Plastic bending of sapphire fibers for infrared sensing and power-delivery applications

Sapphire fibers with diameters of 325-850 microm were plastically bent by CO(2) laser beams with typical bending radii as small as 2.8 mm. The additional optical loss caused by a single bend was less than 0.1 dB (at 900 nm), the damage threshold of the bent fibers was higher than 150 MW/cm(2) for Nd:YAG laser pulses, and the high mechanical strength of the bending area was also proved. Several successful applications of bent sapphire fibers have shown that plastically bent sapphire fibers are promising for use in IR sensing and power-delivery applications.

[Amplification, cloning and expression of a gene encoding hexose transporter of Plasmodium falciparum]

OBJECTIVE

To amplify, clone and express of a gene encoding hexose transporter of Plasmodium falcipuram (PfHT1) from Southern China isolate FCC1/HN for studing the immune of recombinant which protective from malaria parasite infection.

METHODS

Cultivation of P. falciparum isolate FCC1/HN in vitro; extraction of genomic DNA from FCC1/HN using the alkali specific cleavage method; PCR amplification of PfHT1 and cloning into eukaryotic expression vector, pEGFPN3. The recombinant as introduced into mammalian cells, HEPG2 by using liposome-mediated transfection.

RESULTS

The gene encoding PfHT1 was specifically amplified from the genomic DNA of P. falciparum isolate FCC1/HN. The size of amplified fragment was 1,516 base pair. The eukaryotic expression recombinant, pN3-HT1, was constructed and expressed steadily in the hepatocarcinoma cell lines, HEPG2.

CONCLUSION

The gene encoding PfHT1 was successfully amplified and cloned. The pN3-HT1/HEPG2 cell line was built for expressing fusion protein of GFP-HT1.

[Study on the volatile oil of Nardostachys chinensis]

The volatile oil of Nardostachys chinensis Batal has been studied by GC-MS, and 21 compounds have been isolated and identified. The total content of the components are 88.51%. Major compounds have been identified as Calarene (29.44%). delta 1(10)-Aristolenone-2 (16.57%) and Jatamansinol (8.80%).

[Detection of telomerase activity in prostate needle-biopsy samples]

OBJECTIVE

To detect telomerase activity inprostate needle-biopsy samples and its role in diagnosis and prognosis of prostate cancer.

METHODS

20 tissue samples of prostate cancer tissues and 16 samples of adjacent tissues were obtained by needle-biopsy guided by transrectal B ultrasonography. 16 samples of benign prostatic hyperplasia tissues were obtained by prostatectomy and were confirmed pathologically. Telomerase activity was revealed by modified PCR-based telomeric repeat amplication protocol (TRAP)-silver staining assay.

RESULTS

Telomerase activity was revealed in 18 cases of prostate cancer. In tissues adjacent to prostate cancer, telomerase activity was found in 7 of 11 cases of prostatic intraepithelial neoplasia (PIN), and in 2 of 5 cases of BPH. None of tissue samples from patients with BPH showed telomerase activity.

CONCLUSIONS

Telomerase activity in prostate needle-biopsy samples might be an useful marker for detecting prostate cancer and biological malignancy.

Expression of heat shock protein 90 beta in human gastric cancer tissue and SGC7901/VCR of MDR-type gastric cancer cell line

OBJECTIVE

To examine the expression of heat shock protein (HSP) 90 beta in human gastric cancer tissue and SGC7901/VCR of MDR-type gastric cancer cell line.

METHODS

Immunohistochemical staining and in situ hybridization methods.

RESULTS

Heat shock protein 90 beta was mainly located in the cell cytoplasma and weakly expressed in non-cancerous gastric mucosa. The expression rates of HSP90 beta in normal gastric mucosa, gastritis and paracancer tissues were 11.76%, 13.04% and 11.42% respectively, and there were no significant differences between them (P > 0.05). The expression of HSP90 beta was increased in gastric cancer. The positive rate of HSP90 beta in gastric cancer tissue was 30.00%, and was higher than non-cancerous gastric mucosa (P < 0.05). The expression rates of HSP90 beta in well differentiated, moderately differentiated, poorly differentiated gastric cancer and mucinous carcinoma were 15.38%, 31.25%, 33.33%, and 42.85% respectively. The expression of HSP90 beta in SGC7901/VCR of MDR-type gastric cell line was higher than in its parental cell line SGC7901. In situ hybridization showed that the positive signal of HSP90 beta was mainly located in the cell cytoplasma.

CONCLUSIONS

The expression of HSP90 beta was higher in gastric cancer tissue than in non-cancerous gastric mucosa. In gastric cancer tissue, the expression of HSP90 beta was greater in poorly differentiated cancer tissue, and in SGC7901/VCR of MDR-type gastric cancer cell line the expression of HSP90 beta was higher than that in its parental cell line SGC7901.

