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Biomedical subjects

K Shimada

Publications and source records attributed to K Shimada.

At least 559 records · Page 31Linked to original sources
PubMed1997

Effect of oestradiol replacement in ovariectomized chickens on pituitary LH concentrations and concentrations of mRNAs encoding LH beta and alpha subunits.

Plasma concentrations of oestradiol and LH and steady-state pituitary concentrations of the mRNAs encoding the LH beta and alpha subunits in the gland were measured at intervals of 1 month for 5 months in female chickens. In addition, feedback regulation by oestradiol of concentrations of mRNAs encoding these LH subunits was studied in ovariectomized young (3-week-old) and adult hens. Concentrations of the mRNAs encoding the LH beta and alpha subunits increased significantly before sexual maturity and the changes were highly correlated with increases in plasma and pituitary concentrations of LH. Ovariectomy significantly reduced circulating plasma concentrations of oestradiol but increased pituitary concentrations of mRNAs encoding LH beta and alpha subunits and pituitary and plasma concentrations of LH in adult laying hens. In addition, in 3-week-old chickens, ovariectomy induced an increase in plasma and pituitary gland concentrations of LH. This ovariectomy-induced mRNA expression and tissue and plasma increases of LH were prevented by oestradiol replacement. These data suggest that a negative feedback mechanism by ovarian oestradiol inhibits LH release from the pituitary and pituitary LH biosynthesis in chickens.

Animals↗
PubMed1997

Unilateral pulmonary edema in a patient with ischemic heart failure.

A 72-year-old woman with a history of anterolateral myocardial infarction was in severe respiratory distress with frothy sputum production. Electrocardiogram and echocardiogram detected evidence of ischemic change due to anterolateral myocardial injury. Chest roentogenogram showed unilateral, right side pulmonary edema with a clear left lung field. Mechanical ventilation and diuretic administration contributed to her recovery from heart failure and pulmonary edema. Computed tomographic scan showed no abnormality of the bilateral lung fields or pulmonary vasculature; however, pulmonary perfusion scan and pulmonary angiography revealed reduced blood perfusion in the entire left lung field. Although we have no histological evidence, some pulmonary parenchymal change on the left side might have been the cause of unilateral pulmonary edema in this case. In conclusion, a woman with ischemic heart failure developed unilateral pulmonary edema on the right side, showing reduced blood perfusion on the left side.

Aged↗
PubMed1997

Osteosynthesis for the treatment of non-union of the lateral humeral condyle in children.

We reviewed the results of osteosynthesis for the treatment of an established non-union of the lateral humeral condyle in sixteen children whose average age was nine years (range, four to thirteen years) at the time of the operation. The average interval between the injury and the operation was five years (range, five months to ten years). The presenting symptoms were pain in the elbow in seven patients, apprehension in nine, a cubitus valgus deformity in six, limitation of motion in three, and dysfunction of the ulnar nerve in four. The average duration of follow-up was eleven years (range, four to thirty-two years). Osseous union was achieved after the initial operation in thirteen patients. Of the three patients who had a persistent non-union, two had a second operation and the third, who was asymptomatic, refused additional operative intervention. The result was rated excellent in eight patients, good in seven, and poor in one, with use of a modification of the functional rating index of Broberg and Morrey. The patient who had a poor result had evidence of avascular necrosis of the fragment.

Adolescent↗
PubMed1997

CD8+ T lymphocyte counts as an adjunctive predictor of cytomegalovirus retinitis in patients with acquired immunodeficiency syndrome.

We encountered a case of cytomegalovirus (CMV) retinitis with spontaneous regression in association with an increased number of CD8+ but not CD4+ T lymphocytes in a patient with acquired immunodeficiency syndrome (AIDS). Thus, we examined the number of CD4 and CD8 counts at the diagnosis of CMV retinitis and compared with those of Pneumocystis carinii pneumonia (PCP). All 21 patients with a confirmed diagnosis of PCP (22 episodes) and 14 CMV retinitis patients were included in this study. Although PCP occurred after depletion of CD4 count to below 200/microl, CD8 count at that time varied widely and remained normal in some patients (median: 276.5/microl, range: 133-900/microl). In contrast, as CMV retinitis occurred after further depletion of CD4 count to below 50/microl, CD8 count decreased to below 500/microl (median: 238/microl, range: 43-448/microl) (p<0.05; PCP vs CMV retinitis). The values of the sensitivity and specificity for CMV retinitis obtained at the cutoff point of either 400/microl in CD8 count and 50/microl in CD4 count were similar. When these two cutoff points were combined, the positive predictive value was 46%. Monitoring of CD8 count may prove valuable as an additional predictor of CMV retinitis in patients with AIDS after CD4 depletion.

