ObjectiveIn nature, objects cast shadows due to illumination, forming the basis for stereoscopic perception. Birds need to adapt to changes in lighting (meaning they can recognize stereoscopic shapes even when shadows look different) to accurately perceive different three-dimensional forms. However, how neurons in the key visual brain area in birds handle these lighting changes remains largely unreported. In this study, pigeons (Columba livia) were used as subjects to investigate how neurons in pigeon’s ventrolateral mesopallium (MVL) represent stereoscopic shapes consistently, regardless of changes in lighting. MethodsVisual cognitive training combined with neuronal recording was employed. Pigeons were first trained to discriminate different stereoscopic shapes (concave/convex). We then tested whether and how light luminance angle and surface appearance of the stereoscopic shapes affect their recognition accuracy, and further verify whether the results rely on specify luminance color. Simultaneously, neuronal firing activity of neurons was recorded with multiple electrode array implanted from the MVL during the presentation of difference shapes. The response was finally analyzed how selectively they responded to different stereoscopic shapes and whether their selectivity was affected by the changes of luminance condition (like lighting angle) or surface look. Support vector machine (SVM) models were trained on neuronal population responses recorded under one condition (light luminance angle of 45°) and used to decode responses under other conditions (light luminance angle of 135°, 225°, 315°) to verify the invariance of responses to different luminance conditions. ResultsBehavioral results from 6 pigeons consistently showed that the pigeons could reliably identify the core 3D shape (over 80% accuracy), and this ability wasn’t affected by changes in light angle or surface appearance. Statistical analysis of 88 recorded neurons from 6 pigeons revealed that 83% (73/88) showed strong selectivity for specific 3D shapes (selectivity index>0.3), and responses to convex shapes were consistently stronger than to concave shapes. These shape-selective responses remained stable across changes in light angle and surface appearance. Neural patterns were consistent under both blue and orange lighting. The decoding accuracy achieves above 70%, suggesting stable responses under different conditions (e.g., different lighting angles or surface appearance). ConclusionNeurons in the pigeon MVL maintain a consistent neural encoding pattern for different stereoscopic shapes, unaffected by illumination or surface appearance. This ensures stable object recognition by pigeons in changing visual environments. Our findings provide new physiological evidence for understanding how birds achieve stable perception (“invariant neural representations”) while coping with variations in the visual field.

Intermittent theta burst stimulation (iTBS), a time-saving and cost-effective repetitive transcranial magnetic stimulation regime, has been shown to improve cognition in patients with Alzheimer's disease (AD). However, the specific mechanism underlying iTBS-induced cognitive enhancement remains unknown. Previous studies suggested that mitochondrial functions are modulated by magnetic stimulation. Here, we showed that iTBS upregulates the expression of iron-sulfur cluster assembly 1 (ISCA1, an essential regulatory factor for mitochondrial respiration) in the brain of APP/PS1 mice. In vivo and in vitro studies revealed that iTBS modulates mitochondrial iron-sulfur cluster assembly to facilitate mitochondrial respiration and function, which is required for ISCA1. Moreover, iTBS rescues cognitive decline and attenuates AD-type pathologies in APP/PS1 mice. The present study uncovers a novel mechanism by which iTBS modulates mitochondrial respiration and function via ISCA1-mediated iron-sulfur cluster assembly to alleviate cognitive impairments and pathologies in AD. We provide the mechanistic target of iTBS that warrants its therapeutic potential for AD patients.
Humans ; Mice ; Animals ; Transcranial Magnetic Stimulation ; Alzheimer Disease/therapy* ; Cognitive Dysfunction/therapy* ; Cognition ; Sulfur ; Iron ; Iron-Sulfur Proteins ; Mitochondrial Proteins

Objective To study the effect and mechanism of action of Yi Sui Sheng Xue Fang(YSSX)in ameliorating chemotherapy-induced renal injury in mice through The Kelch-like ECH-associated protein 1(KEAP1)/Nuclear factor erythroid-derived 2-like 2(NRF2)signalling pathway.Methods A mouse kidney injury model was induced by intraperitoneal injection of carboplatin(40 mg·kg-1).C57BL/6 mice were randomly divided into blank group(0.9％NaCl),model group(kidney injury model)and experimental-L,experimental-M,experimental-H groups(0.53,1.05 and 2.10 g·kg-1·d-1 YSSX by gavage for 7 d).Keap1 and Nrf2 were determined by Western blot;superoxide dismutase(SOD)and malondialdehyde(MDA)activities were determined by spectrophotometry.Results The protein expression levels of Keap1 in blank group,model group and experimental-L,experimental-M,experimental-H groups were 0.26±0.02,0.64±0.03,0.59±0.01,0.45±0.05 and 0.34±0.02;the protein expression levels of Nrf2 were 0.69±0.06,0.35±0.01,0.36±0.01,0.48±0.02 and 0.56±0.01;the enzyme activities of catalase(CAT)were(572.49±912.92),(334.60±4.92),(402.76±9.80),(475.35±5.21)and(493.00±12.03)U·mg-1;glutathione(GSH)were(2.79±0.06),(0.51±0.01),(0.59±0.07),(1.29±0.04)and(1.70±0.08)μmol·L1;SOD were(477.00±4.32),(260.67±6.13),(272.67±2.87),(386.33±3.68)and(395.00±12.25)U·mL-1;MDA were(3.89±0.02),(7.32±0.03),(6.94±0.14),(4.60±0.01)and(4.34±0.02)nmol·mg prot-1.The differences of the above indexes in the model group compared with the blank group were statistically significant(P＜0.01,P＜0.001);the differences of the above indexes in experimental-M,experimental-H groups compared withe model group were statistically significant(P＜0.01,P＜0.001).Conclusion YSSX can activate Keap1/Nrf2 signaling pathway and regulate the oxidative stress state of the organism,thus improving the renal injury caused by chemotherapy in mice.

