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Biomedical subjects

J Yoshida

Publications and source records attributed to J Yoshida.

At least 145 records · Page 8Linked to original sources
PubMed1999

Evaluation of NOx in the cardiovascular system: relationship to NO-related compounds in vivo.

Diverse attention should be paid to evaluating NOx (NO2- and NO3-) in plasma as an index of endothelial nitric oxide (NO) formation in vivo. Nitric oxide, which subsequently appears as NOx, originates from different types of NO synthase and from nonenzymatic reactions. NOx also comes from exogenous sources such as food and gastrointestinal microorganisms. The fate of the NO incorporated into activation of guanylate cyclase, formation of nitrosyl hemoglobin (or nitrosohemoglobin), nitrosothiols, peroxynitrite and its derivatives and other possible compounds is not clear at present. However, some of these compounds would produce NOx as by-products or as final products through metabolism. Therefore, plasma NOx contains information about these pathways, although how extensively these factors contribute to plasma NOx has not been quantitatively defined. A theoretical simulation of NOx in the systemic circulation indicates that only small changes are expected by inhibition or stimulation of endothelial NO production. Measuring NOx production during coronary circulation has the advantage that some degree of NOx accumulation is expected from intact endothelial cells because an excretion system is absent in the heart.

Animals↗
PubMed1999

[Autoimmune fatigue syndrome and fibromyalgia syndrome].

We have encounted two patients with fibromyalgia (FM) initially diagnosed as having autoimmune fatigue syndrome (AIFS). To investigate the relationship between AIFS and FM, the distribution of the tender points in patients with AIFS was assessed according to the ACR criteria for FM. It was revealed that AIFS patients had 5.6 tender points on averages. Patients with headaches, digestive problems, or difficulty going to school had more tender points than patients without. Patients with ANA titers < 1: 160 had more tender points than patients with ANA > or = 1: 160. Anti-Sa negative patients had more tender points than positive patients. These results suggest a relationship between AIFS and FM in terms of the pathophysiologic mechanisms of the numerous tender points. In other words, ANA-positive FM patients could be one form of AIFS, as well as ANA-positive chronic fatigue syndrome patients. Thus, autoimmunity could explain the controversial disease entities of FM and/or CFS.

Adolescent↗
PubMed1999

Video-assisted thoracoscopic surgery for small indeterminate pulmonary nodules: indications for preoperative marking.

STUDY OBJECTIVE: To determine the indications for preoperative localization of a small indeterminate pulmonary nodule. DESIGN: In this retrospective study, univariate and multivariate analyses were performed by the logistic regression procedure. SETTING: A single National Cancer Center Hospital in Japan. PATIENTS: A series of 92 consecutive patients who underwent video-assisted thoracoscopic surgery (VATS) at our institute between 1993 and 1996. INTERVENTIONS: The frequency and reasons for conversion to thoracotomy were assessed retrospectively. All preoperative CT scans were reviewed for eight radiologic features by two of the authors. These data were entered into univariate and multivariate analyses to identify the significant risk factors for a failure to detect a pulmonary nodule. MEASUREMENTS AND RESULTS: Fifty patients (54%) needed conversion to a thoracotomy. The most common reason for the conversion was failure to localize nodules (46%). Univariate and multivariate analyses of 11 variables revealed one significant risk factor in the failure to detect nodules: distance to the nearest pleural surface (p < 0.05). Tumor size on radiograph remained marginally significant (p = 0.065) in multivariate analyses. If the distance to the pleural surface was > 5 mm in cases of nodules < or = 10 mm in size, the probability of failure to detect a nodule was 63%. CONCLUSIONS: Our results suggested the indications for preoperative localization of a peripheral pulmonary nodule. Preoperative marking for a small indeterminate pulmonary nodule should be considered when the distance to the nearest pleural surface is > 5 mm in cases of lung nodules of < or = 10 mm in size.

Adolescent↗
PubMed1999

Preoperative short-term administration of octreotide for facilitating transsphenoidal removal of invasive growth hormone-secreting macroadenomas.

The somatostatin analog octreotide was administered prior to transsphenoidal surgery in three patients with tumors that extended to the suprasellar space and one side of the cavernous sinus. Octreotide, 100 micrograms twice a day, was subcutaneously injected for 2 weeks. Octreotide administration reduced the serum growth hormone (GH) levels in these patients from 82 to 22 ng/ml, from 148 to 12 ng/ml, and from 129 to 9 ng/ml. The tumor size shrank by about 50%, and the suprasellar extension disappeared in two patients. The main tumor was sharply dissected from the normal pituitary gland at surgery. Intracavernous portions were removed using a curette. Postoperatively, GH levels were less than 5 ng/ml in two patients, and 8.5 ng/ml in one patient. Follow-up magnetic resonance imaging revealed a small residual tumor in one side of the cavernous sinus in all patients. Follow-up GH levels were less than 5 ng/ml in one patient, and less than 2 ng/ml in two patients treated with bromocriptine. Preoperative administration of octreotide for 2 weeks reduced tumor volume and allowed near-total surgical resection of invasive macroadenomas without compromising the treatment course. Residual tumor due to intracavernous extension can be managed with bromocriptine or gamma knife radiosurgery.

