Going straight for the gut:gut-brain axis pathology and treatment of Parkinson's disease

This perspective focuses on the recent literature regarding the role of the gut-brain axis(GBA) in fecal microbiota transplantation(FMT) and stem cell therapy(SCT) in Parkinson's disease(PD).PD is the second most common neurodegenerative disease in the United States,yet therapies remain limited.Current research suggests that the GBA may play a role in the pathogenesis of PD.GBAbased FMT as well as SCT offer promising new avenues for PD treatment.Pro bing the interactions between FMT and SCT with the GBA may reveal novel therapeutics for PD.

Amyloid-beta pathology-induced nanoscale synaptic disruption:the case of the GABA_B-GIRK assembly

Alzheimer's disease (AD) is characterized by an imbalance between excitatory and inhibitory brain networks,leading to aberrant homeostatic synaptic plasticity.AD has progressively been recognized as syna ptopathy and syna ptic dysfunction has been identified as a key component of its pathogenesis (Schirinzi et al.,2020).Syna ptic dysfunction is believed to precede synapse loss,a primary biological correlate of cognitive decline in AD,inevita bly associated with neuronal death.

Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice

Plaques of amyloid-β(Aβ)and neurofibrillary tangles are the main pathological characteristics of Alzheimer’s disease(AD).However,some older adult people with AD pathological hallmarks can retain cognitive function.Unraveling the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic targets.Our hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels,which may underlie healthy cognitive performance in aged AD animals.Utilizing the Morris Water Maze test,we selected resilient(asymptomatic)and cognitively impaired aged Tg2576 mice.While the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups,western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant fraction.To further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice,we employed stereological and electron microscopic methods.Our findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic controls.Intriguingly,through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice,we uncovered differences in the subcellular localization of glutamate receptors.Specifically,the density of GluA1,GluA2/3,and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic controls.Notably,the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic mice.These subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play crucial roles in the mechanisms of cognitive resilience in Tg2576 mice.

Using MsfNet to Predict the ISUP Grade of Renal Clear Cell Carcinoma in Digital Pathology Images

Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment selection.This study presents a new deep network called Multi-scale Fusion Network(MsfNet),which aims to enhance the automatic ISUP grade of ccRCC with digital histopathology pathology images.The MsfNet overcomes the limitations of traditional ResNet50 by multi-scale information fusion and dynamic allocation of channel quantity.The model was trained and tested using 90 Hematoxylin and Eosin(H&E)stained whole slide images(WSIs),which were all cropped into 320×320-pixel patches at 40×magnification.MsfNet achieved a micro-averaged area under the curve(AUC)of 0.9807,a macro-averaged AUC of 0.9778 on the test dataset.The Gradient-weighted Class Activation Mapping(Grad-CAM)visually demonstrated MsfNet’s ability to distinguish and highlight abnormal areas more effectively than ResNet50.The t-Distributed Stochastic Neighbor Embedding(t-SNE)plot indicates our model can efficiently extract critical features from images,reducing the impact of noise and redundant information.The results suggest that MsfNet offers an accurate ISUP grade of ccRCC in digital images,emphasizing the potential of AI-assisted histopathological systems in clinical practice.

NLRP3-mediated autophagy dysfunction links gut microbiota dysbiosis to tau pathology in chronic sleep deprivation

