Large Doses Research Articles

Interpreting the biological effects of protons as a function of physical quantity: linear energy transfer or microdosimetric lineal energy spectrum?

The choice of appropriate physical quantities to characterize the biological effects of ionizing radiation has evolved over time coupled with advances in scientific understanding. The basic hypothesis in radiation dosimetry is that the energy deposited by ionizing radiation initiates all the consequences of exposure in a biological sample (e.g., DNA damage, reproductive cell death). Physical quantities defined to characterize energy deposition have included dose, a measure of the mean energy imparted per unit mass of the target, and linear energy transfer (LET), a measure of the mean energy deposition per unit distance that charged particles traverse in a medium. The primary advantage of using the “dose and LET” physical system is its relative simplicity, especially for presenting and recording results. Inclusion of additional information such as the energy spectrum of charged particles renders this approach adequate to describe the biological effects of large dose levels from homogeneous sources. The primary disadvantage of this system is that it does not provide a unique description of the stochastic nature of radiation interactions. We and others have used dose-averaged LET (LETd) as a correlative physical quantity to the relative biological effectiveness (RBE) of proton beams. This approach is based on established experimental findings that proton RBE increases with LETd. However, this approach might not be applicable to intensity-modulated proton therapy or other applications in which the proton energy spectrum is highly heterogeneous. In the current study, we irradiated cancer cells with scanning proton beams with identical LETd (3.4 keV/µm) but arising from two different proton energy/LET spectra (a narrow spectrum in group 1 and a widespread heterogeneous spectrum in group 2). Clonogenic survival after irradiation revealed significant differences in RBE at any cell surviving fraction: e.g., at a surviving fraction of 0.1, the RBE was 0.97 ± 0.03 in group 1 and 1.16 ± 0.04 in group 2 (p≤0.01), validating our hypothesis that LETd alone may not adequately indicate proton RBE. Further analysis showed that microdosimetric spectrum (the probability density function of the stochastic physical quantity lineal energy y) was helpful for interpreting observed differences in biological effects. However, more accurate use of microdosimetric spectrum to quantify RBE requires a cell line–specific mechanistic model.

Decreasing IV magnesium infusion time to improve delivery of patient care.

Hypomagnesemia is a common issue in patients with cancer due to magnesium wasting drugs like calcineurin inhibitors, chemotherapy sides effects such as diarrhea, and poor oral intake. Historically, magnesium has been given over prolonged infusions due to concern for rapid elimination of magnesium when large doses are administered. At UW Health, magnesium was given at a rate of 1g/60 min. A prolonged infusion rate often creates logistical issues including limited IV access, incompatibility concerns and increased chair time. The purpose of this project is to increase the infusion rate of IV magnesium without compromising therapeutic repletion, benefit, and safety. The magnesium infusion rate was increased to the following rates: 4g/60 min, 2g/30 min, 1g/15 min. The primary outcome is the grams of IV magnesium replaced per outpatient visit between the pre-intervention (prolonged) and post-intervention (rapid) groups. Secondary outcomes include assessment of differences in chair time between groups and total incidence of critical magnesium lab values. There was no statistically significant difference in magnesium requirements per outpatient visit between a prolonged and rapid magnesium infusion rate (2.18g vs 2.15g; p = 0.49). Additionally, there was no difference in number of outpatient visits (3 vs 3; p = 1). The average chair time was decreased by 110 min per outpatient encounter between the prolonged and rapid magnesium infusion rate, which was determined to be clinically and statistically significant. This study suggests that there is no difference in magnesium requirements between a rapid or prolonged magnesium infusion in both solid and liquid tumor patients.

Cannabis and Cannabinoid Signaling: Research Gaps and Opportunities.

Cannabis and its products have been used for centuries for both medicinal and recreational purposes. The recent widespread legalization of cannabis has vastly expanded its use in the United States across all demographics except for adolescents. Meanwhile, decades of research have advanced our knowledge of cannabis pharmacology and particularly of the endocannabinoid system with which the components of cannabis interact. This research has revealed multiple targets and approaches for manipulating the system for therapeutic use and to ameliorate cannabis toxicity or cannabis use disorder. Research has also led to new questions that underscore the potential risks of its widespread use, particularly the enduring consequences of exposure during critical windows of brain development or for consumption of large daily doses of cannabis with high content Δ 9-tetrahydrocannabinol. This article highlights current neuroscience research on cannabis that has shed light on therapeutic opportunities and potential adverse consequences of misuse and points to gaps in knowledge that can guide future research. SIGNIFICANCE STATEMENT: Cannabis use has escalated with its increased availability. Here, the authors highlight the challenges of cannabis research and the gaps in our knowledge of cannabis pharmacology and of the endocannabinoid system that it targets. Future research that addresses these gaps is needed so that the endocannabinoid system can be leveraged for safe and effective use.

