Use of Ultra-Short Echo Time MRI to Improve Temporal Bone Imaging.

OBJECTIVE: The short T2 nature of cortical bone causes it to appear similar to air on MR, forcing clinicians to rely on computed tomography imaging, with its attendant ionizing radiation exposure, to define temporal bone structures. Through the use of novel MR sequences with ultra-short echo times (UTE), short T2 structures are now able to be visualized, allowing for improved understanding of anatomical relationships. METHODS: Eight patients (50% female) undergoing MR imaging of the skull base for diagnostic purposes (62.5% for vestibular schwannoma surveillance) at a tertiary care center were enrolled to evaluate the safety and efficacy of UTE imaging. CT scans were completed in 37.5% of the patients as part of their workup and used for comparison purposes. The repetition time, short echo time, and long echo time for the UTE sequence were 11, 0.032, and 2.2 msec, respectively. RESULTS: The protocol added 6 min to the total scanning time, and all patients tolerated the sequence without issue. The ossicles, mastoid air cells, antrum, and epitympanum were able to be seen and had a high Dice similarity coefficient when compared to CT (>0.5). UTE allowed for clear delineation of all segments of the facial nerve with a signal-to-noise ratio of 35 (although the BRAVO sequences had a superior ratio of 140). Vestibular schwannomas were able to be distinguished from normal brain parenchyma. CONCLUSIONS: UTE is safe and effective for visualizing anatomic structures not normally seen on traditional MRI, potentially allowing for improved surgical planning in patients. LEVEL OF EVIDENCE: III Laryngoscope, 2024.

[Efficacy and safety of early cannulation arteriovenous grafts for hemodialysis].

A total of 309 (138 males and 171 females) end-stage renal disease patients who underwent implantation of early cannulation arteriovenous grafts (Acuseal) for hemodialysis in Nanfang Hospital, Southern Medical University between December 2016 and May 2021 were retrospectively included. The age of patients was (61.5±10.3) years. There were 244 patients (119 males and 125 females) who received regular follow-up. During the follow-up period, 24 patients died. Perioperative complications included graft infection (4.5%, 11/244), hematoma (4.5%, 11/244) and steal syndrome (4.1%, 10/244). No seroma or anastomotic rupture occurred. The rates of the first postoperative puncture time within 24 h, 48 h and 72 h after implantation were 42.2%(103/244), 32.4% (79/244) and 16.4% (40/244), respectively. The Kaplan-Meier survival analysis showed that the primary patency rates at 6 months and 12 months were 66.5% and 48.4%, respectively, and the secondary patency rates at 6 months and 12 months were 96.7% and 91.8%, respectively. The current study indicates that the Acuseal graft is safe for vascular access in patients requiring hemodialysis, with satisfactory patency and acceptable complication rates at 1-year follow-up.

[Clinicopathological and genetic characteristics of common lymphatic malformations in superficial soft tissues].

Objective: To investigate the clinicopathological features, classification, and genetic characteristics of common lymphatic malformation (CLM) in superficial soft tissue. Methods: A retrospective study of 110 patients with the diagnosis of CLM at the Henan Province People's Hospital, China from August 2019 to August 2022 was performed. The clinicopathological features, relevant immunohistochemical (IHC) staining results, and fluorescence quantitative PCR of PIK3CA mutation were analyzed, and patients were followed up. Results: Among the 110 CLM patients, there were 53 males and 57 females; 65 cases (65/110, 59.1%) were first detected when the patients were≤2 years old. The most common location was the head and neck in 41 cases (41/110, 37.3%). Clinically, 102 cases (102/110, 92.7%) were solitary, 83 cases (83/110, 75.5%) were skin-colored, 69 cases (69/110, 62.7%) had indistinct borders, and 10 cases (10/110, 9.1%) had diffuse and severe macroscopic manifestations. There were 52 macrocystic type (52/110, 47.3%), 23 microcystic type (23/110, 20.9%), and 35 combined type (35/110, 31.8%). The macrocystic CLM presented as soft, translucent masses with large cystic cavities on the cut surface, and histologically they were composed of large, irregularly dilated channels that were thicker with irregular smooth muscle and lymphocytic infiltration. Microcystic CLM showed wartlike projections or translucent blisters on the skin, with small honeycomb structures on the cut surface, and histologically consisted of round or angular dilated small lymphatic vessels with little or no smooth muscle. The combined CLM had both macrocystic and microcystic morphologies. IHC staining showed that the lymphatic endothelial cells were positive for LYVE-1, D2-40, PROX1, CD31, and VEGFR3 but negative for CD34; in the macrocystic and combined CLM vessel walls were positive for SMA. Eight of 13 CLM had PIK3CA mutation. All patients were followed up, and 24 (24/110, 21.8%) had relapses, which more frequently occurred in combined type, followed by microcystic type. Conclusions: CLM is a congenital vascular malformation composed of dilated, abnormal lymphatic channels, with PIK3CA mutation. There are significant differences in clinicopathological characteristics among the different types. Since microcystic and combined CLM are prone to recurrence, accurate pathological subtyping is necessary to guide treatment and to predict prognosis.

