[Effect of China Children's Asthma Action Plan on exercise in school-age children with bronchial asthma].

Objective: To investigate the effect of China Children's Asthma Action Plan (CCAAP) on the exercise status of school-age children with asthma. Methods: We included 400 school-age asthmatic children as research objects from CCAAP asthma management platform of the Affiliated Hospital of Qingdao University during March 1, 2018 to February 28, 2021 by simple random sampling method. The questionnaires of basic information and international physical activity were applied through WeChat or face to face investigation to collect the basic information and exercise status of the object. There were 346 valid questionnaires included in the study to compare the differences in exercise status and incidence of exercise-related asthma-like symptoms between the good and poor CCAAP application groups. Results: There were 232 (67.05%) and 114 (32.95%) cases in good and poor CCAAP application group, respectively. Age, female proportion and BMI of good CCAAP application group were (8±2) years, 47.0% (109/232) and (19.79±2.32) kg/m2, respectively, no statistic difference comparing to poor CCAAP application group [(8±2) years, 46.5% (53/114) and (19.87±2.43) kg/m2, respectively] (all P values>0.05). In good CCAAP application group, 30.18% (70/232) achieved the standard of moderate (high) intensity exercise per day, no statistic difference comparing to poor CCAAP application group [29.82% (34/112)] (P=0.947); 31.90% (74/232) participated in high-intensity exercise per week, higher than that of poor CCAAP application group [17.54% (20/112)] (P=0.005); incidence of exercise-related asthma-like symptoms was 19.83% (46/232), lower than that of poor CCAAP application group [29.82% (34/112)] (P=0.038). Conclusion: CCAAP promotes the exercise of school-age children with asthma.

[Evaluation of the efficacy of Chinese Children's Asthma Action Plan on the long-term management of children with asthma at home].

Objective: During the COVID-19 pandemic, the electronic "questionnaire star" was employed to investigate the general situation, medication situation and pandemic impact of children diagnosed with asthma in our hospital and enrolled in the electronic platform of the Chinese Children's Asthma Action Plan (CCAAP). The internet technology and big data were used to grasp the trend and asthma control of children who had been at home for a long time due to the pandemic, so as to facilitate the management. Methods: By random cluster sampling survey method, according to the needs and medication adherence score, the electronic "questionnaire star" was designed to conduct a survey among children (0 to 14 years old) who diagnosed with asthma and joined the CCAAP on the basis of bronchial asthma medication adherence scale. Finally, the results of electronic questionnaire survey were analyzed. Results: A total of 423 questionnaires were sent out, 422 of which were valid, with an effective response rate of 99.7%. The results of questionnaire survey showed that 296 cases were male, accounting for 70.1%, and 126 cases were female, accounting for 29.9%, with an average age of (5.4±2.6) years old. The average age of males and females was (5.3±2.6) and (5.4±2.6) years old, respectively. There were more children aged ≥5 years than children who were younger than 5 years. Additionally, 13.95% of the parents thought that the pandemic had more than moderate impact on children with asthma, and 76.12% of the children were in the green zone and had no asthma attack. The proportion of green zone inhaled drugs (79.8%) was higher than yellow zone and red zone (49.8%). After using the CCAAP platform, the dissatisfaction rate was only 1.42%. Moreover, 71.87% of the children's medical expenses decreased, and the proportion of frequent use and intermittent use of antibiotics reduced, however, the proportion of occasional use and never use of antibiotics increased significantly (all P<0.05). The average score of drug compliance was 4.56, and the more frequently the platform was used, the higher the score of medication compliance was (P<0.05). Conclusions: After using CCAAP management with the aid of internet technology, children with asthma who had been isolated at home for a long time were less affected by COVID-19, with high medication compliance, generally lower medical expenses, significantly reduced use of antibiotics, and high satisfaction. This management mode provides a new idea for internet medicine.

Biological false-positive venereal disease research laboratory test in cerebrospinal fluid in the diagnosis of neurosyphilis - a case-control study.

