Biomedical subjects

K Yamashiro

Publications and source records attributed to K Yamashiro.

At least 19 recordsLinked to original sources

PubMed2005

Isolation and expression of FIP-2 in wounded pulp of the rat.

Pulpal wound healing followed by cavity preparation may involve reactionary or reparative dentinogenesis in relation to the cavity position; however, little is known about the molecular responses. We aimed to isolate and analyze genes induced or suppressed in the wounded pulp to identify molecular processes involved in the pulp responses to injury. Twenty-three cDNAs were isolated by cDNA subtraction between healthy and wounded pulp of rats. By library screening, we identified rat 14.7K-interacting protein (rFIP)-2A and B genes homologous to human FIP-2, being involved in regulating membrane trafficking and cellular morphogenesis. RT-PCR analysis showed induction for only rFIP-2B in the wounded pulp. In situ hybridization analysis revealed that both rFIP-2s were expressed strongly in condensing mesenchymal cells of the palatal process and surrounding Meckel's cartilage, but not in intramembranous chondrogenic cells. Thus, up-regulated rFIP-2B expression may play a role in regulating membrane trafficking or cellular morphogenesis of these embryonic and wounded pulpal cells.

Amino Acid Sequence↗

PubMed2004

Telecytology in Hokkaido Island, Japan: results of primary telecytodiagnosis of routine cases.

In 1997, an Internet-based static image telepathology system was built at Sapporo National Hospital, Japan. We can exchange high-resolution microscopical images through a file transfer protocol server and discuss cytological findings and diagnosis on an electronic mailing list. We applied the system to primary telecytodiagnosis. From May 1997 to April 1999 we have made diagnoses of 614 daily cases only by looking at the video monitor images transmitted from the cytotechnologist of Wakkanai Municipal Hospital 300 km distant from Sapporo. The concordance between telecytodiagnosis and glass slide diagnosis was 88.6%. Kappa statistics for cervical smears was 0.919 and that for specimens other than uterine cervix was 0.810. The accuracy of telecytodiagnosis was 91.4%, and was not substantially different from that of the conventional mail-based cytology in a previous year. We had five cases with a severely inappropriate diagnosis in telecytology, all of which however were quickly corrected by follow-up histological or cytological specimens. With the use of an electronic mailing list the participants had quick and sufficient discussions. We conclude that telecytology is very useful for primary cytodiagnosis in regional medicine and that it may raise the accuracy of cytodiagnosis in future, if we make consistent efforts to reflect the benefits of telecytology in daily practices. This is the first report of clinical results of telecytology from Japan.

Clinical Laboratory Techniques↗

PubMed2004

Identification of genes differentially regulated in rat alveolar bone wound healing by subtractive hybridization.

Periodontal healing requires the participation of regulatory molecules, cells, and scaffold or matrix. Here, we hypothesized that a certain set of genes is expressed in alveolar bone wound healing. Reciprocal subtraction gave 400 clones from the injured alveolar bone of Wistar rats. Identification of 34 genes and analysis of their expression in injured tissue revealed several clusters of unique gene regulation patterns, including the up-regulation at 1 wk of cytochrome c oxidase regulating electron transfer and energy metabolism, presumably occurring at the site of inflammation; up-regulation at 2.5 wks of pro-alpha-2 type I collagen involving the formation of a connective tissue structure; and up-regulation at 1 and 2 wks and down-regulation at 2.5 and 4 wks of ubiquitin carboxyl-terminal hydrolase l3 involving cell cycle, DNA repair, and stress response. The differential expression of genes may be associated with the processes of inflammation, wound contraction, and formation of a connective tissue structure.

Alveolar Process↗

PubMed2003

Neurons with spontaneous high-frequency discharges in the central nervous system and chronic pain.