AIDS-Related Opportunistic Infections↗
PubMed1997

Morphometric comparison of the motor trigeminal neurons.

Comparative morphological and morphometric studies of the motor trigeminal nucleus (MTN) were carried out on the brains of an alligator, a human being and a rat for the first time. Differences in neurons regarding sizes, areas, numbers, column volumes, neuropil indices and circulatory ratios were found. The results showed that the positions and shapes of the MTN were different, and the shapes of motor neurons were different, too. The average area of motor trigeminal neurons was the largest in the alligator, compared with the area in the human being, and the rat; the number of neurons and the column volume of MTN were the largest in the human being. As for the neuropil indices, the value was in descending order: alligator, human being and rat; whereas for the circulatory ratio of neuronal cell bodies, the order was rat, alligator, and human being. We conclude that the size of motor neurons in the MTN may be related to the power of masticatory muscles, and there may be a connection between jaw sizes and shapes and sizes of the motor neurons in the MTN.

Alligators and Crocodiles↗
PubMed1997

Immunohistochemical study of extracellular matrices and elastic fibers in a human sternoclavicular joint.

In this study, we clarified the distribution of elastic and oxytalan fibers in a human sternoclavicular joint (SCJ) using a color image system and in extracellular matrices using immunoperoxidase staining. Fine elastic fibers (EFs) were scattered in the fibrous layer of the sternoclavicular disk. This articular disk was composed of a collagenous bundle on the sternum side of the articular disk in the SCJ and cellular components including connective tissue on the clavicular side of the articular disk. The thickness of the disk gradually increased from the inferior to superior portion. Collagen fibers type I, III and V and other extracellular matrices (ECMs) were detected in the hypertrophic zone in the clavicular and sternum side of the SCJ and in the connective tissue of the articulatio condylar. On the cervical surface of the articular disk, cellular activity was higher than on the sternum surface.

Adult↗
PubMed1997

Substantial volar defects of the fingers treated with free thenar flaps.

Two patients presented with severe injuries to the left index finger (amputation and partial amputation of the distal phalanx, together with partial degloving). These injuries were successfully treated with free thenar flaps over 40 mm long. In both cases, the superficial palmar branch of the radial artery originated in its usual position and branched normally and could be anastomosed to the digital artery. Both patients have recovered well.

Adult↗
PubMed1997

[Multidisciplinary approach to an elderly patient with severe congestive heart failure].

A 77-year-old woman with severe valvular heart disease and chronic renal failure was admitted to hospital for control of her heart condition and to improve her ability to perform activities of daily living. In the past 2 years, she had been admitted to hospital four times due to severe congestive heart failure, and she was bedridden because of muscle weakness. A multidisciplinary approach was taken. A cardiologist reassessed her medications and determined an exercise level in co-operation with a physical therapist. After 40 days of rehabilitation, the patient was able to walk 200 m without the help of a cane. With an increase in the exercise level, her cardiothoracic ratio increased from 68 to 74%. The furosemid was then increased from 40 to 60 mg per day and 20 mg of denopamine was added, which resulted in a decrease of the cardiothoracic ratio to 66%. Dietary assessment revealed her usual salt intake was more than 10 g per day, and the dietitian advised the patient that her daily salt intake should be lower than 7 g and water intake less than 800 ml per day. Consultations with social-service personnel made revealed problems in her family and living environment, and she was advised of available social services. For good compliance, the patient had her medication explained by a pharmacist. Assessment of activities of her daily living and intensive education about congestive heart failure were performed by the nurse in charge. After discharge, a nurse team visited her home every two weeks and watched for signs of heart failure. This comprehensive intervention prevented an exacerbation of heart failure and readmission for nine months.

Aged↗
PubMed1997

[Continent urinary reservoir using dilated renal pelvis of non-functioning pelvic kidney in a girl with cloacal exstrophy].

