Biomedical subjects

Xiaobin Zhang

Publications and source records attributed to Xiaobin Zhang.

At least 19 recordsLinked to original sources

PubMed2026

Efficacy of a high-frequency repetitive transcranial magnetic stimulation for craving reduction in adolescents with gaming disorder: a 4-week randomized control trial with 24-week follow-up.

BACKGROUND: With the widespread popularity of online gaming, gaming addiction has come under scrutiny. While there is ongoing research on the diagnosis and treatment of gaming disorder among adolescents, the clinical robustness and reliability of intervention strategies remain uncertain. METHODS: A 4-week, double-blind, randomized, sham-controlled clinical trial was conducted to evaluate the efficacy of noninvasive, high-frequency repetitive transcranial magnetic stimulation (rTMS) in alleviating psychological craving in adolescents diagnosed with gaming disorder. Sham rTMS was administered to the control group using the tilted-coil method. Both groups of participants were treated with SSRI medications. A total of 80 adolescents with gaming disorder participated in this study, and 73 ultimately completed the 24-week follow-up. The primary outcome was the change in craving levels before and after the rTMS intervention, as assessed by the Visual Analogue Scale (VAS). Secondary outcomes included changes in anxiety and depression levels before and after the intervention, as assessed by the HAMA and HAMD. RESULTS: We assessed levels of psychological craving, anxiety, and depression among adolescents with gaming disorder at baseline, after completing a 4-week intervention, and at a 24-week follow-up post-intervention. Our repeated-measures MANOVA results, adjusted for course variables, revealed a significant main effect of rTMS intervention on psychological craving levels in adolescents addicted to online games (F(11, 781) = 11.238, P < 0.001, partial η² = 0.142), as well as significant main effects on time (F(11, 781) = 6.809; P < 0.001, partial η² = 0.091) and group effects (F(1, 71) = 26.707, P < 0.001, partial η² = 0.282). In addition, repeated-measures ANOVA results showed significant time effects for anxiety (F(2, 142) = 20.747, P < 0.001, partial η² = 0.234) and depression levels (F(2, 142) = 22.277, P < 0.001, partial η² = 0.285) among adolescents with gaming disorder, with nonsignificant between-group effects and no intergroup interaction. In the active stimulation group, changes in psychological craving levels after 4 weeks of treatment were significantly and positively correlated with changes in anxiety levels after 4 weeks of treatment in adolescents addicted to online games (r = 0.335, P < 0.05). CONCLUSION: Our findings indicate that high-frequency rTMS targeting the left dorsolateral prefrontal cortex may be a promising approach for reducing psychological craving in adolescents with gaming disorder. TRIAL REGISTRATION: ChiCTR2500102979 in chictr.org.cn, registered on May 22, 2025.

Humans↗

PubMed2014

Combinatorial approaches for the identification of brain drug delivery targets.

The blood-brain barrier (BBB) represents a large obstacle for the treatment of central nervous system diseases. Targeting endogenous nutrient transporters that transcytose the BBB is one promising approach to selectively and noninvasively deliver a drug payload to the brain. The main limitations of the currently employed transcytosing receptors are their ubiquitous expression in the peripheral vasculature and the inherent low levels of transcytosis mediated by such systems. In this review, approaches designed to increase the repertoire of transcytosing receptors which can be targeted for the purpose of drug delivery are discussed. In particular, combinatorial protein libraries can be screened on BBB cells in vitro or in vivo to isolate targeting peptides or antibodies that can trigger transcytosis. Once these targeting reagents are discovered, the cognate BBB transcytosis system can be identified using techniques such as expression cloning or immunoprecipitation coupled with mass spectrometry. Continued technological advances in BBB genomics and proteomics, membrane protein manipulation, and in vitro BBB technology promise to further advance the capability to identify and optimize peptides and antibodies capable of mediating drug transport across the BBB.