Standard growth curve chart for body height of Chinese adolescent for orthodontic diagnosis

OBJECTIVE

To make a standard growth curve chart on the body height of Chinese adolescents.

METHODS

Statistical data from 32,524 Sichuan students aged 7 to 19 years were surveyed in 1995. Mean values of the annual increment of body height and the ages of the pubertal growth periods were analyzed.

RESULTS

During the period between 9 and 13 years of age, females grow faster than their male peers. After age 13 years, males surpass females, and the difference in physical growth and development becomes more pronounced.

CONCLUSIONS

The new standard growth curve chart on the body height of Chinese adolescent may be applied to better understand the growth pattern of Chinese orthodontic patients.

Suppressive action produced by beta-amyloid peptide fragment 31-35 on long-term potentiation in rat hippocampus is N-methyl-D-aspartate receptor-independent: it's offset by (-)huperzine A

Extracellular recordings of field potential from CA1 region of rat hippocampal slices were used to observe the effects of a shorter synthetic fragment of beta-amyloid peptide (A beta31-35) on the induction of long-term potentiation (LTP) and the action of (-)huperzine A, a potent acetylcholinesterase (AChE) inhibitor on these processes was also observed. The results showed that: (1) 0.1 microM A beta31-35 suppressed the induction of LTP in a similar mode as the longer fragment A beta25-35, did, while they did not change the amplitude of the baseline population spike (PS); (2) when PSs were recorded separately in Mg2+-free medium, which unveils the N-methyl-D-aspartate (NMDA)-mediated responses, both A beta31-35 and A beta25-35 showed little effect on the components of multiple PSs; (3) two concentrations of 0.1 microM or 1.0 microM (-)huperzine A showed no effects on the PS amplitude while the latter could enhance the LTP and (4) co-administration of (-)huperzine A with 0.1 microM concentration could block most of the suppressive action induced by A beta31-35 or A beta25-35 upon the LTP. The results suggest that the shorter fragment A beta31-35, is long enough to suppress the induction of LTP and these two fragments might suppress the induction of LTP through a NMDA receptor-independent pathway that involves cholinergic terminals in hippocampus.

Purinoceptor-coupled Cl- channels in mouse heart: a novel, alternative pathway for CFTR regulation

1. P2-purinoceptors couple extracellular ATP to the activation of a Cl- current (ICl,ATP) in heart. We studied the molecular mechanism and intracellular signalling pathways of ICl,ATP activation in mouse heart. 2. Extracellular adenosine-5'-O-(3-thiotriphosphate) (ATPgammaS; 100 microM) activated ICl,ATP in both atrial and ventricular myocytes. A specific PKC inhibitor, bisindolylmaleimide blocked the effect of ATPgammaS while a PKC activator, phorbol 12, 13-dibutyrate (PDBu) activated a current with identical properties to ICl,ATP. Maximal activation of ICl,ATP by ATPgammaS or PDBu occluded further modulation by the other agonist, suggesting that they may activate the same population of Cl- channels. 3. Isoprenaline increased ICl,ATP pre-activated by ATPgammaS or PDBu, while isoprenaline or forskolin alone failed to activate any Cl- current in these myocytes. Adenosine 3',5'-cyclic monophosphothionate, a PKA inhibitor, prevented ATPgammaS or PDBu activation of ICl,ATP. Thus, ICl,ATP is regulated by dual intracellular phosphorylation pathways involving both PKA and PKC in a synergistic manner similar to cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channels. 4. Glibenclamide (50 microM) significantly blocked ICl,ATP activated by ATPgammaS or by the CFTR channel activator, levamisole. 5. The slope conductance of the unitary ICl,ATP in cell-attached patches was 11.8 +/- 0.3 pS, resembling the known properties of CFTR Cl- channels in cardiac myocytes. 6. The reverse transcription polymerase chain reaction and Northern blot analysis revealed CFTR mRNA expression in mouse heart. 7. We conclude that ICl,ATP in mouse heart is due to activation of CFTR Cl- channels through a novel intracellular signalling pathway involving purinergic activation of PKC and PKA.

Use of molecularly imprinted polymers in a biotransformation process

Molecularly imprinted polymers are highly stable and can be sterilised, making them ideal for use in biotransformation process. In this communication, we describe a novel application of molecularly imprinted polymers in an enzymatic reaction. The enzymatic condensation of Z-L-aspartic acid with L-phenylalanine methyl ester to give Z-L-Asp-L-Phe-OMe (Z-aspartame) was chosen as a model system to evaluate the applicability of using molecularly imprinted polymers to facilitate product formation. When the product-imprinted polymer is present, a considerable increase (40%) in product yield is obtained. Besides their use to enhance product yields, as demonstrated here, we suggest that imprinted polymers may also find use in the continuous removal of toxic compounds during biochemical reactions.

