Biomedical subjects

T Moriguchi

Publications and source records attributed to T Moriguchi.

At least 73 records · Page 4Linked to original sources

PubMed1999

[Supramicrosurgical lymphaticovenular anastomosis for the treatment of lymphedema in the extremities].

During the past eight years, we treated obstructive lymphedema of a unilateral upper extremity in 27 females and of a unilateral or bilateral lower extremity in 35 males and females with supramicrosurgical lymphaticovenular anastomoses and/or conservative treatment. The most common cause of upper limb edema was mastectomy with or without subsequent radiation therapy for breast cancer, and that of lower limb edema was hysterectomy with radiation. As an objective assessment of edema, the circumferences of the affected and opposite normal forearms or lower legs were measured 10 cm below the olecranon of the arm or the lower border of the patella. In patients who received conservative treatment (12 arms and 12 legs), the average excess circumferential length of the affected arm and leg was 6.4 and 7.1 cm over that of normal extremities, average duration of edema before treatment was 3.5 and 5.2 years, average period for conservative treatment was 10.6 months and 1.5 years, and average decreased circumferential length was 0.8 and 0.6 cm, respectively. The rate of circumferential decrease over 4 cm was none in arm and 16.7% in leg edema. In patients who underwent surgery (12 arms and 16 legs), the average excess circumferencial length was 8.9 and 9.8 cm, average duration of edema before surgery was 8.2 and 8.9 years, average follow-up after surgery was 2.2 and 3.3 years, and average decrease in excess circumference was 4.1 and 2.7 cm, respectively. The rate of circumferential decrease over 4 cm was 58.3% in arms and 50% in legs. These results indicate that supramicrolymphaticovenular anastomoses have a valuable place in the treatment of obstructive lymphedema.

Adult↗

PubMed1998

Characterization of a cDNA homologous to carotenoid-associated protein in citrus fruits.

A cDNA (CitPAP) homologous to a gene encoding for Cucumis sativus carotenoid-associated protein (CHRC) has been isolated from satsuma mandarin (Citrus unshiu Marc.). Unlike ChrC whose expression was limited only in mature fruits (containing chromoplasts), CitPAP transcripts were detected in all the tissues examined including fruits, flowers and leaves. In this respect, CitPAP was rather close to a gene encoding for pepper plastid-lipid-associated protein (PAP), which exhibits ubiquitous expression in bell pepper organs containing chloroplasts or chromoplasts. CitPAP, however, differed from PAP in the magnitude and pattern of RNA accumulation. These results might indicate a novel function of CitPAP.

Amino Acid Sequence↗

PubMed1998

T lymphocyte activation signals for interleukin-2 production involve activation of MKK6-p38 and MKK7-SAPK/JNK signaling pathways sensitive to cyclosporin A.

p38/CSBP, a subgroup member of mitogen-activated protein kinase (MAPK) superfamily molecules, is known to be activated by proinflammatory cytokines and environmental stresses. We report here that p38 is specifically activated by signals that lead to interleukin-2 (IL-2) production in T lymphocytes. A p38 activator MKK6 was also markedly activated by the same stimulation. Pretreatment of cells with SB203580, a specific inhibitor of p38, as well as expression of a dominant-negative mutant of MKK6, suppressed the transcriptional activation of the IL-2 promoter. We also demonstrated that MKK7, a recently described MAPK kinase family member, plays a major role in the activation of stress-activated protein kinase (SAPK)/c-Jun NH2-terminal kinase (JNK) in T lymphocytes. Moreover, a dominant-negative mutant of MKK7 abrogated the transcriptional activation of the distal nuclear factor of activated T cells response element in the IL-2 promoter. Cyclosporin A, a potent immunosuppressant, inhibited activation of both p38 and SAPK/JNK pathways but not the MAPK/extracellular signal-regulated kinase (ERK) pathway. Our results indicate that both MKK6 to p38 and MKK7 to SAPK/JNK signaling pathways are activated in a cyclosporin A-sensitive manner and contribute to IL-2 gene expression in T lymphocytes.

