MsDpo4—a DinB Homolog from Mycobacterium smegmatis—Is an Error-Prone DNA Polymerase That Can Promote G:T and T:G Mismatches

Error-prone DNA synthesis in prokaryotes imparts plasticity to the genome to allow for evolution in unfavorable environmental conditions, and this phenomenon is termed adaptive mutagenesis. At a molecular level, adaptive mutagenesis is mediated by upregulating the expression of specialized error-prone DNA polymerases that generally belong to the Y-family, such as the polypeptide product of the dinB gene in case of E. coli. However, unlike E. coli, it has been seen that expression of the homologs of dinB in Mycobacterium tuberculosis are not upregulated under conditions of stress. These studies suggest that DinB homologs in Mycobacteria might not be able to promote mismatches and participate in adaptive mutagenesis. We show that a representative homolog from Mycobacterium smegmatis (MsDpo4) can carry out template-dependent nucleotide incorporation and therefore is a DNA polymerase. In addition, it is seen that MsDpo4 is also capable of misincorporation with a significant ability to promote G:T and T:G mismatches. The frequency of misincorporation for these two mismatches is similar to that exhibited by archaeal and prokaryotic homologs. Overall, our data show that MsDpo4 has the capacity to facilitate transition mutations and can potentially impart plasticity to the genome

Development of a Targeted Diagnostic and Therapeutic Delivery system for Cholangiocarcinoma

The current outcomes of peri-hilar cholangiocarcinoma (PH-CCA) are in general poor with no proven roles for any treatment modalities in improving survival apart from complete surgical extirpation. The dismal prognosis observed is contributed to by both delays in diagnosis and aggressive tumour biology. The advent of molecular targeting of solid cancers allows harnessing this property on microbubble and nanotechnology based platforms. Such a system provides for concurrent diagnosis and therapeutic effect (theragnosis), the feasibility of which is explored in this work. The expression of two candidate biomarkers with established roles in cancer progression, namely Neutrophil Gelatinase-Associated Lipocalin (NGAL) and Matrix Metalloproteinase-9 (MMP9) were examined by Immunohistochemistry in 54 human samples of resected PH-CCA. These markers were then evaluated for their potential as molecular targets in theragnostic platforms in cholangiocarcinoma. Both NGAL and MMP9 were found to be abundantly expressed in both tumour tissue and control liver. Although higher NGAL expression was associated with nodal metastases, no prognostic impact was seen for either marker. NGAL expression was further interrogated in six cholangiocarcinoma cell lines by Western blotting, Immunofluorescence and ELISA techniques, which revealed localisation of NGAL to the cell membrane and its secretion, both indicating its suitability to a targeting platform. Nonetheless, its expression in normal liver tissue could lead to off-target effects. Concurrently, the expression of vascular ligands CD31, CD105 and Vascular Endothelial Growth Factor Receptor-2 were each assessed in the same cohort of tissue samples. CD105 expression was found to be independently predictive of poorer overall survival. Subsequent in vitro flow assay experiments using CD105 antibody conjugated microbubbles showed it bound murine SVR endothelial cells significantly more in comparison to isotype control microbubbles. Furthermore, evaluation of in vivo targeting with the aid of high frequency ultrasound demonstrated CD105-microbubbles bound to tumour endothelium significantly more than control microbubbles in a subcutaneous murine xenograft model of cholangiocarcinoma. This work therefore indicates NGAL is suited to a theragnostic approach in cholangiocarcinoma although larger data sets are required to explore its prognostic impact. CD105-microbubbles could be utilised in the delivery of such theragnostic particles to cholangiocarcinoma tissue, whilst in themselves providing a non-invasive index of tumour vascularity when imaged with ultrasound

Enzymatic hydrolysis of primary paper mill sludge and fermentative production of microbial lipids

