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1.
Eur Radiol ; 33(7): 4713-4722, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36735038

RESUMO

OBJECTIVES: To examine the radiological patterns specifically associated with hypoxemic respiratory failure in patients with coronavirus disease (COVID-19). METHODS: We enrolled patients with COVID-19 confirmed by qPCR in this prospective observational cohort study. We explored the association of clinical, radiological, and microbiological data with the development of hypoxemic respiratory failure after COVID-19 onset. Semi-quantitative CT scores and dominant CT patterns were retrospectively determined for each patient. The microbiological evaluation included checking the SARS-CoV-2 viral load by qPCR using nasal swab and serum specimens. RESULTS: Of the 214 eligible patients, 75 developed hypoxemic respiratory failure and 139 did not. The CT score was significantly higher in patients who developed hypoxemic respiratory failure than in those did not (median [interquartile range]: 9 [6-14] vs 0 [0-3]; p < 0.001). The dominant CT patterns were subpleural ground-glass opacities (GGOs) extending beyond the segmental area (n = 44); defined as "extended GGOs." Multivariable analysis showed that hypoxemic respiratory failure was significantly associated with extended GGOs (odds ratio [OR] 29.6; 95% confidence interval [CI], 9.3-120; p < 0.001), and a CT score > 4 (OR 12.7; 95% CI, 5.3-33; p < 0.001). The incidence of RNAemia was significantly higher in patients with extended GGOs (58.3%) than in those without any pulmonary lesion (14.7%; p < 0.001). CONCLUSIONS: Extended GGOs along the subpleural area were strongly associated with hypoxemia and viremia in patients with COVID-19. KEY POINTS: • Extended ground-glass opacities (GGOs) along the subpleural area and a CT score > 4, in the early phase of COVID-19, were independently associated with the development of hypoxemic respiratory failure. • The absence of pulmonary lesions on CT in the early phase of COVID-19 was associated with a lower risk of developing hypoxemic respiratory failure. • Compared to patients with other CT findings, the extended GGOs and a higher CT score were also associated with a higher incidence of RNAemia.


Assuntos
COVID-19 , Insuficiência Respiratória , Humanos , SARS-CoV-2 , COVID-19/patologia , Estudos Retrospectivos , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Pulmão/patologia , Insuficiência Respiratória/diagnóstico por imagem , Insuficiência Respiratória/patologia
2.
Pharmazie ; 73(9): 545-552, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30223940

RESUMO

The aim of this study was to clarify the clinic-level factors related to experiences of and attitudes toward collaboration with community pharmacies. We conducted a postal questionnaire survey of all clinics in Gifu, Japan, assessing the experiences and attitudes of representative clinical staff regarding the following activities in collaboration with community pharmacists: regional care meetings/service adjustment meetings, case study conferences, joint workshops/continuing education conferences, community services, information sharing through medical cooperation networks, and accompanying community pharmacists during home care. The factors significantly related to experiences of joint workshops/continuing education conferences included home care visits (odds ratio [OR] 2.39) and a 100 % out-of-hospital prescription ratio (OR 4.80). In contrast, only home care visits were significantly associated with consideration of information sharing through medical cooperation networks and accompanying community pharmacists during home care (OR 2.06 and 11.91, respectively). Finally, the factors significantly associated with considering implementing case study conferences and joint workshops/continuing education conferences included home care visits (OR 4.64 and 2.98, respectively) and a 100% out-of-hospital prescription ratio (OR 4.64 and 6.38). Overall, having more opportunities to communicate with community pharmacists and other healthcare professionals appeared to facilitate clinics' consideration of collaboration with community pharmacies, along with actual experiences.