Neurons with high-frequency discharge (hyperactive neuron) were recorded in the thalamus of chronic pain patients. We created a chronic pain rat model, and recorded the discharge of high-frequency neurons by using a microelectrode in the thalamic area. The character of these high-frequency discharge neurons was assessed. Deep brain stimulation (DBS) was done in 9 patients, and motor cortical stimulation (MCS) in 2. Prior to implantation of the stimulation electrodes, extracellular unitary activity was recorded and local microstimulation was done by the same microelectrode. From the ventrocaudal (Vc) nucleus of the chronic pain patients, hyperactive neurons were recorded. There were three types of discharge patterns in interval histograms. Some hyperactive neurons showed firing suppression for a short time period by intravenous administration of phenytoin and calcium antagonist (Nicardipine). In animal experiments, unilateral dorsal root sectioning from C5 to Th1 were made in male Wistar rats according to the method of Lombard et al. (1979). A few months after the operation, hyperactive neurons were recorded from the thalamic nuclei and lemniscus medialis. The firing patterns and distribution of hyperactive neurons were very similar to those of humans. Sensorimotor cortical electrical stimulation showed a reduction of firing in the hyperactive neurons. Iontophoretical application of glutamate yielded an increase in firing. In contrast, GABA and NMDA antagonist MK-801 revealed remarkable firing suppression. These results suggest that hyperactive neurons may correlate with the glutamatergic, especially NMDA and GABAergic receptor or fibers.

Action Potentials↗

PubMed2003

Suppressive effects of selectin inhibitor SKK-60060 on the leucocyte infiltration during endotoxin induced uveitis.

BACKGROUND: It is well known that selectin is involved in the development of endotoxin induced uveitis (EIU), and has a major role in leucocyte infiltration. Recently, a novel selectin inhibitor (SKK-60060) that can block P and L selectins in vitro has been developed. This study was designed to investigate the anti-inflammatory effects of SKK-60060 on the inflammatory reaction during EIU in rats by studying leucocyte-endothelium interactions. METHODS: EIU was induced in Lewis rats by footpad injection of lipopolysaccharide (LPS). SKK-60060 was administered 15 minutes before LPS injection, and its suppressive effects on inflammatory leucocyte behaviour were evaluated in vivo with acridine orange digital fluorography; the diameters of retinal arteries and veins were also measured. After these studies, aqueous humour was collected to evaluate leucocyte infiltration and protein leakage. RESULTS: After LPS injection, rolling leucocytes were observed in major retinal veins, followed by leucocyte infiltration into the vitreous cavity. Following treatment with SKK-60060, leucocyte rolling was significantly inhibited in the retinal veins (p <0.01), and subsequent leucocyte infiltration into the vitreous cavity was also significantly suppressed (p <0.01). Retinal vasodilation was also substantially suppressed in SKK-60060 treated rats (p <0.01). Similarly, leucocyte infiltration and protein leakage into the aqueous humour were reduced significantly by SKK-60060 (p <0.01). CONCLUSIONS: SKK-60060 treatment significantly inhibited the inflammatory reaction induced by LPS. Its inhibitory effects on P and L-selectin resulted in suppression of leucocyte infiltration and the subsequent inflammatory reaction caused by accumulated leucocytes. The current findings suggest that SKK-60060 may be useful in the management of uveitis.

Animals↗

PubMed2003

Gene profiling in human periodontal ligament fibroblasts by subtractive hybridization.

Genes expressed by human periodontal ligament fibroblasts (HPFs) are likely to be associated with specific functions of the ligament. The aim of this study is to profile genes expressed highly by HPFs. A library (6 x 10(3) pfu) was constructed, followed by subtraction of HPF cDNAs with human gingival fibroblast (HGF) cDNAs. Reverse-dot hybridization revealed that 33 clones expressed higher levels of specific mRNAs in HPFs than in HGFs. These were mRNAs for known genes, including several associated with maturation and differentiation of cells. None had been reported in PFs. One clone, PDL-29, identified as a COX assembly factor, showed much stronger mRNA expression in HPFs than in HGFs in culture. In rat periodontium, however, PDL-29 mRNA expression was similar in PFs and GFs. These results suggest that HPFs express many previously unreported genes associated with maturation and differentiation, but expression can differ in vitro and in vivo.

