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Biomedical subjects

S Akagi

Publications and source records attributed to S Akagi.

At least 19 recordsLinked to original sources
PubMed2005

Brown-Séquard-plus syndrome due to stab injury: a case report.

STUDY DESIGN: Case report. OBJECTIVE: To describe the mechanism of injury in this case and its clinical features. Magnetic resonance (MR) images of hemorrhage in spinal cord injury due to stab wound are discussed. METHODS: We describe the case of a 21-year-old woman who was stabbed in the right side of her neck and developed left-sided Brown-Séquard syndrome plus loss of bilateral proprioceptive sensation. Neither plain radiographs nor computed tomography of the cervical spine demonstrated any foreign bodies or fractures of the cervical spine. T2-weighted cervical MR images confirm spinal cord hemiresection at C5-C6. RESULTS: MR imaging was performed serially at 4 days, 4 weeks, and 8 weeks after trauma. The signal pattern of the spinal cord at the site of injury varied iso, iso, and low on T1-weighted consecutive images. Meanwhile, high signal intensity on T2-weighted images was consistent during the 8 weeks after incidence of trauma. A T2-weighted sagittal image showed a tiny spot of low intensity in the high signal band at the site of penetration, demonstrating hemosiderin formation in the spinal cord. The patient was treated conservatively and, recovered from Frankel grade C to grade D. CONCLUSION: Spinal cord injuries (SCI) following stab wounds are rare. MR imaging is definitely useful for recording and monitoring the pathology of SCI.

Adult↗
PubMed2004

Threonine metabolism in Japanese quail liver.

In general, threonine is metabolized by reaction catalyzed by threonine-3-dehydrogenase (TDH), threonine dehydratase (TH) or threonine aldolase (TA). The activities of these three enzymes were compared in the liver of Japanese quails and rats. The animals were fed a standard or threonine rich-diet, or fasted for 3 days. The specific activity of TDH in the liver from quail fed a standard diet was 11 times higher than that in the liver from rats fed a standard diet. The TDH activities in the livers of the fasting and 5% threonine-rich diet groups of quail were 3 and 2 times higher than those in the livers from quail fed the standard diet, respectively. The TH activity in the liver of rats fed a standard diet was 14 times higher than that in the liver of quail fed a standard diet. The TH activity in the rat liver after fasting was 2.3 times higher than that of the standard diet control. The activity of TA in the livers of rat and quail were so low that its role in threonine metabolism in both animals seemed to be negligible. These results suggest that threonine is a ketogenic amino acid in the quail liver, while it is a glucogenic in the rat liver.

Alcohol Oxidoreductases↗
PubMed2004

Effects of re-immunization of heifers against inhibin on hormonal profiles and ovulation rate.

To study the effect of re-immunization against inhibin on ovarian response and hormonal profiles, Japanese beef heifers (n = 5) were re-immunized three times with inhibin vaccine (recombinant ovine inhibin alpha-subunit in oil emulsion, 125 microg ml(-1)) one year after the primary immunization. Control heifers (n = 5) were injected with placebo (Montanide: Marcol adjuvant alone). Oestrous cycles were synchronized by using prostaglandin F2alpha (PGF2alpha) and ovarian response was monitored daily by ultrasonography. Blood samples were collected by jugular venipuncture for assessment of hormonal levels and inhibin antibody titres. In contrast to controls, inhibin re-immunized heifers generated antibodies against inhibin rapidly reaching a peak level 9 days after the first booster injection. The mean concentrations of FSH in re-immunized cows increased significantly in comparison with controls. In addition, there was a significant increase in oestradiol-17beta and progesterone levels in re-immunized cows compared with controls. Inhibin re-immunized heifers had a significant increase in small (> or =4 < 7 mm), medium (> or =7 < 10 mm) and large (> or =10 mm in diameter) sized follicles. Moreover, the mean ovulation rate was 5.0 +/- 1.1 after the third booster injection in re-immunized heifers compared with control heifers (single ovulation). These results clearly demonstrate that re-immunization of inhibin can be used to enhance ovarian follicular development and ovulation rate. Furthermore, the great number of follicles is a potential source of oocytes that could be harvested for in vitro fertilization and embryo transfer programmes.

Animals↗
PubMed2003

Threonine is the best substrate for D-lactate formation in octopus tentacle.

Carbon sources for D-lactate and enzyme activities related to D-lactate formation were investigated using cell-free homogenates of Octopus vulgaris tentacle tissue. The results are as follows: a) The best precursor for D-lactate formation was threonine and second best precursors were glycine and fructose-1,6-bisphosphate. Threonine and glycine served as precursors only in presence of glutathione. b) Both amino acids were precursors for methylglyoxal from which D-lactate was synthesized. Alanine, cysteine and serine were not precursors. We present a metabolic map for D-lactate formation in octopus in order to explain these experimental results.