Objective To investigate the impact of emodin(EM)on vascular endothelial cell injury in rats with diabetes macroangiopathy by regulating hypoxia inducible factor-1α(HIF-1α)/vascular endothelial growth factor(VEGF)signaling pathway.Methods SD rats were divided into blank group and modeling group,the rats in the modeling group were fed with high fat and high sugar combined with N-nitro-L-arginine methyl ester to build the diabetes macroangiopathy model,and the blank group was fed with ordinary diet.The vascular endothelial cells successfully isolated from the thoracic aorta of rats in blank group and modeling group were named control group and model group,respectively.The vascular endothelial cells in the modeling group were divided into model group,dimethyloxallyl glycine(DMOG)group(10 μmol·L-1DMOG),combined group(80 mg·L-1EM+10 μmol·L-1 DMOG)and experimental-L,-M,-H groups(20,40,80 mg·L-1 EM).The apoptosis of rat vascular endothelial cells was detected by flow cytometry;Western blot was applied to detect the expression of HIF-1αand VEGF proteins in rat vascular endothelial cells.Results The apoptosis rates of vascular endothelial cells in experimental-M,-H groups,DMOG group,combined group,model group and control group were(10.18±0.36)％,(6.28±0.20)％,(24.96±1.18)％,(12.36±0.49)％,(18.76±0.68)％and(4.59±0.26)％;HIF-1α protein levels were 0.96±0.07,0.78±0.06,2.03±0.12,1.05±0.13,1.58±0.12 and 0.69±0.05;VEGF protein levels were 0.59±0.05,0.23±0.02,0.98±0.06,0.63±0.04,0.86±0.07 and 0.11±0.01.The above indexes in the model group were compared with the control,DMOG,experimental-M and experimental-H groups,and the above indexes in the combined group were compared with the experimental-H group,and the differences were statistically significant(all P＜0.05).Conclusion EM may inhibit HIF-1α/VEGF pathway to improve vascular endothelial cell injury in rats with diabetes macroangiopathy.

Traditional Chinese medicine can regulate the hypoxia-inducible factor-1α(HIF-1α)signalling pathway and slow down tumour progression mainly by inhibiting tumour angiogenesis,glycolysis,epithelial mesenchymal transition and other pathological processes.This paper,starting from HIF-1α and related factors,reviews its pathological mechanism in tumours and the research of traditional Chinese medicine interventions with the aim of providing theoretical references for the treatment of tumours with traditional Chinese medicine.

Objective To analyze the incidence and risk factors of hypothermia in elderly patients with malnutrition during proximal femoral nail antirotation(PFNA)internal fixation under general anesthesia.Methods A total of 139 elderly patients underwent PFNA internal fixation under general anesthesia were selected,and the nutritional status scores 1 day before surgery ranged from 0 to 11 points.Univariate and multivariate Logistic binary regression analysis was performed to analyze the related factors that may lead to intraoperative hypothermia.Results Among 139 elderly patients with preoperative nutritional scores of 0 to 11 points,79 cases(56.83%)developed intraoperative hypothermia.The results of univariate and multivariate Logistic binary regression analysis suggested that age≥75 years old,mini nutritional assessment short form(MNA-SF)nutritional score 0 to 7 points,BMI<18.5 kg/m2,duration of general anesthesia≥2 hours,intraoperative flushing fluid volume≥1 000 mL and intraoperative fluid volume≥1 000 mL were the risk factors for the occurrence of intraoperative hypothermia in elderly patients(OR>1,P<0.05).The use of warm blanket insulation was the protective factor against the occurrence of intraoperative hypothermia(OR<1,P<0.05).Conclusion The incidence of intraoperative hypothermia during PFNA internal fixation under general anesthesia in elderly patients with mainutrition before operation is high,and patients with poor nutritional status are more likely to develop intraoperative hypothermia.Patients with older age,poor nutritional status,lower BMI,longer duration of general anesthesia,and more intraoperative flushing fluid volume and intraoperative fluid volume are likely to lead to intraoperative hypothermia.The use of warm blanket can reduce the incidence of intraoperative hypothermia.

