Malignant lymphoma in southern Taiwan according to the revised European-American classification of lymphoid neoplasms

BACKGROUND

The purpose of the current study was to determine the distribution and relative frequency of each subtype of malignant lymphoma in southern Taiwan according to the revised European-American classification of lymphoid neoplasms (REAL).

METHODS

The pathology files of a regional hospital in southern Taiwan for 1989-1998 were searched for malignant lymphoma, lymphoproliferative disorder, and Hodgkin disease (HD). The results of light microscopy, immunohistochemistry, and in situ hybridization for Epstein-Barr virus-encoded RNA (EBER) were correlated with clinical findings, and all cases were classified according to REAL.

RESULTS

A total of 205 cases were analyzed retrospectively. There were 197 cases (96.1%) of non-Hodgkin lymphoma (NHL) and 8 cases (3. 9%) of HD. Among the 197 NHL cases, 161 (81.7%) were of B-cell lineage and 36 (18.3%) were of T-/natural killer cell lineage. Diffuse large B-cell lymphoma, extranodal marginal zone lymphoma, and follicular lymphoma were the most common B-cell subtypes and represented 47.2%, 19.3%, and 6.1%, respectively, of all NHL cases. Among the 36 cases of T-/natural killer cell lineage, unspecified peripheral T-cell lymphoma (8.6%), T-/natural killer cell lymphoma (angiocentric lymphoma) (4.1%), and anaplastic large cell lymphoma (3.6%) were the most common subtypes. Seven of eight T-/natural killer cell lymphoma cases were positive for EBER. The eight cases of HD were classified as lymphocyte-rich classic (two cases), nodular sclerosis (two cases), and mixed cellularity (four cases) subtypes. Three of these eight cases were positive for EBER.

CONCLUSIONS

To the authors' knowledge this study is the first in Taiwan using the REAL classification and it again confirms the different geographic distribution of the various subtypes of malignant lymphoma. The frequency of T-/natural killer cell lineage NHL in Taiwan is higher than that in Western countries but not as high as reported previously.

Special postpartum dietary practices of Hong Kong Chinese women

OBJECTIVE

A 'ginger vinegar soup' and other special dietary practices have been traditionally recommended for postpartum Chinese women. This paper describes these practices in the first 6 weeks postpartum, and details of the calcium and iron content of the 'ginger vinegar soup'.

DESIGN AND SUBJECTS

Results of this paper were generated from a longitudinal study on the nutritional status of Hong Kong Chinese postpartum women. 'Ginger vinegar soup' samples were collected at the 2 week home visits. Calcium and iron content were measured by the combination of dry ashing method and atomic absorption spectrophotometry. Results were compared with other types of soup and food sources. A food frequency questionnaire was completed at the 6 week interview to assess the special dietary practices during this period.

RESULTS

Fifty-one subjects completed the food frequency questionnaires. Twenty-two ginger vinegar soup samples and six other soup samples were collected. Consumption of special food items such as ginger, pig's trotters, egg and chicken varied greatly among subjects. More poultry and similar amounts of egg were consumed by our subjects as compared with the Hong Kong general population. Chicken soup and ginger vinegar soup were commonly consumed. Median calcium and iron contents of the ginger vinegar soup were 4.65 and 0.84 mg/dl, respectively. This calcium content was higher than that of the other six soup samples, but was low as compared with other calcium-rich foods. Iron content of ginger vinegar soup was higher than that of the other six samples and was comparable to some iron-rich foods.

CONCLUSIONS

Hong Kong Chinese postpartum women followed traditional dietary practices to different degrees. These practices were characterized by an increased poultry consumption. Iron content of ginger vinegar soup was comparable to some iron-rich foods.

Epithelial-myoepithelial carcinoma arising in pleomorphic adenoma of the palate

A case of epithelial-myoepithelial carcinoma (EMC) in pleomorphic adenoma (PA) occurring in the palate of a 72-year-old woman is reported. The tumor was composed of 2 different components, PA and EMC, accounting for approximately 40% and 60% of the whole tumor, respectively. The EMC showed multiple tubular or solid nests, which were separated by a basement membrane and consisted of variable proportions of 2 cell types, cuboidal epithelial cells positive for cytokeratin and clear myoepithelial cells positive for glial fibrillary acid protein, whereas the myoepithelial nests of PA intermingled with hyaline and myxoid stroma. The malignancy was demonstrated by convincing evidence of invasion into the submucosa, although the EMC component was mostly surrounded by the PA components. An increased immunoreactivity of proliferating cell nuclear antigen in the EMC area in comparison to the PA area also suggested EMC arising in a PA.

