[The detection of laryngeal carcinoma-associated antigens in tissue and serum using three mixed monoclonal antibodies against laryngeal cancer]

Laryngeal carcinoma-associated antigens in tissue and serum of patients with laryngeal carcinoma and normal adults were detected by using ABC and ELISA methods. The results showed that the positive rate rised from 80-86.6% to 97.7% by applying mixed monoclonal antibodies compared with single monoclonal antibody against laryngeal cancer. It was also found that the level of laryngeal carcinoma-associated antigens was much higher in serum of laryngeal carcinoma group than that of control group. The statistic difference was very significant (P < 0.01). The level was different with clinical types, stages and increased in line with the tumor growth. So it was suggested that the mixed monoclonal antibodies were sensitive and specific, which was considered as a useful tumor marker for diagnosis, monitoring clinial course and judging prognosis of patient with laryngeal carcinoma.

Light microscopic autoradiographic study of DNA synthesis in cecal epithelial cells of aging mice

The localization and activity of DNA synthesis of mouse cecal epithelia from prenatal Day 19 embryos to 12-month adults were investigated by light microscopic autoradiography after [3H]-thymidine injection in vivo. The cecal epithelial labeled cells with [3H]-thymidine were located at the lower half of the crypts, and the labeling index (LI) changed with the development of the cecum due to aging. A peak in the LI of absorptive cells was found at embryonic Day 19, but it decreased strikingly at the first postnatal day and then kept an almost constant value until 12 months. The LI of the goblet cells showed the highest value at fetal Day 19, decreased gradually with aging from the first postnatal day, and completely disappeared from 1 month onwards. The basal granulated cells were located only in the base of crypts, and the significant difference of LI was not found from embryonic Day 19 through 12-month adult. The results obtained in this study suggest that there are some differences of DNA synthesis among different kinds of cecal epithelial cells from embryonic stages to postnatal stages as a result of aging.

Nd: YAG laser lysis of the fibrinous membrane and remnant substance on the anterior surface of intraocular lens

PURPOSE

To determine the effects of Nd: YAG laser to disrupt the fibrinous membrane and remnant substance on the anterior surface of intraocular lens.

METHODS

Nd: YAG laser was applied on 23 cases of fibrinous membrane formation and 8 cases of remnant substance on the anterior surface of intraocular lenses (IOL) which had not responded well to steroid therapy. Eighteen cases were male and 13 female. The mean age was 49.7 years (range, 5 approximately 78 years). The interval between IOL implantation and laser therapy was 0.5 approximately 30 months in the fibrinous membrane cases and 3 approximately 10 days in the remnant substance cases. The energy applied was 0.8 approximately 3.0 mJ/exp. with 2 approximately 112 exposures. Mean follow-up period was 3.6 months.

RESULTS

Complications during therapy included only 2 cases of slight iris bleeding. Visual acuity after therapy was improved 1 line in 16 cases, 2 lines in 11 cases, 3 lines in 1 case, 4 lines in 1 case and 5 lines in 2 cases. No post-therapy complication was found.

CONCLUSIONS

Nd: YAG laser lysis is an effective alternative to remove the fibrinous membrane and remnant substances on the anterior surface of IOL.

Nonrandom chromosome abnormalities in short-term cultured primary squamous cell carcinomas of the head and neck

We report the finding of clonal chromosome abnormalities in short-term cultures from 44 squamous cell carcinomas of the head and neck region. Eleven tumors had gain or loss of the Y chromosome, sometimes one clone with +Y and another with -Y, as the sole anomaly, whereas the remaining 33 all carried structural rearrangements and usually were cytogenetically complex with multiple aberrations. The chromosomal bands most frequently involved were, in decreasing order of frequency, 8p11-q11, 1p11-q11, 3p11-q11, 11q13, 13p11-q11, 1p13, 5p11-q11, 7p11-q11, 15p11-q11, and 14p11-q11. Almost one-half of the breakpoints were located in centromeric or juxtacentromeric bands. Recurrent aberrations included i(8q), i(5p), i(1q), del(3)(p11-12), del(5)(p11), t(1;1)(p13;q25), and der(14;15)(q10;q10). To see whether the karyotypic features of head and neck squamous cell carcinoma differ depending on exact tumor site, we added to the present series our previously published 23 karyotypically abnormal head and neck squamous cell carcinomas that had been cultured in the same way as the tumors of the present series. In the ensuing correlation analysis, tumors of the oral cavity and oropharynx and hypopharynx were found to share many features: highly complex karyotypes were frequent, often containing isochromosomes such as i(8q) and i(5p), and also rearrangements of 11q13 (often as homogeneously staining regions) and loss of genetic material from the short arms of chromosomes 3, 13, 14, and 15 were repeatedly seen. Laryngeal carcinomas, on the other hand, often had simple karyotypic changes.

