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2.
Support Care Cancer ; 30(8): 6947-6953, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35543818

RESUMO

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of chemotherapy, especially after taxane-based therapy. This study aimed to examine the relationship between symptoms of anxiety and depression before the start of taxane-based chemotherapy and the development of CIPN in women with breast cancer. METHODS: In this prospective study, women with breast cancer receiving taxane-based (neo)adjuvant chemotherapy were recruited from four hospitals in the Netherlands. Patients completed questionnaires assessing anxiety and depressive symptoms before treatment and CIPN before treatment (T0), 6 weeks after start of treatment (T1), after the last cycle of chemotherapy (T2), and 6 months after the end of treatment (T3). Mixed model analyses were used to investigate whether medium/high levels of anxiety or depression at baseline are associated with the level of CIPN during and after treatment. RESULTS: Among the 61 participating women, 14 (23%) reported medium/high levels of anxiety and 29 (47.5%) reported medium/high levels of depressive symptoms at baseline. The group of women with medium/high baseline levels of anxiety showed a significantly higher increase in CIPN during and after chemotherapy than women with low baseline levels of anxiety (p < .001). No relationship between depressive symptoms at baseline and the development of CIPN was found. CONCLUSION: This study showed that baseline medium to high levels of anxiety but not depressive symptoms impacted the development of CIPN during and in the 6 months after treatment.


Assuntos
Antineoplásicos , Neoplasias da Mama , Doenças do Sistema Nervoso Periférico , Antineoplásicos/efeitos adversos , Ansiedade/induzido quimicamente , Ansiedade/epidemiologia , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/epidemiologia , Estudos Prospectivos , Taxoides
3.
J Palliat Med ; 24(12): 1789-1797, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34415798

RESUMO

Background: Intensive end-of-life care (i.e., the overuse of treatments and hospital resources in the last months of life), is undesirable since it has a minimal clinical benefit with a substantial financial burden. The aim was to investigate the care in the last three months of life (end-of-life [EOL]) in castration-resistant prostate cancer (CRPC). Methods: Castration-resistant prostate cancer registry (CAPRI) is an investigator-initiated, observational multicenter cohort study in 20 hospitals retrospectively including patients diagnosed with CRPC between 2010 and 2016. High-intensity care was defined as the initiation of life-prolonging drugs (LPDs) in the last month, continuation of LPD in last 14 days, >1 admission, admission duration ≥14 days, and/or intensive care admission in last three months of life. Descriptive and binary logistic regression analyses were performed. Results: High-intensity care was experienced by 41% of 2429 patients in the EOL period. Multivariable analysis showed that age (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.97-0.99), performance status (OR 0.57, 95% CI 0.33-0.97), time from CRPC to EOL (OR 0.98, 95% CI 0.97-0.98), referral to a medical oncologist (OR 1.99, 95% CI 1.55-2.55), prior LPD treatment (>1 line OR 1.72, 95% CI 1.31-2.28), and opioid use (OR 1.45, 95% CI 1.08-1.95) were significantly associated with high-intensity care. Conclusions: High-intensity care in EOL is not easily justifiable due to high economic cost and little effect on life span, but further research is awaited to give insight in the effect on patients' and their caregivers' quality of life.


Assuntos
Uso Excessivo dos Serviços de Saúde , Neoplasias de Próstata Resistentes à Castração , Assistência Terminal , Humanos , Masculino , Países Baixos , Neoplasias de Próstata Resistentes à Castração/terapia , Sistema de Registros , Estudos Retrospectivos , Assistência Terminal/métodos
4.
Oncologist ; 26(10): 854-864, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34251745

