Biopolymeric Mucin and Synthetic Polymer Analogs: Their Structure, Function and Role in Biomedical Applications

Mucin networks are viscoelastic fibrillar aggregates formed through the complex self-association of biopolymeric glycoprotein chains. The networks form a lubricious, hydrated protective shield along epithelial regions within the human body. The critical role played by mucin networks in impacting the transport properties of biofunctional molecules (e.g., biogenic molecules, probes, nanoparticles), and its effect on bioavailability are well described in the literature. An alternate perspective is provided in this paper, presenting mucin’s complex network structure, and its interdependent functional characteristics in human physiology. We highlight the recent advances that were achieved through the use of mucin in diverse areas of bioengineering applications (e.g., drug delivery, biomedical devices and tissue engineering). Mucin network formation is a highly complex process, driven by wide variety of molecular interactions, and the network possess structural and chemical variations, posing a great challenge to understand mucin’s bulk behavior. Through this review, the prospective potential of polymer based analogs to serve as mucin mimic is suggested. These analog systems, apart from functioning as an artificial model, reducing the current dependency on animal models, can aid in furthering our fundamental understanding of such complex structures

Monovalent ions modulate the flux through multiple folding pathways of an RNA pseudoknot

The functions of RNA pseudoknots (PKs), which are minimal tertiary structural motifs and an integral part of several ribozymes and ribonucleoprotein complexes, are determined by their structure, stability and dynamics. Therefore, it is important to elucidate the general principles governing their thermodynamics/folding mechanisms. Here, we combine experiments and simulations to examine the folding/unfolding pathways of the VPK pseudoknot, a variant of the Mouse Mammary Tumor Virus (MMTV) PK involved in ribosomal frameshifting. Fluorescent nucleotide analogs (2-aminopurine and pyrrolocytidine) placed at different stem/loop positions in the PK, and laser temperature-jump approaches serve as local probes allowing us to monitor the order of assembly of VPK with two helices with different intrinsic stabilities. The experiments and molecular simulations show that at 50 mM KCl the dominant folding pathway populates only the more stable partially folded hairpin. As the salt concentration is increased a parallel folding pathway emerges, involving the less stable hairpin structure as an alternate intermediate. Notably, the flux between the pathways is modulated by the ionic strength. The findings support the principle that the order of PK structure formation is determined by the relative stabilities of the hairpins, which can be altered by sequence variations or salt concentrations. Our study not only unambiguously demonstrates that PK folds by parallel pathways, but also establishes that quantitative description of RNA self-assembly requires a synergistic combination of experiments and simulations.Comment: Supporting Information include

IDENTIFICATION AND ANTIMICROBIAL SUSCEPTIBILITY TESTING OF PATHOGENIC MICRO-ORGANISM FROM DENTAL PATIENTS

ABSTRACTObjective: To isolate and identify aerobic microbes present in the periodontal infected patients and to evaluate the choice of antibiotics in themanagement of periodontal diseases.Methods: In this study, these patients have not been treated previously for their conditions. An informed consent was obtained from these patientsbefore collection of an oral swab. This study was approved by the Institutional Ethical Committee. The details of the patient's age, sex, and clinicaldetails were recorded on a per forma meant for this study. The following methodologies were adopted for the isolation and identification of the microorganismsfromthese cases.Results: In this study out of 50 oral samples, culture positivity was recorded in 43 (86%) cases and no growth in 7 (14%) cases. Antibiotic susceptibilitytest using to identified as resistant, sensitive, intermediate of pathogenicity of oral microbes. Such antibiotics were methicillin, ceftazidime,clindamycin, amikacin, cloxacillin, and cefotaxime. This study should be kept in mind when a local application of antibacterial compounds is used inthe therapy of periodontal disease.Conclusion: This study highlights the different organisms involved in the different types of dental infections. The antibiotic pattern shown in this workwill be a guide to the clinician in the selection of proper antibiotics for the treatment of these infections. Hence in this study, the limitations were timeand the number of patients. For better outcomes, a larger study population for a longer period of time should be undertaken to know the bacteriologyand to the select the effective drugs of choice for dental infections. A comparative study of bacteriology and mycology and its antimicrobial propertywould be very fruitful in the future.Keywords: Dental, Periodontal, Bacteria, Antibiotics

