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T Kitada

Publications and source records attributed to T Kitada.

At least 37 records · Page 2Linked to original sources

Overexpression of alpha1-6 fucosyltransferase in hepatoma cells suppresses intrahepatic metastasis after splenic injection in athymic mice.

Changes in oligosaccharide structures alter the biological functions of cancer cells. Alpha1-6 fucosyltransferase (alpha1-6FucT) catalyzes the transfer of fucose to the innermost GlcNAc in N-glycans. Although alpha1-6FucT is barely detected in normal liver, it is enhanced during rat hepatocarcinogenesis and in human hepatoma. To understand the biological meaning of the alpha1-6FucT in hepatoma, especially in terms of metastasis, we established human hepatoma cell lines, which express high levels of alpha1-6FucT by transfection of the alpha1-6FucT gene and investigated intrahepatic metastasis after splenic injection to athymic mice. Tumor formation in the liver was dramatically suppressed in the alpha1-6FucT transfectants (1 of 9 and 1 of 10 in alpha1-6FucT transfectants versus 6 of 9 and 6 of 9 in controls). Although there were no differences in terms of cell invasiveness to a Matrigel or in terms of cytotoxicity to interleukin 2-treated lymphocytes between alpha1-6FucT transfectants and control cells, cell adhesion to mice hepatocytes and nonparenchymal liver cells in culture was significantly inhibited in alpha1-6FucT transfectants, compared to the controls. Attachment of alpha1-6FucT transfectants to a fibronectin-coated dish was decreased compared to controls because alpha5beta1 integrin was more strongly alpha1-6 fucosylated in the alpha1-6FucT transfectants. Two-dimensional electrophoresis followed by lectin blot showed that certain glycoproteins (Mr 50,000-150,000, pI 4.8-5.5) were alpha1-6 fucosylated and might be linked to suppression of intrahepatic metastasis. This is the first demonstration of the biological significance of alpha1-6 fucosylation on N-glycans in hepatoma cells under in vivo conditions.

Animals↗

Polymorphism in the parkin gene in sporadic Parkinson's disease.

We report polymorphism of the parkin gene in 160 sporadic Parkinson's disease (PD) patients and controls. Three polymorphisms were found: a G-to-A transition in exon 4 (S/N167), a C-to-T transition in exon 10 (R/W366), and a G-to-C transition in exon 10 (V/L380). Genotype distributions and allele frequencies of S/N167 and V/L380 did not differ significantly between the two groups. The R/W366 allele frequency was significantly lower in PD patients (1.2 vs 4.4%). The level of protection from PD provided by this allele was 3.60 (95% CI; range, 0.45-6.50), suggesting that it may be a protective factor against PD.

Aged↗

Immunohistochemical and subcellular localization of Parkin protein: absence of protein in autosomal recessive juvenile parkinsonism patients.

Autosomal recessive juvenile parkinsonism (AR-JP) is a distinct clinical entity characterized by a selective degeneration of nigral neurons. Recently, the parkin gene responsible for AR-JP has been identified. Now, we report the subcellular localization of Parkin protein in patients with AR-JP or Parkinson's disease (PD) and in controls by immunoblotting and immunohistochemistry using antibodies raised against the Parkin molecule. Parkin protein was absent in all regions of the brains of patients with AR-JP. Parkin protein was not decreased in the brains of sporadic PD patients. Immunoreactivity was detected in a few Lewy bodies. Parkin protein was located in both the Golgi complex and cytosol.

Brain↗

Neuroendocrine carcinoma of the sigmoid colon: report of a case.

Neuroendocrine carcinoma of the colon is a rare entity; however, this type of tumor is known for its aggressive progression and poor prognosis. A case of a 56-year-old Japanese male is presented in this report. A huge, child's head-sized tumor was found to have grown extraluminally on the sigmoid colon with multiple liver metastases. The tumor measured 16.5 x 15 x 8.2 cm in size and weighed 1 300 g. The patient died of hepatic failure due to massive liver metastases 6 months after operation. The pathological findings including an electron microscopic analysis were correlated with those of neuroendocrine carcinoma. We reviewed the English literature, and analyzed 94 cases of neuroendocrine carcinoma which had been reported previously. The nomenclature and definition of this disease still remains somewhat unclear, and not a small population of this disease may thus have been misdiagnosed and treated as other less aggressive entities. The necessity to make an accurate differential diagnosis in such cases is thus emphasized.

