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1.
J Phys Ther Sci ; 35(8): 575-580, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37529062

RESUMO

[Purpose] This study aimed to examine the impact of physiotherapy on various patients who underwent hybrid closed-wedge high tibial osteotomy. [Participants and Methods] Eighty-four patients were divided into three groups: non-weight-bearing, enhanced recovery after surgery, and grouping exercise. The number of hospital days, distinctions in the duration of cane-walking independence, and postoperative complications were compared among the three groups. Furthermore, the Japanese Orthopaedic Association score and physical function were assessed preoperatively and at 3 and 12 months postoperatively. [Results] There were no considerable differences in postoperative complications among the three groups, and the mean hospital stay was the shortest for the grouping exercise group. At 3 months postoperatively, the grouping exercise group reported less walking pain than the enhanced recovery after surgery group. At 3 and 12 months postoperatively, the grouping exercise group showed greater mean knee extensor strength and a higher mean Japanese Orthopaedic Association score than the non-weight-bearing group. [Conclusion] Grouping exercise therapy, in addition to enhanced recovery after surgery protocol, results in shorter hospital stays, no difference in postoperative complications, and good clinical outcomes.

2.
Gan To Kagaku Ryoho ; 49(13): 1524-1527, 2022 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-36733123

RESUMO

Sarcopenia is a syndrome characterized by progressive and generalized loss of skeletal muscle mass, loss of muscle strength and/or reduced physical performance. Sarcopenia has repeatedly been reported as a strong predictor of both short- and long-term outcomes following surgical treatment for colorectal cancer. In this study, 86 primary colorectal cancer cases who received surgery at our hospital were examined. To evaluate which factor amongst muscle volume, muscle strength or physical performance would be important to avoid sarcopenia after surgery, we examined objective values of muscle volume, muscle strength and physical performance respectively. We also divided patients into groups by their ages or procedures of surgeries, then compared and analyzed within those groups. The results showed that most patients tended to lose their muscle volume of their legs and their physical performance after their surgeries. We also found patients who were equal or older than 75-year-old and patients who received open surgeries tended to lose their muscle volume or physical performance after their surgeries. These groups of patients have a potential risk to turn sarcopenia after surgeries. It would be important to observe each of 3 factors such as skeletal muscle volume, muscle strength and physical performance to evaluate precisely their condition of sarcopenia. Tailor-made peri-operative rehabilitation programs, especially for elderly patients or patients who received open surgeries, would be a possible solution to avoid sarcopenia after surgery for colorectal cancer.


Assuntos
Neoplasias Colorretais , Sarcopenia , Humanos , Idoso , Sarcopenia/etiologia , Músculo Esquelético , Período Perioperatório , Neoplasias Colorretais/cirurgia
3.
Gan To Kagaku Ryoho ; 48(13): 1950-1953, 2021 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-35045457

RESUMO

Sarcopenia is a syndrome characterized by progressive and generalized loss of skeletal muscle mass, strength and function. Sarcopenia has repeatedly been reported as a strong predictor of both short- and long-term outcomes following surgical treatment for breast cancer. In this study, 41 primary breast cancer cases who received surgery at our hospital were examined. To evaluate which factor amongst muscle volume, power or function would be most important to avoid sarcopenia after surgery, we examined muscle volume, power and function respectively. We also divided patients into groups by their ages or procedures of surgeries, then compared and analyzed within those groups. The results showed their grip power of the same side of their breast cancer and muscle volume of their legs has been decreased after surgeries. We also found patients who were equal or older than 75 years old and patients who received total mastectomy tended to lose their muscle volume or muscle power after their surgeries. These groups of patients would have potential risk to become sarcopenia after surgeries. It would be important to observe each of 3 factors, skeletal muscle volume, power and function to evaluate precisely their condition of sarcopenia. Tailor-made peri-operative rehabilitation programs, especially for elderly patients or patients who received total mastectomy, would be a possible solution to avoid sarcopenia after surgery for breast cancer.