Assessment of the Impact of Dietary Supplementation with Epigallocatechin Gallate (EGCG) on Antioxidant Status, Immune Response, and Intestinal Microbiota in Post-Weaning Rabbits.

This study was conducted to investigate the impact of EGCG on antioxidant stress, immune response, and intestinal microbiota flora in post-weaning rabbits. A total of 144 40 d Ira rabbits (equally divided by sex), were randomly allocated to six treatments. with five groups receiving doses of 200, 400, 600, 800, and 1000 mg/kg of EGCG, while one group served as a control without EGCG. Over 48 days, this study the assessed growth performance, antioxidant capacity, immune system, intestinal morphology, and cecal microbiota in the rabbits. The results showed that EGCG did not affect growth performance; however, significant linear and quadratic correlations were observed between the MDA, T-AOC, and GSH-Px activities in the liver and jejunum (p < 0.05). Quadratic effects were observed for the spleen and thymus indexes and serum IgG levels with increasing EGCG dosages (p < 0.05). Additionally, positive linear and quadratic effects were found on the ileal villus height and the villus height/crypt depth ratio. The relative abundances of Euryarchaeota, Patescibacteria, and Synergistota were significantly enriched in rabbits fed with high dosages (600-1000 mg/kg) of EGCG. Conclusively, the addition of large doses of EGCG (400-800 mg/kg) can effectively suppress oxidative stress and alleviate weaning stress, thereby contributing to the protection of post-weaning rabbits.

Jianpi-Huatan-Huoxue-Anshen formula ameliorates gastrointestinal inflammation and microecological imbalance in chemotherapy-treated mice transplanted with H22 hepatocellular carcinoma

BACKGROUND Jianpi-Huatan-Huoxue-Anshen formula [Tzu-Chi cancer-antagonizing &amp; life-protecting II decoction (TCCL)] is a Chinese medical formula that has been clinically shown to reduce the gastrointestinal side effects of chemotherapy in cancer patients and improve their quality of life. However, its effect and mechanism on the intestinal microecology after chemotherapy are not yet clear. AIM To discover the potential mechanisms of TCCL on gastrointestinal inflammation and microecological imbalance in chemotherapy-treated mice transplanted with hepatocellular carcinoma (HCC). METHODS Ninety-six mice were inoculated subcutaneously with HCC cells. One week later, the mice received a large dose of 5-fluorouracil by intraperitoneal injection to establish a HCC chemotherapy model. Thirty-six mice were randomly selected before administration, and feces, ileal tissue, and ileal contents were collected from each mouse. The remaining mice were randomized into normal saline, continuous chemotherapy, Yangzheng Xiaoji capsules-treated, and three TCCL-treated groups. After treatment, feces, tumors, liver, spleen, thymus, stomach, jejunum, ileum, and colon tissues, and ileal contents were collected. Morphological changes, serum levels of IL-1β, IL-6, IL-8, IL-10, IL-22, TNF-α, and TGF-β, intestinal SIgA, and protein and mRNA expression of ZO-1, NF-κB, Occludin, MUC-2, Claudin-1, and IκB-α in colon tissues were documented. The effect of TCCL on the abundance and diversity of intestinal flora was analyzed using 16S rDNA sequencing. RESULTS TCCL treatment improved thymus and spleen weight, thymus and spleen indexes, and body weight, decreased tumor volumes and tumor tissue cell density, and alleviated injury to gastric, ileal, and colonic mucosal tissues. Among proteins and genes associated with inflammation, IL-10, TGF-β, SIgA, ZO-1, MUC-2, and Occludin were upregulated, whereas NF-κB, IL-1β, IL-6, TNF-α, IL-22, IL-8, and IκB-α were downregulated. Additionally, TCCL increased the proportions of fecal Actinobacteria , AF12 , Adlercreutzia , Clostridium , Coriobacteriaceae , and Paraprevotella in the intermediate stage of treatment, decreased the proportions of Mucipirillum , Odoribacter , RF32 , YS2 , and Rikenellaceae but increased the proportions of p_Deferribacteres and Lactobacillus at the end of treatment. Studies on ileal mucosal microbiota showed similar findings. Moreover, TCCL improved community richness, evenness, and the diversity of fecal and ileal mucosal flora. CONCLUSION TCCL relieves pathological changes in tumor tissue and chemotherapy-induced gastrointestinal injury, potentially by reducing the release of pro-inflammatory factors to repair the gastrointestinal mucosa, enhancing intestinal barrier function, and maintaining gastrointestinal microecological balance. Hence, TCCL is a very effective adjuvant to chemotherapy.

