RESUMO
Although company ownership (local vs. foreign) has been used as a contingency variable that differentiates companies' environmental activities and performance, the current understanding of these differences is fragmented. None of the previous studies examined the relationships between company ownership and a complex set of organizational practices which promote employees' pro-environmental behaviors. The article fills the gap in previous research by analyzing the extent to which a total of 37 organizational practices are used. These practices are divided into technical (20 are related to environmental management) and "soft" (17 are related to HRM policies). For this study, both literature studies and a survey covering 199 companies located in Poland were used. In the theoretical part, the paper presents various typologies of factors that enhance employees' green behavior, with the focus on organizational practices. There is also a review of studies on environmental sustainability which used company ownership as a variable. The results of the empirical research show that-although in foreign companies environmental issues are increasingly perceived as important or very important-many of the practices which are treated as crucial for developing employees' eco-friendly behaviors are rarely used in both local and foreign companies. Moreover, company ownership was important in the context of using 88% of the "soft" practices and 50% of the technical practices discussed in the article. The article provides implications for policy and practice, as well as directions for further research.
Assuntos
PropriedadeRESUMO
INTRODUCTION: There is a growing number of publications highlighting sarcopenia and myosteatosis as poor prognosic factors for treatment results in oncological patients. The decrease in the cross-sectional area (CSA) of the multifidus muscle and muscle steatosis is associated with lumbar disc herniation and low back/limb pain. Nevertheless, no studies have analyzed the influence of the above parameters on patient satisfaction, pain decrease and return to daily activities. The aim of the study was to verify whether decreased preoperative CSA of the paraspinal and psoas major muscles and their fatty degeneration (myosteatosis) may influence the outcome of surgical treatment of lumbar disc disease (LDD). MATERIALS AND METHODS: One hundred and one patients with LDD undergoing open microdiscectomy were enrolled in the analysis. Relative cross-sectional areas (rCSA) of the paraspinal and psoas major muscles as well as their fatty degeneration were measured. Patients were assessed according to the validated Polish versions of the EURO EQ-5D, Core Outcome Measure Index (COMI), Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) 1 and 6 months postoperatively. The association between the variables was calculated using Pearson r and Spearman rank correlation. The Kruskal-Wallis test was used to compare the results between the groups with different rCSA of paraspinal and psoas major muscles and a different degree of paraspinal muscle myosteatosis. RESULTS: Fatty degeneration of the paraspinal muscles correlated with better outcomes 1 and 6 months postoperatively according to ODI (P = 0.003 and P = 0.027, respectively). Patients with higher rCSA of the paraspinal and psoas major muscles achieved better results on the EURO EQ-5D scale (P = 0.0289 and P = 0.0089, respectively). Higher rCSA of the paraspinal and psoas major muscles did not correlate with better outcomes measured using ODI, COMI and VAS scales (P ≥ 0.072). CONCLUSION: The degree of fatty degeneration of the paraspinal muscles correlates with better outcomes 1 and 6 months after microdiscectomy.
Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Dor Lombar , Humanos , Degeneração do Disco Intervertebral/complicações , Degeneração do Disco Intervertebral/cirurgia , Dor Lombar/etiologia , Dor Lombar/cirurgia , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética/métodos , Atrofia Muscular/etiologia , Músculos ParaespinaisRESUMO
OBJECTIVE: The aim of the study was to determine the stability of two non-commercially produced solutions: 1.68% sodium bicarbonate in 5% glucose (BIC solution) and 1.6% calcium chloride in 0.9% sodium chloride (CAL solution), which can be used to treat tumor lysis syndrome. One of the ways to treat the tumor lysis syndrome is to irrigate patients, alkalinize the urine through the supply of BIC solution or continuous hemodialysis with regional citrate anticoagulation, using a CAL solution. METHOD: The study took place in two independent hospital pharmacies. Fifty samples of each solution were prepared under aseptic conditions, then the concentration of sodium and calcium ions was determined and microbiological purity tests were carried out. The tests were performed on the day of sample preparation and after seven days of storage at 4 ± 1â. RESULTS: The obtained results showed that applied preparation method was precise and accuracy. The average concentration of sodium ions in BIC solutions ranged from 187.7 to 185.26 mmol/L on 1st and 7th day, respectively. The average concentration of calcium ions in CAL solution ranged from 68.92 to 68.80 mmol/L on 1st and 7th day, respectively. None of the samples were microbiologically contaminated. CONCLUSION: Studied solutions for infusion were characterized by good chemical and microbiological stability when prepared in a clean room and stored at 4 ± 1â.
