[Effect of dietary calcium on serum calcium and calmodulin activity of brain and hypothalamus in rats]

The effect of low calcium (LC) diet supplemented with various amount of calcium on serum calcium and calmodulin of rats was studied. The LC diet was mainly composed of corn low in calcium. The calcium content of LC diet was only half of that of the stock diet. Seventy Wistar rats were divided into 7 groups by weight and sex. Results showed that serum calcium in LC group was low and calmodulin activity was also low. These parameters were improved while calcium was supplemented in LC diet. There is a significant dose-response relationship among diet calcium, serum calcium and growth. When the total calcium in diet was increased up to 1000 mg/kg, serum calcium level was closed to that of normal and higher than the serum calcium in LC group significantly. The study demonstrated that low dietary calcium, hypocalcemia and low calmodulin are associated. When total dietary calcium was up to 1000 mg/kg, the growth retardation was attenuated.

[An experimental study on promoting reconstruction of microcirculation of the ischemic skin flap with basic fibroblast growth factor]

OBJECTIVE

This study was to determine whether the basic fibroblast growth factor (bFGF) could promote reconstruction of microcirculation in the ischemic portion of a random skin flap.

METHODS

Five methods were used in the experiment: measurement of the survival area of the skin flap; light and electron microscopic studies; immunohistochemical observation of the endothelial cell and microvessel image analysis technology (IAT).

RESULT

The survival area and microvessels in the skin flap were significantly increased in the treated group. The results indicate that bFGF can stimulate the proliferation and differentiation of endothelial cells in vivo and promote the microcirculation of the ischemic flap.

CONCLUSION

bFGF could promote reconstruction of microcirculation of the ischemic skin flap.

Dynamics of protein kinase CK2 association with nucleosomes in relation to transcriptional activity

Protein kinase CK2 has been implicated in control of cell growth and proliferation. Since growth stimuli evoke its preferential association with chromatin and nuclear matrix, we examined the dynamics of CK2 in nucleosomes fractionated on the basis of their transcriptional activity in the rat prostate. In this model, androgens induce expression of androgen-dependent genes but inhibit the androgen-repressed genes, whereas absence of androgens has the reverse effect. The level of CK2 was higher in the active than in inactive nucleosomes from normal prostate. Differential alterations in the levels of CK2 activity in the transcriptionally active versus inactive nucleosomes were evoked by androgen deprivation or administration. Comparison of the distribution of CK2 in active and inactive nucleosomes under varying androgenic conditions showed that the relative CK2 activity intrinsic to the transcriptionally active nucleosomes remained fairly stable, concordant with gene activity specific to the androgenic status. However, CK2 associated with inactive nucleosomes declined to a minimal level on androgen deprivation but increased rapidly on androgen administration (reflecting expression of multiple androgen-dependent genes). We suggest a role for CK2 in promoting the conformational transition of inactive nucleosomes to the active form and in the function of transcriptionally active nucleosomes.

[Polymorphism analysis of 4 loci of X-chromosome in a Chinese population of the Han nationality]

OBJECTIVE

To investigate the polymorphism of 4 loci of X-chromosome in the Hans.

METHODS

Using PCR-SSLP, the authors analysed the polymorphism of DXS1068, DXS7132, DXS6804 and DXS6799 in the X-chromosome in 70 randomly selected female Hans.

RESULTS

The number of alleles in the 4 loci were 5,5,5 and 6 respectively; there were no significant differences between the observed and estimated and genotype probabilities of the 4 loci; the estimates of heterozygosity of 4 loci were 0.6819, 0.6895, 0.7659 and 0.6483 respectively and there were no significant differences between the observed and estimated heterozygosity of the 4 loci.

CONCLUSION

The distribution of alleles and genotype probabilities of 4 loci all observe the Hardy-Weinberg equilibrium.

[Determination of adenosine and 3'-deoxyadenosine in Cordyceps militaris (L.) Link. by HPLC]

The establishment of a quantitative determination method by HPLC for adenosine and 3'-deoxyadenosine in Cordyceps militaris is reported. The sample was extracted with water under ultrasonic management for 2 hours. Chromatographic conditions: YWG C18 10 microns 5 mm x 200 mm; mobile phase consisted of NaH2PO4-NaOH buffer solution (pH 6.8); UV detection at 260 nm. The recoveries of adenosine and 3'-deoxyadenosine were 95.8% +/- 0.64% and 100.6% +/- 0.65% (n = 5) respectively.

[A study of genetic patterns of idiopathic epilepsy]

OBJECTIVE

To explore genetic patterns of idiopathic epilepsy (IEP).

METHODS

Using familial analysis, tests for multifactorial inheritance and segregation analysis, we studied 210 pedigrees with IEP found in a population survey in Shangdong province.

RESULTS

The genetic pattern of IEP is not polygenic but is mainly influenced by autosomal recessive disorders. The results of segregation analysis indicate that the genetic pattern of U*U multiplex families and U*A group is autosomal recessive. Only a few cases in U*U group may accept the assumption of autosomal recessive inheritance while the other are sporadic cases. The frequency of sporadic cases is approximately 78.5%. Genetic heterogeneity may influence U*U(f) group and U*U group.

CONCLUSION

Further and careful empirical scrutiny of U*U(f) group and the sporadic cases in U*U group offers the best hope for getting a clear understanding of genetic patterns and mechanisms in IEP.

