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Biomedical subjects

M Yoshida

Publications and source records attributed to M Yoshida.

At least 289 records · Page 16Linked to original sources
PubMed2001

[Monitoring and prophylaxis].

Invasive deep mycoses following bone marrow and solid-organ transplantation remain a major cause of morbidity and mortality. Species of Candida and Aspergillus account for more than 80% of these mycoses. Because these infections are often difficult to diagnose and treat successfully, antifungal prophylaxis is recommended in high-risk patients. Fluconazole is useful in patients who are at risk of invasive candidiasis, including bone marrow transplants, liver and pancreatic transplants. Although invasive aspergillosis is frequent in patients with bone marrow, lung and heart transplantation, no established methods have been available for its prophylaxis. Recently, efforts to improve the efficiency of diagnostic tests have been directed toward the detection of fungal components or metabolites. The requirements for clinical use (monitoring) are as follows: capability of early diagnosis, quantitative measurement, and easy sampling and simple assay procedure. The detection of plasma (1-3)-beta-D-glucan (BDG), a characteristic cell wall component of almost all fungi, is widely used in Japan. Twenty-seven episodes of fungemia were observed in our hematology ward and all were positive with BDG. Positive results were observed before the documentation of fungemia in 14 patients (51.9%). Although the positive rate of BDG also was 100% in 17 patients with invasive aspergillosis, it rose slightly at an early stage of the disease in 13 patients (76.5%). The determination of plasma BDG appears useful in the monitoring of deep fungal infection, but its usefulness for early diagnosis remains to be determined. The utility of detection of Aspergillus galactomannan by ELISA and fungal DNA by polymerase chain reaction are also discussed.

Animals↗
PubMed2001

[A case of chronic masticator space abscess].

Different neoplasms and infections are known to involve the masticator space, but pathological diagnosis and treatment of these lesions are not always simple due to anatomical complexity. We treated a 66-year-old man with an abscess in the nasopharyngeal masticator space. Physical and CT findings resembled those of neoplastic lesion because the onset dated back 5 years and the patient was lacking in notable signs of infection. Surgery through the maxillary sinus to the lesion enabled us to confirm its pathology and drain pus, with subsequent cure. We noted periodontal infection of the mandibular molars accompanied with osteomyelitis as a cause of this abscess, so infected molars were extracted 13 days after surgery. The infection had spread upward along the mastication muscles, resulting in an abscess in both the upper masseter muscle and the lower temporalis muscle. Based on a review of the literature, most abscesses in the masticator space originate from the mandibular molar, while the most impressive physical finding varied between the submandibular region and temporal fossa, as did its acute or chronic clinical course. Such clinical manifestations appear to reflect the pattern of infection spread along the muscles of mastication and a pattern involving adjacent spaces. We emphasize diagnostic significance when assessing findings for each mastication muscle and mandibular bone depicted using computed tomography, magnetic resonance imaging, and bone-scan technetium.

Abscess↗
PubMed2001

[Clinical and bacteriological significance of the Streptococcus milleri group in deep neck abscesses].

Streptococcus constellatus, S. intermedius, and S. anginosus, the three species of the S. milleri group, form part of the normal flora most commonly found in the mouth, throat, gastrointenstinal tract, and genital tract. The S. milleri group has become known as an important pathogen in abscess disease, but little attention has been paid to their role in deep neck abscesses. We have treated 9 patients with deep neck abscesses relating to the S. milleri group since 1991, and regarded this group as an important pathogen also in these abscesses. We studied the frequency of the S. milleri group isolated from deep neck abscesses in our cases and from the literature and discuss clinical significance and bacteriological pathogenesis. Cases numbered 27 treated at our facility since 1991 and 200 cases reported in the Japanese literature since 1990. Of our 9 cases, 4 originated from acute pharyngitis, 3 from peritonsillar abscesses, and 2 from odontogenic infection. Serious complications such as mediastinitis, cervical necrotizing fasciitis, sepsis accompanied by disseminated intravascular coagulation, and spondylitis of the cervical vertebrae were seen in 4 cases. Among organisms isolated, the S. milleri group appeared to be a pathogen contributing to abscess formation and to serious complications. The genus Streptococcus was most frequently isolated both in our 27 cases (66.7%) and the 200 in the literature (45.5%). Among species of the genus Streptococcus, the S. milleri group numbered the highest in our cases at 33.3% but only 8.5% in the literature. Cases in the literature, however, contained many unknown species of Streptococci--31.5% vs. 18.5% in our cases. alpha-streptococcus was frequently reported in the literature among unknown species of Streptococci--36 of 63. Culture-negative cases were also numbered more in the literature than in our case--29.0% vs. 18.5%. Special conditions and procedures are required to suitably isolate and detect the S. milleri group. Since not all facilities use identical techniques in routine bacteriological examination, a considerable number of the S. milleri group could be missed in unknown species of Streptococci or alpha-streptococcus and culture-negative cases. The detailed pathogenesis of the S. milleri group remains to be clarified. Infection by normal flora on mucosa is thought to occur due to an imbalance between organisms and host defense in deep neck abscesses. Some strains of the S. milleri group have been reported to produce many tissue-destroying enzymes such as collagenase and hyaluronidase. The co-existence of the S. milleri group with some anaerobe strains has also been suggested to accelerate inflammation. We discuss the mechanism inducing the massive release of cytokines through T cell response to certain exotoxins produced by S. milleri group, as reported in toxic shock-like syndrome due to the group A beta-streptococcus and in alpha-streptococcal shock syndrome due to viridans streptococci (alpha-streptococci).

