Animal Studies Research Articles

Luciferase-Decorated Gold Nanorods as Dual-Modal Contrast Agents for Tumor-Targeted High-Performance Bioluminescence/Photoacoustic Imaging.

Gold nanorods (AuNRs) have been considered highly compelling materials for early cancer diagnosis and have aroused a burgeoning fascination among the biomedical sectors. By leveraging the versatile tunable optical properties of AuNRs, herein, we have developed a novel tumor-targeted dual-modal nanoprobe (FFA) that exhibits excellent bioluminescence and photoacoustic imaging performance for early tumor diagnosis. FFA has been synthesized by anchoring the recombinant bioluminescent firefly luciferase protein (Fluc) on the folate-conjugated AuNRs via the PEG linker. TEM images and UV-vis studies confirm the nanorod morphology and successful conjugation of the biomolecules to AuNRs. The nanoprobe FFA relies on the ability of the folate module to target the folate receptor-positive tumor cells actively, and simultaneously, the Fluc module facilitates excellent bioluminescent properties in physiological conditions. The success of chemical engineering in the present study enables stronger bioluminescent signals in the folate receptor-positive cells (Skov3, Hela, and MCF-7) than in folate receptor-negative cells (A549, 293T, MCF-10A, and HepG2). Additionally, the AuNRs induced strong photoacoustic conversion performance, enhancing the resolution of tumor imaging. No apparent toxicity was detected at the cellular and mouse tissue levels, manifesting the biocompatibility nature of the nanoprobe. Prompted by the positive merits of FFA, the in vivo animal studies were performed, and a notable enhancement was observed in the bioluminescent/photoacoustic intensity of the nanoprobe in the tumor region compared to that in the folate-blocking region. Therefore, this synergistic dual-modal bioluminescent and photoacoustic imaging platform holds great potential as a tumor-targeted contrast agent for early tumor diagnosis with high-performance imaging information.

Current trends in the prevention of adhesions after zone 2 flexor tendon repair.

Treating flexor tendon injuries within the digital flexor sheath (commonly referred to as palmar hand zone 2) presents both technical and logistical challenges. Success hinges on striking a delicate balance between safeguarding the surgical repair for tendon healing and initiating early rehabilitation to mitigate the formation of tendon adhesions. Adhesions between tendon slips and between tendons and the flexor sheath impede tendon movement, leading to postoperative stiffness and functional impairment. While current approaches to flexor tendon repair prioritize maximizing tendon strength for early mobilization and adhesion prevention, factors such as pain, swelling, and patient compliance may impede postoperative rehabilitation efforts. Moreover, premature mobilization could risk repair failure, necessitating additional surgical interventions. Pharmacological agents offer a potential avenue for minimizing inflammation and reducing adhesion formation while still promoting normal tendon healing. Although some systemic and local agents have shown promising results in animal studies, their clinical efficacy remains uncertain. Limitations in these studies include the relevance of chosen animal models to human populations and the adequacy of tools and measurement techniques in accurately assessing the impact of adhesions. This article provides an overview of the clinical challenges associated with flexor tendon injuries, discusses current on- and off-label agents aimed at minimizing adhesion formation, and examines investigational models designed to study adhesion reduction after intra-synovial flexor tendon repair. Understanding the clinical problem and experimental models may serve as a catalyst for future research aimed at addressing intra-synovial tendon adhesions following zone 2 flexor tendon repair.

Influence of the use of bisphosphonates on the development of postextraction sequelae: scoping review with mapping evidence of in vivo studies.

To map the current scientific landscape regarding the association/causality of medication-related osteonecrosis of the jaw (MRONJ) after tooth extraction under bisphosphonate (BF) therapy to identify knowledge gaps and guide future research. This review used the PCC strategy (P = Patient; C = Concept; C = Context). The MEDLINE/PubMed, Scopus, Web of Science/Clarivate Analytics, and gray literature databases were used. Searches were conducted by two independent reviewers until April 2024. Studies involving prior BF use and tooth extraction in humans or animals were included. Among the 176 studies, 73 (41.4%) were in animals, and 103 (58.5%) were in humans. Brazil led in animal studies (n=14; 19.1%), while Italy led in human studies (n=14; 13.6%). Zoledronic acid was the most cited BF (79.4% in animals; 34.9% in humans), with intravenous administration being most frequent (38.3% in animals; 35.9% in humans). The mandible was the main extraction site (n=36 in animals; n=41 in humans). In 91.7% of the animal studies, sequelae compatible with osteonecrosis signs and symptoms were observed, with bone necrosis being most common (n=39; 53.4%). In humans, 93.2% of studies presented 239 sequelae, with bone necrosis (n=53; 22.1%) being the most cited. The main location of sequelae was the mandible (n=36 in animals; n=41 in humans). Animal studies highlighted bone exposure, notably using murine models, with a significant Brazilian contribution. In human studies, bone necrosis was the main sequela of MRONJ, which has been reported by researchers in the Italy. These findings underscore the importance of careful consideration and monitoring of patients who have a history of bisphosphonate use and who are undergoing tooth extraction, highlighting the potential risk of MRONJ.

