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Simple Summary: Feeding sloths (Bradypus sp.) in captivity can be extremely challenging due to their individually selective folivorous diet and preferences for specific plant species. This selectivity complicates nutritional management and can lead to diseases associated with an unbalanced diet. By using an in vitro fermentation technique, we evaluated the nutritional characteristics of three feeds for captive sloths by incubating samples of these feeds with the stomach contents of sloths. Our findings indicate that the leaves of plants from the genera Pterodon sp. and Inga sp. show potential for feeding Bradypus variegatus sloths in captivity, with particular emphasis on the former, which demonstrated the best results for protein digestibility, fiber digestion rates, and total fermentation gas volume. We recommend careful attention to the fiber content of Cecropia sp. plants due to possible negative effects on dry matter intake. It is suggested that this plant be fed in combination with other feeds containing less fiber to allow for selection by the animals. This study aimed to evaluate the nutritive value of three feeds (Cecropia sp., Pterodon sp., and Inga sp.) for sloths (Bradypus variegatus), based on nutritional composition and in vitro gas production. After a 14-day adaptation period to these feeds, approximately 500 g of gastric contents were collected from three female sloths, processed, and incubated with the food samples to evaluate digestibility and in vitro degradation kinetics. Regarding the nutritional composition, the neutral detergent fiber (NDFcp) content was higher with 404 g kg−1 DM (p = 0.001) in the leaves of Cecropia sp. The non-fibrous carbohydrate contents were greater with 499 g kg−1 DM in Pterodon sp. (p = 0.002). The greatest cellulose content (211 g kg−1 DM) was found in the leaves of C. pachystachya, as well as the lowest value of 143 g kg−1 DM for hemicellulose. Significant differences in the in vitro digestibility of crude protein (p = 0.041) were observed, with Inga sp. showing the highest value at 547 g kg−1 DM. In terms of kinetic parameters, Pterodon sp. exhibited higher total gas production (Vt) at 99 mL (p = 0.023) and digestion rates of fibrous carbohydrates (kdFC) at 0.0223%/h (p = 0.020) (p < 0.05). The leaves of Pterodon sp. and Inga sp. showed potential as suitable feeds for B. variegatus, while Cecropia sp. may have negative effects on dry matter intake due to its high NDF content, because of possible repletion effects on the stomach. [ABSTRACT FROM AUTHOR]

Objective: .In this study, we investigated the potential of meloxicam (MLX) developed as transferosomal gel as a novel lipidic drug delivery system to address osteoarthritis (OTA), a degenerative joint disease that causes pain and stiffness. By incorporating meloxicam into a transferosomal gel, our aim was to provide a targeted and efficient delivery system capable of alleviating symptoms and slowing down the progression of OTA., Material and Methods: Classical lipid film hydration technique was utilized to formulate different transferosomal formulations. Different transferosomal formulations were prepared by varying the molar ratio of phospholipon-90H (phosphodylcholine) to DSPE (50:50, 60:40, 70:30, 80:20, and 90:10) and per batch, 80mg of total lipid was used. The quality control parameters such as entrapment efficiency, particle size and morphology, polydispersity and surface electric charge, in vitro drug release, ex vivo permeation and stability were measured., Results: The optimized transferosomal formulations revealed a small vesicle size (121±12nm) and greater MLX entrapment (68.98±2.3%). Transferosomes mediated gel formulation MLX34 displayed pH (6.3±0.2), viscosity (6236±12.3 cps), spreadability (13.77±1.77 gm.cm/sec) and also displayed sustained release pattern of drug release (81.76±7.87% MLX released from Carbopol-934 gel matrix in 24h). MLX34 revealed close to substantial anti-inflammatory response, with ∼81% inhibition of TNF-α in 48h. Physical stability analysis concluded that refrigerator temperature was the preferred temperature to store transferosomal gel., Conclusion: MLX loaded transferosomes containing gel improved the skin penetration and therefore resulted into increased inhibition of TNF-α level., (Copyright © 2024 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.)