Evaluation of the chronic oral toxicity of the classical ancient prescription Kai-Xin-San

Ethnopharmacological relevanceThe Kai-Xin-San (KXS), as an ancient classic prescription, has been used for the treatment of amnesia for thousands of years. Modern clinical and non-clinical pharmacological studies have found that it has significant therapeutic effects on dementia and depression, but there are relatively few studies on its safety. Aim of the studySubacute and chronic toxicity studies were conducted to investigate the symptoms, severity, target organs, development and recovery of toxic reactions, as well as the toxic dose. These studies provide technical data for ensuring the safety of KXS. Materials and methodsIn the sub-acute toxicity study, rats were orally administered KXS at doses of 0.80, 1.61, 3.22, and 6.43 g/kg body weight for a duration of 4 weeks. In the chronic toxicity study, rats were orally administered KXS at doses of 0.27, 0.81, and 2.43 g/kg body weight for a duration of 26 weeks, and a withdrawal study was conducted for a period of 4 weeks after the treatment.The rats were observed daily for clinical signs and mortality. Changes in body weight, food consumption, and water consumption were periodically monitored. Additionally, urinalysis results, hematological and biochemical parameters, relative organ weights, and pathology were monitored at specific observation time points. ResultsIn the sub-acute toxicity study, necropsy of dead and moribund rats revealed evident distension and swelling of the gastrointestinal tract, as well as thinning of the intestinal wall. The main adverse reactions observed included flatulence, piloerection, abnormal breathing sounds, and emaciation. Doses of 1.61 g/kg and below did not cause animal death. The gastrointestinal system is the main target organ of toxicity. In the chronic toxicity study, the no-observed-adverse-effect-level (NOAEL) of KXS was 0.27 g/kg, and its toxic effects were primarily concentrated in the gastrointestinal system. This led to secondary pathological changes in the immune system, hematopoietic system, and heart, suggesting that relevant indicators should be monitored when large doses are used clinically for an extended period of time. ConclusionsDuring the rodent toxicity evaluation, severe gastrointestinal damage was observed when KXS, powdered with crude drugs, was administered. The NOAEL for rats was found to be 0.27 g/kg/day.

6408 Familial Hypoparathyroidism With Elevated Parathyroid Hormone Due To A PTH Mutation Responsive To Teriparatide

Abstract Disclosure: N. Mukhtar: None. B. Alghamdi: None. M. Alswailem: None. A.S. Alzahrani: None. Introduction: Apart from vitamin D disorders, causes of congenital hypocalcemia (HypoCa) include genetic defects causing familial hypoparathyroidism (FH), and defects in PTH receptor or its signalling pathway (PTH resistance). The former is typically characterized by low plasma PTH and the latter by elevated PTH levels. In this report, we describe a family with FH but with significant elevation of functionally inactive PTH due to a PTH mutation. We also show a positive therapeutic impact of recombinant human PTH (teriparatide) therapy on HypoCa in one of these siblings who was not well controlled on calcitriol and calcium replacement. Case description: The proband is a 34-year-old lady who has history of chronic HypoCa since birth with several admissions for severe HypoCa and recurrent seizures during childhood. She and her three brothers (a 32-year-old male twin and an 18-year-old male) were diagnosed to have Pseudohypoparathyroidism type 1b based on the presence of chronic HypoCa (serum Ca 1.6-1.85 mmol/l) since birth associated with significantly elevated plasma PTH levels in the range of 310-564 pg/dl (normal range 10-65) and absence of signs of Albright hereditary osteodystrophy. Laboratory workup of the proband recently showed: PTH 514 ng/L (NR 15-65) , calcium 1.81 mmol/l (NR 2.1-2.6), phosphate 1.67mmol/L (NR 0.8-1.4), magnesium 0.73 mmol/L (NR 0.7-1.0), albumin 38 g/L (NR 40-50), Alkaline phosphatase 56 U/L, eGFR &amp;gt;60 ml/min/1.73 m2, creatinine 78 umol/L and 25-hydroxyvitamin D 77 nmol/l (NR 50-120). Daily excretion of calcium was normal at 3.38 mmol and an ultrasound of the kidneys suggest nephrocalcinosis. Skeletal X-rays and bone mass densitometry were normal. Molecular studies: WES showed no potentially pathogenic variants in GNAS, PTHR, CASR, VDR, and CYP27B1 but a previously reported homozygous variant in the PTH, exon 3 (NM_000315.4: c.128G&amp;gt;A, p.Gly43Glu). This was confirmed by Sanger sequencing in the patient and two of her brothers. This variant was assessed to be likely pathogenic or likely damaging by several in silico analysis tools including Polyphen2, MutPred, PROVEAN, DEOGEN2 and VUS by ACMG, SIFT, Mutation Assessor and FATHMM. Management: Because the patient’s HypoCa was not controlled on large doses of calcitriol and calcium carbonate, a trial of teriparatide 20 mcg SC daily resulted in normalization of calcium and PTH levels. The patient reported significant improvement in her general wellbeing with loss of numbness, tingling, muscle spasms and tetany of the fingers. She has been on teriparatide for the last year with excellent improvement in her quality-of-life Conclusion: High PTH in the presence of congenital hypoCa is not always due to receptor or post-receptor defect and can be due to a mutated biologically inactive PTH. In such cases, treatment with Teriparatide may result in stabilization of biochemical profile and improve quality of life. Presentation: 6/2/2024

