Measurement of the bioactivity of interleukin and tumour necrosis factor in synovial fluid of Kashin-Beck disease

We studied the bioactivity of interleukin (IL-1) and tumour necrosis factor (TNF) in the synovial fluid of 12 patients with Kashin-Beck disease (KBD), 8 patients with osteoarthritis (OA) and 8 normal controls. C57 female mouse T cell proliferation method was used to test the bioactivity of IL-1, and lethality method with L929 cells to test the bioactivity of TNF. The bioactivities of IL-1 and TNF in the synovial fluid from patients with KBD were higher than those in the synovial fluid of osteoarthritis and normal controls, indicating the participation of IL-1 and TNF in the pathogenesis of KBD.

Phase I Study of Hepatic Arterial Infusion of Floxuridine and Dexamethasone With Systemic Irinotecan for Unresectable Hepatic Metastases From Colorectal Cancer

PURPOSE: To determine the maximum-tolerated dose (MTD) and dose-limiting toxicities of concurrent systemic irinotecan and hepatic arterial infusion (HAI) of floxuridine (FUDR) and dexamethasone in patients with unresectable hepatic metastases from colorectal cancer, to determine the safety of this combination in patients who have undergone cryosurgery, and to evaluate the pharmacokinetic effects of HAI FUDR on the metabolism of irinotecan.

PATIENTS AND METHODS: Forty-six previously treated patients with unresectable liver metastases and no known extrahepatic disease were treated concurrently with intravenous irinotecan weekly for 3 weeks and with HAI of FUDR and dexamethasone for 14 days (both were recycled in 28 days). Parallel cohorts of patients treated with or without cryosurgery were entered at escalating dose levels.

RESULTS: The MTD for patients who did not undergo cryosurgery was 100 mg/m2 of irinotecan weekly for 3 weeks every 4 weeks with concurrent HAI FUDR (0.16 mg/kg/d × pump volume/flow rate) plus dexamethasone for 14 days of a 28-day cycle. The dose-limiting toxicities were diarrhea and neutropenia. The response rate (complete and partial) among all patients who did not undergo cryosurgery was 74%. All patients in the cryosurgery group responded, and seven of the eight cryosurgery patients developed normal positron emission tomography scans after chemotherapy. HAI FUDR had no effect on the metabolism of irinotecan.

CONCLUSION: Combination therapy with HAI FUDR and dexamethasone plus systemic irinotecan may be safely administered to patients with unresectable hepatic metastases from colorectal cancer. The MTD has been reached for patients with unresectable disease, and we continue to investigate the MTD for patients who have undergone cryosurgery. Although the main objective of this study was to evaluate the toxicity of the combined regimen, a high response rate (74%) was observed.

Phase II study of the cyclin-dependent kinase inhibitor flavopiridol administered to patients with advanced gastric carcinoma

PURPOSE

Flavopiridol is the first cyclin-dependent kinase inhibitor to enter clinical trials. Activity in gastric cancer xenografts and in a patient with gastric cancer on the phase I trial led to this phase II study of flavopiridol in patients with metastatic gastric cancer.

PATIENTS AND METHODS

Sixteen patients were entered onto the study, and 14 were assessable for response. Flavopiridol was administered initially at a dose of 50 mg/m(2)/d by continuous infusion for 72 hours every 2 weeks. Assessment of plasma pharmacokinetics was performed in all patients. Peripheral mononuclear cells were collected throughout the 72-hour infusion for determinants of apoptosis.

RESULTS

There were no major objective responses (exact confidence interval 0% to 23%). One patient achieved a minor response in his liver metastases, though the primary progressed. Other patients exhibited histologic and radiographic evidence of tumor necrosis. Common toxicities included fatigue in 93% of patients (grade 3 or 4 in 27%) and diarrhea in 73% of patients (grade 3 or 4 in 20%). Five patients (33%) developed venous thromboses at the central catheter tip. The studies performed on peripheral mononuclear cells indicated no induction of apoptosis.

CONCLUSION

Flavopiridol administered as a single agent for 72 hours every 14 days is inactive in the treatment of gastric cancer. The drug also induced an unexpected higher incidence of vascular thrombosis and fatigue than was anticipated from the phase I trials. Future development of flavopiridol will depend on other doses and schedules in combination with chemotherapy.

