Administration Of High Doses Research Articles

Nanosuspension-Loaded Dissolving Microneedle Patches for Enhanced Transdermal Delivery of a Highly Lipophilic Cannabidiol.

Transdermal Drug Delivery System (TDDS) offers a promising alternative for delivering poorly soluble drugs, challenged by the stratum corneum's barrier effect, which restricts the pool of drug candidates suitable for TDDS. This study aims to establish a delivery platform specifically for highly lipophilic drugs requiring high doses (log P > 5, dose > 10 mg/kg/d), to improve their intradermal delivery and enhance solubility. Cannabidiol (CBD, log P = 5.91) served as the model drug. A CBD nanosuspension (CBD-NS) was prepared using a bottom-up method. The particle size, polydispersity index (PDI), zeta potential, and concentration of the CBD-NS were characterized. Subsequently, CBD-NS was incorporated into dissolving microneedles (DMNs) through a one-step manufacturing process. The intradermal dissolution abilities, physicochemical properties, mechanical strength, insertion depth, and release behavior of the DMNs were evaluated. Sprague-Dawley (SD) rats were utilized to assess the efficacy of the DMN patch in treating knee synovitis and to analyze its skin permeation kinetics and pharmacokinetic performance. The CBD-NS, stabilized with Tween 80, exhibited a particle size of 166.83 ± 3.33 nm, a PDI of 0.21 ± 0.07, and a concentration of 46.11 ± 0.52 mg/mL. The DMN loaded with CBD-NS demonstrated favorable intradermal dissolution and mechanical properties. It effectively increased the delivery of CBD into the skin, extended the action's duration in vivo, and enhanced bioavailability. CBD-NS DMN exhibited superior therapeutic efficacy and safety in a rat model of knee synovitis, significantly inhibiting TNF-α and IL-1β compared with the methotrexate subcutaneous injection method. NS technology effectively enhances the solubility of the poorly soluble drug CBD, while DMN facilitates penetration, extends the duration of action in vivo, and improves bioavailability. Furthermore, CBD has shown promising therapeutic outcomes in treating knee synovitis. This innovative drug delivery system is expected to offer a more efficient solution for the administration of highly lipophilic drugs akin to CBD, thereby facilitating high-dose administration.

HEPATIC GLYCOGENOSIS ASSOCIATED WITH TYPE 1 DIABETES (A CASE REPORT)

Background:insulin deficiency in diabetes leads to many complications. Hepatocyte glycogen overload, previously known as Mauriac syndrome, is one of them. It is a rare syndrome initially described in type 1 diabetic children in whom significant hyperglycemia is followed by administration of high doses of insulin. Case Presentation:We present the case of a 17-year-old girl withuncontrolled type 1 diabetes. Admitted for growth retardation in addition to impuberism. The clinical examination revealed a weight delay associated with a distended abdomen and hepatomegaly. The laboratory work-up showed cytolysis and anicteric cholestasis with negative viral serologies and immunological assessment. Hepatic ultrasound revealed a 19 cm hepatomegaly without any focal signs or steatosis, as confirmed by a bili-MRI that proved the same finding. A management based on insulin therapy was introduced. The etiological investigation of the hepatic disturbances was negative. Conclusions:The course was satisfactory under appropriate insulin therapy. The diagnosis of hepatic glycogenosis was based on a combination of anamnestic, clinical and histological findings, given the absence of other abnormalities responsible for the liver disturbances.

Dexamethasone promotes renal fibrosis by upregulating ILT4 expression in myeloid-derived suppressor cells.

Studies have shown that adoptive transfer of myeloid-derived suppressor cells (MDSCs) can alleviate various inflammatory diseases, including glomerulonephritis, but the long-term effects of the transferred MDSCs are still unclear. In addition, although glucocorticoids exert immunosuppressive effects on inflammatory diseases by inducing the expansion of MDSCs, the impact of glucocorticoids on the immunosuppressive function of MDSCs and their molecular mechanisms are unclear. In this study, we found that adoptive transfer of MDSCs to doxorubicin-induced focal segmental glomerulosclerosis (FSGS) mice for eight consecutive weeks led to an increase in serum creatinine and proteinuria and aggravation of renal interstitial fibrosis. Similarly, 8 weeks of high-dose dexamethasone administration exacerbated renal interstitial injury and interstitial fibrosis in doxorubicin-induced mice, manifested as an increase in serum creatinine and proteinuria, collagen deposition and α-SMA expression. On this basis, we found that dexamethasone could enhance MDSC expression and secretion of the fibrosis-related cytokines TGF-β and IL-10. Mechanistically, we revealed that dexamethasone promotes the expression of immunoglobulin-like transcription factor 4 (ILT4), which enhances the T-cell inhibitory function of MDSCs and promotes the activation of STAT6, thereby strengthening the expression and secretion of TGF-β and IL-10. Knocking down ILT4 alleviated renal fibrosis caused by adoptive transfer of MDSCs. Therefore, our findings demonstrate that the role and mechanism of dexamethasone mediate the expression and secretion of TGF-β and IL-10 in MDSCs by promoting the expression of ILT4, thereby leading to renal fibrosis.

