Effects of Chinese herbal prescriptions on copulatory activity in aged male rats: a preliminary study

Four herbal prescription medicines, Chi-Pao-Mei-Jan-Tan, Gui-Fu-Ba-Wei-Wan, Huan-Shao-Tan; and San Tsai-Feng-Sui-Tan, were tested for their effects on sexual behavior in aged rats. Crude liquid extracts of these herbs were administered to the rats daily through oral tubing for 14 days. All four herbal prescriptions showed some effects in restoration of mount and intromission behaviors, but there was no effect on restoration of ejaculation in 26 month old rats that had exhibited no copulatory activity (no mount, intromission and ejaculation) previously. The effects of Chi-Pao-Mei-Jan-Tan were further tested in 26 month old rats with low mount and intromission activities but without ejaculation behavior, and in 15 month old rats (middle-age group) that showed normal mount and intromission behavior but no ejaculation activity. Chi-Pao-Mei-Jan-Tan was effective in improving the frequency of both mount and intromission, but failed to restore the ejaculation activity of the old rats with low mount and intromission behaviors. It was, however, very effective in restoration of ejaculation activity in middle-aged rats that exhibited normal mount and intromission behaviors. Serum testosterone (T) levels of Chi-Pao-Mei-Jan-Tan in tested old and middle-aged rats were determined by radioimmunoassay, and showed no difference before and after treatment. Our findings demonstrated that the four herbal prescriptions had some effects in restoration of mount and intromission behaviors, but not ejaculation activity in old rats, and that Chi-Pao-Mei-Jan-Tan was very effective in restoration of ejaculation activity in middle-aged rats. The promotional effect of Chi-Pao-Mei-Jan-Tan on copulatory behavior was not correlated with serum T levels.

One of the CD3epsilon subunits within a T cell receptor complex lies in close proximity to the Cbeta FG loop

A recent crystal structure of the N15 alpha/beta-T cell receptor (TCR) in complex with an Fab derived from the H57 Cbeta-specific monoclonal antibody (mAb) shows the mAb fragment interacting with the elongated FG loop of the Cbeta domain. This loop creates one side wall of a cavity within the TCR Ti-alpha/beta constant region module (CalphaCbeta) while the CD and EF loops of the Calpha domain form another wall. The cavity size is sufficient to accommodate a single nonglycosylated Ig domain such as the CD3epsilon ectodomain. By using specific mAbs to mouse TCR-beta (H57) and CD3epsilon (2C11) subunits, we herein provide evidence that only one of the two CD3epsilon chains within the TCR complex is located in close proximity to the TCR Cbeta FG loop, in support of the above notion. Moreover, analysis of T cells isolated from transgenic mice expressing both human and mouse CD3epsilon genes shows that the heterologous human CD3epsilon component can replace the mouse CD3epsilon at this site. The location of one CD3epsilon subunit within the rigid constant domain module has implications for the mechanism of signal transduction throughout T cell development.

The peptidyl-prolyl isomerase domain of the CyP-40 cyclophilin homolog Cpr7 is not required to support growth or glucocorticoid receptor activity in Saccharomyces cerevisiae

CyP-40 cyclophilins are found in association with molecular chaperone Hsp90.steroid receptor complexes. The amino-terminal portion of these cyclophilins harbors the characteristic peptidyl-prolyl isomerase (PPIase) domain, whereas three copies of the tetratricopeptide (TPR) motif, a structure shown to be involved in protein-protein interactions, and a putative calmodulin-binding domain are located in the carboxyl-terminal half of the protein. The TPR domains mediate binding to Hsp90, but a requirement for the PPIase domain has not been established. To address this, we have investigated the effects of mutations that alter the PPIase domain of the Saccharomyces cerevisiae CyP-40 homolog, Cpr7. Because Cpr7 is required for rapid growth and full Hsp90 activity, a functional assessment of the PPIase domain could be performed in vivo. A mutation in the catalytic domain altering a conserved site predicted to be essential for isomerase activity did not compromise Cpr7 function. Furthermore, deletion of the entire PPIase domain did not significantly affect growth or Hsp90-mediated steroid receptor activity. These results indicate that the TPR-containing carboxyl terminus of Cpr7 is sufficient for fundamental Cpr7-dependent activity.