Canada is known for its abundant forests and thriving forest products industry. For every ton of paper produced in mills across the country, approximately 30 kg of dry primary sludge is produced. The dry sludge is then either shipped to landfills or incinerated along with dried secondary sludge. However, this waste stream has the potential to be used more efficiently for the production of higher value products. Primary sludge is cellulosic in nature and contain fractions of hemicellulose, lignin and ash. Cellulose in the primary sludge is more accessible to enzymatic hydrolysis as compared to natural lignocellulosic biomass due to the physico-chemical treatment, that wood undergoes during pulping process. This stream was used to produce fermentable reducing sugars using enzymatic hydrolysis. Supplementation of β-glucosidase enzyme (1:0.5) reduced the time required for 35% conversion to 24 hours instead of 96 hours. The hydrolysate obtained for four days contained 41 g/l of glucose based on 81 % conversion of the cellulosic fraction in the primary sludge with β-glucosidase supplementation to a level of 1:2. The obtained hydrolysate was fermented to produce microbial lipids using oleaginous yeasts strains (Cryptococcus curvatus). The fatty acid compositions of microbial lipids produced were found to similar to vegetable oil. It thus can be used as a feedstock for the production biodiesel and other value-added products which in turn can add to the revenue of the industry

"Caught by the eye of sound" : epigastric swelling due to xiphisternal tuberculosis

BACKGROUND: Common causes of an epigastric mass include hepatomegaly, pancreatic pseudocyst and epigastric hernia, less common causes being carcinoma of the stomach or pancreas, whereas diseases of the sternum presenting as an epigastric swelling is extremely uncommon. We report a case of tubercular infection of the sternum located in the xiphoid process resulting in its presentation as an epigastric swelling. CASE REPORT: A 30-year-old immunocompetent woman with complaints of an epigastric swelling and undocumented pyrexia for four months was referred for sonographic evaluation with a clinical suspicion of an incompletely treated liver abscess. The patient was examined with ultrasound, sternal radiographs, CT and MRI. Ultrasound revealed a heterogeneous epigastric collection with linear echogenic components suggestive of bone fragments. These appearances suggested chronic infective osteomyelitis of the xiphoid process of the sternum. Lateral chest radiograph demonstrated lytic destruction of the xiphisternum. Tubercular etiology was considered and further evaluation with Multidetector Computed tomography (MDCT) and Magnetic Resonance Imaging (MRI) demonstrated erosive osteomyelitis of the xiphoid process with enhancing inflammation and collection in the adjoining soft tissue. Ultrasound-guided aspiration, PCR and Amplified Mycobacterium tuberculosis DNA test confirmed tubercular infection. CONCLUSIONS: We report a new case of osteo-articular tuberculosis localized to the xiphisternum, a rare clinical entity with an extremely unusual clinical presentation as an epigastric mass. The role of ultrasound in primary diagnosis and as an interventional diagnostic modality for guided aspiration is highlighted

ROLE OF AGNI KARMA AND SNEHAPANA IN MANAGEMENT OF PAIN IN CERVICAL SPONDYLOSIS: A CASE STUDY

Introduction: Cervical spondylosis (Greevasthamba) is a degenerative condition with pain in cervical region as a major symptom. In modern science condition is usually treated with analgesic, corticosteroids, surgical decompression, traction etc. which not contribute much promising results. But in Ayurveda several methods like Snehana, Upanaha, Agnikarma, Raktamokshana and Panchakarma etc. are specified in management of pain. Case presentation: A male patient aged 42 years admitted CARIN-MSD, IPD with pain in the neck region since 2 months, which was also radiating to the right upper limb along with numbness up to the tip of fingers. Cervical active range of motions were painful during flexion, extension and lateral rotation. Spurling test and lhermittes sign were positive. Along with the support of X- ray and MRI investigations the patient was diagnosed with cervical spondylosis due to chronic postural strain. Management and Outcome:Patient was treated with Agnikarma and Snehapana, the pain score over visual analogue scale and NPQ percentage before treatment was Nine and 87.5 % respectively while after intervention it was reduced to Two and 33.33 % within seven days. Conclusion: In acute painful stage of cervical spondylosis Agnikarma and Snehapana can play a major role in management of pain