BACKGROUND: There is no clear consensus on the diagnosis of neurosyphilis. The Venereal Disease Research Laboratory (VDRL) test from cerebrospinal fluid (CSF) has traditionally been considered the gold standard for diagnosing neurosyphilis but is widely known to be insensitive. OBJECTIVE: In this study, we compared the clinical and laboratory characteristics of true-positive VDRL-CSF cases with biological false-positive VDRL-CSF cases. METHODS: We retrospectively identified cases of true and false-positive VDRL-CSF across a 3-year period received by the Immunology and Serology Laboratory, Singapore General Hospital. A biological false-positive VDRL-CSF is defined as a reactive VDRL-CSF with a non-reactive Treponema pallidum particle agglutination (TPPA)-CSF and/or negative Line Immuno Assay (LIA)-CSF IgG. A true-positive VDRL-CSF is a reactive VDRL-CSF with a concordant reactive TPPA-CSF and/or positive LIA-CSF IgG. RESULTS: During the study period, a total of 1254 specimens underwent VDRL-CSF examination. Amongst these, 60 specimens from 53 patients tested positive for VDRL-CSF. Of the 53 patients, 42 (79.2%) were true-positive cases and 11 (20.8%) were false-positive cases. In our setting, a positive non-treponemal serology has 97.6% sensitivity, 100% specificity, 100% positive predictive value and 91.7% negative predictive value for a true-positive VDRL-CSF based on our laboratory definition. HIV seropositivity was an independent predictor of a true-positive VDRL-CSF. CONCLUSION: Biological false-positive VDRL-CSF is common in a setting where patients are tested without first establishing a serological diagnosis of syphilis. Serological testing should be performed prior to CSF evaluation for neurosyphilis.

Patient Experience With Absolute Voice Rest Following Phonomicrosurgery: A Qualitative Study.

OBJECTIVE(S): Voice rest is commonly recommended following phonomicrosurgery to minimize vocal fold scarring, but associated quality of life (QoL) is low resulting in poor compliance. This study aimed to explore patients' experiences with voice rest following phonomicrosurgery to identify facilitators and barriers. METHODS: This qualitative study used prospective, typical case technique for purposive sampling of consecutive patients who underwent voice rest following phonomicrosurgery for benign vocal fold lesions. Participants were enrolled at a single tertiary Laryngology center located at Unity Health Toronto - St. Michael's Hospital from 2020 to 2022. Semi-structured virtual interviews were conducted 4 weeks following patients' surgery. All interview transcripts were transcribed verbatim and underwent thematic analysis. Participant recruitment was stopped once thematic saturation was achieved. RESULTS: Twenty participants were recruited and 4 withdrew due to scheduling conflicts. Sixteen participants completed interviews, all of whom reported minimal impact of postoperative voice rest on QoL. The participants attributed their success to facilitators such as notifying close contacts of their situation beforehand and adopting nonverbal forms of communication. No participant endorsed a negative attitude toward voice rest. Understanding the rationale for voice rest and the consequences of noncompliance were reported to be effective in encouraging compliance. CONCLUSION: Overall, the participants tolerated voice rest well owing to facilitators such as early preparation, lifestyle modifications, and understanding the rationale for voice rest. Social disconnect and work demands were barriers of voice rest. Moving forward, facilitators and barriers should be addressed in efforts to optimize the voice rest experience for future patient populations. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:361-366, 2024.

Influence of angiotensin-converting enzyme insertion/deletion polymorphism on nitric oxide production in hypertensives and hypercholesterolaemics.

