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H Funahashi

Publications and source records attributed to H Funahashi.

At least 55 records · Page 3Linked to original sources
PubMed2000

Zona reaction in porcine oocytes fertilized in vivo and in vitro as seen with scanning electron microscopy.

Morphological changes in zona pellucidae (ZP) isolated from in vitro-matured (IVM) and ovulated porcine oocytes were compared before or after fertilization in vitro and in vivo, respectively, by using scanning electron microscopy (SEM). The ZP of some ovulated or IVM oocytes and in vivo- or in vitro-fertilized (IVF) zygotes were equally split into two halves while immersed in an enzyme-inhibitor solution, using a surgical blade. After washing, intact and ZP halves were fixed in 1% glutaraldehyde solution in 0.1 M cacodylate buffer, processed, and examined using SEM. The outer surface of ZP in ovulated oocytes had a mesh-like structure. The outer morphology in IVM oocytes was more smooth although the mesh-like structure was still visible at high magnification. In in vivo zygotes and IVM-IVF zygotes, this lysed, mesh-like structure was more obvious. The inner surface of ZP had some small depressions (orifices). The mean number of orifices per 100 micrometer(2) of ZP surface was larger in IVM oocytes as compared to ovulated ones. The number of orifices per 100 micrometer(2) decreased in IVM-IVF zygotes as compared to IVM oocytes; whereas, in vivo zygotes did not differ from ovulated oocytes. The mean diameter of intact ZP as well as their mean thickness was greater in ovulated oocytes than IVM oocytes. The mean thickness of the ZP was larger in ovulated oocytes than IVM ones. The ZP thickness was larger in zygotes than in in vivo oocytes, whereas that of IVM-IVF zygotes did not differ from that of IVM oocytes. These results indicate that the morphology of ZP and the ZP reaction at sperm penetration appears to be much different between IVM oocytes and ovulated ones.

Animals↗
PubMed2000

Functional significance of colocalization of PACAP and catecholamine in nerve terminals.

Medullary neurons containing pituitary adenylate cyclase-activating polypeptide (PACAP) and noradrenalin (NA) project to the hypothalamus and they are involved in the regulation of arginine vasopressin (AVP) neurons. At the ultrastructural level, PACAP immunoreactivity was detected in the granular vesicles in catecholaminergic nerve terminals that made synaptic contact with AVP neurons. Both PACAP (at least 1 nM) and NA (at least 1 microM) induced large increases in the cytosolic Ca2+ concentration ([Ca2+]i) in isolated AVP cells. PACAP at 0.1 nM and NA at 0.1 microM had little effects, if any, on [Ca2+]i. However, when 0.1 nM PACAP and 0.1 microM NA were combined, they evoked large increase in [Ca2+]i in AVP neurons. An inhibitor of protein kinase A (PKA) completely inhibited the PACAP-induced increase in [Ca2+]i, but only partly inhibited the NA-induced increase in [Ca2+]i. In AVP cells that were prelabeled with quinacrine, PACAP and NA acted synergistically to induce a loss of quinacrine fluorescence, indicating secretion of neurosecretory granules in AVP neurons. The results suggest that PACAP and NA, coreleased from the same nerve terminals, act in synergy to evoke calcium signaling and secretion in AVP neurons, and that the synergism is mediated by the interaction between cAMP-PKA pathway an as yet unidentified factor "X" linked to L-type Ca2+ channels. The synergism between PACAP and NA may contribute to the regulation of AVP secretion under physiological conditions.

Animals↗
PubMed2000

Involvement of AP-1 and steroidogenic factor (SF)-1 in the cAMP-dependent induction of human adrenocorticotropic hormone receptor (ACTHR) promoter.

