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21.
Characterization of the clonality of non-Hodgkin's lymphoma (NHL) by the rearranged segments of immunoglobulin heavy chain (Ig(H)) or T cell receptor (TCR) genes is not only useful in the confirmation of the diagnosis but also for the future assessment of how a secondary lymphoma, such as a recurrence or another primary lymphoma, occurs. As a practical approach to obtaining and registering this information in a surgical pathology laboratory, FR3 and FR1 regions of Ig(H) gene and TCRgamma gene were concurrently amplified by polymerase chain reaction (PCR) using each pair of consensus primers and the same PCR protocol. Examined samples consisted of 134 primary NHL (phenotypically, 108 B cell and 26 T cell NHL), 19 reactive lymphadenopathies, as well as five secondary lymphomas whose primary lesions were included in this study. Among the primary NHL, the combined PCR analysis disclosed the clonality in 103 of 134 NHL (77%), by FR3 PCR in 77 B cell and two T cell NHL, by FR1 PCR in 59 B cell and one T cell NHL, and by TCRgamma PCR in 11 B cell and 17 of 26 T cell NHL, but in none of the reactive lymphadenopathies. Among the secondary lymphomas, the same pattern of PCR analysis was obtained in two cases (the durations between first and second lymphomas; 6 and 10 months), which suggested recurrence. In contrast, different results were obtained in three cases (17-37 months), which indicated another primary or emergence of the subclones. The results of Southern blot analysis were concordant with the PCR results of the first and the secondary lymphomas. Although the combined PCR analysis cannot replace Southern blot hybridization because of its lower detection rate, it can select those cases suitable for further Southern blot analysis thus reducing the number of unnecessary examinations by nearly 75%. This approach may also be useful in the comparative evaluation of primary and secondary lymphomas.  相似文献   
22.
Liver-infiltrating T cells play an essential role in the immunopathogenesis of autoimmune liver disease. Programmed death-1 (PD-1) and its ligands, B7-H1/PD-L1 and B7-DC/PD-L2, are new CD28-B7 family members that are involved in the regulation of immune responses. The ligation of PD-1 inhibits T-cell receptor-mediated T cell proliferation and cytokine production, and PD-1-deficient mice develop various organ-specific autoimmune diseases. To investigate the expressions of PD-1 and its ligands in autoimmune liver disease, in particular autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC), immunohistochemical analysis was performed. Liver biopsy specimens obtained from 17 patients with AIH and PBC were studied. PD-1 was expressed on more than half of the liver-infiltrating T cells within the portal tract. Some of the intrahepatic T cells expressed B7-H1 in patients with AIH and PBC. B7-H1 and B7-DC were mainly expressed on some Kupffer cells (KC) and liver sinusoidal endothelial cells (LSEC) within the sinusoids and their expression was upregulated in autoimmune liver disease. These results suggest that the interaction of PD-1 on T cells with increased expression of B7-H1 and B7-DC on KC and LSEC might be involved in the downregulation of autoreactive lymphocytes and result in the regulation of pathogenesis in autoimmune liver disease.  相似文献   
23.
In 2 infants with gastroenteritis associated with Norovirus (NoV), serum immunoglobulin (Ig) G, IgM, IgA, and fecal IgA antibody responses against NoV were examined by enzyme-linked immunosorbent assay using 11 different antigenic and genetic types of NoV virus-like particles expressed in insect cells. These two cases were putative primary single NoV infections, because antibodies against NoVs were not detected in acute-phase serums. In one of two cases, long-term excretion of virus RNA for 33 days was observed. Serum IgG responses demonstrated strong seroresponse to the homologous type, and weak seroresponse to the heterologous types within the genogroup. After more than 2 years, the IgG antibody titer remained high to the homologous type and low to the heterologous type within the genogroup. IgM and IgA were specific to the homologous type. IgM was short lived and the serum IgA antibody titer remained low to the homologous type for a long period. These results improve our understanding of the humoral immune response to NoV infection.  相似文献   
24.
25.
