Objective Accumulating evidence has demonstrated that the sub-anesthetic dose of ketamine exerts rapid and ro-bust antidepressant-like effects though its action mechanisms are not yet fully understood .The aim of this study was to investigate the role of gamma-aminobutyric acid ( GABA) in the antidepressant effects of ketamine . Methods Thirty-two male Wistar rats were e-qually randomized into four groups: saline, ketamine, GABA, and GABA+ketamine.All the animals were implanted with a guide cannula into the lateral ventricle and on the eighth day after operation subjected to a 15 min forced swimming test (FST) for the estab-lishment of a depression model .At 24 h after modeling , the rats of the saline and ketamine groups were treated intracerebroventricularly with 2μL isotonic saline solution, and those of the GABA and GABA +ketamine groups with 50μg (2μL) GABA, followed by intrap-eritoneal administration of 1 mL saline in the former two groups and 10 mg/kg (1 mL) ketamine in the latter two groups 10 min later.At 30 min after treatment , the open field test ( OFT) was carried out for crossing and rearing scores and a 6-min FST was performed to re-cord the immobility time in the last 5 minutes.The content of GABA in the prefrontal cortex of the rats was measured following behav -ioral tests. Results The immobility time was significantly decreased in the ketamine group ([107.5 ±21.2]sec) as compared with the saline, GABA, and GABA+ketamine groups ([167.2 ±22.1], [159.8 ±17.5], and [143.8 ±22.1]sec) (P<0.05), with no significant difference between the GABA and GABA +ketamine groups (P>0.05).The level of GABA in the prefrontal cortex was remarkably lower in the ketamine group ([12.4 ±3.4]ng/mg prot) than in the saline, GABA, and GABA+ketamine groups ([23.3 ± 6.3], [27.3 ±5.7], and [18.0 ±5.4]ng/mg prot) (P<0.05), but markedly higher in the GABA than in the GABA +ketamine group (P<0.05).OFT scores exhibited no significant difference in the lo-comotor activity among the four groups of rats ( P >0.05 ). Conclusion The antidepressant effects of ketamine are related to the decreased GABA level in the prefrontal cortex in rats receiving FST .

Objective To compare the diagnostic value of shear wave elastography and 18F-FDG PET/CT imaging in diagnosis of thyroid microcarcinoma.Methods Shear wave elastography and 18F-FDG PET/CT data of patients with thyroid nodules confirmed by pathology were analyzed retrospectively.The sensitivity,specificity,accuracy,positive and negative predictive value of the two methods in diagnosis of malignant thyroid micronodules were compared.Results In all of the 48 micronodules,37 were malignant,11 were benign.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of shear wave elastography and 18F-FDG PET/CT were 91.89％ (34/37),81.82％ (9/11),89.58％ (43/48),94.44％ (34/36),75.00％ (9/12) and 29.73％ (11/37),72.73％ (8/11),39.58％ (19/48),78.57％ (11/ 14),23.53％ (8/34),respectively.The sensitivity,accuracy and negative predictive value between the two methods had statistical difference (all P＜0.05),and the specificity and positive predictive value between the two methods had no statistical difference (both P＞0.05).Conclusion Compared to 18F FDG PET/CT imaging,the diagnositic value of shear wave elastography in diagnosis of thyroid microcarcinoma has obvious advantages.

Objective To compare the diagnostic value of ultrasound,thyroglobulin measurement in fine-needle aspiration biopsy(FNA-Tg),and their combination in the diagnosis of cervical lymph node metastasis in papillary thyroid carcinoma(PTC).Methods The clini-cal data of 130 patients(144 lymph nodes in total)with PTC in Tangshan Gongren Hospital from January 2017 to March 2023 were retro-spectively analyzed.Patients were divided into metastatic and non-metastatic groups according to the pathological findings of the cervical lymph nodes.The ultrasonic characteristics,serum Tg,and eluate Tg levels were compared between the two groups.The diagnostic efficacy of ultrasound,FNA-Tg,and the combination for cervical lymph node metastasis was assessed using the receiver operating characteristic(ROC)curve.Results Among 144 cervical lymph nodes,64 comprised the metastatic group and 80 comprised the non-metastatic group.Compared with the non-metastatic group,the lymph nodes in the metastatic group had indistinct cortical-medullary demarcation,uneven echogenicity,cystic changes,microcalcifications,and abnormal blood flow,and the differences were statistically significant(all P＜0.05);however,there was no statistically significant difference between the two groups in transverse to longitudinal ratios and whether the margins were clear(all P＞0.05).Serum Tg in the metastatic and non-metastatic groups was 19.5(1.9-70.7)ng/mL and 20.4(8.9-38.3)ng/mL,respectively,and the difference between the two groups was not statistically significant(P＞0.05);eluate Tg in the metastatic and non-metastatic groups was 500.0(49.4-500.0)ng/mL and 2.4(0.6-6.5)ng/mL,and the difference between the two groups was statisti-cally significant(P＜0.05),with an optimal FNA-Tg critical value of 11.7 ng/mL.FNA-Tg diagnosed cervical lymph node metastasis with the highest specificity,accuracy,and positive predictive value,whereas the combination of ultrasound and FNA-Tg diagnosed cervical lymph node metastasis with the highest sensitivity and negative predictive value.Conclusion Ultrasound manifestations of PTC cer-vical meta-static lymph nodes include poorly demarcated corticomedullary stroma,uneven echogenicity accompanied by cystic changes,microcalcifications,and abnormal blood flow and have high diagnostic efficacy for PTC metastatic lymph nodes.When PTC cervical lymph node abnormalities are suspected on ultrasound,further FNA-Tg should be performed.The combination of ultrasound with FNA-Tg could improve the diagnostic efficacy of PTC cervical lymph node metastasis.