Assuntos
Cloreto de Cálcio/química , Glucose/química , Bicarbonato de Sódio/química , Cloreto de Sódio/química , Composição de Medicamentos , Contaminação de Medicamentos , Estabilidade de Medicamentos , Humanos , Infusões Parenterais , Soluções Farmacêuticas , Soluções , Síndrome de Lise Tumoral/tratamento farmacológicoRESUMO
PURPOSE: Arteriovenous malformations (AVMs) are connected with cerebral haemorrhage, seizures, increased intracranial pressure, headaches, mass effect, and ischaemia symptoms. Selection of the best treatment method or even deciding if intervention is required can be difficult. MATERIAL AND METHODS: The study included 50 patients who were diagnosed with cerebral AVMs and treated in our Centre between 2008 and 2014. A total of 111 procedures were performed, including 94 endovascular embolisations and 17 neurosurgical procedures. Medical records and imaging data were reviewed for all patients. All AVMs were measured and assessed, allowing classification in Spetzler-Martin and Spetzler-Ponce scales. RESULTS: Complete or partial treatment was observed in 88.24% of neurosurgical procedures and in 84.00% of embolisations. Early complication rate was 21.28% for embolisation and 17.65% for neurosurgical procedures, while Glasgow Outcome Scale was 4.89 (σ = 0.38) and 5.0 (σ = 0.00), respectively. According to the Spetzler-Martin scale, cerebral haemorrhages occurred more frequently in grade 1, but no statistical significance was observed. In Spetzler-Ponce class B lower grades in Glasgow Coma Scale (GCS) were noticed (p = 0.02). Lower GCS scores were also correlated with deep location of AVM and with eloquence of adjacent brain. Patients with Spetzler-Martin grade 1 were more frequently qualified for neurosurgical procedures than other patients. CONCLUSIONS: Treating AVMs requires coordination of a multidisciplinary team. Both endovascular embolisation and neurosurgical procedure should be considered as a part of multimodal, frequently multistage treatment. Spetzler-Martin and Spetzler-Ponce scales have an influence on haemorrhage frequency and patients' clinical condition and should be taken into consideration in selecting the treatment method.
Assuntos
Anafilaxia/tratamento farmacológico , Antialérgicos/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Venenos de Artrópodes/efeitos adversos , Venenos de Artrópodes/imunologia , Criança , Estudos de Coortes , Feminino , Humanos , Himenópteros/imunologia , Mordeduras e Picadas de Insetos/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
The Lewis acid mediated intramolecular Nicholas reactions of allylic acetate enyne-Co2(CO)6 complexes afford cycloheptenyne-Co2(CO)6 complexes in three manifestations. Electron rich aryl substituted alkyne complexes give tricyclic 6,7,x-benzocycloheptenyne complexes, with x = 5, 6, or 7. Allylsilane substituted complexes afford exo methylene bicyclic x,7-cycloheptenyne complexes (x = 6,7). The allyl acetate function may also be replaced by a benzylic acetate, to afford dibenzocycloheptyne-Co2(CO)6 complexes. Following reductive complexation, the methodology may be applied to the synthesis of the icetexane diterpene carbon framework.
RESUMO
Vimentin is an intermediate filament protein normally expressed in cells of mesenchymal origin, e.g. myofibroblasts, chondrocytes, macrophages, and endothelial cells. The expression of vimentin, which has been thought of as the main mesenchymal marker, is also detected in tumour tissue. In tumours of the gastrointestinal tract vimentin expression is usually correlated with advanced stage of tumour, lymph node metastasis, and patient survival.
RESUMO
PURPOSE Perivascular epithelioid cell tumors (PEComas) represent a family of mesenchymal neoplasms, mechanistically linked through activation of the mTOR signaling pathway. There is no known effective therapy for PEComa, and the molecular pathophysiology of aberrant mTOR signaling provided us with a scientific rationale to target this pathway therapeutically. On this mechanistic basis, we treated three consecutive patients with metastatic PEComa with an oral mTOR inhibitor, sirolimus. PATIENTS AND METHODS Patients with advanced PEComa were treated with sirolimus and consented to retrospective collection of data from their medical records and analysis of archival tumor specimens. Tumor response was determined by computed tomography scans obtained at the clinical discretion of the treating physicians. Tumors were assessed for immunohistochemical evidence of mTORC1 activation and genetic evidence of alterations in TSC1 and TSC2. Results Radiographic responses to sirolimus were observed in all patients. PEComas demonstrated loss of TSC2 protein expression and evidence of baseline mTORC1 activation. Homozygous loss of TSC1 was identified in one PEComa. CONCLUSION Inhibition of mTORC1, pathologically activated by loss of the TSC1/TSC2 tumor suppressor complex, is a rational mechanistic target for therapy in PEComas. The clinical activity of sirolimus in PEComa additionally strengthens the pathobiologic similarities linking PEComas to other neoplasms related to the tuberous sclerosis complex.
Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Neoplasias de Células Epitelioides Perivasculares/tratamento farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Sirolimo/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Administração Oral , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/efeitos adversos , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Peptídeos e Proteínas de Sinalização Intracelular/análise , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Pessoa de Meia-Idade , Complexos Multiproteicos , Neoplasias de Células Epitelioides Perivasculares/química , Neoplasias de Células Epitelioides Perivasculares/diagnóstico por imagem , Neoplasias de Células Epitelioides Perivasculares/genética , Neoplasias de Células Epitelioides Perivasculares/secundário , Proteínas Serina-Treonina Quinases/análise , Proteínas , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Serina-Treonina Quinases TOR , Fatores de Tempo , Tomografia Computadorizada por Raios X , Fatores de Transcrição/análise , Resultado do Tratamento , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/análise , Proteínas Supressoras de Tumor/genética , Estados UnidosRESUMO
The receptor tyrosine kinase/PI3K/AKT/mammalian target of rapamycin (RTK/PI3K/AKT/mTOR) pathway is frequently altered in cancer, but the underlying mechanism leading to tumorigenesis by activated mTOR remains less clear. Here we show that mTOR is a positive regulator of Notch signaling in mouse and human cells, acting through induction of the STAT3/p63/Jagged signaling cascade. Furthermore, in response to differential cues from mTOR, we found that Notch served as a molecular switch to shift the balance between cell proliferation and differentiation. We determined that hyperactive mTOR signaling impaired cell differentiation of murine embryonic fibroblasts via potentiation of Notch signaling. Elevated mTOR signaling strongly correlated with enhanced Notch signaling in poorly differentiated but not in well-differentiated human breast cancers. Both human lung lymphangioleiomyomatosis (LAM) and mouse kidney tumors with hyperactive mTOR due to tumor suppressor TSC1 or TSC2 deficiency exhibited enhanced STAT3/p63/Notch signaling. Furthermore, tumorigenic potential of cells with uncontrolled mTOR signaling was suppressed by Notch inhibition. Our data therefore suggest that perturbation of cell differentiation by augmented Notch signaling might be responsible for the underdifferentiated phenotype displayed by certain tumors with an aberrantly activated RTK/PI3K/AKT/mTOR pathway. Additionally, the STAT3/p63/Notch axis may be a useful target for the treatment of cancers exhibiting hyperactive mTOR signaling.
Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Proteínas de Membrana/fisiologia , Proteínas Quinases/fisiologia , Receptores Notch/fisiologia , Fator de Transcrição STAT3/fisiologia , Transdução de Sinais/fisiologia , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Proteína Jagged-1 , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Serrate-Jagged , Serina-Treonina Quinases TOR , Fatores de Transcrição/fisiologiaRESUMO
OBJECTIVES: The aim of present work was to examine estrogen influence on neurogenesis in the model of predegenerated peripheral nerve grafts implantation into the rat hippocampal dentate gyrus. METHODS: Experiment was carried out on female rats divided into three experimental groups: NO - non-ovariectomized, OV - ovariectomized and E - heterogeneous group with various 17-beta-estradiol substitution after ovariectomy. Proliferating cells were labeled with BrdU. Brains were subjected to immunohistochemical procedures to visualize nestin, GFAP and estrogen receptors (ERalpha and ERbeta). RESULTS: Proliferation rate was highest in E groups with estrogen levels resembling that in proestrus phase. Ovariectomy resulted in higher than in NO group number of new neurons, while high hyperestrogenemia worsened the results. The proportions of nestin-labeled cells correlated in similar way with different hormonal state. We found also distinct co-localization of nestin and GFAP in E group (proestrus). It may suggest the presence of radial glia, a potential source of new neurons in adult mammals. Nerve graft induced ERalpha expression at the site of injury in all groups. Distribution of ERbeta in hippocampus was estradiol-dose-dependent and correlated with cell proliferation. CONCLUSION: In our model, 17-beta-estradiol and predegenerated nerve graft implantation had synergistic effect on hippocampal neurogenesis.
Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Hipocampo/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Animais , Proteínas de Ligação a DNA , Relação Dose-Resposta a Droga , Proteínas de Drosophila , Estradiol/sangue , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrogênios/sangue , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/fisiologia , Hipocampo/cirurgia , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nestina , Neurogênese/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ovariectomia , Distribuição Aleatória , Ratos , Ratos Wistar , Nervo Isquiático/lesões , Nervo Isquiático/transplanteRESUMO
Inactivating mutations of the tumor suppressor gene TSC2 are associated with tumorigenesis in tuberous sclerosis complex (TSC) and lymphangioleiomyomatosis. Statins, as 3-hydroxy-3-methylglutaryl CoA reductase inhibitors, have the potential to limit the growth of these tumors by limiting the isoprenylation of activated GTPases in Tsc2-null cells. We tested atorvastatin as a therapy for (a) ethylnitrosourea (ENU)-enhanced renal cystadenoma and (b) spontaneous liver hemangioma in 129Sv/Jae Tsc2(+/-) mice. ENU-treated Tsc2(+/-) mice were given atorvastatin chow (0.1%, w/w) for 1 or 3 months before sacrifice at 6 months; 129Sv/Jae Tsc2(+/-) mice were given atorvastatin chow (0.1%, w/w) for 6 months before sacrifice at 12 months. All treatment groups were compared with mice of identical genotype and strain background that were fed control chow. Pathologic analyses revealed a predominance of renal cystadenoma in ENU-treated and liver hemangioma in non-ENU-treated 129Sv/Jae Tsc2(+/-) mice. In both cohorts, serum cholesterol levels and levels of phosphorylated S6 and GTP-RhoA in healthy tissue were significantly (>50%) reduced in atorvastatin-treated mice as compared with controls. Following atorvastatin treatment, no significant reduction in tumor size, morphology, or phosphorylated S6 levels was observed for either ENU-associated renal cystadenoma or spontaneous liver hemangioma as compared with the untreated groups. In conclusion, although the marked reduction in cholesterol levels indicates that atorvastatin was effective as an 3-hydroxy-3-methylglutaryl CoA reductase inhibitor, it did not inhibit the growth of tumors that develop in these Tsc2(+/-) models, suggesting that it is unlikely to have benefit as a single-agent therapy for TSC-associated tumors.
Assuntos
Modelos Animais de Doenças , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Pirróis/uso terapêutico , Esclerose Tuberosa/patologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Atorvastatina , Colesterol/metabolismo , Cistadenoma/tratamento farmacológico , Cistadenoma/metabolismo , Cistadenoma/patologia , Feminino , Hemangioma/tratamento farmacológico , Hemangioma/metabolismo , Hemangioma/patologia , Técnicas Imunoenzimáticas , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Taxa de Sobrevida , Proteína 2 do Complexo Esclerose TuberosaRESUMO
BACKGROUND: Tuberous sclerosis (TSC) is a hamartoma syndrome in which renal and lung tumors cause the greatest morbidity. Loss of either TSC1 or TSC2 in TSC hamartomas leads to activation of mTORC1 and suppression of AKT. Recent studies indicate that inhibition of mTORC1 with RAD001 (everolimus) leads to rebound activation of AKT, which could protect tumors from drug-induced cell death. Here we examine the potential benefit of inhibition of both mTOR and AKT signaling in a mouse model of TSC, using a dual pan class I PI3K/mTOR catalytic small molecule inhibitor NVP-BEZ235. RESULTS: Using ENU to enhance Tsc2+- kidney tumor development, both RAD001 (10 mg/kg PO 5 d/week) and NVP-BEZ235 (45 mg/kg PO QD) had equivalent effects in suppressing tumor development during a 4 week treatment period, with a 99% reduction in tumor cell mass. Marked reduction in activation of mTORC1, induction of cell cycle arrest, and absence of apoptotic cell death was seen in mice treated with either drug. However, when either was discontinued, there was prompt recovery of tumor growth, with extensive proliferation. CONCLUSION: Both mTORC1 blockade alone and combined PI3K-mTOR blockade lead to suppression of tumor development but not tumor elimination in this TSC model.
Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Transporte/antagonistas & inibidores , Neoplasias Renais/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Sirolimo/análogos & derivados , Fatores de Transcrição/antagonistas & inibidores , Esclerose Tuberosa/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Proteínas de Transporte/metabolismo , Modelos Animais de Doenças , Etilnitrosoureia , Everolimo , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Neoplasias Renais/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Complexos Multiproteicos , Recidiva Local de Neoplasia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Serina-Treonina Quinases TOR , Fatores de Transcrição/metabolismo , Esclerose Tuberosa/patologiaRESUMO
Paragangliomas of the cauda equina are rare neuroepithelial tumors, usually manifesting clinically as sciatica. Here, we report a case of cauda equina paraganglioma with an unusual course in a 43-year-old man. His main complaints were erectile and sphincter dysfunction. The low back pain was initially ascribed to accidental injury. Magnetic resonance imaging revealed intradural tumor at the L2/L3 level. The patient underwent gross tumor resection, and the diagnosis of paraganglioma was based on neuropathologic examination. The symptoms completely resolved after tumor resection.
Assuntos
Cauda Equina , Disfunção Erétil/etiologia , Paraganglioma Extrassuprarrenal/complicações , Neoplasias do Sistema Nervoso Periférico/complicações , Transtornos Urinários/etiologia , Adulto , Humanos , Masculino , Paraganglioma Extrassuprarrenal/patologia , Neoplasias do Sistema Nervoso Periférico/patologiaRESUMO
Tuberous sclerosis complex (TSC) is a tumor suppressor gene syndrome in which hamartomas develop in multiple organ systems. Knockout and conditional alleles of Tsc1 and Tsc2 have been previously reported. Here, we describe the generation of a novel hypomorphic allele of Tsc2 (del3), in which exon 3, encoding 37 amino acids near the N terminus of tuberin, is deleted. Embryos homozygous for the del3 allele survive until E13.5, 2 days longer than Tsc2 null embryos. Embryos die from underdevelopment of the liver, deficient hematopoiesis, aberrant vascular development and hemorrhage. Mice that are heterozygous for the del3 allele have a markedly reduced kidney tumor burden in comparison with conventional Tsc2(+/-) mice. Murine embryo fibroblast (MEF) cultures that are homozygous for the del3 allele express mutant tuberin at low levels, and show enhanced activation of mTORC1, similar to Tsc2 null MEFs. Furthermore, the mutant cells show prominent reduction in the activation of AKT. Similar findings were made in the analysis of homozygous del3 embryo lysates. Tsc2-del3 demonstrates GTPase activating protein activity comparable to that of wild-type Tsc2 in a functional assay. These findings indicate that the del3 allele is a hypomorphic allele of Tsc2 with partial function due to reduced expression, and highlight the consistency of AKT downregulation when Tsc1/Tsc2 function is reduced. Tsc2-del3 mice also serve as a model for hypomorphic TSC2 missense mutations reported in TSC patients.
Assuntos
Modelos Animais de Doenças , Hamartoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Alelos , Animais , Linhagem Celular , Éxons , Feminino , Deleção de Genes , Hamartoma/embriologia , Hamartoma/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/genética , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose TuberosaRESUMO
The presence of stem cells differentiating to hepatocytes and cholangiocytes has been previously reported in livers of young rats. Here, we have isolated, cultured, and characterized mesenchymal stem cells (MSCs) from livers of young and old rats and tested their multipotential for differentiation. The mesenchymal stem cells in liver sections were identified by the presence of markers, respectively for primary stem cells Thy-1 and CD34, for differentiation to early cholangiocytes GST and CK19, and for differentiation to hepatocytes GSTalpha and CK18. Ki67 was detected as the cell proliferation marker. Cells isolated from livers of either age group were tested in a culture for their viability following storage and were characterized for the presence of most of the markers detected in cells in situ. The results revealed age-dependent changes in the number of recovered primary MSCs. In both age groups we have observed cells changing under differentiating conditions to liver cell lineages, such as cholangiocytes and hepatocytes, as well as to non-liver cells such as adipocytes, astrocytes, neuroblasts, and osteoblasts. Our data revealed that from the livers of rats 20 months and older the primary MSCs could be isolated and expanded; however, they were significantly fewer, even though their differentiation multipotential was preserved. The mechanism involved in the differentiation of liver MSCs seemed to depend on a constellation of signals in Notch signalling pathways. Thus, our results support the idea of potential use of liver as a source of MSCs, not only for liver reconstruction but also for cell therapy in general.
