Biomedical subjects

A Hayashi

Publications and source records attributed to A Hayashi.

At least 109 records · Page 6Linked to original sources

PubMed1999

Analysis of vitrectomy for idiopathic macular hole by optical coherence tomography.

PURPOSE: To evaluate foveal structure after vitrectomy for idiopathic macular hole in relation to postoperative visual outcome. METHODS: Optical coherence tomography was performed postoperatively to assess retinal thickness at the foveal center in patients who underwent vitrectomy, posterior hyaloid membrane removal, and perfluoropropane gas tamponade for idiopathic macular hole. Thirty-seven eyes of 36 patients documented to have achieved anatomic hole closure by optical coherence tomography were included in the study. RESULTS: Increased visual acuity significantly correlated with greater foveal thickness assessed at a median of 5 months postoperatively (Spearman analysis; R = .453, P = .005). CONCLUSION: Visual outcome after anatomic closure of macular holes by vitrectomy is closely related to the structure of the center of the fovea postoperatively.

Aged↗

PubMed1999

Recurrence and survival after surgical management of rectal cancer.

BACKGROUND: Reported local recurrence rates for rectal cancer are significantly reduced using a combination of superior surgical technique, in the form of total mesorectal excision, and routine radiotherapy. In an attempt to determine the effectiveness of current local management strategies, a review of Vancouver Island Cancer Centre patients with rectal cancer was performed and the overall local recurrence rate was identified. METHODS: We retrospectively reviewed the charts of 272 rectal cancer patients from 1988 to 1998. Two hundred and twenty-nine patients met inclusion criteria. Analysis of patient factors included age, gender, type of surgery, and adjuvant therapy. Tumors were assessed for level, stage, and grade. Local recurrence and distant metastases were also documented. Variables influencing local recurrence in this group were identified and disease-free and actuarial survival determined. RESULTS: Of 229 patients analyzed, 12.7% (29) had local recurrences. Variables influencing local recurrence were number of positive lymph nodes, vascular invasion, and neural invasion. There was no significant difference in local recurrence between patients having anterior resection and those having abdominoperineal resection. None of the patients who received preoperative radiotherapy had a local recurrence. Actuarial disease-free survival was 87% at 5 years. CONCLUSIONS: Limiting local recurrence is one of the most important goals in the treatment of rectal cancer. It is essential to identify those patients with "high risk" tumors as identified by endorectal ultrasound or pathologic features. These patients comprise the group most likely to benefit from a routine mesorectal excision combined with adjuvant radiotherapy.

Aged↗

PubMed1999

Analysis of 1,992 patients with anorectal malformations over the past two decades in Japan. Steering Committee of Japanese Study Group of Anorectal Anomalies.

BACKGROUND/PURPOSE: This report describes the results of a group study of the Japanese Study Group of Anorectal Anomolies (JSGA) to determine the relative incidence of specific types of anorectal anomaly in Japan, and includes discussion of rectourethral fistula regarding the relationship between the levels of the fistula and blind end of the rectum, low type deformity, rare types, and associated anomalies. METHODS: A total of 1,992 patients (1,183 boys and 809 girls) registered from 1976 to 1995 were analyzed. RESULTS: High-type deformities accounted for 26.0% of cases, intermediate 10.7%, low 57.2%, miscellaneous 4.5% and unclassified 1.8%. The most frequent deformity was male anocutaneous fistula (n = 364), followed by male rectourethral fistula (n = 333), and female anovestibular fistula (n = 241). There were 42 rectovesical fistulas in boys and 93 rectocloacal fistulas in girls. Covered anus complete occurred at the same frequency (10.1% of low deformities) as covered anal stenosis. In rectourethral fistula, the blind end of the rectum lay at or above the level of the P-C line in 40.3% of cases, at or above the M line in 39.6% and at the vicinity of the I line in 20.2%, respectively. There was no parallel relationship between the site of the fistula opening and the level of the rectal pouch. The overall incidence of patients having one or more associated anomalies was 45.2%: 70.6% in high deformity, 60.7% in intermediate, and 31.3% in low. The rate of association of Down's syndrome with deformities without fistula (40.3%) was significantly higher than with deformities with fistula (0.3%). CONCLUSIONS: Rectovesical fistula and covered anus complete were not infrequent deformities in this series. We consider that at least 20% of rectourethral fistula should be categorized as intermediate or low deformity from the viewpoint of the position of the rectal pouch. A significant preponderance of Down's syndrome in the deformities without fistula suggests that further investigation of associated anomalies in comparision with other congenital diseases may provide insights into the pathogenesis of anorectal malformation in the field of molecular genetics.

