Objective To study the expression of O6-methylguanine-DNA methyltransferase (MGMT) and its clinicopathological significance in thyroid cancer.Methods Immunohistochemistry was used to determine the expression of MGMT in 61 thyroid cancer tissues, 21 thyroid adenomas, 15 Hashimoto's thyroiditis, 8 nodular goiter, and 12 peri-tumor tissues. Results There was statistic difference in the expression of MGMT between the normal tissues and thyroid cancers (P＜0.05). Expression of MGMT increased from the normal tissue (16.67%, 10/12), nodular goiter (25.00%, 2/8), Hashimoto's thyroiditis (60.00%, 9/15), and thyroid adenoma (52.38%, 11/21)to thyroid cancer (60.66%, 38/61). Expression of MGMT in papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC) had significant difference (P＜0.05), and the expression level of MGMT decreased with the malignancy of thyroid cancer, such as in PTC (72.22%, 26/36), and FTC (50.00%, 8/16). There was no statistic difference in MGMT expression in sex, age, and nationality (P＞0.05).Conclusion High expression of MGMT might be related to the malignancy of thyroid cancer, which may be one of the diagnosis indexes for thyroid cancer. It will be a common clinical index in diagnosingthyroid cancer since there is no difference in MGMT expression among sexes, ages, and nationalities.

The resident match system established in 1952.And since then almost all of the senior medical students and international students have applied a position of resident training in this national system.They seek a respective resident program and hospital for training while the hospital hires students they preferred.The match procedure includes submitting application,interview of selected candidates,submitting rank-order list of both parties,centralizing matching service by computer and announcement of the results in Match Day.This is a relatively stan-dardized,rational and fair system which we can learn something from.

Abstract: Objective　To investigate the pollution characteristics of major heavy metals in PM2.5 in urban areas of Haikou City, and to assess their potential health risks to humans. Methods　From 2021 to 2022, samples of atmospheric PM2.5 were monthly collected from the typical urban areas of Haikou, and the concentrations of nine heavy metal elements including arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), nickel (Ni), copper (Cu), vanadium (V), and zinc (Zn) were measured using the inductively coupled plasma mass spectrometry (ICP-MS). The health risk assessment of these heavy metals was conducted using a health risk model. Results　The average mass concentration of PM2.5 in Haikou was (20.506±13.054) µg/m³, with a range of 4.000 to 64.000 µg/m³ during the year 2021 and 2022. The PM2.5 concentrations showed significant seasonal variations: highest in winter, followed by autumn and spring, and lowest in summer. The total concentration of the nine heavy metal elements ranged from 0.030 to 138.000 ng/m³, with Zn, Mn, and Pb having the highest concentrations, particularly notable during the autumn and winter seasons. Enrichment factor (EF) analysis indicated moderate enrichment (10 Cd > Cr > As > Pb > V > Zn > Cu > Ni. The total non-carcinogenic hazard index (HI) ranged from 0.171 to 0.361. The inhalation incremental lifetime carcinogenic risk values (ILCR) for the four elements Cr, As, Cd, and Ni ranged from 2.911×10-7 to 1.558×10-5, with ILCR decreasing in that order. The total carcinogenic risk index (TR) varied between 1.502×10-5 and 3.169×10-5, with risk intensities for HI and TR in the order: children > adult males > adult females. Conclusions　The average PM2.5 concentration in the Haikou urban area is lower than the 24-hour average concentration limit of Grade I (35 µg/m3) in the "Environmental Air Quality Standard" (GB 3095-2012), but still higher than the control standard recommended by the WHO in 2021 (15 µg/m3). The non-carcinogenic health risks of the nine heavy metal elements detected in PM2.5 are not significant, but Cr and As have potential carcinogenic risks, with children being more vulnerable than other populations.

Objective:To analyze the rules and characteristics of acupoints selection in acupuncture RCT literature on therapy of Bell palsy.Methods:Acupuncture Prescription Database was established through collecting RCT literature of acupuncture treatment of Bell palsy.The characteristics and rules of acupoints selection were investigated by means of data mining method.Results:After data mining-based analysis on acupuncture therapy of Bell palsy,we found that points on Yangming Meridians were frequently used,especially ST 4.Selection of local acupoints and distal points were important.Conclusion:According the means of data mining,the results revealed that acupoints selection along related meridian was the important principle for Bell palsy,and the special acupoints were the main part of prescriptions.