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) recurrence rates following locoregional treatment are high. As multireceptor tyrosine kinase inhibitors targeting vascular endothelial growth factor receptors (VEGFRs) are effective in advanced HCC, we assessed the efficacy and safety of neoadjuvant systemic treatment with dovitinib in early- and intermediate-stage HCC. MATERIALS AND METHODS: Twenty-four patients with modified Child-Pugh class A early- and intermediate-stage HCC received neoadjuvant oral dovitinib 500 mg daily (5 days on/2 days off) for 4 weeks, followed by locoregional therapy. Primary endpoints were objective response rates and intratumoral blood flow changes. Secondary endpoints were safety, pharmacodynamical plasma markers of VEGFR-blockade, time to progression (TTP), and overall survival (OS). RESULTS: Modified RECIST overall response rate was 48%, including 13% complete remission, and despite dose reduction/interruption in 83% of patients, intratumoral perfusion index decreased significantly. Grade 3-4 adverse events, most frequently (on-target) hypertension (54%), fatigue (25%), and thrombocytopenia (21%), occurred in 88% of patients. Plasma VEGF-A, VEGF-D, and placental growth factor increased significantly, whereas sTie-2 decreased, consistent with VEGFR-blockade. Following neoadjuvant dovitinib, all patients could proceed to their original planned locoregional treatment. No delayed toxicity occurred. Seven patients (three early, four intermediate stage) underwent orthotopic liver transplant after median 11.4 months. Censoring at transplantation, median TTP and OS were 16.8 and 34.8 months respectively; median cancer-specific survival was not reached. CONCLUSION: Already after a short 4-week dovitinib treatment period, intratumoral blood flow reduction and modest antitumor responses were observed. Although these results support use of systemic neoadjuvant strategies, the poor tolerability indicates that dovitinib dose adaptations are required in HCC. IMPLICATIONS FOR PRACTICE: Orthotopic liver transplantation may cure early and intermediate-stage hepatocellular carcinoma. Considering the expected waiting time >6 months because of donor liver scarcity, there is an unmet need for effective neoadjuvant downsizing strategies. Angiogenesis inhibition by dovitinib does not negatively affect subsequent invasive procedures, is safe to administer immediately before locoregional therapy, and may provide a novel treatment approach to improve patient outcomes if tolerability in patients with hepatocellular carcinoma can be improved by therapeutic drug monitoring and personalized dosing.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Inibidores da Angiogênese/uso terapêutico , Benzimidazóis , Carcinoma Hepatocelular/tratamento farmacológico , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Doadores Vivos , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Fator de Crescimento Placentário , Quinolonas , Fator A de Crescimento do Endotélio Vascular
5.
Eur Urol Oncol ; 4(4): 618-627, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-31601523

RESUMO

BACKGROUND: Cross resistance between androgen-receptor targeting therapies (ARTs) (abiraterone acetate plus prednisone [ABI+P] or enzalutamide [ENZ]) for treatment of metastatic castration-resistant prostate cancer (mCRPC) may affect responses to second ART (ART2). OBJECTIVE: To establish treatment duration and prostate-specific antigen (PSA) response of ART2 in real-world mCRPC patients treated with or without other life-prolonging drugs (LPDs; ie, docetaxel, cabazitaxel, or radium-223) between ART1 and ART2. DESIGN, SETTING, AND PARTICIPANTS: Castration-resistant prostate cancer patients, diagnosed between 2010 and 2016 were retrospectively registered in Castration-resistant Prostate Cancer Registry (CAPRI). Patients treated with both ARTs were clustered into two subgroups: ART1>ART2 or ART1>LPD>ART2. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Outcomes were ≥50% PSA response and treatment duration of ART2. Descriptive statistics and binary logistic regression after multiple imputations were performed. RESULTS AND LIMITATIONS: A total of 273 patients were included with a median follow-up of 8.4 mo from ART2. Patients with ART1>ART2 were older and had favourable prognostic characteristics at ART2 baseline compared with patients with ART1>LPD>ART2. No differences between ART1>ART2 and ART1>LPD>ART2 were found in PSA response and treatment duration. Multivariate analysis suggested that PSA response of ART2 was less likely in patients with visceral metastases (odds ratio [OR] 0.143, p=0.04) and more likely in patients with a relatively longer duration of androgen-deprivation treatment (OR 1.028, p=0.01) and with ABI + P before ENZ (OR 3.192, p=0.02). A major limitation of this study was missing data, a common problem in retrospective observational research. CONCLUSIONS: The effect of ART2 seems to be low, with a low PSA response rate and a short treatment duration irrespective of interposed chemotherapy or radium-223, especially in patients with short time on castration, visceral disease, and ENZ before ABI+P. PATIENT SUMMARY: We observed no differences in outcomes of patients treated with sequential abiraterone acetate plus prednisone (ABI+P) and enzalutamide (ENZ) with or without interposed chemotherapy or radium-223. In general, outcomes were lower than those in randomised trials, questioning the additional effect of second treatment with ABI+P or ENZ in daily practice.


Assuntos
Preparações Farmacêuticas , Neoplasias de Próstata Resistentes à Castração , Antagonistas de Androgênios , Androgênios , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Sistema de Registros , Estudos Retrospectivos
6.
Biomech Model Mechanobiol ; 16(4): 1095-1102, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28220319

RESUMO

Donor livers available to transplant for patients with end-stage liver disease are in severe shortage. One possible avenue to expand the donor pool is to recondition livers that would be otherwise discarded due to excessive fat content. Severely steatotic livers (also known as fatty livers) are highly susceptible to ischemia-reperfusion injury and as a result, primary liver non-function post-transplantation. Prior studies in isolated perfused rat livers suggest that "defatting" may be possible in a timeframe of a few hours; thus, it is conceivable that fatty liver grafts could be recovered by machine perfusion to clear stored fat from the organ prior to transplantation. However, studies using hepatoma cells and adult hepatocytes made fatty in culture report that defatting may take several days. Because cell culture studies were done in static conditions, we hypothesized that the defatting kinetics are highly sensitive to flow-mediated transport of metabolites. To investigate this question, we experimentally evaluated the effect of increasing flow rate on the defatting kinetics of cultured HepG2 cells and developed an in silico combined reaction-transport model to identify possible rate-limiting steps in the defatting process. We found that in cultured fatty HepG2 cells, the time required to clear stored fat down to lean control cells can be reduced from 48 to 4-6 h by switching from static to flow conditions. The flow required resulted in a fluid shear of .008 Pa, which did not adversely affect hepatic function. The reaction-transport model suggests that the transport of L-carnitine, which is the carrier responsible for taking free fatty acids into the mitochondria, is the key rate-limiting process in defatting that was modulated by flow. Therefore, we can ensure higher levels of L-carnitine uptake by the cells by choosing flow rates that minimize the limiting mass transport while minimizing shear stress.


