Structure based virtual screening of ligands to identify cysteinyl leukotriene receptor 1 antagonist

Montelukast and Zafirlukast are known leukotriene receptor antagonists prescribed in asthma treatment. However, these fall short as mono therapy and are frequently used in combination with inhaled glucocorticosteroids with or without long acting beta 2 agonists. Therefore, it is of interest to apply ligand and structure based virtual screening strategies to identify compounds akin to lead compounds Montelukast and Zafirlukast. Hence, compounds with structures having 95% similarity to these compounds were retrieved from NCBI׳s PubChem database. Compounds similar to lead were grouped and docked at the antagonist binding site of cysteinyl leukotriene receptor 1. This exercise identified compounds UNII 70RV86E50Q (Pub Cid 71587778) and Sure CN 9587085 (Pub Cid 19793614) with higher predicted binding compared to Montelukast and Zafirlukast. It is shown that the compound Sure CN 9587085 showed appreciable ligand receptor interaction compared to UNII 70RV86E50Q. Thus, the compound Sure CN 9587085 is selected as a potent antagonist to cysteinyl leukotriene receptor 1 for further consideration in vitro and in vivo validation.     

An overview of malaria transmission from the perspective of Amazon Anopheles vectors

In the Americas, areas with a high risk of malaria transmission are mainly located in the Amazon Forest, which extends across nine countries. One keystone step to understanding the Plasmodium life cycle in Anopheles species from the Amazon Region is to obtain experimentally infected mosquito vectors. Several attempts to colonise Ano- pheles species have been conducted, but with only short-lived success or no success at all. In this review, we review the literature on malaria transmission from the perspective of its Amazon vectors. Currently, it is possible to develop experimental Plasmodium vivax infection of the colonised and field-captured vectors in laboratories located close to Amazonian endemic areas. We are also reviewing studies related to the immune response to P. vivax infection of Anopheles aquasalis, a coastal mosquito species. Finally, we discuss the importance of the modulation of Plasmodium infection by the vector microbiota and also consider the anopheline genomes. The establishment of experimental mosquito infections with Plasmodium falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide interesting models for studying malaria in the Amazonian scenario is important. Understanding the molecular mechanisms involved in the development of the parasites in New World vectors is crucial in order to better determine the interaction process and vectorial competence.     

Protein glycosylation in the spores of the microsporidia Paranosema (Antonospora) grylli

Long adaptation of microsporidia, a large group of fungi-related protozoa, to intracellular lifestyle has resulted in drastic minimization of a parasite cell. Thus, diversity of carbohydrates in microsporidia glycoproteins and proteoglycans is expected to be restricted by O-linked manno-oligosaccharides because three genes involved in O-mannosylation of proteins and no components of N-linked glycosylation machinery were found in genome of human pathogen Encephalitozoon cuniculi. In this study we investigated glycosylation of spore proteins of microsporidia Paranosema (Antonospora) grylli infecting crickets Gryllus bimaculatus. Using periodic acid-Shiff reagent staining we have demonstrated that some P. grylli spore proteins are highly-glycosylated. The major polar tube protein (PTP1) of 56 kDa was shown as the most intensively decorated band. The experiments with N-glycosidase F and WGA lectin did not reveal any N-glycosylated proteins in P. grylli spores. At the same time, incubation of major spore wall protein of 40 kDa (p40) with mannose specific lectin GNA resulted in specific binding that was reduced by pretreatment of the protein with mannosidases. Interestingly, in spite of PTP1 glycosylation, polar tube proteins extracted from P. grylli spores were not precipitated by GNA-agarose. Since P. grylli and E. cuniculi are distantly related, our data suggest that dramatic reduction of protein glycosylation machinery is a common feature of microsporidia.     

