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1.
JAMA ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748417

RESUMO

A 36-year-old man with obesity and dyslipidemia presented with elevated liver enzymes following a liver transplant to treat acute-on-chronic liver failure due to alcohol-associated hepatitis. What would you do next?

2.
BMJ Open ; 13(9): e075172, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723108

RESUMO

BACKGROUND AND AIMS: Liver transplantation is a life-saving procedure for end-stage liver disease. However, post-transplant medication regimens are complex and non-adherence is common. Post-transplant medication non-adherence is associated with graft rejection, which can have long-term adverse consequences. Transplant centres are equipped with clinical staff that monitor patients post-transplant; however, digital health tools and proactive immunosuppression adherence monitoring has potential to improve outcomes. METHODS AND ANALYSIS: This is a patient-randomised prospective clinical trial at three transplant centres in the Northeast, Midwest and South to investigate the effects of a remotely administered adherence programme compared with usual care. The programme monitors potential non-adherence largely levering text message prompts and phenotypes the nature of the non-adhere as cognitive, psychological, medical, social or economic. Additional reminders for medications, clinical appointments and routine self-management support are incorporated to promote adherence to the entire medical regimen. The primary study outcome is medication adherence via 24-hour recall; secondary outcomes include additional medication adherence (ASK-12 self-reported scale, regimen knowledge scales, tacrolimus values), quality of life, functional health status and clinical outcomes (eg, days hospitalised). Study implementation, acceptability, feasibility, costs and potential cost-effectiveness will also be evaluated. ETHICS AND DISSEMINATION: The University of Pennsylvania Review Board has approved the study as the single IRB of record (protocol # 849575, V.1.4). Results will be published in peer-reviewed journals and summaries will be provided to study funders. TRIAL REGISTRATION NUMBER: NCT05260268.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Humanos , Estudos Prospectivos , Qualidade de Vida , Cooperação e Adesão ao Tratamento
3.
Sci Rep ; 13(1): 4537, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941315

RESUMO

Sudden cardiac arrest (SCA) is a leading cause of mortality worldwide. The SCA-to-resuscitation interval is a key determinant of patient outcomes, highlighting the clinical need for reliable and timely detection of SCA. Near-infrared spectroscopy (NIRS), a non-invasive optical technique, may have utility for this application. We investigated transcutaneous NIRS as a method to detect pentobarbital-induced changes during cardiac arrest in eight Yucatan miniature pigs. NIRS measurements during cardiac arrest were compared to invasively acquired carotid blood pressure and partial oxygen pressure (PO2) of spinal cord tissues. We observed statistically significant decreases in mean arterial pressure (MAP) 64.68 mmHg ± 13.08, p < 0.0001), spinal cord PO2 (38.16 mmHg ± 20.04, p = 0.0028), and NIRS-derived tissue oxygen saturation (TSI%) (14.50% ± 3.80, p < 0.0001) from baseline to 5 min after pentobarbital administration. Euthanasia-to-first change in hemodynamics for MAP and TSI (%) were similar [MAP (10.43 ± 4.73 s) vs TSI (%) (12.04 ± 1.85 s), p = 0.3714]. No significant difference was detected between NIRS and blood pressure-derived pulse rates during baseline periods (p > 0.99) and following pentobarbital administration (p = 0.97). Transcutaneous NIRS demonstrated the potential to identify rapid hemodynamic changes due to cardiac arrest in periods similar to invasive indices. We conclude that transcutaneous NIRS monitoring may present a novel, non-invasive approach for SCA detection, which warrants further investigation.