Bone marrow histochemical studies of fibrogenic cytokines and their receptors in myelodysplastic syndrome with myelofibrosis and related disorders

Cellular and extracellular alterations of various fibrogenic cytokines have been described in a number of different chronic myeloid disorders that are associated with myelofibrosis. However, the available information related to both myelodysplastic syndrome with myelofibrosis (MDS-f) and bone marrow histochemical analysis is limited. In the current study, bone marrow immunohistochemical staining for platelet-derived growth factor, transforming growth factor (TGF)-beta, basic fibroblast growth factor (bFGF), and their receptors was performed in 9 patients with MDS-f, 9 patients with essential thrombocythemia (ET), 8 patients with 5q- syndrome, and 5 healthy control subjects. In addition, TGF-beta1 messenger RNA (mRNA) analysis was performed in 5 patients, each with MDS-f, myelofibrosis with myeloid metaplasia (MMM), polycythemia vera (PV), ET, and immune thrombocytopenic purpura, and in healthy control subjects. In general, protein and transcript expression patterns were similar to normal patterns and not significantly different among the various disease groups. The only exception was a reduced concentration of bFGF-expressing stromal cells in patients with PV, ET, and MMM.

Breastfeeding failure in a longitudinal post-partum maternal nutrition study in Hong Kong

OBJECTIVE

To describe factors associated with breastfeeding failure during the first 6 months post-partum in a sample of Hong Kong Chinese women participating in a longitudinal study of maternal nutrition.

METHODOLOGY

Forty-four Hong Kong Chinese lactating mothers who intended to breastfeed exclusively for at least 3 months were recruited and followed for 6 months post-partum. Demographic data were compared with 20 mothers who intended to use formula feeding. Mothers were followed up at 2 and 6 weeks and 3 and 6 months and details of infant feeding practices were obtained. Information was sought on breastfeeding management in hospital, reasons for discontinuation of breastfeeding or for providing supplements to babies and intention to seek, and sources of, lactation support.

RESULTS

Thirty-nine mothers who planned to breastfeed completed the follow up. Compared with mothers in the formula-feeding group, breastfeeding mothers were more likely to be professionals or housewives. Continuation of any breastfeeding (total and partial) was noted in 30 (77%), 22 (57%), 16 (41%) and 12 (31%) mothers at 2 and 6 weeks and 3 and 6 months post-partum, respectively. The majority (97%) of mothers stated that they were given information on the benefits and management of breastfeeding. However, late initiation of breastfeeding and providing supplements to babies were common. Perceptions of insufficient milk supply (44%), breast problems (31%) and being too tired (28%) were the main reasons stated for stopping breastfeeding or for providing supplements to babies. Midwives from the postnatal wards and hotlines were the main sources of lactation support.

CONCLUSIONS

These results highlight difficulties in sustaining breastfeeding, either exclusive or partial, in Hong Kong Chinese women. Despite being recruited on the basis of intending to exclusively breastfeed for 3 months, less than half these mothers were still breastfeeding and only approximately one-third were exclusively or predominantly breastfeeding at 3 months. More needs to be done within the hospital environment to initiate breastfeeding immediately after birth and to avoid giving unnecessary supplements and more effort is needed to foster a mother's confidence, commitment and knowledge of breastfeeding.

Megakaryocyte c-Mpl expression in chronic myeloproliferative disorders and the myelodysplastic syndrome: immunoperoxidase staining patterns and clinical correlates

