Biomedical subjects

J Yasuda

Publications and source records attributed to J Yasuda.

At least 55 records · Page 3Linked to original sources

PubMed1999

[A case of preoperatively diagnosed primary pulmonary leiomyosarcoma].

A 29-year-old woman had been suffering from right back pain for 3 months. Chronic pulmonary thromboembolism was suspected and she was referred to our hospital. She presented with no risk factors for thromboembolism, and during the previous 6 months had lost 4 kg in body weight. Chest radiography showed nodular shadows in the lower field of the right lung. Contrast-enhanced computed tomography demonstrated a filling defect in the right pulmonary artery and nodular lesions in the lower field of the right lung, which were considered to be signs of pulmonary infarction. Absence of perfusion into the right lung was demonstrated by a perfusion scan. Right heart catheterization showed normal pressure in the pulmonary arteries, and pulmonary angiography showed an abrupt cutoff of the right pulmonary artery, which was similar to the finding of pulmonary thromboembolism. A transvenous catheter suction biopsy was performed in the right pulmonary artery and the histopathologic findings yielded a diagnosis of leiomyosarcoma. The patient underwent surgical resection under total cardiopulmonary bypass. A large tumor completely filled the right main pulmonary artery and invaded the posterior wall of the pulmonary trunk close to the left main pulmonary artery. Primary pulmonary leiomyosarcoma is a rare tumor and its prognosis is very poor. Radical surgical resection is the only effective treatment, but early diagnosis is very difficult. Transvenous catheter suction biopsy is a useful procedure for the early diagnosis of pulmonary artery sarcoma.

Adult↗

PubMed1998

Detection of DNA abnormalities by arbitrarily primed PCR fingerprinting: allelic losses in chromosome 10q in lung cancers.

DNA fingerprinting using arbitrarily primed PCR (AP-PCR) is useful for detecting cancer-specific DNA aberrations without targeting any particular genes or knowing any nucleotide sequences in advance. AP-PCR fingerprinting is an efficient method for finding loss of anonymous chromosomal regions in cancers. We analyzed DNA from 44 human non-small cell lung cancers by fingerprinting using a single primer and found a loss of signal intensity in a DNA fragment amplified from chromosome 10 (fragment F) in 15 tumors. The detailed location of the fragment F locus on chromosome 10q was determined by PCR-based analysis of radiation hybrid panels using a sequence-tagged site established for the fragment. In 12 of the 15 tumors, loss of the signal detected by AP-PCR fingerprinting was in agreement with the results obtained by analysis of allelic imbalances using 7 polymorphic CA-microsatellite DNA markers for loci around the fragment F locus (p=0.0009). We conclude that a hitherto unknown suppressor gene for lung cancer resides at 10q in the vicinity of fragment F.

Alleles↗

PubMed1998

A mammalian scaffold complex that selectively mediates MAP kinase activation.

The c-Jun NH2-terminal kinase (JNK) group of mitogen-activated protein (MAP) kinases is activated by the exposure of cells to multiple forms of stress. A putative scaffold protein was identified that interacts with multiple components of the JNK signaling pathway, including the mixed-lineage group of MAP kinase kinase kinases (MLK), the MAP kinase kinase MKK7, and the MAP kinase JNK. This scaffold protein selectively enhanced JNK activation by the MLK signaling pathway. These data establish that a mammalian scaffold protein can mediate activation of a MAP kinase signaling pathway.

Animals↗

PubMed1998

Molecular karyotype (amplotype) of metastatic colorectal cancer by unbiased arbitrarily primed PCR DNA fingerprinting.

Genomic instability characterizes the aneuploid cancer cell. Losses of genetic material are critical in cancer by exposing recessive mutations in tumor suppressor genes. Gains of genetic material also may lead to overexpression of genes contributing to tumor progression either in the presence or absence of mutation. However, the detection of moderate gains (such as tri-tetraploidy) has been a challenge in cancer research. Unbiased DNA fingerprinting by the arbitrarily primed PCR allows the detection of moderate gains (in addition to losses) of DNA sequences of known chromosomal localization. We have generated in this manner a molecular karyotype of metastatic colon cancer. This amplotype shows that sequences from several chromosomes undergo both losses (1, 4, 9, 14, and 18) and gains (6, 7, 12, and 20) in over half of the tumors. Moreover, gains of sequences from chromosomes 8 and 13 occurred in most tumors, indicating the existence in these chromosomes of positive regulators of cell growth or survival that are under strong positive selection during tumor progression. We conclude that overrepresentation of these chromosomal regions is a critical step for metastatic colorectal cancer. Comparative amplotype analysis from primary and metastatic tumors suggest the existence in chromosome 4 of gene(s) whose loss is specifically selected in cells that reach the metastatic stage.