Assuntos
Serviços Comunitários de Farmácia/organização & administração , Comportamento Cooperativo , Pessoal de Saúde/estatística & dados numéricos , Farmacêuticos/organização & administração , Instituições de Assistência Ambulatorial/organização & administração , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Atitude do Pessoal de Saúde , Pessoal de Saúde/organização & administração , Humanos , Comunicação Interdisciplinar , Relações Interprofissionais , Japão , Inquéritos e Questionários
4.
Am J Transplant ; 14(6): 1290-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24731050

RESUMO

Blocking the CD40-CD154 interaction is reported to be effective for transplantation management and autoimmune disease models in rodents and nonhuman primates. However, clinical trials with anti-CD154 mAbs were halted because of high incidence of thromboembolic complications. Thus, we generated and characterized a fully human anti-CD40 mAb ASKP1240, as an alternative to anti-CD154 mAb. In vitro ASKP1240 concentration-dependently inhibited human peripheral blood mononuclear cell proliferation induced by soluble CD154. In addition, ASKP1240 did not destabilize platelet thrombi under physiological high shear conditions while mouse anti-human CD154 mAb (mu5C8) did. And ASKP1240 itself did not activate platelet and endothelial cells. In vivo administration of ASKP1240 (1 or 10 mg/kg, intravenously) to cynomolgus monkeys, weekly for 3 weeks, significantly attenuated both delayed-type hypersensitivity and specific antibody formation evoked by tetanus toxoid. The immunosuppressive effect was well correlated with the CD40 receptor saturation. Thus, these results suggest that ASKP1240 is immunosuppressive but not prothromboembolic, and as such appears to be a promising therapeutic candidate for the management of solid organ transplant rejection and autoimmune diseases therapy.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos CD40/imunologia , Imunossupressores/farmacologia , Animais , Anticorpos Monoclonais Humanizados , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Reações Cruzadas , Citometria de Fluxo , Humanos , Hipersensibilidade Tardia/tratamento farmacológico , Hipersensibilidade Tardia/imunologia , Imunossupressores/imunologia , Macaca fascicularis , Camundongos
5.
Pharmazie ; 67(10): 862-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23136722

RESUMO

Cell death of human breast cancer cell line MCF-7/pDsRed2-Mito, caused by independent- or multi-administration of three anticancer drugs, cyclophosphamide [CPA], doxorubicin [DXR], and 5-fluorouracil [5-FU], was studied using fluorescence and electron microscopy. In our previous study using cell viability assays, microscopic inspection of heterochromatin condensation, a DNA fragmentation assay, and flow cytometric analyses, the death of MCF-7 cells was classified into two groups. The cell death induced by CPA or 5-FU was classified as apoptotic, while the cell death induced by DXR treatment or a mixture of all three anticancer drugs was classified as non-apoptotic. Here, we examined the morphology of the whole cell and its organelles, including the mitochondria, using electron microscopy. Mitochondria are of particular interest because they are the key organelle for the molecular apoptotic-death cascade. To monitor mitochondrial morphology, we used our previously constructed MCF-7/pDsRed2-Mito line, generated by introducing the pDsRed2-Mito vector into MCF-7 cells. The mitochondria in these cells emit red fluorescence. We found that the administration of DXR alone or of all three anticancer drugs together resulted in the clumping of the red-fluorescent materials on both sides of the round dying cells, interrupted by the nucleus. Detailed electron microscopic observation revealed that the novel morphology of the dying MCF-7 cells might be owing, not to destruction of the mitochondrial membrane, but to the tight structure of the nuclear membrane. Other anticancer drugs showed different, characteristic features in electron microscopic images, which suggested that death induced by anti-cancer drugs in the human breast cancer cell line, MCF-7, may result from any of a number of diverse processes.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Antibióticos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Antineoplásicos Alquilantes/farmacologia , Neoplasias da Mama/ultraestrutura , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Ciclofosfamida/farmacologia , Doxorrubicina/farmacologia , Feminino , Corantes Fluorescentes , Fluoruracila/farmacologia , Humanos , Células MCF-7 , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência
6.
Surg Case Rep ; 8(1): 220, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36484868

