Intranasal Delivery of Mitochondria Attenuates Brain Injury by AMPK and SIRT1/PGC-1α Pathways in a Murine Model of Photothrombotic Stroke

Ischemic stroke is one of the major causes of morbidity and mortality worldwide. Mitochondria play a vital role in the pathological processes of cerebral ischemic injury, but its transplantation and underlying mechanisms remain unclear. In the present study, we examined the effects of mitochondrial therapy on the modulation of AMPK and SIRT1/PGC-1α signaling pathway, oxidative stress, and NLRP3 inflammasome activation after photothrombotic ischemic stroke (pt-MCAO). The adult male mice were subjected to the pt-MCAO in which the proximal-middle cerebral artery was exposed with a 532-nm laser beam for 4 min by retro-orbital injection of a photosensitive dye (Rose Bengal: 15 mg/kg) before the laser light exposure and isolated mitochondria (100 μg protein) were administered intranasally at 30 min, 24 h, and 48 h following post-stroke. After 72 h, mice were tested for neurobehavioral outcomes and euthanized for infarct volume, brain edema, and molecular analysis. First, we found that mitochondria therapy significantly decreased brain infarct volume and brain edema, improved neurological dysfunction, attenuated ischemic stroke-induced oxidative stress, and neuroinflammation. Second, mitochondria treatment inhibited NLRP3 inflammasome activation. Finally, mitochondria therapy accelerated p-AMPKα(Thr172) and PGC-1α expression and resorted SIRT1 protein expression levels in pt-MCAO mice. In conclusion, our results demonstrate that mitochondria therapy exerts neuroprotective effects by inhibiting oxidative damage and inflammation, mainly dependent on the heightening activation of the AMPK and SIRT1/PGC-1α signaling pathway. Thus, intranasal delivery of mitochondria might be considered a new therapeutic strategy for ischemic stroke treatment.

Intrusion of Arabian Sea high salinity water and monsoon-associated processes modulate planktic foraminiferal abundance and carbon burial in the southwestern Bay of Bengal

The unicellular calcareous planktic foraminifera sequester a significant portion of the carbon dioxide dissolved in the ocean, thus burying the carbon in sediments for millions of years. The global warming and associated processes are likely to affect the planktic foraminiferal abundance and diversity. Therefore, their baseline distribution has to be documented and correlated with ambient parameters to assess its fate under different climate change scenarios. Here, we report an exceptionally high abundance of planktic foraminifera and thus large carbon burial in the southwestern Bay of Bengal. The very high absolute abundance of planktic foraminifera in the Cauvery River basin is attributed to biannual productivity, warmer and saline waters. Globigerinita glutinata is the highest abundant species followed by Globigerinoides ruber and Globigerina bulloides. Globigerina bulloides is abundant on the shelf, where the upwelling is more frequent. The relative abundance of Globorotalia menardii is positively correlated with thermocline salinity and negatively correlated with thermocline temperature. Similarly, Neogloboquadrina dutertrei and Globoquadrina conglomerata are negatively correlated with mixed layer as well as thermocline temperature and mixed layer salinity. Both these species are positively correlated with thermocline salinity. Globigerina falconensis is more abundant in the southernmost transect influenced by intense winter monsoon precipitation. We report that G. ruber prefers high saline and warmer waters with the highest abundance in the southernmost transect. From the foraminiferal distribution, it is evident that the temperature and salinity of the mixed layer as well as thermocline, food availability, and monsoon-associated processes affect the planktic foraminiferal abundance and thus carbon burial in the southwestern Bay of Bengal. The changes in influx of southeastern Arabian Sea water will affect the planktic foraminiferal population and subsequent carbon burial in the southwestern Bay of Bengal.

A dynamical measure of the black hole mass in a quasar 11 billion years ago

Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH)1-3. These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase4-6. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3)7. Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-μas (0.31-pc) spatial offset between the red and blue photocentres of the Hα line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 × 108 solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 × 1011 solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems.

Genetic and Pharmacological Modulation of P75 Neurotrophin Receptor Attenuate Brain Damage After Ischemic Stroke in Mice

The precursor nerve growth factor (ProNGF) and its receptor p75 neurotrophin receptor (p75NTR) are upregulated in several brain diseases, including ischemic stroke. The activation of p75NTR is associated with neuronal apoptosis and inflammation. Thus, we hypothesized that p75NTR modulation attenuates brain damage and improves functional outcomes after ischemic stroke. Two sets of experiments were performed. (1) Adult wild-type (WT) C57BL/6 J mice were subjected to intraluminal suture-middle cerebral artery occlusion (MCAO) to induce cerebral ischemia. Pharmacological inhibitor of p75NTR, LM11A-31 (50 mg/kg), or normal saline was administered intraperitoneally (IP) 1 h post-MCAO, and animals survived for 24 h. (2) Adult p75NTR heterozygous knockout (p75NTR+/-) and WT were subjected to photothrombotic (pMCAO) to induce ischemic stroke, and the animals survived for 72 h. The sensory-motor function of animals was measured using Catwalk XT. The brain samples were collected to assess infarction volume, edema, hemorrhagic transformation, neuroinflammation, and signaling pathway at 24 and 72 h after the stroke. The findings described that pharmacological inhibition and genetic knocking down of p75NTR reduce infarction size, edema, and hemorrhagic transformation following ischemic stroke. Additionally, p75NTR modulation significantly decreased several anti-apoptosis markers and improved sensory motor function compared to the WT mice following ischemic stroke. Our observations exhibit that the involvement of p75NTR in ischemic stroke and modulation of p75NTR could improve the outcome of ischemic stroke by increasing cell survival and enhancing motor performance. LM11A-31 has the potential to be a promising therapeutic agent for ischemic stroke. However, more evidence is needed to illuminate the efficacy of LM11A-31 in ischemic stroke.

Identifying canonical and replicable multi-scale intrinsic connectivity networks in 100k+ resting-state fMRI datasets

Despite the known benefits of data-driven approaches, the lack of approaches for identifying functional neuroimaging patterns that capture both individual variations and inter-subject correspondence limits the clinical utility of rsfMRI and its application to single-subject analyses. Here, using rsfMRI data from over 100k individuals across private and public datasets, we identify replicable multi-spatial-scale canonical intrinsic connectivity network (ICN) templates via the use of multi-model-order independent component analysis (ICA). We also study the feasibility of estimating subject-specific ICNs via spatially constrained ICA. The results show that the subject-level ICN estimations vary as a function of the ICN itself, the data length, and the spatial resolution. In general, large-scale ICNs require less data to achieve specific levels of (within- and between-subject) spatial similarity with their templates. Importantly, increasing data length can reduce an ICN's subject-level specificity, suggesting longer scans may not always be desirable. We also find a positive linear relationship between data length and spatial smoothness (possibly due to averaging over intrinsic dynamics), suggesting studies examining optimized data length should consider spatial smoothness. Finally, consistency in spatial similarity between ICNs estimated using the full data and subsets across different data lengths suggests lower within-subject spatial similarity in shorter data is not wholly defined by lower reliability in ICN estimates, but may be an indication of meaningful brain dynamics which average out as data length increases.

