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T Sugimoto

Publications and source records attributed to T Sugimoto.

At least 163 records · Page 9Linked to original sources

An evolutionarily conserved G-protein coupled receptor family, SREB, expressed in the central nervous system.

We report here a novel family of G-protein coupled receptor (GPCR) which is extraordinarily conserved among vertebrate species. This family, designated SREB (Super Conserved Receptor Expressed in Brain), consists of at least three members, termed SREB1, SREB2, and SREB3. SREB members share 52-63% amino acid identity with each other and show relatively high similarity to previously known amine amine GPCRs (approximately 25% identity). Amino acid sequence identity between human and rat orthologues is 97% for SREB1 and 99% for SREB3, while the SREB2 sequence is surprisingly completely identical between the species. Furthermore, amino acid sequence of zebrafish SREB2 and SREB3 are 94 and 78% identical to mammal orthologues. Northern blot analysis revealed that SREB members are predominantly expressed in the brain regions and genital organs. Radiation hybrid analysis localized SREB1, SREB2, and SREB3 genes to different human chromosomes, namely 3p21-p14, 7q31 and Xp11, respectively. The high sequence conservation and abundant expression in the central nervous system suggest the existence of undiscovered fundamental neuronal systems consisting of SREB family members and their endogenous ligand(s).

Amino Acid Sequence↗

Neurocalcin-immunoreactive primary sensory neurons in the trigeminal ganglion provide myelinated innervation to the tooth pulp and periodontal ligament.

The distribution of neurocalcin-immunoreactive (NC-ir) primary sensory neurons was examined in the trigeminal ganglion (TG), mesencephalic trigeminal tract nucleus (Mes5) and intraoral structures. NC-ir primary sensory neurons were located in the TG but not the Mes5. The coexpression study demonstrated that virtually all NC-ir TG neurons exhibited S100-immunoreactivity (-ir). In the tooth pulp, NC-ir nerve fibers were observed in the subodontoblastic and odontoblastic layers. Immunoelectron microscopic and retrograde tracing methods revealed that myelinated pulpal axons derived from the TG mostly exhibited the ir. In the periodontal ligament, bush-like endings showed NC-ir. These endings were morphologically identical to Ruffini-like endings. The present study suggests that NC-ir trigeminal primary sensory neurons have their cell bodies in the TG. Their peripheral axons are probably myelinated. Such neurons include pulpal nociceptors and low-threshold mechanoreceptors.

Animals↗

The novel G-protein coupled receptor SALPR shares sequence similarity with somatostatin and angiotensin receptors.

A cDNA encoding a novel G-protein coupled receptor (GPCR) was isolated from a human cerebral cortex cDNA library by low stringency hybridization screening. This putative seven-transmembrane domain receptor of 469 amino acids was designated SALPR (Somatostatin- and Angiotensin- Like Peptide Receptor). SALPR shares the highest amount of amino acid similarity with the somatostatin (35% with SSTR5) and angiotensin receptors (31% with AT1). Reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that the SALPR mRNA is predominantly expressed in human brain regions, particularly the substantia nigra and pituitary, although the mRNA can also be detected in the peripheral tissues, albeit at low levels. Chromosomal mapping by radiation hybrid analysis localized the human SALPR gene to the chromosome 5p15.1-5p14. Transient expression of SALPR in COS-1 cells did not produce any binding sites for somatostatin or angiotensin II, indicating the necessity for further study to discover its ligand and physiological significance.

Amino Acid Sequence↗

Osteopontin-immunoreactive primary sensory neurons in the rat spinal and trigeminal nervous systems.

1200 micrometer(2) and 9% of those in the range 600-1200 micrometer(2) showed the immunoreactivity (ir). DRG neurons <600 micrometer(2)800 micrometer(2) showed the ir and 21% of those in the range 400-800 micrometer(2) were immunoreactive for this protein. TG neurons <400 micrometer(2) were mostly devoid of OPN-ir (2%). Virtually all (99%) Mes5 primary sensory neurons exhibited the ir. Muscle spindles in the soleus and masseter muscles contained OPN-ir spiral axon terminals. In the hard palate and incisor periodontal ligament, unencapsulated corpuscular endings exhibited the ir. The co-expression of OPN with parvalbumin and calcitonin gene-related peptide (CGRP) was also examined in the DRG and TG. In the DRG, virtually all (97%) OPN-ir neurons exhibited parvalbumin-ir. Conversely, 66% of parvalbumin-ir DRG neurons co-expressed OPN-ir. In the TG, 81% of OPN-ir neurons exhibited parvalbumin-ir and 69% of parvalbumin-ir ones showed OPN-ir. Virtually all OPN-ir DRG and TG neurons were devoid of CGRP-ir. The present study indicates that OPN-ir primary sensory neurons in the DRG and Mes5 are spinal and trigeminal proprioceptors. OPN-ir TG neurons appear to include low-threshold mechanoreceptors.

