Search PubMed⌕ Search

Biomedical subjects

Hiroshi Hashimoto

Publications and source records attributed to Hiroshi Hashimoto.

At least 37 records · Page 2Linked to original sources
PubMed2006

[Case in which landiolol hydrochloride improved left ventricular outflow tract obstruction with systolic anterior motion of the mitral valve following mitral valve plasty].

We report a case of left ventricular outflow tract (LVOT) obstruction caused by systolic anterior motion of the mitral valve (SAM) following mitral valve plasity (MVP). A 65-year-old man underwent mitral valve plasty for grade III mitral valve regurgitation. The plasty was done smoothly and the patient was weaned from cardiopulmonary bypass successfully with continuous dobutamine infusion. However, about 30 minutes after the weaning, severe cardiovascular collapse developed. Inotropic agent, such as dobutamine, ephedrine, or calcium hydrochloride was not effective. Trans-esophageal echocardiography (TEE) showed severe mitral valve regurgitation with LVOT obstruction due to SAM. The collapse was successfully treated with volume loading and a small amount of a beta1-adrenergic antagonist, landiolol hydrochloride. We conclude that acute LVOT obstruction with SAM could develop following MVP. TEE was a much useful tool for early diagnosis and landiolol hydrochloride would be a notable agent for nonsurgical treatment of LVOT obstruction with SAM.

Adrenergic beta-Antagonists↗
PubMed2006

[Clinical significance of cystoscopy in transrectal prostate biopsy].

The clinical significance of cystoscopy in patients with benign prostatic hyperplasia or prostate cancer remains open to discussion. We have always performed cystoscopy with prostate biopsy and have discovered bladder cancer in some patients. The present study investigated the clinical significance of performing cystoscopy with prostate biopsy. Subjects were 458 patients who underwent cystoscopy and ultrasound-guided transrectal prostate biopsy from January 1998 to December 2004. Mean age of subjects was 71.3 years (range, 52-93 years). Prostate biopsy was performed modified Eskews systematic 5-region prostate biopsy (12 core). Some abnormalities were found in 43 of the 458 patients (9.3%). Among these 43 patients, bladder cancer was found in 11 patients (2.4%), and transurethral resection bladder tumor (TUR-Bt) was performed on all 11 patients. Pathological staging of bladder cancer was pT1 and G2 in all cases. Bladder stones were seen in 13 patients (2.8%), benign bladder tumor in 5 patients (1.1%), urethral polyp in 7 patients (1.5%), urethral stenosis in 6 patients (1.3%) and ureteral stones associated with ureterocele in 1 patient (0.2%). Appropriate examinations and treatments were performed for all cases. Cystoscopy may be needed at the time of prostate biopsy because: the above-mentioned abnormalities were first discovered on cystoscopy; and the frequency of bladder cancer was 2.4% for the total patient population, and endoscopic surgery was performed.

Aged↗
PubMed2006

[Accidental use of suxamethonium for general anesthesia in a patient with hereditary hypocholinesterasemia that was not recognized preoperatively].

We experienced an accidental use of suxamethonium for general anesthesia in a 26-year-old woman with hereditary hypocholinesterasemia that had not been recognized preoperatively. The patient was scheduled for total colectomy as her chronic ulcerative colitis could not be controlled with medications. Routine preoperative screening such as blood cell counts, biochemical data, chest x-ray and electrocardiogram were performed but serum cholinesterase (ChE) activity was not measured. As the preoperative patient condition was good with no abnormal history, anesthesia was induced and maintained with propofol, ketamine and fentanyl as usual. For muscle relaxation, suxamethonium was used for tracheal intubation, and vecuronium was used for the maintenance. After surgery, postanesthetic course was uneventful. One year later, as the patient was pregnant and scheduled for cesarean section, the preoperative screening was done. The biological data showed a hypocholinesterasemia without liver dysfunction. Thus, previous medical records of internal medicine were cheked. Surprisingly the record showed hypocholinesterasemia when she was 15 and 21 years of ages. However, as the physicians did not recognize hypocholinesterasemia, they did not inform the patient of it. Why did the patient have no prolonged apnea and emergence after the previous anesthesia? As the surgical time was exceeded 4 hrs, plasma suxamethonium could fortunately be less than its effective concentration at emergence. However, this case strongly suggests us that preoperative screening should be done without any omission. In addition, if serum ChE activity is not examined, use of suxamethonium should be avoided.