Healthcare-associated infections among neonates and children in Pakistan: findings and the implications from a point prevalence survey

BACKGROUND

Healthcare-associated infections (HAIs) increase morbidity, mortality and costs. The overall prevalence of HAIs is greater in low- and middle-income countries due to poor resources and infrastructure, with the incidence of HAIs greater among neonates and children. There is a need to understand the current situation in Pakistan including key drivers to improve future care.

METHODS

Point prevalence survey (PPS) of HAIs in the children's wards of 19 public sector secondary- and tertiary-care hospitals of Pakistan and associated key drivers.

RESULTS

A total of 1147 children were included in the PPS. 35.7% were neonates with 32.8% aged >1-5 years. 35.2% were admitted to the intensive care units (ICUs). Peripheral, central venous and urinary catheters were present in 48%, 2.9% and 5.6% of the patients, respectively. A total of 161 HAIs from various pathogens were observed in 153 cases, giving a prevalence of 13.3%. The majority of HAIs were caused by Staphylococcus aureus (31.7%) followed by Klebsiella pneumoniae (22.9%) and Escherichia coli (17.4%). Bloodstream infections were identified in 42 cases followed by lower-respiratory-tract infections in 35. Increased length of hospital stays and being admitted to the ICU, 'rapidly fatal' patients under the McCabe and Jackson criteria, central and peripheral catheterization, and invasive mechanical ventilation were, associated with higher HAIs (P<0.001). 99.7% of HAI patients fully recovered and were discharged from the hospital.

CONCLUSION

There is a high prevalence of HAIs among neonates and children admitted to health facilities in Pakistan. Infection prevention and control measures should be implemented to help prevent future HAIs.

Development and validation of a reliable rabbit model of limbal stem cell deficiency by mechanical debridement using an ophthalmic burr

A simple and reproducible method is necessary to generate reliable animal models of limbal stem cell deficiency (LSCD) for assessing the safety and efficacy of new therapeutic modalities. This study aimed to develop and validate a rabbit model of LSCD through mechanical injury. The corneal and limbal epithelium of New Zealand White rabbits (n = 18) were mechanically debrided using an ophthalmic burr (Algerbrush II) with a 1.0-mm rotating head after 360° conjunctival peritomy. The debrided eyes were serially evaluated for changes in corneal opacity, neo-vascularization, epithelial defect and corneal thickness using clinical photography, slit lamp imaging, fluorescein staining, and anterior segment optical coherence tomography scanning (AS-OCT). Following this, an assessment of histopathology and phenotypic marker expression of the excised corneas was conducted. The experimental eyes were grouped as mild (n = 4), moderate (n = 10), and severe (n = 4) based on the grade of LSCD. The moderate group exhibited abnormal epithelium, cellular infiltration in the stroma, and vascularization in the central, peripheral, and limbal regions of the cornea. The severe group demonstrated central epithelial edema, peripheral epithelial thinning with sparse goblet cell population, extensive cellular infiltration in the stroma, and dense vascularization in the limbal region of the cornea. A significant decrease in the expression of K12 and p63 (p < 0.0001) was observed, indicating the loss of corneal epithelium and limbal epithelial stem cells in the LSCD cornea. This study demonstrates that the Alger brush-induced mechanical debridement model provides a reliable model of LSCD with comprehensive clinic-pathological features and that is well suited for evaluating novel therapeutic and regenerative approaches.

Neuroprotective effect of ropinirole against Aβ1-42 -induced neurochemical perturbations and cognitive impairments in a rodent model

The primary objective of this study was to investigate the protective effects of ropinirole (ROP) medication given for an extended period following the induction of cognitive decline, oxidative stress, and deterioration of mitochondria in a Wistar rat model by Aβ1-42 . This study aimed to examine the neuroprotective efficacy of ROP in a stereotaxis model of AD. The Wistar rats were randomly assigned into four groups. Group I was considered as a sham, group II served as Aβ-infusion alone, Group III was Aβ1-42 + ROP (5 mg/kg/i.p.), and Group IV was Aβ1-42 + ROP (10 mg/kg/i.p.). Our research revealed that ROP (10 mg/kg, b.wt.) attenuates the cognitive deficits caused by Aβ1-42 -infused, which also correlates with the barnes maze, where (10 mg/kg, b.w.t.) shows significant improvement in spatial learning and memory. At the same time, ROP was rescued from oxidative damage, decreased lipid peroxidation rates, and inhibited acetylcholinesterase activity caused, demonstrating antioxidant benefits. In addition, a higher dose of ROP restored mitochondrial membrane potential in Aβ1-42 rats. Furthermore, histopathological examination showed that ROP treatment reduced neuronal loss, especially in the hippocampus. We conclude that ROP's protective effects in reducing oxidative stress and modulating mitochondrial function might have a propensity in AD pathogenesis.

A modified murine photothrombotic stroke model: a minimally invasive and reproducible cortical and sub-cortical infarct volume and long-term deficits

Ischemic stroke is one of the major causes of devastating neurological disabilities and mortality worldwide. Despite extensive research for treatment approaches, there remains limited therapy in the stroke field. Therefore, more research is required for reproducibility to understand stroke pathology in pre-clinical studies. In the current modified method, mice were subjected to photothrombotic stroke (pt-MCA; proximal-middle cerebral artery was exposed with a 532 nm laser beam for 4 min) by retro-orbital injection of photosensitive dye, Rose Bengal (15 mg/kg) before the laser light exposure. Sensorimotor deficits were assessed by rotarod and catwalk test at 72 h following post-pt-MCAO, and brain samples were collected for infarct volume and hemorrhagic transformation (HT) assessments. Cognitive impairments were assessed by a novel objective recognition and Morris's water maze tests at the end of the follow-up. pt-MCAO animals significantly reduced body weight and impaired motor and cognitive functions. Furthermore, pt-MCAO animals showed apparent infarction, brain edema, and increased HT compared to the sham animals. Additionally, this method enables concurrent measurement of short-term and long-term neurological dysfunction with relatively larger cortical and sub-cortical infarct volume following pt-MCAO. With respect to the other models, this modified model offers enhanced reproducibility regarding infarct volume and cognitive/functional outcomes and avoids complications associated with critical surgeries and craniotomy. In conclusion, this modified model helps to understand stroke pathogenesis and minimize the animals' numbers which help to increase the scientific and statistical potential in pre-clinical studies.

Age-related pathophysiological alterations in molecular stress markers and key modulators of hypoxia

Alzheimer's disease (AD) is characterized by an adverse cellular environment and pathological alterations in distinct brain regions. The development is triggered or facilitated by a condition such as hypoxia or ischemia, or inflammation and is associated with disruptions of fundamental cellular functions, including metabolic and ion homeostasis. Increasing evidence suggests that hypoxia may affect many pathological aspects of AD, including oxidative stress, mitochondrial dysfunction, ER stress, amyloidogenic processing of APP, and Aβ accumulation, which may collectively result in neurodegeneration. Further investigation into the relationship between hypoxia and AD may provide an avenue for the effective preservation and pharmacological treatment of this neurodegenerative disease. This review summarizes the effects of normoxia and hypoxia on AD pathogenesis and discusses the underlying mechanisms. Regulation of HIF-1α and the role of its key players, including P53, VEGF, and GLUT1, are also discussed.

