Camptothecin: solubility, in-vitro drug release, and effect on human red blood cells and sperm cold preservation.

BACKGROUND: Camptothecin (CPT) is an anticancer drug, and is not employed in the clinic because of its high hydrophobicity and low active form stability. CPT may also have potential for use in cold preservation. OBJECTIVE: To overcome these drawbacks, CPT solubility variations in the presence of cyclodextrins (CDs) and polyethylene glycol (PEG) were evaluated by Higuchi solubility experiments. MATERIALS AND METHODS: CPT was encapsulated in different cyclodextrins and polyethylene glycol using a co-evaporation method. The CPT interactions with CDs and PEG 6000 were investigated by Fourier-transformed infrared spectroscopy (FT-IR), and X-ray powder diffraction (XRPD). Then, CPT complexes were evaluated for in-vitro drug release. To evaluate the potential anticancer efficacy of the CPT complexes system, in-vitro cytotoxicity studies on human red blood cells were carried out using UV assay. The impact of the CPT complex systems on sperm motility protection during cold preservation at 4 degree C was studied using CASA. RESULTS: The dissolution profile of these preparations shows the improvement of the dissolution of the CPT following a fickien diffusion. The CPT solubility and stability improvement were the cause of the cytotoxicity on the red blood cells test. However, CPT alone, encapsulated, dispersed, and chemically modified protected spermatozoids during cold preservation. CONCLUSION: We confirm the interest in CPT encapsulated and dispersed in anticancer treatments. We also found that CPT encapsulated or dispersed could protect sperm against oxidative damage and improve the membrane integrity of human sperm. Consequently, CPT encapsulated our dispersed could eventually be beneficial for infertility therapy. Doi: 10.54680/fr23210110712.

Drug release, stability and efficiency of vitamin e loaded in liposomes for bovine sperm protection in cryopreservation medium.

BACKGROUND: It is known that a considerable number of drugs in clinical use or under development are water-insoluble drugs with poor bioavailability. The liposomal delivery system has drawn attention as one of the noteworthy approaches to increase both dissolution and absorption because of its biocompatibility and ability to encapsulate hydrophobic molecules in the lipid domain. However, several drawbacks have been reported, the most common is liposome structural instability. OBJECTIVE: To encapsulate alpha tocopherol into liposomes, to determine the new formulation stability and to study the drug-release of alpha tocopherol into the sperm cryopreservation medium. MATERIALS AND METHODS: The liposomes prepared by an ethanol injection method were characterized for size stability, alpha tocopherol release and sperm motility tests. RESULTS: The prepared unilamellar vesicles had both narrow size distribution (around 99 nm) and a good physical and chemical stability at 4°C during 12 months. The liposomes did not release the vitamin E immediately, but retained the protectant for 24 hours, probably due to the rigidity of the liposomal fence which was reinforced by adding cholesterol. Then, all vitamin E molecules were released by 48 hours. Release was potentially by Fickian diffusion probably by the creation of mini-ducts due to both agitation and fence hydration. Moreover, semen motility treated with vitamin E liposome preparations was significantly improved compared to all other treatments (including commonly used sperm conservation media). CONCLUSION: The stable vitamin E liposomes formulated in this work are a promising alternative for semen cryopreservation protection.

Encapsulation Nanotechnology in Sperm Cryopreservation: Systems Preparation Methods and Antioxidants Enhanced Delivery.

Sperm cryopreservation promotes the storage and transport of germplasm for its use in artificial insemination (AI) and other advanced reproductive technologies. However, sperm cryopreservation causes several stresses including thermal shock, osmotic damage, and ice crystal formation, thereby reducing sperm quality. Supplementing cryoprotectant media with antioxidants has been reported to be positive in different species. It has been widely suggested to combine antioxidants with nanotechnology, to maximize therapeutic activity and to minimize undesirable side effects. In this review, we discuss the role of different antioxidants in sperm cryopreservation and their improved therapeutic effect through their formulation using nanotechnology. In addition, we report the different nano-systems preparation methods present in literature. Whilst the use of nanotechnology in animal production is still in its infancy, encouraging results from nutrition, biocidal, remedial, and reproductive studies are driving further investigations.