Assuntos
Parada Cardíaca , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Suínos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Pentobarbital , Parada Cardíaca/diagnóstico , Medula Espinal , Modelos Animais , Morte Súbita Cardíaca , Oxigênio
4.
Am J Transplant ; 23(3): 437-439, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36695683

RESUMO

A 62-year-old received orthotopic liver transplantation. Three weeks later, thrombotic microangiopathy developed. Testing revealed thrombotic thrombocytopenic purpura (TTP) characterized by low ADAMTS13 (A Disintegrin-like Metallopeptidase with ThromboSpondin type 1 motif 13) activity and no inhibitor of ADAMTS13 protein. Retrospective attainment of donor records revealed a TTP diagnosis, presumably hereditary TTP (hTTP), as an ADAMTS13 protein inhibitor was not mentioned. As the grafted liver does not produce ADAMTS13 protein, the recipient now functionally has hTTP and will likely need plasma transfusions indefinitely. While hTTP is extremely rare, it should be considered a contraindication to liver donation outside of exceptional circumstances. If a potential liver donor has TTP listed on medical history, attempts should be made to determine whether it is autoimmune or hereditary. An accurate medical history is critical as it is the only reliable way to identify hTTP, as outside of acute exacerbations of TTP, donors with hTTP can have normal laboratory values, including normal hemoglobin, platelets, and renal function.


Assuntos
Transplante de Fígado , Púrpura Trombocitopênica Trombótica , Microangiopatias Trombóticas , Humanos , Pessoa de Meia-Idade , Púrpura Trombocitopênica Trombótica/diagnóstico , Proteína ADAMTS13 , Estudos Retrospectivos
6.
BMC Gastroenterol ; 22(1): 410, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064324

RESUMO

BACKGROUND: Malignancy-related ascites accounts for approximately 10% of causes of ascites. Our AIM was to characterize the ascites fluid and correlate clinical outcomes in those with extrahepatic malignancy and ascites. METHODS: 241 subjects with extrahepatic solid tumors and ascites were reviewed from 1/1/2000 to 12/31/2019, 119 without liver metastasis and 122 with liver metastasis. RESULTS: Ascites fluid consistent with peritoneal carcinomatosis (PC) was most common, 150/241 (62%), followed by fluid reflecting the presence of portal hypertension (PH), 69/241 (29%). 22/241 (9%) had low SAAG and low ascites fluid total protein, with evidence of PC on cytology and or imaging in 20/22. Lung cancer was the most common malignancy in subjects with ascites due to PC at 36/150 (24%), pancreatic cancer was the most common in subjects with ascites with features of PH at 16/69 (23%). Chemotherapy or immunotherapy alone was the most common management approach. Significantly higher 5-year, 3-year and 1-year mortality rate were noted in subjects with evidence of PC on cytology/imaging versus subjects with no evidence of PC, and in subjects with liver metastasis compared to subjects without liver metastasis. Subjects with pancreatic cancer and evidence of PC on cytology/imaging had higher 1 and 5-year mortality rates compared to subjects without PC. CONCLUSIONS: Ascites in solid tumor malignancy is most commonly due to PC. We also observed ascites fluid with characteristics of PH in 29% of subjects. Higher mortality rates in subjects with peritoneal carcinomatosis and liver metastasis were noted. These findings may help inform prognosis and treatment strategies.


Assuntos
Hipertensão Portal , Neoplasias Hepáticas , Neoplasias Pancreáticas , Neoplasias Peritoneais , Ascite/etiologia , Líquido Ascítico/química , Humanos , Hipertensão Portal/complicações , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/complicações , Neoplasias Peritoneais/secundário , Neoplasias Pancreáticas
7.
Hepatol Commun ; 6(11): 3052-3061, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36004713

