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W He

Publications and source records attributed to W He.

At least 109 records · Page 6Linked to original sources
PubMed1999

Structure, alternative splicing, and expression of the human RGS9 gene.

An isoform of RGS9 was recently identified as the GTPase activating protein in bovine and mouse rod and cone photoreceptors. To explore the potential role of the RGS9 gene in human retinal disease, we determined its exon/intron arrangement, and investigated its expression in human retina. The results show that the gene, located on 17q24, consists of 19 exons and spans more than 75kb of genomic DNA. The entire gene was found to be contained on a single BAC clone with an insert size of 170kb. The major transcripts of the gene are alternatively spliced into a 9.5kb retina-specific transcript (RGS9-1) and a brain specific 2.5kb transcript (RGS9-2). Exons 1-16 are constitutive and present in both variants. Exon 17 contains the 3' end of the open reading frame and the 3'-UTR of the RGS9-1 variant. In RGS9-2, exon 17 is alternatively spliced and joined to exons 18 and 19 that are not present in the retina variant. Immunolocalization with a monoclonal antibody recognizing the retina and brain variants shows abundant expression in photoreceptors and possibly very low levels in cell types of the inner retina. Owing to the specific expression of RGS9-1 in photoreceptors the RGS9 gene is a candidate gene for RP17, a form of autosomal retinitis pigmentosa, located on the long arm of chromosome 17.

Aged↗
PubMed1999

The human homologue of the yeast proteins Skb1 and Hsl7p interacts with Jak kinases and contains protein methyltransferase activity.

To expand our understanding of the role of Jak2 in cellular signaling, we used the yeast two-hybrid system to identify Jak2-interacting proteins. One of the clones identified represents a human homologue of the Schizosaccaromyces pombe Shk1 kinase-binding protein 1, Skb1, and the protein encoded by the Saccharomyces cerevisiae HSL7 (histone synthetic lethal 7) gene. Since no functional motifs or biochemical activities for this protein or its homologues had been reported, we sought to determine a biochemical function for this human protein. We demonstrate that this protein is a protein methyltransferase. This protein, designated JBP1 (Jak-binding protein 1), and its homologues contain motifs conserved among protein methyltransferases. JBP1 can be cross-linked to radiolabeled S-adenosylmethionine (AdoMet) and methylates histones (H2A and H4) and myelin basic protein. Mutants containing substitutions within a conserved region likely to be involved in AdoMet binding exhibit little or no activity. We mapped the JBP1 gene to chromosome 14q11.2-21. In addition, JBP1 co-immunoprecipitates with several other proteins, which serve as methyl group acceptors and which may represent physiological targets of this methyltransferase. Messenger RNA for JBP1 is widely expressed in human tissues. We have also identified and sequenced a homologue of JBP1 in Drosophila melanogaster. This report provides a clue to the biochemical function for this conserved protein and suggests that protein methyltransferases may have a role in cellular signaling.

Amino Acid Sequence↗
PubMed1999

The A beta 3-pyroglutamyl and 11-pyroglutamyl peptides found in senile plaque have greater beta-sheet forming and aggregation propensities in vitro than full-length A beta.

A beta isolated from neuritic plaque and vascular walls of the brains of patients with Alzheimer's disease has been shown to contain significant quantities of A beta peptides which begin at residue 3Glu or 11Glu in the form of pyroglutamyl residues (A beta 3pE and A beta 11pE). To investigate the effects of these N-terminal modifications on the biophysical properties of A beta, peptides A beta 1-40, A beta 3pE-40, A beta 11pE-40, A beta 1-28, A beta 3pE-28, and A beta 11pE-28 were synthesized. Using circular dichroism spectroscopy, we determined that the pyroglutamyl-containing peptides form beta-sheet structure more readily than the corresponding full-length A beta peptides, both in aqueous solutions and in 10% sodium dodecyl sulfate micelles. Trifluoroethanol spectra indicated that the relative beta-sheet to alpha-helical stability is higher for the pyroglutamyl-containing peptides. Sedimentation experiments show that the pyroglutamyl-containing peptides have greater aggregation propensities than the corresponding full-length peptides. Comparison between the A beta 40 and the A beta 28 series indicated that the greater beta-sheet forming and aggregation propensities of the pyroglutamyl peptides are not simply due to an increase in hydrophobicity.

