Cystic echinococcosis in the Xinjiang/Uygur Autonomous Region, People's Republic of China. I. Demographic and epidemiologic data

Demographic and epidemiologic data on those factors potentially related to the prevalence and transmission of hydatid disease caused by Echinococcus granulosus were collected in 1987 from each household in 85 villages in the two communities of Yuanhucun and Ershilidian within Hutubi County in the Xinjiang/Uygur Autonomous Region, PRC, with additional questionnaire data collected from approximately 40 households randomly selected from each of 16 villages within those communities. Yuanhucun and Ershilidian represent a combined area of 522.7 square km, and have 4,853 households with 25,684 inhabitants. Of those households, 69.9% are of the Han ethnic group, 22.1% Hui, 5.3% Uygur, and 2.7% Kazak. The total number of animals censused included 4,169 dogs, 41,369 sheep, 3,673 goats, 2,639 cattle, 5,400 pigs, 1,472 horses, and 59 donkeys. Levels of infection of the causative organism of cystic hydatid disease in various hosts were: dogs harboring Echinococcus granulosus tapeworms - 63 (16.2%) positive of 390 examined in 16 villages; domestic animals with hydatid cysts - 1,593 (88.6%) sheep of 1,797 examined, 69 (56.1%) of 123 goats, and 47 (94.0%) of 50 cattle; and 15 surgeries in inhabitants from 85 villages during the last 16 months prior to completion of the survey (annual case rate of 43.8/100,000). Questionnaire data collected from inhabitants in 16 villages showed that about 82% of the families owned at least one dog and 78% owned sheep. Of those families with sheep, most (84%) killed sheep for meat at least periodically, 76% had seen hydatid cysts in liver or lungs of butchered animals, and 77% routinely gave raw offal to their dog.(ABSTRACT TRUNCATED AT 250 WORDS)

Endothelin-1 induces intracellular calcium rise and inositol 1,4,5-trisphosphate formation in cultured rat and human glioma cells

The effects of endothelin-1 (ET) on the signal transduction in rat and human glioma cell line cells have been investigated. ET was found to initiate the increase of intracellular calcium ([Ca2+]i) levels in both C6 and A-172 cells, which was concurrent with the formation of inositol 1,4,5-trisphosphate (IP3(1,4,5)). In the presence of [ethylenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA) in the incubation media, the duration of the intracellular calcium response was reduced, indicating that the ET-induced increase of intracellular calcium in glioma cells may be mediated by a dual mechanism, intracellular calcium mobilization and influx of extracellular calcium. These results suggest that ET may also act as a neuropeptide in the central nervous system.

Repetitive DNA sequences linked to the sea urchin spec genes contain transcriptional enhancer-like elements

The 5' flanking DNA of three related Strongylocentrotus purpuratus genes, Spec1, Spec2a, and Spec2c, were analyzed with respect to structure and cis-regulatory activity. The structural features of DNA sequences upstream of the first intron were highly unusual and implicated certain regions as sites of coordinate control for gene expression. By aligning the genes with a common upstream 600-bp repetitive DNA sequence element, termed RSR, it was shown that a conserved DNA block of approximately 800 bp extended from the 3' end of the first exon to the 5' end of the RSR element. In Spec2a, the conserved sequence block was a continuous stretch of DNA, but in Spec1 and Spec2c, 2.5 to 3 kb of inserted DNA bounded by short direct repeats interrupted the conserved sequence block, thus changing the relative placement of the RSR element and other 5' flanking DNA. Deletion of XhoI fragments containing the 5' half but not the 3' half of the RSR element resulted in a significant decrease in chloroamphenicolacetyl transferase (CAT) activity when Spec-CAT reporter gene fusion plasmids were injected into Lytechinus pictus eggs. These results strongly suggested, but did not prove, that the sequences held in common among the XhoI fragments, that is, the 5' half of the RSR elements, were responsible for the decrease in CAT activity. The Spec2a gene was particularly sensitive to deletions of the XhoI fragment containing the 5' half of the RSR element. The deleted element had several enhancer-like properties when inserted back into various test plasmids: it could be positioned in locations different from the transcriptional start site; in some but not all cases, it could be made to work in the reverse orientation; and it could drive expression of the CAT gene using an SV40 promoter or cryptic promoter elements. These findings suggested that an enhancer-like element important for Spec gene expression was contained within a repetitive DNA sequence. Genomic DNA blots suggested that there are many more of these RSR elements than there are Spec genes.

