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1.
Ultrasound Obstet Gynecol ; 37(3): 277-82, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21337653

RESUMO

OBJECTIVES: To document outcome and to explore prognostic factors in fetal left congenital diaphragmatic hernia (CDH). METHODS: This was a multicenter retrospective study of 109 patients with prenatally diagnosed isolated left CDH born between 2002 and 2007. The primary outcome was intact discharge, defined as discharge from hospital without major morbidities, such as a need for respiratory support including oxygen supplementation, tube feeding, parenteral nutrition or vasodilators. All patients were managed at perinatal centers with immediate resuscitation, gentle ventilation (mostly with high-frequency oscillatory ventilation) and surgery after stabilization. Prenatal data collected included liver and stomach position, lung-to-head ratio, gestational age at diagnosis and presence or absence of polyhydramnios. Stomach position was classified into four grades: Grade 0, abdominal; Grade 1, left thoracic; Grade 2, less than half of the stomach herniated into the right chest; and Grade 3, more than half of the stomach herniated into the right chest. RESULTS: Overall intact discharge and 90-day survival rates were 65.1% and 79.8%, respectively. Stomach herniation was classified as Grade 0 in 19.3% of cases, Grade 1 in 45.9%, Grade 2 in 13.8% and Grade 3 in 21.1%. Multivariate analysis revealed that liver position was the strongest prognostic variable for intact discharge, followed by stomach position. Based on our results, we divided patients into three groups according to liver (up vs. down) and stomach (Grade 0-2 vs. Grade 3) position. Intact discharge rates declined significantly from liver-down (Group I), to liver-up with stomach Grade 0-2 (Group II), to liver-up with stomach Grade 3 (Group III) (87.0%, 47.4% and 9.5% of cases, respectively). CONCLUSION: Current status and outcomes of prenatally diagnosed left CDH in Japan were surveyed. Stomach herniation into the right chest was not uncommon and its grade correlated with outcome. The combination of liver and stomach positions was useful to stratify patients into three groups (Group I-III) with different prognoses.


Assuntos
Estômago/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Feminino , Idade Gestacional , Hérnia Diafragmática/diagnóstico por imagem , Hérnia Diafragmática/embriologia , Hérnia Diafragmática/mortalidade , Hérnias Diafragmáticas Congênitas , Humanos , Recém-Nascido , Japão/epidemiologia , Masculino , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Prognóstico , Respiração Artificial , Estudos Retrospectivos , Estômago/anatomia & histologia , Estômago/embriologia , Taxa de Sobrevida
2.
Clin Cancer Res ; 7(4): 901-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11309340

RESUMO

Hepatoblastoma (HBL) is the most common malignant liver tumor in young children. Recent reports have shown that the beta-catenin gene was frequently mutated or deleted in HBLS: To elucidate the role of beta-catenin abnormalities in HBLs, we searched for mutations of beta-catenin and APC as well as expression of the target genes, cyclin D1, c-myc, and fibronectin, in 68 primary HBLS: The mutation analysis revealed that 44 (65%) tumors carried missense mutations or deletions of beta-catenin, all of which were somatic and targeted to the exon 3 encoding the amino acid residues involved in its degradation. However, no loss of function mutation of the APC gene was detected by the yeast functional assay. Of interest, beta-catenin mutation was significantly correlated with overexpression of the target genes, cyclin D1 and fibronectin, but not with that of c-myc in HBLs as measured by quantitative real-time reverse transcription-PCR. The immunohistochemical studies in 15 HBLs demonstrated that the nuclear/cytoplasmic accumulation of beta-catenin was positive in 13 tumors, 9 of which had the deletion or mutation of the gene. The significant correlation between the beta-catenin gene abnormality and the positive staining of cyclin D1 was also confirmed. Furthermore, the nuclear accumulation of beta-catenin was strongly associated with the poorly differentiated tumor cell components as well as with the positive staining of cyclin D1 within the tumor. Thus, our present results suggested that the gain of function mutation of beta-catenin played a crucial role in the malignant progression of HBL in vivo.


