Biomedical subjects
Publications and source records attributed to H Takami.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Bilateral neck explorations for primary hyperparathyroidism have a high cure rate (> 95%) and a low rate of morbidity when performed by experienced surgeons. Despite this. there have been many efforts to minimize the procedure in terms of length and region of incision. cost, extent of exploration, and length of hospital stay, while maintaining an excellent outcome. A renewed interest in unilateral neck exploration for primary hyperparathyroidism developed upon the introduction of sestamibi scintigrams as a new preoperative localization technique. The localization of adenomas using this technique was much more accurate than that of previous localization studies. allowing unilateral procedures to become feasible. Several surgeons have advocated a unilateral approach using preoperative sestamibi scanning. Sestamibi-guided parathyroidectomies enable parathyroidectomies to be performed much more rapidly through a significantly less invasive dissection. This procedure results in a very high cure rate with fewer complications, a smaller neck incision, and less use of post-operative narcotics. In patients with hyperparathyroidism. the intraoperative quick PTH assay allows the success of the procedure to be predicted intraoperatively. The intraoperative quick PTH assay is not only helpful in standard initial parathyroidectomies, but also improves the success rate of reoperative procedures. Its use is mandatory in all minimally invasive procedures. Initial reports regarding this innovation have been extremely positive. Nevertheless, some questions have been raised regarding the accuracy and utility of this procedure. Endoscopic parathyroidectomies offer several opportunities for innovation. Various approaches have been shown to be technically feasible, such as endoscopic procedures that rely on CO, insufflation to create a working space or video-assisted procedures in which the working space is maintained through conventional external retraction.
Familial hyperparathyroidism (HPT) is a hereditary disease in which HPT is transmitted in an autosomal dominant fashion. It includes a variety of diseases: multiple endocrine neoplasia (MEN) type 1 and type 2, and familial isolated hyperparathyroidism (FIHPT). We screened for MEN 1 mutations by direct nucleotide sequencing of all protein-coding regions and identified the germline mutations of the MEN 1 gene in two families with familial HPT. Patients with FIHPT have multiple abnormal parathyroid glands and are prone to both recurrent and persistent HPT. They frequently present with profound hypercalcemia, in contrast to patients with MEN-associated HPT or sporadic HPT. We recommend subtotal or total parathyroidectomy plus autotransplantation in patients with MEN-associated HPT and patients with FIHPT. Because parathyroid remains or supernumerary glands are often present in the thymus or perithymic tissue, we advocate routine bilateral dissection of the central zone with bilateral cervical thymectomy.
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During the last three years, minimally invasive procedures have been adopted for the surgical treatment of primary hyperparathyroidism, because preoperative localization studies such as a high-resolution ultrasonography and sestamibi scintigraphy. guidance by intraoperative scans and the use of a quick, intraoperative PTH assay, have improved. Therefore, endoscopic parathyroidectomy can be performed for patients with primary hyperparathyroidism. The endoscopic procedures range from the 'pure' endoscopic approach characterized by constant gas insufflation and video-assisted gasless techniques. Then, we regard the cosmetic result as important, and adopted the 'pure endoscopic approach because a small incision can be made far from the neck region. We report our technique with no scars in the neck region for endoscopic unilateral neck exploration with primary hyperparathyroidism by an axillary approach and for endoscopic bilateral neck exploration with renal hyperparathyroidism by an anterior chest approach.
Permanent hypoparathyroidism is one of the most difficult of all endocrine disorders to treat medically. To examine the possibility that xenotransplantation can be used to treat hypoparathyroidism, human parathyroid tissues were transplanted into mice. Human parathyroid tissue was taken from specimens excised from patients with hyperparathyroidism. Fresh human parathyroid tissue was implanted under kidney capsule of CBA (H2k) mice. Some mice were treated intraperitoneally with depleting anti-CD4 monoclonal antibody (mAb, YTA 3.1, 100 microg/dose, days -1. 0. 1, 2, 3, and 5). Mice were killed 30 days after transplantation. Survival of parathyroid grafts was examined microscopically and human parathyroid hormone in serum was measured by ELISA. All parathyroid grafts survived under kidney capsule and human parathyroid hormone was strongly detected in serum (621 +/- 576 pg/mL) when recipients were treated with short-course treatment of anti-CD4 mAb. Conversely, no parathyroid tissue was seen microscopically in any recipient mice without anti-CD4 mAb treatment. Human parathyroid hormone was undetectable by ELISA in naive mice and mice transplanted with human parathyroid tissue without short-course treatment of anti-CD4 mAb. Xenogeneic human parathyroid tissue survived and functioned in mice treated with short-course treatment of anti-CD4 mAb.