RESUMO

BACKGROUND: Follicular dendritic cell sarcoma is a rare stromal tumor with no standard treatment. However, some reports have revealed that follicular dendritic cell sarcoma has an inflammatory pseudotumor variant associated with Epstein-Barr virus infection that has a relatively good prognosis. In this report, we present a case of a resected inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver, and have reviewed the literature on the clinicopathological, molecular, and genomic features of this tumor. CASE PRESENTATION: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma originates only in the liver or spleen, causes no symptoms, and is more common in middle-aged Asian women. It has no characteristic imaging features, which partially explains why the inflammatory pseudotumor variant of follicular dendritic cell sarcoma is difficult to diagnose. Pathologically, the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has spindle cells mixed with inflammatory cells and is variably positive for follicular dendritic cell markers (CD21, CD23, and CD35) and Epstein-Barr virus-encoded RNA. On genetic analysis, patients with this tumor high levels of latent membrane protein 1 gene expression and extremely low levels of host C-X-C Chemokine Receptor type 7 gene expression, indicating that the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has a latent Epstein-Barr virus type 2 infection. CONCLUSIONS: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma is an Epstein-Barr virus-associated tumor and a favorable prognosis by surgical resection, similar to Epstein-Barr virus-associated gastric cancer.

7.
Rev Sci Instrum ; 79(2 Pt 2): 02A506, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315127

RESUMO

A cesium-free H(-) ion source driven with a LaB(6) filament was developed for the J-PARC. It was operated for the J-PARC linac beam commissioning, which was started on 20 November 2006. Eight runs of 2 or 3 week beam commissioning were done until the end of June 2007. The source was mainly operated with a duty factor of 0.8% (320 micros and 25 Hz) while providing a 5 mA beam typically. Each interval of the runs, precise optimizations, such as the filament position, and so on, are examined. At present, a H(-) beam with a current of 38 mA and a rms normalized emittance of 0.22 pi mm mrad is extracted with a duty factor of 0.8% (320 micros and 25 Hz).

8.
Poult Sci ; 97(10): 3577-3586, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29850863

RESUMO

Paddy rice is a potential feed grain for chickens, whose strong gizzards can crush the hull. Here, we investigated whether paddy rice rich in hull-derived water-insoluble dietary fiber stimulates intestinal mucin secretion and production, as well as the possible involvement of paddy rice in intestinal barrier function. Layer male chicks at 7 d of age were divided into four groups according to the diet: corn, polished rice, brown rice, or paddy rice (650 g/kg diet), which they ate for 14 consecutive days. At 21 d of age, the birds were refed their experimental diets, and small intestinal mucin fractions were collected to determine intestinal mucin content. Small intestinal mucin secretion was induced most strongly in the paddy rice group (Experiment 1). The rank order of diet-induced mucin secretion was paddy rice > corn = brown rice > polished rice. Ileal MUC2 gene expression and ileal number of goblet cells were highest in the paddy rice group (Experiment 1). A study of bromodeoxy-U uptake into ileal epithelial cells indicated the increase in goblet cells in the paddy rice group was related to accelerate epithelial cell migration (Experiment 2). A single supplementation of isolated rice hulls without kernels increased MUC2 gene expression and goblet cell numbers (Experiment 3), suggesting the importance of the hull's bulk-forming capacity on mucin production. Finally, chicks fed corn or paddy rice were orally administered dextran sodium sulfate (DSS) to disrupt intestinal barrier function. In the DSS-treated birds, the intestinal permeability of fluorescein isothiocyanate dextran in the everted gut sacs was much lower in the paddy rice group than in the corn group (Experiment 4), showing that paddy rice protects against mucosal disruption. In conclusion, ingestion of paddy rice increases intestinal mucin secretion and production through enhanced MUC2 gene expression and epithelial turnover and prevents DSS-induced intestinal barrier defects in chickens.


Assuntos
Proteínas Aviárias/metabolismo , Galinhas/metabolismo , Sulfato de Dextrana/toxicidade , Mucosa Intestinal/metabolismo , Mucina-2/metabolismo , Oryza/química , Ração Animal/análise , Animais , Dieta/veterinária , Células Caliciformes/citologia , Intestinos/efeitos dos fármacos , Masculino , Oryza/classificação , Zea mays/química
9.
J Clin Invest ; 79(1): 301-4, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3793929