Assuntos
Ciclina D1/metabolismo , Proteínas do Citoesqueleto/genética , Fibronectinas/metabolismo , Deleção de Genes , Hepatoblastoma/genética , Transativadores , Proteína da Polipose Adenomatosa do Colo , Diferenciação Celular , Criança , Pré-Escolar , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Humanos , Imuno-Histoquímica , Lactente , Estatística como Assunto , beta Catenina
3.
Med Pediatr Oncol ; 35(6): 516-21, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11107106

RESUMO

BACKGROUND: We have identified for the first time a homozygously deleted region within the smallest region of overlap at 1p36.2-3 in two neuroblastoma cell lines. PROCEDURE: The 800-kb PAC contig covering the entire homozygously deleted region was made and sequenced. To date, approximately 70% of sequencing has been accomplished, and the estimated length of the deleted region was 500 kb. RESULTS: Currently, we have found six genes within the region, which include three known genes as well as three other genes that have been reported during processing of our present project for the last 3(1/2) years. We report here the results of expression and mutation analyses of those genes. CONCLUSIONS: Full sequencing for the region of homozygous deletion as well as further analyses of the genes mapped within the region may reveal whether or not there is a neuroblastoma suppressor gene as proposed by the Knudson's two-hit hypothesis.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Homozigoto , Neuroblastoma/genética , Pré-Escolar , Mapeamento Cromossômico , Expressão Gênica , Humanos , Perda de Heterozigosidade , Células Tumorais Cultivadas
4.
Med Pediatr Oncol ; 35(6): 547-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11107114

RESUMO

BACKGROUND: Neuroblastoma (NBL) has a distinct nature in different prognostic subgroups. PROCEDURE: To understand the molecular mechanism of NBL's genesis and biology as well as that of the neural crest development, we constructed full-length-enriched cDNA libraries by an oligo-capping method from two different subsets of primary NBL, one with favorable biology and the other with MYCN amplification. RESULTS: Sequencing analysis of these libraries revealed that the expression profile was markedly different between both subsets. To identify the genes differentially expressed between the subsets, semi-quantitative RT-PCR analyses are proceeding. CONCLUSION: So far, 54 transcripts have been found to be expressed at high levels in favorable NBLs, and significantly at low levels in unfavorable NBLs.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Biblioteca Gênica , Neuroblastoma/genética , Humanos , Programas de Rastreamento , Células Tumorais Cultivadas
5.
Med Pediatr Oncol ; 35(6): 628-31, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11107133

RESUMO

BACKGROUND: The biology of neuroblastoma (NBL) is at least partly regulated by neurotrophic factors and their receptors. PROCEDURE: To identify novel NBL-related genes that affect growth, differentiation, and programmed cell death of the tumor, we constructed full-length-enriched cDNA libraries by oligo-capping method. RESULTS: Semi-quantitative and quantitative real-time RT-PCR showed that the nbla3145 gene was significantly highly expressed in favorable subset of NBL. The nucleo-tide sequence of nbla3145 revealed that it was a novel member of metalloproteinase, endothelin-converting enzyme, and was the same gene recently reported as XCE. We also cloned nbla3145beta which was a novel truncated form of nbla3145 (or nbla3145alpha). CONCLUSIONS: Our results suggested that nbla3145/XCE plays an important role in regulating growth and differentiation of NBL.


Assuntos
Regulação Neoplásica da Expressão Gênica , Biblioteca Gênica , Metaloendopeptidases/genética , Neuroblastoma/genética , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-11046377

RESUMO

The random multiplicative process is studied for the case of a colored multiplicative noise with exponentially decreasing autocorrelation function. We observe the power law exponent of probability distribution in a statistically steady state numerically to clarify the effect of finite correlation time. The renormalization procedure is applied to derive the power law exponent theoretically. The power law exponent is inversely proportional to the autocorrelation time of the multiplicative noise.

7.
Nihon Rinsho ; 58(9): 1886-91, 2000 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-11004821

RESUMO

Gastroesophageal reflux disease(GERD) is believed to be common and chronic gastrointestinal disorder. Quantitative estimates of the actual prevalence of GERD are difficult to obtain, because those who seek health care probably represent only a tip of the iceberg of people with GERD. The prevalence of heartburn and/or regurgitation, considered to be reasonably specific symptoms for the diagnosis of GERD, ranged from 10% to 48% for heartburn, from 9% to 45% for regurgitation and 21% to 59% for both/either in systematic review of GERD and reflux esophagitis(RE). It is widely accepted that the prevalence is lower in Asian countries, including Japan, compared with that in Western countries. However, the prevalence of RE in Japan may be increasing. In the case of heartburn and regurgitation in GERD and endoscopic findings in RE, different understandings of these terms by different investigators and subjects may have contributed to the range of results. Symptom definitions and what is understood by them should be among the most important considerations when undertaking population prevalence studies on reflux like symptoms, to allow comparisons to be made between studies.