RESUMO

Chronic hepatitis B virus (HBV) infection is the leading risk factor for hepatocellular carcinoma (HCC). The aim of this study was to explore the incidence of HCC in a cohort of subjects with HBV and correlate with HBV treatment current guidance. We identified 2846 subjects with HBV over the study period. HCC was diagnosed in 386 of 2846 (14%) subjects; 209 of 386 (54%) were on nucleos(t)ide analogue (NA) therapy at time of HCC diagnosis, and 177 of 386 (46%) were not on NA therapy. Of the 177 subjects not on NAs who developed HCC during follow-up, 153 of 177 (86%) had cirrhosis. Within the 177 subjects not on NAs, 158 of 177 (89%) had undetectable HBV DNA, 10 of 177 (6%) had detectable HBV DNA < 2000 IU/L, and 9 of 177 (5%) had HBV DNA > 2000 IU/L. Of those with cirrhosis and undetectable HBV DNA, 115 of 141 had compensated cirrhosis, and 26 of 141 had decompensated cirrhosis. Significant predictors of HCC on time to event analysis included cirrhosis (hazard ratio [HR] 10, 95% confidence interval [CI] 5.8-17.5; p < 0.001), alanine aminotransferase level (HR 1.004, 95% CI 1.002-1.006; p < 0.001), age (HR 1.04, 95% CI 1.03-1.06; p < 0.001), (HR 1.9, 95% CI 1.2-3.1; p 0.007), and nonalcoholic fatty liver disease (HR 1.7, 95% CI 1.1-2.8; p 0.02). Kaplan-Meier analysis demonstrated the cumulative incidence of HCC in subjects with compensated cirrhosis receiving NA therapy was significantly lower compared to subjects with compensated cirrhosis outside current HBV treatment practice guidance (undetectable HBV DNA) (32% vs. 51%; p < 0.001). Conclusion: Those with untreated compensated cirrhosis with undetectable HBV DNA who do not meet current guidance for treatment had higher rates of HCC than those with compensated cirrhosis and suppressed HBV DNA by NA therapy. This study highlights the need for earlier diagnosis and treatment of HBV.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Hepatite B Crônica/complicações , Carcinoma Hepatocelular/epidemiologia , Incidência , DNA Viral/uso terapêutico , Neoplasias Hepáticas/epidemiologia , Alanina Transaminase/uso terapêutico , Antivirais/uso terapêutico , Cirrose Hepática/tratamento farmacológico
8.
J Biomed Opt ; 27(7)2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35879816

RESUMO

SIGNIFICANCE: Pulse oximetry is widely used in clinical practice to monitor changes in arterial oxygen saturation (SpO2). However, decreases in SpO2 can be delayed relative to the actual clinical event, and near-infrared spectroscopy (NIRS) may detect alterations in oxygenation earlier than pulse oximetry, as shown in previous cerebral oxygenation monitoring studies. AIM: We aim to compare the response of transcutaneous muscle NIRS measures of the tissue saturation index with pulse oximetry SpO2 during hypoxia. APPROACH: Episodes of acute hypoxia were induced in nine anesthetized Yucatan miniature pigs. A standard pulse oximeter was attached to the ear of the animal, and a transcutaneous NIRS sensor was placed on the hind limb muscle. Hypoxia was induced by detaching the ventilator from the animal and reattaching it once the pulse oximeter reported 70% SpO2. RESULTS: Twenty-four episodes of acute hypoxia were analyzed. Upon the start of hypoxia, the transcutaneous NIRS measures changed in 5.3 ± 0.4 s, whereas the pulse oximetry measures changed in 14.9 ± 1.0 s (p < 0.0001). CONCLUSIONS: Transcutaneous muscle NIRS can detect the effects of hypoxia significantly sooner than pulse oximetry in the Yucatan miniature pig. A transcutaneous NIRS sensor may be used as an earlier detector of oxygen saturation changes in the clinical setting than the standard pulse oximeter.


Assuntos
Oximetria , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Hipóxia/diagnóstico por imagem , Oximetria/métodos , Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Suínos , Porco Miniatura
9.
Liver Transpl ; : 331-339, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37160065
10.
Clin Exp Gastroenterol ; 14: 457-465, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34819740

RESUMO

Nonalcoholic fatty liver disease and chronic kidney disease are both chronic conditions with rapidly increasing prevalence and incidence worldwide that have led to a significant burden on health-care systems. The association between these two disease entities is partly attributed to shared cardiometabolic comorbidities including diabetes, hypertension, obesity, and metabolic syndrome. However, independent of these overlapping risks, there are increased rates and more severe CKD in NAFLD patients. Conversely, more progressive NAFLD is seen with advanced stages of kidney injury. In addition to overlapping risk factors, shared pathogenic mechanisms suggest these two disease entities may resemble different manifestations of a single underlying disease process.

