Biomedical subjects

K Fukuda

Publications and source records attributed to K Fukuda.

At least 1,063 records · Page 59Linked to original sources

PubMedDate not supplied

Vascular access system for continuous arterial infusion of a protease inhibitor in acute necrotizing pancreatitis.

We used a vascular access system (VAS) for continuous arterial infusion (CAI) of a protease inhibitor in two patients with acute necrotizing pancreatitis. The infusion catheter was placed into the dorsal pancreatic artery in the first patient and into the gastroduodenal artery in the second, via a femoral artery approach. An implantable port was then connected to the catheter and was secured in a subcutaneous pocket prepared in the right lower abdomen. No complications related to the VAS were encountered. This system provided safe and uncontaminated vascular access for successful CAI for acute pancreatitis.

Adult↗

PubMedDate not supplied

A study on the relationship between adenoid vegetation and rhinosinusitis.

The relationship between adenoidal-nasopharyngeal ratios (AN ratios) and sinusitis were evaluated in 404 children. The AN ratios of children with snoring, mouth breathing, or nasal obstruction (major symptoms of adenoidal enlargement) were significantly higher than those of children without these symptoms. However, the AN ratios of children with sinusitis were almost equal to those of normal children.

Adenoids↗

PubMedDate not supplied

Establishment of human mucosal microvascular endothelial cells from inferior turbinate in culture.

Human microvascular endothelial cells were isolated and cultured from the mucosa of inferior turbinates. Using dish-coated collagen and a medium composed of a 1:1 mixture of sarcoma 180-conditioned medium and Dulbecco's modified Eagle's medium (containing 10% fetal bovine serum and 75 micrograms/mL endothelial cell growth factors prepared from bovine pituitary glands), these cells grew rapidly to confluence and survived serial passages until the 16th population doubling level. The cells were identified as endothelial cells by their morphology, immunostaining of factor VIII antigen, and cytochemical staining with Ulex europeus agglutinin. Furthermore, Weibel-Palade bodies and numerous pinocytotic vesicles were confirmed by electron microscopy. Proliferation experiments demonstrated the need for either endothelial cell growth factor or tumor-conditioned medium. An exogenous matrix was also required for these cells in tissue culture. A tubule-like morphology appeared in the original monolayer of human microvascular endothelial cells after 1 month in the same plate, indicating that these cells have the ability to form tubules in the presence of sarcoma 180-conditioned medium.

Cell Division↗

PubMedDate not supplied

Biological rhythms in patients with lissencephaly (agyria-pachygyria).

Lissencephaly is a congenital malformation of the brain characterized by an extensive absence of cerebral gyral formation. Polysomnograms were recorded in 8 cases with lissencephaly (4 of agyria and 4 of pachygyria), and 24-h secretion of growth hormone, prolactin, luteinizing hormone, follicle-stimulating hormone and cortisol was examined in 6 of the 8 cases. The sleep-waking cycle and body temperature (BT) rhythm were studied in all 8 cases. The results were as follows: (i) the sleep-waking circadian rhythm was well preserved in 6 of the 8 cases; (ii) %REM (rapid eye movement) sleep decreased in 4 cases, but the ultradian rhythm of REM sleep was well observed in all cases except one; (iii) the secretion of GH and PRL showed normal or borderline increases with sleep; (iv) although these cases had not reached puberty, LH and FSH increased with sleep in 3 of 5 cases; (v) the circadian rhythm of cortisol secretion was preserved in all cases except one; (vi) BT showed a circadian rhythm after infancy. These findings suggest that the circadian rhythms function normally in lissencephaly, that the secretion of GH and PRL during sleep occurs almost normally, and that the cerebral cortex does not play a significant role in the regulation of these biological rhythms in lissencephaly.

Birth Weight↗

PubMedDate not supplied

Serial EEG and sleep polygraphic studies on lissencephaly (agyria-pachygyria).

We carried out serial EEG studies on 12 cases of lissencephaly (6 of agyria and 6 of pachygyria), polysomnograms being recorded in 8 of the 12 cases. Fourteen Hz sleep spindles appeared from early infancy in all cases. They were poorly observed after the age of 1 year, and 5-11 Hz high-amplitude rhythmic activity (HARA) of more than 300 microV appeared predominantly in place of the 14 Hz spindles. Both the 14 Hz spindles and HARA showed asymmetry, but the dominant cerebral area for both types of waves was much the same. Four of the 6 agyria cases showed hypsarrhythmia within the first 6 months after birth, 3 of the 4 cases showing asymmetric hypsarrhythmia at first. Their hypsarrhythmia consisted of very high-voltage 5-7 Hz slow sharp waves and delta waves. The EEG abnormalities transformed from hypsarrhythmia to focal spikes in the 6 pachygyria cases. The polygraphic study on 8 cases revealed that the proportion of REM sleep decreased in 3 cases and the REMs/min values decreased in 7. Infantile spasms occurred in 4 of the 8 cases. The REM/min values decreased in all of these 4 cases, and, furthermore, the proportion of REM sleep decreased in 3 of the 4 cases. These findings suggest that lissencephaly involves a disorder of the brainstem, and that the combination of brainstem lesions and severe cerebral dysplasia is important for the manifestation of infantile spasms in lissencephaly.