Animals↗
PubMed2001

Co-infection by serologically-silent hepatitis B virus may contribute to poor interferon response in patients with chronic hepatitis C by down-regulation of type-I interferon receptor gene expression in the liver.

Intrahepatic mRNA levels of type-I interferon (IFN) receptor genes have been shown to correlate with the clinical efficacy of IFN therapy in patients with chronic hepatitis C. Recently, co-infection by serologically-silent hepatitis B virus (HBV) has been assumed to be associated with the poor IFN response in patients with chronic hepatitis C. The aim of this study was to investigate the relationship between the co-infection of serologically-silent HBV and type-I IFN receptor gene expression in the liver of patients with chronic hepatitis C. The intrahepatic mRNA levels of IFNAR2, one of the two subunits of the type-I IFN receptor, were quantified and compared with both the prevalence of HBV DNA and the hepatitis C virus (HCV) genotype in 45 patients with chronic hepatitis C, who were negative for hepatitis B surface antigen. Co-infection, as evaluated by a nested polymerase chain reaction, was present in 22 patients (48.9%), with dominance of the HCV genotype 1b (65.2%) over genotype 2a (31.8%). Co-infection was associated with lower IFNAR2 mRNA levels, higher levels of serum HCV RNA, and a poor IFN response, regardless of the HCV genotype. The findings suggest the possibility that co-infection by serologically-silent HBV is one of the factors that can lead to an unfavorable IFN response in chronic hepatitis C by down-regulation of IFN receptor gene expression in the liver.

Adult↗
PubMed2001

Gut transit time after ileal pouch-anal anastomosis using a radiopaque marker.

PURPOSE: The aim of this study was to determine the contribution of gastrointestinal motility to bowel function and the pathogenesis of pouchitis after ileal pouch-anal anastomosis. METHODS: Gastrointestinal transit time was assessed by a radiopaque marker technique in 32 patients with ulcerative colitis. RESULTS: Small intestinal transit time and pouch emptying time were 4.1 +/- 2 hours and 4.1 +/- 2.5 hours, respectively. There was no significant difference in pouch emptying time between patients with and without pouchitis. When only patients with acute pouchitis that responded to metronidazole were analyzed, there was a trend toward a prolonged pouch emptying time compared with those without pouchitis (P = 0.095). Whole gut transit time was inversely correlated with 24-hour stool frequency in patients without pouchitis (r = -0.63, P < 0.005). In the analysis of regional transit time, only small intestinal transit time was inversely correlated with 24-hour stool frequency (r = -0.472, P < 0.05). Significant prolongation of small intestinal transit time was demonstrated in patients over a period of 41 months (the median time) after ileostomy closure compared with those whose pouches had been functioning for 6 to 41 months (5.4 +/- 1.7 hours vs. 3.1 +/- 1.3 hours, P < 0.005). CONCLUSIONS: There was an association between small intestinal motility and bowel frequency. Further investigation is necessary in the pathogenesis of acute pouchitis regarding the relationship between delayed pouch emptying and subsequent development of mucosal inflammation.

Adolescent↗
PubMed2001

Sclerosing cholangitis and systemic lymphadenopathy.

A 48-year-old man was admitted to our hospital with jaundice and systemic lymphadenopathy. Cholangiographic findings and liver histology disclosed the presence of sclerosing cholangitis. The patient also had a marked polyclonal increase in IgG levels. The cholangiographic findings, the systemic lymphadenopathy, and the increase in IgG levels resolved completely after treatment with prednisolone. This case suggests that there is an association between sclerosing cholangitis and immunologic abnormalities, and that corticosteroid treatment is useful for this disorder.

Cholangitis, Sclerosing↗
PubMed2001

Analysis of expressed sequence tags from a cDNA library of somatic nuclear transfer-derived cloned bovine whole foetus.

The expression profile of genes in specific tissues is studied through analysing expressed sequence tags (ESTs) and provides useful information for characterizing gene function and tissue physiology. Analysis of ESTs is achieved by partial sequencing and characterization of clones isolated randomly from cDNA libraries. In the present study, we analysed the genes expressed in the somatic nuclear transfer-derived cloned bovine foetus in the early period of foetal development. To this aim, we constructed a directionally cloned cDNA library from somatic nuclear transfer-derived cloned 60 day-old whole foetus of cattle and sequenced 3' end of 510 randomly isolated clones. By BLASTN analysis, we identified 403 unique clones: 186 showed homology to previously identified genes, 123 matched uncharacterized ESTs and 94 showed no significant matches to sequences already present in DNA databases. Analysis of these cDNA clones revealed that this library contained a variety of functional genes, while foetuin, insulin-like growth factor 2, collagen type I alpha I and maternal G10 transcript genes were the most abundant transcripts. Our study allowed the establishment of a first list of genes expressed in bovine whole foetus. In future, the list of genes might help facilitate the understanding of physiology of foetal development in somatic nuclear transfer-derived cloned bovine foetus.