Abscess↗
PubMed2001

[Clinical significance of the Streptococcus milleri group in peritonsillar abscesses].

Few researchers have microbiologically studied peritonsillar abscesses in detail, and their results have been conflicting. Although Streptococcus pyogenes (Group A beta-streptococcus) is commonly considered an important pathogen in this infection, recent studies have demonstrated the recovery of many other streptococci mainly consisting of alpha-streptococci. Few studies have identified these streptococci at the species level, however. We studied details of bacteriology in 31 cases of peritonsillar abscess treated between 1991 and 2000. The Streptococcus milleri group was most frequently isolated (25.8%), followed by Eikenella corrodens (9.7%), Staphylococcus aureus (6.5%), and S. pyogenes (3.2%). The S. milleri group, consisting of 3 species of Streptococcus constellatus, S. intermedius, and S. anginosus, forms part of the normal flora most commonly found in the mouth, throat, gastrointestinal tract, and genital tract. These species have become known as an important pathogen in abscess disease but little attention has been paid to their role in peritonsillar abscesses. To adequately culture the S. milleri group, incubation in air containing carbon dioxide or in an anaerobic condition is required, and then the differentiation of the 3 species requires the biochemical reactivity tests. Since hemolytic patterns of the S. milleri group vary, we studied the population of alpha-, beta-, and gamma-hemolytic strains among 36 strains of this group. We found 32 (88.8%) to be alpha-hemolytic. Although not all alpha-hemolytic strains belong to the S. milleri group, a considerable number of this group could be missed among alpha-streptococci isolated from the peritonsillar abscess. As antibiotics began being used widely, normal flora such as the S. milleri group may have become an important pathogen in peritonsillar abscesses due to an imbalance between organisms and host defense.

Adolescent↗
PubMed2001

[Sequential analysis of p210- and p190-bcr-abl by RT-PCR after allogeneic bone marrow transplantation for p210/p190-bcr-abl double positive acute lymphoblastic leukemia].

In patients with both p210-bcr-abl (p210) and p190-bcr-abl (p190)-positive acute lymphoblastic leukemia, the number of p190 transcripts is lower than that of p210 transcripts. It is speculated that the p190 transcript occurs as a consequence of alternative splicing or missplicing events in the BCR gene. Four patients with both p210- and p190-positive acute lymphoblastic leukemia were studied for expression of p210 and p190 by RT-PCR before and after allogeneic bone marrow transplantation. p190 negativity was documented in all four patients, followed by p210 negativity one to two months later in three patients. These results suggest that negativity for p190 indicates an ongoing decrease in the small number of residual leukemic cells. In one patient p190 appeared transiently in spite of prolonged negativity for p210 18 months after bone marrow transplantation. We conclude that analysis of p210 and p190 is useful for following up patients with both p210- and p190-positive acute lymphoblastic leukemia.

Adult↗
PubMed2001

[Perioperative administration of bicarbonated solution to a patient with mitochondrial encephalomyopathy].

A 16-year-old man with mitochondrial encephalomyopathy underwent biopsy and nephrectomy under general anesthesia. Mitochondrial encephalomyopathy is caused by mitochondrial dysfunction, and frequently accompanies elevation of lactic and pyruvic acid levels in the blood. It has been considered that problems of anesthesia for the patient with mitochondrial encephalomyopathy are the probability of hyperlactacidemia, the relevance to malignant hyperthermia, the possibility of myocardial disease and dysfunction of heart conduction system, respiratory depression due to muscle weakness, and so on. Therefore, to prevent hyperlactacidemia, we prepared the extracellular fluid solution including bicarbonic acid but no lactic and acetic acid, and infused the solution to the patient during anesthesia. By use of this solution, his lactic acid level was kept within the normal range during anesthesia and no metabolic acidosis occurred. His hemodynamics was stable and he showed normal response to vecuronium, recovering from anesthesia smoothly and postoperative course was uneventful.