Structure-activity relationships for a large diverse set of natural, synthetic, and environmental estrogens

Understanding structural requirements for a chemical to exhibit estrogen receptor (ER) binding has been important in various fields. This knowledge has been directly and indirectly applied to design drugs for human estrogen replacement therapy, and to identify estrogenic endocrine disruptors. This paper reports structure-activity relationships (SARs) based on a total of 230 chemicals, including both natural and xenoestrogens. Activities were generated using a validated ER competitive binding assay, which covers a 10(6)-fold range. This study is focused on identification of structural commonalities among diverse ER ligands. It provides an overall picture of how xenoestrogens structurally resemble endogenous 17beta-estradiol (E(2)) and the synthetic estrogen diethylstilbestrol (DES). On the basis of SAR analysis, five distinguishing criteria were found to be essential for xenoestrogen activity, using E(2) as a template: (1) H-bonding ability of the phenolic ring mimicking the 3-OH, (2) H-bond donor mimicking the17beta-OH and O-O distance between 3- and 17beta-OH, (3) precise steric hydrophobic centers mimicking steric 7alpha- and 11beta-substituents, (4) hydrophobicity, and (5) a ring structure. The 3-position H-bonding ability of phenols is a significant requirement for ER binding. This contributes as both a H-bond donor and acceptor, although predominantly as a donor. However, the 17beta-OH contributes as a H-bond donor only. The precise space (the size and orientation) of steric hydrophobic bulk groups is as important as a 17beta-OH. Where a direct comparison can be made, strong estrogens tend to be more hydrophobic. A rigid ring structure favors ER binding. The knowledge derived from this study is rationalized into a set of hierarchical rules that will be useful in guidance for identification of potential estrogens.

Inhaled aerosolization of all-trans-retinoic acid for targeted pulmonary delivery

Retinoids have shown promising activity for both cancer chemoprevention and as a treatment for emphysema. However, chronic oral administration of these drugs is limited by systemic side effects, including hepatic dysfunction, skeletal malformations, hyperlipidemia. hypercalcemia, and other reactions. In order to improve the pulmonary targeting of this potentially useful therapy, we developed a system for aerosolization of retinoids that substantially increased their local bioavailability. We compared the biodistribution and pharmacokinetics of an inhaled formulation of all-trans-retinoic acid (all-trans-RA), which was packaged in a metered dose inhaler, following both intratracheal (IT) and intravenous (IV) administration in male Sprague-Dawley rats. After drug administration, anesthetized animals were killed at 5 min, and at 1, 2, 4, 6 and 24 h. Plasma and emulsified samples of liver and lung tissues were dissected, extracted, and frozen prior to measurement of all-trans-RA concentration by high-performance liquid chromatography (HPLC). Aerosolization and IT injection of all-trans-RA resulted in a significantly longer pulmonary half-life of the drug (both 5-17 h), lower peak serum concentrations (aerosol 71 +/- 31 ng/ml, IT 68 +/- 50 ng/ml), and lower liver levels (aerosol 111 +/- 28 ng/g, IT 753 +/- 350 ng/g) than the same dose administered IV (2 h, 838 +/- 56 ng/ml, 4,258 +/- 1,006 ng/g, respectively; P < 0.05 for each comparison). Histologic examination of lungs and trachea showed no focal irritation attributable to the drug after single-dose administration. These results suggest that aerosolization of retinoids may offer a practical alternative to systemic oral administration for chemoprevention trials or treatment of lung diseases. This method may substantially increase the therapeutic index of these compounds by reducing systemic complications associated with long-term dosing.