[Glomuvenous malformation: a clinicopathological analysis of 31 cases].

Objective: To investigate the clinicopathological features of glomuvenous malformation (GVM). Methods: Thirty-one cases of GVM diagnosed at the Henan Provincial People's Hospital from January 2011 to December 2021 were collected. Their clinical and pathological features were analyzed. The expression of relevant markers was examined using immunohistochemistry. The patients were also followed up. Results: There were 16 males and 15 females in this study, with an average age of 11 years (range, 1-52 years). The locations of the disease included 13 cases in the limbs (8 cases in the upper limbs, 5 cases in the lower limbs), 9 cases in the trunks, and 9 cases in the foot (toes or subungual area). Twenty-seven of the cases were solitary and 4 were multifocal. The lesions were characterized by blue-purple papules or plaques on the skin surface, which grew slowly. The lumps became larger and appeared to be conspicuous. Microscopically, GVM mainly involved the dermis and subcutaneous tissue, with an overall ill-defined border. There were scattered or clustered irregular dilated vein-like lumens, with thin walls and various sizes. A single or multiple layers of relatively uniform cubic/glomus cells were present at the abnormal wall, with scattered small nests of the glomus cells. The endothelial cells in the wall of abnormal lumen were flat or absent. Immunohistochemistry showed that glomus cells strongly expressed SMA, h-caldesmon, and collagen IV. Malformed vascular endothelial cells expressed CD31, CD34 and ERG. No postoperative recurrence was found in the 12 cases. Conclusions: GVM is an uncommon type of simple venous malformation in the superficial soft tissue and different from the classical glomus tumor. Morphologically, one or more layers of glomus cells grow around the dilated venous malformation-like lumen, which can be combined with common venous malformations.

[Prenatal genetic diagnosis of the fetuses with isolated corpus callosum abnormality].

Objective: To explore the application value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in prenatal diagnosis of isolated corpus callosum abnormality (CCA) fetus. Methods: Fetuses diagnosed with isolated CCA by ultrasound and MRI and receiving invasive prenatal diagnosis in Guangzhou Women and Children's Medical Center and Qingyuan People's Hospital from January 2010 to April 2021 were selected. Karyotype analysis and/or CMA [or copy number variation sequencing (CNV-seq)] were performed on all fetal samples, and WES was performed on fetal samples and their parents whose karyotype analysis and/or CMA (or CNV-seq) results were not abnormal. Results: Among 65 fetuses with isolated CCA, 38 cases underwent karyotype analysis, and 3 cases were detected with abnormal karyotypes, with a detection rate of 8% (3/38). A total of 49 fetuses with isolated CCA underwent CMA (or CNV-seq) detection, and 6 cases of pathogenic CNV were detected, the detection rate was 12% (6/49). Among them, the karyotype analysis results were abnormal, and the detection rate of further CMA detection was 1/1. The karyotype results were normal, and the detection rate of further CMA (or CNV-seq) detection was 14% (3/21). The detection rate of CMA as the first-line detection technique was 7% (2/27). A total of 25 fetuses with isolated CCA with negative results of karyotyping and/or CMA were tested by WES, and 9 cases (36%, 9/25) were detected with pathogenic genes. The gradient genetic diagnosis of chromosomal karyotyping, CMA and WES resulted in a definite genetic diagnosis of 26% (17/65) of isolated CCA fetuses. Conclusions: Prenatal genetic diagnosis of isolated CCA fetuses is of great clinical significance. The detection rate of CMA is higher than that of traditional karyotyping. CMA detection could be used as a first-line detection technique for fetuses with isolated CCA. WES could increase the pathogenicity detection rate of fetuses with isolated CCA when karyotype analysis and/or CMA test results are negative.

[MicroRNA-132 promotes atherosclerosis by inducing mitochondrial oxidative stressmediated ferroptosis].

