Biomedical subjects

H Hayashida

Publications and source records attributed to H Hayashida.

At least 19 recordsLinked to original sources

PubMed1998

The complete nucleotide sequence of the human immunoglobulin heavy chain variable region locus.

The complete nucleotide sequence of the 957-kb DNA of the human immunoglobulin heavy chain variable (VH) region locus was determined and 43 novel VH segments were identified. The region contains 123 VH segments classifiable into seven different families, of which 79 are pseudogenes. Of the 44 VH segments with an open reading frame, 39 are expressed as heavy chain proteins and 1 as mRNA, while the remaining 4 are not found in immunoglobulin cDNAs. Combinatorial diversity of VH region was calculated to be approximately 6,000. Conservation of the promoter and recombination signal sequences was observed to be higher in functional VH segments than in pseudogenes. Phylogenetic analysis of 114 VH segments clearly showed clustering of the VH segments of each family. However, an independent branch in the tree contained a single VH, V4-44.1P, sharing similar levels of homology to human VH families and to those of other vertebrates. Comparison between different copies of homologous units that appear repeatedly across the locus clearly demonstrates that dynamic DNA reorganization of the locus took place at least eight times between 133 and 10 million years ago. One nonimmunoglobulin gene of unknown function was identified in the intergenic region.

Chromosomes, Artificial, Yeast↗

PubMed1998

Differentiation of clinical isolates of Actinobacillus actinomycetemcomitans using an insertion sequence, ISAa1.

We previously identified an IS200-like sequence (ISAa1) in the genome of Actinobacillus actinomycetemcomitans FDC Y4. One or more hybridizing bands to the ISAa1 probe were detected in each of several reference strains, representing three of the serotypes (a through c) of A. actinomycetemcomitans. In this study, we examined whether a restriction fragment-length polymorphism (RFLP) with ISAa1 as a probe could differentiate clinical isolates. One or more hybridizing bands were detected in each of the 27 strains examined, which could be divided into seven groups according to restriction fragment-length polymorphism pattern. Several strains were observed with identical restriction fragment-length polymorphism types but with different serotypes. Conversely, strains were also observed with differing restriction fragment-length polymorphism types and identical serotypes.

Adolescent↗

PubMed1998

[Tuberous sclerosis associated with renal angiomyolipoma, pulmonary lymphangioleiomyomatosis and subungual fibroma: report of a case].

We report a case of tuberous sclerosis associated with bilateral renal angiomyolipomas (AMLs), pulmonary lymphangioleiomyomatosis (LAM) and subungual fibroma of hands and feet. A 42-year-old woman who was diagnosed as tuberous sclerosis at the age of 18 complained of left flank pain and abdominal fullness. Bilateral renal AMLs were pointed out when complete examinations were performed for hypertension at the age of 32. She suffered from severe left flank pain and abdominal distension due to the left renal tumor. Left nephrectomy and excision of the renal hilar tumor were performed. The left renal tumor weighed 1120 g, the perirenal space was filled with the tumor. histopathological diagnosis of the left renal tumor and renal hilar tumor was AML. In our case, bilateral pneumothorax appeared, and chest CT scan revealed bilateral multiple pulmonary cysts. Histopathological diagnosis of pulmonary cysts was LAM. Other complications of our case are intracranial calcification and adenoma sebaceum.

Adenoma↗

PubMed1998

[Good response in case of hepatocellular carcinoma; a case report of interdisciplinary local therapy].