Assuntos
Neoplasias da Mama , Sarcopenia , Idoso , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia , Músculo Esquelético , Período Perioperatório , Sarcopenia/etiologia
4.
Gan To Kagaku Ryoho ; 47(13): 2098-2100, 2020 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-33468813

RESUMO

The number of elderly breast cancer patients has been increasing recently nevertheless the optimal treatment for the elderly breast cancer patients still remains controversial. In this study, 21 primary breast cancer cases who were equal or older than 85 years old at our hospital were examined their clinical and pathological features. These 21 cases were divided into 2 group; Group A; ten cases who received operations, Group B; eleven cases who did not receive operations. T categories, M categories and clinical stages in Group B were significantly higher than those of Group A. The main causing reason why Group B cases had not received operations was that their primary breast cancer were too advanced to perform operation. Instead of operation, most Group B cases received endocrine therapy or radiotherapy. Group A cases received standard operative procedures including partial or total mastectomy and biopsies or dissection of axillary lymph nodes. Besides, their post- operative courses were good and safe. These results suggest that even for elderly patients, early diagnosis and treatment could improve their prognosis and quality of life. In addition, careful surveillances for elderly breast cancer patients, those who tend to stop attending regular check up to their hospital, should be considered for further assessment for characteristics of elderly breast cancer patients.


Assuntos
Neoplasias da Mama , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/cirurgia , Neoplasias da Mama/terapia , Humanos , Mastectomia , Prognóstico , Qualidade de Vida
6.
J Toxicol Pathol ; 32(3): 165-180, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31404398

RESUMO

Hypothyroidism during the developmental stage induces disruption of hippocampal neurogenesis in later life, as well as inducing oxidative stress in the brain. The present study investigated the preventive effect of co-exposure to an antioxidant on disruptive neurogenesis induced by developmental exposure to anti-thyroid agent in rats. For this purpose, we used two antioxidants, α-glycosyl isoquercitrin (AGIQ) and α-lipoic acid (ALA). Mated female Sprague Dawley rats were either untreated (control) or treated with 12 ppm 6-propyl-2-thiouracil (PTU), an anti-thyroid agent, in drinking water from gestational day 6 to postnatal day (PND) 21, the latter group being subjected to feeding basal diet alone or diet containing AGIQ at 5,000 ppm or ALA at 2,000 ppm during PTU exposure. On PND 21, PTU-exposed offspring showed reductions in a broad range of granule cell lineage subpopulations and a change in the number of GABAergic interneuron subpopulations. Co-exposure of AGIQ or ALA with PTU altered the transcript levels of many genes across multiple functions, suggestive of enhancement of synaptic plasticity and neurogenesis. Nevertheless, immunohistochemical results did not support these changes. PTU exposure and co-exposure of AGIQ or ALA with PTU did not alter the hippocampal lipid peroxidation level. The obtained results suggest a possibility that thyroid hormone depletion itself primarily disrupts neurogenesis and that oxidative stress may not be involved in the disruption during development. Transcript expression changes of many genes caused by antioxidants may be the result of neuroprotective actions of antioxidants rather than their antioxidant activity. However, no preventive effect on neurogenesis suggested impairment of protein synthesis via an effect on mRNA translation due to hypothyroidism.

7.
World Neurosurg ; 130: 71-76, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31279920

RESUMO

BACKGROUND: Cerebellar cyst formation after surgery is uncommon, and few cases of this condition have been previously reported. These cases had an intraparenchymal cyst in the cerebellar hemisphere that required surgical fenestration of the cyst. We herein present a rare case of a postoperative cerebellar cyst with pseudomeningocele and magnetic resonance images indicating a fistula between the cyst and pseudomeningocele. CASE DESCRIPTION: A patient presented with an intraparenchymal cyst and surrounding edema in the cerebellar hemisphere that developed after a C1 laminectomy and a small suboccipital craniectomy for the removal of an accessory nerve neurinoma at the craniovertebral junction. Fast imaging employing steady-state acquisition images identified the fistula connecting the cyst and extradural cerebrospinal fluid retention. Conservative management with administration of dexamethasone induced spontaneous regression of the cyst, and no recurrence had occurred by the 1-year follow-up. CONCLUSIONS: Watertight dural closure is important for the prevention of this rare complication after posterior fossa surgery. However, an arachnoid tear on the cerebellar fissure and adjacent dural defect are necessary antecedents for this rare condition. High-resolution fast imaging employing steady-state acquisition images could provide additional information for the etiology of postoperative cerebellar cyst.


