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Biomedical subjects

H Hayashi

Publications and source records attributed to H Hayashi.

At least 325 records · Page 18Linked to original sources
PubMed1999

Sporadic amyotrophic lateral sclerosis of long duration mimicking spinal progressive muscular atrophy: a clinicopathological study.

We report an autopsy case of amyotrophic lateral sclerosis (ALS) clinically diagnosed as spinal progressive muscular atrophy (SPMA). The patient was a Japanese woman without hereditary burden. She developed muscle weakness of the distal part of the left lower extremity at age 42, followed by muscle weakness and atrophy of the right lower extremity and upper extremities. At age 57, she needed transient ventilatory support. Slight weakness in the facial muscles and fasciculation of the tongue appeared at age 60. At age 61, she died of sudden respiratory arrest. During the clinical course, neurological examination revealed neither Babinski signs nor hyperreflexia. The neuropathological examination revealed not only neuronal loss with gliosis in the facial nucleus, hypoglossal nucleus, and anterior horns of the spinal cord, but also loss of Betz cells and degeneration of the pyramidal tracts. Based on these clinicopathological findings and review of literature, we conclude that sporadic ALS mimicking SPMA is present.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Clinical significance of serum p53 antibody detection on chemosensitivity assay in human colorectal cancer.

BACKGROUND AND OBJECTIVES: Alteration of the p53 gene product occurs frequently during progression of colorectal cancer. Recently, mutated p53 protein was found to induce the production of anti-p53 antibodies in the serum of patients. The purpose of this study was to evaluate the relationship between p53 status in serum and chemosensitivity in resectable colorectal cancer patients. METHODS: A total of 22 patients with primary colorectal cancer who underwent surgical treatment were examined for chemosensitivity with iable tumor samples using the Histoculture Drug Response Assay (HDRA). Serum samples of these patients for p53 antibodies were obtained before tumor resection and assayed in duplicate using an enzyme-linked immunosorbent assay kit. RESULTS: The inhibition index of 5-fluorouracil and cis-diamminedichloroplatinum (CDDP), determined by the HDRA method, in the seropositive group was significantly lower than that in the seronegative group (P < 0.01). Furthermore, significant statistical differences in chemosensitivity to 5-fluorouracil and CDDP were revealed depending on the presence of serum p53 antibodies. CONCLUSIONS: Detection of serum p53 antibodies, which reflects p53 mutations in tumor tissue, is a simpler method which correlates with chemosensitivity and may contribute to the selection of favorable chemotherapeutic strategies for colorectal cancer.

Adenocarcinoma↗
PubMed1999

Peritoneal lavage cytology findings as prognostic factor for gastric cancer.

The validity of lavage cytology for accurate gastric cancer staging is demonstrated in this study. Between 1988 and 1996, 29 cases (8. 4%) were revealed as positive among 347 patients with resectable gastric cancer in whom peritoneal lavage cytology was performed. The survival rate of cytology-positive patients in each stage was found to be worse than that of all other patients in the same stage. The prognostic factors selected by the univariate analysis were enrolled for multivariate analysis using Cox's proportional hazards model with the backward stepwise procedure. As a result, although cytology finding was selected as an independent prognostic factor, macroscopic finding of dissemination was not selected. Our data indicate that positive cytology findings indicated a poor prognosis, and therefore the results of peritoneal lavage cytology should be included as a factor in gastric cancer staging.

Analysis of Variance↗
PubMed1999

Importance of positive peritoneal lavage cytology findings in the stage grouping of gastric cancer.