Adrenocorticotropic hormone receptor (ACTHR) is expressed predominantly in the adrenal glands, and its expression is upregulated by its own ligand, ACTH, via a cAMP-dependent pathway. In the present study, we characterized the 5'-regulatory region of human ACTHR gene to elucidate the molecular mechanisms underlying its adrenal-specific and ACTH/cAMP-dependent expression. The promoter region (-1017/+47 when the transcription start site is regarded as + 1) and its serial 5'-deletions (-764/+47, -503/+-47, -214/+47 and -56/+47) were ligated into the upstream of a luciferase (luc) reporter gene. These constructs were transfected into adrenocortical Y1 cells or non-adrenal JEG3 and Cos-1 cells. In all the cell lines, the luc activity gradually increased with serial 5'-deletions and the maximum activity was conferred by - 56/+ 47. However, the magnitude of luc activity of each deletion construct in non-adrenal cells was much less than that in Y1 cells, suggesting that the promoter functions in an adrenal-specific manner. We identified two Steroidogenic Factor (SF)-1-binding sites at -209 and -35. Electrophoretic mobility shift assay (EMSA) demonstrated that both sites bind to SF-1. Mutation of both sites significantly decreased the activity of -214/+47 promoter in Y1 cells. Transfection of SF-1-expressing plasmid into non-adrenal cells significantly increased the promoter activity, suggesting that SF-1 plays a role in the tissue-specific expression of human ACTHR gene. We identified the region, -764 to -503, that was required for the forskolin/cAMP responsiveness of the promoter. This region contains one AP-1 site. EMSA revealed that the binding of AP-1 to this site increased significantly upon treatment of Y1 cells with forskolin. Mutation of the site abolished the forskolin-responsiveness. In non-adrenal cells, the forskolin-responsiveness was observed only when SF-1-expressing plasmid was cotransfected. This is the first demonstration that both AP-1 and SF-1 are required for the cAMP-dependent induction of human ACTHR gene.

Animals↗
PubMed2000

[Chemopreventive effect of tamoxifen on familial breast cancer].

Chemopreventive effect of tamoxifen on familial breast cancer was studied. As it is impossible to use medicines for prevention of human breast cancer in Japan, a lot of investigations on animals using natural foods like as green tea, seaweed etc has been done. Seaweed wakame was effective on breast cancer proliferation in rat. In this paper 3 reports(Fisher, Powles and Veronesi) were reviewed and the results of some Japanese investigations in chemoprevention on animals were introduced. In Fisher's report tamoxifen was effective on breast cancer prevention, however in other 2 reports no effects were noticed because of the difference of risk. Study of Tamoxifen And Raloxifene(STAR) was started by NSABP in 1999.

Animals↗
PubMed2000

[An effective case of intraperitoneal and intra-arterial combined chemotherapy for unresectably advanced Borrmann type IV gastric carcinoma].

We report an effective case of intraperitoneal and intra-arterial combined chemotherapy for unresectably advanced Borrmann type IV gastric carcinoma. A 59-year-old man was admitted with advanced Borrmann type IV gastric carcinoma in June 1999. With informed consent, the patient underwent laparotomy, which revealed far advanced Stage IV gastric carcinoma of T4, N3, P1, H0, M1, CY1 for resection. Three ports to both subphrenic pouches and Douglas' pouch were placed for intraperitoneal infusion chemotherapy. Pathological findings of omental lesions were metastatic gastric carcinomas of por 2-histological type. Intraperitoneal and intravenous infusion combined chemotherapy with a modified low-dose CDDP and 5-FU regimen were started. The artery-side port was placed in the aorta at the Th. 9/10 levels for arterial infusion chemotherapy in September 1999. The patient was followed-up as an outpatient and continued to receive the intraperitoneal and intra-arterial combined chemotherapy. We report an effective case of intraperitoneal and intra-arterial combined chemotherapy for unresectably advanced Borrmann type IV gastric carcinoma, who could be followed-up as an outpatient while maintaining his quality of life.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

The effect of leptin on feeding-regulating neurons in the rat hypothalamus.

Intense immunoreactivity for the leptin receptor was detected in the hypothalamic arcuate nucleus (ARC), ventromedial nucleus (VMH), and lateral hypothalamus (LH) by immunohistochemistry. Cytosolic Ca2+ concentration ([Ca2+]i) in single neurons isolated from the ARC, VMH and LH was measured with dual wavelength fura-2 fluorescence imaging. A reduction of the superfusate glucose concentration from 10 to 1 mM increased [Ca2+]i in 21% of ARC neurons and 22% of LH neurons. Leptin at 0.1 nM inhibited the [Ca2+]i increase in 66 and 64% of these glucose-sensitive ARC and LH neurons, respectively. Inversely, 10 mM glucose increased [Ca2+]i in 49% of the VMH neurons, and 0.1 nM leptin at 1 mM glucose also increased [Ca2+]i in 84% of these glucose-responsive neurons. These results reveal that leptin inhibits the ARC and LH neurons and stimulates the VMH neurons via the leptin receptor expressed in these cells.

Animals↗
PubMed1999

Delayed neuronal cell death in the rat hippocampus is mediated by the mitogen-activated protein kinase signal transduction pathway.