Calcium-Calmodulin-Dependent Protein Kinases↗

PubMed1998

Nuclear export of cyclin B1 and its possible role in the DNA damage-induced G2 checkpoint.

M-phase-promoting factor (MPF), a complex of cdc2 and a B-type cyclin, is a key regulator of the G2/M cell cycle transition. Cyclin B1 accumulates in the cytoplasm through S and G2 phases and translocates to the nucleus during prophase. We show here that cytoplasmic localization of cyclin B1 during interphase is directed by its nuclear export signal (NES)-dependent transport mechanism. Treatment of HeLa cells with leptomycin B (LMB), a specific inhibitor of the NES-dependent transport, resulted in nuclear accumulation of cyclin B1 in G2 phase. Disruption of an NES which has been identified in cyclin B1 here abolished the nuclear export of this protein, and consequently the NES-disrupted cyclin B1 when expressed in cells accumulated in the nucleus. Moreover, we show that expression of the NES-disrupted cyclin B1 or LMB treatment of the cells is able to override the DNA damage-induced G2 checkpoint when combined with caffeine treatment. These results suggest a role of nuclear exclusion of cyclin B1 in the DNA damage-induced G2 checkpoint.

Animals↗

PubMed1998

Characterization of gene repertoires at mature stage of citrus fruits through random sequencing and analysis of redundant metallothionein-like genes expressed during fruit development.

We carried out a random sequencing of cDNA library derived from mature citrus fruit (Citrus unshiu Marc.) for identifying the gene repertoires expressed at the mature stage. Among 297 clones analyzed, 195 cDNA clones (65.7%) were putatively identified to previously characterized genes with optimized (OPT) scores of >/=200 through a homology search to DNA database, whereas 102 clones (34.3%) resulted in low OPT scores (<200) and did not show any significant sequence identity with previously published genes. Among them, clones homologous to metallothionein (MT)-like genes appeared 62 times, being mostly redundant, and accounting for about 20.9% of the total 297 clones. To gain a better understanding of the MT-like genes, two types of cDNA clones were isolated. One clone (CitMT36) resembled the type 2 MT gene containing Cys-X-Cys motifs in both N- and C-terminal, but the consensus sequence in the N-terminal domain, Cys-Cys and Cys-X-X-Cys was modified in CitMT36 to X-Cys and Cys-X-X-X, respectively. We suggest that these form a 'novel type 2' group of MT-like clones. The other clone (CitMT45) showed homology to type 3 MT-like genes, which have been found in mostly fruit tissues so far. By Southern blot analysis, both clones showed one or two bands, suggesting that both CitMT36 and CitMT45 are present in single or a few copies in the citrus genome. Transcripts of CitMT36 were evenly detected in all tissues examined, whereas those of CitMT45 were detected primarily in fruit during the developmental phase. Neither of the MT-like genes was induced in leaves by Zn and Cu. Collectively, MT-like genes from citrus would be regulated differentially depending on the fruit developmental stage and organs, indicating a change in their expression under the different physiological and molecular environment of fruit cells.

Amino Acid Sequence↗

PubMed1998

Activation of the protein kinase p38 in the spindle assembly checkpoint and mitotic arrest.

The mitogen-activated protein kinase (MAPK) superfamily comprises classical MAPK (also called ERK), c-Jun amino-terminal or stress-activated protein kinase (JNK or SAPK), and p38. Although MAPK is essential for meiotic processes in Xenopus oocytes and the spindle assembly checkpoint in Xenopus egg extracts, the role of members of the MAPK superfamily in M phase or the spindle assembly checkpoint during somatic cell cycles has not been elucidated. The kinase p38, but not MAPK or JNK, was activated in mammalian cultured cells when the cells were arrested in M phase by disruption of the spindle with nocodazole. Addition of activated recombinant p38 to Xenopus cell-free extracts caused arrest of the extracts in M phase, and injection of activated p38 into cleaving embryos induced mitotic arrest. Treatment of NIH 3T3 cells with a specific inhibitor of p38 suppressed activation of the checkpoint by nocodazole. Thus, p38 functions as a component of the spindle assembly checkpoint in somatic cell cycles.

