Minimum Effective Dose Research Articles

Minimum effective dose of intrathecal hyperbaric bupivacaine for cesarean section with and without prophylactic norepinephrine infusion: Randomized triple-blinded trial.

Vasopressor usage can affect the rostral spread of intrathecal drug and, hence, its requirement during cesarean delivery. Although a decreased spread is evidenced with phenylephrine, there is no data for norepinephrine usage. The present study aimed to evaluate the minimum effective dose of intrathecal hyperbaric bupivacaine for cesarean section with and without prophylactic norepinephrine infusion. Patients scheduled for elective cesarean section under combined spinal-epidural block were randomized to receive intravenous infusion of norepinephrine (0.05 μg/kg/min) or normal saline (placebo), initiated immediately after intrathecal injection. Postspinal hypotension in either group (systolic arterial pressure ≤0.8 baseline) was treated with norepinephrine 4 μg rescue. Dose of intrathecal hyperbaric bupivacaine (0.5%) was decided for individual patients using up-and-down sequential allocation method. Primary outcome measure was the minimum effective dose of intrathecal hyperbaric bupivacaine (0.5%) defined as ED50, while secondary observations included spinal block characteristics and neonatal outcomes. Demographic parameters were statistically similar between both groups (P > 0.05). ED50 of intrathecal hyperbaric bupivacaine was 7.8 mg (95% confidence interval [CI]: 6.7-8.8) and 7.4 mg (95% CI: 6.1-8.7) for normal saline and norepinephrine group respectively (P = 0.810). Block characteristics were similar between both groups as was neonatal APGAR score, but umbilical artery base excess was greater for norepinephrine versus normal saline group (-4.4 ± 3.6 vs. -6.5 ± 2.4, P = 0.038). Use of prophylactic norepinephrine (0.05 μg/kg/min) during cesarean delivery does not require adjustment of intrathecal hyperbaric bupivacaine.

THE FOCUS ON INCREASED RISK OF FRACTURES IN THEIR PROLONGED USE

Proton pump inhibitors are the most effective drugs for the treatment of acid-dependent diseases. For a long time, proton pump inhibitors have been considered to be completely safe drugs both for short-term and long-term use. A number of modern clinical studies note that when prescribing proton pump inhibitors in high doses for a long time, the possibility of side effects should be taken into account. The purpose of the review is to study the effect of prolonged use of proton pump inhibitors on the condition of bone tissue and the risk of osteoporotic fractures. Materials and methods. A search was conducted in the PubMed and Scopus information databases for publications on the safety of using proton pump inhibitors, including sources published before December 1, 2023, with an emphasis on the influence of proton pump inhibitors on bone tissue and the possible risk of fractures. Results. According to numerous studies, prolonged use of proton pump inhibitors is associated with an increased risk of fractures of the hip, vertebrae and the wrist. An increased risk of fractures may be associated with hypergastrinemia and hypochlorhydria (due to inhibition of acid secretion by proton pump inhibitors), and electrolyte disorders (hypocalcemia). Conclusions. All the pros and cons of prescribing proton pump inhibitors in patients with a history of fractures associated with osteoporosis should be carefully considered. In the curation of comorbid/multimorbid patients, proton pump inhibitors should be used if medically required for as short duration as possible and at the minimum effective dose to relieve symptoms.

BET inhibitor nanotherapy halts kidney damage and reduces chronic kidney disease progression after ischemia-reperfusion injury

Targeting epigenetic mechanisms has emerged as a potential therapeutic approach for the treatment of kidney diseases. Specifically, inhibiting the bromodomain and extra-terminal (BET) domain proteins using the small molecule inhibitor JQ1 has shown promise in preclinical models of acute kidney injury (AKI) and chronic kidney disease (CKD). However, its clinical translation faces challenges due to issues with poor pharmacokinetics and side effects. Here, we developed engineered liposomes loaded with JQ1 with the aim of enhancing kidney drug delivery and reducing the required minimum effective dose by leveraging cargo protection. These liposomes efficiently encapsulated JQ1 in both the membrane and core, demonstrating superior therapeutic efficacy compared to freely delivered JQ1 in a mouse model of kidney ischemia-reperfusion injury. JQ1-loaded liposomes (JQ1-NPs) effectively targeted the kidneys and only one administration, one-hour after injury, was enough to decrease the immune cell (neutrophils and monocytes) infiltration to the kidney—an early and pivotal step to prevent damage progression. By inhibiting BRD4, JQ1-NPs suppress the transcription of pro-inflammatory genes, such as cytokines (il-6) and chemokines (ccl2, ccl5). This success not only improved early the kidney function, as evidenced by decreased serum levels of BUN and creatinine in JQ1-NPs-treated mice, along with reduced tissue expression of the damage marker, NGAL, but also halted the production of extracellular matrix proteins (Fsp-1, Fn-1, α-SMA and Col1a1) and the fibrosis development. In summary, this work presents a promising nanotherapeutic strategy for AKI treatment and its progression and provides new insights into renal drug delivery.