Adult↗
PubMed2006

Analysis of the differences in structural chromosomal aberrations of the gastric mucosa between H. pylori positive and negative gastric cancer patients: involvement of H. pylori in the onset of gastric cancer and examination of the mechanism in gastric carcinogenesis following H. pylori eradication.

Gene mutations are essential to carcinogenesis. If an evident difference is observed in gastric mucosal chromosomal structure aberrations between H. pylori (Hp)-negative and Hp-positive gastric cancer patients, it may be interpreted as suggesting the involvement of Hp in gene mutations. This study was undertaken to compare chromosomal structural aberrations between Hp-negative and Hp-positive gastric cancer patients and to evaluate the effects of Hp eradication on chromosomal structures in clinical cases. The subjects of this study were 40 patients with gastric cancer divided into four groups: Group A was composed of 12 patients with Hp-negative gastric cancer (well-differentiated gastric cancer in 5 cases and poorly-differentiated in 7 cases), Group B of 8 patients with Hp-negative gastric cancer following Hp eradication (well-differentiated in 4 case and poorly-differentiated in 4 cases), Group C of 13 patients with Hp-positive gastric cancer (well-differentiated in 7 cases and poorly-differentiated in 6 cases) and Group D of 7 patients with gastric cancer (well-differentiated in 5 cases and poorly-differentiated in 2 cases) undergoing Hp eradication at subtotal gastrectomy. In each of the groups A, B and C, the structural chromosomal aberration such as loss of heterozygosity (LOH) and microsatellite instability (MSI) was analyzed. In Group D, changes in structural chromosomal aberrations after Hp eradication as compared to the pre-eradication structures were also analyzed. LOH and MSI were examined by PCR, using DNA extracted from the cancer-affected and intact gastric mucosal tissue specimens from each patient. In A, B and C groups, structural chromosomal aberrations were noted, and these aberrations tended to be more marked in cases of poorly-differentiated gastric cancer in each group. In terms of structural chromosomal aberrations, there was no marked difference between Group A and either Group B or C. Hp eradication resulted in no change in chromosomal structure as compared to the pre-eradication structure in Group D. These results suggest the possibility that Hp eradication does not affect chromosomal structures and Hp is involved in gastric carcinogenesis as an additive environmental factor rather than as a factor acting at the gene level.

Anti-Bacterial Agents↗
PubMed2006

[Histological investigation of prostate cancer treated with hormonal agents].

The histological diagnosis of prostate cancer treated with hormonal agents is often difficult because of various morphological changes induced by androgen ablation. Immunostaining of cytokeratins may be useful to prevent the underdetection of cancer cells. We examined prostatic specimens with histological diagnosis of 11 pTO patients who had undergone neoadjuvant endocrine therapy followed by radical prostatectomy. Anti-cytokeratin antibody, AE1/AE3 was used to detect the prostatic epithelial cells. Anti-cytokeratin antibody, 34/3 E12 was used to detect the prostatic basal cells. The loss of basal cells indicates the acini to be cancer. The immunostaining with these antibodies revealed that 2 out of 11 cases had residual cancer and were not pTO. The immunostaining of cytokeratins was useful to detect the residual prostatic cancer after endocrine therapy.

Aged↗
PubMed2006

[Indication of repeat prostate biopsy for the diagnosis of prostate cancer].

There is no standard criterion for repeat prostate biopsy in cases with a negative initial biopsy. We retrospectively analyzed our experience of repeat prostate biopsy to establish its indication for the diagnosis of prostate cancer. From April 1997 to March 2005, 35 consecutive patients underwent repeat prostate biopsy at the department of Urology, Asahikawa Medical College Hospital because of clinically suspicious prostate cancer despite a negative initial biopsy. We compared patients' age, number of cores obtained during repeat biopsy, digital rectal examination findings, total prostate volume, the time from the first to the last biopsy, total prostate specific antigen (PSA) value, free PSA/total PSA ratio, PSA density and PSA velocity between cancer-positive and cancer-negative groups. Prostate cancer was detected in 17 of 35 patients (49%). Fifteen patients with prostate cancer were diagnosed by the first repeat biopsy and other 2 patients were diagnosed by the second repeat biopsy. A statistically significant difference was only noted in age and PSA density. Persistently elevated total PSA and a higher PSA density in cases with a negative initial biopsy might be a good indication of repeat prostate biopsy for the diagnosis of prostate cancer.

Age Factors↗
PubMed2005

Elastofibroma: clonal fibrous proliferation with predominant CD34-positive cells.