[Detection of stable expression of human interlukin-2 gene in transfected keratinocytes]

OBJECTIVE

To investigate the stable expression and secretion of human interlukin-2 gene in transfected keratinocytes.

METHODS

Keratinocytes were transfected with lipofectamine and selected by G418. Then the samples were analyzed with the techniques of DNA dot blot, RNA dot blot, hybridization in situ, immunohistochemistry, Western blot and MTT.

RESULTS

The positive signals were observed in transfected keratinocytes by DNA dot blot, RNA dot blot, hybridization in situ and immunohistochemistry. With Western blot analysis, a specific band exhibiting a molecular weight of 15,000 was detected in transfected keratinocytes, which was in acordance with that of IL-2. The expression of IL-2 can maintain for up to 1 month. The amounts of IL-2 in the supernatants of two and four passages transfected keratinocytes were 27.7 U/ml and 15.0 U/ml, respectively.

CONCLUSION

Keratinocytes have the potential for stable gene expression and secretion of active transgene products. Thus, it is possible to use keratinocytes as a target cell for gene transfection, gene expression and even gene therapy.

[Studies on standard growth curve chart on body weight of adolescent Chinese for orthodontic diagnosis]

OBJECTIVE

To establish the first new annual increase and growth curve charts on the body weight of Chinese children.

METHODS

Data were surveyed in 1995, which were obtained from subjects consisting of 32524 students aged from 7 to 19 years in Sichuan province.

RESULTS

Mean values of the annual increment of body weight, sex and area difference were analyzed.

CONCLUSION

The new standard growth curve chart on the body weight is very useful for orthodontic diagnosis, treatment and prognosis.

Growth and glucose repression are controlled by glucose transport in Saccharomyces cerevisiae cells containing only one glucose transporter

A set of Saccharomyces cerevisiae strains with variable expression of only the high-affinity Hxt7 glucose transporter was constructed by partial deletion of the HXT7 promoter in vitro and integration of the gene at various copy numbers into the genome of an hxt1-7 gal2 deletion strain. The glucose transport capacity increased in strains with higher levels of HXT7 expression. The consequences for various physiological properties of varying the glucose transport capacity were examined. The control coefficient of glucose transport with respect to growth rate was 0.54. At high extracellular glucose concentrations, both invertase activity and the rate of oxidative glucose metabolism increased manyfold with decreasing glucose transport capacity, which is indicative of release from glucose repression. These results suggest that the intracellular glucose concentration produces the signal for glucose repression.

Frequency of the fragile X syndrome in Chinese mentally retarded populations is similar to that in Caucasians

Fragile X syndrome is recognized as the most common inherited cause of mental retardation in western countries. The prevalence of the fragile X syndrome in Asian populations is uncertain. We report a multi-institutional collaborative study of molecular screening for the fragile X syndrome from 1,127 Chinese mentally retarded (MR) individuals. We found that 2.8% of the Chinese MR population screened by DNA analysis had the fragile X full mutation. Our screening indicated that the fragile X syndrome prevalence was very close to that of Caucasian subjects. In addition, we found that 62.5% of fragile X chromosomes had a single haplotype for DXS548-FRAXAC1 (21-18 repeats) which was present in only 9.7% of controls. This unique distribution of microsatellite markers flanking the FMR1 CGG repeats suggests that the fragile X syndrome in Chinese populations, as in the Caucasian, may also be derived from founder chromosomes.

[Studies on standard growth curve chart on body height of Chinese adolescent for orthodontic diagnosis]

OBJECTIVE

To make a standard growth curve chart on the body height of Chinese adolescent.

METHODS

Statistical data were surveyed in 1995, which were obtained from subjects consisting of 32,524 students aged from seven to nineteen years in the province of Sichuan.

RESULTS

Mean values of the annual increment of body height and the ages of the pubertal growth periods were analyzed.

CONCLUSION

The new standard growth curve chart on the body height of adolescent chinese were applied for better understanding the growth pattern of chinese orthodontic patients.