Cinnamaldehyde: An effective component of Cinnamomum cassia inhibiting Helicobacter pylori

Ethnopharmacological relevanceCinnamomum cassia Presl (Cinnamomum cassia) is a common traditional Chinese medicine, which can promote the secretion and digestion of gastric juice, improve the function of gastrointestinal tract. Cinnamaldehyde (CA) is a synthetic food flavoring in the Chinese Pharmacopoeia. Aim of the studyThis study aimed to search for the active ingredient (CA) of inhibiting H. pylori from Cinnamomum cassia, and elucidate mechanism of action, so as to provide the experimental basis for the treatment of H. pylori infection with Cinnamomum cassia. Materials and methodsIt's in vitro and in vivo pharmacological properties were evaluated based on minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and an acute gastric inflammation model in mice infected with H. pylori. Drug safety was evaluated using the CCK8 method and high-dose administration in mice. The advantageous characteristics of CA in inhibiting H. pylori were confirmed using acidic conditions and in combination with the antibiotics. The mechanism underlying the action of CA on H. pylori was explored using scanning electron microscopy (SEM), adhesion experiments, biofilm inhibition tests, ATP and ROS release experiments, and drug affinity responsive target stability (DARTS) screening of target proteins. The protein function and target genes were verified by molecular docking and Real-Time quantitative reverse transcription PCR (qRT-PCR). ResultsThe results demonstrated that CA was found to be the main active ingredient against H. pylori in Cinnamomum cassia in-vitro tests, with a MIC of 8–16 μg/mL. Moreover, CA effectively inhibited both sensitive and resistant H. pylori strains. The dual therapy of PPI + CA exhibited remarkable in vivo efficacy in the acute gastritis mouse model, superior to the standard triple therapy. DARTS, molecular docking, and qRT-PCR results suggested that the target sites of action were closely associated with GyrA, GyrB, AtpA, and TopA, which made DNA replication and transcription impossible, then leading to inhibition of bacterial adhesion and colonization, suppression of biofilm formation, and inhibition ATP and enhancing ROS. ConclusionsThis study demonstrated the suitability of CA as a promising lead drug against H. pylori, The main mechanisms can target GyrA ect, leading to reduce ATP and produce ROS, which induces the apoptosis of bacterial.

Effects of intermittent overload doses of oral vitamin D3 on serum 25(OH)D concentrations and the incidence rates of fractures, falls, and mortality in elderly individuals: A systematic review and meta-analysis.

Vitamin D is commonly used to prevent and treat osteoporosis, with studies indicating its potential to reduce fractures, falls, and mortality. However, meta-analyses present inconsistent findings regarding its efficacy, particularly reflecting significant variability in data and outcomes related to various dosing regimens. In this meta-analysis, we assessed the impact of high-dose intermittent oral administration of vitamin D3 on serum 25(OH)D levels, fractures, falls, and mortality among elderly individuals. We included 14 randomized controlled trials (RCTs) and employed Review Manager 5.4 for statistical analysis. Our findings indicate that intermittent monthly administration of vitamin D3 (over 800 IU per day) significantly raised serum 25(OH)D levels at all timepoints after six months, maintaining levels above 75 nmol/L throughout the year. This regimen showed no increase in all-cause mortality, with a risk ratio (95% CI) of 0.95 (0.87-1.04). Likewise, it did not significantly reduce the risks of falls and fractures, with risk ratios of 1.02 (0.98-1.05) and 0.95 (0.87-1.04) respectively. Although one-year intermittent administration significantly increased the concentration of 25(OH)D in serum, further research is needed to determine if this method would increase the incidence of falls. Therefore, it is not recommended at this stage due to the lack of demonstrated safety in additional relevant RCTs. This study had been registered at PROSPERO (CRD42022363229).

Relationship Between Symmetrical Peripheral Gangrene Patients and Using Vasopressors in the Intensive Care Unit.