Animals↗

PubMed2007

Nanorobotic spot welding: controlled metal deposition with attogram precision from copper-filled carbon nanotubes.

With the continuing development of bottom-up nanotechnology fabrication processes, spot welding can play a role similar to its macro counterpart for the interconnection of nano building blocks for the assembly of nanoelectronics and nanoelectromechanical systems (NEMS). Spot welding using single-crystalline copper-filled carbon nanotubes (CNTs) is investigated experimentally using nanorobotic manipulation inside a transmission electron microscope (TEM). Controlled melting and flowing of copper inside nanotube shells are realized by applying bias voltages between 1.5 and 2.5 V. The average mass flow rate of the copper was found to be 120 ag/s according to TEM video imaging (measured visually at approximately 11.6 nm/s through the CNT). Successful soldering of a copper-filled CNT onto another CNT shows promise for nano spot welding and thermal dip-pen lithography.

Copper↗

PubMed2005

Transport of nerve growth factor encapsulated into liposomes across the blood-brain barrier: in vitro and in vivo studies.

A nerve growth factor (NGF) was encapsulated into liposomes in order to protect it from the enzyme degradation in vivo and promote it permeability across the blood-brain barrier (BBB). RMP-7, a ligand to the B2 receptor on brain microvascular endothelial cells (BMVEC), was combined with 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-n-[poly(ethylenegly-col)]-hydroxy succinamide (DSPE-PEG-NHS) to obtain DSPE-PEG-RMP-7. Then DSPE-PEG-RMP-7 was incorporated into the liposomes' surface to target sterically stabilized liposomes (SSL-T) to the brain. The highest percent of NGF encapsulated into liposomes was about 34%, and the average size of liposomes was below 100 nm. A primary model of BBB was established and evaluated by morphological, permeability, and transendothelial electrical resistance (TEER). The BBB model was employed to study the permeability of NGF liposomes in vitro. The results indicated that the liposomes could enhance transport of NGF across the BBB. The best transport rate was received with NGF-SSL-T. The brain distribution of NGF liposomes was studied in vivo, the amount of NGF in the brain was increased in the order: NGF-SSL-T>NGF-SSL+RMP-7>NGF-SSL>NGF-L. The maximum concentration of NGF was recorded in 30 min following the intravenous injection. In particular, a majority of NGF was distributed in striatum, hippocampus and cortex, and the concentration of NGF was relatively lower in olfactory bulb, cerebellum and brain stem. There was a close relationship between P(e) (permeability coefficient on in vitro BBB model) and T(e) (brain targeted coefficient in vivo) for NGF encapsulated into the liposomes.

Animals↗

PubMed2004

Decreased neointimal formation in Nox2-deficient mice reveals a direct role for NADPH oxidase in the response to arterial injury.

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are produced, in part, from NADPH oxidase in response to host invasion and tissue injury. Defects in NADPH oxidase impair host defense; however, the role of ROS and RNS in the response to tissue injury is not known. We addressed this issue by subjecting leukocyte oxidase (Nox2)-deficient (Nox2-/-) mice to arterial injury. Femoral artery injury was associated with increased Nox2 expression, ROS/RNS production, and oxidative protein and lipid modification in wild-type mice. In Nox2-/- mice, RNS-mediated protein oxidation, as monitored by protein nitrotyrosine content, was significantly diminished. This was accompanied by reduced neointimal proliferation, as monitored by intimal thickness and intimal/medial ratio, in Nox2-/- compared to wild-type mice. In addition, Nox2 deficiency led to reduced cellular proliferation and leukocyte accumulation. These data indicate that Nox2-mediated oxidant production has a requisite role in the response to tissue injury.

Animals↗

PubMed2004

The mouse FKBP23 binds to BiP in ER and the binding of C-terminal domain is interrelated with Ca2+ concentration.