PREVALENCE OF CEPHALOSPORIN-RESISTANT GRAM-NEGATIVE BACILLI FROM CLINICAL SAMPLES

ABSTRACTObjective: Beta-lactams are the group of antibiotics that contain a ring called as beta-lactam ring,†which is responsible for the antibacterial activity.The presence of resistance among Gram-negative organisms is due to the production of beta-lactamases enzymes that hydrolysis the beta-lactam ringthereby conferring resistance to the organism. This study is undertaken to determine the prevalence of extended-spectrum beta-lactamase (ESBL)producing Gram-negative organism from clinical samples.Methods: A total of 112 clinical samples were taken for this study. The combined disc synergistic test (CDST) was used for the phenotypic detectionof ESBL producers from the clinical samples. The genotypic identification of ESBL producers was carried out by alkaline lysis method by isolation ofplasmid DNA.Result: A total of 87 bacterial isolates were isolated and identified. Among them, Klebsiella (41%) was the predominant organism followed byEscherichia coli (33%), Proteus (10%), Pseudomonas (10%), and Serratia (6%). Among the various bacterial isolates, Klebsiella showed a higherpercentage of resistance. The CDST showed that 8 isolates of Klebsiella, 3 isolates of E. coli, and 1 isolate of Pseudomonas were found to be ESBLproducers. The genotypic confirmation showed that the two bacterial isolates, namely, Klebsiella and E. coli were found to possess temoniera (TEM)gene which was the 400-500 bp conferring resistance to the antibiotics.Conclusion: The results of this study suggest that early detection of ESBL producing Gram-negative organism is a very important step in planning thetherapy of patient in Hospitals. CDST continues to be a good indicator in the detection of ESBL producers.Keywords: Beta-lactamases, Gram-negative bacilli, Extended-spectrum beta-lactamase, Resistance, Combined disc synergistic test.Â

CLINICO – MYCOLOGICAL PROFILE OF DERMATOPHYTIC INFECTIONS

Objective: The objective of this study was to isolate and identify the dermatophytic infected patients attending Perunduarai IRT Medical College and Hospital, Erode.Methods: The samples of skin, nail and hair from patients having the sign of superficial mycoses were gathered over a period of one year. The clinical material was examined microscopically by KOH mount and the culture was done on Sabouraud dextrose agar, Potato dextrose agar Dermatophyte test agar medium and incubated at 28-30 °C.Results: The demographic data shows that the men (82%) were highly susceptible to the infection; the infected age group is between 15-30 y (74%). In that students, (28%) were highly exposed to Tinea corporis and Tinea cruris infection.Conclusion: The results of the study suggested that the preliminary information on the prevalence and distribution of dermatophytes in the area of sampling. So the knowledge of the efficient screening, management, reduction and treatment of the dermatophytic infection should be fruitful in the future.Keywords: Skin, KOH mount, Dermatophyte test medium (DTM), Tinea cruri

ISOLATION AND IDENTIFICATION OF ENDOPHYTIC FUNGI FROM TERMINALIA CHEBULA OF EASTERN GHATS, TAMILNADU

Objective: Endophytic fungi live inside the higher plants, apparently without causing any harm to the hosts and its produce the secondary metabolites are potential antimicrobial activity. Terminalia chebula has been used in Ayurveda, Unani & Homeopathy medicine. In this study an isolate and identify the endophytic fungi from T. Chebula collected from pachamalai hills of the Eastern Ghats, Tamilnadu.Methods: The plant materials were taken and first rinsed in running tap water to remove the dust and the other debris present in it. Segments of approximately 0.5 cm were cut in sterile lancet blades and surface sterilized by agitating in 70% ethanol (5s), followed by treatment with 4% NaOCl (90s) and then rinsed in sterile distilled water (10s).Thirty six (leaf, stem and fruit samples) segments from T.chebula plant are processed for the isolation of endophytic fungi.Results: About 36 segments (12 segments of each part respectively) of the medicinal plant were screened for the isolation of the endophytic fungi. A total of 27 endophytic fungi was isolated and identified from medicinal plant T.chebula. The leaf segments showed a maximum repository for endophytic fungi than the other segments. Among the 27 endophytic fungi, the predominant endophytic fungi isolated belonged to the genera of Alternaria longipes, Curvularia spp, Mucor, phoma spp, Aspergillus niger, Aspergillus flavus and Penicillium spp. In this study majority of the fungi belonged to hyaline hyphomycetes.Conclusion: In this study conclude that the isolation of endophytic fungi from medicinal plant of terminalia chebula. To isolate the 27 endophytic fungi produce the novel bioactive compound. However Further studies are required to screen these endophytic fungi for production of novel Bioactive compounds.Keywords: Endophytic fungi, Terminalia chebula, bioactive compoundÂ