Symmetrical peripheral gangrene (SPG) is a rare yet severe condition characterized by peripheral ischemic lesions without significant vascular occlusion. Its clinical presentation includes peripheral cyanosis, mottling, and symmetrical ischemia of distal limbs, often progressing to gangrene. Recent years have seen a rise in SPG cases, with mortality rates ranging from 40% to 90%. The condition is associated with systemic diseases, such as sepsis, vasculitis, and coagulopathy. DIC frequently complicates SPG, reflecting a disturbed procoagulant-anticoagulant balance and depletion of natural anticoagulants. While vasopressor therapy, particularly high-dose administration, has been implicated in SPG pathogenesis due to sustained vasoconstriction or idiosyncratic responses, recent evidence suggests it may not be the underlying cause. Studies indicate a low incidence of ischemic limb necrosis associated with high-dose vasopressors, with DIC and shock liver potentially explaining limb ischemia instead. The characteristic temporal interval between the onset of shock liver and limb ischemic necrosis suggests a more complex pathophysiology. The role of infectious agents, such as bacteria and viruses, in SPG pathogenesis is under investigation, with both direct vascular invasion and immune-mediated mechanisms proposed. Diagnosis involves ruling out other causes of acral gangrene through clinical examination, laboratory tests, imaging studies, and biopsy. Treatment strategies aim to halt disease progression, eliminate causative factors, and prevent complications. While anticoagulants, vasodilators, and adjunctive therapies like hyperbaric oxygen show promise, the efficacy of interventions varies, emphasizing the need for individualized management. Notably, hemoadsorption has emerged as a promising treatment, demonstrating significant improvement in SPG cases. Amputation remains a lastresort option in irreversible cases. Early recognition and multidisciplinary management are crucial for improving outcomes. Further research is needed to better understand SPG's etiology and develop effective treatments through collaborative efforts.

The predominant Quillaja Saponaria fraction, QS-18, is safe and effective when formulated in a liposomal murine cancer peptide vaccine

Extracts of the Chilean soapbark tree, Quillaja Saponaria (QS) are the source of potent immune-stimulatory saponin compounds. This study compared the adjuvanticity and toxicity of QS-18 and QS-21, assessing the potential to substitute QS-18 in place of QS-21 for vaccine development. QS-18, the most abundant QS saponin fraction, has been largely overlooked due to safety concerns. We found that QS-18 spontaneously inserted into liposomes, thereby neutralizing hemolytic activity, and following administration did not induce local reactogenicity in a footpad swelling test in mice. With high-dose intramuscular administration, transient weight loss was minor, and QS-18 did not induce significantly more weight loss compared to a liposome vaccine adjuvant system lacking it. Two days after administration, no elevation of inflammatory cytokines was detected in murine serum. In a formulation including cobalt-porphyrin-phospholipid (CoPoP) for short peptide sequestration, QS-18 did not impact the formation of peptide nanoparticles. With immunization, QS-18 peptide particles induced higher levels of cancer neoepitope-specific and tumor-associated antigen-specific CD8+ T cells compared to QS-21 particles, without indication of greater toxicity based on mouse body weight. T cell receptor sequencing of antigen-specific CD8+ T cells showed that QS-18 induced significantly more T cell transcripts. In two murine cancer models, vaccination with QS-18 peptide particles induced a similar therapeutic effect as QS-21 particles, without indication of increased toxicity. Antigen-specific CD8+ T cells in the tumor microenvironment were found to express the exhaustion marker PD-1, pointing to the rationale for exploring combination therapy. Taken together, these data demonstrate that QS-18, when formulated in liposomes, can be a safe and effective adjuvant to induce tumor-inhibiting cellular responses in murine models with potential to facilitate or diminish costs of production for vaccine adjuvant systems. Further studies are warranted to assess liposomal QS-18 immunogic, reactogenic and toxicological profiles in mice and other animal species.

Comparative Study on the Effect of Bacopa monniera and Omega3 Fatty Acids on the Cortisol Hormone Level in Cold Stress Induced Wistar Albino Rats

In recent years, researchers have identified several natural compounds that could potentially help to retard mental stress. Extracts of Bacopa monniera (BM), a traditional ayurvedic medicine and omega3 faffy acids (OFA) have been reported to enhance effects mental functions by combating the stress. However, there is still an lacunae studies on which of those two drugs has better results on cortisol hormonal changes due to stress. The current study aimed to compare the effects of BM and omega3 fatty acids on cold stress induced Wistar rats. We divided the animals into seven groups. Group I was control in which rats were kept under ideal laboratory conditions, Group II was given cold water swim stress for a period of one month after which the rats were sacrificed for hormonal assay, Group III in which cold water swim stress given for a month followed by oral administration of normal saline as vehicle for a month, Group IV and V in which cold water swim stress given for a month followed by oral administration of BM extracts 40mg/kg and 80mg/kg respectively as treatment for a month. Group VI and VII includes cold stress followed by oral gavages of OFA 60mg/Kg of Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) for 2 weeks (short-term model) and 4 weeks (long term model) respectively. After the treatment period blood was collected and cortisol assay was done. The data were compared with those of control rats. The results showed an increase in the cortisol level in the stressed group of rats when compared to the treatment group. These results indicate that oral administration of high dose of BM and long-term administration of OFA improves the cortisol level and helps in controlling the stress in rats.