Objective To evaluate the effect of alprostadil on acute lung injury in septic rats. Methods Thirty adult male Sprague?Dawley rats, weighing 200-250 g, were randomly divided into 3 groups (n=10 each) using a random number table: sham operation group (group S), acute lung injury group ( group ALI) , and alprostadil group ( group Q) . The animals were anesthetized with intraperitoneal 1% pentobarbital sodium 5 ml∕100 g. Sepsis was induced by cecal ligation and puncture. In group Q, al?prostadil ( 10 μg∕2 ml) 2 ml∕kg was injected via the tail vein at 30 min before cecal ligation and puncture. The equal volume of normal saline was given in S and ALI groups. At 24 h after operation, blood samples were taken for determination of serum tumor necrosis factor?alpha ( TNF?α) and interleukin?6 ( IL?6) con?centrations by enzyme?linked immunosorbent assay. The animals were then sacrificed. The left lungs were immediately removed for microscopic examination, and the right lungs were immediately removed for deter?mination of wet∕dry lung weight ratio ( W∕D ratio ) , and expression of TNF?α mRNA and high mobility group box?1 ( HMGB1) using real?time reverse transcriptase?polymerase chain reaction. Results Com?pared with group S, the concentrations of serum TNF?α and IL?6 were significantly increased, and the ex?pression of TNF?α mRNA and HMGB1 mRNA was up?regulated, and W∕D ratio was increased in ALI and Q groups ( P<0?05) . Compared with group ALI, the concentrations of serum TNF?αand IL?6 were signifi? cantly decreased, and the expression of TNF?α mRNA and HMGB1 mRNA was down?regulated, and W∕D ratio was decreased in group Q ( P<0?05) . The pathological changes of left lungs were significantly attenua?ted in group Q as compared with group ALI. Conclusion Alprostadil can reduce acute lung injury in septic rats, and the mechanism may be related to down?regulation of HMGB1 expression and inhibition of inflam?matory responses.

Objective To examine aortic dissection by using T1W/TFE sequence and to observe the imaging characteristics of aortic dissection in T1W/TFE sequence. Methods Twenty patients confirmed as aortic dissection by CT and ultrasound received MRI scanning of T1W/TFE sequence on inclined sagittal and SE sequence on transaxial at Philips Gyroscan 1.5 MR imager. The signal changes of aortic dissection in T1W/TFE sequence were observed. Results In T1W/TFE sequence, we observed not only an intimal flap, a double lumen and range of aortic dissection, but also the site of intimal tear and thrombus in the false lumen. Conclusion By using T1W/TFE sequence we obtained the high quality image of aortic dissection and high contrast of imaging. Combined with SE sequence , T1W/TFE sequence can provide reliable information for analyzing and curing aortic dissection in clinic.

Objective To understnad the defense mechanisms of patients with borderline personality disorder (BPD) and to explore its relationship with childhood abuses.Methods One hundred and forty-two outpatients with BPD (group A),63 outpatients with other personality disorders (group B) and 20 outpatients without any Axis Ⅱ diagnoses (group C) were enrolled and completed Chinese versions of the Childhood Experience of Care and Abuse Questionnaire (CECA.Q) and the Defensive Style of Questionnaire (DSQ).Multivariate analysis of variance and Pearson correlation analysis were used for data analysis.Results Compared to group B and C,the score of defense mechanisms reported by group A were significantly increased in all eight premature defense mechanisms,such as projection(F =26.5,P ＜ 0.05),passive aggression (F =18.1,P ＜ 0.05),acting out (F =28.3,P ＜ 0.05),complaint (F =16.7,P ＜0.05),fantasy(F =16.3,P ＜ 0.05),splitting (F =28.8,P ＜ 0.05),withdrawal (F =8.3,P ＜ 0.05),somatization(F=7.6,P ＜ 0.05),and part of the middle defense mechanisms,such as omnipotence-devaluation(F =9.2,P ＜ 0.05),isolation(F =4.7,P ＜ 0.05) and identification (F =10.0,P ＜ 0.05).At the same time,the BPD patients got lower scores in the mature defense mechanisms,such as sublimation (F =4.1,P ＜ 0.05) and repression(F =3.9,P ＜ 0.05).Those who experienced physical abuse use more complaint (F =6.9,P ＜ 0.05),denial mechanisms (F =5.2,P ＜ 0.05) and less anticipation one (F =4.6,P ＜ 0.05).Those who experienced sexual abuse use more somatization (F =4.4,P ＜ 0.05) and isolation mechanism (F =3.6,P ＜ 0.05).Conclusions BPD patients would like to use more immature and middle defense mechanisms and less mature ones.Emotional,physical and sexual abuse from parents and other adult care takers have a correlation with immature defense mechanisms,which indicates the importance of care about parental rearing patterns and mental health of children.