Elastofibroma is a rare fibrous lesion that most commonly occurs in periscapular soft tissues and is characterized by accumulated abnormal elastic fibers. Although the lesion is generally regarded as a reactive process, an unusual fibroblastic pseudotumor, or as a fibroelastic tumor-like lesion, its etiology remains largely unknown. Recent cytogenetic demonstrations of chromosomal instability and some recurrent or clonal chromosomal changes have raised the possibility that the lesion represents a neoplastic process. We analyzed 14 cases of elastofibroma to further explore, morphologically and genetically, the characteristics of its cellular composition. The interspersed spindle or stellate cells showed a fibroblast-like appearance and were almost consistently positive for vimentin and frequently positive for CD34 and lysozyme immunohistochemically. No spindle cells of myofibroblastic phenotype were recognized. To assess the clonality of the lesions in female patients, the X-linked polymorphic human androgen receptor gene assay was performed using formalin-fixed, paraffin-embedded tissues. A nonrandom inactivation of the androgen receptor gene was detected in two informative cases. Thus, these findings suggest that CD34-positive mesenchymal cells are an integral component of elastofibroma, which represents a clonal fibrous proliferation.

Aged↗
PubMed2005

The first crystal structure of a family 31 carbohydrate-binding module with affinity to beta-1,3-xylan.

Here, we present the crystal structure of the family 31 carbohydrate-binding module (CBM) of beta-1,3-xylanase from Alcaligenes sp. strain XY-234 (AlcCBM31) determined at a resolution of 1.25A. The AlcCBM31 shows affinity with only beta-1,3-xylan. The AlcCBM31 molecule makes a beta-sandwich structure composed of eight beta-strands with a typical immunoglobulin fold and contains two intra-molecular disulfide bonds. The folding topology of AlcCBM31 differs from that of the large majority of other CBMs, in which eight beta-strands comprise a beta-sandwich structure with a typical jelly-roll fold. AlcCBM31 shows structural similarity with CBM structures of family 34 and family 9, which also adopt structures based on immunoglobulin folds.

Alcaligenes↗
PubMed2005

Structural mechanism for coordination of proofreading and polymerase activities in archaeal DNA polymerases.

A novel mechanism for controlling the proofreading and polymerase activities of archaeal DNA polymerases was studied. The 3'-5'exonuclease (proofreading) activity and PCR performance of the family B DNA polymerase from Thermococcus kodakaraensis KOD1 (previously Pyrococcus kodakaraensis KOD1) were altered efficiently by mutation of a "unique loop" in the exonuclease domain. Interestingly, eight different H147 mutants showed considerable variations in respect to their 3'-5'exonuclease activity, from 9% to 276%, as against that of the wild-type (WT) enzyme. We determined the 2.75A crystal structure of the H147E mutant of KOD DNA polymerase that shows 30% of the 3'-5'exonuclease activity, excellent PCR performance and WT-like fidelity. The structural data indicate that the properties of the H147E mutant were altered by a conformational change of the Editing-cleft caused by an interaction between the unique loop and the Thumb domain. Our data suggest that electrostatic and hydrophobic interactions between the unique loop of the exonuclease domain and the tip of the Thumb domain are essential for determining the properties of these DNA polymerases.

Amino Acid Sequence↗
PubMed2005

Extensive polymorphisms of LILRB1 (ILT2, LIR1) and their association with HLA-DRB1 shared epitope negative rheumatoid arthritis.

Leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1/LIR1/ILT2) is an inhibitory receptor broadly expressed on leukocytes and recognizes HLA-class I and human cytomegalovirus UL18. LILRB1 is encoded within the leukocyte receptor complex on 19q13.4, previously implicated to be a susceptibility region to systemic lupus erythematosus (SLE). In this study, we screened for polymorphisms of LILRB1 and examined their association with SLE and rheumatoid arthritis (RA). In the 5' portion of LILRB1, three haplotypes containing four non-synonymous substitutions within the ligand-binding domains and two single nucleotide polymorphisms within the promoter region were identified and designated as PE01-03. In the 3' portion, two haplotypes (CY01, 02) containing a non-synonymous substitution of the cytoplasmic region were identified. CY01 and 02 did not co-segregate with PE01-03. Significant association with susceptibility to SLE or RA was not observed; however, among the subjects not carrying RA-associated HLA-DRB1 shared epitope (SE), LILRB1.PE01/01 diplotype was significantly associated with RA (odds ratio 2.05, P = 0.019 and Pc = 0.038). Gross difference was not observed in the crystal structures, thermostabilities and binding affinities to HLA-class I ligands among LILRB1.PE01-03 haplotype products; however, surface expression of LILRB1 was significantly decreased in lymphocytes and monocytes from the carriers of PE01 haplotype. These findings demonstrated that LILRB1 is highly polymorphic and is associated with susceptibility to RA in HLA-DRB1 SE negative subjects, possibly by insufficient inhibitory signaling in leukocytes. In addition, these observations suggested that the polymorphisms of LILR family members may be substantially involved in the diversity of human immune responses.