A Hexanuclear Gadolinium(III)-Based Nanoprobe for Magnetic Resonance Imaging of Tumor Apoptosis.

Magnetic resonance imaging (MRI) is instrumental in the noninvasive evaluation of tumor tissues in patients subjected to chemotherapy, thereby yielding essential diagnostic data crucial for the prognosis of tumors and the formulation of therapeutic strategies. Currently, commercially available MRI contrast agents (CAs) predominantly consist of mononuclear gadolinium(III) complexes. Because there is only one Gd(III) atom per molecule, these CAs often require administration in high doses to achieve the desired contrast quality, which inevitably leads to some adverse events. Herein, we develop a six-nuclei, apoptosis-targeting T1 CA, Gd6-ZnDPA nanoprobe, which consists of a hexanuclear gadolinium nanocluster (Gd6) with an apoptosis-targeting group (ZnDPA). The amplification of Gd(III) by the hexanuclear structure generates its high longitudinal relaxivity (44.67 mM-1 s-1, 1T) and low r1/r2 ratio (0.68, 1T). Based on the Solomon-Bloembergen-Morgan (SBM) theory, this notable improvement is primarily ascribed to a long correlation tumbling time (τR). More importantly, the Gd6-ZnDPA nanoprobe shows excellent tumor apoptosis properties with an enhanced MR signal ratio (∼74%) and a long MRI imaging acquisition time window (∼48 h) in 4T1 tumor-bearing mice. This study introduces an experimental gadolinium-based CA for the potential imaging of tumor apoptosis in the context of MRI.

The Impact of Steroid Responder Status on Long-Term Outcomes in Critically Ill Patients With Acute Respiratory Distress Syndrome Receiving High-Dose Glucocorticoids.

Background and objective High-dose intravenous pulsed glucocorticosteroids (GCS) are not part of the standard treatment in acute respiratory distress syndrome (ARDS), and the evidencesupporting their use is conflicting. In clinical practice, however, they are used in specialist settings when clinico-patho-radiological features suggest a potentially steroid-responsive pattern, or as a last resort in cases where patients are unable to be weaned off mechanical ventilation. This study aimed to investigate if an early objective response to high-dose GCS treatment in selected critically ill patients is predictive of survival in ARDS. Methods This study involved a case series of 63 patients treated at a tertiary specialist respiratory ICUbetween 2009 and 2017 who received high-dose GCS for ARDS following a multidisciplinary board agreement. Patients were stratified according to the change in their modified lung injury score (mLIS) between days 0 and 10 following GCS initiation. Changes in mLIS (range: 0-4)were grouped as follows - full responders: ≥2, partial responders: ≥1 and <2, and non-responders: <1. Mortality on discharge and at 6, 12, 18, and 24 months post-ICU discharge was assessed for each group. Data were analysed using logistic regression and a receiver operating curve (ROC) to determine a statistically significant association between the change in mLIS and survival. Results Of the 63 patients, there were seven full responders, 12 partial responders, and 44 non-responders to high-dose GCS. Overall mortality at ICU discharge and 6, 12, 18 and 24 months post-discharge was 29/63 (46.0%), 33/63 (52.4%), 34/63 (54.0%), 34/63 (54.0%), and 35/63 (55.6%) respectively. Mortality was significantly lower in the partial and full-response groups than in the non-response group at all time frames. Logistic regression showed a significant association between the change in mLIS and survival (p<0.001), and a ROC demonstrated that categorising the change in mLIS was a good predictive model for survival (c-statistic 0.86). Conclusions Measuring the change in mLIS by day 10 following high-dose GCS administration for ARDS may beclinically useful in prognosticating such patients. Further research using mLIS as a measure of response to GCS, and larger datasets to enable the evaluation of prognostic factors, may assist clinicians in predicting which patients with persistent ARDS are likely to respond to GCS therapy.

Half a Decade of Intravenous Ketamine Administration: Our Observation Results and Insights regarding its safety

