Optimization of high pressure homogenization in the production of liposomal dispersions

Liposomes are spherical, biodegradable, and biocompatible vesicular systems. These vesicles are built from phospholipid double layers (membranes) surrounding the inner water phase. Liposomes are highly desirable as drug carriers because they can incorporate hydrophilic, hydrophobic and amphipathic drug substances (drugs). The physicochemical properties of liposomes such as size, charge, surface properties and encapsulation efficiency can highly influence their in vivo stability and kinetics. The aim of our study was to prepare liposomal dispersions and to determine the influence of cycles of high pres-sure homogenization on some parameters, such as vesicle size and polydispersity index (PDI). Higher homogeni-zation pressures and repeated recirculation led to further reduction in vesicle diameter and heterogeneity. For preparing liposomal dispersions Phosal IP 40 and Phosal 75 SA were used (Lipoid, Germany). Liposomal dispersions were prepared according to the thin film hydration method. By sampling after each cycle, an estimate was made of how many cycles are needed for the dispersion to have satisfactory parameters (size and PDI). The size and PDI analysis of the liposomes were carried out by using Zetasizer (Nano series) ZS 90, Malvern Instruments. High-pressure homogenization was carried out in 10 cycles and based on the obtained liposome size values and PDI, was determined how many cycles are needed in the process of homogenization. With each cycle, the size of the liposomes decreased and PDI value was reduced. It has been observed that after 5 cycles of homogenization there is no significant decrease in the size of the liposomes and PDI. Therefore, in the further production of liposomes with active substances with these raw materials, is recommended to use only 5 cycles of homogenization

Fluorimetric profiles, flavonoid and polyphenols content of acacia, meadow and honeydew honey samples and their correlation with colour intensity of honey

Introduction: Previous studies have showed that fluorimetric analysis may be used as a simple, rapid, low cost and reliable method for authentication botanical origin of honey. Primary aims of this study were to record fluo-rescence spactra of acacia, meadow and honeydew honey samples and to determine content of flavonoid and pol-yphenoles in relation to colour intensity of honey. Material and methods: Fluorescence spectra of honey samples were recorded. Spectrophotometric analysis was used to determine flavonoid and polyphenols content. The honey color scoring was developed by the authors as the arbitrary system. Results: Acacia honey showed high fluorescence emission intensity after an excitation at 340 nm, 390 nm and 440 nm. Meadow honey showed fluorescence after excitation at 390 nm and 440 nm, while fluorescence, caused by ex-citation at 340 nm, was absent. Honeydew honey showed low intensity of fluorescence at 440 nm excitation while fluorescence was absent at 340 nm and 390 nm excitation, respectively. Statistically significant difference was found for flavonoids and polyphenols levels, between honeydew and acacia honey. Statistically significant differ-ence in polyphenols levels between meadow and acacia honey was found. There was no statistically significant dif-ference of flavonoids and polyphenols between samples of meadow and honeydew honey. Conclusion: Fluorimetric profiles, flavonoid and polyphenols content, together with colour intensity of honey may be useful in authenitication of botanical origin of honey

Effects of botulinum toxin type A facial injection on monoamines and their metabolites in sensory, limbic and motor brain regions in rats

Despite its toxicity, botulinum neurotoxin type A (BTX-A) is a valuable therapeutic agent for several motor, autonomic and pain disorders. Numerous studies have described its peripheral as well as central effects. Using reversed-phase High Performance Liquid Chromatography with Electrochemical Detection (HPLC-ED) and gradient elution, we quantified the concentrations of dopamine (DA), noradrenaline (NA), serotonin (5-HT) and their metabolites in 10 brain regions, ipsilateral and contralateral from the site of unilateral BTX-A administration (5 U/kg) into the rat whisker pad. In regions associated with nociception and pain processing we also examined possible BTX-A effects in combination with formalin-induced inflammatory orofacial pain. The dominant BTX-A effects on the monoamines and their metabolites were insignificant. The only significant increase caused by BTX-A alone was that of NA in striatum and serotonin in hypothalamus. While antinociceptive effects of BTX-A are most probably not related to central monoamine concentrations, the localized increased NA and 5-HT concentrations might play a role in reported BTX-A efficacy for the treatment of depression