The objectives of this study were to expand on recent observations that have suggested decreased thrombopoietin receptor (c-Mpl) expression in megakaryocytes of patients with polycythemia vera (PV) and agnogenic myeloid metaplasia (AMM). We applied an immunoperoxidase method with anti-c-Mpl antibody to 55 bone marrow sections from previously untreated patients with chronic myeloproliferative disorder (CMPD) or myelodysplastic syndrome (MDS). These included 8 patients with PV, 15 with AMM, 9 with essential thrombocythemia, 5 with chronic myelocytic leukemia, 9 with the 5q-syndrome and 9 with MDS with fibrosis. The findings were compared with those in four patients with reactive erythrocytosis (RE), six with immune thrombocytopenic purpura (ITP) and five normal controls. Staining intensity (SI) was moderate to strong both in normal controls and in patients with RE or ITP. In contrast, SI was weak in variable proportions of the megakaryocytes in every one of the aforementioned clonal myeloid disorders. The staining pattern (SP) was relatively uniform in MDS and heterogeneous in CMPD. Neither SI nor SP was significantly correlated with certain clinical or laboratory parameters. We concluded that altered megakaryocyte c-Mpl expression may be a nonspecific phenomenon in various subtypes of both CMPD and MDS. However, the characteristic staining patterns may complement the morphological distinction between clonal and reactive myeloproliferation.

Bacterial endobionts in the big non-mycorrhizal roots of Scots pine (Pinus sylvestris L.)

Subsurface bacterial growth occurred in an N-free medium inoculated with interior tissues of big non-mycorrhizal roots (7 to 8 mm diameter) of 15-20 years-old Scots pine (Pinus sylvestris L.) growing on sand dunes at the Baltic Sea of Poland. The bacteria were not N2 fixers as determined by the acetylene reduction method. Light microscopic and scanning electron microscopic observations revealed massive bacterial clusters residing in the cortical cells underlying epidermis and parenchyma. The bacteria produced yellow-green pigments on King's medium, which fluoresced under ultraviolet (UV) irradiation at 366 nm wavelength, and could be a siderophore-producing Pseudomonas.

Combination treatment of murine tumors by adenovirus-mediated local B7/IL12 immunotherapy and radiotherapy

Failure of local tumor control still poses a problem for radiotherapy and translates into reduced survival. Combining radiation with chemotherapy or other newer modalities has shown promising results. Immunological approaches to tumor therapy have found renewed interest due to improved insight into mechanisms involved in the immune response to tumors. In this paper, we studied tumor growth delay after various combination regimens of locally injected adenovirus constitutively expressing IL12 and B7.1 (AdIL12/B7.1) and fractionated radiotherapy in two nonimmunogenic murine tumor models, 4T1 and B16.F10. Effects of radiation and virus infection on surface antigen expression in these tumor lines were assessed. Mechanisms of action of AdIL12/B7.1 were studied by conducting additional experiments with and without depletion of NK-cells and/or T-cells, and by cytotoxic T-lymphocyte assays, and immunohistochemical evaluation of tumor blood vessels. Both B7.1 and IL12 were effectively expressed in both irradiated and unirradiated 4T1 and B16.F10 tumor cells but did not add significantly to radiation-induced cell killing in vitro. However, local tumor infection by AdIL12/B7.1 after irradiation significantly increases the effectiveness of radiotherapy when applied after completion of radiotherapy. The mechanism appears to be complicated, involving a host of factors that included the ability of IL12 to activate T-cells and NK-cells and to inhibit angiogenesis and the ability of radiation to induce apoptosis or necrosis among tumor cells. These data support the combination of radiotherapy with adenovirus-mediated immunotherapy and suggest that the concept of adding genetic immunotherapy after radiotherapy in a combined regimen merits further study.

Heat shock protein 70 inhibits apoptosis downstream of cytochrome c release and upstream of caspase-3 activation

Heat shock protein 70 (HSP70) has been shown to act as an inhibitor of apoptosis. We have also observed an inhibitory effect of HSP70 on apoptotic cell death both in preheated U937 and stably transfected HSP70-overexpressing U937 (U937/HSP70) cells. However, the molecular mechanism whereby HSP70 prevents apoptosis still remains to be solved. To address this issue, we investigated the effect of HSP70 on apoptotic processes in an in vitro system. Caspase-3 cleavage and DNA fragmentation were detected in cytosolic fractions from normal cells upon addition of dATP, but not from preheated U937 or U937/hsp70 cells. Moreover, the addition of purified recombinant HSP70 to normal cytosolic fractions prevented caspase-3 cleavage and DNA fragmentation, suggesting that HSP70 prevents apoptosis upstream of caspase-3 processing. Because cytochrome c was still released from mitochondria into the cytosol by lethal heat shock despite prevention of caspase-3 activation and cell death in both preheated U937 and U937/hsp70 cells, it was evident that HSP70 acts downstream of cytochrome c release. Results obtained in vitro with purified deletion mutants of HSP70 showed that the carboxyl one-third region (from amino acids 438 to 641) including the peptide-binding domain and the carboxyl-terminal EEVD sequence was essential to prevent caspase-3 processing. From these results, we conclude that HSP70 acts as a strong suppressor of apoptosis acting downstream of cytochrome c release and upstream of caspase-3 activation.