Animals↗

2,2'-Spirobi(1,3-benzodithiole).

The X-ray structure analysis of 2,2'-spirobi(1,3-benzodithiole), C(13)H(8)S(4), has been performed. The molecule has crystallographic twofold rotation symmetry, the axis passing through the spiro-C atom. The four S atoms are arranged around the spiro-C atom in two almost orthogonal CS(2) planes. However, because of large bending of the two five-membered rings, close contact is present between two connected C atoms on the benzo group of each 1,3-benzodithiole ring and one S atom on the other 1,3-benzodithiole ring.

Journal Article↗

The difference in temporal distribution of c-Fos immunoreactive neurons between the medullary dorsal horn and the trigeminal subnucleus oralis in the rat following experimental tooth movement.

The difference in temporal distribution of c-Fos-immunoreactivity (Fos-IR) was assessed in the medullary dorsal horn (MDH) and in the dorsomedial part of the trigeminal subnucleus oralis (Vodm) following experimental tooth movement of the rat maxillary molars. The number of MDH c-Fos-immunoreactive neurons increased bilaterally at 2 h and decreased markedly by 12 h, and then increased again with a small peak at 48 h. In contrast, Vodm c-Fos expression was not up-regulated until 12 h, but increased in number after 24 h, which increase lasted until 72 h. These findings indicate that experimental tooth movement induced nociceptive c-Fos response in a biphasic manner. Furthermore, the later response appeared after 24 h, and lasted for a few days, mainly manifested in the Vodm during experimental tooth movement.

Animals↗

The effect of neonatal capsaicin on the c-Fos-like immunoreactivity induced in subnucleus oralis neurons by noxious intraoral stimulation.

The noxious stimulus-dependent induction of c-Fos-like immunoreactivity (Fos-LI) in neurons in the subnucleus oralis and the medullary dorsal horn (MDH) was significantly suppressed by the selective destruction of unmyelinated primary neurons. The induction of Fos-LI by topical capsaicin application to the lingual mucosal stimulation was almost completely suppressed by neonatal capsaicin treatment. Fos-LI induction by the tooth pulp stimulation and by formalin injection to the lingual mucosa were only partially reduced. These results provide an evidence that the noxious signals from the intraoral structures are transmitted by both unmyelinated and myelinated nociceptors to the subnucleus oralis as well as the MDH.

Animals↗

Zic2 regulates the kinetics of neurulation.

Mutation in human ZIC2, a zinc finger protein homologous to Drosophila odd-paired, causes holoprosencephaly (HPE), which is a common, severe malformation of the brain in humans. However, the pathogenesis is largely unknown. Here we show that reduced expression (knockdown) of mouse Zic2 causes neurulation delay, resulting in HPE and spina bifida. Differentiation of the most dorsal neural plate, which gives rise to both roof plate and neural crest cells, also was delayed as indicated by the expression lag of a roof plate marker, Wnt3a. In addition the development of neural crest derivatives such as dorsal root ganglion was impaired. These results suggest that the Zic2 expression level is crucial for the timing of neurulation. Because the Zic2 knockdown mouse is the first mutant with HPE and spina bifida to survive to the perinatal period, the mouse will promote analyses of not only the neurulation but also the pathogenesis of human HPE.

Animals↗

Developmental dependency of Meissner corpuscles on trkB but not trkA or trkC.

The distribution of S100-immunoreactive (ir) corpuscular endings was examined in the palate of wildtype and knockout mice for trkA, trkB or trkC. In wildtype mice, S100-ir corpuscular endings were abundant at the top of palatal rugae. The endings contained 2-4 parallel arrays of S100-ir neurites. The distribution of S100-ir nerve endings in trkA and trkC knockout mice was similar to that in wildtype mice; S100-ir corpuscular endings were abundant in palates of the mutant mice. In trkB knockout mice, the palate was devoid of corpuscular endings, An immunoelectron microscopic method indicated that S100-ir corpuscular endings were identical to Meissner corpuscles. The normal development of Meissner corpuscles is probably dependent on trkB but not trkA or trkC.