Genetic evidence for the interactions of cyclin D1 and p27(Kip1) in mice

The cell cycle of cultured cells appears to be regulated by opposing actions of the cyclins together with their partners, the cyclin-dependent kinases (Cdk), and their inhibitors (Cki). Consistent with this situation null mutations in the genes for cyclin D1 and Cki p27(Kip1) in mice give opposite phenotypes of dwarfism and gigantism. To test their genetic interactions, we generated mice nullizygous for both genes. Correction of cyclin D1 or p27 null to wild-type phenotypes was observed for many but not all traits. These included, for cyclin D1(-/-) mice, body weight, early lethality, retinal hypoplasia, and male aggressiveness and, for p27(-/-) mice, body weight, retinal hyperplasia, and embryo implantation. p27(-/-) traits that were not corrected were the aberrant estrus cycles, luteal cell proliferation, and susceptibility to pituitary tumors. This mutual correction of these phenotypes is the first genetic demonstration of the interaction of these inhibitory and stimulatory cell cycle-regulatory molecules in vivo. The molecular basis for the correction was analyzed in the neonatal retina. Retinal cellularity was rescued in the cyclin D1 null mouse by loss of p27 with only a partial restoration of phosphorylation of retinoblastoma protein (Rb) and Cdk4 activity but with a dramatic elevation of Cdk2 activity. Our data provide in vivo genetic validation of cell culture experiments that indicated that p27 acts as a negative regulator of cyclin E-Cdk2 activity and that it can be titrated away by cyclin D-Cdk4 complexes. It also supports the suggestion that the cyclin E/Cdk2 pathway can largely bypass Rb in regulating the cell cycle in vivo.

Sugar coordinately and differentially regulates growth- and stress-related gene expression via a complex signal transduction network and multiple control mechanisms

In plants, sugars are required to sustain growth and regulate gene expression. A large set of genes are either up- or down-regulated by sugars; however, whether there is a common mechanism and signal transduction pathway for differential and coordinated sugar regulation remain unclear. In the present study, the rice (Oryza sativa cv Tainan 5) cell culture was used as a model system to address this question. Sucrose and glucose both played dual functions in gene regulation as exemplified by the up-regulation of growth-related genes and down-regulation of stress-related genes. Sugar coordinately but differentially activated or repressed gene expression, and nuclear run-on transcription and mRNA half-life analyses revealed regulation of both the transcription rate and mRNA stability. Although coordinately regulated by sugars, these growth- and stress-related genes were up-regulated or down-regulated through hexokinase-dependent and/or hexokinase-independent pathways. We also found that the sugar signal transduction pathway may overlap the glycolytic pathway for gene repression. alpha-Amylase and the stress-related genes identified in this study were coordinately expressed under sugar starvation, suggesting a convergence of the nutritional and environmental stress signal transduction pathways. Together, our studies provide a new insight into the complex signal transduction network and mechanisms of sugar regulation of growth and stress-related genes in plants.

Paclitaxel, estramustine phosphate, and carboplatin in patients with advanced prostate cancer

PURPOSE

To determine the safety and activity of weekly paclitaxel in combination with estramustine and carboplatin (TEC) in patients with advanced prostate cancer.

PATIENTS AND METHODS

In a dose-escalation study, patients with advanced prostate cancer were administered paclitaxel (weekly 1-hour infusions of 60 to 100 mg/m(2)), oral estramustine (10 mg/kg), and carboplatin (area under the curve, 6 mg/mL-min every 4 weeks). Paclitaxel levels were determined 0, 30, 60, 90, and 120 minutes and 18 hours after infusion, and a concentration-time curve was estimated. Once a safe dose was established, a multi-institutional phase II trial was conducted in patients with progressive androgen-independent disease.

RESULTS

Fifty-six patients with progressive androgen-independent disease were treated for a median of four cycles. The dose of paclitaxel was escalated from 60 to 100 mg/m(2) without the occurrence of DLT. Posttherapy decreases in serum prostate-specific antigen levels of 50%, 80%, and 90% were seen in 67%, 48%, and 39% (95% confidence interval, 55% to 79%, 35% to 61%, 26% to 52%) of the patients, respectively. Of the 33 patients with measurable disease, two (6%) had a complete response and 13 (39%) had a partial response. The overall median time to progression was 21 weeks, and the median survival time for all patients was 19.9 months. Major grade 3 or 4 adverse effects were thromboembolic disease (in 25% of patients), hyperglycemia (in 38%), and hypophosphatemia (in 42%). Significant leukopenia, thrombocytopenia, and peripheral neuropathy were not observed.

CONCLUSION

TEC has significant antitumor activity and is well tolerated in patients with progressive androgen-independent prostate cancer.