Assuntos
Cistos do Sistema Nervoso Central/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Meningocele/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/cirurgia , Idoso , Cistos do Sistema Nervoso Central/etiologia , Vértebras Cervicais/diagnóstico por imagem , Humanos , Masculino , Meningocele/etiologia , Complicações Pós-Operatórias/etiologia , Base do Crânio/diagnóstico por imagem
8.
J Vet Med Sci ; 81(8): 1229-1233, 2019 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-31270282

RESUMO

A female koala presented with hyperglycemia related to diabetes mellitus diagnosed at 9 years and treated with insulin. She presented with nasal hemorrhage, anemia, leukocytosis, and tachypnea at 10 years. A blood smear examination revealed scattered, atypical large myeloid cells and a clinical diagnosis of myelogenous leukemia was made. White blood cell count reached a maximum of 295 × 102/µl, with evidence of severe regenerative anemia and thrombocytopenia. Grossly, systemic lymph node enlargement, fragile liver with hemorrhage, and bloody ascites were observed. Histopathologically, atypical myeloid cells, including myelocytic and metamyelocytic cells, were scattered in the vasculature and surrounding tissues throughout the organs. The patient was infected with a koala retrovirus, which might have caused the myelogenous leukemia.


Assuntos
Complicações do Diabetes/veterinária , Diabetes Mellitus/veterinária , Leucemia Mieloide Aguda/veterinária , Phascolarctidae , Infecções por Retroviridae/veterinária , Animais , Complicações do Diabetes/diagnóstico , Complicações do Diabetes/patologia , Complicações do Diabetes/virologia , Feminino , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/virologia , Phascolarctidae/virologia , Infecções por Retroviridae/complicações
9.
Gan To Kagaku Ryoho ; 46(13): 1996-1998, 2019 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-32157038

RESUMO

A nomogram is a statistical tool that can provide the specific outcomes of individual patients. In this study, we used a nomogram developed by Beppu et al to evaluate the prognoses of 38 patients who underwent hepaticresec tion at our hospital. This nomogram predicts disease-free survival(DFS)after hepatic resection for colorectal liver metastasis based on 6 clinical and oncological factors. Using this nomogram, we divided the 38 patients into 3 groups: Group N, actual DFS was almost similar to the estimated median DFS(EMDFS)provided by the nomogram; Group A, DFS was longer than EMDFS; and Group B, DFS was shorter than EMDFS. Then, we compared and analyzed clinical and oncological factors between Groups A and B. Group B patients tended to have single metastasis and non-normal levels of CA19-9. Besides, Group B patients had DFS shorter than approximately 2 years. These results suggest that if CA19-9 levels are not normalized after hepaticresec tion for single metastasis, we should consider careful observation and adjuvant chemotherapy for potential micrometastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Intervalo Livre de Doença , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Nomogramas , Prognóstico , Estudos Retrospectivos
10.
Toxicol Sci ; 159(1): 211-223, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28903497

RESUMO

We previously observed downregulation of mitochondrial oxidative phosphorylation-related protein, TMEM70, which is suggestive of disrupted cellular senescence, in GST-P-expressing (+) proliferative lesions from early hepatocarcinogenesis stages in rats. The present study investigated the immunohistochemical relationship between TMEM70 downregulation and cellular metabolic changes in carcinogenic processes, as well as the onset of the liver cell respiratory changes after repeated hepatocarcinogen treatment in rats. At the early hepatocarcinogenesis stage in a 2-stage model, GST-P+ preneoplastic lesions showing TMEM70 downregulation also downregulated the mitochondrial ATPase, ATPB, but upregulated glycolysis-related glucose transporter member 1 (GLUT1) and glucose-6-phosphate dehydrogenase, suggesting a metabolic shift from oxidative phosphorylation to glycolysis, known as the Warburg effect. Combined downregulation of TMEM70 and ATPB increased proliferation activity in GST-P+ preneoplastic lesions, suggesting cell proliferation facilitation by reducing mitochondrial respiration. Concurrent GLUT1-upregulation and TMEM70-downregulation increased nuclear phosphorylated c-MYC+ cells in GST-P+ preneoplastic lesions, suggesting c-MYC-mediated transcription facilitation to promote glycolysis and cell proliferation. The TMEM70-related metabolic shift was enhanced in GST-P+ neoplastic lesions, suggesting a contribution to tumor progression. Conversely, the TMEM70-related metabolic shift was lacking in peroxisome proliferator-activated receptor-α agonist-induced hepatocarcinogenesis, as well as in carcinogenic processes targeting other organs. Transcript expression analysis following 28- and 90-day repeated hepatocarcinogen treatment showed downregulation of Tmem70 from day 28 and upregulation of Pkm and Myc at day 90, suggesting early onset of a catastrophic cellular senescence-related metabolic shift beginning from depressed mitochondrial respiration in the liver. These results suggest a contribution of TMEM70 downregulation to the Warburg effect, which directs tumor promotion and progression in GST-P+-linked hepatocarcinogenesis in rats.