Animals↗

Quantitation of minimal residual disease in t(8;21)-positive acute myelogenous leukemia patients using real-time quantitative RT-PCR.

t(8;21) is one of the common chromosomal translocations in acute myelogenous leukemia (AML). Using a recently developed real-time quantitative polymerase chain reaction (PCR) system, we analyzed the minimal residual disease (MRD) in bone marrow samples from seven AML patients with t(8;21) at different time points during the clinical courses of their disease. Four of these patients received chemotherapy and allogenic bone marrow transplantation (allo-BMT), and the other three were treated with chemotherapy alone. Two of the patients that received allo-BMT suffered a relapse. In these patients, the levels of AML1-MTG8 mRNA expression were shown to quantitatively increase. After re-induction chemotherapy and donor lymphocyte infusion therapy, AML went into remission and the expression levels decreased. In the other two patients receiving allo-BMT, the disease went into remission and the level of AML1-MTG8 mRNA expression remained under the detectable range. The other three patients received several courses of chemotherapy, without allo-BMT, and all of them clinically reached the hematological and cytogenetic remission state. However, there were low but detectable levels of MRD in their bone marrow samples. These results suggest that the real-time quantitative PCR assay is very useful for the monitoring of MRD and detecting an early relapse. This assay may also be useful in determining the quantitative difference in myelo-ablative activity between the chemotherapy alone and chemotherapy in conjunction with allo-BMT.

Adult↗

Neuronal differentiation in human neuroblastoma cells by nerve growth factor following TrkA up-regulation by interferon-gamma.

BACKGROUND: TrkA mRNA expression has been reported to be related to favorable outcome of neuroblastoma (NB). Previously, we found that interferon-gamma (IFN-gamma) can enhance TrkA mRNA expression in NB cell lines. In the present study, we examined the effect of nerve growth factor (NGF) on IFN-gamma-induced TrkA protein to clarify the relationship between TrkA and cell differentiation of NB. PROCEDURE: The effect of IFN-gamma on the TrkA mRNA expression was screened in six human NB cell lines and a freshly prepared sample, SK-rib, from a stage IV patient. Using two of them, we examined their morphological change during simultaneous loading of NGF and IFN-gamma. Tyrosine phosphorylation pattern after 5 min of NGF stimulation was also examined in immunoblot analysis with anti-gp140(trkA) antibody and antiphospho tyrosine antibody. RESULTS: After a 4-day treatment with 500 IU/ml IFN-gamma, TrkA mRNA increased in five cell lines and SK-rib cells in association with growth inhibition. Although the degree of morphological differentiation did not increase in proportion to the TrkA expression induced by IFN-gamma, continuous loading of both IFN-gamma and NGF caused marked morphological differentiation in a cultured KP-N-RT cell line and SK-rib cells during 10 days. Moreover, 5 min of NGF stimulation after IFN-gamma treatment caused the phosphorylation of TrkA protein and downstream proteins. CONCLUSIONS: IFN-gamma could induce the functional NGF receptor even in the aggressive phenotype of NB.

Antineoplastic Agents↗

Compensatory projection of primary nociceptors and c-fos induction in the spinal dorsal horn following neonatal sciatic nerve lesion.

The sciatic nerve was cut in newborn rats, and prevented from regenerating for 8 weeks. The number of dorsal root ganglion (DRG) neurons in L4 and L5, the distribution of central axon terminals of primary nociceptors, and the activity of secondary nociceptors were examined in the lumbar dorsal horn. The neonatal sciatic lesion caused about 60% reduction of DRG neurons. The central terminal field of the sciatic primary nociceptors negatively labeled by in situ binding of Bandeiraea simplicifolia isolectin B4 (BsIB4) markedly shriveled. Instead, the central representation of the saphenous nerve and the posterior cutaneous nerve of the thigh (PC) expanded. The laminae I/II neuropil in the medialmost (1/4) of the L3 dorsal horn and in the second lateral (1/4) around the L4/5 junction was occupied by the BsIB4 binding sites derived from the saphenous and the PC primary neurons, respectively. Noxious stimuli applied to the receptive fields of the saphenous and the PC nerves induced c-Fos-like immunoreactivity in many neurons in the expanded central terminal fields of the nerves. The collateral sprouts of uninjured primary nociceptors did not only invade the deafferented area of the dorsal horn but also established functional synaptic connections.

Afferent Pathways↗

Leukemic hypopyon in acute myelogenous leukemia.