Relationship between lung function and blood pressure in Chinese men and women of Beijing and Guangzhou. PRC-USA Cardiovascular and Cardiopulmonary Epidemiology Research Group

BACKGROUND

Previous studies of western populations have shown an inverse association between lung function and blood pressure.

METHODS

As part of a People's Republic of China-United States cardiopulmonary epidemiology study, we investigated the cross-sectional relationship between lung function and blood pressure in 6757 Chinese men and women, aged 35-54, from Beijing and Guangzhou, China. We also evaluated the longitudinal association between lung function and incident hypertension among 4818 initially normotensive subjects followed up between 2 and 4 years later.

RESULTS

In our cross-sectional analyses of baseline data, lung function varied inversely with baseline systolic (SBP) and diastolic blood pressure (DBP) in all women and in Beijing men. This association held for absolute and height-standardized forced vital capacity (FVC) and one-second forced expiratory volume (FEV1) (correlations: 0.10, -0.18, P < 0.0001), but was weaker after adjustment for age (correlations: -0.02, -0.11). The longitudinal follow-up showed that lower initial lung function levels were associated with a higher incidence of hypertension (SBP > or = 140 mmHg or DBP > or = 90 mmHg or currently using antihypertensive medications), but only among women in Guangzhou. Relative risks for hypertension incidence for those in the two lowest quintiles for FEV1 and FVC, compared to those in the two highest quintiles, ranged from 1.9 to 2.3 for Guangzhou women and from 0.9 to 1.4 for all other gender-city subgroups. Logistic regression analyses adjusting for age, baseline SBP, body mass index, smoking, education, and urban versus rural setting generally confirmed these patterns.

CONCLUSIONS

These results suggest a statistically significant, though weak, inverse relationship between lung function and blood pressure in Chinese men and women. This association is largely attributable to age and is present prospectively only in women.

Differential regulation of Pyk2 and focal adhesion kinase (FAK). The C-terminal domain of FAK confers response to cell adhesion

Pyk2 is a recently described cytoplasmic tyrosine kinase that is related to focal adhesion kinase (FAK) and can be activated by a variety of stimuli that elevate intracellular calcium. In this report, we showed that Pyk2 and FAK tyrosine phosphorylation are regulated differentially by integrin-mediated cell adhesion and soluble factors both in rat aortic smooth muscle cells, which express endogenous Pyk2 and FAK, and in transfected Chinese hamster ovary cells. We also found that Pyk2 is diffusely present throughout the cytoplasm, while FAK is localized in focal contacts as expected, suggesting that the different localization may account for their differential regulation. By analyzing a chimeric protein contain N-terminal and kinase domains of Pyk2 and C-terminal domain of FAK, we provided evidence that the distinctive C-terminal domains of Pyk2 and FAK were responsible for their differential regulation by integrins and soluble stimuli as well as their subcellular localization. Finally, we correlated FAK, Pyk2, and the chimeric protein binding to talin, but not paxillin, with their regulation by integrins and focal contact localization. These results demonstrate that the distinctive C-terminal domain of Pyk2 and FAK confer their differential regulation by different subcellular localization and association with the cytoskeletal protein talin.

Factors influencing survival rate in adenoid cystic carcinoma of the salivary glands

Ninety-one cases of adenoid cystic carcinoma (ACC) of the salivary glands with more than ten years' follow up were studied to investigate factors influencing the survival rate of patients, which vary according to site, histological type, clinical stage and nature of therapy. The data were statistically analysed for survival curves. Log rank tests were employed to assess the statistical significance of various groups. As a result, it may be concluded that tumour site, clinical stage and histological type are the important factors influencing the prognosis. ACC of the palate and parotid, early clinical stage, glandular/tubular histological type, and tumour without nerve involvement had the best prognosis. ACC in the submandibular gland, maxillary antrum and tongue, advanced clinical stage (stage III and IV), solid histological type, and tumour with nerve involvement had a poor prognosis.

[Cellular immunity in childhood iron deficiency anemia with recurrent respiratory infections]

OBJECTIVE

To examine interleukin-2 (IL-2) activity,serum soluble IL-2 receptor (sIL-2R) level and T lymphocyte subsets in peripheral blood from 63 childhood iron deficiency anemia (IDA) patients with recurrent respiratory infections(RRI).

METHODS

IL-2 activity, sIL-2R level and T lymphocyte subsets were assayed by MTT, ELISA and APAAP, respectively.

RESULTS

IL-2 activity, percentages of CD3+ and CD4+ cells as well as the ratio of CD4+/ CD8+ cells in the patients were significantly lower ( P < 0.01),while sIL-2R levels were higher than that in normal controls (P < 0.01). No significant change was found in the percentage of CD8+ cells.

CONCLUSION

Cellular immunity was impaired in childhood IDA with RRI.