Determination of acceptability of flavored oat bran frankfurters by older adults

The US population is aging rapidly and, within the next 25 years, 20-25% will be over age 60. This creates a vast new market for age-specific products and increases the responsibility of food scientists and nutritionists to provide appropriate foods for older adults. Many older individuals are energy deficient and need to be encouraged to consume more food in order to maintain body weight and health, but need to decrease the calories from fat in their diets. Many of these older individuals are not inclined to eat foods that they enjoy for fear that these foods may be detrimental to their health (de Castro, 1993), or they have lost their gustational abilities to the degree that these foods are no longer enjoyable. This research looks at a possible solution to both problems by replacing fat in a favorite food of older adults and adjusting the flavor levels of this product. Frankfurters were made from mechanically deboned poultry meat in which standard commercial formulation was compared to three flavoring treatments using oat bran as a fat replacer (6% oat bran, 30% H2O). Mixed spices (traditional saucisson) were added to two of these treatments in standard and double proportions. Participants were 71 individuals over the age of 65 in varying levels of health from four regional care facilities. Seven gram, three-digit-coded samples were evaluated at 60 degrees C, and scored on a nine-point hedonic scale. A significant (alpha = 0.0004) preference was shown for the double-spiced frank. No differences by sex or race were found. Research concluded that addition of flavoring aids in the increased acceptability of products by older adults.

Peroxidase-catalyzed oxidation of 2,4,6-trichlorophenol

2,4,6-Trichlorophenol (TCP) is an environmental contaminant that is toxic, mutagenic, and carcinogenic. We have investigated peroxidase-catalyzed oxidation of TCP as an alternative pathway of TCP bioactivation using horseradish peroxidase (HRP) as a model peroxidase. TCP was shown to function as a reducing substarte for HRP as evidenced by TCP-dependent, HRP-catalyzed reduction of 5-phenyl-4-penten-1-yl hydroperoxide (PPHP) to its corresponding alcohol. In addition, TCP was shown to undergo hydroperoxide (H2O2, ethyl hydroperoxide, or PPHP)-dependent metabolism as evidenced by electronic absorption spectroscopic analysis of reaction mixtures. A single major product was detected by reverse phase HPLC and was identified as 2,6-dichloro-1,4-benzoquinone (2,6-dichloro-2, 5-cyclohexadiene-1,4-dione, CAS no. 697-91-6) on the basis of electronic absorption spectroscopy, mass spectrometry, and cochromatography with synthetic standard. In addition, HRP-catalyzed oxidation of TCP yielded EPR-detectable phenoxyl radical intermediates whose EPR spectrum consisted of a 1:2:1 triplet characterized by proton hyperfine coupling constants aH(3,5) = 2.35 gauss. Mechanisms for the hydroperoxide-dependent, HRP-catalyzed oxidation of TCP are proposed that are consistent with these results.

Identification of a common docking topology with substantial variation among different TCR-peptide-MHC complexes

Whether T-cell receptors (TCRs) recognize antigenic peptides bound to major histocompatability complex (MHC) molecules through common or distinct docking modes is currently uncertain. We report the crystal structure of a complex between the murine N15 TCR [1-4] and its peptide-MHC ligand, an octapeptide fragment representing amino acids 52-59 of the vesicular stomatitis virus nuclear capsid protein (VSV8) bound to the murine H-2Kb class I MHC molecule. Comparison of the structure of the N15 TCR-VSV8-H-2Kb complex with the murine 2C TCR-dEV8-H-2Kb [5] and the human A6 TCR-Tax-HLA-A2 [6] complexes revealed a common docking mode, regardless of TCR specificity or species origin, in which the TCR variable Valpha domain overlies the MHC alpha2 helix and the Vbeta domain overlies the MHC alpha1 helix. As a consequence, the complementary determining regions CDR1 and CDR3 of the TCR Valpha and Vbeta domains make the major contacts with the peptide, while the CDR2 loops interact primarily with the MHC. Nonetheless, in terms of the details of the relative orientation and disposition of binding, there is substantial variation in TCR parameters, which we term twist, tilt and shift, and which define the variation of the V module of the TCR relative to the MHC antigen-binding groove.

