The spatial transcriptomic landscape of non-small cell lung cancer brain metastasis

Brain metastases (BrMs) are a common occurrence in lung cancer with a dismal outcome. To understand the mechanism of metastasis to inform prognosis and treatment, here we analyze primary and metastasized tumor specimens from 44 non-small cell lung cancer patients by spatial RNA sequencing, affording a whole transcriptome map of metastasis resolved with morphological markers for the tumor core, tumor immune microenvironment (TIME), and tumor brain microenvironment (TBME). Our data indicate that the tumor microenvironment (TME) in the brain, including the TIME and TBME, undergoes extensive remodeling to create an immunosuppressive and fibrogenic niche for the BrMs. Specifically, the brain TME is characterized with reduced antigen presentation and B/T cell function, increased neutrophils and M2-type macrophages, immature microglia, and reactive astrocytes. Differential gene expression and network analysis identify fibrosis and immune regulation as the major functional modules disrupted in both the lung and brain TME. Besides providing systems-level insights into the mechanism of lung cancer brain metastasis, our study uncovers potential prognostic biomarkers and suggests that therapeutic strategies should be tailored to the immune and fibrosis status of the BrMs.

Astrocyte Role in Temporal Lobe Epilepsy and Development of Mossy Fiber Sprouting

Epilepsy affects approximately 50 million people worldwide, with 60% of adult epilepsies presenting an onset of focal origin. The most common focal epilepsy is temporal lobe epilepsy (TLE). The role of astrocytes in the presentation and development of TLE has been increasingly studied and discussed within the literature. The most common histopathological diagnosis of TLE is hippocampal sclerosis. Hippocampal sclerosis is characterized by neuronal cell loss within the Cornu ammonis and reactive astrogliosis. In some cases, mossy fiber sprouting may be observed. Mossy fiber sprouting has been controversial in its contribution to epileptogenesis in TLE patients, and the mechanisms surrounding the phenomenon have yet to be elucidated. Several studies have reported that mossy fiber sprouting has an almost certain co-existence with reactive astrogliosis within the hippocampus under epileptic conditions. Astrocytes are known to play an important role in the survival and axonal outgrowth of central and peripheral nervous system neurons, pointing to a potential role of astrocytes in TLE and associated cellular alterations. Herein, we review the recent developments surrounding the role of astrocytes in the pathogenic process of TLE and mossy fiber sprouting, with a focus on proposed signaling pathways and cellular mechanisms, histological observations, and clinical correlations in human patients.

Hippocampal dentate granule cells in temporal lobe epilepsy: A morphometry and transcriptomic study

The dentate gyrus (DG) plays a critical role in hippocampal circuitry, providing a "gate-like" function to the downstream cornu ammonis (CA) sectors. Despite this critical role, pathologies in DG are less commonly described than those in the CA sectors in the diagnosis of mesial temporal lobe epilepsy (mTLE). To elucidate the role of the DG in mTLE, we analysed hippocampal sclerosis (HS), no-HS, non-TLE epilepsy control, and non-epilepsy control cohorts using morphometry and gene expression profiling techniques. Morphometry techniques analysed DG cell spacing, nucleus size, and nucleus circularity. Our data show distinct DG morphometry and RNA expression profiles between HS and No-HS. Dentate granule cells are more dispersed in patients with HS, and the DG shows an elevated expression of the complement system, apoptosis, and extracellular matrix remodelling-related RNA. We also observe an overall decrease in neurogenesis-related RNA in HS DG. Interestingly, regardless of the pathological diagnosis, the DG morphometry correlates with post-operative outcomes. Increased cell spacing is observed in the DG of mTLE cases that achieve seizure freedom post-operatively. This study reveals the possible prognostic value of DG morphometry, as well as supporting the notion that HS and no-HS TLE may be distinct disease entities with differing contributing mechanisms.

