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Biomedical subjects

M Seki

Publications and source records attributed to M Seki.

At least 199 records · Page 11Linked to original sources

Factors affecting the development of oocytes and embryos in IVF-ET.

In our study in hMG/hCG protocol, there is correlation between basal FSH level and number of oocyte retrieved (Rs = -0.4334, p = 0.039). FSH was not useful in predicting poor responders in an in vitro fertilization program where pituitary desensitization is routinely used. There is correlation between day 2, day 3 serum immunoactive inhibin level and number of follicle developed with hMG alone, or with hMG in conjunction with pituitary desensitization using a buserelin intranasal spray. The patients were divided by relationship between E2 peak and inhibin peak. The most of oocytes retrieved, oocytes fertilized and embryos cleaved were obtained when hCG was injected on the E2 peak day following the inhibin peak day. Inhibin concentration in aspirated follicular fluids was low and estradiol concentration was high in pregnant group. There is correlation between acceleration index of inhibin and number of oocyte retrieved in both protocols. Inhibin levels were significantly lower (P < 0.05) in women older than 36 years of age, although estradiol responses were not so influenced by age. These data suggest that: (1) In the early follicular phase, inhibin may be a valid index to predict ensuing follicular growth and follicular development. (2) The serum inhibin responses to maximal ovarian stimulation may be a sensitive and early index of declining ovarian function with advancing age. (3) Inhibin is an important factor for the diagnosis of pregnancy outcome.

Adult↗

Advantages of using the midline incision right retroperitoneal approach for abdominal aortic aneurysm repair.

This study was conducted to compare the midline incision right retroperitoneal approach for repairing abdominal aortic aneurysms (AAA) with the transperitoneal approach. The intra- and postoperative course of 15 patients who underwent AAA repair using the transperitoneal approach between 1987 and 1991 and another 15 patients who underwent AAA repair using the retroperitoneal approach between 1991 and 1994 were evaluated. The incidence of postoperative wound complications was also assessed. There was no operative or hospital death in either group. Although a significantly longer interval was required from the incision to the aortic clamp using the extraperitoneal method, there were no statistical differences in the aortic clamping time, total operation time, or blood loss between the two groups. On the other hand, there was a statistically significant improvement in bowel function and a significant reduction in the length of postoperative hospitalization following the extraperitoneal procedure. Furthermore, no wound complications such as those associated with the left flank incision developed after the extraperitoneal procedure. Thus, we recommend the midline incision right retroperitoneal approach for AAA as it does not involve muscle division and is associated with fewer complications.

Aged↗

Successful salvage of aortoesophageal fistula caused by a fish bone.

We report saving the life of a 66-year-old woman with an aortoesophageal fistula caused by a fish bone. In this case, a hemostastic clip, which was applied to the lesion during emergency endoscopy, facilitated the subsequent diagnosis of this fistula by diagnostic imaging. Compressive hemostasis was effective in controlling preoperative bleeding.

Aged↗

Effects of recombinant human granulocyte colony-stimulating factor on the growth potential of two murine myeloid leukemias.

We investigated the in vitro and in vivo effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on the proliferation of two murine leukemic cell lines. The rhG-CSF stimulated leukemic colony formation of the promyelocytic leukemic cell line L-8801 in methylcellulose culture and increased the number of L-8801 cells in liquid culture. However, rhG-CSF treatment prolonged the median survival period of mice implanted with L-8801 cells and the emergence of the leukemic blast cells in peripheral blood. Meanwhile, rhG-CSF had no influence on that of the megakaryoblastic leukemic cells L-8057 and failed to prolong the median survival period of L-8057 leukemic mice. Receptor binding analysis revealed that L-8801 cells expressed a G-CSF receptor (Kd=125 pM, 479 binding sites/cell) and L-8057 cells had no G-CSF receptors. Then, we examined the growth potential of these cells. The median survival period was longer for mice implanted with L-8801 cells cultured with rhG-CSF for 72 h in vitro than for cells grown without rhG-CSF. Furthermore, the median survival period of mice implanted with spleen cells from L-8801 leukemic mice treated with rhG-CSF was prolonged compared with those from leukemic mice without rhG-CSF. In contrast, there was no effect of rhG-CSF on the growth potential of the spleen from L-8057 leukemic mice. The results of our present study demonstrate that rhG-CSF reduced the growth of L-8801 leukemic cells in vitro and in vivo mediated through G-CSF receptors, thereby suppressing the development of leukemia.