Sialadenoma papilliferum of the esophagus

Sialadenoma papilliferum is an extremely rare benign tumor of the esophagus. We report a 70-yr-old woman who was first thought to have adenocarcinoma in the distal esophagus. Transhiatal esophagectomy and left colon interposition were performed. The pathological diagnosis of sialadenoma papilliferum of the esophagus arising in the submucosal gland ducts was confirmed after surgery.

Comparison of hemodynamics and recovery of sevoflurane and isoflurane anesthesia in Chinese adult patients

BACKGROUND

The new inhalational anesthetic sevoflurane would be expected to provide a rapid emergence from anesthesia due to its low blood/gas partition coefficient. In this study, we compared the hemodynamic effects, speed and quality of emergence, in ASA class I-II Chinese adult surgical patients receiving either sevoflurane or isoflurane anesthesia.

METHODS

Eighty adult Chinese patients, ASA class I-II, scheduled for elective gynecological or general surgical procedures, were randomized to receive sevoflurane (n = 40) or isoflurane (n = 40) anesthesia. Ventilation is controlled via endotracheal intubation with anesthesia facilitated by either agent at anesthetic concentration of 1-1.5 MAC under the fresh gas flow 2 L/min. Heart rate, arterial blood pressure, temperature, SpO2 and end-tidal CO2 were continuously monitored. Any adverse effect such as airway irritation, nausea or vomiting was recorded during induction and emergence from anesthesia. The emergence time was assessed by various questionales for orientation during recovery. In the post-anesthetic recovery period, pain was monitored and managed by objective pain discomfort scale for analgesic supplements. Complaints of nausea and vomiting were recorded and followed up by a research nurse who visited the patient within 24 h following surgery.

RESULTS

The extent of exposure to anesthetic (MAC x hours) was similar in both groups. Sevoflurane and isoflurane caused similar alterations in systolic and diastolic arterial pressure during maintenance. After surgical incision, the heart rate accelerated more in patients receiving isoflurane (p < 0.05). During emergence, time of response to command was significantly shorter in patients receiving sevoflurane than patients receiving isoflurane (5.6 +/- 0.4 min versus 15.2 +/- 3.0 min, p < 0.001). Side effects such as nausea and vomiting were comparable in both groups.

CONCLUSIONS

Compared with isoflurane, sevoflurane anesthesia had the clinical advantages of maintaining stable hemodynamics and rapid recovery in Chinese adult patients.

A piezoelectric quartz crystal sensor for the determination of coagulation time in plasma and whole blood

A Peizoelectric Quartz Crystal (PQC) system possessing an adequate sensitivity to a slight viscosity change is employed to monitor the blood coagulation. In the case of an anticoagulated plasma specimen, prothrombin time (PT) was determined by the PQC sensor on the basis of the introduction of tissue thromboplastin (TF) and calcium ion. Discussing the PQC data statistically, we found that at 90% of the total frequency shift (delta f) the best linear relationship in a double-logarithmic plot of PT versus TF concentration in the range of 5.466-22.311 unit/ml is shown. The PQC result was compared with commercial optical coagulometry and showed a good linear correlation (ca. 0.98). The clotting and recalcification of whole blood were also studied by the PQC system. The testing time for one measurement could be completed within 20 min. and had a good agreement with that obtained conventionally.

