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1.
Br J Surg ; 106(5): 616-625, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30725479

RESUMO

BACKGROUND: Visceral obesity is one of the risk factors for clinically relevant pancreatic fistula after pancreatic resection. The objective of this study was to evaluate the impact of intraperitoneal lipolysis on postoperative pancreatic fistula. METHODS: The degree of intraperitoneal lipolysis was investigated by measuring the free fatty acid concentration in drain discharge in patients after pancreatic resection. An experimental pancreatic fistula model was prepared by pancreatic transection, and the impact of intraperitoneal lipolysis was evaluated by intraperitoneal administration of triolein (triglyceride) with, or without orlistat (lipase inhibitor). RESULTS: Thirty-three patients were included in the analysis. The free fatty acid concentration in drain discharge on postoperative day 1 was significantly associated with the development of a clinically relevant pancreatic fistula (P = 0·004). A higher free fatty acid concentration in drain discharge was associated with more visceral adipose tissue (P = 0·009). In the experimental model that included 98 rats, intraperitoneal lipolysis caused an increased amount of pancreatic juice leakage and multiple organ dysfunction. Intraperitoneal administration of a lipase inhibitor reduced lipolysis and prevented deterioration of the fistula. CONCLUSION: Intraperitoneal lipolysis significantly exacerbates pancreatic fistula after pancreatic resection. Inhibition of lipolysis by intraperitoneal administration of a lipase inhibitor could be a promising therapy to reduce clinically relevant postoperative pancreatic fistula. Surgical relevance Clinically, there are two types of pancreatic fistula after pancreatic resections: harmless biochemical leak and harmful clinically relevant pancreatic fistula. Visceral obesity is one of the known risk factors for clinically relevant pancreatic fistula; however, the underlying mechanisms remained to be elucidated. Patients with clinically relevant pancreatic fistula had a higher free fatty acid concentration in the drain discharge, suggesting a relationship between intraperitoneal lipolysis and pancreatic fistula. The experimental model of pancreatic fistula demonstrated that intraperitoneal lipolysis caused deterioration in pancreatic fistula, suggesting that intraperitoneal lipolysis is one of the mechanisms that drives biochemical leakage to clinically relevant pancreatic fistula. Intraperitoneal administration of a lipase inhibitor prevented lipolysis as well as pancreatic fistula deterioration in the experimental model, suggesting a future clinical application for lipase inhibitors in prevention of clinically relevant pancreatic fistula.


Assuntos
Gordura Intra-Abdominal/fisiopatologia , Lipólise/fisiologia , Pancreatectomia/efeitos adversos , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Idoso , Animais , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/análise , Feminino , Humanos , Lipase/antagonistas & inibidores , Lipólise/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/complicações , Obesidade Abdominal/fisiopatologia , Fístula Pancreática/prevenção & controle , Suco Pancreático/fisiologia , Complicações Pós-Operatórias/fisiopatologia , Ratos Sprague-Dawley , Fatores de Risco
2.
Nature ; 442(7102): 546-50, 2006 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-16885980

RESUMO

Formation of electron pairs is essential to superconductivity. For conventional superconductors, tunnelling spectroscopy has established that pairing is mediated by bosonic modes (phonons); a peak in the second derivative of tunnel current d2I/dV2 corresponds to each phonon mode. For high-transition-temperature (high-T(c)) superconductivity, however, no boson mediating electron pairing has been identified. One explanation could be that electron pair formation and related electron-boson interactions are heterogeneous at the atomic scale and therefore challenging to characterize. However, with the latest advances in d2I/dV2 spectroscopy using scanning tunnelling microscopy, it has become possible to study bosonic modes directly at the atomic scale. Here we report d2I/dV2 imaging studies of the high-T(c) superconductor Bi2Sr2CaCu2O8+delta. We find intense disorder of electron-boson interaction energies at the nanometre scale, along with the expected modulations in d2I/dV2 (refs 9, 10). Changing the density of holes has minimal effects on both the average mode energies and the modulations, indicating that the bosonic modes are unrelated to electronic or magnetic structure. Instead, the modes appear to be local lattice vibrations, as substitution of 18O for 16O throughout the material reduces the average mode energy by approximately 6 per cent--the expected effect of this isotope substitution on lattice vibration frequencies. Significantly, the mode energies are always spatially anticorrelated with the superconducting pairing-gap energies, suggesting an interplay between these lattice vibration modes and the superconductivity.