Aging↗

PubMedDate not supplied

A case of noninflammatory corneal edema following anterior-posterior radial keratotomy (Sato's operation) successfully treated by topical corticosteroid.

BACKGROUND: Corticosteroids seem to affect the functions of corneal endothelial cells directly in addition to their anti-inflammatory effect. CASE: A 69-year-old man presented with blurred vision in his left eye and decreased visual acuity in both eyes. He had received anterior-posterior radial keratotomy for myopia in both eyes 40 years earlier. OBSERVATIONS: Both eyes showed mild corneal stromal edema in the pupil area. We diagnosed the condition as corneal edema secondary to cell loss and dysfunction of corneal endothelium after surgery. One month later, the stromal edema was further advanced in the left eye. Corneal thickness had increased from the initial value of 619 microm to 631 microm, and corrected visual acuity had decreased from 0.5 to 0.06. There were no signs suggesting inflammatory reaction. The left eye was then treated with topical corticosteroid eyedrops and subconjunctival corticosteroid injection. Two months later, corneal thickness had decreased to 546 microm and visual acuity had improved to 0.5. CONCLUSIONS: This case shows that topical corticosteroids may be effective in treating corneal edema by producing an anti-inflammatory effect and possibly activating the endothelium.

Administration, Topical↗

PubMedDate not supplied

An epidemiologic study of fatigue with relevance for the chronic fatigue syndrome.

We surveyed households in four rural Michigan communities to confirm a reported cluster of cases resembling chronic fatigue syndrome (CFS) and to study the epidemiology of fatigue in a rural area. Data were collected from 1698 households. We did not confirm the reported cluster. The prevalence of households containing at least one fatigued person was similar between communities thought to harbor the cluster and communities selected for comparison. Symptoms and features of generic forms of fatigue were very similar to those often attributed to CFS.

Adolescent↗

PubMedDate not supplied

Fatiguing illness among employees in three large state office buildings, California, 1993: was there an outbreak?

UNLABELLED: The objective was to determine if a cluster of chronic fatigue syndrome (CFS)-like illness had occurred among employees in two large state office buildings in northern California, and to identify risk factors for and features of fatiguing illness in this population. DESIGN: case-control study. POPULATION AND SETTING: Over 3300 current employees in two state office buildings and employees in a comparable "control" building. Information was collected on demographic and occupational variables, the occurrence of fatiguing illness for at least one month in the previous year, and the presence of 36 symptoms. A total of 3312 (82%) of 4035 employees returned questionnaires. Overall, 618 (18.7%) persons reported fatigue lasting at least one month; including 382 (11.5%) with fatigue of at least six months' duration and 75 (2.3%) with symptoms compatible with a CFS-like illness. Independent risk factors for fatigue lasting one month or longer were found to be Native American ethnicity (OR 2.4, CI 1.1,5.3), Hispanic ethnicity (OR 1.7, CI 1.3,2.3), female sex (OR 1.5, CI 1.2,1.9), gross household incomes of less than $50,000 (OR 1.3, CI 1.1,1.6), and less than a college education (OR 1.3, CI 1.1,1.6). Similar risks were observed for persons who reported fatigue lasting six months or longer. Female sex (OR 3.2, CI 1.7, 6.4) was the only independent risk factor found for those persons classified as having a CFS-like illness. Case prevalence rates for all three categories of fatigue, as determined by multivariate analysis, were not significantly different among buildings. Despite finding a substantial number of employees with fatiguing illness in the two state office buildings, the prevalence was not significantly different than that for a comparable control building. Previously unidentified risk factors for fatigue of at least one month and at least six months identified in this population included Hispanic ethnicity, not having completed college, and income below $50,000.

Adult↗

PubMedDate not supplied

Apoptosis-associated cleavage of beta-catenin in human colon cancer and rat hepatoma cells.