In black tea,theaflavins (TFs) are one important class of substances that determine sensory quality and have significant medicinal activities. In addition to the four kinds of common TFs,there may be many other theaflavin analogues (TFAs) with similar chemical structures in tea,but the study on them is very limited. Based on the characteristic sub-structure,mass spectrometry (MS) and MS/MS information,a method for screening and annotation of TFAs from the complex ultra high performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS) data was proposed in this work. By analyzing the oxidation and polymerization process of a few TFs,the theoretical reaction model of TFs were summarized,which was used to calculate the precursor ion values of potential TFAs. Meanwhile,the diagnostic fragmentation ions and neutral loss of TFAs according to the fragmentation pathways obtained from chemical standards or documented in literatures were summarized. As a result,36 kinds of compounds were successfully annotated based on the calculated precursor ion values and the MS fragmentation patterns,among which 6 kinds of compounds were reported for the first time in tea. In vitro synthesis experiments were carried out to verified the annotation results. Based on the results of quantitation of 36 kinds of TFAs,a partial least squares-discriminant analysis model was used to investigate the changes of these components during black tea manufacturing. The results indicated that these novel TFAs could be used to effectively distinguish the black tea samples before and after fermentation.

Background and aim:Hepatic ischemia-reperfusion injury(IRI)is a significant challenge in liver trans-plantation,trauma,hypovolemic shock,and hepatectomy,with limited effective interventions available.This study aimed to investigate the role of leukocyte cell-derived chemotaxin 2(LECT2)in hepatic IRI and assess the therapeutic potential of Lect2-short hairpin RNA(shRNA)delivered through adeno-associated virus(AAV)vectors. Materials and methods:This study analyzed human liver and serum samples from five patients under-going the Pringle maneuver.Lect2-knockout and C57BL/6J mice were used.Hepatic IRI was induced by clamping the hepatic pedicle.Treatments included recombinant human LECT2(rLECT2)and AAV-Lect2-shRNA.LECT2 expression levels and serum biomarkers including alanine aminotransferase(ALT),aspartate aminotransferase(AST),creatinine,and blood urea nitrogen(BUN)were measured.Histological analysis of liver necrosis and quantitative reverse-transcription polymerase chain reaction were performed. Results:Serum and liver LECT2 levels were elevated during hepatic IRI.Serum LECT2 protein and mRNA levels increased post reperfusion.Lect2-knockout mice had reduced weight loss;hepatic necrosis;and serum ALT,AST,creatinine,and BUN levels.rLECT2 treatment exacerbated weight loss,hepatic necrosis,and serum biomarkers(ALT,AST,creatinine,and BUN).AAV-Lect2-shRNA treatment significantly reduced weight loss,hepatic necrosis,and serum biomarkers(ALT,AST,creatinine,and BUN),indicating thera-peutic potential. Conclusions:Elevated LECT2 levels during hepatic IRI increased liver damage.Genetic knockout or shRNA-mediated knockdown of Lect2 reduced liver damage,indicating its therapeutic potential.AAV-mediated Lect2-shRNA delivery mitigated hepatic IRI,offering a potential new treatment strategy to enhance clinical outcomes for patients undergoing liver-related surgeries or trauma.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To investigate the efficacy of endoscopic Delta large channel unilateral laminotomy for bilateral decompression(ULBD)in the treatment of lumbar spinal stenosis(LSS),and the postoperative complications was analyzed.Methods A total of 100 patients with LSS in our hospital from January 2021 to February 2023 were selected and divided into the control group and the observation group according to random number table method,with 50 cases in each group.Patient in the control group were treated with bilateral or unilateral decompression through the median incision adjacent to the lateral spinous process,and patients in the observation group were treated with endoscopic Delta large channel ULBD.The visual analogue scale(VAS)scores,Japanese Orthopaedic Association(JOA)scores,Oswestry disability index(ODI)scores before surgery and 1 month,3 months,6 months after surgery,as well as clinical efficacy and incidence of postoperative complications of patients between the two groups were compared.Results Compared with preoperative results,the VAS scores of leg pain and low back pain and ODI scores of patients 1 month,3 months and 6 months after surgery in both groups were significantly lower(P<0.05),and JOA scores were significantly higher(P<0.05).Moreover,compared with the control group,the VAS scores of leg pain and low back pain and ODI scores of patients 1 month,3 months and 6 months after surgery in the observation group were lower(P<0.05),the JOA scores were higher(P<0.05).The total effective rate in the observation group was 98.00%,which was higher than 72.00%in the control group(P<0.05).The incidence of postoperative complications in the observation group was 4.00%,which was lower than 24.00%in the control group(P<0.05).Conclusion Endoscopic Delta large channel ULBD in the treatment of LSS can effectively reduce postopera-tive leg pain and low back pain,improve lumbar function,improve clinical therapeutic effect,and reduce postoperative complications.