ObjectiveTo explore the diagnostic value of resting-state functional magnetic resonance imaging (rs-fMRI) for mild cognitive impairment (MCI) stage of Alzheimer's disease (AD), and to investigate the changes in brain functional connectivity in default mode network (DMN) and medial temporal lobe (MTL) regions. MethodsLiteratures were retrieved from multiple databases including CNKI, PubMed, Medline, and Embase, etc. from January, 2020 to October, 2025, investigating the changes in functional connectivity of DMN and MTL in patients with MCI compared to health control (HC) using rs-fMRI. Two researchers independently screened and extracted the literatures and methodological quality was assessed using QUADAS-2. Review Manager 5.4 was used to perform a meta-analysis of neuroimaging indicators in MCI patients and HC subjects. Stata and SDM were utilized to summarize diagnostic efficacy and brain functional connectivity, calculating the over all sensitivity, specificity and summary receiver operating characteristic-area under the curve (SROC-AUC). Deeks funnel plots were drawn, literature weights were analyzed, and subgroup analyses were conducted. ResultsA total of ten literatures were ultimately included, involving 1 010 patients with MCI and 1 714 HC subjects. MCI patients showed decreased or abnormal blood oxygen level dependence signals in DMN, focusing on bilateral medial prefrontal cortex (mPFC) and posterior cingulate cortex. The SROC-AUC was 0.91. In MTL, there was a characteristic decrease of spontaneous neural functional connectivities between the hippocampus and other regions, reflecting the obstruction of information transmission from episodic memory to the central nodes. Abnormal functional connectivity in DMN and MTL resulted in compensatory resting-state functional connectivity enhancement in other subnetworks or local functional connections, such as frontoparietal network and the hippocampal-parietal network. Abnormal activation of mPFC suggested atrophy of the hippocampus or abnormal brain function. The decline in functional connectivity between DMN and MTL indicated impairment of memory and information processing in the early stage. ConclusionThe early functional decoupling between DMN and MTL is a crucial neural mechanism at the MCI stage of AD, providing important neuroimaging evidence for the early diagnosis of AD.

Objective:To investigate the clinical utility of 68Ga-labeled fibroblast activation protein inhibitor (FAPI) PET/CT in the detection of primary and metastatic gastric signet-ring cell carcinoma (GSRCC) and compared the results with those of 18F-FDG PET/CT. Methods:A total of 21 patients (10 males, 11 females, average age 52 years) with primary and metastatic GSRCC who underwent 68Ga-FAPI and 18F-FDG PET/CT at the First Affiliated Hospital of Xiamen University from June 2020 to May 2022 were retrospectively analyzed. Pathological results of surgery and (or) biopsy were used as the " gold standard" for final diagnosis. In cases whose surgery or tissue biopsies were not available, clinical and radiographic follow-up results were used as the reference standards. Wilcoxon signed-rank test was used to compare the SUV max of 18F-FDG and 68Ga-FAPI. McNemar χ2 test was used to compare the detection rate between 18F-FDG and 68Ga-FAPI PET/CT. Results:68Ga-FAPI PET/CT showed higher SUV max than 18F-FDG in primary tumors (5.3(2.4, 15.7) vs 2.4(1.8, 2.5); z=2.31, P=0.021), local recurrences (7.8(6.0, 8.9) vs 2.4(1.9, 3.4); z=2.20, P=0.028), lymph nodes metastases (7.7(4.5, 12.2) vs 2.4(1.9, 3.6); z=6.01, P<0.001) and bone/visceral metastases (6.7(5.3, 11.1) vs 2.4(2.0, 3.4); z=11.36, P<0.001). Regarding diagnostic accuracy, 68Ga-FAPI PET/CT showed higher sensitivities than 18F-FDG for primary tumors (7/9 vs 2/9; χ2=3.20, P=0.063) and local recurrences (7/7 vs 2/7; χ2=3.20, P=0.063). It also demonstrated higher lesion detection rates than 18F-FDG for suspicious lymph node metastases (86%(65/76) vs 32%(24/76); χ2=31.37, P<0.001) and bone/visceral metastases (99%(184/185) vs 39%(73/185); χ2=107.08, P<0.001). Conclusions:68Ga-FAPI PET/CT showed higher tumor uptake and lesion detection rate than 18F-FDG in the primary and metastatic GSRCC. 68Ga-FAPI PET/CT demonstrates good diagnostic performance for tumor detection, staging, and restaging of GSRCC, which is helpful to further guide clinical treatment strategy.

Objective To synthesize 18F-AlF-NOTA-G-TMTP1 and evaluate its potential for PET imaging on nude mice bearing high-metastatic potential hepatoma cells.Methods NOTA-G-TMTP1 was synthesized by the standard Fmoc-solid phase synthetic protocols and radiolabeled with 18F using NOTA-AlF chelation method.The nude mice models bearing low-metastatic potential HCC97L and high-metastatic potential HCCLM3 xenografts were established separately.The tumor-targeting characteristics of 18F-AlF-NOTA-G-TMTP1 were assessed by microPET/CT and biodistribution assay.Results NOTA-G-TMTP1 was labeled with 18F in one step with (25±6)％ labeling yield (n=5).The radiochemical purity of 18F-AlF-NOTA-G-TMTP1 was more than 95％ with a specific activity more than 11.1 GBq/μmol.The octanol/water partition coefficient (logP) for 18F-AlF-NOTA-G-TMTP1 was-3.166±0.022.The tumor to muscle ratios were 1.8± 0.4 and 4.7±0.2 at 35 min post injection for HCC97L and HCCLM3,respectively.The uptake of 18F-AlF-NOTA-G-TMTP1 in HCCLM3 tumor was inhibited (61.4％) by unlabeled G-TMTP1.Conclusion 18F-AlF-NOTA-G-TMTP1 has been successfully synthesized.It shows specific uptake by tumor induced by the high-metastatic potential hepatoma cells.