Animals↗

PubMed2001

Suppressive effects of histamine H1 receptor antagonist diphenhydramine on the leukocyte infiltration during endotoxin-induced uveitis.

Histamine has been shown to play an important role in the step of leukocyte rolling, the initial step to leukocyte infiltration into an inflamed region. We investigated the roles of histamine in the leukocyte recruitment during endotoxin-induced uveitis (EIU) in vivo using acridine orange digital fluorography. An injection of histamine into the vitreous cavity of a Lewis rat induced leukocyte rolling along the major retinal veins. In other experiments, EIU was induced in Lewis rats by footpad injection of lipopolysaccharide (LPS). Leukocyte rolling was also observed in the retinal veins of EIU rats. To block the histamine H1 receptor, diphenhydramine (DPH) was administered intraperitoneally 15 min before the LPS injection. DPH significantly inhibited leukocyte rolling along the major retinal veins of EIU rats, suppressing leukocyte infiltration into the vitreous cavity. The vasodilation in EIU was also significantly suppressed with DPH. Moreover, leukocyte infiltration into aqueous humor was significantly suppressed in DPH-treated rats. Although the inhibitory effects of DPH was less obvious at later time points, addition of DPH every 12 hr showed prolonged anti-inflammatory effects up to 48 hr after LPS injection. In contrast, protein leakage into the aqueous humor was not suppressed as much as leukocyte infiltration with DPH. These results suggest that histamine would play a pivotal role in leukocyte recruitment during EIU in rats. Blocking the histamine H1 receptor might help to prevent or minimize leukocyte infiltration in uveitis.

Animals↗

PubMed2001

Pars plana vitrectomy for cystoid macular edema secondary to sarcoid uveitis.

OBJECTIVE: To examine the results of pars plana vitrectomy for cystoid macular edema secondary to sarcoid uveitis resistant to medical treatment. DESIGN: Retrospective, interventional, noncomparative case series. SUBJECTS: Fourteen consecutive subjects (18 eyes) with cystoid macular edema associated with sarcoid uveitis resistant to medical treatment. INTERVENTION: All eyes underwent pars plana vitrectomy. Nine eyes also underwent peeling of the epiretinal membrane or removal of the posterior vitreous cortex. MAIN OUTCOME MEASURES: Status of macular edema, visual acuity, and complications. RESULTS: Ten eyes (56%) improved 2 or more lines of Snellen visual acuity within 12 months. Six eyes (33%) remained unchanged, within a line of preoperative Snellen visual acuity, and two eyes (11%) worsened by 2 or more lines of Snellen visual acuity. Slit-lamp biomicroscopy showed that cystoid macular edema had resolved in 14 eyes (78%) within 9 months postoperatively. One eye (6%) had minimal edema, whereas three eyes (17%) remained unchanged biomicroscopically at the final visit. Postoperative complications included cataract formation, glaucoma, optic nerve atrophy, epiretinal membrane formation, and tractional retinal detachment. No severe postoperative inflammation was noted. CONCLUSIONS: Pars plana vitrectomy seems to have a beneficial effect on cystoid macular edema caused by sarcoidosis resistant to medical treatment.

Adult↗

PubMed2001

Sensitive assay to detect thyroid stimulating antibody (TSAb) in the presence of thyroid stimulation blocking antibody (TSBAb) in serum.