Abstract 4607: Targeted nanoparticle delivery of irinotecan and Ewing sarcoma-specific siRNA is an effective combination therapy for Ewing sarcoma

Abstract Background: Ewing sarcoma (ES) is an aggressive bone and soft tissue tumor affecting children and adolescents with an overall survival rate of 50%. Irinotecan (IR) is an effective chemotherapeutic agent but is associated with significant toxicity. Using an anti-CD99 targeted hybrid polymerized lipid nanoparticle containing IR, NV103, in pre-clinical mouse xenograft model of the disease, tumor ablation was achieved at 2mg/kg of IR versus 50mg/kg for free IR. All ES harbor a chromosomal translocation resulting in expression of a fusion EWS-FLI1 protein or equivalent. This chimeric gene is a transcriptional regulator that upregulates the FEZF1 and FEZF1-AS1 genes. Both EWS-FLI1 and FEZF1-AS1 genes are unique to ES and are not expressed in normal adult tissues. EWS-FLI1 promotes cell growth while the FEZF1-AS1 complex promotes tumor metastasis, a hallmark of ES. In vitro RNAi targeting of EF and FEZF1-AS1 results in tumor cell death. We hypothesized that combining EWS-FLI1 and/or FEZF1-AS1 targeted RNAi therapy with NV103 cytotoxic therapy would be more effective than any single modality therapy. Methods: NV103 was provided by NanoValent Pharmaceuticals. siRNA containing lipid nanoparticles (LNP-siRNA) were generated using PreciGenome NanoGenerator. siRNA was quantified using the ribogreen assay. Nanoparticles were analyzed for size and particle numbers by NanoSight. siRNA was used to target the following genes- EWS-FLI1, FEZF1, FEZF1-AS1, or GFP. A673 cells expressing GFP were used for this in vitro study. Various doses of IR and siRNA were used in combination and cell growth/death was imaged live using Incucyte. ATP assay was used to confirm live cells and to determine minimum effective dose (MED) over 72 hours of treatment. Results: LNP-siRNA, mean diameter 70nm and PDI<0.2, encapsulated 90% of the siRNA in solution. LNP are stable at 4°C for at least 4 weeks with minimal-to-no loss of activity. NV103 had a MED of 1µM. MED of various siRNA was 30 to 50nM. Combination of NV103 and LNP-siRNA reduced MED of IR to 250nM. One treatment dose of LNP-siRNA followed by NV103 treatment three days later maintained significant cell death over 10 days post treatment initiation. Control cells were 97% more confluent than NV103/EWS-FLI1 siRNA treated ones, 85% more than NV103/FEZF1 siRNA cells and 92% more than NV103/FEZF1-AS1 treated cells. siRNA combinations of EWS-FLI1 and FEZF1 or FEZF1-AS1 along with NV103 added no further benefit. Conclusion: Combination nanoparticle therapy of IR and ES-specific siRNA reduces IR MED by four-fold. LNP delivery of siRNA enables tumor-specific gene targeting. Most have no available small molecule therapy. Targeting ES cells with both a low dose (250nM) of IR and 30-50nM of siRNA against unique tumor biomarkers results in increased cell death with no IR toxicity. Further animal studies are required to determine the effectiveness of such therapy in vivo. Citation Format: Sheetal A. Mitra, Jean-Hugues Parmentier, Hyung-Gyoo Kang, Timothy J. Triche. Targeted nanoparticle delivery of irinotecan and Ewing sarcoma-specific siRNA is an effective combination therapy for Ewing sarcoma [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 4607.