3.
Calcif Tissue Int ; 89(2): 111-22, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21597909

RESUMO

The full range of fracture risk determinants arise from each hierarchical level comprising the organization of bone. Raman spectroscopy is one tool capable of characterizing the collagen and mineral phases at a near submicron-length scale, but the ability of Raman spectra to distinguish compositional differences of bone is not well defined. Therefore, we analyzed multiple Raman peak intensities and peak ratios to characterize their ability to distinguish between the typically less mineralized osteonal tissue and the more mineralized interstitial tissue in intracortical human bone. To further assess origins of variance, we collected Raman spectra from embedded specimens and for two orientations of cut. Per specimen, Raman peak intensities or ratios were averaged among multiple sites within five osteons and five neighboring interstitial tissue. The peak ratios of ν(1) phosphate (PO(4)) to proline or amide III detected the highest increases of 15.4 or 12.5%, respectively, in composition from osteonal to interstitial tissue. The coefficient of variance was less than 5% for each as opposed to a value of ~8% for the traditional ν(1)PO(4)/amide I, a peak ratio that varied the most between transverse and longitudinal cuts for each tissue type. Although embedding affected Raman peaks, it did not obscure differences in most peak ratios related to mineralization between the two tissue types. In studies with limited sample size but sufficient number of Raman spectra per specimen for spatial averaging, ν(1)PO(4)/amide III or ν(1)PO(4)/proline is the Raman property that is most likely to detect a compositional difference between experimental groups.


Assuntos
Densidade Óssea , Osso e Ossos/química , Análise Espectral Raman/métodos , Idoso de 80 Anos ou mais , Animais , Densidade Óssea/fisiologia , Osso e Ossos/ultraestrutura , Feminino , Humanos , Individualidade , Masculino , Camundongos , Microdissecção/métodos , Pessoa de Meia-Idade , Especificidade de Órgãos/fisiologia , Ratos , Inclusão do Tecido/métodos , Preservação de Tecido/métodos , Pesos e Medidas
4.
Jpn J Clin Oncol ; 41(6): 803-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21478179

RESUMO

The safety of chemotherapy for patients with systemic sclerosis is unclear, and there are few published reports documenting the side effects of chemotherapy in patients with this condition. Here, we report the case of a patient with systemic sclerosis who developed severe digital ischemia during combination gemcitabine/S-1 chemotherapy for pancreatic cancer. In spite of aggressive treatment, the digital ischemia progressively worsened and gangrenous changes developed in multiple fingers and toes. In this patient, the systemic sclerosis had been well controlled, with no digital ischemic symptoms for the previous 6 years, so this progressive clinical course in spite of aggressive treatment strongly suggests that the chemotherapy triggered or aggravated the digital necrosis. To the best of our knowledge, this is only the third reported case of a patient with systemic sclerosis developing digital necrosis after gemcitabine-based chemotherapy. The incidence of digital necrosis during chemotherapy in patients with systemic sclerosis is unknown, and the mechanism by which it occurs is unclear, but the three reports published to date, including the present case, suggest that physicians should be very cautious about administering gemcitabine-based chemotherapy to patients with systemic sclerosis. Any resulting digital ischemia might be refractory to treatment and worsen progressively, even if chemotherapy is withdrawn in the early stages of digital ischemia.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Desoxicitidina/análogos & derivados , Dedos/patologia , Isquemia/induzido quimicamente , Ácido Oxônico/efeitos adversos , Escleroderma Sistêmico/complicações , Tegafur/efeitos adversos , Dedos do Pé/patologia , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Progressão da Doença , Esquema de Medicação , Combinação de Medicamentos , Evolução Fatal , Gangrena/induzido quimicamente , Humanos , Isquemia/tratamento farmacológico , Isquemia/etiologia , Isquemia/terapia , Masculino , Necrose/induzido quimicamente , Ácido Oxônico/administração & dosagem , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Doença de Raynaud/induzido quimicamente , Tegafur/administração & dosagem , Gencitabina
5.
J Cell Biol ; 105(2): 965-75, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2887577