FK506 binding protein 23 from mouse (mFKBP23) is a peptidyl-prolyl cis-trans isomerase (PPIase) from the endoplasmic reticulum (ER), which consists of an N-terminal PPIase domain and a C-terminal domain with Ca(2+) binding sites. The assay of adsorption from ER extract with glutathione S-transferase-mFKBP23 attached to glutathione-Sepharose 4B shows that mFKBP23 binds to mouse immunoglobulin binding protein (mBiP). The same assay with the recombinant proteins of the N- and C-termini of mFKBP23 shows that the binding of the C-terminus is Ca(2+)-dependent and the switch point is between 2 and 3 mM. By high concentration of Ca(2+) this binding cannot be detected. Furthermore, the Ca(2+)-regulated binding of mFKBP23 and mBiP in ER can be detected by means of co-immunoprecipitation.

Animals↗

PubMed2004

Evidence for a role of macrophage migration inhibitory factor in vascular disease.

OBJECTIVE: Inflammation plays an essential role in atherosclerosis and restenosis. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that is widely expressed in vascular cells. However, there is no in vivo evidence that MIF participates directly in vascular injury and repair. Therefore, we investigated the effect of MIF blockade on the response to experimental angioplasty in atherosclerosis-susceptible mice. METHODS AND RESULTS: Carotid artery dilation (2.5 atm) and complete endothelial denudation were performed in male C57BL/6J LDL receptor-deficient mice treated with a neutralizing anti-MIF or isotype control monoclonal antibody. After 7 days and 28 days, intimal and medial sizes were measured and intima/media area ratio (I/M) was calculated. Intimal thickening and I/M were reduced significantly by anti-MIF compared with control antibody. Vascular injury was accompanied by progressive vessel enlargement or "positive remodeling" that was comparable in both treatment groups. MIF blockade was associated with reduced inflammation and cellular proliferation and increased apoptosis after injury. CONCLUSIONS: Neutralizing MIF bioactivity after experimental angioplasty in atherosclerosis-susceptible mice reduces vascular inflammation, cellular proliferation, and neointimal thickening. Although the molecular mechanisms responsible for these effects are not yet established, these data prompt further research directed at understanding the role of MIF in vascular disease and suggest novel therapeutic interventions for preventing atherosclerosis and restenosis.

Angioplasty, Balloon↗

PubMed2004

GP IIb/IIIa inhibition with eptifibatide lowers levels of soluble CD40L and RANTES after percutaneous coronary intervention.

Platelets are the most abundant blood source of CD40L, a proinflammatory and prothrombotic costimulatory molecule implicated in atherosclerosis. Agonist stimulation results in the secretion of a soluble form of CD40L (sCD40L) and GP IIb/IIIa receptor inhibition blocks secretion of sCD40L in vitro. However, the effect of GP IIb/IIIa inhibition on sCD40L levels in humans is unknown. Plasma sCD40L and inflammatory markers were measured (t = 0, 0.5, 2, and 24 hr post-PCI) in a cohort of patients receiving abciximab (n = 15), eptifibatide (n = 15), or no GP IIb/IIIa inhibitor (n = 15). PCI in the absence of GP IIb/IIIa inhibitor was associated with a small but measurable rise in sCD40L and the platelet-derived chemokine RANTES. In contrast, eptifibatide significantly lowered baseline sCD40L (P = 0.018) and RANTES (P = 0.006) levels. This effect was not observed with abciximab. GP IIb/IIIa inhibition with eptifibatide lowers levels of sCD40L and RANTES post-stenting, possibly conferring anti-inflammatory as well as antithrombotic effects.

Abciximab↗

PubMed2004

Integrin engagement regulates monocyte differentiation through the forkhead transcription factor Foxp1.