Fat intravasation, fat emboli and fat embolism syndrome in adult major trauma patients with intraosseous catheters: a systematic review.

Intraosseous (IO) administration of medication, fluids and blood products is accepted practice for critically injured patients in whom intravenous access is not immediately available. However, there are concerns that high intramedullary pressures resulting from IO infusion may cause bone marrow intravasation and subsequent fat embolisation. The aim of this systematic review is to synthesise the existing evidence describing fat intravasation, fat embolism and fat embolism syndrome (FES) following IO infusion. A systematic search of CINAHL, MEDLINE and Embase was undertaken using the search terms "intraosseous", "fat embolism", "fat intravasation" and "fat embolism syndrome". Two authors independently screened abstracts and full texts, against eligibility criteria and assessed risk of bias. A grey literature search (including references) was undertaken. Inclusion criteria were: all human and animal studies reporting novel data on IO-associated fat emboli. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. 22 papers were identified from the search, with a further 5 found from reference lists. N=7 full papers met inclusion criteria. These papers were all translational animal studies. The overall risk of bias was high. Studies demonstrated that fat intravasation and fat embolisation are near universal after IO infusion, but of uncertain clinical significance. The initial IO flush appears to cause the highest intramedullary pressure and highest chance of fat intravasation and embolisation. No conclusions could be drawn on FES. IO catheters remain a useful intervention in the armamentarium of trauma clinicians. Although their use is widely accepted, there is a paucity of evidence investigating fat embolisation in IO infusions. Despite this, pulmonary fat emboli after IO infusion are very common. The existing data are of low quality with a high risk of bias. More research is needed to address this important subject. CRD42023399333.

Neurobrucellosis (Brucella ceti) in striped dolphins (Stenella coeruleoalba): Immunohistochemical studies on immune response and neuroinflammation.

Neurobrucellosis is a shared condition of cetaceans and humans. However, the pathogenesis and immune response in cetacean neurobrucellosis has not been extensively studied. In this multicentric investigation, 21 striped dolphin (Stenella coeruleoalba) neurobrucellosis (Brucella ceti) cases diagnosed over a 10-year period (2012-2022) were retrospectively evaluated. For each case, morphological changes were assessed by evaluating 21 histological parameters. Furthermore, the immunohistochemical expression of Brucella antigen, glial fibrillary acid protein (GFAP), and a selection of inflammatory cell (IBA-1, CD3, and CD20) and cytokine (tumor necrosis factor-alpha [TNF-α], interferon-gamma [IFN-γ], interleukin [IL]-1β, IL-2, and IL-6) markers were investigated. Inflammation of the leptomeninges, ependyma, and/or choroid plexus was lymphohistiocytic, containing macrophages/microglia (IBA-1+), T-cells (CD3+), and B-cells (CD20+) in equal proportion. B-cells occasionally formed tertiary follicles. GFAP expression showed astrocytosis in most cases. Expression of TNF-α, IFN-γ, and IL-2 indicated an intense proinflammatory response, stimulating both macrophages and T-cells. Our results showed that the inflammation and neuroinflammation in neurobrucellosis of striped dolphins mimic human neurobrucellosis and in vitro and in vivo studies in laboratory animals. Cetacean disease surveillance can be exploited to expand the knowledge of the pathogenesis and immunology of infectious diseases, particularly brucellosis, under a One Health approach.

Involvement of the contralateral hippocampus in ictal-like but not interictal epileptic activities in the kainate mouse model of temporal lobe epilepsy.