RESUMO

Complementary DNA (cDNA) clones specific for phospholamban of sarcoplasmic reticulum membranes have been isolated from a canine cardiac cDNA library. The amino acid sequence deduced from the cDNA sequence indicates that phospholamban consists of 52 amino acid residues and lacks an amino-terminal signal sequence. The protein has an inferred mol wt 6,080 that is in agreement with its apparent monomeric mol wt 6,000, estimated previously by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Phospholamban contains two distinct domains, a hydrophilic region at the amino terminus (domain I) and a hydrophobic region at the carboxy terminus (domain II). We propose that domain I is localized at the cytoplasmic surface and offers phosphorylatable sites whereas domain II is anchored into the sarcoplasmic reticulum membrane.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA/genética , Cães , Peso Molecular , Miocárdio/análise , Conformação Proteica , Solubilidade
10.
Eur J Ophthalmol ; 17(3): 392-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17534822

RESUMO

PURPOSE: To investigate intraoperative visibility and long-term clinical outcome following triamcinolone acetonide (TA)-assisted pars plana vitrectomy (PPV) for proliferative vitreoretinopathy (PVR). METHODS: A retrospective interventional noncomparative clinical study was carried out on 21 eyes from 21 patients with more than grade C2 PVR, all of whom underwent TA-assisted PPV. Two of the specimens were observed with an electron microscope. After treatment, outcome measures, including changes in best-corrected visual acuity (BCVA), intraocular pressure (IOP) elevation, corneal pathology, and occurrence of endophthalmitis, were recorded. Patient follow-up time was >36 months (mean +/-standard deviation = 47.3 +/- 6.7 months). RESULTS: TA improved the intraoperative visualization of the epiretinal membrane (ERM), allowing it to be easily removed together with the partially internal limiting membrane (ILM) using micro forceps. The excised tissue consisted of proliferative cells and an extracellular matrix underlying the ILM. After the operation, 71.4% of the eyes had improved BCVA. Three of the eyes showed sustained IOP elevation (14.3%); two of these cases were controlled by the administration of eyedrops, while the third required filtering surgery. In two cases, an absorption delay of the TA granule on the retinal surface was observed. One eye developed corneal stromal opacity. No other severe complications occurred during the observation period. CONCLUSIONS: TA-assisted PPV offers improved visualization during the surgical management of PVR, and allows surgeons to excise the ERM safely and effectively without the risk of serious complications.


Assuntos
Glucocorticoides/uso terapêutico , Triancinolona Acetonida/uso terapêutico , Vitrectomia/métodos , Vitreorretinopatia Proliferativa/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Membrana Epirretiniana/patologia , Membrana Epirretiniana/cirurgia , Feminino , Seguimentos , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual , Vitreorretinopatia Proliferativa/tratamento farmacológico , Vitreorretinopatia Proliferativa/cirurgia
11.
Structure ; 8(9): 915-25, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10986459

RESUMO

BACKGROUND: Conformational alteration and fibril formation of proteins have a key role in a variety of amyloid diseases. A simplified model peptide would lead to a better understanding of underlying mechanisms whereby protein misfolding and aggregation occur. Recently, we reported the design of peptides that undergo a self-initiated structural transition from an alpha helix to a beta sheet and form amyloid fibrils. In this study, we focus on two glutamine residues in the peptide, and report a mutational analysis of these residues. RESULTS: A coiled-coil alpha-helix structure bearing a hydrophobic adamantanecarbonyl (Ad) group at the N terminus was designed (parent peptide Ad-QQ). In neutral aqueous solution, the double Gln-->Ala mutant (Ad-AA) underwent the alpha-->beta structural transition within four hours, which was similar to the case of Ad-QQ. In contrast, two kinds of single Gln-->Ala mutant (Ad-QA and Ad-AQ) required three days for the transition. Furthermore, Ad-QQ and Ad-AA formed amyloid fibrils, whereas Ad-QA and Ad-AQ did not. Interestingly, however, Ad-QA and Ad-AQ complementarily assembled into the fibrils when they were mixed. CONCLUSIONS: The Gln-->Ala substitution in the peptide significantly alters the alpha-->beta transitional properties and the ability to form amyloid fibrils. A heterogeneous assembly of two peptide species into the fibrils is also presented. These results suggest that the secondary structural transition and self-assembly into the well-organized fibril may depend strictly on the primary structure, which determines the beta-sheet packing. The results might provide insights into misfolding and fibril formation of disease-associated mutant proteins.