IntroductionKetamine, originally an anesthetic, has emerged as a potent tool in the fight against treatment-resistant depression and suicide. Clinical trials have demonstrated its ability to induce remission of severe depressive symptoms, with effects that can extend over several weeks.Furthermore, research highlights Ketamine’s potential to rapidly reduce suicidal ideation. This suggests Ketamine’s role as an intervention in suicide prevention, especially when conventional treatments prove ineffective. While isolated cases report severe respiratory depression, primarily when combined with other medications, most incidents involve temporary apneic episodes following high-dose intravenous administration. Understanding Ketamine’s safety profile is vital for its clinical optimization and ensuring patient well-being during useObjectivesThis presentation serves to describe, and evaluate our clinic’s safety protocol implemented for intravenous (IV) Ketamine infusions at the General Hospital of Corfu. Our primary goal is to rigorously assess the safety and tolerability of IV Ketamine in a clinical settingMethodsPatients must meet stringent criteria:-Exclude those over 70.-MMSE score above 25.-Controlled blood pressure.-No cardiac insufficiency, myocardial ischemia, or high intraocular/intracranial pressure.-Absence of thyrotoxicosis, psychosis, or seizures.Pre-infusion comprehensive evaluation:-Includes ECG, blood biochemistry studies, and frequent blood pressure checks.-Requires a 2-hour fast.Ketamine infusion:-IV Ketamine administered at 0.5mg/kg in 100ml N/S.-Continuous monitoring of oxygen saturation (PO2) and cardiac rhythm.-Blood pressure checks every 15 minutes.Treatment typically involves 7 sessions over a span of a month, with an initial test dose of 0.25 mg/kg.ResultsKetamine infusions were administered to a total of 208 patients. The majority of participants experienced a slight increase in blood pressure, while there were no significant changes in cardiac rhythm. Additionally, almost all patients reported experiencing dizziness or headaches during the infusion. Notably, nearly half of the patients reported an alteration in taste perception as a side effect. It’s important to highlight that all observed side effects, spontaneously resolved within an hour after the conclusion of the infusion. However, in a small subset of cases (six instances), the side effects were severe enough to necessitate the premature termination of the ketamine infusionConclusions Although ketamine demonstrates a favorable safety profile with minimal major side effects when administered following our established safety protocol. However, we want to underscore the critical importance of vigilant patient monitoring during ketamine administration and the prompt addressing of any adverse effects. This proactive approach is paramount to ensure the safety and overall well-being of patients receiving ketamine treatmentDisclosure of InterestNone Declared

Effects of abrocitinib on pruritus and eczema symptoms and tolerance in patients with moderate‑to‑severe atopic dermatitis in randomized, double‑blind and placebo‑controlled trials: A systematic review and a meta‑analysis.

Abrocitinib is a highly selective Janus kinase 1 (JAK1) inhibitor that can block a multitude of inflammatory signaling pathways that underlie atopic dermatitis (AD). In addition, abrocitinib inhibits JAK1 signaling in sensory neurons to alleviate acute and chronic pruritus during AD. However, substantial variations in efficacy and safety risks remain due to variations in doses applied in clinical use. Therefore for the present study, differences in the efficacy and tolerability of 100 and 200 mg abrocitinib for treating pruritus and eczema symptoms in patients with moderate-to-severe AD were evaluated compared with placebo. Specifically, randomized controlled trials (RCTs) of abrocitinib compared with placebo for the treatment of moderate-to-severe AD were searched on Pubmed, E.B. Stephens Company, China National Knowledge Infrastructure, Wanfang Medical network, Web of Science and related Clinical Trials Registry up to November 2023. In total, two researchers evaluated the quality of the included literature according to the Cochrane Handbook of Systematic Reviews. RevMan 5.3 software was used to conduct a meta-analysis of the efficacy and safety indicators in a cross-comparison of the effects exerted by placebo and 100 and 200 mg abrocitinib. A total of 1,825 patients with moderate-to-severe AD were included across five double-blind, placebo RCTs. Compared with the placebo group, during the double-blind trial period, significant improvements were observed in the investigator's global assessment score, response rate of eczema area and severity index (EASI)-50, EASI-75, EASI-90 and pruritus numerical rating scale (P-NRS) in the 100 and 200 mg abrocitinib groups (P<0.05). However, pairwise control analysis of the 100 and 200 mg group yielded significant differences (P<0.05) in all of the aforementioned therapeutic indicators except for the P-NRS score. In terms of safety, compared with the placebo group, there were significantly higher incidence of nausea, upper respiratory tract viral infection, infections and infestations in the 100 mg abrocitinib group (P<0.05). In addition, there were significantly higher incidence of nausea, gastrointestinal disorder, headache and dizziness in the 200 mg group (P<0.05). There were also significant differences in the incidence of nausea, gastrointestinal disorder and dizziness between the 100 and 200 mg groups (P<0.05). For patients with moderate-to-severe AD, oral administration of 100 or 200 mg abrocitinib once/day was concluded to ameliorate skin pruritus and eczema symptoms to varying degrees, with the efficacy significantly superior at the 200 mg dose. However, the risk of a number of adverse reactions, such as headache, dizziness, nausea and gastrointestinal dysfunction, is also significantly increased. Therefore, patients should be made aware of the risk of adverse drug effects prior to the administration of long-term high abrocitinib doses. Furthermore, large-scale, multi-center, rigorous clinical trials remain necessary to validate the findings from the present study.

