Green Synthesis of Copper Oxide Nanoparticles from the Leaves of Aegle marmelos and Their Antimicrobial Activity and Photocatalytic Activities.

The leaves of the Aegle marmelos plant were used for the green synthesis of copper oxide nanoparticles and further characterized by different techniques, including (Ultra Violet-Visible) UV-Vis, Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX), Transmission electron microscopy (TEM) and X-ray diffraction (XRD). The UV-Vis showed a peak at 330 nm, which may be due to the Surface Plasmon Resonance phenomenon. XRD analysis showed the crystalline nature of copper oxide nanoparticles (CuO NPs). In contrast, SEM showed that nanoparticles were not aggregated or clumped, EDX showed the presence of elemental copper., and further, the TEM analysis revealed the average particle size of copper oxide nanoparticles to be 32 nm. The Minimum Inhibitory Concentration (MIC) for Escherichia coli (E. coli) and Staphylococcusaureus (S. aureus) was found to be 400 µg/mL, whereas for Candida albicans (C. albicans) and Candida dubliniensis (C. dubliniensis) it was 800 µg/mL. The zone of inhibition in the well diffusion assay showed the antimicrobial activity of copper oxide nanoparticles, and it also showed that as the concentration of copper oxide nanoparticles increased, the zone of inhibition also increased. Further, the electron microscopic view of the interaction between copper oxide nanoparticles and C. albicans cells showed that CuO NPs were internalized and attached to the cell membrane, which caused changes in the cellular structure and caused deformities which eventually led to cell death. The prepared CuO NPs showed significant photocatalytic degradation of organic dyes in the presence of sunlight.

Insight into the seroepidemiology and dynamics of circulating serotypes of dengue virus over a 4 year period in western Uttar Pradesh, India.

An important public health problem in India is dengue infection, with every year seeing an increase in cases of dengue fever. Dengue affects all individuals irrespective of their gender and age, although the infection rate is higher among males and younger people. Despite low severity in general, dengue virus can cause severe health conditions in some individuals. Genetic characterization of circulating endemic dengue virus (DENV) serotypes plays a significant role in providing epidemiological knowledge and subsequent vaccine development. In the present study, over a 4 year period, we assessed DENV transmission dynamics in major regions of western Uttar Pradesh in North India. ELISA tests were used to diagnose dengue, and PCRs were used to determine the circulating serotype. We found that dengue infection peaks after the rainy season and affects all sexes and ages. A total of 1277 individuals were found positive for dengue; among them, 61.7 % were male and 38.3 % were female. DEN-1 was found in 23.12 %, DEN-2 in 45 %, DEN-3 in 29.06 % and DEN-4 in 1.5 % of the dengue-infected individuals. All four DENV serotypes were circulating in the study area, and DENV serotype-2 (DEN-2) was the most prevalent serotype.

Biosynthesis of Gold Nanoparticles and Its Effect against Pseudomonas aeruginosa.

Antimicrobial resistance has posed a serious health concern worldwide, which is mainly due to the excessive use of antibiotics. In this study, gold nanoparticles synthesized from the plant Tinospora cordifolia were used against multidrug-resistant Pseudomonas aeruginosa. The active components involved in the reduction and stabilization of gold nanoparticles were revealed by gas chromatography-mass spectrophotometry(GC-MS) of the stem extract of Tinospora cordifolia. Gold nanoparticles (TG-AuNPs) were effective against P. aeruginosa at different concentrations (50,100, and 150 µg/mL). TG-AuNPs effectively reduced the pyocyanin level by 63.1% in PAO1 and by 68.7% in clinical isolates at 150 µg/mL; similarly, swarming and swimming motilities decreased by 53.1% and 53.8% for PAO1 and 66.6% and 52.8% in clinical isolates, respectively. Biofilm production was also reduced, and at a maximum concentration of 150 µg/mL of TG-AuNPs a 59.09% reduction inPAO1 and 64.7% reduction in clinical isolates were observed. Lower concentrations of TG-AuNPs (100 and 50 µg/mL) also reduced the pyocyanin, biofilm, swarming, and swimming. Phenotypically, the downregulation of exopolysaccharide secretion from P. aeruginosa due to TG-AuNPs was observed on Congo red agar plates.

Green Synthesis of Silver Nanoparticles from Camellia sinensis and Its Antimicrobial and Antibiofilm Effect against Clinical Isolates.