Emerging evidence indicates that sleep deprivation(SD)can lead to Alzheimer’s disease(AD)-related pathological changes and cognitive decline.However,the underlying mechanisms remain obscure.In the present study,we identified the existence of a microbiota-gut-brain axis in cognitive deficits resulting from chronic SD and revealed a potential pathway by which gut microbiota affects cognitive functioning in chronic SD.Our findings demonstrated that chronic SD in mice not only led to cognitive decline but also induced gut microbiota dysbiosis,elevated NLRP3 inflammasome expression,GSK-3βactivation,autophagy dysfunction,and tau hyperphosphorylation in the hippocampus.Colonization with the“SD microbiota”replicated the pathological and behavioral abnormalities observed in chronic sleep-deprived mice.Remarkably,both the deletion of NLRP3 in NLRP3-/-mice and specific knockdown of NLRP3 in the hippocampus restored autophagic flux,suppressed tau hyperphosphorylation,and ameliorated cognitive deficits induced by chronic SD,while GSK-3βactivity was not regulated by the NLRP3 inflammasome in chronic SD.Notably,deletion of NLRP3 reversed NLRP3 inflammasome activation,autophagy deficits,and tau hyperphosphorylation induced by GSK-3βactivation in primary hippocampal neurons,suggesting that GSK-3β,as a regulator of NLRP3-mediated autophagy dysfunction,plays a significant role in promoting tau hyperphosphorylation.Thus,gut microbiota dysbiosis was identified as a contributor to chronic SD-induced tau pathology via NLRP3-mediated autophagy dysfunction,ultimately leading to cognitive deficits.Overall,these findings highlight GSK-3βas a regulator of NLRP3-mediated autophagy dysfunction,playing a critical role in promoting tau hyperphosphorylation.

Microvascular structural changes in esophageal squamous cell carcinoma pathology according to intrapapillary capillary loop types under magnifying endoscopy

BACKGROUND The intrapapillary capillary loop(IPCL)characteristics,visualized using magnifying endoscopy,are commonly assessed for preoperative evaluation of the infiltration depth of esophageal squamous cell carcinoma(ESCC).Japan Esophageal Society(JES)classification is the most widely used classification.Microvascular structural changes are evaluated by magnifying endoscopy for the presence or absence of each morphological factor:tortuosity,dilatation,irregular caliber,and different shapes.However,the pathological characteristics of IPCLs have not been thoroughly investigated,especially the microvascular structures corresponding to the deepest parts of the lesions'infiltration.AIM To investigate differences in pathological microvascular structures of ESCC,which correspond to the deepest parts of the lesions'infiltration.METHODS Patients with ESCC and precancerous lesions diagnosed at Peking University Third Hospital were enrolled between January 2019 and April 2023.Patients first underwent magnified endoscopic examination,followed by endoscopic submucosal dissection or surgical treatment.Pathological images were scanned using a threedimensional slice scanner,and the pathological structural differences in different types,according to the JES classification,were analyzed using nonparametric tests and t-tests.RESULTS The 35 lesions were divided into four groups according to the JES classification:A,B1,B2,and B3.Statistical analyses revealed significant differences(aP<0.05)in the short and long calibers,area,location,and density between types A and B.Notably,there were no significant differences in these parameters between types B1 and B2 and between types B2 and B3(P>0.05).However,significant differences in the short calibers,long calibers,and area of IPCL were observed between types B1 and B3(aP<0.05);no significant differences were found in the density or location(P>0.05).CONCLUSION Pathological structures of IPCLs in the deepest infiltrating regions differ among various IPCL types classified by the JES classification under magnifying endoscopy,especially between the types A and B.

A Multi-Task Deep Learning Framework for Simultaneous Detection of Thoracic Pathology through Image Classification

Thoracic diseases pose significant risks to an individual's chest health and are among the most perilous medical diseases. They can impact either one or both lungs, which leads to a severe impairment of a person’s ability to breathe normally. Some notable examples of such diseases encompass pneumonia, lung cancer, coronavirus disease 2019 (COVID-19), tuberculosis, and chronic obstructive pulmonary disease (COPD). Consequently, early and precise detection of these diseases is paramount during the diagnostic process. Traditionally, the primary methods employed for the detection involve the use of X-ray imaging or computed tomography (CT) scans. Nevertheless, due to the scarcity of proficient radiologists and the inherent similarities between these diseases, the accuracy of detection can be compromised, leading to imprecise or erroneous results. To address this challenge, scientists have turned to computer-based solutions, aiming for swift and accurate diagnoses. The primary objective of this study is to develop two machine learning models, utilizing single-task and multi-task learning frameworks, to enhance classification accuracy. Within the multi-task learning architecture, two principal approaches exist soft parameter sharing and hard parameter sharing. Consequently, this research adopts a multi-task deep learning approach that leverages CNNs to achieve improved classification performance for the specified tasks. These tasks, focusing on pneumonia and COVID-19, are processed and learned simultaneously within a multi-task model. To assess the effectiveness of the trained model, it is rigorously validated using three different real-world datasets for training and testing.