A 47-year-old male patient with chronic hepatitis had a high AFP level during the follow-up period. Abdominal CT revealed at S5, which led to a diagnosis of hepatocellular carcinoma. In August 1992, partial resection of S5 was performed, and ethanol was injected into the tumor at S2. In July 1993, recurrent tumors were observed at S5 and S3. PEIT was performed for each lesion. In December 1994, multiple recurrence was observed and 4 mg SMANCS was injected through the proper hepatic artery. In July 1995, another 4 mg of SMANCS was injected into the tumors. In June 1996, only a 20 mm lesion at S5 remained while the other lesions disappeared. Under general anesthesia, the patient underwent percutaneous microwave tumor coagulation. In December 1997, the AFP level was normal, and imaging revealed disappearance of the recurrent tumor. Selection of local therapy for hepatocellular carcinoma achieved long survival in our case considering the QOL and frequent therapy administration.

Antineoplastic Agents↗

PubMed1997

Cloning and sequencing of part of the S10 operon from Actinobacillus actinomycetemcomitans FDC Y4.

We have cloned and sequenced the 5.2 kb EcoRI fragment that contained part of the S10 operon from Actinobacillus actinomycetemcomitans FDC Y4. The order of the ribosomal protein genes was identical to that of the S10 operon of Haemophilus influenzae and Escherichia coli. The deduced amino acid sequences of ribosomal proteins in this operon displayed significant homologies (65.3%-100%) to those of H. influenzae, E. coli, Yersinia enterocolitica and Yersinia pseudotuberculosis. Phylogenetic trees obtained for these ribosomal proteins were similar to that obtained for 16S rRNA.

Aggregatibacter actinomycetemcomitans↗

PubMed1997

Transcriptional analysis of the groESL operon from Porphyromonas gingivalis.

Transcriptional analysis of the groESL operon from Porphyromonas gingivalis, one of the obligative anaerobic oral microorganisms implicated in adult periodontitis, was performed. P. gingivalis 381 cultured at 37 degrees C was shifted to 42 degrees C, 45 degrees C or 48 degrees C for 10 mins. Northern hybridization analysis revealed that a band with 2.1-kb (kilo base pair) was observed, and the transcripts increased greatly by heat shock. Primer extension and S1 mapping detected four different 5'-ending sites of the mRNAs at the upstream region of the groES. Three sites out of the four were heat-inducible. There were inverted repeats and a Escherichia coli sigma 32-recognizing consensus sequence in the promoter region of the groESL, which may be relevant to the regulation of transcription of groESL operon in P. gingivalis. Both a heat shock promoter and inverted repeats may be relevant to the transcriptional regulation of the groESL operon in P. gingivalis.

Bacterial Proteins↗

PubMed1997

Pelvic nerve stimulation-induced pressor responses in corpus cavernosum of anesthetized dogs.

To analyze the mechanism of penile erection and pathogenesis of impotence, pressures in the corpus cavernosum in anesthetized dogs were measured. Pelvic nerve stimulation produced pressor responses in a frequency-dependent manner. Intravenous injections of NG-nitro-L-arginine, a nitric oxide (NO) synthase inhibitor, dose dependently attenuated the response, and the inhibition was reversed by intravenous injection of L-arginine but not of D-arginine. The response was also inhibited by NG-nitro-L-arginine injected into the corpus cavernosum, the potency being approximately 10 times of that applied intravenously. The intracavernous injection of L-arginine restored the response. NG, NG-dimethylarginine, an endogenous NO synthase inhibitor, dose dependently attenuated the stimulation-induced response, which was restored by an intracavernous injection of L-arginine. An intravenous injection of hexamethonium abolished the pressor response to nerve stimulation, whereas phentolamine and atropine did not significantly alter the response. These findings suggest that an increase in intracavernous pressure caused by pelvic nerve stimulation in anesthetized dogs is mediated by NO liberated from postganglionic neurons that originate in the ganglion located in the vicinity of corpus cavernosum.

Animals↗

PubMed1997

[Hemo-lymphangioma of the scrotum: a case report].

