Effects of Smart City Construction on the Quality of Public Occupational Health: Empirical Evidence From Guangdong Province, China

This article takes the Guangdong Province of China as the research object and uses the difference-in-difference model to evaluate the impact of smart city construction on the quality of public occupational health and intercity differences. The obtained results show that smart city construction significantly improves the quality of public occupational health, and it is still valid after a series of robustness tests. The effect of this policy is stronger in cities that belong to the Pearl River Delta region or sub-provincial level cities. This study indicates that the central government should improve the pilot evaluation system and the performance appraisal mechanism of smart cities from the perspective of top-level design during the process of promoting smart city construction, which aims to correctly guide local governments to promote the construction of smart cities. To achieve the full improvement effect of smart city construction on the quality of public occupational health, local governments should implement smart city strategies in a purposeful and planned way according to the actual situation of the development of the jurisdiction.

Application of polarization information to a light-controlling-light technique

Nonlinear effects of photo-induced waveguides based on isomerization photochemistry are investigated. It is found that polarization information of the controlling light can be used to control the propagation of the signal light in all-optical waveguides, and an accurate and convenient light-controlling-light scheme is proposed, that is, controlling propagation of the signal light by synergic use of the intensity information and polarization information of the controlling light. The polarization dependence of optical nonlinearity is expected to enrich the connotation of the optical nonlinear effects and has theoretical significance and practical value.

[Preparation of chaperone-antigen peptide vaccine derived from human gastric cancer stem cells and its immune function]

Objective: To explore the method of extracting chaperone antigen peptide complexes from gastric cancer stem cells and its immune function. Methods: Gastric cancer stem cells and gastric cancer cells were screened by low temperature ultrasonic lysis. After salting out and dialysis, the lysate supernatant was processed with SDS-PAGE to analyze the expression of chaperone antigen peptide complexes, and then was separated and purified with CNBr-activated SepharoseTM 4B. Reverse high pressure liquid chromatography (HPLC), SDS-PAGE and Western blotting were used to analyze the purity and nature of the acquired albumen. Lymphocyte proliferation assay and lymphocytotoxicity assay were used to ditermine the immunological activity of the chaperone-antigen peptide complexes. Results: The chaperone antigen peptide complexes of gastric cancer stem cells were prepared and identified successfully, of which the main components were the antigen peptides of HSP60, HSP70, HSP90 and HSP110. 0.75 μg and 1.00 μg HSP70-antigen peptide and 1.00 μg HSP90-antigen peptide activated lymphocytes significantly. Their A(490) values were 0.26±0.03, 0.45±0.05 and 0.32±0.04, respectively, while the corresponding doses of HSP60-antigen peptide and HSP110-antigen peptide did not activate lymphocytes. The killing rates of 1.00 μg HSP70-antigen peptide and 1.00 μg HSP70 were (45.0±2.0)% and (16.0±2.0)%, respectively, showing a significant difference (P=0.012). Similarly, the killing rates of 1.00 μg HSP90-antigen peptide and 1.00 μg HSP90 were (36.0±5.0)% and (13.0±4.0)%, respectively, also showing a significant difference (P=0.048). Conclusions: The amount of chaperone antigen peptide complexes in gastric cancer cells is extremely low, but it is obviously increased in gastric cancer stem cells. After purification, the chaperone antigen peptide complexes with high purity can be prepared. The extracted chaperone antigen peptide complexes have stronger immunogenicity, and can be used to make tumor vaccine in vitro, which may have a good application value in the targeted therapy of gastric cancer.

[Changes and the impact on immune function of opioid-dependent subjects by Jitai tabelets during the withdrawal stage]

Objective: To detect the changes in the immune function of opioid-dependent subjects during the withdrawal stage through the administration of Jitai tablet. Methods: Subjects were treated as Jitai tablet alone, Jitai tablet plus buprenorphine and placebo, in a randomized,double-blind, placebo-controlled trial. Before and after the 14(th) day of withdrawal, levels of immunoglobulin (IgM, IgA, IgG), T cell subsets (CD(3)(+), CD(4)(+), CD(8)(+), CD(4)(+)/CD(8)(+)) and cytokines (IL-2, IFN-γ, IL-4, IFN-γ/IL-4) were detected. Results: Compared with healthy people, immunity function before withdrawal among the opioid abusers showed higher levels of IgM, IL-2, IFN-γ, IL-4 and lower level of CD(3)(+)T, as (1.67±0.87) g/L, (14.44±13.50)%, (20.23±15.10)%, (1.97±1.59)%, (47.01±13.62)%, respectively, with difference statistically significant (P<0.05). There was no big difference of other immunity indicators between the two groups (P>0.05). At the 14(th) day of withdrawal in placebo group, levels of IL-4 returned to normal while IFN-γ/IL-4 ratio increased by 3.43 times (P<0.05). Levels of IgA, IgG, CD(4)(+) and CD(4)(+)/CD(8)(+) ratio fluctuated within normal range. There were no significant changes in other immunity indicators (P>0.05). Compared with placebo group, fluctuation of IgG and IgM decreased in Jitai group during withdrawal period, together with a normal level of IgM at the 14(th) day. Level of IL-4 abnormally rose up by 0.54 times in Jitai tablet plus buprenorphine group, while IFN-γ/IL-4 ratio been switched back at the 14(th) day of withdrawal. Other immune indicators were not affected by medical interventions. Conclusion: We noticed that certain impairment of the immune function might be restored by Jitai tablet during the withdrawal period.

Development of calibration facility for radon and its progenies at NIM (China)

Accurate measurement of radon and its progenies is the basis to control the radon dose and reduce the risk of lung cancer caused. The precise calibration of measuring instrument is an important part of the quality control of measurements of the concentration of radon and radon progenies. To establish Chinese national standards and realise reliable calibrations of measuring instrument for radon and its progenies, a radon chamber with regulation capability of environmental parameters, aerosol and radon concentrations was designed and constructed at National Institute of Metrology (NIM). The chamber has a total volume of ∼20 m(3) including an exposure volume of 12.44 m(3). The radon concentration can be controlled from 12 Bq m(-3) to the maximum of 232 kBq m(-3). The regulation range of temperature, relative humidity and aerosol are 0.66 -44.39°C, 16.4 -95 %RH and 10(2) -10(6) cm(-3), respectively. The main advantages of the NIM radon chamber with respect to maintaining a stable concentration and equilibrium factor of radon progenies in a wide range through automatic regulation and control of radon and aerosol are described.

The antidiabetic and hepatoprotective effects of magnolol on diabetic rats induced by high-fat diet and streptozotocin

The effects of magnolol (Mag) on hyperglycemia and hyperlipemia, hepatic oxidative stress and cytochrome P4502E1 (CYP2E1) activity of diabetic rats induced by high-fat diet (HFD) and streptozotocin (STZ) were studied. After oral administration of Mag (25, 50 and 100 mg x kg(-1) x d(-1)) for continuous 10 weeks, the blood glucose and lipids (TC, TG and LDL-C) levels, as well as the hepatic CYP2E1 activity and MDA content of diabetic rats, decreased significantly (P < 0.05 or P < 0.01), whereas the oral glucose tolerance and hepatic antioxidant enzymatic activities (CAT and GSH-Px) of diabetic rats, increased significantly (P < 0.05 or P < 0.01). The results indicated that Mag was effective against the hepatic oxidative damage, hyperglycemia and hyperlipemia of diabetic rats induced by HFD and STZ, and the inhibition of Mag on hepatic CYP2E1 activity could be an important mechanism of Mag against hepatic insulin resistance and oxidative damage.