A review of rabbit models of meibomian gland dysfunction and scope for translational research

Dry eye disease (DED) is an emerging global health concern with meibomian gland dysfunction (MGD) being the most common subtype of DED. Despite being quite prevalent, the pathophysiological mechanisms governing MGD are poorly understood. Animal models for MGD can be a valuable resource to advance our understanding of this entity and explore novel diagnostic and therapeutic modalities. Although a lot of literature on rodent MGD models exists, a comprehensive review on rabbit animal models is lacking. Rabbits offer a great advantage over other animals as models for studying both DED and MGD. Rabbits have a widely exposed ocular surface and meibomian gland anatomy comparable with humans, which makes performing dry eye diagnostic tests possible using clinically validated imaging platforms. The existing MGD models in rabbits can broadly be classified as pharmacologically induced and surgically induced models. Most models show keratinization of the meibomian gland orifice with plugging as the final common pathway for developing MGD. Thus, understanding the advantages and disadvantages of each rabbit MGD model can help researchers choose the appropriate experimental plan based on the objective of the study. In this review, we discuss the comparative anatomy of the meibomian glands in humans and rabbits, various rabbit models of MGD, translational applications, unmet needs, and future directions in developing MGD models in rabbits.

Abstract TMP114: Modulation Of P75ntr Improves Neuroprotection Following Ischemic Stroke

Background: Stroke is a serious cause of mortality in the United States. Tissue plasminogen activator (tPA) is the only effective drug. However, it increases the risk of cerebral hemorrhage due to its narrow therapeutic window. Previous studies have shown the role of neurotrophins in several brain diseases. P75 NTR which is the receptor of tumor necrosis family is highly expressed in stroke and associated with neuronal apoptosis. Downregulation of p75 NTR attenuates brain injury. This study aims to find the role of p75 NTR in the outcome of stroke.

Methods: Two different sets of experiments were performed. 1. Young adult C57BL/6 mice were subjected to ischemic stroke using intraluminal suture model. P75 NTR modulator (LM11A-31) was administered following stroke. Brain samples were collected 24 hours after injury. 2. Young adult C57BL/6 and p75 heterozygous mice were subjected to stroke using Rose Bengal photothrombotic method. Mice were tested for neurobehavioral analysis and samples were collected 72h after stroke.

Results: We found that administration of LM11A-31 significantly reduced infarction volume, edema, and hemorrhagic transformation 24h after stroke in mice. Also, LM11A-31 reduced several inflammatory markers including tumor necrosis factor- alpha (TNF-α), nuclear factor kappa-light-chain (p-NFκb/t-NFκb), and c- Jun N-terminal kinases (p-JNK/t-JNK), and significantly increased the expression of several anti-inflammatory signaling, including protein kinase B (p-Akt/t-Akt) and extracellular signal-regulated kinase ½ (p-ERK1/2/t-ERK1/2) after stroke. Furthermore, we found that p75 NTR heterozygous mice remarkably demonstrated less infarction, edema, and hemorrhagic transformation than wild-type mice after stroke. Moreover, p75 NTR heterozygous significantly showed better motor function.

Conclusion: This study suggests that p75 NTR modulation can be a potential pharmacological target for improving the outcome of ischemic stroke.

Abstract WP234: Mitochondria Therapy Mitigates Neuroinflammation And Provides Neuroprotection Against Ischemic Stroke In Mice

Background: Ischemic stroke is the second prevalent life-threat problem associated with long-lasting neurological disabilities and a high mortality rate worldwide. Despite this, therapeutic options remain limited. Recently, mitochondria transplantation therapy has emerged as a potential approach for increasing brain protection. This study aimed to investigate the protective role of mitochondria transplantation against ischemic stroke-induced behavioral deficits and molecular alterations in a photothrombotic stroke model.

Methods: Ischemic stroke was induced by a Rose Bengal photothrombosis method in young adult C57BL/6 mice. Repeated doses of isolated liver mitochondria (100μg/mouse) were administrated intranasally at 1 h, 3 h, 24 h, and 48 h post-stroke. After 72 h, mice were tested for behavioral outcomes and euthanized, and tissues were harvested to measure infarct volume, brain edema, and molecular analysis.

Results: Mitochondria-treated mice showed a significant improvement in behavioral outcomes, reduction in infarct size, and brain edema compared to the vehicle-treated group. Additionally, mitochondria significantly inhibited the protein expression of NOD-like receptor protein-3, phospho-nuclear factor kappa-B, cleaved-interleukin-1β, apoptosis-associated speck-like protein, glial fibrillary acidic protein, and ionized calcium-binding adapter molecule-1 proteins. Furthermore, mitochondria treatment showed a lower expression of nitrotyrosine, and 4-hydroxynonenal and higher expression of endothelial nitric oxide synthase and sulfotransferase-4A1 proteins, oxidative stress markers ( Table 1 ).

Conclusion: Taken together, these data indicate that mitochondria reveal neuroprotection through the attenuation of inflammation against stroke. Further investigations into the role of neuroprotection of mitochondria transplantation are needed to determine whether it can be an effective therapy for stroke patients.

Role of melatonin and quercetin as countermeasures to the mitochondrial dysfunction induced by titanium dioxide nanoparticles

AIM

Due to the growing commercialization of titanium dioxide nanoparticles (TNPs), it is necessary to use these particles in a manner that is safe, healthy and environmental friendly. Through reactive oxygen species (ROS) generation, it has been discovered that TNPs have a harmful effect on the brain. The aim of this study is to provide valuable insights into the possible mechanisms of TNPs induced mitochondrial dysfunction in brain and its amelioration by nutraceuticals, quercetin (QR) and melatonin (Mel) in in vitro and in vivo conditions.

MATERIALS AND METHODS

Whole brain mitochondrial sample was used for in-vitro evaluation. Pre-treatment of QR (30 μM) and Mel (100 μM) at 25 °C for 1 h was given prior to TNPs (50 μg/ml) exposure. For in-vivo study, male Wistar rats were divided into four groups. Group I was control and group II was exposed to TNPs (5 mg/kg b.wt., i.v.). QR (5 mg/kg b.wt.) and Mel (5 mg/kg b.wt.) were given orally as pre-treatment in groups III and IV, respectively. Biochemical parameters, neurobehavioural paradigms, mitochondrial respiration, neuronal architecture assessment were assessed.

KEY FINDINGS

QR and Mel restored the mitochondrial oxidative stress biomarkers in both the studies. Additionally, these nutraceuticals resuscitated the neurobehavioural alterations and restored the neuronal architecture alterations in TNPs exposed rats. The mitochondrial dysfunction induced by TNPs was also ameliorated by QR and Mel by protecting the mitochondrial complex activity and mitochondrial respiration rate.

SIGNIFICANCE

Results of the study demonstrated that QR and Mel ameliorated mitochondrial mediated neurotoxic effects induced by TNPs exposure.

