Quantitative analysis of pheromone‐binding protein specificity

Many pheromones have very low water solubility, posing experimental difficulties for quantitative binding measurements. A new method is presented for determining thermodynamically valid dissociation constants for ligands binding to pheromone‐binding proteins, using β‐cyclodextrin as a solubilizer and transfer agent. The method is applied to LUSH, a Drosophila odorant‐binding protein that binds the pheromone 11‐cis vaccenyl acetate (cVA). Refolding of LUSH expressed in Escherichia coli was assessed by measuring N‐phenyl‐1‐naphthylamine (NPN) binding and Förster resonance energy transfer between LUSH tryptophan 123 (W123) and NPN. Binding of cVA was measured from quenching of W123 fluorescence as a function of cVA concentration. The equilibrium constant for transfer of cVA between β‐cyclodextrin and LUSH was determined from a linked equilibria model. This constant, multiplied by the β‐cyclodextrin‐cVA dissociation constant, gives the LUSH‐cVA dissociation constant: ～100 nM. It was also found that other ligands quench W123 fluorescence. The LUSH‐ligand dissociation constants were determined to be ～200 nM for the silk moth pheromone bombykol and ～90 nM for methyl oleate. The results indicate that the ligand‐binding cavity of LUSH can accommodate a variety ligands with strong binding interactions. Implications of this for the Laughlin, Ha, Jones and Smith model of pheromone reception are discussed.     

Food colorant Sunset Yellow (E110) intervenes developmental profile of zebrafish (Danio rerio)

In this study, we tested the teratogenic/embryotoxic potentials of food colorant, Sunset Yellow (E110) using zebrafish embryos as a model. Laboratory‐raised developing embryos of Danio rerio were exposed to graded concentrations (00, 0.1, 1.0, 2.0, 3.0, 4.0, 5.0, 10, 20, 30, 40, 50 and 100 mm ) of E110 from gastrulation stage (~6 hours post‐fertilization [hpf]) up until hatching. The developmental trajectory of each embryo and post‐hatched larva was traced from 24 to 168 hpf. The no observed effect concentration (NOEC), median effective concentration (EC₅₀), median lethal concentration (LC₅₀) and teratogenic index were determined. In the 0.1 mm E110‐exposed embryos, the development proceeded as in controls (NOEC), while, exposure of embryos to 1‐5 mm of E110 led to a decrease in body size, dry body mass of resultant larvae along with appearance of morphological deformities such as, microphthalmia, pericardial edema, yolk sac edema and spinal curvature. Larvae of 10‐50 mm E110‐exposed embryos exhibited increased cellular apoptosis in the cardiac region with significantly declined heartbeats and elevated mortality rates, in addition to the above‐mentioned abnormalities. In the 100 mm exposure group, all embryos succumbed to death within 24 hpf. The NOEC and LC₅₀ recorded were at 0.1 and 42.57 mm respectively. EC₅₀ (96 hpf) recorded for pericardial edema and yolk sac edema was 19.41 and 39.84 mm with teratogenic index quotient 2.1 and 1.06 respectively The study provides direct evidence for the developmental toxicity/teratogenic potential of E110.     

Neuro-ophthalmic presentation of COVID-19 disease: A case report

COVID-19 is a respiratory virus, which has affected various organ systems as well. Here we report a neuro-ophthalmic presentation of pituitary apoplexy under the setting of COVID-19 infection in a middle-aged man who presented to ophthalmic emergency with sudden bilateral loss of vision along with a history of fever past 10 days. There was sluggishly reacting pupils and RT-PCR for COVID was positive. Imaging pointed the diagnosis as pituitary macroadenoma with apopexy. In view of pandemic situation, patient was given symptomatic treatment as per the protocols and stabilized. Vision also showed improvement to some extent and the patient is awaiting neurosurgery     

Design,synthesis and in vitro antiplasmodial activity of some bisquinolines against chloroquine‐resistant strain

A series of novel bisquinoline compounds comprising N¹‐(7‐chloroquinolin‐4‐yl) ethane‐1,2‐diamine and 7‐chloro‐N‐(2‐(piperazin‐1‐yl)ethyl)quinolin‐4‐amine connected with 7‐chloro‐4‐aminoquinoline containing various amino acids is described. We have bio‐evaluated the compounds against both chloroquine‐sensitive (3D7) and chloroquine‐resistant (K1) strains of Plasmodium falciparum in vitro. Among the series, compounds 4 and 7 exhibited 1.8‐ and 10.6‐fold superior activity as compared to chloroquine (CQ; IC₅₀ = 0.255 ± 0.049 μm ) against the K1 strain with IC₅₀ values 0.137 ± 0.014 and 0.026 ± 0.007 μm , respectively. Furthermore, compound 7 also displayed promising activity against the 3D7 strain (IC₅₀ = 0.024 ± 0.003 μm ) of P. falciparum when compared to CQ. All the compounds in the series displayed resistance factor between 0.57 and 4.71 as against 51 for CQ. These results suggest that bisquinolines can be explored for further development as new antimalarial agents active against chloroquine‐resistant P. falciparum.     

