Characterization of cell-free circulating DNA in plasma in patients with prostate cancer

Cell-free circulating DNA in plasma and serum may serve as a biomarker for malignant tumor detection and follow up in patients with a variety of solid tumors including prostate cancer. In healthy patients, DNA is normally released from an apoptotic source which generates small fragments of cell-free DNA, whereas cancer patients have cell-free circulating DNA that originated from necrosis, autophagy, or mitotic catastrophe. Cell-free circulating DNA levels were measured by a quantitative real-time PCR method with a set of primers targeted to amplify the consensus ALU apoptotic versus necrotic origin. Prostate cancer patients before and 3 months after diagnosis showed cell-free circulating DNA released at apoptotic and non-apoptotic cell death. Interestingly, all patients after 6 months demonstrated DNA released at non-apoptotic cell. The principal source of cell-free circulating DNA is of apoptotic and non-apoptotic cell death. However, during treatment, this feature could change. Therefore, the study of cell-free circulating DNA would be important to follow the evolution of the disease during the treatment.     

Assessment of fungal viability after long-wave ultraviolet light irradiation combined with riboflavin administration

Background

Corneal collagen cross-linking (CXL), a technique that combines riboflavin administration with long-wave ultraviolet light irradiation, was primarily developed to increase the biomechanical strength of collagen fibrils of the cornea to avoid the progression of keratoconus. Recently, this method has been proposed to treat selected cases of infectious keratitis.

Methods

To test the protocol used for progressive keratoconus in infectious keratitis, Candida albicans, and Fusarium solani, strains were exposed to irradiation using a wavelength of 365 nm at a power density of 3 mW/cm² for 30 min in the presence of riboflavin photosensitizer. All experiments were performed in triplicate. Qualitative and quantitative measurements of fungal viability used plate cultures and an automated trypan blue dye exclusion method respectively. Fungal cell diameter was also assessed in all groups. Statistical analyses were performed using the triplicate values of each experimental condition.

Results

Experimental findings of photodynamic therapy applied to the cell inactivation of both yeasts and filamentous fungi were compared with control groups. Qualitative results were corroborated with quantitative findings which showed no statistical significance between challenged samples (experimental groups) and the control group (p-value?=?1). In comparison with a control group of live cells, statistical significance was observed when riboflavin solution alone had an effect on the morphologic size of filamentous fungi, while ultraviolet light irradiation alone showed a slight decrease in the cell structure of C. albicans.

Conclusions

The impact of long-wave ultraviolet combined with riboflavin photosensitizer showed no antifungal effect on C. albicans and F. solani. The significant decrease in cell morphology of both filamentous fungi and yeasts submitted to photosensitizing riboflavin and exposure to ultraviolet light, respectively, may be promising in the development and standardization of alternatives for fungal cell inactivation, because of their minimal cytotoxic effects on the corneal surface. The methodological improvement in the preparation and application of individual chemical compounds, such as riboflavin, or physical systems, such as a long-wave light source, as antifungal agents may also assist in establishing promising therapeutic procedures for keratomycosis.     

Effect of conjugated linoleic acid (CLA) on lipid profile and liver histology in laboratory rats fed high-fructose diet

The objective of the study was to assess the effect of CLA on serum lipid profile, plasma malondialdehyde and liver histology in Wistar rats fed high-fructose diet. Eighteen rats were randomly assigned to three experimental groups and fed for the next 21 days. The experimental diets were: I, Control; II, Fructose (63.2% of fructose); and III, CLA+Fructose (1% CLA and 63.2% of fructose). The experimental treatments had no effect on body weight of the rats. The LDL+VLDL cholesterol, TG and liver weight were significantly increased in animals fed Fructose. MDA concentrations were significantly increased in rats fed Fructose diet but CLA+Fructose diet had no effect on this marker. In the same line, the histological examination of the livers showed a series of morphological alterations, notably hepatic steatosis in animals fed high-fructose diet. No signs of the steatosis in rats fed CLA+Fructose diet were observed. In conclusion, CLA in high-fructose diet, decreases serum LDL+VLDL and TG and plasma MDA concentrations as well as liver weight and liver cholesterol, thus opposing the effects of high-fructose diet and showing a potential antiatherogenic effect. Similarly, dietary CLA fed at 1% level (w/w) in high-fructose diet, prevented steatosis observed histologically in livers of rats fed high-fructose diets.     

