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Wireless sensor network (WSN) is assortment of sensor nodes proficient in environmental information sensing, refining it and transmitting it to base station in sovereign manner. The minute sensors communicate themselves to sense and monitor the environment. The main challenges are limited power, short communication range, low bandwidth and limited processing. The power source of these sensor nodes are the main hurdle in design of energy efficient network. The main objective of the proposed clustering and data transmission algorithm is to augment network performance by using swarm intelligence approach. This technique is based on K-mean based clustering, data rate optimization using firefly optimization algorithm and Ant colony optimization based data forwarding. The KFOA is divided in three parts: (1) Clustering of sensor nodes using K-mean technique and (2) data rate optimization for controlling congestion and (3) using shortest path for data transmission based on Ant colony optimization (ACO) technique. The performance is analyzed based on two scenarios as with rate optimization and without rate optimization. The first scenario consists of two operations as kmean clustering and ACO based routing. The second scenario consists of three operations as mentioned in KFOA. The performance is evaluated in terms of throughput, packet delivery ratio, energy dissipation and residual energy analysis. The simulation results show improvement in performance by using with rate optimization technique. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus (S. aureus) remains, to date, one of the major causes of both Healthcare Associated (HA) and Community Associated (CA) infections. S. aureus causes a variety of infections, ranging from Skin and Soft Tissue Infections (SSTI) to life threatening endocarditis. Healthcare Associated Methicillin-resistant Staphylococcus aureus (HA-MRSA) and Communityassociated Methicillin-resistant Staphylococcus aureus (CA-MRSA) have been increasingly reported from India. Efficacious dissemination of the complex and heterologous Staphylococcal Cassette Chromosome (SCC) mec elements necessitate to detect its SCC mec typing. Panton-Valentine Leucocidin (PVL) is a cytotoxin produced by S. aureus associated CA infections of S. aureus. Aim and Objectives: To investigate the prevalence of HA-MRSA and CAMRSA in tertiary care hospital and to analyse the demographic and clinical characteristics of patients with Methicillin-resistant Staphylococcus aureus (MRSA) infections with mec A gene and PVL gene-positive strains and to compare with those for PVL gene-negative strains. Material and Methods: Isolation and identification has been done by standard conventional methods. Results: A total of 400 MRSA; 107 (26.75%) MRSA were from blood sample of Body Substance Isolation (BSI) and endocarditis 81(20.25%) were from osteomyelitis and septic arthritis, 97(24.25%) were from skin and soft tissue infections, 62(15.5%) were from pneumonia, 45(11.25%) were from Urinary Tract Infection (UTI). Of the total 400 MRSA strains; 183(45.75%) strains were isolated from paediatric and neonatal age group. All MRSA strians were susceptible to tigecycline and vancomycin. 95.5% strains were susceptible to linezolid. Of the total MRSA;40.5% strains were susceptible for clindamycin and all strains isolated from SSTIs were susceptible clindamycin. MRSA strains 248(62%) were resistant to tetracycline. 75.25% and 42.75% MRSA strains were defined as CA-MRSA and HA-MRSA respectively by clinical criteria: CDC epidemiologic definitions.76% (41/54) of patient isolates had presence of both the genes in the genome whereas 16% had only mecA gene. Small percent of isolates (5.5%) did not have both the genes on the genome. Conclusion: Our laboratory analysis of MRSA isolates indicated a high number of PVL-positive CA-MRSA isolates, carrying a novel mecA gene. The co-occurrence of multidrug-resistant MRSA and PVL-positive CA-MRSA highlights the risk for the emergence of a multidrug-resistant PVLpositive MRSA clone. [ABSTRACT FROM AUTHOR]