11.
J Hepatol ; 75(6): 1284-1291, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34380057

RESUMO

BACKGROUND & AIMS: Recently, international experts proposed redefining non-alcoholic fatty liver disease (NAFLD) as metabolic dysfunction-associated fatty liver disease (MAFLD), based on modified criteria. It is suspected that outcomes such as mortality may differ for these clinical entities. We studied the impact of MAFLD and NAFLD on all-cause and cause-specific mortality in US adults. METHODS: We analyzed data from 7,761 participants in the Third National Health and Nutrition Examination Survey and their linked mortality through 2015. NAFLD was diagnosed by ultrasonographic evidence of hepatic steatosis without other known liver diseases. MAFLD was defined based on the criteria proposed by an international expert panel. The Cox proportional hazard model was used to study all-cause mortality and cause-specific mortality between MAFLD and NAFLD, with adjustments for known risk factors. RESULTS: During a median follow-up of 23 years, individuals with MAFLD had a 17% higher risk of all-cause mortality (hazard ratio [HR] 1.17; 95% CI 1.04-1.32). Furthermore, MAFLD was associated with a higher risk of cardiovascular mortality. NAFLD per se did not increase the risk of all-cause mortality. Individuals who met both definitions had a higher risk of all-cause mortality (HR 1.13, 95% CI 1.00-1.26), while individuals who met the definition for MAFLD but not NAFLD had a 1.7-fold higher risk of all-cause mortality (HR 1.66, 95% CI 1.19-2.32). Estimates for all-cause mortality were higher for those with advanced fibrosis and MAFLD than for those with advanced fibrosis and NAFLD. CONCLUSIONS: In this US population-based study, MAFLD was associated with an increased risk of all-cause mortality, while NAFLD demonstrated no association with all-cause mortality after adjusting for metabolic risk factors. LAY SUMMARY: Our findings provide further support for the idea that non-alcoholic fatty liver disease (NAFLD) is a part of a broader multi-system disease that also includes obesity, diabetes, high blood pressure, and high cholesterol. Therefore, re-defining NAFLD as metabolic dysfunction-associated fatty liver disease (MAFLD) may help improve our understanding of predictors that increase the risk of death.


Assuntos
Fígado Gorduroso/etiologia , Doenças Metabólicas/complicações , Mortalidade/tendências , Adulto , Índice de Massa Corporal , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/mortalidade , Feminino , Humanos , Masculino , Doenças Metabólicas/epidemiologia , Doenças Metabólicas/mortalidade , Fatores de Risco , Estados Unidos/epidemiologia
12.
Cureus ; 13(6): e15403, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34249551

RESUMO

Background Bacterial translocation plays a pivotal role in the natural course of cirrhosis and its complications. Serum-derived bovine immunoglobulin (SBI) is an oral medical food that has been shown to both reduce inflammation in the intestines and neutralize bacteria. It represents a unique intervention that has not been studied in this population. Methodology We conducted a prospective open-label trial with an eight-week treatment phase of SBI. Individuals were assessed using lactulose breath testing, serum markers for enterocyte damage and bacterial translocation, and the Chronic Liver Disease Questionnaire (CLDQ) prior to and after completion of the treatment phase. Results We evaluated nine patients with a diagnosis of decompensated cirrhosis with ascites. Subjects had a mean Model for End-Stage Liver Disease (MELD) score of 11.6 ± 3.0 and were not taking lactulose or antibiotics. All subjects tolerated SBI well with no significant adverse events or changes to any of the six domains of the CLDQ. Laboratory tests including liver tests and MELD score remained stable over the course of treatment. There were no significant changes in the rates of small intestinal bacterial overgrowth (55.6% vs 55.6%, p = 1.00) or serum levels of lipopolysaccharide-binding protein, intestinal fatty acid-binding protein, or soluble CD14 (p-values 0.883, 0.765, and 0.748, respectively) when comparing values prior to and immediately after treatment. Conclusions No adverse events or significant changes to the quality of life were detected while on treatment. There were no statistically significant differences in our outcomes when comparing individuals before and after treatment in this small prospective proof-of-concept pilot study. Further prospective randomized studies could be beneficial.