We performed construction of continent urinary reservoir in an 8-year-old girl with cloacal exstrophy who had double stoma of ileostomy and colon conduit. Preoperative evaluation revealed non-functioning right kidney with severely dilated renal pelvis and calyxes in her pelvis. Urinary reservoir was constructed using detubularized colon segment which had been used as the urinary conduit and dilated renal pelvis of non-functioning pelvic kidney. Using Mitrofanoff's principle, continent catheterizable channel was also made of the anterior wall of the renal pelvis. Postoperative course was uneventful. Reservoir capacity increased to 350 ml one and half year postoperatively and she is almost dry with clean intermittent catheterization 5 times a day. Dilated upper urinary tract is one of the ideal material for bladder enlargement that avoids the complication associated with the use of gastrointestinal tract.

Child↗
PubMed1997

[Pathological study of the kidney and the lung in patients with Potter sequence].

PURPOSES: The condition in infants showing the characteristic facial abnormalities, limb deformities, and pulmonary hypoplasia induced by oligohydramnios is termed Potter sequence (PS). In addition to bilateral renal agenesis, Potter sequence could be caused by other urological abnormalities such as cystic dysplasia and obstructive uropathy. Although lethal in most of the patients with PS, some exceptional infants were reported to survive in spite of the antenatal demonstration of oligohydramnios from renal abnormalities. These surviving patients put new questions to us regarding the management of both respiratory and renal failure starting from the newborn periods. The diversity of clinical courses in patients with antenatally detected PS may imply that this entity has a spectrum of severity. Our study of infants autopsied on the diagnosis of PS was undertaken to determine various histological grade of the kidneys and the lungs. MATERIALS AND METHODS: Thirty-two autopsy cases of PS (19 males and 13 females) diagnosed by the presence of the characteristic stigmata, oligohydramnios, and renal or urological abnormalities were studied retrospectively. Patients were divided according to the urological abnormalities into 3 groups; renal hypodysplasia, urinary obstruction, and polycystic kidney disease (PCKD). Renal histology was evaluated by two parameters; renal glomerular count (RGC), and dysplastic grade. Developmental aspects of the lung were judged by lung/body-weight ratio (L/ B ratio) and radial alveolar count (RAC) proposed by Emery. RESULTS: The underlying urological disorders included renal hypodysplasia in 22 patients, obstruction in 7, and polycystic kidney disease in 3. Dysplastic grade of 29 patients with hypodysplasia and obstruction consisted of grade 4 in 12 patient, grade 3 in 9, and grade 2 in 8. In 10 kidneys from 8 patients with grade 2-dysplasia, RGC was significantly fewer than that of normal fetuses for the gestational age. The term patient with PS showed the glomerular count equivalent to normal fetus of around 25 weeks of gestation. L/B ratio indicated definite pulmonary hypoplasia in 25 of 29 patients. The ratio was much smaller than normal in another 4 patients. RAC was calculated in 24 patients; of these only 2 had normal count for gestational age. In another 22, the number of air space stopped to increase at about 20 to 25 weeks of gestation. There was a tendency for L/B ratio to decrease according to dysplastic grade (1.3% for grade 2 vs. 0.9% for grade 3 and 4). CONCLUSION: The primary urological abnormalities leading to PS included bilateral renal hypodysplasia, obstructive uropathy, and PCKD. Histological study of the kidneys indicates that PS is the spectrum disease with various degree of nephron formation. The development of the lung depends, in part, on the grade of renal dysplasia.

Abnormalities, Multiple↗
PubMed1997

Altered circadian rhythm of blood pressure and cerebrovascular damage.

An abnormal circadian rhythm of blood pressure [i.e. a lesser or 'reverse' nocturnal fall of blood pressure (nondippers)] is associated with cerebrovascular damage including intracranial hemorrhaging, thrombosis, and vascular dementia. Silent cerebrovascular damage such as lacunae and periventricular hyperintensity lesions is not infrequently detected in apparently healthy hypertensive elderly subjects by brain magnetic resonance imaging and also is more common among nondippers than it is among dippers. Although no exact cause-effect relationship is known, a decrease in nocturnal fall of blood pressure might be secondary to a site-specific injury to the brain resulting in an impairment of central autonomic nervous system functioning. Besides nondipping, evidence suggests that the extreme dipping (a marked nocturnal fall of blood pressure) should be considered a type of abnormal diurnal blood pressure variation in elderly patients with hypertension who are likely to have advanced silent cerebrovascular damage. The pathogenic significance of 'extreme dipping' might be an 'artificial' excess reduction in blood pressure at night beyond the lower limit of blood pressure in the autoregulation of cerebral blood flow that is probably induced by antihypertensive agents. It is also possible that a greater blood pressure variability in extreme dippers itself accelerates the hypertensive target-organ damage. Prospective follow-up of subjects with these distinct subtypes of abnormal circadian blood pressure variation as well as trials comparing a group of treated patients with various degrees of dipping with a group of untreated counterparts may establish the validity of assessing these distinct circadian rhythms of blood pressure as a useful clinical parameter in the management of hypertension.