Abstract 3206: Tumor-targeted nanoparticles for cancer therapy

Abstract Introduction: Untargeted cancer therapy is often toxic, limiting the maximum tolerated dose (MTD) and thus potential cure. Targeted therapy with antibody-drug conjugates (ADCs) has demonstrated greater efficacy, as with those directed at HER2 for triple negative breast cancer and other HER2 expressing tumors. However, ADC drug-antibody ratio (DAR) is limited, typically 3 to 1. In contrast, antibody-targeted nanoparticles deliver thousands of drug molecules per nanoparticle, with potentially greater anti-tumor effect. Experimental Procedures: Antibody targeted nanoparticles (TNP) were created that preferentially deliver cytotoxic molecules to tumor cells. TNPs were created with various antibodies and payloads and evaluated for their efficacy against 12 different adult and pediatric malignancies (see below), using tumor xenografts in NOG-SCID mice. Survival of control, free drug, and TNP treated animals was compared. MED was also determined. Non-tumor bearing animals treated at the same dose and schedule were evaluated for evidence of toxicity. PK/PD metrics were obtained and drug delivery to normal and tumor tissue was evaluated microscopically and by mass spectroscopy. Data: Plasma TNP drug levels persist for 48 hours, compared to free drug which is undetectable by 2 hours. Microscopically, nanoparticles accumulate in tumor tumor tissue but not normal tissue. Drug levels are typically 15 times higher in tumor tissue than normal tissue by quantitative mass spectroscopy. The minimum effective dose (MED) is reduced 25-fold for Ewing sarcoma, from 50 mg/kg to 2 mg/kg. TNPs also cross the blood-brain barrier (BBB), and were used to treat orthotopic GBM PDX xenografts, prolonging animal survival 3-fold over control or free drug treated animals. Ewing sarcoma, osteosarcoma, triple negative breast cancer, GBM, hepatoma, and adult ALL, bearing animals all showed complete tumor ablation and 100% survival when treated biweekly at 10mg/kg. Pancreatic, prostate, and ovarian Ca showed 100% survival in TNP treated mice after all control animals had died but remained tumor bearing with slow but progressive tumor growth when treated identically. Lung and colorectal Ca and melanoma bearing animals treated similarly with TNPs showed 50-80% survival at the time of control animal death. No animal in any study showed evidence of off-target toxicity. Conclusions: Tumor antigen targeted, cytotoxic molecule containing nanoparticles have been created that show broad utility in the treatment of at least a dozen different adult and pediatric cancers. Six of 12 types showed complete tumor ablation when treated at 10mg/kg biweekly injections, and the remainder showed enhanced anti-tumor effect and survival compared to free drug treatment. We conclude that use of tumor antigen targeted, small molecule cytotoxic containing nanoparticles results in dramatically enhanced tumor response and in many case, complete tumor ablation where the same free drug fails to do so. Citation Format: HyungGyoo Kang, Bryon Upton, Jon Nagy, Timothy Triche. Tumor-targeted nanoparticles for cancer therapy [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 3206.

Abstract 394: Preclinical evaluation of ERX-208, a potent inducer of ER stress for the treatment of ovarian cancer

Abstract Background: Ovarian cancer (OCa) is the deadliest kind of gynecologic cancer in the United States. The long-term survival rate for OCa is less than 20% after five years. Intra-tumoral and inter-tumoral heterogeneity is implicated in tumor resistance to conventional therapies and the unsatisfactory clinical outcomes. Addressing these issues necessitates innovative therapies that target intrinsic common vulnerabilities within OCa. Recent studies have highlighted that high basal level of endoplasmic reticulum stress (ERS) in OCa as a critical vulnerability. We have identified a promising compound, ERX-208 that potently induces ERS in cancer cells. The objective of this study is to characterize the mechanisms and activity of ERX-208 using preclinical models. Methods: The biological activity of ERX-208 was examined across 17 distinct OCa cells, representing 5 diverse OCa subtypes. Mechanistic studies utilized Western blotting, immunohistochemistry (IHC), RNA-Seq analysis, and CRISPR/Cas9 knockouts (KO). Pharmacokinetics (PK) and toxicity studies were performed on C57BL/6 mice. Comprehensive preclinical assessments were carried out through cell line-derived xenografts (CDXs), patient-derived xenografts (PDXs), organoids (PDOs) and explants (PDEs). Results: ERX-208 demonstrated an IC50 of approximately 50-100 nM inducing ERS and reducing cell viability in OCa cells. Conversely, normal ovarian surface epithelial cells exhibited minimal effects from ERX-208. In vitro experiments revealed strong ERX-208-induced apoptosis in OCa cell lines. Mechanistic studies employing RNA sequencing, Western blotting, and RT-qPCR, confirmed activation of ERS pathways observed as early as 5 hours post-ERX-208 treatment. Our studies identified LIPA as a potential target, and KO of LIPA significantly diminished ERX-208 activity. Moreover, LIPA KO substantially impeded in vivo OCa tumor growth. ERX-208 up to a dose of 25 mg/kg showed no observable organ toxicity and had no effect on the mice's body weight. Dose range studies identified 10 mg/kg intraperitoneal as the minimal effective dose, achieving more than 50% tumor reduction. In preclinical models, ERX-208 inhibited the growth of OCa CDXs, PDXs, and ex vivo PDEs and PDO’s. IHC analyses indicated reduced proliferation (Ki-67) and increased activation of ERS markers, such as GRP78 and p-PERK. Conclusions: Collectively, our findings underscore the preclinical promise of ERX-208 as a potential therapeutic agent for treating OCa. Conflict: The patents surrounding ERX-208 are licensed to EtiraRx. Citation Format: Suryavathi Viswanadhapalli, Tae-Kyung Lee, Scott Elmore, Gaurav Sharma, Rahul Gopalam, Karla Parra, Tanner Reese, Michael Hsieh, Uday P. Pratap, Xue Yang, Behnam Ebrahimi, Henry Neal, Chia-Yuan Chen, Kara Kassees, Christian Cervantes, Zhenming Xu, Edward Kost, Gangadhara Reddy Sareddy, Rajeshwar R. Tekmal, Jung-Mo Ahn, Ganesh V. Raj, Ratna K. Vadlamudi. Preclinical evaluation of ERX-208, a potent inducer of ER stress for the treatment of ovarian cancer [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 394.