UNLABELLED: WHAT IS NEW AND OBJECTIVE: Some evidence suggests that angiotensin-converting enzyme insertion/deletion (I/D) polymorphism may play a role in endothelium-dependent vasodilatation. However, the impact of I/D polymorphism on endogenous nitric oxide production, which may be of great therapeutic significance, has scarcely been studied. This study aimed to investigate this in hypertensives and hypercholesterolaemics. METHODS: Adult Han subjects were recruited by cluster sampling from two communities in Shunde, Guangdong province, China. Plasma nitrite and nitrate (NO(x)) levels were determined by colorimetry assay and angiotensin II and 6-keto-prostaglandin F1-alpha by radioimmunoassay. Angiotensin-converting enzyme gene I/D polymorphism were genotyped by polymer chain reaction-amplified fragment length polymorphism. RESULTS AND DISCUSSION: Of the 779 subjects who met our inclusion criteria, 502 were with normotensive and normocholesterolaemic, 76 had hypertension only, 146 hypercholesterolaemia only, and 55 had both hypertension and hypercholesterolaemia. Among subjects with hypertension only, the plasma levels of NO(x) for genotype DD were significantly lower than those for genotype II (P = 0·034). And the plasma levels of NO(x) for genotype DD was significantly higher than those for genotype II (P = 0·040) in subjects with hypercholesterolaemia only. WHAT IS NEW AND CONCLUSION: Our results suggest that I/D polymorphism has an impact on in vivo NO production in hypertensives and hypercholesterolaemics at the population level. Hypertensives with allele D may be benefit from L-arginine supplementation and hypercholesterolaemics with allele D may respond better to statins or antioxidants.

[Influence of five-in-one management mode on disease prevention and control of school children with asthma].

Objective: To investigate the influence of five-in-one management mode(standardized asthma treatment, asthma diary, peak expiratory flow (PEF) monitoring, reasonable diet and physical exercise) on disease prevention and control of school children with asthma. Methods: From April to October 2018, 70 children with asthma in clinical remission were selected from Affiliated Hospital of Qingdao University using randomized controlled study design. These children were randomly divided into study group and control group, with 35 cases in each group. In the study group, 5 cases were lost to follow-up, and 30 cases were actually enrolled. In the control group, 6 cases were lost to follow-up, and 29 cases were actually enrolled. Children in the control group received routine medication and regular outpatient consultation, and children in the study group received the five-in-one asthma management model. In the first time of seeing a doctor, after 3 months and 6 months of follow-up, asthma control test score, medication compliance index score and lung function index (forced expiratory volume in 1 second (FEV1), PEF were evaluated respectively.Parental satisfaction, asthma acute episodes, weight, height and biochemical index were recorded during the 6 months of follow-up. Pulmonary function index, asthma control score and body mass index of overweight children with asthma were compared with t-test, medication compliance was compared with chi-square test, and the rank sum test was used for the comparison of the number of emergency visits of asthma attacks and parents' satisfaction. Results: A total of 59 children with asthma were included, among them 30 were in the study group (8.1±1.5) years old and 29 in the control group (9.2±1.1) years old. After 3 months of follow-up, FEV1, PEF, asthma control score in the study group were (86.3±1.5)%, (83.3±2.4)%, (24.7±2.6) points respectively; and in the control group, FEV1, PEF, asthma control score were (84.4±2.5)%, (82.2±1.9)%, (21.1±1.3) points respectively. The indicators in the study group were higher than those in the control group (t=3.62, 1.97, 6.64, P<0.05). After 6 months of follow-up, FEV1, PEF, asthma control score in the study group were (88.4±2.3)%, (85.4±2.2)%, (26.8±1.8) points respectively; and in the control group, FEV1, PEF, asthma control score were (85.5±1.9)%, (83.2±1.7)%, (22.5±1.4) points respectively. The indicators in the study group were significantly higher than those in the control group (t=5.34, 4.24, 10.41, P<0.05). During the 6-month follow up, the number of emergency visits of asthma attacks in the study group and in the control group were 0.42(0.36, 0.51) and 0.92(0.72, 1.27) respectively. The indicator in the study group was significantly lower than that in the control group (Z=3.21, P<0.05). After 3 months of follow-up, the proportions of children with good compliance in the study group and control group were 67% (20/30) and 62% (18/29), the proportions of poor compliance were 27% (8/30) and 34% (10/29), the proportions of non-compliance were 7% (2/30) and 7% (2/29). There were no statistically significant differences (χ(2)=0.14, 0.43, 0.00, P=0.71, 0.51, 0.97). After 6 months of follow-up, the proportions of children with good compliance in the study group and control group were 87% (26/30) and 69% (20/29), the proportion of poor compliance were 10% (3/30) and 28% (8/29), the proportion of non-compliance were 3% (1/30) and 7% (2/29), There were no statistically significant differences (χ(2)=2.70, 3.00, 0.39, P=0.10, 0.08, 0.53). After 6 months of follow-up, the number of great satisfaction, satisfaction and dissatisfaction in the study group were 20, 10 and 0 respectively, the satisfaction rate was 100%, meanwhile those indicators in the control group were 4, 15 and 10 respectively, the satisfaction rate was 66%, The indicator in the study group was significantly higher than that in the control group (Z=4.60, P<0.05). Conclusions: The application of "five-in-one" asthma management model (standardized asthma treatment, asthma diary, PEF monitoring, reasonable diet and physical exercise) for school-age children with asthma can significantly improve lung function, as well as reduce the number of acute asthma attacks. It has a high parent satisfaction, therefore it should be recommended for clinical implementation.