Adult↗
PubMed2005

Whole genome association study of rheumatoid arthritis using 27 039 microsatellites.

A major goal of current human genome-wide studies is to identify the genetic basis of complex disorders. However, the availability of an unbiased, reliable, cost efficient and comprehensive methodology to analyze the entire genome for complex disease association is still largely lacking or problematic. Therefore, we have developed a practical and efficient strategy for whole genome association studies of complex diseases by charting the human genome at 100 kb intervals using a collection of 27,039 microsatellites and the DNA pooling method in three successive genomic screens of independent case-control populations. The final step in our methodology consists of fine mapping of the candidate susceptible DNA regions by single nucleotide polymorphisms (SNPs) analysis. This approach was validated upon application to rheumatoid arthritis, a destructive joint disease affecting up to 1% of the population. A total of 47 candidate regions were identified. The top seven loci, withstanding the most stringent statistical tests, were dissected down to individual genes and/or SNPs on four chromosomes, including the previously known 6p21.3-encoded Major Histocompatibility Complex gene, HLA-DRB1. Hence, microsatellite-based genome-wide association analysis complemented by end stage SNP typing provides a new tool for genetic dissection of multifactorial pathologies including common diseases.

Arthritis, Rheumatoid↗
PubMed2005

Structural characterization of calcineurin B homologous protein 1.

Calcineurin B homologous protein 1 (CHP1), also known as p22, is a calcium-binding EF-hand protein that plays a role in membrane trafficking. It binds to multiple effector proteins, including Na(+)/H(+) exchangers, a serine/threonine kinase, and calcineurin, potentially modulating their function. The crystal structure of calcium-bound CHP1 from rat has been determined at 2.2 Angstroms of resolution. The molecule has a compact alpha-helical structure containing four EF-hands. The overall folding topology of the protein is similar to that of the regulatory B subunit of calcineurin and to that of calcium- and integrin-binding protein. The calcium ion is coordinated in typical fashion in the third and fourth EF-hands, but the first and second EF-hands contain no calcium ion. The first EF-hand is maintained by internal interactions, and the second EF-hand is stabilized by hydrophobic interactions. CHP1 contains a hydrophobic pocket on the opposite side of the protein to the EF-hands that has been implicated in ligand binding.

Amino Acid Motifs↗
PubMed2005

Crystallization and preliminary X-ray crystallographic analysis of rat calcineurin B homologous protein 1.

Calcineurin B homologous protein 1 (CHP1), also known as p22, is a calcium-binding protein that plays a role in membrane trafficking and binds to multiple effector proteins, including Na+/H+ exchangers, serine/threonine protein kinase and calcineurin, potentially modulating their function. CHP1 has been crystallized at 277 K using polyethylene glycol as a precipitant. The crystal belongs to space group P2(1), with unit-cell parameters a = 55.5, b = 38.5, c = 90.0 A, beta = 90.7 degrees. A full set of diffraction data was collected to 2.2 A resolution at 100 K using the Photon Factory synchrotron-radiation source.

Animals↗
PubMed2005

Spinal epithelioid hemangioendothelioma with epithelioid angiosarcomatous areas.

Epithelioid hemangioendothelioma is a distinctive vascular tumor rarely involving bones. We report a case of epithelioid hemangioendothelioma in the cervical spine with angiosarcomatous areas. A 50-year-old female presented with dizziness while walking. A mixed sclerotic and osteolytic or destructive lesion was radiographically disclosed in her upper cervical vertebrae. Histologically, a laminectomy specimen exhibited areas of ordinary epithelioid hemangioendothelioma together with foci of more atypical epithelioid cell proliferation, closely resembling epithelioid angiosarcoma. This phenomenon has been exceptionally described in cases with skeletal lesions, which are typically of low-grade malignancy.

Biopsy↗
PubMed2005

Length variation of CAG/CAA triplet repeats in 50 genes among 16 inbred mouse strains.

