Search PubMed⌕ Search

Biomedical subjects

K Harii

Publications and source records attributed to K Harii.

At least 37 records · Page 2Linked to original sources
PubMed2000

Microsurgical reconstruction for caustic injuries of the oral cavity and esophagus.

Ingestion of caustic material often produces profound and irreversible pathologic changes that require reconstructive surgery of the organs damaged. This report describes the authors' successful experience with microsurgical techniques that allowed adequate reconstruction in three patients with cicatricial contracture of the oral cavity and esophagus following ingestion of caustic substances. All patients had attempted suicide by ingesting liquid alkali. Patients #1 and #2 complained of limited mouth opening and impaired tongue movement due to oral scar contracture. Contracture release in the first patient resulted in a defect from the anterior border of the mandible to the retromolar region. The defect was resurfaced with a 6 x 12 cm free forearm flap. Release of the scar contracture in the second patient resulted in a long, narrow, tortuous defect that was difficult to cover, even with a forearm flap, and a jejunal segment was microsurgically transferred as a patch graft to reconstruct the defect. Patient #3 had dysphagia due to stricture of the cervical portion of the esophagus. The defect after resection of the cervical portion was reconstructed by free jejunal interposition. Appropriately selected free-flap transfer in each case provided a satisfactory restoration of function of the oropharyngeal and digestive passages.

Adult↗
PubMed2000

Endoscopic-assisted harvest of the temporoparietal fascial flap.

Elevation of the temporoparietal fascial flap by conventional T or Y incisions in the temporal region frequently leaves conspicuous scarring, hair thinning, or baldness. To avoid such undesirable effects, endoscopic-assisted harvest of the temporoparietal fascial flap was performed in 9 patients with microtia. Through two horizontal incisions in the temporal region, the temporoparietal fascia was dissected, and the flap was harvested using bipolar scissors and coagulating shears. Flaps were dissected and harvested successfully without any complications in 7 patients, although extra incisions were required to facilitate coagulation in 2 patients. The authors introduce this harvesting technique and describe some representative cases. Using endoscopic guidance, this is a versatile, safe procedure with minimal morbidity, and is applicable to other reconstructive procedures that require a temporoparietal fascial flap, including the free flap.

Adult↗
PubMed2000

Surgical correction of cryptotia with superiorly based superficial mastoid fascia and skin paddle.

An approach for the correction of cryptotia using a superiorly based superficial mastoid fascial flap and a skin paddle is introduced. The buried portion of the auricle was exposed through an incision made along the upper part of the helix, followed by an appropriate correction of the deformed cartilage. Protrusion of the upper portion of the auricle was accomplished using anchoring sutures. A small skin paddle was elevated from the caudal portion of the auricular sulcus with the superiorly based superficial mastoid fascia as the nutrient pedicle and transferred to the temporal skin defect. The procedure was performed in eight auricles in a total of seven patients with cryptotia. A satisfactory contour and protrusion of the auricle were maintained postoperatively, leaving the scar within the auricular sulcus.

Adolescent↗
PubMed2000

Experience with a strong bleaching treatment for skin hyperpigmentation in Orientals.

Although a variety of topical treatments have been used for skin hyperpigmentation, the effectiveness of each varies after prolonged treatment. In this study, 136 Oriental patients who were followed up for more than 12 weeks were analyzed. The treatment protocol was composed of two steps: bleaching (2 to 6 weeks) and healing (2 to 6 weeks); 0.1% to 0.4% all-trans retinoic acid aqueous gel was originally prepared and applied concomitantly with hydroquinone-lactic acid ointment for bleaching. After obtaining sufficient improvement of the hyperpigmentation, a corticosteroid was applied topically with hydroquinone and ascorbic acid for healing. Improvement was evaluated with a narrow-band reflectance spectrophotometer. The results were successful in more than 80 percent of cases of senile lentigines and postinflammatory hyperpigmentations, especially on the face. Sixty percent of cases of nevus spilus were also successfully treated. Although the transient adverse effects of this treatment may be more severe than conventional treatment, this strong bleaching protocol improves a variety of hyperpigmented lesions, including nevus spilus, with a higher success rate and a shorter treatment period than conventional protocols.

Administration, Topical↗
PubMed2000

Anterolateral thigh flap donor-site complications and morbidity.