Abstract 2622: TUB-040, a novel Napi2b-targeting ADC built with ethynylphosphonamidate conjugation chemistry, demonstrates high and long-lasting anti-tumor efficacy via Topoisomerase-I inhibition and excellent tolerability predictive of a wide therapeutic window in humans

Abstract TUB-040 is a novel Antibody-Drug Conjugate (ADC) targeting Napi2b, a highly overexpressed target in ovarian cancer and lung adenocarcinoma. Napi2b is a member of the solute-carrier transporter family with eight transmembrane domains and an antibody-accessible extracellular loop, that regulates sodium-dependent phosphate homeostasis. Ethynylphosphonamidate conjugation chemistry was used to build TUB-040 with a homogenous DAR (drug-antibody-ratio) of 8 and the Topoisomerase I inhibitor Exatecan as payload, which is connected to a humanized, Fc-silenced IgG1 antibody targeting Napi2b using a cleavable linker system. In vitro, TUB-040 is characterized by sub-nanomolar affinity and specific binding to Napi2b, efficient target-mediated internalization and high cytotoxicity towards Napi2b-expressing ovarian and lung cancer cell lines as well as bystander activity against co-cultured target-negative cells. TUB-040 induces DNA damage and apoptosis in a dose-dependent fashion as well as markers of immunogenic cell death. In addition, no unspecific uptake and cytotoxicity in healthy, target-negative human cells could be detected, reducing the risk of target-independent toxicities. Pharmacokinetic analysis showed that - in contrast to maleimide-conjugated ADCs - TUB-040 is highly stable - and does not lose or transfer its linker-payload to serum proteins during blood circulation, thus enabling most efficient and continued delivery of Exatecan to the tumor. Across a variety of cell line derived xenograft (CDX) and patient derived xenograft (PDX) models of ovarian and non-small cell lung cancer, including models with low target expression, single dose administration of TUB-040 results in long-lasting tumor growth inhibition with high complete remission rates in vivo. The minimally effective dose (MED) leading to complete remission is 1 mg/kg. Preliminary repeat-dose toxicological assessment of TUB-040 in the pharmacologically relevant species cynomolgus monkey demonstrated that TUB-040 is well tolerated with no signs of lung toxicity and thrombocytopenia. Allometric scaling and PK/PD modelling predicts a human serum half-life greater 10 days and a therapeutic index in humans up to 55. Based on these results, TUB-040, designed with differentiating technology for optimal efficacy and tolerability, is ready for testing in clinical trials. Citation Format: Saskia Schmitt, Isabelle Mai, Paul Machui, Sarah Herterich, Danila Hauswald, Philipp Ochtrop, Philipp Cyprys, Izabela Kozlowska, Annabel Kitowski, Marcus Gerlach, Olivier Marcq, Pamela A. Trail, Dominik Schumacher, Marc-André Kasper, Günter Fingerle-Rowson, Björn Hock, Jonas Helma-Smets, Annette M. Vogl. TUB-040, a novel Napi2b-targeting ADC built with ethynylphosphonamidate conjugation chemistry, demonstrates high and long-lasting anti-tumor efficacy via Topoisomerase-I inhibition and excellent tolerability predictive of a wide therapeutic window in humans [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 2622.

Perspectives About Ascorbic Acid to Treat Inflammatory Bowel Diseases.

It is known that reactive oxygen species cause abnormal immune responses in the gut during inflammatory bowel diseases (IBD). Therefore, oxidative stress has been theorized as an agent of IBD development and antioxidant compounds such as vitamin C (L-ascorbic acid) have been studied as a new tool to treat IBD. Therefore, the potential of vitamin C to treat IBD was reviewed here as a critical discussion about this field and guide future research. Indeed, some preclinical studies have shown the beneficial effects of vitamin C in models of ulcerative colitis in mice and clinical and experimental findings have shown that deficiency in this vitamin is associated with the development of IBD and its worsening. The main mechanisms that may be involved in the activity of ascorbic acid in IBD include its well-established role as an antioxidant, but also others diversified actions. However, some experimental studies employed high doses of vitamin C and most of them did not perform dose-response curves and neither determined the minimum effective dose nor the ED50. Allometric extrapolations were also not made. Also, clinical studies on the subject are still in their infancy. Therefore, it is suggested that the research agenda in this matter covers experimental studies that assess the effective, safe, and translational doses, as well as the appropriate administration route and its action mechanism. After that, robust clinical trials to increase knowledge about the role of ascorbic acid deficiency in IBD patients and the effects of their supplementation in these patients can be encouraged.