Animals↗

Functional assessment of patients with spinal cord injury: measured by the motor score and the Functional Independence Measure.

There is some information about the Functional Independence Measure (FIM) score of patients with spinal cord injury (SCI), but there are a few publications dealing with the relationship between the FIM score and the motor score of the American Spinal Injury Association (ASIA). We have studied the relationship of all FIM items with the motor score, and reviewed the disability of patients with spinal cord injury in greater detail. The purpose of this study was to describe the characteristics of impairment and disability in patients with SCI, using the FIM and motor score of the ASIA. The subjects were 100 inpatients with SCI (Frankel A, B). Neurological level, days from the onset, and the FIM were examined. In addition to these items, the ASIA motor scores were calculated for 22 tetraplegic patients. We investigated the relationships among these various respects. We also examined the changes of the physical items of the FIM score (physical FIM) over time for 18 patients. The mean FIM scores of those with tetraplegia with C4, C5, C6, C7, C8 lesions, and those with paraplegia with above T5 levels, and those below T6 were 35, 61, 82, 90, 116, 114 and 114 respectively. The FIM score reached the plateau in approximately 10 months, 6 months and 3 months post-injury, in tetraplegia, paraplegia above T5 and that below T6 respectively. The FIM scores in C6 patients were widely distributed from 56 to 104. On the other hand, the ASIA motor score could subdivide C6 patients and related well to the FIM score. The mean FIM scores for each neurological level were similar to those previously reported, thus they appeared to be plateau scores. With regard to the motor score, we feel that it could reflect the disability of the patients better than considering the neurological levels alone. Also considering the changes in the physical FIM score over time within a year from the onset of the injury, there were differences in the ADL improvement patterns among patients with different neurological levels. It appears that timing of the highest physical FIM improvement for each neurological level can exist. Thus it is important not to delay the start of the rehabilitation of patients with spinal cord injury in proper time.

Activities of Daily Living↗

Characterization of the properties of a human homologue of Escherichia coli RecQ from xeroderma pigmentosum group C and from HeLa cells.

We showed that DNA-dependent ATPase Q1 (DNA helicase Q1) from xeroderma pigmentosum complementation group C (XP-C) cells elutes from FPLC Mono Q column at higher concentrations of KCl than that from other human cells (35). We purified DNA helicase Q1 from XP-C and HeLa cells. The purified fractions of both cells contained a major polypeptide with a molecular mass of 73 kDa and had the same enzymatic properties, including salt- and temperature-sensitivity. Characterization using an anti-DNA helicase Q1 antibody indicated that this enzyme localized in the nuclei and was not modified by incorporating phosphate groups through phosphorylation and ADP-ribosylation. No interactions of DNA helicase Q1 with other proteins were indicated by immunoprecipitation of the helicase from crude extracts. No difference was observed in XP-C cells in intracellular localization of DNA helicase Q1, phosphorylation, and the interaction with other proteins as compared to HeLa cells.

Adenosine Triphosphatases↗

[Reconstruction of chest wall defects with autogenous ribs grafts].

Three methods of chest wall reconstruction using autogenous rib grafts were reported. Fresh non-vascularized autogenous rib graft, vascularized autogenous ribs with muscle-flap, and pasteurized autogenous rib grafts were the materials used in these techniques. They are less convenient than those with artificial materials but afterwards physiologically more natural chest wall will be reconstructed. The third method (pasteurized rib graft) was applied to 22-year-old female with large recurrent desmoid tumor. Six resected ribs were heated in the saline at 60 degrees C for 30 min. and three of them were returned to the former position. Though tumor cells and bacteria are killed under this condition, these heated bone can be revascularized and replaced by normal bone as early as fresh non-vascularized rib graft.

Adult↗

The usefulness of ultrasonic microprobe imaging for endoscopic variceal ligation.