Characterization of three distinct cDNA clones encoding cysteine proteinases from maize (Zea mays L.) callus

In previous work, a 33 kDa cysteine proteinase was found in callus initiated from maize (Zea mays L.) resistant to fall armyworm feeding. A callus cDNA library from the maize inbred Mp708 was screened with oligonucleotides derived from the N-terminal amino acid sequence of the 33 kDa proteinase and several cDNA clones were isolated and sequenced. A cDNA clone encoding the 33 kDa cysteine proteinase, mir1, was identified. Two additional clones, mir2 and mir3, encoding putative cysteine proteinases were also identified. mir2 and mir3 are distinct from mir1 and each other, but show a high degree of homology. All of the mir cDNA clones map to distinct sites on the maize genome. Amino acid sequences encoded by the mir clones are similar to other known cysteine proteinases and are most closely related to the oryzain-alpha and -beta precursors. The ERFNIN motif and a 12 amino acid conserved sequence are present in the propeptide region of the putative proteinases encoded by mir clones. mir2 and mir3 appear to have C-terminal extensions. The phylogenetic tree of nucleotide sequences of mir1, mir2, mir3 and other representative cysteine proteinases from protozoa, plants and animals was constructed.

Functional expression, quantification and cellular localization of the Hxt2 hexose transporter of Saccharomyces cerevisiae tagged with the green fluorescent protein

The Hxt2 glucose transport protein of Saccharomyces cerevisiae was genetically fused at its C-terminus with the green fluorescent protein (GFP). The Hxt2-GFP fusion protein is a functional hexose transporter: it restored growth on glucose to a strain bearing null mutations in the hexose transporter genes GAL2 and HXT1 to HXT7. Furthermore, its glucose transport activity in this null strain was not markedly different from that of the wild-type Hxt2 protein. We calculated from the fluorescence level and transport kinetics that induced cells had 1.4x10(5) Hxt2-GFP molecules per cell, and that the catalytic-centre activity of the Hxt2-GFP molecule in vivo is 53 s-1 at 30 degrees C. Expression of Hxt2-GFP was induced by growth at low concentrations of glucose. Under inducing conditions the Hxt2-GFP fluorescence was localized to the plasma membrane. In a strain impaired in the fusion of secretory vesicles with the plasma membrane, the fluorescence accumulated in the cytoplasm. When induced cells were treated with high concentrations of glucose, the fluorescence was redistributed to the vacuole within 4 h. When endocytosis was genetically blocked, the fluorescence remained in the plasma membrane after treatment with high concentrations of glucose.

First trial of home ECG and blood pressure telemonitoring system in Macau

OBJECTIVE

To determine the feasibility of home monitoring of patients with cardiac disease or hypertension.

METHODS

An improved home electrocardiographic and blood pressure telemonitoring system linked to a central workstation was tested in 10 patients in Macau for 3 months.

RESULTS

The total number of connections was 1377. Of the automatic alarm connections, 32.5% were false positive, with the percentage of false positives ranging from 7.6 to 54.6 for different patients. Both patients and physicians found the system easy to use.

CONCLUSIONS

Further investigation is required to match the number of patients with the system capacity. A more robust dysrhythmia detection algorithm is needed to reduce the number of false alarms. Nevertheless, the results were sufficiently good that the trial is being expanded.

5-HTTLPR variants not associated with autistic spectrum disorders

To determine whether there is an association of polymorphic variants of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) and autistic spectrum disorders, we analyzed the 5-HTTLPR genotypes of 72 autistic subjects, 11 fragile X syndrome patients with autistic behavior, 43 normal subjects, and 49 fragile X syndrome non-autistic subjects. The distribution frequency of 5-HTTLPR long allele (L) and the short allele (S) variants showed no differences between subjects. Our findings do not support the hypothesis that polymorphic 5-HTTLPR variants are a susceptibility factor for autistic disorders.

Sapphire-fiber thermometer ranging from 20 to 1800 degrees C

A novel, to our knowledge, sapphire-fiber thermometer ranging from 20 degrees to 1800 degrees C is presented that combines the radiance detection and the fluorescent lifetime detection schemes into one system. The thermal probe is a sapphire fiber grown from the laser-heated pedestal growth method. Its end part is doped with Cr(3+) ion and coated with some radiance material to constitute a minifiber cavity. The sapphire fiber is coupled with a Y-shaped silica fiber bundle for signal transmission. Radiance and fluorescence signal processing schemes are also set up within one thermometer system. A sandwich two-band p-i-n detector is used that may respond to both the radiation and the fluorescence. Preliminary experimental results show that the thermometer is suitable for practical application with potential long-term stability and a high-temperature resolution.