Although peritoneal lavage cytology is widely performed during surgery for gastric cancer and the results have been reported to be one of the accurate prognostic factors, the cancer stage is determined independent of the results of lavage cytology according to the First English Edition of Japanese Classification of Gastric Carcinoma. In this study we demonstrated the validity of lavage cytology for accurately staging gastric cancer. Between 1988 and 1996, peritoneal lavage cytology was performed in 347 patients with resectable gastric cancer. Among them, cytology was positive in 29 cases (8.4%). The survival rate of the cytology-positive patients in each stage was worse than that of all patients in the same stage. The prognosis of patients with positive cytology findings and serosa-exposed gastric cancer was significantly worse than that of negative cytology findings and serosa-exposed gastric cancer, and similar to that of negative cytology findings and serosa-infiltrating gastric cancer. Our data indicated that positive cytology findings thus indicated a poor prognosis, and the prognostic difference between positive and negative cytology findings was approximately a one-stage difference in the Japanese stage grouping. Based on our findings, the results of peritoneal lavage cytology should thus be included in the factors for staging gastric cancer.

Ascitic Fluid↗
PubMed1999

Nucleotide sequences of two contiguous and highly homologous xylanase genes xynA and xynB and characterization of XynA from Clostridium thermocellum.

A 5.7-kbp region of the Clostridium thermocellum F1 DNA was sequenced and found to contain two contiguous and highly homologous xylanase genes, xynA and xynB. The xynA gene encoding the xylanase XynA consists of 2049 bp and encodes a protein of 683 amino acids with a molecular mass of 74,511 Da, and the xynB gene encoding the xylanase XynB consists of 1371 bp and encodes a protein of 457 amino acids with a molecular mass of 49,883 Da. XynA is a modular enzyme composed of a typical N-terminal signal peptide and four domains in the following order: a family-II xylanase domain, a family-VI cellulose-binding domain, a dockerin domain, and a NodB domain. XynB exhibited extremely high overall sequence homology with XynA (identity 96.9%), while lacking the NodB domain present in the latter. These facts suggested that the xynA and xynB genes originated from a common ancestral gene through gene duplication. XynA was purified from a recombinant Escherichia coli strain and characterized. The purified enzyme was highly active toward xylan; the specific activity on oat-spelt xylan was 689 units/mg protein. Immunological and zymogram analyses suggested that XynA and XynB are components of the C. thermocellum F1 cellulosome.

Amino Acid Sequence↗
PubMed1999

T3-hydrocortisone synergism on adult-type erythroblast proliferation and T3-mediated apoptosis of larval-type erythroblasts during erythropoietic conversion in Xenopus laevis.

The conversion of an erythropoietic system from larval to adult type in anuran amphibia may possibly come about through cell replacement. The hormonal regulation of apoptosis of larval-type precursor cells and adult-type cell proliferation has yet to be examined in detail. In amphibians, corticoids synergize T3 action during metamorphosis. In the present study, examination was made of the process of larval-to-adult conversion in the liver erythropoietic site of Xenopus laevis, with special attention to how these metamorphic hormones, T3 and corticoid, regulate programmed cell death specific for larval erythroblasts and the proliferation of adult cells. Immunohistochemical analysis of liver sections indicates that the number of larval erythroblasts decreased to less than 50% at the early climax stage (stages 59-60) of metamorphosis. Overall liver morphology greatly changed subsequent to the climax stage from the three-lobe to the two-lobe shape. The addition of T3 (10(-8) M) to premetamorphic tadpoles induced considerable liver morphological change and a 50% decrease in larval-type erythroblasts. These erythroblast decreases seem to take place through the apoptotic process, since double-staining experiments with in situ DNA nick-end labeling (TUNEL) and hemoglobin immunostaining revealed that DNA breakage of nuclei, a well-known feature of apoptosis, occurred specifically in larval erythroblasts during prometamorphosis. Hydrocortisone (HC), which modulates T3 action during metamorphosis, was found not to be a factor in larval cell decrease. But adult erythroblasts increased by 8 times as much through the action of T3 and 32 times as much by the action of T3 plus HC, indicating the important action of T3-HC synergism. It thus follows that the erythropoietic system is converted during metamorphosis effectively by two distinct hormonal mechanisms, T3-HC synergism on adult erythroblast proliferation and T3-mediated programmed death of larval precursor cells.