7370 Review of the Literature, and Report of a Series of Patients with Lactose Intolerance and Levothyroxine Malabsorption in Treatment with Liquid L-T4

Abstract Disclosure: S. Ferrari: None. A. Patrizio: None. V. Mazzi: None. F. Ragusa: None. C. Botrini: None. G. Elia: None. E. Balestri: None. E. Barozzi: None. L. Rugani: None. F. Bracchitta: None. G. Stoppini: None. G. Frenzilli: None. E. Baldini: None. C. Virili: None. S. Benvenga: None. P. Fallahi: None. A. Antonelli: None. Intolerance to lactose-containing foods is frequent, with a prevalence of 7-20% in Caucasians, and of 80-95% among Native Americans. Therefore, lactose intolerance (LI) issue needs to be taken in account in the management of hypothyroid patients needing large doses of levothyroxine (L-T4) (&amp;gt; 1.7-2 μg/kg/day) to achieve euthyroidism. Indeed, the absorption of oral T4 may be affected in patients with LI, by following a diet containing lactose, whereas it is resulted to be improved with a lactose-free diet. Lactose is often present as a supplementary ingredient in many commercially available drugs, as L-T4 preparations. In susceptible individuals, drugs containing lactose can cause LI symptoms, and lactose in L-T4 preparations could impair thyroxine absorption. Moreover, it has been shown that patients with LI requiring an increased dosage of L-T4 benefit from a treatment with a lactose-free L-T4 formulation. The lactose-free liquid L-T4 formulation is able to circumvent LI malabsorption leading to the normalization of thyroid-stimulating hormone (TSH) in patients with subclinical hypothyroidism, and long term stable TSH levels. Further studies will be needed to evaluate the liquid L-T4 formulation in larger numbers of patients with hypothyroidism and LI. Presentation: 6/3/2024

8539 Curcumin a Double Edged Sword: A Case of Curcumin Induced Pituitary Macroadenoma Apoplexy

Abstract Disclosure: P. Balozian: None. D. Alfakara: None. M. Linz: None. &amp;lt;Curcumin, the active component of turmeric, exerts numerous beneficial anti-inflammatory, antiplatelet, and anticoagulant effects. Recent literature has shown however that curcumin inhibits proliferation and induces apoptosis of pituitary cells. Despite these findings, there are limited clinical cases reporting an association between curcumin and pituitary adenoma apoplexy.We report the case of a 39-year old G9P6A3 female with Hashimoto’s disease and class II obesity who presented with a constant bifrontal excruciating headache, blurry vision, photophobia, and nausea. She also had fatigue and amenorrhea for two years. Her exam showed normal vitals, decreased visual acuity, diplopia, and bitemporal hemianopsia. Data showed a serum prolactin of 69 ug/L , plasma IGF-1 of 133 ng/ml (Z score -0.4), TSH of 2.58 with a free T4 of 0.47 ng/dl [0.61-1.12 ng/dL], a random cortisol of 12.7 mcg/dl despite her stress and pain, ACTH of 27 pg/ml, DHEA-S of 46 mcg/dl, an LH of 0.5 IU/L, and an FSH of 4mIU/ml with an estradiol of 25 pg/ml. MRI of the pituitary revealed a 1.8 cm macroadenoma with a mass effect on the overlying optic chiasm and a T1 intrinsic hyperintense signal indicative of a hemorrhagic component. She was given IV dexamethasone for 24 hours then underwent transsphenoidal resection of the hemorrhagic tumor that resulted in rapid resolution of headaches and visual symptoms. She was not given any glucocorticoids during or after surgery. Labs immediately after surgery revealed a prolactin of &amp;lt;1ug/L and a cortisol of 26.7 mcg/dl. Pathology showed corticotroph tumor with hemosiderin deposition with a 4.2% Ki67 and negative ACTH immunostaining. On medication review, patient had been taking large doses of curcumin. In the absence of other recent precipitating factors, it was highly likely that she had curcumin-triggered apoplexy of a pituitary macroadenoma. Most recent bloodwork, about 20 months from presentation, revealed a serum prolactin of 5.0 ug/L, IGF-1 of 123ng/mL (Z score -0.6), TSH of 0.97 mIU/L with a free T4 of 0.85 ng/dL, a random cortisol of 5.3 ug/dL, ACTH of 18.2 pg/mL, DHEA-S of 94 ug/dL, LH of 2.5 IU/L, FSH of 4.3 IU/L, and an estradiol of 45 pg/mL. Regular menstrual cycles had resumed. Headaches, nausea, and vision abnormalities completely resolved.The case illustrates the need to identify any herbal remedies and supplements a patient is taking, particularly turmeric, as supplements may contribute to increased bleeding tendency of an already existing adenoma. The case also emphasizes the potential rapid recovery of pituitary function after surgical resection of an apoplectic pituitary tumor.&amp;gt; Presentation: 6/3/2024