Measurement and study of the nose and face and their correlations in the young adult of Han nationality

The measurement of 13 items in the face and nose of 220 young adults (110 males and 110 females) of the Han nationality between the ages of 18 and 21 years has been done in the Henan Province of China. The means and standard deviations have been obtained, and the significant differences in many items between males and females have been proved. Some items influencing outer nasal shape have been analyzed. The correlations between nose height, nose length, and morphologic facial height and physiognomic facial height have been discussed. The ratio and amount of nasal breadth to facial breadth and nasal breadth to interocular breadth have been compared and analyzed, and the differences among the different races and between the sexes have been explained.

Periodontal conditions in elderly people of Shanghai, People's Republic of China, in 1986

In a stratified multi-stage random sample, 1600 persons of 60 years and older in Shanghai, People's Republic of China, were investigated for periodontal conditions using the CPITN method. Periodontal conditions seemed to deteriorate steadily but rather slowly with increasing age. In the older age groups, there was a trend for an increased proportion of both subjects and sextants scoring CPITN code 4 (deep pockets). The increase in tooth loss with increasing age was more clearly visible: increasing percentages of edentulousness and decreasing mean numbers of teeth remaining in dentate subjects.

Simulation and application of the distorted ZOLZ patterns from dislocations in Si

The previously reported distorted zeroth-order fringes in a bright-field Tanaka pattern from a dislocated region in silicon have been computer simulated and the experimental and the many-beam calculated patterns agree well. Calculations are carried out for nine distinct cases of edge, screw and 60° dislocations in a silicon crystal. The general usefulness of the distortion of the ZOLZ pattern in determining geometrical properties of a dislocation is discussed.

Isolation of an efficient actin promoter for use in rice transformation

We have characterized the 5' region of the rice actin 1 gene (Act1) and show that it is an efficient promoter for regulating the constitutive expression of a foreign gene in transgenic rice. By constructing plasmids with 5' regions from the rice Act1 gene fused to the coding sequence of a gene encoding bacterial beta-glucuronidase, we demonstrate that a region 1.3 kilobases upstream of the Act1 translation initiation codon contains all of the 5'-regulatory elements necessary for high-level beta-glucuronidase (GUS) expression in transient assays of transformed rice protoplasts. The rice Act1 primary transcript has a noncoding exon separated by a 5' intron from the first coding exon. Fusions that lack this Act1 intron showed no detectable GUS activity in transient assays of transformed rice protoplasts. Deletion analysis of the Act1 5' intron suggests that the intron-mediated stimulation of GUS expression is associated, in part, with an in vivo requirement for efficient intron splicing.

Isolation of an efficient actin promoter for use in rice transformation

We have characterized the 5' region of the rice actin 1 gene (Act1) and show that it is an efficient promoter for regulating the constitutive expression of a foreign gene in transgenic rice. By constructing plasmids with 5' regions from the rice Act1 gene fused to the coding sequence of a gene encoding bacterial beta-glucuronidase, we demonstrate that a region 1.3 kilobases upstream of the Act1 translation initiation codon contains all of the 5'-regulatory elements necessary for high-level beta-glucuronidase (GUS) expression in transient assays of transformed rice protoplasts. The rice Act1 primary transcript has a noncoding exon separated by a 5' intron from the first coding exon. Fusions that lack this Act1 intron showed no detectable GUS activity in transient assays of transformed rice protoplasts. Deletion analysis of the Act1 5' intron suggests that the intron-mediated stimulation of GUS expression is associated, in part, with an in vivo requirement for efficient intron splicing.

