Search PubMed⌕ Search

Biomedical subjects

Takashi Sugita

Publications and source records attributed to Takashi Sugita.

At least 19 recordsLinked to original sources
PubMed2006

Conservative surgery for well-differentiated liposarcomas of the extremities adjacent to major neurovascular structures.

BACKGROUND: There is no clear consensus as to the appropriate nomenclature and the best surgical strategy for well-differentiated liposarcomas. A wide surgical excision is recommended over marginal resection for local control of well-differentiated liposarcomas. However, this surgical procedure should be reconsidered for lesions, which come into contact with major neurovascular structures. METHODS: Between 1998 and 2004, 12 well-differentiated liposarcomas of the extremities were treated at our institute. Among them, nine lesions (75%) adjacent to major nerves or blood vessels were marginally resected with careful dissection of these critical structures. The clinical outcomes were reviewed for a mean follow-up time of 4 years. RESULTS: Seven patients continued to be disease-free without any loss of limb function. One patient developed a local recurrence 30 months postoperatively. The other patient with a foot lesion involving the fourth metatarsal bone has experienced slight difficulty in gait-balancing due to the fourth toe amputation, but remains free of disease. The local control rate was 88.9%, even though seven lesions were resected with positive surgical margins. CONCLUSIONS: Our findings suggested that well-differentiated liposarcomas frequently arise in close proximity to major nerves or blood vessels. Marginal resection alone seems to be adequate for these lesions to preserve critical structures.

Adult↗
PubMed2006

Cytokine secretion profile of human keratinocytes exposed to Malassezia yeasts.

The lipophilic yeast Malassezia is an exacerbating factor in atopic dermatitis (AD). Among organisms of the Malassezia species, Malassezia globosa and Malassezia restricta are particularly dominant on the skin of AD patients. However, the precise role of Malassezia yeasts in the pathophysiology of AD remains uncertain. Keratinocytes play a critical role in cutaneous inflammatory and immune responses by secreting cytokines. In this study, we attempted to determine the cytokine secretion profiles of human keratinocytes that were exposed to Malassezia yeasts. The human keratinocyte cell line PHK16-0b was cocultivated with M. globosa or M. restricta for 24 h, and the resulting cytokine secretion profile was analysed using a cytokine antibody array. The keratinocytes responded to the two Malassezia species with different Th2-type cytokine profiles, i.e. M. globosa induced IL-5, IL-10 and IL-13 secretion from the keratinocytes, whereas M. restricta induced IL-4 secretion. Similar results were obtained with primary normal human epidermal keratinocytes. cDNA microarray analysis confirmed that IL-5, IL-10, and IL-13 mRNAs were induced only by M. globosa, while IL-4 mRNA expression was induced only by M. restricta. These findings suggest that M. globosa and M. restricta play a synergistic role in triggering or exacerbating AD by stimulating the Th2 immune response.

Cells, Cultured↗
PubMed2006

A nationwide survey of Trichophyton tonsurans infection among combat sport club members in Japan using a questionnaire form and the hairbrush method.

BACKGROUND: The emerging outbreak of Trichophyton tonsurans infection among members of combat sports clubs in Japan during the last 4 years has become a serious public health problem. To overcome this outbreak, a survey for T. tonsurans infection in Japan may be essential. OBJECTIVES: We sought to clarify the prevalence of T. tonsurans infection among members of combat sports clubs in Japan. METHODS: We conducted a survey of members of participating combat sports clubs using a standardized questionnaire to assess background factors and using the hairbrush method to identify T. tonsurans infection. Statistical significance of the correlation between data from the questionnaire and the hairbrush culture results was determined. RESULTS: We surveyed 1000 people (826 male) from 49 institutions and found 115 (11.5%) were positive for T. tonsurans infection revealed by the hairbrush method. Demographic factors associated with high positive rates (> or =20%) of the infection were familial T. tonsurans infection (20.0%), history of tinea corporis (24.2%), increased dandruff (32.1%), and concomitant tinea corporis (31.6%). Those with positive hairbrush culture results without current or previous tinea were considered asymptomatic carriers. LIMITATIONS: The study population was limited to members of judo clubs all over Japan; they were asked to participate in this survey via the All Japan Judo Federation. CONCLUSION: Infection of T. tonsurans appears to have spread widely among members of combat sports club in Japan. The questionnaire used in this study is a simple and useful tool to estimate epidemiology of this infection.

