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The type of packaging used for food products is an essential component in the extension of their shelf life, their quality and nutritional value, and their protection from contaminants, moisture, and bacteria. Because of the emergence of drug-resistant pathogenic strains, food packaging is increasingly important in protecting consumers from diseases. Moreover, the food industry has grown exponentially overtime and has suffered huge economic losses and contributed to loss of life due to food spoilage and foodborne pathogens. Novel packaging technologies are being explored that hold the potential to develop more eco-friendly, more economic, safer, and longer storage characteristics. The research and industrial sectors are focusing strongly on ways to enhance consumer safety through sustainable and smart packaging. Silver nanoparticles (AgNPs) have opened up new areas of research and are an important factor in the evolution of the global food packaging industry, and already a wide range of AgNPs have been examined in regard to minimizing both the risk of food spoilage and the effects of emerging foodborne pathogens. This chapter reviews a broad range of AgNPs as key antimicrobial components in smart and active packaging and also highlights AgNPs’ antimicrobial mechanisms and the current status and challenges related to nano‑silver-based packaging and the related regulations.

Subcutaneous zygomycosis is a rare fungal infection caused by Basidiobolus ranarum. This entity is usually endemic in South India and only limited numbers of cases have been reported from central India. We report a case of 4-year-old male child from Chhattisgarh, who presented with a painless, non-tender, large, subcutaneous swelling of 4 months duration on the right upper arm, which was initially misdiagnosed as benign spindle cell tumor and advised surgical resection. But the fungal culture of the affected tissue grown Basidiobolus ranarum and the child responded very well to itraconazole therapy only. Keywords: Basidiobolus ranarum, Subcutaneous zygomycosis, Fungal infection, Spindle cell tumor, Itraconazole therapy

A 30 years old, strictly vegetarian male presented with generalized weakness, weight loss, and gradually progressing cutaneous hyperpigmentation. On examination, pigmentation was more pronounced on sunexposed areas, flexural folds, and palmar creases along with mucosal involvement in the form of glossitis and pallor. Laboratory investigations revealed megaloblastic anaemia and low vitamin B12 level, thereby confirming the diagnosis of vitamin B12 deficiency. The treatment consisted of vitamin B12 supplementation. Vitamin B12 deficiency may occur due to malabsorption (due to pernicious anemia or gastric resection) and rarely, due to inadequate intake (almost exclusively in strict vegetarians). Cutaneous manifestations due to vitamin B12 deficiency manifest early and have diagnostic importance, thus allowing timely diagnosis and prevention of late neurological and other systemic complications.

Objective. The development of an accurate, sensitive, specific, rapid, reproducible, stable-at-room-temperature and cost-effective diagnostic kit, and a low-cost portable fluorescence detector to fulfil the requirements of diagnostic facilities in developing countries. Methods. We developed the ‘Chlamy and Ness CT/NG kit’ based on molecular beacons for the detection of Chlamydia trachomatis (CT) and Neisseriagonorrhoeae (NG). Multi-centric evaluation of the CT/NG kit was performed using the commercially available nucleic acid amplification test (NAAT)-based FTD Urethritis basic kit for comparison from December 2014 to November 2016. The stability of the kit reagents at 4 and 37 ˚C and the inter-day reproducibility of results were also analysed. Results. The sensitivity and specificity of the kit were found to be 95.83 and 100.00 % for the detection of C. trachomatis and 93.24 and 99.75 % for N. gonorrhoeae, respectively, when tested against the commercial kit. The positive predictive value (PPV) was 100.00 and 98.57 %, whereas the negative predictive value (NPV) was 99.54 and 98.79 % for C. trachomatis and N. gonorrhoeae, respectively. Analysis of the kappa statistics enhanced the ‘inter-rater’ κ=0.976 for Chlamydia and κ=0.943 for Neisseria. Conclusion. Our kit was found to be as sensitive and specific as commercially available kits. Its low cost and ease of use will make it suitable for the routine diagnosis of C. trachomatis and N. gonorrhoeae in the resource-limited settings of developing countries.