Journal Article↗
PubMed1997

[Structural polymorphism of ACTBP2 STR region].

We investigated structural polymorphisms of the ACTBP2-STR region by sequence analysis instead of using PCR-amplified fragment length polymorphisms. A gel spot extraction reamplification method using 2% agarose gel was effective for preparing the individual alleles from zygotes with a length difference of more than 16bp. In a survey of polymorphisms in 116 unrelated Japanese subjects, alleles from 73 zygotes were prepared by this method. The STR structure of the allele was determined from the forward sequence image. The allele designation was made according to the number of the repeated AAAG tetranucleotide and also the position of the inserted AA or AG dinucleotide. Forty-three zygotes impossible to separate were first sequenced in a forward direction. Among them, 28 zygotes were typed directly by analysing the sequence image which exhibited a peculiar overlap of two sequences. For the remaining 15 zygotes, it was possible to type by analysing the forward and reverse sequence images together. This investigation revealed the presence of 79 kinds of alleles in 116 zygotes of ACTBP2. The most frequent allele was type 19, which accounted for 9.5% although this was still a small portion. Genotypes 19/20, 19/21, 18/21, 18/10AA12, 19/13AA11 and 20/13AA15 were detected from two subjects, respectively, and others including the type 19 homozygyote were unique.

Alleles↗
PubMed1997

Analysis of amyloid deposition in a transgenic mouse model of homozygous familial amyloidotic polyneuropathy.

Amyloid fibrils derived from the Japanese, Portuguese, and Swedish types of familial amyloidotic polyneuropathy all consist of a variant transthyretin (TTR) with a substitution of methionine for valine at position 30 (TTR Met 30). In an attempt to establish an animal model of TTR Met-30-associated homozygous familial amyloidotic polyneuropathy and to study the structural and functional properties of human TTR Met 30, we generated a mouse line carrying a null mutation at the endogenous ttr locus (ttr-/-) and the human mutant ttr gene (6.0-hMet 30) as a transgene. In these mice, human TTR Met-30-derived amyloid deposits were first observed in the esophagus and stomach when the mice were 11 months of age. With advancing age, amyloid deposits extended to various other tissues. Because no significant difference was detected in the onset, progression, and tissue distribution of amyloid deposition between the ttr-/- and ttr+/+ transgenic mice expressing 6.0-hMet 30, endogenous normal mouse TTR probably does not affect the deposition of human TTR Met-30-derived amyloid in mice. TTR is a tetramer composed of four identical subunits that binds thyroxine (T4) and plasma retinol-binding protein. The introduction of 6.0-hMet 30 into the ttr-/- mice significantly increased their depressed serum levels of T4 and retinol-binding protein, suggesting that human TTR Met 30 binds T4 and retinol-binding protein in vivo. The T4-binding ability of human TTR Met 30 was confirmed by the analysis of T4-binding proteins in the sera of ttr-/- transgenic mice expressing 6.0-hMet 30. The T4-binding studies also demonstrated the presence of hybrid tetramers between mouse and human TTR subunits in the ttr+/+ transgenic mice expressing 6.0-hMet 30.

Amyloid↗
PubMed1997

[Beneficial effects of continuous hemodiafiltration after cardiac surgery in patients with chronic renal failure].

From December 1993 to June 1996, fourteen patients with chronic renal failure (CRF) were underwent cardiac surgery. Thirteen of them had coronary artery bypass grafting (CABG) and one patient had aortic valve replacement. We employed continuous hemodiafiltration (CHDF) with or without peritoneal dialysis in eleven cases in the early postoperative course of open heart surgery. In these cases, the usefulness of CHDF were examined. CHDF was started after 16.9 +/- 13.7 hours of surgery, and continued for 31.9 +/- 18.0 hours. We adjusted blood flow as 80 ml/min, perfusate flow of hemofilter as 500 ml/hr, and the activated clotting time (ACT) as 150-200 seconds with heparin or nafamostat mesilate. No hemorrhagic tendency was observed. Mean serum creatinine level before and after 24 hours of CHDF was 5.6 +/- 2.2 and 5.6 +/- 2.1 mg/dl respectively, and it was not elevated. The average removal volume was 2,223 +/- 1,256 ml for the first 24 hours, and pulmonary wedge pressure was decreased from 9.0 +/- 2.3 to 6.4 +/- 3.0 mmHg (p < 0.05). However, there was no significant change at cardiac output before and after CHDF. Total dose of dopamine and dobutamine were unchanged. No significant change were noted at systemic vascular resistance and pulmonary vascular resistance. We conclude that CHDF allows an adequate removal of fluid and waste products without deleterious effects on hemodynamics even in patients after cardiac surgery. CHDF is a safe and effective alternative in patients with CRF after cardiac surgery.