Alzheimer Disease↗
PubMed1999

Cloning and characterization of RGS9-2: a striatal-enriched alternatively spliced product of the RGS9 gene.

Regulators of G-protein signaling (RGS) proteins act as GTPase-activating proteins (GAPs) for alpha subunits of heterotrimeric G-proteins. Previous in situ hybridization analysis of mRNAs encoding RGS3-RGS11 revealed region-specific expression patterns in rat brain. RGS9 showed a particularly striking pattern of almost exclusive enrichment in striatum. In a parallel study, RGS9 cDNA, here referred to as RGS9-1, was cloned from retinal cDNA libraries, and the encoded protein was identified as a GAP for transducin (Galphat) in rod outer segments. In the present study we identify a novel splice variant of RGS9, RGS9-2, cloned from a mouse forebrain cDNA library, which encodes a striatal-specific isoform of the protein. RGS9-2 is 191 amino acids longer than the retinal isoform, has a unique 3' untranslated region, and is highly enriched in striatum, with much lower levels seen in other brain regions and no expression detectable in retina. Immunohistochemistry showed that RGS9-2 protein is restricted to striatal neuropil and absent in striatal terminal fields. The functional activity of RGS9-2 is supported by the finding that it, but not RGS9-1, dampens the Gi/o-coupled mu-opioid receptor response in vitro. Characterization of a bacterial artificial chromosome genomic clone of approximately 200 kb indicates that these isoforms represent alternatively spliced mRNAs from a single gene and that the RGS domain, conserved among all known RGS members, is encoded over three distinct exons. The distinct C-terminal domains of RGS9-2 and RGS9-1 presumably contribute to unique regulatory properties in the neural and retinal cells in which these proteins are selectively expressed.

Alternative Splicing↗
PubMed1999

Analysis of mRNA decay pathways in Saccharomyces cerevisiae.

The analysis of mRNA turnover often requires a knowledge of the pathway by which a particular mRNA is being degraded. In this article we describe experimental procedures that can be used to determine the mechanism of degradation for yeast transcripts. These approaches include the insertion of strong secondary structures to block exonuclease cleavage and thereby trap decay intermediates. In addition, mRNA decay pathways can be analyzed by using regulatable promoters to perform transcriptional pulse-chase experiments, thereby allowing the determination of precursor-product relationships during the mRNA decay process. Finally, the mechanism of mRNA degradation can also now be determined by using trans-acting mutations specific for distinct mRNA turnover pathways. Most importantly, the combination of these three approaches can often clearly define the mechanism(s) by which a given transcript is degraded.

Genes, Fungal↗
PubMed1999

109 cases of blepharoptosis treated by forked frontalis muscle aponeurosis procedure with long term follow-up.

109 cases of severe or recurrent blepharoptosis have been treated with the forked frontalis muscle aponeurosis (FFMA) technique since 1989. In comparison with other frontalis muscle flap (FMF) protocols, this technique has three advantages: (i) no skin incision in the lower rim of the eyebrow; (ii) no incision in the frontalis muscle; and (iii) no dissection under the frontalis muscle. The FFMA is formed at the junction of the frontalis and orbicularis muscles. The 9-year follow-up shows that this is a highly effective procedure. The postoperative function of the frontalis muscle is good and the lack of damage has been confirmed by EMG. There are a few complications such as the sluggishness of the upper eyelid on downward gaze and the possibility of asymmetrical brow height in unilateral blepharoptosis. However, this technique may serve as the best choice in the treatment of severe or recurrent blepharoptosis.

