Development of resistance and cross-resistance in Pseudomonas aeruginosa exposed to subinhibitory antibiotic concentrations

The purpose of this study was to compare resistance and cross-resistance development in Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients to commonly used antipseudomonal antibiotics. Isolates were repeatedly exposed to subinhibitory concentrations of either azlocillin, tobramycin, ceftazidime or ciprofloxacin. On 10 consecutive occasions, samples were removed from the half-MIC well of a microtitre plate and regrown in drug-free medium to provide the next inoculum for MIC determination. The increase in MIC at the end of the treatment period was significant (p<0.05) for all selecting antibiotics. Cross-resistance to unrelated antibiotics was not observed, but was significant (p<0.05) in all beta-lactams (ticarcillin, piperacillin, ceftazidime and cefsulodin) studied where azlocillin was the selecting antibiotic. The addition of clavulanic acid to ticarcillin and of tazobactam to piperacillin had no effect on cross-resistance. The development of resistance to azlocillin was associated with increased beta-lactamase activity and a change in isoelectric point of the beta-lactamases. The result of this study supports a rotational policy for antipseudomonal antibiotics in CF patients.

The anesthetic management of a preterm infant weighing 500 grams undergoing ligation of patent ductus arteriosus--a case report

PDA (patent ductus arteriosus) is a common congenital heart disease. Usually surgical intervention through left thoracotomy or recently through video assisted thoracoscopy will be recommended if the preceding or intent medical treatment fails or is contraindicated. However, once surgical intervention is decided, various complications are still a real fear in the mind of the surgeon and the anesthesiologist, particularly if the infant is premature or very sick. Here we report an anesthetic management in a female preterm infant weighing 500 grams, who underwent PDA ligation. She was born at gestation age of 28 weeks at our hospital, and since her birth she was noted to have infant respiratory distress syndrome associated with renal dysfunction. She was admitted to the neonatal intensive care unit (NICU) straightaway. After thorough examination, a severe PDA was disclosed. The possibility of pulmonary hemorrhage and heart failure could be predicted in view of the large left to right shunt. Worst of all was that her poor renal function contradicted a medical treatment. So we decided to carry out the ligation procedure at once although she was premature and only 5 days old. The NICU was chosen as the operation theater for transferring concerns. General anesthesia was induced and maintained by atropine 0.01 mg, pancuronium 0.1 mg, fentanyl 2 micrograms, and ketamine 0.15 mg intravenously. Supplemental oxygen was given throughout the operation. The PDA was ligated through left thoracotomy and blood loss was minimal. The peri-operative course was uneventful. The patient recovered well following surgery and anesthesia.

Adult type anomalous origin of the left coronary artery from the main pulmonary artery: report of one case

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA syndrome) is a rare disease. Most of the cases suffer from myocardial infarction, congestive heart failure or even death during the early infantile period, and thus are called "infantile type". We present one five-year-old girl with ALCAPA syndrome, adult type, who was initially suspected to be a case of atypical Kawasaki disease (KD) complicated with coronary arterial aneurysms. Due to persistent dilatation of the coronary artery after medical treatment for one year and a turbulent flow noticed between the left coronary artery (LCA) and the main pulmonary artery (MPA), cardiac catheterization was arranged. The diagnosis was established from the coronary cineangiography in spite of a direct connection between the aorta and LCA revealed from the echocardiogram. Thereafter open heart surgery was undertaken. Diagnosis of ALCAPA syndrome can be made by echocardiogram, but this is not fully satisfactory. Selective coronary cineangiography remains the definitive diagnosis. Although the patients of adult type are more asymptomatic, surgical correction should be undertaken as soon as the diagnosis is established since a substantial risk is still present.

Abnormal transcripts of FHIT gene in Chinese brain tumors

FHIT located at chromosome 3p14.2 was discovered and proposed as a candidate tumor suppressor gene in several cancers. To determine whether the FHIT gene at 3p14.2 is altered in Chinese brain tumors, we examined 13 brain tumors for deletions within FHIT locus. Evaluation of the FHIT gene in the panel of brain tumors led to a comprehensive mutation analysis. The complete sequence of the FHIT gene was determined and deletions between exon 5-8 were found in all 13 cases. In addition, single point mutation of amino acid from two glioblastoma and one atypical meningioma cases and multiple amino acid mutations from one pituitary tumor were observed. Our results support the hypothesis that FHIT gene alteration is involved in tumorigenic development of human neoplasms.

Total synthesis of (-)-incrustoporin

(-)-Incrustoporin (1) has been synthesized using aldol condensation of ethyl p-tolyl-acetate (2) and (2R)-benzoyloxy-butanal (3), followed by acid-catalyzed deprotection of the benzoyl group, lactone ring-closure, and elimination of the beta-OH in a one-pot manner. The aldehyde 3 was prepared from the commercially available D-mannitol by a two-directional strategy.

[Protection of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E) on experimental ulcers in rats]

The effects of dl-(15R)-15 methyl-PGE2 methyl ester (PG6E), in experimental ulcers induced by absolute alcohol, HCl, indomethacin, pyloric ligation and chronic acetic acid in rats were studied. PG6E at doses 10-80 micrograms.kg-1 was shown to have significant protective effect. PG6E (30-60 micrograms.kg-1) was also found to reduce markedly the acid secretion, pepsin activity, DNA content of the juice collected from pylorus ligated stomach of rats and increase markedly the content of gastric mucosa hexosamine in mice given PG6E (30-60 micrograms.kg-1 po for 3 d). At doses of 40-80 micrograms.kg-1, PG6E was able to have no significant effect on gastric emptying time in rats and gastrointestinal tract movement in mice. It appears that PG6E was shown to inhibit the aggressive factors and increase the protective factors of gastric mucosa. This may hopefully become a new antiulcer agent.