Preparation and characterization of amorphous solid dispersions of nimesulide in cyclodextrin copolymers.

A study to enhance the dissolution rate of nimesulide (NIM), a poorly water-soluble, non-steroidal anti-inflammatory drug, was carried out through developing new amorphous solid dispersions (ASD) based on soluble or insoluble water cyclodextrin copolymers (alpha-cyclodextrin, beta-cyclodextrin and y-cyclodextrin polymers) synthesized by direct melt polycondensation. Amorphous solid dispersions of NIM in cyclodextrin copolymers, obtained by solvent evaporation, were characterized by thermogravimetric analyzer (TGA), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and fourier transform-infrared spectroscopy (FT-IR). These analyses provided the existence of interactions between amorphous drug and its carrier. A burst release of more than 80% NIM within approximately 70 minutes was seen with soluble alpha-cyclodextrin polymers (poly-alpha-sol) and insoluble gamma-cyclodextrin polymers (poly-gamma-insol) where no significant differences were observed with the other copolymers. Mathematical kinetic models such as zero order, Higuchi and Korsmeyer-Peppas were used to evaluate the kinetic and mechanism of release of NIM from the different ASD compared to lactose reference matrix. The kinetic of release of NIM from different ASD followed a Higuchi model and the mechanism of release was explained by Korsmeyer-Peppas model in which a fickian diffusion for lactose and soluble beta-cyclodextrin polymers (poly-beta-sol) was observed. However, an anomalous non-Fickian transport was found for the other copolymers.

Addressing differences in cancer: a framework for synergistic programming in cancer prevention and control.

Background: Cancer remains a leading cause of death worldwide and continues to disproportionately impact certain populations. Several frameworks have been developed that illustrate the multiple determinants of cancer. Expanding upon the work of others, we present an applied framework for cancer prevention and control designed to help clinicians, as well as public health practitioners and researchers, better address differences in cancer outcomes. Methods: The framework was developed by the Cancer Prevention and Control Research Network's Health Behaviors Workgroup. An initial framework draft was developed based on workgroup discussion, public health theory, and rapid literature review on the determinants of cancer. The framework was refined through interviews and focus groups with Federally Qualified Health Center providers (n=2) and cancer patients (n=2); participants were asked to provide feedback on the framework's causal pathways, completeness, and applicability to their work and personal life. Results: The framework provides an overview of the relationships between sociodemographic inequalities, social and structural determinants, and key risk factors associated with cancer diagnosis, survivorship, and cancer morbidity and mortality across the lifespan. The framework emphasizes how health-risk behaviors like cigarette smoking interact with psychological, psychosocial, biological, and psychosocial risk factors, as well as healthcare-related behavior and other chronic diseases. Importantly, the framework emphasizes addressing social and structural determinants that influence health behaviors to reduce the burden of cancer and improve health equity. Aligned with previous theory, our framework underscores the importance of addressing co-occurring risk factors and disease states, understanding the complex relationships between factors that influence cancer, and assessing how multiple forms of inequality or disadvantage intersect to increase cancer risk across the lifespan. Conclusions: This paper presents an applied framework for cancer prevention and control to address cancer differences. Because the framework highlights determinants and factors that influence cancer risk at multiple levels, it can be used to inform the development, implementation, and evaluation of interventions to address cancer morbidity and mortality.

Syndromic surveillance of acute gastroenteritis based on drug consumption.

Since 1998, the French Health Insurance (NHI) system had established a national database in order to reimburse drug prescriptions. These electronical data are a considerable potential source for syndromic surveillance because of their exhaustive and regular updates. The aim of this study was to develop a method to identify acute gastroenteritis (AG) cases from drug reimbursements of the NHI database. The algorithm aimed at discriminating AG from other pathologies was determined from a sample of 206 AG prescriptions and 351 non-AG prescriptions collected in five pharmacies. The AG case identification was mainly based on the lag time between the prescription and delivery day, the occurrence of non-AG case-specific drugs, AG case-specific drug associations and treatment duration. The discriminant algorithm led to a sensitive and specific indicator of medically treated cases of AG with a time-spatial resolution power which met the need for waterborne AG surveillance.