Carcinoma, Neuroendocrine↗

Significant role of apoptosis in type-1 autoimmune hepatitis.

We used the terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate-digoxigenin nick-end labeling (TUNEL) method to detect apoptosis, and immunohistochemical staining for molecules related to apoptosis, a marker of cell proliferation, and surface markers of lymphocytes to examine 20 patients with autoimmune hepatitis (AIH). Confluent hepatic necrosis was frequently found, in which rosette formation of hepatocytes and ductular proliferation were common. TUNEL staining and staining for Lewis Y antigen, Bax protein, and Fas antigen were found in biliary epithelial cells in bile ducts and proliferating atypical bile ductules in regions of confluent necrosis with severe lymphocytic infiltration. TUNEL staining and staining for Lewis Y antigen and Bax protein were found in rosette-forming hepatocytes. Many hepatocytes in lobules without injury were stained for proliferating cell nuclear antigen (PCNA). bcl-2 oncoprotein was found in many lymphocytes surrounding proliferating atypical bile ductules and rosette-forming hepatocytes in regions of confluent necrosis, in which CD20 and OPD 4 were found. Apoptosis of both hepatocytes in rosette arrangement and biliary epithelial cells in bile ducts and proliferating atypical bile ductules may play a role in progression of AIH as well as confluent hepatic necrosis.

Adult↗

Point mutations (Thr240Arg and Gln311Stop) [correction of Thr240Arg and Ala311Stop] in the Parkin gene.

Autosomal recessive juvenile parkinsonism (AR-JP) is a distinct clinical and genetic entity characterized by selective degeneration of nigral neurons. Recently, the parkin gene responsible for AR-JP has been identified. To date, we found two different deletional mutations including single and multiple exonic deletions. In the present study, we identified two types of point mutations (Thr240Arg and Gln311Stop) involving exons 6 and 8 in the parkin gene of the AR-JP patients from two Turkish families. This is the first report on point mutations for the parkin gene. Furthermore, the Thr240Arg mutation was located on a consensus sequence for the site of phosphorylation by casein kinase II. Identification of its mutation provides an important clue as to the role of the Parkin protein in degeneration of the substantia nigra in the brain of AR-JP patients.

Adolescent↗

Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism.

Parkinson's disease is a common neurodegenerative disease with complex clinical features. Autosomal recessive juvenile parkinsonism (AR-JP) maps to the long arm of chromosome 6 (6q25.2-q27) and is linked strongly to the markers D6S305 and D6S253; the former is deleted in one Japanese AR-JP patient. By positional cloning within this microdeletion, we have now isolated a complementary DNA done of 2,960 base pairs with a 1,395-base-pair open reading frame, encoding a protein of 465 amino acids with moderate similarity to ubiquitin at the amino terminus and a RING-finger motif at the carboxy terminus. The gene spans more than 500 kilobases and has 12 exons, five of which (exons 3-7) are deleted in the patient. Four other AR-JP patients from three unrelated families have a deletion affecting exon 4 alone. A 4.5-kilobase transcript that is expressed in many human tissues but is abundant in the brain, including the substantia nigra, is shorter in brain tissue from one of the groups of exon-4-deleted patients. Mutations in the newly identified gene appear to be responsible for the pathogenesis of AR-JP, and we have therefore named the protein product 'Parkin'.

Adult↗

A microdeletion of D6S305 in a family of autosomal recessive juvenile parkinsonism (PARK2).