QSAR models using a large diverse set of estrogens

Endocrine disruptors (EDs) have a variety of adverse effects in humans and animals. About 58,000 chemicals, most having little safety data, must be tested in a group of tiered assays. As assays will take years, it is important to develop rapid methods to help in priority setting. For application to large data sets, we have developed an integrated system that contains sequential four phases to predict the ability of chemicals to bind to the estrogen receptor (ER), a prevalent mechanism for estrogenic EDs. Here we report the results of evaluating two types of QSAR models for inclusion in phase III to quantitatively predict chemical binding to the ER. Our data set for the relative binding affinities (RBAs) to the ER consists of 130 chemicals covering a wide range of structural diversity and a 6 orders of magnitude spread of RBAs. CoMFA and HQSAR models were constructed and compared for performance. The CoMFA model had a r2 = 0.91 and a q2LOO = 0.66. HQSAR showed reduced performance compared to CoMFA with r2 = 0.76 and q2LOO = 0.59. A number of parameters were examined to improve the CoMFA model. Of these, a phenol indicator increased the q2LOO to 0.71. When up to 50% of the chemicals were left out in the leave-N-out cross-validation, the q2 remained significant. Finally, the models were tested by using two test sets; the q2pred for these were 0.71 and 0.62, a significant result which demonstrates the utility of the CoMFA model for predicting the RBAs of chemicals not included in the training set. If used in conjunction with phases I and II, which reduced the size of the data set dramatically by eliminating most inactive chemicals, the current CoMFA model (phase III) can be used to predict the RBA of chemicals with sufficient accuracy and to provide quantitative information for priority setting.

Fragmentation of N-oxides (deoxygenation) in atmospheric pressure ionization: investigation of the activation process

The diagnostic fragmentation of N-oxides resulting from loss of the oxygen atom (MH+ --> MH+-O) in electrospray and atmospheric pressure chemical ionization (APCI) mass spectra was investigated. When the temperature of the heated capillary tube was elevated, the ratio of the intensity of the [MH+ -16] fragment to the precursor ion (MH+) increased. This 'deoxygenation' process was associated with thermal activation and did not result from collisional activation in the desolvation region of the API source. Although the extent of 'deoxygenation' is compound-dependent, it can provide evidence for the presence of an N-oxide in a sample and can be used to distinguish N-oxides from hydroxylated metabolites (Ramanathan et al. Anal. Chem. 2000; 72: 1352). To demonstrate the practical application of thermal fragmentation of N-oxides, liquid chromatography (LC)/APCI-MS was used to distinguish an N-oxide drug from its hydroxylated metabolite in an unprocessed rat urine sample, despite the fact that the drug and its metabolite were not fully resolved by HPLC.

Huanglian, A chinese herbal extract, inhibits cell growth by suppressing the expression of cyclin B1 and inhibiting CDC2 kinase activity in human cancer cells

Huanglian is an herb that is widely used in China for the treatment of gastroenteritis. We elected to determine whether huanglian could inhibit tumor cell growth by modulating molecular events directly associated with the cell cycle. Huanglian inhibited tumor growth and colony formation of gastric, colon, and breast cancer cell lines in a time- and dose-dependent manner. Cell growth was completely inhibited after 3 days of continuous drug exposure to 10 microg/ml of herb. This degree of growth inhibition was significantly greater than that observed with berberine, the major constituent of the herb. The inhibition of cell growth by huanglian was associated with up to 8-fold suppression of cyclin B1 protein. This resulted in complete inhibition of cdc2 kinase activity and accumulation of cells in G(2). The mRNA expression of cyclin B1 was not changed after huanglian treatment. There was no change in the protein expression of cyclins A or E. Therefore, the effect of huanglian on inhibiting tumor growth seems to be mediated by the selective suppression of cyclin B1, which results in the inhibition of cdc2 kinase activity. Inhibition of cyclin dependent kinase (cdk) activity is emerging as an attractive target for cancer chemotherapy. Huanglian represents a class of agents that can inhibit tumor cell growth by directly suppressing the expression of a cyclin subunit that is critical for cell cycle progression. These results indicate that traditional Chinese herbs may represent a new source of agents designed for selective inhibition of cyclin dependent kinases in cancer therapy.