Brain drain and economic cycles with international migration: a case of minimum wage in the unskilled sector

"The purpose of this paper is to establish the existence of economic cycles in Rodriguez's descriptive growth model with brain drain. We guarantee limit cycles in the case of minimum wages in the unskilled sector. The expression, period and stability conditions of the economic cycle are explicitly given."

Genotoxic evaluation of chronic fluoride exposure: sister-chromatid exchange study

As part of a continuing investigation, this study was conducted to examine the genotoxic effects of chronic exposure to sodium fluoride (NaF) in drinking water on the frequency of sister-chromatid exchange (SCE) in the bone-marrow cells of male Chinese hamsters. Animals at about 3 weeks of age were randomly assigned to 6 groups, each with at least 3 hamsters, and were maintained on a low fluoride diet (less than 0.2 ppm F) throughout the experiment. At 4 weeks of age, the animals in groups I-V began to receive drinking water containing fluoride at concentrations of 0, 1, 10, 50 and 75 ppm, respectively. Group VI was treated with cyclophosphamide and served as the positive control. The animals were sacrificed at 24 weeks of age by cervical dislocation. The humeri and plasma were analyzed for fluoride content, which was found to increase with the increase in fluoride concentration in drinking water. Slides of chromosomes from bone-marrow cells were prepared and blindly examined for the frequency of SCE. The mean scores of SCE for the hamsters receiving drinking water containing F concentrations up to 75 ppm for 21 weeks ranged from 4.28 to 6.28 per cell, and were not significantly different from those of the negative controls (4.60-5.44/cell). The results indicated that chronic fluoride exposure had no effect on the frequency of SCE in Chinese hamster bone-marrow cells under the conditions of the present investigation.

Genotoxic evaluation of chronic fluoride exposure: micronucleus and sperm morphology studies

The purpose of this study was to investigate the genotoxic effects of chronic fluoride exposure on mammalian cells in vivo by use of the mouse bone-marrow micronucleus test and the sperm morphology methodology. Mice of genotype B6C3F1 were obtained at weaning and maintained on a low-fluoride diet (less than 0.2 ppm F) ad libitum throughout the experiment. The animals were randomly assigned to seven groups and given fluoride (as sodium fluoride) in concentrations ranging from 1.0 to 75 ppm in the drinking water. Negative (distilled water) and positive (cyclophosphamide) controls were included. After a 21-week treatment period, the animals were killed by cervical dislocation, and blood was obtained by cardiac puncture. Slides of femur marrow cells were prepared and blindly examined for the frequency of micronucleated polychromatic erythrocytes (MN-PCE). Slides of sperm from the cauda epididymides of the male mice were also prepared and similarly examined for morphological abnormalities. Weight of the testes was recorded, and the plasma, humeri, testes, and carcasses were saved for fluoride analyses. Analyses of bone and plasma fluoride confirmed the effective absorption of fluoride following ingestion. The frequency of MN-PCE, the count of abnormal sperm, and the weight of the testes for mice chronically exposed to fluoride, in doses ranging from approximately 0.3 to 23 mg/kg/day, were not significantly different from those of the negative control animals. The results of this study support the view that fluoride has no genotoxic effects.

[Isolation and fermentation conditions of polyvinyl alcohol-degrading enzyme producing strain]

A bacterium D8 strain which high efficiently degrading PVA was isolated from waste water of factory. The strain possesses the abilities of completely degrading 0.5 per cent of PVA (500, 1700) included in the culture medium for four days. It was identified Pseudomonas pseudoalcaligenes. Fermentation conditions of the strain have been investigated. The suitable medium consisted of PVA 1.5% (NH4)2SO40.1%, K2HPO4 0.24%, KH2PO4 0.04%, MgSO4.7H2O 0.035%, NaCl 0.01%, FeSO4 0.001%, yeast extract 0.15%, pH 7.5. The optimal condition for enzyme production are as follows: 250 ml shake filled with 30 ml medium, 30 degrees C, 160n/min incubation period 72 h. Under such conditions enzyme activity is highest.