3T3 Cells↗

PubMed1998

Differential activation of two JNK activators, MKK7 and SEK1, by MKN28-derived nonreceptor serine/threonine kinase/mixed lineage kinase 2.

MKN28-derived nonreceptor type of serine/threonine kinase/mixed lineage kinase 2 (MST/MLK2) directly phosphorylates and activates SEK1/MKK4/JNKK1/SKK1 in vitro, thereby acting as a mitogen-activated protein (MAP) kinase kinase kinase in the JNK/SAPK pathway (Hirai, S. -i., Katoh, M., Terada, M., Kyriakis, J. M., Zon, L. I., Rana, A., Avruch, J., and Ohno, S. (1997) J. Biol. Chem. 272, 15167-15173). The in vitro reconstitution system for the kinase cascade allowed us now to identify JNK/SAPK activators involved in the MST/MLK2-dependent activation of JNK/SAPK in vivo. We show that at least two distinct MST/MLK2-dependent JNK/SAPK activators are present in the fractionated COS-1 cell lysate, and that they appear to be SEK1/MKK4/JNKK1/SKK1 and MKK7/JNKK2/SKK4 by Western blot analysis. Notably, a majority of the MST/MLK2-dependent JNK/SAPK-activating activity is found in MKK7-containing fractions, whereas the MEKK1-dependent activity is comparably distributed in SEK1- and MKK7-containing fractions. Moreover, MST/MLK2 activates recombinant MKK7 more effectively than recombinant SEK1, whereas MEKK1 activates both to a similar extent. In addition, the deletion analysis on MST/MLK2 showed that the kinase domain is responsible for the determination of substrate specificity. These results provide a molecular aspect to the differential regulation of the two JNK activators by a variety of cellular stimuli.

Animals↗

PubMed1998

Differential roles of ERK and p38 MAP kinase pathways in positive and negative selection of T lymphocytes.

Clonal selection of T lymphocytes is essential for establishing self/non-self discrimination of immune recognition. It is known that cell surface signals such as avidity and valency of TCR-ligand interactions influence the fate of individual thymocytes, founding a primary repertoire of T cells. However, intracellular signals that govern positive and negative selection in the thymus have been unclear. The present study using the retroviral gene transfer technique shows that MKK1 activation in developing T cells is sufficient for providing positive selection signals. We also show that the MKK6-p38 signaling pathway is critically involved in inducing negative selection of thymocytes. These results suggest that intracellular signals through different MAP kinase cascades selectively guide positive and negative selection of T lymphocytes.

Animals↗

PubMed1998

Functional relationship between age-related immunodeficiency and learning deterioration.

Disordered immune responses are supposed to alter the function of the central nervous system through the neuroendocrine immunomodulation network. In this paper, we studied the influence of the immune function on learning performances from the angle of pharmacology using aged garlic extract (AGE), an immunomodulator. Splenocyte proliferation, induced by concanavalin A or lipopolysaccharide, and the antibody production response were declined in senescence accelerated mouse-prone 8 (SAMP8) aged 12 months compared with age-matched SAMR1 (SAM-resistant 1). Chronic oral administration of AGE-containing food (2%, w/w) significantly enhanced the immune responses of both SAMP8 and SAMR1. Male ddY mice were thymectomized 4 weeks after birth and fed AGE-containing food after the operation until the experiments were finished. Learning performances, brain monoamine content and choline acetyltransferase (ChAT) activity, as well as the immune response were evaluated 10 months after the operation. Thymectomy resulted in not only immunodeficiency, but also deteriorated learning ability. AGE treatment prevented the reduction of the antibody production response induced by thymectomy and improved the thymectomy-induced deterioration of learning behaviours in passive avoidance performance and in a spatial memory task. The contents of hypothalamic noradrenaline, 3,4-dihydroxyphenylacetic acid and homovanillic acid, and the hypothalamic ChAT activity were increased in thymectomized mice compared to those of sham-operated control, while AGE treatment restored them to the control levels. These results suggest that the improvement of immune function is closely related to the amelioration of age-associated deterioration of learning and memory.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1998

Flow-through vascularized toe-joint transfer for reconstruction of segmental loss of an amputated finger.

