Crystal structures of nucleic acid complexes of ribonuclease U2

Crystal structures of adenine-specific Ustilago sphaerogena ribonuclease U2 complexed with the substrate analogues, d(ApG), d(ApGpG), and d(ApGpC), with the intermediate analogue, 2',3'-O-isopropylidene-adenosine, and with the product, 3'-AMP, have been determined. In each structure, the adenine base is recognized by the enzyme with four hydrogen-bonds. In the substrate analogue structures, the second base of guanine is sandwiched between His 101 and Tyr 107 side-chains, and forms two hydrogen-bonds with Tyr 107 O and Asp 108 O delta 1 atoms. The third base of the trinucleotides is in van der Waals interaction with the Tyr 78 side-chain. The phosphate group between the second and third nucleosides forms two hydrogen-bonds with the side chains of Asp 37 and Tyr 78. Oxygen atoms of the scissile phosphate group are involved in interactions with catalytic residues of Tyr 39, His 41, Glu 62, Arg 85, and His 101. These interactions indicate that either His 41 or Glu 62 acts as a general base and His 101 acts as a general acid in the first step of RNA hydrolysis.

The cbaAB genes for bo3-type cytochrome c oxidase in Bacillus stearothermophilus

Structural genes were cloned for cytochrome bo3-type cytochrome c oxidase recently isolated from a Gram-positive thermophile Bacillus stearothermophilus. Sequencing and Northern blotting analyses indicated that the two genes cbaA and cbaB composed an operon encoding for subunits I and II, respectively, and that the oxidase was SoxB-type. They are the first genes for a SoxB-type cytochrome c oxidase whose natural substrate is known.

Succinimide and isoaspartate residues in the crystal structures of hen egg-white lysozyme complexed with tri-N-acetylchitotriose

The isomerization of Asp101 to isoaspartate autocatalytically proceeds via a succinimide intermediate in hen egg-white lysozyme at a mildly acidic condition. The crystal structures of succinimide and isoaspartate forms of the lysozyme proteins, each complexed with a tri-N-acetylchitotriose ligand, have been determined at 1.8 A resolution, and distinctively elucidate coplanar cyclic aminosuccinyl and beta-linked isoaspartyl residues. Compared with the liganded native protein with normal Asp101, succinimide 101 protrudes toward the ligand, and isoaspartate 101 extends away from the ligand. The formations of these residues caused the loss of three hydrogen-bonds between the ligand and the side-chains of Asp101 and Asn103 along with 0.5 A displacement of the ligand location.

Two cases of adult varicella accompanied by hepatic dysfunction

Varicella is a typical acute exanthematous viral infection caused by varicella-zoster virus (VZV). In recently years, as far as hepatic dysfunction caused by viruses other than the hepatitis virus is concerned, there have been a few reports on hepatic dysfunction accompanying varicella following organ transplantation of Europe and America and another report on an immunocompromized adult following treatment for Systemic lupus erythematosis (SLE) in Japan. Nonetheless, we searched the MEDLINE and J MEDICINE listing the publications between 1986 and 1996 and found one report on healthy adults with varicella accompanied by hepatic dysfunction in Europe and America and two reports in Japan. Only Noguchi et al. dealt with the findings of liver biopsy. We examined two healthy adults with varicella and mild-to-moderate hepatic dysfunction, and referred to the results of their liver biopsies. The present paper discusses this issue, citing some references.