13.
Hepatol Commun ; 5(3): 516-525, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33681683

RESUMO

Liver transplantation (LT) is definitive treatment for end-stage liver disease. This study evaluated factors predicting successful evaluation in patients transferred for urgent inpatient LT evaluation. Eighty-two patients with cirrhosis were transferred for urgent LT evaluation from January 2016 to December 2018. Alcohol-associated liver disease was the common etiology of liver disease (42/82). Of these 82 patients, 35 (43%) were declined for LT, 27 (33%) were wait-listed for LT, 5 (6%) improved, and 15 (18%) died. Psychosocial factors were the most common reasons for being declined for LT (49%). Predictors for listing and receiving LT on multivariate analysis included Hispanic race (odds ratio [OR], 1.89; P = 0.003), Asian race (OR, 1.52; P = 0.02), non-Hispanic ethnicity (OR, 1.49; P = 0.04), hyponatremia (OR, 1.38; P = 0.04), serum albumin (OR, 1.13; P = 0.01), and Model for End-Stage Liver Disease (MELD)-Na (OR, 1.02; P = 0.003). Public insurance (i.e., Medicaid) was a predictor of not being listed for LT on multivariate analysis (OR, 0.77; P = 0.02). Excluding patients declined for psychosocial reasons, predictors of being declined for LT on multivariate analysis included Chronic Liver Failure Consortium (CLIF-C) score >51.5 (OR, 1.26; P = 0.03), acute-on-chronic liver failure (ACLF) grade 3 (OR, 1.41; P = 0.01), hepatorenal syndrome (HRS) (OR, 1.38; P = 0.01), and respiratory failure (OR, 1.51; P = 0.01). Predictors of 3-month mortality included CLIF-C score >51.5 (hazard ratio [HR], 2.52; P = 0.04) and intensive care unit (HR, 8.25; P < 0.001). Conclusion: MELD-Na, albumin, hyponatremia, ACLF grade 3, HRS, respiratory failure, public insurance, Hispanic race, Asian race, and non-Hispanic ethnicity predicted liver transplant outcome. Lack of psychosocial support was a major reason for being declined for LT. The CLIF-C score predicted being declined for LT and mortality.


Assuntos
Doença Hepática Terminal/cirurgia , Transplante de Fígado/estatística & dados numéricos , Seleção de Pacientes , Encaminhamento e Consulta/estatística & dados numéricos , Índice de Gravidade de Doença , Idoso , Doença Hepática Terminal/psicologia , Feminino , Humanos , Transplante de Fígado/psicologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Psicologia , Estudos Retrospectivos , Estados Unidos , Listas de Espera
14.
Clin Gastroenterol Hepatol ; 19(6): 1240-1247.e5, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32683103