Introduction: Invasive fungal infections are an important nosocomial health problem, candidal infections being the most common. Candidal bloodstream infections (BSIs) account for one fourth of the nosocomial BSIs. Candida albicans once the most common has now been replaced by nonalbicans Candida, accounting for majority of cases of candidal infections. The knowledge and understanding of specific risk factors, epidemiology, prophylactic measures, and outcomes with relation to speciation are changing rapidly. Emergence of antifungal resistance is a cause of concern. With this background, a prospective study was undertaken. Aims and Objectives: To isolate Candida spp. from blood cultures of patients with clinically diagnosed or suspected septicemia; to identify and speciate Candida isolates and carry out the antifungal susceptibility test; to determine incidence of candidemia; to find out the crude mortality rate in candidemia patients. Materials and Methods: Blood cultures received in the Department of Microbiology from various critical care units over a 1 year period were included in this study. Samples were cultured on Sabouraud dextrose agar and routine bacteriological cultures. Speciation of suspected Candida growth was done by conventional and automated system. Results: A total of 225 out of 839 blood cultures were culture positive. A total of 196 were bacterial pathogens. Candida spp. were isolated in 29 samples. These included 10 cases of Candida tropicalis, 8 Candida parapsilosis, and three cases each of C. albicans and Candida krusei. Fluconazole resistance was seen (minimum inhibitory concentration ⩾64 μg/ml) in 4 isolates, 2 of C. krusei and 2 of Candida haemulonii. Incidence of candidemia was 3.46%. Crude mortality rate in the present study was 24%. [ABSTRACT FROM AUTHOR]

Background: Catheter-associated urinary tract infection (CAUTI) is the most common nosocomial infection. The etiological agents of which may be varied. Advancing age, debilitation, diabetes mellitus, duration of catheterization are the risk factors. Complications include prostatitis, epididymitis, cystitis, pyelonephritis and septicemia in high-risk patients, adding to hospitalization and morbidity. With this background the present study was undertaken Objectives: (1) To identify microbial pathogens associated with urinary tract infection (UTI) in catheterized patients from Intensive Care Units (ICU) (2) to determine the susceptibility pattern of these isolates to antimicrobial agents (3) to determine the effect of days of catheterization and UTI. Materials and Methods: Consecutive urine samples of 345 catheterized patients admitted in ICUs were included in the study. They were processed by standard microbiological procedures. Isolated organisms were speciated, and antibiotic susceptibility performed as per standard guidelines. Results: From the 345 urine samples of catheterized patients, 205 showed no growth and were found to be sterile. Bacterial growth was seen in 69 patients and fungal growth in 50 patients. Among the bacterial isolates, Escherichia coli were isolated in 39, followed by Klebsiella spp. 14. The other isolates included Pseudomonas spp., Group D streptococci and methicillin-resistant Staphylococcus aureus. In the fungal isolates, Candida glabrata was the most common isolate. High resistance was seen among Klebsiella isolates (nalidixic acid-86% and cefotaxime-86%). Conclusion: Development of CAUTI is common in critically ill patients. Emphasis should be placed on good catheter management and reducing the duration of catheterization rather than prophylaxis in order to reduce the incidence of catheter-related UTI. Culture and susceptibility testing play a vital role in the management if UTI occurs. [ABSTRACT FROM AUTHOR]

Tuberculosis, a contagious bacterial disease which is caused by Mycobacterium tuberculosis, primarily involves the lungs.Though Pulmonary tuberculosis (PTB) is the commonest clinical presentation, there is a need for alertness towards uncommon presentations which involve other organs. Tuberculous otitis media (TOM) is one such rare presentation seen in paediatric practice. It is characterized by painless otorrhoea which fails to respond to the routine antibacterial treatment. TOM usually occurs secondary to PTB. Here is a case of tuberculous otitis media with Proteus mirabilis co-infection, with no evidence of PTB. In the sample of ear discharge obtained from the patient, acid fast bacilli were demonstrated on direct microscopy after Ziehl-Neelsen staining. Culture done on Lowenstein-Jensen medium demonstrated slow-growing Mycobacterium. Bacteriological culture and identification helped in isolating Proteus mirabilis. PCR, followed by Line- Probe Assay for early identification and susceptibility testing to primary drugs, was done. Further, patient tested negative for the Mantoux test. Patient was enrolled in National Tuberculosis programme- RNTCP. This case emphasizes on one of the less common presentations of a common disease. A high clinical suspicion and laboratory confirmation are required for appropriate patient management. [ABSTRACT FROM AUTHOR]