Upper-extremity Musculoskeletal Disorders in Keyboard Operators in Brazil: A Cross-sectional Study

This study sought to determine the prevalence of upper-extremity musculoskeletal disorders (UEMSDs) among keyboard operators in Sao Paulo, Brazil, and to compare this prevalence with that among other office workers. One hundred and thirty keyboard operators (mean age 33 years, 60 male/70 female) and 138 office workers (mean age 35 years, 82 male/56 female) from two computing centers were interviewed by a research assistant using a standardized questionnaire. Symptomatic subjects, defined as those who reported upper extremity pain or lost work time due to pain in the preceding 12 months, were examined by a rheumatologist. Mean (SD) lengths of employment were 9 (6) years for keyboard operators and 8 (6) years for office workers. Upper-extremity pain during the preceding seven days was reported by 66 keyboard operators (51%) and by 18 office workers (13%) (p < 0.0001); during the preceding 12 months, by 90 keyboard operators (69%) and by 26 office workers (19%) (p < 0.0001). UEMSDs were diagnosed following physical examination in 50 keyboard operators and in 12 office workers (9%) (p < 0.0001). Tenosynovitis was the most common disorder diagnosed among the keyboard operators (n = 23). Among the keyboard operators the prevalence of UEMSDs was significantly lower for males (p = 0.017, OR = 0.38, 95%CI = 0.17-0.86). The presence of a diagnosed UEMSD was significantly associated with duration of employment (p = 0.005) and lack of or insufficient rest breaks (p = 0.012). Keyboard operators had significantly more UEMSDs than did office workers. Strategies aimed at the reduction of repetitive strain injuries among keyboard operators, such as the provision of adequate work breaks, should be evaluated.

[Congenital pulmonary lymphangiectasis]

Six rare cases of congenital pulmonary lymphangiectasis were presented. The macroscopic characteristic of the lungs was honeycomb appearance due to extreme dilatation of the lymphatic spaces in the subpleural, interlobular, peribronchial and perivascular connective tissue. They had thin walls lined by endothelium. The dilated lymphatics may be due to congenital developmental defects or obstruction of major lymphatics, but they appeared to be associated only with pulmonary venous hypertension.

[Monitoring of lead content in foodstuff in China]

Lead contents in six kinds of foodstuff in China were monitored in 1992. Six hundred and three specimens of food were collected from the markets in Beijing, Shanghai, Jiangsu, Sichuan and Guangdong. Results showed that 96.2% of cereals, 84.4% vegetables, 97.6% dairy products, 96.0% eggs and, 100% meat and fish met the national food hygienic standards for lead allowable content. Daily dietary intake of lead of residents in six areas of China was lower than the provisional standard for Daily Allowable Intake of lead set by World Health Organization.

Ultrastructural and radioautographic studies on DNA synthesis in Leydig cells on aging mouse testis

A morphological observation and a radioautographic study were carried out to detect the ultrastructure and aging changes of DNA synthesis of the Leydig cells, whose structure has been observed and the area of the lipid droplets in the cytoplasm calculated. The observation by electron microscopy showed that Leydig cells contained abundant mitochondria and endoplasmic reticulum and that the area of the lipids in the cytoplasm changed with aging. Only little lipid droplets were found in embryonic and early postnatal stages, but they increased from postnatal two weeks onwards and no significant differences were found from 9 months to 21 months. The DNA synthesis in these cells was not vigorous at embryonic day 19, explored by light microscopic radioautography 1 hr. following a single injection of 3H-thymidine. The labeling index increased slightly before six months of age and reached its peak at 9 months. There was no significant difference found in the number of labelled cells from that time on. A relatively high level was maintained at adult and senescent periods. Our results demonstrate that the generation of the Leydig cells contained plentiful lipid droplets was vigorous at adult and senescence.