Assuntos
Fígado Gorduroso/metabolismo , Hepatócitos/metabolismo , Transplante de Fígado/métodos , Fígado/metabolismo , Triglicerídeos/metabolismo , Animais , Células Hep G2 , Humanos , Fígado/fisiopatologia , Ratos , Fatores de Tempo
7.
Med Decis Making ; 37(3): 179-192, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27681991

RESUMO

BACKGROUND: Treatment decision making is often guided by evidence-based probabilities, which may be presented to patients during consultations. These probabilities are intrinsically imperfect and embody 2 types of uncertainties: aleatory uncertainty arising from the unpredictability of future events and epistemic uncertainty arising from limitations in the reliability and accuracy of probability estimates. Risk communication experts have recommended disclosing uncertainty. We examined whether uncertainty was discussed during cancer consultations and whether and how patients perceived uncertainty. METHODS: Consecutive patient consultations with medical oncologists discussing adjuvant treatment in early-stage breast cancer were audiotaped, transcribed, and coded. Patients were interviewed after the consultation to gain insight into their perceptions of uncertainty. RESULTS: In total, 198 patients were included by 27 oncologists. Uncertainty was disclosed in 49% (97/197) of consultations. In those 97 consultations, 23 allusions to epistemic uncertainty were made and 84 allusions to aleatory uncertainty. Overall, the allusions to the precision of the probabilities were somewhat ambiguous. Interviewed patients mainly referred to aleatory uncertainty if not prompted about epistemic uncertainty. Even when specifically asked about epistemic uncertainty, 1 in 4 utterances referred to aleatory uncertainty. When talking about epistemic uncertainty, many patients contradicted themselves. In addition, 1 in 10 patients seemed not to realize that the probabilities communicated during the consultation are imperfect. CONCLUSIONS: Uncertainty is conveyed in only half of patient consultations. When uncertainty is communicated, oncologists mainly refer to aleatory uncertainty. This is also the type of uncertainty that most patients perceive and seem comfortable discussing. Given that it is increasingly common for clinicians to discuss outcome probabilities with their patients, guidance on whether and how to best communicate uncertainty is urgently needed.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/psicologia , Comunicação , Oncologia , Incerteza , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Tomada de Decisões , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Percepção , Probabilidade , Prognóstico , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Saúde da Mulher
8.
Metabolites ; 6(1)2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26742084

RESUMO

Methods that rapidly decrease fat in steatotic hepatocytes may be helpful to recover severely fatty livers for transplantation. Defatting kinetics are highly dependent upon the extracellular medium composition; however, the pathways involved are poorly understood. Steatosis was induced in human hepatoma cells (HepG2) by exposure to high levels of free fatty acids, followed by defatting using plain medium containing no fatty acids, or medium supplemented with a cocktail of defatting agents previously described before. We measured the levels of 28 extracellular metabolites and intracellular triglyceride, and fed the data into a steady-state mass balance model to estimate strictly intracellular fluxes. We found that during defatting, triglyceride content decreased, while beta-oxidation, the tricarboxylic acid cycle, and the urea cycle increased. These fluxes were augmented by defatting agents, and even more so by hyperoxic conditions. In all defatting conditions, the rate of extracellular glucose uptake/release was very small compared to the internal supply from glycogenolysis, and glycolysis remained highly active. Thus, in steatotic HepG2 cells, glycolysis and fatty acid oxidation may co-exist. Together, these pathways generate reducing equivalents that are supplied to mitochondrial oxidative phosphorylation.

9.
Biochem Biophys Res Commun ; 458(1): 8-13, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25625213

RESUMO

During wound healing, fibroblasts deposit extracellular matrix that guides angiogenesis and supports the migration and proliferation of cells that eventually form the scar. They also promote wound closure via differentiation into α-smooth muscle actin (SMA)-expressing myofibroblasts, which cause wound contraction. Low oxygen tension typical of chronic nonhealing wounds inhibits fibroblast collagen production and differentiation. It has been suggested that hypoxic mesenchymal stromal cells (MSCs) secrete factors that promote wound healing in animal models; however, it is unclear whether these factors are equally effective on the target cells in a hypoxic wound environment. Here we investigated the impact of MSC-derived soluble factors on the function of fibroblasts cultured in hypoxic fibroblast-populated collagen lattices (FPCLs). Hypoxia alone significantly decreased FPCL contraction and α-SMA expression. MSC-conditioned medium restored hypoxic FPCL contraction and α-SMA expression to levels similar to normoxic FPCLs. SB431542, an inhibitor of transforming growth factor-ß1 (TGF-ß1)-mediated signaling, blocked most of the MSC effect on FPCL contraction, while exogenous TGF-ß1 at levels similar to that secreted by MSCs reproduced the MSC effect. These results suggest that TGF-ß1 is a major paracrine signal secreted by MSCs that can restore fibroblast functions relevant to the wound healing process and that are impaired in hypoxia.