OBJECTIVE: To explore the expression of microRNA-132 (miR-132) and its potential role in the development of atherosclerosis (AS). METHODS: Thirty AS samples and 30 samples of normal peripheral vessels were collected from atherosclerotic patients undergoing peripheral angiostomy in our hospital for detecting the expression level of miR-132 using RT-qPCR. The expression of miR-132 in human umbilical vein endothelial cells (HUVEC) was up-regulated by liposome transfection, and intracellular reactive oxygen species (ROS), localization relationship between ROS and mitochondria, functional changes of mitochondrial reactive oxygen superoxide species (mtROS), mitochondrial membrane potential (MMP) and opening of mitochondrial permeability transition pore (mPTP) were analyzed by flow cytometry and laser confocal microscopy. The activity of mitochondrial redox respiratory chain complex (type I, II, III, IV and V) in HUVECs was detected using ELISA, and the expression levels of key iron death proteins were detected with Western blotting. RESULTS: RT-qPCR results showed that miR-132 was significantly up-regulated in atherosclerotic plaques compared with normal vascular samples (P < 0.001). Compared with control HUVECs, HUVECs overexpressing miR-132 showed a significantly increased level of intracellular ROS (P < 0.001), and most of ROS was colocalized with mitochondria. HUVECs overexpressing miR-132 also showed significantly decreased MMP (P < 0.001) and obviously increased mtROS (P < 0.001) and opening of mPTP (P < 0.001), which led to mitochondrial REDOX respiratory chain stress disorder. The key iron death protein GPX4 was significantly down-regulated and the oxidized protein NOX4 was significantly increased in miR-132-overexpressing HUVECs (P < 0.001). CONCLUSION: MiR-132 promotes atherosclerosis by inducing mitochondrial oxidative stress-mediated ferroptosis, which may serve as a promising therapeutic target for AS.

Distinct Age-Specific Effects on Olfactory Associative Learning in C57BL/6 Substrains.

C57BL/6 is the most widely used mouse strain in the laboratories. Two substrains of C57BL/6, C57BL/6J (B6J), and C57BL/6N (B6N) are well-known backgrounds for genetic modification and have been shown difference in quite a few tests, including open field test, rotarod test, and Morris water maze. However, difference between these two substrains in olfaction-dependent behaviors remains unknown. Here, we used olfactory two-alternative choice task, which is modified to have two training stages, to evaluate animals' ability in instrumental learning and olfactory association. In the first (rule learning) stage, the mice were trained to use the operant chamber to collect water rewards. An odor cue was provided in the procedure, with no indication about reward locations. In the following (discrimination learning) stage, two odor cues were provided, with each indicating a specific water port. The animals were rewarded upon correct port choices following cue deliveries. We found that during young adulthood (7-10 weeks old), proportionally more B6J than B6N mice were able to pass rule learning (58.3% vs. 29.2%) and ultimately acquire this task (54.2% vs. 25%), with the two substrains showing similar pass rates in discrimination learning (92.9% vs. 85.7%). Surprisingly, at a more mature age (17 weeks old), this substrain difference disappeared. Mature B6N mice had a significant improvement in pass percentages of rule learning and overall task, whereas similar improvement was not observed in the B6J counterparts. Instead, mature B6J mice had an improved speed in rule learning and overall task. We further examined behavioral patterns of 8-week-old B6J and B6N mice in the olfactory habituation or dishabituation test. We observed normal olfactory habituation from subjects of both substrains, with the B6J mice exhibiting stronger investigative responses to newly presented odorants. These results reveal for the first time that B6J and B6N mice are different in acquisition processes of a behavioral task that requires instrumental learning and olfactory association, and that maturation appears to employ different effects on these two substrains during these processes. Furthermore, young adult B6J and B6N mice might be similar in olfactory habituation but different in the olfactory aspects of novelty seeking.

The Role of Mitochondrial KATP Channels in the Infarct-Reducing Effect of Normobaric Hypoxia.

We studied the role of KATP channels in the infarct-limiting effect of short-term normobaric hypoxia. Male Wistar rats were subjected to a 45-min coronary artery occlusion followed by a 120-min reperfusion. Normobaric hypoxia was simulated 30 min before coronary artery occlusion: 6 sessions of hypoxia (8% O2, 10 min) and reoxygenation (21% O2, 10 min). The following drugs were administered to rats: glibenclamide, 5-hydroxydecanoate, and HMR1098. It was found that normobaric hypoxia contributes to a decrease in myocardial infarct size by 36%. Preliminary administration of glibenclamide or 5-hydroxydecanoate eliminated the infarct-reducing effect of normobaric hypoxia. Activator of mitochondrial KATP channel diazoxide limited the infarct size. These findings suggest that mitochondrial KATP channels are involved into the cardioprotective effect of normobaric hypoxia.

