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Y Furuya

Publications and source records attributed to Y Furuya.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Tsutsugamushi disease (scrub typhus) in Japan: epidemiological aspects].

Epidemiological aspects of tsutsugamushi disease (scrub typhus) in Japan in 1998 were analyzed using questionnaires. Four hundred and sixteen scrub typhus cases were reported in 24 prefectures in 1998. The annual number of the patients in 1998 was similar to those in the preceding three years. There was no sex difference. The patients at the age of 51 or greater accounted for 72% of the total cases. Patients engaged in farming and forestry accounted for 32% and 14% cases, respectively. Fifty-six, 21 and 19% were reported in Kyusyu, Kanto and Tohoku-Hokuriku districts, respectively, 96% of the total cases being reported in these 3 districts. Most cases were reported from April through June with some from October through December in Tohoku-Hokuriku districts, while most cases were reported from October through December in other districts, including Kyusyu and Kanto districts. Thus, there was a difference in epidemic seasons among the districts. Serotypes of scrub typhus rickettsia were analyzed by serum antibody titers in the Kyusyu district. The novel Kawasaki and Kuroki types were major strains; however, no geographical difference was seen within the Kyusyu district. Interestingly, 24 cases were diagnosed only by the new serotypes not by the classical serotypes (Kato, Karp and Gilliam) in serological tests. This result suggests that further investigations are required to determine the prevalent serotypes in each district and to improve the serological tests. This was the first comprehensive report of epidemiology of scrub typus in entire Japan. Information obtained in the present study provides deep insight into prediction, diagnosis, treatment and prevention of scrub typhus in Japan.

Adolescent↗
PubMed2001

[Tsutsugamushi disease (scrub typhus) in Japan: clinical features].

Clinical features of tsutsugamushi disease (scrub typhus) were analyzed, based on 416 cases reported in Japan in 1998. Three major clinical symptoms: eschar, fever and rash were found in 87%, 98% and 92% of the cases, respectively. Elevated levels of CRP, GOT, GPT and LDH were observed in 96%, 85%, 78% and 91%, respectively. These clinical and laboratory findings were observed in the majority of the cases and considered important for diagnosis. Disseminated intravascular coagulation developed in 21 cases, indicating that scrub typhus can be life threatening. Lymphadenopathy was observed in 51% of the cases. Enlarged lymph nodes were limited to the local sites in 75% of these lymphadenopathy cases and most of these sites were adjacent to eschars. Most eschars were scabbed and located in the abdomen and the lower half of the body, especially the feet. This suggests that these parts are frequently exposed to tsutsugamushi mites. Furthermore, the skin is soft in these parts and covered by cloth. These factors may make it possible for mites to keep biting without being noticed for several hours, long enough for rickettsial transmission. Interestingly, eschar and rash were absent in 14% and 8% of the cases, respectively. This result suggests that the cases without the unique symptoms may have been misdiagnosed as common cold or other febrile illnesses. One hundred and fifty-four suspected cases were not scrub typhus cases by the serological tests. The three major clinical symptoms were present in approximately a half of these negative cases, eschar being observed in approximately 70%. This may suggest the presence of new type of scrub typhus can not be diagnosed by the present laboratory tests. Clinical features of scrub typhus in Japan were well revealed, and information obtained in the present study is useful for improving clinical diagnosis. It should, however, be stressed that there were cases that could not be correctly diagnosed only by the clinical symptoms, suggesting that it is important to improve the serological tests.

Diagnosis, Differential↗
PubMed2001

Accumulation of medium chain acyl-CoAs during beta-oxidation of long chain fatty acid by isolated peroxisomes from rat liver.