Background: In the past few years, there has been an increase in infections caused by fungal aetiology. This is mainly due to increase in sizes of populations which are at risk. Also, fungi which were previously considered as non-pathogenic have been increasingly implicated. Hence, this study was taken up. Aim: To assess the magnitude of mycotic infections in this set up. To assess the spectrum of fungi which are involved in various infections. Material and Methods: Total 704 samples taken over two and half period were included. They consisted of various samples like sputum, blood, urine, sterile body fluids, corneal scrapings. These were processed by conventional mycological techniques. These included direct microscopy after Gram staining and KOH mount, culture on Sabouraud's dextrose agar (SDA), corn meal agar, brain heart infusion (BHI), brain heart infusion agar (BHIA) and others, as required. For non-albicans Candida, the automated Vitek 2 C system was used. Various moulds and yeasts were identified up to genus level and species level. Results: Of 704 samples, 336 (48%) were positive for fungal culture. Of these, 244 isolates were yeast like fungi, 81 were moulds, 7 were yeasts and 4 were dimorphic. Among blood stream infections, non-albicans Candida were the commonest isolates. In the urine samples, C. albicans was the commonest isolate. From corneal scrapings, only moulds and dimorphic fungi were isolated. Conclusion: Incidence of non- albicans Candidal infections is increasing. Culture and identification of mycotic infections is essential for commencement of suitable antifungal therapy. [ABSTRACT FROM AUTHOR]

Background: Chromoblastomycosis is a non-contagious, chronic localized fungal infection of cutaneous and sub-cutaneous tissues caused by several species of phaeoid (ie. Dematiaceous) fungi. It usually known to occur following trauma with wood splinters and usually occurs on the hands, feet and legs. Diagnosis can be made by direct microscopic demonstration of pathognomic brown sclerotic cells in skin scrapings and a positive fungal culture, confirms the same. Case Presentation: A 40-years old male presented with complaints of slowly spreading raised hyperpigmented lesions, three in number over right side of face and solitary plaque over lip with mild scaling from last six months and it was not associated with itching. Patient did not have any history of injury over the face with wooden splinters. The patient was initially suspected to have Lichen planus and was treated accordingly. But condition of the patients did not improve. He was then sent for Microbiological diagnosis. Laboratory Diagnosis: The diagnosis of Chromoblastomycosis was made by demonstration of sclerotic bodies with transverse septa arranged in cluster on KOH examination. Isolation of Fonsecaea pedrosii on SDA confirmed Chromoblastomycosis. Conclusion: Although Chromoblastomycosis is very rare on the face, our case demonstrates the need for consideration of Chromoblastomycosis in the differential diagnosis of resistant verrucous plaques of the face. We report an unusual case of Chromoblastomycosis for the first time from the state of Maharashtra and probably second case from India. [ABSTRACT FROM AUTHOR]