Animals↗
PubMed2001

Production and endocrine role of inhibin during the early development of bull calves.

This study investigated the ontogeny of control of FSH secretion by inhibin during early prepubertal development of bulls by 1) measurements of circulating levels of inhibin and FSH from 1 to 13 wk of age, and 2) immunoneutralization of endogenous inhibin at 7, 21, 60, and 120 days of age. In addition, production and localization of inhibin in testes were examined by immunohistochemistry and Western blots at 7, 21, 60, and 120 days of age. Plasma immunoreactive inhibin levels were relatively low between 1 and 3 wk of age and then showed a tendency to rise (P < 0.1) from 4 wk of age. Circulating concentrations of FSH were low during 3 wk after birth and increased at 5 wk, remained high (P < 0.05) until 16 wk of age. Treatment with inhibin antiserum resulted in a significant (P < 0.05) increase in plasma FSH at 7, 21, 60, and 120 days of age compared to those following injection of control serum; however, the magnitude of the FSH rise after inhibin immunization was greater as bulls aged. There were no significant changes in plasma LH after inhibin immunization. An intense staining of inhibin alpha subunits was found in Sertoli cells within the solid seminiferous cords from 7 to 120 days of age, while no specific immune reaction was found in interstitial cells. Western blot analysis of testicular homogenates isolated from bulls 7-120 days of age revealed presence of a 28.5-kDa molecule that cross-reacted with inhibin alpha subunit and beta(B) subunit-specific antibodies. In this study, before 13 wk of age in bull calves, there was no inverse relationship between plasma concentrations of immunoreactive inhibin and FSH. However, the present immunization study clearly indicates that inhibin participates in the regulation of FSH secretion from infancy to early prepubertal stage, although the endocrine significance of inhibin becomes greater in older bulls. The results also indicate that the major production site of inhibin in the testis is Sertoli cells and that these cells produce inhibin that exerts a negative feedback effect on FSH secretion from early stages of development.

Aging↗
PubMed2001

Clinical relevance of precore and basal core promoter variants of hepatitis B virus during natural hepatitis B e antigen seroconversion may be overstated.

BACKGROUND: Clinical relevance of nucleotide changes in precore and basal core promoters in the hepatitis B virus genome during hepatitis B e antigen seroconversion may be overstated. The authors investigated the existence and changes in the relative proportion of variants to wild virus that occur with seroconversion. METHODS: Sera from 30 school-aged long-term hepatitis B virus carriers, including 11 tested before and after seroconversion during 1 to 8 years of follow-up, were evaluated for variations in nucleotide sequences of the basal core promoter (T1762 and A1764), precore region (A1869), and carboxyl-terminus of the X region of the hepatitis B virus genome using an amplification refractory mutation detection system with mutant-specific primers. RESULTS: All variants were found to already exist before seroconversion at various wild-type/mutant ratios. The positive rates of these variants were not changed with loss of hepatitis B e antigen. Although there was a relative increase in the concentration of these mutants in wild-type/mutant mixed populations, most patients with only a wild-type population maintained the same pattern after loss of hepatitis B e antigen. CONCLUSIONS: Our results indicate that hepatitis B virus exists as a quasi species, and correlations of nucleotide sequences with clinical and serologic findings must be done with caution.

Adolescent↗
PubMed2001

Plasma adrenomedullin levels in patients on hemodialysis.

Adrenomedullin (AM) is a hypotensive peptide that has recently been isolated from human pheochromocytoma. In this study, we measured plasma AM concentrations in 54 patients on hemodialysis (HD) and examined the clinical significance. We also evaluated the effects of high-flux and low-flux dialysis membranes on plasma AM levels. The average value of plasma AM at pre-HD (4.44 +/- 0.16 fmol/ml) was significantly elevated compared with that in 44 healthy volunteers (1.31 +/- 1.41 fmol/ml) (p < 0.0001). The plasma AM concentrations at pre-HD showed a negative correlation with age and mean blood pressure (MBP) at pre-HD. The plasma AM concentrations at post-HD showed a negative correlation with MBP at post-HD and a negative correlation with the reduction rate of AM. Multiple regression analysis showed that age and MBP were independent factors associated with plasma AM at pre-HD and that MBP and reduction rate of AM were independent factors associated with plasma AM at post-HD. We investigated the differences between high-flux dialyzers (PS-UW, PS-N and FB-F) and a low-flux dialyzer (AM-BC-F), and we found that high-flux dialyzers removed plasma AM more efficiently than a low-flux dialyzer did. In addition, in 3 patients on HD, plasma AM levels decreased significantly during isovolumic dialysis using a high-flux dialyzer, despite the fact that there were no significant changes in MBP and ANP. In conclusion, elevation in plasma AM level causes a fall in MBP in patients on HD, therefore, removal of AM by HD treatment using a high-flux dialyzer contributes to the stability of blood pressure during HD.