Carboxyl terminal of rhodopsin kinase is required for the phosphorylation of photo-activated rhodopsin

Human rhodopsin kinase (RK) and a carboxyl terminus-truncated mutant RK lacking the last 59 amino acids (RKC) were expressed in human embryonic kidney 293 cells to investigate the role of the carboxyl terminus of RK in recognition and phosphorylation of rhodopsin. RKC, like the wild-type RK, was detected in both plasma membranes and cytosolic fractions. The C-terminal truncated rhodopsin kinase was unable to phosphorylate photo-activated rhodopsin, but possesses kinase activity similar to the wild-type RK in phosphorylation of small peptide substrate. It suggests that the truncation did not disturb the gross structures of RK catalytic domain. Our results also show that RKC failed to translocate to photo-activated rod out segments. Taken together, our study demonstrate the carboxyl terminus of RK is required for phosphorylation of photo-activated rhodopsin and strongly indicate that carboxyl-terminus of RK may be involved in interaction with photo-activated rhodopsin.

[The density and larval habitats of dengue vectors in Chungho city]

A survey was conducted to understand larval habitats and density of dengue vectors in Chungho city during the period of August 12 to September 13, 1996. Most villages (41 in the total of 93) were found to have the density figures of three for Aedes albopictus Skuse. The second common density figures were found at 2nd and 4th levels. The most common breeding containers found were less than 5 cm in water depth and less than 100 cm2 in water area. The number of breeding containers reduced when the water depth and size increased. The common breeding containers in villages were flower vases (30%) and water buckets (18%). In the mountains, water buckets (34%) and kitchen tools (11%) were common. In parks, water buckets (29%) and tires (15%) were commonly found. In cemeteries, the common breeding containers were flower vases (57%) and earthenware pots (17%). The average (2.05 containers per man-hour) of positive water containers in the mountains was significantly higher than that in parks (0.62). However, the average in cemeteries (1.29) was not significantly different from those collected in mountains and parks.

Pertussis toxin-insensitive signaling of the ORL1 receptor: coupling to Gz and G16 proteins

Nociceptin/OFQ is the endogenous ligand for the G protein-coupled opioid receptor-like (ORL1) receptor. To elucidate the cellular functions of the ORL1 receptor, we examined its ability to interact with Gz and G16, two pertussis toxin (PTX)-insensitive G proteins that are known molecular partners for the opioid receptors. In HEK 293 cells transiently expressing the ORL1 and dopamine D1 receptors, nociceptin/OFQ dose-dependently inhibited dopamine-stimulated cyclic AMP (cAMP) accumulation in a PTX-sensitive manner. However, PTX failed to block the nociceptin/OFQ-induced inhibition of dopamine-stimulated cAMP accumulation in HEK 293 cells co-expressing the alpha-subunit of Gz. This result indicates functional interaction between the ORL1 receptor and Gz. A similar result was obtained with retinoic acid-differentiated SH-SY5Y cells, which endogenously express both the ORL1 receptor and Gz. When the ORL1 receptor was transiently co-expressed in COS-7 cells with the alpha-subunit of G16, nociceptin/OFQ dose-dependently stimulated the formation of inositol phosphates. Nociceptin-induced stimulation of phospholipase C was absolutely dependent on the co-expression of alpha16 and exhibited the appropriate ligand selectivity. In terms of its ability to interact with PTX-insensitive G proteins, the ORL1 receptor behaves very much like the opioid receptors.

Chemokine receptor CCR5 functionally couples to inhibitory G proteins and undergoes desensitization

Chemokine receptor CCR5 is not only essential for chemotaxis of leukocytes but also has been shown to be a key coreceptor for HIV-1 infection. In the present study, hemagglutinin epitope-tagged human CCR5 receptor was stably expressed in Chinese hamster ovary cells or transiently expressed in NG108-15 cells to investigate CCR5-mediated signaling events. The surface expression of CCR5 was confirmed by flow cytometry analysis. The CCR5 agonist RANTES stimulated [35S]GTPgammaS binding to the cell membranes and induced inhibition on adenylyl cyclase activity in cells expressing CCR5. The effects of RANTES were CCR5 dependent and could be blocked by pertussis toxin. Furthermore, overexpression of Gialpha2 strongly increased both RANTES-dependent G-protein activation and inhibition on adenylyl cyclase in cells cotransfected with CCR5. These data demonstrated directly that activation of CCR5 stimulated membrane-associated inhibitory G proteins and indicated that CCR5 could functionally couple to G-protein subtype Gialpha2. The abilities of CCR5 to activate G protein and to inhibit cellular cAMP accumulation were significantly diminished after a brief prechallenge with RANTES, showing rapid desensitization of the receptor-mediated responsiveness. Prolonged exposure of the cells to RANTES caused significant reduction of surface CCR5 as measured by flow cytometry, indicative of agonist-dependent receptor internalization. Our data thus demonstrated that CCR5 functionally couples to membrane-associated inhibitory G proteins and undergoes agonist-dependent desensitization and internalization.

Stimulation of hepatocyte growth factor production by ascorbic acid and its stable 2-glucoside

Hepatocyte growth factor (HGF), a cytokine which is generally produced by mesenchymal cells, has mitogenic, motogenic and morphogenic activities in epithelial cells and it also has tumor-suppressing activities. Induction of HGF production may be involved in organ regeneration, wound healing and embryogenesis. We examined the effects of ascorbic acid (AsA), which stimulates the proliferation of fibroblasts, and its stable derivative, 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G), on HGF production by human skin fibroblasts. Basal HGF secretion was significantly stimulated by more than 0.1 mM AsA or AA-2G. Both vitamins synergistically enhanced HGF secretion stimulated by growth factors such as epidermal growth factor (EGF), platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF), cholera toxin and other inducers. Induction by EGF or bFGF was most markedly potentiated by the vitamins. HGF production by the KG-1 human leukemia cell line was also augmented by AsA or AA-2G. Another stable AsA derivative, ascorbic acid 2-phosphate (AA-2P) effectively promoted basal and EGF-induced HGF secretion by the fibroblasts, but ascorbic acid 2-sulfate (AA-2S) was much less effective. Intracellular AsA levels increased after the addition of AA-2G and AA-2P as well as AsA, but not after AA-2S. The effect of AA-2G was completely abrogated by the simultaneous addition of castanospermine, an alpha-glucosidase inhibitor, suggesting that the active form of AA-2G is AsA. Constitutive and EGF-induced HGF gene expression was also up-regulated after adding AsA or AA-2G to the cells. These results indicated that AsA acts alone or in synergy with several inducers to stimulate the production and gene expression of HGF in human skin fibroblasts and that the stable AsA derivative AA-2G is as effective as AsA in promoting HGF production.