Pregnancy achieved by intracytoplasmic sperm injection using cryopreserved vasal-epididymal sperm from a man with spinal cord injury

Anejaculation and poor semen quality are two major causes of infertility in men with spinal cord injury (SCI). The poor motility of retrieved sperm usually has low fertilization potential and is thought to be unfavorable for cryopreservation. This report describes a pregnancy after intracytoplasmic sperm injection (ICSI) with cryopreserved vasal-epididymal sperm from a man with SCI and anejaculation. An attempt was made to obtain sperm through electroejaculation, but no motile sperm were found in two trials. Therefore, the subject underwent vasal aspiration. The retrieved sperm had a concentration of 26 x 10(6)/mL and a motility of 3%. ICSI was considered to be the best choice for the couple, but the wife did not become pregnant in the first cycle of treatment. A successful pregnancy was achieved by ICSI in the second cycle using frozen-thawed sperm, supernumerary in the previous cycle, with a density of 5 x 10(6)/mL and 1% motility. A set of healthy twins, one boy and one girl, were delivered via cesarean section at 36 weeks of gestation. Complementary to other assisted reproductive techniques, ICSI may provide men with SCI a greater opportunity to father children. The supernumerary sperm, regardless of quality, should be cryopreserved to avoid the necessity and risk of repeated assisted ejaculations and aspirations of the genital tract.

Atomic structure of an alphabeta T cell receptor (TCR) heterodimer in complex with an anti-TCR fab fragment derived from a mitogenic antibody

Each T cell receptor (TCR) recognizes a peptide antigen bound to a major histocompatibility complex (MHC) molecule via a clonotypic alphabeta heterodimeric structure (Ti) non-covalently associated with the monomorphic CD3 signaling components. A crystal structure of an alphabeta TCR-anti-TCR Fab complex shows an Fab fragment derived from the H57 monoclonal antibody (mAb), interacting with the elongated FG loop of the Cbeta domain, situated beneath the Vbeta domain. This loop, along with the partially exposed ABED beta sheet of Cbeta, and glycans attached to both Cbeta and Calpha domains, forms a cavity of sufficient size to accommodate a single non-glycosylated Ig domain such as the CD3epsilon ectodomain. That this asymmetrically localized site is embedded within the rigid constant domain module has implications for the mechanism of signal transduction in both TCR and pre-TCR complexes. Furthermore, quaternary structures of TCRs vary significantly even when they bind the same MHC molecule, as manifested by a unique twisting of the V module relative to the C module.

Topology of NAT2, a prototypical example of a new family of amino acid transporters

Amino acids are the predominant form of nitrogen available to the heterotrophic tissues of plants. These essential organic nutrients are transported across the plasma membrane of plant cells by proton-amino acid symporters. Our lab has cloned an amino acid transporter from Arabidopsis, NAT2/AAP1, that represents the first example of a new class of membrane transporters. We are investigating the structure and function of this porter because it is a member of a large gene family in plants and because its wide expression pattern suggests it plays a central role in resource allocation. In the results reported here, we investigated the topology of NAT2 by engineering a c-myc epitope on either the N or C terminus of the protein. We then used in vitro translation, partial digestion with proteinase K, and immunoprecipitation to identify a group of oriented peptide fragments. We modeled the topology of NAT2 based on the lengths of the peptide fragments that allowed us to estimate the location of protease accessible cleavage sites. We independently identified the location of the N and C termini using immunofluorescence microscopy of NAT2 expressed in COS-1 cells. We also investigated the glycosylation status of several sites of potential N-linked glycosylation. Based on the combined data, we propose a novel 11 transmembrane domain model with the N terminus in the cytoplasm and C terminus facing outside the cell. This model of protein topology anchors our complementary investigations of porter structure and function using site-directed and random mutagenesis.