The green synthesis method of was used for the synthesis of silver nanoparticles using Camellia sinensis (green tea). The Camellia sinensis silver nanoparticles (CS-AgNPs) were characterized using different techniques, including UV-Vis (ultra violet-visible), SEM (scanning electron microscopy), TEM (transmission electron microscopy), and XRD (X-ray diffraction). The average size of the CS-AgNPs was 52 nm, according to TEM. The CS-AgNPs showed excellent antibacterial and antifungal activity. The MIC (minimum inhibitory concentration) against bacterial isolates varied from 31.25 to 62.5 µg/mL, whereas for fungal isolates, the MIC varied from 125 to 250 µg/mL. The presence of a zone in the well diffusion assay showed the antimicrobial nature of CS-AgNPs. Further, CLSM (confocal laser scanning microscopy) showed that CS-AgNPs possess antibiofilm activity. The interaction of CS-AgNPs with the Candidal cells was analyzed using TEM, and it was revealed that CS-AgNPs entered the cell and disrupted the cell machinery.

Comparing the profile of respiratory fungal pathogens amongst immunocompetent and immunocompromised hosts, their susceptibility pattern and correlation of various opportunistic respiratory fungal infections and their progression in relation to the CD4+T-cell counts.

INTRODUCTION: Invasive fungal infections are increasingly common in the nosocomial setting. MATERIALS AND METHODS: The patients were divided into two groups immunocompetent and immunocompromised that is, patients with significant neutropenia <500 neutrophils/µl for longer than 10 days. microscopy, culture, identification of isolates were done and some specilised tests on serum and BAL for antigen detection were performed. RESULTS: Majority of the patients were young adult males in this study. A higher prevalence of 26.7% was seen in immunocompromised patients. Amongst yeasts, Candida albicans was the predominant species followed by the National AIDS Control that is, Candida glabrata, Candida dubliniensis, Candida parapsilosis and Candida tropicalis in the same order. Amongst moulds, Aspergillus fumigatus was the most common species followed by Aspergillus flavus and Aspergillus niger. Mucor and Penicillium marneffei were seen in a lower prevalence. By Broth microdilution method, isolates of Candida spp. were most sensitive to caspofungin, amphotericin B, ketoconazole and fluconazole in the same order. Isolates of Aspergillus spp. were most sensitive to caspofungin, amphotericin B and itraconazole in the same order. By disc diffusion method, resistance to fluconazole was observed in 6.9% isolates of C. albicans. 50% of C. dubliniensis and 20% of C. glabrata showed resistance to fluconazole. A total mortality of 27.7% was observed during this study. This was distributed as 24.1%, 26.7%, 50%, 50%, 100% and 0% among by patients of candidiasis, aspergillosis, cryptococcosis, pneumocystosis, mucormycosis and penicilliosis. Fifteen per cent were lost to follow-up. CONCLUSION: Patterns of invasive fungal infections are changing in many ways. In the midst of these evolving trends, IFI of the respiratory tractcontinue to remain important causes of morbidity and mortality. Diagnostic tools can be adequately used only if the treating physician is aware of the propensity of patients to acquire a fungal infection. Thus, continuous awareness and education is crucial for successful management of patients. Judicious use of antifungal medications as prophylactic measures must be employed, particularly in the critically ill and patients of HIV.

Preconcentration and speciation of arsenic by using a graphene oxide nanoconstruct functionalized with a hyperbranched polyethyleneimine.

A column sorbent for arsenic was obtained through immobilization of highly branched polyethylenimine (PEI) on graphene oxide (GO). The composite material enables speciation of arsenic by tuning the pH of the sample solution which governs the surface charge of the sorbent, depending on whether amino groups (-NH2) are present (at high pH) or ammonium groups (-NH3+; at low pH). The composite can be applied to improved speciation of arsenic (compared to unmodified GO). There is no need for oxidation or reduction of arsenic. A column procedure was applied for the sequestered extraction and speciation of As(III) and As(V) from environmental water samples before their determination by hydride generation-microwave induced plasma-atomic emission spectrometry. The method has a preconcentration factor of 440 for As(III) and of 400 for As(V). The limits of detection (at 3 S/N) are extremely low, being 1.8 ± 0.2 ngL-1 for As(III) and 1.3 ± 0.08 ngL-1 for As(V). This is much lower than the arsenic guideline value of 10 µgL-1 as given by the WHO. Graphical abstract Graphene oxide interconnected with polyethyleneimine has been employed for the speciation and determination of arsenic. Quantitation by atomic emission spectroscopy reveals a high preconcentration factor (440 and 400) and low LODs of 1.8 ± 0.2 and 1.3 ± 0.08 ngL-1for As(III) and As(V), respectively.