RESUMO

Scatchard analyses of the binding of transforming growth factor-beta (TGF-beta) to a wide variety of different cell types in culture revealed the universal presence of high affinity (Kd = 1-60 pM) receptors for TGF-beta on every cell type assayed, indicating a wide potential target range for TGF-beta action. There was a strong (r = +0.85) inverse relationship between the receptor affinity and the number of receptors expressed per cell, such that at low TGF-beta concentrations, essentially all cells bound a similar number of TGF-beta molecules per cell. The binding of TGF-beta to various cell types was not altered by many agents that affect the cellular response to TGF-beta, suggesting that modulation of TGF-beta binding to its receptor may not be a primary control mechanism in TGF-beta action. Similarly, in vitro transformation resulted in only relatively small changes in the cellular binding of TGF-beta, and for those cell types that exhibited ligand-induced down-regulation of the receptor, down-regulation was not extensive. Thus the strong conservation of binding observed between cell types is also seen within a given cell type under a variety of conditions, and receptor expression appears to be essentially constitutive. Finally, the biologically inactive form of TGF-beta, which constitutes greater than 98% of autocrine TGF-beta secreted by all of the twelve different cell types assayed, was shown to be unable to bind to the receptor without prior activation in vitro. It is proposed that this may prevent premature interaction of autocrine ligand and receptor in the Golgi apparatus.


Assuntos
Substâncias de Crescimento/metabolismo , Peptídeos/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Anticorpos , Células Cultivadas , Meios de Cultura , Humanos , Cinética , Receptores de Fatores de Crescimento Transformadores beta , Fatores de Crescimento Transformadores
6.
Eur Phys J E Soft Matter ; 27(4): 379-89, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19089480

RESUMO

Using a contrast matching technique of small angle neutron scattering (SANS), we have investigated a phase separation to liquid-disordered and liquid-ordered phases on ternary small unilamellar vesicles (SUVs) composed of deuterated-saturated, hydrogenated-unsaturated phosphatidylcholine lipids and cholesterol, where the equilibrium size of these domains is constrained to less than 10nm by the system size. Below a miscibility temperature, we observed characteristic scattering profiles with a maximum, indicating the formation of nano-meter-sized domains on the SUVs. The observed profiles can be described by a multi-domain model rather than a mono-domain model. The nano-meter-sized domain is agitated by thermal fluctuations and eventually ruptured, which may result in the multi-domain state. The kinetically trapped nano-meter-sized domains grow to a mono-domain state by decreasing temperature. Furthermore, between the miscibility and disorder-order transition temperature of saturated lipid, the integrated SANS intensity increased slightly, indicating the formation of nano-meter-sized heterogeneity prior to the domain nucleation.


Assuntos
Lipídeos de Membrana/química , Microdomínios da Membrana/química , Nanotecnologia , Difração de Nêutrons , Espalhamento a Baixo Ângulo , Lipossomas Unilamelares/química
7.
Int J Tuberc Lung Dis ; 11(8): 928-30, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17705962

RESUMO

The study aims to determine whether the tuberculosis (TB) patients referred from the National Tuberculosis Institute (NTI), Sana'a City, actually present themselves, are registered and initiate treatment at the health facilities to which they are referred. In 2004, 591 smear-positive TB cases were diagnosed, 481 cases were referred back to health centres, 75 cases were registered at the NTI and 35 cases could not be retrieved. Among the 481 referred cases, 427 cases actually presented themselves and were registered at the health centres (88.8%). The average number of days between the day of referral and that of registration was 2.5 days (median 1 day).


Assuntos
Inquéritos e Questionários , Tuberculose , Instalações de Saúde , Humanos , Encaminhamento e Consulta , Tuberculose/diagnóstico , Iêmen
8.
Int J Tuberc Lung Dis ; 11(12): 1328-33, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18034954

RESUMO

OBJECTIVES: To determine the prevalence of resistance to the four major anti-tuberculosis drugs, isoniazid, rifampicin, streptomycin and ethambutol, in Yemen. METHODS: Cluster sampling with probability proportionate to size was applied. Susceptibility to four major anti-tuberculosis drugs was examined. The proportion method using Löwenstein-Jensen medium or Ogawa medium was carried out. RESULTS: A total of 790 primary culture isolates from tuberculosis (TB) cases enrolled at the National Tuberculosis Institute, Yemen, were examined. In the confirmation culture at the supranational reference laboratory, 227 of them failed to grow on the secondary culture or were proved to be mycobacteria other than Mycobacterium tuberculosis and were excluded from further analysis. Among 563 cultures, 510 were obtained from new cases and 53 from previously treated cases. The prevalence of resistance to any four drugs was 9.8% (95%CI 7.0-12.5) among new cases and 17.4% (95%CI 12.0-33.5) among previously treated cases. The prevalence of multidrug-resistant TB was 3.0% (95%CI 1.5-4.5) among new cases and 9.4% (95%CI 0.2-18.7) among previously treated cases. CONCLUSION: The first nationwide prevalence survey on resistance to the four major anti-tuberculosis drugs in Yemen showed a relatively low prevalence of drug-resistant cases, but a high prevalence of multidrug resistance among new cases.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Adulto , Distribuição de Qui-Quadrado , Etambutol/uso terapêutico , Feminino , Humanos , Isoniazida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Prevalência , Rifampina/uso terapêutico , Estreptomicina/uso terapêutico , Iêmen/epidemiologia
9.
J Natl Cancer Inst ; 78(2): 289-93, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3468292