Adolescent↗
PubMed1999

Generation of powerful subnanosecond microwave pulses by intense electron bunches moving in a periodic backward wave structure in the superradiative regime.

Experimental results of the observation of coherent stimulated radiation from subnanosecond electron bunches moving through a periodic waveguide and interacting with a backward propagating wave are presented. The subnanosecond microwave pulses in Ka and W bands were generated with repetition frequencies of up to 25 Hz. The mechanism of microwave pulse generation was associated with self-bunching, and the mutual influence of different parts of the electron pulse due to slippage of the wave with respect to the electrons; this can be interpreted as superradiance. The illumination of a panel of neon bulbs resulted in a finely structured pattern corresponding to the excitation of the TM01 mode. Observation of rf breakdown of ambient air, as well as direct measurements by hot-carrier germanium detectors, leads to an estimate of the absolute peak power as high as 60 MW for the 300-ps pulses at 38 GHz. These results are compared with numerical simulations. The initial observation of 75-GHz, 10-15-MW radiation pulses with a duration of less than 150 ps is also reported.

Journal Article↗
PubMed1999

Expansion and immunological study of human tumor infiltrating gamma/delta T lymphocytes in vitro.

Goffa/delta T cells have stimulated a lot of interest because of their unique features in antigen recognition and cytotoxicities to many autologous and/or allogeneic tumor cells. We have developed a novel method to selectively expand larger amounts of human tumor-infiltrating gamma/delta T lymphocytes (gamma/delta TILs) ex vivo by immobilized pan- anti-TCRgamma/delta monoclonal antibody in the presence of exogenous IL-2. The expanded gamma/delta TILs mainly expressed CD45RO and HLA-DR molecules and did not express CD4. CD8+ gamma/delta TILs accounted for 19% of gamma/delta TILs. The expression of CD25 molecule on expanded gamma/delta T cells was inducible and downregulated following a time course. The Vdelta1 and Vdelta2 subsets amount to 37 and 58%, respectively. The expanded gamma/delta TILs show an IL-2-dependent proliferation, MHC class I-unrestricted and TCRgamma/delta-related cytotoxicities to two MHC class I+ and two MHC class I+ allogeneic tumor cell lines in vitro.

Adenocarcinoma↗
PubMed1999

The type I serine/threonine kinase receptor ActRIA (ALK2) is required for gastrulation of the mouse embryo.

ActRIA (or ALK2), one of the type I receptors of the transforming growth factor-beta (TGF-beta) superfamily, can bind both activin and bone morphogenetic proteins (BMPs) in conjunction with the activin and BMP type II receptors, respectively. In mice, ActRIA is expressed primarily in the extraembryonic visceral endoderm before gastrulation and later in both embryonic and extraembryonic cells during gastrulation. To elucidate its function in mouse development, we disrupted the transmembrane domain of ActRIA by gene targeting. We showed that embryos homozygous for the mutation were arrested at the early gastrulation stage, displaying abnormal visceral endoderm morphology and severe disruption of mesoderm formation. To determine in which germ layer ActRIA functions during gastrulation, we performed reciprocal chimera analyses. (1) Homozygous mutant ES cells injected into wild-type blastocysts were able to contribute to all three definitive germ layers in chimeric embryos. However, a high contribution of mutant ES cells in chimeras disrupted normal development at the early somite stage. (2) Consistent with ActRIA expression in the extraembryonic cells, wild-type ES cells failed to rescue the gastrulation defect in chimeras in which the extraembryonic ectoderm and visceral endoderm were derived from homozygous mutant blastocysts. Furthermore, expression of HNF4, a key visceral endoderm-specific transcription regulatory factor, was significantly reduced in the mutant embryos. Together, our results indicate that ActRIA in extraembryonic cells plays a major role in early gastrulation, whereas ActRIA function is also required in embryonic tissues during later development in mice.