Identification of structural DNA variations in human cell cultures after long-term passage

Random amplified polymorphic DNA (RAPD) analysis was adapted for genomic identification of cell cultures and evaluation of DNA stability in cells of different origin at different culture passages. DNA stability was observed in cultures after no more than 5 passages. Adipose-derived stromal cells demonstrated increased DNA instability. RAPD fragments from different cell lines after different number of passages were cloned and sequenced. The chromosomal localization of these fragments was identified and single-nucleotide variations in RAPD fragments isolated from cell lines after 8–12 passages were revealed. Some of them had permanent localization, while most variations demonstrated random distribution and can be considered as de novo mutations.     

Weekly vs. tri-weekly cisplatin based chemoradiation in carcinoma cervix: a prospective randomized study of toxicity and compliance

BackgroundAddition of chemotherapy to radiation has improved 5-year survival by 6%. However, the optimal dose and schedule of concurrent cisplatin is not well defined, though widely accepted practice is the weekly schedule of 40 mg/m² for 5 weeks. Repeated admissions for weekly cisplatin drain the limited resources in high volume centres. We intended to study the compliance and toxicity of two cisplatin schedules in our patients diagnosed with carcinoma cervix.Materials and methodsBetween 2007–2011, 212 patients, histologically proven squamous cell carcinoma with stages IIB to IIIB were randomized into two arms. All patients were planned for external beam radiotherapy 45 Gy/25 frs over 5 weeks followed by Intracavitary or Interstitial brachytherapy to a total BED dose of 75–85 Gy. Single agent cisplatin given concomitantly, was scheduled weekly (40 mg/m²/cycle, 5 cycles) in an arm A and three weekly (100 mg/m²/cycle, 2 cycles) in an arm B. Toxicity and compliance were evaluated weekly according to the RTOG guidelines. Analysis of the compiled data was done using SSPS version 20.ResultsOf the evaluable 212, 109 patients received weekly cisplatin chemotherapy and 103 patients received three weekly cisplatin. The most common acute toxicity observed was grade I–II leucopoenia. The upper and lower gastrointestinal reactions were high in three weekly arms, which was statistically significant (57% and 42.7%, p < 0.05). Proctitis was observed in 10% of patients in both of the arms and only two patients had Gr1 Cystitis after 6 months of treatment.ConclusionsTri-weekly cisplatin based concurrent chemoradiation can be adopted in high volume centres with manageable haematological and gastrointestinal acute toxicities.     

Peculiarities of glycosylation of proteins in spores of microsporidia Paranosema (Antonospora) grylli

The long-term adaptation of microsporidia, a large group of fungi-related unicellular microorganisms, to intracellular parasitism has led to extreme minimization of the cell functional apparatus. For instance, diversity of carbohydrates in the composition of parasite glycoproteins and proteoglycans seems to be restricted to the presence of O-bound chains composed of mannose residues. This suggestion is based on the discovery in the genome of the human microsporidian Encephalitozoon cuniculi of three genes responsible for the O-mannosylation of proteins with a lack of enzymes participating in N-glycosylation. In the present work, peculiarities of protein glycosylation in spores of the microsporidian Paranosema grylli infecting the fat body of the Mediterranean field cricket Gryllus bimaculatus was studied. SDS-PAGE analysis of spore proteins with subsequent staining by periodate and Schiff reagent has shown that individual glycoproteins of P. grylli are highly glycosylated, while the maximal stain intensity was seen in the major polar-tube protein PTP1. Treatment of the extracted material with N-glycosidase F and hybridization with WGA lectin conjugated with horseradish peroxidase showed no presence of glycosylated proteins in the P. grylli spores. At the same time, the selectively extracted major protein of the exospore p40 was specifically recognized by lectin GNA conjugated with agarose balls. Pretreatment of p40 with α-and β-mannosidases decreased considerably the efficiency of binding. Since lectin GNA is specific towards mannose terminal residues, this indicates the O-mannosylation of the microsporidial exospore major protein. In spite of the intensive PTP1 glycosylation, extracted proteins of the P. grylli polar-tube had no specific binding with GNA-agarose, so the issue of peculiarities of their glycosylation remains an open question. Comparison of the obtained data with results of deciphering of the E. cuniuculi genome allows for the conclusion to be made that the minimization of the glycosylation apparatus of microsporidial proteins is the common peculiarity of this group of parasites.     

