Search PubMed⌕ Search

Biomedical subjects

H Yajima

Publications and source records attributed to H Yajima.

At least 109 records · Page 6Linked to original sources
PubMed1995

Partial soleus muscle island flap transfer using minor pedicles from the posterior tibial vessels.

A new method for partial soleus muscle island flap transfer using minor pedicles from the posterior tibial vessels was designed and executed. A portion of the soleus muscle body that was slightly wider than the defect was harvested with minor pedicles. The muscle flap was transposed by turning it over or by creating an island flap. Skin grafts were applied to the exposed muscle. This new type of muscle flap was applied to six patients with a pretibial skin defect at the lower third of the leg. It was used for treatment of an open fracture with an associated skin defect in four patients, chronic osteomyelitis in one patient, and a recurrent stasis ulcer in one patient. In all patients the transferred muscle flap survived completely.

Aged↗
PubMed1995

Changes in prostatic thickness and the location of ejaculatory ducts in autopsy prostates.

OBJECTIVE: To measure prostatic thickness and the depth of ejaculatory ducts from the urethral surface to prevent ejaculatory duct damage during transurethral balloon laser thermotherapy. MATERIALS AND METHODS: In 47 prostates obtained at autopsy, the prostatic thickness and the depth of ejaculatory ducts from the urethral surface were measured in eight directions from the centre of the urethra. RESULTS: The depth of ejaculatory ducts was approximately 6 mm from the urethral surface regardless of prostatic weight. Increase in prostatic weight was associated with increase in the thickness in all directions except the posterior one; the thickness ranged from 9 to 20 mm. The posterior thickness at the level of the transition zone was 10 mm regardless of prostatic weight. CONCLUSION: When benign prostatic hypertrophy is treated transurethrally, using laser or microwave equipment, care should be taken to avoid heating the posterior region of the prostate.

Adult↗
PubMed1995

Differences in cellular transport of tri-iodothyronine and thyroxine: cell cycle-dependent alteration of tri-iodothyronine uptake.

Cellular and nuclear uptake of tri-iodothyronine (T3) and thyroxine (T4) was examined using the cultured cell line derived from rat liver, clone 9, and rat hepatoma, dRLH-84. The saturable cellular uptake of T3 and T4 was demonstrated in these cells. First we examined the cell cycle-dependent alteration of thyroid hormone uptake. Cellular T3 uptake was minimal in the early G1 phase and increased in the late G1 phase, reaching a maximal level in the S phase. Alterations in nuclear T3 uptake were in accordance with the changes in cellular T3 uptake. On the other hand, cellular and nuclear T4 uptake was unchanged throughout the cell cycle, suggesting the T3 specificity of the cell cycle-dependent alteration of cellular hormone transport. Next we examined the effect of sodium butyrate on the cellular transport of thyroid hormones. After treatment with 5 mM sodium butyrate, cellular and nuclear uptake of T3 was increased, reaching a maximal level (four- to sevenfold increase) after 48 h. When cells were incubated for 48 h with various concentrations of sodium butyrate, T3 uptake was enhanced by 1 mM sodium butyrate, reaching a maximal level with 5 mM. Although cellular T4 uptake was also increased after treatment with sodium butyrate, the degree and time-course of the increase were different from those of T3. The maximal increase in cellular T4 uptake (two- to threefold increase) was attained 20 h after treatment. Despite the increase in cellular T4 uptake, nuclear T4 uptake was decreased after treatment with sodium butyrate. For both T3 and T4, the enhanced cellular uptake was due to the increased Vmax without changes in the Michaelis-Menten constant. These data indicate that cellular transport of T4 is different from that of T3 in rat hepatic cells.

Animals↗
PubMed1995

[Respiratory function in students who had asthma in childhood].

Students who had asthma in childhood can be divided into three groups: "asthma-remission" group "asthma-relapsing" group and "non-asthma-remission" group. When we made inquiries about three different groups, the incidence of each group was 58%, 27% and 15%, respectively. In order to determine if childhood asthma affects respiratory function in adulthood, we measured respiratory functions by spirometry in 26 students who had asthma in childhood, and in seven control students. There was no significant difference between students with childhood asthma and control students in terms of FEV1.0% of predicted value. However, students who had asthma in childhood had lower levels of V25/HT% of predicted value in comparison with control students. The effects of deep inhalation in the three groups were evaluated by determining the values of maximal expiratory flow at 40% (MEF40) of vital capacity from partial (P) and maximal (M) flow-volume curves. There was no difference between the remission group and the control group in the MEF40 M/P ratio. This suggests that childhood asthma may deteriorate respiratory functions in adulthood by remodeling of peripheral airways.