Trinitroglycerin-loaded chitosan nanogels: Shedding light on cytotoxicity, antioxidativity, and antibacterial activities

Aim and backgroundTrinitroglycerin (TNG) is a remarkable NO-releasing agent. Here, we synthesized TNG based on chitosan Nanogels (Ngs) for ameliorating complications associated with high-dose TNG administration. MethodTNG-Ngs fabricated through ionic-gelation technique. Fourier-transformed infrared (FT-IR), zeta-potential, dynamic light scattering (DLS), and electron microscopy techniques evaluated the physicochemical properties of TNG-Ngs. MTT was used to assess the biocompatibility of TNG-Ngs, as the antioxidative properties were determined via lactate dehydrogenase (LDH), reactive oxygen species (ROS), and lipid peroxide (LPO) assays. The antibacterial activity was evaluated against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococci (VRE). ResultsPhysicochemical characterization reveals that TNG-Ngs with size diameter (96.2 ± 29 nm), polydispersity index (PDI, 0.732), and negative zeta potential (−1.1 mv) were fabricated. The encapsulation efficacy (EE) and loading capacity (LC) were obtained at 71.1 % and 2.3 %, respectively, with no considerable effect on particle size and morphology. The cytotoxicity assay demonstrated that HepG2 cells exposed to TNG-Ngs showed relative cell viability (RCV) of >80 % for 70 μg/ml compared to the TNG-free drug at the same concentration (P < 0.05). TNG-Ngs showed significant differences with the TNG-free drug for LDH, LPO, and ROS formation at the same concentration (P < 0.001). The antibacterial activity of the TNG-Ngs against S. aureus, E. coli, VRE, and MRSA was higher than the TNG-free drug and Ngs (P < 0.05). ConclusionTNG-Ngs with enhanced antibacterial and antioxidative activity and no obvious cytotoxicity might be afforded as novel nanoformulation for promoting NO-dependent diseases.

Abstract 4059: Vitokine-2: A TIL-targeting tumor activable engineered IL-2 for cancer treatment

Abstract Background: Interleukin-2 is the first approved immune-oncology (IO) drug to treat multiple metastatic cancers with durable and curative antitumor effects. Yet, its application is restricted due to severe toxicity, short half-life, and a small fraction of response rate. To reduce toxicity and improve efficacy, we developed Vitokine-2, a tumor infiltrating lymphocyte (TIL)-targeting, tumor activable, and precision engineered IL-2 that remains inert systemically but activated in the tumor microenvironment (TME). Methods: Through protein and structure-guided precision engineering, the biological activity of IL-2 was optimized, concealed, guided to exhausted TILs, and activated at TME. The biological activity was determined by measuring proliferation (Ki67) of CD8+ T and NK cells using human peripheral blood mononuclear cells (PBMCs). Pharmacokinetics (PK), pharmacodynamics (PD), and anti-tumor efficacy were evaluated in mice, encompassing healthy and multiple syngeneic tumor mouse models. Results: Vitokine-2 was inactive in stimulating CD8+T and NK cell proliferation in vitro. Yet, its biological activity was fully restored following the cleavage and release of the concealing domain. Vitokine-2 displayed a significantly prolonged in vivo pharmacokinetic profile due to half-life extension, concealing and reduction of target sink. Administration of Vitokine-2 in mice resulted in minimal or no detectable activation, proliferation, and expansion of cytotoxic CD8+T and NK cells in the systemic circulation. However, marked CD8+ T cell proliferation and expansion with enhanced expression of granzyme B, a cytotoxic functional biomarker, was observed within the TME. The effect was specific to cytotoxic lymphocytes but not regulatory T cells. Corroborating with the expansion and enhanced functionality of CD8+ T cells in TME, robust antitumor efficacy was observed with Vitokine-2 but not with the non-activable IL-2 counterpart. Furthermore, dose-dependent tumor killing efficacy and complete eradication of tumors were demonstrated in multiple syngeneic tumor models. Vitokine-2 was found to be safe and well tolerated with minimal interferon gamma release and body weight loss even at much higher doses. Conclusion: Vitokine-2 is a TIL-targeting, tumor activable and precision engineered IL-2. It demonstrated robust anti-tumor efficacy with minimal systemic toxicity. It is safe, well tolerated, and permits high dose administration, yielding a widened therapeutic window. Vitokine-2 presents a paradigm-shifting, potentially a first-in-class, highly safe and efficacious IO therapy with an immense potential to address both IO-responsive and unresponsive patient population. Citation Format: Sreerupa V. Challa, Yao-Te Hsieh, Karen Gelinas, Andrea Umana, Wei-chun Weng, Toska Berisha, Cameron Stephens, Yuesheng Li, Jing Xu. Vitokine-2: A TIL-targeting tumor activable engineered IL-2 for cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4059.

Adjusting and validating a procedure for parenteral anaesthesia in neonatal mice.