Proteases belonging to the caspase family play a crucial role in apoptotic processes. Identification of protein cleavage specific to apoptosis may therefore provide further information about the mechanisms of apoptosis. In this study, apoptosis and necrosis were induced in cells of the human colon cancer cell lines, WiDr and DLD-1, and the resulting protein cleavage patterns investigated for beta-catenin. beta-Catenin was detected as a 92 kDa protein in control viable cells, while 65-72 kDa beta-catenin cleavage fragments were characteristically observed in apoptotic cells. These fragments were not observed in necrotic cell death. Similar apoptosis-specific beta-catenin cleavage was also demonstrated in the rat hepatoma cell line McA-RH7777, suggesting that the beta-catenin cleavage is a common event in apoptosis in various cell types. The formation of 65-72 kDa beta-catenin cleavage fragments was completely prevented by a caspase-1 inhibitor Z-VAD-CH2F and a caspase-3 inhibitor Z-DEVD-CH2F, indicating that the cleavage is associated with caspase-dependent process. Since beta-catenin is implicated in cell adhesion and signal transduction, these findings may suggest various possible roles of beta-catenin degradation in the dramatic cytoskeletal and morphological changes, as well as signaling events that accompany apoptosis.

Actins↗

PubMedDate not supplied

Location of functional regions of acetylcholine receptor alpha-subunit by site-directed mutagenesis.

The availability of cloned cDNAs encoding the four subunits of the Torpedo acetylcholine receptor, which can be expressed to make functional receptors in Xenopus oocytes, has made possible a detailed investigation of the functions of the different structural components of the receptor. The functional analysis of receptors with alpha-subunits altered at specific sites by site-directed mutagenesis of the cDNA has allowed the location of specific regions of the alpha-subunit molecule involved in acetylcholine binding and forming a transmembrane ionic channel.

Animals↗

PubMedDate not supplied

Role of acetylcholine receptor subunits in gating of the channel.

The Torpedo and calf acetylcholine receptors and hybrids composed of subunits from the two species have been produced in Xenopus oocytes by the use of the cloned complementary DNAs. Single-channel current measurements indicate that these receptors form channels of similar conductance but with different gating behaviour.

Animals↗

PubMedDate not supplied

Cloning, sequencing and expression of complementary DNA encoding the muscarinic acetylcholine receptor.

Cloning and sequence analysis of DNA complementary to porcine cerebral messenger RNA encoding the muscarinic acetylcholine receptor predict the complete amino-acid sequence of this protein. Expression of the complementary DNA produced functional muscarinic receptor in Xenopus oocytes. The muscarinic receptor is homologous with the beta-adrenergic receptor and rhodopsin in both amino-acid sequence and suggested transmembrane topography.

Amino Acid Sequence↗

PubMedDate not supplied

Location of a delta-subunit region determining ion transport through the acetylcholine receptor channel.

The combination of complementary DNA expression and single-channel current analysis provides a powerful tool for studying the structure-function relationship of the nicotinic acetylcholine receptor (AChR) (refs 1-5). We have previously shown that AChR channels consisting of subunits from different species, expressed in the surface membrane of Xenopus oocytes, can be used to relate functional properties to individual subunits. Here we report that, in extracellular solution of low divalent cation concentration, the bovine AChR channel has a smaller conductance than the Torpedo AChR channel. Replacement of the delta-subunit of the Torpedo AChR by the bovine delta-subunit makes the channel conductance similar to that of the bovine AChR channel. To locate the region in the delta-subunit responsible for this difference, we have constructed chimaeric delta-subunit cDNAs with different combinations of the Torpedo and bovine counterparts. The conductances of AChR channels containing chimaeric delta-subunits suggest that a region comprising the putative transmembrane segment M2 and the adjacent bend portion between segments M2 and M3 is involved in determining the rate of ion transport through the open channel.

Animals↗

PubMedDate not supplied

Molecular distinction between muscarinic acetylcholine receptor subtypes.

The muscarinic acetylcholine receptor (mAChR) mediates various cellular responses, including inhibition of adenylate cyclase, breakdown of phosphoinositides and modulation of potassium channels, through the action of guanine nucleotide-binding regulatory proteins. Pharmacologically distinguishable forms of the mAChR occur in different tissues and have provisionally been classified into M1 (I), M2 cardiac (II) and M2 glandular (III) subtypes on the basis of their difference in apparent affinity for antagonists. In an attempt to elucidate the molecular basis of the functional heterogeneity of the mAChR, we have cloned and sequenced DNAs complementary to porcine cerebral and cardiac messenger RNAs encoding mAChRs and have thereby deduced the primary structures of the receptor proteins. We report here that the messenger RNA generated by transcription of the cardiac complementary DNA directs the formation of a functional mAChR in Xenopus oocytes and that this mAChR differs from the mAChR formed by expression of the cerebral cDNA both in acetylcholine (ACh)-induced response and in antagonist binding properties. Our results provide evidence indicating that the mAChR encoded by the cerebral cDNA (designated as mAChR I) and the mAChR encoded by the cardiac cDNA (mAChR II) are of the M1 (I) and the M2 cardiac (II) subtype, respectively.

Acetylcholine↗

PubMedDate not supplied

The bilateral effect of stellate ganglion block on the facial skin blood flow.