Urinary Phenylglyoxylic Acid Excretion after Exposure to Ethylbenzene among Solvent-exposed Chinese Workers

Factory surveys were conducted in the second half of work weeks on 360 solvent workers (202 men and 158 women) and 281 controls in China. Monitoring personal exposures showed that ethylbenzene exposure was low (geometric mean 1.8 ppm) and was accompanied by coexposure to toluene (1.5 ppm) and three xylene isomers (6.7 ppm). Urine samples collected at the end of the eight-hour shift were analyzed for phenylglyoxylic and mandelic acids by high-pressure liquid chromatography at 257 nm. Despite the low level of the exposures, a significant correlation was observed between ethylbenzene exposure and urinary phenylglyoxylic acid, with high (0.6-0.7) correlation coefficients, suggesting that urinary phenylglyoxylic acid is a good marker of occupational exposure to ethylbenzene. Mandelic acid also correlated with ethylbenzene exposure, but with much smaller coefficients (0.2), possibly because the method employed was more sensitive to phenylglyoxylic acid than to mandelic acid.

Visual rehabilitation in low vision patients with aging macular degeneration

Using optical visual aids, visual rehabilitation was performed in 14 cases (25 eyes) for low-vision patients with aging macular degeneration (AMD). With distance aids, visual acuity improvements were recorded for 24 eyes (95 percent) out of 25 eyes. Twelve eyes (48 percent) achieved vision equal to or better than 0.4. Utilizing near visual aids, the near visual acuity for all eyes (100 percent) were improved. Thirteen eyes (52 percent) received near vision equal to or better than 0.5. Ten patients were able to read No. 5 equal to or better than 0.5. Ten patients were able to read No. 5 Chinese print (corresponding visual angle is 0.67 at 30 cm of reading distance). The reading success rate was 71.4 percent. The results suggest that the application of visual aids is an effective method to improve the distance and near visual acuity of low vision patients with AMD.

Genomic structure and chromosomal localization of processed pseudogenes for human RBP-Jk

The functional gene for human recombination signal sequence-binding protein (RBP-Jk) and corresponding processed psudogenes have been isolated from various species, such as Drosophila, Xenopus, mouse, and human. Here we report the isolation of another two genomic pseudogenes of human RBP-Jk, named K2 and K7, from a cosmid library of Hela cells. The nucleotide sequences of both genes exhibited more than 95% homology to the functional human gene for RBP-Jk. Moreover, they did not contain any intron sequences and were interrupted by several stop codons in all frames. In situ hybridization demonstrated that the pseudogenes, K2 and K7, were localized at chromosomes 9p13 and 9q13, respectively. Their physical maps differed from those of the true functional gene and of the pseudogenes reported previously by Amakawa et al. (1993).

[Argon laser photocoagulation in the treatment of central serous chorioretinopathy]

Thirty-six cases (41 eyes) with central serous chorioretinopathy were treated by using argon laser photocoagulation. The results showed that the number of eyes with vision equal to or more than 1.0 increased from 7 (17.1%) pre-laser to 26 (63.4%) post-laser, while the number of eyes with vision less than 1.0 decreased from 25 (61%) pre-laser to 6 (14.6%) post-laser. The subretinal fluid was almost entirely absorbed from 1 week to 1 month after, and central fovea reflex could be seen in some cases. The results indicate that the vision prognosis is strongly related to the duration of the disease, but the direction of leakage to the fovea, the distance between the leakage and the fovea, and the dimension of sensory retina detachment are factors which weakly affect the post-laser vision.

Modulation of cytochrome P450 activities by 7,8-benzoflavone and its metabolites

7,8-Benzoflavone(ANF) is a potent in vitro inhibitor of CYP1A2 but is an in vitro activator of CYP3A4. We have investigated the inhibition of caffeine 3-demethylation by metabolites of ANF as well as ANF by human liver microsomes. ANF was the most potent among all the compounds tested. Metabolites of ANF with dihydrodiol substitution at positions 5,6 or 7,8 showed less inhibitory activity. These results suggest that ANF lies in the most appropriate orientation to the active site of CYP1A2. The activation of CYP3A4 enzyme activities by ANF and its metabolites was also investigated. Testosterone 6 beta-hydroxylation mediated by CYP3A4 was stimulated by ANF and metabolites with substitutions at positions 5,6 or 7,8. Hydroxy ANF metabolites, however, decreased the testosterone 6 beta-hydroxylation.