The authors examined donor-site complications and morbidity in 37 patients after reconstruction with free or pedicled anterolateral thigh flaps. Intraoperative assessment included damage to the vastus lateralis muscle and whether the main pedicle of the rectus femoris muscle had been killed. Postoperative assessment of the donor site included wound healing, range of motion, muscle strength, gait, and sensation. Patients were surveyed with a questionnaire about fatigue in their activities of daily life and the appearance of the donor site. All 32 patients who underwent primary skin closure could perform activities of daily life normally, and most (87.5 percent) reported that donor-site appearance was satisfactory. However, the severity of donor-site dysfunction was related to the degree of damage to the vastus lateralis muscle, and most patients (87.5 percent) had some loss of sensation at the anterolateral aspect of the thigh. Because of adhesions between the meshed skin graft and the underlying fascia, range of motion at the hip and knee was limited in significantly more patients who had received split-thickness skin grafts (60 percent) than patients who had undergone primary skin closure (3.1 percent). Therefore, wider flaps or flaps harvested nearer the knee may increase donor-site morbidity. The authors concluded that the incidence of long-term morbidity with the anterolateral thigh flap is low, although it is increased when the flap includes the vastus lateralis muscle or is wider and requires additional skin grafting at the donor site.

Adult↗
PubMed2000

Postoperative complications and functional results after total glossectomy with microvascular reconstruction.

Microsurgical reconstruction after total glossectomy can greatly improve quality of life; however, postoperative functional results are often unstable, and the effectiveness of total glossectomy remains questionable. To determine the problems of reconstruction after total glossectomy with laryngeal preservation and to examine the functional results of swallowing and speech, 30 patients who had undergone total glossectomy and reconstruction with free flaps were reviewed for this study. The patients ranged in age from 20 to 73 years, and 23 of the 30 had undergone reconstruction with a rectus abdominis musculocutaneous flap. Wider and thicker flaps were designed and transferred and were sutured to suspend the larynx. To maintain physiologic swallowing function after surgery, the extent of laryngeal suspension and cricopharyngeal myotomy was limited. Of the 30 patients, 21 (70 percent) could be decannulated with laryngeal preservation; 20 of these 21 could tolerate a normal/soft/pureed diet, and 1 was limited to a fluid diet. Speech was intelligible in 16 of the 19 patients evaluated. In 9 of the 30 patients, laryngeal function could not be preserved. In four of these nine patients, additional resection combined with total glossectomy caused severe aspiration and recurrent pneumonia. Two patients with preoperative cerebral dysfunction were also poor candidates for laryngeal preservation. Additionally, the transferred flap's lack of bulk in the oral cavity and the advanced age (73 years) of one patient and the poor motivation of another may have contributed to postoperative aspiration. Aspiration occurred in one patient because of local recurrence of a tumor. The presence of preoperative cerebral dysfunction (p = 0.025), resection of the epiglottis (p = 0.005), and postoperative orocutaneous fistulas (p = 0.04) were significantly associated with the failure of laryngeal preservation. However, because of the difficulty of enrolling a sufficient number of patients in the study and the inherent limitations of retrospective studies, multivariate analysis in this study showed that no factors, such as patient age, flap volume, and the type of neck dissection, were significant predictors of laryngeal preservation. Although prospective studies are necessary, the function of individual patients must be assessed so that the study experiences discussed here can be applied to subsequent patients.

Adult↗
PubMed1999

Cloning and expression of a novel galactoside beta1, 3-glucuronyltransferase involved in the biosynthesis of HNK-1 epitope.