Activin Receptors, Type I↗
PubMed1999

Cell-specific expression of tubby gene family members (tub, Tulp1,2, and 3) in the retina.

PURPOSE: The family of tubby-like proteins (TULPs), consisting of four family members, are all expressed in-the retina at varying levels. Mutations within two members, tub and TULP1, are known to lead to retinal degeneration in mouse and humans, respectively, suggesting the functional importance of this family of proteins in the retina. Despite a high degree of conservation in the carboxy-terminal region (e.g., putative functional domain of the genes) among family members, they are unable to compensate for one another. The purpose of this study was to provide a rationale for this lack of compensation by investigating the spatial distribution of tubby gene family members in the retina and to investigate the mechanism of photoreceptor cell death in tubby mice. METHODS: In situ hybridization using riboprobes specific for each tubby gene family member and immunohistochemistry for TUB and TULP1 were performed to determine their expression patterns in the retina of tubby and wild-type control mice. The terminal dUTP nick-end labeling (TUNEL) assay was performed to detect apoptotic cells in the retina of tubby and wild-type control mice. RESULTS: tub mRNA was found to be expressed throughout the retina, with highest expression in the ganglion cell layer (GCL) and photoreceptor cells. In contrast, Tulp1 expression was observed only in photoreceptor cells and Tulp3 mRNA was expressed at a moderate level only in the inner nuclear layer (INL) and GCL. The results of the immunohistochemical analysis paralleled those observed in the in situ studies. TUB immunoreactivity was most highly concentrated in the GCL, in the inner and outermost regions of the INL, in the outer plexiform layer (OPL), and in the inner segments of photoreceptor cells. Similarly, TULP1 immunoreactivity was observed in the OPL and inner segments of the photoreceptor cells. No differences in expression at the mRNA or protein level were observed for any of the molecules tested in tubby or wild-type mice. TUNEL-positive cells were detected in the ONL of tubby mice, whereas very few were seen in the same layer of age-matched control mice. CONCLUSIONS: Although all tubby gene family members are expressed in the retina, they each have different cell-specific expression patterns, which may account in part for their inability to compensate for the loss of one family member. The photoreceptor cell death in tubby mice occurs through an apoptotic mechanism, which is known to be the common final outcome of other forms of retinal degeneration.

Adaptor Proteins, Signal Transducing↗
PubMed1999

[Adenosine is effective to improve the viability of the transverse rectus abdominis myocutaneous (TRAM) flap in the pig].

OBJECTIVE: The aim of this experiment was to investigate the adenosine treatment for augmentation of TRAM flap viability in pigs. METHODS: This TRAM flap model was based on the deep inferior epigastric vascular pedicle, with the center of the transverse skin pedicle attached to the underlying rectus abdominis muscle at the superior end of the muscle and extending bilaterally from its attached muscle. The transverse skin pedicle (6 x 30 cm) included a contralateral and ipsilateral random portion of skin. Prior to raising the TRAM flap, 1 mg, 2 mg or 5 mg adenosine was injected through the superior epigastric artery in the experiment group. RESULTS: Treatment with 2 mg or 5 mg adenosine increased skin viability of the transverse skin flap in the experiment group compared with the sham-operated control (P < 0.05, n = 5). CONCLUSION: Adenosine treatment through a dominant vascular pedicle prior to raising the TRAM flap is effective in augmenting skin viability of the flap.

Abdominal Muscles↗
PubMed1999

[Acute ischemic preconditioning protects against skeletal muscle infarction in the pig].