7915 A Case of Severe Hypothyroidism in a Patient with Nephrotic Syndrome presenting with Rhabdomyolysis requiring Levothyroxine and Liothyronine combination therapy

Abstract Disclosure: S.S. Mohammed: None. E.T. Ngo: None. S. Tadisina: None. B.M. Drees: None. Background: Nephrotic syndrome is known to worsen hypothyroidism via urinary loss of thyroid binding globulin, transthyretin, albumin and other proteins, often requiring escalating levothyroxine doses. Severe uncontrolled hypothyroidism can result in rhabdomyolysis, although this presentation is quite rare. Clinical case: We present a case of a 50-year-old male with long-standing Hashimoto’s hypothyroidism, biopsy-proven minimal change disease with nephrotic syndrome, dyslipidemia, and hypertension, who was admitted for generalized myalgia, weakness, and progressive swelling of bilateral hands and feet for one month. He had been off levothyroxine 3 months prior to presentation. He previously required large doses of oral levothyroxine, as high as 350mcg daily, but never achieved a euthyroid state despite reported adherence to therapy with the high levothyroxine doses.Laboratory workup showed severe hypothyroidism (free thyroxine &amp;lt;0.25ng/dL [0.6-1.6ng/dL] with markedly elevated thyroid stimulating hormone 282.03 mIU/mL [0.3-5.6mIU/mL]), along with acute kidney injury and rhabdomyolysis (Creatine kinase 4882 U/L[38-234U/L]). He was hemodynamically stable with intact mentation and was not deemed to be in myxedema coma. Physical examination was consistent with hypothyroidism with periorbital swelling, dry skin, deep hoarse voice, bilateral hand and feet edema, and delayed deep tendon reflexes. Thyroid function tests and clinical symptoms failed to improve after 8 days, despite high doses of levothyroxine IV (200mcg). Creatine kinase remained high at 4994 U/L [38-234U/L] despite adequate fluid hydration. Liothyronine 5mcg orally was started in addition to levothyroxine 200mcg IV. Repeat thyroid function tests after 2 days of combined IV levothyroxine and oral liothyronine therapy showed significant downtrend in TSH to 154.12 uIU/ml [0.3-5.6mIU/mL] and increase in free thyroxine to 0.44ng/dl [0.6-1.6ng/dL]. Creatine kinase also down trended to 3181U/L[38-234U/L] on D4 of IV levothyroxine 200mcg IV with liothyronine 5mcg daily. He was discharged stable and clinically improved on oral levothyroxine and liothyronine. Laboratory evaluation 10 days later showed further improvement in TFTs (TSH 66.0[0.3-5.6mIU/mL]), free thyroxine 0.6 [0.6-1.6ng/dL] Conclusion: This case presents a unique and unusual clinical course in symptomatic primary hypothyroidism with rhabdomyolysis and AKI. Rhabdomyolysis due to hypothyroidism, without an obvious precipitating factor, has been previously reported, but is very rare. There is limited evidence regarding combination treatment with levothyroxine and liothyronine in primary hypothyroidism; however, as demonstrated in this patient, combination therapy resulted in clinical and biochemical improvement of thyroid function. Presentation: 6/2/2024

Sustainable chemometric analysis of tension headache drugs in the presence of nephrotoxic impurities