Longest held occupation in a lifetime and risk of disability in activities of daily living

OBJECTIVES

To examine the association between the longest held occupation in a lifetime and risk of disability in activities of daily living (ADL) among elderly people (65 years and older) in northern Taiwan.

METHODS

A case-control design was used nested within two cohorts of a total of 2198 elderly people who had been followed up either between 1993 and 1997 or between 1996 and 1997. Cases were 360 elderly people with ADL disability within the study period. For each case, two sex matched controls were randomly sampled from the pool of elderly people free from ADL disability. Occupational data were collected through interviews conducted in 1997. Performed job contents were classified into occupational categories and occupation based social classes. Unconditional logistic regression techniques were used to estimate relative risk and 95% confidence intervals (95% CIs) of ADL disability.

RESULTS

Compared with people who were former legislators, government administrators, or business executives and managers, workers in agriculture, animal husbandry, forestry, or fishing (odds ratio (OR) 1.9, 95% CI 1.1 to 3.5) and workers in craft and related trades (OR 1.9, 95% CI 1.1 to 3.4) had significantly increased risks of subsequent ADL disability. Differential risks of ADL disability were found across social classes, with a significant dose-response trend in which unskilled blue collar workers had an 1.8 times higher risk of ADL disability than higher social classes of white collar workers.

CONCLUSIONS

After adjustment for education, there was still an inverse relation between risk of ADL disability and social class. Although total control for all the known risk factors for ADL disability among elderly people was impossible, the results tend to suggest a potential for an effect of longest held occupation in a lifetime on risk of ADL disability.

Immunohistochemical staining for megakaryocyte c-mpl may complement morphologic distinction between polycythemia vera and secondary erythrocytosis

Recent studies have shown decreased megakaryocyte expression of the thrombopoietin receptor (c-mpl) in patients with polycythemia vera (PV) but not in those with reactive erythrocytosis. We examined the diagnostic utility of this observation in 22 patients with PV, 7 patients with secondary erythrocytosis (SE), and 10 normal controls. Commercial antibodies against c-mpl were used with standard immunoperoxidase methods. Megakaryocyte c-mpl staining intensity was uniformly moderate-to-strong in the healthy controls and in all the patients with SE. In contrast, staining intensity in 9 patients with PV (41%) was uniformly weak. Furthermore, in 12 of the remaining 13 patients with PV, the c-mpl staining pattern in each case was heterogeneous and was associated with weak staining intensity in more than 20% of the megakaryocyte population. These preliminary data suggest that c-mpl immunostains may complement bone marrow histopathology in distinguishing PV from nonclonal causes of erythrocytosis. (Blood. 2000;96:771-772)

Image analysis and flow cytometric DNA studies of benign and malignant body cavity fluids: reappraisal of the role of current methods in the differential diagnosis of reactive versus malignant conditions

Cytologic examination of body fluids is commonly performed in the clinical laboratory. Determination of the presence of malignancy may sometimes be difficult. In this study, we prospectively studied 60 body fluids with a panel of antibodies, including MOC-31, epithelial membrane antigen, carcinoembryonic antigen, B72.3, keratin, desmin, and CA-125. DNA and S-phase studies were performed both by flow cytometry and image analysis. Thirty-seven fluids were classified as benign and 23 were classified as malignant. The sensitivity of the antibodies for identification of carcinoma in descending order of percentage detection rate were MOC-31 (95%), epithelial membrane antigen (93%), B72.3 (84%), and carcinoembryonic antigen (80%). Desmin stained mesothelial cells in all cases. CA-125 gave similar results but was less specific. Flow cytometry detected 14 of 20 malignant fluids and image analysis 17 of 23 by identifying an aneuploid population. Benign reactive mesothelial cells were not aneuploid. Tetraploidy due to reactive mesothelial cells was found in 9 of 37 body fluids. Their S-phase fraction was low (average, 3.2%). Tetraploidy in malignant cells was distinguished from the reactive mesothelial cells by high S-phase (average, 25.95). S-phase had some use as a discriminating factor, because no benign reactive cases had more than 17%. However, 7 of 23 malignant cases had a value below 17%. DNA analysis by image was more sensitive and specific than flow. Either may be used when immunocytochemistry is nondiagnostic or cannot be performed.