Alleles↗

PubMed1998

Ultrasonographic and serologic studies of experimental cysticercosis in rats infected with Taenia taeniaeformis.

Rats experimentally infected with Taenia taeniaeformis were followed-up until 14 weeks post inoculation with eggs (PIE) by hepatic ultrasonographic (US) image and serum antibody response analyses. Parasitic cysts could be imaged as small (2 mm in diameter) anechoic areas with or without a parenthesis-like echogenic small line from two weeks PIE. Immunoblot analysis using antigens from oncospheres (TtO), 30-day-old (TtM-30) and 300-day-old metacestodes (TtM-300) revealed that: (1) these three different developmental stages showed their own unique patterns suggesting the presence of stage-specific antigens; (2) faint IgM antibody responses to some components of TtO and TtM-30 or TtM-300 could be detected from one and two weeks PIE, respectively, and (3) IgG responses to some major components of both TtO and TtM-300, and TtM-30 were easily detected from four and five weeks PIE onwards, respectively. Both TtO and TtM (especially TtM-300) appeared to be highly useful for detection of antibody responses in experimentally infected rats. Due to the easiness in preparation of antigens, fully developed metacestodes may be the best candidate antigens for serodiagnosis. These results strongly suggest that both US image and antibody analyses using antigens from fully developed metacestodes are useful for detection of the early stage of cysticercosis in laboratory animal model.

Animals↗

PubMed1998

Comparison of attenuation and liver-kidney contrast of liver ultrasonographs with histology and biochemistry in dogs with experimentally induced steroid hepatopathy.

Digital analysis of liver ultrasound images (USGs) was compared to histological and serum enzyme activity results in dogs with steroid-induced hepatopathy. Steroid hepatopathy was used as a model for diffuse liver diseases. Prednisolone administration resulted in increased acoustic backscatter (hyperechogenicity) of the liver with reference to the kidney and significant depth attenuation (hyper-attenuation). Absolute changes were determined by histogram analysis of echo means (Ems) of area samples (1 x 1 cm) of liver and kidney at the depth of 2 cm (liver-kidney contrast) and at 2 cms and 4 cm (depth attenuation). Liver-kidney contrast histograms correlated well with histology but were more sensitive than serum enzyme activity and subjective visual interpretation. Depth attenuation was the earliest detectable acoustic change. These results suggested that depth attenuation is an early and sensitive indicator of steroid hepatopathy. Liver-kidney contrast correlates well with histology and may complement biopsy examination during follow-up studies.

Alanine Transaminase↗

PubMed1998

Endoscopic and transcutaneous ultrasonographic findings and grey-scale histogram analysis in dogs with caerulein-induced pancreatitis.

Endoscopic ultrasonography (EUS), grey-scale histogram analysis of EUS images, and transcutaneous ultrasonography (TUS) were done in four dogs with caerulein-induced pancreatitis. One other dog was subjected to laparotomy and biopsy specimens were collected for histopathology. By EUS, the pancreatic lesions were first detected at 60 minutes after the start of caerulein infusion. They were detected after 120 to 150 minutes when using TUS. EUS findings included swelling, a more distinct lobular pattern, subcapsular hypoechoic areas, and anechoic stripes through the pancreatic tissue. No marked changes in the histogram analysis was seen until 30 minutes. From 30 to 60 minutes, a decrease in the mean brightness of the pancreatic tissue was observed. These changes in mean brightness reflected histopathological findings showing vacuolization of acinar cells and interstitial oedema of the pancreas. These findings indicated that EUS can detect slight and diffuse changes in pancreatic tissue. Furthermore, grey-scale histogram analysis detects histopathological changes more sensitively than endoscopic ultrasound images.

Animals↗

PubMed1998

A proline-rich motif (PPPY) in the Gag polyprotein of Mason-Pfizer monkey virus plays a maturation-independent role in virion release.