Assuntos
Refluxo Gastroesofágico/epidemiologia , Doença Crônica , Esofagite Péptica/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Prevalência
8.
Oncogene ; 19(37): 4302-7, 2000 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-10980605

RESUMO

Loss of heterozygosity of the distal region of chromosome 1p where tumor suppressor gene(s) might harbor is frequently observed in many human cancers including neuroblastoma (NBL) with MYCN amplification and poor prognosis. We have identified for the first time a homozygously deleted region at the marker D1S244 within the smallest region of overlap at 1p36.2-p36.3 in two NBL cell lines, NB-1 and NB-C201 (MASS-NB-SCH1), although our genotyping has suggested the possibility that both lines are derived from the same origin. The 800-kb PAC contig covering the entire region of homozygous deletion was made and partially sequenced (about 60%). The estimated length of the deleted region was 500 kb. We have, thus far, identified six genes within the region which include three known genes (DFF45, PGD, and CORT) as well as three other genes which have been reported during processing our present project for the last 3(1/2) years (HDNB1/UFD2, KIAA0591F/KIF1B-beta, and PEX14). They include the genes related to apoptosis, glucose metabolism, ubiquitin-proteasome pathway, a neuronal microtubule-associated motor molecule and biogenesis of peroxisome. At least three genes (HDNB1/UFD2, KIAA0591F/KIF1B-beta, and PEX14) were differentially expressed at high levels in favorable and at low levels in unfavorable subsets of primary neuroblastoma. Since the 1p distal region is reported to be imprinted, those differentially expressed genes could be the new members of the candidate NBL suppressor, although RT-PCR-SSCP analysis has demonstrated infrequent mutation of the genes so far identified. Full-sequencing and gene prediction for the region of homozygous deletion would elucidate more detailed structure of this region and might lead to discovery of additional candidate genes. Oncogene (2000) 19, 4302 - 4307


Assuntos
Cromossomos Humanos Par 1/genética , Regulação Neoplásica da Expressão Gênica , Perda de Heterozigosidade , Neuroblastoma/genética , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Deleção de Sequência , Proteínas de Transporte/genética , Mapeamento Cromossômico , DNA Complementar/genética , Proteínas Fúngicas/genética , Deleção de Genes , Genes , Genes Supressores de Tumor , Marcadores Genéticos , Impressão Genômica , Genótipo , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Cinesinas/genética , Proteínas de Membrana/genética , N-Acetilglucosaminiltransferases/genética , Neuroblastoma/patologia , Precursores de Proteínas/genética , Células Tumorais Cultivadas , Enzimas de Conjugação de Ubiquitina
9.
Oncogene ; 19(5): 617-23, 2000 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-10698506

RESUMO

Survivin (SVV) is a family member of inhibitor of apoptosis proteins (IAPs) and its expression is cell cycle regulated. The gene is mapped to chromosome 17q25, the region of which is frequently gained in advanced stages of neuroblastoma (NBL). However, the role of SVV in NBL is poorly understood. Here we studied the clinical and biological role of SVV in NBL. A 1.9 kb SVV transcript was expressed in all of 9 NBL cell lines at higher levels than those in adult cancer cell lines. In 34 primary NBLs, high levels of SVV expression was significantly associated with age greater than 12 months (two sample t-test: P= 0.0003), advanced stages (P = 0.0136), sporadic tumors (P= 0.0027) and low levels of TrkA expression (P = 0.0030). In NBL cell lines, SVV mRNA expression was dramatically down-regulated in CHP134 and IMR32 cells undergoing apoptosis after treatment with all-trans retinoic acid (RA) or serum deprivation. It was only moderately decreased in cells (SH-SY5Y and CHP901) undergoing RA-induced differentiation. On the other hand, in proliferating NBL cells or RA-treated SK-N-AS line which is refractory to RA, the SVV mRNA remained at steady state levels or rather up-regulated. Furthermore, transfection of SVV into CHP134 cells induced remarkable inhibition of the RA-induced apoptosis. Collectively, our results suggest that high expression of SVV is a strong prognostic indicator for the advanced stage neuroblastomas, and that it could be one of the candidate genes for the 17q gain.