Cytotoxic actions of FTY720, a novel immunosuppressant, on thymocytes and brain neurons dissociated from the rat

Effects of FTY720 (2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol HCl), a novel immunosuppressant, were examined on neurons and thymocytes respectively dissociated from rat brains and thymus glands using a flow cytometer to see if FTY720 exerts cytotoxic actions not only on spleen cells as previously reported but also on the other cells. FTY720 at a concentration of 10 microM deteriorated almost all of the thymocytes, while it was not the case for brain neurons. FTY720 increased the intracellular concentration of Ca2+ ([Ca2+]i) of thymocytes in both the presence and absence of external Ca2+, although the [Ca2+]i increased by FTY720 in the presence of external Ca2+ was much greater than that in the absence of external Ca2+. Thus, FTY720 may increase the membrane permeability of Ca2+ and release Ca2+ from intracellular Ca2+ stores in thymocytes. Furthermore, the number of thymocytes stained with ethidium, a dye impermeant to intact membranes, time-dependently increased after drug application. Therefore, FTY720 at concentrations of 3 - 10 microM non-specifically increases the membrane permeability of thymocytes, resulting in necrotic cell death, although FTY720 at micromolar concentrations was reported to induce apoptosis of spleen cells.

Sero-epidemiologic study of hepatitis C virus infection in Fukuoka, Japan

We conducted an epidemiological study of 509 residents of H town, Fukuoka, Japan, to investigate the high mortality rate from liver disease. Antibodies to hepatitis C virus (HCV) (anti-HCV) were detected in 120 residents (23.6%); HCV RNA in 91 (17.9%), and hepatitis B surface antigen (HBsAg) in 13 (2.6%). Multivariate logistic regression analyses showed that presence of anti-HCV, male gender, and history of liver disease were associated with the presence of liver dysfunction, and that age of more than 40 years and a particular district were associated with the presence of anti-HCV. HCV RNA was more frequently detected in anti-HCV-positive men than women (41, or 85.4% versus 50, or 69.4%) (P < 0.05). The incidence of liver dysfunction was significantly higher in HCV RNA-positive men than women (32, or 66.7% versus 22, or 30.6%) (P < 0.05). These findings suggest that: (1) HCV was correlated with the high mortality rate from liver diseases, (2) there were district-related differences in the incidence of HCV, and (3) the lower frequency of elimination of HCV from men may explain why they showed a high mortality from liver disease.

From dystrophinopathy to sarcoglycanopathy: evolution of a concept of muscular dystrophy

Duchenne and Becker muscular dystrophies are collectively termed dystrophinopathy. Dystrophinopathy and severe childhood autosomal recessive muscular dystrophy (SCARMD) are clinically very similar and had not been distinguished in the early 20th century. SCARMD was first classified separately from dystrophinopathy due to differences in the mode of inheritance. Studies performed several years ago clarified some immunohistochemical and genetic characteristics of SCARMD, but many remained to be clarified. In 1994, the sarcoglycan complex was discovered among dystrophin-associated proteins. Subsequently, on the basis of our immunohistochemical findings which indicated that all components of the sarcoglycan complex are absent in SCARMD muscles, and the previous genetic findings, we proposed that a mutation of any one of the sarcoglycan genes leads to SCARMD. This hypothesis explained and predicted various characteristics of SCARMD at the molecular level, most of which have been verified by subsequent discoveries in our own as well as various other laboratories. SCARMD is now called sarcoglycanopathy, which is caused by a defect of any one of four different sarcoglycan genes, and thus far mutations in sarcoglycan genes have been documented in the SCARMD patients. In this review, the evolution of the concept of sarcoglycanopathy separate from that of dystrophinopathy is explained by comparing studies on these diseases.

Novel point mutations and allele loss at the RET locus in sporadic medullary thyroid carcinomas