Rationalised prescribing for community acquired pneumonia: a closed loop audit

AIMS

To audit the management of community acquired pneumonia before and after the introduction of a protocol. To determine the aetiology of pneumonia using routine investigations and polymerase chain reaction (PCR).

METHODS

Retrospective and prospective audit following the introduction of a management protocol. Prospective cases were investigated routinely and with PCR on blood and nasopharyngeal aspirate.

RESULTS

There was a significant increase in rational prescribing following introduction of the protocol with 75% of children receiving intravenous penicillin or erythromycin compared with 26% beforehand. Of 89 children in the prospective group, 51 microbiological diagnoses were achieved in 48 children. Seven children had Streptococcus pneumoniae infection, 14 had Mycoplasma infection, six had pertussis, and one had Chlamydia pneumoniae infection. Twenty three children had a viral cause of which respiratory syncytial virus was commonest.

CONCLUSIONS

Introduction of the protocol led to improved prescribing. PCR increased the diagnostic yield and the results support the management protocol.

Heat shock proteins' mRNA expression in asthma

OBJECTIVE

The aim of the present study was to investigate the expression levels of heat shock proteins (HSP) mRNA in the peripheral blood mononuclear cells (PBMC) of patients with asthma and chronic bronchitis to elucidate the role of HSP in the pathogenesis of asthma and chronic bronchitis.

METHOD

Using reverse transcription-DNA polymerase chain reaction, the expression levels of HSP70, HSP90alpha and HSP90beta genes in PBMC in normal state and after heat shock were investigated.

RESULTS

No HSP70 gene but HSP90alpha and HSP90beta expressions were found in non-heat-shocked PBMC of normal controls; HSP90alpha and HSP90beta genes may be expressed in PBMC of all patients, independently of acute episodes. Expression of HSP70 was found in PBMC of asthmatic patients in acute episodes and three symptom-free patients with Aas 3, step 2. Among patients with chronic bronchitis, no HSP70 gene expression was found in PBMC of patients in convalescent period but in PBMC of patients in acute episode. HSP90alpha and HSP90beta genes were expressed in PBMC of both patient groups. After heat shock, expressions of the three genes increased significantly in PBMC of both normal controls and patients.

CONCLUSION

Expression of HSP70 gene in PBMC of asthmatic and chronic bronchitis patients was different, indicating that HSP, especially HSP70, might be involved in the pathogenesis of asthma.

Phase I and pharmacokinetic study of 10-propargyl-10-deazaaminopterin, a new antifolate

The 10-deazaaminopterins are a new class of rationally designed antifolates demonstrating greater antitumor effects than methotrexate in murine tumor models and human tumor xenografts. Their design was aimed at improving membrane transport and polyglutamylation in tumor cells, resulting in increased intracellular accumulation and enhanced cytotoxicity. Compared with other 4-aminofolate analogues, 10-propargyl-10-deazaaminopterin (PDX) is the most efficient permeant for the RFC-1-mediated internalization and substrate for folylpolyglutamate synthetase. PDX demonstrates greater in vitro and in vivo antitumor efficacy than methotrexate or edatrexate. We undertook a Phase I study with PDX to identify the potential toxicities and define an optimal dose and schedule. Thirty-three patients were enrolled, all of whom had non-small cell lung cancer (NSCLC) and were treated previously with a median of two prior chemotherapy regimens. Initially, PDX was administered weekly for 3 weeks in a 4-week cycle. Mucositis requiring dose reduction and/or delay in the first cycle occurred in four of six patients treated at the initial dose level (30 mg/m2), making this the maximal tolerated dose for PDX given on this schedule. The treatment schedule was then modified to every 2 weeks. Twenty-seven patients were treated twice weekly with a total of 102 four-week cycles (median, 2 cycles/patient). Mucositis was the dose-limiting toxicity, with grade 3 and 4 mucositis occurring in the first two patients treated at the 170 mg/m2 dose level. Other toxicities were mild and reversible. No neutropenia was observed. The recommended Phase II dose is 150 mg/m2 biweekly. At that dose level, the mean area under the curve was 20.6 micromol x h, and the mean terminal half-life was 8 h. Two patients with stage IV NSCLC had major objective responses, and five patients had stable disease for 7 (two patients), 9 (one patient), 10 (one patient), and 13 months (one patient). PDX is a new antifolate with manageable toxicity and evidence of antitumor activity in NSCLC. A Phase II trial in NSCLC and a Phase I trial with paclitaxel are under way. These studies will also quantitate the expression of genes controlling internalization (RFC-1) and polyglutamylation of PDX in tumor cells as correlates of response.