[Treatment of hypertensive intracerebral hematoma by CT-directed puncture aspiration and negative-pressure drainage--analysis of 120 cases]

Puncture aspiration and negative-pressure drainage have been performed in 120 patients with hypertensive intracerebral hematoma. The results demonstrated that the CT-directed location method designed by us, based on Matsumoto and Hondo, s location method, is simple, practicable, very accurate and less. When intracranial CT and clinical manifestations of hematoma are comprehensively analyzed, an operative indication can be correctly selected. Depending on CT manifestations and pathological changes, the selected operative time is 48h or so. Of the 120 patients which underwent this operation, only 31 have died. The mortality rate is 25 percent. The effect of the therapy is satisfactory.

Synthesis and Characterization of Molybdenum Carbide Clusters Mo n C 4 n , ( n = 1 to 4)

Laser radiation (XeCl laser, 308-nanometer wavelength) focused into a cell containing Mo(CO)(6) vapor produced ultrafine particles in the extended waist of the laser beam. Negative ion mass spectrometry revealed molybdenum carbide cluster ions with a stoichiometry MonC4n (n = 1 to 4). The MonC4n(-) (n = 2 to 4) ions are completely unreactive with NH(3), H(2)O, and O(2), suggesting structures in which the molybdenum atoms are unavailable for coordination to additional ligands. Collision-induced dissociation studies of these anions show the loss of MoC(4) units as the main fragmentation pathway. This observation, together with the lack of addition reactions, provides a basis for structures in which a planar cluster of two, three, or four molybdenum atoms is surrounded by, and bonded to, carbon dimers.

[Studies on the effect of deltamethrin bath treatment of hamsters infected with Leishmania donovani for interrupting kala-azar transmission]

Phlebotomus chinensis were fed respectively on two groups of Cricetulus barabensis infected with Leishmania donovani, of which one group had received deltamethrin bath and the other was not treated with insecticide bath. The results showed that all the sandflies in the former group died within 24 hours, while those in the latter group had a high survival rate. Among the 165 sandflies examined, 114 (69.1%) became infected. The promastigotes not only developed well in the midgut, but also invaded esophagus, pharynx and proboscis. In the control group, the mortality of sandflies in 24 hours was 5.1% (3/59). According to the data obtained in the present study, the authors consider that insecticide bath treatment of infected domestic dogs in endemic villages could be used for interrupting kala-azar transmission.

Exposure of workers to a mixture of toluene and xylenes. I. Metabolism

The urinary excretion of hippuric acid and methylhippuric acid was studied in workers (233 subjects; 122 men and 111 women) exposed to toluene and xylenes in combination and in non-exposed controls (281 subjects; 141 men and 140 women) recruited from the same factories or factories of the same regions. Smoking and drinking habits of the subjects were obtained by medical interviews. From each worker, one urine sample was collected at the end of a shift and analysed for hippuric and methylhippuric acids by high performance liquid chromatography. Air samples for the estimation of toluene and xylenes were collected with diffusive personal samplers. There was a linear correlation between the time weighted average exposure either to toluene or xylene isomers and the concentrations of hippuric acid or methylhippuric acid isomers in urine. Essentially no difference was found in the correlation between quantitative exposure and excretion in the three xylene isomers. Comparison of the slopes of regression lines indicated the absence of metabolic interaction between toluene and xylenes at the measured concentrations. The metabolism of toluene and xylenes was significantly reduced among smokers or drinkers compared with non-smokers and non-drinkers.

[Laser treatment for the membranous cataract: the significance of pre-laser interferometric acuity]

Laser interferometer was used for the detection of interferometric acuity before and after membranous cataract disruption by Q--switched Nd: YAG laser in 23 patients (23 eyes). There was no significant difference between the interferometric acuity before and after laser surgery (p < 0.05). The postoperative corrected acuity was related positively to the preoperative one (p < 0.05). 65.2% of the eyes had a postoperative corrected acuity better than the postoperative interferometric acuity. These results show that laser interferometric acuity is a valuable method in the evaluation of postoperative visual acuity, but false negative and false positive ones should be considered under some circumstances. The interferometric acuity can be affected by aphakia (high refractive error).