Transient global ischemia caused by 5 min of cardiac arrest induced delayed neuronal cell death (apoptosis) in the CA1 region of the rat hippocampus. To characterize the molecular mechanisms that regulate apoptosis in vivo, the contributions to cell death of mitogen-activated protein kinase family members were examined in the hippocampal region after brain ischemia-reperfusion. Ischemia-reperfusion led to a strong activation of the JNK/SAPK (c-Jun NH2-terminal protein kinase/stress activated protein kinase), ERK (extracellular signal-regulated kinase), and p38 enzymes. These results with other previous studies suggest that the activation of JNK/SAPK in accordance with p38 contributes to the induction of apoptosis in CA1 neurons.

Animals↗
PubMed1999

Microwave Spectrum and Molecular Conformation of delta-Valerolactam.

Microwave rotational spectra for normal and N-deuterated species of delta-valerolactam (2-piperidinone) were observed in the frequency range from 8 to 40 GHz. The spectra of the ground vibrational states for two isotopic species and the excited vibrational states for normal species were assigned, and the rotational constants (MHz) in ground vibrational state were determined using the Watson A-reduced Hamiltonian: A = 4590.96(11), B = 2495.03(2), C = 1731.06(2) for normal species and A = 4436.79(13), B = 2484.49(1), C = 1703.83(1) for deuterated species, respectively. The comparison of the rotational constants and r(s) coordinates of the imino hydrogen atom with ones from the ab initio MO calculation at the MP2/6-31G(d, p) level of theory led to the conclusion that the spectra assigned were due to a half-chair conformer. One vibrationally excited state was observed and its vibrational frequency was 95(64) cm(-1). Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Successful surgical treatment of a solitary parapharyngeal metastasis from thyroid cancer, using the mandibular swing-transcervical approach: report of a case.

A 72-year-old man presented with a right parapharyngeal mass, 4 cm in diameter, which was subsequently diagnosed as a metastasis originating from papillary carcinoma of the thyroid gland. The parapharyngeal tumor was successfully removed by the mandibular swing-transcervical approach with pharyngeal reconstruction, performed using a buccal mucosal island flap based on the facial artery. His postoperative course was uneventful, and the preoperative clinical symptoms such as dysphagia and headaches completely resolved after surgery.

Aged↗
PubMed1999

Laparoscopic partial adrenalectomy.

BACKGROUND: Most laparoscopic adrenalectomies involve total removal of the whole adrenal gland, and reports of laparoscopic partial adrenalectomies have been very few. The criteria for performing a laparoscopic partial adrenalectomy have not been described. METHODS: (a) Patients with functioning adrenal tumors smaller than 3 cm in diameter were selected. (b) The solitary adrenal tumors were evaluated by preoperative thin-slice computed tomography (CT) scan. (c) Solitary lesions were reconfirmed with intraoperative ultrasonography. (d) Partial adrenalectomy was performed with at least a 5-mm margin using a vascular stapler. RESULTS: Laparoscopic partial adrenalectomy was performed in five patients using the vascular stapler. Hemostasis was perfect in all five patients. The tumor was located in the inferior part of the right adrenal gland in three cases and in the upper pole of the left adrenal gland in two cases. The postoperation pathologic diagnosis was adrenocortical adenoma in all five patients, and excessive hormonal levels or symptoms all disappeared. CONCLUSIONS: Laparoscopic partial adrenalectomy can be performed safely using a vascular stapler.

Adenoma↗
PubMed1999

A case-controlled study of laparoscopic compared with open lateral adrenalectomy.

BACKGROUND: Few studies have been done regarding laparoscopic transperitoneal lateral adrenalectomy compared with open transretroperitoneal lateral adrenalectomy in a case-controlled fashion. METHODS: A case-controlled study of 40 laparoscopic and 40 open adrenalectomies was done in patients who were matched for age, gender, endocrine disorder, side and size of tumor, and area of body surface. Follow-up was complete in 92.5% of the patients, with a mean follow-up period of 30 months. RESULTS: Statistically significant differences (P <0.05) were present (laparoscopic versus open) when the following results were compared: estimated blood loss (40 g versus 172 g), operating time (147 versus 79 minutes), analgesic equivalents (2.9 versus 5.2 times), hospital stay (12 versus 18 days), and late morbidity (0% versus 47.5%). There were no statistically significant differences between the laparoscopic and open groups with regard to time to oral intake, time to walking, intraoperative and early complications, and total cost. CONCLUSIONS: Laparoscopic adrenalectomy is a safe technique that results in greater patient comfort, decrease in estimated blood loss, and earlier discharge than open adrenalectomy, with no increase in cost. It should be adopted as the technique of choice for the removal of functioning adenomas and for adrenal masses less than 6 cm in diameter.