Objective To establish a high quality genomic DNA preparation method from formalin fixed and paraffin embedded tissues (FFPET) by integrating previous DNA extraction methods. Methods We combined classical genomic DNA extraction methods and commercially available DNA affinity column, replaced the de-waxing by dimethylbenzene with water-bath, designed a fast and improved genomic DNA preparation method. We also extracted genomic DNA from paraffin embedded cervical cancer tissues, and checked the quality of DNA by agarose gel electrophoresis and polymerase chain reaction detection. Results The improved genomic DNA extraction method combined the advantages of the water-bath de-waxing and DNA affinity column, making it possible to get high quality genomic DNA from paraffin embedded cervical cancer tissues, and especially efficient to recover genomic DNA fragments larger than 20 kb. Conclusion The improved DNA extraction method is fast and convenient to recover high quality genomic DNA from paraffin embedded tissues.

Objective To investigate the effect of high frequency stimulation of bilateral nucleus accumbens on relapse behaviors in morphine-dependent rats.Methods Twenty adult SD rats were employed in the experiment.Through stereotactic operation,outer electrode cannula was implanted into rats' bilateral nucleus accumbens.After 5 days of rest,the morphine-dependent rat model with conditioned place preference (CCP) was established through intraperitoneal morphine injection (10 mg/kg).After acquisition of CPP,normal saline was replaced with morphine for CPP extinction training.CPP test was used to exam the effect of extinction.The rats,after being randomly divided into experimental group (morphine+DBS) and control group (morphine+sham DBS),were electrically stimulated using modified DBS circuits.Rats in the experimental group were given high frequency electrical stimulation while the control group was sham stimulation.After consecutive stimulation for 7 days,rats in the two groups were given small dose of morphine (3 mg/kg)to trigger relapse.Results (1) The CPP score increased after the establishment of rat models compared with pre-establishment of the rat models((616.2±74.7) s vs (353.9±84.3) s,P＜0.01).(2) The CPP score after extinction training decreased compared with pre-conditioned CPP score ((456.4± 148.8) s vs (353.9±84.3) s),P=0.0847) and had no statistical difference compared with post-conditioned CPP score ((456.4±148.8) s vs (616.2± 74.7) s,P=0.0219).(3) When the relapse was induced by small doses of morphine within 24h after the last stimulation,the CPP score of the experimental group decreased compared with the CPP score of control group ((330.1 ±212.6) s vs (684.2±230.2)s,P=0.0029),and the relapse was restrained.Conclusion High frequency DBS of bilateral nucleus accumbens can attenuate relapse behavior in rats

Objective To investigate the influence of deep brain stimulation (DBS) at high frequency to the bilateral nucleus accumbens on morphine-induced conditioned place preference (CPP) and relapse behaviors during extinction phase in rats. Methods Twenty adult SD rats were employed in the experiment. Through stereotactic operation, outer electrode cannula was implanted into rats' bilateral nucleus accumbens. After 5 days of rest, the morphine-dependent rat model with CPP was established through intraperitoneal morphine injection (10 mg/kg). The rats, after being randomly divided into experimental group (morphine+DBS) and control group (morphine+sham DBS), were electrically stimulated using DBS circuits. Rats in the experimental group were given high frequency electrical stimulations while the control group was given sham stimulation. The CPP score of the two groups was recorded the day after stimulation until successful extinction and then the extinction time was compared between the two groups. After successful extinction the rats were given small dose of morphine to trigger relapse within 24 hours, and the CPP score was recorded and compared between the two groups.Results Compared with the control group (six days), the experimental group (26 days) had a longer extinction time. After relapse, the retention time within the drug-paired chamber of the experimental group was (357.01±192.72) s, obviously shorter than that of the control group ((704.91±181.35) s;t=2.370, P=0.034 6). Conclusion High frequency DBS to rats' bilateral nucleus accumbens can prolong extinction time but inhibit relapse behavior.