Development of polyclonal ELISA for the N-methylcarbamate insecticide bendiocarb

A polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA) method was developed for the N-methylcarbamate insecticide bendiocarb (2,2-dimethyl-1,3-benzodioxol-4-yl methylcarbamate). Two novel haptens having dimethylbenzodioxyl and dimethylbenzofuranyl groups connected to oxyacetyl-γ-aminobutanoic acid and oxyacetyl-β-alanine spacer arm respectively were synthesised. The first hapten was conjugated to carrier proteins to make antigens that were used to raise polyclonal antibodies in rabbits. The antibodies specifically recognised bendiocarb and its metabolite 2,2-dimethyl-1,3-benzodiox-4-ol with an IC₅₀ value of 9 ppb (ng ml^-1). The assay was standardised using the competitive ELISA format at 0.0625 µg antibody concentration and at 1/10k pesticide-HRP dilution. Matrix effect studies were carried out in four vegetable and cereal food samples. Matrix effect elimination in cabbage, cauliflower and rice was achieved by simple dilution of the extract. Five different approaches were attempted to achieve matrix clean up in paddy rice. C-18 column and gel permeation column chromatography (GPC) helped in the matrix removal. The spike and recovery studies for all the four food samples gave a recovery in the range of 75-95%, thus indicating the efficiency of the matrix elimination procedures developed.     

Exosomes: Emerging implementation of nanotechnology for detecting and managing novel corona virus- SARS-CoV-2

The spread of SARS-CoV-2 as an emerging novel coronavirus disease (COVID-19) had progressed as a worldwide pandemic since the end of 2019. COVID-19 affects firstly lungs tissues which are known for their very slow regeneration. Afterwards, enormous cytokine stimulation occurs in the infected cells immediately after a lung infection which necessitates good management to save patients. Exosomes are extracellular vesicles of nanometric size released by reticulocytes on maturation and are known to m...     

PROP test: prediction of caries risk by genetic taste perception among the visually impaired children

The study sample consisted of 100 children with visual impairment aged 6–14 years. 6‐n‐propylthiouracil (PROP) sensitivity test was carried out. The Caries experience was recorded, estimation of Streptococcus mutans done and their taste likes and dislikes assessed through a food preference questionnaire. The Caries experience and S. mutans levels were highest in the non‐tasters, comparatively low in medium tasters and the least in the supertasters. Dietary preferences indicated tasters were sweet dislikers and non‐tasters, sweet likers. PROP test can be a useful tool in determining genetic taste sensitivity levels amongst the visually impaired children and thus used as a screening tool in those children who are at a high risk of developing dental caries.     

The developmental stages of the middle phalanx of the third finger (MP3): a sole indicator in assessing the skeletal maturity?

Assessment of skeletal maturity is an integral part of interceptive diagnosis and treatment planning. The present day methods of skeletal maturity assessment like the hand-wrist radiographs or cervical vertebrae radiographs are expensive, require elaborate equipment and accounts for high radiation exposure, especially for growing children. The present study was thus undertaken to provide a simple and practical method of skeletal maturity assessment using the developmental stages of the middle phalanx of the third finger (MP3) as seen on an IOPA film taken using a standard dental x-ray machine. The results of the study showed that this simple method was highly reliable and could be used as an alternative method to assess the skeletal maturity of growing children.     

Tuberous sclerosis: a case report

A case of tuberous sclerosis (TS) with classic triad of seizures, mental deficiency and angiofibromas is presented. The child also presented with self-mutilating behavior, which resulted in the fracture of her anterior teeth. A comprehensive treatment was rendered to the patient under general anesthesia and a mouth guard was given to prevent further trauma to the teeth.     

Kidney stones and the ketogenic diet: risk factors and prevention

A cohort study was performed of children started on the ketogenic diet for intractable epilepsy from 2000 to 2005 (n = 195). Children who developed kidney stones were compared with those without in terms of demographics, urine laboratory markers, and intervention with urine alkalinization (potassium citrate). Thirteen children (6.7%) developed kidney stones. The use of oral potassium citrate significantly decreased the prevalence of stones (3.2% vs 10.0%, P = .049) and increased the mean time on the ketogenic diet before a stone was first noted (260 vs 149 patient-months, P = .29). The prevalence of kidney stones did not correlate with younger age or use of carbonic anhydrate inhibitors (eg, topiramate or zonisamide) but trended toward higher correlation with the presence of hypercalciuria (92% vs 71%, P = .08). No child stopped the diet due to stones; in fact, the total diet duration was longer (median 26 vs 12 months, P < .001). Kidney stones continue to occur in approximately 1 in 20 children on the ketogenic diet, and no statistically significant risk factors were identified in this cohort. As oral potassium citrate was preventative, prospective studies using this medication empirically are warranted.     

Saponins from Quillaja saponaria Molina: isolation, characterization and ability to form immuno stimulatory complexes (ISCOMs)

ISCOMs have received much attention as vaccine adjuvants due to their immunostimulatory effects. They are colloidal particles typically comprised of phospholipids, cholesterol and Quil A, a crude mixture of saponins extracted from the bark of Quillaja saponaria Molina. We have previously shown that ISCOMs can be prepared by ether injection wherein an ether solution of phospholipids and cholesterol in a mass ratio of 5:2 is injected into a solution of Quil A at a mass ratio of 7 lipids: 3 Quil A. The aim of this study was firstly to isolate and characterise discrete fractions of Quil A and secondly to investigate which of these fractions were able to form ISCOMs by the method of ether injection. Six fractions of Quil A were isolated by semi-preparative reverse phase high performance liquid chromatography (RP-HPLC) and characterised by analytical HPLC, liquid chromatography tandem mass spectrometry (LC-MS) and the qualitative Liebermann-Burchard and Molisch tests for triterpenoids and carbohydrates respectively. ISCOMs were subsequently prepared from the isolated fractions by the method of ether injection and the resulting preparations characterized by photon correlation spectroscopy (PCS) and negative stain transmission electron microscopy (TEM). The molecular weights of the major compounds in the fractions ranged from approximately 1200 to approximately 2300 Da; all fractions tested positive for triterpenoids and saccharides and four of the fractions were identified as QS-7, QS-17, QS-18 and QS-21 by analysis (LC-MS and analytical HPLC). Injection of ether solutions of lipids into aqueous solutions of QS-17, QS-18 or QS-21 all resulted in homogeneous ISCOM dispersions. The combination of lipids and QS-7 by ether injection produced lamellae and liposomes as the prominent structures and a minor amount of ISCOMs. The remaining two hydrophilic, low molecular weight fractions of Quil A did not produce ISCOMs, instead liposomes and helical structures predominated in the samples.