[The influence of cachexia on the immunotherapy efficacy of Sintilimab for non-small cell lung cancer].

Objective: To investigate whether cachexia affects the treatment effect of immune checkpoint inhibitors for non-small cell lung cancer (NSCLC). Methods: The prognosis of 62 patients with advanced NSCLC who received anti-programmed cell death-1 (PD-1) in Henan Provincial People's Hospital from 2019 to 2021 were retrospectively analyzed. The cachexia was evaluated before and after the second course of immunotherapy. Kaplan-Meier and Log rank methods were used for survival analysis, Cox regression model was used for multivariate analysis, and Spearman's correlation analysis was used for correlation analysis. Results: After the second course of immunotherapy, psoas major muscle area (PMMA) values of the cachexia group and the control group were (14.10±4.09) and (11.66±3.22) cm(2) respectively, with statistics significance (P=0.001). The level of Prealbumin and body weight were correlated with cachexia (P<0.05). The 6-month and 1-year survival rates of 62 cases in the whole group were 58.6% and 42.5%, respectively. The progression-free survival (PFS) in the control group (7.6 months) was higher than that in the cachexia group (3.8 months, P=0.006). The PFS in patients with high expression of PD-L1 (7.1 months) was longer than that of patients with low expression (3.8 months, P=0.009). The overall survival (OS) in the cachexia group (6.3 months) was lower than that in the control group (18.2 months, P=0.006). The OS in patients with high expression of PD-L1 (14.5 months) was longer than that of patients with low expression (1 months, P=0.038). The level of Prealbumin, the level of PD-L1 expression and the change rate of PMMA were related to the OS of the patients (P<0.05). The level of Prealbumin and the change rate of PMMA were the independent influencing factors of the OS (P<0.05). The PMMA and the level of Prealbumin were negatively correlated (r=-0.003 8, P<0.05). Conclusion: Cachexia has a negative impact on the outcomes of patients who received anti-PD-1 immune checkpoint inhibitor therapy.

[Analysis of families with fetal congenital abnormalities but negative prenatal diagnosis by whole exome sequencing].

Objective: To evaluate the value of whole exome sequencing (WES) in prenatal clinical application. Methods: A total of 1 152 cases of congenital abnormal [including structural malformation, nuchal translucency (NT) thickening and intrauterine growth restriction] with traditional prenatal diagnosis [including G-band karyotype analysis and chromosome microarray analysis (CMA)] negative were analyzed. The congenital abnormal fetuses were divided into retrospective group and prospective group according to the time of WES detection, that is whether the pregnancy termination or not. According to the specific location of fetal malformation and their family history, the cohort was divided into subgroups. The clinical prognosis of all fetuses were followed up, and the effect of WES test results on pregnancy decision-making and clinical intervention were analyzed. According to the follow-up results, the data of fetuses with new phenotypes in the third trimester or after birth were re-analyzed. Results: Among 1 152 families who received WES, 5 families were excluded because of nonbiological parents. Among the remaining 1 147 families, 152 fetuses obtained positive diagnosis (13.3%,152/1 147), including 74 fetuses in the retrospective group (16.1%,74/460) and 78 fetuses in the prospective group (11.4%,78/687). In fetuses with negative CMA and G-band karyotype analysis results but new phenotypes in the third trimester or after birth, the positive rate by WES data re-analysis was 4.9% (8/163). A total of 34 (21.3%, 34/160) fetuses were directly affected by the corresponding positive molecular diagnosis. Among 68 cases of live births with diagnostic variation grade 4, 29 cases (42.7%, 29/68) received appropriate medical intervention through rapid review of WES results. Conclusions: WES could increase the detection rate of abnormal fetuses with negative G-banding karyotype analysis and CMA by 13.3%. Prenatal WES could guide pregnancy decision-making and early clinical intervention. It might be an effective strategy to pay attention to the special follow-up of the third trimester and postnatal fetus and to re-analyze the WES data.

[Technology specification of bedside hypertonic saline-contrast electrical impedance tomography of lung perfusion and clinical application].

Bedside hypertonic saline-contrast electrical impedance tomography (EIT) method for lung perfusion evaluation has several advantages of bedside, simple, noninvasive and radiation-free. For a long time, EIT perfusion image of hypertonic saline was mostly limited to animal experiments, and related clinical research is in the ascendant. This technical specification for clinical application is reached based on our previous researches, review of literatures in this field. The purpose of this technical specification is to facilitate the unified and standardized use of hypertonic saline-contrast EIT technology for regional lung perfusion, to evaluate the safety and quality control of the technology, and to unify the results.