Assuntos
Carcinógenos/toxicidade , Regulação para Baixo , Glutationa S-Transferase pi/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Fígado/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Oxigênio/metabolismo , Animais , Apoptose , Proliferação de Células , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Fosforilação Oxidativa , Ratos
11.
Toxicol Appl Pharmacol ; 334: 207-216, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28899750

RESUMO

We previously found downregulation of ubiquitin-conjugating enzyme E2E 2 (UBE2E2) in GST-P-positive (+) proliferative lesions produced by tumor promotion from early hepatocarcinogenesis stages in rats. Here we investigated the role of UBE2E2 downregulation in preneoplastic lesions of the liver and other target organs produced by tumor promotion in rats. Increased number of UBE2E2-related ubiquitination target proteins, phosphorylated c-MYC, KDM4A and KMT5A, was found in the UBE2E2-downregulated GST-P+ foci, compared with GST-P+ foci expressing UBE2E2. However, p21WAF1/CIP1, another UBE2E2 target protein, did not increase in the positive cells. Furthermore, the numbers of PCNA+ cells and γH2AX+ cells were increased in UBE2E2-downregulated foci. These results suggest sustained activation of c-MYC and stabilization of KMT5A to result in c-MYC-mediated transcript upregulation and following KMT5A-mediated protein stabilization of PCNA in GST-P+ foci, as well as KDM4A stabilization resulting in slowing down of DNA damage response in these lesions. Similar results were also observed in GST-P+ foci produced by repeated treatment of rats with a hepatocarcinogen, thioacetamide, for 90days. Hepatocarcinogen treatment for 28 or 90days also increased the numbers of liver cells expressing UBE2E2-related ubiquitination target proteins, as well as PCNA+ or γH2AX+ cells. Conversely, UBE2E2 downregulation was lacking in PPARα agonist-induced hepatocarcinogenesis, as well as in carcinogenic processes targeting other organs, suggestive of the loss of UBE2E2-related ubiquitination limited to hepatocarcinogenesis producing GST-P+ proliferative lesions. Our results suggest that repeated hepatocarcinogen treatment of rats causes stabilization of UBE2E2-related ubiquitination target proteins in liver cells to promote carcinogenesis.


Assuntos
Carcinógenos/toxicidade , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Glutationa S-Transferase pi/metabolismo , Hepatócitos/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Animais , Apoptose , Reparo do DNA , Regulação para Baixo , Regulação da Expressão Gênica , Glutationa S-Transferase pi/genética , Lesões Pré-Cancerosas/induzido quimicamente , Distribuição Aleatória , Ratos , Ubiquitina-Proteína Ligases/genética
12.
Neurotox Res ; 32(1): 27-40, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28168441