Virus assembly represents one of the last steps in the retrovirus life cycle. During this process, Gag polyproteins assemble at specific sites within the cell to form viral capsids and induce membrane extrusion (viral budding) either as assembly progresses (type C virus) or following formation of a complete capsid (type B and type D viruses). Finally, the membrane must undergo a fusion event to pinch off the particle in order to release a complete enveloped virion. Structural elements within the MA region of the Gag polyprotein define the route taken to the plasma membrane and direct the process of virus budding. Results presented here suggest that a distinct region of Gag is necessary for virus release. The pp24 and pp16 proteins of the type D retrovirus Mason-Pfizer monkey virus (M-PMV) are phosphoproteins that are encoded in the gag gene of the virus. The pp16 protein is a C-terminally located cleavage product of pp24 and contains a proline-rich motif (PPPY) that is conserved among the Gag proteins of a wide variety of retroviruses. By performing a functional analysis of this coding region with deletion mutants, we have shown that the pp16 protein is dispensable for capsid assembly but essential for virion release. Moreover, additional experiments indicated that the virus release function of pp16 was abolished by the deletion of only the PPPY motif and could be restored when this motif alone was reinserted into a Gag polyprotein lacking the entire pp16 domain. Single-amino-acid substitutions for any of the residues within this motif confer a similar virion release-defective phenotype. It is unlikely that the function of the proline-rich motif is simply to inhibit premature activation of protease, since the PPPY deletion blocked virion release in the context of a protease-defective provirus. These results demonstrate that in type D retroviruses a PPPY motif plays a key role in a late stage of virus budding that is independent of and occurs prior to virion maturation.

Animals↗

PubMed1998

Arterial and mixed venous oxygen desaturation during incremental exercise in patients with chronic pulmonary disease.

We evaluated arterial and mixed venous oxygen desaturation during symptom-limited exercise in patients with chronic pulmonary disease. Patients were divided into five groups according to disease: [chronic pulmonary emphysema (CPE), chronic bronchitis (CB), pulmonary tuberculosis sequalae (TB-seq), fibrosing lung disease (FLD), and pulmonary vascular disease (PVD)]. There were no significant difference in the values of arterial (PaO2) and mixed venous (PvO2) oxygen tension before and at the end of exercise among the five groups, whereas absolute decreases in PvO2 were significantly larger in PVD and FLD. The changes in PvO2 were similar to the changes in the coefficient of oxygen delivery (COD) which is equal to oxygen transport divided by oxygen consumption. These results suggest that the relative decrease in oxygen transport during exercise due to the high ratio of oxygen extraction by tissues is an important factor to determine decreases in PvO2 in pulmonary hypertensive disease and fibrosing lung disease.

Aged↗

PubMed1998

The canine alkaline phosphatases: a review of the isoenzymes in serum, analytical methods and their diagnostic application.

This paper reviews the alkaline phosphatases in canine serum, the analytical methods used for qualitative and/or quantitative detection of these isoenzymes, and the diagnostic significancy of each of these isoenzymes. The paper further describes some of the latest advances in our knowledge of the canine alkaline phosphatases and possible areas of future research.

Alkaline Phosphatase↗

PubMed1997

Separation and quantification of corticosteroid-induced, bone and liver alkaline phosphatase isoenzymes in canine serum.

Quantifying alkaline phosphatase (ALP) isoenzymes in canine serum would provide a useful index in a clinical laboratory. To achieve this goal, we tested a semi-automatic assay combining wheat germ lectin (WGL) precipitation and chemical inhibition of isoenzymes of the TNS gene with levamisole to quantify bone ALP (BALP) and corticosteroid-induced ALP (CALP), respectively. The liver ALP (LALP) isoenzyme was then calculated from the equation: TALP = BALP + LALP + CALP BALP, LALP and CALP standards from serum of puppies, bile-duct ligated dogs and dogs on 4.4 mg/kg/day prednisolone for 30 days, respectively, were used. The suitability of standard sera was tested by affinity electrophoresis. Levamisole (4.2 mM) inhibits 98% of BALP and LALP but only 42% CALP. Multiplying measured CALP by 1.8 gives the total CALP value in serum. WGL precipitated 92.3% BALP, 23.3% LALP and 26.8% heated CALP standards. These values were used to adjust precipitated ALP to obtain the exact levels of BALP. WGL was then tested on pooled serum standards in which the relative proportions of all the ALPs were known and controlled. BALP was adequately quantified except when LALP and CALP levels were extremely high. The assay was also applicable under conditions resulting in high ALP. Therefore, combining WGL and levamisole inhibition provides an adequate separation and quantification of canine ALP isoenzymes. The method has great potential for diagnostic use and should be tested further for routine implementation.

Adjuvants, Immunologic↗

PubMed1997

[Evaluation of the assay technique for detection of anti-chlamydial IgA and IgG antibodies in PID patients].