Objective: Lamotrigine (LTG) an anticonvulsant drug with a dissociation constant (pKa: 5.7), suffers from enhanced blood plasma spike after each dose, when administered as fast release tablet. Being BCS class-II candidate and pH dependent solubility, development of release-controlled tablets of LTG is a major challenge. This investigation aims at designing the release-controlled tablet (RCT) formulation of LTG using a solid dispersion (SD) technique via addressing its solubility and release problems., Material and Methods: RCT of LTG was fabricated using SD blend of Eudragit RL and Eudragit RS and PVP K-30 with different polymer blend ratio (1:5 and 1:7). The optimization of RCT of LTG was performed using D-optimal mixture design with three independent variables, three response variables, and one constraint. The dissolution rate was determined and data were then fitted to different mathematical models. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies and tableting parameters were analyzed., Result: In vitro studies of predicted optimized batches (POBs) have shown that drug release over a period of 12hours was 88.05±3.4% in media I, 86.10±3.7% in media II and 85.84±4.2% in media III. An in vitro kinetic model equating R 2 -value for all the tested models indicated that the first order and Higuchi release kinetics model were the most appropriate., Conclusion: Based on the optimized formulation consisting of SD of LTG with Eudragit RL, Eudragit RS and PVP K-30, the release rate was consistently similar throughout the GI tract, regardless of the pH of the environment., (Copyright © 2023 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.)

Objective: This investigation aimed to explore the potential of non-ionic surfactant based niosomal vesicles encapsulating tenoxicam (TN; anti-rheumatic drug) for the treatment of rheumatic diseases., Material and Methods: Mechanical dispersion technique with controlled pressure was employed to prepare different niosomal formulations. The effects of different ratios of surfactant (span-60), lipid, and sodium deoxycholate on noisome's physicochemical properties have been examined. Moreover, inhibition of TNF-α in lipopolysaccharide-activated cultured Human leukemia monocytic (THP-1) cells were demonstrated to assess the in vitro inflammation profile. Finally, the optimized niosomal formulation (TN3) was prepared in gel matrix consist of carbopol 934 (termed as TN34) and stability was also tested at 4±2 ̊C, 25±2 ̊C, 37±2 ̊C and 45±2 ̊C for 6 months., Results: The optimized niosomal formulation exhibited a small vesicle size (165±14nm) and high drug encapsulation (79.64±1.5%). Niosomal gel formulation TN34 showed pH (6.7), viscosity (6810±3.34 cps), spreadability (19.11±1.87gm.cm/sec) and also displayed sustained release pattern of drug release (98.16±0.07% TN released from gel matrix in 24h) in vitro release study. TN34 exhibited substantial anti-inflammatory response, with ∼75% inhibition of TNF-α in 48h. Stability investigation revealed that refrigerator temperature is most suitable for the storage of niosomal gel., Conclusion: Transdermal niosomal formulation displayed promising potential in the treatment of rheumatic diseases., (Copyright © 2023 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.)

Cinitapride has been widely given in gastro-esophageal reflux disease (GERD) and dysphagia due to irregularities of GI motilities. Mouth dissolving tablets were prepared for rapid availability and action of drug. Multipoint dissolution studies were conducted in 0.1 N HCl solution of pH 1.2 and phosphate buffer of pH 4.5 and 6.8. Drug release profile showed higher liberation of cinitapride at lower pH then basic medium (<80%). Formulation containing crospovidone (10%) was found to be optimized trial having excellent quality pharmaceutical attributes. The lowest AIC, highest MSC and regression (> 0.9) values were observed for Weibull kinetics in all dissolution medium reflecting the excellent model fitting for the present study. Accelerated stability testing data showed excellent results of drug assay (>99%) along with physical characteristics indicating the absence of drug degradation as well excipient interaction. The estimated shelf life period of various optimized trial formulations was found in between 33 to 41 months. [ABSTRACT FROM AUTHOR]