We have reported fatty alcohol synthesis accompanied by chain elongation in liver peroxisomes (Biochim. Biophys. Acta, 1346, 38 (1997)). In the present experiment, we studied what kind of acyl-CoA(s) destined to be utilized as primer for fatty alcohol synthesis accumulate(s) during peroxisomal beta-oxidation. Peroxisomes were prepared from rat liver treated with clofibrate, a peroxisome proliferator, and incubated with [U-14C]palmitate, in order to investigate acyl-CoAs after beta-oxidation. At 1 mM concentration, MgATP activated beta-oxidation, but inhibited beta-oxidation at concentrations higher than 1 mM. After incubation of peroxisomes with palmitate, various acyl-CoAs were formed. Among medium-chain labelled acyl-CoAs, octanoyl-CoA was mainly detected. These results suggest that octanoyl-CoA accumulates during beta-oxidation of palmitate. When peroxisomes were incubated with [9,10-(3)H]palmitate and [9,10-(3)H]stearate, among medium-chain acyl-CoAs, octanoyl-CoA and decanoyl-CoA were primarily detected, respectively, suggesting the occurrence of at least 4 cycles of beta-oxidation of both fatty acids by peroxisomes.

Acyl Coenzyme A↗
PubMed2001

Synthesis of southern (C1'-C11') and eastern (C8-C18) fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger.

Synthesis of the southern C1'-C11' and eastern C8-C18 fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger, was achieved. The southern fragment was synthesized by using the Evans aldol reaction and cis-selective iodoetherification as the key steps in a 9.6% overall yield (7 steps). The eastern fragment was constructed via the Julia coupling reaction and cis-selective iodoetherification in a 3.0% overall yield (8 steps from the known epoxide).

Furans↗
PubMed2001

Changes in quantitative profile of extracellular matrix components in the kidneys of rats with adriamycin-induced nephropathy.

Extracellular matrix components (ECMs) in histological sections of the kidney cortex from the rats with adriamycin (ADR)-induced nephropathy (5 mg/kg, i.v.) were quantified by an immunohistochemical micromethod. Changes in kidney histopathology and urine and blood biochemistry were investigated. Enlarged kidneys were granular on the surface and pale in color in ADR-treated rats, and these rats had kidneys with glomeruli with expanded mesangial area and with capillary aneurysm. Severe albuminuria, hypoalbuminemia, hypercholesterolemia and disorders in other nephrotic parameters were observed in ADR-treated rats. Type I and IV collagens, fibronectin and laminin contents in the renal cortex of ADR-treated rats at 10 weeks were 329, 317, 263 and 295%, respectively, higher than in each vehicle control, and those at 28 weeks were 1,211, 930, 1,057 and 1,012%, respectively. The glomerular sclerotic abnormalities progressed in a time-dependent manner. Moreover, there was a strong correlation between the ECM levels and serum creatinine and blood urea nitrogen levels. In conclusion, microquantification provided useful information for accurate diagnosis and prognosis of nephrotic lesions and is a good tool to assess the advancement of renal disorders in patients with nephropathy.

Albuminuria↗
PubMed2000

Global and regional techniques for monitoring cerebral oxidative metabolism after severe traumatic brain injury.

The disturbance of normal mechanisms of oxygen delivery and metabolism is a hallmark of severe traumatic brain injury (TBI). In the past, investigations into the status of cerebral oxygen metabolism depended on changes in the differences in oxygen content between arterial and jugular venous blood. The development of jugular venous oximetry permitted continuous monitoring of jugular venous oxygen saturation, thereby overcoming earlier limitations caused by intermittent sampling. Neuromonitoring techniques that utilize only jugular vein sampling provide information only about global cerebral metabolism, but direct measurement of brain tissue oxygen tension via intraparenchymal probes makes possible the assessment of regional cerebral oxygen metabolism. Regional and global neuromonitoring techniques are not competitive or mutually exclusive. Rather, they are best regarded as complementary, with each providing valuable information that has a direct bearing on patient outcomes. The authors review the currently available techniques used in the monitoring of cerebral oxidative metabolism in patients who have sustained severe TBI.

Brain↗
PubMed2000

MCF-7 growth inhibition by ultraviolet radiation and 5-fluorouracil: the importance of treatment sequence.

