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Biomedical subjects

M Sakamoto

Publications and source records attributed to M Sakamoto.

At least 235 records · Page 13Linked to original sources

[Clinical evaluation of lung abscess diagnosed by transtracheal aspiration].

We have diagnosed lung abscess according to findings of infiltration with cavity formation on chest X-ray and/or CT-scan and pathogens isolated from transtracheal aspirates. We evaluated the clinical features of 20 patients with lung abscess (18 males and 2 females, mean age; 54.3 years). Diabetus mellitus and periodontal diseases were prominent underlying diseases in patients with lung abscess. Cough was complained in 13 patients, chest or back pain in 9, purulent sputum in 8 and hemosputum in 5 when the patients admitted to our hospital. A temperature higher than 38 degrees C was present in 12 patients but temperature les than 37 degrees C in 2. Multiple microorganisms were cultured from TTA in 15 patients. A mean of 2.7 bacterial species per patient was isolated, aerobes alone being isolated in 2 patients, anaerobes alone in 3, and mixed aerobic and anaerobic isolates in 10. Seventeen strains of aerobes and 35 of anaerobes were isolated. Major pathogens were Streptococcus pneumoniae, Streptococcus intermedius and other in aerobes, and Peptostreptococcus micros, Fusobacterium necrophorum, Prevotella melaninogenica and others in anaerobes. Abnormality of chest X-ray was located on the right upper lobe in 6 patients, the right lower lobe in 6, the left upper lobe in 6, the left lower lobe in 4 and the right middle lobe in 1. All patients were cured only by treatment of antimicrobial agents, but cavity formation on chest X-ray remained in 4 patients after the treatment.

Adult↗

[A case of imported paratyphoid fever associated with Giardia lamblia and Isospora belli infection].

We report a case of imported paratyphoid fever associated with Giardia lamblia and Isospora belli infection. The patient was a 23-year-old Japanese female with complaints of high grade fever and diarrhea after 10 days traveling to Nepal. Salmonella Paratyphi A was isolated from the blood and fecal cultures on admission and Ciprofloxacin of 200 mg tid was administered for 14 days. Fecal examination revealed cysts of G. lamblia at the same time and metronidazole of 250 mg tid for 7 days was effective for their eradication. During the follow-up studies oocysts of I. belli were found and cotrimoxazole of 960 mg bid for 10 days was effective for their eradication. Fecal examinations on parasites which is rare in Japan such as I. belli are recommended to the cases returning from tropical areas.

Adult↗

[Bacillus cereus septicemia in a patient with severe aplastic anemia].

A 78-year-old female was admitted with complaints of malaise and fatigue in the legs. The patient was diagnosed as severe aplastic anemia and treatment was started with metenolone and steroid pulse therapy. Administration of antibiotics and granulocyte-colony stimulating factor which led to a resolution of the high fever. About four months after admission, the patient developed vomiting and abdominal pain with a spiking fever. The next day after suddenly losing consciousness, she died. B. cereus was isolated from blood cultures. Autopsy specimens of the liver, cardiac muscle and lung showed changes due to B. cereus. This pathogen is widely distributed in nature. We should not overlook B. cereus as a contamination, but rather should consider it a potential pathogen in immunocompromised hosts, when it is isolated from blood cultures.

Aged↗

[A case of AIDS complicated with isosporiosis as initial manifestation].

We reported a Thailander patient with isosporiasis accompanied by AIDS. The 34-year-old male, who had been living in Japan for six years, was admitted to our hospital complaining of diarrhea and body weight loss. After admission the patient developed acute renal failure due to dehydration resulting from diarrhea. Laboratory findings on admission showed neither significant microorganisms nor parasite ova in the stool. The patients was given both an intestinal drug and an antibacterial agent, but is vain. Frequent stool examinations disclosed Isospora oocyst in the feaces. Co-trimoxazole was administered resulting in remarkable diarrheal improvement. Renal function was also improved without dialysis. Although isosporiasis is rarely found in Japan, it is stressed that in the AIDS patient with persistent diarrhea who may develop a parasitic disease as did in this case, frequent fecal examinations should be conducted.