Cellular neurothekeoma is a rare cutaneous tumor that occurs more frequently in women. A 68-year-old female with a history of left nasal alar basal cell carcinoma and Guillain-Barré syndrome presented to the clinic with a 3-mm firm skin-colored papule with scattered telangiectasias. Histopathologic examination with immunochemistry of the lesion was consistent with cellular neurothekeoma. It stained positive for microphthalmia transcription factor and NKI-C3 and negative for HMB-45 and S-100. The lesion was excised with 3-mm margins, and no recurrence was noted within 1 year of follow-up. We present a case of cellular neurothekeoma in a patient with a history of Guillain-Barré syndrome as well as a review of the literature. Our case report is unique in that no prior association has been found in the literature between cellular neurothekeoma and Guillain-Barré syndrome. © 2014 S. Karger AG, Basel

Background Screening women for Chlamydia trachomatis infection in developing countries is highly desirable because of asymptomatic infection. The existing diagnostic methods in developing countries are not effective and their sensitivity fall below 45.0% which leads to further spread of infection. There is an urgent need for improved and cost effective diagnostic tests that will reduce the burden of sexually transmitted infections in the developing world. Methods Prevalence of C. trachomatis infection among women visiting gynaecology department of Hindu Rao hospital in Delhi, India was determined using Roche Amplicor Multi Well Plate kit (MWP) as well as using in-house PCR assay. We used 593 endocervical swabs for clinical evaluation of the in-house developed assay against Direct Fluorescence Assay (DFA; Group I n = 274) and Roche Amplicor MWP kit (Group II, n = 319 samples) and determined the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of the in-house developed assay. Results We detected 23.0% positive cases and there was a higher representation of women aged 18-33 in this group. An in-house PCR assay was developed and evaluated by targeting unique sequence within the gyrA gene of C. trachomatis. Specificity of the reaction was confirmed by using genomic DNA of human and other STI related microorganisms as template. Assay is highly sensitive and can detect as low as 10 fg of C. trachomatis DNA. The resolved sensitivity of in-house PCR was 94.5% compared with 88.0% of DFA assay. The high specificity (98.4%) and sensitivity (97.1%) of the in-house assay against Roche kit and availability of test results within 3 hours allowed for immediate treatment and reduced the risk of potential onward transmission. Conclusions The in-house PCR method is cost effective (~ 20.0% of Roche assay) and hence could be a better alternative for routine diagnosis of genital infection by C. trachomatis to facilitate improved screening and treatment management.

Introduction About 300 million new infections of gonorrhoea, Chlamydia, or trichomoniasis occur each year. Young adults, population with health inequities and people in resource poor settings bear the significant proportion of sexually transmitted infections (STI). Therefore, rapid, inexpensive and acceptable tests are needed to address STIs in developing countries. PCR based tests are recommended for diagnosis of several STIs, but such tests require sophisticated infrastructure, need to be imported and hence cannot be used in resource limited settings. Affordability can be countered by the development of in house diagnostic assays which are practical and easy to use, and produced within country to further lower the cost. Methods Endocervical swabs were collected from patients visiting gynaecology department of hospitals in Delhi. In-house PCR based assay was developed for C. trachomatis , N. gonorrhoeae and T. vaginalis and modified to visual assay using molecular beacon for end-point detection. Results The molecular beacon based PCR assay was developed for C. trachomatis , N. gonorrhoeae and T. vaginalis and evaluated against different commercial kits viz; Roche AMPLICOR NG/CT kit and qPCR kit of Abbott and fast-track diagnostics. Specificity of molecular beacon was confirmed by competition experiments. Diagnostic tests were more than 95% specific and 99.0% sensitive for all the three pathogens and negative and positive predicted values were around 98.5% and 97.5%, respectively at 95% CI for these three pathogens. We also observed that dry swab samples gave concordant results with that of wet swabs. Assay reagents were stable for more than 6 months at room temperature. We also report, high rates of co-infection for C. trachomatis + N. gonorrhoeae , C. trachomatis + T. vaginalis , N. gonorrhoeae + T. vaginalis amongst women patients in India. Conclusions Development of a rapid, sensitive, specific and PCR based visual diagnostic assay, suitable for developing countries will provide a better disease management.