Heat-induced gene expression as a novel targeted cancer gene therapy strategy

One of the main advantages of gene therapy over traditional therapy is the potential to target the expression of therapeutic genes in desired cells or tissues. To achieve targeted gene expression, we experimented with a new approach based on the long-established phenomenon of the heat shock response. By using the green fluorescence protein as a reporter gene, it was demonstrated that expression of a heterologous gene with a heat shock protein 70 promoter could be elevated to 500-1000-fold over background by moderate hyperthermia (39 degrees C to 43 degrees C) in tissue cultured cells. The heat-induced green fluorescence protein expression was first detectable at 3 h after heating and reached a maximum at 18-24 h. The expression dropped back to baseline within 72 h. In addition, when cells were infected with adenovirus vectors containing the heat-inducible interleukin 12 or tumor necrosis factor alpha genes and then heated (42 degrees C, 30 min), expression was at least 13,600- or 6.8 x 10(5)-fold over background, respectively. Intralesion injection of the interleukin-12-carrying adenovirus vector in a mouse melanoma tumor model caused significant tumor growth delay only with hyperthermia treatment. Our results therefore support heat-induced gene expression as a feasible approach for targeted cancer gene therapy.

Preincisional dextromethorphan treatment for postoperative pain management after upper abdominal surgery

Previous studies showed that ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, provides a preemptive analgesic effect and preemptive analgesia improves postoperative pain management. The aim of this study was to examine whether premedication with dextromethorphan (DM) improves postoperative pain management after upper abdominal surgery. Sixty (American Society of Anesthesiologists class 1 and 2 of either gender) patients scheduled for upper abdominal surgery were included in the study. Patients were randomly assigned to one of four groups: control, DM-10, DM-20, and DM-40. In the control group, chlorpheniramine maleate (CPM, 20 mg) was injected immediately before induction of anesthesia intramuscularly (IM). In the DM-10, DM-20, and DM-40 groups, patients were premedicated with DM 10 mg, 20 mg, and 40 mg IM, respectively. After operation, patient-controlled analgesia (PCA) with morphine was given for pain relief. The time to the first PCA trigger, morphine consumption, pain scores, and analgesic-related side effects were recorded at 1, 2, 4, 24, 48, and 72 hours after surgery. The time to first PCA trigger for the control group was 17.8 +/- 1.4 minutes, for group DM-10 20.2 +/- 1.6 minutes, for group DM-20 32.4 +/- 1.9 minutes, and for DM-40 77.9 +/- 6.5 minutes. The morphine delivered and PCA triggering frequency were 5.5 +/- 0.5/11.3 +/- 0.8 times for the controls, 5.5 +/- 0.4/ 14.1 +/- 1.3 times for DM-10, 3.1 +/- 0.3/6.3 +/- 1.2 times for DM-20, and 0.2 +/- 0.1/0.3 +/- 0.2 times for DM-40 during the first hour after operation. For the first day, the figures are 19.9 +/- 1.2/23.9 +/- 1.4 for the controls, 15.6 +/- 1.2/17.3 +/- 2.4 for DM-10, 12.6 +/- 0.7/15.9 +/- 1.6 for DM-20, and 5.0 +/- 0.21/5.6 +/- 0.9 for DM-40. On the first day, the cough pain scores were 6.67 +/- 0.23, 6.53 +/- 0.16, 6.67 +/- 0.23, and 5.73 +/- 0.18 for the controls, DM-10, DM-20, and DM-40 groups, respectively. All data showed dose-dependent better pain relief in DM-premedicated patients. We conclude that DM premedication offers preemptive analgesia and reduces postoperative pain and morphine requirement.

von Willebrand factor is the most reliable immunohistochemical marker for megakaryocytes of myelodysplastic syndrome and chronic myeloproliferative disorders