A 3-year-old boy was referred because of a painless mass in the left scrotum. On palpation, the mass was discriminated from the testis, epididymis and spermatic cord and showed transillumination. A part of the mass was dark purple in color. Total surgical excision of the mass was performed. The lesion was multicystic (2-15 mm), adherent to the scrotal skin, and easily dissectable from the testicle. Pathological examination revealed lymphangioma as a major component and hemangioma as a minor part. He has been free of recurrent disease for 2 years. This is the 7th case of hemo-lymphangioma of the scrotum in the Japanese literature.

Child, Preschool↗

PubMed1996

Molecular analysis of a new insertion sequence from Actinobacillus (Haemophilus) actinomycetemcomitans FDC Y4.

We have found a new insertion sequence (IS), designated ISAa1, downstream of the S10 operon in Actinobacillus (Haemophilus) actinomycetemcomitans FDC Y4. ISAa1, the first IS element characterized in this organism, is 705 bp long and lacks terminal inverted repeats. This element displayed significant homology with IS200. Hybridization patterns of genomic DNA of seven A. actinomycetemcomitans strains with an internal ISAa1 probe varied depending on the serotypes, suggesting that ISAa1 might be a useful tool for epidemiological studies.

Aggregatibacter actinomycetemcomitans↗

PubMed1996

Bulky transitional cell carcinoma of bladder with inverted proliferation.

Two women, aged 51 and 62 years, had unusual transitional cell carcinomas of the urinary bladder which were > 5 cm and had a structural resemblance to inverted papilloma or Brunn's nest. They were treated by bladder-preserving surgery with no evidence of recurrence after 30 and 103 months follow-up, respectively. Our cases show some hitherto unrecognized aspects of transitional cell carcinoma with inverted proliferation because the tumors are usually found in males and tend to be aggressive.

Carcinoma, Transitional Cell↗

PubMed1996

Comparison of neurogenic contraction and relaxation in canine corpus cavernosum and penile artery and vein.

Functional roles of autonomic efferent nerves were compared in the isolated canine corpus cavernosum, penile artery and penile vein that participate in the penile erection by changing blood distribution. Nicotine produced moderate contraction in the arterial strips, but only a slight or no contraction in the corpus and venous strips. The contraction was suppressed or reversed to a relaxation by prazosin. Under alpha 1-adrenoceptor blockade, relaxations induced by nicotine were in the order of the corpus > artery > > vein. The response was abolished by NG-nitro-L-arginine (L-NA) and restored by L-arginine. The responses to nicotine and exogenous nitric oxide (NO) were abolished by oxyhemoglobin. The relaxant response to transmural electrical stimulation at 5 Hz was greater in the corpus than venous strips treated with prazosin, and it was abolished by L-NA. Contractions caused by nicotine under treatment with L-NA were greater in the artery than in the vein and corpus. Histochemical studies demonstrated nerve fibers containing NO synthase and tyrosine hydroxylase immunoreactivity in the corpus cavernosum, artery and vein. It is concluded that the canine corpus cavernosum, penile artery and penile vein are innervated by adrenergic, vasoconstrictor and nitroxidergic, vasodilator nerves; neurogenic vasodilatation is predominant in the corpus muscle, whereas neurogenic vasoconstriction predominates in the artery. Such a different functioning of the nerves may be responsible for the penile erection.

Adrenergic alpha-Antagonists↗

PubMed1996

Neurogenic nitric oxide mediates relaxation of canine corpus cavernosum.