The implementation of the Chemical Weapons Convention (CWC) in 1997 was a milestone in the prohibition of chemical warfare agents (CWA). Yet, the repeated use of CWA underlines the ongoing threat to the population. Organophosphorus (OP) nerve agents still represent the most toxic CWA subgroup. Defensive research on nerve agents is mainly focused on the “classical five”, namely tabun, sarin, soman, cyclosarin and VX, although Schedule 1 of the CWC covers an unforeseeable number of homologues. Likewise, an uncounted number of OP pesticides have been produced in previous decades. Our aim was to determine the in vitro inhibition kinetics of selected organophosphono- and organophosphorothioates with human AChE, as well as hydrolysis of the agents in human plasma and reactivation of inhibited AChE, in order to derive potential structure–activity relationships. The investigation of the interactions of selected OP compounds belonging to schedule 1 (V-agents) and schedule 2 (amiton) of the CWC with human AChE revealed distinct structural effects of the P-alkyl, P-O-alkyl and N,N-dialkyl residues on the inhibitory potency of the agents. Irrespective of structural modifications, all tested V-agents presented as highly potent AChE inhibitors. The high stability of the tested agents in human plasma will most likely result in long-lasting poisoning in vivo, having relevant consequences for the treatment regimen. In conclusion, the results of this study emphasize the need to investigate the biological effects of nerve agent analogues in order to assess the efficacy of available medical countermeasures.

Background: Hydralazine hydrochloride (HZH) is a drug candidate used to treat pulmonary arterial hypertension. Extreme variability in oral dosing, bioavailability of 31%, variable half-life of 3 to 7 h and molecular weight of 196.6 Daltons, made the drug molecule suitable for transdermal system. Objective: The objective of the present investigation is to study the effect of penetration enhancers on release kinetics of hydralazine hydrochloride both in vitro and in vivo through reservoir based transdermal systems. Materials and Methods: Rate controlling membranes were formulated by using HPMC, Eudragit RLPO and Eudragit RSPO. Reservoir was formulated by using 16% poloxamer 407 gel by cold method as it is having sol-gel temperature at 37°C. Results and Discussion: The drug release followed zero order non-fickian super case-II diffusion transport mechanism. Enhancement ratio was more with IPM as penetration enhancer. Formulation F7 [ERLPO: HPMC 5:5 and IPM 15%] had maximum in vitro release of 95.68 ± 1.16% with flux value of 64.168±0.071 µg/h/cm², no significant difference in ex vivo permeation study was observed. The fabricated reservoir system was found to be safe for skin. In vivo kinetic studies projected a controlled release pattern with extended AUC of 25.760 ± 9.124 µg/mL/h with MRT 17.7 ± 0.37 h in transdermal route compared to oral route where AUC and MRT are 4.409 ± 2.015 µg/mL/h and 2.98 ± 1.24 h respectively. Conclusion: The drug reservoir transdermal system of HZH had varied in vitro release profile with varying the concentrations of penetration enhancer. The optimized transdermal system had extended AUC and MRT values compared to oral route and can enhance the bioavailability. [ABSTRACT FROM AUTHOR]

The objective of the present work was to review the availability and predictive value of non-animal toxicokinetic approaches and to evaluate their current use in European risk evaluations of food contaminants, additives and food contact materials, as well as pesticides and medicines. Results revealed little use of quantitative animal or human kinetic data in risk evaluations of food chemicals, compared with pesticides and medicines. Risk evaluations of medicines provided sufficient in vivo kinetic data from different species to evaluate the predictive value of animal kinetic data for humans. These data showed a relatively poor correlation between the in vivo bioavailability in rats and dogs versus that in humans. In contrast, in vitro (human) kinetic data have been demonstrated to provide adequate predictions of the fate of compounds in humans, using appropriate in vitro-in vivo scalers and by integration of in vitro kinetic data with in silico kinetic modelling. Even though in vitro kinetic data were found to be occasionally included within risk evaluations of food chemicals, particularly results from Caco-2 absorption experiments and in vitro data on gut-microbial conversions, only minor use of in vitro methods for metabolism and quantitative in vitro-in vivo extrapolation methods was identified. Yet, such quantitative predictions are essential in the development of alternatives to animal testing as well as to increase human relevance of toxicological risk evaluations. Future research should aim at further improving and validating quantitative alternative methods for kinetics, thereby increasing regulatory acceptance of non-animal kinetic data. [ABSTRACT FROM AUTHOR]