A new nutritional assessment in patients with oral and maxillofacial malignancies

Combined subjective and objective nutritional assessment was performed on admission in 127 patients with oral and maxillofacial malignancies. On the basis of the nutritional assessment result, three typical nutritional parameters-body weight (BW) (X1), mid-upper-arm circumference (MAC) (X2), and hand grip strength (HGS) (X3) were used to establish a new nutritional assessment method that was developed by a computer-based discriminant analysis. The established model was as follows: Y1 = -126 + 1.09X1 + 1.34X2 + 0.23X3; Y2 = -95.63 + 0.96X1 + 1.17X2 + 0.19X3. In the model Y1 was regarded as good nutrition and Y2 as malnutrition. The larger value of Y stood for the patient's nutritional status (i.e. Y1 > Y2, well nourished; Y1 < Y2 malnourished). The new nutritional assessment correlates well with the combined subjective and objective nutritional assessment with a total agreement rate of 88.2%. With its simplicity and accuracy, the new nutritional assessment deserves a wide application in clinical situation.

[Epidemic trend of tuberculous meningitis in children of Heilongjiang province]

OBJECTIVE

To investigate the epidemic trend of tuberculous meningitis in children of Heilongjiang province in recent ten years, and to provide scientific evidence for control of the disease.

METHODS

The data, registered by 82 counties' antituberculosis institute, of tuberculous meningitis patients under 14 years were analyzed, and the epidemic trend of the disease was also discussed.

RESULTS

The incidence of tuberculous meningitis was 9.58 per 10,0000 populations in 1982, 2.17 per 10,0000 populations in 1992. The rate of annual decrease was 13.8%.

CONCLUSION

Participation of the government, improvement of pelple's life standard, control of sources of infection, and vaccination of BCG are effective measures for decreasing the incidence of this disease.

Responses of plasma fibronectin to the changes of dietary protein levels in rats

In this study, the plasma fibronectin was evaluated as a nutritional marker in protein- and protein-energy malnourished rats in comparison with plasma prealbumin, albumin, and total protein. The plasma fibronectin was determined by nephelometric assay based on the interaction of an antigen and antibody. The rats were subjected to three diets, containing 20, 5, and 0% casein, respectively, for 5 wk except in the last 2 wk, the rats on the 0% casein diet were re-fed on a 20% casein diet. The results showed that in the rats on a 5% casein diet (protein malnourished), the plasma fibronectin concentration rose significantly in the early stage and normalized thereafter. In the rats subjected to a 0% casein diet (protein-energy malnourished), the plasma fibronectin concentration did not decline quickly in response to protein depletion, compared with the plasma prealbumin, albumin, and total protein concentrations. Following the re-feeding of a 20% casein diet in the last 2 wk, the plasma fibronectin concentration was restored earlier than other plasma protein concentrations. No significant change in plasma fibronectin concentration was found in the rats receiving a 20% casein diet (control) over the 5 wk feeding period. It is concluded that plasma fibronectin may not be a suitable marker for protein or protein-energy malnutrition, though it is a sensitive index for nutritional rehabilitation.

[Production of anti-enteric adenovirus monoclonal antibody by electrofusion and semi-solid medium culture]

Ten million splenocytes from the enteric adenovirus (Ad40/41) immunized mice were fused with 3 x 10(6) myeloma cells by electrofusion. Then, the cells were selectively cultured in methyl cellulose semi-solid medium. Eighteen clones of hybridoma were directely picked out from the culture plates and 7 of them could secret high level specific antibodies to enteric adenovirus. So far, the anti-Ad40/41 virus monoclonal antibodies were successfully generated by the protocal of electrofusion accompanied with selective culture in methyl cellulose semi-solid medium.

Temporal difference learning applied to sequential detection

This paper proposes a novel neural-network method for sequential detection, We first examine the optimal parametric sequential probability ratio test (SPRT) and make a simple equivalent transformation of the SPRT that makes it suitable for neural-network architectures. We then discuss how neural networks can learn the SPRT decision functions from observation data and labels. Conventional supervised learning algorithms have difficulties handling the variable length observation sequences, but a reinforcement learning algorithm, the temporal difference (TD) learning algorithm works ideally in training the neural network. The entire neural network is composed of context units followed by a feedforward neural network. The context units are necessary to store dynamic information that is needed to make good decisions. For an appropriate neural-network architecture, trained with independent and identically distributed (iid) observations by the TD learning algorithm, we show that the neural-network sequential detector can closely approximate the optimal SPRT with similar performance. The neural-network sequential detector has the additional advantage that it is a nonparametric detector that does not require probability density functions. Simulations demonstrated on iid Gaussian data show that the neural network and the SPRT have similar performance.

Clinical observation on efficacy of electro-acupuncture therapy in hyperplasia of mammary glands and its effect on immunological function

Based on our work on electro-acupuncture therapy of hyperplasia of mammary glands and in order to observe further the relationship between immunological function and E2 in hyperplasia of mammary glands, we determined the change not only in immunological function before and after electro-acupuncture in 44 in-patients with hyperplasia of mammary glands and having the same menstruation date, but also in electro-acupuncture treated rat hyperplasia of mammary glands model. We found that there was decrease of immunological function in hyperplasia of mammary glands and this function could be remarkably enhanced by electro-acupuncture both in hyperplasia of mammary glands patients and in rat hyperplasia of mammary glands model. The mechanism implies it might be that the inhibitory effect on immunological function exerted by high concentration of E2 was lowered by electro-acupuncture, hence the immunological function was reinforced. The results of this study are important in exploration of both the pathogenesis of this disease and the mechanism of electro-acupuncture, and in reducing the incidence of breast carcinoma.

