunto(s)
Lesión Renal Aguda/terapia , Medicina Militar/métodos , Diálisis Peritoneal/métodos , Lesión Renal Aguda/etiología , Lesión Renal Aguda/mortalidad , Adulto , Campaña Afgana 2001- , Causalidad , Niño , Soluciones para Diálisis/química , Hospitales de Urgencia , Humanos , Guerra de Irak 2003-2011 , Masculino , Auditoría Médica , Medicina Militar/instrumentación , Medicina Militar/estadística & datos numéricos , Personal Militar , Traumatismo Múltiple/complicaciones , Quirófanos , Diálisis Peritoneal/instrumentación , Diálisis Peritoneal/estadística & datos numéricos , Atención Progresiva al Paciente , Transporte de Pacientes , Resultado del Tratamiento , Estados Unidos/epidemiología , Guerra , Heridas por Arma de Fuego/complicacionesRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0062792.].
RESUMEN
OBJECTIVE: To evaluate the relationship of early hypothermia to multiple organ failure and mortality in a prospectively-collected database of severely injured trauma patients. METHODS: This prospective observational study was performed at 7 level I trauma centers over a 16-month period. Severely injured trauma patients with signs of hypoperfusion (eg, base deficit, hypotension) and need for blood transfusion during their early hospital course were followed for 24 hours with near infrared spectroscopy-derived tissue oxygen saturation (StO2) and other variables for 28 days to evaluate outcomes including multiple organ dysfunction syndrome (MODS) and death. Early hypothermia was defined as the presence of a temperature <35°C [corrected] anytime within the first 6 hours of hospitalization. Comparisons between groups were made using the Wilcoxon Two-Sample test for continuous variables and either the Fisher exact or chi2 test for categorical variables. Multivariate logistic regression was utilized to understand the effect of hypothermia on outcome (MODS and mortality). RESULTS: Hypothermia was very common in this cohort of patients, present in 43% of patients enrolled (155/359). Hypothermic patients were 3 times more likely than normothermic patients to develop MODS (21% vs. 9%, P = 0.003). Hypothermic patients did not have an increased incidence of mortality (16% vs. 12%, P= 0.2826). Base deficit in hypothermic patients did not discriminate between patients who did or did not develop MODS (9.8 +/- 4.6 mEq/L vs. 9.4 +/- 4.4 mEq/L). In contrast, base deficit in hypothermic patients discriminated with respect to mortality (14.6 +/- 7.2 mEq/L versus 9.5 +/- 4.5 mEq/L; P 0.0021), but this effect was not observed in normothermic patients [corrected]. Significant predictors of MODS using multivariate analysis included minimum StO2 (P= 0.0014) and hypothermia (P = 0.0371). Predictors for mortality using multivariate analysis included minimum StO2 (P= 0.0021) and base deficit (P= 0.0454), but not hypothermia (P= 0.5289). Hypothermia remained a significant risk factor for MODS when systolic blood pressure, volume of fluid, and volume of blood infused were included in the multivariate model. CONCLUSION: Hypothermia is common in severely injured trauma patients (nearly half of patients in this series) and is a significant risk factor for MODS but not mortality. The predictive value of base deficit for development of MODS is blunted in the presence of hypothermia. A low StO2 value predicts MODS and mortality in trauma patients and is a durable measure in both normothermic and hypothermic patient groups.
Asunto(s)
Hipotermia/mortalidad , Insuficiencia Multiorgánica/mortalidad , Heridas y Lesiones/mortalidad , Adulto , Femenino , Humanos , Hipotermia/etiología , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/etiología , Estudios Prospectivos , Factores de Riesgo , Centros Traumatológicos , Estados Unidos , Heridas y Lesiones/complicacionesRESUMEN
The history of adjunctive treatments for severe sepsis has been fraught with more failures than successes. To date, there have been few interventions that have been demonstrated to be efficacious by multiple large, well-designed, multicenter randomized clinical trials. However, recent research into treatment strategies using drotrecogin alfa (activated), effective blood glucose management, early goal-directed therapy, protocolization of care, and intensivist management has demonstrated positive results. Further research is being conducted to verify the success of these initial trials. This article summarizes some of the available adjunctive treatments for severe sepsis.