Quantitative comparisons of in vitro assays for estrogenic activities

Substances that may act as estrogens show a broad chemical structural diversity. To thoroughly address the question of possible adverse estrogenic effects, reliable methods are needed to detect and identify the chemicals of these diverse structural classes. We compared three assays--in vitro estrogen receptor competitive binding assays (ER binding assays), yeast-based reporter gene assays (yeast assays), and the MCF-7 cell proliferation assay (E-SCREEN assay)--to determine their quantitative agreement in identifying structurally diverse estrogens. We examined assay performance for relative sensitivity, detection of active/inactive chemicals, and estrogen/antiestrogen activities. In this examination, we combined individual data sets in a specific, quantitative data mining exercise. Data sets for at least 29 chemicals from five laboratories were analyzed pair-wise by X-Y plots. The ER binding assay was a good predictor for the other two assay results when the antiestrogens were excluded (r(2) is 0.78 for the yeast assays and 0.85 for the E-SCREEN assays). Additionally, the examination strongly suggests that biologic information that is not apparent from any of the individual assays can be discovered by quantitative pair-wise comparisons among assays. Antiestrogens are identified as outliers in the ER binding/yeast assay, while complete antagonists are identified in the ER binding and E-SCREEN assays. Furthermore, the presence of outliers may be explained by different mechanisms that induce an endocrine response, different impurities in different batches of chemicals, different species sensitivity, or limitations of the assay techniques. Although these assays involve different levels of biologic complexity, the major conclusion is that they generally provided consistent information in quantitatively determining estrogenic activity for the five data sets examined. The results should provide guidance for expanded data mining examinations and the selection of appropriate assays to screen estrogenic endocrine disruptors.

[A preliminary study of viral cross-transmission in dentistry]

OBJECTIVE

To research the viral cross-transmission of a DNA virus (HBV) and a RNA virus (HCV) in dentistry.

METHODS

Five plans were designed to sterilize the oral instruments that had been infected with HBV or HCV positive serum. HBsAg, HBV-DNA, anti-HCV, HCV-RNA were detected before and after sterilization.

RESULTS

All methods could effectively clean the specific proteins (HBsAg/anti-HCV) and nucleic acids (HBV-DNA/HCV-RNA) of the infected virus.

CONCLUSION

The instruments which have been sterilized should not be the main way of the cross-transmission of virus in dentistry.

[Persistence of hepatitis C virus type II in patient's peripheral blood B lymphocytes transformed by Epstein-Barr virus]

OBJECTIVE

To study the persistence and replication of hepatitis C virus (HCV)-RNA in human peripheral blood B cells transformed by Epstein-Barr virus (EBV) and cultured in vitro.

METHODS

EBV was used for infecting B lymphocytes from one hepatitis C patient with HCV positive in the peripheral blood mononuclear cells (PBMC) and transforming them into lymphoblasts capable of being propagated indefinitely. Then, HCV RNA of the cultured cells and supernatants was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) every one month. HCV gene was typed by enzyme separating method. Electron microscopy and immunoelectron microscopy were employed to locate HCV in the cells and observe the character of its configuration.

RESULTS

HCV positive-strand RNA was detected in the cultured cells for 1 year. Interestingly, the HCV positive-strand RNA was identified in supernatants and the negative-strand RNA was also observed in the cultured cells intermittently. HCV gene was type II. Electron microscopy observed HCV spherical virus-like particles with a diameter of approximately 45 nm to 70 nm, individual particles 110 nm, in the LCL cytoplasmic vesicles.

CONCLUSION

HCV may exist in the cultured cell line for a longer period and reproduce in and secrete out of them. HCV locates mainly in the cytoplasm. The cell line might be useful in analyzing the mechanisms of HCV persistence in PBMC.

