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1.
Ann Surg ; 279(1): 104-111, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37522174

RESUMO

OBJECTIVE: To evaluate long-term oncologic outcomes of patients post-living donor liver transplantation (LDLT) within and outside standard transplantation selection criteria and the added value of the incorporation of the New York-California (NYCA) score. BACKGROUND: LDLT offers an opportunity to decrease the liver transplantation waitlist, reduce waitlist mortality, and expand selection criteria for patients with hepatocellular carcinoma (HCC). METHODS: Primary adult LDLT recipients between October 1999 and August 2019 were identified from a multicenter cohort of 12 North American centers. Posttransplantation and recurrence-free survival were evaluated using the Kaplan-Meier method. RESULTS: Three hundred sixty LDLTs were identified. Patients within Milan criteria (MC) at transplantation had a 1, 5, and 10-year posttransplantation survival of 90.9%, 78.5%, and 64.1% versus outside MC 90.4%, 68.6%, and 57.7% ( P = 0.20), respectively. For patients within the University of California San Francisco (UCSF) criteria, respective posttransplantation survival was 90.6%, 77.8%, and 65.0%, versus outside UCSF 92.1%, 63.8%, and 45.8% ( P = 0.08). Fifty-three (83%) patients classified as outside MC at transplantation would have been classified as either low or acceptable risk with the NYCA score. These patients had a 5-year overall survival of 72.2%. Similarly, 28(80%) patients classified as outside UCSF at transplantation would have been classified as a low or acceptable risk with a 5-year overall survival of 65.3%. CONCLUSIONS: Long-term survival is excellent for patients with HCC undergoing LDLT within and outside selection criteria, exceeding the minimum recommended 5-year rate of 60% proposed by consensus guidelines. The NYCA categorization offers insight into identifying a substantial proportion of patients with HCC outside the MC and the UCSF criteria who still achieve similar post-LDLT outcomes as patients within the criteria.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Adulto , Humanos , Transplante de Fígado/métodos , Doadores Vivos , Recidiva Local de Neoplasia/etiologia , Seleção de Pacientes , América do Norte , Estudos Retrospectivos , Resultado do Tratamento
2.
Transplantation ; 107(9): 1991-1998, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36959124

RESUMO

BACKGROUND: The ability of vibration controlled transient elastography (VCTE) to reliably exclude significant steatosis in living donor candidates could obviate the need for invasive liver biopsies, expedite the donor approval process, and reduce recipient wait time. We therefore aimed to determine whether VCTE controlled attenuation parameter (CAP) could be used to detect steatosis in potential living donors. METHODS: Living donor candidates who presented for evaluation between 2016 and 2019 underwent standard donor workup, VCTE, and liver biopsy if indicated. CAP scores were compared with MRI-Fat Fraction and, when available, histologic fat fraction from liver biopsy. Receiver operating characteristic curves were used to identify cutoffs with appropriate sensitivity and specificity for screening. Statistical analysis was conducted using R (version 3.6.0). RESULTS: Seventy-nine candidate living donors presented during the study period, of whom 71 were included in the final analysis and of whom 20 underwent liver biopsy. There was a positive correlation between MRI-Fat Fraction and CAP scores with an observed Spearman correlation coefficient of 0.424 ( P < 0.01). A CAP score of 271.5 dB/m or less was determined to have 89.8% sensitivity and 75% specificity for detecting <5% steatosis on MRI. The correlation between CAP and steatosis of available histologic samples had a Pearson correlation coefficient of 0.603 ( P = 0.005). A CAP cutoff of 276.0 dB/m demonstrated 66.7% sensitivity and 85.7% specificity for detecting <15% histopathologic steatosis and positive and negative predictive values of 71.5% and 82.7%, respectively. CONCLUSIONS: VCTE can be integrated into living donor evaluation to accurately screen for hepatic steatosis.