The precise signals responsible for differentiation of blood-borne monocytes into tissue macrophages are incompletely defined. "Outside-in" signaling by integrins has been implicated in modulation of gene expression that affects cellular differentiation. Herein, using differential display PCR, we have cloned an 85-kDa forkhead transcription factor (termed Mac-1-regulated forkhead [MFH] and found subsequently to be identical to Foxp1) that is downregulated in beta(2)-integrin Mac-1-clustered compared with Mac-1-nonclustered monocytic THP-1 cells. MFH/Foxp1 is expressed in untreated HL60 cells, and its expression was markedly reduced during phorbol ester-induced monocyte differentiation, but not retinoic acid-induced granulocyte differentiation. Overexpression of MFH/Foxp1 markedly attenuated phorbol ester-induced expression of c-fms, which encodes the M-CSF receptor and is obligatory for macrophage differentiation. This was accompanied by decreased CD11b expression, cell adhesiveness, and phagocytosis. Using electromobility shift and reporter assays, we have established that MFH/Foxp1 binds to previously uncharacterized sites within the c-fms promoter and functions as a transcriptional repressor. Deficiency of Mac-1 is associated with altered regulation of MFH/Foxp1 and monocyte maturation in vivo. Taken together, these observations suggest that Mac-1 engagement orchestrates monocyte-differentiation signals by regulating the expression of the forkhead transcription repressor MFH/Foxp1. This represents a new pathway for integrin-dependent modulation of gene expression and control of cellular differentiation.

Amino Acid Sequence↗

PubMed2004

[Concealed penis and its surgical correction: a report of 63 cases].

OBJECTIVE: To evaluate the basic principles of surgical correction of concealed penis. METHODS: From Jan. 1999 to Dec. 2002, 63 cases of concealed penis, aged from 1 year and 6 months to 19 years with a mean age of 7 years and 2 months, were corrected with two different approaches: 37 cases of group A with obesity were corrected by anchoring micrus tissue onto the pubis at the base of the penis, and 26 cases of group B by fixing the subcutateous tissues at both sides of the penile shaft to the deep tunica albuginea at the penile root. Then prepuce plasty was carried out. RESULTS: Six-month postoperative follow-up found adequate exposure of the penis in all of group A, prepuce oedema in 7 cases, abdomen fat liquidization in 3 cases, unsatisfactory recovery of incision hollow in 3 cases and patchy numbness of the glans in 1 case. The 25 cases of group B had satisfactory exposure of the penis, with no obvious prepuce oedema, 1 case with retraction of the penis 7 days after operation. CONCLUSIONS: Various surgical procedures could be adopted for concealed penis, and the key to the satisfactory appearance is the restoration of penile tunicae and the fixation at the base of the penis. Further study is needed to determine the natural history of these disorders as well as which conditions and what age will benefit most from surgical intervention.

Adolescent↗

PubMed2004

[Effects of prostadyn sabale capsules on chronic prostatitis].

OBJECTIVE: To study the effects of prostadyn sabale capsules on chronic prostatitis (CP). METHODS: One hundred and twenty-five CP cases were divided into three categories according to National Institutes of Health (NIH) concensus definition and classification of CP:31 of category II. 75 of category IIIA and 19 of category IIIB. All the cases were treated with prostadyn sabale capsules at the dosage of 320 mg twice a day. NIH chronic prostatitis symptom index (NIH-CPSI), routine examination and culture of expressed prostatic secretions (EPS) were prospectively evaluated before and after treatment. RESULTS: The cure rates of category II, category IIIA and category IIIB were 25.8%, 16.0%, and 21.1% respectively, the general cure rate being 19.2%. The alleviation rate was 63.5% and the total effectivity rate was 82.7%. No side effects were observed. CONCLUSIONS: Prostadyn sabale capsules have good effects on CP.

Adult↗

PubMed2004

[Transplantation of adrenocortical cells in allorat using porous PHB as cell carrier].