Assuntos
Actinas/metabolismo , Fibroblastos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Alginatos , Diferenciação Celular , Hipóxia Celular/fisiologia , Células Cultivadas , Células Imobilizadas , Colágeno/metabolismo , Meios de Cultivo Condicionados/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Ácido Glucurônico , Ácidos Hexurônicos , Humanos , Células-Tronco Mesenquimais/citologia , Músculo Liso/metabolismo , Miofibroblastos/metabolismo , Pele/citologia , Pele/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Cicatrização
10.
Biotechnol Bioeng ; 111(11): 2239-51, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24891120

RESUMO

Understanding the regulatory networks which control specific macrophage phenotypes is essential in identifying novel targets to correct macrophage mediated clinical disorders, often accompanied by inflammatory events. Since mesenchymal stromal cells (MSCs) have been shown to play key roles in regulating immune functions predominantly via a large number of secreted products, we used a fractional factorial approach to streamline experimental evaluation of MSC mediated inflammatory macrophage regulation. Our macrophage reprogramming metrics, human bone marrow MSC attenuation of macrophage pro-inflammatory M1 TNFα secretion and simultaneous enhanced expression of the M2 macrophage marker, CD206, were used as analysis endpoints. Objective evaluation of a panel of MSC secreted mediators indicated that PGE2 alone was sufficient in facilitating macrophage reprogramming, while IL4 only provided partial reprogramming. Inhibiting stromal cell PGE2 secretion with Indomethacin, reversed the macrophage reprogramming effect. PGE2 reprogramming was mediated through the EP4 receptor and indirectly through the CREB signaling pathway as GSK3 specific inhibitors induced M1 macrophages to express CD206. This reprogramming pathway functioned independently from the M1 suppression pathway, as neither CREB nor GSK3 inhibition reversed PGE2 TNF-α secretion attenuation. In conclusion, fractional factorial experimental design identified stromal derived PGE2 as the factor most important in facilitating macrophage reprogramming, albeit via two unique pathways.


Assuntos
Dinoprostona/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Humanos , Interleucina-4/metabolismo , Lectinas Tipo C/análise , Macrófagos/química , Receptor de Manose , Lectinas de Ligação a Manose/análise , Fenótipo , Receptores de Superfície Celular/análise , Fator de Necrose Tumoral alfa/metabolismo
11.
Liver Transpl ; 20(8): 1000-11, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24802973

RESUMO

Macrosteatotic livers exhibit elevated intrahepatic triglyceride (TG) levels in the form of large lipid droplets (LDs), reduced adenosine triphosphate (ATP) levels, and elevated reactive oxygen species (ROS) levels, and this contributes to their elevated sensitivity to ischemia/reperfusion injury during transplantation. Reducing macrosteatosis in living donors through dieting has been shown to improve transplant outcomes. Accomplishing the same feat for deceased donor grafts would require ex vivo exposure to potent defatting agents. Here we used a rat hepatocyte culture system exhibiting a macrosteatotic LD morphology, elevated TG levels, and an elevated sensitivity to hypoxia/reoxygenation (H/R) to test for such agents and ameliorate H/R sensitivity. Macrosteatotic hepatocyte preconditioning for 48 hours with a defatting cocktail that was previously developed to promote TG catabolism reduced the number of macrosteatotic LDs and intracellular TG levels by 82% and 27%, respectively, but it did not ameliorate sensitivity to H/R. Supplementation of this cocktail with l-carnitine, together with hyperoxic exposure, yielded a similar reduction in the number of macrosteatotic LDs and a 57% reduction in intrahepatic TG storage, likely by increasing the supply of acetyl coenzyme A to mitochondria, as indicated by a 70% increase in ketone body secretion. Furthermore, this treatment reduced ROS levels by 32%, increased ATP levels by 27% (to levels near those of lean controls), and completely abolished H/R sensitivity as indicated by approximately 85% viability after H/R and the reduction of cytosolic lactate dehydrogenase release to levels seen in lean controls. Cultures maintained for 48 hours after H/R were approximately 83% viable and exhibited superior urea secretion and bile canalicular transport in comparison with untreated macrosteatotic cultures. In conclusion, these findings show that the elevated sensitivity of macrosteatotic hepatocytes to H/R can be overcome by defatting agents, and they suggest a possible route for the recovery of discarded macrosteatotic grafts.