Effects of acupuncture on the levels of endothelin, TXB2, and 6-keto-PGF1 alpha in apoplexy patients

In order to delve into the mechanism governing the treatment of apoplexy by acupuncture at yangming channel points as main points, we observed the changes in the endothelin (ET) level in plasma, TXB2 and 6-Keto-PGF1 alpha levels in urine in convalescent apoplexy patients during acupuncture treatment. The results showed that the ET level in plasma in convalescent apoplexy patients was significantly higher than that in healthy subjects (P < 0.05), and the ET level in plasma in patients was decreased after one course of acupuncture treatment. It was found that before treatment the TXB2 level in urine in apoplexy patients was significantly higher than in healthy subjects, and the 6-Keto-PGF1 alpha level in urine in the patients was significantly lower than that in healthy subjects, with an increased ratio of TXB2 to 6-Keto-PGF1 alpha. After acupuncture treatment, the TXB2 level in urine was lowered with a decrease in the ratio of TXB2 to 6-Keto-PGF1 alpha. All this indicated that one of the mechanisms governing acupuncture treatment of apoplexy acupuncture at yangming channel points as main points was that acupuncture could produce therapeutic effects by adjusting the imbalance of important vaso-active substances, ET, TXA2, and PGI2.

[Nonpalpable testicular masses incidentally discovered by ultrasound]

OBJECTIVE

To determine the diagnosis and management of impalpable testicular masses detected sonographically.

METHODS

We analyzed retrospectively the sonographic findings and pathologic results of such cases and reviewed related literature.

RESULTS

In over 600 patients receiving scrotal ultrasound, 14 aged on average 42.4 years (14 to 71 years) had 16 impalpable testicular masses, with a diameter of 5 to 30 mm (mean 12.1 mm). All masses were predominantly hypoechoic except for one appeared hyperechoic and calcified. Pathological examination showed 2 seminomas, 2 lymphomas, 2 testicular tuberculoses and cysts respectively. The other six were embryonal cell carcinoma, metastatic adenocarcinoma, testicular fibrosis, partial infarction, testis abscess, and hematoma. Malignant lesions accounted for 42.86% (6/14). In 13 of 14 patients, the affected testis was resected, while in 1 the testis spared for frozen sectioning revealed a benign cystic lesion.

CONCLUSIONS

Ultrasound findings can not differentiate malignant from benign in the impalpable lesions, and clinical history should be considered. All patients with indefinite diagnosis should undergo inguinal exploration and the testis can be spared if intraoperative frozen section diagnosis is negative. Ultrasound follow-up should be used only if there is a strong evidence of infection or trauma.

[New ellagic glycosides and known triterpenoids from Duchesnea indica Focke]

Two new ellagic glycosides, named ducheside A and ducheside B, have been isolated from Ducheside indica Focke. Their structures were established as 3'-O-methyl-ellagic acid-4-O-beta-D-xylopyranoside (I), 3'-O-methyl-ellagic acid-4-O-alpha-L-arabinofuranoside (II), respectively, on the basis of chemical method and spectral analysis. In addition, four known compounds were isolated and identified as 3 beta-hydroxylurs-12-en-28-oic acid (III), 2 alpha, 3 beta, 19 alpha-trihydroxylurs-12-en-28-oic acid (IV), 2 alpha, 3 beta, 19 alpha-trihydroxylurs-12-en-28-oic acid 28-O-beta-D-glucopyranoside (V), 2 alpha, 3 alpha, 19 alpha-trihydroxylurs-12-en-28-oic acid 28-O-beta-D-glucopyranoside (VI). Compounds IV, V, VI were isolated for the first time from Duchesnea genus.

Mitotic index and Alzheimer's disease

Alzheimer's disease (AD), a progressive neurodegenerative disorder, is diagnosed definitively by increased numbers of beta-amyloid plaques and neurofibrillary tangles in brain biopsy or autopsy specimens. There are no simple straightforward laboratory tests currently available for clinical diagnosis. We have found consistent reduction in mitotic index levels in skin fibroblast cultures from AD individuals compared with age- and sex-matched controls. These differences were enhanced by overnight exposure to colcemid (p = 0.04). Results suggest that mitotic index in skin fibroblasts cultures should be further investigated as a potential diagnostic indicator for AD.

Transcriptional activation by the Werner syndrome gene product in yeast

Werner syndrome (WS) is characterized by the premature occurrence of many age-related features. Before the cloning of the gene for WS (WRN), several reports suggested that transcriptional defects of genes may relate to the mechanisms of the occurrence of WS and natural aging. Because WRN, which encodes a helicase (WRN-H), has been cloned, we are attempting to clarify the mechanism of the transcriptional abnormalities found in WS cells, using WRN and WRN-H. In this article, we studied transcriptional activation of a promoter by WRN-H in a yeast assay system as a first step. The results showed that WRN-H functions as a transcriptional activator in the system. Furthermore, we performed additional transcriptional assays using various parts of WRN to define the critical region of WRN-H for transcriptional activation in yeast. The results revealed the critical region for the activation most likely mapped to the region of 315 to 403 aa. The region of 404 to 1309 aa may also effect activation in the presence of the critical region. The two regions contain an acidic domain, and the region of 404 to 1309 aa also contains a helicase domain. If this transcriptional activation by WRN-H occurs also in human cells in vivo, direct activation of the promoters by WRN-H could explain the results of somatic cell hybrid studies as well as the overexpressed genes detected in WS cells. However, our results should be interpreted with caution, because thus far, the transcriptional activation by WRN-H were only demonstrated using one promoter in a yeast system.