Comparison of the cytotoxic effect of lapachol, α-lapachone and pentacyclic 1,4-naphthoquinones on human leukemic cells

The pentacyclic 1,4-naphthoquinones 1a–d were cytotoxic (IC₅₀ ∼ 2–7 μM) to human leukemic cell lines K562 (oxidative stress-resistant), Lucena-1 (MDR phenotype) and Daudi. Fresh leukemic cells obtained from patients, some with the MDR phenotype, were also sensitive to these compounds. The pentacyclic 1,4-naphthoquinones 1a and 1c induced apoptotic cell death in cells from leukemic patients as determined by flow cytometry. Conversely, the cell lines were highly insensitive to lapachol (2) and α-lapachone (3). Mitomycin-C inhibited cell proliferation at concentrations as low as 0.5 μM. The low toxicity against lymphocytes activated by phytohemagglutinin shows that these compounds are selective for the cancer cells studied. Previous data suggest that these compounds (1a–d) can be bioactivated in situ by reduction followed by rearrangement leading to enones, which are powerful alkylating agents. In contrast, lapachol (2) and β-lapachone (3), which cannot be bioactivated by reduction, showed little activity against the same cell lines.     

Design,Synthesis and Pharmacological Characterization of Endomorphin Analogues with Non‐Cyclic Amino Acid Residues in Position 2

Abstract: A series of endomorphin‐1 (EM‐1) and endomorphin‐2 (EM‐2) analogues, containing non‐cyclic amino acids (Ala, d ‐Ala, β‐Ala, NMeAla, d ‐NMeAla or Sar) instead of Pro in position 2 was synthesized, where NMeAla = N‐methylalanine and Sar = N‐methylglycine, sarcosine. The opioid activity profiles of these peptides were determined in μ and δ opioid receptor (MOR and DOR)‐representative binding assays and bioassays in vitro, as well as in the mouse hot‐plate test in vivo. Finally, the degradation rates of all analogues in the presence of either rat brain homogenate or selected proteolytic enzymes were determined. Analogues of EM‐2 were generally more potent than the respective analogues of EM‐1. EM‐2 analogues with d ‐Ala or d ‐NMeAla were about twofold more potent than the parent peptide and were least prone to degradation by brain homogenate, dipeptydyl peptidase IV and aminopeptidase M. In the in vivo test, [d ‐Ala²]EM‐2 and [d ‐NMeAla²]EM‐2 showed much higher analgesic potency than EM‐2 which confirmed the usefulness of structural modifications in obtaining new leads for pain‐relief therapeutics.     

Antioxidative action of methanolic extract and buthanolic fraction of Vochysia tucanorum Mart. in the gastroprotection

Aim of the study

Vochysia tucanorum is an important medicinal plant used in the Cerrado of Brazil against gastric disorders and this study reveals the pharmacological action of this traditional medicine use.

Materials and methods

The methanolic extract (E-MeOH) and buthanolic fraction (Fr-Bu) obtained from V. tucanorum were challenged by different necrotizing agents in rodents. NO-synthase inhibitor (L-NAME) and SH blocker (NEM) were used to evaluate the participation of cytoprotective factors in E-MeOH and Fr-Bu gastroprotection. Antiulcerogenic action of V. tucanorum was evaluated in rats and mice at doses 250, 500 or 1000 mg/kg (E-MeOH) and 37.5, 75 or 150 mg/kg (Fr-Bu).

Results

Both E-MeOH and Fr-Bu present elevated gastroprotective action in all in vivo experimental models, without signs of acute toxicity. The mechanisms involved in the gastroprotective action of E-MeOH and Fr-Bu are related to the antioxidant activity and protection to gastric mucosa NO levels. Phytochemical investigations of Fr-Bu identified different pentacyclic triterpenoids such as betulinic acid, erythrodiol, epi-betulinic acid and mixtures of ursolic acid and oleanolic acid derivatives as the major constituents. The presence of such triterpenoids in Fr-Bu is probably related to the potent gastroprotective action of this medicinal plant species.

Conclusion

Effectiveness in gastroprotection and the absence of acute toxicity indicate this species as a promising herbal drug that is in accordance with ethnopharmacological use against gastric disorders.