Design,Synthesis, Biological Screening,and Molecular Docking Studies of Piperazine-Derived Constrained Inhibitors of DPP-IV for the Treatment of Type 2 Diabetes

Novel piperazine-derived conformationally constrained compounds were designed, synthesized, and evaluated for in vitro Dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. From a library of compounds synthesized, 1-(2-(4-(7-Chloro-4-quinolyl)piperazin-1-yl)acetyl)pyrrolidine ( 2g ) was identified as a potential DPP-IV inhibitor exhibiting better inhibitory activity than P32/98, reference inhibitor. The in vivo studies carried out in STZ and db/db mice models indicated that the compound 2g showed moderate antihyperglycemic activity as compared to the marketed drug Sitagliptin. A two-week repeated dose study in db/db mice revealed that compound 2g significantly declined blood glucose levels with no evidence of hypoglycemia risk. Furthermore, it showed improvement in insulin resistance reversal and antidyslipidemic properties. Molecular docking studies established good binding affinity of compound 2g at the DPP-IV active site and are in favor of the observed biological data. These data collectively suggest that compound 2g is a good lead molecule for further optimization studies.     

3'-deoxyribonucleosides and their derivatives as anti-amoebic agents

In general nucleoside analogues were found to possess in vitro amoebicidal property against trophozoites of Entamoeba histolytica. The acid-labile nature of these compounds completely destroyed their ability to cure caecal amoebiasis of rats. However the therapeutic efficacy of one of these compounds yielded most promising results, with 10% cures when it was administered as enteric coated formulation.     

Intact follicle culture: what it can tell us about the roles of FSH glycoforms during follicle development

An important limiting factor in assisted reproduction treatment success rates is oocyte quality. In spite of improved results through several important innovations, the pregnancy rate per collected oocyte remains far too low. In order to improve this situation, it is necessary to learn more about fundamental factors modulating follicular development patterns. FSH is known to be the driving force for follicle development, but it is not yet understood how its multifarious functions are controlled and modulated. Evidence is accumulating that FSH glycoforms may be the key to this mystery. Intact follicle culture is a useful tool for the clarification of the actions of the different isoforms because the follicle unit is maintained and allowed to develop through several critical stages. Additionally important is the availability of the oocyte for functional evaluation. Because of these features, relationships can be uncovered that are not revealed with single cell test systems. The results so far obtained with this system suggest that follicle development pattern and oocyte quality is strongly influenced by FSH glycoform range, and that the requirements of the follicle may shift during progress through different stages of development. More studies are required, but these findings already suggest that the physiological shifts of circulating FSH glycoforms may indeed be important, and that attention should be paid to the glycoform distribution of exogenously applied FSH.     

In vitro and in vivo antitumor properties of tetrakis((trishydroxy- methyl)phosphine)gold(I) chloride

A novel hydrophilic gold compound, tetrakis((trishydroxymethyl)phosphine)gold(I) chloride 1, has been investigated for its antitumor properties. In vitro studies demonstrate that 1 is active against HCT-15, AGS, PC-3, and LNCaP tumor cells. Cell cycle analysis of the HCT-15 cells by flow cytometry revealed elongation of the G1 phase of the cell cycle leading to growth inhibition. Administration of 1 to Balb/C mice inoculated with syngenic meth/A cells demonstrated statistically significant dose-dependent survival time.     

Serological diagnosis of human brucellosis: analysis of seven cases with neurological and cardiological manifestations

Serum Tube Agglutination (STA) test was used as routine test to detect antibrucellar antibodies in diagnosis of brucella infection in sera (n = 75) and CSF (n = 14) from 78 patients with neurological (n = 60) and cardiological (n = 15) complaints in whom brucellosis was suspected, over a period of two and a half years from January, 1997 to July 1999. Seven (neurological-six and cardiac-one) serum samples (9.33%) were positive by STA, while none of the CSFs were positive. STA titres ranged from 1:10 to 1:1280. We report the findings of these seven cases with neurological and cardiac manifestations in whom STA were found positive. Treatment was accomplished in two cases (neurological-one and cardiac-one), while remaining five cases either were treated empirically with antitubercular treatment or lost for follow up. However these reported cases should alert clinicians to investigate for Brucella infection in cases of pyrexia of unknown origin and this condition in cases of chronic meningitis with unproven aetiology.     

Osteological study of lumbar vertebrae in Western Maharashtra population

Introduction: Anatomical studies have been conducted in different ethnic groups to measure the bony vertebral dimensions and to determine the normal limits which will serve as guidelines in assessing lumbar stenosis. Aim: To determine the normal range of measurements of lumbar vertebrae in Western Maharashtra population. Materials and methods: Various dimensions of lumbar vertebrae from L₁ to L₅ were measured in 420 lumbar vertebrae, collected from the Department of Anatomy, Government Medical College, Miraj, and other Medical colleges of Western Maharashtra. Results and discussion: Mean transverse diameter of vertebral body as well as of spinal canal and anteroposterior diameter of vertebral body were minimum at L₁ and maximum at L₅. The mean anteroposterior diameter of spinal canal showed a gradual decrease from L₁ to L₅ in both sexes. Making use of the above parameters, the canal body ratio and spinal index of Jones were calculated. These parameters were also compared with those of previous studies. Similarly, from the above parameters, the values suggestive of lumbar canal stenosis and intraspinal tumor were calculated. Conclusion: The present study shows regional and ethnic variation in the parameters of lumbar vertebrae, thus emphasizing the need to determine the normal range of values for different populations.