RESUMO

The effects of developmental exposure to 3,3'-iminodipropionitrile (IDPN), a neurotoxicant that causes proximal axonopathy, on mouse hippocampal neurogenesis was examined. Pregnant mice were exposed to IDPN at 0, 600, or 1200 ppm in their drinking water from gestational day 6 to postnatal day (PND) 21. On PND 21, male offspring showed increased postmitotic neuron-specific NeuN-immunoreactive(+) granule cell numbers in the dentate subgranular zone (SGZ) and granule cell layer (GCL) and decreased glutamate receptor gene Grin2d levels in the dentate gyrus at 1200 ppm. On PND 77, decreased numbers were observed for TBR2+ progenitor cells in the SGZ at ≥600 ppm and GFAP+ stem cells, DCX+ progenitor cells and immature granule cells, NeuN+ immature and mature granule cells, PCNA+ proliferating cells in the SGZ and/or GCL, and immunoreactive cells for ARC or FOS, immediate-early gene products related to neuronal and synaptic plasticity, in the GCL at 1200 ppm. Additionally, at 1200 ppm of IDPN, downregulation of Kit, the gene encoding the stem cell factor (SCF) receptor, and upregulation of Kitl, encoding SCF, were observed in the dentate gyrus. Therefore, maternal IDPN exposure in mice affects neurogenesis involving glutamatergic signals at the end of developmental exposure, with late effects suppressing SGZ cell proliferation, reducing the broad range of granule cell lineage population, which may be responsible for SCF receptor downregulation. The upregulated SCF was likely a feedback response to the decreased receptor level. These results suggest that reduced SCF signaling may cause suppressed neuronal and synaptic plasticity.


Assuntos
Giro Denteado , Neurogênese/efeitos dos fármacos , Nitrilas/farmacologia , Fatores Etários , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Giro Denteado/citologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/embriologia , Giro Denteado/crescimento & desenvolvimento , Proteína Duplacortina , Embrião de Mamíferos , Proteína 7 de Ligação a Ácidos Graxos/genética , Proteína 7 de Ligação a Ácidos Graxos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Necrose/induzido quimicamente , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Oncogênicas v-fos/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo
13.
Toxicol Lett ; 266: 13-22, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914986

RESUMO

The present study identified genes showing promoter region hypermethylation by CpG island microarrays in the liver of rats treated with hepatocarcinogen thioacetamide (TAA) for 28days. Among 47 hypermethylated genes, Hist1h2aa, Tmem70, Ube2e2, and Slk were confirmed to show hypermethylation by methylation-specific quantitative polymerase chain reaction (PCR) and pyrosequencing analyses as well as downregulation of transcript levels by real-time reverse transcription-PCR analysis in the livers of rats treated with TAA. All gene products of the 4 selected genes showed decreased immunoreactivity forming negative liver cell foci in a subpopulation of glutathione S-transferase placental form (GST-P)+ foci in TAA-promoted rat livers in a two-stage hepatocarcinogenesis model. Among them, TMEM70 and UBE2E2 showed increased incidences of negative foci in GST-P+ foci by promotion of all examined TAA, ß-naphthoflavone, piperonyl butoxide, fenbendazole and phenobarbital, while HIST1H2AA and SLK did not respond to all promotive treatments. In the late stage of tumor promotion by TAA, the incidence of GST-P+ proliferative lesions with downregulation of TMEM70 or UBE2E2 was higher in adenomas and carcinomas than liver cell foci. TMEM70 plays a role in mitochondrial oxidative phosphorylation, and UBE2E2 participates in the stabilization of cell cycle regulatory proteins. Therefore, our results indicate that aberrant epigenetic gene downregulation suggestive of a metabolic shift of cellular respiration from oxidative phosphorylation to glycolysis and aberrant cell cycle regulation facilitating cell proliferation from as early as 28days after hepatocarcinogen treatment contribute to tumor development.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Epigênese Genética/efeitos dos fármacos , Neoplasias Hepáticas/induzido quimicamente , Fígado/efeitos dos fármacos , Proteínas de Membrana/genética , Tioacetamida/toxicidade , Ubiquitina-Proteína Ligases/genética , Adenoma de Células Hepáticas/induzido quimicamente , Animais , Carcinoma Hepatocelular/induzido quimicamente , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fígado/patologia , Ratos
14.
Exp Toxicol Pathol ; 68(7): 399-408, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27402199

