Calcified and ossified phlebosclerosis]

Eight cases of dystrophic calcification and/or ossification within the walls of deep and superficial leg veins were analyzed and histologically examined. Calcification of superficial veins is a frequent clinical finding. Calcification of deep veins is occasionally observed. Ossification of the venous wall, however, has been rarely described. Calcification and ossification of the venous wall always concern the intimal layer or an organized thrombus and do not involve the media. This is in contrast to the findings in arteries where calcification and ossification of the media is frequent (M?nckeberg's mediasclerosis). The clinical consequences of calcification and ossification in the venous wall are briefly discussed.     

Abdominal tuberculosis--a retrospective analysis of 121 cases.

From 1960 to 1989, a total of 121 patients with abdominal tuberculosis were treated at this hospital. Ages, at the time of diagnosis, ranged from 14 years to 81 years with a mean of 44 years. There were 86 males and 35 females. No clinical feature was diagnostic, but the leading presenting complaints were abdominal pain (79%) and fever (53%). Chest x-ray showed that 80 patients (69%) had coexisting evidence of pulmonary tuberculosis. Lesions were most commonly located at the ileocecal region (40%). The diagnosis was bacteriologically established in only 39 patients (32%). It was difficult to obtain the definitive diagnosis, most of our patients (91 cases) were diagnosed while undergoing laparotomy with tissue biopsy. Although the principal treatment of abdominal tuberculosis was chemotherapy and operation should be reserved until complications occurred, there were still 96 patients (79%) who underwent surgical procedures. The reasons of high operative rate were the difficulty of early diagnosis and the delay of proper treatment. The common complications of abdominal tuberculosis and the related managements were discussed and the findings in our cases which were helpful in diagnosing abdominal tuberculosis were also presented. Sixteen severely ill patients who died tended to be older, poor nutrition and associated with underlying medical diseases. Abdominal tuberculosis is still persistent in Taiwan, and it must be included in the differential diagnosis of obscure abdominal conditions to avoid diagnostic delay and unnecessary illness and death.     

A background to nuclear transfer and its applications in agriculture and human therapeutic medicine

The development of a single celled fertilized zygote to an animal capable of reproduction involves not only cell division but the differentiation or specialization to numerous cell types forming each tissue and organ of the adult animal. The technique of nuclear transfer allows the reconstruction of an embryo by the transfer of genetic material from a single donor cell, to an unfertilized egg from which the genetic material has been removed. Successful development of live offspring from such embryos demonstrates that the differentiated state of the donor nucleus is not fixed and can be reprogrammed by the egg cytoplasm to control embryo and fetal development. Nuclear transfer has many applications in agriculture and human medicine. This article will review some of the factors associated with the success of embryo development following nuclear transfer and outline the potential uses of the technology.     

Serial depletion and regeneration of the murine hematopoietic system. Implications for hematopoietic organization and the study of cellular aging

The mouse hematopoietic system was subjected to repeated depletion and regeneration either by serial transfer of bone marrow cells through lethally irradiated recipients or by repeated treatment with the cycle-active drug hydroxyurea (HU). The capacity of surviving stem cells to proliferate and self-renew was assayed at intervals by two methods: (a) the spleen colony method; and (b) competitive repopulation of irradiated recipients using chromosome markers, with normal bone marrow cells as an internal control. The progressive decline in stem cell function that occurred during serial transfer of bone marrow and that had already begun after a single transfer was not seen during HU treatment; up to 25 pairs of HU injections given over more than 1 yr had no discernible effect on the number of stem cells present 3 wk after the final injection or on their capacity to self-renew. Within 2 d after exposure to HU, the average self-renewal capacity of surviving stem cells was enhanced. This implies that the drug selectively eliminates poorly self-renewing stem cells and hence that these enter cycle more readily than stem cells with a high self-replicative potential. However, the fact of being in cycle at the time of injection did not of itself affect self-renewal. The results show that serial transfer of bone marrow is not a valid method for studying clonal aging phenomena because it does not fulfill the assumptions on which such studies are based. No evidence was obtained for any intrinsic limitation in the capacity of bone marrow populations for repeated regeneration after HU-induced depletion. However, this does not necessarily imply that individual hematopoietic clones are capable of indefinite expansion because hematopoiesis may (as suggested by the relative resistance of highly self-replicative stem cells to mitogenic signals) proceed on the basis of clonal succession.     

Decreased expression of type Ⅱ tumor suppressor gene RARRES3 in tissues of hepatocellular carcinoma and cholangiocarcinoma

AIM: To analyze the expression of retinoic acid receptor responder 3 (RARRES3) protein in paraffin-embedded tissues of hepatocellular carcinoma (HCC) and cholangiocarcinoma(CC), and the correlation of RARRES3 production with tumor differentiation.METHODS: Expression of RARRES3 in tissues from 21CC (10 well-, 7 moderately- and 4 poorly-differentiated)and 32 HCC was determined by immunohistochemistry.RESULTS: Among 21 CC tissues, RARRES3 was detected in 8 (80%) of 10 well-differentiated tumors. Only 2 (18.2%)out of 11 tumors with moderate or poor differentiation showed positive RARRES3 expression. RARRES3 expression in well-differentiated CC was significantly higher than that in tumors with moderate or poor differentiation (Fisher exact test, P＜0.01). Expression of RARRES3 was not different between early (Ⅰ and Ⅱ) and late (Ⅲ and Ⅳ) stages of CC.Among 30 HCC tissues, 17 (56.7%) weakly expressed RARRES3 in HCC cells, and 25 (83.3%) normal tissues adjacent to HCC expressed the protein. RARRES3 expression was significantly decreased in HCC tissues compared to that in adjacent normal tissues (logistic regression analysis, OR = 0.27, 95% CI (0.11-0.62), P＜0.01).CONCLUSION: Expression of RARRES3 is positively correlated to well-differentiated CC, which supports the role of RARRES3 in malignant epithelial differentiation of the tumor. The decrease in RARRES3 expression in tissues of HCC and CC with moderate and poor differentiation suggests that altered RARRES3 expression may play a role in the carcinogenesis of the liver and biliary tract.     

Effect of substance P and protein kinase inhibitors on β-amyloid peptide-induced proliferation of cultured brain cells

The present study investigated the effect of substance P (SP) and protein kinase inhibitors (H7 and HA1004) on β-amyloid peptide-induced proliferation of neonatal rat brain cells in primary cultures. The β-amyloid peptide_1–28 (designated as βAP28), at nanomolar concentrations (10⁻⁹ M), significantly (P 0.05) increased the proliferation of brain cells (presumably non-neuronal) as measured by [³H]thymidine uptake into DNA (mitogenesis). The effect was dependent on time of cultured, concentration of βAP28, and presence of fetal calf serum. The supplementation of SP into cell cultures at time zero reversed the proliferative response of βAP28. Moreover, the βAP28-induced proliferation was inhibited by protein kinase inhibitor H7, but not by HA1004. Since H7 is a selective protein kinase C (PKC) inhibitor and SP action involves PKC, we conclude that βAP28 induces normal brain cell proliferation through PKC pathway of cell signaling.