Expanding role and scope of artificial intelligence in the field of gastrointestinal pathology

Digital pathology(DP)and its subsidiaries including artificial intelligence(AI)are rapidly making inroads into the area of diagnostic anatomic pathology(AP)including gastrointestinal(GI)pathology.It is poised to revolutionize the field of diagnostic AP.Historically,AP has been slow to adopt digital technology,but this is changing rapidly,with many centers worldwide transitioning to DP.Coupled with advanced techniques of AI such as deep learning and machine learning,DP is likely to transform histopathology from a subjective field to an objective,efficient,and transparent discipline.AI is increasingly integrated into GI pathology,offering numerous advancements and improvements in overall diagnostic accuracy,efficiency,and patient care.Specifically,AI in GI pathology enhances diagnostic accuracy,streamlines workflows,provides predictive insights,integrates multimodal data,supports research,and aids in education and training,ultimately improving patient care and outcomes.This review summarized the latest developments in the role and scope of AI in AP with a focus on GI pathology.The main aim was to provide updates and create awareness among the pathology community.

Do tau-synaptic long-term depression interactions in the hippocampus play a pivotal role in the progression of Alzheimer’s disease?

Cognitive decline in Alzheimer’s disease correlates with the extent of tau pathology,in particular tau hyperphosphorylation that initially appears in the transentorhinal and related regions of the brain including the hippocampus.Recent evidence indicates that tau hyperphosphorylation caused by either amyloid-βor long-term depression,a form of synaptic weakening involved in learning and memory,share similar mechanisms.Studies from our group and others demonstrate that long-term depression-inducing low-frequency stimulation triggers tau phosphorylation at different residues in the hippocampus under different experimental conditions including aging.Conversely,certain forms of long-term depression at hippocampal glutamatergic synapses require endogenous tau,in particular,phosphorylation at residue Ser396.Elucidating the exact mechanisms of interaction between tau and long-term depression may help our understanding of the physiological and pathological functions of tau/tau(hyper)phosphorylation.We first summarize experimental evidence regarding tau-long-term depression interactions,followed by a discussion of possible mechanisms by which this interplay may influence the pathogenesis of Alzheimer’s disease.Finally,we conclude with some thoughts and perspectives on future research about these interactions.

Axial length,vitreoretinal pathology,and anterior chamber depth can predict postoperative refractive outcomes in phacovitrectomy/silicone oil removal

AIM:To evaluate the postoperative refractive prediction error(PE)and determine the factors that af fect the refractive outcomes of combined pars plana vitrectomy(PPV)or silicone oil removal(SOR)with cataract surgery.METHODS:The study is a retrospective,case-series study.Totally 301 eyes of 301 patients undergoing combined PPV/SOR with cataract surgery were enrolled.Eligible individuals were separated into four groups according to their preoperative diagnoses:silicone oil-filled eyes after PPV(group 1),epiretinal membrane(group 2),macular hole(group 3),and primary retinal detachment(RD;group 4).The variables af fecting postoperative refractive outcomes were analyzed,including age,gender,preoperative best-corrected visual acuity(BCVA),axial length(AL),keratometry average,anterior chamber depth(ACD),intraocular tamponade,and vitreoretinal pathology.The outcome measurements include the mean refractive PE and the proportions of eyes with a PE within±0.50 diopter(D)and±1.00 D.RESULTS:For all patients,the mean PE was-0.04±1.17 D,and 50.17%of patients(eyes)had a PE within±0.50 D.There was a significant difference in refractive outcomes among the four groups(P=0.028),with RD(group 4)showing the least favorable refractive outcome.In multivariate regression analysis,only AL,vitreoretinal pathology,and ACD were strongly associated with PE(all P<0.01).Univariate analysis revealed that longer eyes(AL>26 mm)and a deeper ACD were correlated with hyperopic PE,and shorter eyes(AL<26 mm)and a shallower ACD were correlated with myopic PE.CONCLUSION:RD patients have the least favorable refractive outcome.AL,vitreoretinal pathology,and ACD are strongly associated with PE in the combined surgery.These three factors affect refractive outcomes and thus can be used to predict a better postoperative refractive outcome in clinical practice.