PGC-1alpha coactivates estrogen-related receptor-alpha to induce the expression of glucokinase

Peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) is a key regulator of cellular energy metabolism and regulates processes such as adaptive thermogenesis, hepatic gluconeogenesis, fatty acid oxidation, and mitochondrial biogenesis by coactivating numerous nuclear receptors and transcription factors. Here, we demonstrate the presence of the ERRalpha binding site in the regulatory sequence of the glucokinase gene and that PGC-1alpha coactivates ERRalpha to stimulate the transcription of glucokinase. Simultaneous overexpression of PGC-1alpha and ERRalpha potently induced the glucokinase gene expression and its enzymatic activity in primary hepatocytes; however, expression of either PGC-1alpha or ERRalpha alone had no significant effect. Electrophoretic mobility shift and chromatin immunoprecipitation assays revealed the interaction of ERRalpha with the glucokinase promoter. Finally, the knockdown of endogenous ERRalpha with specific siRNA (siERRalpha) or pharmacological inhibition of ERRalpha with XCT790 attenuated insulin-induced glucokinase expression. Taken together, this research identifies glucokinase as a novel target of PGC-1alpha/ERRalpha and underscores the regulatory function of ERRalpha in insulin-dependent enzyme regulation.

Detection of chromosomal aberrations by fluorescence in situ hybridization in cervicovaginal biopsies from women exposed to diethylstilbestrol in utero

Epidemiologic studies have associated estrogens with human neoplasms such as those in the endometrium, cervix, vagina, breast, and liver. Perinatal exposure to natural (17beta-estradiol [17beta-E(2)]) and synthetic (diethylstilbestrol [DES]) estrogens induces neoplastic changes in humans and rodents. Previous studies demonstrated that neonatal 17beta-E(2) treatment of mice results in increased nuclear DNA content of cervicovaginal epithelium that precedes histologically evident neoplasia. In order to determine whether this effect was associated with chromosomal changes in humans, the frequencies of trisomy of chromosomes 1, 7, 11, and 17 were evaluated by the fluorescence in situ hybridization (FISH) technique in cervicovaginal tissue from 19 DES-exposed and 19 control women. The trisomic frequencies were significantly elevated in 4 of the 19 (21%) DES-exposed patients. One patient presented with trisomy of chromosomes 1, 7, and 11, while trisomy of chromosome 7 was observed in one patient. There were two patients with trisomy of chromosome 1. Trisomy of chromosomes 1, 7, 11, and 17 was not observed in the cervicovaginal tissue taken from control patients. These data suggest that DES-induced chromosomal trisomy may be an early event in the development of cervicovaginal neoplasia in humans.

A new aspect of view in synthesizing new type beta-adrenoceptor blockers with ancillary antioxidant activities

A series of vanilloid-type beta-adrenoceptor blockers derived from antioxidant traditional Chinese herbal medicines were synthesized and tested for their antioxidant and adrenoceptor antagonistic activities. They all possessed significant beta-adrenoceptor blocking activities under in vitro experiments and radioligand binding assays. In addition, some compounds were further examined in in vivo tests and produced antagonist effects matching that of propranolol and labetalol by measurements of antagonism toward (-)isoproterenol-induced tachycardia and (-)phenylephrine-induced pressor responses in anesthetized rats. Furthermore, all of the compounds had antioxidant effects inherited from their original structures. In conclusion, compound 11 had the most potent beta-adrenoceptors blocking activity, 12 and 13 possessed high cardioselectivity, whereas 14, 15 and 16 possessed additional alpha-adrenoceptor blocking activity and 15 is the most effective antioxidant of all. The antioxidant activity may be due to their alpha and beta unsaturated side chain at position 1 and ortho-substituted methoxy moiety on 4-phenoxyethylamine.

Genetic abnormalities specifically associated with varying metastatic potential of prostate cancer cell lines as detected by comparative genomic hybridization

Established recently are two in vivo prostate tumor progression models in which subclones of the PC3M and LNCaP cell lines were selected for varying growth characteristics and metastatic potential after successive orthotopic implantation in the prostate of nude mice. In this study, we used comparative genomic hybridization (CGH) to compare the chromosomal abnormalities between the parental cell lines and their respective variants and to determine if specific chromosomal abnormalities can be identified that are associated with different growth properties. PC3M and its derivative cell lines PC3M-Pro4 and PC3M-LN4 shared gains of 8q22--qter, 10q21--q22, and Xq27--qter and loss of 13q33--qter. PC3M-Pro4, a derivative line that produced significantly larger tumors in the prostate, had a unique gain of 3q13. In contrast, PC3M-LN4, the derivative line that produced significantly larger metastatic tumors in the lymph nodes and had higher incidences of distant metastases, had a specific gain of 1q21--q22 and losses of 10q23--qter and 18q12--q21. In the second in vivo model, LNCaP and its derivative cell lines shared gain of 3q27--qter and loss on 13q21--qter. The derivative line that produced significantly larger tumors in the prostate, LNCaP-Pro5, had a unique gain on 13q12--q13. In comparison, LNCaP-LN3, a derivative line that had a significantly higher incidence of lymph node metastases and produced significantly larger metastatic tumors in the lymph nodes, had specific losses of 16q23--qter and 21q. Interestingly, some regions of loss (e.g., 10q23-->qter, 16q23-->qter, and 18q12-->q21) detected in the variant cell lines correlated well with abnormalities seen in clinical prostate cancer cases. Thus, our data suggest not only that these cell lines are relevant in vivo models for prostate cancer progression, but also that CGH is a valuable tool for uncovering chromosomal regions that are important for aggressive growth and metastasis of prostate cancer cells.

Time-dependent astroglial changes after gamma knife radiosurgery in the rat forebrain

OBJECTIVE

Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries.

METHODS

Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes).

RESULTS

Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side.

CONCLUSION

During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target.

Effect of dizocilpine maleate on discriminative properties of methamphetamine in rats

AIM

To study the effect of (+)-10, 11-dihydro-5-methyl-5H-dibenzo [a, d] cyclohepten-5, 10-imine maleate(dizocilpine maleate, MK-801) on the discriminative behavior of methamphetamine (MA).

METHODS

Two lever and a fixed-ratio schedule of food presentation reinforcement program were used in discrimination test session.

RESULTS

Rats can shape and maintain the discriminative behavior for MA (1 mg/kg, s.c.) and saline (1 mL/kg, s.c.). On pretreatment with dizocilpine maleate (0.1 mg/kg) in MA dependent rats, the correct discrimination percentage of MA was markedly decreased; but pretreatment with dizocilpine maleate (0.025, 0.05 mg/kg) did not block discrimination behavior of MA in antagonistic test. After injection of dizocilpine maleate (0.1 mg/kg) alone in MA dependent rats, six of the seven rats partially or completely responded on the MA associated lever whereas one did not. All of the rats had no substitution after injection of dizocilpine maleate (0.025, 0.05 mg/kg).