Assuntos
Fígado Gorduroso/patologia , Hepatócitos/citologia , Transplante de Fígado/métodos , Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Acetilcoenzima A/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Carnitina/sangue , Citosol/enzimologia , Fígado Gorduroso/terapia , Hepatócitos/efeitos dos fármacos , Hipóxia , Corpos Cetônicos/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Mitocôndrias/metabolismo , Perfusão , Ratos , Ratos Zucker , Espécies Reativas de Oxigênio , Condicionamento Pré-Transplante , Triglicerídeos/metabolismo
12.
Lancet Oncol ; 15(7): 722-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24836274

RESUMO

BACKGROUND: Adjuvant! Online is a prediction tool that can be used to aid clinical decision making in patients with breast cancer. It was developed in a patient population aged 69 years or younger, and subsequent validation studies included small numbers of older patients. Since older patients with breast cancer differ from younger patients in many aspects, the aim of this study was to investigate the validity of Adjuvant! Online in a large cohort of unselected older patients. METHODS: We included patients from the population-based FOCUS cohort, which included all consecutive patients aged 65 years or older who were diagnosed with invasive or in-situ breast cancer between Jan 1, 1997, and Dec 31, 2004, in the southwestern part of the Netherlands. We included all patients who fulfilled the criteria as stated by Adjuvant! Online: patients with unilateral, unicentric, invasive adenocarcinoma; no evidence of metastatic or residual disease; no evidence of T4 features; and no evidence of inflammatory breast cancer. We entered data from all patients with the "average for age" comorbidity status (model 1) and with an individualised comorbidity status (model 2). FINDINGS: We included 2012 patients. Median age of patients in the cohort was 74·0 years (IQR 69·0-79·0). 904 (45%) of 2012 patients died during follow-up, whereas 326 (16%) patients had recurrence. Median follow-up for overall survival was 9·0 years (IQR 7·4-10·7), and 6·6 years (4·4-6·6) for patients without recurrence. Using model 1, Adjuvant! Online overestimated 10-year overall survival by 9·8% ([95% CI 5·9-13·7], p<0·0001) and 10-year cumulative recurrence survival by 8·7% ([6·7-10·7], p<0·0001). By contrast, when using model 2, Adjuvant! Online underestimated the 10-year overall survival by -17·1% ([95% CI -21·0 to -13·2], p<0·0001). However, when using model 2, Adjuvant! Online predicted cumulative recurrence accurately in all patients (-0·7% [95% CI -2·7-1·3], p=0·48). INTERPRETATION: Adjuvant! Online does not accurately predict overall survival and recurrence in older patients with early breast cancer. FUNDING: Dutch Cancer Foundation.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Internet , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Quimioterapia Adjuvante , Estudos de Coortes , Feminino , Humanos , Curva ROC
13.
Liver Transpl ; 20(2): 228-36, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24339411

RESUMO

Large-droplet macrovesicular steatosis (ld-MaS) in more than 30% of liver graft hepatocytes is a major risk factor for liver transplantation. An accurate assessment of the ld-MaS percentage is crucial for determining liver graft transplantability, which is currently based on pathologists' evaluations of hematoxylin and eosin (H&E)-stained liver histology specimens, with the predominant criteria being the relative size of the lipid droplets (LDs) and their propensity to displace a hepatocyte's nucleus to the cell periphery. Automated image analysis systems aimed at objectively and reproducibly quantifying ld-MaS do not accurately differentiate large LDs from small-droplet macrovesicular steatosis and do not take into account LD-mediated nuclear displacement; this leads to a poor correlation with pathologists' assessments. Here we present an improved image analysis method that incorporates nuclear displacement as a key image feature for segmenting and classifying ld-MaS from H&E-stained liver histology slides. 52,000 LDs in 54 digital images from 9 patients were analyzed, and the performance of the proposed method was compared against the performance of current image analysis methods and the ld-MaS percentage evaluations of 2 trained pathologists from different centers. We show that combining nuclear displacement and LD size information significantly improves the separation between large and small macrovesicular LDs (specificity = 93.7%, sensitivity = 99.3%) and the correlation with pathologists' ld-MaS percentage assessments (linear regression coefficient of determination = 0.97). This performance vastly exceeds that of other automated image analyzers, which typically underestimate or overestimate pathologists' ld-MaS scores. This work demonstrates the potential of automated ld-MaS analysis in monitoring the steatotic state of livers. The image analysis principles demonstrated here may help to standardize ld-MaS scores among centers and ultimately help in the process of determining liver graft transplantability.