A gene for autosomal recessive juvenile parkinsonism (ARJP; HGMW-approved symbol PARK2; MIM 600116) has recently been mapped to a 17-cM interval on chromosome 6q25.2-q27. We here report an inbred family with ARJP showing a perfect cosegregation with null allele for D6S305, which is a marker within the ARJP locus. We assigned the deletion within an interval between D6S1937 and AFMa155td9, which are 0 cM apart from each other and located on a single YAC clone. Two possibilities should be evaluated: (1) the deletion is polymorphic and linked to ARJP and (2) the deletion is pathogenic and contains both D6S305 and the ARJP gene (or a part of it). An exon search in a deleted segment or in the relatively small-sized genomic clones harboring D6S305 may enormously facilitate the cloning procedure of the ARJP gene.

Chromosome Deletion↗

Molecular genetic analysis of a novel Parkin gene in Japanese families with autosomal recessive juvenile parkinsonism: evidence for variable homozygous deletions in the Parkin gene in affected individuals.

Autosomal recessive juvenile parkinsonism (AR-JP) is a distinct clinical and genetic entity characterized by selective degeneration of nigral dopaminergic neurons and young-onset parkinsonism with remarkable response to levodopa. Recently, we mapped the gene locus for AR-JP to chromosome 6q25.2-q27 by linkage analysis and we identified a novel large gene, Parkin, consisting of 12 exons from this region; mutations of this gene were found to be the cause of AR-JP in two families. Now we report results of extensive molecular analysis on 34 affected individuals from 18 unrelated families with AR-JP. We found four different homozygous intragenic deletional mutations, involving exons 3 to 4, exon 3, exon 4, and exon 5 in 10 families (17 affected individuals). In addition to the exonic deletions, we identified a novel one-base deletion involving exon 5 in two families (2 affected individuals). All mutations so far found were deletional types in which large exonic deletion accounted for 50% (17 of 34) and the one-base deletion accounted for 6% (2/34); in the remaining, no homozygous mutations were found in the coding regions. Our findings indicate that loss of function of the Parkin protein results in the clinical phenotype of AR-JP and that subregions between introns 2 and 5 of the Parkin gene are mutational hot spots.

Amino Acid Sequence↗

Granular cell tumor of the duodenum: a case report.

Granular cell tumor (GCT) in the duodenum is an extremely rare disease: only one case has been listed in a review, to date. We reported a 47-yr-old Japanese male case with GCT of the duodenum. Clinically, melena caused by bleeding from the tumor was the only symptom. The tumor cells showed abundant, granular eosinophilic cytoplasm. Although this tumor was clinically and histologically benign, highly developed tumor microvessels were demonstrated both angiographically and histologically, suggesting malignant potential of the tumor.

Duodenal Neoplasms↗

Induction of apoptosis in a human hepatocellular carcinoma cell line by a neutralizing antibody to transforming growth factor-alpha.

A cell line derived from a Japanese man with hepatocellular carcinoma was established in culture and designated OCUH-16. The cell line has the morphological and chromosomal features of hepatocellular carcinoma cells and has a short doubling time (approximately 33 h). OCUH-16 cells were shown to express transforming growth factor-alpha (TGF-alpha) in addition to albumin, DNA polymerase-alpha, c-JUN, and the retinoblastoma gene product. Electron microscopy revealed TGF-alpha immunoreactivity associated with the cell membrane, but TGF-alpha was not detected in medium conditioned by OCUH-16 cells by enzyme-linked immunosorbent assay. Reverse transcription and polymerase chain reaction analysis revealed the presence of TGF-alpha messenger RNA in these cells. Culture of OCUH-16 cells in the presence of a neutralizing antibody to TGF-alpha inhibited cell proliferation and induced many cells to undergo apoptosis (programmed cell death). These observations suggest that endogenous TGF-alpha is necessary for OCUH-16 cell growth.

Antibodies, Monoclonal↗

Hepatic expression of c-Myb in chronic human liver disease.