Acromegaly↗
PubMed1999

The relationship between magnetic resonance imaging findings and clinical manifestations of hypothalamic hamartoma.

OBJECT: Hypothalamic hamartoma is generally diagnosed based on its magnetic resonance (MR) imaging characteristics and the patient's clinical symptoms, but the relationship between the neuroradiological findings and clinical presentation has never been fully investigated. In this retrospective study the authors sought to determine this relationship. METHODS: The authors classified 11 cases of hypothalamic hamartoma into two categories based on the MR findings. Seven cases were the "parahypothalamic type," in which the hamartoma is only attached to the floor of the third ventricle or suspended from the floor by a peduncle. Four cases were the "intrahypothalamic type," in which the hamartoma involved or was enveloped by the hypothalamus and the tumor distorted the third ventricle. Six patients with the parahypothalamic type exhibited precocious puberty, which was controlled by a luteinizing hormone-releasing hormone analog, and one patient was asymptomatic. No seizures or mental retardation were observed in this group. All patients with the intrahypothalamic type had medically intractable seizures, and precocious puberty was seen in one. Severe mental retardation and behavioral disorders including aggressiveness were seen in two patients. The seizures were controlled in only one patient, in whom stereotactically targeted irradiation of the lesion was performed. This topology/symptom relationship was reconfirmed in a review of 61 reported cases of hamartoma, in which the MR findings were clearly described. The parahypothalamic type is generally associated with precocious puberty but is unaccompanied by seizures or developmental delay, whereas the intrahypothalamic type is generally associated with seizures. Two thirds of patients with the latter experience developmental delays, and half also exhibit precocious puberty. CONCLUSIONS: Classification of hypothalamic hamartomas into these two categories based on MR findings resulted in a clear correlation between symptoms and the subsequent clinical course.

Adolescent↗
PubMed1999

Immunohistochemical staining of DNA topoisomerase IIalpha in human gliomas.

OBJECT: The enzyme DNA topoisomerase IIalpha (Topo IIalpha) was tested as a measure of cell proliferation in gliomas. METHODS: Immunostaining for the Topo IIalpha and for the Ki-67 antigen (MIB-1 antibody) was performed in paraffin-embedded tissue sections obtained from 25 resected human gliomas. Additionally, cultured human glioma cells were subjected to simultaneous flow cytometry to determine Topo IIalpha and DNA content. Using flow cytometric analysis, the authors found that the Topo IIalpha antibody labeled cells in the S, G2, and M phases of the cell cycle and also those in some parts of the G0 and G1 phases. In histological sections, Topo IIalpha showed more distinct staining than MIB-1, particularly in older archival cases. The proliferative indices (PIs) based on cells staining for MIB-1 and Topo IIalpha correlated highly with one another (r = 0.96). The Topo IIalpha PI immunopositivity was seen in 4.07% of cells in the low-grade astrocytoma group, 11.97% in the anaplastic astrocytoma group, and 13.84% in the glioblastoma multiforme group, representing significant differences between low-grade astrocytoma and both anaplastic astrocytoma and glioblastoma. A Topo IIalpha PI less than 5% predicted longer patient survival (p = 0.003). CONCLUSIONS: Immunostaining for Topo IIalpha represents a useful alternative to MIB-1 as a proliferative index in human gliomas.

Adolescent↗
PubMed1999

[Nephrostomy of which catheter can be introduced from the abdominal wall].

AIM OF STUDY: The aim of this study is to find out the method for the nephrostomy of which catheter can be introduced from the abdominal wall. METHODS: Subjects were the 7 patients whose agreement for this new method could be obtained. After the general nephrostomy was performed, 3 cm skin incision to the outer portion of nephrostomy, as well as 5 mm skin incision to the abdominal wall were added, and the subcutaneous tunnel between the both skin incisions was made using the special tunneler. A guide wire was introduced into the renal pelvis through the subcutaneous tunnel, and then 14 F Maleocot catheter was introduced from the abdominal skin incision to the renal pelvis. At the skin incision of the nephrostomy, catheter and subcutaneous tissue were fixed using 3-0 cutgut suture to prevent the outcomming of the catheter. RESULTS: In case 1 to case 4 showed some trouble, but case 5 to 7 showed no trouble. The operation time and the extent of invasion of our method were as well as that of the general nephrostomy, but the managements by the patients were as simple as that of the ureterocutaneostomy. CONCLUSION: The quality of our patients seem to close to that of uretero-cutaneostomy. And for the patients who have hydronephrosis after several type of urinary diversions, our method should be recommendable than the general nephrostomy.