Competitive immunoassay for cyclosporine using capillary electrophoresis with laser induced fluorescence polarization detection

Frequent monitoring of immunosuppressive drug cyclosporine A (CsA) in blood samples of tissue transplant patients is required in clinical practice because of the narrow therapeutic range between the immunosuppressive effect and the toxic effect of this drug. We describe a competitive immunoassay capillary electrophoresis (CE) with laser induced fluorescence polarization detection method, which is rapid and sensitive for the determination of CsA. The method is based on the competitive immunochemical reaction between the analyte and fluorescent hapten (CsA*) with the antibody, CE separation of the antibody bound and free fluorescent CsA*, followed by the laser induced fluorescence polarization detection (LIFP) of the fluorescent species. The method detection limit is governed by the stability of the antibody-CsA* complex rather than by the detector noise. The use of post-column sheath flow cuvette LIFP detection resulted in excellent detection limit, typically 0.9 nM (or 9.10(-19) mol for 1 nl injection) of CsA. CsA in whole blood samples from organ transplant patients were measured and results agreed well with those obtained by using a standard fluorescence polarization immunoassay. Each determination took less than 3 min. The CsA metabolites AM9 and AM19 were also determined by using this technique, and their cross-reactivities with the antibody were 13% and 2%, respectively.

Molecular and epidemiological studies of Werner syndrome in the Japanese population

Werner syndrome (WS) is an autosomal recessive genetic disease characterized by many age-related features. The gene responsible for WS (WRN) has been isolated and contains a helicase domain, but its function is unknown. Six different mutations throughout the WRN gene have been reported in the Japanese population. We have studied whether patients with a specific mutation exhibit distinct phenotypes from others. Fourteen patients with different mutations showed almost the same signs and symptoms and, therefore, the C terminal part of the product appears to be crucial for its functions, although other parts may be important as well. Haplotype analyses using 13 microsatellites covering the 2.8-3.0 cM WRN region showed that two out of six different mutations had founder chromosomes. These two founder chromosomes may be evenly distributed throughout the western part of Japan, suggesting that these mutations go back to a time earlier than 1400 years ago.

Growth factor and cytokine-regulated hyaluronan-binding protein TSG-6 is localized to the injury-induced rat neointima and confers enhanced growth in vascular smooth muscle cells

Hyaluronan (HA) and HA-binding proteins have been implicated in a diverse array of biological processes, including development, tissue repair, and tumor invasion. However, the role of HA and HA-binding proteins in atherosclerosis and restenosis is poorly understood. PS4 (TSG-6) is a HA-binding protein expressed by cultured vascular smooth muscle cells (SMCs) in response to serum and growth factor stimulation. To delineate a possible role for TSG-6 in vascular disease progression, we have characterized its expression in cultured SMCs and in a rat vascular injury model, and we have studied the effect of constitutive overexpression of TSG-6 on SMC behavior. We found that interleukin-1 (IL-1) but not tumor necrosis factor or interleukin-6 was able to stimulate TSG-6 expression in SMCs. The IL-1 pathway could be distinguished from the growth factor pathway by its insensitivity to protein synthesis inhibitors. Furthermore, epidermal growth factor, fibroblast growth factor-1, and transforming growth factor-beta1 were all capable of augmenting maximum IL-1-induced expression of TSG-6. To gain further insight into the function of TSG-6 in SMCs, we examined the effect of constitutive overexpression of TSG-6 on these cells. We found that TSG-6-overexpressing cells grew >50% faster than control cells. Furthermore, this growth advantage became more evident in the absence of serum growth factors, with an average increase in cell number of 118% over control cells after 6 days. Consistent with these in vitro data, we observed intense immunostaining for TSG-6 in proliferating SMCs in the rat neointima after injury, whereas only an occasional cell was positive for TSG-6 in the medial layer and in nonballooned arteries. We conclude that the expression of TSG-6 is tightly controlled by growth factors and cytokines via two distinct pathways in SMCs and that overexpression of TSG-6 confers a growth advantage to these cells.