RESUMO

The present study aimed to determine the onset time of hepatocarcinogen/hepatocarcinogenic tumor promoter-specific cell proliferation, apoptosis and aberrant cell cycle regulation after post-initiation treatment. Six-week-old rats were treated with the genotoxic hepatocarcinogen, carbadox (CRB), the marginally hepatocarcinogenic leucomalachite green (LMG), the tumor promoter, ß-naphthoflavone (BNF) or the non-carcinogenic hepatotoxicant, acetaminophen, for 2, 4 or 6 weeks during the post-initiation phase using a medium-term liver bioassay. Cell proliferation activity, expression of G2 to M phase- and spindle checkpoint-related molecules, and apoptosis were immunohistochemically analyzed at week 2 and 4, and tumor promotion activity was assessed at week 6. At week 2, hepatocarcinogen/tumor promoter-specific aberrant cell cycle regulation was not observed. At week 4, BNF and LMG increased cell proliferation together with hepatotoxicity, while CRB did not. Additionally, BNF and CRB reduced the number of cells expressing phosphorylated-histone H3 in both ubiquitin D (UBD)(+) cells and Ki-67(+) proliferating cells, suggesting development of spindle checkpoint dysfunction, regardless of cell proliferation activity. At week 6, examined hepatocarcinogens/tumor promoters increased preneoplastic hepatic foci expressing glutathione S-transferase placental form. These results suggest that some hepatocarcinogens/tumor promoters increase their toxicity after post-initiation treatment, causing regenerative cell proliferation. In contrast, some genotoxic hepatocarcinogens may disrupt the spindle checkpoint without facilitating cell proliferation at the early stage of tumor promotion. This suggests that facilitation of cell proliferation and disruption of spindle checkpoint function are induced by different mechanisms during hepatocarcinogenesis. Four weeks of post-initiation treatment may be sufficient to induce hepatocarcinogen/tumor promoter-specific cellular responses.


Assuntos
Apoptose/efeitos dos fármacos , Carcinógenos/toxicidade , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Fígado/efeitos dos fármacos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Acetaminofen/toxicidade , Animais , Carbadox/toxicidade , Cocarcinogênese , Dietilnitrosamina/toxicidade , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos Endogâmicos F344 , Corantes de Rosanilina/toxicidade , Fatores de Tempo , beta-Naftoflavona/toxicidade
15.
J Toxicol Sci ; 41(1): 91-104, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26763396

RESUMO

We previously reported that 28-day exposure to hepatocarcinogens that facilitate cell proliferation specifically alters the expression of G1/S checkpoint-related genes and proteins, induces aberrant early expression of ubiquitin D (UBD) at the G2 phase, and increases apoptosis in the rat liver, indicating G1/S and spindle checkpoint dysfunction. The present study aimed to determine the time of onset of carcinogen-specific cell-cycle disruption after repeated administration of renal carcinogens for up to 28 days. Rats were orally administered the renal carcinogens nitrofurantoin (NFT), 1-amino-2,4-dibromoantraquinone (ADAQ), and 1,2,3-trichloropropane (TCP) or the non-carcinogenic renal toxicants 1-chloro-2-propanol, triamterene, and carboxin for 3, 7 or 28 days. Both immunohistochemical single-molecule analysis and real-time RT-PCR analysis revealed that carcinogen-specific expression changes were not observed after 28 days of administration. However, the renal carcinogens ADAQ and TCP specifically reduced the number of cells expressing phosphorylated-histone H3 at Ser10 in both UBD(+) cells and proliferating cells, suggestive of insufficient UBD expression at the M phase and early transition of proliferating cells from the M phase, without increasing apoptosis, after 28 days of administration. In contrast, NFT, which has marginal carcinogenic potential, did not induce such cellular responses. These results suggest that it may take 28 days to induce spindle checkpoint dysfunction by renal carcinogens; however, induction of apoptosis may not be essential. Thus, induction of spindle checkpoint dysfunction may be dependent on carcinogenic potential of carcinogen examined, and marginal carcinogens may not exert sufficient responses even after 28 days of administration.


Assuntos
Antraquinonas/administração & dosagem , Antraquinonas/toxicidade , Rim/citologia , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Nitrofurantoína/administração & dosagem , Nitrofurantoína/toxicidade , Propano/análogos & derivados , Animais , Peso Corporal/efeitos dos fármacos , Carboxina/administração & dosagem , Carboxina/toxicidade , Proliferação de Células/efeitos dos fármacos , Cloridrinas/administração & dosagem , Cloridrinas/toxicidade , Histonas/metabolismo , Rim/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Propano/administração & dosagem , Propano/toxicidade , Ratos Endogâmicos F344 , Fatores de Tempo , Triantereno/administração & dosagem , Triantereno/toxicidade , Ubiquitinas/metabolismo
16.
J Toxicol Sci ; 40(6): 855-71, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26558467