Genetic diversity and relationships in mulberry (genusMorus) as revealed by RAPD and ISSR marker assays

Background  

The genus Morus, known as mulberry, is a dioecious and cross-pollinating plant that is the sole food for the domesticated silkworm, Bombyx mori. Traditional methods using morphological traits for classification are largely unsuccessful in establishing the diversity and relationships among different mulberry species because of environmental influence on traits of interest. As a more robust alternative, PCR based marker assays including RAPD and ISSR were employed to study the genetic diversity and interrelationships among twelve domesticated and three wild mulberry species.     

Combined prime-boost vaccination against tick-borne encephalitis (TBE) using a recombinant vaccinia virus and a bacterial plasmid both expressing TBE virus non-structural NS1 protein

Background  

Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol.     

Collagenase-3 expression in periapical lesions: an immunohistochemical study

Collagenase-3 (matrix metalloproteinase-13) is a metalloproteinase (MMP) that is associated with bone lesions and exhibits variable expression patterns in odontogenic cysts; it may play a role in regulating focal proliferation and maturation of jaw cyst epithelium. We studied the localization, staining intensity and distribution of collagenase-3 in 13 periapical granulomas with epithelium, 16 periapical granulomas without epithelium and 10 radicular cysts using archived formalin fixed, paraffin embedded tissues. A monoclonal antibody against human collagenase-3 was used to evaluate its expression. Immunohistochemical staining intensities of collagenase-3 in all periapical lesions were (?), 4 (10%); (+), 1 (3%); (++), 22 (56%) and (+++), 12 (31%); differences were not statistically significant. Immunohistochemical distribution of collagenase-3 in epithelial cells was (?), 17 (44%); (+), 17 (44%); (++), 5 (13%); in fibroblasts it was (?), 8 (20%); (+), 23 (59%); (++), 8 (21%); in plasma cells it was (?), 7 (18%); (+), 22 (56%); (++), 10 (26%); in macrophages it was (?), 7 (18%); (+), and 15 (38%); and (++), 17 (44%). Statistically significant differences were found in epithelial cells (p = 0.00) and fibroblasts (p = 0.02), whereas differences were not statistically significant for plasma cells and macrophages. Collagenase-3 may play a role in the conversion of a periapical granuloma with epithelium to radicular cyst. MMP's influence not only epithelial rest cell migration, but also invasion of various stromal cells into granulomatous tissue.     

Analysis of silver binding nucleolar organizer regions in exfoliative cytology smears of potentially malignant and malignant oral lesions

Nucleolar organizer regions are nucleolar components that contain proteins that are stained selectively by silver methods; they can be identified as black dots throughout the nucleolus and are known as silver binding nucleolar organizer regions (AgNOR). The number of AgNOR is related to the cell cycle and the proliferative activity of the cells. We investigated AgNOR using exfoliative cytology smears of potentially malignant oral lesions. Eighty individuals were divided into four equal groups: healthy controls, oral leukoplakia, oral submucous fibrosis and oral squamous cell carcinoma. The mean number of AgNOR in each study group gradually increased from control to oral leukoplakia to oral submucous fibrosis to oral squamous cell carcinoma. The proliferative index was increased in the oral premalignant and malignant patients compared to normal subjects. The mean AgNOR size gradually increased from control to oral leukoplakia to oral submucous fibrosis to oral squamous cell carcinoma. Spherical shaped AgNOR were most common in controls, whereas large, clustered and kidney shapes were most common in oral squamous cell carcinoma. Multiparameter analysis of AgNOR in oral exfoliative smears is a simple, sensitive and cost-effective method for differentiating premalignant from malignant lesions and can be used in conjunction with routine cytomorphological evaluation.