Assuntos
Técnicas de Imagem por Elasticidade , Fígado Gorduroso , Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica , Humanos , Transplante de Fígado/efeitos adversos , Doadores Vivos , Vibração , Fígado Gorduroso/patologia , Curva ROC , Biópsia , Fígado/diagnóstico por imagem , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia
3.
Oxf Med Case Reports ; 2021(11): omab113, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34858627

RESUMO

Wild-type ATTR cardiac amyloidosis (ATTRwt-CA) is not as rare as previously thought to be. Patients with infiltrative cardiac amyloidosis often present with right-sided heart failure (HF) symptomatology. Clinically significant liver disease and cirrhosis has not been reported in ATTRwt-CA. We present two cases of ATTRwt-CA with right-sided HF and abnormal liver function tests initially thought to be secondary to congestive hepatopathy but found to have rare and unrelated liver disease. These cases highlight the importance of developing a broad differential diagnosis and leveraging a multidisciplinary team approach in evaluating patients for unusual causes of cirrhosis/other chronic liver diseases when ATTR cardiac amyloidosis patients present with congestive hepatopathy.

4.
Transplantation ; 102(6): 953-960, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29369249

RESUMO

BACKGROUND: Despite high survival in pediatric living donor liver transplantation (LDLT), only 10% of liver transplants in children in the United States are from living donors, reflecting reluctance to embrace this approach. In addition to optimal timing and graft quality, LDLT may offer immunologic benefit because most donors are haploidentical parents. We sought to quantify the benefit of LDLT compared to deceased donor liver transplantation (DDLT) using granular clinical and immunologic outcomes over the long term. METHODS: A retrospective cohort of children (age <18 years) surviving 1 year or longer posttransplant was evaluated to determine the impact of donor type on graft survival and immunologic outcomes. RESULTS: Two hundred forty-one children (177 DDLT and 64 LDLT) were assessed. In multivariable analysis, LDLT was associated with a lower rate of acute cellular rejection (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.29-0.98; P = 0.04), a lower rate of chronic rejection (HR, 0.12; 95% CI, 0.03-0.56; P = 0.007), better graft survival on monotherapy immunosuppression at 3 years posttransplant (87.7% vs 46.7%; odds ratio, 7.41; 95% CI, 2.80-19.66; P < 0.001), and a lower rate of graft loss (HR, 0.29; 95% CI, 0.10-0.88; P = 0.03). Graft type was not an independent predictor of posttransplant mortality (LDLT HR, 0.57; 95% CI, 0.16-2.01; P = 0.38). Maternal graft LDLT was associated with a lower rate of acute cellular rejection (HR, 0.13; 95% CI, 0.03-0.64; P = 0.01) and posttransplant lymphoproliferative disorder (HR, 0.04; 95% CI, 0.004-0.44; P = 0.008) compared with paternal grafts. CONCLUSIONS: This study demonstrates the potential benefit of LDLT, particularly with maternal grafts, for pediatric liver transplant recipients on multiple clinical parameters over long-term follow-up.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Fígado/métodos , Doadores Vivos , Adolescente , Fatores Etários , Criança , Pré-Escolar , Pai , Feminino , Rejeição de Enxerto/imunologia , Histocompatibilidade , Humanos , Lactente , Transplante de Fígado/efeitos adversos , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/prevenção & controle , Masculino , Mães , Fatores de Proteção , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Transplante Haploidêntico , Resultado do Tratamento
5.
Liver Transpl ; 21(6): 768-73, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25789460