The detection of thyroid stimulating antibody (TSAb) activity in the presence of thyroid stimulation blocking antibody (TSBAb) in Graves' serum is difficult because TSBAb blocks TSAb activity. We recently demonstrated that polyethylene glycol (PEG) augments TSAb activity in porcine thyroid cells (PTC) assay. This PEG-induced augmentation makes it possible to develop a sensitive assay to detect TSAb in the presence of TSBAb. We studied the effects of PEG on TSAb- and TSBAb-activities in PTC using 4 different preparations of the samples; (1) crude IgG using PEG 22.5% precipitated fraction (PF) from Graves' serum (0.2 ml), (2) crude IgG using PEG 12.5% PF, (3) serum (50 microl), and (4) serum (50 microl) in the presence of 5% PEG (final). When the effects of PEG on TSAb activity using crude IgG were examined, PEG 22.5% PF showed significantly higher TSAb activity than PEG 12.5% PF as reported previously. The augmentative effect of PEG on TSAb activity was also observed by the addition of 5% PEG to serum. We also demonstrated that PEG augmented TSAb-activities even in TSBAb-positive serum by two methods (crude IgG using PEG 22.5% PF and the addition of 5% PEG to serum). TSBAb activities were expressed by two calculation methods (A= [1 - (a - b)/(c - d) x 100] and B = [1 - (a - d)/(c - d) x 100], where a is cAMP produced in the presence of bTSH and patient's IgG, b is cAMP produced in the presence of patient's IgG, c is cAMP produced in the presence of bTSH and normal IgG, and d is cAMP produced in the presence of normal IgG). In the presence of TSAb, the values of A method were always higher than those of B method, since TSAb stimulated cAMP synthesis. We have developed two sensitive methods to detect TSAb even in the presence of TSBAb in serum using PEG; 1) incubation of crude IgG using PEG 22.5% PF from serum (0.2 ml), and 2) co-incubation of 5 % PEG with test serum (50 microl).

Animals↗

PubMed2001

TSBAb (TSH-stimulation blocking antibody) and TSAb (thyroid stimulating antibody) in TSBAb-positive patients with hypothyroidism and Graves' patients with hyperthyroidism.

There are two types of TSH receptor antibodies (TRAb); thyroid stimulating antibody (TSAb) and TSH-stimulation blocking antibody (TSBAb). TSAb causes Graves' hyperthyroidism. TSBAb causes hypothyroidism. Both TSAb and TSBAb block TSH-binding to thyroid cells as TSH receptor antibodies (TRAb). TSBAb-positive patients with hypothyroidism and Graves' patients with hyperthyroidism may have both TSBAb and TSAb. We studied TSBAb and TSAb in 43 TSBAb-positive patients with hypothyroidism and in 55 untreated Graves' patients with hyperthyroidism. TSBAb-activities were expressed as percentage inhibition of bovine (b) TSH-stimulated cAMP production by test IgG. Two formulas were used to calculate TSBAb-activities; TSBAb-A (%) = [1 - (c - b)/(a - b)] x 100 and TSBAb-B (%) = [1 - (c - d)/(a - b)] x 100, where a: cAMP generated in the presence of normal IgG and bTSH, b: cAMP generated in the presence of normal IgG, c: cAMP generated in the presence of test IgG and bTSH, and d: cAMP generated in the presence of test IgG. TSAb (%) = [d/b] x 100. All of the 43 TSBAb-positive patients with hypothyroidism had strongly positive TSBAb-A and -B. Some of them had weakly positive TSAb (<240%). All 55 untreated Graves' patients had positive TSAb (205-2509%). Some of them had both TSAb and TSBAb. TSBAb-positive patients with hypothyroidism had a limited distribution of TSBAb- and TSAb-activities (TSBAb-A + 75 - + 103%, TSBAb-B + 87 - + 106%, TSAb 92-240%), but Graves' patients with hyperthyroidsim had a wide distribution of TSAb- and TSBAb-activities (TSAb 205-2509%, TSBAb-A - 158 - + 43%, TSBAb-B - 14 - + 164%). TSBAb-A ignores TSAb activity in serum, and might give low TSBAb activity. However, TSBAb-A clearly differentiates TSBAb-positive patients with hypothyroidism from Graves' patients with hyperthyroidism; thus, we favor TSBAb-A over TSBAb-B. Some of TSBAb-positive patients with hypothyroidism and Graves' patients with hyperthyroidism have both TSBAb and TSAb.

Adult↗

PubMed2001

Carcinosarcoma of the tongue with cyclin D1 gene amplification.

