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Biomedical subjects

K Yokoi

Publications and source records attributed to K Yokoi.

At least 127 records · Page 7Linked to original sources
PubMed1994

An experimental study of tracheal reconstruction using a freed piece of the right bronchus.

An experimental study of tracheal reconstruction using a separate piece of bronchus was performed in 6 dogs. After right upper lobectomy, a five-cartilage-ring length of the trachea extending from five cartilage rings above the carina was circumferentially resected; the right bronchus was transected just below the carina and above the second carina to provide the piece of bronchus, which was then interposed between the distal end of the upper trachea and the proximal end of the lower trachea by end-to-end anastomoses. One-stoma type carinal reconstruction (an anastomosis between the carina and the right intermediate bronchus) was performed. After completion of the airway reconstruction, the anastomotic site was wrapped with an omental flap. One dog died 14 days after operation due to anorexia and weakness, the necropsy in this dog revealed severe ischemic change of the interposed bronchus and ulcer formation at the stump of the upper bronchus. The other 5 dogs survived the operation. Bronchoscopically, the findings for the interposed free bronchus revealed severe ischemic change immediately after the operation, but almost normal findings were observed four to five weeks after the operation. The clinical relevance of this method of tracheal reconstruction is discussed.

Anastomosis, Surgical↗
PubMed1994

Penile verrucous carcinoma with anaplastic transformation following radiotherapy. A case report with human papillomavirus typing and flow cytometric DNA studies.

We report a case of penile verrucous carcinoma with anaplastic transformation after radiotherapy. A 49-year-old man with penile verrucous carcinoma initially underwent excision and chemotherapy followed by radiotherapy when the carcinoma recurred locally. Twenty-four months after the completion of radiotherapy, the verrucous cancer transformed to an anaplastic spindle-cell carcinoma, which resulted in his death 10 months after diagnosis. Autopsy confirmed a huge hemorrhagic recurrent lesion and lung metastases. In situ hybridization with biotinylated DNA probes did not detect any type of human papillomavirus (HPV) (types 6/11, 16/18, and 31/33/51) in either the primary or the anaplastic tumor. Immunohistochemical HPV capsid antigens were also negative in both lesions. A flow cytometric analysis, using paraffin-embedded materials, showed a diploid DNA content in the excised verrucous carcinoma and an aneuploid content in the anaplastic tumor. This patient most likely had radiation-induced transformation of an anaplastic carcinoma. Wide excision and, if necessary, amputation, are preferred to radiotherapy.

Carcinoma↗
PubMed1994

Familial occurrence of two patients with malignant rheumatoid arthritis.

In Japan, patients with rheumatoid arthritis associated with severe extra-articular manifestations due to vasculitis are diagnosed as having malignant rheumatoid arthritis. We report the occurrence of two cases of malignant rheumatoid arthritis in a Japanese family. Both patients, a father and son, expressed HLA-DR4 (Dw15), and were infected with Epstein-Barr virus. Moreover, the father developed malignant rheumatoid arthritis during reactivation of the Epstein-Barr virus. An unaffected male family member with the same HLA haplotypes was not infected by the virus. The possible role of the virus infection in the pathogenesis of malignant rheumatoid arthritis in a genetically susceptible family is discussed.

Adult↗
PubMed1994

Mediastinal lymph node metastasis from lung cancer: evaluation with Tl-201 SPECT--comparison with CT.

PURPOSE: To assess the usefulness of thallium-201 single photon emission computed tomography (SPECT) in detection of mediastinal lymph node metastasis from lung cancer. MATERIALS AND METHODS: Computed tomography (CT) and Tl-201 SPECT were performed in 113 patients with lung cancer. Surgical staging was performed in all patients, and the results of the two modalities were compared with the pathologic findings in 364 node stations. RESULTS: Cancerous nodes were found in 32.7% of the patients. The sensitivity of CT in detecting mediastinal node metastasis was 62%; specificity was 80%. These rates were higher for Tl-201 SPECT (76% and 92%, respectively). Furthermore, these rates were excellent in patients with enlarged mediastinal nodes at CT (87% and 93%, respectively). However, Tl-201 SPECT had more limited spatial resolution than did CT. CONCLUSION: Tl-201 SPECT is useful in evaluation of mediastinal node metastasis in lung cancer, especially for patients with enlarged nodes at CT.

Adult↗
PubMed1994

[An elderly patient with Takayasu's arteritis associated with antiphospholipid antibodies].