[Comparisons of three simple nutritional assessments applied to patients with oral and maxillofacial malignancies]

Combined subjective and objective nutritional assessment (SNA), concise nutritional assessment (CNA), general nutritional status score (GNS), and subjective global assessment of nutritional status (SGA) were applied to assess the nutritional status of 127 patients with oral and maxillofacial malignancies. On this base SNA was used as a standard nutritional assessment to compare the validities of CNA, GNS, and SGA. The results showed: 1) the total agreement rate of CNA (88.2%) was higher than that of GNS (78.0%) and SGA (78.7%); 2) the false positive rate (9.9%) and false negative rate (15.2%) of CNA was lower than that of GNS (17.3%, 30.4%) and SGA (14.8%, 32.6%); 3) the diagnosis index of CNA (74.9%) was significantly (P < 0.05) higher than that of GNS (52.3%) and SGA (52.6%); and 4) the nutritional parameters of CNA were measured by instruments with little man-made errors. These results indicate that CNA can be regarded as the best nutritional assessment for the patients in oral and maxillofacial surgery.

Kinship and familiarity as factors affecting social transfer of food preferences in adult Mongolian gerbils (Meriones unguiculatus)

Experiments were carried out with Mongolian gerbils (Meriones unguiculatus) to assess whether a socially mediated acquisition of diet selection exists in this species. Results showed that a gerbil was influenced in its diet choices by information extracted during a brief period of interaction with a familiar conspecific that had recently eaten a novel food. Data revealed that the acquisition of a food preference from a conspecific depends on the existence of a social bond between the interacting gerbils. Either genetic relatedness (being brother or sister raised in different litters) or familiarity (being bred in the same litter or being member of a reproductive pair) is necessary for the transfer of information. Unfamiliar and unrelated observer gerbils did not selectively choose their demonstrator's food.

Genomic organization of TEL: the human ETS-variant gene 6

We have constructed a detailed map of the genomic region containing the ETS-variant gene 6 (ETV6), involved in translocations and deletions associated with hematologic malignancies. Thirty-eight cosmids were characterized belonging to two contigs spanning 340 kb, and an EcoRl restriction map was developed. The gap between the two contigs, 2 kb in size, was closed by PCR. The contigs contain the complete coding sequence and the 5' and 3' UTRs of ETV6. Eight exons accounting for the ETV6 cDNA sequence were identified. The helix-loop-helix (HLH) motif is coded by exons 3 and 4, whereas exons 6-8 code for the ETS DNA-binding domain. All introns show consensus 5' donor and 3' acceptor splice sites. Introns 1 and 2 span 100 and 82 kb, respectively, and introns 3-7 range from 15 to 1.3 kb. An alternative exon 1 (exon 1B) is localized in intron 2. The 5' end of the ETV6 gene is associated with a CpG island characterized by the presence of four Notl, four Sacll, and three BssHll recognition sites and several SP1- and AP2-binding motifs. Alternative polyadenylation at the 3' end of the ETV6 gene generates the three transcripts of 6200, 4300, and 2400 nucleotides, respectively. The ETV6 gene spans 240 kb and is flanked at its 5' and 3' end by D12S1697 and D12S98, respectively. The markers D12S1095 and D12S89 are located in the first intron. Two new DNA polymorphisms were identified in the ETV6 gene, which will be useful for the analysis of loss of heterozygosity reported for the ETV6 gene in leukemia.

The 12;21 translocation involving TEL and deletion of the other TEL allele: two frequently associated alterations found in childhood acute lymphoblastic leukemia

A recurrent t(12;21)(p13;q22) has recently been described in human acute lymphoblastic leukemias (ALLs). This translocation fuses TEL and AML1, two genes previously cloned from translocation breakpoints in myeloid leukemias. In addition, allelic loss of the TEL gene can be detected in 15% to 22% of childhood ALLs. In the present study, we have sought allelic deletions of TEL and the presence of the t(12;21) in 50 children with B-lineage ALL, using a combination of microsatellite typing, fluorescent in situ hybridization (FISH), and analysis of the fusion transcripts resulting from the TEL-AML1 gene fusion. Our results indicate that the association between the t(12;21) and the deletion of the nontranslocated allele of TEL is among the most frequent abnormalities observed in B-lineage ALLs. FISH analysis using several cosmid probes showed that, in one patient with a t(12;21) translocation involving TEL, the second allele had an intragenic deletion. This observation points to TEL as the actual target of 12p12-13 deletions in patients that associate a t(12;21) with a deletion. The TEL-AML1 fusion RNA was found in all patients with the t(12;21) whereas the reciprocal AML1-TEL transcript was only found in a subset of patients, suggesting that only the protein product encoded by TEL-AML1 is likely to play a role in leukemogenesis. The observation that, in two patients with the t(12;21), a deletion of TEL was only present in a subclone indicates that this deletion was a secondary event that occurred after the translocation. The frequent occurrence of TEL deletions in patients with t(12;21) suggests that the deletion of the normal TEL allele subsequent to the t(12;21) provides a further proliferative advantage to leukemic cells.