Animal and human studies have shown that the seizure-generating region is vastly dependent on distant neuronal hubs that can decrease duration and propagation of ongoing seizures. However, we still lack a comprehensive understanding of the impact of distant brain areas on specific interictal and ictal epileptic activities (e.g., isolated spikes, spike trains, seizures). Such knowledge is critically needed, because all kinds of epileptic activities are not equivalent in terms of clinical expression and impact on the progression of the disease. We used surface high-density electroencephalography and multisite intracortical recordings, combined with pharmacological silencing of specific brain regions in the well-known kainate mouse model of temporal lobe epilepsy. We tested the impact of selective regional silencing on the generation of epileptic activities within a continuum ranging from very transient to more sustained and long-lasting discharges reminiscent of seizures. Silencing the contralateral hippocampus completely suppresses sustained ictal activities in the focus, as efficiently as silencing the focus itself, but whereas focus silencing abolishes all focus activities, contralateral silencing fails to control transient spikes. In parallel, we observed that sustained focus epileptiform discharges in the focus are preceded by contralateral firing and more strongly phase-locked to bihippocampal delta/theta oscillations than transient spiking activities, reinforcing the presumed dominant role of the contralateral hippocampus in promoting long-lasting, but not transient, epileptic activities. Altogether, our work provides suggestive evidence that the contralateral hippocampus is necessary for the interictal to ictal state transition and proposes that crosstalk between contralateral neuronal activity and ipsilateral delta/theta oscillation could be a candidate mechanism underlying the progression from short- to long-lasting epileptic activities.

Corrigendum to: Treatment of Bisphosphonate-related Osteonecrosis of Jaw (BRONJ) in Rabbit Model: A Proof-of-concept Animal Study Comparing Angiogenesis Factor Versus Autologous Bone Marrow-derived Osteoblasts (ABMDO)

Corrigendum to: Treatment of Bisphosphonate-related Osteonecrosis of Jaw (BRONJ) in Rabbit Model: A Proof-of-concept Animal Study Comparing Angiogenesis Factor Versus Autologous Bone Marrow-derived Osteoblasts (ABMDO)

Key Anatomical Concepts, Landmarks and Proposed Terminology for Nerve-sparing Gynecologic Surgery: a Narrative Review.

To synthesize the terminology utilized in nerve-sparing surgical literature and propose standardized and non-conflicting terms to allow for consistent vocabulary. We performed a literature search on PubMed using the search terms "pelvis" and "nerve-sparing". Non-gynecologic surgery and animal studies were excluded. A narrative review was performed, focusing on nerves, fasciae, ligaments, and retroperitoneal spaces. Terms from included papers were discussed by all authors, who are surgeons versed in nerve-sparing procedures and one anatomist, and recommendations were made regarding the most appropriate terms based on the frequency of occurrence in the literature and the possibility of overlapping names with other structures. N/A PARTICIPANTS: : N/A INTERVENTIONS: : N/A RESULTS: : 224 articles were identified, with 81 included in the full text review. 48% of articles focused on cervical cancer and 26% on deeply infiltrating endometriosis. Findings were synthesized both narratively and visually. Inconsistencies in pelvic anatomical nomenclature were prevalent across publications. The structure with the most varied terminology was the rectal branch of the inferior hypogastric plexus (IHP) with 14 names. A standardized terminology for pelvic autonomic nerve structures, fasciae, ligaments, and retroperitoneal spaces was proposed to avoid conflicting terms. Surgeons and anatomists should use consistent terminology to facilitate an increased uptake of nerve-sparing techniques in gynecologic surgery through better understanding of surgical technique description. We have proposed a standardized terminology believed to facilitate this goal.

Role of gut microbiota in ischemic stroke: A narrative review of human and animal studies

Role of gut microbiota in ischemic stroke: A narrative review of human and animal studies

Acupoint Sensitivity in Health and Disease: A Systematic Review.