Selective interference of beta-arrestin 1 with kappa and delta but not mu opioid receptor/G protein coupling

The role of beta-arrestin 1 (beta-arr1) in regulation of responsiveness of kappa, delta, and mu opioid receptors has been investigated in human embryonic kidney 293 cells cotransfected with opioid receptor and beta-arr1. Expression of human beta-arr1 attenuated kappa and delta opioid receptor subtype-mediated inhibition of cAMP production and resulted in a 100-fold increase of EC50 values for kappa-agonist U69593 and delta-agonist [D-Pen2, D-Pen5]enkephalin and 30-40% reduction of their maximal responses. In contrast, coexpression of beta-arr1 with mu opioid receptor did not affect the concentration-effect relationship of mu-agonist [D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin. In parallel, kappa and delta receptor-mediated G protein activation was also remarkably attenuated by overexpression of beta-arr1, while the mu-agonist-stimulated response remained intact. These results indicate that beta-arr1 interferes receptor/G protein coupling and differentially regulates the responsiveness of opioid receptors. Truncation of kappa and delta opioid receptors at carboxyl termini abolished inhibition of beta-arr1 on the responsiveness of both receptors. Furthermore, mu opioid receptor became sensitive to beta-arr1 regulation following replacement of its carboxyl terminus with the corresponding portion of the delta receptor. Removal of potential phosphorylation sites on the carboxyl terminus of kappa opioid receptor led to reduced effect of beta-arr1 on the receptor-mediated response. These results suggest that receptor carboxyl terminus and its phosphorylation play an important role in the interaction of beta-arr1 and opioid receptors.

Failure to activate cytosolic phospholipase A2 causes TNF resistance in human leukemic cells

Activation of cytosolic phospholipase A2 (cPLA2) by TNF has been shown to be an important component of the signaling pathway leading to cell death. The role of cPLA2 in the cytotoxic action of TNF was investigated in a panel of human leukemic cell lines. TNF could activate cPLA2 only in U937 and HL60 TNF-sensitive leukemic cells, but not in KG1a, CEM, and CEM/VLB100 cells that are relatively resistant to TNF. Pretreatment with 4-bromophenacyl bromide, a cPLA2 inhibitor, rendered U937 and HL60 cell lines resistant to the cytotoxic effect of TNF. Immunoblot and reverse-transcriptase PCR demonstrated that cPLA2 expression was detectable at both transcriptional and translational levels in all leukemic cell lines studied, although CEM and CEM/VLB100 cells expressed cPLA2 mRNA and protein at lower levels. The protein synthesis inhibitor, cycloheximide, increased TNF-induced cPLA2 activity and cytotoxicity in both CEM and CEM/VLB100 cell lines. Low levels of cPLA2 activity in the KG1a cell line could be activated by the cPLA2 activator mellitin, or the calcium ionophore A23187. The data suggest that cPLA2 activity is involved in TNF-induced cytotoxicity in leukemic cells. Resistance to TNF-induced cytotoxicity may involve either protein inhibitors that act upstream of cPLA2 in the TNF-signaling pathway or constitutive defects of cPLA2 itself, possibly involving calcium utilization.

cDNA sequence and expression of the mouse alpha1(V) collagen gene (Col5a1)

Several overlapping cDNA clones corresponding to the entire coding sequence of the mouse alpha1(V) collagen gene (Col5a1) were isolated. The conceptual amino acid translation indicated a high degree of sequence identity (94%) with the human alpha1(V) chain. All of the important structures previously noted in the human alpha1(V) chain were also conserved in the mouse chain. The alpha1(V) transcripts were easily detected in mouse embryos as early as 11 days post coitum (d.p.c.). The transcripts were widely distributed in non-cartilaginous and cartilaginous tissues. Finally, we calculated the ratio of transcripts of alpha1(V):alpha2(V):alpha1(XI) in the calvaria and tongue of 18 d.p.c. embryos using the competitive reverse transcription-polymerase chain reaction (RT-PCR) technique. The results raised the possibility that there are at least two different kind of types V/XI collagen heterotrimers in mouse embryonic tissues.

N-Methyl-D-aspartate attenuates opioid receptor-mediated G protein activation and this process involves protein kinase C

The effects of N-methyl-D-aspartate (NMDA) on opioid receptor-mediated G protein activation were explored in neuroblastoma X glioma hybrid (NG108-15) cells. Treatment of the cells with NMDA resulted in a remarkable attenuation of [35S]guanosine-5'-O-(3-thio)triphosphate binding stimulated by [D-Pen2,D-Pen5]-enkephalin (DPDPE), a delta-opioid receptor agonist. The effects of NMDA were dose and time dependent with an IC50 value of 5 nM and could be blocked by NMDA receptor antagonists. After NMDA treatment, the DPDPE dose-response curve shifted to the right (EC50 value increased approximately 7-fold, from 6 to 40 nM), and the maximal response induced by DPDPE was reduced by approximately 60%. The effects of NMDA were reversible, and the DPDPE response could recover within 60 min. The functional responses of delta-, mu-, and kappa-opioid receptors in primarily cultured neurons also were attenuated significantly by NMDA treatment. The inhibitory effects of NMDA on opioid receptor-mediated G protein activation could be blocked by coadministration of the protein kinase C (PKC) inhibitors or by elimination of the extracellular Ca2+. Correspondingly, NMDA treatment of NG108 cells significantly elevated cellular PKC activity and stimulated Gialpha2 phosphorylation. Transient transfection into NG108-15 cells of the wild-type Gialpha2 and a mutated Gialpha2 (Ser144Ala) resulted in a 2-fold increase in DPDPE-stimulated G protein activation. The DPDPE responses were greatly inhibited by NMDA treatment in the wild-type Gialpha2-transfected cells but much less affected in the mutant Gialpha2-transfected cells. In summary, NMDA attenuates opioid receptor/G protein coupling, and this process requires activation of PKC.