To clarify the participation of inducible NOS (iNOS) in the hypoxia-ischemia, we examined iNOS and its tetrahydrobiopterin co-factor in the cerebral cortex and plasma in a newborn-piglet model. We also investigated the role of hypothermia in iNOS expression and biopterin production. Male newborn piglets were ventilated 6% oxygen for 45 min. Their common carotid arteries were clamped during hypoxia. Then they were resuscitated with 30% oxygen (HI group). Piglets of the hypothermia group were treated as the HI group and their body was cooled to 35.5 degrees C after hypoxic-ischemic insults. Sham-treated piglets were also reserved. In the HI group, iNOS was present in neurons and macrophages of the cerebral cortex 12h after the insult. The concentrations of nitrite and nitrate were elevated in the cerebral cortex 12h after hypoxic-ischemic insults but the biopterin level was unchanged. The plasma biopterin concentration after the insult (377.9+/-78.7 nM) was five times higher than before the insult (80.1+/-4.3 nM); this level peaked 4h after the insult (604.8+/-200.9 nM) and only slightly decreased after 12h (445.9+/-57.8 nM). In the hypothermia group, no iNOS expression was observed 12h after the insult. The plasma biopterin concentration after the insult (464.2+/-92.3 nM) was similar to that in the HI group, but was suppressed by 4h of hypothermia (229.3+/-106.8 nM). In this study, neuronal iNOS expression and increase of NO production were found in the acute phase of hypoxia-ischemia. Brain biopterin did not increase in hypoxia-ischemia although plasma biopterin was five-fold elevated. The discrepancy may also affect hypoxic-ischemic organ damage.  相似文献   
26.
Laparoscopic surgery has had a remarkable impact on the practice of colorectal surgery. However, most operations are performed using a technique of laparoscopic assistance, whereby extracorporeal bowel division and anastomosis are made following laparoscopic mobilization of the bowel. To our knowledge, this is the first report to describe a case of chronic constipation managed by total colectomy with ileorectal anastomosis, performed completely laparoscopically. The diagnosis of slow transit constipation was made by a transit time study. After dissection of the entire colon, the colon to be resected was delivered through the open rectal stump and brought out transanally. The anvil of an intraluminal circular stapler was passed through the rectum into the peritoneal cavity and the end of the open distal rectum was closed with a linear cutting stapler. The anvil of the circular stapler was inserted into the end of the open terminal ileum and fixed with an Endo-Loop, following which an intracorporeal double-stapling anastomosis was performed. By 3 months following surgery, the patient was passing 3–4 stools a day. Thus, we highly recommend this technique as it eliminates the need for a small incision to deliver the resected colon, thereby minimizing the operative time and risk of wound infection. Received: August 23, 2001 / Accepted: January 8, 2002  相似文献   
27.
BACKGROUND: Adenoma malignum is a rare variant of uterine cervical adenocarcinoma. In this report, we present an extremely rare case of adenoma malignum with large cystic lesions (diameter of more than 10 cm) which elicited urinary obstruction. CASE: A 46-year-old Japanese woman, gravida 2, para 2, visited her local doctor for urinary obstruction, and 950 ml of urine was catheterized. Since abdominal ultrasonography suggested ovarian cystic tumor, she was referred to our hospital. Vaginal examination and ultrasonography revealed a child-head-sized multilocular cystic tumor in the Douglas pouch. Abnormal massive discharge was not observed at the time of admission. During preoperative examination, massive mucinous discharge suddenly occurred without pain. The cystic tumor size shrank from x10 cm to x4.0 cm in maximum diameter. Emergent abdominal hysterectomy was performed. The operative findings revealed collapsed cystic lesions in the posterior wall of the uterine cervix. Microscopically, the multiple cysts in the cervix were composed of high columnar and slightly atypical monolayer cells similar to endocervical mucinous cells. Vaginal invasion was also partly observed. Most of the tumor cells were positive for carcinoembryonic antigen and HIK1083 in their cytoplasm, and scattered chromogranin A-positive endocrine cells were also found in tumor glands, corresponding to minimal deviation adenocarcinoma (adenoma malignum). These lesions were diagnosed as FIGO stage IIa. The patient is disease-free 2 years after primary surgery. CONCLUSION: In the present report, we describe an extremely rare case of adenoma malignum with large cystic lesions reaching a diameter of 12 cm which resulted in urinary obstruction.  相似文献   
28.