Assuntos
Diferenciação Celular/fisiologia , Fígado/citologia , Células-Tronco Mesenquimais/citologia , Fatores Etários , Animais , Células Cultivadas , Hepatócitos/citologia , Ratos , Ratos Sprague-DawleyRESUMO
Ghrelin is produced mainly in the stomach and is an essential link of the brain-gut axis. Ghrelin stimulates hunger centers in hypothalamus controlling food intake and body mass gain. The aim of the study is to analyze the total ghrelin plasma level in patients suffering from restrictive type of anorexia nervosa (AN-R). According to DSM-IV classification a group of 30 AN-R patients was investigated before and after 3 and 6 months of therapy. Therapy included normocaloric diet and cognitive-behavioral psychotherapy (CBT). The control group consisted of 20 girls without any eating disorders. Before the therapy the total ghrelin plasma level in AN-R patients was significantly higher than in the control group. After 3 and 6 months of treatment the total ghrelin plasma level in AN-R patients was significantly lower than in the control group. In AN-R patients, the total ghrelin plasma level is connected with the pathological feeding behavior.
Assuntos
Anorexia Nervosa/sangue , Hormônios Peptídicos/sangue , Adolescente , Adulto , Anorexia Nervosa/dietoterapia , Anorexia Nervosa/terapia , Índice de Massa Corporal , Transtornos da Alimentação e da Ingestão de Alimentos/sangue , Feminino , Grelina , HumanosRESUMO
Current methods of peripheral nerve repair are to rejoin cut nerve stumps directly or to bridge large gaps with autologous nerve grafts. In both cases the surface of nerve stump endings is typically cut perpendicularly to the long axis of the nerve. The outcome of such operations, however, is still not satisfactory. In this study, we examine the effect of oblique nerve cutting and grafting on morphological as well as functional features of regeneration. In adult rats, sciatic nerve was cut and rejoined either directly or using an autologous graft, at 90 degrees or 30 degrees angle. Functional regeneration was assessed by walking track analysis during 12-week follow-up. Afterwards muscle weight was measured and histological studies were performed. The latter included nerve fibers and Schwann cells counting, as well as visualization of scar formation and epineural fibrosis. Nerves cut obliquely and rejoined showed better functional recovery than perpendicularly transected. Similar effect was observed after oblique grafting when compared to perpendicular one. Numbers of nerve fibers growing into the distal stump of the nerve as well as the number of Schwann cells were significantly higher in obliquely than in perpendicularly operated nerves. Moreover, growing axons were arranged more regularly following oblique treatment. These data indicate that joining or grafting the nerve stumps at acute angle is a more profitable method of nerve repair than the standard procedure performed at right angle.
Assuntos
Regeneração Nervosa/fisiologia , Nervo Isquiático/fisiopatologia , Nervo Isquiático/transplante , Coleta de Tecidos e Órgãos/métodos , Animais , Adesivo Tecidual de Fibrina/uso terapêutico , Masculino , Ratos , Ratos Wistar , Recuperação de Função Fisiológica/fisiologia , Nervo Isquiático/patologia , Técnicas de Sutura , Adesivos Teciduais/uso terapêutico , Transplante AutólogoRESUMO
The Bcl family contains both pro and antiapoptotic proteins participating in the regulation of neuronal cell death in several pathological conditions. However, very little is known about physiological profiles of Bcl-2/Bax expression in normal brain. In this study, we examined expression profile of Bcl-2 and Bax proteins in normal pineal gland in children. The material for analysis was obtained by biopsy of pineal parenchyma during surgery of pineal cysts. All specimens were labeled immunohistochemically and analyzed by means of confocal laser scanning microscope. We found only few Bcl-2 expressing (0.7%) and no Bax-immunopositive (0.0%) pinealocytes. Bcl-2-positive cells were mature neurons, neither young ones nor glia.
Assuntos
Glândula Pineal/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Adolescente , Biomarcadores/metabolismo , Biópsia , Encefalopatias/patologia , Encefalopatias/cirurgia , Criança , Cistos/patologia , Cistos/cirurgia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Masculino , Neurônios/citologia , Neurônios/metabolismo , Glândula Pineal/citologiaRESUMO
Estrogens are pleiotropic hormones having an influence not only on reproductive system and sexual functions. These hormones are synthesized not only by ovaries, but also by glia in central nervous system (CNS) and Schwann cells in peripheral nervous system. Therefore they create microenvironment having a wide spectrum of effects such as neuroprotective and antiapoptotic or supporting neurogenesis and regeneration. Mechanisms of estrogens activity are both genomic and quick non-genomic transmitted through second intracellular messengers. There is evidence for protective action of estrogens in neurodegenerative diseases and other diseases of CNS. Nevertheless there are still secrets in estrogens nature. This fact pushes us to ask more questions and continue scientific research to look for the answer.