OBJECTIVES: This study investigated whether ultrasonic microprobe (UMP) imaging was useful in judging the therapeutic effect of endoscopic variceal (EVL) on varices as well as assessing varices and surrounding vessels before and after EVL. METHODS: UMP imaging was performed repeatedly safely and easily via the biopsy channel of an endoscope in 20 patients with esophageal varices. Using this modality in combination with our method of "intensive ligation," we treated esophageal varices successfully. RESULTS: Before EVL, UMP imaging displayed esophageal varices, periesophageal collaterals, and the azygous vein as echo-free lumens. In 15 of 20 patients, UMP imaging clearly detected the perforating vein, one of the optimal ligation sites for EVL, connecting the varix and collateral vein. Just after EVL, UMP imaging revealed a hyperechoic change ("snow ball" sign or "snow channel" sign), indicating blood flow stasis in the esophageal varices. On subsequent EVL, UMP imaging showed the cross-sectional area of varices was undetectable (occluded) or partially detectaable. After repeated EVL (2.9 treatment sessions on average), UMP imaging, as well as endoscopy, indicated that almost all varices were eradicated (undetectable). However, UMP imaging demonstrated that neither collaterals nor the azygous vein had significantly changed in size. CONCLUSIONS: This modern diagnostic modality provided a clinical adjunct to current endoscopy when observing esophageal varices and surrounding vessels before and after EVL to determine the need for additional therapy.

Aged↗

Stimulation of DNA synthesis by mouse DNA helicase B in a DNA replication system containing eukaryotic replication origins.

A number of DNA helicases have been isolated from mammalian cells, but their abilities to stimulate DNA replication accompanied with DNA unwinding have not been addressed so far. We constructed a model DNA replication system using the yeast autonomously replicating sequence (ARS) as the replication origin. In this system, SV40 T antigen as a DNA helicase assembles to the replication origin where the DNA duplex is unwound by torsional stress due to the negative supercoiling of template DNA, which leads to bidirectional DNA replication from the origin. We report here that DNA helicase B isolated from mouse FM3A cells can greatly stimulate DNA synthesis in this replication system in place of SV40 T antigen. DNA synthesis was dependent on the presence of single-stranded DNA binding protein (RP-A), DNA polymerase alpha/primase from mouse cells, and Escherichia coli DNA gyrase. DNA gyrase was required not only at elongation as a DNA swivelase but also at initiation to increase negative superhelical density of template DNA with the assistance of RP-A. A mammalian DNA fragment containing a replication initiation zone upstream of the c-myc gene as well as the yeast ARS fragment acted as a cis-element in this system using DNA helicase B. Both DNA helicase B and SV40 T antigen have the ability to extensively unwind the template DNA in the presence of RP-A and DNA gyrase, which may be crucial for stimulation of DNA synthesis in this system.

Adenosine Triphosphatases↗

Effective production of the hepatitis C virus core antigen having high purity in Escherichia coli.

The amino-terminal half of putative nucleocapsid (core) protein (amino acids 1-115) of hepatitis C virus (HCV) was directly overproduced in Escherichia coli under the control of the tac promoter. Overproduction of core antigen was achieved by inserting several target genes and by optimizing the culture conditions, whereas a large amount of directly expressed and purified core antigen has not yet been reported. Although the level of expression was comparable to that of the conventional E. coli fused expression system, our recombinant proteins contain only HCV amino acid sequence. Using recombinant E. coli, overproduced large-scale culture system was achieved in jar-fermenter. A highly purified sample of the expressed protein was obtained by ion-exchange and gel permeation column chromatography in the presence of 8 M urea. From a 3.5 l culture, approximately 440 mg of recombinant core protein was obtained after a two-step purification procedure. An enzyme-linked immunosorbent assay developed using the highly purified antigen satisfactorily diagnosed hepatitis C.

Base Sequence↗

Successful expression in pollen of various plant species of in vitro synthesized mRNA introduced by particle bombardment.

Gold particles coated with beta-glucuronidase (GUS) mRNA with a 5' cap structure that had been synthesized in vitro were introduced, by use of a pneumatic particle gun, into pollen grains of lily (Lilium longiflorum), freesia (Freesia refracta) and tulip (Tulipa gesneriana). A fluorometric assay for the GUS activity indicated that in vitro synthesized GUS mRNA introduced into these pollen cells by particle bombardment was successfully expressed. GUS activity in extracts of the bombarded lily pollen became detectable fluorometrically within 30 min after bombardment, peaked at 6 h, then gradually decreased. This activity changed as a function of the developmental stage of the pollen cell of lily.

Gene Expression↗

Improvement of anemia in W/WV mice by recombinant human erythropoietin (rHuEPO) mediated through EPO receptors with lowered affinity.