Assuntos
Amiloide/química , Peptídeos/química , Sequência de Aminoácidos , Dicroísmo Circular , Cinética , Microscopia Eletrônica , Dados de Sequência Molecular , Peptídeos/síntese química , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade
12.
Eur J Ophthalmol ; 16(2): 279-86, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16703547

RESUMO

PURPOSE: To evaluate the results and complications of combined pars plana vitrectomy (PPV), phacoemulsification and aspiration (PEA), and intraocular lens (IOL) implantation. METHODS: A total of 117 eyes from 114 patients who had undergone PPV combined with PEA and IOL implantation were retrospectively analyzed. Combined surgery was performed for a wide variety of vitreoretinal diseases. Intraoperative and postoperative complications were also reviewed. RESULTS: The postoperative BCVA improved by 2 lines or more in 85 eyes (72.6%). Intraoperative complications consisted of retinal tears in 14 eyes (12.0%) and posterior capsular rupture in 2 eyes (1.7%). Iatrogenic retinal tears occurred more frequently in eyes with a macular hole than in eyes with any other disease (p=0.005, chi-square test). Postoperative complications consisted of posterior capsule opacification (PCO) (21 eyes), transient IOP elevation (29 eyes), vitreous hemorrhage (6 eyes), anterior chamber fibrin exudation (11 eyes), posterior iris synechia (8 eyes), neovascular glaucoma (1 eye), and recurrent retinal detachment (RD) (2 eyes). Fibrin exudation occurred more frequently in eyes with proliferative diabetic retinopathy (PDR) and RD than in eyes with any other disease (p=0.03, chi-square test). PCO occurred more frequently in eyes with PDR than in eyes with any other disease (p=0.03, chi-square test). CONCLUSIONS: The present study suggests that a high success rate can be achieved when recently improved PPV techniques are combined wi th PEA and IOL implantation. The complications that were observed following this combined treatment varied with respect to the vitreoretinal disease present prior to surgery.


Assuntos
Oftalmopatias/cirurgia , Implante de Lente Intraocular/métodos , Facoemulsificação/métodos , Doenças Retinianas/cirurgia , Vitrectomia/métodos , Corpo Vítreo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual/fisiologia
13.
Cancer Res ; 46(2): 770-7, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3000585

RESUMO

A human salivary gland adenocarcinoma cell line, which has ultrastructure and biological markers specific to the intercalated duct cells of human salivary glands, was cultured in 5 mM sodium butyrate for 12 days; then the cells were trypsinized, subcultured for an additional 16 days, and then transferred to growth medium without sodium butyrate. Morphological changes appeared about 1 wk after return to growth medium without sodium butyrate; cells being spindle or stellate in shape appeared in the treated cells, whereas the untreated cells were polygonal in shape. This morphologically altered phenotype persists after more than 14 mo of culture in growth medium without sodium butyrate. Of 40 subclones isolated, 2 clonal cell lines were established from the subculture and characterized. The other 38 subclones were accompanied by cell death during the subcultures. The clonal lines exhibited a phenotype similar to myoepithelial cells such as myosin, beta-chain of S-100 protein, myofilaments, and oxytocin receptor in addition to decreased tumorigenicity and anchorage-independent growth. These findings indicate that commitment to differentiation into myoepithelial cells and conversion from malignant to normal phenotype occur in a human salivary gland adenocarcinoma cell line following the sodium butyrate treatment.


Assuntos
Adenocarcinoma/patologia , Butiratos/farmacologia , Neoplasias das Glândulas Salivares/patologia , Animais , Ácido Butírico , Antígeno Carcinoembrionário/metabolismo , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Clonais/patologia , Técnicas de Cultura , Epitélio/metabolismo , Humanos , Camundongos , Camundongos Nus , Miosinas/metabolismo , Receptores de Angiotensina/metabolismo , Receptores de Ocitocina , Proteínas S100/metabolismo
14.
Cancer Res ; 45(8): 3878-90, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2410104