BAER-101, a selective potentiator of α2- and α3-containing GABAA receptors, fully suppresses spontaneous cortical spike-wave discharges in Genetic Absence Epilepsy Rats from Strasbourg (GAERS).

BAER-101 (formerly AZD7325) is a selective partial potentiator of α2/3-containing γ-amino-butyric acid A receptors (GABAARs) and produces minimal sedation and dizziness. Antiseizure effects in models of Dravet and Fragile X Syndromes have been published. BAER-101 has been administered to over 700 healthy human volunteers and patients where it was found to be safe and well tolerated. To test the extent of the antiseizure activity of BAER-1010, we tested BAER-101 in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS) model, a widely used and translationally relevant model. GAERS rats with recording electrodes bilaterally located over the frontal and parietal cortices were used. Electroencepholographic (EEG) signals in freely moving awake rats were analyzed for spike-wave discharges (SWDs). BAER-101 was administered orally at doses of 0.3-100 mg/kg and diazepam was used as a positive control using a cross-over protocol with a wash-out period between treatments. The number of SWDs was dose-dependently reduced by BAER-101 with 0.3 mg/kg being the minimally effective dose (MED). The duration of and total time in SWDs were also reduced by BAER-101. Concentrations of drug in plasma achieved an MED of 10.1 nM, exceeding the Ki for α2 or α3, but 23 times lower than the Ki for α5-GABAARs. No adverse events were observed up to a dose 300×MED. The data support the possibility of antiseizure efficacy without the side effects associated with other GABAAR subtypes. This is the first report of an α2/3-selective GABA PAM suppressing seizures in the GAERS model. The data encourage proceeding to test BAER-101 in patients with epilepsy.

A novel, small anti-HBV compound reduces HBsAg and HBV-DNA by destabilizing HBV-RNA.

Currently, standard treatments for chronic hepatitis B such as nucleos(t)ide analogs (NAs), effectively reduce hepatitis B virus (HBV) loads but rarely result in a functional cure (defined as sustained HBsAg loss). We report the discovery of a novel, 4-pyridone compound, SAG-524, a potent and orally bioavailable small molecule inhibitor of HBV replication. The antiviral characteristics and selectivity of SAG-524 and its derivative compound against HBV were evaluated in HBV-infection assays and HBV-infected chimeric urokinase-type plasminogen activator/severe combined immunodeficiency mice with humanized livers (PXB mice), alone or in combination with entecavir. Toxicity studies were conducted in mice and monkeys. SAG-524 reduced HBV-DNA (IC50 = 0.92nM) and HBsAg (IC50 = 1.4nM) in the supernatant of the HepG2.2.15 cells. SAG-524 selectively destabilized HBV-RNA via PAPD5, but not GAPDH or albumin mRNA, by shortening the poly(A) tail. PAPD5 may also be involved in HBV regulation via ELAVL1. In a study of HBV-infected PXB mice, SAG-524 produced potent reductions of serum HBsAg and HBcrAg, and the minimum effective dose was estimated to be 6mg/kg/day. The combination therapy with entecavir greatly reduced HBsAg and cccDNA in the liver due to reduction of human hepatocytes with good tolerability. Administration of SAG-524 to monkeys, up to 1000mg/kg/day for two weeks, led to no significant toxicity, as determined by blood tests and pathological images. We have identified SAG-524 as novel and orally bioavailable HBV-RNA destabilizers which can reduce HBsAg and HBV-DNA levels, and possibly contribute a functional cure.

TLC-Bioautography-Guided Isolation and Assessment of Antibacterial Compounds from Manuka (Leptospermum scoparium) Leaf and Branch Extracts.

A rapid procedure for the targeted isolation of antibacterial compounds from Manuka (Leptospermum scoparium) leaf and branch extracts was described in this paper. Antibacterial compounds from three different Manuka samples collected from New Zealand and China were compared. The active compounds were targeted by TLC-bioautography against S. aureus and were identified by HR-ESI-MS, and -MS/MS analysis in conjunction with Compound Discoverer 3.3. The major antibacterial component, grandiflorone, was identified, along with 20 β-triketones, flavonoids, and phloroglucinol derivatives. To verify the software identification, grandiflorone underwent purification via column chromatography, and its structure was elucidated through NMR analysis, ultimately confirming its identity as grandiflorone. This study successfully demonstrated that the leaves and branches remaining after Manuka essential oil distillation serve as excellent source for extracting grandiflorone. Additionally, we proposed an improved TLC-bioautography protocol for evaluating the antibacterial efficacy on solid surfaces, which is suitable for both S. aureus and E. coli. The minimum effective dose (MED) of grandiflorone was observed to be 0.29-0.59 μg/cm2 against S. aureus and 2.34-4.68 μg/cm2 against E. coli, respectively. Furthermore, the synthetic plant growth retardant, paclobutrazol, was isolated from the samples obtained in China. It is hypothesized that this compound may disrupt the synthesis pathway of triketones, consequently diminishing the antibacterial efficacy of Chinese Manuka extract in comparison to that of New Zealand.