Human p16gamma, a novel transcriptional variant of p16(INK4A), coexpresses with p16(INK4A) in cancer cells and inhibits cell-cycle progression.

The INK4A locus encodes two tumor suppressor genes, p16(INK4A) and p14(ARF), transcribed using alternative exons 1alpha or 1beta spliced onto the same exons 2 and 3. Both p16(INK4A) and p14(ARF) are capable of inhibiting the cell-cycle progression, albeit in different manner; p16(INK4A) is phosphorylation of retinoblastoma (pRB) dependent while p14(ARF) is p53-dependent. In this study, we report the discovery of a novel variant of p16(INK4A), termed p16gamma, in a primary T-cell acute lymphoblastic leukemia (T-ALL) patient sample and a neuroblastoma cell line, which was expressed at both the transcriptional and translational levels. Cloning and sequencing of the p16gamma cDNA revealed that p16gamma was identical to p16(INK4A), except that it contained an in-frame insertion of 197 bp between exons 2 and 3. p16gamma expression was detected in the majority of p16(INK4A)-expressing primary T-ALL and B-ALL patient samples and other p16(INK4A)-expressing tumor samples, but was only barely detectable in some normal mononuclear cells and other non-tumor samples. Structural analysis by nuclear magnetic resonance and circular dichroism confirmed that p16gamma, like p16(INK4A), is also an ankyrin-repeat protein. Functional analysis of p16gamma revealed that p16gamma protein interacted with cyclin D-dependent kinase4 and inhibited its kinase activity. Using a luciferase reporter assay, the transfection of p16gamma repressed the E2F response, the downstream target of pRB, with an efficacy equivalent to that of p16(INK4A). Moreover p16gamma, like p16(INK4A), induced cell-cycle arrest at G(0)/G(1), and inhibited cell growth in colony formation assay.

Molecular genetics of acute promyelocytic leukemia.

The remarkable success of retinoic acid in the treatment of acute promyelocytic leukemias and the subsequent discovery that mutant forms of a retinoid acid receptor (RARalpha) are invariably associated with this disease has generated considerable interest among both clinicians and basic scientists. Studies both in cell culture and in transgenic animals suggest that mutant RARs interfere with normal retinoid-mediated transactivation and granulocytic differentiation. More recently, a pivotal link between transcriptional silencing, the oncogenic functions of RAR mutants, and hormonal responses in APL patients has been established. These studies have greatly advanced our understanding of the molecular changes involved in leukemogenesis, have helped to reveal new aspects of cellular differentiation, and might lead to improved treatment strategies for human leukemias.

U4 small nuclear RNA dissociates from a yeast spliceosome and does not participate in the subsequent splicing reaction.

U4 and U6 small nuclear RNAs reside in a single ribonucleoprotein particle, and both are required for pre-mRNA splicing. The U4/U6 and U5 small nuclear ribonucleoproteins join U1 and U2 on the pre-mRNA during spliceosome assembly. Binding of U4 is then destabilized prior to or concomitant with the 5' cleavage-ligation. In order to test the role of U4 RNA, we isolated a functional spliceosome by using extracts prepared from yeast cells carrying a temperature-sensitive allele of prp2 (rna2). The isolated prp2 delta spliceosome contains U2, U5, U6, and possibly also U1 and can be activated to splice the bound pre-mRNA. U4 RNA does not associate with the isolated spliceosomes and is shown not to be involved in the subsequent cleavage-ligation reactions. These results are consistent with the hypothesis that the role of U4 in pre-mRNA splicing is to deliver U6 to the spliceosome.