Anal Canal↗

PubMed1999

Nonvitrectomizing vitreous surgery: a strategy to prevent postoperative nuclear sclerosis.

OBJECTIVE: The development or progression of postoperative nuclear sclerosis is the most common complication of successful vitrectomy in elderly patients. The authors treated idiopathic epimacular proliferation (EMP) with nonvitrectomizing vitreous surgery in an attempt to prevent postoperative nuclear sclerosis. DESIGN: Prospective, nonrandomized, comparative case series. PARTICIPANTS: The authors surgically removed membranes from the sensory retina in 21 eyes of 21 patients with EMP. INTERVENTION: Neither intravitreal infusion nor vitrectomy of any kind was performed during the procedure. The peeled membrane was left floating in the vitreous cavity in 11 (group 1) eyes and removed in 10 eyes (group 2). Nonoperated fellow eyes served as controls. MAIN OUTCOME MEASURES: Visual acuity, slit-lamp and/or Scheimpflug photography, and refractometry were performed pre- and postoperatively to evaluate changes in the degree of lenticular opacity. RESULTS: There was no difference in the rate of development or progression of nuclear sclerosis or the degree of myopic shift between operated and control eyes during the postoperative follow-up period (mean, 9.7 months). No serious complications were noted. There was no difference in postoperative course between patients in the two operative groups. CONCLUSIONS: Although interpretation of the results of this study is limited due to its small size and short follow-up, nonvitrectomizing vitreous surgery seems to decrease the postoperative development or progression of nuclear sclerosis in patients with idiopathic EMP.

Aged↗

PubMed1999

Association between polymorphism of the cholecystokinin gene and idiopathic Parkinson's disease.

Parkinson's disease (PD) is characterized by major alterations of neurotransmitter activity due to damage of the substantia nigra. Changes in neuropeptide concentration within the basal ganglia may play an important role in the putative dopaminergic-peptidergic interactions associated with the disease. Cholecystokinin (CCK) modulates the release of dopamine in the mesolimbic pathway and affects dopamine-related behavior. We analyzed genetic variations in the CCK gene, in both the coding and promoter region, in order to investigate the role of polymorphism in idiopathic PD. Four polymorphic sites of the CCK gene (-196G/A, -45C/T, 1270C/G, 6662C/T) were found in PD patients and controls. Complete linkage disequilibrium was observed between the -45 locus and the 1270 locus, and also a possible linkage disequilibrium was found between the -45 and -196 loci. A significant difference was found in the distributions of three identified genotypes at the -45 locus between 116 PD patients and 95 age-matched control subjects (chi2 = 7.95, p = 0.018, Bonferroni correction; p = 0.054). In addition, a significant difference was obtained amongst the three genotypic groups at the -45 locus when compared between PD patients who experienced hallucinations (n = 23) and those (n = 93) who did not (chi2 = 8.08, p = 0.018, Bonferroni correction, p = 0.126). Our data suggested that mutations at the -45 locus in the promoter region of the CCK gene may influence vulnerability to hallucinations in PD patients treated with L-dopa.

Age of Onset↗

PubMed1999

Alterations in protein tyrosine kinase pathways following retinal vein occlusion in the rat.

PURPOSE: To determine whether an experimental retinal vein occlusion in the rat activates protein tyrosine kinase pathways and increases angiogenic growth factors in the retina. METHODS: Retinal vein occlusion (RVO) was induced in the rat retina with argon laser photocoagulation. Retinas were collected at 2 days, 1, 2, and 4 weeks after RVO and divided into halves: one half represented an area within the distribution of the occluded vein [RVO(IN)] and the other half represented an area outside the distribution of the occluded vein [RVO(OUT)]. RVO(IN) and (OUT) were examined by western blot analysis of tyrosine-phosphorylated proteins, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and 3 signal proteins in the tyrosine kinase pathways: phospholipase Cgamma (PLCgamma), phosphatidylinositol 3-kinase (PI3K), and mitogen-activated protein kinase (MAPK). RESULTS: RVO caused a severe capillary nonperfusion in RVO(IN). Overall tyrosine-phosphorylated proteins were increased after RVO, especially in RVO(IN) at 2 days and 1 week. VEGF and bFGF were markedly increased in RVO(IN) at 2 days and 1 week. Tyrosine-phosphorylated PLCgamma, PI3K, and MAPK were also increased in RVO(IN) at these time points. CONCLUSIONS: RVO caused an increase in overall protein tyrosine phosphorylation in the rat retina. This increase was associated with an increase in angiogenic growth factors (VEGF and bFGF). These results suggest that protein tyrosine kinase pathways are activated during retinal ischemia and may play a role in mitogenesis of vascular endothelial cells and other responses in the retina after RVO.