RESUMO

Living donor liver transplantation has failed to become a major means of transplantation in the United States, where <5% of the transplants are performed with living donors. At least 30% to 50% of the complications of donor hepatectomy appear to be related to abdominal wall trauma, including hernia, bowel obstruction, and chronic abdominal discomfort. We analyzed our experience with laparoscopically procured donor hepatectomy. We compared 22 full laparoscopic donor hepatectomies to 20 open/hybrid hepatectomies over an 11-year period. Donor and recipient demographics, complications, and graft and recipient outcomes were analyzed. All 22 laparoscopically procured liver allografts were transplanted successfully. The laparoscopically procured grafts took longer to procure (7 hours 58 minutes versus 6 hours 38 minutes; P < 0.001). The laparoscopically procured cases had lower blood loss (177.3 versus 3753 cc; P < 0.001), a shorter length of stay, and significantly reduced days off work (P = .01). The 1-year graft survival was not different (90% in the laparoscopic group and 85% in the open group; P = 0.70). The 1-year patient survival was not different (95% in the laparoscopic group and 85% in the open group; P = 0.32). There was a trend toward lower wound issues in the laparoscopic group, but this did not reach significance (the hybrid/open group had a 15% hernia rate versus 5% for the laparoscopic group). In experienced living donor centers, laparoscopic liver donation appears to be feasible for all pediatric recipients and some adult recipients. Outcomes for the recipients of laparoscopically procured grafts do not appear significantly different from outcomes with hybrid/open techniques.


Assuntos
Hepatectomia/métodos , Transplante de Fígado/estatística & dados numéricos , Doadores Vivos/estatística & dados numéricos , Adolescente , Adulto , Feminino , Hepatectomia/estatística & dados numéricos , Humanos , Laparoscopia , Tempo de Internação/estatística & dados numéricos , Masculino , Retorno ao Trabalho/estatística & dados numéricos , Adulto Jovem
6.
Liver Int ; 35(2): 510-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24905624

RESUMO

BACKGROUND & AIMS: Prevention of recurrent hepatitis C virus (HCV) following liver transplant (LT) with pre-LT antiviral therapy is limited by poor tolerability and efficacy. We aimed to evaluate the safety and efficacy of NS3/4A protease inhibitor (PI)-based triple therapy in patients awaiting LT. METHODS: Consecutive patients treated with triple therapy pre-LT from two centers were prospectively enrolled in an observational cohort. Overall 12 week sustained virological response (SVR12) was the primary outcome. Pre- and post-LT (pTVR) virological response rates and safety were secondary outcomes. RESULTS: Twenty-nine patients (mean age 57.9, 79% male, 66% prior non-responders) were treated with telaprevir (93%) or boceprevir-based (7%) triple therapy for a median (range) of 27 (3-50) weeks, including a pegylated-interferon and ribavirin lead-in in 18%. Median (range) MELD at treatment was 8 (6-16), 39% had hepatocellular carcinoma and all patients were Child-Turcotte-Pugh class A (62%) or B (38%). Twelve patients underwent LT, 75% with undetectable viral load. The overall SVR12 rate was 52%, including pre-LT SVR12 of 41% in patients who completed treatment and follow-up on the wait list and pTVR12 of 67% among transplanted patients. The pTVR12 rate was 89% among those patients with undetectable viral load at LT. Serious adverse events occurred in nine (31%) patients including one (3%) on-treatment death and eight (28%) hospitalizations. CONCLUSIONS: Overall SVR12 and pTVR12 rates are high among patients treated with PI-based triple therapy while awaiting LT, even in this difficult to treat population. However, caution is needed as early discontinuation and serious adverse events are common.


Assuntos
Hepatite C/tratamento farmacológico , Hepatite C/imunologia , Hepatite C/cirurgia , Transplante de Fígado , Inibidores de Proteases/uso terapêutico , RNA Viral/sangue , Quimioterapia Combinada , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Prolina/análogos & derivados , Prolina/uso terapêutico , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Estatísticas não Paramétricas , Carga Viral
7.
Liver Transpl ; 20(5): 536-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24493271