Quantitative proteomic and phosphoproteomic analyses of the hippocampus reveal the involvement of NMDAR1 signaling in repetitive mild traumatic brain injury

The cumulative damage caused by repetitive mild traumatic brain injury can cause long-term neurodegeneration leading to cognitive impairment.This cognitive impairment is thought to result specifically from damage to the hippocampus.In this study,we detected cognitive impairment in mice 6 weeks after repetitive mild traumatic brain injury using the novel object recognition test and the Morris water maze test.Immunofluorescence staining showed that p-tau expression was increased in the hippocampus after repetitive mild traumatic brain injury.Golgi staining showed a significant decrease in the total density of neuronal dendritic spines in the hippocampus,as well as in the density of mature dendritic spines.To investigate the specific molecular mechanisms underlying cognitive impairment due to hippocampal damage,we performed proteomic and phosphoproteomic analyses of the hippocampus with and without repetitive mild traumatic brain injury.The differentially expressed proteins were mainly enriched in inflammation,immunity,and coagulation,suggesting that non-neuronal cells are involved in the pathological changes that occur in the hippocampus in the chronic stage after repetitive mild traumatic brain injury.In contrast,differentially expressed phosphorylated proteins were mainly enriched in pathways related to neuronal function and structure,which is more consistent with neurodegeneration.We identified N-methyl-D-aspartate receptor 1 as a hub molecule involved in the response to repetitive mild traumatic brain injury,and western blotting showed that,while N-methyl-D-aspartate receptor 1 expression was not altered in the hippocampus after repetitive mild traumatic brain injury,its phosphorylation level was significantly increased,which is consistent with the omics results.Administration of GRP78608,an N-methyl-D-aspartate receptor 1 antagonist,to the hippocampus markedly improved repetitive mild traumatic brain injury-induced cognitive impairment.In conclusion,our findings suggest that N-methyl-D-aspartate receptor 1 signaling in the hippocampus is involved in cognitive impairment in the chronic stage after repetitive mild traumatic brain injury and may be a potential target for intervention and treatment.

Aquaporin 5 in Alzheimer’s disease:a link between oral and brain pathology?

The involvement of aquaporins(AQPs)in the development of diseases has been widely described(Azad et al.,2021).AQP5 has been described in astrocytes changing after traumatic brain injuries(Chai et al.,2013),but the precise role of AQP5 in Alzheimer’s disease(AD)pathology is yet to be understood.We have recently reported that AQP5 expression changes during the development of AD(Antequera et al.,2022).The AQP5 expression in salivary glands is decreased in 6-month-old APP/PS1 mice and AD patients.This decrease in AQP5 expression could be involved in the mechanism of salivary gland dysfunction described in a previous study(Antequera et al.,2021).Now,we propose a new indirect role of AQP5 in the connection between infection-induced oral dysbiosis and AD(Sureda et al.,2020).Here,we suggest that the proinflammatory response induced by oral pathogen infection results in the downregulation of AQP5 contributing to the salivary gland secretory dysfunction.All these alterations destabilize the peripheral immune-inflammatory balance and exacerbate neuroinflammation and neurodegeneration leading to AD pathology.

SC-Net:A New U-Net Network for Hippocampus Segmentation

Neurological disorders like Alzheimer’s disease have a significant impact on the lives and health of the elderly as the aging population con-tinues to grow.Doctors can achieve effective prevention and treatment of Alzheimer’s disease according to the morphological volume of hippocam-pus.General segmentation techniques frequently fail to produce satisfactory results due to hippocampus’s small size,complex structure,and fuzzy edges.We develop a new SC-Net model using complete brain MRI images to achieve high-precision segmentation of hippocampal structures.The proposed network improves the accuracy of hippocampal structural segmentation by retaining the original location information of the hippocampus.Extensive experimental results demonstrate that the proposed SC-Net model is signif-icantly better than other models,and reaches a Dice similarity coefficient of 0.885 on Alzheimer’s Disease Neuroimaging Initiative(ADNI)dataset.