Germline mutations in the RET proto-oncogene have been shown to be the underlying cause of multiple endocrine neoplasia type 2 (MEN 2A and 2B) and familial medullary thyroid carcinoma (FMTC). Some cases of sporadic medullary thyroid carcinoma (sporadic MTC) are reported to have specific codon 918, 883 and 768 mutations of the RET gene in tumor tissues. We examined RET gene mutations in 40 Japanese cases who had previously undergone surgery for sporadic MTC. DNA extracted from formalin-fixed tumor tissues and corresponding normal thyroid tissues or peripheral blood leukocytes was analyzed for mutations of exon 10, 11, 13, 14 and 16 of the RET gene by DNA sequencing and by mutation-specific restriction enzyme analysis. Germline RET point mutations were found in six of 40 cases (15%), cysteine residues at codon 618 in two, codon 634 in three and valine residue at codon 804 in one, and were newly identified as heritable MTC. Of the remaining 34 sporadic MTC cases, four (12%) had tumor-specific RET point mutations. Two were found in exon 16; one case showed an ATG to ACG (Met to Thr) mutation at codon 918, and the other showed two point mutations, ATG to ACG (Met to Thr) at codon 918 and GCA to GTA (Ala to Val) at codon 919 with loss of the wild-type allele, suggesting that both alleles at the RET locus were altered. The other two were found in exon 13; one case showed a CCG to TCG (Pro to Ser) mutation at codon 766 and the other showed a silent mutation, GTC to GTT (Val) at codon 778 with loss of the wild-type allele. There was no association of sporadic mutations with recurrence or prognosis in patients with sporadic MTC. The low rate of somatic RET mutation at codon 918 in our sporadic MTC suggests that as yet unknown factors may be involved. Genetic alterations in both alleles may have an important role in small fraction of sporadic MTCs.

Chronic thyroiditis as a favorable prognostic factor in papillary thyroid carcinoma

A subgroup of patients with papillary thyroid carcinoma (PTC) also has chronic thyroiditis (CT) as an associated disease of the thyroid. To assess the prognostic value of CT in patients with PTC, we reviewed the histological slides of 2225 patients with PTC who had undergone surgery between 1971 and 1992. Of the 2225 patients, 692 were excluded from the analysis because regional lymph nodes and/or nonneoplastic thyroid tissues were unavailable for histological assessment. The series included 281 patients with CT in nonneoplastic thyroid tissue and 1252 without CT. We performed statistical analyzes by the log-rank test and Cox's proportional-hazard method. Sixty-two (5.0%) of the 1252 patients without CT died of metastatic disease during the follow-up period and the relapse-free 10-year survival rate was 85%. By contrast, only 2 (<1.0%) of the 281 patients with CT died, and their relapse-free 10-year survival rate was 95%. The difference between patients with CT and those without CT in terms of relapse-free and overall survival was statistically significant (p < 0.0001). Risk factors for unfavorable outcome were age 45 years or more, absence of psammoma bodies, and absence of CT (p < 0.0001), followed by vascular invasion (p = 0.0007), male sex (p = 0.0013), and metastasis to regional lymph nodes (p = 0.047). Multivariate analysis indicated that all of these factors with the exception of gender were independent factors in the final model for overall survival. Chronic thyroiditis in the nonneoplastic thyroid of patients with PTC is a powerful prognostic factor for both relapse-free and overall survival.

[Long-term survival of bladder preservation therapy with radiation and chemotherapy for locally invasive bladder cancer]

The prognoses and prognostic factors of the 54 patients with locally invasive bladder cancer who underwent bladder preservation therapy at Yokohama City University Hospital between 1977 and 1995 were analyzed statistically. The therapeutic modalities of bladder preservation were mainly radiation or chemotherapy. The prognosis for the patients who underwent bladder preservation therapy was worse than that for the patients who underwent total cystectomy. The prognostic factors of these patients were size and grade of tumor, presence of hydronephrosis and performance status (PS) of the patients by univariate analysis. Tumor grade was the most predictable prognostic factor using multivariate analysis. Only 17 patients survived more than 5 years after treatment; 78% of the survivors had good PS (0 or 1). Five of them died of cancer and two patients were alive with cancer. All of them had G3 tumors. These results suggest that patients with locally invasive G2 tumor could be candidates for bladder preservation therapy and patients who underwent bladder preservation therapy should be evaluated at 10 years post-therapy.

Papillary thyroid carcinoma: modified radical neck dissection improves prognosis

OBJECTIVE

To ascertain whether modified radical neck dissection offers a survival advantage for some subsets of patients with papillary cancer of the thyroid.

DESIGN

A retrospective cohort study of 2966 patients curatively treated at the Noguchi Thyroid Clinic and Hospital Foundation, Oita, Japan, between 1946 and 1991.