Introduction: The concept of acupoints is a key defining feature of acupuncture, yet the scientific basis of acupoints remains unclear. In recent years, there has been an emerging body of animal studies demonstrating an association between cutaneous sensitivity and visceral pathophysiology, through which acupoints over the skin are sensitized in pathologic conditions. Several studies with humans have also been conducted to assess whether the sensitivity of acupoints is distinct in healthy versus clinical populations. However, no systematic review has been conducted to collate and synthesize the status and quality of human studies on this topic. Methods: A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). Literature search was performed by combining variations of search terms related to acupoints and pain sensitivity in PubMed, EMBASE, and Alt HealthWatch (EBSCOHost). Screening of titles and abstracts and review of full-text articles for eligibility were performed by two independent investigators. Using a predefined template, information on subject characteristics, pathologic conditions, names of assessed acupoints, and relevant main findings were extracted from the included studies. The methodological quality of included studies was assessed using a modified Newcastle-Ottawa Scale (NOS) for case-control studies. A quality assessment checklist was also developed by the present authors to examine the quality of reporting of experimental variables that were considered important for evaluating acupoint sensitivity. Results: A total of 3453 studies were identified from the database search, of which 11 met the eligibility criteria to be included in this review. Six studies examined the mechanical sensitivity of body acupoints, and the remaining five studies examined the mechanical sensitivity of auricular points. Overall, findings suggest that the sensitivity of acupoints may be distinct in healthy versus clinical populations. However, there were various potential sources of bias and substantial heterogeneity across included studies in clinical conditions and acupoints. Conclusion: There is at present insufficient evidence to support or refute that acupoints in humans are sensitized in pathologic conditions. There were various methodological issues, including small sample size and poor reporting of experimental design and variables, which limit the ability to draw a definitive conclusion on this topic. It is also largely unclear whether it is the general body regions rather than specific acupoints that may be sensitized, as most studies did not include nonacupoint location(s) for comparison. Thus, further rigorous research is warranted.

Exploring the Health Benefits of Matcha: A Comprehensive Review

Introduction: Matcha, a finely powdered form of green tea, has recently gained global popularity due to its vibrant green color, distinctive taste, and versatile applications in various food products. Despite its promising nutritional profile, matcha has not received significant attention in the academic community compared to traditional green tea. Purpose of work: The primary objective of this review is to provide a comprehensive overview of the current understanding of matcha's biological properties and its potential health benefits. Methods and materials: A review of the literature available in the PubMed database and Google Scholar, the following keywords were searched: "matcha", “catechin", "EGCG", “cognitive function”, “green tea” State of knowledge: Existing studies have demonstrated that matcha exhibits anticancer properties, enhances cognitive function, improves cardio-metabolic health, and modulates the gut microbiome. Moreover, matcha is known for its anti-inflammatory and antioxidant properties. Summary: This review summarizes the latest research findings on matcha green tea and its potential health benefits. While animal studies have shown promising results, our knowledge of matcha's effects on human health remains limited. Further randomized controlled trials are necessary to fully elucidate its potential health-promoting effects. Therefore, we advocate for continued research into matcha's properties and its integration into dietary practices to promote overall health and well-being.

Combination therapy is it in the future for successfully treating peripheral diabetic neuropathy?

In 2022, the Center for Disease Control and Prevention reported that 11.3% of the United States population, 37.3 million people, had diabetes and 38% of the population had prediabetes. A large American study conducted in 2021 and supported by many other studies, concluded that about 47% of diabetes patients have peripheral neuropathy and that diabetic neuropathy was present in 7.5% of patients at the time of diabetes diagnosis. In subjects deemed to be pre-diabetes and impaired glucose tolerance there was a wide range of prevalence estimates (interquartile range (IQR): 6%-34%), but most studies (72%) reported a prevalence of peripheral neuropathy ≥10%. There is no recognized treatment for diabetic peripheral neuropathy (DPN) other than good blood glucose control. Good glycemic control slows progression of DPN in patients with type 1 diabetes but for patients with type 2 diabetes it is less effective. With obesity and type 2 diabetes at epidemic levels the need of a treatment for DPN could not be more important. In this article I will first present background information on the “primary” mechanisms shown from pre-clinical studies to contribute to DPN and then discuss mono- and combination therapies that have demonstrated efficacy in animal studies and may have success when translated to human subjects. I like to compare the challenge of finding an effective treatment for DPN to the ongoing work being done to treat hypertension. Combination therapy is the recognized approach used to normalize blood pressure often requiring two, three or more drugs in addition to lifestyle modification to achieve the desired outcome. Hypertension, like DPN, is a progressive disease caused by multiple mechanisms. Therefore, it seems likely as well as logical that combination therapy combined with lifestyle adjustments will be required to successfully treat DPN.