Effects of alendronate on bone mass and organ pathology in ovariectomized mice

Objective:To investigate the effect of alendronate on bone mass and organ pathology of ovariectomized mice.Methods:Thirty SPF grade C57 female mice were randomly divided into three groups(n=10):Sham operation group(Sham),ovariectomized group(OVX)and ovariectomized+alendronate group(ALN).The sodium alendronate was injected subcutaneously at 400μg/kg twice a week in the ALN group.The equal volume of normal saline was injected subcutaneously twice a week in the SHAM group and OVX group.After 12 weeks of drug administration,the samples were taken.The organ coefficients,main organ pathological sections,and bone histopathological sections were observed,and the micro CT,L4 biomechanics and serum biochemical indicators were analyzed.Results:The uterine coefficient of Sham group was(0.0054±0.0007)significantly higher than that of OVX group(0.0026±0.0009)and ALN group(0.0025±0.0007),and the difference was statistically significant(P<0.05).No obvious lesions or toxic or side effects were observed in the main organs.Compared with the OVX group,the ALN group with decalcified sections of bone tissue had compact trabecular structure and fewer adipocytes.Micro-CT results showed that the Tb.BMD,Tb.N,Tb.Th and Tb.BV/TV values of the ALN group were significantly increased compared with those of the OVX group,but the Tb.Sp value was significantly decreased,and the difference was statistically significant(P<0.05).In L4 vertebral body biomechanics,the elastic modulus(50.29±13.43)and maximum load number(29.83±4.92)of ALN group were significantly higher than those of OVX group(14.77±3.12)and maximum load number(11.57±3.18),and the difference was statistically significant(P<0.05).Compared with the OVX group,the serum OCN and PINP indicators of bone formation in the ALN group were increased,while the bone resorption indicators TRACP-5b and CTX-I were decreased,with statistical significance(P<0.05).Conclusion:Alendronate sodium improves bone quality by increasing bone density,improving bone microstructure,increasing bone strength,promoting bone formation and inhibiting bone resorption,without obvious toxic and side effects on organs.

Pomegranate peel extract lessens histopathologic changes and restores antioxidant homeostasis in the hippocampus of rats with aluminium chloride-induced Alzheimer’s disease

Objective:To investigate the neuroprotective efficacy of pomegranate and ellagic acid on the histopathological changes in the hippocampus of an aluminium chloride(AlCl<sub>3)induced rat model of Alzheimer’s disease.Methods:Sprague Dawley rats were divided into 4 groups(n=10each):GroupⅠ:serving as negative control;GroupⅡ,Alzheimer model,induced by administration of 17 mg/kg bw AlCl3;GroupⅢ,administered the same dose of AlCl3 with 50 mg/kg of pomegranate peel extract and GroupⅣ:administered ellagic acid(50 mg/kg)in addition to the same dose of AlCl3.The medication given to all groups continued for 28 days.All were given the compounds by gastric gavage.Radial arm maze test,hippocampus antioxidant markers,histopathology of the dentate gyrus,and CA3 of the hippocampus were evaluated.Results:Rats treated with pomegranate peel extract exposed to radial arm maze test showed less number of errors and reduced time needed to reach the criterion.There was an increase in the levels of glutathione,catalase,and total antioxidant capacity and decreased lipid peroxidation products.Histopathological features in dentate gyrus and CA3 as apoptosis and chromatolysis of pyramidal cells and granular layer,respectively,were decreased.Alzheimer characteristic neurofibrillary tangles and senile plaques were reduced.Treatment with ellagic acid ameliorated the pathological results but to a statistically lower level.Conclusions:Pomegranate peel extract alleviates memory deficit and restores antioxidant homeostasis following degenerative changes in the hippocampus induced by aluminium chloride in rats.