Background Due to absence of cost effective and rapid diagnostic test syndromic management of Neisseria and Chlamydia was recommended in developing countries. Being nonspecific such a strategy has resulted in over treatment leading to increased drug resistance. It also misses out on asymptomatic patients resulting in increase in disease burden. The study describes the development and evaluation of a low cost duplex PCR method (dPCR) for co-detection of Neisseria and Chlamydia. Using molecular beacons we further provide a method for quantitative and easy detection of the two pathogens. Methods Endocervical swabs were collected from patients visiting gynaecology department of various hospitals in Delhi. We standardised and evaluated in-house uniplex PCR (uPCR) for diagnosis of Neisseria against Roche Amplicor Micro Well Plate CT/NG kit. Method was modified to co-detect N. gonorrhoeae and C. trachomatis in single test. Further we developed visual assay for detection of Chlamydia and Neisseria using molecular beacon probe. Results Clinical samples (n = 412) were used to validate in-house uPCR assay for Neisseria. The PPV and NPV were found to be 86.77% and 97.2%. We further modified our uPCR to dPCR for simultaneous detection of Neisseria and Chlamydia. The overall infection rate was found to be 27.8% and 26.3% for Neisseria and Chlamydia respectively while 11.3% of patients were co-infected. The in-house dPCR was found to be 85.7% sensitive and 97% specific. To further enhance the sensitivity and specificity of our test, molecular beacon were designed against the amplicons. Use of molecular beacons also reduced the detection time as amplicons could be directly visualised under dark reader. Conclusions The in-house dPCR assay is rapid and as sensitive as commercially available tests. Use of molecular beacons provides a highly specific and easy to use detection method, making it a better option for routine diagnosis of genital infection in developing countries.

Background Despite the recent advances in diagnosis, Neisseraia gonorrhoeae (NG) and Chlamydia trachomatis (CT) remain leading cause of STDs worldwide and account for STI9s morbidity leading to acquisition of HIV and HPV infection. Coinfection of gonococcus and Chlamydia is reported from various countries. In recent study we reported high rate of infection by CT using an in house developed PCR method. A number of studies also suggest increasing rate of antibiotic resistance in NG. Thus we developed a rapid, specific and cost effective diagnostic method to detect prevalence of co infection by NG and CT. Methodology: (1) Unique gene sequence of CT and NG were amplified from gDNA isolated from endocervical swabs. (2) Validation of in house PCR method using Roche AMPLICOR Micro well plate CT/NG kit. (3) Use of molecular beacon to develop easy visual method. (4) Establishment of multiplex PCR (mPCR) for simultaneous detection of CT and NG. Results 360 clinical samples were used to validate in house PCR assay. Discrepancy of the samples was resolved by amplifying genes encoding for outer membrane proteins (rmp for NG and ompA for CT). The resolved PPV and NPV were found to be 94% and 99% for CT, 92.0% and 96% for NG. Molecular beacon probe was used which helped in visualisation of PCR product directly in tube using dark reader which also improved the sensitivity of assay. The overall infection rate by NG was 26% and 8.6% in symptomatic and asymptomatic patients while that of CT was 26.3% and 21% respectively. To make the method easy to use in remote areas with minimum laboratory infrastructure, the in house PCR assay was standardised for detection using dry swabs, with crude DNA preparation and stabilisation of reagents at 4C (up to 6 months) was achieved for easy transportation and storage. Using single PCRs, coinfection by CT and NG was found to be 18% in symptomatic (74/410) and 5 % in asymptomatic patients (18/360). We further developed mPCR for simultaneous detection two pathogens. Sensitivity of in house mPCR was found to be 95% when evaluated against PCR for individual pathogen. Conclusion Detection of both the pathogens in single PCR assay makes it economical both in terms of cost and time. The in house assay is highly sensitive, easy to perform and requires minimum infrastructure as well as technical expertise, making it a better option for routine diagnosis of genital infection in developing countries, which would be of great consequences in disease management.