Abdominal Muscles↗
PubMed1999

[A patient operated for occlusion of the superior mesenteric artery].

A 40-year-old woman presented with fever, dysarthria, and left hemiparesis. Diagnostic imaging detected an infarction in the right cerebrum; lupus anticoagulant was positive. A T4N3M0 adenocarcinoma coexisted in the left lung, which was irradiated once. Two days later, the superior mesenteric artery was occluded. The bowel was widely resected but she died of hepatic infarction. The lung cancer may have triggered catastrophic antiphospholipid syndrome.

Adenocarcinoma↗
PubMed1999

Association of angiotensin-converting enzyme gene polymorphism and renal pathology in Japanese children with IgA nephropathy.

Polymorphism of the gene that codes for angiotensin I-converting enzyme (ACE) is associated with increased severity of immunoglobulin A (IgA) nephropathy in adult patients. We evaluated the relationship between the polymorphism of ACE genotypes and the pathological and clinical findings in Japanese children with IgA nephropathy. Patients with moderate/diffuse mesangial proliferation, glomerular sclerosis and tubulointerstitial damage showed a significant increase of the D/D type compared to those who had mild/focal mesangial proliferation, without glomerular sclerosis or tubulointerstitial damage (p < 0.05). Proteinuria at the first renal biopsy was significantly higher in the former group compared with the latter group except glomerular sclerosis (p < 0.01). IgA nephropathy patients with tubulointerstitial damage also showed an increased serum creatinine level compared to patients without the damage (p < 0.03). We conclude that ACE gene polymorphism may be correlated with the prognosis of IgA nephropathy in Japanese children.

Biopsy↗
PubMed1999

[Bronchocutaneous fistula after treatment for breast cancer: a case report].

We describe a case of bronchocutaneous fistula that developed after surgery and radiotherapy for breast cancer. A 69-year-old woman presented with fever and the leakage, on expiration, of bubbles from a site on the left chest wall where a Halsted mastectomy and radiotherapy (60 Gy) had been performed 19 years earlier. Computed tomography and magnetic resonance imaging revealed a fistula bridging a bronchus and the skin. Repeated biopsies of the fistula failed to disclose any malignancy. The fistula closed after treatment with antibiotics, and has remained closed for 9 months, as disclosed by identical tomographic images. The paucity of literature describing the diagnostic imaging of bronchocutaneous fistula prompted this report.

Aged↗
PubMed1998

DNA ploidy, proliferative activities, and immunophenotype of malignant lymphoma: application of flow cytometry.

BACKGROUND: To explore the flow cytometric diagnosis of malignant lymphoma, we examined the deoxyribonucleic acid (DNA) ploidy, proliferative activities, and immunophenotype of surgical biopsy- and fine-needle aspiration (FNA)-derived materials. Our goal was to determine the possibility of making a diagnosis of malignant lymphoma by flow cytometric analysis of FNA-derived materials. METHODS: The DNA ploidy and proliferative indices including the percentage of S-phase fraction (SPF), G2 + M fraction (G2M), and Ki-67-positive fraction (Ki-67) were analyzed on the fresh materials from 84 consecutive patients with suspected malignant lymphoma. Flow cytometric analysis of surface antigens was simultaneously performed. Fourteen of the patients underwent FNA and subsequent surgical biopsy of the same lymph nodes for flow cytometric analysis. RESULTS: The proliferative indices of intermediate-grade non-Hodgkin's lymphomas (NHL) (n = 28) and high-grade NHL (n = 23) were significantly higher than those of the reactive hyperplasia (n = 25). The total for SPF + G2M of 6% was a satisfactory threshold for differentiating these NHL from reactive hyperplasia (sensitivity of 84%, specificity of 88%, and accuracy of 86%). However, low-grade NHL (n = 3) and Hodgkin's lymphoma (HL, n = 5) could not be discriminated by employing this parameter. DNA aneuploidy was seen in 13 of the 28 intermediate-grade NHL and 8 of the 23 high-grade NHL, whereas it was not seen in 25 reactive hyperplasia, 3 low-grade NHL, and 5 HL. The percentage of CD19-positive cells in B-cell NHL or CD3-positive cells in T-cell NHL was significantly higher compared with those for reactive hyperplasia. The percentage of CD16 + CD56-positive cells in natural killer (NK) cell NHL was extremely high, with a mean of 91.8%. Flow cytometric results for FNA-derived materials showed excellent correlation with those for surgical biopsy-derived specimens. CONCLUSIONS: Analyses of DNA ploidy, proliferative activities, and immunophenotype by flow cytometry (FCM) are useful for diagnosing intermediate- and high-grade NHL. Fine-needle aspiration is a less invasive approach than surgical biopsy, and, when combined with FCM, it may have a place in the diagnosis of NHL.