Unraveling the gut health puzzle: exploring the mechanisms of butyrate and the potential of High-Amylose Maize Starch Butyrate (HAMSB) in alleviating colorectal disturbances.

Colorectal disturbances encompass a variety of disorders that impact the colon and rectum, such as colitis and colon cancer. Butyrate, a short-chain fatty acid, plays a pivotal role in supporting gut health by nourishing colonocytes, promoting barrier function, modulating inflammation, and fostering a balanced microbiome. Increasing colorectal butyrate concentration may serve as a critical strategy to improve colon function and reduce the risk of colorectal disturbances. Butyrylated high-amylose maize starch (HAMSB) is an edible ingredient that efficiently delivers butyrate to the colon. HAMSB is developed by esterifying a high-amylose starch backbone with butyric anhydride. With a degree of substitution of 0.25, each hydroxy group of HAMSB is substituted by a butyryl group in every four D-glucopyranosyl units. In humans, the digestibility of HAMSB is 68% (w/w), and 60% butyrate molecules attached to the starch backbone is absorbed by the colon. One clinical trial yielded two publications, which showed that HAMSB significantly reduced rectal O6-methyl-guanine adducts and epithelial proliferation induced by the high protein diet. Fecal microbial profiles were assessed in three clinical trials, showing that HAMSB supplementation was consistently linked to increased abundance of Parabacteroides distasonis. In animal studies, HAMSB was effective in reducing the risk of diet- or AOM-induced colon cancer by reducing genetic damage, but the mechanisms differed. HAMSB functioned through affecting cecal ammonia levels by modulating colon pH in diet-induced cancer, while it ameliorated chemical-induced colon cancer through downregulating miR19b and miR92a expressions and subsequently activating the caspase-dependent apoptosis. Furthermore, animal studies showed that HAMSB improved colitis via regulating the gut immune modulation by inhibiting histone deacetylase and activating G protein-coupled receptors, but its role in bacteria-induced colon colitis requires further investigation. In conclusion, HAMSB is a food ingredient that may deliver butyrate to the colon to support colon health. Further clinical trials are warranted to validate earlier findings and determine the minimum effective dose of HAMSB.

BNC210, a negative allosteric modulator of the alpha 7 nicotinic acetylcholine receptor, demonstrates anxiolytic- and antidepressant-like effects in rodents

This work describes the characterization of BNC210 (6-[(2,3-dihydro-1H-inden-2-yl)amino]-1-ethyl-3-(4-morpholinylcarbonyl)-1,8-naphthyridin-4(1H)-one), a selective, small molecule, negative allosteric modulator (NAM) of α7 nicotinic acetylcholine receptors (α7 nAChR). With the aim to discover a non-sedating, anxiolytic compound, BNC210 was identified during phenotypic screening of a focused medicinal chemistry library using the mouse Light Dark (LD) box to evaluate anxiolytic-like activity and the mouse Open Field (OF) (dark) test to detect sedative and/or motor effects. BNC210 exhibited anxiolytic-like activity with no measurable sedative or motor effects. Electrophysiology showed that BNC210 did not induce α7 nAChR currents by itself but inhibited EC80 agonist-evoked currents in recombinant GH4C1 cell lines stably expressing the rat or human α7 nAChR. BNC210 was not active when tested on cell lines expressing other members of the cys-loop ligand-gated ion channel family. Screening over 400 other targets did not reveal any activity for BNC210 confirming its selectivity for α7 nAChR. Oral administration of BNC210 to male mice and rats in several tests of behavior related to anxiety- and stress- related disorders, demonstrated significant reduction of these behaviors over a broad therapeutic range up to 500 times the minimum effective dose. Further testing for potential adverse effects in suitable rat and mouse tests showed that BNC210 did not produce sedation, memory and motor impairment or physical dependence, symptoms associated with current anxiolytic therapeutics. These data suggest that allosteric inhibition of α7 nAChR function may represent a differentiated approach to treating anxiety- and stress- related disorders with an improved safety profile compared to current treatments.