Site and mechanism of behavioral tolerance to cocaine: a study of dopamine release in Wistar-Kyoto and spontaneously hypertensive rats

Wistar-Kyoto and spontaneously hypertensive rats received i.v. infusions of cocaine hydrochloride (60 mg/kg per day) for 3, 7, and 14 days, or saline for 7 days. Acute cocaine challenge (40 mg/kg, s.c.) was given to treated and control rats 24 hr after the termination of each infusion period. There were no strain differences in brain levels of cocaine during cocaine infusion, nor after cocaine challenges. There were no strain differences in resting levels of [3H]dopamine release. Release of [3H]dopamine decreased in nuclei accumbens of 7- and 14-day cocaine-infused animals. Release of [3H]dopamine was maximal in both brain regions 2 hr after acute cocaine challenge. After 14 days of cocaine infusion, cocaine challenge in both strains reduced [3H]dopamine release in the nucleus accumbens, but not in the striatum; the reduction being greater in Wistar-Kyoto rats. The behavioral tolerance which accompanies similar cocaine infusion regimens may be related to striatal "tolerance" to cocaine-induced dopamine release.

Effects of passive smoking on respiratory illness from birth to age eighteen months, in Shanghai, People's Republic of China

The objective of this study was to evaluate the effects of exposure to nonmaternal, passive household cigarette smoke on the incidence of respiratory illness (bronchitis and pneumonia) among children from birth through age 18 months in the Lu-Wan District, Shanghai City, People's Republic of China. A secondary objective was to evaluate the effects of other environmental factors, such as the fuel used for cooking and whether the child was breast fed, on the incidence of respiratory illness. The total daily cigarette consumption of family members was used to estimate exposure to passive smoke. The relative risks of exposure to passive cigarette smoke on the incidence of respiratory illness were 1.3, 1.7, and 2.0 for children living in households with members who smoked 1 to 9, 10 to 19, and 20 to 39 cigarettes per day, respectively, compared with the risks for children living in nonsmoking households (p for trend = 0.0002). These effects did not change materially when potential confounding factors were controlled. Children who were not fed human milk had a 1.8-fold increased risk of respiratory disease at each level of exposure to passive cigarette smoke evaluated, in comparison with children who were fed human milk for at least 1 month.

Excretion of methylhippuric acids in urine of workers exposed to a xylene mixture: comparison among three xylene isomers and toluene

The correlation between exposure to three xylene isomers and resulting urinary excretion of corresponding methylhippuric acid (MHA) isomers was studied among 175 Chinese workers of both sexes who had been predominantly exposed to xylenes (exposure to xylenes accounting for 70% or more of the total exposure on a ppm basis). Nonexposed controls (281 men and women) were also studied to define the background level of MHAs in urine. The solvent exposure of xylene-exposed workers during their workshift was monitored by diffusive sampling of breathing zone air, and MHAs in shift-end urine were determined by high-performance liquid chromatography. Regression analysis showed that the concentration of each MHA isomer correlated significantly with the time-weighted average intensity of exposure to the corresponding xylene isomer, and therefore the correlation between the sum of three xylene isomers in air and that of three MHA isomers in urine was also significant; the slope of the regression line was essentially the same among the three isomers. The calculated regression line suggested that the urinary MHA level after hypothetical exposure to xylenes at 100 ppm will be somewhat less than the proposed biological exposure index and biological tolerance value. Two social habits of smoking and drinking in combination suppressed the conversion of xylenes to MHAs in male workers.