1,25-Dihydroxyvitamin D3 protects human leukemic cells from tumor necrosis factor-induced apoptosis via inactivation of cytosolic phospholipase A2

The mechanism by which tumor necrosis factor (TNF) induces death of cancer cells appears to involve the activation of cytosolic phospholipase A2 (cPLA2). U937 human leukemic cells treated with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3; 10(-8) M] become resistant to TNF, an effect that is independent of cell cycle status and expression of TNF receptors or BCL-2. In this study, TNF produced a dose- and time-dependent enhancement of [3H]arachidonic acid release in U937 cells. The amount of [3H]arachidonic acid release was positively associated with TNF-induced apoptosis. Both immunofluorescence microscopy and Western blotting of cell subcompartments demonstrated translocation of cPLA2 from the cytosol to the cell membrane in response to TNF. In addition, TNF up-regulated expression of cPLA2 mRNA. An antisense oligonucleotide to cPLA2 and the cPLA2 inhibitor 4-bromophenacyl bromide significantly inhibited TNF-induced cytotoxicity. Prior incubation of cells with 1,25(OH)2D3 significantly inhibited (a) TNF-induced [3H]arachidonic acid release and apoptosis, (b) TNF-induced translocation of cPLA2 to the membrane, and (c) the up-regulation of cPLA2 mRNA with TNF. Furthermore, the inhibitory effect of 1,25(OH)2D3 was not reversed by inhibitors of transcription or translation. The data suggest that activation of cPLA2 is involved in TNF-induced apoptosis of leukemic cells. 1,25(OH)2D3 directly inhibits cPLA2 translocation and mRNA up-regulation induced by TNF. Disruption of cPLA2 activation may represent a possible mechanism whereby leukemic cells can become resistant to TNF-mediated killing.

Inhibition of phospholipase C blocks opioid receptor-mediated activation of Gi proteins

Activation of phospholipase C (PLC) in response to stimulation of delta-opioid, m4 muscarinic and alpha2 adrenergic receptors was observed in NG108-15 cells. Treatment with PLC specific inhibitors, U73122 and ET-18-OCH3, blocked delta-opioid receptor-mediated activation of G proteins with no effect on opioid binding to the receptors. U73122 treatment also suppressed functional responses of m4 muscarinic and alpha2 adrenergic receptors in NG108-15 cells. Furthermore, the G protein activation mediated by mu- and delta-opioid receptors and opioid receptor-like receptor (ORL1) were abolished by U73122 in SK-N-SH neuroblastoma cells. Inhibition of adenylyl cyclase induced by high concentrations of GTP was blocked by U73122, suggesting that blockade is at the level of G proteins. Our results thus indicated that inhibition of PLC leads to blockade of Gi protein activation mediated by opioid receptors or other Gi-coupled receptors.

How Chinese scientists discovered qinghaosu (artemisinin) and developed its derivatives? What are the future perspectives?

Since the middle of this century and especially since the 1960s and 1970s. Chinese scientists have put considerable effort and resources into the search for new antimalarial compounds extracted from Chinese traditional herbs. Archaeological findings indicate that qinghao (Artemisia annua L.) has been used as a traditional remedy in China for over two thousand years. Its antimalarial principle was finally isolated in 1971 and named artemisinin or qinghaosu (meaning the principle of qinghao in Chinese). Its rapid action, low toxicity and powerful effect against falciparum malaria made it a favored subject for research. In 1976, the unique structure of the molecule, characterized by an endoperoxide and an alternative O-C-O-C segment, was identified. The specific lactone reduction discovered during the determination of the structure opened the way for the synthesis of qinghaosu derivatives, and thereafter a series of more active and more oil- or water-soluble derivatives was developed. Subsequent studies of the structure/activity relationship led to the discovery of dihydroartemisinin, artemether and artesunate. Now qinghaosu and these three derivatives are being used around the world as effective new antimalarial drugs in the fight against falciparum malaria, including multi-drug-resistant Plasmodium falciparum. At the present time new qinghaosu analogues or derivatives are being developed and studies of their structure/activity relationships, their antimalarial mechanisms, their interaction with ferrous ions and the DNA damage associated with these processes are being actively pursued. In addition, recent studies also indicate that some qinghaosu derivatives have other bioactivities, including antiparasitic (against Schistosoma japonicum, Toxoplasma gondii and so on) and anticancer activities. Research into qinghaosu and its derivatives has already produced and will no doubt continue to produce results of the utmost importance in the fight against malaria and other diseases.

Abnormal transcripts of FHIT gene in thyroid cancer

Abnormalities of the FHIT gene were found in many carcinoma cell lines and human tumors as reported which suggest an etiological function in tumorigenesis. To investigate whether the FHIT gene is a target of thyroid tumor specific 3p alterations, we screened the FHIT gene for alteration in thyroid tumors and found that the tumors exhibited aberrant FHIT gene expression. The complete sequence of the FHIT gene in seven cases was determined and deletions between exon 2-9 in different regions were found. Goiter samples as control had normal FHIT transcripts while both normal and aberrant transcripts of FHIT were found not only in the tumor samples but also in the adjacent non-tumorous portion of the thyroid tumor. Our results support the hypothesis that FHIT gene alteration is involved in tumorigenetic development of human neoplasms in thyroid glands.

Functional expression of opioid receptor-like receptor and its endogenous specific agonist nociceptin/orphanin FQ during mouse embryogenesis

Expression of opioid receptor-like receptor (ORL1) and its endogenous peptide agonist nociceptin/orphanin FQ (N/OFQ) during mouse embryogenesis have been investigated. Transcripts of ORL1 and N/OFQ were detected by RT-PCR in mouse brain of day 8 embryo (E8) and the expression continued afterwards. Northern blot analysis revealed abundant expression of ORL1 at postnatal day 1 (P1) and N/OFQ at E17 and P1 in the brain but none was detected in other embryonic tissues. The presence of functional ORL1 in mouse embryonic brain was also confirmed by specific binding of [3H] N/OFQ (kd = 1.3 +/- 0.5 nM and Bmax = 72 +/- 9 fmol/mg protein) as well as by N/OFQ-stimulated G protein activation.