A three-drug combination of caffeine, aspirin and paracetamol is widely prescribed as a first-line treatment for tension headaches and migraine attacks. Being of easy access as an over-the-counter medication, renal papillary necrosis may be caused if large doses are taken chronically. Moreover, several toxic impurities such as p-aminophenol and p-hydroxy acetophenone may be formed during the synthesis or storage of paracetamol. These impurities are classified as nephrotoxic and teratogenic materials which obliges pharmaceutical companies to develop cost-effective methodologies for their detection along with paracetamol itself. During the current study, multivariate chemometric-assisted spectrophotometric models namely; Partial Least Squares, Genetic Algorithm-Partial Least Squares and Multivariate Curve Resolution-Alternating Least Squares were developed for assaying and resolving the complex spectral overlap of the ternary combination in the presence of the nephrotoxic impurities; p-aminophenol and p-hydroxy acetophenone. A comparison was held between the three models where the optimized Genetic Algorithm-Partial Least Squares and Multivariate Curve Resolution-Alternating Least Squares models reduced the root mean square by 18.1%, 21.7%, 20.0%, 43.9% and 11.5% and 31.5%, 32.6%, 39.3%, 54.6% and 37.9% for caffeine, aspirin, paracetamol, p-aminophenol and p-hydroxy acetophenone, respectively. Panadol® migraine tablets were successfully analyzed using the constructed models without interference from the excipients. A statistical comparative analysis and greenness evaluation were carried out using two assessment tools including the “Green Analytical Procedure Index” and the “Analytical Greenness metric”. Also, the “Whiteness Analytical Chemistry tool” using the RGB12 model and the Blueness Applicability Grade Index were applied. Greener quadrants and a high score of 0.74 for the greenness tools were achieved with accepted statistical parameters regarding t and f values. Also, the high scores of the Blueness Applicability Grade Index and RGB12 metrics of 90 and 98.3, respectively confirmed the method's wide practicality and utility. Although other chemometric methods were reported for assaying the ternary combination, our developed method was the only one that incorporated toxic impurities during the analysis along with implementing greenness, whiteness and blueness assessments to ensure the method's sustainability.

Physiology-based pharmacokinetic model with relative transcriptomics to evaluate tissue distribution and receptor occupancy of anifrolumab.

Type I interferons contribute to the pathogenesis of several autoimmune disorders, including systemic lupus erythematosus (SLE), systemic sclerosis, cutaneous lupus erythematosus, and myositis. Anifrolumab is a monoclonal antibody that binds to subunit 1 of the type I interferon receptor (IFNAR1). Results of phase IIb and phase III trials led to the approval of intravenous anifrolumab 300 mg every 4 weeks (Q4W) alongside standard therapy in patients with moderate-to-severe SLE. Here, we built a population physiology-based pharmacokinetic (PBPK) model of anifrolumab by utilizing the physiochemical properties of anifrolumab, binding kinetics to the Fc gamma neonatal receptor, and target-mediated drug disposition properties. A novel relative transcriptomics approach was employed to determine IFNAR1 expression in tissues (blood, skin, gastrointestinal tract, lungs, and muscle) using mRNA abundances from bioinformatic databases. The IFNAR1 expression and PBPK model were validated by testing their ability to predict clinical pharmacokinetics over a large dose range from different clinical scenarios after subcutaneous and intravenous anifrolumab dosing. The validated PBPK model predicted high unbound local concentrations of anifrolumab in blood, skin, gastrointestinal tract, lungs, and muscle, which exceeded its IFNAR1 dissociation equilibrium constant values. The model also predicted high IFNAR1 occupancy with subcutaneous and intravenous anifrolumab dosing. The model predicted more sustained IFNAR1 occupancy ≥90% with subcutaneous anifrolumab 120 mg once-weekly dosing vs. intravenous 300 mg Q4W dosing. The results informed the dosing of phase III studies of anifrolumab in new indications and present a novel approach to PBPK modeling coupled with relative transcriptomics in simulating pharmacokinetics of therapeutic monoclonal antibodies.