Comparison of four diagnostic techniques for detection of Trichomonas vaginalis infection in females attending tertiary care hospital of North India.

BACKGROUND: Trichomonas vaginalis causes a common sexually transmitted disease trichomoniasis, which may lead to increased risk of transmission of human immunodeficiency virus infection and other pelvic inflammatory diseases. Wet mount examination is the most common test for diagnosis, but it has low sensitivity. Acridine orange staining can be used for diagnosis, but it requires special microscopic facility. Culture is considered as the gold standard, but it takes a long time for diagnosis. OSOM Trichomonas Rapid Test is a recently introduced rapid method based on immunochromatographic assay of trichomonal protein antigens. Hence, the present study was done to compare these four diagnostic techniques for detection of trichomoniasis in females with vaginal discharge. MATERIALS AND METHODS: Vaginal swabs were taken from 835 female patients and wet mount examination, acridine orange staining, culture in Kupferberg medium, and OSOM Trichomonas Rapid Test, were performed. RESULTS: Out of 835 patients included in our study, 68 (8.1%) positive cases of trichomoniasis were detected by culture. OSOM Trichomonas Rapid Test detected 63 (7.5%) cases, acridine orange staining detected 53 (6.3%) cases, whereas, wet mount examination detected only 45 (5.4%) positive cases. OSOM Trichomonas Rapid Test performed well and showed high sensitivity and specificity of 88.2% and 99.6%, respectively. CONCLUSION: As OSOM Trichomonas Rapid Test is a point of care test and gave better results than both wet mount examination and acridine orange staining; it can be used as a routine test in peripheral areas lacking laboratory facilities.

Gum arabic capped-silver nanoparticles inhibit biofilm formation by multi-drug resistant strains of Pseudomonas aeruginosa.

Clinical isolates (n = 55) of Pseudomonas aeruginosa were screened for the extended spectrum ß-lactamases and metallo-ß-lactamases activities and biofilm forming capability. The aim of the study was to demonstrate the antibiofilm efficacy of gum arabic capped-silver nanoparticles (GA-AgNPs) against the multi-drug resistant (MDR) biofilm forming P. aeruginosa. The GA-AgNPs were characterized by UV-spectroscopy, X-ray diffraction, and high resolution-transmission electron microscopy analysis. The isolates were screened for their biofilm forming ability, using the Congo red agar, tube method and tissue culture plate assays. The biofilm forming ability was further validated and its inhibition by GA-AgNPs was demonstrated by performing the scanning electron microscopy (SEM) and confocal laser scanning microscopy. SEM analysis of GA-AgNPs treated bacteria revealed severely deformed and damaged cells. Double fluorescent staining with propidium iodide and concanavalin A-fluorescein isothiocyanate concurrently detected the bacterial cells and exopolysaccharides (EPS) matrix. The CLSM results exhibited the GA-AgNPs concentration dependent inhibition of bacterial growth and EPS matrix of the biofilm colonizers on the surface of plastic catheters. Treatment of catheters with GA-AgNPs at 50 µg ml(-1) has resulted in 95% inhibition of bacterial colonization. This study elucidated the significance of GA-AgNPs, as the next generation antimicrobials, in protection against the biofilm mediated infections caused by MDR P. aeruginosa. It is suggested that application of GA-AgNPs, as a surface coating material for dispensing antibacterial attributes to surgical implants and implements, could be a viable approach for controlling MDR pathogens after adequate validations in clinical settings.

Interaction of silver nanoparticles with Escherichia coli and their cell envelope biomolecules.

The antibacterial effect of AgNPs was investigated by determining MIC/MBC and growth kinetics assay. The lowest MIC/MBC was found to be in the range of 11.25-22.5 µg ml(-1) . The growth kinetics curve shows that 25 µg ml(-1) AgNPs strongly inhibits the bacterial growth. Confocal laser scanning electron microscopy (CLSM) shows that as the concentration of NPs increases, reduction in the number of cells was observed and at 50 µg ml(-1) of NPs, 100% death was noticed. Scanning electron microscopy (SEM) shows cells were severely damaged with pits, multiple depressions, and indentation on cell surface and original rod shape has swollen into bigger size. High resolution-transmission electron microscopic (HR-TEM) micrograph shows that cells were severely ruptured. The damaged cells showed either localized or complete separation of the cell membrane. The NPs that anchor onto cell surface and penetrating the cells may cause membrane damage, which could result in cell lysis. The interaction of AgNPs to membrane biomolecules; lipopolysaccharide (LPS) and L-α-phosphatidyl-ethanolamine (PE) were investigated by attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectroscopy. LPS and PE showed IR spectral changes after AgNPs exposure. The O-antigen part of LPS was responsible for interaction of NPs through hydrogen bonding. The phosphodiester bond of PE was broken by AgNPs, forming phosphate monoesters and resulting in the highly disordered alkyl chain. The AgNPs-induced structural changes in phospholipid may lead to the loss of amphiphilic properties, destruction of the membrane and cell leaking. The biomolecular changes in bacterial cell envelope revealed by ATR-FTIR provide a deeper understanding of cytotoxicity of AgNPs.