The estrogen receptor relative binding affinities of 188 natural and xenochemicals: structural diversity of ligands

We have utilized a validated (standardized) estrogen receptor (ER) competitive-binding assay to determine the ER affinity for a large, structurally diverse group of chemicals. Uteri from ovariectomized Sprague-Dawley rats were the ER source for the competitive-binding assay. Initially, test chemicals were screened at high concentrations to determine whether a chemical competed with [3H]-estradiol for the ER. Test chemicals that exhibited affinity for the ER in the first tier were subsequently assayed using a wide range of concentrations to characterize the binding curve and to determine each chemical's IC50 and relative binding affinity (RBA) values. Overall, we assayed 188 chemicals, covering a 1 x 10(6)-fold range of RBAs from several different chemical or use categories, including steroidal estrogens, synthetic estrogens, antiestrogens, other miscellaneous steroids, alkylphenols, diphenyl derivatives, organochlorines, pesticides, alkylhydroxybenzoate preservatives (parabens), phthalates, benzophenone compounds, and a number of other miscellaneous chemicals. Of the 188 chemicals tested, 100 bound to the ER while 88 were non-binders. Included in the 100 chemicals that bound to the ER were 4-benzyloxyphenol, 2,4-dihydroxybenzophenone, and 2,2'-methylenebis(4-chlorophenol), compounds that have not been shown previously to bind the ER. It was also evident that certain structural features, such as an overall ring structure, were important for ER binding. The current study provides the most structurally diverse ER RBA data set with the widest range of RBA values published to date.

[Characteristic immunodeficiency syndrome of rapid fatal type of simian immunodeficiency virus infected monkeys]

OBJECTIVE

To observe the characteristic immunodeficiency syndrome of the rapid fatal type of simian immunodeficiency virus (SIV) infected monkeys.

METHODS

Eighty rhesus monkeys and 4 cynomolgus monkeys were intravenously inoculated with SIVmac or SIVmac251. The virus isolation and viral titer, estimation by indirect immunofluroresence and viral antibody were determined periodically from monkeys' plasma; lymph node biopsies were performed for pathohistological examination.

RESULTS

Twelve out of 84 macaque (14.2%) died of rapid progressive type after inoculation of SIVmac and SIVmac251 in the duration 3 to 4 months. Dying monkeys showed persistent high viremia and low level titre antibody. Eight of 10 pathohistological changes showed severe depletion of lymphoid tissue in spleen and lymph nodes, there were remarkable immunodeficiency with opportunity infection. The other two monkeys appeared moderate lymphoid tissue deletion and hyperplasia without opportunity infections. The survived monkeys' (72/84) lymph nodes biopsies revealed hypoplasia of lymphoid tissue.

CONCLUSIONS

The characteristic immunodeficiency syndrome of rapid fatal type of simian immunodeficiency virus infected monkeys could be made with persistent high viremia, low level antibody, severe lymphoid tissue deletion in lymph nodes and spleen, as well as complicated opportunity infections.

Predicted changes in pre-mRNA secondary structure vary in their association with exon skipping for mutations in exons 2, 4, and 8 of the Hprt gene and exon 51 of the fibrillin gene

Exon skipping that accompanies exonic mutation might be caused by an effect of the mutation on pre-mRNA secondary structure. Previous attempts to associate predicted secondary structure of pre-mRNA with exon skipping have been hindered by either a small number of available mutations, sub-optimal structures, or weak effects on exon skipping. This report identifies more extensive sets of mutations from the human and hamster Hprt gene whose association with exon skipping is clear. Optimal secondary structures of the wild-type and mutant pre-mRNA surrounding each exon were predicted by energy minimization and were compared by energy dot plots. A significant association was found between the occurrence of exon skipping and the disruption of a stem containing the acceptor site consensus sequences of exon 8 of the human Hprt gene. However, no change in secondary structure was associated with skipping of exon 4 of the hamster Hprt gene. Using updated energy parameters we found a different structure than that previously reported for exon 2 of the hamster Hprt gene. In contrast to the previously reported structure, no significant association was found between predicted structural changes and skipping of exon 2. For all three Hprt exons studied, there was a significantly greater number of deoxythymidine substitutions among mutations accompanied by exon skipping than among mutations without exon skipping. For exon 8, deoxythymidine substitution was also associated with structural changes in the stem containing the acceptor site consensus sequences. For exon 51 of the human fibrillin gene, structural differences from wild type were predicted for all four mutations accompanied by exon skipping that were not were predicted for a single mutation without exon skipping. Our results suggest that both primary and secondary pre-mRNA structure contribute to definition of Hprt exons, which may involve exonic splicing enhancers.