Assuntos
Cromossomos Humanos Par 17/genética , Proteínas Associadas aos Microtúbulos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Biossíntese de Proteínas , Proteínas/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Caspase 3 , Caspases/biossíntese , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ativação Enzimática , Indução Enzimática , Humanos , Lactente , Recém-Nascido , Proteínas Inibidoras de Apoptose , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neuroblastoma/enzimologia , Neuroblastoma/genética , Prognóstico , Fatores de Risco , Survivina , Transfecção , Tretinoína/farmacologia , Células Tumorais Cultivadas
10.
Kekkaku ; 74(7): 579-84, 1999 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-10481413

RESUMO

The present study described 2 cases of patients with duodenal tuberculosis. Case 1 was a 55 year-old Japanese male patient with pulmonary tuberculosis and past medical history of subtotal gastrectomy (Billroth II reconstruction). Tubercle bacilli were positive both on smear and culture from his sputum and feces. Because of complaining right hypochondralgia, upper gastrointestinal endoscopy was performed and revealed multiple ringed ulcers in the afferent limb of duodenum. Histopathological study of biopsy specimen demonstrated granulomatous inflammation as well as acid-fast bacilli confirmed by Ziehl-Neelsen staining. Tissue culture was positive for M. tuberculosis. Colonic tuberculosis was demonstrated by barium enema. Case 2 was a 45 year-old male patient with pulmonary tuberculosis in association with severe uncontrolled diabetes mellitus. Sputum polymerase chain reaction test was positive for M. tuberculosis. Granulomatous inflammation and positive acid-fast bacilli in biopsy specimen obtained from ulcers in the descending portion of the duodenum made a diagnosis of duodenal tuberculosis. No other intestinal tuberculous lesion was recognized. Since 1988, 11 cases of duodenal tuberculosis including the presented two cases have been reported in Japan. Most of the recent cases had tuberculous lesions in the descending portion of the duodenum and were diagnosed as duodenal tuberculosis by endoscopic examinations, while the majority of the cases reported before 1987 had tuberculosis in the more distant portions of the duodenum and were diagnosed mainly by surgical procedures.


Assuntos
Duodenopatias/diagnóstico , Tuberculose Gastrointestinal/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
11.
Tokai J Exp Clin Med ; 24(3): 117-23, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10733159

RESUMO

It is known that cutaneous electrogastrography (EGG) undergoes a change after food ingestion, showing increases in frequency and amplitude compared with preprandial values, but the factors regulating such changes remain to be elucidated. Paying special attention to gastrin, one of gastrointestinal peptides released after food ingestion, we administered tetragastrin in an exogenous manner and evaluated its effects on EGG in the present study. In healthy subjects, the intramuscular injection of tetragastrin significantly increased EGG frequency dose-dependently, but caused no significant change in amplitude. These results suggest that the increase in endogenous gastrin release is one of the mechanisms which underlies the increase in EGG frequency after food ingestion.


Assuntos
Fármacos Gastrointestinais/farmacologia , Estômago/efeitos dos fármacos , Tetragastrina/farmacologia , Adulto , Eletrofisiologia , Fármacos Gastrointestinais/administração & dosagem , Humanos , Masculino , Estômago/fisiologia , Tetragastrina/administração & dosagem , Fatores de Tempo
13.
Artif Organs ; 22(5): 426-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9609353

RESUMO

Aiming at a totally implantable ventricular assist device (VAD), a vibrating flow pump (VFP) was developed in Tohoku University. A transcutaneous energy transmission system (TETS) using an amorphous fiber was developed for the totally implantable VAD system. The VFP works with a higher frequency than the natural heart of a biological system, a frequency of 10-50 Hz. In this research, animal experiments on left heart bypass were performed with healthy goats. Blood from the apex of the left ventricle was received and was sent to the aorta so that an adequate supporting effect of the left heart was provided. In particular, the depression effect of the left ventricle was obvious. As a result, sufficient artificial heart flow was provided. For a totally implantable type VAD, left heart bypass of almost 100% may become necessary in some situations. Therefore, apex approaches of left heart bypass may be desirable. From an anatomical consideration, an apex of the heart is suitable for the VFP of this totally implantable type. In the left heart bypass for which the apex of the heart was used, an almost 100% bypass was possible. This is a requirement that is important when waiting for recovery of sufficient cardiac function. It is also important that left heart circulation is maintained fully by an artificial heart of the complete implantation type. The VFP was considered to be useful as a totally implantable type artificial heart from the results.