This experiment was designed to investigate the feasibility of transplanatation of using porous PHB as cell carrier for the transplanatation of adrenocortical cells. Adrenocortical cells from rat adrenal gland were separated and cultured in vitro. The effect of PHB on the proliferation and secretory function of adrenocortical cells were evaluated by MTT and RIA methods. Then adrenocortical cells were seeded into porous PHB. After the cells were cultured in vitro for about seven days, they were implanted into the rats having undergone bilateral adrenalectomy. The changes of blood corticosterone and aldosterone and the local histological changes in these rats were observed. Adrenocortical cells were able to grow and survive on PHB. No effect on the proliferation and secretory function of adrenocortical cells were observed. Most bilateral adrenalectomized rats bearing the transplanted adrenocortical cells within PHB (study group) survived longer than did the adrenalectomized rats in control group. The blood corticosterone level and aldosterone level of study group were higher than those of control group. It was found that PHB has no effects on the survival, proliferation and secretory function of adrenocortical cells. Adrenocortical cells within PHB can survive a period of time and can secrete corticosterone and aldosterone which can meet the needs of the adrenalectomized rats. PHB can degrade slowly in vivo. It is feasible to perform transplantation of adrenocortical cells using porous PHB as cell carrier.

Adrenal Cortex↗

PubMed2004

[Transperineal puncture drug injection in the treatment of chronic prostatitis].

OBJECTIVE: To investigate the effect of transperineal puncture drug injection in the treatment of chronic prostatitis. METHODS: Forty cases of chronic prostatitis underwent transperineal puncture drug injection. Bacterial culture and antimicrobial agent sensitivity tests were conducted on the prostatic fluid of the patients. A sensitive antimicrobial agent was selected, mixed with lidocaine and dexamethasone, and injected transperineally into the prostate at intervals of 7 days and 4 times as one course. After one month, the effect was evaluated and the patients were followed up for 6 months. RESULTS: Among the 40 cases, the cure rate was 52.5% (21/ 40), the alleviation rate 40% (16/40), the nullify rate 7.5% (3/40) and the total effectivity rate 92.5%. No relapse was found in the 28 followed-up cases. CONCLUSION: Transperineal puncture drug injection is a safe and effective way in the treatment of chronic prostatitis.

Adult↗

PubMed2003

Targeting platelet-leukocyte interactions: identification of the integrin Mac-1 binding site for the platelet counter receptor glycoprotein Ibalpha.

The firm adhesion and transplatelet migration of leukocytes on vascular thrombus are dependent on the interaction of the leukocyte integrin Mac-1 (alphaMbeta2, CD11b/CD18) and the platelet counter receptor glycoprotein (GP) Ibalpha. Previous studies have established a central role for the I domain, a stretch of approximately 200 amino acids within the alphaM subunit, in the binding of GP Ibalpha. This study was undertaken to establish the molecular basis of GP Ibalpha recognition by alphaMbeta2. The P201-K217 sequence, which spans an exposed loop and amphipathic alpha4 helix in the three-dimensional structure of the alphaMI domain, was identified as the binding site for GP Ibalpha. Mutant cell lines in which the alphaMI domain segments P201-G207 and R208-K217 were switched to the homologous, but non-GP Ibalpha binding, alphaL domain segments failed to support adhesion to GP Ibalpha. Mutation of amino acid residues within P201-K217, H210-A212, T213-I215, and R216-K217 resulted in the loss of the binding function of the recombinant alphaMI domains to GP Ibalpha. Synthetic peptides duplicating the P201-K217, but not scrambled versions, directly bound GP Ibalpha and inhibited alphaMbeta2-dependent adhesion to GP Ibalpha and adherent platelets. Finally, grafting critical amino acids within the P201-K217 sequence onto alphaL, converted alphaLbeta2 into a GP Ibalpha binding integrin. Thus, the P201-K217 sequence within the alphaMI domain is necessary and sufficient for GP Ibalpha binding. These observations provide a molecular target for disrupting leukocyte-platelet complexes that promote vascular inflammation in thrombosis, atherosclerosis, and angioplasty-related restenosis.

Amino Acid Sequence↗

PubMed2003

The study on brain targeting of the amphotericin B liposomes.