Specific contribution of neurons from the Dbx1 lineage to the piriform cortex.

The piriform cortex (PC) is a major cortical processing center for the sense of smell that receives direct inputs from the olfactory bulb. In mice, the PC consists of three neuronal layers, which are populated by cells with distinct developmental origins. One origin of PC neurons is the pool of Dbx1-expressing neural progenitors located in the ventral pallium at the pallial-subpallial boundary. Since the precise mechanisms of PC neuron development are largely unknown, we sought to define the distribution, timing of neurogenesis, morphology and projection patterns of PC neurons from the Dbx1 lineage. We found that Dbx1-lineage neurons are preferentially distributed in layer 2 and enriched in the ventral portion of the PC. Further, Dbx1 neurons are early-born neurons and contribute to most neuronal subtypes in the PC. Our data also revealed an enrichment of Dbx1-lineage neurons in the ventral anterior PC that project to the orbitofrontal cortex. These findings suggest a specific association between the developmental origin of PC neurons and their neuronal properties.

Forensic analysis of soman exposure using characteristic fragment ions from protein adducts.

The verification of exposure to nerve agents is a serious challenge, especially in cases of soman (GD) poisoning. Protein adducts are reliable biomarkers, that provide forensic information and evidence during incidents of terrorism or sporadic poisoning. Mass spectrometry, coupled with a proteomics approach, was established for the forensic analysis of GD-based protein adducts. The fragmentation pathways of GD-based protein adducts were investigated for the first time using electrospray ionization tandem mass spectrometry. Three abundant natural loss product ions, [M+2H-54]2+ (loss of two carbon cations), [M+2H-72]2+ (loss of tert-butyl and methyl moieties), and [M+2H-84]2+ (loss of the pinacolyl moieties), were observed in each of the GD-labeled adducts, and the product ions were independent of protein structure and exposure route. A unique mechanism for the formation of product ions involving GD-protein adducts is proposed here. These findings support the development of a simple and precise forensic analysis technique to rapidly verify GD poisoning using these three GD-related product ions.

AXIN2 gene silencing reduces apoptosis through regulating mitochondria-associated apoptosis signaling pathway and enhances proliferation of ESCs by modulating Wnt/ß-catenin signaling pathway.

OBJECTIVE: Embryonic stem cells (ESCs) mainly originate from totipotent cells in early-stage of mammalian embryo and could proliferate in a manner of un-limitation. This study aimed to investigate roles of Axin2 in proliferation of ESCs and explore the associated mechanisms. MATERIALS AND METHODS: Axis inhibition protein 2 (AXIN2) over-expression (LV5-AXIN2) and AXIN2 RNA interfere (LV3-AXIN2-RNAi) vectors were structured and transfected into H9 cells. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) was used to evaluate cell proliferative activity. Flow cytometry analysis was employed to measure apoptosis of H9 cells. AXIN2, ß-catenin, transcription factor 4 (TCF4), c-myc, c-jun and Cyclin D mRNA levels and protein expressions were determined using quantitative real-time PCR (qRT-PCR) and Western blotting assay. RESULTS: LV5-AXIN2 and LV3-AXIN2-RNAi were successfully structured with higher transfecting efficacy. AXIN2 gene silencing remarkably increased proliferative activity and AXIN2 treatment significantly induced apoptosis of H9 cells, comparing with blank vector group (p<0.05). AXIN2 gene silencing significantly enhanced B-cell lymphoma-2 (Bcl-2) expression and remarkably inhibited cleaved caspase-3 expression comparing to that in blank vector group (p<0.05). AXIN2-RNAi treatment significantly enhanced and AXIN2 over-expression significantly reduced ß-catenin and TCF4 expression, comparing to that in blank vector group (p<0.05). AXIN2 gene silence activated down-stream molecules of Wnt/ß-catenin signaling pathway, including c-jun, c-myc, and Cyclin D1 (p<0.05). CONCLUSIONS: AXIN2 gene silencing reduced apoptosis by regulating mitochondria-associated apoptosis signaling pathway and enhanced proliferation by modulating molecules in Wnt/ß-catenin signaling pathway. Therefore, targeting of aberrant apoptosis and AXIN2 might be a novel clinical strategy to inhibit aging and enhance self-renewal of ESCs.