Carcinosarcoma of the tongue is a rare malignancy and its molecular aspect is unclear. A case of carcinosarcoma of the tongue in a 51-year-old man is presented. A polypoid tumor of the tongue, measuring 12 x 12 x 6 mm, was resected. Histologically, the tumor was composed of a squamous cell carcinoma and a spindle cell sarcomatous component. We previously showed that one cell-cycle regulator, the cyclin D1 gene, was frequently amplified in esophageal carcinosarcoma, which shows the same morphologic features as carcinosarcoma of the tongue. In this case, we examined whether the cyclin D1 gene is amplified in carcinosarcoma of the tongue as well. Fluorescence in situ hybridization analysis revealed that the cyclin D1 gene was amplified in both components of carcinosarcoma of the tongue. The cyclin D1 protein was also detected by immunostaining in both components. Our results suggest that the amplification of cyclin D1 gene plays a role in the molecular pathogenesis of carcinosarcoma of the tongue, at least in some cases.

Carcinosarcoma↗

PubMed2001

Inhibitory effects of antithrombin III against leukocyte rolling and infiltration during endotoxin-induced uveitis in rats.

PURPOSE: This study was designed to investigate the suppressive effects of antithrombin (AT)III on inflammatory reactions during endotoxin-induced uveitis (EIU) in rats by studying leukocyte-endothelium interactions. METHODS: EIU was induced in Lewis rats by footpad injection of lipopolysaccharide (LPS). ATIII was administered immediately after or at 6 hours after LPS injection. Its suppressive effects on inflammatory leukocyte behavior were evaluated in vivo with acridine orange digital fluorography. Clinical signs of inflammation were also examined, and aqueous humor (AH) was collected to evaluate leukocyte infiltration and protein leakage. In a separate experiment, P-selectin mRNA expression was studied in the iris-ciliary body (ICB) and the retina. RESULTS: After treatment with ATIII, leukocyte rolling was substantially inhibited along the retinal veins, suppressing subsequent leukocyte infiltration into the vitreous cavity. Similarly, leukocyte infiltration and protein leakage into the AH were significantly reduced with ATIII treatment. The clinical grade of EIU was substantially lower in ATIII-treated rats. In addition, delayed administration of ATIII after EIU induction significantly attenuated these inflammatory reactions. The levels of P-selectin mRNA expression in both ICB and retina, which were upregulated after LPS injection, were substantially lower in the ATIII-treated rats. CONCLUSIONS: ATIII treatment significantly inhibited inflammatory reactions induced with LPS. Its suppressive effects on P-selectin expression could contribute to the attenuation of leukocyte infiltration, possibly by inhibiting leukocyte rolling. The current findings suggest that ATIII may have a role in the management of patients with uveitis.

Animals↗

PubMed2001

In vivo evaluation of platelet--endothelial interactions after transient retinal ischemia.

PURPOSE: Accumulating evidence suggests that platelets play an important role in ischemia-reperfusion injury. To fulfill that role, platelets flowing in the bloodstream would have to interact with retinal endothelial cells and to accumulate in the postischemic retina. This study was designed to investigate quantitatively platelet-endothelial interactions in postischemic retina after transient retinal ischemia. METHODS: Transient retinal ischemia was induced in Long-Evans rats for 60 minutes by temporal ligation of the optic nerve. Isolated platelet samples labeled with carboxyfluorescein diacetate succinimidyl ester were administered intravenously to recipient rats after various reperfusion periods. Platelet-endothelial interactions in postischemic retina were evaluated in vivo with a scanning laser ophthalmoscope. Anti-P-selectin monoclonal antibody (mAb) was administered 5 minutes before the injection of labeled platelets. P-selectin gene expression in the postischemic retina was studied by semiquantitative polymerase chain reaction. RESULTS: Under basal conditions, infused platelets showed minimal interactions with retinal endothelial cells. In contrast, postischemic retinas showed active platelet-endothelial interactions. Many platelets were observed rolling along and adhering to the major retinal veins. The number of rolling and adhering platelets reached a peak (555 +/- 65/mm per min and 25.8 +/- 3.2/mm(2)) 12 hours after reperfusion. However, the interactions between platelets and postischemic retinal endothelial cells were substantially inhibited by neutralizing P-selectin expressed on endothelial cells. In addition, P-selectin gene expression in postischemic retina corresponded with the time course of platelet-endothelial interactions during the reperfusion period. CONCLUSIONS: This study demonstrated that platelets actively interacted with retinal endothelial cells in the postischemic retina through P-selectin expressed on the retinal endothelial cells.