Adenoma↗
PubMed1999

Pituitary adenylate cyclase-activating polypeptide receptors during development: expression in the rat embryo at primitive streak stage.

The distribution and localization of the pituitary adenylate cyclase-activating polypeptide (PACAP) receptor the PAC1 receptor (previously called the type 1 PACAP receptor or PVR1), which binds PACAP, but not vasoactive intestinal peptide, with high affinity] were first investigated in rats with in situ hybridization for its messenger RNA, and with immunohistochemical methods during prenatal and postnatal development. The expression of PACAP receptor messenger RNA was first detected in the rat embryo at the primitive streak stage as early as embryonic day 9, and it was intensely expressed in the neural plate. PACAP receptor messenger RNA was also intensely expressed in the neuroepithelia of the mesencephalon and rhombencephalon at embryonic day 11, and expressed in the basal telencephalon, hippocampal formation neuroepithelium, cortical neuroepithelium and cerebellar neuroepithelium after embryonic day 13. It was also expressed in the olfactory bulb neuroepithelium after embryonic day 16, and in mature regions of the older embryos. In postnatal developing brains, PACAP receptor messenger RNA was intensely expressed in the olfactory bulb, hippocampal formation, cerebellum and other scattered regions. The localization of PACAP receptor-like immunoreactivity coincided well with that of the gene transcripts. We also used reverse transcription-polymerase chain reaction methods to determine the expression of the splice variants of the PACAP receptor gene. At each ontogenetic stage of the rat from embryonic day 9 to postnatal day 60, two major products were detected with reverse transcription-polymerase chain reaction, a thick band (303 base pairs) corresponding to the short splice variant of the receptor that lacks both the "hip" and "hop" cassettes, and a thin band (387 base pairs) corresponding to the splice variant that contains one cassette of "hop" or "hip". There was no evidence for the other larger splice variants. Some of the amplified products were sequenced and found to have the exact sequences of "PACAP receptor" and "PACAP receptor-hopl", which are coupled to different signal transduction pathways. These results indicate that the PACAP receptor is actively expressed in different neuroepithelia from early developmental stages and expressed in various brain regions during prenatal and postnatal development, and that the major splice variants are "PACAP receptor" and "PACAP receptor-hopl". The initial mapping of ontogenetic localization of the PACAP receptor provides the basis for a better understanding of the functions of PACAP and its receptors during the development of the brain.

Animals↗
PubMed1999

Effect of glycine on 5-aminolevulinic acid biosynthesis in heterotrophic culture of Chlorella regularis YA-603.

Chlorella regularis strain YA-603 was previously found to exhibit a comparatively high growth rate and improved 5-aminolevulinic acid (ALA) productivity when cultured heterotrophically. Although the universal tetrapyrrole precursor ALA is synthesized from glutamate in algae and higher plants, in this study the addition of glutamate to the medium did not enhance ALA production in the heterotrophic culture of C. regularis YA-603. On the other hand, the addition of glycine, which is a precursor of ALA biosynthesis via the Shemin pathway in animal cells and some bacteria, enhanced both the specific growth rate and ALA production. Moreover, when a second glycine addition was made during the culture, the ALA concentration increased by about 1.5 times compared to that obtained with one glycine addition. From these results, it is suggested that the Shemin pathway contributes to ALA production, and that addition of glycine in the heterotrophic culture of C. regularis YA-603 can significantly increase the amount of ALA produced.

Journal Article↗
PubMed1999

DNA stability and thiol-disulphide status of rat sperm nuclei during epididymal maturation and penetration of oocytes.

DNA stability and thiol-disulphide status of rat sperm nuclei was observed in vivo during maturation in the epididymis and penetration of oocytes. When spermatids and spermatozoa were stained with acridine orange after fixation with acetic alcohol, the red/green fluorescence ratio observed under a confocal microscope was not different between spermatids (3.81 +/- 0.16) and testicular spermatozoa (4.03 +/- 0.34), and then decreased sharply (p < 0.01) as the spermatozoa descended the epidymis to the caput epididymis (1.13 +/- 0.03). However, the ratio was not different among corpus (0.69 +/- 0.01), cauda epididymis (0.68 +/- 0.11) and ejaculated spermatozoa (0.63 +/- 0.01). On the other hand, when spermatozoa were labelled with monobromobimane (mBBr), the fluorescence intensities gradually decreased (p < 0.01) during passage of spermatozoa from testis (4.74 +/- 0.16) through epididymis (caput, 2.72 +/- 0.08; corpus, 1.07 +/- 0.03; cauda, -0.05 +/- 0.05; ejaculated, 0.08 +/- 0.03). The acridine orange red/green fluorescence ratio increased (p < 0.01) during zona penetration (binding sperm, 0.52 +/- 0.09; perivitelline sperm, 0.64 +/- 0.16) and sperm decondensation (decondensed sperm, 0.69 +/- 0.12). When spermatozoa in the perivitelline space were labelled with mBBr, the fluorescence was detected. These results demonstrate that DNA stability against acid appears to be ahead of the oxidation of protamine during sperm maturation in the epididymis and is an initial event of the unpackaging process in rat genome occurring during or just after zona penetration but before ooplasm penetration.