[About the improvement of urologic care for soldiers with erectile dysfunction].

Organizational concepts of improvement of urological aid given to military men with erectile dysfunction. The reasons for insufficiency of urological aid rendered to military men with erectile dysfunction were established. The algorithm of its diagnostics was developed. Complete and reduced volume of urological aid with reference to the existing medical and diagnostic capacities of military medical and preventive treatment facilities has been developed. Organizational concepts of improvement of urological aid given to the patients with erectile dysfunction have been determined.

Development, validation and method stability study of a LC-MS method to quantify leuprolide (Hormone analog) in human plasma.

A rapid, highly sensitive and simple high-performance liquid chromatographic-tandem mass spectrometric (LC-MS) assay is developed and validated for the quantification of leuprolide: a Gonadotropin Releasing Hormone analog (GnRH) in human plasma. Moreover, various parameters of the method stability are determined. After the addition of stable isotope (internal standard), the leuprolide was extracted from human plasma by a C18 solid phase micro extraction (MEPS) cartridge and directly injected into LC-MS/MS system. Chromatographic separation was achieved using a Waters Atlantis HILIC, C18, 150 × 2.1 mm, 5 µ column. Mobile phase was a mixture of acetate buffer (pH 3) and acetonitrile (25/75). Drug detection was performed by MS using electrospray ionization in positive mode. Multiple reaction monitoring (MRM) with a tandem mass spectrometer was used to detect the analytes. Precursor to product ion transitions of: m/z 605.5 â†’ m/z 110.2 and m/z 609.1 â†’ m/z 249.1 were used to quantify leuprolide and leuprolide-13C6-15N, respectively. Sample analysis time was 3 min for each injection. The assay exhibited a linear dynamic range of 0.0500-40 ng/ml for each analyte with a lower limit of quantification (LLOQ) of: 0.0500 ng/ml. Furthermore, a complete analytic validation was carried out, including tests on: The specificity, precision, accuracy, matrix effect and stability under different storage conditions. Importantly, the obtained results established: an acceptable precision and accuracy for concentration over standard curve range. Nevertheless, it is to emphasize the simplicity, rapidity and also the high precision and accuracy of this novel LC-MS method, offering useful information about solution stability. Finally, this work is a good alternative to quantify Leuprolide concentration in human blood, especially on human clinic trials step.

Increasing the throughput of label-free cell assays to study the activation of G-protein-coupled receptors by using a serial agonist exposure protocol.

Label-free, holistic assays, monitoring, for example, the impedance of cells on electrodes, are gaining increasing popularity in the evaluation of G-protein-coupled receptor (GPCR) ligands. It is the strength of these approaches to provide the integrated cellular response non-invasively, highly automated and with a device-dependent time resolution down to several milliseconds. With an increasing number of samples to be studied in parallel, the available time resolution is, however, reduced and the cost for the disposable sensor arrays may become limiting. Inspired by protocols from organ pharmacology, we investigated a simple serial agonist addition assay that circumvents these limitations in impedance-based cellular assays. Using a serial addition of increasing concentrations of a GPCR agonist while continuously monitoring the sample's impedance, we were able to establish a full concentration-response curve for the endogenous agonist histamine on a single layer of U-373 MG cells endogenously expressing the histamine 1 receptor (H1R). This approach is validated with respect to conventional, parallel agonist addition protocols and studies using H1R antagonists such as mepyramine. Applicability of the serial agonist addition assay was shown for other GPCRs known for their signaling via one of the canonical G-protein pathways, Gq, Gi/0 or Gs as well. The serial agonist addition protocol has the potential to further strengthen the output of label-free analysis of GPCR activation.

Asymmetry pays: visual lateralization improves discrimination success in pigeons.