PULSAR Effect: Revealing potential synergies in combined radiation therapy and immunotherapy via differential equations

PULSAR (personalized ultrafractionated stereotactic adaptive radiotherapy) is a form of radiotherapy method where a patient is given a large dose or “pulse” of radiation a couple of weeks apart rather than daily small doses. The tumor response is then monitored to determine when the subsequent pulse should be given. Pre-clinical trials have shown better tumor response in mice that received immunotherapy along with pulses spaced 10 days apart. However, this was not the case when the pulses were 1 or 4 days apart. Therefore, a synergistic effect between immunotherapy and PULSAR is observed when the pulses are spaced out by a certain number of days. In our study, we aimed to develop a mathematical model that can capture the synergistic effect by considering a time-dependent weight function that takes into account the spacing between pulses. We determined feasible parameters by fitting murine tumor volume data of six treatment groups via simulated annealing algorithm. Applying these parameters to the model we simulated 4000 trials with varying sequencing of pulses. These simulations indicated that if pulses were spaced apart by at least 9 days the tumor volume was about 200 mm3 to 250 mm3 smaller when treated with PULSAR combined with immunotherapy. We successfully demonstrate that our model is simple to implement and can generate tumor volume data that is consistent with the pre-clinical trial data. Our model has the potential to aid in the development of clinical trials of PULSAR therapy.

An efficient polyaluminum lanthanum silicate coagulant for phosphorus removal and algal bloom control

Due to the advantages of convenient operation and low cost, the use of coagulants is considered a promising method for algae bloom harvesting. However, large dosages, poor algal bloom control rates, and limited phosphorus removal efficiency restrict the usage of most coagulants. In this study, a novel polyaluminum lanthanum silicate (PALS) coagulant was used to remove phosphorus and control algal bloom. The results of isotherm study showed that phosphorus adsorption on PALS fitted Freundlich model, indicating chemisorption and heterogeneous multilayer adsorption were the mechanisms of phosphorus adsorption by PALS. The maximum phosphorus adsorption capacity of PALS by Langmuir model was 485.30mg/g. According to the algal bloom control experiments, the removal of algae and phosphorus was slight at low dosages of PALS (2mg/L and 5mg/L). Short-term control of the algal bloom was observed within 2 days in PALS-10 group, but the bloom recovered afterward, while phosphorus and algae were almost completely removed in PALS-15 and PALS-20. When the dosage of PALS was ≤ 10mg/L, PALS coated the algal cell surfaces and induced mild oxidative stress, showing a little damage to cell integrity. However, the PALS dose over 15mg/L could effectively capture algal cells through charge neutralization, cause severe oxidative stress, strongly upregulate the expression of selected five genes, significantly damage cell integrity, and lead to algae lysis. These findings demonstrated that PALS is a promising coagulant for phosphorus removal and algal bloom control in eutrophic waters, and the minimum threshold of its usage was 15mg/L.

N-acetylcysteine is effective in ameliorating nephrotoxicity induced by low dose but not large dose of 5-Fluorouracil in rats.

N-acetylcysteine is effective in ameliorating nephrotoxicity induced by low dose but not large dose of 5-Fluorouracil in rats.

Electrochemical behaviour of 5-fluorouracil at electrochemically pre-treated glassy carbon electrode

The right dosage for a medication is crucial and a large dosage accumulation could have an instantaneous effect. Hence for the analysis of concentration of 5-fluorouracil (5-FU) in human blood tissues, an electrochemical sensor was developed using pre-treatment Glassy carbon electrode (GCE) for the efficient detection of 5-FU an anticancer medication, using differential pulse voltammetry (DPV) and cyclic voltammetric (CV) methods. In order to decrease the expense of the suggested sensor, a straightforward surface alteration was made to the GCE. The examination of scan rate, concentration, pH, simultaneous, and interference analysis produced results that were acceptable. Based on the examination of the aforementioned factors, the electrode procedure, the quantity of protons and electrons transferred, the quantification limit for 5-FU was determined and discussed. Thus the developed pre-treated GCE sensor for 5-FU shows promising platform for the investigation of 5-FU with excellent selectivity and sensitivity.

Therapeutic delivery of siRNA for the management of breast cancer and triple-negative breast cancer.

Breast cancer is the leading cause of cancer-related deaths among women globally. The difficulties with anticancer medications, such as ineffective targeting, larger doses, toxicity to healthy cells and side effects, have prompted attention to alternate approaches to address these difficulties. RNA interference by small interfering RNA (siRNA) is one such tactic. When compared with chemotherapy, siRNA has several advantages, including the ability to quickly modify and suppress the expression of the target gene and display superior efficacy and safety. However, there are known challenges and hurdles that limits their clinical translation. Decomposition by endonucleases, renal clearance, hydrophilicity, negative surface charge, short half-life and off-target effects of naked siRNA are obstacles that hinder the desired biological activity of naked siRNA. Nanoparticulate systems such as polymeric, lipid, lipid-polymeric, metallic, mesoporous silica nanoparticles and several other nanocarriers were used for effective delivery of siRNA and to knock down genes involved in breast cancer and triple-negative breast cancer. The focus of this review is to provide a comprehensive picture of various strategies utilized for delivering siRNA, such as combinatorial delivery, development of modified nanoparticles, smart nanocarriers and nanocarriers that target angiogenesis, cancer stem cells and metastasis of breast cancer.