We encountered a patient with acute myelogenous leukemia (AML) who developed leukemic hypopyon. Leukemia initially spread into the pharynx, gingiva, lymphnode, and bone marrow. He achieved complete remission after chemotherapy but developed blurred vision and hypopyon. Anterior chamber paracentesis disclosed leukemic infiltration of the anterior chamber. Infiltration of the central nervous system also occurred. He received systemic chemotherapy, intrathecal chemotherapy, and local chemotherapy. However, he did not achieve prolonged remission. These findings suggest that these chemotherapy treatments have an inadequate effect for AML with anterior chamber infiltration. This rare complication is associated with extramedullary infiltration of leukemia.

Anterior Chamber↗

Stromal sarcoma of the breast with lung metastasis successfully treated by radiotherapy: report of a case.

We report herein the case of a 42-year-old woman in whom a solitary lung metastasis from stromal sarcoma of the breast was effectively treated by radiotherapy. The original breast tumor had been extirpated in a local hospital, and she was subsequently referred to our outpatient clinic for nonsurgical treatment. Pathological examination of the breast tumor had confirmed a diagnosis of stromal sarcoma. Radiation and systemic chemotherapy for the remnant disease were administered at our hospital; however, 8 months later, local recurrence and a solitary lung metastasis were recognized on a chest X-ray. A second lumpectomy of the recurrent breast tumor along with radiation for the lung metastasis and systemic chemotherapy were performed. After a 4-year disease-free period, there is still no sign of recurrence. This case serves to demonstrate the effectiveness of radiotherapy for the treatment of lung metastasis from stromal sarcoma of the breast.

Adult↗

Tension hemothorax caused by a ruptured aneurysm of the descending thoracic aorta: report of a a case.

The rupture of an aneurysm of the descending thoracic aorta into the right thoracic cavity is a comparatively rare event, and it is very difficult to establish a diagnosis immediately and rescue such patients. We describe herein the successful surgical treatment of a patient with this life-threatening emergency by initiating immediate cardiopulmonary bypass. It is mandatory to drain the right thoracic bleeding through a left thoracotomy without delay to release the tension hemothorax. Furthermore, it is necessary to evacuate the right thoracic hematoma through a right thoracotomy because complete removal o f a hugh hematoma through a left thoracotomy cannot be effectively achieved.

Aged↗

Intraoperative map guided operation for atrial fibrillation due to mitral valve disease.

BACKGROUND: This study was designed to determine if intraoperative atrial activation mapping facilitates operations for chronic atrial fibrillation associated with mitral valve disease. METHODS: Surgical treatment guided by intraoperative electrophysiologic mapping was performed in 12 patients with chronic atrial fibrillation associated with isolated mitral valve disease. In 10 of 12 patients, regular and repetitive activation (cycle length ranged from 118 to 210 msec) originated in the left atrial appendage and/or orifice of the left pulmonary vein. In the remaining 2 patients, dominant repetitive activation and sporadic complex activation were alternately observed in the left atrium. However, the activation sequence of the right atrium was extremely complex and chaotic. RESULTS: On the basis of intraoperative mapping, surgical procedures, including resection of the left atrial appendage and/or cryoablation of the orifice of the left pulmonary vein, were applied on the breakthrough site of the repetitive activation. No surgical procedure was performed on the right atrium in 11 patients. Ten of 12 patients (83%) have maintained sinus rhythm for 6 to 40 months (average 24.8 months) after operation. CONCLUSIONS: In the majority of the patients with isolated mitral valve disease, the left atrium acts as an electrical driving chamber for chronic atrial fibrillation. Computerized intraoperative mapping should guide surgeons in determining the appropriate surgical procedure for chronic atrial fibrillation.

Aged↗

Trophoblastic cells expressing human chorionic gonadotropin genes in peripheral blood of patients with trophoblastic disease.

We attempted to identify the cells expressing alpha and beta subunits of human chorionic gonadotropin (hCG) in the peripheral blood of patients with trophoblastic disease and normal pregnant women by using reverse transcriptase polymerase chain reaction (RT-PCR) and Southern blot. By this method, the mRNAs of hCG alpha and hCG beta were detected in the peripheral blood mononulear cells (PBMNC) from 3 of 7 hydatidiform mole (mole) and 1 of 4 choriocarcinoma patients as well as from normal pregnant women during the first trimester. None of the mRNAs of hCG subunits was detected in the PBMNC from healthy male and nonpregnant healthy women examined. The expression of hCG alpha and hCG beta in patients with trophoblastic disease and normal pregnant women almost correlated with their plasma levels of intact hCG. The present study indicates that the cells expressing hCG alpha and hCG beta, which virtually represent trophoblasts, are circulating in the peripheral blood of patients with trophoblastic disease as well as of normal pregnant women.

Blotting, Southern↗