Site-specific stable deterministic single photon emitters with low Huang-Rhys value in layered hexagonal boron nitride at room temperature

Development of stable room-temperature bright single-photon emitters using atomic defects in hexagonal-boron nitride flakes (h-BN) provides significant promises for quantum technologies. However, an outstanding challenge in h-BN is creating site-specific, stable, high emission rate single photon emitters with very low Huang-Rhys (HR) factor. Here, we discuss the photonic properties of site-specific, isolated, stable quantum emitter that emit single photons with a high emission rate and unprecedented low HR value of 0.6 at room temperature. Scanning confocal image confirms site-specific single photon emitter with a prominent zero-phonon line at ~578 nm with saturation photon counts of 105 counts/second. The second-order intensity-intensity correlation measurement shows an anti-bunching dip of ~0.25 with an emission lifetime of 2.46 ns. Low-energy electron beam irradiation and subsequent annealing are important to achieve stable single photon emitters

Knowledge, attitude, and practices of nursing mothers toward breastfeeding in a tertiary care center in Navi Mumbai

Objective: Breastfeeding (BF) has been accepted as the most vital intervention for reducing infant mortality and ensuring optimal growth and development of a child. A major barrier to successful BF is inconsistency in information and improper cultural practices. To assess the knowledge, attitude, and practices toward BF among nursing mothers following up in a tertiary care center in Navi Mumbai, Maharashtra. Methods: A community-based cross-sectional study was conducted among 512 mothers in Navi Mumbai in the state of Maharashtra, India, between January 2016 and June 2016 using a pre-set questionnaire. The mothers with children under the age of 2 years were interviewed following which descriptive statistics were obtained. Results: Our study highlights the growing awareness of the advantages of BF. Of the 512 mothers enrolled in our study, 78.9% believed in exclusive BF (EBF) till 6 months while 51% actually practiced EBF. Nearly 78% mothers felt shy to feed in public places. BF was initiated <1 h of delivery in 35.9% mothers while insufficient milk was the predominant reason (41.4%) in mothers to stop BF before 2 years. Conclusion: The majority of our participants had adequate knowledge and a positive attitude toward EBF, with right posture practiced while feeding

Effect of Space Holder Size on Microstructure, Deformation and Corrosion Response of Ti4Al4Co (wt%) Alloy Foam

In the present study, Ti4wt%Al4wt%Co alloy foam has been made using mechanically alloyed powder and elemental powder through space holder technique to investigate the mechanical and corrosion behaviour. It is noted that after sintering, the average pore sizes are 65 µm, 128 µm and 196 µm for the foam samples made by the use of space holder sizes 75 µm, 152 µm and 220 µm, respectively. It is further noted that the reduction in pore size with respect to used space holder is higher for the foam made of elementary powder. The foam made of finer space holder exhibits greater relative density and less porosity. Because of this fact, it has higher plastic collapse stress or yield stress. The foam made with elementary powder exhibited higher strength than the foam made of milled powder. The foam made with coarser pore size exhibits less corrosion rate as compared to that one with finer pore size. The foam made with elementary powder attains higher corrosion rate as compared to that one made with milled powder

On the Safety of Interpretable Machine Learning: A Maximum Deviation Approach

Interpretable and explainable machine learning has seen a recent surge of interest. We focus on safety as a key motivation behind the surge and make the relationship between interpretability and safety more quantitative. Toward assessing safety, we introduce the concept of maximum deviation via an optimization problem to find the largest deviation of a supervised learning model from a reference model regarded as safe. We then show how interpretability facilitates this safety assessment. For models including decision trees, generalized linear and additive models, the maximum deviation can be computed exactly and efficiently. For tree ensembles, which are not regarded as interpretable, discrete optimization techniques can still provide informative bounds. For a broader class of piecewise Lipschitz functions, we leverage the multi-armed bandit literature to show that interpretability produces tighter (regret) bounds on the maximum deviation. We present case studies, including one on mortgage approval, to illustrate our methods and the insights about models that may be obtained from deviation maximization.Comment: Published at NeurIPS 202