Adolescent↗
PubMed2006

Fulminating fungal sinusitis caused by Valsa sordida, a plant pathogen, in a patient immunocompromised by acute myeloid leukemia.

We describe a case in which a patient immunocompromised by acute myeloid leukemia experienced acute fulminating invasive fungal sinusitis followed by pneumonia and then death. Though the microbiology of the pneumonia could not be directly investigated, nasal lesions revealed fungal mycelium. Valsa sordida was consistently cultured from a biopsied sample. The fungus was identified to the genus level based on morphology in culture and DNA sequence homology, and then was placed at species level by means of phylogenetic analysis of the nuclear ribosomal internal transcribed spacer region. The fungus is in the order Diaporthales, family Valsaceae in the Ascomycota and is distributed worldwide as a pathogen of trees in the genera Populus and Salix. Koch's postulates were demonstrated to apply in a neutropenic rat model. The fungus was susceptible to antifungals with MIC-0 scores of 0.0313 microg/ml for amphotericin B, 0.25 microg/ml for voriconazole, 0.0313 microg/ml for caspofungin, and MIC-2 of 16 microg/ml for fluconazole. This is the first substantiated report of an isolate in the genus Valsa (anamorph Cytospora) being identified in human disease.

Animals↗
PubMed2006

Tween 40-based precipitate production observed on modified chromogenic agar and development of biological identification kit for Malassezia species.

We developed a simple identification kit for nine species of Malassezia (M. furfur, M. slooffiae, M. sympodialis, M. restricta, M. obtusa, M. globosa, M. pachydermatis, M. dermatis, and M. japonica) based on their biological features. This method utilizes Tween 40-based precipitate production on modified chromogenic agar (CHROMagar) Malassezia medium, growth on specific agars (Sabouraud's dextrose agar, Cremophor EL agar, Tween 60-esculin agar), and catalase reactions. This identification kit was verified with 11 type and reference strains of nine Malassezia species. An additional 26 clinical isolates were also successfully identified using the kit and the results were confirmed by molecular biological analysis.

Agar↗
PubMed2006

A Chinese-Japanese boy with black dot ringworm due to Trichophyton violaceum.

A 4-year and 8-month-old Chinese-Japanese boy, who had been visiting Dalian, China frequently, developed multiple alopecia lesions 1 year previously. At his initial visit to our department, multiple patchy alopecia with black dots was observed in the parietal scalp area. Multiple erythematous macules were also seen on the face, nape and right dorsum of the hand. A diagnosis of tinea capitis and tinea corporis was obtained on the basis of potassium hydroxide (KOH) microscopic examination of hair and scales from the lesions. Colonies grown on Sabouraud cycloheximide-chloramphenicol agar culture were examined using Fungi-Tape and MycoPerm-blue, and numerous microconidia and a small number of macroconidia were observed. Trichophyton violaceum was identified as the causative organism on the basis of colony morphology, microscopic morphology and molecular biology technique. As T. violaceum infection is not often seen in Japan, we suspected that the patient was infected by T. violaceum during his stay in Dalian. Conidia formation is rarely observed with T. violaceum, and only five cases with T. violaceum macroconidia formation have been reported in Japan (including this case). We also report the method for visualizing conidia formation of T. violaceum using Fungi-tape and MycoPerm-blue.

Asian People↗
PubMed2006

Genotype analysis of the variable internal repeat region in the rRNA gene of Trichophyton tonsurans isolated from Japanese Judo practitioners.

Tinea capitis due to Trichophyton tonsurans is currently epidemic among Japanese Judo practitioners. T. tonsurans has seven genotypes in a variable internal repeat (VIR) region of the rRNA gene. All 101 isolates obtained from Japanese Judo practitioners had the identical genotype. This suggests that a specific genotype strain occurs throughout Japan.

Adolescent↗
PubMed2006

Candida pseudohaemulonii Sp. Nov., an amphotericin B-and azole-resistant yeast species, isolated from the blood of a patient from Thailand.