CONCLUSION

N-methyl-D-aspartate (NMDA) receptor may be involved in psychological dependence of MA.

Statistical models for analysis of cytogenetic biomarkers

BACKGROUND

Bleomycin-induced chromosomal breaks (CB) and sister chromatid exchange (SCE) in peripheral blood lymphocytes have been shown to be sensitive cytological markers for susceptibility to DNA damage in patients with various types of cancer and in healthy controls. Factors such as age, sex, smoking, and alcohol consumption could affect the values of some of these biomarkers and should be considered as covariates when analyzing cytogenetic biomarkers because these factors can affect the frequency of CB and SCE.

METHODS

We propose a statistical method using negative binomial (NB) distribution to evaluate the numbers of CB and SCE. In order to determine the best model to represent the frequency of CB and SCE, we compared the NB model with the widely used Poisson model and log-transformed normal model by using generalized linear models. To demonstrate the better fit of the NB model, we analyzed three different data sets from studies conducted at The University of Texas M.D. Anderson Cancer Center. The first set was a case-control study of lung cancer in a population of African Americans and Mexican Americans (286 cases and 156 controls), the second set consisted of 311 head and neck cancer patients, and the third set consisted of 105 Hodgkin's disease patients.

RESULTS

For CB; the estimates of the variability for Hodgkin's disease, head and neck, and lung cancers were 487.24, 502.82, and 520.15, respectively. For SCE, the estimates of the variability for Hodgkin's disease was 9777.01. For CB, the dispersion estimates under the three models (Poisson, NB, and Normal) for Hodgkin's disease, head and neck, and lung cancers were: 12.30, 1.20, 0.85; 8.94, 1.05, 0.22; and 10.10, 1.05, 0.25, respectively. For SCE (Hodgkin's disease only), the dispersion estimates under the three models (Poisson, NB, and Normal) were 30.91, 1.11, 0.10, respectively.

CONCLUSIONS

Our results demonstrate that the NB model provides a better interpretation and fit for the frequency of CB and SCE in different cancer types. Therefore, we recommend it as a model for the analysis of cytogenetic biomarkers.

Pharmacological effects of an aldehyde type alpha/beta-adrenoceptor blocking agent with vasodilating properties

KMUP 880723 (0.5, 1.0, and 3.0 mg/kg, iv) produced dose-dependent hypotensive and bradycardia responses in pentobarbital-anesthetized Wistar rats. KMUP 880723 (1.0 mg/kg, iv) also markedly inhibited both the tachycardia effects induced by (-)isoproterenol and arterial pressor responses induced by phenylephrine. In the isolated Wistar rat right atria, left atria, and guinea pig tracheal strips, KMUP 880723 competitively antagonized the (-)isoproterenol-induced positive chronotropic effects, inotropic effects, and tracheal relaxation effects in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol suggested that KMUP 880723 was a beta(1)/beta(2)-adrenoceptor competitive antagonist. The apparent pA(2) values were 6.89+/-0.10 in the right atria, 7.02+/-0.09 in the left atria, and 6.59+/-0.11 in the trachea, indicating that KMUP 880723 was a nonselective beta-adrenoceptor blocker. In thoracic aorta experiments, KMUP 880723 also produced a competitive antagonism of norepinephrine-induced contraction with a pA(2) value of 7.14+/-0.06. In isolated rat thoracic aorta, KMUP 880723 more potently relaxed the contractions induced by norepinephrine (3 x 10(-6) M) than those by high K(+) (75 mM). In the radioligand-binding assay, the pK(i) values of [3H]CGP-12177 binding to rat ventricle and lung membranes were 6.56 and 6.40, respectively, and the value of [3H]prazosin binding to rat brain membranes was 6.66. These results further confirmed the alpha/beta-adrenoceptor blocking activities of KMUP 880723 reported in the functional studies. We conclude that KMUP 880723 is a nonselective beta-adrenoceptor antagonist with alpha-adrenoceptor blocking-associated vasorelaxant activity.

Deletions of chromosome 5q13.3 and 17p loci cooperate in myeloid neoplasms

Nonrandom interstitial deletions and monosomy of chromosomes 5, 7, and 17 in refractory myelodysplasia (MDS) and acute myelogenous leukemia (AML) suggest a multistep pathway that culminates in aggressive clinical course. Because cytogenetic studies frequently identify chromosome 5 and 17 deletions within a single clone, we searched for allele loss for 5q loci and TP53 gene mutations in the same leukemic samples. Cosegregating deletions of chromosomes 5 and 17 were found to specifically include the 5q13.3 interval between the loci D5S672 and D5S620/D5S626, a locus hypothesized to harbor a tumor suppressor gene(1) and the TP53 gene on 17p. A rare patient with secondary refractory MDS and an unbalanced translocation [der(5;17)], which resulted in deletions of the 5q13.3-qter and 17p loci, provided clues on the sequence of genetic alterations. Serial molecular analysis of this patient revealed a dysplastic clone with der(5;17), which gave rise to a leukemic clone on acquiring an inactivating mutation of TP53. Our findings are consistent with functional cooperation between a putative tumor suppressor gene at 5q13.3 that contributes toward the progression of early stages of MDS, and the TP53 gene when mutated, causes transformation to AML. (Blood. 2000;95:2138-2143)

Coherent acoustic phonon oscillations in semiconductor multiple quantum wells with piezoelectric fields

Large coherent acoustic phonon oscillations were demonstrated using InGaN/GaN multiple quantum wells with piezoelectric fields. With UV femtosecond pulse excitation, photogenerated carriers screened the piezoelectric field and initiated the displacive coherent phonon oscillations. The specific phonon frequency was selected by the coupling between the periodic carrier distribution and the corresponding acoustic phonon mode. The induced acoustic phonon oscillation resulted in piezoelectric field modulation and then caused absorption variation through the quantum confined Franz-Keldysh effect. The wave vector uncertainty due to the finite sample width was found to determine the observed dephasing time.