Inverse Heat Transfer Analysis of Grinding, Part 2: Applications

Distributions of the heat flux to the workpiece and the convection heat transfer coefficient on the workpiece surface during straight surface grinding are estimated from measured temperatures in the workpiece subsurface using inverse heat transfer methods developed in Part 1. The results indicate that the heat flux to the workpiece is distributed approximately linearly (triangular heat source) along the grinding zone with about 70 to 75 percent of the total energy transported as heat to the workpiece for grinding of steels with a conventional aluminum oxide wheel and only about 20 percent with CBN superabrasive wheels. The wheel-workpiece contact length corresponding to the region of positive heat flux to the workpiece is found to be generally close to but slightly longer than the theoretical geometric contact length. The convection heat transfer coefficient for cooling by the applied grinding fluid is greatest just behind the trailing edge of the grinding zone where fluid is directly applied, and negligible ahead of the grinding zone.

Inverse Heat Transfer Analysis of Grinding, Part 1: Methods

Thermal analyses of the grinding process generally require assumptions concerning the distributions of the heat flux to the workpiece within the grinding zone and convective cooling outside the grinding zone. The present work is concerned with the use of inverse heat transfer methods to estimate the heat flux and convection heat transfer coefficient distributions on the workpiece surface during straight surface grinding from temperature measurements within the workpiece. In the present paper, three inverse heat transfer methods are developed: temperature matching, integral, and sequential methods. Each method is evaluated for accuracy and stability using simulated temperature data. The selection of the sampling frequency of the temperature measurements and location of the temperature sensor are found to be critical for both estimation accuracy and stability. In a second paper, these inverse heat transfer methods are applied to estimate the distributions of the heat flux and convection heat transfer coefficients on the workpiece surface for grinding of steels with aluminum oxide and CBN abrasive wheels.

Fluorescence resonance energy transfer reveals interleukin (IL)-1-dependent aggregation of IL-1 type I receptors that correlates with receptor activation

Fluorescence resonance energy transfer (FRET) was used to investigate whether interleukin-1 (IL-1) causes the aggregation of IL-1 type I receptors (IL-1 RI) at the cell surface. For these experiments, a noncompetitive anti-IL1 RI monoclonal antibody, M5, was labeled separately with a donor probe, fluorescein isothiocyanate, or with an acceptor carbocyanine probe, Cy3. Donor-labeled M5 and acceptor-labeled M5 were simultaneously bound to transfected mouse IL-1 RI on either C-127 mouse mammary carcinoma cells or on Chinese hamster ovary (CHO)-K1 cells, and the ratio of acceptor emission at 590 nm to donor emission at 525 nm (excitation at 488 and 514 nm) was monitored with flow cytometry as an indicator of FRET. Addition of a saturating concentration of human IL-1 alpha at 22 degrees C causes a time-dependent increase in FRET for both cell lines that indicates IL-1-dependent self-association of IL-1 RI. Binding of the IL-1 receptor antagonist at 22 degrees C causes little or no FRET for both cell lines, indicating a correlation between receptor aggregation and the ability of the ligand to stimulate a functional response. When donor-labeled and acceptor-labeled Fab fragments of M5 are used to monitor FRET, IL-1 alpha causes efficient energy transfer in the CHO-K1 cells at 22 degrees C, but not at 4 degrees C. In contrast, IL-1 alpha causes much less FRET at 22 degrees C in C-127 cells when the M5 Fab fragments are used instead of the intact bivalent M5. In a striking parallel, IL-1 alpha-dependent activation of prostaglandin E2 production depends on the bivalent M5 antibody in the C-127 cells, but is independent of this monoclonal antibody in the CHO-K1 cells. These results provide a strong correlation between the ability of IL-1 to cause the aggregation of IL-1 RI and the stimulation of a functional response.

Analysis of Transient Temperatures in Grinding

Temperatures generated in the workpiece during straight surface plunge grinding follow a transient behavior as the grinding wheel engages with and disengages from the workpiece, and throughout the entire grinding pass for workpieces which are shorter than needed to reach a quasi-steady state condition. In the present paper, a thermal model is developed for the transient temperature distribution under regular and creep-feed grinding conditions. Numerical results obtained using a finite difference method indicate that the workpiece temperature rises rapidly during initial wheel-workpiece engagement (cut in), subsequently reaches a quasi-steady state value if the workpiece is sufficiently long, and increases still further during final wheel-workpiece disengagement (cut out) as workpiece material is suddenly unavailable to dissipate heat. Cooling by a nozzle directed at the end face of the workpiece should significantly reduce the temperature rise during cut out.

Identification of a splice variant of the rat and human mineralocorticoid receptor genes

The sequence of a splice variant of the rat mineralocorticoid receptor (MR) gene is presented. A cDNA clone corresponding to rat MR was isolated from a rat brain cDNA library. Sequence analysis of the region corresponding to the DNA binding domain revealed the presence of a 12 base pair (bp) insertion. Analysis of mRNA from several rat tissues suggests that the variant is less abundant than the wild type in most tissues. The insertion variant is also a product of the human MR gene, the identical splice variant was also observed in human white blood cell mRNA. Unlike other splice variants reported for the MR, this variant alters the encoded protein by the addition of four amino acid residues in the DNA binding domain. The altered protein may influence the affinity of the MR for mineralocorticoid or glucocorticoid response elements.