RESUMO

There is conflicting literature regarding the superiority of transarterial chemoembolization (TACE) versus bland transarterial embolization (TAE), and this has not been well studied before transplantation. Twenty-five TAE patients were matched in a 1:2 ratio with TACE patients by the initial radiographic tumor size and number in a retrospective, case-controlled study. The patients were otherwise treated according to the same protocols. The method of embolization was chosen on the basis of interventionalist practices at 2 sites within the program. Kaplan-Meier survival analyses at 1 and 3 years were the primary endpoints. There were no significant demographic differences between the groups. The mean adjusted Model for End-Stage Liver Disease scores at transplantation and waiting times were not significantly different between the TAE and TACE patients (MELD scores: 26 ± 3 versus 24 ± 3 points, P = 0.12; waiting times: 13 ± 8 versus 11 ± 10 months, P = 0.43). TAE patients (16%) were less likely than TACE patients (40%) to require 2 procedures (P = 0.04). Explant tumors were completely necrotic for 36% of the TAE patients and for 26% of the TACE patients. The 3-year overall survival rates were 78% for the TAE patients and 74% for the TACE patients (P = 0.66), and the 3-year recurrence-free survival rates were 72% for the TAE patients and 68% for the TACE patients (P = 0.67). On an intention-to-treat basis, there was no significant risk of wait-list dropout associated with TAE or TACE (P = 0.83). In conclusion, there were no significant differences in wait-list dropout or in overall or recurrence-free survival between HCC patients undergoing TAE and HCC patients undergoing TACE before transplantation.


Assuntos
Carcinoma Hepatocelular/cirurgia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Adulto , Idoso , Estudos de Casos e Controles , Intervalo Livre de Doença , Doença Hepática Terminal/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
8.
Hepatology ; 59(2): 496-504, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23904338

RESUMO

UNLABELLED: Substantial evidence has linked ionizing radiation exposure (RE) to oncogenesis. Patients evaluated for transplantation undergo extensive diagnostic imaging and have increased baseline cancer risk factors. The objective was to examine exposure in a cohort of patients undergoing evaluation and liver transplantation. Radiation exposure from all diagnostic examinations and procedures were retrospectively recorded. Radiation exposure is reported in mSv, a standardized measure of the detrimental biologic effect of radiation which allows for population-level comparisons. Seventy-four patients (69% male, mean 57 years) were evaluated, of which 13 of 35 subsequently listed patients were transplanted; an additional 18 previously evaluated patients were also transplanted during 2010. The most common indications were hepatitis C (55%) and hepatocellular carcinoma (HCC) (30%). The median observation period was 14 months. In all, 1,826 imaging examinations were performed, of which 408 (22%) involved considerable ionizing radiation and were the focus of investigation. Median annualized effective RE was 51 mSv (interquartile range [IQR]: 19,126), with 10% exposed to almost twice the amount of radiation recommended for a 5-year period. Patients with HCC received significantly (P < 0.00001) higher median annualized effective RE than patients without HCC, 137 mSv (IQR: 87,259) versus 32 mSv (IQR: 13,57), respectively. Computed tomography (CT) abdomen (23%) and chest (16%) accounted for the most common exposures, with CT abdomen accounting for 46% of overall cohort RE. CONCLUSION: Patients undergoing evaluation and liver transplantation at our center are exposed to very high levels of ionizing radiation. Although long-term effects in these patients are yet to be defined, the theoretical increased risk of malignancy must be given its due consideration. Routine use of nonradiation imaging and reconsideration of indications may be preferred and justified in this population.


Assuntos
Neoplasias Hepáticas/epidemiologia , Transplante de Fígado , Fígado/efeitos da radiação , Radiação Ionizante , Listas de Espera , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Diagnóstico por Imagem/efeitos adversos , Feminino , Seguimentos , Hepatite C/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Risco
9.
Semin Liver Dis ; 32(2): 177-85, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22760657

RESUMO

In the last three decades, the management of human immunodeficiency virus (HIV) has improved dramatically. The use of combination antiretroviral therapy (ART) has been successful at preventing death and the myriad infectious, malignant, and immune-mediated complications of HIV. Once considered to be a fatal disease, HIV is now considered by many to be a chronic disease; those affected may now live to experience complications of other coexistent diseases. Liver disease has been increasingly recognized as a leading cause of non-HIV/acquired immunodeficiency syndrome- (AIDS-) related morbidity and mortality in this population.Although liver transplantation offers the opportunity to prolong life, the transplant community has been slow to recognize the chronicity of HIV and potential for transplantation within this population. The experience with liver transplantation in HIV-positive patients is evolving and successful outcomes have been observed when specific criteria are used to select candidates.