Animals↗

PubMed1999

Lateral calcaneal V-Y advancement flap for repair of posterior heel defects.

We obtained favorable results in reconstruction of the posterior heel with a lateral calcaneal V-Y advancement flap. This technique simplifies the operative procedure and eliminates the disadvantages of the original lateral calcaneal flap and its island version while retaining the advantages of these methods.

Aged↗

PubMed1999

Improvement of dysgeusia after thymectomy with thymoma.

We present a case of 39-year-old woman with thymoma complaining of dysgeusia. This patient had suffered from dysgeusia for the previous 6 months. Thymectomy with the thymoma was performed, and her dysgeusia was improved within 6 months after the operation. The anti-acetylcholine-receptor antibody was reduced from 0.9 nmol/l to 0.4 nmol/l (normal: below 0.6 nmol/l) by the surgical intervention. This case suggested that symptoms of dysgeusia can be associated with myasthenic status.

Adult↗

PubMed1999

Experimental and clinical evaluation of the harmonic scalpel in thoracic surgery.

The Harmonic Scalpel is an ultrasonic instrument for cutting and coagulating tissue. We are reporting our evaluation of the Harmonic Scalpel safety and efficacy in both experimental and clinical thoracic surgery. First, we confirmed the safety in thoracic surgery by following two preliminary studies using the Harmonic Scalpel. 1: Pulmonary parenchyma was incised using "Coagulating Shears" to evaluate hemostasis and air leakage. 2: Pulmonary hilar vessels were contacted directly with "Dissecting Hook" blade at optimum cutting power mode to evaluate potential vascular wall injury by the Harmonic Scalpel. Subsequently, the Harmonic Scalpel was used for a partial lung resection due to metastatic lung cancer. Particular application was for a chest wall incision, interlobar separation of the lung, and dissection of a pulmonary artery, in lung cancer operations. We concluded that cutting and hemostasis of pulmonary parenchyma could be achieved with minimal tissue damage using the Harmonic Scalpel. Compared to electric coagulation, the Harmonic Scalpel minimizes tissue charring and dissection, and eliminates thermal injury in thoracic surgery.

Animals↗

PubMed1999

Effects of angiotensin I-converting enzyme inhibitor from Ashitaba (Angelica keiskei) on blood pressure of spontaneously hypertensive rats.

The inhibitory activity of angiotensin I-converting enzyme (ACE) was extracted with 80% ethanol from the leaves of Ashitaba (Angelica keiskei). The present ACE inhibitor was fractionated and separated with various chromatographies. The antihypertensive effects of the sample (G fraction) from Ashitaba on spontaneously hypertensive rats (SHR) were observed by long-term administration for 10 wk. Another sample (S fraction) from Ashitaba also had antihypertensive effects after a single intravenous administration to SHR. The sample was further purified by using several chromatographies. The ACE inhibitor fraction was characterized as follows: no significant absorbance, a zwitterion, a water-soluble substance and a positive ninhydrin reaction. According to a mass spectrum analysis, the molecular weight of the ACE inhibitor was determined to be 303 and Na-salt ions of carboxyl groups were detected. The ACE inhibitor from Ashitaba contained in the anti-hypertensive fraction was speculated to be very similar to authentic nicotianamine based on a comparative study of inhibitory activity, mass spectrum analysis and thin-layer chromatographies.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1999

Inhibition of choriocapillaris regeneration with genistein.

PURPOSE: To test the effects of genistein on choriocapillaris regeneration and retinal pigment epithelial (RPE) wound healing in a surgical model in the rabbit. METHODS: Intravitreal injections of either 0.1 ml of a 90-microM concentration of genistein, dimethyl sulfoxide (DMSO; negative control), or 2 microg cycloheximide (positive control) were given 24 hours before surgical debridement of RPE in rabbits. Scanning electron microscopy (EM) of choroidal vascular casts and the RPE wounds and histologic evaluation by light microscopy and EM of the disturbed areas were performed at days 1, 7, and 30 after surgery. Quantitative analysis of the area of the choriocapillaris bed and RPE was performed by automated image analysis, and the results were analyzed by paired Student's t-test. RESULTS: Loss of RPE caused a rapid initial atrophy followed by slower subsequent revascularization of the choriocapillaris, which paralleled the RPE wound healing. Choriocapillaris regeneration appeared nearly normal by day 30 in the DMSO group. Inhibition of choriocapillaris revascularization by genistein was significant at day 30 when compared with the DMSO-treated negative control (P = 0.013). There was a strong trend toward inhibition in the cycloheximide-treated positive control group (P = 0.062), which reached significance at day 7 compared with the DMSO group (P = 0.02). RPE covered the wound area by day 7 in all groups. CONCLUSIONS: Intravitreal injection of genistein was found to cause significant inhibition of choriocapillaris regeneration without apparent effect on RPE wound healing. Tyrosine kinase inhibitors such as genistein may be useful as a pharmacologic approach in the treatment of choroidal neovascularization.