To find the best immunohistochemical marker for megakaryocytes in normal marrow, myelodysplastic syndrome (MDS), and chronic myeloproliferative disorders (CMPD), 57 marrow biopsy specimens were studied semiquantitatively with immunohistochemical methods using a panel of 7 antibodies. The staining intensity was graded 0 to 3 for scoring 100 consecutive megakaryocytes in each stained section. The final score for each stain was the sum of these 100 megakaryocytes individually multiplied by their corresponding grade. In normal marrow (11 cases), the average scores for antivon Willebrand factor (vWF) and Ulex europaeus agglutinin-1 (UEA-1) were 177.1 and 195.1, respectively. The scores for the other 5 markers, including anti-platelet-derived growth factor-BB, 2 anti-transforming growth factor-beta 3, anti-CD61, and anti-CD79a ranged from 96.1 to 124.1. In MDS (27 cases), the scores were 200.8 (vWF), 152.6 (UEA-1), and 28.7 to 98.5 (others). In CMPD (19 cases), the scores were 220.5 (vWF), 179.2 (UAE-1), and 64.8 to 101.2 (others). These results show that vWF and UEA-1 are good immunohistochemical markers for megakaryocytes in normal marrow, and vWF is the best marker in MDS and CMPD. For routine practice, vWF is the most reliable marker for identifying atypical megakaryocytes, especially in the cases of 5q-syndrome and agnogenic myeloid metaplasia.

The agreement between self-reporting and clinical diagnosis for selected medical conditions among the elderly in Taiwan

A cross-sectional survey was conducted to consider whether there is agreement between self-report and clinical diagnosis in the prevalence of selected common chronic diseases among elderly Taiwanese. Between July 1992 and June 1993, both face-to-face interview and clinical evaluation were applied to a sample of 228 Taiwanese aged 65 y and older to estimate the prevalence of heart diseases, hypertension and diabetes. The results showed that a self-reported history of diabetes had the highest sensitivity (66. 7%) and specificity (95.2%). The self-report of heart diseases was the least sensitive (20.5%), while self-reports of hypertension was the least specific (82.8%). Multivariate analyses showed that age, education and number of self-reported diseases suffered from, appeared to influence the accuracy of the self reported data. Our data suggest a notable lack of agreement abetween self-report and clinical diagnosis for medical conditions, even for those with clear and unambiguous diagnostic criteria. The elderly in Taiwan tended to under report (with a consistently higher false negative rate than false positive rate) the existence of the three selected medical conditions. This was especially so for heart diseases. Our findings suggest that, if the level of disease prevalence in the population needs to be known for health planning estimates for hypertension and diabetes would not necessarily be a problem. However, the prevalence for heart disease would be seriously under-estimated. We also argue that information obtained by self-report should be validated before use, especially in the case of assessment of the prevalence of medical conditions in the elderly.

Initial stages of tumor cell-induced angiogenesis: evaluation via skin window chambers in rodent models

BACKGROUND

There is a paucity of information about events that follow immediately after tumor cells are triggered to initiate the process of angiogenesis (the formation of new blood vessels). Such information is relevant to the issue of when micrometastases vascularize and has implications for the accessibility of micrometastases to various treatments. In this study, we attempted to monitor events at the initiation of angiogenesis at the earliest possible stage of tumor growth in vivo.

METHODS

Two different rodent mammary tumor cell lines, R3230Ac from the Fischer 344 rat and 4T1 from the BALB/c mouse, were stably transfected with a gene that encodes an enhanced version of green fluorescence protein (GFP). GFP-labeled R3230Ac or 4T1 cells (about 20-50 cells) were implanted into dorsal skinfold window chambers of Fischer 344 rats or BALB/c mice, respectively. Tumor angiogenesis was then monitored serially and noninvasively for up to 4 weeks.

RESULTS

Clear evidence of modification of the host vasculature was observed when tumor mass reached approximately 60-80 cells, and functional new blood vessels were seen when tumor mass reached roughly 100-300 cells. Individual tumor cells exhibited a chemotaxis-like growth pattern toward the pre-existing host vasculature. When ex-flk1 (a soluble, truncated vascular endothelial cell growth factor receptor protein known to be antiangiogenic) was injected with the tumor cells, the initial angiogenic and tumor growth activities were inhibited considerably, indicating that angiogenesis inhibitors may halt tumor growth even before the onset of angiogenesis.

CONCLUSION

Angiogenesis induced by tumor cells after implantation in the host begins at a very early stage, i.e., when the tumor mass contains roughly 100-300 cells. Identification of chemotactic signals that initiate tumor cell migration toward the existing vasculature may provide valuable targets for preventing tumor progression and/or metastases.