Refeeding Enteroclysis: An Alternative to Total Parenteral Nutrition in Small Bowel Ostomies

INTRODUCTION In the course of an intestinal surgery procedure, several clinical situations lead the surgeon to undertake a double temporary enterostomy (small bowel resection, peritonitis, fistulae, anastomosis protection...) or could be complicated of enterocutaneous fistula (ECF) (peritonitis, anastomosis leakage, digestive adherences…). These conditions could constitute a short bowel syndrome and are often complicated with intestinal failure (IF), especially when the stoma output is equal or higher than 1500 ml/24h. These lead to serious complications resulting in hospital readmissions, such as acute or chronic dehydration, renal failure, electrolyte disturbances, micronutrients and mineral deficiencies, and malnutrition, thus increasing healthcare-related costs and affecting patients’ quality of life [1]. IF was recently defined by the European Society for Clinical Nutrition and Metabolism (ESPEN) as “the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth” [2]. In case of temporary double enterostomy or ECF, the IF is type 2, and defines as a prolonged acute condition, often in metabolically unstable patients, requiring complex multi-disciplinary care and intravenous supplementation over periods of weeks or months [2]. At this time, the current gold standard therapy indicated until the surgical reestablishment of digestive continuity is home parenteral nutrition (HPN) [3]. However, HPN has its own morbidity and, in the absence of expertise, the risks of infectious, hepatic dysfunction, mechanical and metabolic complications are increased [1,3]. Therefore, the availabilities of low cost, safer, and easy-to-use nutrition support techniques could be of high added value in these type 2 IF patients. Refeeding enteroclysis [5,6,10] could be the technique. AIMS & OBJECTIVES: A clinical study to determine the technical principles of refeeding enteroclysis and its beneficial effects in their clinical practice and reducing the need for parenteral nutrition. MATERIALS AND METHODS PLACE OF STUDY: Department of General Surgery, Govt. Stanley Medical College & Hospital, Chennai. DURATION: 12 months. STUDY DESIGN: Non Randomized single blinded open labelled control trial. SAMPLE SIZE : 32. Sample size is calculated using Openepi software version 3.0 With the expected mean difference is mean number of days of TPN needed between the intervention and control group to be 28, the sample size is estimated at 16 in each arm with 95% confidence level, 80% power and ratio between intervention and control arm as 1:1 INCLUSION CRITERIA: Age >14 years Existence of a double/loop enterostomy or at least two orifices of ECF visible on the abdominal wall. Absence of obstruction of digestive fistula between the mouth and the afferent stoma, and in the efferent intestinal tract; Ability to catheterize the efferent stoma with a feeding tube on more than 15cm; Full agreement of the patient to carry out enteroclysis and accept the food constraints of ingesting smooth pure meals. EXCLUSION CRITERIA: Patient not willing for the procedu. Colostomy/sigmoidostomy done patients. Presence of obstruction of digestive tract between the mouth and the afferent stoma, and in the efferent intestinal tract. Patients with CKD/DCLD/Malignancy. METHODOLOGY: To obtain informed consent from all subjects before enrollment in the study. Patients are separated into 2 groups of 16 each control and study group. GROUP A : This is a test group with patients in this group are subjected to refeeding enteroclysis in a method described below and the need for total parenteral nutrition despite refeeding enteroclysis is noted. GROUP B : This is a control group with patients in this group are not subjected to refeeding enteroclysis but managed with Total parenteral nutrition if needed. Patients who are included in the study are started with enteral feeding on 1st postoperative day and the ostomy output will be monitored and refeeding will be started once the ostomy starts functioning. Before refeeding is initiated , one liter of oral rehydration solution, together with laxatives in case of fecal residues or fecaloma in the colon are given. At the same time, anti-motility drugs are stopped to prevent ileus. Antispasmodic agents could be useful in case of abdominal pain, and cholestyramine is given by enteroclysis in the event of diarrhea during the first days. Ostomy output collected from the afferent limb preserved after sieving to remove large food particle, every 6th hourly. A nasogastric tube after applying topical anaesthetic agent is inserted into the efferent limb of a length 10cm and fixed out through the ostomy bag. The preserved collection from the afferent limb is reinfused over the efferent limb via the nasogastric tube every 6th hourly. Ostomy output from the afferent limb, reinfused content volume over the efferent limb are recorded. Patient are maintained on strict input/output chart,weight chart,renal and hepatic parameters are monitored serially and the signs of dehydration are noted. Total parenteral nutrition of volume 1litre via central venous cannulation will be used in the study. Data were analyzed using the unpaired two-tailed t-tests and chisquare analysis and the results are tabulated. RESULT : Among 32 patients included in the study, in the test group A the usage of TPN was 18.75% when compared to control group B is 62.50% and the result was stastically significant with the p value 0f 0.029.The mean age group being 52 and th common cause of small bowel ostomy being SMA thrombosis. CONCLUSION : Refeeding enteroclysis serve as an alternative to total parenteral nutrition among small bowel stoma patients and their co-relation was established in the study. Refeeding enteroclysis being cost effective and also decreases the complication among high output stoma and alleviating the parenteral nutrition dependence