A segmental finger defect was reconstructed in a 46-year-old woman with a free flow-through vascularized toe-joint, including the proximal interphalangeal joint, the plantar digital nerve, and tendons of the second toe. The advantages of this composite flap are: (1) The segmental loss of the finger can be easily reconstructed to achieve a normal anatomic structure. (2) Excellent cosmesis is achieved, compared with conventional flaps such as the groin flap. (3) The distal segment of the donor toe can be preserved. (4) The transected digital arteries of the amputated finger can be simultaneously reconstructed with a flow-through arterial interposition. (5) The digital nerve can be repaired with a vascularized plantar digital nerve graft.

Female↗

PubMed1998

Free combined anterolateral thigh flap and vascularized fibula for wide, through-and-through oromandibular defects.

Through-and-through oromandibular defects require the greatest amount of soft-tissue volume among the transfers for head and neck defects. A new method, a large anterolateral thigh flap combined with a vascularized fibula graft in a chimera fashion, has been used for two patients with wide through-and-through oromandibular defects. Among the candidates for such a large skin flap, the anterolateral thigh flap seems to be the best, for the following reasons. (1) Its pedicle, the lateral circumflex femoral system, has several major branches of equal size of anastomosis of the peroneal vessels. (2) As the majority of such patients with multiple previous surgery have lost recipient vessels near the mandible, the longest vascular pedicle is required. (3) There is no need for positional changes, and simultaneous flap elevation with the tumor resectioning is possible. (4) Use of the fibula allows for reconstruction of the entire mandible, if necessary. (5) Some of the shortcomings of individual donor sites for massive composite osteocutaneous flaps are minimized, because each component consists of two donor sites. (6) Operating time for this flap elevation is minimized, compared to that for massive composite osteocutaneous flaps, because the individual components can be obtained simultaneously by two teams.

Aged↗

PubMed1998

Paraumbilical perforator flap without deep inferior epigastric vessels.

With the introduction of supramicrosurgery, a new paraumbilical perforator flap without a deep inferior epigastric vessel and with very small perforator anastomoses was used for nine patients. The abdominal defects of two patients, the lower leg or foot defects of five patients, and the scalp defects of two patients were repaired with an island perforator flap. The advantages of the paraumbilical perforator flap are as follows: (1) there is a very short operating time for flap elevation; (2) there is no invasion or sacrifice of any rectus abdominis muscle; (3) for middle-aged, obese patients, the donor site may be the best from the cosmetic point of view; (4) many small recipient vessels to anastomose the perforator exist throughout the body; (5) a thin skin flap with adequate thickness can be created easily with simultaneous removal of fatty tissue; (6) secondary defatting around the perforator can be done by minor surgery under local anesthesia; and (7) a vascularized adiposal flap with adequate thickness can be created easily. This flap seems to be indicated for female patients with defects in the abdominal wall and the lower leg. The island flap can easily resurface abdominal skin defects, such as intestinal fistula or radiation ulcers. The free flap is suitable for covering defects in the lower leg, foot, and scalp temporarily before administration of a tissue expander.

Adolescent↗

PubMed1998

[Efficacy and safety of two methods of administration of granisetron injection for nausea and vomiting induced by chemotherapy for tumors in hematopoietic organs--a randomized crossover comparison between intravenous drip infusion and intravenous bolus injection].