Animals↗

PubMed2001

Inhibitory effect of ischemic preconditioning on leukocyte participation in retinal ischemia-reperfusion injury.

PURPOSE: Recent reports have shown that ischemic preconditioning induces strong protection against retinal damage by subsequent prolonged ischemia and that this protection is mediated by mechanisms involving the adenosine A1 receptor. This study was designed to evaluate quantitatively the effects of ischemic preconditioning on leukocyte-mediated reperfusion injury after transient retinal ischemia and to define the role of the adenosine A1 receptor in these effects. METHODS: Transient retinal ischemia was induced in male rats by temporary ligation of the optic nerve. Ischemic preconditioning (5 minutes of ischemia) was induced 24 hours before 60 minutes of ischemia. The adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) was administered intramuscularly immediately after ischemic preconditioning. Leukocyte behavior in the retina after 60 minutes of ischemia was evaluated in vivo with acridine orange digital fluorography. RESULTS: Ischemic preconditioning inhibited leukocyte rolling. The maximum number of rolling leukocytes was reduced to 3.0% at 12 hours after reperfusion (P < 0.01). Subsequent leukocyte accumulation was also decreased with ischemic preconditioning. The maximum number of accumulated leukocytes was reduced to 22.6% at 24 hours after reperfusion (P < 0.01). These inhibitory effects were suppressed by administration of DPCPX (P < 0.0001). The numbers of rolling leukocytes at 12 hours after reperfusion and accumulated leukocytes at 24 hours after reperfusion were 102.7% (NS) and 83.4% (P < 0.01), respectively, compared with the number without ischemic preconditioning. CONCLUSIONS: The present study demonstrates the inhibitory effects of ischemic preconditioning on leukocyte rolling and subsequent leukocyte accumulation during retinal ischemia-reperfusion injury. Furthermore, the adenosine A1 receptor may play an important role in these inhibitory effects.

Acridine Orange↗

PubMed2001

[A patient with intravascular malignant lymphomatosis presenting subacute dementia one year after sustained urinary retention and high serum LDH activity from the onset].

We report a 71-year-old man with intravascular malignant lymphomatosis who showed high serum LDH and urinary disturbance for one year before manifesting dementia. High serum LDH was found at a health check at age 70. Two months later, he had an onset of backache and urinary retention. MRI of the spinal cord was unremarkable. One year later, he showed decline of mental activities and was admitted to our hospital. He was agitated and confused. However cranial nerve palsy or limb weakness was not noted. The MRI of the brain showed T2-high signal in bilateral occipital, right temporal lobe and the left insular cortices. The abdominal CT scan showed swelling of the adrenals on both sides. Adrenal biopsy revealed diffuse large B cell lymphoma. He developed respiratory distress and he died two months after the admission. Post mortem examination revealed intravascular and extravascular proliferation of lymphoma cells in most of the internal organs including adrenals, spleen, liver and the kidneys. In the brain, the laminar necrosis was seen in the left occipital cortex and hemorrhagic infarctions were noted in the insular and temporal cortices and the medial temporal cortex. Sacral spinal cord showed necrosis of the gray matters and loss of myelinated fibers in the white matter. Intravascular proliferation of the lymphoma cells were also seen in the vessels of the brain and the spinal cord. This patient suggests the importance of survey for intravascular malignant lymphomatosis, when high serum LDH and myelopathy of lumbosacral area are seen.

Aged↗

PubMed2000

Investigation of possible involvement of several genes related to development of hepatocarcinogenesis in rats.