AIDS-Related Opportunistic Infections↗

[Clinical analysis of patients with sepsis--comparison between underlying diseases].

We evaluated the clinical data in 83 patients with sepsis, which was diagnosed by both Bone's definition of sepsis and positive isolates from blood culture, according to their underlying diseases. This study enrolled a total of 117 septic episodes in 83 patients (57 males and 26 females, mean age: 52.0 years). We classified 3 groups, including hematological malignancies (46 patients, 72 episodes), solid malignant tumors (23 patients, 25 episodes) and non-malignancies (14 patients, 20 episodes), by the underlying diseases. Of the total number of isolates from blood culture, 53.0% were single gram-positive bacteria, 33.3% were single gram-negative bacteria, 7.7% were single fungus and 6.0% were polymicrobial organisms. In addition, coagulase negative staphylococci was isolated most often in patients with hematological malignancies. Sepsis was often caused by infectious focuses of hemorrhoid, stomatitis or intravenous catheter in patients with hematological malignancies, by pneumonia in patients with solid malignant tumors and by urinary tract infection in patients with non-malignancies. Mortality of sepsis in patients with solid malignant tumors (48%) was highest in 3 groups. Septic patients, who were complicated with shock and/or DIC, has poor prognosis in all groups. Serum albumin level was significantly lower in dead patients than patients who survived. These results suggest that clinical features may be different according to the underlying diseases of patients with sepsis.

Aged↗

[A clinical investigation of bacteremia for the past ten years at the Second Department of Internal Medicine, Jikei University Hospital].

We clinically investigated a total of 288 cases of bacteremia for the past ten years, from January 1986 to December 1995, at the Second Department of Internal Medicine in the jikei University Hospital. All of the subjects who had a positive reaction to blood culture or catheter tip culture were investigated for their basic disease, complications, and detected bacteria. Malignant tumors, chronic renal failure, diabetes mellitus, and hematologic disease were frequent by noted. The cases due to primary infection were mainly respiratory organ infection or urinary tract infection, which were 47.8% of the total. In 31.3% of the total, catheter tip cultures were positive. Except for catheter related infection, Gram-positive coccus were detected in 40.3%, which was most frequent. Methicillin resistant Staphylococcus aureus (MRSA) were 8.1% and Staphylococcus epidermidis were 11.2%. In catheter related infection, Gram-positive coccus were detected in 59.9%, which was most frequent amongst them, MRSA was 17.2%, S. epidermidis was 16.2%. The mortality of bacteremia was 12.5%, mainly from hematologic diseases, immunodeficiency due to long term steroid administration etc. Accordingly, the more the advance of chemotherapy, the better the prognosis of septicemia is. Appearance of catheter related infection was unexpected frequent. Increase of immunocompromised host is thought to be one of the main factors in the outbreak of bacteremia.

Adolescent↗

Bronchial hyperresponsiveness, hypersensitivity to analgesics and urinary leukotriene E4 excretion in patients with aspirin-intolerant asthma.

This study was designed to investigate the protective effect of cromolyn sodium on airway sensitivity to sulpyrine, and bronchial responsiveness to methacholine, and to investigate whether this protective activity is associated with reduction in aspirin-induced excretion of urinary leukotriene E4 (u-LTE4), a marker of the cysteinyl LT overproduction that participates in the pathogenesis of aspirin-induced asthma. We assessed the effects of pretreatment with cromolyn sodium on bronchoconstriction precipitated by inhalation of methacholine and sulpyrine in 16 adult patients with mild or moderate aspirin-intolerant asthma; those who were in stable clinical condition and were hypersensitive to a sulpyrine provocation test were included in this study. A double-blind, randomized, crossover design was used. u-LTE4 was measured using combined reverse-phase high-performance liquid chromatography enzyme immunoassay. Cromolyn sodium protected against analgesic-induced bronchoconstriction through mechanisms that are not related to its bronchodilator property, but to the improvement of both bronchial hyperresponsiveness and hypersensitivity to analgesics (p<0.01 and p<0.001). Although excretion of u-LTE4 did not increase after the methacholine provocation test, it significantly increased after sulpyrine provocation (p<0.01). Furthermore, after pretreatment with cromolyn sodium, the maximum level of u-LTE4 after the sulpyrine provocation test was significantly lower than in controls (p<0.01). These results support the hypothesis that cysteinyl LT is one of the most important components in the pathogenesis of aspirin-intolerant asthma. Cromolyn sodium improves both hypersensitivity to analgesics, and bronchial hyperresponsiveness in aspirin-intolerant asthma.