Vanidipinedilol: a vanilloid-based beta-adrenoceptor blocker displaying calcium entry blocking and vasorelaxant activities

Calcium channel and beta-adrenoceptor blockade have proved highly useful in antihypertensive therapy. Studies of the mechanisms of action of vanidipinedilol that combine these effects within a single molecule are described here. Intravenous injection of vanidipinedilol (0.1, 0.25, 0.5, 1.0, and 2.0 mg/kg) produced dose-dependent hypotensive and bradycardic responses, significantly different from nifedipine-induced (0.5 mg/kg, i.v.) hypotensive and reflex tachycardic effects in pentobarbital-anesthetized Wistar rats. A single oral administration of vanidipinedilol at doses of 10, 25, and 50 mg/kg dose-dependently reduced blood pressure with a decrease in heart rate in conscious spontaneously hypertensive rats (SHRs). In the isolated Wistar rat atrium, vanidipinedilol (10(-7), 10(-6), and 10(-5) M) competitively antagonized the (-)isoproterenol-induced positive chronotropic and inotropic effects and inhibited the increase in heart rate induced by Ca2+ (3.0-9.0 mM) in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol and CaCl2 suggested that vanidipinedilol possessed beta-adrenoceptor-blocking and calcium entry-blocking activities. On tracheal strips of reserpinized guinea pig, cumulative doses of vanidipinedilol (10(-10) to 3x10(-6) M) produced dose-dependent relaxant responses. Preincubating the preparation with ICI 118,551 (10(-10), 10(-9), 10(-8) M), a beta2-adrenoceptor antagonist, shifted the vanidipinedilol concentration-relaxation curve significantly to a region of higher concentrations. These results implied that vanidipinedilol had a partial beta2-agonist activity. In the isolated thoracic aorta of rat, vanidipinedilol had a potent effect inhibiting high-K+-induced contractions. KCI-induced intracellular calcium changes of blood vessel smooth muscle cell (A7r5 cell lines) determined by laser cytometry also was decreased after administration of vanidipinedilol (10(-8), 10(-7), 10(-6) M). Furthermore, the binding characteristics of vanidipinedilol and various antagonists were evaluated in [3H]CGP-12177 binding to ventricle and lung and [3H]nitrendipine binding to cerebral cortex membranes in rats. The order of potency of beta1- and beta2-adrenoceptor antagonist activity against [3H]CGP-12177 binding was (-)propranolol (pKi, 8.59 for beta1 and 8.09 for beta2) > vanidipinedilol (pKi, 7.09 for beta1 and 6.64 for beta2) > atenolol (pKi, 6.58 for beta1 and 5.12 for beta2). The order of potency of calcium channel antagonist activity against [3H]nitrendipine binding was nifedipine (pKi, 9.36) > vanidipinedilol (pKi, 8.07). The ratio of beta1-adrenergic-blocking/calcium entry-blocking selectivity is 0.1 and indicated that vanidipinedilol revealed more in calcium entry-blocking than in beta-adrenergic-blocking activities. It has been suggested that vanidipinedilol-induced smooth muscle relaxation may involve decreased entry of Ca2+ and partial beta2-agonist activities. In conclusion, vanidipinedilol is a nonselective beta-adrenoceptor antagonist with calcium channel blocking and partial beta2-agonist associated vasorelaxant and tracheal relaxant activities. Particularly, the vasodilator effects of vanidipinedilol are attributed to a synergism of its calcium entry blocking and partial beta2-agonist activities in the blood vessel. A sustained bradycardic effect results from beta-adrenoceptor blocking and calcium entry blocking, which blunts the sympathetic activation-associated reflex tachycardia in the heart.

Enzyme-histochemical demonstration of lymphatic vessels in the golden hamster periodontium: an attempt to reactivate the 5'-nucleotidase activity with Mg++ ion supply

Enzyme-histochemical demonstration of lymphatic vessels in the golden hamster periodontium was performed on cryostat sections using the 5'-nucleotidase (5'-Nase) staining method by light microscopy and backscattered electron imaging of scanning electron microscopy. The inhibition of the 5'-Nase activity by decalcification was cancelled by the Mg++ ion supply. The reaction products of 5'-Nase activity were produced on the lymphatic endothelial cells and the tubular structures of lymphatic vessels were seen as highlights by backscattered electron imaging. The invasion of 5'-Nase-positive lymphatic vessels into the alveolar bone from the periodontium was found in the present study.

Spectral karyotypic study of the HL-60 cell line: detection of complex rearrangements involving chromosomes 5, 7, and 16 and delineation of critical region of deletion on 5q31.1

Interstitial deletions of the q arm of chromosome 5 have been associated with acute myelogenous leukemia (AML); therefore, accurate identification of rearrangements of this chromosome in a model cell line, HL-60, is important for understanding the critical genes involved in this disease. In this study, we employed a newly developed technology termed spectral karyotyping to delineate chromosomal rearrangements in this cell line. Our study revealed a derivative of chromosome 7 that resulted from translocations of chromosome arms 5q and 16q to 7q; that is, der(7)t(5;7)(?;q?)t(5;16)(?;q?). Interestingly, both chromosomes 5 and 7 were also involved in translocations with chromosome 16 in der(16) t(5;16)(q?;q?22-24) and der(16)t(7;16)(?;q?22-24), respectively. Other notable chromosomal abnormalities that were not previously reported in the HL-60 included an insertion of chromosome 8 in the q arm of chromosome 11, a translocation between chromosomes 9 and 14, and a translocation between chromosomes 14 and 15. In an attempt to define the loss of the 5q31.1 region in HL-60, we performed fluorescence in situ hybridization analysis by utilizing bacterial artificial chromosomes BAC1 and BAC2 that spanned the IL9 and EGR1 gene interval, which was previously shown to be a critical region of loss in AML. We showed that a copy of both BAC1 (spanning the D5S399 locus) and BAC2 (spanning the D5S393 locus centromeric to BAC1) were present in the normal chromosome 5, but a second copy of BAC1 was lost and a second copy of BAC2 was inserted in the der(16)t(7;16) chromosome. Thus, not only was this study the first to use the new 24-color karyotyping technique to identify several novel chromosomal rearrangements in HL-60, but it also narrowed the 5q31.1 critical region of deletion to the region represented by BAC1.

Dendritic cells derived in vitro from acute myelogenous leukemia cells stimulate autologous, antileukemic T-cell responses

We have previously reported that leukemic dendritic cells (DC) can be generated ex vivo from myelomonocytic precursors in chronic myelogenous leukemia. In this study we report the generation of DC from acute myelogenous leukemia (AML) cells and their potent ability to stimulate leukemia-specific cytolytic activity in autologous lymphocytes. DC were generated in vitro using granulocyte-macrophage colony-stimulating factor +interleukin-4 in combination with either tumor necrosis factor-alpha or CD40 ligand (CD40L). Cells from 19 AML patients with a variety of chromosomal abnormalities were studied for their ability to generate DC. In all but 1 case, cells with the morphology, phenotypic characteristics, and T-cell stimulatory properties of DC could be generated. These cells expressed high levels of major histocompatibility complex class I and class II antigens as well as the costimulatory molecules B7-2 and ICAM-1. In three cases these cells were determined to be of leukemic origin by fluorescence in situ hybridization for chromosomal abnormalities or Western blotting for the inv(16) fusion gene product. Autologous lymphocytes cocultured with AML-derived DC (DC-AL) were able to lyse autologous leukemia targets, whereas little cytotoxicity was noted against autologous, normal cells obtained from the patients during remission. We conclude that leukemia derived DC may be useful for immunotherapy of many AML patients.

Expression and significance of three types of Fos-immunoreactive cells after gamma knife irradiation of the forebrain in the rat

The expression and significance of three types of Fos-like immunoreactive (Li) cells were investigated after gamma knife irradiation of the forebrain in the rat. Three months after the irradiation, the brain sections were immunostained with an antiserum against Fos protein. It was shown that the Fos-like immunoreactivity (LI) appeared in some of the neurons, glial cells and endothelial cells in the target area, the white matter surrounding the lateral ventricle, the cerebral cortex and the hippocampus. Three characteristic types of Fos-Li cells were identified in these regions. (1). Only the nuclei of the cells were Fos-ir, (2). Only the cytoplasm was immunostained, and (3). Both the nuclei and the cytoplasm showed Fos-LI. It is suggested that type 1 are the normal responsive cells, type 2 are seriously injured cells, so that the Fos translocation mechanism is damaged, and type 3 represents the intermediate form.