Lack of association between HLA class II polymorphisms and essential hypertension in a Belgian population

The aim of the present study was to investigate whether the HLA class II polymorphisms contributes to the susceptibility to essential hypertension in the Belgian population. For this purpose we studied 120 hypertensive patients and 168 normotensive controls by means of a PCR-SSO assay. No significant difference in allele and genotype frequencies of the DRB and DPB1 loci could be found between the two groups. We concluded that essential hypertension as a multifactorial and heterogeneous disease cannot be associated with one of the HLA class II DRB and DPB1 alleles in Belgian patients.

[Comparison of toxic effects of brucite and aluminium-treated chrysotile on macrophage]

Toxicity of brucite and two kinds of chrysotile (Xinkang and Sichuan chrysotile) treated with aluminium chloride to alveolar macrophage from guinea pigs was compared in vitro. Results showed changes of toxicity, indicated as generation of O2-., increase in membrane lipid fluidity and leakage of intracellular potassium, etc., caused by aluminium-treated chrysotile, were significantly lower than those by bructite of same dose (P < 0.05 and P < 0.01, respectively), and changes of other toxic indicators, such as release of lactic dehydrogenase (LDH) and acid phosphatase (ACP) from macrophage and its mortality, were similar to those by brucite. It suggests aluminium chloride can be used to antagonize pathogenic bioactivity of chrysotile in practice.

TEL gene is involved in myelodysplastic syndromes with either the typical t(5;12)(q33;p13) translocation or its variant t(10;12)(q24;p13)

A t(5;12)(q33;p13) translocation is a recurrent chromosome abnormality in a subgroup of myeloid malignancies with features of both myeloproliferative disorders and myelodysplastic syndromes (MDSs). The molecular consequence of a t(5;12) is a fusion between the platelet-derived growth factor receptor-B gene on chromosome 5 and a novel ETS-like gene, TEL, on chromosome 12. We report on three patients with a t(5;12)(q33;p13) diagnosed as chronic myelomonocytic leukemia, and one case of a t(10;12)(q24;p13) in a progressive MDS, with eosinophilia and monocytosis. Involvement of the TEL gene in these chromosome translocations was investigated by fluorescence in situ hybridization (FISH) with cosmid probes containing selectively the 5' end or 3' end of TEL. Hybridization of these cosmids to the der(5)/der(10) or a der(12), respectively, demonstrated a rearrangement of TEL in both translocations, showing that the t(10;12) is a variant translocation of the t(5;12). Cloning of the fusion cDNA of one case of t(5;12) showed that the breakpoint occurred at the RNA level at exactly the same position as reported by Golub et al (Cell 77:307, 1994). In addition, the TEL gene on chromosome 12 could be localized between two probes previously mapped to 12p13, namely PRB1 and D12S178, leading to a better definition of the position of TEL in this chromosome region. Moreover, in the case involving chromosome 10, the breakpoint occurred between cKTN206 and cKTN312/LYT-10 at 10q24. Clinicohematological data in these studies as well as the restriction mapping of chromosomal breakpoints strongly suggest that (1) common features in MDSs involving the TEL gene are monocytosis and eosinophilia, (2) chromosomes other than no. 5 may be involved and at least a t(10;12)(q24;p13) variant chromosome translocation does exist in these MDSs, and (3) both standard and variant 12p/TEL translocations may be identified by FISH with appropriate probes.

Energy Partition to the Workpiece for Grinding with Aluminum Oxide and CBN Abrasive Wheels

An experimental investigation is reported of the energy partition to the workpiece for grinding of steels with aluminum oxide and cubic boron nitride (CBN) abrasive wheels. The energy input to the workpiece was obtained by measuring the temperature distribution in the workpiece using an embedded thermocouple technique and matching the results with analytically computed values. It was found that 60-75 percent of the grinding energy is transported to the workpiece as heat with an aluminum oxide abrasive wheel, as compared to only about 20 percent with CBN wheels. An analysis of the results indicates that the much lower energy partition to the workpiece with CBN can be attributed to its very high thermal conductivity whereby a significant portion of the grinding heat is transported to the abrasive instead of to the workpiece. The much lower energy partition to the workpiece with CBN wheels results in much lower grinding temperatures and a greatly reduced tendency for thermal damage to the workpiece.

Severe alport phenotype in a woman with two missense mutations in the same COL4A5 gene and preponderant inactivation of the X chromosome carrying the normal allele

The X-linked form of Alport disease, caused by mutations in the COL4A5 or the COL4A6 gene, usually leads to terminal renal failure in males, while affected females have a more variable and moderate phenotype. We detected in a female patient, with a severe Alport phenotype, two new missense mutations. One mutation (G289V) occurred in exon 15 and converted a glycine in a collagenous domain of COL4A5 to a valine. The second mutation, located in exon 46, substituted a cysteine proximal to the NC1 domain of COL4A5 for an arginine. In white blood cells and kidney both mutations were present on > 90% of the mRNA, while at the genomic level the patient was heterozygous for both mutations. The two mutations therefore occurred in the same COL4A5 allele. No mutation was found in the COL4A5 promoter region by sequencing nor was a major rearrangement of the normal allele detected. A skewed pattern of X inactivation was demonstrated in DNA isolated from the patient's kidney and white blood cells: > 90% of the X chromosomes with the normal COL4A5 allele was inactivated. It is suggested that this skewed inactivation pattern is responsible for the absence of detectable normal COL4A5 mRNA and hence the severe phenotype in this woman.