Spliceosome activation by PRP2 ATPase prior to the first transesterification reaction of pre-mRNA splicing.

In addition to small nuclear RNAs and spliceosomal proteins, ATP hydrolysis is needed for nuclear pre-mRNA splicing. A number of RNA-dependent ATPases which are involved in several distinct ATP-dependent steps in splicing have been identified in Saccharomyces cerevisiae and mammals. These so-called DEAD/H ATPases contain conserved RNA helicase motifs, although RNA unwinding activity has not been demonstrated in purified proteins. Here we report the role of one such DEAH protein, PRP2 of S. cerevisiae, in spliceosome activation. PRP2 bound to a precatalytic spliceosome prior to the first step of splicing. By blocking the activity of a novel splicing factor(s), HP, which was involved in a post-PRP2 step, we found that PRP2 hydrolyzed ATP to cause a change in the spliceosome without the occurrence of splicing. The change was quite dramatic and could account for the previously reported differences between the precatalytic, pre-mRNA-containing spliceosome and the "active," intermediate-containing spliceosome. The post-PRP2-ATP spliceosome was further isolated and could carry out the subsequent reaction apparently in the absence of PRP2 and ATP. We hypothesize that PRP2 functions as a molecular motor, similar to some DExH ATPases in transcription, in the activation of the precatalytic spliceosome for the transesterification reaction.

Biochemical and genetic conservation of fission yeast Dsk1 and human SR protein-specific kinase 1.

Arginine/serine-rich (RS) domain-containing proteins and their phosphorylation by specific protein kinases constitute control circuits to regulate pre-mRNA splicing and coordinate splicing with transcription in mammalian cells. We present here the finding that similar SR networks exist in Schizosaccharomyces pombe. We previously showed that Dsk1 protein, originally described as a mitotic regulator, displays high activity in phosphorylating S. pombe Prp2 protein (spU2AF59), a homologue of human U2AF65. We now demonstrate that Dsk1 also phosphorylates two recently identified fission yeast proteins with RS repeats, Srp1 and Srp2, in vitro. The phosphorylated proteins bear the same phosphoepitope found in mammalian SR proteins. Consistent with its substrate specificity, Dsk1 forms kinase-competent complexes with those proteins. Furthermore, dsk1(+) gene determines the phenotype of prp2(+) overexpression, providing in vivo evidence that Prp2 is a target for Dsk1. The dsk1-null mutant strain became severely sick with the additional deletion of a related kinase gene. Significantly, human SR protein-specific kinase 1 (SRPK1) complements the growth defect of the double-deletion mutant. In conjunction with the resemblance of dsk1(+) and SRPK1 in sequence homology, biochemical properties, and overexpression phenotypes, the complementation result indicates that SRPK1 is a functional homologue of Dsk1. Collectively, our studies illustrate the conserved SR networks in S. pombe consisting of RS domain-containing proteins and SR protein-specific kinases and thus establish the importance of the networks in eucaryotic organisms.

Transcriptional regulation in acute promyelocytic leukemia.

It has been 10 years since the seminal discovery that a mutant form of a retinoid acid receptor (RARalpha) is associated with acute promyelocytic leukemia (APL). This finding, coupled with the remarkable success of retinoic acid (RA), the natural ligand of RARalpha, in the treatment of APL, has made APL a unique model system in the study of oncogenic conversion of transcription factors in hematological malignancies. Indeed, subsequent basic and clinical studies showed that chromosomal translocation involving the RARalpha gene is the cytogenetic hallmark of APL and that these mutant forms of RARs are the oncogenes in APL that interfere with the proliferation and differentiation pathways controlled by both RAR and their fusion partners. However, it was not until recently that the role of aberrant transcriptional regulation in the pathogenesis of APL was revealed. In this review, we summarize the biochemical and biological mechanisms of transcriptional regulation by mutant RARs and their corresponding wild-type fusion partner PML and PLZF. These studies have been instrumental in our understanding of the process of leukemogenesis in general and have laid the scientific foundation for the novel concept of transcription therapy in the treatment of human cancer.