Mechanism of inhibition of platelet aggregation by HCL-31D

The antiplatelet effect of the pyridazinone analogue, 4, 5-dihydro-6-[4-[2-hydroxy-3-(3,4 dimethoxybenzylamino)propoxy]naphth-1-yl]-3(2H)-pyridazinone (HCL-31D), was investigated in vitro with rabbit platelets. HCL-31D dose-dependently inhibited the platelet aggregation and ATP release induced by collagen (10 microg/ml), arachidonic acid (100 microM) or thrombin (0.1 U/ml) with an IC(50) of about 0.95-5.41 microM. HCL-31D (0.5-5 microM) increased the platelet cyclic AMP level in a dose-dependent manner. Furthermore, HCL-31D potentiated cyclic AMP formation caused by prostaglandin E(1) but not that caused by 3-isobutyl-1-methylxanthine (IBMX). HCL-31D also attenuated phosphoinositide breakdown and intracellular Ca(2+) elevation induced by collagen, arachidonic acid or thrombin. HCL-31D inhibited the formation of thromboxane B(2) induced by collagen or thrombin but not by arachidonic acid. In addition, HCL-31D did not affect platelet cylooxygenase and thromboxane synthase activity. These data indicate that HCL-31D is an inhibitor of phosphodiesterase and that its antiplatelet effect is mainly mediated by elevation of cyclic AMP levels.

[AFLP analysis of photoperiod-sensitive genic male sterile(PGMS) rice mutant lines]

The reaction conditions for rice AFLP assay were optimized. The relative efficiencies for polymorphism detection of RFLP, RAPD and AFLP were compared through the analysis between a pair of PGMS allelic mutant lines(NK58S and NK58F). Results indicated that the efficiency for polymorphism detection in rice is in the order of AFLP > RAPD > RFLP, and also indicated that AFLP is a powerful DNA molecular marker technique for polymorphism detection, especially in the cases of extremely low polymorphism, such as isogeneic lines and allelic mutant lines. The advantages and disadvantages of these three molecular marker systems were discussed. Using AFLP in conjunction with bulked segregating analysis, 5106 AFLP loci were screened and 9 of them showed polymorphism between NK58S and NK58F, 4 of the polymorphic AFLP products were cloned, Southern bloting analysis showed that two of them were single copy sequences while the other two were low copy sequences in rice genome.

[Experimental study on repair of peripheral nerve defect by basic fibroblast growth factor combined with autogenous vein graft conduit]

OBJECTIVE

To explore the effect of basic fibroblast growth factor (bFGF) combined with autogenous vein graft conduit on peripheral nerve regeneration.

METHODS

Fifty four New Zealand rabbits were divided into three groups. The main trunk of sciatic nerve of rabbit in one side was severed and bridged by autogenous vein. 0.2 ml bFGF solution (4,000 U/ml) was intravenously injected to the vein graft conduit as group A, the same amount of saline solution as group B, and no solution injection as group C. Microscopic examination, axon video analysis and nerve conduct velocity were performed at the 10th, 30th, and 100th day after operation.

RESULTS

The nerve fibers were grown into vein graft conduit in all groups at 30th after operation, they were more and regular in group A than that of group B and C, and the axon regeneration rate in group A was more than that of group B and C.

CONCLUSION

bFGF combined with autogenous vein graft conduit can markedly promote nerve regeneration.

Immunophenotypic analysis of peripheral blood and bone marrow in the staging of B-cell malignant lymphoma

This study evaluated the contributing roles of flow cytometric immunophenotyping of blood and bone marrow and immunohistochemical paraffin section staining of bone marrow biopsies in the staging of B-cell malignant lymphoma. Flow immunophenotyping was performed on a marrow specimen in 175 cases; a corresponding blood specimen was also immunophenotyped in 135 of these cases. Morphologic marrow involvement by lymphoma was found in 59 cases; flow immunophenotyping identified 54 cases with a monoclonal B-cell process: morphology-positive/flow-positive (n = 49), morphology-positive/flow-negative (n = 10), morphology-negative/flow-positive (n = 5), and morphology-negative/flow-negative (n = 111). The 10 morphology-positive/flow-negative cases included 5 follicular and 5 large-cell lymphomas with minimal marrow involvement. All 5 morphology-negative/flow-positive cases were from patients with large-cell lymphomas and bulky clinical disease. Because the blood contained the same B-cell clone in 2 of 2 morphology-negative/flow-positive cases studied, blood contamination of marrow may account for these findings. Blood flow cytometric immunophenotyping studies were positive in 32 cases; 30 had marrow involvement by morphology and were from patients with follicular, mantle cell, lymphoplasmacytic, small lymphocytic, or marginal zone lymphomas. From our results, we conclude that (1) bone marrow flow cytometric immunophenotyping is not a cost-effective replacement for good morphologic evaluation in lymphoma staging and that (2) a positive peripheral blood flow cytometric immunophenotyping study when performed in low-grade lymphomas correlates with marrow involvement.