Kinome and phosphoproteome reprogramming underlies the aberrant immune responses in critically ill COVID-19 patients

SARS-CoV-2 infection triggers extensive host immune reactions, leading to severe diseases in certain individuals. However, the molecular basis underlying the excessive yet non-productive immune responses in severe COVID-19 remains incompletely understood. In this study, we conducted a comprehensive analysis of the peripheral blood mononuclear cell (PBMC) proteome and phosphoproteome in sepsis patients positive or negative for SARS-CoV-2 infection, as well as healthy subjects, using quantitative mass spectrometry. Our findings demonstrate dynamic changes in the COVID-19 PBMC proteome and phosphoproteome during disease progression, with distinctive protein or phosphoprotein signatures capable of distinguishing longitudinal disease states. Furthermore, SARS-CoV-2 infection induces a global reprogramming of the kinome and phosphoproteome, resulting in defective adaptive immune response mediated by the B and T lymphocytes, compromised innate immune responses involving the SIGLEC and SLAM family of immunoreceptors, and excessive cytokine-JAK-STAT signaling. In addition to uncovering host proteome and phosphoproteome aberrations caused by SARS-CoV-2, our work recapitulates several reported therapeutic targets for COVID-19 and identified numerous new candidates, including the kinases PKG1, CK2, ROCK1/2, GRK2, SYK, JAK2/3, TYK2, DNA-PK, PKCδ, and the cytokine IL-12.

Global pannexin 1 deletion increases tumor-infiltrating lymphocytes in the BRAF/Pten mouse melanoma model

Immunotherapies for malignant melanoma seek to boost the anti-tumoral response of CD8+ T cells, but have a limited patient response rate, in part due to limited tumoral immune cell infiltration. Genetic or pharmacological inhibition of the pannexin 1 (PANX1) channel-forming protein is known to decrease melanoma cell tumorigenic properties in vitro and ex vivo. Here, we crossed Panx1 knockout (Panx1-/-) mice with the inducible melanoma model BrafCA, PtenloxP, Tyr::CreERT2 (BPC). We found that deleting the Panx1 gene in mice does not reduce BRAF(V600E)/Pten-driven primary tumor formation or improve survival. However, tumors in BPC-Panx1-/- mice exhibited a significant increase in the infiltration of CD8+ T lymphocytes, with no changes in the expression of early T-cell activation marker CD69, lymphocyte activation gene 3 protein (LAG-3) checkpoint receptor, or programmed cell death ligand-1 (PD-L1) in tumors when compared to the BPC-Panx1+/+ genotype. Our results suggest that, although Panx1 deletion does not overturn the aggressive BRAF/Pten-driven melanoma progression in vivo, it does increase the infiltration of effector immune T-cell populations in the tumor microenvironment. We propose that PANX1-targeted therapy could be explored as a strategy to increase tumor-infiltrating lymphocytes to boost anti-tumor immunity.

BACTERIAL PROFILE, ANTIMICROBIAL RESISTANCE, AND FACTORS ASSOCIATED WITH URINARY TRACT INFECTION AMONG PREGNANT WOMEN AT HOSANNA TOWN HEALTH FACILITIES, CENTRAL ETHIOPIA

Urinary tract infection in pregnancy is a common microbial infection. Antimicrobial resistance among uropathogens is becoming a major health problem worldwide. The antimicrobial agents used to manage urinary tract infections during pregnancy should be carefully chosen. Therefore, this study aimed to determine the bacterial profile, antibiotic susceptibility pattern, and factors associated with urinary tract infection among pregnant women at Hosanna town public health facilities. A facility-based cross-sectional study was conducted from March to August 2022 on a total of 312 pregnant women who attended antenatal care at Hosanna Town public health facilities. Sociodemographic, clinical data, and related information were collected by using a pre-tested questionnaire. In addition, mid-stream urine specimens were collected from study participants. Bacterial pathogens were identified by standard bacteriological techniques. Antibiotic susceptibility testing was performed by using the Kirby Bauer disk diffusion method. The data were analyzed by using SPSS version 25. Chi-square and odds ratios were calculated and a P-value≤0.05 at a 95% confidence interval was considered statistically significant. The results were presented with words and tables. Of a total of pregnant women, 59/312(18.9%) (95% CI: 14.7-23.7) were found to have significant bacteriuria. The predominant isolates were Escherichia coli (E. coli) 22(34.4%), followed by coagulase-negative staphylococci (CoNS) 10(15.6%), Staphylococci aureus (S. aureus) 7(10.9%), and Klebsiella pneumoniae (K. pneumoniae) 6(9.4%). Overall, 78.1% of these isolates were multidrug-resistant (MDR). Gram-negative bacteria were susceptible to meropenem (97.6%), gentamicin (85.7%), nitrofurantoin (82.1%), ciprofloxacin (73.8%), amoxicillin-clavulanic acid (73.8%) and ceftriaxone (71.8%), but highly resistant to ampicillin (95.5%), trimethoprim-sulfamethoxazole (74.4%), doxycycline (71.8%), cefuroxime (69.2%), and cephalexin (69.2%). The gram-positive bacteria were susceptible to gentamicin (86.4%), erythromycin (81.8%), and nitrofurantoin (77.3%): whereas they showed a high level of resistance to penicillin (72.7%), doxycycline (54.5%), trimethoprim-sulfamethoxazole (52.9%), and cefoxitin (52.9%). No formal education for the participant (AOR: 2.86, 95% CI: 1.03-7.98, p=0.044), family monthly income <1500 birr (AOR: 3.19, 95% CI: 1.48-6.89, p=0.003), and previous history of UTI (AOR: 4.52, 95% CI: 2.04-10.03, p=0.001) were significantly associated with bacteriuria. This study revealed a high prevalence of bacterial urinary tract infection among pregnant women and low susceptibility to ampicillin, trimethoprim-sulfamethoxazole, cefuroxime, and cephalexin. Therefore, regularly, culture-based bacterial identification and antibiotic susceptibility testing should be performed. Alternatively, empiric antibiotic therapy should consider the prevalence of antibiotic-resistant uropathogens and the factor that may increase the urinary tract infection occurrence due to multi-drug resistant uropathogens.

