NaBiF4:Yb3+,Tm3+ submicron particles as luminescent probes for in vitro imaging of cells.

Upconversion materials have attracted considerable research interest for their application in bioimaging due to their unique optical properties. NaREF4 (RE = Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) based host lattice, which is widely used for upconversion, requires expensive rare-earth elements and tedious reaction conditions. Hence there is a need to develop environmentally friendly and cost effective materials for upconversion. In this study, we propose NaBiF4 as a host material for upconversion which is based on environmentally friendly and cost-effective bismuth. NaBiF4 has not been explored as an imaging probe before. We report efficient Yb3+/Tm3+ doped NaBiF4 based upconversion submicron particles which exhibit a photostable, wide upconversion emission range (NIR-to-NIR and Vis) under NIR (980 nm) excitation, and in-vitro non-cytotoxic uptake by mammalian cancer cell lines as well as bacterial cells with a high signal to background ratio. The synthesis of the chosen host material co-doped with Yb3+/Tm3+ has not been reported earlier through such a non-aqueous quaternary reverse micelle route. Here, we functionally validate these submicron particles as viable alternatives to currently available upconversion nanomaterials and highlight their potential as luminescent probes for bioimaging.

Prevalence of S. aureus and/or MRSA from seafood products from Indian seafood products.

Compared to the clinical sector, the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in the food sector is relatively low. However, their presence in seafood is a significant public health concern. In India, fish and fishery products are maximally manually handled compared to other food products. In this study, 498 fish samples were collected under various conditions (fresh, chilled or dressed) and representatives from their surroundings. These samples were screened for the prevalence of Staphylococcus aureus, determining its antimicrobial resistance, MRSA and genetic profile. It is observed that 15.0% and 3.0% of the total samples were screened positive for S. aureus and MRSA, respectively. The S. aureus strain MRSARF-10 showed higher resistance to linezolid, co-trimoxazole, cefoxitin, ofloxacin, gentamicin, rifampicin, ampicillin/sulbactam and Piperacillin-tazobactam. This MRSA, spa type t021 and SCCmec type V strain isolated from dried ribbon fish (Family Trachipteridae) carried virulence factors for exoenzymes such as aureolysin, serine, toxin genes and a novel MLST ST 243, as revealed from its draft-genome sequence. This highly pathogenic, multidrug-resistant and virulent S. aureus novel strain is circulating in the environment with chances of spreading among the seafood workers and the environment. It is further suggested that Good Hygienic Practices recommended by World Health Organization need to be followed during the different stages of seafood processing to provide pathogen-free fish and fishery products to the consumers.

Detection of parvovirus B19 in selected high-risk patient groups & their phylogenetic & selection analysis.

Background & objectives: Human parvovirus B19V (B19V) is known to be associated with erythema infectiosum commonly in children, aplastic crisis, especially in persons with underlying haemolytic disorders, hydrops fetalis in pregnancies and arthritis. This cross-sectional study was aimed to determine the presence of B19V infection in childhood febrile illnesses, association of B19V with arthropathies and in adult patients with end-stage renal disease (ESRD) on dialysis. The genetic diversity among the sequences was also analysed. Methods: A nested polymerase chain reaction (nPCR) assay was used for B19V DNA targeting VP1/VP2 region and used for testing 618 patients and 100 healthy controls. Phylogenetic analysis on nucleotide and amino acid sequences was carried out to compare our sequences with other Indian strains and global strains. Results: Among 618 samples tested, seven (1.13%) were found positive. The phylogenetic analysis revealed that all the seven sequences belonged to genotype 1 and showed low genetic diversity. The clustering pattern of seven sequences was similar both by nucleotide and by predicted amino acid sequences. The fixed effects likelihood analysis showed no positive or negatively selected sites. Interpretation & conclusions: Seven samples (4 from non-traumatic arthropathies, 2 from patients with ESRD and 1 from febrile illness patient) were found positive by nPCR. When our seven sequences were compared with global strains, the closest neighbour was other Indian strains followed by the Tunisian strains.

CT morphology and morphometry of the normal adult coccyx.