We report a patient with Takayasu's arteritis associated with antiphospholipid antibodies. An 84-year-old woman gradually developed gait and visual disturbances, dementia, myocardial infarction, and gangrene in all four limbs during a period of 8 years. Persistent inflammatory signs also continued for at least 8 years. Positive reaction for lupus anticoagulant by the diluted Russel viper venous time and positive reactions for cardiolipin antibodies were confirmed. However, she did not develop SLE. MR angiography revealed multiple and extensive occlusive changes in large vessels such as the aorta and its major branches. We believe antiphospholipid antibodies may have been related to severe occlusive vasculopathy in this patient.

Aged↗
PubMed1994

[Dose intensity in M-VAC chemotherapy with rG-CSF for metastatic transitional urothelial cancer].

The effect of M-VAC (methotrexate, vinblastine, adriamycin and cisplatin) chemotherapy supported recombinant human granulocyte stimulating factor (rG-CSF) was studied in 18 patients with metastatic urothelal cancer. The mean age of the patients was 66 years. Of the patients 6 had lung metastasis and 12 had distant lymph node metastasis. In this study recombinant human granulocyte stimulating factor was administered therapeutically at 100 to 250 micrograms subcutaneously after the white blood cell count was less than 3,000/mm. Relative dose-intensity (RDI) was 0.88 +/- 0.11 and 0.72 +/- 0.19 for 11 patients with rG-CSF and 7 without rG-CSF, respectively. The relative dose regardless of the interval of the cycle of M-VAC chemotherapy (%Dose) was 0.95 +/- 0.06 and 0.86 +/- 0.09 for the patients with rG-CSF and those without rG-CSF, respectively. Of seven patients without rG-CSF 3 patients responded (response rate 42%, mean survival period 7.4 months). Of 11 patients treated with rG-CSF 3 patients responded (response rate 72.7%, mean survival period 20.0 months). Although rG-CSF increased the RDI of M-VAC chemotherapy, the correlation of response with RDI was not clearly demonstrated. The therapeutical administrations of rG-CSF fail to improve the mean white blood cell nadir and to prevent the decrease of the platelet and reticulocyte count.

Aged↗
PubMed1994

Iron and zinc nutriture of premenopausal women: associations of diet with serum ferritin and plasma zinc disappearance and of serum ferritin with plasma zinc and plasma zinc disappearance.

The Second National Health and Nutrition Examination Survey found low iron and zinc intakes and low serum ferritin in many premenopausal women. Therefore food frequency history, serum ferritin, plasma zinc, plasma zinc disappearance, and zinc turnover rate were measured in healthy premenopausal women. Plasma zinc disappearance and turnover rate were determined by inductively coupled plasma mass spectroscopic analysis of the plasma ratio of zinc 67 to zinc 68 before and 30 to 60 minutes after intravenous injection of 67Zn. Food frequency predicted serum ferritin concentration in 38 women and plasma zinc disappearance in 19. Frequent red meat intake was associated with higher serum ferritin concentration and a "normal" plasma zinc disappearance. Frequent milk intake was associated with lower serum ferritin concentration and a rapid plasma zinc disappearance. After exclusion of an outlier, in 18 women serum ferritin concentrations were lower when plasma zinc was < 70 micrograms/dl (p < 0.03), and plasma zinc disappearance and turnover rate were higher when serum ferritin was < 20 ng/ml (p < 0.05). Serum ferritin concentration and plasma zinc disappearance constant were inversely and nonlinearly related (R2 = 0.777, p = 0.0003). These findings suggest that avoidance of red meat increases the risk of iron and zinc deficiencies, and low serum ferritin concentrations suggest the possibility of low zinc nutriture.

Adult↗
PubMed1993

A gel filtration high-performance liquid chromatographic method for determination of hepatic and renal metallothionein of rat and in comparison with the cadmium-saturation method.

Metallothionein (MT) is a low-mol-wt protein. The essential trace elements copper and zinc and the potentially toxic elements, such as cadmium, can induce the synthesis of and bind to MT. The major functions of MT are related to metal metabolism. This paper reported and evaluated a new method for determination of hepatic and renal MT of rat by using high performance liquid chromatography (HPLC) with a Superdex 75 gel filtration column. The tissue was homogenized and centrifuged, then the supernatant was pretreated simply by cadmium saturation and heating before HPLC determination. The MT was completely and clearly separated from other proteins in the rat tissues in a short time, and was quantitated directly as a function of UV absorbance at 250 nm. The recovery both for hepatic and renal MT of rat were exceed 90%. The coefficient of variation was 1.3% for hepatic MT of rat and 1.7% for renal MT of rat. The detection limit was 0.265 microgram for hepatic MT and 0.095 microgram for renal MT of rat. The present method was compared with the traditional cadmium-saturation method for determination of hepatic and renal MT of rat. A good correlation was found in these two methods.

Animals↗
PubMed1993

[Mitochondrial myopathy with autosomal dominant inheritance--report of a family and review of the literature].