Assuntos
Infecções por HIV/complicações , Hepatite Viral Humana/complicações , Transplante de Fígado/estatística & dados numéricos , Coinfecção , Contraindicações , Seleção do Doador , HIV , Hepatite Viral Humana/cirurgia , Humanos , Seleção de Pacientes , Índice de Gravidade de Doença
10.
Bioorg Med Chem Lett ; 18(19): 5280-4, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18783943

RESUMO

We describe here orally active and brain-penetrant cathepsin S selective inhibitors, which are virtually devoid of hERG K(+) channel affinity, yet exhibit nanomolar potency against cathepsin S and over 100-fold selectivity to cathepsin L. The new non-peptidic inhibitors are based on a 2-cyanopyrimidine scaffold bearing a spiro[3.5]non-6-yl-methyl amine at the 4-position. The brain-penetrating cathepsin S inhibitors demonstrate potential clinical utility for the treatment of multiple sclerosis and neuropathic pain.


Assuntos
Catepsinas/antagonistas & inibidores , Canais de Potássio Éter-A-Go-Go/metabolismo , Pirimidinas/síntese química , Pirimidinas/farmacologia , Administração Oral , Animais , Encéfalo/efeitos dos fármacos , Catepsina L , Técnicas de Química Combinatória , Cisteína Endopeptidases , Humanos , Masculino , Estrutura Molecular , Esclerose Múltipla/tratamento farmacológico , Dor/tratamento farmacológico , Pirimidinas/sangue , Pirimidinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
12.
J Med Chem ; 50(16): 3851-6, 2007 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-17630726

RESUMO

Selective activation of peripheral cannabinoid CB1 receptors has the potential to become a valuable therapy for chronic pain conditions as long as central nervous system effects are attenuated. A new class of cannabinoid ligands was rationally designed from known aminoalkylindole agonists and showed good binding and functional activities at human CB1 and CB2 receptors. This has led to the discovery of a novel CB1/CB2 dual agonist, naphthalen-1-yl-(4-pentyloxynaphthalen-1-yl)methanone (13), which displays good oral bioavailability, potent antihyperalgesic activity in animal models, and limited brain penetration.


Assuntos
Analgésicos/síntese química , Encéfalo/metabolismo , Hiperalgesia/tratamento farmacológico , Naftalenos/síntese química , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas , Administração Oral , Analgésicos/farmacocinética , Analgésicos/farmacologia , Animais , Disponibilidade Biológica , Cricetinae , Cricetulus , AMP Cíclico/biossíntese , Humanos , Técnicas In Vitro , Microssomos Hepáticos/metabolismo , Naftalenos/farmacocinética , Naftalenos/farmacologia , Ensaio Radioligante , Ratos , Ratos Wistar , Relação Estrutura-Atividade
13.
Pain ; 130(3): 225-234, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17250968

RESUMO

Using a gene expression analysis approach we found that the mRNA encoding the lysosomal cysteine protease cathepsin S (CatS) was up-regulated in rat dorsal root ganglia (DRG) following peripheral nerve injury. CatS protein was expressed in infiltrating macrophages in DRG and near the site of injury. At both sites CatS expression progressively increased from day 3 to day 14 after injury. In naïve rats, intraplantar injection of activated rat recombinant (rr) CatS (0.3, 1 microg/rat) induced a mechanical hyperalgesia that developed within half-an-hour, diminished by 3h and was absent after 24h. Activated rrCathepsin B (CatB) and non-activated rrCatS injected intraplantarly at the same or higher doses than activated rrCatS had no effect on rat nociceptive thresholds. In nerve-injured rats, mechanical hyperalgesia, but not allodynia, was significantly reversed for up to 3h by systemic administration of a non-brain penetrant, irreversible CatS inhibitor (LHVS, 3-30 mg/kg s.c.). Depletion of peripheral macrophages by intravenous injection of liposome encapsulate clodronate (1ml, 5 mg/ml) partially reduced established mechanical hyperalgesia but not allodynia, and abolished the anti-hyperalgesic effect of LHVS. Our results demonstrate a pro-nociceptive effect of CatS and indicate that endogenous CatS released by peripheral macrophages contributes to the maintenance of neuropathic hyperalgesia following nerve injury.