Effect of aging on psychological stress-induced increases in noradrenaline release in the rat anterior hypothalamus: an in vivo microdialysis study

Basal and psychological stress-induced noradrenaline (NA) release were studied by intracerebral microdialysis in the hypothalamus of rats aged 9 weeks or 12 months. Basal NA output was not significantly different between young (9-week-old; 2.11 +/- 0.22 pg/20 min) and aged (12-month-old; 2.29 +/- 0.34 pg/20 min) rats. Psychological stress for 20 min significantly increased NA release in both groups (186% and 142% of baseline at 9 weeks old and 12 months old, respectively); however, the increase in aged rats was significantly lower than that in young rats (P < 0.01). This finding suggest that the noradrenergic neuronal response to psychological stress is attenuated in aged rats.

[A study on the metabolites of dl-3-n-butyphthalide in rats]

The metabolites of dl-3-n-butylphthalide(NBP), a novel drug with promising protective action against cerebral ischemia, was studied in rats. Two main in vitro metabolites of NBP, M I and M II, were isolated and purified from rat liver microsome incubating system by using HPLC. The structure elucidation was mainly accomplished by spectral studies(UV, 1H-NMR, MS). Within 24 h following i.g. 3H-NBP, the total radioactivity excreted in urine and feces was 73.7% of the dose. Comparing with previous study, within 72 h following i.g. NBP, the total prototype drug excreted in urine and feces was 2.53% of the dose. This result excludes the possibility that NBP accumulates in vivo. The urine and brain homogenate of the rats(i.g. 3H-NBP) were analyzed by TLC. M I and M II were found in urine and M I was found in brain only. Furthermore, the ratio of radioactive M I to proptype drug was 1:1 in rat brain within 1 h following i.g. 3H-NBP. So, M I and M II were supposed to be the two main in vivo metabolites of NBP and M I might be an active metabolite.

Retardation of pain development: a case of recovery from congenital insensitivity to pain

Congenital analgesia is a rare genetic disorder. We report here that a 12-year-old boy was able to recover from congenital insensitivity to pain. Neurological examinations revealed that there was a 'stocking' distribution of pain decrement on the lower extremities under the patient's knee joints. Magnetic Resonance Imaging (MRI) of his brain showed gyrus thinning with sulcus widening at both sides of the parietal lobe. Southern blot hybridization probed with cDNAs of various opioid receptors did not detect any significant abnormality. Our results suggest that this rare case may not be genetically determined.

[Clinical study on tongxinluo capsule in treatment of patients with angina pectoris caused by coronary heart disease]

OBJECTIVE

To observe the effects of Tongxinluo capsule (TXLC) in treating angina pectoris (AP) caused by coronary heart disease (CHD) and evaluate its safety.

METHODS

Randomized single-blind controlled design were adopted. Three hundred and forty two patients were treated with TXLC (4 capsules, three times daily), and 150 patients in the control group done with Shuxin oral liquor (SXOL, 20 ml, two times daily). After 4 weeks of treatment, the data of AP, ECG, main symptoms, total effects were collected and evaluated.

RESULTS

TXLC appeared to be more effective than SXOL for patients with mild, moderate, severe AP (P < 0.01), except with mild stomach discomfort for a few patients, TXLC has no side effect and toxicity.

CONCLUSION

TXLC is an effective drug in treating AP and has no side effects and toxicity.

Molecular characterization and functional expression of opioid receptor-like1 receptor

The opioid receptor-like1 receptor (ORL1), an orphan receptor whose human and murine complementary DNAs, has been characterized recently. ORL1 transcripts are particularly abundant in the central nervous system. We demonstrated that ORL1 expressed in human neuroblastoma SK-N-SH and SH-SY5Y cell lines by radioligand binding assay, reverse transcription polymerase chain reaction (RT-PCR) and Northern analysis in the present study. Stimulation with ORL1 specific agonist, nociceptin/orphanin FQ, increased [35S]GTP gamma S binding to SK-N-SH cell membranes (EC50 = 14 +/- 0.45 nM), and attenuated forskolin-stimulated accumulation of cellular cAMP (EC50 = 0.80 +/- 0.45 nM), indicative that activation of ORL1 activates G proteins and inhibits adenylyl cyclase. Activation of ORL1 receptor was also accessed using CHO:hORL1 cell line by microphysiometer. Treatment of nociceptin/orphanin FQ increased extracellular acidification rate significantly.

Endogenous opioid receptor-like receptor in human neuroblastoma SK-N-SH cells: activation of inhibitory G protein and homologous desensitization

Endogenous expression of opioid receptor-like receptor (ORL1), in human neuroblastoma SK-N-SH cells was demonstrated by binding with nociceptin/ orphanin FQ (N/OFQ). Scatchard analysis of [3H]N/ OFQ saturation binding data gave Kd = 1.3 +/- 0.1 nM and Bmax = 1.58 +/- 2.5 fmol/mg protein. N/OFQ stimulation increased [35S]GTP gamma S binding to cell membranes and attenuated forskolin-induced cAMP accumulation in a concentration-dependent manner. The effects of N/OFQ were eliminated by the pretreatment of pertussis toxin (PTX) but not by the antagonists of opioid receptors, revealing mediation of N/OFQ signal transduction by ORL1 receptor and PTX sensitive G protein(s). The ability of N/OFQ to inhibit cAMP production was greatly reduced after prechallenging with N/OFQ, indicating that ORL1 undergoes homologous desensitization in neuronal cells.

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.