SETTING

A center for the treatment of thyroid disease, where about 1400 thyroid operations are performed per year.

PATIENTS

Between 1946 and 1991, patients with papillary cancer whose primary tumor was 1 cm or larger and who were curatively treated were studied. Of the 2859 patients, 72.1% underwent modified radical neck dissection, 8.5% underwent partial node excision, and 19.4% underwent no node excision.

RESULTS

A univariate analysis revealed a subset of patients who benefited from modified radical neck dissection. A multivariate analysis revealed that sex (P<.001), age at the time of the operation (P<.001), size of the primary tumor (P<.001), extrathyroidal invasion (P<.001), and the presence of nodal metastasis (P<.01) are significant risk factors.

CONCLUSION

Patients with nodal metastasis, patients in whom the primary tumor invades beyond the thyroid capsule, and women older than 60 years can benefit from modified radical neck dissection.

Production of immunoreactive 2',5'-oligoadenylate synthetase in p48-deficient mice

2',5'-Oligoadenylate synthetase (2'5'OAS), an enzyme induced by interferon (IFN), is physiologically produced in IFN-untreated normal healthy mice. The enzyme is localized mainly in the epithelium of the digestive tract, reproductive organs, and the choroid plexus in the brain. 2'5'OAS is also detected in oocytes in the ovary and in neurons and glial cells of both the telencephalon and cerebellum. Here, we examined the role of p48 (ISGF3gamma), a component of IFN-stimulated gene factor 3 (ISGF3), in the physiologic production of 2'5'OAS using p48-deficient mice generated by gene targeting. In the p48-deficient mice, the physiologic production of 2'5'OAS localized in the following cells was severely impaired: hepatocytes, Kupffer cells, splenocytes, epithelium of the large intestine, oviduct, and uterus, and neurons and glial cells in both the telencephalon and cerebellum. The results show that 2'5'OAS in these cells is induced physiologically through a pathway including p48. However, the production of 2'5'OAS in oocytes was not affected in the p48-deficient mice, indicating that oocyte 2'5'OAS is produced through a p48-independent pathway. A possible function of the GAS sequence found in the promoter region of the 2'5'OAS gene to which Stat6 may bind also is discussed.

Expression of splice variants of CD44 in thyroid neoplasms derived from follicular cells

Isoform expression of CD44 in follicular carcinoma (FC) of the thyroid was analyzed by immunohistochemical staining and compared to the isoforms in follicular adenoma (FA) and papillary carcinoma (PC) of the thyroid. Variant isoforms of CD44 (CD44v) were detected in these neoplastic cells but not in non-neoplastic cells. CD44v6 was expressed in PC with nodal metastasis and also in FC at significantly higher frequencies than those in PC without metastasis and FA. The frequency of expression of CD44v3 was significantly higher in PC with nodal metastasis than in PC without metastasis. The reverse transcription-polymerase chain reaction (RT-PCR) followed by Southern blotting analysis revealed the presence of a transcript for a variant of CD44 that contained variant exon 6 in FA, FC and PC. DNA sequencing of the products of RT-PCR yielded three species of cDNA for CD44v. One of the cDNA corresponded to a transcript that contained variant exon 6. These results suggest that immunohistochemical staining and RT-PCR with Southern blotting analysis for CD44v6 might be a useful diagnostic tool for the differentiation of FC from FA and that the expression of CD44v3 and CD44v6 might be important for the development of nodal metastasis in cases of PC.

Type I interferons are essential mediators of apoptotic death in virally infected cells

BACKGROUND

The interferons (IFNs) have been extensively studied in the context of host defence against viral infection. In the established model of IFN action, virally infected cells secrete type I IFNs (IFN-alpha/beta) which induce an antiviral state in uninfected cells. However, it is not clear how IFNs function on the infected cells. It has been reported that cells infected by some viruses die by apoptosis.