Acridine Orange↗
PubMed1999

Changes in intracellular content of glutathione and thiols associated with gamma-glutamyl cycle during sperm penetration and pronuclear formation in rat oocytes.

The content of glutathione and other thiols in rat eggs was examined during sperm penetration and pronuclear formation by high-performance liquid chromatography with fluorescence detection. Reduced glutathione (GSH) content was higher in unfertilized oocytes (8.50 +/- 0.29 pmol/egg) and penetrated eggs with a decondensed sperm nucleus (DSH eggs; 7.72 +/- 0.56 pmol/egg) than eggs at the pronuclear stage (PN eggs; 5.93 +/- 0.10 pmol/egg). The content of oxidised glutathione (GSSG) was not different among experimental groups (152.6 +/- 74.1 nmol/egg in unfertilized eggs, 146.0 +/- 50.0 nmol/egg in DSH eggs and 39.7 +/- 17.3 nmol/egg in PN eggs). The GSSG/GSH ratio did not change during fertilization. Although the reduced cysteinylglycine content of eggs did not change among experimental groups, the oxidised form of cysteinylglycine increased (p < 0.025) between sperm decondensation (6.9 +/- 1.5 nmol/egg in unfertilized oocytes and 10.1 +/- 2.1 nmol/egg in DSH eggs) and pronuclear formation (40.5 +/- 11.5 nmol/egg in PN eggs). Low contents of cystine were detected during fertilization but cysteine and gamma-glutamylcysteine were not detected in any treatment groups. These results demonstrate that GSH content in rat eggs decreases between sperm decondensation and pronuclear formation, probably due to the increased activity of gamma-glutamyl transpeptidase.

Animals↗
PubMed1999

Production of plasminogen activators (PAs) in bovine cumulus-oocyte complexes during maturation in vitro: effects of epidermal growth factor on production of PAs in oocytes and cumulus cells.

We examined whether plasminogen activators (PAs) are produced by bovine cumulus-oocyte complexes (COCs) during maturation in vitro. The effects of epidermal growth factor (EGF) on production of PAs in oocytes and cumulus cells were also examined. When COCs were cultured for 24 h with 30 ng/ml EGF, three plasminogen-dependent lytic zones (58.5 +/- 3.5 kDa, 79.0 +/- 3.0 kDa, and 113.5 +/- 6.5 kDa) were observed. Addition of amiloride, a competitive inhibitor of urokinase-type PA (uPA), to the zymogram eliminated the activity of the 58.5 +/- 3.5-kDa zone, suggesting that this band is a uPA. However, since the activity of the remaining two bands was not eliminated, it was suggested that the 79.0 +/- 3.0-kDa band is a tissue-type PA (tPA) and the 113.5 +/- 6.5-kDa band is possibly a tPA-PA inhibitor (tPA-PAI) complex. In COCs before culture, however, no activity of PAs was detected. At 6 h of culture, the same level of uPA activity was detected in COCs cultured both in the absence and in the presence of EGF. The uPA activity was increased at 12 h of culture but without further increase at 24 h of culture, with higher activity in the presence than in the absence of EGF. The activity of tPA and tPA-PAI was first detected at 24 h of culture in the absence of EGF. In the presence of EGF, however, some activity of tPA-PAI was detected at 12 h of culture. At 24 h of culture, the activity of all PAs was detected in cumulus cells, but only uPA activity was detected in oocytes, with higher activity in the presence than in the absence of EGF. The uPA activity in oocytes was not detected when they were cultured without cumulus cells in either the presence or absence of EGF, although cumulus expansion was stimulated by EGF, exhibiting a time-course similar to that observed in PA production. These results suggest that uPA, tPA, and tPA-PAI are all produced by bovine COCs, but only uPA by oocytes, during maturation in vitro. However, cumulus cells play an essential role or roles in the production of uPA by oocytes, and EGF enhances the roles of cumulus cells.

Amiloride↗