We investigated the efficacy and safety of two methods of granisetron injection to treat nausea and vomiting induced by chemotherapy for tumors in hematopoietic organs. The methods of administration were intravenous drip infusion over 30 minutes, which is the conventional method, and intravenous bolus injection. In this study, 89.5% of patients in both groups (17/19 for each) were free from vomiting. No serious adverse events were observed in either administration group. Abnormal laboratory test values suspected to be related to granisetron were observed in 3 cases in the bolus injection group and in 2 cases in the drip infusion group. but did not pose any clinical problem. These results demonstrated the safety of both methods of administration. In conclusion, it is considered that granisetron intravenous bolus injection can be considered as the method of choice for the prevention of nausea and vomiting induced by chemotherapy for tumors in hematopoietic organs.

Adult↗

PubMed1997

A novel SAPK/JNK kinase, MKK7, stimulated by TNFalpha and cellular stresses.

Stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK), a member of the MAP kinase (MAPK) superfamily, is thought to play a key role in a variety of cellular responses. To date, SEK1/MKK4, one of the MAP kinase kinase (MAPKK) family of molecules, is the only SAPK/JNK kinase that has been cloned. Here we have cloned, identified and characterized a novel member of the mammalian MAPKKs, designated MKK7. MKK7 is most similar to the mediator of morphogenesis, hemipterous (hep), in Drosophila. Immunochemical studies have identified MKK7 as one of the major SAPK/JNK-activating kinases in osmotically shocked cells. While SEK1/MKK4 can activate both the SAPK/JNK and p38 subgroups of the MAPK superfamily, MKK7 is specific for the SAPK/JNK subgroup. MKK7 is activated strongly by tumour necrosis factor alpha (TNFalpha) as well as by environmental stresses, whereas SEK1/MKK4 is not activated by TNFalpha. Column fractionation studies have shown that MKK7 is a major activator for SAPK/JNK in the TNFalpha-stimulated pathway. Moreover, we have found that overexpression of MKK7 enhances transcription from an AP-1-dependent reporter construct. Thus, MKK7 is an evolutionarily conserved MAPKK isoform which is specific for SAPK/JNK, is involved in AP-1-dependent transcription and may be a crucial mediator of TNFalpha signalling.

Amino Acid Sequence↗

PubMed1997

Fas induces cytoplasmic apoptotic responses and activation of the MKK7-JNK/SAPK and MKK6-p38 pathways independent of CPP32-like proteases.

IL-1beta converting enzyme (ICE) family cysteine proteases are subdivided into three groups; ICE-, CPP32-, and Ich-1-like proteases. In Fas-induced apoptosis, activation of ICE-like proteases is followed by activation of CPP32-like proteases which is thought to be essential for execution of the cell death. It was recently reported that two subfamily members of the mitogen-activated protein kinase superfamily, JNK/SAPK and p38, are activated during Fas-induced apoptosis. Here, we have shown that MKK7, but not SEK1/ MKK4, is activated by Fas as an activator for JNK/ SAPK and that MKK6 is a major activator for p38 in Fas signaling. Then, to dissect various cellular responses induced by Fas, we used several peptide inhibitors for ICE family proteases in Fas-treated Jurkat cells and KB cells. While Z-VAD-FK which inhibited almost all the Fas-induced cellular responses blocked the activation of JNK/SAPK and p38, Ac-DEVD-CHO and Z-DEVD-FK, specific inhibitors for CPP32-like proteases, which inhibited the Fas-induced chromatin condensation and DNA fragmentation did not block the activation of JNK/SAPK and p38. Interestingly, these DEVD-type inhibitors did not block the Fas-induced morphological changes (cell shrinkage and surface blebbing), induction of Apo2.7 antigen, or the cell death (as assessed by the dye exclusion ability). These results suggest that the Fas-induced activation of the JNK/SAPK and p38 signaling pathways does not require CPP32-like proteases and that CPP32-like proteases, although essential for apoptotic nuclear events (such as chromatin condensation and DNA fragmentation), are not required for other apoptotic events in the cytoplasm or the cell death itself. Thus, the Fas signaling pathway diverges into multiple, separate processes, each of which may be responsible for part of the apoptotic cellular responses.