C-Myb is a sequence-specific DNA binding protein that regulates the expression of genes involved in cell proliferation and differentiation. The present study was designed to elucidate the role of c-Myb in the pathogenesis of chronic liver disease by an immunohistochemical approach. In normal (control) livers, few or no hepatic cells were positive for c-Myb. In livers from patients with chronic viral hepatitis, positive staining for c-Myb was found not only in spindle-shaped mesenchymal cells in expanded portal areas, but also in perisinusoidal cells (PSCs) within liver lobules. In cirrhotic livers, a few PSCs within lobules were positive for c-Myb, while no staining was seen in fibrous septa. Immunoelectron microscopy revealed that c-Myb-positive PSCs displayed morphological features of hepatic stellate cells. Other sinusoidal lining cells including Kupffer cells and sinusoidal endothelial cells, as well as hepatocytes, were all negative for c-Myb. Dual c-Myb/alpha-smooth muscle actin (alphaSMA) staining revealed that more than 97% of c-Myb-positive cells were alphaSMA-positive. Moreover, dual c-Myb/proliferating cell nuclear antigen (PCNA) staining showed that approximately 70% of c-Myb-positive cells also expressed PCNA. The labeling index (LI) (number of c-Myb-positive cells/0.1 mm2) significantly correlated with serum transaminase concentrations and increased in parallel with the disease activity. However, the LI showed no correlation with the degree of fibrosis. These results suggest that c-Myb may be involved in stellate cell activation and proliferation in chronically diseased human livers, and that the level of c-Myb expression is associated with the activity of chronic hepatitis.

Actins↗

Expression of antigens related to apoptosis and cell proliferation in chronic nonsuppurative destructive cholangitis in primary biliary cirrhosis.

The initial injury in primary biliary cirrhosis (PBC) is the destruction of portal bile ducts. Little information is available on apoptosis and cell proliferation in such bile ducts, so we used immunohistochemical techniques to locate molecules related to apoptosis [Fas antigen, Lewis Y antigen (BM1/JIMRO), and bcl-2 protein] and to cell proliferation (proliferating cell nuclear antigen, PCNA) in 21 patients with PBC. In addition, nick-end labelling was done to locate DNA fragmentation. The expression of these molecules in chronic nonsuppurative destructive cholangitis (CNSDC) was examined. Cell death and PCNA expression were both found in portal bile ducts affected by CNSDC in 7 of the 13 CNSDC patients examined. Fas antigen was found on the plasma membrane and rough endoplasmic reticulum of bile-duct cells with CNSDC in the frozen sections of all 6 patients with CNSDC out of the 9 patients inspected, and this antigen was found also in bile-duct cells without CNSDC in 2 of these 9 patients. It was not found in anatomically normal liver (from 2 patients with Gilbert's disease). The Lewis Y antigen was found in bile ducts with CNSDC and in proliferated ductules in all 16 patients examined. No bcl-2 protein was found in any bile-duct or ductule cells, but it was found in the cytoplasm of lymphocytes surrounding or invading CNSDC. DNA fragmentation was found in the nuclei of bile-duct cells with CNSDC by nick-end labelling. Our study indicated that Fas-mediated apoptosis might be involved in CNSDC, but that bcl-2 protein seems to participate less than Fas. Although the Lewis Y antigen was found in many bile ducts, the relationship between the antigen and apoptosis remains unknown because there was no evidence that this antigen mediates apoptosis.

Adult↗

[A 34-year-old woman with delayed motor milestones, high arched palate, and proximal muscle weakness].