Assuntos
Catepsinas/genética , Catepsinas/metabolismo , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatologia , Nervo Isquiático/enzimologia , Animais , Catepsinas/farmacologia , Doença Crônica , Cisteína Endopeptidases/metabolismo , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Hiperalgesia/imunologia , Ligadura , Macrófagos/enzimologia , Masculino , Nociceptores/efeitos dos fármacos , Nociceptores/enzimologia , Nociceptores/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Nervo Isquiático/imunologia , Nervo Isquiático/fisiopatologia , Ciática/imunologia , Ciática/metabolismo , Ciática/fisiopatologia
14.
Eur J Pharmacol ; 484(2-3): 183-91, 2004 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-14744602

RESUMO

Interleukin-6 (IL-6) is markedly upregulated in the peripheral and central nervous systems following nerve injury; however, the functional effects of this are unclear. This study investigates the effect of peripheral interleukin-6 on nociceptive transmission in naive and neuropathic states. Using an in vitro rat skin-nerve preparation, 50 ng interleukin-6 inhibited responses of single nociceptive fibers to noxious heat. A 20-ng sample of interleukin-6 only inhibited heat responses in the presence of soluble interleukin-6 receptors. To examine in vivo effects of peripheral interleukin-6, extracellular recordings from dorsal horn neurons were made in anaesthetised naive, sham-operated and neuropathic (spinal nerve ligated) rats. Peripheral interleukin-6 (40-100 ng) markedly inhibited all naturally evoked neuronal responses in naive rats, yet only neuronal responses to heat in neuropathic rats. Behaviourally, intraplantar administration of interleukin-6 (0.01-1 microg) elicited ipsilateral thermal hypoalgesia in naive rats. Thus, interleukin-6 inhibits normal peripheral nociceptive transmission, yet such anti-nociceptive effects are attenuated following nerve injury in a modality-specific manner.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Interleucina-6/farmacologia , Medição da Dor/efeitos dos fármacos , Nervos Espinhais/efeitos dos fármacos , Nervos Espinhais/fisiopatologia , Potenciais de Ação/fisiologia , Vias Aferentes/efeitos dos fármacos , Vias Aferentes/lesões , Vias Aferentes/fisiologia , Animais , Temperatura Alta/efeitos adversos , Masculino , Medição da Dor/métodos , Traumatismos dos Nervos Periféricos , Nervos Periféricos/efeitos dos fármacos , Nervos Periféricos/fisiologia , Ratos , Ratos Sprague-Dawley , Nervos Espinhais/lesões , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
15.
Pain ; 107(1-2): 33-40, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14715386

RESUMO

Chronic pain resulting from metastatic bone cancer remains poorly understood and resistant to treatment. Here we have examined the effect of the novel COX-2 enzyme inhibitor lumiracoxib in a model of bone cancer pain in the rat. Lumiracoxib was administered orally twice daily from day 10 to day 20 after injection of MRMT-1 tumour cells into one tibia. Mechanical hyperalgesia, measured as the reduction in weight-bearing of the ipsilateral limb, and the development of static and dynamic allodynia were significantly inhibited by repeated lumaricoxib administration. A similar reduction in hyperalgesia and allodynia was noted after twice daily administration of another COX-2 inhibitor, valdecoxib, whilst a single acute administration of either drug on day 20, produced no anti-nociceptive activity. Bone mineral density measurements, radiological scores and histological analysis showed that chronic lumaricoxib treatment also significantly attenuated bone destruction induced by tumour cell injection. These data indicate that lumiracoxib and other COX-2 inhibitors have potential therapeutic benefit in the treatment of bone cancer pain.