PURPOSE: The aim of the present study is to analyze mechanisms underlying neurogenic relaxation of the corpus cavernosum which are believed to participate in penile erection. MATERIALS AND METHODS: Mechanical responses to nerve stimulation by electrical pulses and nicotine were measured in strips of canine corpus cavernosum precontracted with phenylephrine. Cyclic guanosine monophosphate (GMP) contents in the strips were also measured by radioimmunoassay. Immunohistochemistry for nitric oxide synthase (NOS) and vasoactive intestinal polypeptide (VIP) was performed. RESULTS: Transmural electrical stimulation and nicotine produced relaxations in the isolated canine corpus. The neurogenic relaxation was abolished by N omega-nitro-L-arginine, a NOS inhibitor, and the inhibition was reversed by L-arginine. Relaxations induced by nerve stimulation and exogenous nitric oxide (NO) were depressed by oxyhemoglobin and methylene blue. Vasoactive intestinal polypeptide (VIP)-induced relaxations were not influenced by these inhibitors. In the controls strips and those made unresponsive to VIP by its repeated application, the responses to nerve stimulation did not differ. The content of cyclic GMP in the tissue increased in response to nicotine, the effect being abolished by the NO synthase inhibitor. Immunohistochemical study demonstrated neurons containing NOS and VIP. CONCLUSIONS: It appears that the relaxation induced by nerve stimulation is mediated solely by NO liberated from the nerve that activates soluble guanylate cyclase and increases the production of cyclic GMP in smooth muscle, whereas VIP does not play a role in the regulation of muscle tone under the experimental conditions used.

Animals↗

PubMed1995

Interleukin-1 receptor antagonist modifies the changes in vital organs induced by acute necrotizing pancreatitis in a rat experimental model.

OBJECTIVE: Interleukin-1 (IL-1) is a mediator in some critical conditions such as septic shock and multiple organ failure. Acute pancreatitis is one of the noted causes of multiple organ failure but the mechanism by which local inflammation progresses to systemic disease is unknown. In this study, we used an IL-1 receptor antagonist (IL-1ra) to investigate whether multiple organ failure due to acute pancreatitis is mediated by IL-1, as in other causes such as severe infection, trauma, and major surgery. DESIGN: Prospective, randomized, controlled trial. SETTING: Research laboratory of a university medical school. SUBJECTS: Specific pathogen-free male Wistar rats weighing 200 to 250 g. INTERVENTIONS: Necrotizing pancreatitis was induced by retrograde injection of deoxycholate solution into the biliopancreatic duct. IL-1ra was injected intravenously at a dose of 10 mg/kg 15 mins before induction of acute pancreatitis and then infused continuously at a rate of 5 mg/kg/hr for the following 24 hrs. MEASUREMENTS AND MAIN RESULTS: Although treatment with recombinant human IL-1ra did not affect the degree of local pancreatic insult, it significantly reduced mortality, improved urine output as an indicator of the state of shock, and ameliorated the accumulation of neutrophils into the lung in a rat experimental pancreatitis model. CONCLUSIONS: We concluded that multiple organ failure in severe pancreatitis is mediated, at least in part, by IL-1 through the activation of neutrophils. Furthermore, we concluded that circulatory collapse may also be important in the mechanism of the lethal effect of pancreatitis.

Acute Disease↗

PubMed1995

Interleukin 10 reduces mortality from severe peritonitis in mice.

Interleukin 10 (IL-10) is known to suppress the induction of proinflammatory cytokines such as tumor necrosis factor (TNF) and IL-1 and is itself induced by monocytes and macrophages during sepsis. We studied the therapeutic efficacy of IL-10 by testing its effect on the survival rate in the murine cecal ligation-and-puncture (CLP) model. Administration of 1 microgram or more of recombinant murine IL-10 6 h after induction of sepsis decreased lethality in septic mice significantly and also suppressed the elevation of circulating TNF after sepsis. However, treatment with the same dose of IL-10 simultaneously or 6 h before induction of CLP had no effect on survival, and treatment with anti-TNF antibody after induction of CLP had no effect on the survival rate. These data suggest that cytokine modulation with IL-10 is a potential candidate for the treatment of sepsis and sepsis-related multiple organ failure.

Animals↗

PubMed1995

Changes in serum granulocyte colony-stimulating factor (G-CSF) and interleukin 6 (IL-6) after surgical intervention.