Transcription of the Spec 1-like gene of Lytechinus is selectively inhibited in response to disruption of the extracellular matrix

The influence of the extracellular matrix (ECM) on differential gene expression during sea urchin development was explored using cell-type-specific cDNA probes. The ECM of three species of sea urchin, Strongylocentrotus purpuratus, Lytechinus variegatus and Lytechinus pictus, was disrupted with the lathrytic agent beta-aminopropionitrile (BAPN), which inhibits collagen deposition in the ECM and arrests gastrulation (Wessel & McClay, Devl Biol. 121: 149, 1987). The levels of several mRNAs (Spec 1, Spec 2, CyIIa actin, CyIIIa actin and collagen in S. purpuratus, and metallothionine, ubiquitin and LpS3 in L. pictus and L. variegatus) were compared in BAPN-treated and control embryos. These mRNAs accumulated normally during BAPN treatment, even though the embryos did not gastrulate. To determine if the expression of any gene product is sensitive to ECM disruption, a differential cDNA screen compared poly (A+) RNA from BAPN-arrested and control embryos in Lytechinus. A cDNA clone was isolated from this screen that represented a 2.1 kb mRNA that did not accumulate during BAPN treatment. Removal of BAPN resulted in the accumulation of this transcript coincident with the onset of gastrulation. This cDNA clone encodes a L. variegatus homologue of LpS1, recently demonstrated to be an ancestral homologue of the aboral ectoderm-specific Spec 1-Spec 2 gene family in S. purpuratus. Nuclear run-on assays in L. pictus suggested that transcriptional activity of LpS1 was selectively inhibited by BAPN treatment. Thus, although the accumulation of many gene products occurred independently of the embryonic collagenous matrix, the accumulation of LpS1 and LvS1 appeared to be mediated by the ECM.

Repeated haloperidol administration changes basal release of striatal dopamine and subsequent response to haloperidol challenge

The effects of acute or repeated administration of haloperidol on release of dopamine (DA) and homovanillic acid (HVA) from striata of awake rats were studied using a microdialysis probe. A single injection of haloperidol (1 mg/kg, i.p.) produced a time-dependent increase in DA and HVA in the perfusate. Comparative studies in rats anesthetized with 300 mg/kg of chloral hydrate given i.p. found that anesthesia decreased the basal release of DA, but not HVA, and significantly blocked haloperidol-induced increases in DA, while haloperidol-induced increases in HVA were not affected. Studies done in awake rats found that 21 repeated daily injections of haloperidol increased the basal release of DA, but not HVA. Subsequent challenge with haloperidol indicated a significant decrease in responsiveness to haloperidol-induced release of DA, but not HVA, in chronically dosed rats. These data suggest that repeated exposure to haloperidol causes a compensatory increase in extracellular DA release. That these compensatory changes may be associated with the increased therapeutic efficacy or extrapyramidal side effects of neuroleptics following repeated dosing warrants further study.

[Evaluation of coronary artery fistula using a color Doppler flow imaging technique]

Two unusual cases with coronary artery fistula were reported. The diagnoses were first made by color Doppler flow imaging and confirmed by selective coronary angiography and operation. In the first case, color Doppler revealed a continuous flow signal within the dilated left coronary artery and a turbulent jet within the right atrium. In the second case, color Doppler showed turbulent flow signals which could be traced from the proximal left coronary artery, along the left ventricular posterior wall and into the left ventricle. The high velocities at the site of drainage of fistula were recorded by the continuous-wave Doppler and the calculated pressure gradient confirmed that the abnormal flow was from the systemic circulation. We are of the opinion that color Doppler flow imaging is a reliable technique for detecting coronary artery fistula and the combination of color Doppler with continuous-wave Doppler is essential for evaluating the hemodynamics of the shunt flow.