Heat shock proteins mRNA expressions by peripheral blood mononuclear cells in asthma and chronic bronchitis

OBJECTIVE

To investigate the manifestations that heat shock proteins(HSPs) possess in the pathogenesis of asthma and chronic bronchitis.

METHODS

Using reverse transcription-DNA polymerase chain reaction (RT-PCR), we investigated the expression levels of HSP70, HSP90 alpha and HSP90 beta genes in peripheral blood mononuclear cells(PBMC) at natural state and after heat shock in 14 healthy volunteers, 21 patients with asthma and 18 patients with chronic bronchitis.

RESULTS

No HSP70 gene but HSP90 alpha and HSP90 beta expressions were found in non-heat-shocked PBMC of normal control; HSP90 alpha and HSP90 beta genes may be expressed in PBMC of patients no matter whether they were in acute episode or not. Expression of HSP70 was found in PBMC of patients in acute episodes and of three symptoms-free patients with Aas 3, step 2. No expression of HSP70 gene was found in PBMC of patients in convalescent period but in PBMC of patients in acute episode. HSP90 alpha and HSP90 beta genes were expressed in PBMC of the two patients groups; After heat shock, expressions of the three genes increased in amount significantly in PBMC of all normal controls and patients.

CONCLUSION

Expression of HSP70 gene in PBMC of asthmatic patients and chronic bronchitis was different, indicating that HSPs, especially HSP70 might be involved in the pathogenesis of asthma.

[Study on the antitumor effect of angiostatin on LA795 adenocarcinoma cells]

OBJECTIVE

To study the antitumor effect of angiostatin on LA795 adenocarcinoma cells inoculated on T739 mice.

METHODS

Affinity chromatography purified plasminogen was digested by pancreatic elastase and angiostatin was obtained by purifying the digestion with affinity chromatography and dialysis. T739 mice were inoculated with LA795 cells. Angiostatin was given to part of inoculated and uninoculated mice by intraperitoneal injection fourteen days after the inoculation. The treatment lasted 20 days and the size of tumor, survival period, behavior of the mice and pathology of lungs, livers and kidneys were observed.

RESULTS

The size of tumor decreased from (2.35 +/- 0.26) cm to (0.97 +/- 0.34) cm after angiostatin treatment. The number of metastases in lung was significantly fewer in angiostatin treated mice than in untreated ones, which lived much shorter. No obvious side effects were observed.

CONCLUSION

Angiostatin markedly inhibits the growth and metastasis of LA795 cells on T739 mice and no obvious side effects of angiostatin were found during the treatment.

Epidermal and hepatocyte growth factors stimulate chemotaxis in an intestinal epithelial cell line

The migration of intestinal cells is important in the development and maintenance of normal epithelium, in a process that may be regulated by growth factors and cytokines. Although a number of growth factor receptors are expressed by intestinal cells, little progress has been made toward assignment of functional roles for these ligand-receptor systems. This study compares several growth factors and cytokines for their chemoattraction of the mouse small intestinal epithelial cell line. Epidermal and hepatocyte growth factors stimulated a rapid 30-fold chemotaxis of cells with delayed threefold migration toward transforming growth factor-beta1. Despite stimulating proliferation, keratinocyte, fibroblast, or insulin-like growth factors did not stimulate directed migration. Chemotaxis required tyrosine kinase and phosphatidylinositol phospholipase C activities but not protein kinase C or mitogen-activated protein kinase activity. These findings suggest that the repertoire of growth factors capable of regulating directed intestinal epithelial cell migration is limited and that a divergence exists in the signal transduction pathways for directed vs. nondirected migration.