Verapamil inhibits TXNIP-NLRP3 inflammasome activation and preserves functional recovery after intracerebral hemorrhage in mice

Intracerebral hemorrhage (ICH) is the second most common type of stroke with no satisfactory treatment. Recent studies from our group and others indicated a potential positive effect of verapamil, a commonly prescribed calcium channel blocker, with thioredoxin-interacting protein (TXNIP) inhibitor properties, in ischemic stroke and cognitive disorders. It is unclear whether there would be a beneficial effect of verapamil administration in ICH. Therefore, this study was designed to determine the neuroprotective effects of verapamil in a murine ICH model. ICH was induced by stereotactic injection of collagenase type VII (0.075 U) into the right striatum of adult male C57BL/6 mice. Verapamil (0.15 mg/kg) or saline was administered intravenously at 1 h post-ICH followed by oral (1 mg/kg/d) administration in drinking water for 28 days. Motor and cognitive function were assessed using established tests for motor coordination, spatial learning, short- and long-term memory. A subset of animals was sacrificed at 72 h after ICH for molecular analysis. Verapamil treatment reduced expression of TXNIP and NOD-like receptor pyrin domain-containing-3 inflammasome activation in the perihematomal area. These protective effects of verapamil were associated with decreased proinflammatory mediators, microglial activation, and blood-brain barrier permeability markers and paralleled less phosphorylated nuclear factor kappa B level. Our findings also demonstrate that long-term low-dose verapamil effectively attenuated motor and cognitive impairments. Taken together, these data indicate that verapamil has therapeutic potential in improving acute motor function after ICH. Further investigations are needed to confirm whether verapamil treatment could be a promising candidate for clinical trials.

Identification and in silico analysis of a spectrum of SLC4A11 variations in Indian familial and sporadic cases of congenital hereditary endothelial dystrophy

Background

Congenital hereditary endothelial dystrophy (CHED) is a rare form of corneal dystrophy caused by SLC4A11 gene variations. This study aims to find the genetic alterations in SLC4A11, in two Indian familial CHED cases with affected members n = 3 and n = 2 respectively and five sporadic CHED cases using direct sequencing, followed by in silico analysis and characterization of the identified variants.

Results

All three affected members of the first CHED family were identified with a novel homozygous c.1514C > G (p.Ser489Trp) variation while second family showed presence of a compound heterozygous variation c.529A > C (p.Arg161Arg) + c.2461insT (p.Val805fs). Among five sporadic cases, two showed novel changes, homozygous c.1487G > T (p.Ser480Ile) and c.620-2A > G, while the other one had previously reported homozygous c.2653C > T (p.Arg869Cys) variation. The remaining two cases did not reveal the presence of SLC4A11-related pathogenic variations. The identified variations were excluded from the Indian control (n = 80). In silico analysis using homology-based protein modeling and pathogenicity prediction tools, which revealed these alterations as pathogenic, changing their protein stability, local flexibility, residue contact clashes, and the hydrogen bond interactions.

Conclusions

This study contributed to the CHED mutational spectrum, adding four novel variations and confirming a previously reported one. It demonstrates different type of variations in CHED cases, including coding, non-coding, homozygous, synonymous, and compound heterozygous variations. The identified variations revealed different degrees of pathogenic effects in silico. Moreover, two sporadic cases could not be identified with pathogenic variation emphasizing the involvement of other genes or genetic mechanisms.

Targeting novel sites in DNA gyrase for development of anti-microbials

Antimicrobial resistance in bacteria poses major challenges in selection of the therapeutic regime for managing the infectious disease. There is currently an upsurge in the appearance of multiple drug resistance in bacterial pathogens and a decline in the discovery of novel antibiotics. DNA gyrase is an attractive target used for antibiotic discovery due to its vital role in bacterial DNA replication and segregation in addition to its absence in mammalian organisms. Despite the presence of successful antibiotics targeting this enzyme, there is a need to bypass the resistance against this validated drug target. Hence, drug development in DNA gyrase is a highly active research area. In addition to the conventional binding sites for the novobiocin and fluoroquinolone antibiotics, several novel sites are being exploited for drug discovery. The binding sites for novel bacterial type II topoisomerase inhibitor (NBTI), simocyclinone, YacG, Thiophene and CcdB are structurally and biochemically validated active sites, which inhibit the supercoiling activity of topoisomerases. The novel chemical moieties with varied scaffolds have been identified to target DNA gyrase. Amongst them, the NBTI constitutes the most advanced DNA gyrase inhibitor which are in phase III trial of drug development. The present review aims to classify the novel binding sites other than the conventional novobiocin and quinolone binding pocket to bypass the resistance due to mutations in the DNA gyrase enzyme. These sites can be exploited for the identification of new scaffolds for the development of novel antibacterial compounds.

Direct AT2R Stimulation Slows Post-stroke Cognitive Decline in the 5XFAD Alzheimer's Disease Mice

Alzheimer's disease (AD), currently the single leading cause of death still on the rise, almost always coexists alongside vascular cognitive impairment (VCI). In fact, the ischemic disease affects up to 90% of AD patients, with strokes and major infarctions representing over a third of vascular lesions. Studies also confirmed that amyloid plaques, typical of AD, are much more likely to cause dementia if strokes or cerebrovascular damage also exist, leading to the term "mixed pathology" cognitive impairment. Although its incidence is expected to grow, there are no satisfactory treatments. There is hence an urgent need for safe and effective therapies that preserve cognition, maintain function, and prevent the clinical deterioration that results from the progression of this irreversible, neurodegenerative disease. To our knowledge, this is the first study to investigate the effects of long-term treatment with C21, a novel angiotensin II type 2 receptor (AT2R) agonist, on the development of "mixed pathology" cognitive impairment. This was accomplished using a unique model that employs the fundamental elements of both AD and VCI. Treatment with C21/vehicle was started 1 h post-stroke and continued for 5 weeks in mice with concurrent AD pathology. Efficacy was established through a series of functional tests assessing various aspects of cognition, including spatial learning, short-term/working memory, long-term/reference memory, and cognitive flexibility, in addition to the molecular markers characteristic of AD. Our findings demonstrate that C21 treatment preserves cognitive function, maintains cerebral blood flow, and reduces Aβ accumulation and toxic tau phosphorylation in AD animals post-stroke.

New Frontier in the Management of Corneal Dystrophies: Basics, Development, and Challenges in Corneal Gene Therapy and Gene Editing

ABSTRACT

Corneal dystrophies represent a group of heterogeneous hereditary disorders causing progressive corneal opacification and blindness. Current corneal transplant management for corneal dystrophies faces the challenges of repeated treatments, complex surgical procedures, shortage of appropriate donor cornea, and, more importantly, graft rejection. Genetic medicine could be an alternative treatment regime to overcome such challenges. Cornea carries promising scope for a gene-based therapy involving gene supplementation, gene silencing, and gene editing in both ex vivo and in vivo platforms. In the cornea, ex vivo gene therapeutic strategies were attempted for corneal graft survival, and in vivo gene augmentation therapies aimed to prevent herpes stromal keratitis, neovascularization, corneal clouding, and wound healing. However, none of these studies followed a clinical trial-based successful outcome. CRISPR/Cas system offers a broad scope of gene editing and engineering to correct underlying genetic causes in corneal dystrophies. Corneal tissue--specific gene correction in vitro with minimal off-target effects and optimal gene correction efficiency followed by their successful surgical implantation, or in vivo CRISPR administration targeting pathogenic genes finds a way to explore therapeutic intervention for corneal dystrophies. However, there are many limitations associated with such CRISPR-based corneal treatment management. This review will look into the development of corneal gene therapy and CRISPR-based study in corneal dystrophies, associated challenges, potential approaches, and future directions.