Animals↗
PubMed1999

Role of O-acetyl-l-serine in the coordinated regulation of the expression of a soybean seed storage-protein gene by sulfur and nitrogen nutrition.

The composition of seed storage proteins is regulated by sulfur and nitrogen supplies. Under conditions of a low sulfur-to-nitrogen ratio, accumulation of the beta-subunit of beta-conglycinin, a sulfur-poor seed storage protein of soybean (Glycine max [L.] Merr.), is elevated, whereas that of glycinin, a sulfur-rich storage protein, is reduced. Using transgenic Arabidopsis thaliana [L.] Heynh., it was found that the promoter from the gene encoding the beta-subunit of beta-conglycinin up-regulates gene expression under sulfur deficiency and down-regulates gene expression under nitrogen deficiency. To obtain an insight into the metabolic control of this regulation, the concentrations of metabolites related to the sulfur assimilation pathway were determined. Among the metabolites, O-acetyl-l-serine (OAS), one of the precursors of cysteine biosynthesis, accumulated to higher levels under low-sulfur and high-nitrogen conditions in siliques of transgenic A. thaliana. The pattern of OAS accumulation in response to various levels of sulfur and nitrogen was similar to that of gene expression driven by the beta-subunit promoter. Elevated levels of OAS accumulation were also observed in soybean cotyledons cultured under sulfur deficiency. Moreover, OAS applied to in-vitro cultures of immature soybean cotyledons under normal sulfate conditions resulted in a high accumulation of the beta-subunit mRNA and protein, whereas the accumulation of glycinin was reduced. These changes were very similar to the responses observed under conditions of sulfur deficiency. Our results suggest that the level of free OAS mediates sulfur- and nitrogen-regulation of soybean seed storage-protein composition.

Antigens, Plant↗
PubMed1999

Esophageal perforation and mediastinal abscess following placement of a covered self-expanding metallic stent and radiation therapy in a cancer patient.

Patients with advanced esophageal cancer may require intubation with a stent to relieve debilitating dysphagia. However, if these patients also undergo radiation therapy, they may incur esophageal injury, thus increasing the risk of perforation after placement of the stent. Herein we report the case of a 71-year-old man who received such combination therapy and died of severe sepsis 65 days after the stent was inserted. An autopsy revealed that the stent had perforated into the mediastinal pleura and that an abscess had developed around the perforation. We conclude that caution should be taken before combining radiation therapy with the use of a stent.

Abscess↗
PubMed1999

Repeat-directed isolation of a novel gene preferentially expressed from the maternal allele in human placenta.

Using a repetitive sequence of tandemly arrayed pentanucleotides in the human H19 3'-flanking region, we isolated a phage clone (lambda PEN11) which localized to chromosome 11p15.5. The lambda PEN11 phage encodes a 2.3-kb cDNA consisting of seven exons at least. The gene was mainly expressed in brain and pancreas (and less abundantly in testis), and demonstrated differential allele usage, with maternal expression being predominant in placenta, which indicates the gene is an atypical imprinted gene. While the pentamer repeat might contribute to this effect, it is also possible that the differential allele usage might reflect the local chromosomal structure known as the imprinting domain.

Alleles↗
PubMed1999

Effects of hepatocyte growth factor (HGF) and activin A on the morphogenesis of rat submandibular gland-derived epithelial cells in serum-free collagen gel culture.

To study the mechanisms of morphogenesis in salivary gland regeneration, we have established the RSMG-1 cell line derived from submandibular gland (SMG) of 10-wk-old Wistar female rats in serum-free culture. Our finding that RSMG-1 cells originated from duct cells was based on morphology and immunohistochemical results. In three-dimensional serum-free collagen gel culture, HGF induced branching morphogenesis of RSMG-1 cells. Histological examination revealed that HGF-induced branching structure exhibited well-formed lumina. This morphology closely resembles that found in vivo. The cells also expressed activin A. Exogenously added activin A at a high concentration reduced HGF-induced branching morphogenesis. These findings suggest that the morphogenesis of the salivary gland is modulated by HGF and activin A. Our results show that the RSMG-1 cell line may be useful in studies of salivary gland regeneration.