The purpose of this study is to evaluate the usefulness and limitation of Rapizyme CHLAMYDIA, enzyme-linked immunosorbent assay (ELISA) for qualitative detection of anti-chlamydial IgG and IgA antibodies, in the serum of 92 PID patients and 73 pregnant women, compared with those of Sero IPALISA CHLAMYDIA. The result of Rapizyme analysis was obtained within 10 minutes with no special devices. Overall agreements of Rapizyme and Sero IPALISA were 90.9% (IgG) and 90.3% (IgA) in the total patients, 88.0% (IgG) and 85.9% (IgA) in PID patients, and 94.5% (IgG) and 95.9% (IgA) in pregnant women. The positive rate of Chlamydia in PID was 17.4% (16/92). Positive agreement of Rapizyme in Chlamydia positive PID and pregnant women was 100% in both IgG and IgA, and negative agreement was also 100%. Positive agreement in Chlamydia negative PID was 100% in both IgG and IgA, and negative agreement was 90.0% (IgG) and 83.3% (IgA). The results of Rapizyme were in close agreement with those of Sero IPALISA. COI (cut off index) of Sero IPALISA clearly decreased in 3 of 6 PID patients during a 3 to 6 months period after chemotherapy, but those changes were not observed in Rapizyme. These results suggest that Rapizyme CHLAMYDIA is a useful diagnostic kit for Chlamydial PID of outpatients.

Antibodies, Bacterial↗

PubMed1997

The age dependent levels of serum ALP isoenzymes and the diagnostic significance of corticosteroid-induced ALP during long-term glucocorticoid treatment.

Three isoenzymes of total alkaline phosphatase (TALP) are known in canine serum: Bone alkaline phosphatase (BALP), liver alkaline phosphatase (LALP) and corticosteroid-induced alkaline phosphatase (CALP). Using an assay developed by combining selective precipitation of BALP by wheat germ lectin (WGA) and an automated levamisole inhibition method for quantifying CALP, age-related reference ranges of the isoenzymes in 75 canine serum samples were investigated. BALP comprised 96, 38 and 26% of TALP in young, middle aged and old dogs, respectively, and CALP was respectively 12, 11 and 27% of TALP. LALP was less than 10% in the young but represented more than 50% of TALP in middle aged and old dogs. Furthermore, the significance of monitoring LALP and CALP and their relationship to hepatopathy in dogs receiving long term prednisolone therapy was assessed. In this study, TALP increased in all dogs receiving prednisolone. But only LALP was responsible in dogs with minor vacuolization of the liver, while in severely degenerated cases both LALP and CALP increased. It is concluded that a high TALP due solely to LALP, rather than LALP and CALP represents lesser liver pathologic involvement. Monitoring the 2 isoenzymes has greater significancy in assessing in the level of liver damage than relying on an increased TALP value alone. Quantifying the individual isoenzymes may further be useful in assessing the clinical significance of these isoenzymes in various conditions that result in elevated TALP values.

Adrenal Cortex Hormones↗

PubMed1997

Reference data on the anatomy, hematology and biochemistry of 9-month-old silver foxes.

Anthropometric, anatomical, hematological and biochemical reference values were estimated in clinically healthy male and female 9-month-old silver foxes. The coefficients of variation of anthropometric and anatomical measurements for 9-month-old silver foxes were as low as previously reported for adult foxes. However, in relation to body size, all measurements were smaller. Compared with adult silver foxes, higher values were observed in serum levels of triglyceride, phospholipid, beta-lipoprotein, blood urea nitrogen and total protein. Similarly, higher levels were obtained for serum enzymes, especially aspartate aminotransferase (AST), lactate dehydrogenase (LDH) and creatine kinase (CK). The high levels of these serum enzymes may be due to handling stress. Inorganic phosphorus and calcium concentrations in the young foxes were also high. The alkaline phosphatase (ALP) level, reflecting the level of bone growth, was higher than that of adults. Biochemical values of beta-lipoprotein glucose and calcium in male 9-month-old silver foxes were lower than those of females, whereas those of total cholesterol, total protein, fructosamine, iron, albumin and beta-globulin were higher.

Animals↗

PubMed1997

A new T-lymphocyte cloning assay for detection of in vivo mutations in the human hypoxanthine-guanine phosphoribosyltransferase gene.