Adult↗
PubMed1994

A new class of DNA photolyases present in various organisms including aplacental mammals.

DNA photolyase specifically repairs UV light-induced cyclobutane-type pyrimidine dimers in DNA through a light-dependent reaction mechanism. We have obtained photolyase genes from Drosophila melanogaster (fruit fly), Oryzias latipes (killifish) and the marsupial Potorous tridactylis (rat kangaroo), the first photolyase gene cloned from a mammalian species. The deduced amino acid sequences of these higher eukaryote genes show only limited homology with microbial photolyase genes. Together with the previously cloned Carassius auratus (goldfish) gene they form a separate group of photolyase genes. A new classification for photolyases comprising two distantly related groups is proposed. For functional analysis P.tridactylis photolyase was expressed and purified as glutathione S-transferase fusion protein from Escherichia coli cells. The biologically active protein contained FAD as light-absorbing cofactor, a property in common with the microbial class photolyases. Furthermore, we found in the archaebacterium Methanobacterium thermoautotrophicum a gene similar to the higher eukaryote photolyase genes, but we could not obtain evidence for the presence of a homologous gene in the human genome. Our results suggest a divergence of photolyase genes in early evolution.

Amino Acid Sequence↗
PubMed1994

New disulfide bond-forming reactions for peptide and protein synthesis.

1. In order to solve the difficult problems for the synthesis of peptides or proteins containing several disulfide bonds, three new disulfide bond-forming reactions were developed. 2. Thallium(III) trifluoroacetate oxidation. This reagent, a mild oxidant with a soft acid character, cleaved various S-protecting groups of cysteine in trifluoroacetic acid, with spontaneous formation of cystine. Thus, some model peptides containing a disulfide bond were prepared by direct oxidative conversion of the respective S-substituted cysteine peptides. 3. Sulfoxide-directed disulfide bond-forming reaction. The disulfide bond was formed at the sulfur atom of Cys(R)(O) (sulfoxide) intermolecularly as well as intramolecularly following liberation of the SH group from the coreactant, Cys(R'), by a suitable acid. Thus, formation of the disulfide bond was found to be feasible at the position of Cys(R)(O). 4. Silylchloride-sulfoxide procedure. In the presence of diphenylsulfoxide, methyltrichlorosilane in trifluoroacetic acid cleaved various S-protecting groups to form cystine within 10 to 30 min at 4 degrees C. By combination of this new disulfide bond-forming reaction and others, some peptides containing two or three disulfide bonds were synthesized successfully.

Amino Acid Sequence↗
PubMed1994

Venous flap--its classification and clinical applications.

We previously reported pedicled venous flap survival using the rat model, as well as venovenous, arteriovenous, and arterialized flow-through venous flap survival using the rabbit ear model. For this study, we utilized these flaps clinically. Five of seven pedicled venous flaps survived, displaying superficial necrosis. The others became partially necrotic; they were transferred after dissection of a long pedicle vein. Eight of nine venovenous flow-through venous flaps survived; six displayed superficial necrosis. The nonsurviving flap became completely necrotic, possibly because only one donor vein and one recipient vein were used. Six of 10 arteriovenous flow-through venous flaps survived. The remaining four became partially necrotic, possibly because only one vein was anastomosed for outflow. The arterialized flow-through venous flap survived. The pedicled venous and venovenous groups studied seem likely to survive despite superficial necrosis. However, the draining vein should not be dissected more than 5 cm, and many draining veins should be anastomosed with recipient vessels.

Adult↗
PubMed1994

Lanthanide ions for the first non-enzymatic formation of adenosine 3',5'-cyclic monophosphate from adenosine triphosphate under physiological conditions.

Adenosine 3',5'-cyclic monophosphate (cAMP) is formed from adenosine triphosphate at pH 8 and 50 degrees C by use of lanthanide ions. Pr3+ and La3+ are the most active. The cAMP formation is more efficient at higher pH, where the mixture is made homogeneous by the addition of beta-cyclodextrin. The potential functioning of lanthanide ions as the catalytic center of an artificial adenylate cyclase is indicated.

Adenosine Triphosphate↗
PubMed1994

Proximal lateral leg flap transfer utilizing major nutrient vessels to the soleus muscle.