Effective treatment of certain cancers with 5-fluorouracil (5-FU) and irradiation is well established; however, the most effective combination of these agents remains controversial. Although 5-FU has been identified as a radiosensitizer, the mechanism of action remains unknown. To assess the effect of combination, 5-FU and ultraviolet (UV), we constructed a new in vitro model with MCF-7 human breast cancer cells that measures growth inhibition and morphologic changes in nuclear argyrophilic nucleolar organizer regions (AgNORs). Cells were incubated in media containing 0, 50, 100 and 500 ng/ml 5-FU for 48 h, they were also exposed to UV irradiation of 90 J/m(2) at the beginning, middle, or end of the incubation period. The cells were incubated for an additional 48 h with 5-FU free media. A combined treatment with 5-FU and UV radiation demonstrated an additive inhibitory effect. The strongest growth inhibition was observed when UV exposure was at the beginning of the 5-FU treatment at 5-FU concentrations of 100 and 500 ng/ml. To elucidate the activity of 5-FU radiosensitization, we investigated the aggregation Pof AgNOR, which we previously established to reflect rRNA inhibition. A combined treatment with 5-FU and UV radiation accelerated the rate of AgNOR aggregation at 5-FU concentrations of 50 and 100 ng/ml. The timing of UV irradiation did not affect the rate of AgNOR aggregation. A combined treatment with 5-FU and UV radiation showed an additive inhibitory effect on MCF-7 cell growth that might be explained, in part, by rRNA inhibition.

Antimetabolites, Antineoplastic↗
PubMed2000

Morphological study of the regeneration mechanism of acetic acid-injured colon crypts in the rat.

The regeneration mechanism of injured rat colonic mucosa with 1% acetic acid was certified in this study. The injured colons were studied periodically on experimental days 1, 3, 5, 7, 15, and 20 with light and scanning electron microscopy. Specimens were examined in paraffin sections stained with hematoxylin and eosin; crypts were isolated with the HCl digestion method; and three-dimensional stromal collagen tissue was prepared with the NaOH cell maceration method. Damage to the mucosal and submucosal layers peaked between the 1st and 3rd days with edema, regeneration, necrosis, and inflammation. The edema and inflammation subsided, and mucosal atrophy and crypt reduction remained at around 1 week. At 2 weeks the mucosa became thick, and crypts showed many branches in their lower two-thirds; and by 3 weeks the mucosa had recovered to almost normal. The ratio of number of crypts at the base and surface was almost 1.5 on the 15th day and 1.0 on the 20th day, suggesting that each branch progresses upward to create an independent crypt. We believe that the fission mechanism plays an important role in crypt repair after acetic acid injury of the colonic mucosa. As the proliferative zone of the colonic crypt is localized at the crypt base, fission of the crypt starting at the base and progressing up to the surface is the most reasonable and efficient mechanism for repair by increasing the number of crypts.

Acetic Acid↗
PubMed2000

Isolation, characterization, and molecular cloning of a thermostable xylitol oxidase from Streptomyces sp. IKD472.

A thermophilic bacterium, Streptomyces sp. IKD472, that can oxidize xylitol was isolated from a hot spring and was found to produce xylitol oxidase. The purified enzyme was a monomeric protein with an apparent molecular weight of 43 k as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration. This novel enzyme is capable of catalyzing the oxidation of one mole of xylitol to form one mole each of xylose and hydrogen peroxide. Since the V(max)K(m) value for xylitol was two and four times higher than those for galactitol and n-sorbitol, respectively, the enzyme was designated as xylitol oxidase. The enzyme was stable in the pH range from 5.5 to 10.5 and at temperatures up to 65 degrees C. The optimal temperature and pH were 55 degrees C and pH 7.5, respectively. Xylitol oxidase bound one mole of FAD as a coenzyme per mole of protein. The amino acid sequence of the NH2 terminus and the fragments obtained by lysylendpeptidase digestion of xylitol oxidase were determined for preparation of synthetic oligonucleotides as hybridization probes. A 2.8-kb chromosomal fragment hybridizing to the probes was cloned into pUC18 in Escherichia coli. The gene consists of an open reading frame of 1245 by that encodes a protein containing 415 amino acids with a molecular weight of 44,730 but without the conserved nucleotide-binding sequence, Gly-X-Gly-X-X-Gly. The amino acid sequence has 70% identity to putative oxidoreductase from Streptomyces coelicolar, 51% to sorbitol oxidase from Streptomyces sp., and 26% to L-gulonolactone oxidase from rat in terms of the overall amino acid sequence. DNA manipulation of the cloned gene in E. coli, by alteration of a strong promoter and a synthesized ribosome-binding sequence at an appropriate position, resulted in overproduction of xylitol oxidase 100 times more than that produced in the original Streptomyces sp. IKD472. The enzyme properties of recombinant xylitol oxidase were the same as those of the authentic enzyme. Stable xylitol oxidases, which allow easier quantitative analysis of xylitol, are useful for clinical applications.