Spread of Mesalazine Rectal Foam after Single Dose in Mild Ulcer Patients

Background: The rectal foam enemas were used for ulcerative colitis of distal regions due to its desired efficacy and less side effects. The spread and persistence of the drug plays a key role in the treatment. Therefore, the objective of the present study is to study the spread and persistence of Salofalk (Mesalazine foam Enema), manufactured by Dr. Falk Pharma GmbH (mesalazine) rectal foam in mild ulcerative colitis patients. Methods: This is an open label, uncontrolled prospective study in ulcerative colitis patients. The patients received 2 g of mesalazine rectal foam (labelled with Tcm99) in two actuations (30 mL). The spread of the radiolabeled formulation was assessed over a period of 4 h by gamma scintigraphy. Results: The formulation was retained by the patients till 4 h imaging period. The foam spread in rectum, sigmoid colon and descending colon. The percentage radioactive dose exposed is more in sigmoid colon compared to rectum and descending colon in 4 h imaging period. The spread of the foam extended till descending colon for two out of 4 patients. Conclusion: The study results are consistent with the previous studies, and it supports the label indication. The obtained data of the present study provides in vivo evidence of the spread of formulation in the desired site of action.

Reproductive performance following hysteroscopic treatment of intrauterine adhesions: single surgeon data

Background

Intrauterine adhesions can negatively affect reproductive outcomes by causing infertility, miscarriage and preterm birth in women. Hysteroscopic surgery is now widely accepted as the treatment of choice in symptomatic women to restore reproductive function.

Objectives

To analyse the patient characteristics and long-term reproductive outcomes of women who received treatment for intrauterine adhesions under the care of a single surgeon.

Materials and Methods

In this retrospective analysis, all women who underwent hysteroscopic surgery for intrauterine adhesions under the care of the same surgeon between January 2001 and December 2019 were identified and their data were evaluated. Relevant demographic, diagnostic and reproductive outcome data was procured from patient notes. Referring doctors and patients were contacted to obtain missing information.

Main outcome measures

Live birth and miscarriage rates.

Results

126 women were treated for intrauterine adhesions. Of those women who were trying to conceive, 71.4% (65/91) achieved pregnancy, 58.2% (53/91) had live births and 13.2% (12/91) had miscarriages. No statistically significant difference was found in the live birth rates when data was analysed in subgroups based on age, reason for referral/aetiology and severity of pathology.

Conclusions

Hysteroscopic surgery leads to live birth in the majority of women with intrauterine adhesions. The lack of statistically significant difference in live birth rates across subgroups, including advanced age and severe pathology, suggests that surgery in all women wanting to conceive can be justified.

What is new?

Hysteroscopic treatment can lead to successful outcomes even in the presence of severe adhesions and in older women with appropriate treatment.

259 Effect of Telegram Videos on Anatomy Education Among 2nd Year Medical Students, University of Khartoum, 2021

Aim

COVID-19 had major effect on the health and medical education. In order to oblige with the social distancing and quarantine, universities shifted to online learning. This study aimed to assess the effect of online education on anatomy DR (dissection room) teaching by the use of telegram software.

Method

This was a cross-sectional, prospective interventional study, which was carried out among 2nd year medical students in University of Khartoum. Students undertook initial tests on the heart and anterior abdominal wall modules. Telegram videos, prepared by the author, on the anatomy of the heart and the anterior abdominal wall were distributed to students. Students took a second test after watching the videos. A total number of 41 students attended heart sessions and 40 students attended the anterior abdominal wall sessions were included.

Results

The pre-test mean score for the heart and abdomen modules were 4.56 ± 2.335 and 6.15 ± 2.94, respectively. The post-tests means were 9.98 ± 2.877 and 8.95 ± 3.14, respectively. 90% and 75% of the students were satisfied with these videos, respectively.

Conclusions

This study revealed that Telegram videos as a method of online teaching had a positive effect on the students' performance, which was evidenced by the significant improvement in student's scores after watching the videos. Additionally, most of the students were satisfied with the videos and give positive feedback.

Identification of polypharmacological anticancerous molecules against Aurora kinase family of proteins

The Human Aurora Kinase (AURK) protein family is the key player of cell cycle events including spindle assembly, kinetochore formation, chromosomal segregation, centrosome separation, microtubule dynamics, and cytokinesis. Their aberrant expression has been extensively linked with chromosomal instability in addition to derangement of multiple tumor suppressors and oncoprotein regulated pathways. Therefore, the AURK family of kinases is a promising target for the treatment of various types of cancer. Over the past few decades, several potential inhibitors of AURK proteins have been identified and have reached various phases of clinical trials. But very few molecules have currently crossed the safety criteria due to their various toxic side effects. In the present study, we have adopted a computational polypharmacological strategy and identified four novel molecules that can target all three AURKs. These molecules were further investigated for their binding stabilities at the ATP binding pocket using molecular dynamics based simulation studies. The molecules selected adopting a multipronged computational approach can be considered as potential AURKs inhibitors for cancer therapeutics.

Meningitis following cerebrospinal fluid-cutaneous fistula secondary to combined spinal-epidural anaesthesia for elective caesarean delivery

Cerebrospinal fluid-cutaneous fistula is a rare complication associated with neuraxial procedures. Here, we describe a case of fistula formation related to combined spinal-epidural anaesthesia for elective caesarean delivery, where the epidural catheter was removed only two hours later. The clear fluid leaking persistently from the site of the skin puncture associated with the epidural insertion site was confirmed to be cerebrospinal fluid with an increased beta-trace protein, and the fistula was closed with skin sutures. Subsequently, the patient presented with neurological signs and symptoms consistent with meningitis and she was treated empirically with intravenous antibiotics. Cerebrospinal fluid-cutaneous fistula formation with secondary meningitis is an exceptionally rare event in obstetric anaesthesia.

1255 Crowdedness and Consequences of Long Waiting Time in Public and Private Health Centers Among Patients in Khartoum State, Sudan - 2016

Aim

Waiting time (WT) reflects quality of services delivered by Primary health care level. Long waiting time is due to various causes, among which crowdedness is a main cause. This prolonged time has negative impacts on PHC services utilization as well as patients’ outcomes. The aim of this study is to measure the total WT, assess the crowdedness in PHC centers, and to determine the possible consequences of this long waiting time.

Method

Descriptive cross sectional– health institution-based study done in 40 Health centres across Khartoum state using randomized multi-stage sampling. Patients, doctors and lab technicians were interviewed using three different pre-tested structured questionnaires.

Results

A total of 477 patients were included in the study. The average waiting time was found to be 168 minutes. Crowdedness was one of the main causes of delay in waiting time. The lab was the most perceived crowded service (74.4% of the respondents). This long WT had health consequences on patients, ranging from backache, joint pain, and headaches to hypoglycemic symptoms. These symptoms affected patients' willingness to return to the same center. 36.4% of the affected patients were unwilling to revisit the same center.

Conclusions

WT in this study is longer compared to studies from other countries. Crowdedness is one of the main causes of long WT. Due to this prolonged time, patients experienced physical symptoms. It also affected their future attitude regarding PHC centers utilization. There is a need to understand the underlying causes of this issue and address them appropriately.