We isolated a cDNA encoding a novel glucuronyltransferase, designated GlcAT-D, involved in the biosynthesis of the HNK-1 carbohydrate epitope from rat embryo cDNA by the degenerate polymerase chain reaction method. The new cDNA sequence revealed an open reading frame coding for a protein of 324 amino acids with type II transmembrane protein topology. The amino acid sequence of GlcAT-D displayed 50.0% identity to rat GlcAT-P, which is involved in the biosynthesis of the HNK-1 epitope on glycoproteins. Expression of GlcAT-D in COS-7 cells resulted in the formation of the HNK-1 epitope on the cell surface. The enzyme expressed in COS-7 cells transferred a glucuronic acid (GlcA) not only to asialo-orosomucoid, a glycoprotein bearing terminal N-acetyllactosamine structure, but also to paragloboside (lacto-N-neotetraosylceramide), a precursor of the HNK-1 epitope on glycolipids. Furthermore, substrate specificity analysis using a soluble chimeric form of GlcAT-D revealed that GlcAT-D transfers a GlcA not only to Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc-pyridylamine++ + but also to Galbeta1-3GlcNAcbeta1-3Galbeta1-4Glc-pyridylamine++ +. Enzymatic hydrolysis and Smith degradation of the reaction product indicated that GlcAT-D transfers a GlcA through a beta1,3-linkage to a terminal galactose. The GlcAT-D transcripts were detected in embryonic, postnatal, and adult rat brain. In situ hybridization analysis revealed that the expression pattern of GlcAT-D transcript in embryo is similar to that of GlcAT-P, but distinct expression of GlcAT-D was observed in the embryonic pallidum and retina. Regions that expressed GlcAT-D and/or GlcAT-P were always HNK-1-positive, indicating that both GlcATs are involved in the synthesis of the HNK-1 epitope in vivo.

Amino Acid Sequence↗
PubMed1999

The novel sphingosine 1-phosphate receptor AGR16 is coupled via pertussis toxin-sensitive and -insensitive G-proteins to multiple signalling pathways.

In the present study, we determined the agonist specificity and the signalling mechanisms of a putative sphingosine 1-phosphate (S1P) receptor, AGR16. In CHO cells transiently transfected with an AGR16 expression vector, but not in cells transfected with an empty vector, the addition of a low concentration of S1P (1 nM) caused an increase in the intracellular free Ca2+ concentration ([Ca2+]i) by mobilization of Ca2+ from both intra- and extra-cellular pools. To determine the spectrum of agonists for AGR16, we employed K562 cells, which in the naive state do not respond at all to either S1P or structurally related lipids with an increase in [Ca2+]i. In K562 cells stably expressing AGR16, S1P and sphingosylphosphorylcholine (SPC) dose-dependently increased [Ca2+]i with half-maximal values of 3 nM and 100 nM respectively. In CHO cells stably expressing AGR16 (CHO-AGR16), but not in parental CHO cells, we observed specific binding of [32P]S1P, which was displaced by unlabelled S1P and SPC. In CHO-AGR16 cells, but not in parental CHO cells, S1P stimulated the production of inositol phosphates and Ca2+ mobilization which was only 30% inhibited by pertussis toxin (PTX), different from the case of the recently identified S1P receptor EDG1. Also in CHO-AGR16 cells, but not in CHO cells, S1P at higher concentrations activated mitogen-activated protein kinase (MAPK) in a PTX-sensitive and Ras-dependent manner. S1P also induced the activation of two stress-activated MAPKs, c-Jun N-terminal kinase and p38, in a manner that was totally insensitive to PTX. In CHO-AGR16 cells, S1P induced stress-fibre formation, with an increase in myosin light chain phosphorylation, in a PTX-insensitive and Rho-dependent manner. S1P also induced an increase in the cellular cAMP content in CHO-AGR16 cells, which contrasts sharply with the case of EDG1. These results establish that the S1P receptor AGR16 is coupled via both PTX-sensitive and -insensitive G-proteins to multiple effector pathways.

Animals↗
PubMed1999

A regenerative change during muscle adaptation to denervation in rats.

The purpose of this study is to examine the cellular and molecular events coincident with muscle denervation, especially the regenerative changes seen following muscle denervation, the role of satellite cells in this process, and the possibility of apoptotic degeneration of myonuclei as a mechanism of myonuclei loss during muscle denervation atrophy. Myosin heavy chain (MHC) isoform expression during muscle denervation was examined using pyrophosphate acrylamide gel electrophoresis and immunohistochemistry. DNA fragmentation (apoptosis) in myonuclei of denervated fibers was investigated using agarose gel electrophoresis, the TUNEL technique and ELISA for cytoplasmic histone-associated DNA fragmentation. Immunohistochemistry for MyoD and BrdU was also performed. Following muscle denervation, embryonic MHC, which is not expressed in adult healthy muscles, was expressed in some denervated fibers as well as in small activated satellite cells; maximal expression was observed 2 to 3 weeks after denervation. Activation and proliferation of satellite cells were observed, while few typical regenerating fibers were identified. It is speculated that most activated satellite cells fused to the denervated maternal fibers in order to repair them instead of fusing to each other to form new fibers as a mechanism that compensates for the atrophic changes after denervation. Although DNA ladder formation was not observed with agarose gel electrophoresis, DNA fragmentation was detected by the TUNEL technique and ELISA, suggesting that apoptotic degeneration contributes to the loss of myonuclei associated with denervation atrophy.