RESUMO

The effects of butylated hydroxyanisole [(BHA) CAS: 25013-16-5], alpha-tocopherol [(TC) CAS: 59-02-9], and carbazole [(CA) CAS: 86-74-8] administered subsequent to a single dose of 2,2'-dioxo-N-nitrosodipropylamine [(DOPN) CAS: 60599-38-4] on the development of putative preneoplastic lesions were investigated in Syrian golden hamsters. Whereas the 2 antioxidants BHA and TC inhibited the incidence of both liver and pancreatic lesions, CA, itself giving rise to considerable numbers of enzyme-altered foci, enhanced carcinogenesis in the liver while inhibiting carcinogenesis in the pancreas. All 3 of these agents induced hyperplastic and papillomatous lesions in the forestomachs of treated animals, independent of prior DOPN treatment; these forestomach lesions were not evident in controls. Cellular atypia and invasive growth characteristics signifying malignant change were also observed in BHA-induced forestomach lesions. The results demonstrate that hepatocarcinogenesis in the Syrian golden hamster, like that in the rat, can be inhibited by antioxidants. The similar decrease in putative preneoplastic lesion yield evident in the pancreas of BHA- or TC-treated hamsters, considered in the light of similarities in altered enzyme phenotype in carcinogen-induced lesions of both organs, suggests that common biochemical changes can be an underlying factor in the modification of neoplastic development in liver and pancreas. The present results also provide further evidence that CA has carcinogenic potential for the liver and forestomach of experimental animals.


Assuntos
Hidroxianisol Butilado/farmacologia , Carbazóis/farmacologia , Carcinógenos , Nitrosaminas , Lesões Pré-Cancerosas/induzido quimicamente , Vitamina E/farmacologia , Animais , Cricetinae , Neoplasias Hepáticas/induzido quimicamente , Mesocricetus , Neoplasias Pancreáticas/induzido quimicamente
10.
Cancer Res ; 47(19): 5171-4, 1987 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-3621202

RESUMO

The reversibility of forestomach lesions induced in rats by butylated hydroxyanisole (BHA) was examined. F344 rats were given a 2% BHA diet for 24, 48, or 72 wk followed by a basal diet for the remainder of the 96-wk experiment. Two other groups of rats were given a 2% BHA diet or basal diet alone for 96 wk. The forestomach lesions at wk 24, 48, 72, or 96 were compared histopathologically. The results showed that exophytic epithelial proliferation (simple hyperplasia or papilloma) induced by BHA was reversible, while endophytic proliferation of basal cells (basal cell hyperplasia) persisted after withdrawal of BHA administration. This suggests that simple hyperplasia and papilloma of the forestomach induced by BHA are not autonomous and need continuous feeding of BHA to develop further.


Assuntos
Hidroxianisol Butilado/toxicidade , Papiloma/induzido quimicamente , Neoplasias Gástricas/induzido quimicamente , Estômago/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Hiperplasia , Masculino , Papiloma/patologia , Ratos , Ratos Endogâmicos F344 , Estômago/patologia , Neoplasias Gástricas/patologia
11.
Cancer Res ; 46(4 Pt 2): 2062-7, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3948181

RESUMO

Male F344 rats were given a diet supplemented with uracil at concentrations of 1 or 3% for 15 or 30 wk. In the group given 3% uracil, numerous calculi of uracil were observed in the urinary tract with marked hyperplasia and papillomas of the urinary bladder mucosa in Wk 15 and 30. In Wk 30, dysplasia of the ureteral mucosa and one transitional cell carcinoma of the bladder were also found. Neither these marked proliferative lesions nor calculi except for one papilloma were observed in rats maintained on normal basal diet for 15 wk after a diet containing 3% uracil for 15 wk. In the group given 1% uracil, no calculi or hyperplasia was seen in Wk 15 (five rats), and only one of ten rats examined in Wk 30 had a few stones and mild epithelial hyperplasia of the bladder. Scanning electron microscopy showed that most surface cells of papillomas had numerous short uniform microvilli and ropy rounded microridges. By transmission electron microscopy, epithelial cells of papillomas showed essentially normal differentiation. The present findings suggested that most hyperplasias and papillomas induced by bladder stones were reversible.