Functional cerebral asymmetries, once thought to be exclusively human, are now accepted to be a widespread principle of brain organization in vertebrates [1]. The prevalence of lateralization makes it likely that it has some major advantage. Until now, however, conclusive evidence has been lacking. To analyze the relation between the extent of cerebral asymmetry and the degree of performance in visual foraging, we studied grain-grit discrimination success in pigeons, a species with a left hemisphere dominance for visual object processing [2,3]. The birds performed the task under left-eye, right-eye or binocular seeing conditions. In most animals, right-eye seeing was superior to left-eye seeing performance, and binocular performance was higher than each monocular level. The absolute difference between left- and right-eye levels was defined as a measure for the degree of visual asymmetry. Animals with higher asymmetries were more successful in discriminating grain from grit under binocular conditions. This shows that an increase in visual asymmetry enhances success in visually guided foraging. Possibly, asymmetries of the pigeon's visual system increase the computational speed of object recognition processes by concentrating them into one hemisphere while preventing the other side of the brain from initiating conflicting search sequences of its own.

Charcot's joint of the wrist in type 2 diabetes mellitus.

In patients with diabetes mellitus, Charcot's neuroarthropathy mainly affects major weight-bearing joints, especially the foot and ankle. Remarkably, we report a case of Charcot's joint of the wrist - an unusually rare localization in type 2 diabetic patient. A review of medical literature identified only three such cases so far.

NMR and ESR study of amphotericin B interactions with various binary phosphatidylcholine/phosphatidylglycerol membranes.

Several biologically relevant phospholipids are considered as potential excipients for IV administration liposome's formulation of AMB (Biopharmaceututics Classification System Class IV). On the basis of in vivo bioavaibility studies, DMPC and DMPG were ranked as the first potent encapsulation enhancers for this model drug, especially if one expects to target DMPG rich systems as pulmonary surfactant. Subsequently, dispersions (multilayers) of DMPC, DMPG or in binary systems with various molar ratios were prepared with or without AMB (molar ratios AMB/lipid) and further investigated using the 1H-,31P-NMR methods. It was found that equimolar preparations of DMPG/DMPG exhibited both a good encapsulation of AMB, while also probably able to target pulmonary surfactant. Besides DMPG did not exhibit the same solubilization properties. Conversely, no targeting by DMPC dispersion alone was expected, even if a good solubilization was obtained.

To what extent is it possible to dissociate the anxiolytic and sedative/hypnotic properties of GABAA receptors modulators?

The relatively common view indicates a possible dissociation between the anxiolytic and sedative/hypnotic properties of benzodiazepines (BZs). Indeed, GABAA receptor (GABAAR) subtypes have specific cerebral distribution in distinct neural circuits. Thus, GABAAR subtype-selective drugs may be expected to perform distinct functions. However, standard behavioral test assays provide limited direction towards highlighting new action mechanisms of ligands targeting GABAARs. Automated behavioral tests, lack sensitivity as some behavioral characteristics or subtle behavioral changes of drug effects or that are not considered in the overall analysis (Ohl et al., 2001) and observation-based analyses are not always performed. In addition, despite the use of genetically engineered mice, any possible dissociation between the anxiolytic and sedative properties of BZs remains controversial. Moreover, the involvement the different subtypes of GABAAR subtypes in the anxious behavior and the mechanism of action of anxiolytic agents remains unclear since there has been little success in the pharmacological investigations so far. This raises the question of the involvement of the different subunits in anxiolytic-like and/or sedative effects; and the actual implication of these subunits, particularly, α-subunits in the modulation of sedation and/or anxiety-related disorders. This present review was prompted by several conflicting studies on the degree of involvement of these subunits in anxiolytic-like and/or sedative effects. To this end, we explored the GABAergic system, particularly, the role of different subunits containing synaptic GABAARs. We report herein the targeting gene encoding the different subunits and their contribution in anxiolytic-like and/or sedative actions, as well as, the mechanism underlying tolerance to BZs.

5-HT2C receptors in psychiatric disorders: A review.