Animals↗
PubMed1999

Evaluation of flow characteristics of soft-tissue vascular malformations using technetium-99m labelled red blood cells.

The estimation of intralesional haemodynamics is crucial in determining appropriate treatment for soft-tissue vascular malformations. The aim of this study was to develop a method to evaluate the flow characteristics of soft-tissue vascular malformations using technetium-99m labelled red blood cells (99mTc-RBCs). Seventy-nine soft-tissue vascular malformations, including 20 arteriovenous malformations and 59 venous malformations, in 57 patients were examined. Following the intravenous injection of 99mTc-RBCs, dynamic imaging was performed for 30 min with the lesion in the field of view (99mTc-RBC flow study). A time-activity curve was generated for the lesion, and the lesion was categorized as a high-flow or low-flow lesion by visual inspection of the curve. In low-flow lesions, mean vascular transit time (MTT) was calculated by curve fitting based on a two-compartment model. Twenty-nine lesions in 19 patients were examined twice, and reproducibility was assessed. In 23 venous malformations in 16 patients, 99mTc-Sn colloid was percutaneously injected into the intravascular space of the lesion, and dynamic data of 5-min duration were acquired (direct puncture scintigraphy). MTT was estimated from the washout curve and compared with MTT estimated by 99mTc-RBC flow study. 99mTc-RBC flow study classified all 20 arteriovenous malformations as high-flow lesions and all 59 venous malformations as low-flow lesions. In the low-flow lesions, MTT estimated by 99mTc-RBC flow study ranged from 61.2 to 2174.9 s. In the reproducibility study, complete concordance in classification and high correlation in MTT were shown between the first and second examinations. MTT estimated by 99mTc-RBC flow study was significantly correlated with that estimated by direct puncture scintigraphy. In summary, 99mTc-RBC flow study provides a quantitative indicator of intralesional haemodynamics in low-flow lesions in addition to accurate distinction between high-flow and low-flow lesions. The results of this study suggest the feasibility of detailed evaluation of flow characteristics in soft-tissue vascular malformations using 99mTc-RBCs.

Adolescent↗
PubMed1999

Free adipofascial flap for scalp reconstruction: case report.

The authors describe a case in which a large defect of the scalp was present after tumor excision. It was covered with a free adipofascial flap and a split-thickness skin graft, with satisfactory results. Numerous similar cases of scalp defects reconstructed with other free flaps have been described. But since donor-site morbidity is minimized with free adipofascial flaps, they should be used more often for reconstruction of scalp defects.

Adipose Tissue↗
PubMed1999

Evaluation of muscle graft using facial nerve on the affected side as a motor source in the treatment of facial paralysis.

To acquire symmetry of the cheek when smiling, we carried out 39 free vascularised grafts of the muscle, the motor nerve of which was sutured to a stump of the ipsilateral facial nerve, for 39 patients with facial paralysis. We used two methods: an as healthy and fresh as possible facial nerve stump (method 1A, n = 17), or an incompletely affected stump (method 1B, n = 22). The results are classified into grade 1 to 5 indicating increasing efficiency of muscle function. All patients who had method 1A and 14 patients who had method 1B were evaluated grade 4 or better. Both an incompletely affected facial nerve stump and the proximal stump of a facial nerve that had previously been resected have sufficient function to provide contraction in the grafted muscle.

Adult↗
PubMed1999

Multi-bracket appliance in management of mandibular reconstruction with vascularized bone graft.