Trauma patients with type O blood exhibit unique multi-omics signature with decreased lectin pathway of complement levels.

Patients with type O blood may have an increased risk of hemorrhagic complications due to lower baseline levels of von Willebrand Factor (vWF) and factor VIII, but the transition to a mortality difference in trauma is less clear. We hypothesized that type O trauma patients will have differential proteomic and metabolomic signatures in response to trauma beyond vWF and FVIII alone. Patients meeting the highest level of trauma activation criteria were prospectively enrolled. Blood samples were collected upon arrival to the emergency department. Proteomic and metabolomic (multi-omics) analyses of these samples were performed using liquid chromatography-mass spectrometry. Demographic, clinical, and multi-omics data were compared between patients with type O blood versus all other patients. There were 288 patients with multi-omics data; 146 (51%) had type O blood. Demographics, injury patterns, and initial vital signs and laboratory measurements were not different between groups. Type O patients had increased lengths of stay (7 vs. 6 days, p = 0.041) and a trend towards decreased mortality secondary to traumatic brain injury compared to other causes (TBI, 44.4 % vs. 87.5%, p = 0.055). Type O patients had decreased levels of mannose-binding lectin (MBL) and MBL associated serine proteases 1 and 2 which are required for the initiation of the lectin pathway of complement activation. Type O patients also had metabolite differences signifying energy metabolism and mitochondrial dysfunction. Blood type O patients have a unique multi-omics signature, including decreased levels of proteins required to activate the lectin complement pathway. This may lead to overall decreased levels of complement activation and decreased systemic inflammation in the acute phase possibly leading to a survival advantage, especially in TBI. However, this may later impair healing. Future work will need to confirm these associations, and animal studies are needed to test therapeutic targets. Retrospective Comparative Study, Level IV.

Comparison of δ13C and δ15N of ecologically relevant amino acids among beluga whale tissues

Ecological applications of compound-specific stable isotope analysis (CSIA) of amino acids (AAs) include 1) tracking carbon pathways in food webs using essential AA (AAESS) δ13C values, and 2) estimating consumer trophic position (TP) by comparing relative differences of ‘trophic’ and ‘source’ AA δ15N values. Despite the significance of these applications, few studies have examined AA-specific SI patterns among tissues with different AA compositions and metabolism/turnover rates, which could cause differential drawdown of body AA pools and impart tissue-specific isotopic fractionation. To address this knowledge gap, especially in the absence of controlled diet studies examining this issue in captive marine mammals, we used a paired-sample design to compare δ13C and δ15N values of 11 AAs in commonly sampled tissues (skin, muscle, and dentine) from wild beluga whales (Delphinapterus leucas). δ13C of two AAs, glutamic acid/glutamine (Glx, a non-essential AA) and, notably, threonine (an essential AA), differed between skin and muscle. Furthermore, δ15N of three AAs (alanine, glycine, and proline) differed significantly among the three tissues, with glycine δ15N differences of approximately 10 ‰ among tissues supporting recent findings it is unsuitable as a source AA. Significant δ15N differences in AAs such as proline, a trophic AA used as an alternative to Glx in TP estimation, highlight tissue selection as a potential source of error in ecological applications of CSIA-AA. Amino acids that differed among tissues play key roles in metabolic pathways (e.g., ketogenic and gluconeogenic AAs), pointing to potential physiological applications of CSIA-AA in studies of free-ranging animals. These findings underscore the complexity of isotopic dynamics within tissues and emphasize the need for a nuanced approach when applying CSIA-AA in ecological research.

Noise as an Extrinsic Variable in the Animal Research Facility.

Animal research facilities are noisy environments. The high air change rates required in animal housing spaces tend to create higher noise levels from the heating and cooling systems. Housing rooms are typically constructed of hard wall material that is easily cleaned but simultaneously highly reverberant, meaning that the sound cannot be controlled/attenuated so the sounds that are generated bounce around the room uncontrolled. (Soft, sound-absorbing surfaces generally cannot be used in animal facilities because they collect microbes; various wall surface features and sound control panel options are available, although rarely used.) In addition, many of our husbandry tasks such as cage changing, animal health checks, cleaning, and transporting animals produce high levels of noise. Finally, much of the equipment we have increasingly employed in animal housing spaces, such as ventilated caging motors, biosafety, or procedure cabinets, can generate high levels of background noise, including ultrasound. These and many additional factors conspire to create an acoustic environment that is neither naturalistic nor conducive to a stress-free environment. The acoustic variability both within and between institutions can serve as an enormous confounder for research studies and a threat to our ability to reproduce studies over time and between research laboratories. By gaining a better appreciation for the acoustic variables, paired with transparency in reporting the levels, we might be able to gain a better understanding of their impacts and thereby gain some level of control over such acoustic variables in the animal housing space. The result of this could improve both animal welfare and study reproducibility, helping to address our 3Rs goals of Replacement, Reduction, and Refinement in the animal biomedical research enterprise.