Assuntos
Papiloma/induzido quimicamente , Uracila/toxicidade , Cálculos da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Hiperplasia , Masculino , Microscopia Eletrônica , Papiloma/patologia , Papiloma/ultraestrutura , Ratos , Ratos Endogâmicos F344 , Bexiga Urinária/patologia , Bexiga Urinária/ultraestrutura , Cálculos da Bexiga Urinária/metabolismo , Cálculos da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/ultraestrutura
12.
Cancer Res ; 49(14): 3789-94, 1989 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-2736520

RESUMO

Rats were fed sodium saccharin as 5 or 7.5% of the diet by weight, and proliferation of the bladder epithelium was assessed by autoradiography, histology, and scanning electron microscopy. In Experiment 1, male F344 rats, 5 weeks old, were placed on a diet of 0, 5, or 7.5% NaS mixed in Prolab 3200, NIH-07, or AIN-76A diet for 4 or 10 weeks. In Experiment 2, 5-week-old F344 rats or 4-week-old Sprague-Dawley rats were fed 0, 5, or 7.5% NaS in Prolab 3200 or Purina 5002 diet for 10 weeks. In Experiment 1, at both the 4- and 10-week intervals, NaS had a greater effect on the urothelium when administered in the Prolab diet compared to the NIH diet, and there was little response with the AIN diet. Eight of 10 rats fed 7.5% NaS in Prolab 3200 for 4 or 10 weeks had bladders with simple or nodular hyperplasia, and eight of nine bladders contained abnormal surface features visible by scanning electron microscopy. At 10 weeks for control animals, the average labeling index following [3H]thymidine incorporation into bladder epithelium was approximately 0.05%. For rats fed 7.5% NaS diets, the labeling index was 0.43% for Prolab, 0.14% for NIH-07, and 0.04% for AIN-76A. In Experiment 2, the response to NaS was considerably greater in F344 rats than in Sprague-Dawley rats fed the same diet, and for both strains, the response to NaS was greater in Prolab than in Purina diets. In conclusion, the proliferative effect of NaS on male rat urinary bladder depended on rat strain as well as on type of diet.


Assuntos
Dieta , Sacarina/toxicidade , Bexiga Urinária/patologia , Animais , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos , Especificidade da Espécie , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/ultraestrutura
13.
Cancer Res ; 55(2): 399-407, 1995 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-7529136

RESUMO

A hormone-dependent, clonal carcinoma cell line, designated RM22-F5, was derived from a malignant mammary mixed tumor spontaneously arising in an outbred old female Wistar rat. These cells expressed keratin and desmosomal protein and formed epithelial monolayers in a growth factor and hormone-supplemented medium (LHC-8) containing 10% fetal bovine serum (E-type cells). Cells subcultured for 6 to 8 passages in RPMI 1640 medium containing 10% fetal bovine serum without supplements appeared to be fibroblastic and expressed vimentin (F-type cells). The shift to a fibroblast-like morphology was associated with a more malignant phenotype which included rapid, hormone-independent growth and invasive sarcoma-like character in nude mice. F-type cells were no longer able to express their original epithelial phenotype in LHC-8 medium. Cytogenetic analysis revealed that both E- and F-type cells had essentially the same karyotype. Analysis of PCR-amplified DNA further demonstrated a point mutation of the H-ras-1 gene at codon 12 and loss of the normal H-ras-1 allele in both cell types. Genetic tagging of E-type cells with the neomycin-resistance gene resulted in the generation of F-type cells with neomycin resistance in RPMI 1640 medium, suggesting that F-type cells are a malignant variant of E-type cells arising during in vitro culture. Somatic cell fusion between E- and F-type cells revealed that with most hybrid clones tested, the fibroblast-like phenotype was greatly suppressed. These results suggest that an irreversible phenotypic transition, representative of tumor progression from hormone-dependent adenocarcinoma to more malignant hormone-independent spindle carcinoma cells, is a recessive event and may involve loss of a suppressor function.