Assuntos
Neoplasias Ósseas/complicações , Inibidores de Ciclo-Oxigenase/uso terapêutico , Compostos Orgânicos/uso terapêutico , Dor/tratamento farmacológico , Análise de Variância , Animais , Comportamento Animal , Densidade Óssea , Neoplasias Ósseas/patologia , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Diclofenaco/análogos & derivados , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Adjuvante de Freund , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Inflamação/tratamento farmacológico , Inflamação/etiologia , Isoenzimas/antagonistas & inibidores , Isoxazóis/uso terapêutico , Dor/induzido quimicamente , Dor/etiologia , Medição da Dor , Prostaglandina-Endoperóxido Sintases , Radiologia , Ratos , Ratos Sprague-Dawley , Sulfonamidas/uso terapêutico , Fatores de Tempo , Células Tumorais Cultivadas
16.
Brain Res ; 984(1-2): 54-62, 2003 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-12932839

RESUMO

Interleukin-6 (IL-6) is a neuropoietic cytokine which is dramatically upregulated following peripheral nerve injury at the site of injury, in the dorsal root ganglion (DRG) and in the spinal cord. The functional effects of IL-6 in nociception in normal conditions and following nerve injury are unclear. Thus the aim of this study was to assess the effect of spinal IL-6 administration on nociceptive transmission in naive, sham-operated and neuropathic (spinal nerve ligation, SNL) rats using in vivo electrophysiology to elucidate the possible role of IL-6 in neuropathic pain. In anaesthetised rats, extracellular recordings were made from individual convergent dorsal horn neurones following electrical and natural (mechanical and thermal) stimulation of peripheral receptive fields. Exogenous spinal IL-6 (100-500 ng) had no significant effect on electrically evoked neuronal responses in naive rats. In contrast, following neuropathy, spinal IL-6 produced a dose-related inhibition of the electrically evoked C-fibre, initial C-fibre and measures of neuronal hyperexcitability (post discharge and wind-up). In addition, spinal IL-6 markedly inhibited mechanical neuronal responses in neuropathic rats. Higher doses of spinal IL-6 also inhibited, to a lesser degree, the initial C-fibre, post discharge and wind-up responses in sham-operated rats. These studies show that following nerve injury the actions of the cytokine alter so that spinal administration of IL-6 elicits anti-nociceptive effects not observed under normal conditions. Moreover, the inhibitory effects of IL-6 on C-fibre activity and neuronal hyperexcitability, suggest IL-6 to be a potential modulator of neuropathic pain.


Assuntos
Interleucina-6/fisiologia , Inibição Neural/fisiologia , Medição da Dor , Nervos Espinhais/fisiologia , Transmissão Sináptica/fisiologia , Animais , Relação Dose-Resposta a Droga , Interleucina-6/farmacologia , Masculino , Medição da Dor/métodos , Doenças do Sistema Nervoso Periférico/fisiopatologia , Ratos , Ratos Sprague-Dawley , Medula Espinal/fisiologia
17.
Pain ; 100(3): 219-229, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12467993