The economic law of population distribution and migration

"The economic law of population distribution and migration has been studied chiefly based on the Chinese situation. The distribution and development of productive forces decide the distribution and migration of population, and in turn, the latter influences the former. The population distributions in three different stages of social development, namely agricultural, industrial and information society, are described. A new concept in population economics is introduced, i.e. population economic density, which is different from the concept of population density. The formula of population economic density is P(population)/R(resources). Many kinds of migration are analysed, and it is believed that the main efficient cause of migration is economy."

The transformation of the agricultural population and the urbanisation process in China

"Nine causes for the occurrence of surplus agricultural labour with the modernisation of agriculture have been identified. Several solutions to this problem are presented. Urbanisation of the agricultural population in a way suited to China's characteristics is necessary, important and possible." An example of labor saving through mechanization in Heilongjiang province is presented.

Efficient regeneration of transgenic plants from rice protoplasts and correctly regulated expression of the foreign gene in the plants

Rice is one of the most important crops in the world with 35% of the total population (over two billion people) depending on it as their source of food. It is therefore essential to develop efficient methods for the transformation and regeneration of rice plants in order to delineate the exact regulatory sequences responsible for gene expression and to transfer beneficial genes into this plant. Here, for the first time, we present definitive evidence for the regeneration of a large number of transgenic rice plants after introduction of the bacterial β-glucuronidase gene into rice protoplasts. The presence of integrated copies of this gene was detected in the genome of transgenic plants by DNA hybridization analysis. Furthermore, under the control of regulatory regions from a maize alcohol dehydrogenase sequence, β-glucuronidase gene expression was detected in the roots of transgenic plants. This expression was stimulated up to six fold under anaerobic conditions.

Dexamethasone-dependent inhibition of differentiation of C2 myoblasts bearing steroid-inducible N-ras oncogenes

ras proteins are localized to the plasma membrane where they are postulated to interact with growth factor receptors and other proximal elements in intracellular cascades triggered by growth factors. The molecular events associated with terminal differentiation of certain skeletal myoblasts are inhibited by specific polypeptide growth factors and by constitutive expression of transforming ras oncogenes. To determine whether the inhibitory effects of ras on myogenic differentiation were reversible and to investigate whether muscle-specific genes remained susceptible to ras-dependent repression in terminally differentiated myotubes, the murine myoblast cell line, C2, was transfected with a plasmid containing a mutationally activated human N-ras oncogene under transcriptional control of the steroid-sensitive promoter of the mouse mammary tumor virus long terminal repeat. Addition of dexamethasone to myoblasts bearing steroid-inducible ras oncogenes prevented myotube formation and induction of muscle creatine kinase and acetylcholine receptors. Inhibition of differentiation by dexamethasone occurred in a dose-dependent manner and was a titratable function of ras expression. In the presence of dexamethasone, myoblasts bearing steroid-inducible ras genes retained their dependence on exogenous growth factors to divide and exhibited contact inhibition of growth at confluent densities, indicating that the inhibitory effects of ras on differentiation were independent of cell proliferation. Removal of dexamethasone from N-ras-transfected myoblasts led to fusion and induction of muscle-specific gene products in a manner indistinguishable from control C2 cells. Examination of the effects of culture media conditioned by ras-transfected myoblasts on differentiation of normal C2 cells yielded no evidence for inhibition of differentiation via an autocrine mechanism. In contrast to the ability of N-ras to prevent up-regulation of muscle-specific gene products in myoblasts, induction of N-ras in terminally differentiated myotubes failed to extinguish muscle-specific gene expression. Together, these results suggest that oncogenic ras proteins reversibly activate an intracellular cascade that prevents establishment of the differentiated phenotype. The inability of ras to extinguish muscle-specific gene expression in terminally differentiated myotubes also suggests that ras may interfere with an early step in the pathway of myoblasts toward the differentiated state.