Exaggerated precocious centromere separation in cells of a human breast cancer line treated with a green tea extract

In a breast cancer cell line, MDA-MB-468, established in our laboratory, an average of 3% of the mitotic cells exhibited a phenomenon known as centromere splaying, which is a characteristic feature of cells of patients with Roberts syndrome. However, centromere splaying in cells of Roberts syndrome patients is limited to i) the centromere region and ii) chromosomes with large amounts of heterochromatin. When the breast cancer cells were treated with an extract of green tea GTE-TP91, up to 45% of the metaphases were observed to exhibit this behavior; and the precocious centromere separation was highly exaggerated, affecting all chromosomes in such metaphases. Apparently, as the sister centromeres continued to pull apart, they carried the chromatids with them, except for the telomere regions, giving a ring-like configuration. Eventually, the sister chromatids became completely separated. Whether this bizarre phenomenon was induced by the polyphenols contained in this green tea extract GTE-TP91 is not known, but this phenomenon, upon further investigation, may throw some light on chromosomal proteins, centromere behavior, telomere behavior and related questions.

Chromosome breaks and sister chromatid exchange as predictors of second cancers in Hodgkin's disease

Hodgkin's disease (HD) survivors face an increased risk of developing second cancers. We evaluated baseline cytogenetic biomarkers, sister chromatid exchange (SCE) and chromosome breaks [spontaneous (SCB) and bleomycin-induced (BIB)], as predictors of second cancer risk in a cohort of 105 adult HD patients. During follow-up, seven second cancers occurred. SCBs and BIBs showed no association with risk of second primaries. Multivariate Cox regression revealed that high levels of SCEs (relative risk (RR)=11.3, p=0.02) and age (RR=1.08, p=0.02) predicted second cancer risk. Histology, stage, and treatment were not associated with elevated risk. In conclusion, baseline SCE frequencies may be a useful biomarker for identifying HD patients at increased risk of developing second cancers. These results need to be verified in a larger cohort with a longer follow-up time.

Evaluation of sister chromatid exchange and chromosome breaks in a cohort of untreated Hodgkin's disease patients

Cytogenetic biomarkers, chromosomal breaks [spontaneous breaks (SB) and bleomycin-induced breaks (BIB)], and sister chromatid exchange (SCE) have been shown to be sensitive cytological assays to defect susceptibility to DNA-damaging effects. However, little information is available on how environmental factors and demographic and clinical characteristics influence variation among individuals. We sought to characterize interindividual variability in a cohort of 105 untreated adult Hodgkin's disease patients. SB, BIB, and SCE data were integrated with epidemiological data by using linear regression analysis. Age, sex, ethnicity, education, histology, history of mononucleosis, and family history of cancer showed no association with any biomarker. In univariate analysis, alcohol intake was significantly associated with high SCEs (P = 0.005) and SBs (P = 0.02). Current smoking was associated only with high frequencies of SCE (P = 0.05). Advanced stage of disease was related with high SBs (P = 0.01). BIBs were not associated with any of the variables studied. In multivariate modeling, current alcohol intake was associated with high SCEs (P = 0.04) and SBs (P = 0.01). Former smokers had higher SBs than nonsmokers did (P = 0.02). A small positive correlation was found among each pair of markers. The higher SCEs and SBs in patients who smoke and consume alcohol indicate the need for evaluating these exposures when interpreting these biomarkers.

Use of leukemic dendritic cells for the generation of antileukemic cellular cytotoxicity against Philadelphia chromosome-positive chronic myelogenous leukemia

The success of adoptive immunotherapy for the treatment of leukemia depends on the generation of T cells that can specifically react with malignant cells. Dendritic cells (DCs) are important antigen-presenting cells in the development of antileukemic T-cell responses. In this study, we generated DCs from peripheral blood cells of patients with chronic myelogenous leukemia (CML). CML cells incubated concurrently with granulocyte-macrophage colony-stimulating factor, interleukin-4, and tumor necrosis factor-alpha in vitro developed morphologic and phenotypic characteristics of DCs. Fluorescence in situ hybridization showed the presence of t(9;22) in the nuclei of these cells, indicating that they were leukemic in origin. These cells were potent stimulators of lymphocyte proliferation in specific in vitro assays for DC function. Autologous T cells stimulated with in vitro-generated, leukemic DCs displayed vigorous cytotoxic activity against CML cells but low reactivity to major histocompatability complex-matched normal bone marrow cells. Cytotoxic activity against CML targets was fourfold to sixfold higher using DC-stimulated autologous T cells than with autologous T cells expanded by culture with interleukin-2 alone. DC-stimulated T cells also inhibited growth of CML clonogenic precursors in colony-forming assays in vitro. These results suggest that cytokine-driven in vitro differentiation of CML cells results in generation of DCs with potent T-cell stimulatory function. In vitro-generated DCs can be effectively used as antigen-presenting cells for the ex vivo expansion of antileukemic T cells.

Translocations and deletions of 5q13.1 in myelodysplasia and acute myelogenous leukemia: evidence for a novel critical locus

Acquired partial and complete deletions of chromosome 5 (5q-, -5) are common cytogenetic anomalies associated with myelodysplasia (MDS) and acute myeloid leukemia (AML). A critical region of consistent loss at 5q31.1 (in > 90% of cases) has led us and others to postulate the presence of a key negative regulator(s) of leukemogenesis. Although the interstitial deletion limits vary among patients, del(5) (q13q33) and del(5)(q13q35) constitute major subsets. Furthermore, it is not rare to encounter deletions, translocations, or paracentric inversions involving 5q11 to 5q13, which indicates inactivation or disruption of important gene(s) at that locus. In this report, we have localized a novel locus at 5q13.1 to a 2.0-Mb interval between the anonymous markers D5S672 and GATA-P1804. This locus resided within the region of loss in 12 of 27 patients with anomalies of chromosome 5; one of these cases had apparent retention of both alleles of all the telomeric loci. Fluorescence in situ hybridization (FISH) studies demonstrate that the AML cell line ML3 is disrupted at 5q13.1 by a translocation involving chromosome 3, with apparent retention of the entire chromosome 5 sequence. Our results suggest that this novel proximal locus encodes a critical gene that may be deleted or disrupted in a subset of MDS/AML patients with chromosome 5 anomalies.