PURPOSE: Lack of data on the in vivo morphology and morphometry of the normal adult coccyx hampers understanding of radiological abnormalities in idiopathic coccydynia. The aim of this study was to investigate normal adult sacrococcygeal morphometry. METHODS: Retrospective analysis of 112 adult CT scans (mean age 63 ± 14.6 years, 50 males) evaluated the following: number of coccygeal segments; joint fusion; coccygeal spicules, subluxation, sacralization, and scoliosis; sacrococcygeal straight and curved lengths and curvature indices; sacrococcygeal and intercoccygeal angles; and lateral deviation of the coccyx tip. RESULTS: Four coccygeal segments were present in 76 % of scans. Sacrococcygeal fusion was present in 57 % and intercoccygeal fusion was increasingly common more caudally; there was no significant association with age or gender. A bony spicule was present in 23 %. Subluxation was rare. Nine of 12 coccyges with a retroverted tip were female. Mean coccygeal curved length was 4.4 ± 0.8 cm in men and 4.0 ± 0.8 cm in women (P < 0.01). Mean angle between first and last coccygeal segments was 138° ± 25° in men and 147° ± 25° in women (P = 0.08). There was no significant correlation between coccygeal length or curvature and stature, age or BMI. CONCLUSIONS: In this first detailed study of the CT morphology and morphometry of the adult coccyx, sacrococcygeal and intercoccygeal joint fusion was common. Female coccyges were shorter, straighter, and may be more prone to retroversion, factors that may be relevant to the markedly higher prevalence of idiopathic coccydynia in women.

Size fraction of hazardous particulate matter governing the respiratory deposition and inhalation risk in the highly polluted city Delhi.

Delhi has been identified as one of the highly polluted cities in the world and recently associated with the highest population weighted PM2.5 concentration. However, the unavailability of the health risk estimations using long-term data for Indian cities has been pointed out as a hurdle in performing the correct assessment. The present work estimated deposition of particles in different regions of respiratory systems (head airway = 67% deposition for 2.5 µm particles; tracheo-bronchiolar (TB) = 73% deposition for 1.0 µm particles; alveolar (AL) = 17% deposition for 0.5 µm, 0.25 µm, and < 0.25 µm particles) using PM samples collected at a breathing height of 1.5 m near the major ring road in New Delhi (India). The calculated risk index (RI) varied considerably between winter (1.21 ± 0.26 to 1.33 ± 0.50) and pre-monsoon-southwest monsoon months (0.34 ± 0.08 to 0.96 ± 0.27). Respiratory deposition dose of nanosized particles (≤ 500 nm) in the alveoli region of the lung was found to be considerable (35%) indicating the need for understanding the role of these particles in posing health risk. Although the calculated values of risk metric for exposures of PM-associated metals indicated no risk to IIT Delhi population (hazard quotient < 1 and excess risk of getting cancer < 10-6-10-9), continuous monitoring for particles of different sizes at inhalation height are required for protecting human health.

SERS Nanowire Chip and Machine Learning-Enabled Classification of Wild-Type and Antibiotic-Resistant Bacteria at Species and Strain Levels.

Antimicrobial resistance (AMR) is a major health threat worldwide and the culture-based bacterial detection methods are slow. Surface-enhanced Raman spectroscopy (SERS) can be used to identify target analytes in real time with sensitivity down to the single-molecule level, providing a promising solution for the culture-free bacterial detection. We report the fabrication of SERS substrates having tightly packed silver (Ag) nanoparticles loaded onto long silicon nanowires (Si NWs) grown by the metal-assisted chemical etching (MACE) method for the detection of bacteria. The optimized SERS chips exhibited sensitivity down to 10-12 M concentration of R6G molecules and detected reproducible Raman spectra of bacteria down to a concentration of 100 colony forming units (CFU)/mL, which is a thousand times lower than the clinical threshold of bacterial infections like UTI (105 CFU/mL). A Siamese neural network model was used to classify SERS spectra from bacteria specimens. The trained model identified 12 different bacterial species, including those which are causative agents for tuberculosis and urinary tract infection (UTI). Next, the SERS chips and another Siamese neural network model were used to differentiate AMR strains from susceptible strains of Escherichia coli (E. coli). The enhancement offered by SERS chip-enabled acquisitions of Raman spectra of bacteria directly in the synthetic urine by spiking the sample with only 103 CFU/mL E. coli. Thus, the present study lays the ground for the identification and quantification of bacteria on SERS chips, thereby offering a potential future use for rapid, reproducible, label-free, and low limit detection of clinical pathogens.

Estimating seasonal variations of realistic exposure doses and risks to organs due to ambient particulate matter -bound metals of Delhi.