Assuntos
Amarelo de Eosina-(YS)/química , Fígado Gorduroso/patologia , Hematoxilina/química , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Núcleo Celular/metabolismo , Análise por Conglomerados , Árvores de Decisões , Sobrevivência de Enxerto , Hepatócitos/citologia , Hepatócitos/patologia , Humanos , Modelos Lineares , Fígado/patologia , Transplante de Fígado , Reconhecimento Automatizado de Padrão , Fatores de Risco , Sensibilidade e Especificidade
14.
J Hepatol ; 59(6): 1307-14, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23872604

RESUMO

BACKGROUND & AIMS: A common cause of liver donor ineligibility is macrosteatosis. Recovery of such livers could enhance donor availability. Living donor studies have shown diet-induced reduction of macrosteatosis enables transplantation. However, cadaveric liver macrosteatotic reduction must be performed ex vivo within hours. Towards this goal, we investigated the effect of accelerated macrosteatosis reduction on hepatocyte viability and function using a novel system of macrosteatotic hepatocytes. METHODS: Hepatocytes isolated from lean Zucker rats were cultured in a collagen sandwich, incubated for 6 days in fatty acid-supplemented medium to induce steatosis, and then switched for 2 days to medium supplemented with lipid metabolism promoting agents. Intracellular lipid droplet size distribution and triglyceride, viability, albumin and urea secretion, and bile canalicular function were measured. RESULTS: Fatty acid-supplemented medium induced microsteatosis in 3 days and macrosteatosis in 6 days, the latter evidenced by large lipid droplets dislocating the nucleus to the cell periphery. Macrosteatosis significantly impaired all functions tested. Macrosteatosis decreased upon returning hepatocytes to standard medium, and the rate of decrease was 4-fold faster with supplemented agents, yielding 80% reduction in 2 days. Viability of macrosteatosis reduced hepatocytes was similar to control lean cells. Accelerated macrosteatotic reduction led to faster recovery of urea secretion and bile canalicular function, but not of albumin secretion. CONCLUSIONS: Macrosteatosis reversibly decreases hepatocyte function and supplementary agents accelerate macrosteatosis reduction and some functional restoration with no effect on viability. This in vitro model may be useful to screen agents for macrosteatotic reduction in livers before transplantation.


Assuntos
Fígado Gorduroso/etiologia , Hepatócitos/fisiologia , Animais , Sobrevivência Celular , Células Cultivadas , Humanos , Masculino , Ratos , Ratos Zucker
15.
Br J Ophthalmol ; 93(8): 1042-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19429579

RESUMO

AIMS: To evaluate the posthepatectomy survival of uveal melanoma patients with liver metastases. METHODS: Data were collected from the files in the Departments of Ophthalmology, General Surgery and Oncology, for uveal melanoma patients who were seen in the Ocular Oncology Clinic at the Hadassah Medical Center from 1988 to 2007. The main outcome was posthepatectomy survival. Statistical analysis was performed using JMP statistical software. RESULTS: Of the 558 patients, 74 (13%) developed metastases after a median of 35.0 months from the initial diagnosis. Thirty-five patients underwent hepatectomy. These patients had similar clinical characteristics as those who did not undergo hepatectomy. The median survival time from the detection of metastasis was 3.7-fold higher in the operated patients in comparison with the non-operated patients. Posthepatectomy survival of patients who were found in surgery to have 1-5 metastatic nodules was 3.1 times longer than those with six or more lesions. The hepatectomies of 13 patients resulted in complete resection of the hepatic metastases with clean histological margins (R0). These patients survived 1.9 times longer than those with residual disease (R1/R2). CONCLUSION: It is possible to extend significantly the life expectancy of uveal melanoma patients who develop isolated hepatic metastases by complete resection of the lesions.


Assuntos
Neoplasias Hepáticas/secundário , Melanoma/secundário , Neoplasias Uveais , Seguimentos , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Melanoma/mortalidade , Melanoma/cirurgia , Análise de Sobrevida , Resultado do Tratamento
16.
Oncologist ; 13(11): 1149-54, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18984875

RESUMO

A 39-year-old male patient with a favorable prognosis stage IIB metastatic malignant germ cell tumor (GCT) and elevated pre- and postorchiectomy serum human chorionic gonadotropin (hCG) was treated with three courses of combination chemotherapy resulting in a rapid normalization of his serum hCG. Within 2 months after the cessation of chemotherapy, his serum hCG increased again, suggesting tumor recurrence. Pathological examination of the resected residual retroperitoneal lymph nodes revealed no vital tumor cells. Based on the further rise in his serum hCG and enlargement of mediastinal lymph nodes on computed tomography scan, the patient underwent second- and third-line chemotherapy, which did not result in normalization of his serum hCG. Reanalysis of stored serum samples with other immunoassays revealed that the elevated serum hCG levels collected before first-line chemotherapy were indeed elevated, but those collected after first-line chemotherapy were all falsely positive. Currently, the patient is still alive and disease free. This is the first report of a male cancer patient who received unneeded second- and third-line chemotherapy for relapse based on false-positive hCG results. We discuss the pitfalls of false-positive serum hCG measurements, including heterophilic antibodies, as in our IgA-deficient patient, and review the literature.