Evolution of human kidney allograft pathology diagnostics through 30 years of the Banff classification process

The second half of the previous century witnessed a tremendous rise in the number of clinical kidney transplants worldwide.This activity was,however,accompanied by many issues and challenges.An accurate diagnosis and appropriate management of causes of graft dysfunction were and still are,a big challenge.Kidney allograft biopsy played a vital role in addressing the above challenge.However,its interpretation was not standardized for many years until,in 1991,the Banff process was started to fill this void.Thereafter,regular Banff meetings took place every 2 years for the past 30 years.Marked changes have taken place in the interpretation of kidney allograft biopsies,diagnosis,and classification of rejection and other non-rejection pathologies from the original Banff 93 classification.This review attempts to summarize those changes for increasing the awareness and understanding of kidney allograft pathology through the eyes of the Banff process.It will interest the transplant surgeons,physicians,pathologists,and allied professionals associated with the care of kidney transplant patients.

Collision tumor of primary malignant lymphoma and adenocarcinoma in the colon diagnosed by molecular pathology:A case report and literature review

BACKGROUND Collision tumors of primary malignant lymphoma and adenocarcinoma in the colon are rare.Primary diffuse large B-cell lymphoma(DLBCL)–adenocarcinoma collision tumors are especially rare.CASE SUMMARY A 74-year-old woman presented with abdominal pain of 1 mo duration.Biopsy under colonoscopy revealed adenocarcinoma of the ascending colon.Subsequently,the patient underwent laparoscopic radical resection of right colon cancer with lymph node dissection.A collision tumor was found incidentally through postoperative pathological sampling.Genetic analysis showed a collision tumor of DLBCL with germinal center B-cell subtype and TP53 mutation,and adenocarcinoma arising in a tubulovillous adenoma in the colon,with BRAF mutation and mutL homolog 1 promoter methylation.The patient died 3 mo after surgery.To our knowledge,this is the 23rd reported case of collision tumor of colorectal adenocarcinoma and lymphoma.The mean age of the 23 patients was 73 years.The most common site was the cecum.There were 15 cases with followup data including 11 living and four dead with a 3-year overall survival rate of 71.5%.CONCLUSION Based on pathological and genetic analysis,surgery combined with chemotherapy or chemoradiotherapy may have good therapeutic effects for collision tumor.

Transitioning of renal transplant pathology from allograft to xenograft and tissue engineering pathology:Are we prepared?

Currently,the most feasible and widely practiced option for patients with endstage organ failure is the transplantation of part of or whole organs,either from deceased or living donors.However,organ shortage has posed and is still posing a big challenge in this field.Newer options being explored are xenografts and engineered/bioengineered tissues/organs.Already small steps have been taken in this direction and sooner or later,these will become a norm in this field.However,these developments will pose different challenges for the diagnosis and management of problems as compared with traditional allografts.The approach to pathologic diagnosis of dysfunction in these settings will likely be significantly different.Thus,there is a need to increase awareness and prepare transplant diagnosticians to meet this future challenge in the field of xenotransplantation/regenerative medicine.This review will focus on the current status of transplant pathology and how it will be changed in the future with the emerging scenario of routine xenotransplantation.

Preliminary Exploration of All-English Teaching in Pathology for International Students

With the development of medical education in China, the education of international students has gradually become an important part of China’s higher education. Pathology is a bridge course connecting basic medicine and clinical medicine, and is a compulsory course for international medical students. In order to improve the quality of all-English teaching in pathology, according to the characteristics of international students and the discipline characteristics of pathology, this paper discussed the problems existing in the pathology teaching of international students, such as language communication, teacher training, textbook selection, teaching content arrangement, etc., aiming at exploring ways to solve these problems and improve the learning effect of international students from teaching practice.

Morphologic damage of neurons in hippocampus （CA－1） following focal brain cortex contusion： a quantitative histopathologic st

The present study was designed to investigate the hippocampus injury in response to focal brain trauma. Neuron damage in the cortex and the hippocampus (CA-1) was assessed quantitatively with light microscope through a cerebral contusion model of rat. The