5-HT2Rs have a different genomic organization from other 5-HT2Rs. 5HT2CR undergoes post-transcriptional pre-mRNA editing generating diversity among RNA transcripts. Selective post-transcriptional editing could be involved in the pathophysiology of psychiatric disorders through impairment in G-protein interactions. Moreover, it may influence the therapeutic response to agents such as atypical antipsychotic drugs. Additionally, 5-HT2CR exhibits alternative splicing. Central serotonergic and dopaminergic systems interact to modulate normal and abnormal behaviors. Thus, 5HT2CR plays a crucial role in psychiatric disorders. 5HT2CR could be a relevant pharmacological target in the treatment of neuropsychiatric disorders. The development of drugs that specifically target 5-HT2C receptors will allow for better understanding of their involvement in the pathophysiology of psychiatric disorders including schizophrenia, anxiety, and depression. Among therapeutic means currently available, most drugs used to treat highly morbid psychiatric diseases interact at least partly with 5-HT2CRs. Pharmacologically, 5HT2CRs, have the ability to generate differentially distinct response signal transduction pathways depending on the type of 5HT2CR agonist. Although this receptor property has been clearly demonstrated, in vitro, the eventual beneficial impact of this property opens new perspectives in the development of agonists that could activate signal transduction pathways leading to better therapeutic efficiency with fewer adverse effects.

Mutant RecA proteins which form hexamer-sized oligomers.

We have analyzed the oligomeric properties of a number of mutant RecA proteins containing single amino acid substitutions within one region of the subunit interface. In contrast to wild-type RecA, which forms a heterogeneous population of different-sized oligomers, we find that many of these mutant proteins exist in a more homogeneous oligomeric form, which approximates to the size of a RecA hexamer. Some of these mutants have a significant level of activity in vivo for recombinational DNA repair and thus represent the first mutant RecA proteins identified which retain activity yet can exist in a discrete oligomeric state as free protein.

Nutritional status of patients hospitalised in Poland.

AIM: Screening and extended assessment of the nutritional status of patients on admission and on discharge from hospital were carried out. DESCRIPTION: The studies were carried out in four teaching hospitals, four provincial hospitals and four county hospitals in Poland. SUBJECTS: Screening examinations were carried out for 3310 randomly selected patients (every 10th patient admitted to hospital, including 1916 female cases aged from 16 to 92 y and 1394 male patients aged from 16 to 100 y). Extended examinations were carried out on 210 patients aged from 16 to 87 y (including 122 female and 88 male). MAIN ASSESSMENT PARAMETERS: Anthropometric (height, weight, body mass index (BMI), waist-to-hip ratio (WHR), arm circumference) and biochemical indices (erythrocyte count, haemoglobin concentration, white blood cell count, blood lymphocyte count and serum albumin serum concentration). The extended examinations included determination of antioxidant vitamins (A, C, E), vitamin B(12) and folic acid. RESULTS: On admission to hospital, 10.43% of the patients surveyed had a BMI below 20 kg/m(2), in 20.74% of patients serum albumin concentration was below 3.5 g/dl, indicating possible protein energy malnutrition. In addition, 21.02% had lymphocyte count below 1.5 x 10(3)/mm(3). During hospitalisation, deterioration in the nutritional status of the patient population occurred. On discharge from hospital, the percentage of patients with BMI < 20 kg/m(2) increased to 11.21% and the percentage with low blood albumin (<3.5 g/dl) increased to 28.57%. On admission, vitamin C deficiency was present in 51.8% of patients, folic acid deficiency in 32%, vitamin E deficiency in 10%, vitamin B(12) deficiency in 6.8% and vitamin A deficiency in 1.4%. Vitamin deficiencies were present equally in malnourished, overweight and obese patients. CONCLUSIONS: In patients admitted to hospitals in Poland, malnutrition risk demonstrated by BMI was observed in 10.43% of patients. On the basis of biochemical indices, increased nutritional risk was demonstrated in 21% of patients. Vitamin malnutrition was seen in the majority of patients. A significant correlation between weight, BMI, arm circumference, blood lymphocyte count and the number of days spent in hospital was observed. SPONSORSHIP: The Committee of Scientific Research and the Ministry of Health-PBZ 012-14.

Fast dissolving cyclodextrin complex of piroxicam in solid dispersion part I: influence of ß-CD and HPß-CD on the dissolution rate of piroxicam.