To improve transporting drugs across the Blood Brain Barrier (BBB) into the brain, RMP-7 was conjugated to the surface of liposomes containing Amphotericin B (AmB) for cerebral inflammation, because it can selectively bound to the B2 receptors on the capillary blood vessel. First, RMP-7 was conjugated to DSPE-PEG-NHS [1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-n-[poly (ethylenegly-col)]-hydroxy succinamide, PEG M 3400] under mild condition to obtain a predominantly 1:1 conjugate (DSPE-PEG-RMP-7), as evidenced by the Matrix-Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS). The second, endothelium cell was cultured on the cell insert to form an in vitro BBB model and the stereoscan microscope, electric resistance and permeation of horse-radish peroxidase (HRP) across the endothelium cell monolayer were used as indicators to evaluate the integrality of the monolayer, and then the in vitro BBB model was used to determine the bioactivity of DSPE-PEG-RMP-7 "opening" BBB. The results demonstrated the in vitro BBB model was set up, RMP-7 and DSPE-PEG-RMP-7 could improve the transporting of HRP across the BBB. The third, the liposomes containing AmB (AmB-L-PEG) was prepared by modified Film-sonication method and DSPE-PEG-RMP-7 was used to modify the AmB-L-PEG to obtain AmB-L-PEG-RMP-7. The fourth, tissue distribution of AmB in the rats of three groups was determined: Group I, AmB-L-PEG; Group II, AmB-L-PEG+RMP-7 (the physical mixture of AmB-L-PEG and RMP-7); Group III, AmB-PEG-RMP-7. The drugs were transfused into the rats through the femoral vein. The concentration of AmB in the tissue was checked using High-Performance Liquid Chromatography (HPLC) method. The rank of AmB concentration in the brain were as follows: III>II>I. The AmB concentration in the liver, spleen, lung and kidney had no significant difference. The concentration of AmB in the brain of the group III was raised several times higher than that in the other two groups, because the DSPE-PEG-RMP-7 had been inserted in the surface of AmB-L-PEG. Both the RMP-7 and AmB-L-PEG could reach BBB at the same time. When RMP-7 selectively reacted with the B2 receptor, the BBB is "opened" and AmB was transported into the brain at the same time. While in group II, the RMP-7 could improve the AmB concentration in the brain a little, because the RMP-7 and liposomes could not reach BBB at the same time. The distribution of AmB in the tissues demonstrated that the RMP-7 and its derivative had selectivity to the brain.

Aminoglycosides↗

PubMed2003

[Pharmacogenetic assessment of antipsychotic-induced tardive dyskinesia: contribution of 5-hydroxytryptamine 2C receptor gene and of a combination of dopamine D3 variant allele (Gly) and MnSOD wild allele (Val)].

OBJECTIVE: To further investigate whether the functional polymorphisms of dopamine D2 receptor (DRD2) and dopamine D3 receptor (DRD3) genes associate with the development of tardive dyskinesia (TD) in schizophrenia, and whether the interactive effects of DRD2, DRD3, 5-hydroxytryptamine 2C receptor (HTR2C) and manganese superoxide dismutase (MnSOD) genes contribute to the severity of TD. METHODS: The patients with schizophrenia were assessed for TD by the Abnormal Involuntary Movement Scale (AIMS). Eventually, 42 schizophrenics with persistent TD were in the TD group, and 59 schizophrenics without TD were in the non-TD group. The polymorphism of each candidate gene was analyzed using a polymerase chain reaction-based restriction fragment length polymorphism analysis. RESULTS: The genotype distributions of the candidate genes in the groups were all consistent with the Hardy-Weinberg equilibrium. Allele frequencies for -759C/T and -697G/C polymorphisms in HTR2C gene showed a significant excess of -697 variant (P<0.05) in the patients with TD, compared against those in patients without TD. There were no differences in the distributions of the allelic frequencies and genotypes of Taq I. A polymorphism in DRD2 gene, of Ser/Gly polymorphism in DRD3 gene, and of Ala-9Val polymorphism in MnSOD gene between the TD group and non-TD group (P>0.05). Interestingly, as compared with the other joint allelic types, a significant excess of carrying both DRD3 variant allele (Gly) and MnSOD wild allele (Val) was found in the TD group (P<0.05). However, neither the allele and genotypes nor the clinical demographic characteristics contributed to the higher total AIMS scores in the patients of the TD group. There were no significant differences in any of the clinical demographic characteristics between the subgroups of any genotype in TD and non-TD groups. CONCLUSION: The excess of -697 variant in the promoter regulation region of the HTR2C gene may be a risk factor for the susceptibility to the occurrence of TD in Chinese male patients with schizophrenia. A combination of DRD3 variant allele (Gly) and MnSOD wild allele (Val) may increase the susceptibility to the development of TD.