CAG repeats coding for poly-glutamines have been studied by many groups as repeat length variations contributes to differences in protein function and disease outcome. In this study, we systematically searched public databases for genes carrying CAG repeats. For the genes obtained, we experimentally analyzed variations of length and the purity of the repeats in 62 loci among 16 inbred mouse strains, including wild-derived and laboratory strains. We found that length was conserved in 50% of the loci, especially among wild-derived strains. Of 496 polymorphic repeat alleles, 78% were uninterrupted and 22% were interrupted with non-CAG codons. Interruptions tended to occur in longer repeats and all repeats of greater length than 23 were interrupted. Although interruptions can act as suppressors for the expansion of CAG repeats, we found that the occurrence of the interruptions depended on the length of the CAG repeats. Furthermore, most poly-glutamines examined in this study existed in human orthologous genes, reflecting the functional significance of poly-glutamines in proteins.

Alleles↗
PubMed2005

Angiosarcoma of the scalp treated with curative radiotherapy plus recombinant interleukin-2 immunotherapy.

PURPOSE: To evaluate the effectiveness of curative radiotherapy (RT) plus recombinant interleukin-2 (rIL-2) immunotherapy regarding the treatment results for angiosarcoma of the scalp. Curative resection of angiosarcoma of the scalp is usually difficult because of the diffuse, clinically undetectable local spread. RT is a rational therapeutic approach, because a wide region of the dermis can be treated, while sparing the underlying normal tissues. Recently, the effectiveness of immunotherapy with rIL-2 has also been reported in the treatment of angiosarcoma of the scalp. METHODS AND MATERIALS: The data of 20 patients with angiosarcoma of the scalp treated with curative RT plus rIL-2 immunotherapy between January 1988 and June 2002 were retrospectively analyzed. The total radiation dose was 70.3 +/- 6.9 Gy. The fractions were 2-3 Gy daily, given 5 d/wk. rIL-2 immunotherapy was performed by transcatheter arterial administration in 10 patients, systemic administration in 11 during the course of RT, and intratumoral injection in 10 during and/or after RT; 12 patients received a combination of two. Five patients underwent limited surgery, and concomitant pacilitaxel chemotherapy was also used in 2 patients. RESULTS: The median survival time for overall, local recurrence-free, and distant metastasis-free survival was 36.2, 11.1, and 17.8 months, respectively. Local recurrence developed in 7 patients (35%), 4 of whom also had evidence of distant metastases. An additional 7 patients (35%) developed distant metastases alone. Recurrence within the radiation field was recognized in 2 patients with systemic rIL-2 administration alone (p < 0.05). Arterial or intratumoral administration combined with systemic administration of rIL-2 resulted in better distant metaststasis-free survival rates (p < 0.05). CONCLUSION: Curative RT plus rIL-2 immunotherapy provided an efficient, effective means of treating angiosarcoma of the scalp. Arterial or intratumoral administration combined with systemic administration of rIL-2 may prolong survival. Additional studies with detailed treatment protocols are recommended.

Aged↗
PubMed2005

Regular use of H2 blockers reduces the efficacy of roxatidine to control gastric pH and volume.

PURPOSE: H(2) antagonist premedication is common in surgical patients to control gastric pH and volume. However, several reports suggest that long-term medication may produce tolerance. Therefore, we studied the efficacy of a preanesthetic H(2) antagonist (oral roxatidine) in patients on regular H(2) antagonist therapy. METHODS: Forty-eight patients undergoing elective surgery were studied and grouped according to medication: those on no medication (control group) and those receiving H(2)-antagonists for less than two weeks (< or =2 w group), between two and four weeks (2-4 w group) and for longer than four weeks (> or =4 w group; n =12 each). All patients were given oral roxatidine as anesthetic premedication. Gastric volume and pH were measured after induction of anesthesia. Arterial blood was simultaneously collected for measurement of plasma gastrin levels using an enzyme-linked immunosorbent assay RESULTS: We observed a significant decrease and increase in, respectively, gastric pH and volume (mL) in the < or =2 w group [6.50 +/- 0.43 (NS) and 11.6 +/- 10.3 (NS)], 2-4 w group [4.77 +/- 2.11 (P < 0.01) and 14.1 +/- 10.8 (P < 0.05)], > or =4 w group [2.32 +/- 1.46 (P < 0.01) and 22.2 +/- 14.2 (P < 0.01)] compared to patients in the control group (6.35 +/- 1.32 and 4.9 +/- 4.7). Plasma gastrin levels were decreased with increasing time on medication with a significant difference (46%) observed after two weeks' treatment. In addition, there was a significant correlation between gastric pH and plasma gastrin levels (r = 0.43, P < 0.01). CONCLUSION: These data suggest that regular H(2) antagonist treatment for longer than two weeks may produce tolerance to pre-anesthetic H(2) antagonist administration.

Aged↗