BACKGROUND AND OBJECTIVES: It is our hypothesis that stellate ganglion block increases regional blood flow on the blocked side, but does not change cardiac output, suggesting that the corresponding regional blood flow on the contralateral side may decrease, which would be disadvantageous for patients with bilateral sympathetically-maintained pain. The aim of this study is to examine the effect of stellate ganglion block on facial skin blood flow. METHODS: Skin blood flow on the right and left forehead was measured by a laser blood flowmeter before stellate ganglion block and 15 minutes after the block. The block was performed for 8 outpatients with acute or chronic pain in the head or neck using a 24-gauge needle, 5 mL of 1% mepivacaine, and a paratracheal approach at the C6 transverse process. Time control without the block was obtained with 9 healthy volunteers. RESULTS: All the patients developed the Horner's syndrome on the blocked side, but not on the contralateral side. The facial skin blood flow increased from 7.5 +/- 1.1 mL/min/100 g to 14.5 +/- 1.4 mL/min/100 g on the blocked side (P < .01) and from 8.8 +/- 1.2 mL/min/100 g to 12.8 +/- 1.7 mL/min/100 g on the contralateral side (P < .05). The healthy volunteers without the block showed no significant change (from 10.1 +/- 0.8 mL/min/100 g to 10.3 +/- 0.7 mL/min/100 g). CONCLUSIONS: Our study suggests that stellate ganglion block may increase the contralateral regional skin blood flow.

Adult↗

PubMedDate not supplied

Mucinous cystadenoma with malignant transformation arising in the renal pelvis.

Mucinous cystadenoma with malignant transformation occupying the lower half portion of the right renal pelvis in a 69-year-old Japanese man was recorded. The patient had recent dysuria but no clinical history of pyelonephritis or urolithiasis. Under the clinical diagnosis of unusual renal cyst, the right total nephrectomy was performed. Grossly, the cystic tumor, 5 cm across, formed a monolocular lumen filled with mucins and showed no direct communication with the renal pelvis inside. Microscopically, the epithelial lining was characterized by a single layer of benign mucin producing columnar cells that scattered foci of non-invasive papillary projections with cell stratification and nuclear atypia suggestive of malignancy. Although there was non-specific chronic pyelitis, no pyelitis cystica et glandularis was encountered. Of circa 60 glandular neoplasms arising in the renal pelvis reported previously, adenomas are only five including two mucinous cystadenomas, while the remainder are adenocarcinomas. The histological findings of mucinous cystadenoma in the present case may represent the process of a transition from adenoma to adenocarcinoma. The result suggests the possibility that adenoma-carcinoma sequence may exist among the glandular neoplasma arising in the renal pelvis. The histogenesis was unclarified.

Aged↗

PubMedDate not supplied

Substratum-bound elastin peptide inhibits aortic smooth muscle cell migration in vitro.

Migration of smooth muscle cells (SMCs) of the media through the internal elastic lamina to the intima in response to various chemoattractants is considered to be an important event in the development of atherosclerosis. We evaluated the influence of elastin peptides prepared from normal aorta on migration of cultured rat aortic SMCs in vitro. Studies with filters coated with elastin peptides in a modified Boyden's chamber showed that the migratory response of cultured rat aortic SMCs in response to platelet-derived factors was impeded by filter-bound elastin peptides. The inhibitory effect appeared to be relatively specific for elastin peptides and for SMCs, as other matrix components (Types I, III, IV, and V collagens and fibronectin) did not impede SMC migration, and polymorphonuclear leukocytes were not impeded by elastin peptides. Elastin peptides in solution in the lower well caused the migratory response, and this response was also inhibited by filter-bound elastin peptides. Attractants such as platelet-derived factors and elastin peptides are likely to be present in the matrix around migrating SMCs. These studies suggest that elastin peptides adhering to the substratum or elastin, a major component of elastic fiber, may be one of the natural inhibitors of vascular SMC migration in response to chemoattractants in the fluid phase.

Animals↗

PubMedDate not supplied

Analysis of glycoproteins from nasal polyps and papillomas by affinity chromatography.

Glycoproteins were isolated from the particulate fraction of four nasal polyps and three nasal papillomas by affinity chromatography on lectins conjugated with agarose (Concanavalin A [Con A], wheat germ agglutinin [WGA], Ricinus communis agglutinin [RCA], peanut agglutinin [PNA], and Dolichos biflorus agglutinin [DBA]). The glycoprotein mixtures so isolated were then analyzed by sodium dodecyl sulfate gel electrophoresis. Glycoprotein profiles of nasal polyps were similar to each other, but were distinctively different from those of nasal papillomas. Binding sites for Con A, WGA, and RCA isolated from nasal papillomas contained intense bands with a molecular weight less than 15,000 daltons, which were absent in nasal polyps. The major component of PNA-binding sites of nasal polyps is of a molecular weight of 65,000 daltons, which was not detected in nasal papillomas.

Adult↗