Candida haemulonii(types I and II) is rarely isolated from clinical specimens. We isolated a strain that is phylogenetically close to C. haemulonii from the blood of a Thai patient, and named it C. pseudohaemulonii sp. nov. (CBS 10099T = JCM 12453T = DMST 17134T). The new species and C. haemulonii types I and II were resistant to amphotericin B and azole agents but were susceptible to a 1,3-beta-D-glucan synthetase inhibitor, micafungin, and 5-flucytosine. The species were easily distinguished using an ID32 yeast identification kit. The taxonomic description of C. pseudohaemulonii sp. nov. is presented.

Amphotericin B↗
PubMed2006

Time-kill assay of itraconazole against Malassezia species.

The in vitro pharmacodynamic activity of itraconazole against Malassezia was determined by time-kill methods. Itraconazole showed fungistatic activity at concentrations greater than 2x minimum inhibitory concentration (MIC) for each of the isolates of all nine Malassezia species associated with humans. A concentration exceeding 4x MIC decreased the growth to less than the inoculum amount (1 x 10(5) cells/ml).

Antifungal Agents↗
PubMed2006

Detection and quantification of specific IgE antibodies against eight Malassezia species in sera of patients with atopic dermatitis by using an enzyme-linked immunosorbent assay.

The lipophilic yeast Malassezia, a member of the cutaneous microflora, is an exacerbating factor in atopic dermatitis (AD). Of the 11 currently recognized species, M. globosa and M. restricta are found to frequently colonize the skin of AD patients. In this study, we attempted to quantify specific IgE antibodies against eight Malassezia species, namely, M. dermatitis, M. furfur, M. globosa, M. obtusa, M. pachydermatis, M. slooffiae, M. sympodialis, and M. restricta, in sera from AD patients by using an enzyme-linked immunosorbent assay (ELISA). The specific IgE value against M. restricta was greater than those against other Malassezia species. Competitive ELISA inhibition tests revealed that M. restricta contained species specific as well as shared antigens. Therefore, M. restricta could be considered as a candidate diagnostic antigen for detecting anti-Malassezia IgE in sera from AD patients.

Adolescent↗
PubMed2006

Bullera koratensis sp. nov. and Bullera lagerstroemiae sp. nov., two new ballistoconidium-forming yeast species in the Trichosporonales clade isolated from plant leaves in Thailand.

Seven strains of ballistoconidiogenous yeasts that contain xylose, form Q-10 ubiquinone, propagate by budding and don't produce stalk conidia were isolated from plant leaves collected in Thailand and were found to represent two new species. The taxonomic properties of the two species coincided with the genus Bullera so they are described as Bullera koratensis sp. nov. and Bullera lagerstroemiae sp. nov. In phylogenetic trees based on the nucleotide sequences of 18S ribosomal DNA and the D1/D2 domain of 26S rDNA, these two species are located in the Trichosporonales clade (Cryptococcus humicola-Trichosporon lineage).

Base Sequence↗
PubMed2005

Nerve tolerance to high-dose-rate brachytherapy in patients with soft tissue sarcoma: a retrospective study.

BACKGROUND: Brachytherapy, interstitial tumor bed irradiation, following conservative surgery has been shown to provide excellent local control and limb preservation in patients with soft tissue sarcomas (STS), whereas little is known about the tolerance of peripheral nerves to brachytherapy. In particular, nerve tolerance to high-dose-rate (HDR) brachytherapy has never been properly evaluated. In this study, we examined the efficacy and radiation neurotoxicity of HDR brachytherapy in patients with STS in contact with neurovascular structures. METHODS: Between 1995 and 2000, seven patients with STS involving the neurovascular bundle were treated in our institute with limb-preserving surgery, followed by fractionated HDR brachytherapy. Pathological examination demonstrated that 6 patients had high-grade lesions with five cases of negative margins and one case with positive margins, and one patient had a low-grade lesion with a negative margin. Afterloading catheters placed within the tumor bed directly upon the preserved neurovascular structures were postoperatively loaded with Iridium-192 with a total dose of 50 Gy in 6 patients. One patient received 30 Gy of HDR brachytherapy combined with 20 Gy of adjuvant external beam radiation. RESULTS: With a median follow-up of 4 years, the 5-year actuarial overall survival, disease-free survival, and local control rates were 83.3, 68.6, and 83.3%, respectively. None of the 7 patients developed HDR brachytherapy-induced peripheral neuropathy. Of 5 survivors, 3 evaluable patients had values of motor nerve conduction velocity of the preserved peripheral nerve in the normal range. CONCLUSION: In this study, there were no practical and electrophysiological findings of neurotoxicity of HDR brachytherapy. Despite the small number of patients, our encouraging results are valuable for limb-preserving surgery of unmanageable STS involving critical neurovascular structures.