We studied the effects of recombinant human erythropoietin (rHuEPO) on anemic W/WV mice which manifested severe anemia accompanied by mutation of the W gene encoding tyrosine kinase type receptor (c-kit gene) of bone marrow hematopoietic cells. Nine-week-old male W/WV mice or normal littermates (+/+) were used. Since serum EPO concentration in W/WV mice increased in proportion to severity of anemia, EPO production in the kidneys of these animals was found to be regulated normally. Hematocrit in +/+ mice increased and a maximal response was also obtained with 2,000 IU/kg of rHuEPO. On the other hand, hematocrit in W/WV mice increased in a dose-responsive manner by administration with 2,000 and 10,000 IU/kg, showing different responses to rHuEPO in these two types of mice. The responsiveness of W/WV mice to rHuEPO was low in terms of increases in erythroblastic precursor cells (CFU-E), and immature cells in the bone marrow. Scatchard analysis of the specific binding of 125I-rHuEPO against bone marrow cells revealed that the different responsiveness to rHuEPO between W/WV and +/+ mice may be correlated with differences in affinity of EPO receptor of bone marrow cells in these mice. From these results, a high dose of rHuEPO is capable of improving the anemia in W/WV mice that had EPO receptors with lowered affinity, indicating the possible effectiveness of rHuEPO in anemic patients with EPO receptor abnormality.

Anemia↗

Efficient replication of polyomavirus DNA in a cell-free system supplemented with Escherichia coli single-stranded DNA binding protein, which exhibits species-specificity in the requirement for DNA polymerase alpha-primase.

We established a modified cell-free system for polyomavirus (PyV) DNA replication, which was supplemented with Escherichia coli single-stranded DNA binding protein (SSB). DNA synthesis in this system was enhanced by 1.4- to over 15-fold depending upon the amount of cell extracts contained in the reaction mixture. By supplementing with E. coli SSB, we were able to reduce the amount of cell extracts in the reaction mixture, and to lower the concentrations of creatine phosphate and Tris, rendering this system more resistant to salts than the conventional PyV DNA replication system. The modified system was characterized using mutant cell extracts which had heat-inactivated DNA polymerase alpha. DNA synthesis in the system was dependent on PyV T antigen, the PyV origin of DNA replication, mutant cell extracts, and DNA polymerase alpha-primase complex purified from wild-type cells. The DNA polymerase alpha-primase complex was not replaced by DNA polymerase alpha, indicating that this system requires a functional DNA polymerase alpha-primase complex. This system exhibited species-specificity in the requirement for DNA polymerase alpha-primase; only mouse DNA polymerase alpha-primase but not human DNA polymerase alpha-primase functioned in this system.

Animals↗

Phosphorothioate antisense oligodeoxynucleotides capable of inhibiting hepatitis C virus gene expression: in vitro translation assay.

Phosphorothioate antisense oligodeoxynucleotides (S-ODNs) designed to hybridize to the 5' region of the hepatitis C virus (HCV) genome were evaluated as to their ability to inhibit HCV gene expression, using an in vitro translation system. Three effective regions were found to interfere with the translation of HCV RNAs. These regions were region A [nucleotides (nt) 124 to 153], region B (nt 100 to 123), and region C (nt 324 to 360). Further detailed evaluation of S-ODNs within each region allowed us to propose some HCV-specific antiviral agent candidates. Two of them, SMS16 (nt 328 to 347) and SMS17 (nt 326 to 345), caused over 90% inhibition of HCV gene expression when present in a less than fourfold molar excess; this effect was sequence-specific and dose-dependent.

Antiviral Agents↗

Utility of Tc-99m GSA SPECT imaging in estimation of functional volume of liver segments in health and liver diseases.

The authors examined whether there was a difference in liver function among hepatic segments in liver cirrhosis cases, and in cases of hepatocellular carcinoma (HCC) associated with liver cirrhosis. If the average counts in the lateral segment of the left lobe were set at 1, the average counts in the right upper and lower segment of the liver were 0.75 approximately 1.02 (0.89 +/- 0.09, mean +/- SD) in normal cases, 0.38 approximately 2.24 (1.01 +/- 0.39) in liver cirrhosis cases, and 0.61 approximately 2.85 (1.15 +/- 0.58) in HCC cases. There is a significant difference between normal cases and liver cirrhosis cases or HCC cases (P < 0.001). Also, in HCC cases, if the average counts in the cancer-bearing segment of the liver were set at 1, the average counts in the noncancerous segment of the liver were 0.55 approximately 2.85 (1.23 +/- 0.58), and many average counts in the cancer-bearing segment were equal to, or lower than those in the noncancerous segment. It has been found that there were significant differences in function among hepatic segments in liver cirrhosis cases, and in HCC cases. Furthermore, the liver function in the cancer-bearing segment tended to be worse due to the existence of carcinoma compared with that in the noncancerous segment.

Adult↗