Co-Opting ATP-Generating Glycolytic Enzyme PGK1 Phosphoglycerate Kinase Facilitates the Assembly of Viral Replicase Complexes

The intricate interactions between viruses and hosts include exploitation of host cells for viral replication by using many cellular resources, metabolites and energy. Tomato bushy stunt virus (TBSV), similar to other (+)RNA viruses, induces major changes in infected cells that lead to the formation of large replication compartments consisting of aggregated peroxisomal and ER membranes. Yet, it is not known how TBSV obtains the energy to fuel these energy-consuming processes. In the current work, the authors discovered that TBSV co-opts the glycolytic ATP-generating Pgk1 phosphoglycerate kinase to facilitate the assembly of new viral replicase complexes. The recruitment of Pgk1 into the viral replication compartment is through direct interaction with the viral replication proteins. Altogether, we provide evidence that the ATP generated locally within the replication compartment by the co-opted Pgk1 is used to fuel the ATP-requirement of the co-opted heat shock protein 70 (Hsp70) chaperone, which is essential for the assembly of new viral replicase complexes and the activation of functional viral RNA-dependent RNA polymerase. The advantage of direct recruitment of Pgk1 into the virus replication compartment could be that the virus replicase assembly does not need to intensively compete with cellular processes for access to ATP. In addition, local production of ATP within the replication compartment could greatly facilitate the efficiency of Hsp70-driven replicase assembly by providing high ATP concentration within the replication compartment

A review on novel COVID-19: background, etiology, pathogenesis, transmission, prevention and management

Mankind's history is watching a bizarre time battling an imperceptible adversary, the novel COVID-19 Coronavirus. At first seen in the Wuhan province of China, presently limitlessly spreading all over world. How the COVID 19 has been made on the globe become Pandemic needs no depiction. The virus has been accounted for affecting the lungs and related respiratory tracts promoting harm of the alveoli. It has been accounted that the respiratory sickness is the prevailing Clinical symptom of COVID-19. This review article discusses an easily understanding of the causes, different type of Human viruses regarded of Coronavirus, clinical diagnosis of RT-PCR, FET, Primary prevention and control of the virus. Therefore, this review article main theme is to provide more reliable and valid information to control and manage public emergency in both acute and chronic conditions of coronaviru

Coordinated Function of Cellular DEAD-Box Helicases in Suppression of Viral RNA Recombination and Maintenance of Viral Genome Integrity

The intricate interactions between viruses and hosts include an evolutionary arms race and adaptation that is facilitated by the ability of RNA viruses to evolve rapidly due to high frequency mutations and genetic RNA recombination. In this paper, we show evidence that the co-opted cellular DDX3-like Ded1 DEAD-box helicase suppresses tombusviral RNA recombination in yeast model host, and the orthologous RH20 helicase functions in a similar way in plants. In vitro replication and recombination assays confirm the direct role of the ATPase function of Ded1p in suppression of viral recombination. We also present data supporting a role for Ded1 in facilitating the switch from minus- to plus-strand synthesis. Interestingly, another co-opted cellular helicase, the eIF4AIII-like AtRH2, enhances TBSV recombination in the absence of Ded1/RH20, suggesting that the coordinated actions of these helicases control viral RNA recombination events. Altogether, these helicases are the first co-opted cellular factors in the viral replicase complex that directly affect viral RNA recombination. Ded1 helicase seems to be a key factor maintaining viral genome integrity by promoting the replication of viral RNAs with correct termini, but inhibiting the replication of defective RNAs lacking correct 5\u27 end sequences. Altogether, a co-opted cellular DEAD-box helicase facilitates the maintenance of full-length viral genome and suppresses viral recombination, thus limiting the appearance of defective viral RNAs during replication