Long Non-coding RNA PCED1B Antisense RNA 1 Promotes Cell Proliferation and Invasion in Hepatocellular Carcinoma by Regulating the MicroRNA-34a/CD44 Axis.

This study aimed to examine the role of long non-coding RNA PCED1B antisense RNA 1 (PCED1B-AS1) in the development of hepatocellular carcinoma (HCC). A total of 62 pairs of HCC tissues and adjacent non-tumor tissues were obtained from 62 HCC patients. The interactions of PCED1B-AS1 and microRNA-34a (miR-34a) were detected by dual luciferase activity assay and RNA pull-down assay. The RNA expression levels of PCED1B-AS1, miR-34a and CD44 were detected by RT-qPCR, and the protein expression level of CD44 was determined by Western blotting. The cell proliferation was detected by cell proliferation assay, and the cell invasion and migration by transwell invasion assay. The HCC tumor growth after PCED1B-AS1 was downregulated was determined by in vivo animal study. PCED1B-AS1 was highly expressed in HCC tissues, which was associated with poor survival of HCC patients. Furthermore, PCED1B-AS1 interacted with miR-34a in HCC cells, but they did not regulate the expression of each other. Additionally, PCED1B-AS1 increased the expression level of CD44, which was targeted by miR-34a. The cell proliferation and invasion assay revealed that miR-34a inhibited the proliferation and invasion of HCC in vitro, while CD44 exhibited the opposite effects. Furthermore, PCED1B-AS1 suppressed the role of miR-34a. Moreover, the knockdown of PCED1B-AS1 repressed the HCC tumor growth in nude mice in vivo. PCED1B-AS1 may play an oncogenic role by regulating the miR-34a/CD44 axis in HCC.

Multi-Cellular Engineered Living Systems to Assess Reproductive Toxicology

Toxicants and some drugs can negatively impact reproductive health. Many toxicants haven’t been tested due to lack of available models. The impact of many drugs taken during pregnancy to address maternal health may adversely affect fetal development with life-long effects and clinical trials do not examine toxicity effects on the maternal-fetal interface, requiring indirect assessment of safety and efficacy. Due to current gaps in reproductive toxicological knowledge and limitations of animal models, multi-cellular engineered living systems may provide solutions for modeling reproductive physiology and pathology for chemical and xenobiotic toxicity studies. Multi-cellular engineered living systems model of functional units of tissues such as microphysiological systems (MPS) and organoids. In this review, we highlight the key functions and structures of human reproductive organs and well-known representative toxicants afflicting these systems. We then discuss current approaches and specific studies where scientists have used MPS or organoids to recreate in vivo markers and cellular responses of the female and male reproductive system, as well as pregnancy-associated placenta formation and embryo development. We provide specific examples of organoids and organ-on-chip that have been used for toxicological purposes with varied success. Finally, we address current issues related to usage of MPS, emerging techniques for improving upon these complications, and improvements needed to make MPS more capable in assessing reproductive toxicology. Overall, multi-cellular engineered living systems have considerable promise to serve as a suitable, alternative reproductive biological model compared to animal studies and 2D culture.