The X-linked hypoxanthine-guanine phosphoribosyl transferase (hprt) gene is a target of analyses of in vivo mutation frequencies in circulating T-lymphocytes. We established a novel, accessory cell-free cloning method of T-lymphocytes with a hprt mutation by a combined use of recombinant interleukin-2, conditioned medium from activating T-lymphocytes and culture plates coated with anti-CD3 monoclonal antibody. Using the method, we examined mutation frequencies of the hprt gene in T-lymphocytes from six healthy individuals, nine patients with colon cancer including two patients from different families with hereditary nonpolyposis colon cancer and six cancer-free relatives of the patients. In six healthy individuals, the mean cloning efficiency and mutation frequency (MF) of the hprt gene in T-lymphocytes were 0.51 +/- 0.28 and 9.4 +/- 7.5 x 10(-6), respectively. These data were similar to the reported values. The mean MFs in the nine colon cancer patients (10.6 +/- 7.3 x 10(-6)) were not significantly different from those of the 12 cancer-free individuals (11.6 +/- 9.4 x 10(6)). The correlation between mutation frequencies and age of the individuals was significant regardless of the presence or absence of cancers. The single-strand conformation polymorphism analyses of nested RT-PCR products of hprt mRNA were done in 33 mutant clones from five members of a family of which MF values were high. All the analyzed mutant clones show a genetic aberration in the coding region of the hprt gene. At least 28 of 33 mutants were independent. Our method provides a new versatile tool for in vivo analysis for mutations of the hprt gene.

Adult↗

PubMed1997

Short-term hemodialysis treatment in dogs and cats with total uretic obstruction.

This study evaluated the single-pass system for the short-term dialysis treatment of dogs and cats with experimental renal failure. The hemodialyzer was equipped with a thin and highly permeable Cuprophan membrane. Four animals (two dogs and two cats) with total uretic obstruction were dialyzed twice in a one-week period. The vascular access by venipuncture of external jugular vein delivered more than 5 ml/min/kg/body weight of blood repeatedly, even for the cats. The evaluation of the effects of the blood flow, dialysate flow and ultrafiltration pressure revealed that the blood flow was the most important factor for effective dialysis. A 300 ml/min dialysate flow provided enough clearance of blood urea nitrogen and creatinine. The ultrafiltration pressure played an important role in ensuring that the fluid removal was constant. Laboratory studies revealed a 50.0% (range 42.0 to 59.3%) reduction of blood urea nitrogen, a 48.7% (range 42.5 to 58.7%) reduction of creatinine, and a 49.8% (range 34.3 to 66.2%) reduction of inorganic phosphate during the dialysis treatment. No dialysis disequilibrium syndrome was shown by the clinical signs. We conclude that this short-term dialysis using a single-pass system for small animals was sufficiently applicable to dogs and cats, and that the optimal duration of the dialysis was 2 hours.

Animals↗

PubMed1996

Isolation of DNA sequences amplified at chromosome 19q13.1-q13.2 including the AKT2 locus in human pancreatic cancer.

In the human pancreatic cancer cell line PANC1, we detected several DNA fragments with abnormally intensified signals by restriction landmark genomic scanning. Major five of these fragments were cloned. All of the cloned fragments were mapped at the 19q13.1-13.2 region where the AKT2 oncogene was located. Southern blotting using the cloned DNA fragments and a fragment of AKT2 cDNA as probes revealed that the AKT2 gene was amplified in 3 of 12 pancreatic cancer cell lines analyzed including PANC1 and in 3 of 20 primary pancreatic cancers. The AKT2 gene was overexpressed in the 3 cell lines with the amplified gene. The results suggest that the AKT2 gene is a candidate oncogene activated by amplification in some human pancreatic cancers.

Base Sequence↗

PubMed1996

Chromosomal assignment of human DNA fingerprint sequences by simultaneous hybridization to arbitrarily primed PCR products from human/rodent monochromosome cell hybrids.

We have developed a technique for the simultaneous chromosomal assignment of multiple human DNA sequences from DNA fingerprints obtained by the arbitrarily primed polymerase chain reaction (AP-PCR). Radioactively labeled human AP-PCR products are hybridized to DNA fingerprints generated with the same arbitrary primer from human/rodent monochromosome cell hybrids after electroblotting to a nylon membrane. Human-specific hybridization bands in the human/rodent fingerprints unambiguously determine their chromosome of origin. We named this method simultaneous hybridization of arbitrarily primed PCR DNA fingerprinting products (SHARP). Using this approach, we determined the chromosomal origins of most major bands of human AP-PCR fingerprints obtained with two arbitrary primers. Altogether, the chromosomal localization of near 50 DNA fragments, comprehensive of all human chromosomes except chromosomes 21 and Y, was achieved in this simple manner. Chromosome assignment of fingerprint bands is essential for molecular karyotyping of cancer by AP-PCR DNA fingerprinting. The SHARP method provides a convenient and powerful tool for this purpose.

Animals↗