Unusual presentation of an insulinoma in an elderly male patient

Insulinoma is a rare neuroendocrine tumor originating from hypersecreting beta-cells of islets of Langerhans in the pancreas. We report a case of 72-year-old male, with chronic alcohol abuse, presenting with atypical features like refractory recurrent secondary generalized seizures and behavioral disturbances with increased irritability, initially mistreated as alcohol withdrawal. Detailed history, particularly the relationship of the symptoms with food intake, made us think of other causes of seizures. Fasting biochemical investigations and localizing studies helped clinch the diagnosis. The tumor was localized with the help of endoscopic ultrasonography and whole-body Ga68-DOTANOC PET-CT. The patient was treated conservatively with diazoxide and is doing well on follow-up. The present case report emphasizes the importance of detailed clinical history, more so in atypically presenting cases of refractory seizures. Insulinoma can be medically managed despite surgery being the gold standard curative treatment.

Harnessing the mitochondrial integrity for neuroprotection: Therapeutic role of piperine against experimental ischemic stroke

Ischemic stroke (IS) is a rapidly increasing global burden and is associated with severe neurological decline and mortality. There is urgent requirement of the efforts, aimed to identify therapeutic strategies that are effective in clinic to promote significant recovery from IS. Studies have shown that mitochondria mediated neuroprotection can be a competent target against ischemic damage. Therefore, we examined whether mitochondrial impairment is regulated by Piperine (PIP), an alkaloid of Piper Longum, which has neuroprotective activity against ischemic brain injury. In this study, transient middle cerebral artery occlusion (tMCAO) surgery was performed on male Wistar rats for 90 min followed by 22.5 h of reperfusion for mimicking the IS condition. This study consisted of three groups: sham, tMCAO and tMCAO + PIP (10 mg/kg b.wt., p.o/day for 15 days), and studied for behavioral tests, infarct volume, brain pathological changes, mitochondrial dysfunction, inflammation alongwith cell survival status. PIP pre-treatment showed reduction in neurological alterations and infarct volume. In addition, PIP pre-treatment suppressed the mitochondrial dysfunction and might have anti-apoptotic potential by preventing Cytochrome c (Cyt c) release from mitochondria to cytoplasm and caspase 3 activation. It also regulates pro-apoptotic, Bax and anti-apoptotic, Bcl-2 proteins accompanied by glial fibrillary acidic protein (GFAP) positive cells in cortex region. Quantitative Reverse transcription-polymerase chain reaction (qRT-PCR) results also showed that PIP reduced the expression of pro-inflammatory protein, interleukin-1 β (IL-1β) and enhanced cell survival by restoring the activity of brain derived neurotrophic factor (BDNF) and its transcription protein, cAMP response element binding protein (CREB). Taken together, PIP reduced the mitochondrial dysfunction, neurological impairment, and enhanced neuronal survival. In conclusion, our findings reinforce PIP as an effective neuroprotective agent and provide important evidence about its role as a potential target to serve as a promising therapy for treatment of IS.

388 Detection of Cytomegalovirus Infection in Infants with Biliary Atresia: A Meta-analysis

Introduction

Biliary atresia (BA) is the most common indication of liver transplantation in children. Several reports attributed BA to both prenatal and perinatal aetiologies, including a viral infection-induced auto-immune response that targets the bile ducts. Cytomegalovirus (CMV) remains the most common virus being linked to BA. This meta-analysis estimates to what extent CMV infection is detected in patients with BA.

Method

This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The databases of MEDLINE/PubMed, WHO-Virtual Health Library (VHL), ScienceDirect, and Google Scholar were used for the systematic search. Random effects model was used to estimate the pooled prevalence estimate with the corresponding 95% confidence interval (CI) using StatsDirect statistical software.

Results

A total of 13 studies (covering 419 patients) that fulfilled the eligibility criteria were included in the meta-analysis. The pooled overall prevalence of CMV infection in patients with BA was 24.5% (95% CI 11.9 %– 33.9%).

Conclusions

The available data demonstrate that the detection of CMV infection is common in infants with BA. There is still a need for large studies with appropriate controls to examine various aspects of the association between CMV infection and BA.

Melatonin Provides Neuroprotection Following Traumatic Brain Injury-Promoted Mitochondrial Perturbation in Wistar Rat

Excessive mitochondrial fission has been implicated in the etiology of neuronal cell death in traumatic brain injury (TBI). In the present study, we examined the efficacy of melatonin (Mel) as a neuroprotective agent against TBI-induced oxidative damage and mitochondrial dysfunction. We assessed the impact of Mel post-treatment (10 mg/kg b.wt., i.p.) at different time intervals in TBI-subjected Wistar rats. We found that the Mel treatment significantly attenuated brain edema, oxidative damage, mitochondrial fission, and promoted mitochondrial fusion. Additionally, Mel-treated rats showed restoration of mitochondrial membrane potential and oxidative phosphorylation with a concomitant reduction in cytochrome-c release. Further, Mel treatment significantly inhibited the translocation of Bax and Drp1 proteins to mitochondria in TBI-subjected rats. The restorative role of Mel treatment in TBI rats was supported by the mitochondrial ultra-structural analysis, which showed activation of mitochondrial fusion mechanism. Mel enhanced mitochondrial biogenesis by upregulation of PGC-1α protein. Our results demonstrated the remedial role of Mel in ameliorating mitochondrial dysfunctions that are modulated in TBI-subjected rats and provided support for mitochondrial-mediated neuroprotection as a putative therapeutic agent in the brain trauma.

Naringenin mitigates behavioral alterations and provides neuroprotection against 3-nitropropinoic acid-induced Huntington's disease like symptoms in rats

BACKGROUND

Naringenin is a powerful antioxidant and anti-inflammatory flavonoid which has been widely used as a therapeutic agent in various toxic models. However, few studies have clearly discussed the neuromodulatory effects of naringenin against different neurodegenerative disorders.

AIM

We investigated the neuroprotective efficacy of naringenin against 3-nitropropionic acid (3-NP)-induced neurobehavioral, biochemical and histopathological alterations in rats.

METHODS

Albino Wistar rats were randomly divided into three experimental groups. Group 1, the vehicle administered group, received saline. Group 2 received 3-NP (20 mg/kg body weight, i.p.) for 4 consecutive days. Group 3 received naringenin (50 mg/kg body weight, p.o.) twice daily for a period of 4 days, 30 min before and 6 h after the 3-NP administration. On the 5th day, neurobehavioral experiments were performed to access the behavioral outcomes and the striatum tissue was used for analysis of the monoamine oxidase (MAO) activity and serotonin (5-HT) levels. In addition, astrocytes activation was observed by glial fibrillary acidic protein (GFAP) immunostaining.

RESULTS

Our results showed that naringenin co-treatment provides neuroprotection against 3-NP-induced neurological disorders. Naringenin also increased the MAO activity and 5-HT levels in the striatum. Moreover, co-treatment with naringenin reduced the expression of GFAP protein in the striatal part and significantly attenuated the neuronal cell death. The findings of the present study suggest that naringenin provides neuroprotection and mitigates neurobehavioral alterations in experimental rats.

CONCLUSION

The results show that co-treatment with naringenin ameliorates 3-NP-induced HD-like symptoms in rats.