Trisomy 7 by dual-color fluorescence in situ hybridization: a potential biological marker for prostate cancer progression

Smear preparations from fine-needle aspirates of 30 prostatic carcinomas obtained from radical prostatectomy specimens were examined by a dual-color fluorescence in situ hybridization (FISH) method for the presence of chromosome 7 trisomy (chromosome 9 was used as a control). The frequency of cells with trisomy 7 was determined in tumor cells and normal prostatic epithelial cells in each specimen. Comparison between the tumor and normal cells from the same patients showed that within all stages, the frequency of trisomy 7/disomy 9 cells in the tumor cells was significantly higher than that observed in the normal cells (P < 0.0001). Furthermore, the mean frequency of cells with trisomy 7/disomy 9 in advanced stages was significantly elevated over the mean frequency observed in organ-confined tumors (P = 0.02). These results are consistent with our previous data on paraffin-embedded prostate tissue sections using single-color FISH procedures. However, the method used in the present study enhances the accuracy of distinguishing trisomic 7 cells from potentially triploid (trisomy 7/trisomy 9) cells. Furthermore, the use of fine-needle aspirates rather than paraffin sections provides an easy method to examine whole nuclei. Our study also suggests that FISH provides a better measure of genetic instability (e.g., aneuploidy) in prostate tumors than flow cytometry.

Detection of residual leukemic cells in patients with acute promyelocytic leukemia by the fluorescence in situ hybridization method: potential for predicting relapse

The translocation between chromosomes 15 and 17, t(15;17)(q22-24;q11-21), is present in the bone marrow cells of most patients with acute promyelocytic leukemia (APL). Although conventional cytogenetic methods are useful for diagnosing this disease, difficulties are experienced in detecting residual disease among those patients who have achieved remission. In this study, we used the fluorescence in situ hybridization (FISH) method to attempt to detect residual leukemic cells in 10 APL patients in clinical remission. The duration of remission ranged from 2 to 93 months at the time of study. Multiple bone marrow samples were analyzed by FISH in most patients. In 6 patients, no cell with t(15;17) was found. These patients remain in complete remission at present (approximately 25 to 33 months since first studied by FISH). In 4 patients, low frequencies of cells with t(15;17) were observed in at least one bone marrow sample examined. All of these patients relapsed within 1 to 14 months. No cell with t(15;17) was identified by the conventional G-banding method in any sample. The FISH results correlated well with that of a two-round nested reverse transcription polymerase chain reaction assay that was performed on the same samples. Thus, our study suggests that FISH is potentially a useful tool for detecting residual APL cells and for identifying patients at high risk of relapse.

5q- chromosome. Evidence for complex interstitial breaks in a case of refractory anemia with excess blasts

Interstitial loss of the long arm of chromosome 5 (5q-) is an anomaly frequently seen in myelodysplasia (MDS) and acute myelogenous leukemia (AML). Although the limits of the interstitial deletions vary among patients, there is a critical region of overlap at 5q31 that is consistently deleted in most cases. The order of genes in the critical 5q31 region is centromere, interleukin gene cluster, an anonymous polymorphic locus D5S89, early growth response factor, CSF1 receptor, telomere. Fluorescence in situ hybridization of specific 5q31 probes to metaphases with del(5) (q11q31) from a patient with secondary refractory anemia with excess blasts in transformation demonstrates that the interstitial deletion is not contiguous. The 5q- chromosome has lost the D5S89 and CSF1R loci while retaining some of the sequences in between. A probe derived from a 300-kbp yeast artificial chromosome containing the D5S89 locus is interrupted on the normal chromosome 5 of this patient. Data presented in this report are consistent with (i) presence of a critical gene within the YAC and (ii) more than a single interstitial break within the 5q- chromosome. These results, while pinpointing one of the critical 5q31 loci, also provide evidence for a second telomeric locus.

Chromosomal damage in sperm of patients surviving Hodgkin's disease following MOPP (nitrogen mustard, vincristine, procarbazine, and prednisone) therapy with and without radiotherapy

Following fusion with hamster eggs, human sperm chromosomes from six Hodgkin's disease patients were analyzed to determine the genotoxic effects of therapy. Each patient had received two to six cycles of MOPP (nitrogen mustard, vincristine, procarbazine, and prednisone), with or without radiotherapy, from 3 to 20 years before the study. A total of 571 cells from the six patients were analyzed; 9.8% of the cells had structural aberrations, and 1.6% were hyperhaploid. Analysis of 5998 metaphases from a control group of 24 male donors revealed only 6.9% of cells with structural aberrations and 0.8% aneuploidy. The increase in hyperhaploidy in the patients was statistically significant. Thus, results of this study suggest that the MOPP regimen, with or without radiotherapy, is capable of causing chromosome abnormalities in the sperm of Hodgkin's disease patients.

Trisomy 7: a potential cytogenetic marker of human prostate cancer progression

We used the fluorescence in situ hybridization (FISH) method to show that chromosome 7 trisomy is associated with the progression of human prostate cancer. Thirty-six specimens including 15 primary prostate carcinomas, 16 metastatic lesions, and 5 normal prostate tissues, as well as 2 prostate carcinoma cell lines of different tumorigenic potential, were examined for chromosome 7 aneuploidy. Our results showed that the androgen-unresponsive tumorigenic cell line PC-3 exhibited a significantly higher ratio of chromosome 7 to total chromosome number than the androgen-responsive nontumorigenic cell line LNCaP (P = 0.001). In prostate specimens, the frequency of trisomy 7 cells was significantly increased (P < 0.05) in the advanced stage tumors (C and DI) but not in the early (B) stage tumors or normal prostatic tissue. Furthermore, metastases showed a higher frequency of trisomy 7 cells than primary tumors (P = 0.005). In 2 patients with paired primary and metastatic tumors, trisomy 7 cells increased from 4-7% in the primary tumors to 42-45% in the metastatic tumor cells in the bone marrow. Therefore, our data suggest that trisomy 7 may be a common feature associated with local and metastatic progression and serve as a novel marker for human prostate cancer progression.

Comparison between interphase and metaphase cytogenetics in detecting chromosome 7 defects in hematological neoplasias

Monosomy 7 (-7) is one of the most common chromosomal abnormalities found in the leukemic cells of patients with acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS). Because patients with -7 have a poor prognosis, their identification is important for treatment planning. Conventionally, -7 is detected by the G-banding technique. This study examines the use of fluorescent in situ hybridization (FISH) methodology to detect -7 cells in interphase nuclei and metaphase chromosomes. Fifteen AML or MDS patients whose leukemic cells were found to have -7 by G-banding at disease presentation were studied. In 13 of these patients, -7 could be detected in interphase by FISH using a chromosome 7-specific centromeric DNA probe. The two patients whose leukemic cells were not detectable by interphase FISH had -7 and t(1q;7p), which were detectable by FISH in metaphase using a chromosome 7-specific painting probe. Metaphase FISH was particularly useful in further defining chromosome 7 defects in cells that contained aberrant or marker chromosomes. For example, in 6 patients, chromosome 7 sequences were detectable in aberrant or marker chromosomes by metaphase FISH, but not by G-banding. These results suggest that metaphase FISH is an important adjunct to conventional cytogenetic methods for defining chromosome 7 abnormalities in AML and MDS patients. Furthermore, interphase FISH is useful for follow-up studies in patients who are found informative for the FISH study at presentation.