We report a right-handed 34-year-old woman with diffuse muscle atrophy. The patient was a full-term infant of uneventful delivery, however, motor milestones were delayed in that neck control was obtained at 10 months of the age and she started to walk unassisted at 2 years of the age. Mental development was normal. She was unable to run with her mates at her kindergarten and she required a handrail when she walk up the stairs. She could not close her mouth completely at the primary school. She was unable to use a straw as a middle school pupil. Recently, she noted difficulty in raising her head from the supine position, and has become unable to walk a long distance. She was admitted to our hospital in September 17, 1994 when she was 34-year-old. On admission, general physical examination revealed that she looked slender weighing 38 kg with 149.5 cm height. She showed a high arched palate, slight scoliosis, and pes equinus. Otherwise general physical examination was unremarkable. Upon neurologic examination, she was alert and well oriented. Cranial nerves were unremarkable except for bilateral facial atrophy and moderate weakness. Her voice was of nasal quality, and swallowing was slightly difficult. No atrophy was noted in the sternocleidomastoid muscle. She showed waddling gait and positive Gowers' sign. Diffuse muscle atrophy was noted and mild to moderate weakness was presented more in the proximal part in both upper and lower extremities, however, deltoid muscles retained normal power. No ataxia was noted. All the deep tendon reflexes were lost. Sensation was intact. Routine laboratory examination was unremarkable. Serum CK was 56 IU/l. Electromyography revealed myogenic changes in the deltoid, biceps, and quadriceps muscles. A diagnostic biopsy was performed in the left biceps brachii muscle. The patient was discussed in the neurologic CPC, and the chief discussant arrived at the conclusion that the patient had nemaline myopathy. Opinions were divided among nemaline myopathy, central core disease, and congenital fiber type disproportion. Histologic examination of the biopsied specimen revealed marked atrophy of type 1 muscle fibers; many central nuclei were seen in the type 1 fibers. Approximately 70% of the muscle fibers were type 1 fibers. No nemaline rods or central cores were noted. Histologic appearance was consistent with the diagnosis of congenital fiber type disproportion.

Adult↗

[A 56-year-old man with fever, backache and tetraparesis].

We report a 56-year-old man who developed progressive paraparesis. He was apparently well, except for left Bell's palsy which developed on May 9 of 1994, for which he received stellate ganglion block on the left side more than ten times until July 2nd of 1994, when he noted pain in his left shoulder and in his lumbar region. On July 5th, he noted some difficulty in urination. On July 6th, he noted tingling sensation in his four extremities and difficulty in gait. He was admitted to another hospital where he was treated with intravenous infusion of glycerol. After this treatment, his gait and sensory disturbance showed some improvement, however, on July 7th, his shoulder and lumbar pain worsened, and he became unable to stand. His temperature went up to 39 degrees C on the next day. Lumbar CSF on that day contained 119 cells/microliters, 112 mg/dl of protein, and 53 mg/dl of sugar. He was transferred to our hospital on July 14th. His past medical history revealed that he had suffered from frequent bouts of osteomyelitis since the age of 13 years. He was operated on several times on osteomyelitis. He had been treated on his tooth ache until shortly before the onset of the present illness. He also received steroid hormone for his Bell's palsy. On admission, his consciousness varied from alert to stupor. His BP was 150/100 mmHg, HR 98/min and regular, BT 39.4 degrees C. The bulbar conjunctiva appeared somewhat icteric. Otherwise, general physical examination was unremarkable. On neurologic examination, there was no apparent dementia. Higher cerebral functions appeared intact. The optic discs were flat. Pupils were round and isocoric reacting to light and accommodation promptly. Ocular movements were full without nystagmus. Some exophthalmos was noted bilaterally. The sensation of the face and facial muscles were intact. The remaining cranial nerves also appeared intact. Nuchal rigidity was present. He was unable to stand or walk. Muscle strength was markedly diminished in all four limbs; manual muscle testing revealed 1 to 2/5 weakness in both upper and lower extremities bilaterally. Muscle stretch reflexes were decreased or lost in both upper and lower limbs, but the plantar response was extensor on the right. Sensation appeared to be diminished in legs, but detail was not clear because of disturbance of consciousness. Pertinent laboratory findings were as follows: WBC 12,800/microliter, GPT 58 IU/l, total bilirubin 2.65 mg/dl, and CRP 16.8 mg/dl. Cerebrospinal fluid contained 34 cells/microliter (approximately two thirds were neutrophils), RBC 1,110/microliter, 2,949 mg/dl of protein, and 119 mg/dl of glucose; stapylococcus aureus was cultured from the CSF. Myelogram showed a filling defect in the anterior epidural space between the low thoracic and the upper lumbar region. The patient was treated with cephotaxim, aminobenzyl penicillin, and chloramphenicol. On the second hospital day, his BT was still 39 degrees C and he was agitated His weakness was worse than the previous day. Spinal MRI was attempted; as he was agitated 5 mg of diazepam was given intravenously at 4 PM. His respiration was rapid and somewhat shallow. At 6 PM, gadolinium DTPA was injected intravenously; at that time, he was breathing and pupils were 3 mm on both sides. At 6:35 PM, an examiner noted that he stopped breathing; the left pupil was dilated to 5 mm. Cardiopulmonary resuscitation was initiated immediately, and intubation was performed. He was placed on a respirator. His blood pressure did not reach 100 mmHg; he was in deep coma. Cardiac arrest occurred at 8:53 AM on the next morning. The patient was discussed in a neurological CPC. Most of the participants thought that the patient had either spinal epidural empyema or spinal subdural abscess. The question was what might be the original focus of infection. Three possibilities were considered, i.e., stellate ganglion block, teeth infection, and osteomyelitis...

