生物分析与生物医学杂志

β-defensins are a family of antimicrobial molecules involved in inflammatory processes and infections. In human airways, β-defensin-2 (hβD-2) is the best characterized in bacterial and fungal infections; however, it has been insufficiently studied in viral infections. The respiratory syncytial virus (RSV) and adenoviruses (ADV) are important agents of acute respiratory infections. The aim of this study was to measure in vitro the production and antiviral activity of hβD-2 in HEp-2 cells and A549 cells infected with ADV and RSV; hβD-2 production at different times was assessed by RT-PCR, and its presence by immunodetection assay (Western blot) using antibodies anti-hβD-2. The effect of this defensin on viral replication was determined using recombinant hβD-2 in plaque assays. The results revealed that in the cell lines production of hβD-2is up regulated after ADV or RSV infection, in direct proportion to the exposure time to each virus. The use of a high concentration of recombinant hβD-2 resulted in less deleterious viral effect on the cells. The results suggest that both viruses induce hβD-2 production, no matter if the virus is enveloped or not, and that presence of hβD-2 reduces replication and cytopathic in vitro effect of RSV and ADV. The hβD-2 production by low pathogenicity viruses or live viral vaccines can be useful as therapeutic tools in some infectious diseases.

The differences in types of psychoses, the suboptimal therapeutic response of psychotic individuals to antipsychotics, the variation of the therapeutic effects of the same antipsychotic on different individuals with the same disease, resistance to treatment, relapses despite completing a course of antipsychotic treatment, and the broad spectrum of side-effects of antipsychotics including the most recently designed ones, are pivotal factors necessitating the discovery of new antipsychotic agents. These should be therapeutically potent, efficient in monotherapy and devoid of known dangerous adverse effects that antipsychotics are blamed for. In this comparative review we elucidate two antipsychotic drugs, namely haloperidol and clozapine (typical and atypical antipsychotic agents, respectively) and discuss both their advantages and disadvantages. Because the pathogenesis of psychoses is not yet fully understood, and the prevention of psychoses is almost impossible rather being a myth, the search for the so called ideal, or the near-ideal, antipsychotic agent will continue. Based on this we propose the design of a “hybrid structure” having the desired properties of haloperidol and clozapine, with the intention being to find an optimal antipsychotic agent that exerts efficient therapeutic effects against both positive and negative symptoms of psychosis causing least possible side effects, such as in monotherapy.

The current study deals with development and validation of a simple, fast and sensitive ultrafast liquid chromatographic method using the cardinal principles of analytical quality by design for estimation of paliperidone in extended release pharmaceutical dosage form. A Box-Behnken design was adopted for optimizing chromatographic conditions, especially the method robustness by selecting organic phase composition, mobile phase flow rate and strength of tetra butyl ammonium hydrogen sulfate solution as the factors, and evaluating their effect on the responses like, retention time and tailing factor. The chromatography was performed on a C-18 column (250 × 4.6 mm, 5 μm) using methanol: 10 mM tetra butyl ammonium hydrogen sulfate (95:5% v/v) as mobile phase at flow rate of 1.0 ml/min with photodiode array detection at 279 nm. Method validation studies revealed calibration curve with linearity of drug concentration ranging between 2 and 100 μg/ml. Values of accuracy were found to be well within the acceptance limit with mean percent recovery between 98.22 and 102.96%. Inter and intra-day precision showed percent RSD values were within the acceptance limits. Method sensitivity revealed that limit of detection and limit of quantitation as 0.5 μg/ml and 2 μg/ml, respectively. The system suitability analysis also yielded high degree of method robustness. Overall, the UFLC method was found suitable for determination of paliperidone in bulk and pharmaceutical dosage forms.

The use of probiotics as preventive agents in colorectal cancer (CRC), as widely suggested in many clinical and pre-clinical studies, was often linked to the potency of short chain fatty acids (SCFAs) in the gut. However, there remains an incomplete understanding of the fatty-acid-producing activity of certain probiotics and their cancer preventive potential. In the current study, L. fermentum strains were investigated for their potential use with CRC treatments. Using cell-free extracts, L. fermentum NCIMB -5221, - 2797, and -8829 were first compared based on their SCFAs production and anti-proliferative activity against Caco-2 colon cancer cells. The corresponding SCFAs synthetic formulations, similar to the ones produced by the bacteria, were prepared and compared with the latter to determine the role and efficacy of naturally produced SCFAs in inhibiting the proliferation of colon cancer cells. Subsequently, the bioactivity and stability of L. fermentum bacterial strains in a simulated intestinal fluid (SIF) was determined. Results showed that L. fermentum NCIMB -5221 and -8829 were the most potent in producing SCFAs, in particular, acetic (192.3 ± 4 mg/L minimum), propionic (69.2 ± 1.6 mg/L minimum), and butyric (35.4 ± 2.9 mg/L minimum) acids. They were also found to inhibit the growth of Caco-2 cells (53.4 ± 1.6%, 72 h, p = 0.021) in comparison with L. acidophilus ATCC 314. Additionally, they showed resistance to SIF (16.3 ± 1.9% minimum, 72 h, p = 0.006) and produced SCFAs in SIF at concentrations high enough to significantly inhibit Caco-2 proliferation (74.73 ± 2.1%, 72 h). Based on characteristics related to bacterial cell survival, SCFA production, and anti-proliferative activity, L. fermentum NCIMB -5221 and - 2797 could potentially be considered as biotherapeutic agents against CRC.