Adolescent↗
PubMed2005

Clinical outcomes of 54 pelvic osteosarcomas registered by Japanese musculoskeletal oncology group.

BACKGROUND: To determine the clinical outcomes in patients with pelvic osteosarcoma, we reviewed the experience with 54 pelvic osteosarcoma patients. METHODS: Thirty-five patients underwent surgical treatment with 30 undergoing limb salvage procedures and 5 requiring hemipelvectomies. RESULTS: Oncological outcome was continuously disease free in 12 cases, no evidence of disease in 3, alive with disease in 3, died of disease in 34 and died of other causes in 2. The 5-year survival rate was 29.5%. For the patients who underwent surgery, statistically significant prognostic factors were chemotherapy, surgical margin, tumor location in sacrum, efficacy of chemotherapy, local recurrence, metastasis and treatment for metastases. With univariate analysis, local recurrence, surgical margin and tumors resected from the sacrum were significant prognostic factors for metastasis. Surgical margin, tumor resected from sacrum and metastasis were significant prognostic factors for local recurrence. With regard to postoperative functional mobility, patients with tumors resected from the sacrum exhibited poorer functional mobility when compared with other sites. CONCLUSIONS: Patients with tumors located in the sacrum had worse prognosis, and significant prognostic factor for local recurrence and metastasis. Treatment of pelvic osteosarcoma especially located in the sacrum requires new approaches and further improvements in order to ensure successful outcomes.

Adolescent↗
PubMed2005

Efficiency of magnetic liposomal transforming growth factor-beta 1 in the repair of articular cartilage defects in a rabbit model.

We evaluated the efficacy of a magnetic liposomal delivery system of transforming growth factor (TGF)-beta(1) in the treatment of articular cartilage defects in a rabbit model. Articular cartilage defects were created in the patellar groove of rabbits, and a permanent magnet or a nonmagnetic alloy was implanted in the defect site. Magnetic liposomal drugs, prepared by the conventional film method and sonication, were injected into the defect site 1 week after surgery. First, the efficacy of the magnetic liposomal delivery system was evaluated by using a model compound fluorescence-labeled dextran 40,000 (FD-40). Then, the therapeutic efficiency of magnetic liposomal TGF-beta(1) was evaluated by cartilage histological scoring at 4, 8, and 12 weeks after surgery. The injected magnetic liposomal FD-40 accumulated at the target site where a permanent magnet had been implanted. The histological score showed that the injection of magnetic liposomal TGF-beta(1) under magnetic force was significantly effective in the repair of the defect site over 12 weeks after surgery. Injection of TGF-beta(1) into the cartilage defect was effective as a magnetic liposomal preparation under magnetic force, resulting in acceleration of the cartilage repair, probably because of the desirable accumulation of TGF-beta(1) at the target site.

Animals↗
PubMed2005

Reconstructed patellar tendon length after proximal tibia prosthetic replacement.

A common problem after proximal tibia prosthetic reconstruction is insufficient extensor mechanism or extensor lag. Maintaining the reconstructed patellar tendon length is an important way to minimize extensor lag. We measured the patellar tendon length and extensor lag serially. From 1994-2003, seven consecutive patients with malignant bone tumors of the proximal tibia had prosthetic reconstruction. The extensor mechanism was reconstructed by reattachment of the patellar tendon to the prosthesis with a synthetic material and augmented by a gastrocnemius flap. The patellar tendon length was measured according to the Insall-Salvati ratio. The ratios at 30 degrees knee flexion decreased immediately postoperatively, and reverted to almost the same preoperative values within 18 months. The mean ratios at 60 degrees knee flexion are significantly greater than 30 degrees at 6 months postoperatively. These findings indicate that the patellar tendon stretched, whereas the extensor lag improved continuously for 12 months postoperatively. In the revision at 22 months postoperatively, although the patellar tendon was not reattached to the replaced prosthesis, the ratio and the extensor lag had not worsened. These results show that providing strong continuity of the patellar tendon, gastrocnemius flap, and leg extensors can decrease the extensor lag, although the patellar tendon stretches.

Adolescent↗