Acidosis, Lactic↗
PubMed2001

[Complete cytogenetic response obtained with unrelated donor lymphocyte infusion for relapse of chronic myeloid leukemia in blastic crisis after allogeneic bone marrow transplantation].

A 35-year-old man with chronic myeloid leukemia (CML) in blastic crisis (BC) received an allogeneic bone marrow transplant from an unrelated donor in October 1998 after three cycles of chemotherapy. BC relapse developed on day 349 after transplantation. After one cycle of chemotherapy and treatment with interferon, the patient received donor lymphocyte infusion (DLI), and this resulted in a complete cytogenetic response 21 days later. Grade III acute graft-versus-host disease developed on day 25 after DLI, but this was resolved after administration of prednisolone. Disease relapse occurred at extramedullary sites on day 162 after DLI, and the patient died of sepsis after receiving chemotherapy. This case illustrates that unrelated DLI can induce remission successfully in patients with relapse of CML in BC through a graft-versus-leukemia effect.

Adult↗
PubMed2001

Rebamipide inhibits ceramide-induced interleukin-8 production in Kato III human gastric cancer cells.

Helicobacter pylori adheres to gastric epithelial cells and stimulates interleukin-8 production. Ceramide, a lipid second messenger, has become known as an important mediator of some actions of several cytokines. We have recently reported that H. pylori-dependent ceramide production may activate nuclear factor-kappaB and mediate interleukin-8 expression in human gastric cancer cell lines. In this study, we evaluated the effect of rebamipide, an antigastritis and antiulcer agent, on H. pylori-dependent ceramide production and subsequent interleukin-8 expression in Kato III cells. Rebamipide inhibited ceramide-induced interleukin-8 expression in a dose-dependent manner. Rebamipide decreased the ceramide-induced increase of the interleukin-8 mRNA level as assessed by Northern blotting. Rebamipide suppressed interleukin-8 gene transcription and nuclear factor-kappaB-dependent transcriptional activity as assessed by luciferase assay. Rebamipide inhibited the ceramide-induced degradation of IkappaB-alpha (a major cytoplasmic inhibitor of nuclear factor-kappaB), further supporting that rebamipide inhibits the activation of nuclear factor-kappaB. Rebamipide also inhibited the ceramide-dependent activation of mitogen-activated protein kinases. Furthermore, rebamipide significantly attenuated the H. pylori-dependent increase in the intracellular ceramide level. These results suggest a novel mechanism by which rebamipide may protect against the mucosal inflammation associated with H. pylori infection.

Alanine↗
PubMed2001

Immunohistochemical detection of amelogenin and cytokeratin 19 in epithelial odontogenic tumors.

OBJECTIVE: Epithelial odontogenic tumors exhibit considerable histological variation and are classified into several benign and malignant entities. Expression of amelogenin and cytokeratin 19 (CK19), that are potentially useful polypeptides for identification of odontogenic epithelial components, was evaluated in various types of epithelial odontogenic tumors. MATERIALS AND METHODS: Specimens of 33 ameloblastomas, three calcifying epithelial odontogenic tumors (CEOTs), two clear cell odontogenic tumors (CCOTs) and five malignant ameloblastomas were examined by immunohistochemistry using anti-amelogenin and anti-CK19 antibodies. RESULTS: Immunohistochemical reactivity for amelogenin was detected in many peripheral columnar or cuboidal cells and some central polyhedral cells in ameloblastomas, and histological variants showed various degrees of amelogenin expression. Expression of CK19 was diffusely present in neoplastic cells in ameloblastomas, and decreased expression was found in keratinizing cells of acanthomatous variants and some neoplastic cells of desmoplastic variants. In CEOTs, immunohistochemical reactivity for amelogenin was detected in neoplastic cells and intercellular amyloid-like materials, whereas CK19 was expressed in neoplastic cells. CCOTs showed positive reactivity for amelogenin and CK19 in neoplastic cells. Malignant ameloblastomas exhibited various degrees of amelogenin expression with constant CK19 expression in neoplastic cells. CONCLUSION: Diverse types of epithelial odontogenic tumors express amelogenin and CK19, suggesting that these tumors have ameloblastic differentiation or odontogenic epithelial properties.