RESULTS

In the present study, we found that three types of viruses commonly induce apoptosis in primary cell cultures. Importantly, we observed that virus-induced apoptosis was inhibited by anti-IFN-alpha/beta antibodies, and in cells lacking either the type I IFN receptor 1 (IFNAR1) or its downstream mediator, Stat1 (Signal transducer and activator of transcription 1). IFN-alpha treatment by itself did not induce apoptosis unless it was combined with transfection by double-stranded RNA (dsRNA), which is normally generated during the course of viral infection.

CONCLUSION

These results indicate a novel antiviral function of the type I IFNs, i.e. the selective induction of apoptosis in virally infected cells. In effect, these IFNs have a bifunctional role in limiting the spread of virus; eliciting an antiviral state in uninfected cells while promoting apoptosis in infected cells. Our results may help explain why IFNs are sometimes useful in the treatment of viral diseases and will provide further insight into the mechanisms of virus-induced pathogenesis.

Monitoring of serum levels of HCV RNA in early phase of IFN therapy; as a predictive marker of subsequent response

BACKGROUND/AIMS

To determine whether the initial response to interferon (IFN) therapy predicts the long-term response, monitoring of HCV RNA level in the early phase of IFN therapy was performed.

METHODOLOGY

Sixty-seven patients with chronic hepatitis C virus (HCV) infection were investigated. Patients received 6 MU of human lymphoblastoid IFN daily for 2 weeks and then three times weekly for 22 weeks (total dose; 480 U). These were 34 complete responders (CR) and 33 non-responders (NR). Serum levels of HCV RNA were assayed before therapy and at weeks 1 and 2, using the AMPLICOR HCV Monitor kit.

RESULTS

Serum levels of HCV RNA were below the detection limit in 33 (97.1%) of 34 CR compared with 13 (39.4%) of 33 NR at week 1, and in 100% of CR compared with 17 (51.5%) of NR at week 2 (P < P0.05). These observations were independent with viral genotypes.

CONCLUSION

A complete response to IFN therapy results primarily from a rapid decrease in the serum levels of HCV RNA and a further decrease to below the detection limit by week 2 of the therapy. In spite of a viral genotype, early monitoring of serum levels of HCV RNA during IFN therapy are predictive of a subsequent long-term response to IFN in patients with chronic HCV infection.

Prognostic significance of Ki-67, p53, and Bcl-2 expression in prostate cancer patients with lymph node metastases: a retrospective immunohistochemical analysis

The prognostic significance of Ki-67, p53, and Bcl-2 expression was evaluated in prostate cancer patients with lymph node metastases. Immunohistochemical staining of archived material obtained from 56 patients was performed by the streptavidin-biotin method. Univariate survival analysis showed that a Ki-67 labeling index (Ki-67 LI) of > or = 8.4 in the primary tumor identified a group of patients with a significantly poorer prognosis (P < 0.001). furthermore, a Ki-67 LI of > or = 8.7 in the nodal metastatic tumor was also associated with a poorer prognosis (P < 0.01). Multivariate analysis showed that the Ki-67 LI of primary tumors (P < 0.01) and lymph node metastases (P < 0.01) had independent prognostic value. p53 and Bcl-2 expression had no prognostic value in patients with prostate cancer and lymph node involvement. The Ki-67 LI has more prognostic value than p53 and Bcl-2 expression for patients with prostate cancer that has spread to the lymph nodes.

Prognostic significance of Ki-67 expression in transitional cell bladder carcinoma after radical cystectomy

We evaluated the prognostic significance of the Ki-67 labeling index (Ki-67 LI) in 75 patients with transitional cell carcinoma of the bladder who underwent radical cystectomy. Immunohistochemical staining of archival material was performed by the streptavidin-biotin method. Univariate survival analysis showed that Ki-67 LI (p < 0.001), histologic grade (p < 0.05), tumor stage (p < 0.001) and the number of positive lymph nodes (p < 0.001) significantly correlated with prognosis. Multivariate survival analysis indicated that the Ki-67 LI (p < 0.05), histologic grade (p < 0.01), tumor stage (p < 0.01), presence of lymph node metastases (p < 0.05) and use of neo-adjuvant therapy (p < 0.05) had independent prognostic value. The Ki-67 LI is an independent prognostic factor for patients with transitional cell bladder cancer treated by radical cystectomy.