New immunomodulatory preparations based on RNA to treat viral infections

New experimental antiviral preparations are developed based on a molecular structure consisting of single-stranded and double-stranded RNAs from different sources and an outer envelope based on dextran with specific isotropic agents. An affection of developed molecular structure preparations on physiological indicators variety in laboratory animals to obtain data on the tolerance of compositions was investigated. It has been shown that administering higher doses of experimental preparations to animals doesn`t cause or lead to short-term and minor deviations in their condition. An application of the method of specific interferon-inducing activity determining in the study of antiviral and other interferon inducers characteristics may be used for estimation of criteria like the minimal effective interferon-inducing dose (MEID) and the modified chemotherapeutical index (mCTI), required for a complete characterisation of drugs.

Therapy of mental disorders in patients with hematological malignancies

To assess the possibilities of therapy with minimal effective doses (MED) of psychotropic drugs for mental disorders (MD) that manifest during the treatment of hematological malignancies (HM). A prospective study was conducted at the National Medical Research Center for Hematology of the Russian Ministry of Health (Moscow), which included 204 (39.4%) men and 314 (60.6%) women (518 patients in total), aged 17 to 83 years (median 45 years), with various HM, in which the manifestation of MD occurred during the treatment of the underlying disease. To minimize the side-effects of psychotropic drugs and given the relatively mild level of MD, psychopharmacotherapy of patients was carried out mainly at MED. The severity of MD, manifested in patients, was assessed by the illness severity scale of the Clinical Global Impression (CGI) scale, and the effectiveness of the treatment was assessed by the improvement scale (CGI-I). Mainly mild (188, 36%) and moderately pronounced (270, 52%) MD were noted in patients with HM during the treatment of the underlying disease. Severe psychopathological disorders (60, 12%) were observed much less often. Because of psychopharmacotherapy with MED, patients experienced a very significant (97, 19%) and significant improvement (354, 68%) of their mental state, less often the improvement was regarded as minimal (67, 13%). Therefore, almost all patients showed a stable relief of MD; in 87% (95% CI 84-90) of patients, this improvement was significant. The tactics of treatment MD that manifest in patients with HM with MED of psychotropic drugs turned out to be therapeutically effective according to the results of the assessment on CGI scales.

Identifying Therapeutic Window for the Ratio of Means under Heteroscedasticity

In efficacy and safety studies, a vital research concern is to determine the therapeutic window of a pharmaceutical compound. The approach to finding minimum effective dose and maximum safe dose involves multiple comparisons. Generally, in such a problem, a family‐wise error rate is inherited if multiplicity adjustment is not handled properly. This article without a need for multiplicity adjustment formulates a stepwise confidence interval method to identify a therapeutic window of a pharmaceutical compound when equality of variances cannot be assumed and when ratios of variances are known. This article employed Fieller’s method and obtained individual confidence intervals for the identification of the minimum effective dose and maximum safe dose. A simulation study was performed and the results show that the confidence interval method proposed in this article controls the family‐wise error rate strongly. Power increases whenever the ratio of means increases and decreases against higher clinical relevance margins. The proposed procedure was applied to real data and provided optimum results. It was also observed that as both the ratio of means and the sample sizes increase, power increases accordingly.

Catheter-based examination for pulmonary microcirculatory function in patients with pulmonary hypertension.

A device that can evaluate human pulmonary microcirculation is currently unavailable. This study aimed to establish a novel approach for assessing pulmonary microcirculation in patients with pulmonary hypertension (PH). We used a guidewire embedded with temperature and pressure sensors to measure the following pulmonary microcirculatory function indicators: pulmonary flow reserve, pulmonary index of microcirculatory resistance (PIMR), and pulmonary resistive reserve ratio. Adenosine was administered to patients to induce hyperemia in the pulmonary artery for assessment. The correlation between these indicators and various parameters, including serum biomarkers, hemodynamic and respiratory functions, and exercise capacity, were examined. The procedure was performed in 19 patients with moderate PH, without major complications. The minimum effective adenosine dosage for maximal hyperemia, without severe side effects, was 150 μg∙kg-1∙min-1. Multivariate stepwise analysis revealed a positive correlation between the hyperemic PIMR and serum uric acid (p < 0.001) and N-terminal probrain natriuretic peptide levels (p = 0.014). Therefore, this catheter-based method offers an effective means to assess pulmonary microcirculatory function in patients with PH, and the optimal dose of adenosine for this evaluation was 150 μg∙kg-1∙min-1.