Antiplatelet effect of amlodipine: a possible mechanism through a nitric oxide-mediated process

The effect of amlodipine, a novel calcium channel blocker of the dihydropyridine type, on rabbit platelet aggregation, and the possible antiaggregatory mechanisms of amlodipine, especially on the nitric oxide (NO) guanosine 3',5'-cyclic monophosphate (cyclic GMP)-mediated pathway, were investigated. Other effects of amlodipine on thromboxane B2 (TXB2) formation in platelets also were examined. Amlodipine concentration-dependently inhibited rabbit platelet aggregation induced by collagen (10 microg/mL) or thrombin (0.1 U/mL) with an IC50 range of 32-69 microM. Along with this inhibition, our results also demonstrated that in the presence of L-arginine (100 IM), amlodipine (50 microM) increased nitric oxide synthetase (NOS) activity (from the resting activity of 2.05+/-0.36 to 7.11+/-0.95 pmol/mg protein/min) and NO release (by 80%), accompanied by an elevation of the cyclic GMP level (from the resting platelet level of 1.27+/-0.12 to 6.21+/-0.55 pmol/10(9) platelets) induced by collagen (10 microg/mL). However, the antiaggregatory effect of amlodipine (50 microM) could be attenuated significantly by oxyhemoglobin (5 microM), a NO scavenger, or N(G)-nitro-L-arginine methyl ester (100 microM), a specific NOS inhibitor. In addition, the TXB2 production in platelets induced by collagen or thrombin was concentration-dependently inhibited by amlodipine. Therefore, we propose that the antiaggregatory mechanisms of amlodipine might be mediated, in part, by a NO-cyclic GMP process accompanied by the inhibition of TXB2 formation in platelets.

Inhibitory mechanisms of dantrolene on platelet aggregation

The antiplatelet effect of dantrolene and possible inhibitory mechanisms were studied in rabbit platelets. Preincubation of rabbit washed platelets with dantrolene (50-300 microM) inhibited the platelet aggregation and adenosine triphosphate release induced by arachidonic acid (100 microM), collagen (10 microg/mL), or thrombin (0.1 U/mL) in a dose-dependent manner. The thromboxane B2 formation caused by collagen or thrombin was inhibited by dantrolene, while formation of thromboxane B2 and prostaglandin D2 induced by arachidonic acid were not inhibited. In addition, the formation of phosphoinositide breakdown and the rise of intracellular calcium level induced by collagen or thrombin were also inhibited in a dose-dependent manner by dantrolene in the presence of indomethacin (2 microM). However, the platelets cyclic AMP level was not affected by dantrolene. In conclusion, the present study demonstrates that dantrolene inhibits platelet activation mainly due to suppression of phosphoinositide breakdown.

Epicardial ST depression in acute myocardial infarction

The presence of electrocardiographic ST depression in acute infarction remains controversial and poorly explained. A combined animal and modeling study was performed to evaluate the source of ST changes in acute infarction. In anaesthetized sheep, small infarcts showed uniform ST elevation over the infarction whereas larger infarcts showed marked ST depression over the normal myocardium in addition to the ST elevation. These findings were replicated by bidomain models of the heart. A hollow sphere was used to model a gradually increasing infarct, and this showed that there was a decrease in the ratio of ST elevation to ST depression as the infarct was increased. The current flowing out of the heart must be identical to the current flowing back into the heart. This means that any infarction will produce ST depression as well as ST elevation, the ratio between the two being related to the size of the infarction. Small infarction is associated with a small region of ST elevation and minor ST depression of the remaining myocardium, and as the infarct region increases, the amplitude of the epicardial ST elevation falls and the amplitude of the ST depression increases. Infarction size is proportional to both the height of the ST depression on the epicardium and the strength of the epicardial ST segment dipole.