RESUMO

BACKGROUND & AIMS: The association between physical activity (PA) and all-cause and cause-specific mortality from nonalcoholic fatty liver disease (NAFLD) requires investigation. We studied whether PA, measured by accelerometer, is associated with all-cause and cause-specific mortality among individuals with NAFLD. METHODS: We performed a longitudinal analysis using the 2003 to 2006 US National Health and Nutrition Examination Survey data of adults (age, ≥20 y) and collecting mortality data through December 2015. NAFLD was defined based on the hepatic steatosis index or US fatty liver index scores, in the absence of other causes of chronic liver disease. PA was measured from participants who wore accelerometers 10 h/d for a minimum of 4 days over a 7-day period and were classified as total PA, moderate to vigorous PA (MVPA), and sedentary behavior. RESULTS: Over an average follow-up period of 10.6 years, increasing the duration of total PA was associated with a reduced risk of death, from any cause, in an age- and sex-adjusted model (hazard ratio [HR], 0.52; 95% CI, 0.32-0.86 for highest quartile vs lowest quartile; P for trend = .001) and multivariable model (HR, 0.46; 95% CI, 0.28-0.75; P for trend < .001) among individuals with NAFLD. Increasing the duration of MVPA was associated with a lower risk of death from any cause in individuals with NAFLD. Furthermore, longer total PA was associated with a lower risk for cardiovascular disease-related death in individuals with NAFLD (HR, 0.28; 95% CI, 0.08-0.98 for highest quartile vs lowest quartile; P for trend = .007). We did not find this association for cancer-related mortality in individuals with NAFLD. Increasing the duration of sedentary behavior did not affect all-cause or cause-specific mortality in individuals with NAFLD. CONCLUSIONS: Longer total PA and MVPA, measured by accelerometers over a 7-day period, are associated with lower all-cause and cardiovascular mortality in individuals with NAFLD.


Assuntos
Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Adulto , Exercício Físico , Humanos , Inquéritos Nutricionais , Comportamento Sedentário
15.
Clin Liver Dis ; 24(3): 405-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32620280

RESUMO

Viral hepatitis can cause a wide spectrum of clinical presentations from a benign form with minimal or no symptoms to acute liver failure or death. Hepatitis D coinfection and superinfection have distinct clinical courses, with the latter more likely leading to chronic infection. Management of chronic hepatitis D virus is individualized because of the paucity of treatment options and significant side effect profile of currently available treatments. Sporadic cases of hepatitis E caused by contaminated meats are becoming increasingly prevalent in immunocompromised hosts. Human herpesviruses are an important cause of disease also in immunocompromised individuals.


Assuntos
Hepatite D/diagnóstico , Hepatite D/tratamento farmacológico , Hepatite E/diagnóstico , Coinfecção/diagnóstico , Infecções por Citomegalovirus/complicações , Infecções por Vírus Epstein-Barr/complicações , Hepatite B/complicações , Hepatite D/complicações , Hepatite E/terapia , Herpes Simples/complicações , Humanos , Hospedeiro Imunocomprometido , Hepatopatias/virologia , Fatores de Risco , Infecção pelo Vírus da Varicela-Zoster/complicações
16.
J Neurotrauma ; 37(21): 2292-2301, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32689879

RESUMO

One of the only currently available treatment options to potentially improve neurological recovery after acute spinal cord injury (SCI) is augmentation of mean arterial blood pressure (MAP) to promote blood flow and oxygen delivery to the injured cord. However, to optimize such hemodynamic management, clinicians require a method to monitor the physiological effects of these MAP alterations within the injured cord. Therefore, we investigated the feasibility and effectiveness of using a novel optical sensor, based on near-infrared spectroscopy (NIRS), to monitor real-time spinal cord oxygenation and hemodynamics during the first 7 days post-injury in a porcine model of acute SCI. Six Yucatan miniature pigs underwent a T10 vertebral level contusion-compression injury. Spinal cord oxygenation and hemodynamics were continuously monitored by a minimally invasive custom-made NIRS sensor, and by invasive intraparenchymal (IP) probes to validate the NIRS measures. Episodes of MAP alteration and hypoxia were performed acutely after injury, and at 2 and 7 days post-injury to simulate the types of hemodynamic changes SCI patients experience after injury. The NIRS sensor demonstrated the ability to provide oxygenation and hemodynamic measurements over the 7-day post-SCI period. NIRS measures showed statistically significant correlations with each of the invasive IP measures and MAP changes during episodes of MAP alteration and hypoxia throughout the first week post-injury (p < 0.05). These results indicate that this novel NIRS system can monitor real-time changes in spinal cord oxygenation and hemodynamics over the first 7 days post-injury, and has the ability to detect local tissue changes that are reflective of systemic hemodynamic changes.