Activins↗
PubMed1999

The role of p53 in bleomycin-induced DNA damage in the lung. A comparative study with the small intestine.

To elucidate the role of p53 and apoptosis in the pathogenesis of lung injury, we examined histological changes, expressions of p53 and p21waf1/cip1 (p21), apoptosis, DNA double strand breaks, cell kinetics, and DNA synthesis in C57/BL6 mice (p53+/+) and mice deficient for p53 (p53-/-) at 2 hours to 7 days after a single intravenous administration of bleomycin. We also compared these parameters between the lung cells and small intestinal epithelial cells to explore potential differences in their response to DNA damage. Bleomycin induced p21 expression in a p53-dependent manner in p53+/+ mice but neither p53 nor p21 expression in p53-/- mice. In the lung of both groups of mice, focal inflammation followed by fibrosis was observed, but there was no evidence of apoptosis. Cells with DNA breaks and those undergoing DNA synthesis were unequivocally increased, but the cycling cell fraction remained unchanged, suggesting that the DNA synthesis detected in the lung reflected unscheduled DNA synthesis for repair of damaged DNA. DNA breaks and unscheduled DNA synthesis were prolonged in p53-/- mice compared to p53+/+ mice. By contrast, in the small intestine, marked cell cycle arrest and extensive apoptosis were evoked in the cycling crypt cells of both groups of mice, but these changes were milder and DNA breaks remained detectable for a longer time in p53-/- mice than in p53+/+ mice. Among the resting enterocytes in the villi, apoptosis was observed almost equally in both groups, but repair of DNA breaks was significantly delayed in the p53-/- mice. These observations imply that apoptosis is mediated largely by the p53-dependent pathway in the crypts but exclusively by the p53-independent pathway in the villi, that this pathway is particularly important in DNA repair in the villi, and that despite this difference in the significance of apoptosis, p53 plays an important role in DNA repair in both the crypts and villi. Our results suggest that the lung cells and small intestinal cells respond to the bleomycin treatment in different ways in terms of the induction of apoptosis and that p53 carries out an essential role in the early response to and repair of DNA damage by a non-apoptotic mechanism which appears to be crucial in the noncycling lung cells and enterocytes. Importantly, the p53-p21 pathway and apoptosis are unlikely to be essential for bleomycin-induced tissue injury in the lung.

Animals↗
PubMed1999

Basement membrane patterns, gelatinase A and tissue inhibitor of metalloproteinase-2 expressions, and stromal fibrosis during the development of peripheral lung adenocarcinoma.

To clarify the process and mechanisms of the development and progression of peripheral lung adenocarcinoma, we investigated the relationships among the patterns of basement membrane (BM), stromal fibrosis, and the expressions of gelatinase A and tissue inhibitor of metalloproteinases-2 (TIMP-2) in 33 lesions of atypical alveolar cell hyperplasia (AAH) and 48 lesions of lung adenocarcinoma, including 24 lesions of bronchioloalveolar carcinoma (BAC). We found that the architecture of alveolar BM was intact in all 33 AAH lesions and 11 nonsclerosing BAC lesions that formed no central scar, suggesting that these lesions are early-stage intraepithelial neoplasia. The preexistent BM of the lung was disrupted, and the BM components around the neoplastic glands were disrupted or absent in the area of the central scar of some sclerosing BAC lesions with collapse fibrosis alone (2 of 4) and in those of all of the adenocarcinoma lesions associated with desmoplastic stromal fibrosis (nine sclerosing BAC and 24 non-BAC tumors). These results suggested that, in lung adenocarcinomas, destruction of the BM was correlated with the formation of a central scar, particularly with desmoplasia. It is likely that adenocarcinomas with a central scar are advanced and invasive cancers potentially having metastatic activity. The expression of gelatinase A and TIMP-2 was associated with central scar formation as well as with destruction of the BM components. Both the neoplastic and stromal cells expressed gelatinase A and TIMP-2 and probably play a role in tumor cell invasion.