Hyperhomocysteinemia and Its Treatment in Patients with Ischemic Stroke

Homocistein je metabolit nastao u procesu demetilacije metionina. Ima proaterogeno, protrombotsko, prooksidativno, proapoptotsko, neurotoksično, neuroinflamatorno i neurodegenerativno djelovanje. Hiperhomocisteinemija je povezana s postojanjem mutacije C667T MTHFR, sniženjem razine folne kiseline i vitamina B-grupe, ali i s dugotrajnim uzimanjem nekih lijekova. Provedeno je istraživanje u Klinici za neurologiju Univerzitetskoga kliničkog centra u Tuzli. Mjerene su razine homocisteina u šezdeset ispitanika obaju spolova u akutnoj fazi ishemijskog cerebrovaskularnog inzulta, a potom su praćeni efekti medikamentnog pristupa (folna kiselina, vitamini B-grupe) šestomjesečno u sljedeće tri godine. Hiperhomocisteinemija je bila prisutna u 16,67% bolesnika, a prosječna razina bila je viša u pacijenata muškog spola (p=0,073). Svaki treći oboljeli muškarac (33,3%) imao je povišene razine (p < 0,001), dok u bolesnica nije uočena hiperhomocisteinemija. Prilikom unosa folne kiseline u dnevnoj dozi od 5 mg peroralnim putem razine homocisteina bile su normalizirane u svih, ali su nekima dodatno ordinirani i vitamini B-grupe.Homocysteine is a metabolite of methionine demethylation. It has proatherogenic, prothrombotic, prooxidative, proapoptotic, neurotoxic, neuroinflammatory and neurodegenerative effects. Hyperhomocysteinemia correlates with C667T MTHFR mutation, decreased folic acid and vitamin B levels, and prolonged use of certain medications. We measured homocysteine levels in sixty patients at the Department of Neurology of the University Clinical Centre Tuzla and monitored the effects of medicaments (folic acid, vitamin B) every six months over a three-year period. In acute phase of ischemic stroke, hyperhomocysteinemia was present in 16.67% of patients. The average level was higher in male patients (p=0.073). Higher than normal homocysteine levels were recorded in every third male patient (33.3%) (p<0.001). Hyperhomocysteinemia was not observed in women with ischemic stroke. The oral administration of 5 mg folic acid per day normalized homocysteine levels in all patients, but some also received vitamin B

Hyperhomocysteinemia and Its Treatment in Patients with Ischemic Stroke

Homocistein je metabolit nastao u procesu demetilacije metionina. Ima proaterogeno, protrombotsko, prooksidativno, proapoptotsko, neurotoksično, neuroinflamatorno i neurodegenerativno djelovanje. Hiperhomocisteinemija je povezana s postojanjem mutacije C667T MTHFR, sniženjem razine folne kiseline i vitamina B-grupe, ali i s dugotrajnim uzimanjem nekih lijekova. Provedeno je istraživanje u Klinici za neurologiju Univerzitetskoga kliničkog centra u Tuzli. Mjerene su razine homocisteina u šezdeset ispitanika obaju spolova u akutnoj fazi ishemijskog cerebrovaskularnog inzulta, a potom su praćeni efekti medikamentnog pristupa (folna kiselina, vitamini B-grupe) šestomjesečno u sljedeće tri godine. Hiperhomocisteinemija je bila prisutna u 16,67% bolesnika, a prosječna razina bila je viša u pacijenata muškog spola (p=0,073). Svaki treći oboljeli muškarac (33,3%) imao je povišene razine (p < 0,001), dok u bolesnica nije uočena hiperhomocisteinemija. Prilikom unosa folne kiseline u dnevnoj dozi od 5 mg peroralnim putem razine homocisteina bile su normalizirane u svih, ali su nekima dodatno ordinirani i vitamini B-grupe.Homocysteine is a metabolite of methionine demethylation. It has proatherogenic, prothrombotic, prooxidative, proapoptotic, neurotoxic, neuroinflammatory and neurodegenerative effects. Hyperhomocysteinemia correlates with C667T MTHFR mutation, decreased folic acid and vitamin B levels, and prolonged use of certain medications. We measured homocysteine levels in sixty patients at the Department of Neurology of the University Clinical Centre Tuzla and monitored the effects of medicaments (folic acid, vitamin B) every six months over a three-year period. In acute phase of ischemic stroke, hyperhomocysteinemia was present in 16.67% of patients. The average level was higher in male patients (p=0.073). Higher than normal homocysteine levels were recorded in every third male patient (33.3%) (p<0.001). Hyperhomocysteinemia was not observed in women with ischemic stroke. The oral administration of 5 mg folic acid per day normalized homocysteine levels in all patients, but some also received vitamin B

Serum levels of oxidative stress marker malondialdehyde in breast cancer patients in relation to pathohistological factors, estrogen receptors, menopausal status, and age