Anti-thyroid isoflavones from soybean: isolation, characterization, and mechanisms of action

The soybean has been implicated in diet-induced goiter by many studies. The extensive consumption of soy products in infant formulas and in vegetarian diets makes it essential to define the goitrogenic potential. In this report, it was observed that an acidic methanolic extract of soybeans contains compounds that inhibit thyroid peroxidase- (TPO) catalyzed reactions essential to thyroid hormone synthesis. Analysis of the soybean extract using HPLC, UV-VIS spectrophotometry, and LC-MS led to identification of the isoflavones genistein and daidzein as major components by direct comparison with authentic standard reference isoflavones. HPLC fractionation and enzymatic assay of the soybean extract showed that the components responsible for inhibition of TPO-catalyzed reactions coeluted with daidzein and genistein. In the presence of iodide ion, genistein and daidzein blocked TPO-catalyzed tyrosine iodination by acting as alternate substrates, yielding mono-, di-, and triiodoisoflavones. Genistein also inhibited thyroxine synthesis using iodinated casein or human goiter thyroglobulin as substrates for the coupling reaction. Incubation of either isoflavone with TPO in the presence of H2O2 caused irreversible inactivation of the enzyme; however, the presence of iodide ion in the incubations completely abolished the inactivation. The IC50 values for inhibition of TPO-catalyzed reactions by genistein and daidzein were ca. 1-10 microM, concentrations that approach the total isoflavone levels (ca. 1 microM) previously measured in plasma from humans consuming soy products. Because inhibition of thyroid hormone synthesis can induce goiter and thyroid neoplasia in rodents, delineation of anti-thyroid mechanisms for soy isoflavones may be important for extrapolating goitrogenic hazards identified in chronic rodent bioassays to humans consuming soy products.

HIV-1 Tat protein exits from cells via a leaderless secretory pathway and binds to extracellular matrix-associated heparan sulfate proteoglycans through its basic region

OBJECTIVE

To analyze the mechanisms of release and the extracellular fate of the HIV-1 Tat protein and to determine the Tat domain binding to the extracellular matrix.

DESIGN AND METHODS

Release of Tat was studied by pulse-chase experiments with Tat-transfected COS-1 cells in the presence or absence of different serum concentrations, temperatures and drugs inhibiting the classical secretion pathway or endo-exocytosis, such as brefeldin A and methylamine. The binding of extracellular Tat to heparan sulfate proteoglycans (HSPG) was determined by using trypsin, heparin or heparinase in pulse-chase experiments, by gel shift and competition assays with radiolabeled heparin, and by heparin-affinity chromatography. The mapping of the Tat binding site to heparin was defined by functional assays of rescue of Tat-defective HIV-1 proviruses.

RESULTS

Tat is released in the absence of cell death or permeability changes. Tat release is dependent upon the temperature and serum concentration, and it is not blocked by brefeldin A or methylamine. After release, a portion of the protein remains in a soluble form whereas the other binds to extracellular matrix (ECM)-associated HSPG. The HSPG-bound Tat can be retrieved into a soluble form by heparin, heparinase or trypsin. Binding to heparin is competed out by heparin-binding factors such as basic fibroblast growth factor (bFGF), and it is mediated by the Tat basic region which forms a specific complex with heparin which blocks HIV-1 rescue by exogenous Tat and allows purification of a highly biologically active protein.

CONCLUSIONS

These results demonstrate that Tat exits from intact cells through a leaderless secretion pathway which shares several features with that of acid FGF or bFGF. The released Tat binds to HSPG through its basic region and this determines its storage into the ECM, as occurs for bFGF.