Dose-dependent increase in subjective symptoms among toluene-exposed workers

A factory survey on dose-response relationship in toluene toxicity was conducted in 1985-1989 in four cities in China. The examination items consisted of personal diffusive sampling for TWA exposure measurement, questionnaires on subjective symptoms, hematology and serum biochemistry, and clinical examination including simple neurology tests. Hippuric acid was also determined in urine samples collected at the end of the shift. With selection criteria that (1) complete results were available on all study items and (2) valid toluene exposure data (i.e., toluene shared 90% or more of the exposure) were obtained for the exposed, 452 toluene-exposed workers (206 men and 246 women; toluene exposure at 24.7 ppm as GM) and 517 nonexposed controls (246 men and 271 women) were selected. The subjective symptoms increased in close association with the intensity of exposure to toluene; the threshold concentration appeared to exist at 100 ppm in the case of symptoms during work, and it might be at 50-100 ppm when symptoms off work were evaluated. During the work with exposure at higher concentrations, various symptoms possibly related to CNS or local effects (e.g., eyes, nose, and throat) were complained, and dizziness and floating sensations were identified as typical symptoms with significant dose-response relationship. Several symptoms persisted off work, most of which were apparently related but not necessarily limited to CNS effects. Hematology and serum biochemistry were essentially negative.

Effects of smoking and drinking on excretion of hippuric acid among toluene-exposed workers

In order to investigate possible effects of smoking and drinking on the metabolism of toluene in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to toluene. There was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits.

Complementary deoxyribonucleic acid cloning and expression of a human liver uridine diphosphate-glucuronosyltransferase glucuronidating carboxylic acid-containing drugs

A cDNA clone, designated UGT2B7 variant, encoding a 529-amino acid human liver microsomal uridine diphosphate-glucuronosyltransferase (UGT) was isolated from a lambda gt11 human liver cDNA library. UGT2B7 variant synthesized in COS-7 cells was screened for activity toward a range of clinically used drugs and other xenobiotics. The expressed enzyme glucuronidated several carboxylic acid-containing nonsteroidal antiinflammatory agents including, in order of relative substrate activity, naproxen, ketoprofen, ibuprofen, fenoprofen, tiaprofenic acid, benoxprofen, zomepirac, diflunisal and indomethacin. Additionally, the stereoselectivity of ketoprofen, naproxen (S/R ratio approximately unity) and ibuprofen (S/R ratio 1.62) glucuronidation by the UGT2B7 variant was shown to differ. Two other carboxylic acid-containing drugs (clofibric acid and valproic acid) and a limited range of drugs containing an alcohol or phenolic functional group were also glucoronidated by expressed UGT2B7 variant. The deduced amino sequence of UGT2B7 variant was shown to differ only in one amino acid (tyrosine for histidine at position 268) from a previously published uridine diphosphate-glucuronosyltransferase cDNA, UGT2B7. Like the previously reported enzyme, this variant efficiently glucuronidated hyodeoxycholic acid, estriol, 4-hydroxyestrone and 2-hydroxyestriol. It is, therefore, apparent that UGT2B7 variant has the capacity to glucuronidate with a degree of specificity both endogenous compounds and xenobiotics. Preferred substrates for UGT2B7 variant include xenobiotic carboxylic acids, polyhydroxylated estrogens and hyodeoxycholic acid.

Biopathologic characteristics of DNA content in crypt cells of transitional mucosa adjacent to carcinomas of the rectum and rectosigmoid

The transitional mucosa (TM) adjacent to carcinomas of the large bowel shows histologic and mucin histochemical changes that may indicate premalignant change and may be of prognostic value after radical resection. In this study, 10 anterior resection specimens from patients with carcinomas of the rectum and rectosigmoid were used to compare the nuclear DNA content in TM with those in cancer tissue and with those in nontransitional mucosa (N-TM; i.e., uninvolved mucosa remote from tumors showing normal histologic and mucin histochemical features). The nuclear DNA content was assessed using DNA image cytometry on Feulgen-stained sections. As compared with N-TM, crypts in TM contained greater numbers of cells, were elongated, and were more likely to be branched with marked sialomucin secretion, accompanied by a marked reduction in the normal sulfomucin content. The mean nuclear DNA content in the upper, middle, and lower thirds of crypts was significantly higher in TM than in N-TM, and the nuclear DNA content in TM exhibited no correlation to that in tumors. The results suggest that TM adjacent to carcinomas of the rectum and rectosigmoid has higher proliferative activity, providing further evidence that TM may be an unstable premalignant change.

Effects of some natural products as components of Chinese herbal medicines on mammary gland growth and function in mice

As a possible step to evaluate the role in the mammary glands of the scales of Guanshanjia, the fruits of Lulutong and the seeds of Wangbuliouxing, which are the natural products used widely as the components of herbal medicine in China for the improvement of lactation and the therapy of breast disorders, the effects of these agents on mammary gland growth and function were studied in female mice. The chronic administration of each agent in drinking water improved several parameters; however, the mode of action differed markedly among agents. The results indicate the necessity of acquiring enough knowledge of the characteristics of each agent for the efficient prescription of herbal medicine as well as the single use of the agent.