Evaluation of Different Staining Techniques in the Diagnosis of Trichomonas vaginalis Infection in Females of Reproductive Age Group.

BACKGROUND: Trichomonas vaginalis is a parasitic protozoan which causes most common non viral sexually transmitted disease trichomoniasis. Direct microscopic examination of vaginal fluid remains the most widely used diagnostic test. Although, wet mount examination is the most cost-effective diagnostic test, but it has low sensitivity resulting in under diagnosis of the disease. Therefore, to overcome this problem, various staining techniques like giemsa and acridine orange can be used along with wet mount examination for diagnosis of T. vaginalis infection. OBJECTIVE: The present study was done to evaluate the efficacy of Giemsa and Acridine Orange staining in comparison with wet mount examination for the diagnosis of vaginal trichomoniasis. MATERIALS AND METHODS: A total of 615 female patients of reproductive age group having vaginal discharge were included in the study and swabs containing vaginal fluids were taken to perform wet mount examination, giemsa staining and acridine orange staining. RESULT: Trichomonas vaginalis infection was detected in 37 patients with maximum cases (6.0%) detected by acridine orange staining, followed by giemsa staining (4.9%), whereas, wet mount examination was able to detect only 4.1% cases. Wet mount examination gave a sensitivity of 67.6%, whereas, the sensitivity of giemsa staining and acridine orange staining was found to be 80% and 100% respectively. CONCLUSION: Since the performance of both the staining techniques was found to be much better in comparison to wet mount examination, and they also detected several wet mount negative cases, they should be used as an adjunct to wet mount examination. This will also be beneficial to the overall health of the patient by early diagnosis and treatment of cases, thereby, reducing the development of associated morbidity.

bla(CTX-M), bla(TEM), and bla(SHV) in Enterobacteriaceae from North-Indian tertiary hospital: high occurrence of combination genes.

OBJECTIVE: To delineate the frequency of occurrence of bla(CTX-M), bla(TEM), and bla(SHV) in Enterobacteriaceae from North-Indian tertiary hospital. METHODS: A random collection of a subset of 45 Escherichia coli (E. coli) and 28 Klebsiella pneumoniae (K. pneumoniae) that was resistant to a third generation cephalosporin and obtained during 2007-2008 was selected for detailed screening for bla(CTX-M), bla(TEM), and bla(SHV) by monoplex PCRs. The isolates demonstrating the presence of bla(CTX-M) alleles were characterized for the specific CTX-M-genogroup by using a multiplex PCR. RESULTS: Resistance to cefoperazone, ceftazidime, ceftriaxone, cefotaxime, cefoxitin and piperacillin was 100% each in K. pneumoniae isolates, whereas these resistance-rates for E. coli isolates were 93.1%, 83.8%, 91.9%, 93.6%, 97.3% and 97.1%, respectively. Concomitant resistance to aminoglycosides, quinolones and aztreonam was also noticed. Presence of any of the bla genes (bla(CTX-M), bla(TEM), and bla(SHV)) was noticed in a total of 28 (38.4%) isolates of the 73 isolates studied. Many isolates demonstrated occurrence of these genes in various combinations. bla(CTX-M), bla(TEM), and bla(SHV) were noticed in 28.8%, 10.9% and 13.7% isolates, respectively. Multiplex PCR in bla(CTX-M) harboring isolates demonstrated the presence of CTX-M-Genogroup-1 and sequencing for the specific CTX-M-type revealed presence of CTX-M-15 type. RAPD typing showed wide diversity in isolates. CONCLUSIONS: This is amongst the premier report describing the simultaneous occurrence of bla(TEM), bla(SHV), and bla(ampC) in Indian Enterobacteriaceae and that wider dissemination of these genes, as demonstrated by diversity of isolates, raises concern and emphasizes a need for extensive search for the presence of these gene pools in Indian subcontinent.