There is an ongoing debate about the benefit of fresh frozen plasma (FFP) infusion in organophosphorus (OP) pesticide-poisoned patients. This prompted us to investigate the kinetics of OP pesticide degradation by FFP with an enzymatic assay in vitro . Degradation was rapid with shortest half-lives of 19.5 s for chlorpyrifos-oxon, 6.3 min for paraoxon-ethyl and 17.9 min for dichlorvos. Heptenophos (78.0 min), mevinphos (101.8 min), profenofos (162.3 min) and malaoxon (179.7 min) showed half-lives of up to 3 h. Substantial longer degradation half-lives of 69.7–80.8 h were determined with chlorfenvinphos and bromfenvinphos. Methamidophos and omethoate showed no degradation by FFP indicated by half-lives similar to spontaneous hydrolysis. In conclusion, degradation by FFP depends on the particular OP pesticide and the used FFP batch. [ABSTRACT FROM AUTHOR]

Great efforts have been undertaken in the last decades to develop new oximes to reactivate acetylcholinesterase inhibited by organophosphorus compounds (OP). So far, a broad-spectrum oxime effective against structurally diverse OP is still missing, and alternative approaches, e.g. stoichiometric and catalytic scavengers, are under investigation. Fresh frozen plasma (FFP) has been used in human OP pesticide poisoning which prompted us to investigate the in vitro kinetics of OP nerve agent degradation by FFP. Degradation was rapid and calcium-dependent with the G-type nerve agents tabun, sarin, soman and cyclosarin with half-lives from 5 to 28 min. Substantially longer and calcium-independent degradation half-lives of 23-33 h were determined with the V-type nerve agents CVX, VR and VX. However, at all the tested conditions, the degradation of V-type nerve agents was several-fold faster than spontaneous hydrolysis. Albumin did not accelerate the degradation of nerve agents. In conclusion, the fast degradation of G-type nerve agents by FFP might be a promising tool, but would require transfusion shortly after poisoning. FFP does not seem to be suitable for detoxifying relevant agent concentrations in case of human poisoning by V-type nerve agents. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to study the in vitro replication of bovine herpesvirus types 1 and 5 (BoHV-1 and 5) at the beginning and end of the logarithmic growth phase of Madin-Darby Bovine Kidney (MDBK) cells. The replication kinetics and size of lysis and infection plaques of the field isolates 09/210 (BoHV-1) and 97/613 (BoHV-5) and the reference strains BoHV-1.1 Los Angeles 38 (LA38), BoHV-1.1 Cooper, BoHV-5a N569 and BoHV-5b A663 were evaluated. The highest mean virus titre was recorded for N569, followed by LA38 and 97/613. For most of the viruses, the virus titre values increased from 24h post-infection (hpi) up to 48hpi and then, they remained unchanged up to 72hpi. However, the virus titre for 09/210 was significantly lower and a slight, steady increase was observed from 24 to 72hpi. Furthermore, the largest lysis and infection plaques were recorded for 97/613 and LA38, respectively. According to this work, it is evident that there is a relationship between the replication of BoHV and the multiplication stage of MDBK cells. The results of this study contribute to the understanding of the replication behaviour in cell cultures of several strains of BoHV, which is critical for the rational design of in vitro experiments and vaccine production. [Copyright &y& Elsevier]

Intoxication by organophosphorous (OP) insecticides and nerve agents is often lethal and currently available therapeutics are often ineffective. A range of catalytic and stoichiometric OP scavengers have been investigated for use as potential treatments for OP poisoning. Recent studies have shown that one enzyme, OpdA, an enzyme involved in organophosphorous degradation, was an effective treatment for OP insecticide poisoning in animal models. Here we have tested OpdA for its ability to detoxify G- and V-type nerve agents in vitro. Although OpdA was found to have high catalytic activities for G-series toxins (soman and cyclosarin), it was substantially less active with V-type nerve agents. The activity towards V-series agents was close to the theoretical maximum for this enzyme (i.e. the rate determined by the chemistry of the leaving group); it seems unlikely that enzyme engineering or directed evolution could be used to improve upon this activity without a significant change in its reaction mechanism. [ABSTRACT FROM AUTHOR]