Long-term survival after neonatal arterial switch operation

An arterial switch operation was used only for a hyperdynamic transposition of the great arteries beyond the neonatal period at this hospital until the end of 1989. A 20-day-old baby girl underwent an arterial switch operation on March 3 1992 under the impression of simple transposition of the great arteries. The coronary artery pattern was Shaher's type 4. An autologous aortic flap just above the facing commissure was used to augment the medially based trapdoor for the left circumflex scallop. The baby survived the operation and has been faring well for the past three years. This case is the longest survival after a neonatal arterial switch operation in our hospital.

A comparative study of the risk factors for lung cancer in Guangdong, China

A case-control study involving 390 lung cancer cases, matched 1:1 with controls, was carried out in Guangdong Province to compare risk factors for different histopathologic types of lung cancer in both sexes. Female and male lung cancers appear to differ in epidemiological characteristics, pathologic types, and risk factors. The 291 lung cancer cases in males were predominantly squamous cell lung carcinoma (squamous cell carcinoma/adenocarcinoma = 1:0.5), whereas the 99 female lung cancer cases were predominantly adenocarcinoma (squamous cell carcinoma/adenocarcinoma = 1:2.7). The age at which lung cancer was first diagnosed was lower for females than for males (P < 0.0001). Single-factor conditional logistic regression analysis showed an association of lung cancer with family history of tumors, family history of lung cancer, history of chronic bronchitis/emphysema, history of tuberculosis, history of other lung disease, smoking, exposure to environmental tobacco smoke (ETS) in the home and in the workplace, being professional drivers, use of oral contraceptives, and consumption of pickled and salted fish (P < 0.05). Further multivariate logistic regression analysis showed that family history of tuberculosis, history of chronic bronchitis/emphysema, family history of tumors, smoking, exposure to ETS in the home and in the workplace, and consumption of pickled and salted fish were independent risk factors for lung cancer. Using log-linear model analysis, it was confirmed that lung cancer had significant interactions with chronic bronchitis/emphysema, exposure to ETS, history of tuberculosis and smoking. Smoking, however, could only explain 1/5 of the incidence of female lung cancers. Family history of lung cancer and the use of oral contraceptives were related to lung cancer in women. Except for a weak relationship with history of chronic bronchitis/emphysema, adenocarcinoma was found to have no association with the other risk factors.

[Effect of integrated Chinese medicine on early stage of acute cerebral hemorrhage]

The effect of integrated Chinese medicine (ICM) on the convalescent of acute cerebral hemorrhage patients were observed. The results showd that the effect of patients treated with ICM was better than that treated with Western medicine alone on the aspects of absorption of brain hemetoma, elimination of encephaledema and recovery of neural function (P < 0.05, 0.01). It suggested that early application of integrated Chinese medicine is very helpful in rehabilitation of cerebral hemorrhage patients.

Modulation of surface TNF expression by human leukaemic cells alters their sensitivity to exogenous TNF

In this study, U937 leukaemic cells underwent apoptotic cell death following exposure to TNF. Pre-incubation of cells for 48 h with VitD(3) (10(-8)M) induced resistance to TNF, whereas incubation with tau-IFN or GM-CSF increased susceptibility to TNF. Resistance to exogenous TNF (exTNF) following culture with VitD(3) was associated with increased expression of endogenous TNF (enTNF). The TNF inhibitors pentoxifylline(PTF) and dichloroisocoumarin (DCI) inhibited TNF synthesis by U937 cells and abrogated the increase in resistance to TNF seen with VitD(3). The tau-IFN increased TNF expression, whereas GM-CSF had little effect. The data show that the sensitivity of leukaemic cells to exTNF can be modulated by cytokines. The protective effect of VitD(3) is mediated in part by directly upregulating enTNF synthesis.

[A case-control study on the risk factors of lung cancer in Guangdong]

A case-control study on interaction among the risk factors of primary lung cancer with 390 matched pairs was carried out in Guangdong from 1990 to 1993. The subjects of study were the in-patients with primary lung cancer (age 32-78), which consisted of 171 cases of primary lung squamous cell cancer (L. S), 138 cases of primary lung adenocarcinoma (L. A), and 81 cases of other pathological type (L. S:L. A = 1:0.8). Primary lung squamous cell cancer accounted for the majority (51.55%) of 291 male cases (L. S:L. A = 1:0.5). Primary lung adenocarcinoma made up the majority (57.57%) of 99 female cases (L. S:L. A = 1:2.7). Single factor conditional logistic regression analysis showed that the occurrence of lung cancer was closely associated with history of chronic bronchitis, emphysema, pulmonary tuberculosis and other pulmonary diseases (OR = 2.9-3.6, chi 2 = 13.52-37.55, P < 0.01) other risk factors were smoking, passive smoking from spouse or in the working place and family history of tumour (OR = 2.7-3.6, chi 2 = 8.53-33.15, P < 0.01). Driver, taking oral contraceptive, liking pickles or salted fish and bad ventilation in kitchen could be the risk factors of lung cancer (OR = 1.3-3.0, chi 2 = 4.78-5.0, P < 0.05). Further multiple conditional logistic regression analysis turned out that history of chronic bronchitis, emphysema, pulmonary tuberculosis, smoking, family history of tumour, passive smoking from spouse or in the working place, liking pickles were the independent risk factors of lung cancer (OR = 1.7-3.5). In search of the interaction between lung cancer and the risk factors which included history of chronic bronchitis, emphysema, pulmonary tuberculosis, smoking and passive smoking, a loglinear model analysis was performed. The results revealed that there was significant interaction between two factors in one-stage analysis. Although the interaction existed between chronic bronchitis and tuberculosis, chronic bronchitis and smoking or passive smoking, tuberculosis and passive smoking in the meantime, it had not attained the level of significance among three or more factors (including the principal effect of lung cancer) in two-stage analysis (chi 2 = 1.31-2.27, P > 0.13), and therefore the interaction of the former was not affected by the effects of the latter as yet.