This study was designed to elucidate the mechanisms of cisplatin (CDDP) resistance using two human ovarian cancer cell lines, KF and TYK, and two CDDP-resistant lines, KFr and TYK/R, derived from the former lines. KFr and TYK/R showed about 3-fold higher resistance to the cytotoxic effects of CDDP than their parental lines. They also showed a significant increase in sensitivity to not only etoposide, but also (+)-(4S)-4, ll-diethyl-4-hydroxy-9-[(4-piperidino-piperidino)carbonyloxy]-l H -pyrano[3',4':6,7]inodolizino[l,2- b ]quinoline-3,14(4 H , 12 H )-dione hydrochloride trihydrate (CPT-11). Cellular CDDP accumulation levels in KFr and TYK/R were decreased from those of the parental cells. By contrast, the cellular glutathione (GSH) content in KFr cells was 1.7-fold higher than that in KF, whereas TYK/R cells had a 40% lower content than TYK cells. Cellular mRNA levels of drug-resistance-related genes, such as DNA topoisomerase (topo) I and topo II, glutathione S-transferase-π (GST-π;), γ-glutamylcysteine synthetase (.γ -GCS ), and metallothionein ( hMT ) genes, were compared between drug-sensitive KF or TYK and KFr or TYK/R. KFr cells had 8.5- and 24.7-fold higher mRNA levels of γ-GCS and topo II genes than KF cells while KFr had only a slight increase in GST-π mRNA level as compared with KF. By contrast, TYK/R cells had 2.9- and 1.7-fold higher hMT and topo I mRNA levels than TYK cells. Acquisition of CDDP resistance in human ovarian cancer cells thus appeared to be related mainly to expression of γ -GCS, topo II and hMT genes, and partly to that of topo I and GST-π genes, in addition to a decrease in CDDP accumulation  相似文献   
29.
Tetrahydrobiopterin (BH4)-responsive phenylalanine hydroxylase (PAH) deficiency is characterized by reduction of blood phenylalanine level after a BH4-loading test. Most cases of BH4-responsive PAH deficiency include mild phenylketonuria (PKU) or mild hyperphenylalaninemia (HPA), but not all patients with mild PKU respond to BH4. We performed the phenylalanine breath test as reliable method to determine the BH4 responsiveness. Phenylalanine breath test quantitatively measures the conversion of L-[1-13C] phenylalanine to 13CO2 and is a noninvasive and rapid test. Twenty Japanese patients with HPA were examined with a dose of 10 mg/kg of 13C-phenylalanine with or without a dose of 10 mg . kg(-1) . d(-1) of BH4 for 3 d. The phenylalanine breath test [cumulative recovery rate (CRR)] could distinguish control subjects (15.4 +/- 1.5%); heterozygotes (10.3 +/- 1.0%); and mild HPA (2.74%), mild PKU (1.13 +/- 0.14%), and classical PKU patients (0.29 +/- 0.14%). The genotypes in mild PKU cases were compound heterozygotes with mild (L52S, R241C, R408Q) and severe mutations, whereas a mild HPA case was homozygote of R241C. CRR correlated inversely with pretreatment phenylalanine levels, indicating the gene dosage effects on PKU. BH4 loading increased CRR from 1.13 +/- 0.14 to 2.95 +/- 1.14% (2.6-fold) in mild PKU and from 2.74 to 7.22% (2.6-fold) in mild HPA. A CRR of 5 to 6% reflected maintenance of appropriate serum phenylalanine level. The phenylalanine breath test is useful for the diagnosis of BH4-responsive PAH deficiency and determination of the optimal dosage of BH4 without increasing blood phenylalanine level.  相似文献   
30.
In September 2003, a new revision of the draft guideline (Organization for Economic Co-operation and Development [OECD] Guideline for the Testing of Chemicals, Proposal for a New Guideline 426, Developmental Neurotoxicity Study) was distributed. The draft guideline consists of 51 paragraphs and an appendix. The National Coordinators were requested to arrange national expert reviews of the guideline proposal in their member countries. The member of the Behavioral Teratology (BT) Committee of the Japanese Teratology Society (JTS) reviewed, discussed and commented on the draft Test Guideline proposal. The BT Committee of the JTS also commented that the International Collaborative Study to validate this protocol should be definitely performed. These comments were sent to the OECD Secretariat. The BT Committee of the JTS expects that the comments are useful for further discussion.  相似文献   
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