RESUMO

Inoculation of syngeneic MRMT-1 mammary tumour cells into one tibia of female rats produced tumour growth within the bone associated with a reduction in bone mineral density (BMD) and bone mineral content (BMC), severe radiological signs of bone destruction, together with the development of behavioural mechanical allodynia and hyperalgesia. Histological and radiological examination showed that chronic treatment with the bisphosphonate, zoledronic acid (30 microg/kg, s.c.), for 19 days significantly inhibited tumour proliferation and preserved the cortical and trabecular bone structure. In addition, BMD and BMC were preserved and a dramatic reduction of tartrate resistant acid phosphatase-positive polykaryocytes (osteoclasts) was observed. In behavioural tests, chronic treatment with zoledronic acid but not the significantly less effective bisphosphonate, pamidronate, or the selective COX-2 inhibitor, celebrex, attenuated mechanical allodynia and hyperalgesia in the affected hind paw. Zoledronic acid also attenuated mechanical hyperalgesia associated with chronic peripheral neuropathy and inflammation in the rat. In contrast, pamidronate or clodronate did not have any anti-hyperalgesic effect on mechanical hyperalgesia in the neuropathic and inflammatory pain models. We conclude that zoledronic acid, in addition to, or independent from, its anti-metastatic and bone preserving therapeutic effects, is an anti-nociceptive agent in a rat model of metastatic cancer pain. This unique property of zoledronic acid amongst the bisphosphonate class of compounds could make this drug a preferred choice for the treatment of painful bone metastases in the clinic.


Assuntos
Neoplasias Ósseas/complicações , Neoplasias Ósseas/tratamento farmacológico , Difosfonatos/administração & dosagem , Imidazóis/administração & dosagem , Dor/tratamento farmacológico , Dor/etiologia , Animais , Densidade Óssea/efeitos dos fármacos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Ácido Clodrônico/administração & dosagem , Feminino , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Hiperestesia/tratamento farmacológico , Hiperestesia/etiologia , Modelos Animais , Transplante de Neoplasias , Variações Dependentes do Observador , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Pamidronato , Radiografia , Ratos , Ratos Sprague-Dawley , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tíbia/efeitos dos fármacos , Tíbia/patologia , Tíbia/cirurgia , Tato/efeitos dos fármacos , Resultado do Tratamento , Ácido Zoledrônico
18.
J Neurosci ; 22(18): 8139-47, 2002 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12223568

RESUMO

The excitation of nociceptive sensory neurons by ATP released in injured tissue is believed to be mediated partly by P2X3 receptors. Although an analysis of P2X3 knock-out mice has revealed some deficits in nociceptive signaling, detailed analysis of the role of these receptors is hampered by the lack of potent specific pharmacological tools. Here we have used antisense oligonucleotides (ASOs) to downregulate P2X3 receptors to examine their role in models of chronic pain in the rat. ASOs and control missense oligonucleotides (180 microg/d) were administered intrathecally to naive rats for up to 7 d via a lumbar indwelling cannula attached to an osmotic minipump. Functional downregulation of the receptors was confirmed by alphabeta-methylene ATP injection into the hindpaw, which evoked significantly less mechanical hyperalgesia as early as 2 d after treatment with ASOs relative to controls. At this time point, P2X3 protein levels were significantly downregulated in lumbar L4 and L5 dorsal root ganglia. After 7 d of ASO treatment, P2X3 protein levels were reduced in the primary afferent terminals in the lumbar dorsal horn of the spinal cord. In models of neuropathic (partial sciatic ligation) and inflammatory (complete Freund's adjuvant) pain, inhibition of the development of mechanical hyperalgesia as well as significant reversal of established hyperalgesia were observed within 2 d of ASO treatment. The time course of the reversal of hyperalgesia is consistent with downregulation of P2X3 receptor protein and function. This study demonstrates the utility of ASO approaches for validating gene targets in in vivo pain models and provides evidence for a role of P2X3 receptors in the pathophysiology of chronic pain.


Assuntos
Hiperalgesia/fisiopatologia , Inflamação/fisiopatologia , Neurônios Aferentes/metabolismo , Receptores Purinérgicos P2/metabolismo , Neuropatia Ciática/fisiopatologia , Trifosfato de Adenosina/análogos & derivados , Animais , Modelos Animais de Doenças , Regulação para Baixo/fisiologia , Adjuvante de Freund , Membro Posterior , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Inflamação/induzido quimicamente , Injeções Espinhais , Ligadura , Masculino , Neurônios Aferentes/citologia , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/farmacologia , Medição da Dor , Subunidades Proteicas , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2X3 , Neuropatia Ciática/tratamento farmacológico
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