Aged↗

PubMed2003

[Experimental study on olfactory evoked potential in rabbits].

OBJECTIVE: To observe olfactory evoked potential(OEPs) produced by electrical stimulation of the olfactory mucosa and to find out an objective way to appraise olfactory function. METHOD: A bipolar stimulus electrode was placed on the olfactory mucosa of adult health rabbits via anterior naris. Olfactory evoked potential was recorded at headtop after being given a 0.5-4.0 mA current to the mucosa. And we also investigated the effect of stimulus parameters and stimulus location to the wave form of OEPs. RESULT: Triphasic negative-positive-negative evoked potentials were recorded from the surface of the frontal head close to olfactory bulb. Latent period of three waves respectively was N(1)20.6 ms, P(1)33.5 ms, N(2)58.3 ms. CONCLUSION: In general, the OEPs were composed of triphasic negative-positive-negative complexes. The waveforms were stable and could be repeated well. Each parameter was useful for estimating the olfactory function.

Animals↗

PubMed2002

[Association of antipsychotic agent-induced weight gain with a polymorphism of the promotor region of the 5-HT2C receptor gene].

OBJECTIVE: To determine whether 5-hydroxytryptamine 2C (5-HT2C) receptor gene 759C/T polymorphism influences the weight gain following antipsychotic agents (APS) treatment in patient with schizophrenia. METHODS: DNA was extracted from the peripheral blood of 117 Chinese first-episode patients of Han nationality with schizophrenia diagnosed according to CCMD-II-R criteria. PCR-RELP technique was used to analyse the frequencies of 5-HTR2C receptor gene 759C/T hemizygote (male) and genotype (female). Monotherapy with APS (chlorpromazine or rispperidone) was given for 10 weeks. The body weight was taken and body mass index (BMI) was calculated on admission and every week subsequently for each patient. The correlation of hemizygote or genotype and the BMI was analyzed. RESULTS: Ten weeks after treatment, there was an average increase in body weight of (3.2 +/- 3.5) kg or (5.7 +/- 6.2)% of the baseline weight with a range of -7 kg approximately 12 kg or -7.8% approximately 32%. The frequency of mutant hemizygote was 58% among the 58 male subjects; the frequency of mutant homozygote was 0%, and the frequency of mutant heterozygote was 27.0% among the 59 female subjects. The body weight gain > 7% occurred in 53% of wild type hemizygote males and 47% of wild type homozygote females; and only 18% of mutant hemizygote males and 13% of mutant heterozygote females. The proportions of 759T hemizygote males or heterozygote females in those with body weight gain > 7% and those with body weight < 7% were significantly different (chi(2) = 22.35, v1, P = 0.000 1; chi(2) = 12.36, v1, P = 0.000 1). Patients without mutant allele were five to six times more likely to develop substantial weight gain (OR = 5.11, 6.68). CONCLUSION: The 5-HT2C-receptor gene -759C/T polymorphism is associated with APS-induced weight gain. 759C-->T may be a protective factor for the development of weight gain in Chinese schizophrenic patients of Han nationality.

Adolescent↗