Identification and differentiation of bear bile used in medicinal products in Taiwan

One hundred eighty-three suspect bear bile used in medicinal products, collected in Taiwan as gall bladders or dried powder forms, were analyzed using FTIR, HPTLC, and HPLC techniques to identify whether they are indeed bear bile. Those confirmed were further examined to determine whether the observed analytical parameters can be reliably used for source inference, i.e., differentiating products among North American black bear, farmed Asiatic black bear, polar bear, etc. Our data suggested that North American and polar bears contain a higher concentration of TC (relative to TUDC and TCDC), whereas the relative concentration of TC in Asiatic bears (wild or farmed) is much lower. Thus, the relative concentration of TC can potentially be used for differentiating Asiatic bear bile from North American and polar bear products, but it cannot be used for the differentiation of wild and farmed bear bile as suggested in an earlier report by Espinoza et al. The origin of the 183 samples analyzed were found to be as follows: 118 (64%), bile salts, or gall bladders were of domestic pig; 56 (31%), bile products of Asiatic bear; 4 (2.2%), Asiatic bear mixed with pig bile salts; 3 (1.6%) goat gall bladders; 1 (0.55%) water buffalo bile salts; and 1 (0.55%), pig bile salts mixed with water buffalo bile salts.

Double-positive T cell receptor(high) thymocytes are resistant to peptide/major histocompatibility complex ligand-induced negative selection

To investigate negative selection events during intrathymic ontogeny, we established T cell receptor (TCR)-transgenic mice [N15tg/RAG-2-/- (H-2b)] expressing a single TCR specific for vesicular stomatitis virus nuclear octapeptide N52-59 (VSV8) in the context of the major histocompatibility complex (MHC) class I molecule, K(b). Administration of VSV8 in vivo induced apoptosis in less than 4 h, deleting the majority of immature double-positive (DP) thymocytes by 24 h. In contrast, DP TCRhigh as well as single-positive (SP) thymocytes were refractory to this death process. Moreover, DP TCRhigh cells differentiated into SP thymocytes in vitro and in vivo, maturing into functional cytotoxic T lymphocytes upon intrathymic transfer to beta RAG 2-/- recipients. Hence, negative selection processes involving MHC-bound peptide ligands are operative only prior to the late DP thymocyte stage in this MHC class I-restricted TCR transgene system.

Topology of T cell receptor-peptide/class I MHC interaction defined by charge reversal complementation and functional analysis

The molecular interactions between the CD8 co-receptor dependent N15 and N26 T cell receptors (TCRs) and their common ligand, the vesicular stomatitis virus octapeptide (VSV8) bound to H-2Kb, were studied to define the docking orientation(s) of MHC class I restricted TCRs during immune recognition. Guided by the molecular surfaces of the crystallographically defined peptide/MHC and modeled TCRs, a series of mutations in exposed residues likely contacting the TCR ligand were analyzed for their ability to alter peptide-triggered IL-2 production in T cell transfectants. Critical residues which diminished antigen recognition by 1000 to 10,000-fold in molar terms were identified in both N15 Valpha (alphaE94A or alphaE94R, Y98A and K99) and Vbeta (betaR96A, betaW97A and betaD99A) CDR3 loops. Mutational analysis indicated that the Rp1 residue of VSV8 is critical for antigen recognition of N15 TCR, but R62 of H-2Kb is less critical. More importantly, the alphaE94R mutant could be fully complemented by a reciprocal charge reversal at Kb R62 (R62E). This result suggests a direct interaction between N15 TCR Valpha E94R and Kb R62E residues. As Rp1 of VSV8 is adjacent to R62 in the VSV8/Kb complex and essential for T cell activation, this orientation implies that the N15 Valpha CDR3 loop interacts with the N-terminal residues of VSV8 with the Valpha domain docking to the Kb alpha2 helix while the N15 Vbeta CDR3 loop interacts with the more C-terminal peptide residues and the Vbeta domain overlies the Kb alpha1 helix. An equivalent orientation is suggested for N26, a second VSV8/Kb specific TCR. Given that genetic analysis of two different class II MHC-restricted TCRs and two crystallographic studies of class I restricted TCRs offers a similar overall orientation of V domains relative to alpha-helices, these data raise the possibility of a common docking mode between TCRs and their ligands regardless of MHC restriction.