Assuntos
Gonadotropina Coriônica/sangue , Neoplasias Embrionárias de Células Germinativas/sangue , Neoplasias Testiculares/sangue , Adulto , Gonadotropina Coriônica/urina , Reações Falso-Positivas , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Tomografia Computadorizada por Raios X
17.
Theriogenology ; 61(6): 1147-62, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15037002

RESUMO

The Mediterranean tortoise (Testudo graeca) is listed as "Vulnerable" on the IUCN Red List. Reproductive characteristics and means to increase offspring production were studied in T. graeca terrestris in a semi-natural environment. Courtship and mating occurred during early spring for about 4 weeks, followed by a laying season of approximately 2 months, with a second, shorter mating period in the fall. During the first mating, calcified eggs were already present in the uterus; we inferred that sperm from both mating seasons were stored in the oviduct for fertilization of eggs of the second laying cycle and of the following year. Average egg production was 3.8+/-0.3 eggs/year. Most females laid all of their eggs in a single clutch, but 18% laid in a second clutch, 11-21 days later. X-ray radiography revealed calcified eggs in the uterus about 4 weeks before oviposition. All eggs in the uterus were calcified simultaneously and were laid in a single clutch; if a second clutch developed, those eggs were also calcified simultaneously. Based on endoscopic examinations, ovaries were active throughout the entire year. Plasma progesterone concentrations in females were very low and were detected only soon after oviposition ( 440 +/-141 pg/ml). Plasma estradiol concentrations in females varied from 4.1 +/-1.5 pg/ml to 70.2 +/-29.4 pg/ml, with no clear seasonal pattern. Maintaining tortoises at a low environmental temperature (9 +/-1 degrees C versus 28 +/- 1 degrees C) reduced plasma estradiol concentrations. Giving 2mg/kg tamoxifen (TAM) increased plasma estradiol to 220 +/-33 pg/ml when treatment was given in September but not in late October, winter or spring. Treatment with TAM increased the number of eggs laid during the following laying season to 7.3 +/- 1.0 eggs/year, laid in one to three clutches. In males, plasma testosterone concentrations had a seasonal pattern with the onset of a rise in July from 2 to >4ng/ml, a continued increase to a peak of 12.8+/-5.3 ng/ml during November and a decline thereafter. Artificial incubation in sand at 29 +/-1 degrees C shortened the natural incubation time of 103+/-3.1 days to 83.5 +/- 1.3 days, increased hatching rate from 28 to 53%, and increased survival rate from 51 to 71% at 40 weeks of age. In summary, this study provides options for increasing reproductive performance, hatchability and offspring survival in captive Mediterranean tortoises, and may offer new tools for conservation of animals that are on the verge of extinction.


Assuntos
Reprodução , Tartarugas/fisiologia , Animais , Conservação dos Recursos Naturais , Estradiol/sangue , Antagonistas de Estrogênios/farmacologia , Feminino , Masculino , Ovário/fisiologia , Oviposição , Progesterona/sangue , Estações do Ano , Comportamento Sexual Animal , Tamoxifeno/farmacologia , Temperatura , Testosterona/sangue
18.
Exp Eye Res ; 73(2): 265-72, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11446777

RESUMO

cAMP levels in dark and light were studied in dystrophic retinal degeneration slow(rds) mice, which carry a mutation in the rds/peripherin gene. cAMP levels were measured in vivo, in freshly isolated retinas, and in vitro in the presence of glutamate, which confines light modulation to photoreceptors. Experiments were conducted on young animals, when significant numbers of viable photoreceptor cells are present. In vivo levels of cAMP are higher in illuminated rds/rds retinas than levels measured in normal BALB/c retinas. Light-evoked down-regulation of cAMP levels was observed in vitro in normal photoreceptors. These measurements were made in the presence of the cyclic nucleotide phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine; therefore, they reflect an inhibition of cAMP formation. In contrast, light had no effect on cAMP formation in photoreceptors of mutant mice, measured under identical conditions. Thus, elevated levels of cAMP in rds/rds retinas in vivo result from abnormalities in cAMP synthesis in the mutant photoreceptor cells. In addition to regulation by light, cAMP formation in photoreceptor cells is regulated by dopamine, acting through dopamine D4 receptors. A dopamine D2/D4 receptor agonist, quinpirole, reduced cAMP levels in dark-adapted normal retinas in vitro, but not in rds/rds retinas. Our data indicate that alterations in a signal transduction pathway that leads to inhibition of adenylyl cyclase might underlie the abnormalities in cAMP levels in mutant rds/rds retinas. Heterozygous rds/+ photoreceptors demonstrated a normal pattern of light-evoked and quinpirole-mediated down-regulation of cAMP. Thus, partial expression of the normal phenotype is sufficient to render normal characteristics of cAMP regulation to the photoreceptors of the heterozygous mouse. The data obtained in the present study might be relevant to the understanding of photoreceptor pathology of patients with peripherin/rds mutations.