We report a family of mitochondrial myopathy which appeared to be interited as an autosomal dominant trait. The proband is a 58-year-old Japanese male, who presented with bilateral ptosis, chronic progressive ophthalmopletia, dysphagia, and atrophy of proximal muscles in the upper extremities. There was no cataract or retinal degeneration. Serum creatine kinase (CK) and lactic acid levels were normal. Cardiac evaluations were normal. Muscle biopsy revealed 7% of ragged red fibers. Cytochrome c oxidase activity in the muscle was decreased to 50% of the control value. PCR analysis of muscle mitochondrial DNA revealed 3 large-scale deletions in the non-D-loop regions, ranging in size from 4.2 kb to 5.2 kb. His father, three siblings, and the two children had symptoms similar to the proband. We have reviewed forty-five individuals from six families, including our family, who had mitochondrial myopathy with autosomal dominant inheritance. Frequent manifestations include chronic progressive ophtalmoplegia (91.2%), ptosis (95.6%), hearing loss (72.7%), dysphagia (60.0%), limb weakness (74.1%), and respiratory muscle weakness (75.0%). Interestingly, there is no individual with retinal degeneration or cardiac involvement. Serum CK and lactic acid levels may be elevated. CT of the head is normal. Muscle biopsy shows ragged red fibers and the frequency of cytochrome c oxidase-negative fibers ranges from 0 to 38%. Multiple large-scale deletions of mitochondrial DNA, ranging in size from 4.2 to 8.3 kb, are found in the muscle, all of which are located in the non-D-loop region of the mitochondrial DNA. The multiplicity of deletions may be one to the characteristic features of this form of mitochondrial myopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[A case of squamous cell carcinoma of the trachea in a female cigarette smoker].

A rare case of squamous cell carcinoma of the trachea in a female cigarette smoker is reported. The patient was a 72-year-old female with smoking index of 440 who developed wheezing and dyspnea on December 18, 1991. She was diagnosed as having bronchial asthma and hospitalized, but the symptoms were not improved. Bronchofiberscopic examination was performed and revealed a tracheal tumor on April 24, 1992. She was then referred to this cancer center. CT scan of the neck on admission showed a solid tumor which was 19 x 18 mm in diameter and protruded from the membranous portion and the right side of the tracheal wall into the lumen. Bronchofiberscopic findings revealed a soft polypoid tumor with a whitish coat on the surface and a tendency to bleed, at the second tracheal ring from the vocal cord. Histological findings of the biopsied specimen were compatible with poorly differentiated squamous cell carcinoma. A segmental resection of the trachea with end-to-end anastomosis was performed on May 6th, 1992. Postoperative radiation therapy (50.4 Gy) was added because of the residual microscopic cancer in the distal membranous portion of the tracheal wall. Female cases of squamous cell carcinoma of the trachea have been rarely reported in Japan. The relationship between squamous cell carcinoma of the trachea and smoking is considered.

Aged↗
PubMed1993

A study of pharyngeal symptoms caused by bronchofiberscopy.

We investigated the occurrence of pharyngeal symptoms in 100 patients who had undergone bronchofiberscopies by conducting a post-examination survey of the patients. Eighty-four patients complained of having a problem. Seventy-five patients, including 26 with dysphagia, complained of pharyngeal symptoms. The proportion with pharyngeal symptoms whose symptoms appeared on the day of examination was a high 89.4%. In 70.6% of cases, the duration of symptoms was less than four days. The pharyngeal symptoms were particularly common among patients who had undergone a bronchofiberscopy on a previous occasion or whose examination lasted for 15 min or more. A greater dysphagia incidence was noted among patients who had required an endotracheal tube (P = 0.03) and among those whose examination had lasted for 15 min or more (P = 0.01). Based on the results, we are now studying methods of alleviating pharyngeal symptoms, including dysphagia.

Adult↗
PubMed1993

[The use of the reverse latissimus dorsi muscle flap in the management of bronchopleural fistula].

The management of a postoperative bronchopleural fistula remains a major challenge for the thoracic surgeon. We present a series of three patients who underwent closure of the fistulas with the distal flap of the divided latissimus dorsi muscle (the reverse latissimus dorsi muscle flap) and a limited thoracoplasty. The primary resections, which were performed through a standard posterolateral thoracotomy, were right lower lobectomy in two patients and right middle and lower bilobectomy in the other. The initial myoplasty produced prompt fistula closure in 2 patients and failed in the other patient because of a large empyema space. The reverse latissimus dorsi muscle flap could be used for the management of bronchopleural fistula in selected patients who underwent lower lobectomy or middle and lower bilobectomy.

Aged↗