Assuntos
Adenocarcinoma/patologia , Carcinoma/patologia , Transformação Celular Neoplásica/patologia , Neoplasias Mamárias Animais/patologia , Neoplasias Hormônio-Dependentes/patologia , Adenocarcinoma/química , Adenocarcinoma/genética , Animais , Sequência de Bases , Carcinoma/química , Carcinoma/genética , Divisão Celular , Fusão Celular , Transformação Celular Neoplásica/química , Transformação Celular Neoplásica/genética , Meios de Cultura , Desmossomos/química , Feminino , Citometria de Fluxo , Genes ras/genética , Queratinas/análise , Neoplasias Mamárias Animais/química , Neoplasias Mamárias Animais/genética , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Neomicina , Invasividade Neoplásica , Neoplasias Hormônio-Dependentes/química , Neoplasias Hormônio-Dependentes/genética , Fenótipo , Ratos , Ratos Wistar , Transfecção , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/patologia , Vimentina/análise
14.
Cancer Res ; 51(7): 1778-82, 1991 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2004361

RESUMO

Sodium saccharin (NaSac) fed as 5% of Prolab diet promotes bladder tumor carcinogenesis in male F344 rats initiated with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) fed as 0.2% of the diet for 4 weeks. NaSac also increases urothelial proliferation if fed for short periods in Prolab diet, but no increased proliferation is seen if it is fed for up to 10 weeks in AIN-76A semisynthetic diet, even at levels as high as 7.5% of the diet. To determine whether NaSac as part of an AIN-76A diet has promoting activity, groups of approximately 30 male, 5-week-old F344 rats were fed AIN-76A diet containing (a) 0.2% FANFT for 4 weeks followed by 5% NaSac for 100 weeks; (b) 0.2% FANFT followed by control diet; or (c) control diet followed by 5% NaSac. Bladder tumor incidences were 10, 23, and 0%, respectively. When fed in Prolab diet, 0.2% FANFT for 4 weeks followed by NaSac or control diet for 100 weeks resulted in bladder tumor incidences of 40 and 17%, respectively. Groups of rats fed 0.1 or 0.2% FANFT for 1 or 2 weeks followed by 5% NaSac or control diet for 100 weeks had bladder tumor incidences of 0 to 7%. These data demonstrate that NaSac does not promote bladder cancer in male rats if fed in AIN-76A diet. Other studies suggest that this is due to the low urinary pH in rats fed AIN-76A diet.


Assuntos
Sacarina/toxicidade , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Carcinoma/induzido quimicamente , Ingestão de Líquidos/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , FANFT , Hiperplasia/induzido quimicamente , Masculino , Papiloma/induzido quimicamente , Ratos , Ratos Endogâmicos F344 , Sódio/efeitos adversos , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia
15.
Cancer Res ; 47(2): 573-8, 1987 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-3791242

RESUMO

The human lung tumor-derived cell lines A549, Calu-1, Calu-3, HuT292, and SW900 and the transformed human bronchial epithelial cell line TBE-1, that was transfected with the v-Harvey-ras oncogene, were inoculated into deepithelialized Fisher 344 rat tracheas (5 X 10(5) cells/trachea). After the ends of the tracheas were sealed, the tracheas were transplanted into s.c. tissues of nude mice. In a parallel experiment, 1 X 10(6) cells from each of these cell lines were injected s.c. Histological examination of the tracheal transplants 2, 4, 8, 12, and 16 weeks after cell inoculation proved to be of greater usefulness than either clinical or histological observation of the s.c. injection sites. A549, Calu-1, and TBE-1 produced intratracheal neoplastic nodules as early as 2 weeks after cell inoculation. Calu-3, HuT292, and SW900 grew relatively slowly in the tracheas, and simple or stratified epithelia with slight or moderate atypia (preneoplastic lesions) were seen at 2 weeks. After the 4th week, they produced tumor nodules in the tracheal transplants, whereas no tumor cells could be seen at the s.c. injection sites. The human derivation of the cells was confirmed by in situ hybridization using human-specific DNA probes. The intratracheal inoculation and xenotransplantation of human-derived cell lines offers a time-saving alternative to the s.c. inoculation assay for tumorigenicity and is at the same time a potentially valuable approach to studying preneoplastic and neoplastic progression with human cell subpopulations.