Adenocarcinoma↗
PubMed1999

Primary signet-ring cell carcinoma of the lung: histochemical and immunohistochemical characterization.

To establish criteria for differential diagnosis and to clarify the histogenesis of primary signet-ring cell carcinoma (SRCC) of the lung, five cases were studied by mucin-histochemical and immunohistochemical analyses and compared with SRCC of the gastrointestinal tract and mucus-producing adenocarcinoma of the lung. The proportion of signet-ring cell component varied from 10% to 90% in four cases, and the remaining tumor was a pure SRCC. Mucin-histochemistry showed a close similarity between lung SRCC and goblet cell-type or bronchial gland cell-type adenocarcinoma of the lung. Eighty percent of SRCCs showed positive immunoreactions for lactoferrin, a marker of bronchial gland cell differentiation, the results being consistent with the conclusions in previous studies that lung SRCC is closely related to bronchial gland cell-type adenocarcinoma. The incidence of K-ras mutation detected by the restriction fragment length polymorphism method was relatively high in lung SRCC (three of five) and goblet cell-type adenocarcinoma of the lung (four of four). Mucin-histochemistry indicated that lung SRCC has mucin production similar to that of the colon and colorectal-type SRCCs of the stomach but not to that of gastroduodenal-type SRCC of the stomach. Immunohistochemical staining for MUC-1 and MUC-2 glycoproteins showed a distinct difference; lung SRCC was positive for MUC-1 but negative for MUC-2, whereas colon SRCC and colorectal-type gastric SRCC were negative for MUC-1 but positive for MUC-2.Thus, by a combination of mucin-histochemistry and MUC-1 and MUC-2 immunohistochemistry, primary lung SRCC can be distinguished from metastatic lung SRCC originating in the gastrointestinal tract.

Adenocarcinoma↗
PubMed1999

Intraocular lens tilt and decentration, anterior chamber depth, and refractive error after trans-scleral suture fixation surgery.

OBJECTIVES: To compare the extent of intraocular lens (IOL) tilt and decentration, as well as the anterior chamber depth after trans-scleral suture IOL fixation after either secondary out-of-the-bag or primary in-the-bag IOL implantation. DESIGN: Retrospective, comparative, nonrandomized, interventional study. PARTICIPANTS: Fifty-two eyes that underwent scleral suture fixation were compared with 51 eyes that underwent secondary out-of-the-bag implantation and 50 eyes that underwent in-the-bag implantation. INTERVENTION: One-piece polymethyl methacrylate IOL implantation by three different techniques. MAIN OUTCOME MEASURES: The tilt angle and decentration length of the IOL, as well as the anterior chamber depth, were measured by the Scheimpflug videophotography system. The spherical equivalent error from the predicted value was also examined. RESULTS: The mean tilt angle in the scleral suture fixation group was significantly greater than that in either the out-of-the-bag or the in-the-bag implantation group (P<0.0001). The mean decentration length was also largest in the suture group, followed by the out-of-the-bag group and the in-the-bag group (P<0.0001). The anterior chamber depth in the suture group and the out-of-the-bag group was significantly smaller than that in the in-the-bag group (P<0.0001). The spherical equivalent error in the suture group and the out-of-the-bag group was also greater than that in the in-the-bag group (P<0.0001). CONCLUSIONS: The extent of both tilt and decentration after scleral suture fixation was greater than that observed after either out-of-the-bag or in-the-bag implantation. The anterior chamber depth with the sutured or out-of-the-bag fixated IOL was shallower than that with the in-the-bag fixated IOL, which resulted in a significant myopic shift.

Adolescent↗