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We describe a rare case of acute myeloid leukaemia with trilineage myelodysplasia complicated by central diabetes insipidus. In the present case, diabetes insipidus was masked by corticosteroid deficiency due to hypopituitarism and clinical symptoms presented after administering methylprednisolone. Although the remission of leukaemia was not achieved by chemotherapy, excessive urinary output was well-controlled by nasal administration of 1-desamino-8-D-arginine vasopressin (DDAVP) during the course.
The staphylococcal exfoliative toxins (ETs) are extracellular proteins that cause splitting of human skin at the epidermal layer during infection in infants. Two antigenically distinct toxins possessing identical activity have been isolated from Staphylococcus aureus, ETA and ETB. The gene for ETA (eta) is located on the chromosome, whereas that for ETB is located on a large plasmid. The observation that relatively few clinical isolates produce ETA suggests that the eta gene is acquired by horizontal gene transfer. In this study, we isolated a temperate phage (phiETA) that encodes ETA and determined the complete nucleotide sequence of the phiETA genome. phiETA has a head with a hexagonal outline and a non-contractile and flexible tail. The genome of phiETA is a circularly permuted linear double-stranded DNA, and the genome size is 43 081 bp. Sixty-six open reading frames (ORFs) were identified on the phiETA genome, including eta, which was found to be located very close to a putative attachment site (attP). phiETA converted ETA non-producing strains into ETA producers. Southern blot analysis of chromosomal DNA from clinical isolates suggested that phiETA or related phages are responsible for the acquisition of eta genes in S. aureus.
BACKGROUND: Endocrine allografts are an option for the treatment of endocrine failure. METHODS: One lobe of the thyroid was transplanted under the kidney capsule. RESULTS: C57BL/10 (H2(b)) thyroids were rejected in naive CBA (H2(k)) mice within 14 days after transplantation. When mice were treated with anti-CD4 monoclonal antibodies (mAb), all grafts survived for more than 60 days. The first grafts still survived after second C57BL/10 or Balb/c (H2(d)) thyroid grafts that were transplanted into the same recipients were rejected acutely, which suggests that the primary grafts were modified under anti-CD4 mAb treatment. To confirm this hypothesis, C57BL/10 thyroid grafts from anti-CD4 mAb-treated mice were retransplanted. All grafts survived in naive mice; this correlated with the overexpression of heme oxygenase-1 (HO-1) in the grafts. Next, an inhibitor of HO-1 (zinc protoporphyrin) or control compound (copper protoporphyrin) was injected intraperitoneally after transplantation of C57BL/10 thyroid grafts into the primary CBA recipients that had been treated with anti-CD4 mAb. The grafts in mice that had been treated with zinc protoporphyrin, but not copper protoporphyrin, were rejected when retransplanted to naive recipients. CONCLUSIONS: Overexpression of HO-1 correlated with the protection of fully allogeneic thyroid grafts from rejection when retransplanted into naive recipients.