[Affinities of PBPs of enterococci to cefepime and ampicillin]

The beta-lactam resistance of genus Streptococcus has been explained by the low binding affinity of penicillin-binding proteins (PBPs) to the drug. This study was carried out to resolve the mechanisms of resistance to beta-lactam antibiotics in the species of genus Enterococcus by means of binding affinities of PBPs. Streptococcus pyogenes, Enterococcus faecalis, Enterococcus faecium and Enterococcus avium were employed as assay microbes. Cefepime (CFPM) and ampicillin (ABPC) were used as representatives of cephems and penicillins, respectively. All the PBP fractions of S. pyogenes manifested high binding affinities to CFPM and ABPC, whereas PBPs 1 and 4 of E. faecalis showed high binding affinities to ABPC but not to CFPM. In E. faecium, PBPs of an exceptionally penicillin-susceptible strain manifested a high binding affinity to ABPC, but PBPs 5 and 6 showed low affinities to CFPM. beta-lactam resistant strains of E. faecium possessed PBPs 5 and 6 with low binding affinities to CFPM and ABPC. All the fractions of PBPs but PBP 1 in E. avium showed low binding affinities to CFPM. Although all the PBP fractions but PBPs 3 and 6 manifested high binding affinities to ABPC, PBPs 3 and 6 showed low binding affinities to ABPC. A strain of E. avium, which is susceptible to ABPC but moderately resistant to CFPM, lacked PBP 6. In conclusion, the resistance of E. avium to CFPM is based upon low binding affinities of the many fractions to this drug, and ABPC resistance is based upon PBPs 3 and 6 with low binding affinities to ABPC.

Cocaine elevates striatal dopamine efflux in spontaneously hypertensive and Wistar-Kyoto rats

The effects of acute cocaine administration on central dopaminergic systems were examined in the striata of spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats with the use of an in vivo microdialysis technique. Increased extracellular levels of dopamine were observed for 45 to 75 minutes following acute cocaine administration in both halothane-anesthetized and conscious SHR and WKY. However, no significant differences were noted between anesthetized and conscious SHR and WKY in either baseline levels or cocaine-induced changes in extracellular levels of dopamine and its metabolites. A positive, linear correlation between extracellular levels of dopamine and cocaine was demonstrated for the 60-min period following acute cocaine administration in both SHR and WKY. The slopes of the linear regression plots obtained from the data of each 15-min sample was slightly, but significantly, higher in conscious SHR than in conscious WKY. The present results suggest a transient and dose-related stimulation of striatal dopamine release following acute cocaine administration and a linear relationship between striatal extracellular levels of dopamine and cocaine in both SHR and WKY.

Comparisons of cocaine receptors in brain regions from WKY and SHR

Both high- and low-affinity sites for [3H]cocaine binding were present in the striatum, hippocampus, olfactory tubercle, and hypothalamus of WKY and SHR. In the striatum, Kd values of both sites and the Bmax value of the high-affinity site were lower in SHR than in WKY rats. In the hippocampus, only the Kd value of the high-affinity site was lower in SHR than in WKY rats. However, there were no differences in Kd or Bmax values between strains in the olfactory tubercle or hypothalamus. The differences in characteristics of [3H]cocaine binding in WKY and SHR may provide a neurochemical basis for the different responses of the two strains to cocaine administration.

[Effect of Astragalus membranaceus on erythrocyte sodium content and sodium transport in the coronary heart disease]

The purpose of this study was to investigate the effect of Astragalus membranaceus (AM) on erythrocyte sodium content and sodium transport in the coronary heart disease(CHD). 67 cases of CHD was randomly divided into treatment group (TG) and control group (CG), TG (45 cases) were treated with AM intravenous 24 g/d infused into 5% glucose 250 ml, CG (22 cases) with 5% glucose 250 ml. After a curable stage of 14 days, results showed that the erythrocyte sodium content was markedly decreased and the sodium pump activity was significantly increased (P less than 0.01 respectively) in TG; but no significant difference in membrane permeability to sodium was observed. There were no difference in erythrocyte sodium content and sodium transport in CG. It was suggested that AM had the effects to increase erythrocyte activity of sodium pump.