Effect of vitamin A as a neoadjuvant agent in chemotherapy and photodynamic therapy of Rhabdomyosarcoma cells

Combinational therapy is among the most used treatment modality's to increase cancer treatment efficacy. It may also reduce side effects, treatment time, and development of drug resistance. The effects of different analogues of vitamin A (VA) as neoadjuvant agent were observed in this study with chemotherapeutic drugs (doxorubicin and methotrexate) and photodynamic therapy (PDT) using 5-ALA and Photogem as photosensitizers in RD cells. The uptake time of photosensitizer was optimized by means of spectrophotometric measurements. Diode laser (λ = 635 nm ± 1 nm) was used as an illumination source for PDT. Responses of administered drugs were assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. VA and its analogues exert prophylactic and therapeutic effects. Protective or antagonistic effects (CI > 1) were observed in each of the case. These results propose that the use of VA as a neoadjuvant agent in combinational therapeutic modalities may reduce the efficacy of cancer treatment protocols as well as the existing side effects. Thus, VA is not the successful drug for combinational therapies and under treatment cancer patients should try to avoid its use with oxidative stress induction therapies (e.g. PDT, Radiotherapy, chemotherapy).

Tempol (4-hydroxy tempo) protects mice from cisplatin-induced acute kidney injury via modulation of expression of aquaporins and kidney injury molecule-1

Tempol (4-hydroxy tempo), a pleiotropic antioxidant is reported to afford protection against cisplatin (CP)-induced nephrotoxicity. However, molecular mechanisms of action of tempol in improving the renal function in CP-induced nephrotoxicity are not fully understood. We investigated the attenuating effect of tempol against CP-induced alterations in kidney injury molecule-1 (KIM-1) and aquaporins (AQPs) in mice. Tempol (100 mg/kg, po) pretreatment with CP (20 mg/kg ip) showed restoration in renal function markers including electrolytes. CP treatment upregulated mRNA expression of KIM-1 and downregulated AQP and arginine vasopressin (AVP) expression which was attenuated by tempol. Immunoblotting analysis revealed that CP-induced alterations in KIM-1 and AQP expression were restored by tempol. Immunofluorocense study also showed restorative effect of tempol on the expression of AQP2 in CP-treated mice. In conclusion, this study provides experimental evidence that tempol resolved urinary concentration defect by the restoration of AQP, AVP and KIM-1 levels indicating a potential use of tempol in ameliorating the AKI in cancer patients under the treatment with CP.

Alogliptin reversed hippocampal insulin resistance in an amyloid-beta fibrils induced animal model of Alzheimer's disease

The complications of Alzheimer's disease (AD) have made the development of its treatment a challenging task. Several studies have indicated the disruption of insulin receptor substrate-1 (IRS-1) signaling during the development and progression of AD. The role of a dipeptidyl peptidase-4 (DPP-4) inhibitor on hippocampal IRS-1 signaling has not been investigated before. In this study, we evaluated the efficacy of alogliptin (DPP-4 inhibitor) on hippocampal insulin resistance and associated AD complications. In the present study, amyloid-β (1-42) fibrils were produced and administered intrahippocampally for inducing AD in Wistar rats. After 7 days of surgery, rats were treated with 10 and 20 mg/kg of alogliptin for 28 days. Morris water maze (MWM) test was performed in the last week of our experimental study. Post 24 h of final treatment, rats were euthanized and hippocampi were separated for biochemical and histopathological investigations. In-silico analysis revealed that alogliptin has a good binding affinity with Aβ and beta-secretase-1 (BACE-1). Alogliptin significantly restored cognitive functions in Aβ (1-42) fibrils injected rats during the MWM test. Alogliptin also significantly attenuated insulin level, IRS-1pS307 expression, Aβ (1-42) level, GSK-3β activity, TNF-α level and oxidative stress in the hippocampus. The histopathological analysis supported alogliptin mediated neuroprotective and anti-amyloidogenic effect. Immunohistochemical analysis also revealed a reduction in IRS-1pS307 expression after alogliptin treatment. The in-silico, behavioral, biochemical and histopathological analysis supports the protective effect of alogliptin against hippocampal insulin resistance and AD.

Nrf2/HO-1 mediates the neuroprotective effects of pramipexole by attenuating oxidative damage and mitochondrial perturbation after traumatic brain injury in rats

Pramipexole (PPX), a D2-like receptor agonist, is generally used in the treatment of Parkinson's disease and restless leg syndrome. Its neuroprotective effects have been shown against various neurological disorders. Recent research work has demonstrated that PPX exerts neuroprotection through mitochondria. However, the neuromodulator-related effects of PPX against traumatic brain injury (TBI) remain unexplored. The present study, therefore, investigated the mechanism of neuroprotection by PPX against oxidative stress, mitochondrial dysfunction and neuronal damage following TBI in rats. We hypothesized that the neuroprotection by PPX in TBI-subjected rats might involve activation of the Nrf2/HO-1 (also known as Nfe2l2/Hmox1) signaling pathway. PPX was injected intraperitoneally (0.25 mg/kg body weight and 1.0 mg/kg body weight) at different time intervals post-TBI. Several neurobehavioral parameters were assessed at 48 h post-TBI, and the brain was isolated for molecular and biochemical analysis. The results demonstrated that PPX treatment significantly improved the behavioral deficits, decreased the lipid peroxidation rate, increased glutathione levels and decreased 4-hydroxynonenal levels in TBI-subjected rats. PPX also increased the activities of glutathione peroxidase and superoxide dismutase enzymes. In addition, PPX treatment inhibited mitochondrial reactive oxygen species production, restored mitochondrial membrane potential and increased ATP levels after a TBI. Further, PPX treatment reduced the Bax/Bcl2 ratio and translocation of Bax to mitochondria and cytochrome-c to the cytosol. Finally, PPX treatment greatly accelerated the translocation of Nrf2 to the nucleus and upregulated HO-1 protein expression. We conclude that the neuroprotective effects of PPX are mediated by activation of the Nrf2/HO-1 signaling pathway following TBI.This article has an associated First Person interview with the first author of the paper.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Stability-indicating RP-HPLC assay for simultaneous determination of chlorpheniramine maleate and prednisolone in veterinary injection

The present work described a simple, rapid, sensitive, accurate, and precise method for simultaneous determination of chlorpheniramine maleate (CHRM) and prednisolone acetate (PRED) in injection samples by high-performance liquid chromatography (HPLC) coupled with UV–Vis detection. Chromatographic separation was accomplished, employing isocratic mode and a mobile phase comprised of acetonitrile and a phosphate buffer (50:50, v/v, 30 °C), adjusted to pH 3.0. The flow rate used was 1.0 mL/min on a Thermo Hypersil ODS C18 column (5 μm, 4.6 × 250 mm), and the injection volume of sample was 20 μL. Analysis of CHRM and PRED was performed at a wavelength of 254 nm. The runtime for analysis was 12.5 min, and the retention times of CHRM and PRED were found to be 2.81 and 5.07 min, respectively. The calibration graph showed linearity over the concentration range 10–70 μg/mL for CHRM and 20–140 μg/mL for PRED with a coefficient of determination (R2) ≥0.9986. Repeatability and reproducibility (expressed as % RSD) were lower than 1.72 and 1.47%, respectively. The proposed HPLC method was demonstrated to be simple and rapid for the determination of CHRM and PRED in injection formulation, providing recoveries between 101.6–102.3%, whereas complete separation of degradation products, from analyte under investigation, provided the specificity of the proposed HPLC method.