Apoptosis↗

PubMed1997

LOK is a novel mouse STE20-like protein kinase that is expressed predominantly in lymphocytes.

We have identified a new gene, designated lok (lymphocyte-oriented kinase), that encodes a 966-amino acid protein kinase whose catalytic domain at the N terminus shows homology to that of the STE20 family members involved in mitogen-activated protein (MAP) kinase cascades. The non-catalytic domain of LOK does not have any similarity to that of other known members of the family. There is a proline-rich motif with Src homology region 3 binding potential, followed by a long coiled-coil structure at the C terminus. LOK is expressed as a 130-kDa protein, which was detected predominantly in lymphoid organs such as spleen, thymus, and bone marrow, in contrast to other mammalian members of the STE20 family. LOK phosphorylated itself as well as substrates such as myelin basic protein and histone IIA on serine and threonine residues but not on tyrosine residues, establishing LOK as a novel serine/threonine kinase. When coexpressed in COS7 cells with the known MAP kinase isoforms (ERK, JNK, and p38), LOK activated none of them in contrast to PAK- and GCK-related kinases. These results suggest that LOK could be involved in a novel signaling pathway in lymphocytes, which is distinct from the known MAP kinase cascades.

Amino Acid Sequence↗

PubMed1997

Activation of p38 MAP kinase pathway by erythropoietin and interleukin-3.

Activation of p38 MAP kinase (p38) as well as JNK/SAPK has been described as being induced by a variety of environmental stresses such as osmotic shock, ultraviolet radiation, and heat shock, or the proinflammatory cytokines tumor necrosis factor-alpha and interleukin-1 (IL-1). We found that the hematopoietic cytokines erythropoietin (Epo) and IL-3, which regulate growth and differentiation of erythroids and hematopoietic progenitors, respectively, also activate a p38 cascade. Immunoblot analyses and in vitro kinase assay clearly showed that Epo and IL-3 rapidly and transiently phosphorylated and activated p38 in Epo- or IL-3-dependent mouse hematopoietic progenitor cells. p38 can generally be activated by the upstream kinase MKK3 or MKK6. However, in vitro kinase assays in the immunoprecipitates with anti-MKK6 antibody and anti-phosphorylated MKK3/MKK6 antibody showed that activation of neither MKK3 nor MKK6 was detected after Epo or IL-3 stimulation, while osmotic shock clearly induced activation of both MKK3/MKK6 and p38. Together with previous observations, these results suggest that both p38 and JNK cascades play an important role not only in stress and proinflammatory cytokine responses but also in hematopoietic cytokine actions.

Animals↗

PubMed1997

TAK1 mediates the ceramide signaling to stress-activated protein kinase/c-Jun N-terminal kinase.

Ceramide has been proposed as a second messenger molecule implicated in a variety of biological processes. It has recently been reported that ceramide activates stress-activated protein kinase (SAPK, also known as c-Jun NH2-terminal kinase JNK), a subfamily member of mitogen-activated protein kinase superfamily molecules and that the ceramide/SAPK/JNK signaling pathway is required for stress-induced apoptosis. However, the molecular mechanism by which ceramide induces SAPK/JNK activation is unknown. Here we show that TAK1, a member of the mitogen-activated protein kinase kinase kinase family, is activated by treatment of cells with agents and stresses that induce an increase in ceramide. Ceramide itself stimulated the kinase activity of TAK1. Expression of a constitutively active form of TAK1 resulted in activation of SAPK/JNK and SEK1/MKK4, a direct activator of SAPK/JNK. Furthermore, expression of a kinase-negative form of TAK1 interfered with the activation of SAPK/JNK induced by ceramide. These results indicate that TAK1 may function as a mediator of ceramide signaling to SAPK/JNK activation.

Animals↗