A new chemotherapy regimen for treatment of Hodgkin's disease associated with minimal genotoxicity

Recently, the combination chemotherapy Novantrone, Oncovin, Velban, Prednisone [NOVP] was developed by The University of Texas M. D. Anderson Cancer Center for treatment of Hodgkin's disease [HD]. Preliminary clinical results show that NOVP is as effective as the traditional Mechlorethamine, Oncovin, Procarbazine, Prednisone [MOPP] regimen in achieving remission, but with fewer side-effects. To determine if NOVP is genotoxic, we studied the induction of chromosome breaks and sister chromatid exchanges [SCEs] in lymphocytes of 42 HD patients both before and during NOVP treatment. Furthermore, in vitro bleomycin treatment was used to unmask potential single-stranded DNA breaks inducted by the therapy. Our results showed that NOVP did not cause elevated levels of chromosome or single-stranded DNA breaks, or SCEs. These results together with previous findings that NOVP caused minimal acute and gonadal toxicities suggest that NOVP is less toxic than MOPP. Therefore, this new regimen shows promise as an effective and minimally toxic regimen for treatment of HD.

Advances in the diagnosis of acute leukemia

The diagnosis and monitoring of acute leukemia requires a multiparameter approach. Although the foundation of diagnosis continues to depend on morphologic and cytochemical determinations, the importance of immunologic, cytogenetic, and molecular classifications is beginning to be emphasized and addressed worldwide. In addition to aiding in the diagnosis of acute leukemia, the information gained by these studies increases the understanding of the pathobiology of these neoplasms.

Detection of residual proliferating leukemic cells by fluorescence in situ hybridization in CML patients in complete remission after interferon treatment

Interferon-alpha produces a complete hematologic and cytogenetic remission in approximately 20% of patients with chronic myelogenous leukemia (CML). In this study, we applied fluorescent in situ hybridization (FISH) methodology to examine the possibility that a low level of proliferating Philadelphia-chromosome-positive (Ph+) cells may be present in interferon-treated CML patients who have achieved complete cytogenetic remission (as defined by the absence of Ph chromosome in 20-25 metaphases analyzed). Ten such patients in remission for 6-35 months were studied by this technique, in which a chromosome-22-specific DNA painting probe was used to detect leukemic cells with the characteristic 9;22 chromosomal translocation. In six of the 10 patients (60%), 3-9% Ph+ metaphases were detected. No Ph+ cells were observed in nine control individuals. Thus, this study demonstrates that FISH technology is more sensitive than conventional cytogenetic analysis for the detection of minimal residual disease in CML.

Trisomy 8p: unusual origin detected by fluorescence in situ hybridization

Chromosomal analysis of a neonate with brain and heart abnormalities revealed trisomy for 8p. The mother's karyotype showed 47 chromosomes with one chromosome 8 being represented as two separate chromosomes, an acrocentric 8p and a telocentric 8q. G-banding and silver staining revealed a satellite and nucleolus organizing region (NOR) on the 8p. Centromeric-specific probes to the centromeres of chromosomes 8, 15, 13/21, 22 and the acrocentric chromosomes revealed that only the 8q centromere was of chromosome-8 origin, while the 8p centromere was of chromosome-14 origin.

Development of a cell surface reacting human monoclonal antibody recognizing ovarian and certain other malignancies

A human monoclonal antibody designated AC6C3 was developed by fusing regional lymph node lymphocytes from a patient with epithelial ovarian carcinoma with cells of the hybrid myeloma SPAZ 4. This monoclonal antibody recognized a determinant expressed on the cell surface of ovarian tumor cell lines. The AC6C3 hybridoma has been maintained for more than 24 months by repeated cloning and secretes IgM at concentrations of 2-8 micrograms/10(6) cells/24h. The AC6C3 monoclonal antibody reacted with a cell surface component of ovarian tumor cell lines, as determined by cell surface immunofluorescence staining using the fluorescent activated cell sorter (FACS). In contrast, nylon wool nonadherent peripheral blood lymphocytes or red blood cells from normal donors were negative (less than 5% of the cells were stained). Immunoperoxidase staining with the AC6C3 monoclonal antibody of nonpermeabilized cryostat sections of freshly obtained or cryopreserved ovarian carcinoma specimens and human ovarian tumor xenografts demonstrated strong reactivity of these specimens. Most normal tissues including brain, liver, heart, kidney and peritoneum demonstrated negative or weak reactions with AC6C3. Other carcinomas including breast, colon and some malignancies of neuroectodermal origin were strongly reactive with AC6C3. AC6C3 mediated complement-dependent cytotoxicity and identified a 32 Kd band in Western blotting and immunoprecipitation experiments conducted on surface labelled SKOV3 cells. The association constant for AC6C3 was determined at 2.3 x 10(10) M-1.

NOVP: a novel chemotherapeutic regimen with minimal toxicity for treatment of Hodgkin's disease

Patients with early-staged Hodgkin's disease have had a higher relapse rate following radiotherapy alone if they have B symptoms, large mediastinal masses, hilar involvement, or stage III disease. From June 1988 to December 1989, 27 previously untreated patients with early-staged Hodgkin's disease with adverse features for disease-free survival received combined-modality therapy. Seventeen patients had stage I or II disease, 10 had stage III, 5 had B symptoms, 13 had large mediastinal masses, and 6 had peripheral masses measuring 10 cm or more in diameter. All patients initially received three cycles of a novel chemotherapeutic regimen combining Novantrone (mitoxantrone, American Cyanamid Company), vincristine, vinblastine, and prednisone (NOVP). Twenty-four patients with clinically staged I or II disease with adverse features or stage III disease did not undergo laparotomy; three patients had favorable stage I or II disease and at laparotomy had stage III disease. Radiotherapy-treatment fields depended on the extent of nodal involvement. Twenty-six patients completed all therapy as planned to complete remission (CR) and one of these has had progression; she is in second CR following additional radiotherapy. With a median follow-up of 12 months, all patients are alive. Tolerance to treatment was excellent with only grade 1 or 2 nausea, alopecia and myalgias, and brief myelosuppression. NOVP is an effective adjuvant chemotherapy regimen for inducing responses, with minimal toxicity, prior to definitive radiotherapy for patients with early-staged Hodgkin's disease.

Chromosomal breakpoints within the first intron of the ABL gene are nonrandom in patients with chronic myelogenous leukemia

Bone marrow cells from 37 patients with chronic myelogenous leukemia (CML), who had the characteristic Philadelphia chromosome in their leukemic cells, were examined for ABL gene rearrangement by pulsed-field gel electrophoresis. By using several probes from the ABL gene, we found that in 33 of 37 (89%) patients studied, the translocation breakpoints in ABL fell within the 175-kilobase (kb) intron between exons 1b and 1a. Furthermore, breakpoints in this intron clustered in three regions, approximately 30 +/- 5, 100 +/- 13, and 135 +/- 8 kb downstream from exon 1b. These findings suggest that there may be specific sequences in this intron that facilitate the processes of chromosomal translocation.