OBJECTIVE: The aim of this study was to investigate metabolism of ischemic muscle and the efficacy of acute ischemic preconditioning for protection of skeletal muscles against infarction. METHODS: The efficacy of preconditioning was tested by subjecting pig latissimus dorsi muscle to 3 cycles of ischemia reperfusion, each for 10 min, before 4 h of global ischemia. Infarction was assessed at 48 h reperfusion using nitroblue tetrazolium dye. Muscle biopsies were taken from the latissimus dorsi before ischemia, at the end of 2 and 4 h of ischemia and 1.5 h of reperfusion. RESULTS: Preconditioning reduced the total infarct size by 44% in the latissimus dorsi. The muscle contents of ATP were maintained higher and the lactate lower (P < 0.05) in the preconditioned than in the non-preconditioned muscle at the end of 2 h, 4 h of ischemia and 1.5 h of reperfusion. CONCLUSION: Preconditioning of pig skeletal muscle is associated with a lower energy metabolism during sustained ischemia. At the present time, it is not known if this energy sparing effect is a major mechanism of ischemia preconditioning against infarction in the skeletal muscle.

Animals↗
PubMed1999

[Diagnosis and treatment of true hermaphroditism: a report of 3 cases and a review of literature].

OBJECTIVE: This paper evaluates the importance of early diagnosis and systemic treatment of true hermaphroditism. METHODS: Three patients with true hermaphroditism, because of inaccurate diagnosis and improper treatment at their early ages, were put in a dilemma when they grew up. After correct diagnosis, they accepted sex determinative operations according to their selective gender role. RESULTS: Through plastic operations, the three patients turned to be a male and two females, with their long time depression being released. CONCLUSION: True hermaphroditism is a rare deformity of ambiguous genitalia characterised by the presence of both ovarian and testicular tissues in the same individual. It is a key point for the patient to form normal sex psyche and adapt society through early precise diagnosis, appropriate gender option and successful operation according to clinical appearances and tissue pathological examination.

Adult↗
PubMed1999

[Clinical and experimental study on effect of burn Jinhuang liquid in treating wound of II degree of burns].

OBJECTIVE: To explore therapeutic effect of Chinese herbal drug Burn Jinhuang Liquid (BJHL) in treating II degree (II- and II+ degree) burn injury. METHODS: One hundred and twenty II degree burn patients were treated with BJHL, the clinical effect was compared with that of moist exposure burn ointment (MEBO). Animal experiments on the effect of BJHL were conducted. RESULTS: To compare with MEBO, BJHL has a better effect of bacteria inhibition and declining rate of wound infection and shortening time of wound healing through clinical and experimental study. There was no irritation to the burn wound, and it has no side and toxic effects to the liver and kidney. CONCLUSION: BJHL has a comprehensive effect of bacteria inhibition, analgesis and wound healing improvement.

Adolescent↗
PubMed1999

[Rat submandibular gland tumor induced by 3-methylcholanthrene].

OBJECTIVE: To study the genesis and the development of salivary gland tumor (SGT). METHODS: SGT animal models were established by injection of 3-methylcholanthrene (3-MCA) oil solution into 40 submandibular glands of Sprague-Dawley (SD) rats, then histopathology and ultrastructure of induced tumors were observed under microscope, and immunohistochemical detection of keratin and actin was carried out. RESULTS: 32 models of submandibular gland tumors were induced successfully, with 4 rats of squamous cell carcinoma and 28 leiomyosarcoma, and the carcinogenesis of 3-MCA and tissue genesis of induced tumors were discussed. CONCLUSION: Submandibular gland tumor can be induced by 3-MCA, and sarcoma was of high incidence.

Animals↗
PubMed1999

[Effects of human thorax tissues on conduction of electrocardiogram and body surface potential].

In this paper, the forward problem of electrocardiogram(ECG) has been calculated by means of numerical simulating techniques. Firstly, It is focused on the effects of organs and tissues within the thorax on the body surface potentials under a 2-D cross section of thorax in terms of finite element method (FEM). To check the effect of skeletal muscle layers on ECG, the simulating computation of ECG, by a method combining FEM with boundary element method (BEM), has been carried out in terms of a 3-D thorax model.

Algorithms↗