Chitosan–Aloe Vera Composition Loaded with Zinc Oxide Nanoparticles for Wound Healing: In Vitro and In Vivo Evaluations

Global concerns due to the negative impacts of untreatable wounds, as well as the growing population of these patients, emphasize the critical need for advancements in the wound healing materials and techniques. Nanotechnology offers encouraging avenues for improving wound healing process. In this context, nanoparticles (NPs) and certain natural materials, including chitosan (CS) and aloe vera (AV), have demonstrated the potential to promote healing effects. The objective of this investigation is to assess the effect of novel fabricated nanocomposite gel containing CS, AV, and zinc oxide NPs (ZnO NPs) on the wound healing process. The ZnO NPs were synthesized and characterized by X-ray diffraction and electron microscopy. Then, CS/AV gel with different ratios was prepared and loaded with ZnO NPs. The obtained formulations were characterized in vitro based on an antimicrobial study, and the best formulations were used for the animal study to assess their wound healing effects in 21 days. The ZnO NPs were produced with an average 33 nm particle size and exhibited rod shape morphology. Prepared gels were homogenous with good spreadability, and CS/AV/ZnO NPs formulations showed higher antimicrobial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The wound healing findings showed significant wound area reduction in the CS/AV/ZnO NPs group compared to negative control at day 21. Histopathological assessment revealed the advantageous impact of this formulation across various stages of the wound healing process, including collagen deposition (CS/AV/ZnO NPs (2 : 1), 76.6 ± 3.3 compared to negative control, 46.2 ± 3.7) and epitheliogenesis (CS/AV/ZnO NPs (2 : 1), 3 ± 0.9 compared to negative control, 0.8 ± 0.8). CS/AV gel-loaded ZnO NPs showed significant effectiveness in wound healing and would be suggested as a promising formulation in the wound healing process. Further assessments are warranted to ensure the robustness of our findings.

Disease-Associated Q159X Mutant Prion Protein Is Sufficient to Cause Fatal Degenerative Disease in Mice.

PRNP Q160X is one of the five dominantly inheritable nonsense mutations causing familial prion diseases. Till now, it remains unclear how this type of nonsense mutations causes familial prion diseases with unique clinical and pathological characteristics. Human prion protein (PrP) Q160X mutation is equivalent to Q159X in mouse PrP, which produces the mutant fragment PrP1-158. Through intracerebroventricular injection of recombinant adeno-associated virus in newborn mice, we successfully overexpressed mouse PrP1-158-FLAG in the central nervous system. Interestingly, high level PrP1-158-FLAG expression in the brain caused death in these mice with an average survival time of 60 ± 9.1 days. Toxicity correlated with levels of PrP1-158-FLAG but was independent of endogenous PrP. Histopathological analyses showed microgliosis and astrogliosis in mouse brains expressing PrP1-158-FLAG and most of PrP1-158-FLAG staining appeared intracellular. Biochemical characterization revealed that the majority of PrP1-158-FLAG were insoluble and a significant part of PrP1-158-FLAG appeared to contain an un-cleaved signal peptide that may contribute to its cytoplasmic localization. Importantly, an ~10-kDa proteinase K-resistant PrP fragment was detected, which was the same as those observed in patients suffering from this type of prion diseases. To our knowledge, this is the first animal study of familial prion disease caused by Q159X that recapitulates key features of human disease. It will be a valuable tool for investigating the pathogenic mechanisms underlying familial prion diseases caused by nonsense mutations.

Investigation of parenteral nutrition-induced hepatotoxicity using human liver spheroid co-cultures.

Parenteral nutrition (PN) is typically administered to individuals with gastrointestinal dysfunction, a contraindication for enteral feeding, and a need for nutritional therapy. When PN is the only energy source in patients, it is defined as total parenteral nutrition (TPN). TPN is a life-saving approach for different patient populations, both in infants and adults. However, despite numerous benefits, TPN can cause adverse effects, including metabolic disorders and liver injury. TPN-associated liver injury, known as intestinal failure-associated liver disease (IFALD), represents a significant problem affecting up to 90% of individuals receiving TPN. IFALD pathogenesis is complex, depending on the TPN components as well as on the patient's medical conditions. Despite numerous animal studies and clinical observations, the molecular mechanisms driving IFALD remain largely unknown. The present study was set up to elucidate the mechanisms underlying IFALD. For this purpose, human liver spheroid co-cultures were treated with a TPN mixture, followed by RNA sequencing analysis. Subsequently, following exposure to TPN and its single nutritional components, several key events of liver injury, including mitochondrial dysfunction, endoplasmic reticulum stress, oxidative stress, apoptosis, and lipid accumulation (steatosis), were studied using various techniques. It was found that prolonged exposure to TPN substantially changes the transcriptome profile of liver spheroids and affects multiple metabolic and signaling pathways contributing to liver injury. Moreover, TPN and its main components, especially lipid emulsion, induce changes in all key events measured and trigger steatosis.