Journal Article↗
PubMed2000

Daily intermittent decreases in serum levels of parathyroid hormone have an anabolic-like action on the bones of uremic rats with low-turnover bone and osteomalacia.

The calcium receptor agonist (calcimimetic) compound NPS R-568 causes rapid decreases in circulating levels of parathyroid hormone (PTH) in rats and humans. We hypothesized that daily intermittent decreases in serum PTH levels may have different effects on bone than do chronically sustained decreases. To test this hypothesis, we compared two NPS R-568 dosing regimens in rats with chronic renal insufficiency induced by two intravenous injections of adriamycin. Fourteen weeks after the second adriamycin injection, creatinine clearance was reduced by 52%, PTH levels were elevated approximately 2.5-fold, and serum 25(OH)D3 and 1,25(OH)2D3 levels were reduced substantially. Treatment by daily per os gavage, which decreased PTH levels intermittently, or continuous subcutaneous infusion, which resulted in a sustained suppression of serum PTH levels, then began for 8 weeks. Despite the hyperparathyroidism, the adriamycin-injected rats developed a low-turnover bone lesion with osteomalacia (fourfold increase in osteoid volume in the proximal tibial metaphysis) and osteopenia (67% decrease in cancellous bone volume and an 18% reduction in bone mineral density at the distal femur). Daily administered (but not infused) NPS R-568 significantly increased cancellous bone volume solely by normalizing trabecular thickness, and increased femoral bone mineral density by 14%. These results indicate that daily intermittent, but not sustained, decreases in PTH levels have an "anabolic-like" effect on bones with a low-turnover lesion in this animal model of chronic renal insufficiency.

Aniline Compounds↗
PubMed2000

Spectral characteristics of hypernasality in maxillectomy patients.

To reveal the acoustic characteristics associated with hypernasality and to ascertain their correlation to the severity of hypernasality, 30 speech samples produced by 15 maxillectomy patients were acoustically analysed with and without an obturator prosthesis in place. The isolated, sustained Japanese vowel /i/ was used as the stimulus for acoustic measurement and perceptual judgment to evaluate the severity of hypernasality. Normalized 1/3-octave spectral analysis demonstrated the spectral characteristics of hypernasality as a rise in amplitude between the first and second formants around the 1 kHz region, and a reduction in amplitude of the frequencies higher than the second formant. High correlation was shown between the perceptual ratings and the predicted values derived from stepwise regression analysis.

Adult↗
PubMed2000

Sectional prosthesis with hollow obturator portion made of thin silicone layer over resin frame.

Magnetically retained sectional obturator prostheses, consisting of a hollow obturator portion made of thin silicone layer over a resin frame and a denture portion, were fabricated to alleviate some of the limitations of silicone materials, and applied to two edentulous patients with maxillectomy defects. The silicone obturator allowed profound engagement of undercuts within the defect, resulting in adequate retention, support and stability of the prostheses for over 3 years. The patients have achieved improvement in speech and mastication without complications, by use of the obturator prostheses.

Acrylic Resins↗
PubMed2000

Effect of prostatic biopsy on free-to-total prostate-specific antigen ratio in patients with prostate cancer.