Aged↗
PubMed1997

Factor VII and fibrinogen levels examined by age, sex, and other atherosclerotic risk factors in a Japanese population. The Jichi Medical School Cohort Study.

Factor VII coagulant activity (FVIIc) and fibrinogen (Fbg) levels have been investigated as cardiovascular risk factors. We studied these two factors with stratification for age, sex and blood pressure, and the relation with other atherosclerotic risk factors in a Japanese general population. The subjects were 3,139 Japanese (1,315 males and 1,824 females) aged 30 to 89 in 1992 and 1993. A linear increase with age was observed in the levels of Fbg in both men and women, but no differences were observed between men and women in each age group. A linear increase with age was also seen in the levels of FVIIc in women, but the levels of FVIIc in men were significantly higher for the age group 40-49 years than for any other age group. The levels of FVIIc in women were significantly higher than in men at age > or = 60 years. As concerning the effect of alcohol intake status, Fbg had a tendency to decrease with alcohol intake. Fbg and FVIIc levels were associated with an increase in smoking status in men, but no association was seen in women in either Fbg or FVIIc. FVIIc was positively correlated with age, body mass index, total cholesterol, triglycerides and fasting insulin level. Fbg was positively correlated with age, systolic blood pressure, diastolic blood pressure, total cholesterol, LDL-cholesterol and triglycerides in women, but Fbg had few positive correlations with risk factors in men. A comparison with previous Western studies showed that the Fbg levels of our Japanese population were lower than those of the Caucasians studied, but the present FVIIc levels were nearly the same level or slightly higher than theirs. The association of Fbg and FVIIc and with other cardiovascular risk factors in Japanese was similar to those observed in Caucasians.

Adult↗
PubMed1997

[The usefulness of fibrin glue spraying combined with CDDP for lung cancer].

The local slow release of an anticancer agent by one route is a form of treatment. There have been numerous reports to date that this approach might be a promising adjuvant for systemic therapy. We investigated the spraying of the operative field at a local site with cisplatin, which is considered the most effective carcinostatic in the field of lung cancer, and reported it in clinical cases selected in applying a Pilot-Study. The feature of this method is to use fibrin to spray drugs uniformly over a wide field. We expect it will be an adjuvant for postoperative purification and other uses.

Adenocarcinoma↗
PubMed1997

[Evaluation of coronary artery bypass grafts with magnetic resonance imaging].

Currently, the efficacy of magnetic resonance imaging (MRI) for evaluating coronary artery disease has been reported. In this study, we have evaluated the usefulness and the problems of MRI for evaluating the patency of coronary artery bypass grafts. Thirty-five patients who received coronary artery bypass grafting (CABG) were evaluated by using MRI for determining the graft patency compared with conventional coronary angiography. There were 30 men and 5 women. The mean age was 61.2 years (range 45 to 75). The 35 patients had a total of 92 grafts (28 internal thoracic artery, 7 gastroeploic artery and 57 saphenous vein grafts). Magnetic resonance coronary angiogram (MRCA) was performed with SIGNA HORIZON 1.5 T (GE Inc.) by using 2D-FASTCARD sequence. All patients underwent imaging in the transverse and coronal planes, most had imaging in the sagittal plane, and a few had in the oblique plane. By using MRCA, 82 of 90 grafts were diagnosed correctly as patent, and 1 of 2 grafts were diagnosed correctly as occluded. Thirty-four of 40 LAD grafts (85%), 20 of 22 RCA grafts (91%) and 29 of 30 Cx grafts (97%) were correctly evaluated. The efficacy of MRCA for evaluating the patency of coronary artery bypass grafts was recognized. But the sternal wire (stainless steel) and hemoclip interfere with the interpretation and reduce the sensitivity. Higher sensitivity may be obtained by changing the material of the sternal wires and hemoclips at coronary surgery.

Aged↗