OBJECTIVETo investigate the correlation between arterial partial pressure of CO2 (PaCO2) and end expiratory tidal partial pressure of CO2 (Pet-CO2) in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery.

METHODSForty morbidly obese patients with a body mass index (BMI) between 35 and 50 kg/m(2) underwent laparoscopic gastric bypass surgery under general anesthesia. PaCO2 and Pet-CO2 were measured after intubation and before induction of pneumoperitoneum (T0), at 30 min (T1), 60 min (T2), and 120 min (T3) during pneumoperitoneum, and at 30 min (T4) and 60 min (T5) after deflation.

RESULTSAt each time point of measurement, Pet-CO2 was lower than PaCO2 in all the patients. PaCO2 and Pet-CO2 were positively correlated before, during, and after pneumoperitoneum (P<0.05). At a moderate pressure of CO2 pneumoperitoneum (16 mmHg), the level of correlation between PaCO2 and Pet-CO2 at T1, T2, and T3 differed from that before and after post-pneumoperitoneum.

CONCLUSIONSPaCO2 and Pet-CO2 are closely correlated during a moderate CO2 pneumoperitoneum in morbidly obese patients undergoing laparoscopic gastric bypass surgery.

Adult ; Anesthesia ; Arterial Pressure ; Blood Gas Analysis ; Carbon Dioxide ; blood ; Female ; Gastric Bypass ; Humans ; Laparoscopy ; Male ; Middle Aged ; Obesity, Morbid ; blood ; surgery ; Pneumoperitoneum, Artificial

Objective To develop a blood gas,acid-base imbalance analysis computer software to diagnose systematically,rapidly,accurately and automatically determine acid-base imbalance type,and evaluate the clinical application. Methods Using VBA programming language,a computer aided diagnostic software for the judgment of acid-base balance was developed. The clinical data of 220 patients admitted to the Second Affiliated Hospital of Guangzhou Medical University were retrospectively analyzed. The arterial blood gas〔pH value,HCO3-,arterial partial pressure of carbon dioxide(PaCO2)〕and electrolytes included data(Na+and Cl-)were collected. Data were entered into the software for acid-base imbalances judgment. At the same time the data generation was calculated manually by H-H compensation formula for determining the type of acid-base imbalance. The consistency of judgment results from software and manual calculation was evaluated,and the judgment time of two methods was compared. Results The clinical diagnosis of the types of acid-base imbalance for the 220 patients:65 cases were normal,90 cases with simple type,mixed type in 41 cases,and triplex type in 24 cases. The accuracy of the judgment results of the normal and triplex types from computer software compared with which were calculated manually was 100%,the accuracy of the simple type judgment was 98.9% and 78.0% for the mixed type,and the total accuracy was 95.5%. The Kappa value of judgment result from software and manual judgment was 0.935,P=0.000. It was demonstrated that the consistency was very good. The time for software to determine acid-base imbalances was significantly shorter than the manual judgment(seconds:18.14±3.80 vs. 43.79±23.86,t=7.466,P=0.000),so the method of software was much faster than the manual method. Conclusion Software judgment can replace manual judgment with the characteristics of rapid,accurate and convenient,can improve work efficiency and quality of clinical doctors and has great clinical application promotion value.

Objective To investigate the correlation between arterial partial pressure of CO2 (PaCO2) and end expiratory tidal partial pressure of CO2 (Pet-CO2) in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery. Methods Forty morbidly obese patients with a body mass index (BMI) between 35 and 50 kg/m2 underwent laparoscopic gastric bypass surgery under general anesthesia. PaCO2 and Pet-CO2 were measured after intubation and before induction of pneumoperitoneum (T0), at 30 min (T1), 60 min (T2), and 120 min (T3) during pneumoperitoneum, and at 30 min (T4) and 60 min (T5) after deflation. Results At each time point of measurement, Pet-CO2 was lower than PaCO2 in all the patients. PaCO2 and Pet-CO2 were positively correlated before, during, and after pneumoperitoneum (P<0.05). At a moderate pressure of CO2 pneumoperitoneum (16 mmHg), the level of correlation between PaCO2 and Pet-CO2 at T1, T2, and T3 differed from that before and after post- pneumoperitoneum. Conclusion PaCO2 and Pet- CO2 are closely correlated during a moderate CO2 pneumoperitoneum in morbidly obese patients undergoing laparoscopic gastric bypass surgery.

Objective To investigate the correlation between arterial partial pressure of CO2 (PaCO2) and end expiratory tidal partial pressure of CO2 (Pet-CO2) in morbidly obese patients during anesthesia for laparoscopic gastric bypass surgery. Methods Forty morbidly obese patients with a body mass index (BMI) between 35 and 50 kg/m2 underwent laparoscopic gastric bypass surgery under general anesthesia. PaCO2 and Pet-CO2 were measured after intubation and before induction of pneumoperitoneum (T0), at 30 min (T1), 60 min (T2), and 120 min (T3) during pneumoperitoneum, and at 30 min (T4) and 60 min (T5) after deflation. Results At each time point of measurement, Pet-CO2 was lower than PaCO2 in all the patients. PaCO2 and Pet-CO2 were positively correlated before, during, and after pneumoperitoneum (P<0.05). At a moderate pressure of CO2 pneumoperitoneum (16 mmHg), the level of correlation between PaCO2 and Pet-CO2 at T1, T2, and T3 differed from that before and after post- pneumoperitoneum. Conclusion PaCO2 and Pet- CO2 are closely correlated during a moderate CO2 pneumoperitoneum in morbidly obese patients undergoing laparoscopic gastric bypass surgery.