BACKGROUND: We determined the effect of prostatic biopsy on the changes in total and free prostate-specific antigen (PSA) and free-to-total PSA ratio (F/T ratio) and examined if there are differences in these parameters between patients with benign and malignant histologic findings. METHODS: The concentration of total and free PSA and the F/T ratio were determined in 35 men before and 1 h after prostatic biopsy. The level of PSA was measured with a chemiluminescent enzyme assay. Of 35 patients, nine were diagnosed as having prostate cancer. RESULTS: In patients whose biopsy revealed cancer, the F/T ratio was lower than those without cancer, although there were no differences in total and free PSA value before prostatic biopsy. One hour after prostatic biopsy, there was an increase in the level of total and free PSA and the F/T ratio in all men. The increase in the F/T ratio was greater in patients whose biopsies revealed no prostate cancer. In patients with stage B cancer, these parameters increased more than those with stage C/D cancer. CONCLUSION: Prostatic biopsy causes a dramatic increase in total and free PSA. The F/T ratio also increased after biopsy. The PSA response to prostatic biopsy might be different in patients with and without prostatic malignancy. The response might also be different according to stage of prostate cancer.

Aged↗
PubMed2000

Changes in serum prostate-specific antigen following prostatectomy in patients with benign prostate hyperplasia.

PURPOSE: To investigate how prostatectomy for patients with benign prostate hyperplasia (BPH) affected the serum prostate-specific antigen (PSA) levels. METHODS: In 193 patients who underwent prostatectomy for BPH, serum PSA levels were measured before and three months after the operation. The total prostate weight measured by transrectal ultrasonography (TRUS) and the weight of the surgical specimen were examined in relation to the pretreatment PSA value and the changes in PSA levels after the operation. RESULTS: The transition zone volume measured by TRUS could well estimate the weight of the surgical specimen in patients who underwent subcapsular prostatectomy and transurethral resection of the prostate. The concentration of preoperative serum PSA showed a significant correlation with the prostatic volume and with the transition zone volume. Removal of 1 g of BPH tissue reduced serum PSA levels by an average of 0.18 ng/mL. The change in serum PSA levels after the prostatectomy correlated with the total prostatic gland volume and with the transition zone volume. CONCLUSIONS: The elevated PSA levels in patients with BPH were caused by the enlargement of the transition zone. After the resection of the adenoma, PSA levels should be expected to decrease to the normal range.

Adenoma↗
PubMed2000

Calcimimetic NPS R-568 prevents parathyroid hyperplasia in rats with severe secondary hyperparathyroidism.

UNLABELLED: Calcimimetic NPS R-568 prevents parathyroid hyperplasia in rats with severe secondary hyperparathyroidism. BACKGROUND: Secondary hyperparathyroidism (secondary HPT) in chronic renal insufficiency (CRI) is characterized by multiglandular hyperplasia. METHODS: In this study, we investigated the effects of the calcimimetic NPS R-568 on the parathyroid gland in rats with CRI induced by ligation of the renal arteries and severe secondary HPT induced by dietary phosphorus loading. Six days after surgery, high-phosphorus diet feeding was started, and NPS R-568 was administered to the rats for 56 days either by daily gavage (30 or 100 micromol/kg) or by continuous subcutaneous infusion (20 micromol/kg. day). RESULTS: After 54 days, serum PTH levels in vehicle-treated CRI rats were 1019 vs. 104 pg/mL in sham-operated controls. Infusion of NPS R-568 maintained serum PTH at levels comparable with those of sham-operated controls, whereas daily gavage also prevented much of the increase in CRI controls and decreased PTH levels intermittently in a dose-dependent fashion. Parathyroid gland enlargement was caused predominantly by hyperplasia. Total cell number per kg body wt was 3.5-fold higher in vehicle-treated CRI rats than in sham-operated controls. Both infusion and high-dose gavage of NPS R-568 completely prevented the increase in parathyroid cell number. CONCLUSION: These results demonstrate that the calcimimetic compound NPS R-568 can prevent both the increase in serum PTH levels and parathyroid hyperplasia in rats with CRI and severe secondary HPT. Moreover, these changes occurred despite decreases in serum 1, 25(OH)2D3 and increases in serum phosphate, suggesting a dominant role for the calcium receptor in regulating parathyroid cell proliferation.

Aniline Compounds↗