BACKGROUND: The aggressiveness of familial non-medullary thyroid cancer (FNMTC) has been a subject of debate. The purpose of the study was to determine whether FNMTC is more aggressive than sporadic thyroid cancer. METHODS: A multicenter retrospective matched-case control study of FNMTC versus sporadic non-medullary thyroid cancer was conducted. Disease-free survival (time to recurrence) for both groups was compared. RESULTS: Forty-eight familial cases were compared with 144 age-, gender-, and stage-matched controls. Patients with FNMTC had a significantly shorter disease-free survival compared with sporadic non medullary thyroid cancer. Patients with FNMTC who presented with evidence of distant metastasis, or who were from families with more than 2 thyroid cancer-affected members, had the worst prognosis. The available staging systems were less likely to predict the outcome in patients with FNMTC than in patients with sporadic non-medullary thyroid cancer unless one accounted for the strength of family history in the staging system. CONCLUSIONS: FNMTC is more aggressive than sporadic non-medullary thyroid cancer. The best predictors of a poor outcome in patients with FNMTC are the number of family members affected by thyroid cancer and evidence of distant metastasis.
It is known that some products of endothelial cells or their analogs can attenuate the platelet aggregation response and initiate the platelet disaggregation response. Since platelets are involved in the initiation of many clinically important occlusive vascular diseases, we hypothesized that the endothelial cell products act synergistically to disperse platelet aggregates. In this study we examined the synergistic platelet disaggregating effects among the products of endothelial cells. We used urokinase, prostaglandin I2 (PGI2), and sodium nitroprusside (SNP) (which is the chemical substitute as nitric oxide(NO)-donor) for endothelium-derived relaxing factor (EDRF). Platelet disaggregation rate was increased in a dose-dependent manner and decreased in a time-dependent manner, and the combined use of two or three agents had synergistic effects on platelet disaggregation. Furthermore, flow cytometric analysis showed decreases in the binding of fibrinogen to activated platelets by the addition of PGI2 or SNP. These data revealed that these products or their analogs could inactivate the activated platelets or aggregated platelets by detaching fibrinogen from platelets. In addition our data revealed that PGI2 and SNP can act synergistically with fibrinolytic agents. These findings suggest a potential strategy for improving the efficacy of thrombolytic therapy by a combination of these products or their substitutes.
A series of 4-phenoxybutyric acid derivatives attached to a tricyclic skeleton were prepared and evaluated as 5alpha-reductase inhibitors. Structure activity relationships for these compounds in terms of rat epididymis (type 2) 5alpha-reductase inhibitory activities reveal that 1) the substitution pattern at the 11-position of dibenz[b,e]oxepin influenced potency, 2) higher lipophilicity of the tricyclic skeleton improved potency, whereas the existence of a basic nitrogen atom in this skeleton was detrimental to potency, and 3) isobutyl substitution at the 8 positon of the azepine skeleton was tolerated. Among the tricyclic compounds studied, 4-[3-[5-benzyl-8-(2-methyl)propyl-10,11-dihydrodibenz[b,f]azepine- 2-carboxamido]phenoxy]butyric acid (26) was the most potent inhibitor of rat type 2 5alpha-reductase at 0.1 microM.
We developed a semi-automated genome analysis system called GAMBLER in order to support the current whole-genome sequencing project focusing on alkaliphilic Bacillus halodurans C-125. GAMBLER was designed to reduce the human intervention required and to reduce the complications in annotating thousands of ORFs in the microbial genome. GAMBLER automates three major routines: analyzing assembly results provided by genome assembler software, assigning ORFs, and homology searching. GAMBLER is equipped with an interface for convenience of annotation. All processes and options are manipulatable through a WWW browser that enables scientists to share their genome analysis results without choosing computer platforms.
A barotolerant member of the genus Pseudomonas was isolated from deep-sea sediment obtained from the Japan Trench, at a depth of 4418 m. The growth temperature was found to affect the hydrostatic pressure range in which the bacterium could grow; the optimum hydrostatic pressure for growth shifted to a higher pressure with increasing temperature. We examined the lipid composition of the inner membrane of cells grown at various hydrostatic pressures and temperatures. The fatty acid components of the inner membrane lipids were C16:0, C16:1, C18:0, and C18:1. The phospholipid components of the inner membrane were phosphatidylethanolamine, cardiolipin, phosphatidylglycerol, and phosphatidylserine. It is evident that the effects of elevated hydrostatic pressure are comparable to the effects of low temperature on both the fatty acid composition of the inner membrane lipids and the phospholipid composition of the inner membrane of this bacterium.