Back Pain↗

Telomere shortening in chronic liver diseases.

We measured the telomere length in patients with chronic hepatitis or liver cirrhosis and found a significant telomere shortening in the liver with chronic liver disease compared to that in the normal liver. The telomere length tended to decrease with the progression of chronic liver disease.

Adult↗

Expression of the retinoblastoma gene product in human hepatocellular carcinoma.

Using the mouse anti-human retinoblastoma gene product (pRB) monoclonal antibody, PMG3-245, pRB was detected immunohistocytochemically in human hepatocellular carcinoma (HCC) tissues and a human HCC cell line, designated OCUH-16, recently established in our laboratory. This antibody reacted with human pRB and yielded a single band of approximately 110 kd from cultured OCUH-16 cells. The granules that stained for pRB were found mostly in the HCC cell nuclei, with a few granules observed in the rough endoplasmic reticulum by electron microscopy. Most of the stained granules were located in the euchromatin-rich areas. The percentage of OCUH-16 cells that expressed pRB or DNA polymerase alpha (DNA-PA) decreased over time as the number of OCUH-16 cells increased. The number of HCC cells that stained for pRB in the biopsy specimens from 11 patients varied and pRB expression was well maintained in early and advanced HCC. The level of pRB expression did not correlate with the differentiation of HCC cells or the clinical prognosis. The expression of pRB statistically correlated with that of DNA-PA (P < .01; r = .92). Some sinusoidal cells also stained for pRB. These findings imply that large deletions in the pRB gene are rare in the initiation or promotion of HCC. The correlation between pRB and DNA-PA may suggest that stained pRB participates in the proliferation of both HCC and non-HCC cells.

Adult↗

Immunohistochemical analysis of retinoblastoma gene product (pRB) expression in malignant and non-malignant liver diseases.

The retinoblastoma gene product is a nuclear phosphoprotein that undergoes cell cycle-dependent changes in its phosphorylation status. To analyze the expression of retinoblastoma gene product in the process of liver regeneration and the initiation of hepatocellular carcinoma, we studied immunohistochemically the expression of retinoblastoma gene product and DNA polymerase alpha (DPA) in 33 patients with various liver diseases. Only a few hepatocytes positive for retinoblastoma gene product were found in undamaged, nonregenerating liver tissues, whereas many hepatocytes positive for retinoblastoma gene product were detected in specimens of regenerating liver obtained from patients with acute or chronic liver diseases. Similarities were found between distribution patterns of hepatocytes positive for retinoblastoma gene product and those of hepatocytes positive for DPA, and a highly significant positive correlation was found between the number of hepatocyte nuclei stained for retinoblastoma gene product per 1000 nuclei examined (R-LI) and the number of hepatocyte nuclei stained for DPA per 1000 nuclei examined (D-LI) in tissues obtained from patients with nonmalignant liver disease. Hepatocellular carcinoma cells positive for DPA were detected in the 14 hepatocellular carcinoma specimens tested. In ten of these specimens, hepatocellular carcinoma cells positive for retinoblastoma gene product were found but not in the other four. For all hepatocellular carcinoma specimens, R-LI was proportional to D-LI. Thus in both nonmalignant and malignant liver, retinoblastoma gene product increased in proportion to proliferation of hepatocytes or hepatocellular carcinoma cells.

Adult↗