Induction of chromosome breaks and sister chromatid exchanges in patients with Hodgkin's disease by two combination chemotherapy regimens of different leukemogenic potential

The success of various combination chemotherapies in the treatment of cancer is compromised by their potential to cause secondary leukemia. Previous studies have suggested that the alkylating agents used in some regimens are the major etiological factor in these leukemias. In this study, we compared the abilities of two standard regimens used in the treatment of Hodgkin's disease to cause chromosome breaks and sister chromatid exchanges, the two most common types of chromosomal damage induced by alkylating agents. These regimens are MOPP [mechlorethamine-vincristine (Oncovin)-procarbazine-prednisone] and CVPP-ABDIC [cyclophosphamide-vinblastine-procarbazine-prednisone-doxorubicin (Adriamycin)-bleomycin-dacarbazine-1-(2-chloroethyl)-3-cyclohexyl-1- nitrosourea]. Our study demonstrated that (a) levels of spontaneous chromosome breaks and sister chromatid exchanges were low in untreated Hodgkin's disease patients; (b) significantly higher levels of these damages were induced in patients receiving eight cycles of CVPP-ABDIC, as compared with their pretreatment levels; (c) significantly elevated levels of sister chromatid exchanges, but not chromosome breaks, were induced in patients receiving two cycles of MOPP; and (d) no differences in the effect of these two regimens on cell cycle kinetics were observed. Although MOPP therapy has been reported to have higher rates of secondary leukemia than CVPP-ABDIC, our studies show that eight cycles of CVPP-ABDIC are more potent than two cycles of MOPP in inducing chromosome damage in patients during treatments.

Low levels of chromosomal mutations in germ cells derived from doxorubicin-treated stem spermatogonia in the mouse

The mutagenic effects of doxorubicin (Adriamycin, ADR) on mouse spermatogonial stem cells were examined by analysis of spermatocyte chromosomes and of dominant lethality transmitted through the spermatozoa. The effects of ADR on mutations, cytotoxicity, and sperm head abnormalities were compared with those of radiation. The cytotoxic effect of 6 Gy of gamma-radiation on stem spermatogonia was equivalent to about 4-5 mg ADR/kg. Chromosomal translocations were observed in 0.6% of the spermatocytes of mice treated with ADR (2-6 mg/kg). In contrast, 6 Gy of radiation induced translocations in 11.1% of spermatocytes. No increase in dominant lethality was observed after treatment with ADR at doses up to 6 mg/kg, while the frequency after 6 Gy of radiation was 3.6%. Based on these results, ADR would be expected to be only a weak inducer of balanced chromosomal rearrangements. Because ADR at 4.5 mg/kg was much weaker than 6 Gy of gamma-radiation at inducing chromosomal translocations, but just as effective at inducing sperm head abnormalities, the level of sperm head abnormalities is not indicative of balanced chromosomal rearrangements induced in stem spermatogonia by cytotoxic agents.

Studies of BCR and ABL gene rearrangements in chronic myelogenous leukemia patients by conventional and pulsed-field gel electrophoresis using gel inserts

Continual monitoring of the presence of the Philadelphia (Ph) chromosome in patients with chronic myelogenous leukemia (CML) is important for diagnosis as well as evaluation of therapy response of these patients. Because the Ph chromosome has been characterized molecularly to involve a reciprocal translocation between the ABL and BCR genes, there is an increasing interest in the use of molecular probes to detect chromosomal rearrangements in this disease. While rearrangements involving the bcr region of the BCR gene can be detected by conventional gel electrophoresis (CGE), detection of those involving ABL generally requires pulsed-field gel electrophoresis (PFGE). Currently, however, CGE and PFGE require different methods of cell preparation, with isolated DNA used in CGE and gel inserts containing whole cells used in PFGE. In this study, we show that the gel-insert method of DNA preparation can be adapted for use in CGE with slight modification of the gel-running conditions. The advantages of this method are demonstrated by studying both bcr and ABL rearrangements in bone marrow and peripheral blood samples of CML patients. Furthermore, we report a novel finding that chromosomal breakpoints in the ABL gene of CML patients occur predominantly between exons 1b and 1a.

Mutagen sensitivity and cancer susceptibility. Report of a cancer-prone family

A cancer-prone family was studied to determine if certain chromosomal abnormalities might have predisposed members to develop diverse types of malignancies. The types of neoplasia that occurred in this family included cancers of the breast and stomach, multiple myeloma, dermatofibrosarcoma, Wilm's tumor, and leukemia; the latter three occurred in children at an early age. Peripheral lymphocytes from 13 family members were examined for the presence of constitutional chromosomal abnormalities, fragile sites, and mutagen sensitivity. Our data shows that all living members of this family who had cancers were hypersensitive to chromosome breakage induced by bleomycin. In contrast, neither constitutional chromosomal abnormality nor heritable type of folate-sensitive fragile site was observed in any member. The above findings suggest that genetic defects affecting chromosomal breakage and repair may be contributing factors for cancer development in several members of this family.

Structural analysis of the alpha-globin gene cluster in two Chinese families with alpha-thalassemias

The inheritance of alpha-thalassemia is determined by restriction endonuclease mapping in the members of two Chinese families with history of Hb H disease. One family carries the South East Asia (SEA) deletion in alpha-thalassemia-1 determinant and the nondeletion mutation in alpha-thalassemia-2 determinant. The other family carries the SEA deletion in alpha-thalassemia-1 determinant and the leftward deletion in alpha-thalassemia-2 determinant. Direct analysis of the genetic defects by gene mapping technique is the most reliable method for detecting minor forms of alpha-thalassemia and provides valuable information for genetic conseling in affected families.

Cytogenetic investigation of chemically-induced aneuploidy in mouse spermatocytes

This paper discusses a test system in which mouse spermatocytes are analyzed for aneuploidy induction after mice are treated with various agents. Included in this report are methods and procedures of the assay, criteria for determination of aneuploidy induction, considerations for dose-response and stage-specific actions of agents that cause aneuploidy, and finally, advantages and disadvantages of this test system.

The myeloperoxidase gene is translocated from chromosome 17 to 15 in a patient with acute promyelocytic leukemia

This study demonstrates that a differentiation-specific gene, the myeloperoxidase (MPO) gene, is translocated in a patient with acute promyelocytic leukemia (APL). The MPO gene recently has been mapped to chromosome #17, close to the breakpoint involved in the t(15;17) commonly seen in APL. By in situ hybridization, we showed that this gene was translocated from chromosome #17 to #15 in an APL patient. Although the significance of this translocation remains unclear, MPO is known to be highly expressed in APL. The causal relationship between the high expression and translocation of this gene requires further investigation.

The localization of the human myeloperoxidase gene is in close proximity to the translocation breakpoint in acute promyelocytic leukemia

The human myeloperoxidase (MPO) gene has recently been cloned in our laboratory. Southern blot hybridization of our MPO cDNA to DNA from a somatic cell hybrid clone panel revealed that the MPO cosegregated with human chromosome 17. In situ hybridization mapped the MPO gene to chromosome 17q22-24. Although this location is close to the translocation breakpoint which occurs in acute promyelocytic leukemia (APL), t(15;17)(q22;q21-22), Southern blot hybridization with different restriction-digested genomic DNA samples from four APL patients did not reveal MPO gene rearrangement. However, RNA dot-blot hybridization showed that APL patients with the translocation expressed high levels of MPO mRNA. This observation raises the possibility that the high levels of MPO gene expression in APL could be due to the arrest of leukemic cells at a specific stage of differentiation or a consequence of the translocation.