Adult↗

Eight-year follow-up study of a patient with central alveolar hypoventilation treated with diaphragm pacing.

We had treated a 17-year-old girl with central alveolar hypoventilation with diaphragm pacing at home for the past 8 years. Nocturnal diaphragm pacing with an open tracheostomy was effective in maintaining an adequate ventilation after 4 months of undergoing training of the diaphragm on the pacemaker implantation. However, the diaphragm pacemaker failed to maintain it mostly in the presence of respiratory tract infection, when she was treated with intermittent positive-pressure ventilation. Pulse oximetry was used at home for monitoring the adequacy of respiratory support. We conclude that the respiratory assistance by the diaphragm pacemaker or the use of a mechanical ventilator as a backup was highly useful for the home care of a patient with central alveolar hypoventilation.

Adolescent↗

Combination chemotherapy with G-CSF, M-CSF and EPO: successful treatment for acute myelogenous leukemia without blood transfusion at lower medical costs.

A 55-year-old Jehova's Witness was treated for acute myelogenous leukemia (AML) by intensive chemotherapy with enocitabine, 6-mercaptopurine and daunorubicin. G-CSF, M-CSF and EPO were subsequently administered. Even though no blood transfusion was given for religious reasons, complete remission was achieved without serious infection and hemorrhage. The total cost for induction chemotherapy was less expensive than is the case for elderly AML patients. This case indicates that the administration of cytokines might reduce the incidence of infection and the necessity for blood products, which would result in favorable cost effectiveness for the treatment of elderly patients with AML.

Antineoplastic Combined Chemotherapy Protocols↗

Determination of serum physiological concentration of methylmalonic acid by gas chromatography-mass spectrometry with selected ion monitoring.

We developed a sensitive assay for the rapid determination of serum methylmalonic acid concentration using capillary gas chromatography-mass spectrometry (GC/MS) with selected ion monitoring and a simple solid-phase extraction. The assay was linear up to 10,000 nmol/L and had a detection limit < 50 nmol/L, average recovery of 98% and between-day coefficient of variation at concentrations of 570 and 2206 nmol/L of 7.7% and 5.4%, respectively (n = 25). Comparison with another validated GC/MS method using sera with a wide range of methylmalonic acid concentrations (94-2020 nmol/L) revealed a slope and intercept of 0.97 and 17 nmol/L, respectively (n = 38). Methylmalonic acid concentrations determined by this assay in a group of apparently healthy individuals ranged from 64-331 nmol/L (n = 81). We conclude that the method is ideally suited for the determination of methylmalonic acid at physiological concentrations in both clinical and research laboratories.

Biological Assay↗

Alpha 2-adrenoceptor-mediated antisecretory effect of hypoxia in conscious rats.

Gastric acid secretion is suppressed, resulting in a significant rise in gastric pH, when conscious rats are exposed to hypoxia (Yamaji et al., 1996). When adrenal medullectomized rats were exposed to moderate (10.5% O2) hypoxia for 3 h, gastric acid secretion was restored to nearly the level in normoxia by the adrenal medullectomy. In severe (7.6% O2) hypoxia, the operation also caused an increase in the level of gastric acid output, although the extent was lower than that under 10.5% O2 hypoxic conditions. Gastric pH was normalized by the operation even with 7.6% O2 hypoxia. Similar results were obtained when reserpine, which causes an adrenergic discharge, was administered. When an alpha 2-adrenoceptor blocking agent, yohimbine, was administered, the inhibitory effect of 10.5% and 7.6% O2 hypoxia on gastric acid secretion was almost completely removed. However, neither prazosin (an alpha 1-adrenoceptor blocker) nor propranolol (a beta-adrenoceptor blocker) showed any significant effects on gastric acid output in hypoxia. These results indicate that acute hypoxia stimulated the adrenergic response from the adrenal medulla, and that gastric acid secretion was consequently suppressed through alpha 2-adrenoceptor.