Assuntos
Circulação Coronária/fisiologia , Derivação Cardíaca Esquerda , Coração Auxiliar , Animais , Pressão Sanguínea/fisiologia , Desenho de Equipamento/normas , Cabras , Oscilometria , Próteses e Implantes , Vibração
14.
Artif Organs ; 21(7): 625-9, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9212928

RESUMO

For the development of a totally implantable ventricular assist system (VAS), we have been developing the vibrating flow pump (VFP), which can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for a totally implantable system. In this study, effects of left ventricular assistance with this unique oscillated blood flow were analyzed by nonlinear mathematics for evaluation as the entire circulatory regulatory system, not as a separate part of the system. Left heart bypasses using VFPs from the left atriums to the descending aortas were performed in chronic animal experiments using healthy adult goats. Electrocardiogram (ECG), arterial blood pressure, VFP pump flow, and flow of the descending aorta data taken while the goats were awake were recorded in the data recorder and analyzed in the personal computer system through the AD convertor. Using nonlinear mathematics, time series data were embedded into the phase space, and the Lyapunov numerical method, fractal dimension analysis, and power spectrum analysis were performed to evaluate the nonlinear dynamics. During left ventricular assistance with the VFP, Mayer wave fluctuations were decreased in the power spectrum, the fractal dimension of the hemodynamics was significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that nonlinear dynamics, which mediate the cardiovascular dynamics, may be affected during LV bypass with oscillated flow. Decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased the peripheral resistance. Decreased sympathetic discharges may be the origin of the decreased Mayer wave and fractal dimension. These nonlinear dynamical analyses may be useful to design the optimal VAS control.


Assuntos
Coração Auxiliar , Hemodinâmica/fisiologia , Animais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea/fisiologia , Simulação por Computador , Eletrocardiografia , Análise de Fourier , Fractais , Cabras , Derivação Cardíaca Esquerda/normas , Frequência Cardíaca/fisiologia , Modelos Biológicos , Dinâmica não Linear , Fluxo Pulsátil , Sistema Nervoso Simpático/fisiologia , Resistência Vascular/fisiologia
15.
Heart Vessels ; Suppl 12: 41-3, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9476541

RESUMO

We have developed a vibrating flow pump (VFP) that can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for a totally implantable ventricular assist system (VAS). To evaluate the newly developed VAS, left heart bypasses, using the VFP, were performed in chronic animal experiments. Hemodynamic parameters were recorded in a data recorder in healthy adult goats during an awake condition and analyzed in a personal computer system through an alternating-direct current converter. Basic performance of the total system with a transcutaneous energy transmission system were satisfactory. During left ventricular assistance with the VFP, Mayer wave fluctuations of hemodynamics were decreased in the power spectrum, the fractal dimensions of the hemodynamics were significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that cardiovascular regulatory nonlinear dynamics, which mediate the hemodynamics, may be affected by left ventricular bypass with oscillated flow. The decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased peripheral resistance. These results suggest that this newly developed VAS is useful for the totally implantable system with unique characteristics that can control hemodynamic properties.


Assuntos
Coração Artificial , Coração Auxiliar , Animais , Circulação Coronária/fisiologia , Fenômenos Eletromagnéticos , Desenho de Equipamento , Estudos de Avaliação como Assunto , Fractais , Cabras , Derivação Cardíaca Esquerda , Hemodinâmica/fisiologia , Modelos Cardiovasculares , Dinâmica não Linear , Vibração
16.
Artif Organs ; 20(7): 777-82, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8828767