Acute ischemic stroke management in Lebanon: obstacles and solutions

Management of acute stroke varies greatly within and between different countries. This study assesses the current practices of physicians in Lebanon routinely involved in ischemic stroke (IS) management. We conducted a prospective observational study of patients hospitalized at 8 different Lebanese hospitals in the period August 1, 2015 to July 31, 2016, with a diagnosis of acute stroke. Baseline characteristics and data on diagnostic studies, as well as treatments received during hospitalization and at discharge, were collected and analyzed. Two hundred and three strokes/transient ischemic attacks (TIAs) were recorded but only 173 patients (85%) with ischemic events were included in the study. The patients' mean age was 69.8±12.7 years. All underwent brain imaging (CT scan and/or MRI) on admission. All ISs were managed by a neurologist, and patient management included consultation of a cardiologist. Hypertension was the most prevalent risk factor (78.6%), followed by a current cigarette smoking habit (50.3%), diabetes mellitus (42.8%), hypercholesterolemia (39.9%), previous stroke or TIA (17.3%), and atrial fibrillation (14.7%). Only four patients (accounting for 2.5% of the ISs) received thrombolytic therapy. More than 89% of the patients were discharged on at least one anti-hypertensive drug, 89.2% on statins and 37.6% on antidiabetic medications. More than 55% of patients were dependent at discharge, as shown by a modified Rankin Scale (mRS) score of 0-2, whereas 33% were independent (mRS score of 3-5). There are many challenges facing stroke care in Lebanon, and there is potential for improvement in this setting. Reperfusion therapy is still largely underused and remains a major challenge in achieving guideline-based reperfusion goals.

Expression of pannexin1 in lung cancer brain metastasis and immune microenvironment

Brain metastases are the most common central nervous system malignancy, and the leading cause of cancer-related deaths. Non-small cell lung carcinomas (NSCLC) comprise the most common cell of origin. Immunotherapy, particularly checkpoint inhibitors, has emerged as the standard of care for many patients with advanced lung cancer. Pannexin1 (PANX1) is a transmembrane glycoprotein that forms large-pore channels and has been reported to promote cancer metastasis. However, the roles of PANX1 in lung cancer brain metastases and tumor immune microenvironment have not been characterized. 42 patient-matched formalin-fixed paraffin-embedded tissue samples from lung carcinomas and the subsequent brain metastases were constructed into three tissue microarrays (TMAs). PANX1 and markers of tumor-infiltrating immune cells (CD3, CD4, CD8, CD68, and TMEM119) were assessed using immunohistochemistry and digital image analysis. The expression of PANX1 was significantly higher in brain metastases than in their paired primary lung carcinoma. The high levels of PANX1 in lung carcinoma cells in the brain inversely correlated with infiltration of peripheral blood-derived macrophages. Our findings highlight the role of PANX1 in the progression of metastatic NSCLC, and the potential therapeutic approach of targeting PANX1 enhances the efficacy of immune checkpoint inhibitors in brain metastasis.