A new skin flap based on the cutaneous branches of the major nutrient vessel to the soleus muscle was designed and executed. An anatomic study of the major nutrient artery to the lateral half of the soleus muscle was performed on 26 legs. An angiographic study was performed on 27 legs. The major nutrient artery to the lateral half of the soleus muscle was classified according to its origin: the tibioperoneal trunk (type 1), the bifurcation of the posterior tibial and peroneal arteries (type 2), the posterior tibial artery (type 3), and the peroneal artery (type 4). The outer diameter of the major nutrient artery to the lateral half of the soleus muscle, by direct measurement, was 1.87 mm (range 1.1 to 2.5 mm). This new flap was applied in nine patients. The recipient sites were the great toe, the hand, the jaw, the anterior leg, the popliteal fossa, and the thigh. The vascular pedicle ranged from 6.5 to 9.5 cm in length. Tissue was transferred as a free flap in eight patients and as an island flap in one patient. All the flaps survived completely.

Adolescent↗
PubMed1994

DNA photolyase from the fungus Neurospora crassa. Purification, characterization and comparison with other photolyases.

A phr-gene from the filamentous fungus Neurospora crassa was overexpressed in Escherichia coli cells, yielding a biologically active photolyase. After purification till apparent homogeneity, the 66 kDa protein was found to contain equimolar amounts of 5,10-methenyltetrahydrofolic acid (MTHF) and FAD, classifying it as an MTHF-type photolyase. Compared to other MTHF photolyases the absorption maximum of Neurospora photolyase is shifted from ca 380 nm to 391 nm (epsilon = 34,800), while an additional shoulder is present at 465 nm. In dark-adapted enzyme the FAD chromophore is predominantly present in the oxidized form, in contrast with E. coli and Saccharomyces cerevisiae photolyase, which contain mainly semiquinone or fully reduced FAD, respectively. Preillumination or dithionite treatment converted oxidized FAD in Neurospora photolyase into the fully reduced form, with a concomitant shift of the absorption maximum from 391 to 396 nm and disappearance of the 465 nm shoulder. The action spectrum of photoreactivation coincides with the absorption spectrum of preilluminated (reduced) photolyase, extending the spectral region of MTHF-type photolyases from 380 till 396 nm. A quantum yield of 0.57 was obtained for the overall repair reaction. Comparison of spectral properties of FAD in Neurospora photolyase and the model compound lumiflavin points to an apolar microenvironment of photolyase-bound FAD. Neurospora photolyase has distinct advantages over E. coli photolyase as it is more stable and contains a full complement of chromophores.

Deoxyribodipyrimidine Photo-Lyase↗
PubMed1994

Partial radiocarpal arthrodesis.

Eight patients underwent partial radiocarpal arthrodesis for various wrist disorders. There were 5 men and 3 women, whose age at operation ranged from 33 to 59 years with an average of 44 years. The indications for operation included post-traumatic changes secondary to distal radius fracture in 5 cases, Kienböck's disease in 1, Madelung's deformity in 1, and rheumatoid arthritis in 1. Arthrodesis was performed at the radiolunate joint in 5 cases, and at the radioscapholunate joint in 3 cases. In all cases, bone union was obtained within 3 months postoperatively. Postoperative wrist pain disappeared in 6 cases, and decreased in 2 cases. The average postoperative flexion-extension arc of motion was 35 degrees in the radioscapholunate arthrodesis group, and 85 degrees in the radiolunate arthrodesis group. The postoperative grip strength compared with the unaffected hand averaged 51% in the radioscapholunate arthrodesis group, and 68% in the radiolunate arthrodesis group. One patient showed a deterioration in the osteoarthritic change in the midcarpal joint.

Adult↗
PubMed1994

Twin-barrelled vascularized fibular grafting to the pelvis and lower extremity.

From 1988 to 1992, 17 patients were treated for a large bone defect or established nonunion of the pelvis or lower extremities with twin-barrelled vascularized fibular grafts. There were 13 men and four women whose average age at operation was 39 years (range, 13-73 years). The reconstructed site was the pelvis in two patients, the femur in 12, the tibia in two, and the ankle in one. The mean length of the bone defect was 8.5 cm, and the mean length of the harvested fibula was 22 cm. Free grafts were transferred in 14 patients and pedicle grafts in three patients. The mean duration of the operation was six hours 46 minutes (range, 3.5-10.6 hours). Average blood loss was 1949 ml (range, 268-5308 ml). In one patient, the vascularized transfer failed, and recurrence of local infection was encountered in another. In the remaining 15 patients, the postoperative course was uneventful; the mean period to bony union was 5.1 months (range, two to 12 months). The mean time to full weight bearing was four months in pelvic reconstruction, 10.6 months in femoral reconstruction, and 6.3 months in leg reconstruction. Only one patient had a fracture of the fibular graft. This method is well suited for patients with a bone defect up to 13 cm in length of the pelvis or lower extremities.