Assuntos
AMP Cíclico/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Receptores Dopaminérgicos/metabolismo , Degeneração Retiniana/metabolismo , Adenilil Ciclases/fisiologia , Análise de Variância , Animais , Adaptação à Escuridão , Agonistas de Dopamina/farmacologia , Regulação para Baixo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Microscopia Eletrônica , Fenótipo , Inibidores de Fosfodiesterase/farmacologia , Quimpirol/farmacologia , Transdução de Sinais/fisiologia , Xantinas/farmacologia
19.
Invest Ophthalmol Vis Sci ; 42(3): 842-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11222548

RESUMO

PURPOSE: To determine the effect of light stress on retinal function and long-term photoreceptor viability in Royal College of Surgeons (RCS) rats and the applicability of the light treatment to the opsin P23H mutant rats. METHODS: RCS rats at postnatal day (P)23 were illuminated with 120 foot-candles (fc) white light for 10 hours. Photoreceptor survival and basic fibroblast growth factor (bFGF) expression were measured at P60 and P83. Retinal function was evaluated by electroretinography. Opsin P23H transgenic rats were treated with light at P28 and analyzed at P70 for photoreceptor viability, ultrastructure, and bFGF expression. RESULTS: Light-treated RCS rats at P60 had four to five rows of nuclei versus one to two rows in untreated littermates. The average amplitude of the ERG b-wave was 28 microV in treated rats, compared with 6 microV in untreated littermates. By P83 there was still significant preservation of the ONL in treated rats. Immunoblot analysis showed a high expression of bFGF in the treated retinas even 2 months after treatment. Illumination of P23H rats at P28 with 120 fc white light for 10 hours caused substantial photoreceptor cell death, although bFGF expression was upregulated. Lowered illumination dosages continued to cause photoreceptor damage until levels were reached that neither caused damage nor enhanced survival. CONCLUSIONS: Although light stress promotes photoreceptor survival and function in the RCS rat, it elicits death signals in the P23H rats that may not be overcome by survival-promoting factors. Therefore, use of light stress to promote photoreceptor survival should be considered with regard to sensitivity of the mutation to light damage.


Assuntos
Luz , Mutação , Células Fotorreceptoras de Vertebrados/efeitos da radiação , Lesões Experimentais por Radiação/prevenção & controle , Degeneração Retiniana/prevenção & controle , Opsinas de Bastonetes/genética , Estresse Fisiológico/prevenção & controle , Animais , Animais Geneticamente Modificados , Sobrevivência Celular , Eletroforese em Gel de Poliacrilamida , Eletrorretinografia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Immunoblotting , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/ultraestrutura , Lesões Experimentais por Radiação/genética , Lesões Experimentais por Radiação/patologia , Ratos , Ratos Mutantes , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Opsinas de Bastonetes/metabolismo
20.
Brain Res ; 884(1--2): 13-22, 2000 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-11082482

RESUMO

Dopamine metabolism was studied in dystrophic retinal degeneration slow (rds) mice which carry a mutation in the rds/peripherin gene. RDS mutations in humans cause several forms of retinal degeneration. Dopamine synthesis and utilization were analyzed at various time points in the diurnal cycle in homozygous rds/rds retinas which lack photoreceptor outer segments and heterozygous rds/+ retinas which have short malformed outer segments. Homozygous retinas exhibited depressed dopamine synthesis and utilization while the heterozygous retina retained a considerable level of activity which was, nevertheless, significantly lower than that of normal retinas. By one year, heterozygous rds/+ retinas which had lost half of the photoreceptors still maintained significant levels of dopamine metabolism. Normal characteristics of dopamine metabolism such as a spike in dopamine utilization at light onset were observed in mutant retinas. However, light intensity-dependent changes in dopamine utilization were observed in normal but not rds/+ retinas. The findings of this study suggest that human patients with peripherin/rds mutations, or other mutations that result in abnormal outer segments that can still capture light, might maintain light-evoked dopamine metabolism and dopamine-dependent retinal functions during the progression of the disease, proportional to remaining levels of light capture capabilities. However, visual deficits due to reduced light-evoked dopamine metabolism and abnormal patterns of dopamine utilization could be expected in such diseased retinas.


Assuntos
Ritmo Circadiano/fisiologia , Dopamina/metabolismo , Proteínas de Filamentos Intermediários/genética , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso/genética , Retina/metabolismo , Retinose Pigmentar/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Fatores Etários , Animais , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Heterozigoto , Homozigoto , Humanos , Hidrazinas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes/metabolismo , Periferinas , Fenótipo , Estimulação Luminosa , Células Fotorreceptoras/patologia , Células Fotorreceptoras/ultraestrutura , Retina/patologia , Retina/fisiopatologia , Retinose Pigmentar/genética , Retinose Pigmentar/patologia
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