To evaluate the physiological role of G-CSF following surgery, we measured the serum levels of immunoreactive IL-6 and G-CSF sequentially in nine patients after major elective thoracoabdominal surgery for esophageal carcinoma. Both G-CSF and IL-6 levels reached their maxima at the first postoperative day and decreased thereafter. There was a significant correlation between serum G-CSF (y) and IL-6 (x) levels (y = 3.273x + 3.991; r = 0.787, n = 78, p < 0.001). In the case that developed aspiration pneumonia and ARDS at the second postoperative day, the measured G-CSF level was less than half the predicted value. The relationship between serum G-CSF and IL-6 levels supports the central role of G-CSF as the host defense response modifier and, thus, low G-CSF levels in the circulation is one reason for the immunodeficient state after major surgery.

Aged↗

PubMed1994

Cloning and sequencing of the groESL homologue from Porphyromonas gingivalis.

The homologue of groESL from Porphyromonas gingivalis was cloned and sequenced. Nucleotide sequencing suggested an operon containing two open reading frames (ORFs) homologous to groESL operon of Escherichia coli. The upstream ORF consisted of 267 bp corresponding to 89 amino acid residues. The downstream ORF consisted of 1635 bp corresponding to 545 amino acid residues.

Amino Acid Sequence↗

PubMed1994

Recent translocation of variable and diversity segments of the human immunoglobulin heavy chain from chromosome 14 to chromosomes 15 and 16.

We studied the organization and origin of three orphon regions, VH-F, D5-a, and D5-b, of the human immunoglobulin heavy-chain gene using yeast artificial chromosomes. VH-F and two D5 regions were mapped to chromosome bands 16p11 and 15q11-q12, respectively, by using human/rodent somatic cell hybrids and fluorescence in situ hybridization. No D5 segments were found on chromosome 14, in contradiction to previous reports. The VH-F region consists of 7 VH segments and encompasses 160 kb of DNA. A cluster of VH segments homologous to the VH-F region orphons was found in the region 245-430 kb (V2-26 to V3-11) upstream of the JH cluster on chromosome 14. Comparison of VH sequences between the VH-F and the chromosome 14 loci indicates that the translocation of the VH-F region took place, at the earliest, 20 x 10(6) years ago. The D5-a and D5-b regions were obtained in two independent contigs. The former contains only D segments in 140 kb of DNA, while the latter carries 3 VH segments downstream of D segments in 110 kb of DNA. V54, one of these VH orphon segments, is about 95% homologous to V1-18, which is located within the putative ancestor of the VH-F region on chromosome 14. Furthermore, the region detected by two DNA probes flanking the V54 segment was found only in the proximity of V1-18 within the 0.8-Mb VH region on chromosome 14. These results suggest that the two orphon loci on chromosomes 15 and 16 may have been translocated simultaneously.

Animals↗

PubMed1994

Comparison and evolution of human immunoglobulin VH segments located in the 3' 0.8-megabase region. Evidence for unidirectional transfer of segmental gene sequences.

Nucleotide sequences of 64 VH segments within the 3' 0.8-megabase region of the human immunoglobulin germ line VH locus were compared with trace evolution of human VH segments. Based on alignment of the deduced amino acid sequences of 37 functional germ line VH segments, a phylogenetic tree was generated using the neighbor-joining method. The phylogenetic tree clearly supports the previous classification of human VH segments into six families, which correlate roughly with mouse VH families with varying conservation. The human VH-III family is most homologous to mouse VH segments, suggesting that members of the VH-III family may be conserved by some functional constraint. The 5'-flanking region of each family has a family-specific structure. The sequenced 64 VH segments include 31 pseudogenes, of which 24 were highly conserved. Unidirectional transfer of segmental sequences was identified within the VH-III and VH-IV families, providing clear examples of germ line gene conversion. Such gene conversion may contribute to conserve structures of pseudo-VH segments. Comparison of the VH-IV family members indicates that recent repeated duplications and frequent gene conversions are responsible for strong conservation of this family, although functional selection is not completely excluded.

Amino Acid Sequence↗