For neonatal pups, parenteral anaesthesia is said to be not reliable as low doses induce no anaesthesia whereas high doses render high mortality rates. In this work we have adapted parenteral anaesthesia procedures approved for pups >7 days of age, to anaesthetize neonatal animals (postnatal days 3-4; P3-P4) for keeping them immobile for a long period. In our first experiment we analysed the behaviour of P3-P4 mouse pups for 70 min after intraperitoneal administration of low (37.5/3.75 mg/kg) or high (50/5) doses of a ketamine/xylazine anaesthetic mixture, both in the low range as compared with dosages employed in adults. Pups became immobile in ≈7 min and remained immobile for ≈45 min, irrespective of the age and dose of anaesthesia, younger pups (P3) being apparently more sensitive to the dosage. In the second experiment, we studied the response of P3 pups to mildly nociceptive stimulations, performed with a 4.0 g von Frey filament applied to the dorsal aspect of their paws. These stimuli elicited reaction in 100% of the cases in non-anaesthetized pups. The results indicate that the high dose significantly reduced responses as compared with the low dose of anaesthesia. With the low dose, <40% of the pups were unresponsive to nociceptive stimulation, whereas the high dose resulted in 50-60% of the animals not responding. Mortality was low irrespective of age or dose, suggesting that doses can be further increased if needed for invasive experimental procedures.

High-Dose Methotrexate (Hd-Mtx) : Therapeutic Drug Monitoring Of Patients Followed At The Toxicology Department Of The University Hospital Of Setif, Algeria

Therapeutic drug monitoring (TDM) of methotrexate is widely recommended during high-dose administration (&gt; 1 g/m2) in various chemotherapy protocols. This study aims to analyze the blood concentration methotrexate profile to detect delayed elimination in patients monitored at the toxicology department of the University Hospital of Sétif for MTX blood testing. A retrospective descriptive monocentric study was conducted, including all adult patients over 15 years old treated for malignant hematologic disorders with HD-MTX (&gt; 1 g/m2) during their initial therapy. The results revealed that out of 189 monitored patients, only 79 underwent MTX level assessment at 48 hours and 72 hours. Among them, 77.2% exhibited elimination delays at 48 hours and 52% at 72 hours. The analysis of risk factors associated with elimination delay (age, gender, and dosage) did not show any statistically significant correlation. Considering the risk associated with elimination delay in potentiating the toxic effect of MTX, pharmacological therapeutic monitoring remains essential to adjust rescue measures through folinic acid administration and/or intensification of alkaline hydration. This approach aims to enhance the safety and efficacy of HD-MTX-based treatments.

The neuroprotective effect of exogen melatonin upon fetal hippocampus damage caused by high-dose caffeine administration in pregnant rats.

The aim of this study is to evaluate whether exogenous melatonin (MEL) mitigates the deleterious effects of high-dose caffeine (CAF) administration in pregnant rats upon the fetal hippocampus. A total of 32 adult Wistar albino female rats were divided into four groups after conception (n = 8). At 9-20 days of pregnancy, intraperitoneal (i.p.) MEL was administered at a dose of 10mg/kg/day in the MEL group, while i.p. CAF was administered at a dose of 60 mg/kg/day in the CAF group. In the CAF plus MEL group, i.p. CAF and MEL were administered at a dose of 60 and 10mg/kg/day, respectively, at the same period. Following extraction of the brains of the fetuses sacrificed on the 21st day of pregnancy, their hippocampal regions were analyzed by hematoxylin and eosin and Cresyl Echt Violet, anti-GFAP, and antisynaptophysin staining methods. While there was a decrease in fetal and brain weights in the CAF group, it was found that the CAF plus MEL group had a closer weight average to that of the control group. Histologically, it was observed that the pyramidal cell layer consisted of 8-10 layers of cells due to the delay in migration in hippocampal neurons in the CAF group, while the MEL group showed similar characteristics with the control group. It was found that these findings decreased in the CAF plus MEL group. It is concluded that high-dose CAF administration causes a delay in neurogenesis of the fetal hippocampus, and exogenous MEL is able to mitigate its deleterious effects.

Intermittent High-Dose Vitamin D3 Administration in Neonates with Multiple Comorbidities and Vitamin D Insufficiency.