RESUMO

We aimed to clarify the hepatocarcinogen-specific disruption of cell cycle checkpoint functions and its time course after repeated administration of hepatocarcinogens. Thus, rats were repeatedly administered with hepatocarcinogens (methapyrilene, carbadox and thioacetamide), a marginal hepatocarcinogen (leucomalachite green), hepatocarcinogenic promoters (oxfendazole and ß-naphthoflavone) or non-carcinogenic hepatotoxicants (promethazine and acetaminophen) for 7, 28 or 90 days, and the temporal changes in cell proliferation, expression of G1/S and spindle checkpoint-related molecules, and apoptosis were examined using immunohistochemistry and/or real-time RT-PCR analysis. Hepatocarcinogens facilitating cell proliferation at day 28 of administration also facilitated cell proliferation and apoptosis at day 90. Hepatocarcinogen- or hepatocarcinogenic promoter-specific cellular responses were not detected by immunohistochemical single molecule analysis even after 90 days. Expression of Cdkn1a, Mad2l1, Chek1 and Rbl2 mRNA also lacked specificity to hepatocarcinogens or hepatocarcinogenic promoters. In contrast, all hepatocarcinogens and the marginally hepatocarcinogenic leucomalachite green induced Mdm2 upregulation or increase in the number of phosphorylated MDM2(+) cells from day 28, irrespective of the lack of cell proliferation facilitation by some compounds. However, different Tp53 expression levels suggest different mechanisms of induction or activation of MDM2 among hepatocarcinogens. On the other hand, hepatocarcinogenic methapyrilene and carbadox downregulated the number of both ubiquitin D(+) cells and proliferating cells remaining in M phase at day 28 and/or day 90, irrespective of the lack of cell proliferation facilitation in the latter. These results suggest that hepatocarcinogens disrupt spindle checkpoint function after 28 or 90 days of administration, which may be induced ahead of cell proliferation facilitation.


Assuntos
Carbadox/toxicidade , Carcinógenos/administração & dosagem , Carcinógenos/toxicidade , Proliferação de Células/efeitos dos fármacos , Fígado/citologia , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Metapirileno/toxicidade , Tioacetamida/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzimidazóis/administração & dosagem , Benzimidazóis/toxicidade , Carbadox/administração & dosagem , Proliferação de Células/genética , Quinase 1 do Ponto de Checagem , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Expressão Gênica/efeitos dos fármacos , Masculino , Metapirileno/administração & dosagem , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ratos Endogâmicos F344 , Corantes de Rosanilina/toxicidade , Fatores de Tempo , Ubiquitinas/genética , Ubiquitinas/metabolismo
17.
Chem Biodivers ; 2(8): 1063-78, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17193190

RESUMO

Lactoside primers (dodecyl lactoside derivatives) resemble intermediates in the biosynthetic pathway of glycolipids and, therefore, act as substrates for cellular enzyme-catalyzed glycosylation. To establish the optimal condition for the bioproduction of a large amount of valuable materials containing GM3-type oligosaccharides, two kinds of lactoside primers having the azido group in different positions were synthesized and introduced into B16 melanoma cells. The saccharide chains of both primers were elongated by cells to give GM3-type oligosaccharide derivatives, which were released to the culture medium. The amount of glycosylated product from newly synthesized 2-azidododecyl beta-lactoside (primer II) was almost twice that from 12-azidododecyl beta-lactoside (primer I). The effects of seeded cell number, primer concentration, and length of incubation time on the glycosylation efficiency were also investigated. The results showed that the higher the seeded cell number, the larger the amount of sialylated products obtained. The optimum concentrations of primers I and II were found to be 200 and 100 microM, respectively. Above these concentrations, productivity and cell viability decreased. As regards the length of incubation time, the sialylated products increased linearly until 48 h, but productivity did not advance thereafter. These results represent the optimal conditions that are necessary for the mass production of GM3-type oligosaccharide using azidododecyl lactoside primers and B16 cells.


Assuntos
Glicoesfingolipídeos/química , Glicoesfingolipídeos/metabolismo , Melanoma Experimental/metabolismo , Animais , Linhagem Celular Tumoral , Camundongos
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