Tannic Acid Provides Neuroprotective Effects Against Traumatic Brain Injury Through the PGC-1α/Nrf2/HO-1 Pathway

The present research was conducted to elucidate a possible molecular mechanism related to neuromodulatory effects of tannic acid (TA) supplementation against traumatic brain injury (TBI) in a rodent model. Oxidative damage and neuroinflammation play a critical role in TBI and lead to behavioral alterations and neuronal dysfunction and death. These changes suggest a potential avenue in neurotherapeutic intervention. The aim of the present study was to investigate the neuroprotective effects of TA and potential mechanism of these effects in a controlled cortical impact injury model of TBI in Wistar rats that were treated with TA (50 mg/kg body weight. i.p.) before 30 min and 6 and 18 h after TBI. TBI-induced rats were examined after 24 h for behavioral dysfunction, Nissl stain, lipid peroxidation rate, glutathione level, activities of antioxidant enzymes (catalase, glutathione S-transferase, glutathione peroxidase, and superoxide dismutase), the expression level of 4-hydroxynonenal, pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin-1 beta, as well as brain edema and immunoreactivity of glial fibrillary acidic protein. Results indicated that TA supplementation significantly modulated above mentioned alterations. Moreover, TA treatment effectively upregulated the protein expression of peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1α) and nuclear factor-E2-related factor-2 (Nrf2) as well as mitochondrial transcription factor A and heme oxygenase-1 (HO-1) following TBI. Overall, our results suggest that TA effectively ameliorates the behavioral alterations, oxidative damage, mitochondrial impairment, and inflammation against TBI that may be attributed to activation of PGC-1α/Nrf-2/HO-1 signaling pathway.

Chlorogenic acid attenuates kidney fibrosis via antifibrotic action of BMP-7 and HGF

BACKGROUND

Kidney fibrosis, characterised by tubulointerstitial fibrosis, is a histological landmark of chronic kidney disease. The body attempts to compensate for progressive detrimental process of kidney fibrosis by producing antifibrotic substances, such as bone morphogenetic protein-7 (BMP-7) and hepatocyte growth factor (HGF). Chlorogenic acid is known to have renoprotective and antifibrotic properties. This study aims to evaluate the effect of chlorogenic acid on unilateral ureteral obstruction (UUO)-induced kidney fibrosis mice model.

METHODS

This study was a quasi-experimental with posttestonly control group design. Twenty-five adult male Swiss Webster mice were randomly divided into five groups: shamoperated group (SO), UUO-control day-7 (U7), UUO-control day-14 (U14), UUO-chlorogenic acid day-7 (UC7), and UUOchlorogenic acid day 14 (UC14). Myofibroblasts were identified by immunohistochemical staining of alphasmooth muscle actin (α-SMA) while collagen fibers were identified by Sirius Red staining. Both data were presented as area fraction. BMP-7 and HGF mRNA expressions were assessed by reverse transcription PCR (RT-PCR). Data were quantified using ImageJ software.

RESULTS

UUO-control groups (U7 and U14) showed higher α- SMA-immunopositive (6.52±1.33, 18.24±1.39 vs. 0.22±0.01; p<0.05) and Sirius Red-positive area fractions (6.61±0.8, 12.98±2.31 vs. 0.62±0.10; p<0.05), lower BMP-7 (1.02±0.47, 1.18±0.65 vs. 2.09±0.87; p<0.05) and HGF mRNA expressions (1.06±0.31, 0.89±0.14 vs. 1.88±0.81; p<0.05) compared to SO group. UUO-chlorogenic acid groups (UC7 and UC14) showed lower α-SMA-immunopositive (1.24±0.37, 4.58±0.61; p<0.05) and Sirius Red-positive area fractions (4.76±1.03, 3.72±0.54; p<0.05), higher BMP-7 (1.84±0.49, 2.19±0.43; p<0.05) and HGF (1.58±0.38; p>0.05, 1.84±0.42; p<0.05) mRNA expressions compared to UUO-control groups. UUOchlorogenic acid groups showed BMP-7 and HGF mRNA expressions that were not significantly different from the SO group.

CONCLUSION

Chlorogenic acid administration prevents kidney fibrosis in UUO mice model through modulating antifibrotic pathway.

A multicentre, randomized, double-masked, parallel group, vehicle-controlled phase IIb study to evaluate the safety and efficacy of 1% and 3% topical minocycline gel in patients with papulopustular rosacea

Background

Papulopustular rosacea is characterized by chronic facial erythema and inflammatory facial lesions. Minocycline has anti‐inflammatory properties which may be effective in the treatment of rosacea inflammatory lesions.

Objectives

To assess the safety and efficacy of once‐daily topical minocycline gel 1% and 3% in patients with papulopustular rosacea.

Methods

This was a prospective, 12‐week, double‐blinded study conducted at 26 sites in the United States; 270 patients with papulopustular rosacea and 12–40 inflammatory lesions were randomized to minocycline 1%, minocycline 3% or vehicle. The primary endpoint was the mean change in inflammatory lesions at week 12. Key secondary endpoints included success on an Investigator's Global Assessment (IGA).

Results

Baseline mean lesion counts were 24·6, 25·1 and 24·3 in the minocycline 1%, minocycline 3% and vehicle groups, respectively; at week 12, the counts had decreased by 12·6, 13·1 and 7·9, respectively. Minocycline significantly decreased lesions, compared with the vehicle [P = 0·01, 95% confidence interval (CI) 7·9 to 0·9, for minocycline 1%; P = 0·007, 95% CI 8·3 to 1·3, for minocycline 3%]. The proportion of patients achieving IGA success was 39% in the minocycline 1% arm [P = 0·34, odds ratio (OR) 1·396 and OR 95% CI 0·71 to 2·75 vs. vehicle], 46% in the minocycline 3% arm (P = 0·04, OR 2·03 and OR 95% CI 1·04 to 3·95 vs. vehicle) and 31% in the vehicle arm.

Conclusions

Minocycline topical gel appears to be safe and tolerable at concentrations of 1% and 3%, and both concentrations significantly decreased inflammatory lesion counts, with a significantly larger proportion of patients achieving IGA success at week 12 in the minocycline 3% arm. These findings support further evaluation of minocycline gel for treating inflammatory lesions associated with papulopustular rosacea.

Linked Comment: Hampton. Br J Dermatol 2020; 183:412–413.

What is already known about this topic?

Papulopustular rosacea is characterized by inflammatory facial lesions and chronic erythema of the face.

Oral minocycline has been reported to have efficacy in the treatment of inflammatory lesions of papulopustular rosacea.

What does this study add?

The study shows that a topical gel preparation of minocycline significantly decreased the number of inflammatory lesions and significantly improved the Investigator's Global Assessment score in patients with papulopustular rosacea.

This may offer a topical therapeutic alternative to oral doxycycline or oral minocycline for the treatment of inflammatory lesions in papulopustular rosacea, with potentially fewer systemic side‐effects, owing to lower systemic drug exposure.

Linked Comment: Hampton. Br J Dermatol 2020; 183:412–413.

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