RESUMO

We have studied the fluctuations of an artificial circulation for the analysis of the physiological aspects; however, the conventionally used fast Fourier transform (FFT) method cannot separate harmonic oscillations, such as respiratory and Mayer waves, from the 1/f fluctuation, which has been though to represent underlying fractal dynamics. Fractal structure was shown in the strange attractor with chaotic dynamics, which is thought to be a flexible and intelligent system. In this study, the coarse-graining spectral analyzing (CGSA) method was utilized to quantitatively evaluate the proportion of the 1/f fluctuation in the total power in the frequency domain and to analyze artificial circulation in the whole system. We implanted two pneumatically actuated ventricular assist devices as biventricular bypasses (BVBs) in chronic animal experiments using 4 healthy adult goats. To compare the natural and prosthetic circulation of each experimental animal, the BVB-type complete prosthetic circulation model with electrically induced ventricular fibrillation was adopted. All hemodynamic parameters of natural and prosthetic circulation were recorded under awake conditions and calculated with the use of a personal computer. With the use of the CGSA method, time-series data of the hemodynamics were analyzed and fractal percentages, extracting the 1/f fluctuation from a given time series, were calculated. Fractal percentages of the arterial blood pressure were 85.8 +/- 10.7% and 82.0 +/- 7.3% with natural and artificial circulation, respectively (not significant [NS]). 1/f fluctuation showed the characteristics of being fractal in a time series. The fractal structure showed robustness and error resistance in nonlinear dynamics. Therefore, our results suggest that the circulatory regulatory system of the artificial heart may have desirable characteristics such as error resistance.


Assuntos
Pressão Sanguínea/fisiologia , Coração Artificial , Coração Auxiliar/normas , Animais , Circulação Coronária/fisiologia , Eletrocardiografia , Análise de Fourier , Cabras , Circulação Pulmonar/fisiologia , Reprodutibilidade dos Testes
17.
Int J Artif Organs ; 19(5): 302-6, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8791151

RESUMO

To evaluate the automatic control algorithm of the total artificial heart (TAH) as an entity, and not just as parts, a non-linear mathematical analyzing technique including chaos theory was utilized. Chronic experiments on the biventricular bypass type artificial heart implantation were performed in healthy adult goats after the natural ventricles were removed. Hemodynamic time series data were recorded under the awake standing condition with TAH 1/R and fixed driving. Time series data were recorded on a magnetic tape and analyzed on a personal computer system with an A-D converter. Using the nonlinear mathematical technique, the time series data were embedded into the phase space and the Lyapunov numerical method was carried out for the quantitative evaluation of the sensitive dependence on the initial condition of the reconstructed attractor. Calculation of the largest Lyapunov exponents suggested that the reconstructed attractor of the left pump output during TAH 1/R control was a larger dimensional strange attractor, a characteristic pattern of deterministic chaos. A total system indicating chaotic dynamics was thought to be a flexible and intelligent control system. Thus, our results suggest that 1/R TAH control may be suitable for the biventricular assist type total artificial heart.


Assuntos
Coração Artificial , Coração Auxiliar/normas , Hemodinâmica/fisiologia , Algoritmos , Simulação por Computador , Humanos , Modelos Teóricos , Dinâmica não Linear
19.
Tokai J Exp Clin Med ; 20(4-6): 233-40, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8956466

RESUMO

We treated a 55-year-old male patient with Wegener's granulomatosis (WG) associated with frequent gastric bleeding from multiple ulcerative lesions. Only a few cases of frequent hemorrhaging of peptic ulcers associated with WG have been reported. In our case, a gastric biopsy showed mononuclear cell infiltration in the submucosal area, without granulomas or vasculitis. An endoscopic maneuver, as well as administration of immunosuppressive agents, combined with an H2 receptor antagonist and proton pump inhibitor successfully eliminated the gastrointestinal bleeding. In this case, proof that the gastrointestinal involvement was pathologically related to WG could not be demonstrated because neither granulomas nor vasculitis were observed in the insufficient biopsy specimen of the stomach. It is also possible that the uremic state and cytotoxic agents worsened the gastrointestinal involvement. However, immunosuppressive therapy combined with routine antiulcer treatment was very effective in repairing the ulcerative lesions. The gastrointestinal involvement was considered a possible complication of the WG.


Assuntos
Granulomatose com Poliangiite/complicações , Úlcera Gástrica/complicações , Gastroscopia , Hemorragia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Úlcera Gástrica/patologia , Úlcera Gástrica/terapia
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