Introduction: The aim of this study was to determine the serum levels of malondialdehyde (MDA) in patients with invasive breast cancer in relation to its serum levels in patients with benign breast disease, and to investigate correlation between MDA serum levels with pathohistological prognostic factors (tumor size, lymph node involvement, and histologic grade [HG]), estrogen receptor (ER) status, and with breast cancer patient’s age and menopausal status. Methods: A total of 43 with well-documented invasive breast cancer were included in this study: 27 with positive axillary’s lymph nodes, and 16 with negative axillary’s lymph nodes, and 39 patients with findings of benign breast diseases. MDA determination in serum of breast cancer and benign breast disease patients was performed by the fluorimetric method, immunohistochemical staining was performed for ER, and routine pathohistological examination was conducted for pathohistological factors. Results: MDA serum levels in breast cancer patients were significantly higher than MDA serum levels in benign breast disease patients (p = 0.042). No statistically significant difference between MDA serum levels in breast cancer patients with and without lymph node metastases was found (p = 0.238). No statistically significant correlations between MDA serum levels and tumor size (p = 0.256), HG (p = 0.124), or number of positive lymph nodes (0.113) were found. A statistically significant correlation between serum MDA levels and ages of breast cancer patients with lymph node metastases was found (p = 0.006). Conclusion: Obtained results support the importance of MDA in the carcinogenesis of breast cancer. According to our findings, serum level of MDA could not be a useful prognostic factor in breast cancer

Comparative study of long-term effects of atorvastatin and rosuvastatin on fasting glucose and hemoglobin A1c in patients with cardiovascular diseases

Introduction: Statins are lipid lowering medications, used for the prevention of cardiovascular diseases (CVD), but have shown to increase the risk of Type 2 diabetes mellitus. The aim of this study was to investigate the effects of high-potency statins, atorvastatin, and rosuvastatin on fasting glucose (FG) and hemoglobin A1c (HbA1c) in CVD patients. Methods: The case–control study included 123 patients from Tuzla Canton, Bosnia, and Herzegovina, with a diagnosis of CVD, treated in three health centers: Public Health Center Gračanica, Banovići, and Čelić. Of total patients, 84 were statin users (39 atorvastatin users and 45 rosuvastatin users) and 39 were not. Demographic data, diagnosis, and data of the therapy were taken from the medical records, as well as data of the FG and HbA1c, measured before or within 3 months of the statin therapy introduction. For the same patients, FG and HbA1c were also measured at least 3 months after the introduction of therapy. Results: Obtained results have shown a significant increase of FG in CVD patients on statin therapy in relation to control (p = 0.034). Comparing the diabetogenic effects of atrovastatin and rosuvastatin, it was found that the HbA1c in patients on atorvastatin therapy was significantly higher comparing to those on rosuvastatain therapy (p = 0.028). The FG was significantly increased (p = 0.027) after atrovastatin therapy. Similar results were obtained in diabetogenic CVD patients, where HbA1c on atorvastatin therapy was significantly higher comparing to HbA1c in those on rosuvastatain therapy (p = 0.039). A significant correlation was found between the increase in FG and HbA1c with the duration of atorvastatin therapy (p = 0.001 and p = 0.033), and between the increase in HbA1c and the duration of rosuvastatin therapy (p = 0.001). Conclusion: Long-term therapy with high-potency statins, atorvastatin, and rosuvastatin, may increase levels of FG and HbA1c in patients with CVD, where atorvastatin shows more significant effects

Clinical and Demographic Determinants of Cognitive Disorders in Multiple Sclerosis Patients

Multiple sclerosis (MS) is a chronic, inflammatory, (auto) immune disease of the central nervous system (CNS). The aim of the study was to determine the distribution of cognitive disorders in MS in relation to demographic parameters, degree of clinical disability and depression. The prospective study included 135 subjects with MS in the Clinic of Neurology of the University Clinical Center in Tuzla. The first group consisted of women (101 respondents) and the second of men (34 respondents). Clinical assessment instruments were: Expanded Disability Status Scale Score, Mini Mental Status, Beck Depression Scale, Battery of Cognitive Function Assessment Tests: Wechsler Intelligence Scale, Revised Beta Test, Raven Coloured Progressive Matrix, Wechsler Memory Verification Scale, Audio Memory Test learning, Rey-Osterriecht complex character test, verbal fluency test. There were no significant differences between the mentioned groups in age, level of education, duration of the disease, severity of disease symptoms or in the prevalence of certain forms of MS. Cognitive disorders are present in 40-60 % of subjects with MS. Visuospatial, visuoconstructive, visuoperceptive functions, mnestic functions were most affected in both groups of respondents. There was no difference in the level of depression in relation to sex. Poor results of cognitive parameters in 32.7 % can be considered the cause of high scores of EDSS in female patients and in 29.2 % in patients, which is not statistically significant. The correlation between depression and EDSS is positive but not statistically significant in both sexes. Cognitive disorders are heterogeneous regardless of sex. Cognitive impairment in MS patients is related to impairment of working ability and memory, executive functions and attention. Subjects with a more severe degree of clinical disability had poorer cognitive functions