Adrenal Medulla↗

Atrial septal defect in cyanotic CL/Fr mice.

OBJECTIVE: It is widely known that some newborn CL/Fr mice with cleft lip and palate (CLP) also have cyanotic symptoms, which have been thought to depend on an atrial septal defect (ASD). In a previous study, we found that cyanotic mice tended to have more severe types of CLP. We hypothesize that the mechanical airway obstruction due to a poorly developed palatal shelf and unmoved tongue in CLP(+) mice might be related to the occurrence of cyanosis. The purpose of this study was to examine the relationships between ASD and cyanosis in CLP(+) newborns. METHOD: The newborn hearts from CLP(-), noncyanotic CLP(+), cyanotic CLP(+), CL/Fr mice and ICR mice were examined histologically, and the incidence and size of ASD was determined on neonatal day (ND) 0. In CLP(-) newborns, similar procedures were performed from ND 1 to ND 4. Furthermore, in CLP(+) newborns, development of the palatal shelf was examined. RESULTS: While all the ICR mice had a well-developed atrial septum, and the incidence of ASD was 0%, about 80% of CL/Fr mice had ASD, irrespective of the presence or absence of CLP and cyanosis. On ND 0, the septum primum was significantly shorter in cyanotic CLP(+) mice than in CLP(-) mice. It also tended to be shorter in CLP(+) mice than in CLP(-) mice. Between the cyanotics and noncyanotics, there were no significant differences in the incidences of ASD and the rate of septal development. In CLP(-) mice, the septum primum developed well later and no ASD was observed on ND 4. Cyanotic newborns had significantly less developed palatal shelves than did noncyanotics. CONCLUSIONS: Cyanosis may not be related to ASD and the rate of septal development, but may be related to the occurrence of CLP in this strain. Furthermore, we confirmed that some relationship exists between the development of the palatal shelf and cyanosis. The present study supports our hypothesis concerning the cause of cyanosis in CL/Fr mice.

Airway Obstruction↗

A mesenteric liposarcoma with production of granulocyte colony-stimulating factor.

A 77-year-old female was admitted to our hospital because of pyrexia and a right retroperitoneal mass. Leukocytosis and other inflammatory findings were noted. Bone-marrow aspiration revealed hypercellularity with no malignant cells. An additional mass was detected sonographically in the pelvis. The serum concentration of granulocyte colony-stimulating factor (G-CSF) was highly elevated (299 pg/ml). The tumors were removed at laparotomy, and the pelvic mass was found to arise from the ileocecal mesentery. Postoperatively, white blood cell count and serum G-CSF concentrations decreased to normal levels. The mesenteric tumor showed weakly positive immunostaining for human G-CSF, and Northern and polymerase chain reaction (PCR) analyses detected CSF and its mRNA in the mesenteric tumor.

Aged↗

Mesencephalic projections from superficial and deep laminae of the medullary dorsal horn.

The mesencephalic projection pattern of axons arising from the medullary dorsal horn (MDH) was studied on the basis of axonal transport of Phaseolus vulgaris Leucoagglutinin (PHA-L). After large injections of PHA-L into both the superficial and deep laminae of the MDH, labeled fibers were observed in the anterior pretectal area (ATP), internal gray matter of the superior colliculus (InG), and rostral linear raphe nucleus (RLi) in the contralateral mesencephalon, and also in the ipsilateral parabrachial nucleus (PBA). Restriction of PHA-L to only the superficial laminae resulted in heavy axon labeling and varicosity in the APT and little labeling in the lateral part of the InG of the contralateral mesencephalic nuclei and the dorsal part of the ipsilateral PBA. On the other hand, after injections into the deep laminae, labeled axons were distributed mainly in the contralateral InG and RLi. Therefore, it is concluded that there are two different major pain pathways from the superficial and deep laminae of the MDH to the mesencephalic nuclei, processing nociceptive information in the trigeminal system.

Animals↗

[The history and current state of communication avoidance research].