Stimulation of cAMP accumulation and superoxide production in human neutrophils and monocytes

The effect of sodium fluoride (NaF) on superoxide generation and cyclic adenosine monophosphate (cAMP) levels in human neutrophils and monocytes was investigated. NaF (greater than 10 mM) stimulated superoxide (O2-) production in both cell types in a time dependent manner. NaF (0.5 to 20 mM) increased cAMP levels by 1.5- to 3.-fold in both neutrophils and monocytes. Increases in cAMP levels were time-dependent; the maximal level was attained within 5 minutes after the addition of NaF, and cAMP levels remained elevated for up to 10 minutes. Only high concentrations of NaF (10 and 20 mM) increased both cAMP levels and O2- production. Therefore, a direct role of cAMP in O2- generation is not likely. It is speculated that since NaF (greater than 10 mM) can complex with extracellular Ca++, and thus reduce free Ca++ concentration required for O2- generation, a NaF-dependent increase in cAMP may restore cytosolic free Ca++ by mobilizing intracellular stores of Ca++. Further, in view of the proposed involvement of a phosphorylation-dephosphorylation mechanism in the regulation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, we speculate that NaF, by inhibiting phosphoprotein phosphatase activity, may indirectly activate the NADPH oxidase system and thus superoxide generation.

[Preliminary study on the nucleic acid hybridization technic in detecting HSV-2 DNA corresponding sequence of cancer tissues of the uterine cervix]

In this paper, 34 samples, 25 from 18 cervical carcinoma patients and 9 from 8 non-cervical carcinoma patients, were assayed using (alpha-32P) dCTP HSV-2 DNA probe and nucleic acid hybridization technic. It was shown that the positive rates of HSV-2 DNA corresponding sequence were 50% (2/4), 36% (5/14) and 12% (1/8) in the in situ cancer, invasive cancer and non-cervical cancer tissues. No HSV was isolated from 7 cancer specimens which showed a positive reaction by nucleic acid hybridization.

Localized conjunctival amyloidosis associated with extranodal lymphoma

A 62-year-old man was found to have a large asymptomatic amyloid nodule of the conjunctiva. Within the next year, a diffuse mixed small and large cell lymphoma of his scapula developed with amyloid in its stroma. No abnormal serum or urine protein was found. Subsequently, rib and paraspinal masses appeared. After irradiation and chemotherapy, the patient died of bronchopneumonia, 3 years after onset. By immunostaining, the amyloid of both conjunctiva and scapular tumor was of polyclonal immunoglobulin (AL) type, most prominently IgG and lambda chains, with lesser staining for IgA and kappa chains. The tumor cells showed a similar pattern. To our knowledge, this is the first report of systemic lymphoma and localized conjunctival amyloidosis without a serum paraprotein, and the first such association with a lymphoma of this cell type. Immunotyping of conjunctival amyloidosis should be performed to guide the workup for possible systemic disease.

Peanut agglutinin binding as a histochemical tool for diagnosis of eosinophilic granuloma

Histochemical detection of peanut agglutinin binding performed on tissue sections in 11 cases of eosinophilic granuloma of bone revealed simultaneous appearance of the reaction product both at the cell surface and within the cytoplasm (in the Golgi area) of a vast majority of Langerhans' cells. Based on this unique characteristic of Langerhans' cells, peanut agglutinin binding assay may represent a simple and inexpensive tool for morphologic differentiation of eosinophilic granuloma or other types of histiocytosis X from other monocytic and histiocytic lesions in equivocal cases.

The effect of ethanol on the production of lactate, triglycerides, phospholipids, and free fatty acids in the perfused human placenta

Eighteen fresh term placentas from normal deliveries were perfused to determine the biochemical response of the human placenta in the absence and presence of ethanol. The production rates were generally increased by ethanol administration; lactate, 22%; triglycerides, 49%; sphingomyelin, 362%; lecithin, 67%; lipid phosphorus, 780%; free fatty acids, 897%. Only the changes in lipid phosphorus and free fatty acids were significantly different (p less than 0.05). Glucose utilization rates were 600 and 551 mg per hour per placenta for eight control and 10 ethanol runs, respectively. The ethanol utilization rate was 442 mg per hour per placenta. Little difference in ultrastructural appearance between control and ethanol groups was observed at the level of ethanol administered. The general behavior of ethanol metabolism in human placenta seems qualitatively similar to that in the liver.