BRCA1 is a component of the RNA polymerase II holoenzyme

The familial breast-ovarian tumor suppressor gene product BRCA1 was found to be a component of the RNA polymerase II holoenzyme by several criteria. BRCA1 was found to copurify with the holoenzyme over multiple chromatographic steps. Other tested transcription activators that could potentially contact the holoenzyme were not stably associated with the holoenzyme as determined by copurification. Antibody specific for the holoenzyme component hSRB7 specifically purifies BRCA1. Immunopurification of BRCA1 complexes also specifically purifies transcriptionally active RNA polymerase II and transcription factors TFIIF, TFIIE, and TFIIH. Moreover, a BRCA1 domain, which is deleted in about 90% of clinically relevant mutations, participates in binding to the holoenzyme complex in cells. These data are consistent with recent data identifying transcription activation domains in the BRCA1 protein and link the BRCA1 tumor suppressor protein with the transcription process as a holoenzyme-bound protein.

Serum inhibits tight junction formation in cultured pigment epithelial cells

PURPOSE

These experiments were designed to characterize tight junction formation by retinal pigment epithelial (RPE) cells in vitro and to compare the effects on this process of hormonally defined medium (HDM) and serum-containing medium.

METHODS

Formation of RPE tight junctions was analyzed in freshly isolated rat RPE cells maintained either in HDM or serum-containing medium. Junctions were evaluated functionally by measuring transepithelial electrical resistance (TER) and permeability and structurally by immunolocalization of the junction-associated actin microfilaments. Calcium dependency of the junctions was determined by reducing media calcium concentration.

RESULTS

RPE cells cultured in serum-free HDM developed calcium-dependent tight junctions, which exhibited TER levels > 150 omega cm2 and low paracellular permeability. Serum-containing media inhibited tight junction formation as indicated by significant reductions in TER and increases in permeability. Junction-associated actin microfilaments and cell density were unchanged.

CONCLUSIONS

Tight junction formation by RPE cells is inhibited by serum. This activity may play an important role in responses of the RPE layer to injury, contributing to the pathologic progression of blood-retinal barrier dysfunction.

Cloning and sequencing of a cDNA for firefly luciferase from Photuris pennsylvanica

The first cDNA from the Photurinae subfamily of the Lampyridae encoding a firefly luciferase from lantern mRNA of Photuris pennsylvanica has been cloned, sequenced, the amino-acid sequence predicted and the sequence reported to GenBank. The cDNA was about 1.8 kb in length with the largest open reading frame coding for a 545-residue protein. The 5' noncoding region is 61 bp long and the 3' noncoding region is 135 bp in length. There is a 24-nucleotide poly(A) tail. When the amino-acid residues are aligned, P. pennsylvanica contains 154 (about 28% of the total residues) that are conserved in all 16 of the deduced luciferase sequences that are presently available. In this P. pennsylvanica luciferase, the amino acids at 276 of the positions are the same at corresponding positions of at least one of the other enzymes. There are two amino-acid differences between this luciferase and the unpublished sequence obtained by Dr. Keith Wood for a putative larval Photuris firefly luciferase cloned from a Maryland firefly. Signature amino-acid sequences and domains found in the deduced sequence are for adenylate kinase, the putative AMP-binding domain, luciferin 4-monooxygenase, 4-coumarate CoA ligase, long-chain fatty acid CoA ligase, 2-acylglycerophosphoethanolamine acyltransferase, the microbody-directing sequence, peptide-synthesizing complexes, and acyladenylate-synthesizing enzymes.

Photon absorption coefficient and the Franz-Keldysh shift of cutoff wavelength for mercury cadmium telluride detectors

Based on the calculation of photon absorption coefficient alpha and width W of the depletion region of mercury cadmium telluride detectors, we derived the equation for alpha, W and the effective Franz-Keldysh shift Dlambda(ce). An interpretation of the substantial difference between Dlambda(ce) and the maximum Franz-Keldysh shift Dlambda(cm) of the cutoff wavelength is presented. We also propose a method to increase the Dlambda(ce) of mercury cadmium telluride detectors.

A high-density STS map based on a single contig of YAC and P1 clones in the chromosome 8p12-p21 region

We have constructed a yeast artificial chromosome (YAC) and P1 contig in the 8p12-p21 region. The contig comprises 16 overlapping YAC clones and 44 overlapping P1 clones. Twelve dinucleotide-repeat polymorphic sequence-tagged site (STS)-markers that were previously isolated mainly from these YAC and P1 clones were genetically mapped. A total of 46 nonpolymorphic STS markers were newly established mainly from the YAC and P1 clone end fragments, and 28 of the 46 nonpolymorphic STSs, as well as the 12 polymorphic STSs, were also mapped physically onto the contig based on STS content analysis of YAC pools and of the P1 and YAC clones. As a result, the YAC and P1 clones were assembled into a single contig covering a minimum of 1.5 Mb physically and 2.8 cM genetically with 12 polymorphic and 28 nonpolymorphic STSs within the 8p12-p21 region. Average STS spacing in the contig was estimated to be 40 kb/STS. In addition, further characterization of the contig suggested that this contig includes a region where genetic recombination occurs frequently. Thus, the resulting cloned region, together with densely mapped STS markers on the contig, should help to promote our understanding of this region.