The ability to communicate effectively has a profound impact on academic ability and social status in the United States. As such, communication avoidance may impart critical consequences on individuals who suffer from it. Within the communication discipline, communication avoidance is an extensive body of research with a relatively long history. Central to communication avoidance research is the concept of communication apprehension (CA). However, in comparison with research conducted in the United States, CA research in Japan remains in its genesis. This review thus focuses on communication apprehension and related constructs. Starting with an explanation of the magnitude of the problem of communication avoidance, a definition of CA is presented, and an overview of the related constructs of reticence, shyness, and other communication-related fears is introduced. Basic CA treatment programs and personality correlates of CA are also covered. The review closes by offering suggestions for future CA research in Japan.

Anxiety↗

[Role of school lunch in primary school education: a trial analysis of school teachers' views using an open-ended questionnaire].

We tried to analyze synthetically teachers' view points associated with health education and roles of school lunch in primary education. For this purpose, a survey using an open-ended questionnaire consisting of eight items relating to health education in the school curriculum was carried out in 100 teachers of ten public primary schools. Subjects were asked to describe their view regarding the following eight items: 1) health and physical guidance education, 2) school lunch guidance education, 3) pupils' attitude toward their own health and nutrition, 4) health education, 5) role of school lunch in education, 6) future subjects of health education, 7) class room lesson related to school lunch, 8) guidance in case of pupil with unbalanced dieting and food avoidance. Subjects described their own opinions on an open-ended questionnaire response sheet. Keywords in individual descriptions were selected, rearranged and classified into categories according to their own meanings, and each of the selected keywords were used as the dummy variable. To assess individual opinions synthetically, a principal component analysis was then applied to the variables collected through the teachers' descriptions, and four factors were extracted. The results were as follows. 1) Four factors obtained from the repeated principal component analysis were summarized as; roles of health education and school lunch program (the first principal component), cooperation with nurse-teachers and those in charge of lunch service (the second principal component), time allocation for health education in home-room activity and lunch time (the third principal component) and contents of health education and school lunch guidance and their future plan (the fourth principal component). 2) Teachers regarded the role of school lunch in primary education as providing daily supply of nutrients, teaching of table manners and building up friendships with classmates, health education and food and nutrition education, and developing food preferences through eating lunch together with classmates. 3) Significant positive correlation was observed between "the teachers' opinion about the role of school lunch of providing opportunity to learn good behavior for food preferences through eating lunch together with classmates" and the first principal component "roles of health education and school lunch program" (r = 0.39, p < 0.01). The variable "the role of school lunch is health education and food and nutrition education" showed positive correlation with the principle component "cooperation with nurse-teachers and those in charge of lunch service" (r = 0.27, p < 0.01). Interesting relationships obtained were that teachers with longer educational experience tended to place importance in health education and food and nutrition education as the role of school lunch, and that male teachers regarded the roles of school lunch more importantly for future education in primary education than female teachers did.

Adult↗

Functional MR imaging of cortical activation of the cerebral hemispheres during motor tasks.

PURPOSE: We used functional MR imaging to evaluate cortical activation in the precentral, central, and postcentral regions of the contralateral and ipsilateral cerebral hemispheres during left- and right-handed motor tasks. METHODS: Ten healthy right-handed volunteers were studied with echo-planner MR imaging (1.5 T) while performing alternating finger apposition tasks with both hands. During the hand tasks, the areas of activated pixels were compared between subregions (precentral, central, and postcentral) of the contralateral and ipsilateral sensorimotor cortex. RESULTS: The activated area of the contralateral sensorimotor cortex was significantly larger than that of the ipsilateral cortex during tasks with either hand, whereas the ipsilateral activated area was significantly larger during the left-handed task than during the right-handed task. Ipsilateral activation was greatest in the precentral region, less in the central region, and least prominent in the postcentral region. CONCLUSIONS: Our results confirmed those of previous investigators that ipsilateral activation is more pronounced during left-sided movements than during right-sided movements. The variation in activation of the precentral, central, and postcentral subregions suggests different roles of the ipsilateral and contralateral hemispheres during motor tasks.

Adult↗