A repetitive DNA sequence, rhs, responsible for duplications within the Escherichia coli K-12 chromosome.

A novel family of large, imperfectly repeated DNA sequences has been found in Escherichia coli. Two members of this family, rhsA and rhsB, occur as direct repeats, flanking the pit glyS xyl segment of the chromosome. Unequal sister-chromatid crossing over between rhsA and rhsB accounts for the frequent tandem duplication of the glyS locus that has been observed by various workers. This unequal recombination is recA-dependent. The rhsA locus is operationally defined as the segment between xyl and mtl that is repeated at other chromosomal locations. Using this definition, rhsA extends minimally 5500 base-pairs; 3800 base-pairs of rhsA are sufficiently homologous to rhsB to form an S1 nuclease-resistant heteroduplex with it. The rhsA sequence also exhibits internal repetition. At least one additional rhs sequence occurs in the E. coli chromosome unlinked to either rhsA or rhsB. Southern analysis of restriction digests of genomic DNA from E. coli strains C and B/5 showed that both of these strains have rhs hybridizable patterns similar to strain K-12, but the rhs sequence is absent in Salmonella typhimurium. The function of the rhs sequences has not been discovered. In the course of this work we developed a technique, termed "transductional walking", by which chromosomal DNA adjacent to a previously cloned DNA segment can be cloned through genetic procedures.

A mutation in a methionine tRNA gene suppresses the prp2-1 Ts mutation and causes a pre-mRNA splicing defect in Saccharomyces cerevisiae.

The PRP2 gene in Saccharomyces cerevisiae encodes an RNA-dependent ATPase that activates spliceosomes for the first transesterification reaction in pre-mRNA splicing. We have identified a mutation in the elongation methionine tRNA gene EMT1 as a dominant, allele-specific suppressor of the temperature-sensitive prp2-1 mutation. The EMT1-201 mutant suppressed prp2-1 by relieving the splicing block at high temperature. Furthermore, EMT1-201 single mutant cells displayed pre-mRNA splicing and cold-sensitive growth defects at 18 degrees. The mutation in EMT1-201 is located in the anticodon, changing CAT to CAG, which presumably allowed EMT1-201 suppressor tRNA to recognize CUG leucine codons instead of AUG methionine codons. Interestingly, the prp2-1 allele contains a point mutation that changes glycine to aspartate, indicating that EMT1-201 does not act by classical missense suppression. Extra copies of the tRNA(Leu)(UAG) gene rescued the cold sensitivity and in vitro splicing defect of EMT1-201. This study provides the first example in which a mutation in a tRNA gene confers a pre-mRNA processing (prp) phenotype.

Constitutive activation of transcription and binding of coactivator by estrogen-related receptors 1 and 2.

In this report, we demonstrate that, in contrast to most previously characterized nuclear receptors, hERR1 and hERR2 (human estrogen receptor-related protein 1 and -2) are constitutive activators of the classic estrogen response element (ERE) as well as the palindromic thyroid hormone response element (TRE(pal)) but not the glucocorticoid response element (GRE). This intrinsically activated state of hERR1 and hERR2 resides in the ligand-binding domains of the two genes and is transferable to a heterologous receptor. In addition, we show that members of the p160 family of nuclear receptor coactivators, ACTR (activator of thyroid and retinoic acid receptors), GRIP1 (glucocorticoid receptor interacting protein 1), and SRC-1 (steroid receptor coactivator 1), potentiate the transcriptional activity by hERR1 and hERR2 in mammalian cells, and that both orphan receptors bind the coactivators in a ligand-independent manner. Together, these results suggest that hERR1 and hERR2 activate gene transcription through a mechanism different from most of the previously characterized steroid hormone receptors.

Cloning and genetic characterization of an evolutionarily conserved human olfactory receptor that is differentially expressed across species.