Assuntos
Hemodinâmica/fisiologia , Monitorização Neurofisiológica/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/irrigação sanguínea , Animais , Modelos Animais de Doenças , Feminino , Monitorização Neurofisiológica/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Medula Espinal/fisiopatologia , Suínos , Porco Miniatura
17.
Clin Liver Dis (Hoboken) ; 15(4): 141-143, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32395239

RESUMO

http://aasldpubs.onlinelibrary.wiley.com/hub/journal/10.1002/(ISSN)2046-2484/video/15-4-reading-cheung a video presentation of this article - http://aasldpubs.onlinelibrary.wiley.com/hub/journal/10.1002/(ISSN)2046-2484/video/15-4-interview-cheung an interview with the author https://www.wileyhealthlearning.com/Activity/7088571/disclaimerspopup.aspx questions and earn CME.

18.
J Neurotrauma ; 37(15): 1696-1707, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32233727

RESUMO

Current practice guidelines for acute spinal cord injury (SCI) recommend augmenting mean arterial blood pressure (MAP) for the first 7 days post-injury. After SCI, the cord may be compressed by the bone/ligaments of the spinal column, limiting regional spinal cord blood flow. Following surgical decompression, blood flow may be restored, and can potentially promote a "reperfusion" injury. The effects of MAP augmentation on the injured cord during the compressed and decompressed conditions have not been previously characterized. Here, we used our porcine model of SCI to examine the impact of MAP augmentation on blood flow, oxygenation, hydrostatic pressure, metabolism, and intraparenchymal (IP) hemorrhage within the compressed and then subsequently decompressed spinal cord. Yucatan mini-pigs underwent a T10 contusion injury followed by 2 h of sustained compression. MAP augmentation of ∼20 mm Hg was achieved with norepinephrine (NE). Animals received MAP augmentation either during the period of cord compression (CP), after decompression (DCP), or during both periods (CP-DCP). Probes to monitor spinal cord blood flow (SCBF), oxygenation, pressure, and metabolic responses were inserted into the cord parenchyma adjacent to the injury site to measure these responses. The cord was harvested for histological evaluation. MAP augmentation increased SCBF and oxygenation in all groups. In the CP-DCP group, spinal cord pressure steadily increased and histological analysis showed significantly increased hemorrhage in the spinal cord at and near the injury site. MAP augmentation with vasopressors may improve blood flow and reduce ischemia in the injured cord but may also induce undesirable increases in IP pressure and hemorrhage.


Assuntos
Modelos Animais de Doenças , Hemorragia/metabolismo , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/irrigação sanguínea , Medula Espinal/metabolismo , Vasoconstritores/administração & dosagem , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Feminino , Hemorragia/induzido quimicamente , Hemorragia/patologia , Medula Espinal/efeitos dos fármacos , Traumatismos da Medula Espinal/patologia , Suínos , Porco Miniatura , Vértebras Torácicas/lesões , Vasoconstritores/toxicidade
19.
Proc Natl Acad Sci U S A ; 117(38): 23286-23291, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-31213548