Circumvention of P-glycoprotein-mediated drug resistance in human leukaemic cells by non-immunosuppressive cyclosporin D analogue, SDZ PSC 833

Cyclosporin A (CSA) exhibits greater multidrug resistance (MDR) modulating activity in vitro than other MDR modulators such as verapamil and quinidine. However, the immunosuppressive and nephrotoxic effects of CSA may limit its clinical use. PSC 833, a new cyclosporin D derivative, exerts a higher MDR reversal activity but lacks toxic or immunosuppressive effects. The drug-resistant sublines K/DAU100, K/DAU200, K/DAU300, K/DAU400, K/DAU500 and K/DAU600 have been derived from the drug-sensitive parental cell line, K562 cl.6 and CEM/VLB100 is a drug-resistant derivative of CCRF-CEM. We report a comparison of the effects of PSC 833 and CSA on daunorubicin (DAU) transport kinetics and chemosensitivity in these cell lines. Both CEM/VBL100 and K562 cl.6 DAU-resistant cells displayed high levels of P-glycoprotein (PGP), decreased DAU accumulation and increased DAU efflux when compared to their parental cells. PSC 833 was 1.6-, 3.4-, 4.9- and 4.6-fold more effective than CSA in reversing DAU resistance in higher resistance CEM/VLB100, K/DAU400, K/DAU500 and K/DAU600 cells respectively. DAU transport kinetics showed that PSC 833 was more effective than CSA in increasing cellular DAU accumulation and decreasing DAU efflux in higher resistant leukaemia subclones. PSC 833 could restore DAU retention at lower doses and was more active than CSA in all the resistant cells. A 89-100% restoration of intracellular DAU retention were gained by PSC 833 at 1.0 microM in K562 cl.6 DAU-resistant sublines, whereas a 73-100% restoration of DAU retention was obtained by CSA only at 30.0 microM in the same resistant sublines. PSC 833 at 3.0 microM is sufficient to restore full DAU retention in all resistant cells. CSA, however, even at 30.0 microM, cannot confer full restoration of DAU retention in higher resistance K562 cl.6/DAU sublines. By measuring MDR modulator-mediated short-term inhibition of PGP function, PSC 833 was found to be at least 10-30 times more active than CSA. As no effect on DAU retention and sensitivity has been found in sensitive parental cells with PSC 833, it is suggested that PSC 833 may act by blocking the effluxing function of PGP in the resistant leukaemia cells.

TNF-mediated killing of human leukaemic cells: effects of endogenous antioxidant levels and TNF alpha expression in leukaemic cell lines

Using the human erythroleukaemic cell line K562 cl.6 and its daunorubicin-resistant subline K/DAU600, and the human T-lymphoblastic leukaemic cell line CCRF-CEM and its vinblastine-resistant subline CEM/VLB100, we have shown that the drug-resistant cell lines were more sensitive to cytotoxicity induced by tumour necrosis factor-alpha (TNF alpha). Drug-resistant cell lines showed increased activities of copper/zinc superoxide dismutase (Cu/ZnSOD) and catalase compared with their parental drug-sensitive cell lines. However, the greater susceptibility of drug-resistant cells to TNF alpha cytotoxicity was, in part, related to their decreased activities of manganese superoxide dismutase (MnSOD). Persistence of this differential sensitivity when MnSOD is inhibited by sodium nitroprusside (SNP) suggests that the greater susceptibility of drug-resistant cells to TNF alpha was not entirely due to their decreased level of MnSOD activity. K562 cl.6 and K/DAU600, which were more resistant to TNF alpha, both expressed greater levels of endogenous plasma membrane-bound TNF alpha than the CCRF-CEM cell line. All cell lines examined were (more or less) equal in susceptibility to the cytolytic effect of exogenous O2-. generated by xanthine/xanthine oxidase. These results demonstrate that both MnSOD and endogenous TNF alpha play a role in protecting leukaemic cells against TNF alpha cytotoxicity, but there is an unknown mechanism that causes drug-resistant cells to be more susceptible to TNF alpha cytotoxicity.

Preparation and Crystal Structures of Two Dimeric Lanthanoid(III) Complexes Containing Pyridinioacetate and 2,2'-Bipyridine Ligands:[Ln2( bpy )2( pybet )4(H2O)4] ( bpy )3(ClO4)6.H2O (Ln = Eu and Tb)

Two dimeric lanthanoid (III) complexes, [Ln2( bpy )2( pybet )4(H2O)4] ( bpy )3(ClO4)6.H2O ( bpy = 2,2′-bipyridine, pybet = pyridinioacetate, and Ln Eu and Tb), have been prepared and characterized by X-ray crystallography. The complexes are isostructural, each comprising a quadruply carboxylato -bridged, centrosymmetrical dimeric cation, six perchlorate anions, three uncoordinated bpy molecules and a lattice water molecule. Each Ln ion is surrounded in a distorted square-antiprismatic environment by four carboxylato oxygen atoms, two nitrogen atoms of the bidentate bpy ligand and two aqua ligands . The Ln-O bond lengths range from 2.33 to 2.44 Ǻ, and Ln-N bond lengths from 2.55 to 2.64 Ǻ. The uncoordinated bpy molecules are linked to the aqua ligands by hydrogen bonds.

[Effect of electroacupuncture on gastric acid secretion and gut hormones]

21 patients with mild type of chronic superficial gastritis were selected in this study. The effect of electroacupuncture in Zhongwan (RM12), Neiguan (P6) and Sanyinjiao (Sp6) on gastric acid secretion, serum gastrin, plasma somatostatin, plasma motilin concentration and erythrocyte acetylcholinesterase (AchE) activity were observed. The results were as follows: There were significant decreases in gastric acid output, serum gastrin concentration and AchE activity (P < 0.05), but no significant changes in plasma somatostatin and motilin concentration (P > 0.05) after simultaneous electroacupuncture in Zhongwan, Neiguan and Sanyinjiao.

[Choosing an intramuscular injection needle according to body type]

The sample of this study consisted of 360 patients with asthenic, sthenic or ortho-sthenic type. The thickness of hypodermic fat at dorsogluteal site was measured and the effect was compared. The result suggested that needle should be selected according to different habitus before intramuscular injection. The commonly used No. 6. 5 and No. 7 needle are not suitable for elderly females patients with ortho-sthenic type or male and female patients with sthenic type. For these kind of patients, a needle with a length of 35 mm, 40 mm or 45 mm should be used respectively in order to reach muscular tissues, have good effect, and reduce local pain and tissue hardening.