We have cloned the full-length cDNA and genomic region of a human prostate specific G-protein coupled receptor with properties characteristic of an olfactory receptor. A partial cDNA sequence of this gene, called PSGR, was recently cloned. The gene contains two exons and one intron of 14.9 kb in its 5'untranslated region, and was mapped to human chromosome 11p15.2. A cluster of transcription initiation sites for the 2.8 kb PSGR mRNA was identified. Cloning of the homologous gene from the mouse revealed 93% amino acid homology between the human and mouse or rat (previously cloned as RA1c) proteins, and 99% identity between the rat and mouse homologs. Although northern analysis indicated expression of the human PSGR homolog was prostate specific, its mRNA could also be detected in the olfactory zone and the medulla oblongata of the human brain. In the mouse, the PSGR gene is predominantly expressed in the brain and colon. In the rat, the PSGR homolog is expressed in the liver in addition to the brain. These data add to the growing body of evidence suggesting that olfactory receptors may have functional roles in tissues other than the olfactory organ, and further, suggest that these functions may vary across species.

Involvement of catecholamines in recall of the conditioned NK cell response.

The primary goal of the study was to identify the types of catecholamines and the associated receptors which might be involved in the recall of the conditioned NK cell response. Specific catecholamine receptor antagonists were selected to block the conditioned NK cell response at the recall step. The regional contents of dopamine (DA), norepinephrine (NE), and epinephrine were determined in the brain of the conditioned animals by using the high performance liquid chromatography with electrochemical detection (HPLC/ED). Results showed that pre-disruption of the central alpha1-, alpha2-, beta1-, beta2-, D1-, or D2-receptors at the conditioned recall stage, interrupted the conditioned enhancement in NK cell activity. The NE contents at the cerebellum, and DA contents at the striatum and hippocampus, were significantly higher in the brain of the conditioned animals when compared to that of the control animals. These information indicated the possible roles of the central noradrenergic and dopaminergic systems in regulating the recall of the conditioned NK cell response.

A xanthine-based KMUP-1 with cyclic GMP enhancing and K(+) channels opening activities in rat aortic smooth muscle.

1. KMUP-1 (1, 3, 5 mg kg(-1), i.v.), a xanthine derivative, produced dose-dependent sustained hypotensive and short-acting bradycardiac effects in anaesthetized rats. This hypotensive effect was inhibited by pretreatment with glibenclamide (5 mg kg(-1), i.v.). 2. In endothelium-intact or denuded aortic rings preconstricted with phenylephrine, KMUP-1 caused a concentration-dependent relaxation. This relaxation was reduced by endothelium removal, the presence of NOS inhibitor L-NAME (100 microM) and sGC inhibitors methylene blue (10 microM) and ODQ (1 microM). 3. The vasorelaxant effects of KMUP-1 was attenuated by pretreatment with various K(+) channel blockers TEA (10 mM), glibenclamide (1 microM), 4-AP (100 microM), apamin (1 microM) and charybdotoxin (ChTX, 0.1 microM). 4. Increased extracellular potassium levels (30 - 80 mM) caused a concentration-related reduction of KMUP-1-induced vasorelaxations. Preincubation with KMUP-1 (1, 10, 100 nM) increased the ACh-induced maximal vasorelaxations mediated by endogenous NO release, and enhanced the potency of exogenous NO-donor SNP. 5. The vasorelaxant responses of KMUP-1 (0.01, 0.05, 0.1 microM) together with a PDE inhibitor IBMX (0.5 microM) had an additive action. Additionally, KMUP-1 (100 microM) affected cyclic GMP metabolism since it inhibited the activity of PDE in human platelets. 6. KMUP-1 induced a dose-related increase in intracellular cyclic GMP levels in rat A10 vascular smooth muscle (VSM) cells, but not cyclic AMP. The increase in cyclic GMP content of KMUP-1 (0.1 - 100 microM) was almost completely abolished in the presence of methylene blue (10 microM), ODQ (10 microM), and L-NAME (100 microM). 7. In conclusion, these results indicate that KMUP-1 possesses the following merits: (1) stimulation of NO/sGC/cyclic GMP pathway and subsequent elevation of cyclic GMP, (2) K(+) channels opening, and (3) inhibition of PDE or cyclic GMP breakdown. Increased cyclic GMP display a prominent role in KMUP-1-induced VSM relaxations.