Abstract: The simultaneous use of the repellent DEET, pyridostigmine, and organophosphorus pesticides has been assumed as a potential cause for the Gulf War Illness and combinations have been tested in different animal models. However, human in vitro data on interactions of DEET with other compounds are scarce and provoked the present in vitro study scrutinizing the interactions of DEET, pyridostigmine and pesticides with human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBChE). DEET showed to be a weak and reversible inhibitor of hAChE and hBChE. The IC50 of DEET was calculated to be 21.7mM DEET for hAChE and 3.2mM DEET for hBChE. The determination of the inhibition kinetics of pyridostigmine, malaoxon and chlorpyrifos oxon with hAChE in the presence of 5mM DEET resulted in a moderate reduction of the inhibition rate constant k i. The decarbamoylation velocity of pyridostigmine-inhibited hAChE was not affected by DEET. In conclusion, the in vitro investigation of interactions between human cholinesterases, DEET, pyridostigmine, malaoxon and chlorpyrifos oxon showed a weak inhibition of hAChE and hBChE by DEET. The inhibitory potency of the tested cholinesterase inhibitors was not enhanced by DEET and it did not affect the regeneration velocity of pyridostigmine-inhibited AChE. Hence, this in vitro study does not give any evidence of a synergistic effect of the tested compounds on human cholinesterases. [Copyright &y& Elsevier]

Abstract: In this study, doxorubicin (DOX) was physically incorporated into pH-sensitive micelles made from a mixture of poly(l -histidine)-b-poly(ethylene glycol)/poly(l -lactide)-b-poly(ethylene glycol) (75/25, wt.%). The DOX-loaded mixed micelles were formulated using dialysis methods and optimal DOX incorporation was achieved at a drug/polymer feed ratio of 0.2 (wt./wt.) when a proper amount of aqueous phase (0.2, v./v.) was added into the common solvent (DMSO) solution, followed by dialysis at 4°C. Based on the results obtained from dynamic light scattering, UV–Vis absorption, and fluorescence experiments, it was demonstrated that the encapsulated drugs were mainly located inside the hydrophobic micelle cores, well protected and inaccessible to the exterior molecules. Under in vitro conditions, although the microstructure of the micelles was altered below pH 8.0 by the encapsulated drugs, the drug-loaded micelles still exhibited a desirable ability to control the drug release in response to tumor extracellular pH. [Copyright &y& Elsevier]

The Escherichia coli gene dnaQ coding for the ℇ subunit of DNA polymerase III was suppressed in vivo via antisense RNAs. To this aim, different fragments of dnaQ were cloned in reverse orientation into the pBAD-HisB vector or into pT3T7, and the corresponding antisense RNAs were conditionally expressed in vivo. Antisense transcripts featuring fast hybridization in vitro with dnaQ mRNA but lacking stability in vivo did not suppress the target gene. Moreover, the in vivo concentration of an antisense transcript was positively correlated to its silencing effectiveness. [ABSTRACT FROM AUTHOR]

Beta-chloroprene (2-chloro-1,3-butadiene, CD) is carcinogenic by inhalation exposure to B6C3F1 mice and Fischer F344 rats but not to Wistar rats or Syrian hamsters. The initial step in metabolism is oxidation, forming a stable epoxide (1-chloroethenyl)oxirane (1-CEO), a genotoxicant that might be involved in rodent tumorigenicity. This study investigated the species-dependent in vitro kinetics of CD oxidation and subsequent 1-CEO metabolism by microsomal epoxide hydrolase and cytosolic glutathione S-transferases in liver and lung, tissues that are prone to tumor induction. Estimates for Vmax and Km for cytochrome P450-dependent oxidation of CD in liver microsomes ranged from 0.068 to 0.29 μ;mol/h/mg protein and 0.53 to 1.33 μ;M, respectively. Oxidation (Vmax/Km) of CD in liver was slightly faster in the mouse and hamster than in rats or humans. In lung microsomes, Vmax/Km was much greater for mice compared with the other species. The Vmax and Km estimates for microsomal epoxide hydrolase activity toward 1-CEO ranged from 0.11 to 3.66 μ;mol/h/mg protein and 20.9 to 187.6 μ;M, respectively, across tissues and species. Hydrolysis (Vmax/Km) of 1-CEO in liver and lung microsomes was faster for the human and hamster than for rat or mouse. The Vmax/Km in liver was 3 to 11 times greater than in lung. 1-CEO formation from CD was measured in liver microsomes and was estimated to be 2–5% of the total CD oxidation. Glutathione S-transferase-mediated metabolism of 1-CEO in cytosolic tissue fractions was described as a pseudo-second order reaction; rates were 0.0016–0.0068/h/mg cytosolic protein in liver and 0.00056–0.0022 h/mg in lung. The observed differences in metabolism are relevant to understanding species differences in sensitivity to CD-induced liver and lung tumorigenicity. [ABSTRACT FROM AUTHOR]