BACKGROUND: The most commonly used tool for maxillo-mandibular fixation to the patient who underwent reconstruction using a vascularized bone graft after mandibular resection is a dental arch-bar. However, the occlusal relationship achieved by this method is not ideal. Different from the dental arch-bar, the multi-bracket appliance which is frequently used in orthodontic treatment can control the position of each individual tooth three dimensionally. Thus, this appliance was applied for maxillo-mandibular fixation to patients who underwent mandibular reconstruction using a vascularized bone graft. METHODS: A multi-bracket appliance was applied to three patients. Prior to the surgery, standard edgewise brackets were bonded to the teeth in the maxilla and in the remaining mandible. After mandibular resection, wires for maxillo-mandibular fixation were applied. The harvested bone was then carefully fixed with miniplates to maintain the occlusion. The multi-bracket appliance was worn for 3 months when the wound contraction became mild. RESULTS: All three cases demonstrated stable and good occlusion. They also demonstrated satisfactory post-surgical facial appearance. CONCLUSIONS: Compared to conventional dental arch-bars, a multi-bracket appliance offers improved management of mandibular reconstruction. Firstly, its properties are helpful in maintaining occlusion of the remaining dentition accurately in bone grafting procedure as well as protecting against postsurgical wound contraction. Secondly, the multi-bracket appliance keeps the oral cavity clean without periodontal injury. As a result, stable occlusion of the residual teeth and good facial appearance were obtained.

Adolescent↗
PubMed1999

Free jejunal patch to reconstruct oral scar contracture following caustic ingestion.

Reconstruction of oral scar contracture is often a challenging problem due to the complex structures and functions of the oral cavity. This report describes the treatment of a patient who sustained extensive oral scar contracture following caustic liquid soda ingestion. Surgical release of the scar contracture formed an S-shaped, thin, long defect that was difficult to cover with a conventional flap or skin graft. A jejunal segment was transferred microsurgically as a patch to reconstruct the defect. It sustained a sufficient oral space to provide full opening of the mouth and good movement of the tongue. A free jejunal flap, used occasionally for reconstruction following oral cancer resection, has significant advantages for restoration of function after release of an oral scar contracture.

Burns, Chemical↗
PubMed1999

Prefabricated free jejunal transfer: a new reconstructive technique for high pharyngeal defects.

A new method that uses a prefabricated free jejunal transfer has been applied to three cancer patients with pharyngoesophageal defects with a high pharyngeal deficit extending up to the nasopharynx. In this method, the jejunum harvested in the usual manner is divided into two segments with a single vascular pedicle. Its distal segment is used to reconstruct the cervical esophagus, and its proximal segment is turned over to create a mucosal patch to cover the high pharyngeal defects. The two segments are then co-apted in a side-by-side anastomosis. The esophagus can be reconstructed in a naturally straight shape without a curved portion or blind loop formation, thus leading to good swallowing function. In our series, all grafts survived well and there was no complication directly related to jejunal transfer. All patients could tolerate a soft diet without difficulty. This method is easy to perform and applicable to any shape or size of very high pharyngeal defects that cannot be reconstructed properly by other methods. Although patients with an advanced hypopharyngeal cancer usually have a poor prognosis, this technique allows a better quality of life for a probable short life span.

Aged↗
PubMed1999

Anterolateral thigh flap for abdominal wall reconstruction.

The free or pedicled anterolateral thigh flap was introduced for the reconstruction of large abdominal wall defects. This flap is superior to the tensor fasciae latae musculocutaneous flap in several respects. These include the wide, reliable skin territory (which can reach the level of the knee) and the long pedicle. Therefore, a pedicled anterolateral thigh flap with reliable blood circulation can easily be positioned above the umbilicus. In addition, the free anterolateral thigh flap has greater freedom of orientation and can be used to repair larger abdominal wall defects than can the tensor fasciae latae flap. Seven patients in whom abdominal wall defects had been reconstructed with pedicled or free anterolateral thigh flaps were reviewed. Their average age was 47.1 years (range, 21 to 74 years), and the average follow-up period was 10.7 months (range, 2 to 21 months). The size of the abdominal wall defects ranged from 12 x 12 cm to 18 x 24 cm, and the size of the transferred flap ranged from 10 x 20 cm to 20 x 20 cm. Three flaps were pedicled and four were free, of which three incorporated the tensor fasciae latae flap. All flaps survived completely, and no postoperative abdominal hernias developed. Despite some variations in vascular anatomy and technical difficulties in elevating the anterolateral thigh flap, the authors conclude that the pedicled or free anterolateral thigh flap is superior to the tensor fasciae latae flap for reconstruction of large abdominal wall defects.

Abdominal Muscles↗