Sublingual drug delivery is an interesting route for drug having significant hepatic first-pass metabolism or requiring rapid pharmacological effect as for patients suffering from swallowing difficulties, nausea or vomiting. Sublingual absorption could however be limited by the kinetic of drug dissolution. This study evaluated influences of cyclodextrins (ß-CD or HP-ß-CD) and their different inclusion process (spray-drying or freeze-drying) on the drug dissolution kinetic of solid dispersions in poly(ethylene glycol) (PEG, Mw 6000Da) of piroxicam, used as poor hydrosoluble drug model. A secondary objective was to determine influences of drug dispersion process in PEG (evaporation or melting methods) on the drug dissolution kinetic of piroxicam. Piroxicam solid dispersions containing or not cyclodextrins were characterized by different scanning calorimetry (DSC), Thermogravometry analyser (TGA) and Fourier transform-infrared spectroscopy (FT-IR) spectroscopy. In vitro drug dissolution study of these solid dispersions was then performed. The results demonstrated the high potential and interest of solid dispersions of drug previously included in cyclodextrins for sublingual delivery of hydrophobic drugs. This study also showed the advantages of evaporation method on the melting ones during drug dispersion in PEG. Indeed, drug complexation with cyclodextrins as dispersion by melting prevented the presence in solid dispersions of drug in crystalline form which can represent up to 63%. Moreover, dispersion in PEG by evaporation method gave more porous drug delivery system than with melting methods. This allowed complete (limited at most at 80-90% with melting methods) and quick drug dissolution without rebound effect like with melting ones.

Evaluation of 8-oxodeoxyguanosine, typical oxidative DNA damage, in lymphocytes of ozone-treated arteriosclerotic patients.

In the present study we measured the amount of 8-oxo-2'-deoxyguanosine (8-oxo-dG) in DNA isolated from lymphocytes of arteriosclerotic patients undergoing ozonetherapy. Treatment of the patients with therapeutic concentration of ozone caused a significant increase over the control value in the amount of 8-oxo-dG of DNA isolated from their lymphocytes. However, only three out of six patients examined responded positively to the treatment in terms of the base damage. The increases varied among patients, and were in the range of 100-450%. This interindividual difference may at least be partly explained by recently demonstrated heritable susceptibility to ozone.

Stability assessment of ketoconazole in aqueous formulations.

Ketoconazole is an imidazole antifungal agent. It has a wide antifungal spectrum and possesses some antibacterial activity. In inappropriate formulations, especially in aqueous media, ketoconazole molecules may be unsteady. The stability of ketoconazole in aqueous media was assessed as a function of pH, antioxidant and ketoconazole concentrations. It was found that ketoconazole was least stable at pH 1 among the pH values studied (pH 1-9). Since the major degradation pathway was specific acid catalysis, based upon the transition-state theory, the entropy (DeltaS) of the activation was calculated and found to be negative indicating that the activated complex was more constrained than the individual species. The free energy of activation (DeltaG) was estimated to be 30 kcal mol(-1). The viscosity of the formulation was found to be more stable at high pH because carbopol is stable at basic pH and protected ketoconazole. It appears that the amount of ketoconazole in the formulation has a low influence on the degradation mechanisms. The increase of the butylated hydroxytoluene antioxidant levels from 0.05 to 0.4%, adversely affected the stability of ketoconazole. In conclusion, the expected shelf life of the final ketoconazole formulation (pH 7, 0.1% butylated hydroxytoluene) was 15 months.

Modifications of microsomal and nuclear fractions by butylated hydroxyanisole and its effect on benzo(a)pyrene metabolites binding to macromolecules.

The effect of butylated hydroxyanisole (BHA) administration on the hepatic components of the monooxygenase system and lipid peroxidation in microsomal and nuclear fractions was investigated in male Swiss mice. Addition of BHA to the diet for 8 days increased significantly the content of cytochrome P-450 (by 50%) and two times the specific activities of NADH- and NADPH-cytochrome c reductases in liver microsomes and lowered the concentration of cytochrome P-450 in liver nuclei. Lipid peroxidation of liver microsomes obtained from BHA fed mice was higher (by 70%) as compared with the control. The inhibition of peroxidation was shown when BHA was added to the incubation mixture containing control microsomal fraction or liver homogenate. When benzo(a)pyrene (BP) was incubated with liver microsomes from BHA fed mice the binding of BP metabolites to microsomal macromolecules increased 5.5-fold compared with control. However, there was no such effect in case of liver nuclei. In view of these results it has been postulated that BHA can play not only preventive role in chemical carcinogenesis.