Efficient beam-propagation method based on Padé approximants in the propagation direction

We propose a novel beam-propagation method (BPM) based on the higher-order Padé approximants in both the transverse and the longitudinal directions. Extending the Padé approximation to the propagation direction and adopting the multistep method increase the programming effort by only a small amount. Compared with the conventional BPM's, this method is more accurate and efficient. The accuracy and the propagation step size are well predicted by a phase analysis.

Regiospecificity of peroxyl radical addition to (E)-retinoic acid

The regiochemistry of peroxyl radical addition to (E)-retinoic acid (RA) was investigated. Peroxyl radicals, generated by reaction of 13-hydroperoxy-(9Z,11E)-octadecadienoic acid with hydroxo(porphyrinato)iron(III) in Tween 20 micelles, were reacted with RA. The major, and virtually exclusive, RA oxidation product was 5,6-epoxy-RA which was identified on the basis of cochromatography with the synthetic synthetic oxirane (in a reverse phase HPLC system), electronic absorption spectroscopy, high-field 1H-NMR, and EI mass spectrometry. These results suggest that peroxyl radicals react with RA by regioselective addition to either C5 or C6 yielding an endocyclic tertiary allylic or tertiary carbon-centered radical adduct, respectively. Subsequent beta-elimination of an alkoxyl radical yields the oxirane. Computational studies were carried out in order to gain mechanistic insights into the observed regiospecificity of the peroxyl radical-dependent epoxidation reaction; molecular mechanics and semiempirical quantum mechanical calculations were carried out using Tripos force field parameters and AM1, respectively. The results suggest that the regiospecific epoxidation may be influenced by the 5,6-olefinic function behaving as a partially-isolated double bond as well as inherent allylic A1,2 strain in the substituted cyclohexene ring as a consequence of substitutions at C1 and C6. In addition, calculated heats of formation indicated preferential peroxyl radical addition to C5 versus C6; this may reflect differences in the geometries of sp2-orbitals containing the radical densities rather than resonance contributions by the highly conjugated polyene system.

Heat stress induces tyrosine phosphorylation/activation of kinase FA/GSK-3 alpha (a human carcinoma dedifferentiation modulator) in A431 cells

Exposure of A431 cells to a rapid temperature increase from 37 degrees to 46 degrees C could induce an increased expression (approximately 200% of control) and tyrosine phosphorylation/activation (approximately 300% of control) of protein kinase FA/ glycogen synthase kinase-3 alpha (kinase FA/GSK-3 alpha) in a time-dependent manner, as demonstrated by an anti-kinase FA/GSK-3 alpha immunoprecipitate kinase assay and by immunoblotting analysis with anti-kinase FA/GSK-3 alpha and anti-phosphotyrosine antibodies. The heat induction on the increased expression of kinase FA/GSK-3 alpha could be blocked by actinomycin D but not by genistein. In contrast, the heat induction on tyrosine phosphorylation/activation of kinase FA/GSK-3 alpha could be blocked by genistein or protein tyrosine phosphatase, indicating that heat stress induces a dual control mechanism, namely, protein expression and subsequent tyrosine phosphorylation to cause cellular activation of kinase FA/GSK-3 alpha. Taken together, the results provide initial evidence that kinase FA/GSK-3 alpha represents a newly described heat stress-inducible protein subjected to tyrosine phosphorylation/activation, representing a new mode of signal transduction for the regulation of this human carcinoma dedifferentiation modulator and a new mode of heat induction on cascade activation of a protein kinase.

Reflux esophagitis after proximal subtotal gastrectomy

BACKGROUND

Carcinoma of the cardia of stomach or carcinoma of the esophagocardiac (EC) junction has a poor prognosis. Proximal subtotal gastrectomy is often performed for a smaller tumor. It achieves a prognosis similar to that of total gastrectomy and prevents pernicious anemia. A better functional result was expected than that total gastrectomy did from us, but the clinical observation was surprising. Most patients had symptoms of reflux esophagitis after surgery. All of these patients were reevaluated.