Assuntos
Neoplasias Pulmonares/patologia , Neoplasias Experimentais/patologia , Lesões Pré-Cancerosas/patologia , Animais , Linhagem Celular , Epitélio/patologia , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Ratos , Traqueia/patologia
16.
Cancer Res ; 51(7): 1766-77, 1991 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2004360

RESUMO

Sodium saccharin and sodium ascorbate are known to promote urinary bladder carcinogenesis in rats following initiation with N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) or N-butyl-N-(4-hydroxybutyl) nitrosamine. Sodium salts of other organic acids have also been shown to be bladder tumor promoters. In addition, these substances increase urothelial proliferation in short term assays in rats when fed at high doses. When they have been tested, the acid forms of these salts are without either promoting or cell proliferative inducing activity. The following experiment was designed to compare the tumor promoting activity of various forms of saccharin and to evaluate the role in promotion of urinary sodium, calcium, and pH as well as other factors. Twenty groups of 40 male F344 rats, 5 weeks of age, were fed either FANFT or control diet during a 6-week initiation phase followed by feeding of a test compound for 72 weeks in the second phase. The chemicals were administered to the first 18 groups in Agway Prolab 3200 diet and the last 2 groups were fed NIH-07 diet. The treatments were as follows: (a) FANFT----5% sodium saccharin (NaS); (b) FANFT----3% NaS; (c) FANFT----5.2% calcium saccharin (CaS); (d) FANFT----3.12% CaS; (e) FANFT----4.21% acid saccharin (S); (f) FANFT----2.53% S; (g) FANFT----5% sodium ascorbate; (h) FANFT----4.44% ascorbic acid; (i) FANFT----5% NaS plus 1.15% CaCO3; (j) FANFT----5.2% CaS plus 1.34% NaCl; (k) FANFT----5% NaS plus 1.23% NH4Cl; (l) FANFT----1.15% CaCO3; (m) FANFT----1.34% NaCl; (n) FANFT----control; (o) control----5% NaS; (p) control----5.2% CaS; (q) control----4.21% S; (r) Control----control; (s) FANFT----5% NaS (NIH-07 diet); (t) FANFT----control (NIH-07 diet). NaS, CaS and S without prior FANFT administration were without tumorigenic activity. NaS was found to have tumor promoting activity, showing a positive response at the 5 and 3% dose levels, with significantly greater activity at the higher dose. CaS had slight tumor promoting activity but without a dose response, and S showed no tumor promoting activity. In addition, NaCl showed weak tumor promoting activity, but CaCO3 was without activity. NH4Cl completely inhibited the tumor promoting activity of NaS when concurrently administered with it. NaCl administered with CaS or CaCO3 administered with NaS showed activity similar to that of NaS. Sodium ascorbate was also shown to have tumor promoting activity, with slightly less activity than NaS. Ascorbic acid showed no tumor promoting activity.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Ácido Ascórbico/toxicidade , Sacarina/toxicidade , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Butilidroxibutilnitrosamina , Carbonato de Cálcio/toxicidade , Dieta , Ingestão de Líquidos/efeitos dos fármacos , Sinergismo Farmacológico , FANFT , Concentração de Íons de Hidrogênio , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos F344 , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Urina
17.
Cancer Res ; 51(13): 3471-5, 1991 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2054786

RESUMO

Male F344 rats were fed 0.2% N-[4-(5-nitro-2-furyl)-2-thiazoly]formamide for 6 weeks and then fed 3% or 5% sodium saccharin, 5% sodium ascorbate, 3.12% calcium saccharin, 1.34% sodium chloride, 5.2% calcium saccharin plus 1.34% sodium chloride, or basal diet alone for 72 weeks. Protein and DNA were extracted from 89 bladder tumors [87 transitional cell carcinomas (TCC), 1 papilloma, and 1 sarcoma] from 86 rats p21 expression was examined by Western blotting using a monoclonal antibody against p21 (NCC-RAS-004). H-ras mutations in exons 1 and 2 were examined by direct sequencing of DNA amplified by polymerase chain reaction. Sequencing results demonstrated mutations at codon 61 (CAA to CGA in 15 TCCs; CAA to CTA in 2 TCCs), at codon 12 (GGA to TGG in 1 TCC), and at codon 13 (GGC to GTC in 3 TCCs). Mutations at codon 61 were confirmed by faster mobility of the p21 band in Western blots. The level of p21 expression varied among samples, but many TCCs appeared to express more p21 than controls. The overall incidence of H-ras mutations was 24.4% (21 of 86 rats). The type of chemical used for the promoting phase had essentially no effect on H-ras mutation, suggesting that the effects observed were related to FANFT administration. The frequency of H-ras mutation in each group was negatively related to the incidence of carcinoma (r = -0.85; P less than 0.01). Two groups of tumors (with or without the mutated ras gene) were compared for tumor size (reflected by the bladder weight), histological grading, and the presence of invasion. The size of tumors with mutated ras was significantly smaller than those without mutated ras. There was no difference in the histological grading between the two groups. Although not statistically significant, histological invasion was more frequently observed in tumors with mutated ras (14.3%) than in tumors without mutation (3.1%).