Ameloblastoma↗
PubMed2001

[Reconstruction of the pulmonary outflow tract without external conduit].

Between October 1987 and December 2000, 50 patients underwent reconstruction of the pulmonary outflow tract without external conduit. The primary malformation was tetralogy of Fallot with pulmonary atresia in 37, double outlet of right ventricle in 4, corrected transposition of the great arteries in 4, transposition of the great arteries with ventricular septal defect and pulmonary stenosis in 4, and double outlet of left ventricle in 2. Mean age at operation was 7.2 years, and mean body weight was 18.3 kg. To reconstruct posterior wall of the pulmonary outflow tract, interposition of autologous pericardium was performed in 24, direct anastomosis between pulmonary trunk and ventriculotomy in 13, longitudinal incision from ventriculotomy through pulmonary trunk in 12, and interposition of left atrial appendage in 1. Anterior wall was reconstructed with monocusp valved outflow patch (MVOP). There was one hospital death and no late death. At 10 years, the freedom from reoperation for pulmonary outflow tract obstruction was 100%, and freedom from reoperation for any cause was 86.6%. Transcatheter stenting for peripheral pulmonary stenosis was performed in 6 patients 2 to 10 months after operation.

Adolescent↗
PubMed2001

[Clinical significance of sentinel node navigation surgery in the treatment of early gastric cancer].

Radical lymphadenectomy is the standard surgical approach even for early-stage gastric cancer with a relatively low incidence of lymph node metastasis because of the limited sensitivity of diagnostic imaging to detect micrometastasis in regional lymph nodes. The sentinel node (SN) concept is one topic among novel diagnostic procedures for micrometastasis. The SN is defined as the first draining node from the primary lesion and it would be the first site of micrometastasis. SN biopsy has been clinically validated and applied for the surgical treatment of malignant melanoma and breast cancer. Although the feasibility of this technique in other solid tumors including gastric cancer is still controversial, there are several reports demonstrating the diagnostic significance of SN mapping in early gastric cancer. We have established radio-guided SN mapping for early gastric cancer, and the diagnostic accuracy using this procedure in cT1N0 cases reached 98%. The radio-guided method allows us to detect the SN in endoscopic surgery quantitatively and reproducibly. Validation of the SN concept in gastric cancer in a multi-centric clinical trial is essential for clinical application of this procedure, including the establishment of a novel, minimally invasive approach for early-stage gastric cancer.

Humans↗
PubMed2001

[A comparison between midline and paramedian approaches for combined spinal-epidural anesthesia].

We compared midline approach with paramedian approach for combined spinal-epidural anesthesia (CSEA) by needle through needle technique. Seventy patients undergoing elective gynecological surgery received CSEA with a 27 G Whitacre spinal needle, which protrudes 12 mm beyond the tip of the Tuohy needle. The successful subarachnoid puncture with first attempt was noted in 33 patients (94%) of midline group (M group), in 31 patients (89%) of paramedian group (P group). At the subarachnoid puncture, skin to epidural space distance (43.2 mm vs 53.4 mm) and protrusion length of spinal needle (5.5 mm vs 8 mm) were significantly longer in the P group than in the M group. Abdominal radiography revealed the flexion of epidural catheter in 19 patients (54%) of M group and in 2 patients (6%) of P group. The choice of midline or paramedian approach for CSEA did not affect the success rate of the subarachnoid puncture, but paramedian approach required longer protrusion length of the spinal needle than midline approach. To raise the success rate of subarachnoid puncture by paramedian approach, a long protruded spinal needle is recommended.

Adult↗
PubMed2001

[A case of polyarteritis nodosa limited to both calves with a low titer of MPO-ANCA].

A-57-year-old woman had suffered from high fever, general malaise, and loss of weight (6 kg) since January, 2000. She was admitted to our hospital in May, 2000, because of gait disturbance following to swelling of bilateral calves with severe pain beside the above symptoms. Laboratory data showed leukocytosis (WBC 10,000/microliter), high ESR (98 mm/hr), positive CRP (3.43 mg/dl), positive ANA (x160), high titer of RA (266 IU/l), and a low titer of MPO-ANCA (18 EU). T 2-weighted magnetic resonance image (MRI) showed intensity area of the M. gastrocnemius. Skin biopsy specimens of the right leg demonstrated necrotizing arteritis of small-sized arteries. These findings supported the diagnosis of limited type of polyarteritis nodosa (PN). In this report, we demonstrate a rare case of PN limited to both calves with characteristic MRI findings and a low titer of MPO-ANCA.

Antibodies, Antineutrophil Cytoplasmic↗