[Isolation and identification of enteric adenovirus in China]

Enteric adenovirus type 40/41 is considered to be the second major cause of gastroenteritis in young children. In this study fecal specimens 86-123 from diarrhea patients were isolated and examined in Grahm 293 cells. This induced cytopathic effect (CPE) at this cells. Viral particles were also found in fecal specimens and by electron microscopy. Examination of the isolate with Cambridge Biotech Adenoclone-Type 40/41 test kit indicated that it contained EAd. On the basis of the above studies, one strain of EAd was the first isolated virus in China.

Analysis of Energy Partition in Grinding

An analysis is presented for the fraction of the energy transported as heat to the workpiece during grinding. The abrasive grains and grinding fluid in the wheel pores are considered as a thermal composite which moves relative to the grinding zone at the wheel speed. The energy partition fraction to the workpiece is modeled by setting the temperature of the workpiece surface equal to that of the composite surface at every point along the grinding zone, which allows variation of the energy partition along the grinding zone. Analytical results indicate that the energy partition fraction to the workpiece is approximately constant along the grinding zone for regular down grinding, but varies greatly along the grinding zone for regular up grinding and both up and down creep-feed grinding. The resulting temperature distributions have important implications for selecting up versus down grinding especially for creep-feed operations.

A physical map of the region spanning the chromosome 12 translocation breakpoint in a mesothelioma with a t(X;12)(q22;p13)

We have constructed a physical map of a 4.6-cM region of human chromosome band 12p13.3 that contains a translocation breakpoint from a mesothelioma with a t(X;12)(q22;p13). The map contains a contig of 22 yeast artificial chromosomes (YACs), onto which we have placed 18 sequence tagged site (STS) markers, including seven genes: D12S370, FGF6, KCAN1, KCNA5, KCNA6, NTF3, and VWF. A second YAC contig, comprised of 22 YAC clones, was located distal to the mesothelioma breakpoint and contained 12 STS markers, including four genes (CACNL1A1, D12S380E, D12S381E, and D12S382E). Based on STS content and fluorescence in situ hybridization experiments, two stable, nonchimeric YAC clones were found that span the mesothelioma breakpoint. A long-range restriction map of an 800-kb region was constructed and used to refine the mesothelioma breakpoint to a region of approximately 100 kb, flanked by the potassium channel genes KCNA1 and KCNA5. The latter was confirmed by direct visual hybridization (DIRVISH) experiments, using cosmids isolated for markers flanking the breakpoint as probes.

Cloning and sequence of the Xenopus laevis homologue of the midkine cDNA

The Xenopus laevis (Xl) homologue of the midkine-encoding gene (MK) has been isolated and sequenced from a X. laevis cDNA library made from the head region of stage-22 embryo. The nucleotide and deduced amino-acid sequences show a high degree of conservation with the avian and mammalian MK and pleiotrophin (PTN) genes and gene products. Highly conserved domains may indicate important regions for the function of the MK and PTN proteins.

Lack of association between the I/D polymorphism of the angiotensin-converting enzyme gene and essential hypertension in a Belgian population

We tested the insertion/deletion (I/D) polymorphism of the ACE gene in 119 hypertensive patients and in 109 normotensive controls by means of the polymerase chain reaction (PCR). The allele and genotype frequencies of the I/D polymorphism in the ACE gene are essentially identical in both groups, regardless of age or sex. The I/D polymorphism of the ACE gene is thus not implicated in Belgian hypertensive patients.

Genetic study of indirect inguinal hernia

We performed a genetic analysis of 280 families with congenital indirect inguinal hernia ascertained in Shandong province. The multifactorial threshold model and segregation analysis were applied to these families to investigate the mode of inheritance of congenital indirect inguinal hernia. Our results indicate that congenital indirect inguinal hernia is not compatible with a multifactorial threshold model, and the frequent vertical transmission and high segregation ratio suggest autosomal dominant inheritance with incomplete penetrance and sex influence. Through further pedigree analysis of the multiple case families with at least two closely related affected members, we noted preferential paternal transmission of the disease gene, which might suggest the role of genomic imprinting in the aetiology of this condition.

Toxic effect of the bloom-forming Trichodesmium sp. (Cyanophyta) to the copepod Acartia tonsa

The toxicity of the marine cyanobacterium Trichodesmium sp. to the copepod Acartia tonsa was assessed in a series of experiments during a Trichodesmium bloom off the North Carolina coast in late October 1992. Healthy intact cells of Trichodesmium sp. were not toxic to A. tonsa and were ingested by A. tonsa when no other foods were available. However, homogenized Trichodesmium cells were toxic to A. tonsa, suggesting that Trichodesmium sp. contains certain type(s) of intracellular biotoxins. This hypothesis was consistent with the observed high mortality when A. tonsa was treated with aging Trichodesmium sp. cells or with filtered cell homogenate. The affected copepods showed weakness, recumbency, and reduced responsiveness. Many were observed to have distended intestines. Bioassays using aged Trichodesmium sp. cells and filtered homogenate demonstrated a dose-dependent effect on A. tonsa survival.