Extracapsular invasion of lymph node metastasis is an indicator of distant metastasis and poor prognosis in patients with thyroid papillary carcinoma

BACKGROUND

In patients with thyroid papillary carcinoma, age and the presence or absence of distant metastasis are regarded as the main prognostic factors. However, the histologic characteristics of thyroid papillary carcinoma that develops distant metastasis have not yet been clarified.

METHODS

The histologic findings and prognosis of 50 patients with thyroid papillary carcinoma who later developed distant metastasis (metastatic group) were compared with those of 50 patients without local recurrence or distant metastasis (control group). The age, tumor size, and gender ratio of the control group were matched with those of the metastatic group. Univariate analyses (chi-square test and/or Fisher's exact test) and multivariate analyses (logistic regression) were performed.

RESULTS

Univariate analyses showed that the incidence of nonpure papillary carcinoma, absence of bone at the periphery of the tumor, invasion of the perithyroidal muscle, large lymph node deposits, and extranodal invasion were significantly higher in the metastatic group. Multivariate analyses revealed that only extranodal invasion was statistically significant (P = 0.0045) and that the odds ratio of extranodal invasion in distant metastasis was 9. Moreover, the risk of death from thyroid carcinoma was higher among the patients with extranodal invasion than those without (P <0.01).

CONCLUSIONS

The presence of extranodal invasion in patients with thyroid papillary carcinoma is an indicator of distant metastasis and poorer prognosis.

Subcellular localization of Bcl-2 protein in synovial sarcoma

The subcellular localization of Bcl-2 protein in surgically resected, fixed-frozen tissue specimens of seven tumors from six cases of synovial sarcoma and a synovial sarcoma cell line was examined using laser-scanning confocal microscopy and immunoelectron microscopy. Bcl-2 protein in synovial sarcoma cells was detected in the nuclear envelope, endoplasmic reticulum membrane, and mitochondrial circumference. Based on the finding of pre-embedding immunoelectron-microscopy observation, the distribution of Bcl-2 protein in such membranous organella was patchy. A computer-based image analysis failed to reveal any quantitative differences between the inner and the outer mitochondrial membranes. The tumorigenesis of synovial sarcoma is also discussed from the viewpoint of Bcl-2 overexpression.

A case-control study on risk factors for local recurrences or distant metastases in breast cancer patients treated with breast-conserving surgery

A case-control study was conducted on 143 case-control sets recruited from the 18 key hospitals/ institutes in Japan to identify risk factors for local recurrences and distant metastases after breast-conserving surgery in breast cancer patients: (1) positive surgical margin was a risk factor for local recurrences (relative risk (RR) = 16.70, p < 0.001) but not for distant metastases, (2) positive p53 immunostaining was a risk factor for both local recurrences (RR = 5.62, p = 0.003) and distant metastases (RR = 3.11, p = 0.034), (3) lymph node metastasis was a risk factor for distant metastases (RR = 9.28, p = 0.001) but not for local recurrences, (4) radiation therapy reduced local recurrences (RR = 0.13, p = 0.004) and (5) adjuvant chemotherapy (RR = 0.27, p = 0.120), endocrine therapy (RR = 0.21, p = 0.037), and chemoendocrine therapy (RR = 0.05, p = 0.013) reduced local recurrences.