Animals↗

PubMed1999

[A case of delayed cerebral infarction occurring in puerperium preceded by herpes zoster ophthalmicus in late pregnancy].

Delayed central neurological symptoms following herpes zoster ophthalmicus (HZO) such as "herpes zoster ophthalmicus and delayed contralateral hemiparesis" are considered to be due to ipsilateral intracranial vasculopathy. We experienced a rare case with cerebral infarction occurred in puerperium following HZO in late pregnancy. A healthy 30-year-old woman had left HZO at weeks 35 of gestation. She was given acyclovir (ACV) for external use and improved with small pigmentation on the left eye-lid. Seven weeks after the onset of HZO, she suddenly developed aphasia and right hemiparesis. Cerebral angiogram showed narrowing on M 1 segment of the ipsilateral middle cerebral artery. The occlusion was seen on peripheral portion of the angular artery on the same side. In cerebrospinal fluid (CSF), cell count was slightly elevated, but concentration of protein and sugar were normal. Varicella-zoster titer was increased in both serum and CSF. She was treated with intravenous ACV (1500 mg/day) for 10 days. On the next day after the treatment, the cell count was normalized and on 18th day, varicella-zoster titer was decreased in CSF. Higher brain function improved and no relapses occurred. This is a first case of delayed cerebral infarction occurring in puerperium preceded by herpes zoster ophthalmicus in late pregnancy, as far as we searched. We should treat carefully pregnant or lactating patients with HZO, considering delayed cerebral infarction.

Acyclovir↗

PubMed1999

[A case of hypocomplementemic mesangial proliferative glomerulonephritis progressing to focal membranoproliferation without aggravation of urinalysis].

We reported a 14-year-old boy with hypocomplementemic mesangial proliferative glomerulonephritis progressing to focal membranoproliferation without aggravation of urinalysis. He was pointed out as having asymptomatic hematuria by a school urinalysis screening, and revealed mild hematuria and proteinuria (not nephrotic). The laboratory data showed severe hypocomplementemia and high titers of antistreptolysin O (ASO) and antistreptokinase (ASK). A renal biopsy specimen obtained 2 months after the onset showed diffuse mesangial proliferation, and did not display any characteristic changes in membranoproliferative glomerulonephritis by either light or electron microscopy. After eight months of observation, a second renal biopsy was performed in order to examine morphological changes, because severe hypocomplementemia, mild hematuria and proteinuria had persisted. The second biopsy specimen showed C3 deposition with a mesangiocapillary pattern detected by immunofluorescence microscopy and diffuse mesangial proliferation by light microscopy. In some glomeruli, electron microscopy showed focal mesangial interposition, which was considered to be a histological feature of focal membranoproliferative glomerulonephritis. Intravenous methylprednisolone pulse therapy and subsequent glucocorticoid administration (60 mg of prednisolone every other day) was performed. The serum complement level was elevated just after the methylprednisolone pulse therapy, but fell to the previous value within 2 months. The hypocomplementemia, even if proteinuria and hematuria were mild, indicated the existence of glomerular change in this case.

Adolescent↗

PubMed1999

[Effect of intravenous immunoglobulin therapy in a case of idiopathic recurrent brachial and lumbosacral plexopathy].

We report a case of a 23-year-old woman with idiopathic brachial and lumbosacral plexopathy who presented a relapsing course of weakness and numbness following acute onset of pain in the right shoulder or pelvic girdle area. On her first admission, the patient recovered gradually with oral prednisolone. But after about 1 year, her symptoms worsened. In the second admission, oral prednisolone had no effect on her symptoms, so intravenous immunoglobulin (IVIG; 0.1 g/kg/day, 5 days) therapy was tried. The patient improved about 2 weeks after IVIG therapy. About 1 year later, her symptoms worsened and was administered again. In the third admission, IVIG therapy of which dose was the same as that in the previous admission had an effect on her symptoms. The dose of IVIG in our case was relatively low, compared with those in cases reported before (0.2-2 g/kg/day). This findings suggest that a relatively low-dose IVIG therapy is effective for idiopathic plexopathy.