Differential splicing of COL4A5 mRNA in kidney and white blood cells: a complex mutation in the COL4A5 gene of an Alport patient deletes the NC1 domain

PCR conditions were optimized to amplify the COL4A5 cDNA from lymphoblasts and kidney tissue. Sequencing of the COL4A5 mRNA isolated from the kidney of an Alport syndrome patient revealed two differences with the published sequence. One divergence, the insertion of an 18 bp sequence between exon 11 and 10 of the COL4A5 mRNA added two Gly-X-Y triplets to the COL4A5 sequence and was subsequently found in the mRNA of four normal kidney mRNA samples. This sequence was absent in all white blood cell RNA samples sequenced by us, indicating tissue specific splicing with the presence of an additional exon in kidney COL4A5 mRNA. This finding of differential splicing of COL4A5 mRNA in kidney and white blood cells might affect the use of white blood cell mRNA for the analysis of Alport mutations. Second, a complex mutation was detected in the mRNA from the AS patient introducing a premature stop codon in the message, deleting part of the triple helical domain and the complete NC domain. The mother of the patient was shown to be heterozygous for this mutation.

Site-specific methylation inhibits transcriptional activity of platelet-derived growth factor A-chain promoter

Expression of the platelet-derived growth factor (PDGF) A-chain gene is temporally and spatially restricted in development and highly regulated in selected normal and tumor cell lines. Because DNA methylation appears to be important in regulating tissue specific gene expression, we tested the influence of in vitro methylation of the human PDGF A-chain promotor on its activity in vivo in transient transfection assays. We now report that PDGF A-chain promoter activity is strongly repressed by DNA methylation in a DNA sequence-specific manner and that the repression of promoter activity by methylation requires a methyl CpG-binding protein(s). We also report that incubation of HeLa cells with 5-azacytidine sharply increases levels of endogenous PDGF A-chain gene transcripts. These results indicate that the promoter activity of the PDGF A-chain gene is sharply and selectively reduced by in vitro DNA methylation and that DNA methylation in vivo also may reduce its function in selected cell lines.

Identification of a novel tyrosine kinase receptor-like molecule in neuroblastomas

Growth factor receptors are important determinants of both normal and abnormal cell growth. We have now used degenerate primers designed from conserved tyrosine kinase domains to identify and clone a novel receptor-like molecule (designated Nbtk-1) from a NB41 mouse neuroblastoma cell line. Nbtk-1 is related to the met proto-oncogene family of tyrosine kinase receptors. Transcripts of approximately 2.1 and 2.6 kb have been found in mouse cell lines and one transcript of approximately 3 kb in human cell lines and in a wide range of primary human tumors, such as neuroblastomas, primitive neuroectodermal tumors (PNETs), Wilms' tumors, and melanomas and in the corresponding normal human tissues. These observations suggest that Nbtk-1 may have important roles in normal and tumor cell growth.

Analysis of Fluid Flow through the Grinding Zone

A theoretical model of fluid flow in grinding has been developed by an analysis of fluid flow through a porous medium. Fluid tangential velocity, radial velocity, depth of penetration into the wheel, and the useful flow rate through the grinding zone are predicted by using this model. The analysis indicates that the nozzle position, nozzle velocity (or flow rate), and the effective wheel porosity are the three main factors which most significantly influence the useful flow rate through the grinding zone. A dimensionless effective wheel porosity parameter is introduced which is the ratio of the effective wheel porosity to its bulk porosity. By fitting the theoretical analysis to available experimental results, creep feed wheels were found to have much bigger dimensionless effective porosities than conventional wheels, which enhances their ability to more effectively pump fluid through the grinding zone.

Ambulatory blood pressure monitoring in elderly patients with isolated systolic hypertension

OBJECTIVES

This study compared clinic and ambulatory blood pressure measurement and the reproducibility of these measurements in older patients with isolated systolic hypertension (ISH).

PATIENTS

Eighty-seven patients aged greater than or equal to 60 years with ISH on clinic measurement were followed in the placebo run-in phase of the Syst-Eur trial.

METHODS

Clinic blood pressure was defined as the mean of two blood pressure readings on each of three clinic visits (six readings in total). Ambulatory blood pressure was measured over 24 h using non-invasive ambulatory blood pressure monitors.

RESULTS

Daytime ambulatory systolic pressure was, on average, 21 mmHg lower than the clinic blood pressure, whereas diastolic pressure was, on average, similar with both techniques of measurement. In the 42 patients who had repeat measurements, clinic blood pressure levels nad the amplitude of the diurnal blood pressure profile (fitted by Fourier analysis) were equally reproducible. However, both were less reproducible than ambulatory blood pressure levels. The repeatability coefficients, expressed as per cent of near maximum variation (four times the standard deviation of a given measurement), were 52% and 45% for the clinic systolic and diastolic pressures, 56% and 42% for the amplitude of the diurnal profile, and 29% and 26% for mean 24-h pressures.

CONCLUSIONS

In older patients with ISH, clinic and ambulatory systolic blood pressure measurements may differ largely: the prognostic significance of this difference remains to be elucidated. Furthermore, in these patients the level of pressure is more reproducible by daytime ambulatory blood pressure measurement than by clinic measurement.

[Pharmacological study on Cordyceps sinensis (Berk.) Sacc. and ze-e Cordyceps]

The Ze-e Cordyceps is similar to the Cordyceps sinensis in such pharmacological actions as calming, enduring hypoxia, dilating trachea, male sex hormone action, antiphlogistic and toxicity, etc. It is thus suggested that the Ze-e Cordyceps may be used place of the Cordyceps sinensis in clinical practice.