The use of D- and L,D- cloprostenol to reduce diastral period of estrus cycle in mares

In order to determine the minimum effective drug doses, the levels of decrease in progesterone concentration followed the injections of D and L, D - cloprostenol (the dosage 25 - 250 μg) were compared. The effect of treatment on the reduction of estrus duration and the time before ovulation were studied. It has been shown that the level of progesterone 24 hours after the first injection (at any dose except 50 μg of L, Dcloprostenol) decreased by 76-81%. Complete luteolysis was achieved (0.24-0.45 ng/ml) at any kind of treatment in 72 hours after injection. A significant difference in the average duration of estrus (when using large doses) and the period from injection to ovulation (when using small and large doses) was found between groups of mares that were injected with a follicle diameter of 22-28 or 29-37 mm in both the first and in the second half of diestrus. The study showed that the use of D-cloprostenol once in reduced doses (25 - 50 μg) or D, L-cloprostenol twice 50 μl in the presence of follicles more than 29 mm in diameter will decrease the risk of reducing the duration of estrus.

Simulation of excess lifetime cancer risk due to the presence of radon in groundwater in Wamba town of Wamba local government area, Nasarawa state, Nigeria

The measurements of Radon concentration in ten groundwater (4-wells and 6-boreholes) from Wamba town of Wamba Local Government Area of Nigeria had been carried out. The annual effective dose (AED) and the Excess Lifetime Cancer Risk (ELCR) due to ingestion of the groundwater was established to ascertain the risk outcome from the samples. Radon concentration was detected using RAD7. The minimum Radon concentration was 0.146 Bql-1 while the maximum was 0.474 Bql-1 with mean average of 0.3134 Bql-1 which are within the United States Environmental Protection Agencies (USEPA) 11.1 Bq/L recommendation. Moreso, the maximum and minimum Annual Effective Dose (AEDing) was 3.5×10^(-6) and 1.10×10^(-6) Sv/yr which are also within the 0.1 mSv/yr World Health Organization (WHO) recommendation, while the maximum and minimum Excess Lifetime Cancer Risk (ELCR) was 1.44×10^(-5) and 4.50×10^(-6) respectively. Cumulative probability simulation of the Excess Lifetime Cancer Risk (ELCR) was carried out using Oracle Crystal Ball software validated by 10 and 90% percentiles. Comparison of all the results with the European Union (EU)/World Health Organization (WHO) value of 500 Bq/L recommendation revealed that all the samples analyzed have Radon concentration below the recommended limit. The average mean Radon concentration in the ten locations from Wamba Town are within the recommended levels as confirmed by the simulation results. At 10% Probability, the highest risk was found in Event center (1.26×10^(-5)) while the lowest was found in the water sample collected from Angwan dalatu (1.05×10^(-6)) while at 90% probability the highest (1.62×10^(-5)) and lowest (1.37×10^(-6)) risk was found in the same Events center and Angwan dalatu. Though there is variation in the results based on locations which means that the concentration of Radon gas depends on the geological nature of the bedrock and generally increases with the uranium concentration in the local geology. The Excess Lifetime Cancer Risk (ELCR) dose results are far lower than the UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiations) recommended maximum contamination level of 0.003875. Therefore, no indication of any likelihood of cancer incidence as a result of waterborne radon within the studied community that may demand urgent intervention from radiological point of view.

Epidermal Growth Factor Receptor Inhibition With Erlotinib in Liver: Dose De-Escalation Pilot Trial as an Initial Step in a Chemoprevention Strategy

Background and AimsEffective approaches for prevention of hepatocellular carcinoma (HCC) will have a significant impact on HCC-related mortality. There are strong preclinical data and rationale to support targeting epidermal growth factor receptor (EGFR) for HCC chemoprevention. Small molecule inhibitors of EGFR have been FDA-approved for cancer therapy, which provides an opportunity to re-purpose one of these drugs for chemoprevention of HCC. Unfortunately, the frequency of side-effects associated with administration of these drugs at oncology doses renders them ineffective for chemoprevention. This clinical trial assesses whether lower doses of one of these inhibitors, erlotinib, still engages EGFR in the liver to block signaling (e.g. EGFR phosphorylation). The objective of this clinical trial was determination of a safe and minimum effective dose of erlorinib for which ≥50% reduction phospho-EGFR immunohistochemical staining in the liver was observed. Methods46 participants were pre-registered and 25 participants were registered in this multicenter trial. By dose de-escalation trial design, cohorts of participants received a 7-day course of erlotinib 75 mg/day, 50 mg/day or 25 mg/day with liver tissue acquisition prior to and after erlotinib. ResultsA ≥50% reduction phospho-EGFR immunohistochemical staining in the liver was observed in a minimum of 40% of participants (predetermined threshhold) at each of the dose levels. Erlotinib was very well tolerated with few side effects observed, particularly at the dose of 25 mg/day. Favorable modulation of the Prognostic Liver Signature was observed in participants that received erlotinib. ConclusionsThese data support the selection of erlotinib doses as low as 25 mg/day of for a longer intervention to assess for evidence of efficacy as an HCC chemoprevention drug. (ClinicalTrials.gov NCT02273362)