RESUMO

Painful or threatening experiences trigger escape responses that are guided by nociceptive neuronal circuitry. Although some components of this circuitry are known and conserved across animals, how this circuitry is regulated at the genetic and developmental levels is mostly unknown. To escape noxious stimuli, such as parasitoid wasp attacks, Drosophila melanogaster larvae generate a curling and rolling response. Rover and sitter allelic variants of the Drosophila foraging (for) gene differ in parasitoid wasp susceptibility, suggesting a link between for and nociception. By optogenetically activating cells associated with each of for's promoters (pr1-pr4), we show that pr1 cells regulate larval escape behavior. In accordance with rover and sitter differences in parasitoid wasp susceptibility, we found that rovers have higher pr1 expression and increased sensitivity to nociception relative to sitters. The for null mutants display impaired responses to thermal nociception, which are rescued by restoring for expression in pr1 cells. Conversely, knockdown of for in pr1 cells phenocopies the for null mutant. To gain insight into the circuitry underlying this response, we used an intersectional approach and activity-dependent GFP reconstitution across synaptic partners (GRASP) to show that pr1 cells in the ventral nerve cord (VNC) are required for the nociceptive response, and that multidendritic sensory nociceptive neurons synapse onto pr1 neurons in the VNC. Finally, we show that activation of the pr1 circuit during development suppresses the escape response. Our data demonstrate a role of for in larval nociceptive behavior. This function is specific to for pr1 neurons in the VNC, guiding a developmentally plastic escape response circuit.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Reação de Fuga , Larva/crescimento & desenvolvimento , Nociceptores/metabolismo , Animais , Proteínas Quinases Dependentes de GMP Cíclico/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Temperatura Alta , Larva/genética , Larva/fisiologia , Plasticidade Neuronal , Nociceptividade , Regiões Promotoras Genéticas , Vespas/fisiologia
20.
J Physiol ; 598(5): 929-942, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31876952

RESUMO

KEY POINTS: We have developed a novel porcine model of high-thoracic midline contusion spinal cord injury (SCI) at the T2 spinal level. We describe this model and the ensuing cardiovascular and neurohormonal responses, and demonstrate the model is efficacious for studying clinically relevant cardiovascular dysfunction post-SCI. We demonstrate that the high-thoracic SCI model, but not a low-thoracic SCI model, induces persistent hypotension along with a gradual reduction in plasma noradrenaline and increases in plasma aldosterone and angiotensin II. We additionally conducted a proof-of-concept long-term (12 weeks) survival study in animals with T2 contusion SCI demonstrating the potential utility of this model for not only acute experimentation but also long-term drug studies prior to translation to the clinic. ABSTRACT: Cardiovascular disease is a leading cause of morbidity and mortality in the spinal cord injury (SCI) population, especially in those with high-thoracic or cervical SCI. With this in mind, we aimed to develop a large animal (porcine) model of high-thoracic (T2 level) contusion SCI and compare the haemodynamic and neurohormonal responses of this injury against a low-thoracic (T10 level) model. Ten Yorkshire pigs were randomly subjected to 20 cm weight drop contusion SCI at either the T2 or the T10 spinal level. Systolic blood pressure (SBP), mean arterial pressure (MAP) and heart rate (HR) were continuously monitored until 4 h post-SCI. Plasma noradrenaline (NA), aldosterone and angiotensin II (ANGII) were measured pre-SCI and at 30, 60, 120 and 240 min post-SCI. Additionally, two Yucatan pigs were subjected to T2-SCI and survived up to 12 weeks post-injury to demonstrate the efficacy of this model for long-term survival studies. Immediately after T2-SCI, SBP, MAP and HR increased (P < 0.0001). Between decompression (5 min post-SCI) and 30 min post-decompression in T2-SCI, SBP and MAP were lower than pre-SCI (P < 0.038). At 3 and 4 h after T2-SCI, SBP remained lower than pre-SCI (P = 0.048). After T10-SCI, haemodynamic indices remained largely unaffected. Plasma NA was lower in T2- vs. T10-SCI post-SCI, whilst aldosterone and ANGII were higher. Both chronically injured pigs demonstrated a vast reduction in SBP at 12 weeks post-SCI. Our model of T2-SCI causes a rapid and sustained alteration in neurohormonal control and cardiovascular function, which does not occur in the T10 model.


Assuntos
Sistema Cardiovascular , Traumatismos da Medula Espinal , Animais , Pressão Sanguínea , Modelos Animais de Doenças , Hemodinâmica , Medula Espinal , Suínos
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