RESUMO

The adenocarcinoma cell line HSG from human salivary gland, which proliferates in vitro or in nude mice, was examined by the immunoperoxidase method for the expression of three different types of intermediate-sized filaments (IFs) and of specific antigens such as carcinoembryonic antigen, S-100 protein, secretory component, lactoferrin, myosin, tropomyosin, and actin. The cultured HSG cells were found to express three different types of IFs defined by antibodies to keratin, vimentin, and desmin. In HSG cells proliferating in vitro at 34 degrees C and 37 degrees C but not at 39 degrees C, the expression of tropomyosin and carcinoembryonic antigen was observed, although myosin and S-100 protein were not detected. The expressions of actin, lactoferrin, and secretory component were restricted to cultured HSG cells at 39 degrees C and 37 degrees C, respectively. Transplantation of HSG cells into nude mice resulted in the establishment of a nude mouse system with malignant characteristics such as invasion and metastasis. The expression of IFs in the primary tumors was restricted to keratin and desmin IFs, whereas coexpression of keratin, vimentin, and desmin IFs was observed in some neoplastic cells present in the metastatic tumors in regional lymph nodes and lung. In addition, expression of actin, myosin, tropomyosin, and S-100 protein was found in the metastatic tumors, whereas myosin and S-100 protein were not detected in the primary tumors. Moreover, the metastatic tumors were almost occupied by the neoplastic cells with oncocytic changes, although oncocytic change was not found in the cultured HSG cells and their primary tumors.


Assuntos
Adenocarcinoma/análise , Antígenos de Neoplasias/análise , Citoesqueleto/ultraestrutura , Neoplasias das Glândulas Salivares/análise , Adenocarcinoma/ultraestrutura , Animais , Antígeno Carcinoembrionário/análise , Linhagem Celular , Desmina/análise , Feminino , Humanos , Queratinas/análise , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Proteínas S100/análise , Neoplasias das Glândulas Salivares/ultraestrutura , Componente Secretório/análise , Transplante Heterólogo , Vimentina/análise
15.
Cancer Res ; 54(4): 1092-7, 1994 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-8313366

RESUMO

Amsacrine, [4'-(9-acridinylamino)-methanesulfon-m-auisidide], belongs to the class of cancer chemotherapeutic agents that target DNA topoisomerase II. We show that, over its cytotoxic range, amsacrine is a potent mutagen of the S1 phenotype in the AL (human x hamster) hybrid cell line. By contrast, amsacrine induction of the HPRT- phenotype in AL cells is at least two decades less frequent and is not concentration dependent. Such differential mutation frequencies are hypothesized to reflect the concomitant loss of essential genes neighboring the hprt locus. It may be that some amsacrine cytotoxicity is due to the inactivation of essential genes by large deletions. The AL mutation system is well suited for the detection and mapping of mutations which are large deletions because its MIC1 locus, which controls the expression of the selectable cell surface antigen S1, is on a single human chromosome. This human chromosome 11 is in addition to the genome of the Chinese hamster ovary cell and is basically nonessential. Since there are no sister human chromosomes in AL cells, deletions which extend beyond the MIC1 locus may be conveniently and unambiguously mapped. We have detected the presence or absence of 9 different chromosome 11 markers in 48 S1- mutants cloned from amsacrine-treated cultures. We find that almost all (92%) of the mutants have deletions of at least 1.5-2 megabase pairs in length. The distribution of marker loss frequencies flanking the MIC1 locus does not appear symmetric with respect to distance from that locus. We speculate that amsacrine-induced deletions are mediated by a series of subunit exchanges between overlapping topoisomerase II dimers at the bases of replicons or larger chromosomal structures such as replicon clusters or chromosome minibands.