Biopsy, Needle↗
PubMed1998

Hemifacial spasm associated with Marfan's syndrome: a case report.

The authors describe a case of hemifacial spasm associated with Marfan's syndrome. A 24-year-old-woman suffered from left hemifacial spasm for 6 years. She had undergone surgical treatments for bilateral ectopia lentis and kyphoscoliosis in the second decade of life. She also had unusually long and slim limbs with arachnodactyly. Three-dimensional CT angiography revealed bilateral tortuous and elongated vertebral arteries. Microvascular decompression was performed following a left lateral suboccipital craniotomy. The root exit zone of the left seventh nerve was directly compressed by the proximal segment of the anterior inferior cerebellar artery (AICA) and the left vertebral artery. These arteries were decompressed with pieces of Teflon cotton. The patient's symptoms completely resolved following surgery. We review cerebrovascular disorders in Marfan's syndrome and discuss the pathogenesis and possible mechanisms of vascular compression in these patients.

Adult↗
PubMed1998

Video-enhanced microscopic visualization of apoptotic cell death caused by anti-Fas antibody in living human glioma cells.

To study the morphological changes of anti-Fas antibody-mediated apoptosis in living U251-SP human glioma cells, we employed video-enhanced contrast differential interference contrast (VEC-DIC) microscopy. In our previous study, we investigated the susceptibility of human glioma cell lines to anti-Fas Immunoglobulin M (IgM) antibody. U251-SP cells express Fas antigen on their surface. The cells exposed to anti-Fas antibody underwent apoptotic cell death, as reported previously. In this study, morphological changes of apoptosis characterized by bleb formation, shrinkage of cells, and nuclear condensation were observed under VEC-DIC microscopy in U251-SP human glioma cells treated with anti-Fas antibody. These results demonstrate the usefulness of VEC-DIC microscopy to study the process of apoptotic cell death.

Antibodies↗
PubMed1998

Pneumothorax due to hemangiopericytoma metastasis from the thigh.

A 25-year-old female had malignant hemangiopericytoma of the right thigh resected. Three years later, right pneumothorax developed, necessitating a thoracotomy. A 3-cm bulla was discovered on the lower right pulmonary lobe and was subsequently resected. Microscopy showed tumor cells which were positive for actin, but negative for epithelial membrane antigen, vimentin, and factor VIII-related antigen--features compatible with those of the thigh. The patient has been free of the disease for five years. Pertinent literature reveals similar cases with hemangioendothelioma but offers few reports on pneumothorax caused by metastatic hemangiopericytoma.

Adult↗
PubMed1998

Effect of human interferon beta gene transfer upon human glioma, transplanted into nude mouse brain, involves induced natural killer cells.

We investigated the immunological responses induced by human interferon beta (IFNbeta) gene transfer in human gliomas produced in the brains of nude mice. A suspension of human glioma U251-SP cells was injected into the brains of nude mice. The IFNbeta gene was transferred by intratumoral injection with cationic liposomes or cationic liposomes associated with anti-glioma monoclonal antibody (immunoliposomes). When intratumoral injection of liposomes or immunoliposomes containing the human IFNbeta gene was performed every second day for a total of six injections, starting 7 days after tumor transplantation, complete disappearance of the tumor was observed in six of seven mice that had received liposomes and in all seven mice receiving immunoliposomes. In addition, experimental gliomas injected with immunoliposomes were much smaller than those injected with ordinary liposomes following delayed injections beginning 14 days after transplantation. An immunohistochemical study of the treated nude mouse brains revealed a remarkable induction of natural killer (NK) cells expressing asialoGM1 antigen. To investigate the significance of NK cells in the antitumor effect, we injected liposomes or immunoliposomes containing the human IFNbeta gene into tumors in nude mice depleted of NK cells by irradiation and anti-asialoGM1 antibody administration. The antitumor effect of the liposomes or immunoliposomes was abolished. Subsequent subcutaneous glioma challenge of the nude mice after intracerebral tumor implantation and gene transfer resulted in no subcutaneous tumor growth. These results suggest that the induction of NK cells is important in the cytocidal effect of liposomes or immunoliposomes containing the human IFNbeta gene upon experimental gliomas.

Animals↗