[A case of stage IVb gastric cancer effectively treated by neoadjuvant chemotherapy and total gastrectomy with no residual tumor (R0)]

PA 72-year-old man visited our hospital complaining of body-weight loss and appetite loss. The upper gastrointestinal series and gastrointestinal fibroscopy disclosed a Borrmann 3 type gastric cancer. Laparoscopic examination revealed peritoneal dissemination (P2). Continuous intravenous administration of 5-FU (500 mg/day) for three weeks and drip infusion of CDDP (10mg/day) five days per week every three weeks was given as neoadjuvant chemotherapy. This course was carried out twice. Then laparoscopic reexamination revealed complete disappearance of disseminated lesions of the peritoneum, and total gastrectomy with R0 was done. Histopathological finding of the resected specimen showed significant effects of the neoadjuvant chemotherapy. The patient has been doing well with keeping good performance status (PS) 0 for one year and seven months after first diagnosis.

Thyroid cancer associated with adenomatous goiter: an analysis of the incidence and clinical factors

We evaluated the incidence of thyroid cancer in patients with adenomatous goiter and investigated the clinical factors distinguishing patients with occult thyroid cancer, defined as a tumor size smaller than or equal to 10 mm, from those with clinical thyroid cancer, defined as a tumor size larger than 10 mm. Of 835 patients with histologically confirmed adenomatous goiter, 256 (30.7%) also had thyroid cancer, being occult in 137 patients and clinical in 119 patients. There was no correlation between the maximum size of the thyroid cancer tumor and the age of the patient, and the percentage of patients with thyroid cancer in each group was not influenced by age. There were no significant differences in age, sex, the serum concentrations of free triiodothyronine, free thyroxine, thyrotropin, and thyroglobulin, or the urinary iodine creatinine ratio. The frequency of calcified lesions being detected by ultrasonography (US) and/or neck X-ray in the patients with clinical thyroid cancer was significantly greater than that in those with occult cancer at 83% vs 57%, respectively (P < 0.0001). This study disclosed a high prevalence of thyroid cancer associated with adenomatous goiter, and the results suggest that a considerable number of associated carcinomas remain occult. The detection of calcification in the thyroid gland is one of the surgical indications for patients with adenomatous goiter.

[Prevalence of prolonged APTT and lupus anticoagulant in autoimmune thyroid disease]

We describe prevalences of prolonged activated partial thromboplastin time(APTT) and lupus anticoagulant(LAC) in autoimmune thyroid disease(AITD). Prolonged APTTs were observed in 33(6.2%) blood samples out of 532 AITD cases(327 Graves' diseases and 205 Hashimoto's thyroiditis), but in only 8(2.0%) samples out of 396 non AITD cases(213 thyroid tumors, 14 subacute thyroiditis and 169 normal thyroids). The samples with prolonged APTT showed no abnormality in coagulation factors(factor VIII, IX, XI, XII, von Willebrand factor(vWF), prekallikrein, or high molecular weight kininogen) or factor VIII, IX inhibitor. Among samples with prolonged APTT, LAC evaluated by platelet neutralization procedure(PNP) was positive in 17(51.5%) samples of AITD, and in 2(25.0%) samples of non AITD. In prolonged APTT cases, the frequency of fetal loss in patients with AITD was higher than non AITD patients. But no significant difference was obtained between thyroid autoimmune antibody and the frequency of fatal loss. These indicate unknown biological association of between AITD and LAC.

Effect of tamoxifen on pS2 expression in human breast cancers

pS2 protein expression is induced by estrogen through estrogen receptors (ER), and is known to be inhibited by antiestrogen in the breast cancer cell line MCF-7. The present study was undertaken to determine whether pS2 expression may be inhibited by the antiestrogen tamoxifen (TAM) human breast cancer. pS2 expression was immunohistochemically investigated in 22 patients treated preoperatively with TAM and in 45 without TAM treatment (control group). Immunostaining was considered positive when 10% of tumor cells showed cytoplasmic staining. We found that 94% of the pS2-positive tumors were ER-positive (ER+), and there was a significant association between the two proteins (p < 0.0001). In ER+ tumors, pS2 expression was seen in only 21% (3 of 14) of the TAM+ group, compared to 70% (16 of 23) of the control group. Statistical analysis of these data indicated a high likelihood (p = 0.006) of TAM treatment being associated with inhibition of pS2 expression in human breast cancers.