Assuntos
Carcinoma/genética , Genes ras , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias da Bexiga Urinária/genética , Animais , Ácido Ascórbico , Sequência de Bases , Western Blotting , Carcinógenos , Carcinoma/induzido quimicamente , Carcinoma de Células de Transição/induzido quimicamente , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/patologia , DNA de Neoplasias/genética , FANFT , Masculino , Mutação , Ratos , Ratos Endogâmicos F344 , Sacarina , Neoplasias da Bexiga Urinária/induzido quimicamente
18.
Biochim Biophys Acta ; 1427(3): 408-16, 1999 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-10350657

RESUMO

BCNT, named after Bucentaur, is a protein that contains a 324-amino-acid region derived from part of a long interspersed DNA sequence element (LINE) in Ruminantia. However, the unique portion is completely missing in human and mouse BCNTs. Since no significant information on their function has been obtained by homology search, we at first examined cellular localization and biochemical characteristics of bovine BCNT to get a hint on its function. Subcellular fractionation and immunohistochemical analyses using a normal bovine epithelial cell line and bovine brain revealed that a significant amount of bovine BCNT is localized in the nuclei, while the major portion is present in the cytosol. Furthermore, it was shown that bovine BCNT is a phosphoprotein and that both bovine and human BCNTs are phosphorylated by casein kinase II in vitro. These results show that BCNTs consist of a unique family, probably a substrate of casein kinase II, which may contribute further to the understanding of gene evolution.


Assuntos
Encéfalo/metabolismo , Núcleo Celular/metabolismo , Rim/metabolismo , Fosfoproteínas/análise , Ruminantes/genética , Sequência de Aminoácidos , Animais , Bovinos , Fracionamento Celular , Linhagem Celular , DNA/química , Cervos , Imuno-Histoquímica , Fígado/metabolismo , Dados de Sequência Molecular , Proteínas Nucleares , Fosfoproteínas/genética , Fosfoproteínas/isolamento & purificação , Testes de Precipitina , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência de Aminoácidos
20.
Clin Cancer Res ; 7(11): 3437-43, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11705860

RESUMO

PURPOSE: METH-1/hADAMTS-1 and METH-2/hADAMTS-8 are recently identified genes that inhibit angiogenesis, and the murine homologue, ADAMTS-1, shows metalloproteinase function. Because the significance of METH-1 and METH-2 has not been determined in solid tumors, we examined the mRNA expressions of these molecules in pancreatic cancer and hepatocellular carcinoma (HCC). EXPERIMENTAL DESIGN: METH-1 and METH-2 mRNA expressions were identified in six pancreatic cancer cell lines and were quantified by TaqMan reverse transcription-PCR in 18 paired samples of pancreatic cancer and surrounding noncancerous pancreas, and in 14 samples of pancreatic cancer. METH-1 mRNA expression was also examined in 16 pairs of HCC and cirrhotic liver. Vascularity was estimated by CD34 staining. The correlation between clinicopathological factors and METH-1 expression was additionally analyzed. RESULTS: Four of six pancreatic cancer cell lines expressed METH-1, and 1/6 expressed METH-2. METH-1 was substantially expressed in both pancreatic cancer and noncancerous pancreas, but METH-2 was not. METH-1 expression in pancreatic cancer tissue was significantly lower than that in noncancerous pancreas (P = 0.002), and a similar result was obtained between HCC and cirrhotic liver (P = 0.003). METH-1 expression did not show a significant correlation with vascularity in pancreatic cancer or in HCC. However, pancreatic cancer with higher expression of METH-1 showed significantly severe lymph node metastasis or retroperitoneal invasion (P = 0.033 and P = 0.018, respectively) and worse prognosis (P = 0.038). CONCLUSIONS: METH-1, which was initially reported to have a potent antiangiogenic effect, does not seem to be a predominant determinant of tumor vascularity in pancreatic cancer. Rather, METH-1 seems to be involved in progression of pancreatic cancer through local invasion and lymph node metastasis.


Assuntos
Carcinoma Ductal Pancreático/patologia , Desintegrinas , Metaloendopeptidases/genética , Neoplasias Pancreáticas/patologia , Proteínas ADAM , Proteínas ADAMTS , Proteína ADAMTS1 , Idoso , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Ductal Pancreático/irrigação sanguínea , Carcinoma Ductal Pancreático/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/genética , RNA/genética , RNA/metabolismo , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Células Tumorais Cultivadas
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