Image-directed and color Doppler studies of gallbladder tumors

Thirteen cases of primary adenocarcinoma of the gallbladder (GB), 1 of malignant fibrous histocytoma, 3 of metastatic adenocarcinoma, 5 of adenoma, 5 of polypus, 2 of xanthogranuloma, 6 of chronic cholecystitis, 4 of acute cholecystitis, and 8 of subacute cholecystitis were studied by image-directed and color Doppler ultrasonography (CDUS). All of the 14 cases of primary GB cancer (10 masses, 4 thickening wall) were found to have a high velocity arterial blood flow signal in the wall of the GB. In contrast, the 3 cases of metastatic cancer of the GB had no blood flow signal in the wall of the GB. For the 30 cases of benign lesions of the GB, only in 12 cases was a low velocity blood flow signal found. Nine of 10 cases of primary GB malignancy were found to have high velocity arterial blood flow signals in the tumor masses. No blood flow signal was observed in the masses of 13 cases (3 of metastatic adenocarcinoma, 5 of adenoma, 5 of polypus). An abnormal high velocity arterial blood flow signal observed within masses in the GB or in the GB wall is a significant feature of primary GB cancer and thus helps to differentiate primary GB cancer from metastatic and benign lesions of the GB.

Subaortic blind mitral pouch in a double-inlet right ventricle

A full-term baby girl was diagnosed at birth using echocardiography to have a single ventricle with common atrioventricular valve and subaortic ridge. On the 22nd day after birth she was admitted to hospital for intensive care after sudden onset of cyanosis. Three days later she died after repeated attacks of bradycardia. At necropsy the heart was examined by sequential segmental approach. Situs solitus with double-inlet right ventricle and ventriculoarterial discordance was revealed. The left atrial floor was separated from the ventricle by a small hole leading to a translucent blind pouch, which bulged toward the subaortic outflow tract with its hypoplastic tensor apparatus connected to the subaortic infundibulum. The aortic valve was normal. The pulmonary trunk with a competent bicuspid valve arose from the left-sided rudimentary left ventricle. The pulmonary blood flow was limited by a slit-like interventricular communication. Obstruction of the pulmonary venous return due to the natural closing of the patent foramen ovale and the mitral atresia led to her premature death.

Heat shock- and alkaline pH-induced proteins of Campylobacter jejuni: characterization and immunological properties

The protein response to physiological stress was characterized in Campylobacter jejuni 81176 after exposure to heat and pH shock and following periods of recovery. Immunoreactivities of major stress-related proteins were determined with anti-Campylobacter immune rabbit serum and intestinal lavage fluid. Distinct proteins with molecular masses ranging from 10 to 120 kDa were induced and/or released by selective heat or pH treatments. The most notable responses were those of two proteins with apparent molecular masses of 45 and 64 kDa that were induced and two other proteins of 10 and 12 kDa that were released by selective heat shock, alkaline pH treatment, or both. On the basis of N-terminal sequence analysis and immunological cross-reactivity data, the 64- and 10-kDa proteins were the C. jejuni homologs of Escherichia coli GroEL and GroES proteins, respectively. Enhanced chemiluminescence Western blotting (immunoblotting) revealed that all four proteins were among the major protein antigens recognized by anti-Campylobacter rabbit serum immunoglobulin G (IgG) and immune rabbit intestinal lavage IgA (secretory IgA). The results of this investigation suggest that the C. jejuni 10-, 12-, 45-, and 64-kDa proteins and a number of minor stress-related proteins deserve further evaluation of their respective roles in Campylobacter pathogenesis and immunity.

[Preparation of antibodies against zip product and the distribution of zip protein in Drosophila embryos]

Zip gene is required during the late neurogenesis of Drosophila. Molecular analysis of zip gene revealed that it encodes an integral membrane glycoprotein, functioning as a cellular recognition and/or adhesion molecule. It has been cloned into an expression plasmid pWR 590. By expression of this plasmid in E. coli, a fusion protein of zip with lacZ has been purified and used to prepare polyclonal antibodies from rabbits. After being identified by West blotting, antibodies were used to react with the whole mount embryos of Drosophila. The results of this antibody labelling experiment showed that zip proteins are fundamentally synthesized after germ band shortening, supporting our previous predication that zip gene is involved in the late neurogenesis and that antibodies against zip recognize lateral neural fascicles as well as neurons in CNS, proving that zip protein expressed in CNS may play a role in the establishment and maintenance of neural fasciculation.

[Evaluation of staging conformity CTNM and PTNM for lung cancer]

A series of 225 consecutive lung cancer patients were prospectively randomized into study group (75 patients) and control group (150 patients), and the conformity of CTNM and PTNM staging was was evaluated. Radical mediastinal lymph node dissection was performed and in average 11.5 nodes were dissected in the study group. Only suspected metastatic lymph nodes, 3.4 in average, were dissected in the control group. CTNM classification was made according to clinical examination, chest image examination and bronchoscopy in every patient and PTNM staging was made after thoracotomy. Then the conformity of CTNM and PTNM staging was examined by Kappa value. The results showed that the Kappa value in the two groups was lower than the effective standard value of 0.4. The study group (Kappa = 0.097) was poorer than the control group (Kappa = 0.371). The principal influencing cause was that N was not well evaluated by CTNM. The principal manifestation of the staging inconsistency was that the stage of PTNM was advanced than that of CTNM. In the study group 43% of patients showed an increased stage and this occurred in 33% of the control group (P < 0.05). The results of the study show that at present the CTNM staging has not fully satisfied the needs of practice and requires to be further improved. The operative procedure which only dissects suspected involved mediastinal lymph nodes can not meet the needs of PTNM staging. In order to make PTNM staging accurately and evaluate the results of treatment for lung cancer, radical mediastinal lymph node dissection should be performed in every operable patient.