Assuntos
Amsacrina/farmacologia , Deleção Cromossômica , Inibidores da Topoisomerase II , Sequência de Bases , Células Cultivadas , Mapeamento Cromossômico , DNA Topoisomerases Tipo II/fisiologia , Marcadores Genéticos , Hipoxantina Fosforribosiltransferase/genética , Dados de Sequência Molecular , Mutação , Timidina Quinase/genética
16.
Cancer Res ; 45(12 Pt 1): 6160-7, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2998594

RESUMO

Neoplastic intercalated duct cells that originated from a human submandibular salivary gland release transforming growth factor and human epidermal growth factor into serum-free medium. The transforming growth factor with the soft agar colony-forming activity when assayed in the presence of mouse epidermal growth factor on normal rat kidney clone 49F indicator cells, but without mitogenic action to quiescent 3T3 cells, does not compete with epidermal growth factor for receptor binding, is heat and acid resistant but trypsin and dithiothreitol sensitive, and therefore is of the transforming growth factor-beta class. The immunoreactive human epidermal growth factor is detected by radioimmunoassay on certain fractions obtained by the Bio-Gel P-60 chromatography of neoplastic epithelial duct cells originated from a human submandibular salivary gland-conditioned medium and is biologically very similar to mouse epidermal growth factor. Moreover, the presence of human epidermal growth factor in cultured neoplastic epithelial duct cells originated from a human submandibular salivary gland is demonstrated by the peroxidase:antiperoxidase method.


Assuntos
Adenocarcinoma/metabolismo , Fator de Crescimento Epidérmico/biossíntese , Substâncias de Crescimento/biossíntese , Biossíntese Peptídica , Neoplasias das Glândulas Salivares/metabolismo , Divisão Celular , Linhagem Celular , Meios de Cultura , Fator de Crescimento Epidérmico/isolamento & purificação , Receptores ErbB , Substâncias de Crescimento/isolamento & purificação , Humanos , Peptídeos/isolamento & purificação , Receptores de Superfície Celular/metabolismo , Fatores de Crescimento Transformadores
17.
Rev Sci Instrum ; 87(2): 02B129, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932011

RESUMO

The Japan Proton Accelerator Research Complex (J-PARC) cesiated RF-driven H(-) ion source has been successfully operated for about 1 yr. By the world brightest level beam, the J-PARC design beam power of 1 MW was successfully demonstrated. Although no internal-RF-antenna failure, except for the once caused by an excess cesium due to a misoperation, occurred in the operation, many antennas failed in pre-conditionings for the first hundred days. The antenna failure rate was drastically decreased by using an antenna with coating thicker than a standard value and the pre-conditioning procedure repeating 15 min 25 kW RF-power operation and impurity-gas evacuation a few times, before the full power (50 kW) operation.

18.
Rev Sci Instrum ; 87(2): 02B130, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932012

RESUMO

The Japan Proton Accelerator Research Complex (J-PARC) cesiated RF-driven H(-) ion source has been successfully operated for about one year. By the world's brightest level beam, the J-PARC design beam power of 1 MW was successfully demonstrated. In order to minimize the transverse emittances, the rod-filter-field (RFF) was optimized by changing the triple-gap-lengths of each of pairing five piece rod-filter-magnets. The larger emittance degradation seems to be caused by impurity-gases than the RFF. The smaller beam-hole-diameter of the extraction electrode caused the more than expected improvements on not only the emittances but also the peak beam intensity.

19.
Rev Sci Instrum ; 87(2): 02B138, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932020

RESUMO

For the upgrade of the Japan Proton Accelerator Research Complex linac beam current, a cesiated RF-driven negative hydrogen ion source was installed during the 2014 summer shutdown period, with subsequent operations commencing on September 29, 2014. The ion source has been successfully operating with a beam current and duty factor of 33 mA and 1.25% (500 µs and 25 Hz), respectively. The result of recent beam operation has demonstrated that the ion source is capable of continuous operation for approximately 1100 h. The spark rate at the beam extractor was observed to be at a frequency of less than once a day, which is an acceptable level for user operation. Although an antenna failure occurred during operation on October 26, 2014, no subsequent serious issues have occurred since then.

20.
Rev Sci Instrum ; 87(2): 02B128, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932010

RESUMO

A numerical model of plasma transport and electromagnetic field in the J-PARC (Japan Proton Accelerator Research Complex) radio frequency ion source has been developed to understand the relation between antenna coil heat loadings and plasma production/transport processes. From the calculation, the local plasma density increase is observed in the region close to the antenna coil. Electrons are magnetized by the magnetic field line with absolute magnetic flux density 30-120 Gauss which leads to high local ionization rate. The results suggest that modification of magnetic configuration can be made to reduce plasma heat flux onto the antenna.

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