Neonates have an increased risk of vitamin D insufficiency due to the inadequate supplementation of mothers and infants after birth. Insufficiency of vitamin D is frequently detected in critically ill patients and is associated with disease severity and mortality. There is yet to be a consensus on the appropriate regimen of vitamin D3 supplementation in high-risk infants. The main objectives of this study were to determine the prevalence of vitamin D insufficiency in neonates with severe comorbidities and to evaluate whether high-dose vitamin D3 oral administration leads to normal plasmatic concentrations without side effects. The current study was a randomized, prospective trial of 150 patients admitted to the Neonatal Intensive Care Unit (NICU) at Maria Sklodowska Curie Emergency Children's Hospital in Bucharest. Patients were divided into three subgroups based on the chronological order of their admission date. Each subgroup received a different pharmaceutical product of vitamin D3. We administered a dosage of 10,000 IU/kg of vitamin D3 orally in three steps, as follows: at admission, one week after admission, and one month from the first administration, targeting a serum 25-hydroxyvitamin D concentration of at least 40 ng/mL. Most neonates (68%) achieved an optimum vitamin D level after one month, even though only 15% of patients had an optimum concentration at admission. After the first high dose of vitamin D3, there was a 27% increase in the mean vitamin D plasmatic level compared to admission levels. However, after one month, the concentrations decreased in all subgroups due to the gap of three weeks between the last two administrations. An intermittent, weekly high-dose vitamin D3 oral administration leads to a steadier increase and normalization of vitamin D concentration in most critically ill neonates. However, high-dose vitamin D3 administered orally after three weeks decreases vitamin D levels in this high-risk population.

HIGH DOSES OF KETAMINE INFLICT MYOCARDIAL INJURY AND CAUSE CHANGES IN THE RELATIVE BODY WEIGHT TO HEART OF ADULT ALBINO WISTAR RATS

Objective: Ketamine is widely used as an anesthetic agent in surgery and emergency medicine. It is also used for procedural sedation, treatment of depression, pain management, and sometimes as a recreational drug. These uses, however, have recommended doses to prevent myocardial injury. This study, therefore, was designed to investigate the level of injury on the myocardium following the administration of high doses of ketamine and to determine the relative body weight to heart weight of the experimental animals. Method: A total of 12 male albino Wistar rats were used and grouped into four including the control group. They were weighed daily and administered 100 mg, 150 mg, and 200 mg/kg/body weight of ketamine intraperitoneally for 2 weeks and weighed again. Experiment was terminated after 14 days and animals were sacrificed and the heart harvested for analysis. Results: Ketamine caused a significant myocardial injury with increase in the doses in different groups by causing inflammation, hypertrophy, vacuolar degenerative changes, atrophy, and extensive hemorrhage around the myocytes. Weight differentiation was noticed in all experimental groups with heart weight contributing to the total body weight by 1.63%, 1.7%, and 1.2% for the 100 mg, 150 mg, and 200 mg/kg/body weight of ketamine groups, respectively. Conclusion: Higher doses of ketamine cause significant myocardial injury as well as differential changes in body weight and heart weight in experimental animals.

Inhibition of Drp1- Fis1 interaction alleviates aberrant mitochondrial fragmentation and acute kidney injury

BackgroundAcute kidney injury (AKI) is a common clinical disorder with complex etiology and poor prognosis, and currently lacks specific and effective treatment options. Mitochondrial dynamics dysfunction is a prominent feature in AKI, and modulation of mitochondrial morphology may serve as a potential therapeutic approach for AKI.MethodsWe induced ischemia–reperfusion injury (IRI) in mice (bilateral) and Bama pigs (unilateral) by occluding the renal arteries. ATP depletion and recovery (ATP-DR) was performed on proximal renal tubular cells to simulate in vitro IRI. Renal function was evaluated using creatinine and urea nitrogen levels, while renal structural damage was assessed through histopathological staining. The role of Drp1 was investigated using immunoblotting, immunohistochemistry, immunofluorescence, and immunoprecipitation techniques. Mitochondrial morphology was evaluated using confocal microscopy.ResultsRenal IRI induced significant mitochondrial fragmentation, accompanied by Dynamin-related protein 1 (Drp1) translocation to the mitochondria and Drp1 phosphorylation at Ser616 in the early stages (30 min after reperfusion), when there was no apparent structural damage to the kidney. The use of the Drp1 inhibitor P110 significantly improved kidney function and structural damage. P110 reduced Drp1 mitochondrial translocation, disrupted the interaction between Drp1 and Fis1, without affecting the binding of Drp1 to other mitochondrial receptors such as MFF and Mid51. High-dose administration had no apparent toxic side effects. Furthermore, ATP-DR induced mitochondrial fission in renal tubular cells, accompanied by a decrease in mitochondrial membrane potential and an increase in the translocation of the pro-apoptotic protein Bax. This process facilitated the release of dsDNA, triggering the activation of the cGAS-STING pathway and promoting inflammation. P110 attenuated mitochondrial fission, suppressed Bax mitochondrial translocation, prevented dsDNA release, and reduced the activation of the cGAS-STING pathway. Furthermore, these protective effects of P110 were also observed renal IRI model in the Bama pig and folic acid-induced nephropathy in mice.ConclusionsDysfunction of mitochondrial dynamics mediated by Drp1 contributes to renal IRI. The specific inhibitor of Drp1, P110, demonstrated protective effects in both in vivo and in vitro models of AKI.