A comparative study on the possible involvement of several genes in the susceptibility of chemical carcinogenesis was carried out using carcinogen-resistant DRH rat and -sensitive Donryu and F344 rats. Previously, we observed that the induction of glutathione S-transferase placental form (GST-P) in the liver of Donryu rats by 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) was significantly greater than that of DRH rats. In the present study, we tentatively determined base sequences of the enhancer region including GPE-I and GPE-II (GST-P enhancers I and II) of GST-P genes of DRH, Donryu and F344 rats, but we did not observe any nucleotide polymorphism around these regions. Furthermore, the mRNA levels of silencer binding protein (NFA-1) for the GST-P promoter of rat liver were also similar in the DRH and Donryu rats. Since clonal expansion of putative preneoplastic GST-P-positive foci in the DRH rat liver was significantly suppressed during 3'-Me-DAB administration, we examined whether two opposite growth controlling factors, TGF-alpha and TGF-beta, may participate in such suppression of growth. It was supposed that mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R), at least in part, activates TGF-beta preproprotein. However, we observed that the levels of M6P/IGF2R mRNA in the livers of DRH were not higher than those of Donryu rats after being fed 3'-Me-DAB for 8 weeks. Another important factor in the carcinogenesis is insulin-like growth factor II itself. Although liver tumors induced by 3'-Me-DAB in F344 had high levels of IGF-II mRNA, little IGF-II gene expression existed in normal adult livers of Donryu, F344 and DRH rats. High levels of IGF-II mRNA were detected similarly in the livers of neonates from all these three strains of rats. Finally, we detected a significant increase of AFP (alpha-fetoprotein) mRNA in the livers of Donryu rats around 6 to 8 weeks from the start of 3'-Me-DAB feeding, which is in parallel with detrimental effects of this carcinogen on these rats. A reduced induction of AFP mRNA was observed in DRH rats under the same conditions. Further study will be needed to explain the lower tumor susceptibility in the DRH rat.

Animals↗

PubMed2000

A case of monoclonal gammopathy associated with acute myelomonocytic leukemia with eosinophilia suggested to be the result of lineage infidelity.

Acute myelomonocytic leukemia (AMMoL) accompanied by monoclonal gammopathy is a rare condition, and its pathogenesis and the cytogenetic mechanism of such leukemogenesis have not been determined in detail. A case of AMMoL with eosinophilia accompanied by immunoglobulin G kappa monoclonal gammopathy is described. Immunophenotypic studies of the peripheral blood and bone marrow mononuclear cells revealed no evidence of abnormally proliferating cells of B-lineage. DNA analyses of bone marrow mononuclear cells containing leukemic cells revealed rearrangement of the kappa-light chain (Igkappa) gene and c-myc and c-jun proto-oncogenes. The intensities of the rearranged bands for these genes on Southern blot analysis suggested the existence of a major population of leukemic cells with rearranged Igkappa gene and minor population(s) of leukemic cells with rearranged c-myc and/or c-jun proto-oncogene(s) in the patient's bone marrow and indicated the occurrence of genetic evolutionary changes in leukemic cells in this patient before starting chemotherapy. These results suggest that these leukemic cells are the most likely candidate for immunoglobulin G kappa monoclonal protein production, and structural abnormalities of c-myc and c-jun proto-oncogenes may have contributed to the evolution of leukemic cells in this patient.

Blotting, Southern↗

PubMed2000

Surgical treatment of a sigmoid volvulus associated with megacolon: report of a case.

Sigmoid volvulus occurring concomitantly with megacolon is an uncommon cause of bowel obstruction, and various approaches to treatment have been proposed. We report herein a case of sigmoid volvulus with megacolon that was successfully treated by elective surgery following endoscopic reduction during the same hospital stay. A 70-year-old woman was admitted to our hospital with abdominal pain, distension, and severe constipation. Physical examination, plain abdominal X-ray, and barium enema confirmed a sigmoid volvulus and further examinations revealed concomitant megacolon. An elective sigmoid colectomy was performed following successful endoscopic decompression. The postoperative course was uneventful and there was no residual colonic dysmotility. Histologically, no aganglionic tissue was observed in the resected specimen.

Abdominal Pain↗