METHODS

From November, 1990 to March, 1996, there were 27 patients who received proximal subtotal gastrectomy at this hospital. Twenty of these were involved in this study. Floppy Nissen's fundoplication was performed during operation as a anti-reflux procedure. Continuous 24-h pH monitoring, esophageal manometry, and endoscopic examination were performed for study.

RESULTS

Most of the patients had symptoms of gastroesophageal reflux. 80% (16/20) of the patients were found to have reflux esophagitis under endoscopy. The patients had higher pH scores (mean 85.8 +/- 45.6) than normal (< 17.5), lower pressure of LES (8.03 +/- 7.01 mmHg), shorter total lengths (mean 1.60 +/- 0.56 cm) and intraabdominal lengths (mean 1.29 +/- 0.30 cm) of new lower esophageal sphincters.

CONCLUSIONS

Clearly there was failure to prevent reflux esophagitis through floppy Nissen's fundoplication. Severe gastroesophageal reflux did appear after proximal gastric resection. A gastric remnant with safe cut-margin is often too short to perform complete wrapping. Proximal subtotal gastrectomy is not recommended for early cancer of the cardia of the stomach.

Clinical experience of HIV/AIDS in a municipal hospital in Taiwan

To describe the spectrum of epidemiological and major clinical manifestations of patients infected by human immunodeficiency virus type 1 (HIV-1) in a municipal hospital, a retrospective review was done of 53 HIV-1-infected patients who had been admitted to Taipei Municipal Jen-Ai Hospital between January 1990, and July 1996. The majority (94.3%) of the patients in the cohort were male. Peak incidence was found in the fourth decade (28.3%). Forty-four (83%) patients presented in the first hospital stay with acquired immunodeficiency syndrome (AIDS). The mean duration between establishment of diagnosis of HIV-1 infection and that of AIDS was 11.2 (0-84) months. Heterosexual transmission accounted for 54.7% of the infections in the study group, and bi-/homosexual men made up another 32%. Psychosis of new onset was noted in two patients. In all AIDS indicator conditions, Pneumocystis carinii pneumonia (PCP) was the leading opportunistic infection among AIDS patients. PCP was also on the top of initial manifestations of HIV-1 infection. One patient with Penicillium marneffei infection was diagnosed to have AIDS. The mean CD4 count at admission of AIDS patients was much lower than that of non-AIDS patients (32 vs. 297/microliter, p < 0.0005). During the follow-up period 24 of 53 patients died. Mean survival time of 23 expired patients after establishment of diagnosis of AIDS was 6.4 (0-29) months. The results indicated that males outnumbered females greatly in the number of cases. Sexual activity remained the most important route of infection. Psychosis of new onset may be an early manifestation of HIV-associated encephalopathy and requires more attention. In addition, the outcome was poor as most patients in this area did not become aware of risk of HIV-1 infection until they were seriously illed with full-blown AIDS that they would seek medical help. PCP was the most common incentive for medical consultation. Penicillium marneffei infection is endemic in southeast Asia, and should be classified as an AIDS indicator condition in Taiwan.

14-3-3 epsilon positively regulates Ras-mediated signaling in Drosophila

We have isolated mutations in the gene encoding a Drosophila 14-3-3 epsilon protein as suppressors of the rough eye phenotype caused by the ectopic expression of RAS1(V12). Using a simple loss-of-function 14-3-3 epsilon mutation, we show that 14-3-3 epsilon acts to increase the efficiency of RAS1 signaling. The 14-3-3 epsilon protein appears to function in multiple RTK pathways, suggesting that it is a general component of RAS1 signaling cascade. Sequence analysis of three dominant-negative alleles defines two regions of 14-3-3 epsilon that participate in RAS1 signaling. We also present evidence that 14-3-3 epsilon and 14-3-3 zeta, two 14-3-3 protein family members, are partially redundant for RAS1 signaling in photoreceptor formation and in animal viability. Our genetic data suggest that 14-3-3 epsilon functions downstream of or parallel to RAF, but upstream of nuclear factors in RAS1 signaling.