Prevalence of hepatitis B virus infection markers among factory workers in Beijing, China

Nearly 1,000 serum samples were obtained from apparently healthy workers of both sexes in various factories in Beijing during 1988-1989 and were examined for hepatitis B virus infection markers by radioimmunoassay. The overall prevalence (all ages and both sexes combined) of cases positive for HBsAg, anti-HBs and anti-HBc were 3.7%, 36.6% and 37.7%, respectively and the rate of those negative to any of the three markers studied was 56.1%. The infection rate was lower than the values reported early in the 1980s for Beijing populations or the values for populations in other parts of China.

Visual rehabilitation in low vision patients with age-related macular degeneration

Using optical visual aids, visual rehabilitation was performed in 14 low vision patients (25 eyes) with age-related macular degeneration. With distance aids, visual acuity improvement appeared in 24 eyes (95%) out of the 25 eyes. Twelve eyes (48%) obtained a visual acuity equal to or better than 0.4. With near visual aids, near acuity of all eyes (100%) was improved. Thirteen eyes (52%) got the near vision equal to or better than 0.5. Ten patients could read No. 5 Chinese Reading Card. The reading success rate was 71.4%. The results suggest that application of visual aids is an effective method to improve the distant and near visual acuity of low vision patients with AMD.

[Visual rehabilitation in low vision patients with aging macular degeneration]

Using optical visual aids, visual rehabilitation were performed in 14 cases (25 eye) of low vision patients with aging macular unity of all eyes (100%) was improved. Thirteen eyes (52%) got the near vision equal to or better than 0.5. Ten patients could read No. 5 Chinese Reading Card. The reading success rate was 71.4%. The results suggest that application of visual aids is an effective method to improve the distance and near visual acuity of low vision patients with AMD.

Endogenous retroviral LTR DNA sequences as markers for individual human chromosomes

The human genome carries multiple copies of sequences related to endogenous retroviral genomes that include long terminal repeat (LTR) sequences. We used the LTR of one such viral genome, called HERV-A, as a probe in Southern analysis to examine the distribution profiles of the hybridizing DNA in the genomes of twelve human x rodent hybrid cell lines carrying one or a few human chromosomes, and in the DNA samples prepared from six sorted, individual chromosomes. The HERV-A sequence was found to be widely distributed among different chromosomes and the Southern patterns for chromosomes 5, the X, and the Y, each obtained in duplicate from independently prepared cell lines or sorted chromosomes, were matched. Chromosome-specific Southern profiles can be used to monitor chromosomes in hybrid cells or to characterize chromosome aberrations, such as deletions.

[Studies on left ventricular performances pre- and post-percutaneous balloon valvuloplasty in 57 cases]

The left ventricular performances (LVP), assessed by two dimensional echocardiography (2 DE) pre- and post-percutaneous balloon mitral valvuloplasty, showed a good linear correlation with those by angiography, the correlative coefficients being 0.94 (left ventricular volume), 0.93 (ejection fraction) and 0.90 (stroke volume), respectively. The results showed that 2 DE may be used in follow-up study of left ventricular performances instead of angiography. Accordingly, it was found that the short-term (6-10 months) effect in LVP of 57 cases post-PBMV assessed by 2 DE in comparison with that pre-PBMV was statistically very significant (t = 3.73-12.92, P less than 0.001); the long-term (12-42 months) effect of 88 cases post-PBMV evaluated by 2 DE compared with that pre-PBMV was statistically very significant (t = -3.73-10.46, P less than 0.001); all these showed that both the short-term and long-term cardiac functions post-PBMV had markedly improved. However, there was a significant difference in statistics (t = 2.41-3.14, P less than 0.05-0.001) between the short-term and long-term cavity area) and radionuclide angiography both during early diastole (r = 0.94) and atrial systole (r = 0.90). The above results were better than those obtained from pulsed Doppler (E area/Total, A area/Total) and radionuclide angiography: during early diastole (r = 0.78) and atrial systole (r = 0.76). Color Doppler can be used as a new method for assessing the pattern of left ventricular filling.