Adolescent↗
PubMed1993

Vascular complications of vascularized composite tissue transfer: outcome and salvage techniques.

Two hundred fifty-two vascularized composite tissue transfers were performed from 1985 to 1992 at Nara Medical University Hospital. Free tissue transfers were performed in 185 patients and island tissue transfers in 67 patients. Of these, 39 flaps were reexplored because of vascular complications. On initial reexploration, vascular obstruction was found at the site of anastomosis or in the main vascular pedicle in 36 patients and in the perforating vessels to the monitor flap in three patients. Arterial thrombus occurred in 11 patients, venous thrombosis in 12, and both in nine. Twenty-five reexplored flaps were salvaged. Initially, heparin was administered systemically when vascular compromise was suspected intraoperatively or postoperatively. Recently, we have used a "continuous local heparinization" technique to minimize blood loss. This method has been used in 12 patients who underwent reexploration and in nine patients in whom vascular compromise was suspected. Nineteen flaps survived completely, and two flaps failed.

Adolescent↗
PubMed1993

Blood flow through prefabricated flaps--an experimental study in rabbits.

Prefabricated flaps were created by femoral vessel implantation beneath the abdominal skin in rabbits. The area of survival and blood flow through the prefabricated flap were measured after 1, 2, 4, 6, 8, and 12-week intervals. The parameters at 6, 8 and 12-week intervals were significantly larger than those for random pattern flaps (p < 0.01), but were significantly smaller than those for axial pattern flaps (p < 0.01). The minimum interval at which the prefabricated flap could be transferred successfully was between 6 and 8 weeks in this model. Microangiography demonstrated that neovascularisation began at the distal end of the implanted vascular bundle and spread throughout the flap by 8 weeks.

Abdominal Muscles↗
PubMed1993

Vascularized tail bone grafts in rats.

A new experimental model for vascularized corticocancellous bone grafts was established by investigation of vascular anatomy of the tail in 15 adult Fischer 344 rats and determination of the viability of vascularized tail bone grafts into the abdominal wall in 22 7-week-old rats. The tail bones of 40 rats were then raised on the pedicle of the caudal artery and its venae comitantes, transferred to a resected portion in the femur, and observed for 16 weeks. The vascularized graft showed marked reactive periosteal bone formation during the first and second weeks following transfer, and thereafter, the graft continued to show active bone formation. In transverse section, the sharp processes became rounded. In the cancellous bone, both bone resorption and bone formation were noticeably activated early after transfer, although resorption predominated and the amount of the cancellous bone consequently diminished. The nonvascularized grafts showed "creeping substitution." The results suggest that morphologic adaptation occurs if living (i.e., vascularized) tail bones are transferred to long-bone femurs.

Abdominal Muscles↗
PubMed1993

Erythromycin inhibits the production of elastase by Pseudomonas aeruginosa without affecting its proliferation in vitro.

Extracellular proteases from Pseudomonas aeruginosa play important roles in infections in the respiratory tract. The effect of erythromycin (EM), a macrolide antibiotic, on the production of elastase by P. aeruginosa was investigated in vitro and compared with the effect of other antibiotics. Thirty-four (94.4%) of thirty-six different strains produced detectable amounts of elastase determined by the gel diffusion method. The elastase production was inhibited completely by EM in 27 (79.4%) of 34 strains at some concentrations between 0.125 and 64 micrograms/ml. At 4 micrograms/ml or less, the elastase production was inhibited completely in four (11.8%) strains and more than 50% in the other 10 (29.4%). At 8 micrograms/ml or less, the elastase production was inhibited completely in 11 (32.4%) strains and more than 50% in the other nine (26.5%). The proliferation was partially inhibited at 32 and 64 micrograms/ml. Roxithromycin inhibited the elastase production at higher concentrations than EM without inhibiting the proliferation. Midecamycin and ampicillin did not inhibit the elastase production or the proliferation. Doxycycline and ticarcillin inhibited the elastase production and/or the proliferation at concentrations greater than 16 micrograms/ml. Although ofloxacin (OFLX) inhibited both the proliferation and the elastase production in parallel at low concentrations, there were six (16.7%) strains resistant to OFLX. Among them the elastase production was inhibited in five strains by EM. These results suggest that EM acts on P. aeruginosa to inhibit extracellular production of elastase without affecting the proliferation of the bacteria.

Cell Division↗