Adult↗

PubMed1999

A combination of autoimmune hepatitis, sensory-dominant peripheral neuropathy, and primary Sjögren's syndrome in the same patient: a rare association.

Although autoimmune hepatitis and sensory-dominant neuropathy have been known to independently accompany primary Sjögren's syndrome, the combination of all these conditions in the same patient has not been described. We report the case of a woman who initially suffered from autoimmune hepatitis and later was diagnosed with primary Sjogren's syndrome upon the development of sensory-dominant neuropathy. In this patient, autoimmune hepatitis preceded neuropathy by one year. All of the diagnoses were confirmed by histological examinations of the liver, sural nerve, and minor salivary gland. Her autoimmune hepatitis was relieved with conservative treatment, and her sensory-dominant neuropathy was alleviated by prednisolone therapy. Our case indicated that the multiple organ involvement, especially that in the liver and peripheral nerves, should be taken into account in the course of primary Sjögren's syndrome.

Anti-Infective Agents↗

PubMed1999

[A case of stiff-man syndrome with head retraction like reflex myoclonus and jerky myoclonus of bilateral lower extremities which responded well to removal of mediastinal carcinoma].

A 58-year-old male presented with reflex myoclonus and stiffness of the left facial, tongue, shoulder, and lower limbs muscles. Muscle stiffness and gait progressively worsened, leading to frequent falls. Acoustic and cutaneous stimuli of head precipitated reflex myoclonus like head retraction. Cutaneous of lower extremities precipitated jerky myoclonus of bilateral lower extremities. CSF analysis were unremarkable. No anti GAD antibody or anti amphiphysin antibody was detected in the serum and CSF. On surface EMG the spasms initiated with 4-5 short burst discharges at intervals between 59 and 84 ms, followed by a tonic decrescendo activity up to 3 s. After diazepam treatment, stiffness and reflex myoclonus of lower extremities were disappeared and head retraction like reflex myoclonus was improved but remained. CT of the chest revealed a mediastinal tumor. Biopsy of the tumor revealed undifferential carcinoma. The patient further improved after the resection of the tumor. These findings suggest that this stiff-man syndrome may occur as an autoimmune paraneoplastic syndrome of CNS.

Autoimmunity↗

PubMed1999

Double filtration plasma exchange and immunoadsorption therapy in a case of stiff-man syndrome with negative anti-GAD antibody.

We report the effects of double filtration plasma exchange and immunoadsorption therapy which were performed for a case of stiff-man syndrome even though the patient was negative for anti-glutamic acid decarboxylase (GAD) antibody. The patient underwent a course of four double filtration plasma exchanges, which resulted in marked clinical improvement. Painful muscle cramps disappeared and muscle stiffness reduced within a day after the first plasma exchange. The patient's improvement continued, but his condition declined again about ten months after plasma exchange. Immunoadsorption therapy was then performed, and this treatment was also effective.

Antibodies↗

PubMed1999

Effect of insulin on naturally occurring gingivitis rats with diabetes.

It is well known that diabetes mellitus aggravates both the severity and progression of periodontal disease. We sought to further explore biologic mechanisms of this relationship using naturally occurring gingivitis rats (ODUS/Odu) rendered diabetic by 65 mg/kg intravenous injection of streptozotocin (STZ). Insulin was administered daily to one group of the rats beginning 4 weeks after STZ injection (STZ-insulin group). Others received no insulin (STZ group). A third group that received no STZ was kept as controls. Eight weeks after STZ injection, sterilized liquid paraffin was injected peritoneally into all three groups, and peritoneal macrophages were collected 4 days later. Macrophage chemotaxis was measured by the membrane filter method using a 48-well microchemotaxis chamber with zymosan activated serum used as a chemotactic stimulant. Blood glucose levels, body weight, plaque indices, pocket depths, serum triglyceride and hemoglobin A1C levels were also determined. We found that blood glucose levels, body weight and triglycerides recovered to normal values in the STZ-insulin group. Further, control of blood glucose resulted in diminished plaque indices, and pocket depths returned to values seen in the controls. Chemotaxis and phagocytosis of peritoneal macrophages improved slightly in the STZ-insulin group, but did not return to levels seen in the pretreatment state. Although insulin resulted in some improvement in leukocyte function damaged by induced diabetes mellitus, recovery was incomplete.

Animals↗