Adrenomedullin↗
PubMed2001

Relationships of serum levels of insulinlike growth factors with indices of bone metabolism and nutritional conditions in hemodialysis patients.

Insulinlike growth factor (IGF) I and IGF-II are synthesized in osteoblasts and stimulate proliferation, differentiation, and matrix synthesis in these cells. There is some evidence that IGFs act on bone cells not only by paracrine but also by endocrine pathways, suggesting that circulating IGFs may be of importance for the regulation of bone metabolism. On the other hand, the serum IGF-I level is also thought to be a good indicator of the nutritional conditions in hemodialysis patients. The present study was performed to analyze the correlations of circulating levels of IGF-I, IGF-II, IGF-binding protein (IGFBP) 1 and IGFBP-3 with biochemical markers of bone metabolism and parameters of the urea kinetic model which reflect nutritional conditions in hemodialysis patients. We also examined the differences between these relationships in male and female patients on hemodialysis. Sixty-two hemodialysis patients, 36 men (male group) and 26 women (female group), were included in this study. We measured the serum levels of IGF-I, IGF-II, IGFBP-1, and IGFBP-3. The bone mineral content (BMC) of the radius was measured by dual-energy X-ray absorptiometry. We calculated Kt/V, protein catabolic rate, and percent creatinine generation rate (%CGR). We also examined the relationships between serum levels of IGFs and BMC and the parameters of the urea kinetic model. It was found that the serum levels of IGF-I in the hemodialysis patients were almost the same as those in the control group. However, the serum levels of IGF-II, IGFBP-1, and IGFBP-3 in the hemodialysis patients were significantly higher than those in the control group. In the male group, the serum IGF-I levels showed a significant correlation with both serum intact parathyroid hormone levels and BMC, but no significant correlations between these indices were found in the female group. The serum levels of both IGF-I and IGF-II showed significant correlations with %CGR in the male group, but not in the female group. Stepwise multiple regression analysis was performed to clarify the relationship between serum levels of IGFs and BMC or %CGR. It was found that age, hemodialysis duration, serum intact parathyroid hormone levels, and sex were independent factors associated with BMC. The %CGR was associated independently with serum levels of IGF-I, and IGF-II and with the presence of diabetes mellitus. In conclusion, it is thought that serum levels of IGF-I and IGF-II can be used as indices of nutritional conditions in hemodialysis patients. However, the serum IGF-I level cannot be used as a marker of bone metabolism in hemodialysis patients.

Biomarkers↗
PubMed2000

A brief course of colon preparation with oral antibiotics.

We carried out a prospective clinical trial of colon preparation with a regimen of oral antibiotics starting on the day before surgery. The patients were assigned to one of two groups consisting of either a mechanical preparation alone group (group 1, 45 cases) or a mechanical bowel preparation with oral antibiotics group (group 2, 38 cases). Group 2 received kanamycin and metronidazole three times on the day before surgery. Cefmetazole was administered for 3 consecutive days as prophylaxis in both groups. In a study using intraoperative mucosal swabs, the rates of group 2 patients with cultures yielding anaerobes or Gram-negative bacteria were significantly lower than those of group 1. There were no significant differences in the rates of patients with cultures yielding fungi or Gram-positive organisms. The positive culture rate in the peritoneal fluid of group 1 was also higher than that of group 2 (40%, 16%, P < 0.05). The surgical site infection rate was 18% in group 1 and 13% in group 2. Organisms isolated from the sites of postoperative infections were not identical with those from the peritoneal fluid. This relatively brief course preparation minimized the emergence of resistant strains. However, in spite of the colonic bacterial burden and the intraoperative inoculation in the patients with mechanical cleansing alone, their incidence of subsequent infections was comparable to that of patients who were administered oral antibiotics provided that the prophylactic antibiotic was administered for 3 days after surgery.

Administration, Oral↗
PubMed2000

Strictureplasty for short duodenal stenosis in Crohn's disease.

Involvement of the gastroduodenum is extremely rare in Crohn's disease. For obstructing duodenal Crohn's disease, bypass procedures have traditionally been selected. However, more recently, strictureplasty has become an acceptable surgical option. We treated two Crohn's disease patients with short proximal duodenal stenosis, using Finney-type strictureplasty. Their postoperative courses were uneventful and they have remained asymptomatic during follow-up periods of more than 5 years, and 4 months, respectively. Owing to the good clinical results of our two patients, we consider strictureplasty to be indicated for short proximal duodenal stenosis in Crohn's disease.

Adult↗