Association of a polymorphic variant of the Werner helicase gene with myocardial infarction in a Japanese population

The Werner syndrome (WS) is a rare autosomal recessive progeroid syndrome characterized by the premature onset of multiple age-related disorders, including atherosclerosis, cancer, non-insulin-dependent diabetes mellitus (NIDDM), ocular cataracts and osteoporosis [Epstein et al., 1966]. The major cause of death (at a median age of 47) is myocardial infarction (MI) [Epstein et al., 1966]. The WS mutation involves a member (WRN) of the RecQ family of helicases and may perturb DNA replication, repair, recombination, transcription, or chromosomal segregation [Yu et al., 1996]. We now report data on 149 MI cases and age-matched controls suggesting that a polymorphic WRN variant is associated with increased risk for MI. Based on our data, homozygosity for a cysteine at amino acid 1367 (the most prevalent genotype) predicts a 2.78 times greater risk of MI (95% confidence intervals: 1.23 to 6.86). The variant was not significantly associated with NIDDM. The two alleles (cysteine vs. arginine) could influence helicase activity, turnover, macromolecular interactions or, alternatively, could be markers for haplotypes influencing WRN regulation or reflecting gene action at linked loci. However, given the caveats implicit in genetic association studies, it is imperative that the present results be replicated in independent populations.

A home electrocardiography and blood pressure telemonitoring system

A home electrocardiography (ECG) and blood pressure telemonitoring system for cardiac patients was installed in the Macau region. The monitoring centre was established in the emergency unit at the Government Hospital of Macau. The first users were 10 cardiovascular patients selected by a physician. The average age of these users was 61 years (range 30-78). The results of a three-month trial showed that the system was easy to operate and technically reliable. It was found to be helpful for cardiac patients. The most significant problem during the trial was electrical noise from the ECG electrodes.

Narrowing the position of the Werner syndrome locus by homozygosity analysis-extension of homozygosity analysis

Werner syndrome (WS) is an autosomal recessive disorder characterized by the premature occurrence of many age-related features. Previously, the WS gene (WRN) was mapped between D8S131 and D8S87, in an 8.3-cM interval. In this study, regions of homozygosity in 36 WS patients from inbred families were searched for by genotyping for 35 dinucleotide repeat polymorphic markers to narrow down the WRN critical region. The region most consistently homozygous in these patients was between the D8S1219/D8S1220 cluster and D8S278, within a 4.4-cM interval. For 16 markers mapped in this interval, 24 WS patients (22 Japanese patients and 2 Caucasian patients) in whom consanguinity failed to be proved were also genotyped, under the assumption that some of these patients might still be from consanguineous marriages. The data were analyzed by Fisher's exact test with a 2 x 2 contingency table for the 22 Japanese patients, excluding the 2 Caucasian patients. The frequencies of homozygosity in the 22 patients at 10 of 16 markers tested were significantly higher than those detected in the general population. Analysis of homozygosity patterns indicated that the region most consistently homozygous was between D8S1445 and D8S278. Thus the WRN locus is most likely between the two markers D8S1445 and D8S278, in a 1.6-cM interval.

Artificial antibodies to corticosteroids prepared by molecular imprinting

BACKGROUND

Molecular imprinting can be used to prepare antibody and receptor mimics. We have previously shown that acrylic acid polymers can be imprinted to recognize a variety of small molecules. Here, we show that molecularly imprinted polymers (MIPs) can selectively recognize steroid structures.

RESULTS

Artificial antibodies mimicking the binding performance of natural anti-corticosteroid antibodies have been prepared using a molecular imprinting protocol with either cortisol or corticosterone as a target molecule. The binding characteristics of a range of structurally related ligands were estimated using a form of radioimmunoassay. The antibody mimics were found to be highly selective for the ligands used in their preparation and the cross-reactivities with compounds of related structure resembled those obtained in studies with natural antibodies.

CONCLUSIONS

The binding properties of MIPs, prepared against corticosteroids, exhibit strong similarities to those of naturally raised antibodies. Such artificial antibodies may serve as a useful complement to their natural counterparts in studies of corticosteroid binding events.