In patients taking haloperidol (HP), circulating concentrations of reduced haloperidol (RHP increase disproportionately to the dose or concentration of the parent drug. In the current study, we tested the hypothesis that the nonlinearity is due to preferential saturation of the reoxidation of RHP to HP, and two factors that could amplify the nonlinearity - concentration-dependent binding of RHP by plasma proteins, or by red blood cells. In 25 patients with schizophrenia who were taking HP, the unbound fraction of HP (0.085±0.016) and RHP (0.244±0.026) in plasma, and the blood:plasma ratio for each compound were independent of their concentration. Thus, saturable binding of RHP to plasma proteins or red blood cells can be excluded. HP reductase and RHP oxidase activity were measured in human liver cytosol and microsomal fractions, respectively. Because ketone reductase-catalysed formation of RHP is stereospecific, we examined each enantiomer of RHP separately. The V for the oxidation of the S(−) and R(+) RHP enantiomers in four livers was 0.23±0.15 and 0.60±0.32 µmol/g protein per min (mean ± SD), respectively The K was 110±40 and 70±10 µM, respectively. In contrast, HP reductase activity displayed greater capacity and was not saturable. The rate of production of RHP at a HP concentration of 122 µM (the limit of HP solubility) in the same livers was 2.6±0.7 µmol/g protein per min. Despite the observed nonlinearity between the enzymatic pathways in vitro, RHP concentrations in vivo are 2-3 orders of magnitude lower than the K for oxidation of each enantiomer of RHP. Thus, it is unlikely that either saturable oxidation of RHP to HP, or saturable plasma protein or red cell binding account for the nonlinear relationship between steady state concentrations of RHP and HP in vivo. [ABSTRACT FROM AUTHOR]

The implementation of the Chemical Weapons Convention (CWC) in 1997 was a milestone in the prohibition of chemical warfare agents (CWA). Yet, the repeated use of CWA underlines the ongoing threat to the population. Organophosphorus (OP) nerve agents still represent the most toxic CWA subgroup. Defensive research on nerve agents is mainly focused on the "classical five", namely tabun, sarin, soman, cyclosarin and VX, although Schedule 1 of the CWC covers an unforeseeable number of homologues. Likewise, an uncounted number of OP pesticides have been produced in previous decades. Our aim was to determine the in vitro inhibition kinetics of selected organophosphono- and organophosphorothioates with human AChE, as well as hydrolysis of the agents in human plasma and reactivation of inhibited AChE, in order to derive potential structure–activity relationships. The investigation of the interactions of selected OP compounds belonging to schedule 1 (V-agents) and schedule 2 (amiton) of the CWC with human AChE revealed distinct structural effects of the P-alkyl, P-O-alkyl and N,N-dialkyl residues on the inhibitory potency of the agents. Irrespective of structural modifications, all tested V-agents presented as highly potent AChE inhibitors. The high stability of the tested agents in human plasma will most likely result in long-lasting poisoning in vivo, having relevant consequences for the treatment regimen. In conclusion, the results of this study emphasize the need to investigate the biological effects of nerve agent analogues in order to assess the efficacy of available medical countermeasures. [ABSTRACT FROM AUTHOR]