Background and Objectives: Methicillin resistance is acquired by the bacterium due to mecA gene which codes for penicillin-binding protein (PBP2a) having low affinity for β-lactam antibiotics. mecA gene is located on a mobile genetic element called staphylococcal cassette chromosome mec (SCC mec ). SCC mec genomic island comprises two site-specific recombinase genes namely ccrA and ccrB [cassette chromosome recombinase] accountable for mobility. Currently, SCC mec elements are classified into types I, II, III, IV and V based on the nature of the mec and ccr gene complexes and are further classified into subtypes according to variances in their J region DNA. SSC mec type IV has been found in community-acquired isolates with various genetic backgrounds. The present study was undertaken to categorize the types of SCC mec types and subtypes I, II, III, IVa, b, c, d, and V and PVL genes among clinical MRSA isolates from COVID-19 confirmed cases., Materials and Methods: Based on the Microbiological and Molecular ( mecA gene PCR amplification) confirmation of MRSA isolated from 500 MRSA SCC mec clinical samples, 144 cultures were selected for multiplex analysis. The multiplex PCR method developed by Zhang et al. was adapted with some experimental alterations to determine the specific type of these isolates., Results: Of the total 500 MRSA, 144 MRSA (60 were CA-MRSA and 84 were HA-MRSA) were selected for characterization of novel multiplex PCR assay for SSC mec Types I to V in MRSA. Molecular characterization of multiplex PCR analysis revealed results compare to the phenotypic results. Of the 60 CA-MRSA; in 56 MRSA strains type IVa was found and significantly defined as CA-MRSA while 4 strains showed mixed gens subtypes. Type II, III, IA, and V were present in overall 84 HA-MRSA. Molecular subtyping was significantly correlated to define molecularly as CA-MRSA and HA-MRSA however 15 (10%) strains showed mixed genes which indicates the alarming finding of changing epidemiology of CA-MRSA and HA-MRSA as well., Conclusion: We have all witnessed of COVID-19 pandemic, and its mortality was mostly associated with co-morbid conditions and secondary infections of MDR pathogens. Rapid detections of causative agents of these superbugs with their changing epidemiology by investing in typing and subtyping clones are obligatory. We have described an assay designed for targeting SSC mec types and subtypes I, II, III, IVa,V according to the current updated SCC mec typing system. Changing patterns of molecular epidemiology has been observed by this newly described assay., (Copyright © 2023 The Authors. Published by Tehran University of Medical Sciences.)

Escherichia coli sequence type 131 (ST131) is a pandemic clone associated with multidrug-resistant, extraintestinal infections, attributable to the presence of the CTX-M-15 extended-spectrum β-lactamase gene and mutations entailing fluoroquinolone resistance. Studies on subclones within E. coli ST131 are critically required for targeting and implementation of successful control efforts. Our study comprehensively analyzed the genomic and functional attributes of the H30-Rx subclonal strains NA097 and NA114, belonging to the ST131 lineage. We carried out whole-genome sequencing, comparative analysis, phenotypic virulence assays, and profiling of the antibacterial responses of THP1 cells infected with these subclones. Phylogenomic analysis suggested that the strains were clonal in nature and confined entirely to a single clade. Comparative genomic analysis revealed that the virulence and resistance repertoires were comparable among the H30-Rx ST131 strains except for the commensal ST131 strain SE15. Similarly, seven phage-specific regions were found to be strongly associated with the H30-Rx strains but were largely absent in the genome of SE15. Phenotypic analysis confirmed the virulence and resistance similarities between the two strains. However, NA097 was found to be more robust than NA114 in terms of virulence gene carriage (dra operon), invasion ability (P < 0.05), and antimicrobial resistance (streptomycin resistance). RT(2) gene expression profiling revealed generic upregulation of key proinflammatory responses in THP1 cells, irrespective of ST131 lineage status. In conclusion, our study provides comprehensive, genome-inferred insights into the biology and immunological properties of ST131 strains and suggests clonal diversification of genomic and phenotypic features within the H30-Rx subclone of E. coli ST131., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)

Diagnosing extra-pulmonary tuberculosis is a challenge that can confound even the most practiced clinicians as clinical manifestations are vague, non-specific and typical chest radiograph findings may not be evident till late in the disease. Conventional methods for mycobacteriological culture and drug susceptibility testing are slow and cumbersome. Novel technologies for rapid detection of Mycobacterium tuberculosis and its anti-TB drug resistance have therefore become a priority hence with the development of molecular line probe assays are most advanced. Herewith we are reporting a case of splenic tuberculosis in an immunocompromised patient for its rarity and to emphasis the fact that such patients can be diagnosed early for better treatment outcome to enhance the longevity if a health setup possesses all the modern diagnostic services.