Potential mechanisms underlying podophyllotoxin-induced cardiotoxicity in male rats: toxicological evidence chain (TEC) concept.

Podophyllotoxin (PPT) is a high-content and high-activity compound extracted from the traditional Chinese medicinal plant Dysosma versipellis (DV) which exhibits various biological activities. However, its severe toxicity limits its use. In clinical settings, patients with DV poisoning often experience adverse reactions when taking large doses in a short period. The heart is an important toxic target organ, so it is necessary to conduct 24-h acute cardiac toxicity studies on PPT to understand its underlying toxicity mechanism. Based on the concept of the toxicological evidence chain (TEC), we utilized targeted metabolomic and transcriptomic analyses to reveal the mechanism of the acute cardiotoxicity of PPT. The manifestation of toxicity in Sprague-Dawley rats, including changes in weight and behavior, served as Injury Phenotype Evidence (IPE). To determine Adverse Outcomes Evidence (AOE), the hearts of the rats were evaluated through histopathological examination and by measuring myocardial enzyme and cardiac injury markers levels. Additionally, transcriptome analysis, metabolome analysis, myocardial enzymes, and cardiac injury markers were integrated to obtain Toxic Event Evidence (TEE) using correlation analysis. The experiment showed significant epistaxis, hypokinesia, and hunched posture in PPT group rats within 24h after exposure to 120mg/kg PPT. It is found that PPT induced cardiac injury in rats within 24h, as evidenced by increased serum myocardial enzyme levels, elevated concentrations of cardiac injury biomarkers, and altered cardiac cell morphology, all indicating some degree of cardiac toxicity. Transcriptome analysis revealed that primary altered metabolic pathway was arachidonic acid metabolism after PPT exposure. Cyp2e1, Aldob were positively correlated with differential metabolites, while DHA showed positive correlation with differential genes Fmo2 and Timd2, as well as with heart injury markers BNP and Mb. This study comprehensively evaluated cardiac toxicity of PPT and initially revealed the mechanism of PPT-induced acute cardiotoxicity, which involved oxidative stress, apoptosis, inflammatory response, and energy metabolism disorder.

Dynamics of drug delivery determines course of evolution of antibiotic responses in bacteria.

To adjust to sudden shifts in conditions, microbes possess regulated genetic mechanisms that sense environmental challenges and induce the appropriate responses. The initial evolution of microbes in new environments is thought to be driven by regulatory mutations, but it is not clear how this evolution is affected by how quickly conditions change (i.e. dynamics). Here, we perform experimental evolution on continuous cultures of tetracycline resistant E. coli in different dynamical regimens of drug administration. We find that cultures evolved under gradually increasing drug concentrations acquire fine- tuning mutations adapting an alternative efflux pump to tetracycline. However, cultures that are instead periodically exposed to large drug doses evolve transposon insertions resulting in loss of regulation of the main mechanism of tetracycline resistance. A mathematical model shows that sudden drug exposures overwhelm regulated responses, which cannot induce resistance fast enough. These results help explain the frequent loss of regulation of resistance in clinical pathogens.

The effect of DMSO on Saccharomyces cerevisiae yeast with different energy metabolism and antioxidant status

We studied the effect of dimethyl sulfoxide (DMSO) on the biochemical and physiological parameters of S. cerevisiae yeast cells with varied energy metabolism and antioxidant status. The wild-type cells of varied genetic backgrounds and their isogenic mutants with impaired antioxidant defences (Δsod mutants) or response to environmental stress (ESR) (Δmsn2, Δmsn4 and double Δmsn2msn4 mutants) were used. Short-term exposure to DMSO even at a wide range of concentrations (2–20%) had little effect on the metabolic activity of the yeast cells and the stability of their cell membranes, but induced free radicals production and clearly altered their proliferative activity. Cells of the Δsod1 mutant showed greater sensitivity to DMSO in these conditions. DMSO at concentrations from 4 to 10–14% (depending on the strain and genetic background) activated the ESR programme. The effects of long-term exposure to DMSO were mainly depended on the type of energy metabolism and antioxidant system efficiency. Yeast cells with reduced antioxidant system efficiency and/or aerobic respiration were more susceptible to the toxic effects of DMSO than cells with a wild-type phenotype and respiro-fermentative or fully fermentative metabolism. These studies suggest a key role of stress response programs in both the processes of cell adaptation to small doses of this xenobiotic and the processes related to its toxicity resulting from large doses or chronic exposure to DMSO.