This study aims to calculate deposition of PM2.5 -bound hazardous metals in different organs after inhalation of particulate matter for the Delhi (India), and to estimate risks to organs following inhalation. Bio-accessible fractions of three PM-associated carcinogenic metals (As, Pb &Cd) were calculated using the metal values in simulated lung fluids. Depositions of metals in different organs were calculated using an integrated model consists of HRT and PBPK models. The calculation indicates that the major or significant deposition of metal Pb occurs in tissues, such as bone, muscle and blood. Most of the depositions of Cd happens in lung whereas most of the depositions of As happens in lung, muscle and skin. Most of the deposition of studied metals was found in lung (45% for arsenic and 70% for cadmium of their bio -dissolved contents). The following order of depositions of metals in different tissues were found (from highest deposition to smallest deposition): As: Lung > muscle = liver; Pb: bone > blood > muscle; Cd: lung > intestine. The combined exposures of PM2.5 and its associated metals were found to give interaction-based hazard index greater than 1 for several months of the year, indicating a chance of health risk. Hazard quotient (HQ) <1 was seen for ingestion and dermal pathways, indicating no cause of concern. Findings indicate the need for doing periodic monitoring and estimating deposition doses and exposure risks of PM-associated metals to lungs and other organs for protecting human health.

Hepatitis C and hepatitis B nucleic acids are present in intrahepatic cholangiocarcinomas from the United States.

Intrahepatic cholangiocarcinomas (IHCs) are rare in the United States, but the prevalence is steadily increasing and risk factors are poorly understood. Tissues were obtained at the time of surgical resection, and 11 cases of IHC were retrospectively studied for the presence of hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA. Hemi-nested and real-time polymerase chain reaction assays were used to detect HBV DNA, and nested reverse transcriptase-polymerase chain reaction was used to detect HCV RNA. Genotypes were determined for both HBV and HCV. The cases were predominantly from women (10/11), with an average age at surgery of 63 years and an average tumor size of 6 cm. Three cases (27%) were positive for either HBV or HCV nucleic acids: HBV alone (n = 1), HCV alone (1), coinfection with HBV and HCV (1). Both HBV-positive cases were genotype A, and both HCV cases were genotype 1a. Hepatitis B and C viral copy numbers were low in all cases. Evidence for active HBV replication was found in both HBV-positive cases, as they were positive for covalently closed circular DNA. In this study, 27% of ICC cases contained HBV and/or HCV nucleic acids, suggesting an etiologic role for these viruses in some cases of IHC.

Glycated serum albumin stimulates expression of endothelial cell specific molecule-1 in human umbilical vein endothelial cells: Implication in diabetes mediated endothelial dysfunction.

Pro-inflammatory conditions induced by products of protein glycation in diabetes substantially enhance the risk of endothelial dysfunction and related vascular complications. Endothelial cell specific molecule-1 (ESM-1) or endocan has been demonstrated as a potential biomarker in cancer and sepsis. Its role in diabetes-induced pathologies remains unknown. The expression of ESM-1 gene is under cytokine regulation, indicating its role in endothelium-dependent pathological disorders. In this study, we investigated the effect of advanced glycated human serum albumin (AGE-HSA) on the production of ESM-1. We show that AGE-HSA exerts a modulating role on the expression of ESM-1 in human umbilical vein endothelial cells. It up-regulates expression of ESM-1 protein in a dose-dependent manner which correlates with its messenger RNA (mRNA) transcription. RAGE and galectin-3, both AGE receptors, show antagonistic action on its expression. While gene silencing of RAGE has down-regulatory effect, that of galectin-3 has up-regulatory effect on AGE-induced expression of ESM-1. Inhibition of MAPKKK and JNK pathways did not alter the expression. In contrast, phosphatidylinositol 3 kinase (PI3K) inhibition significantly up-regulated ESM-1 expression. In conclusion, these results suggest that AGE-induced activation of human umbilical vein endothelial cells promotes formation of endocan which is an endothelial dysfunction marker and may be related to vascular disease in diabetes.

In vitro control release, cytotoxicity assessment and cellular uptake of methotrexate loaded liquid-crystalline folate nanocarrier.

Folate molecules self-assemble in the form of stacks to form liquid-crystalline solutions. Nanocarriers from self-assembled folates are composed of highly ordered structures, which offer high encapsulation of drug (95-98%), controlled drug release rates, active cellular uptake and biocompatibility. Recently, we have shown that the release rates of methotrexate can be controlled by varying the size of nanoparticles, cross-linking cation and cross-linking concentration. The present study reports the in vitro cytotoxic behavior of methotrexate loaded liquid-crystalline folate nanoparticles on cultured HeLa cells. Changing drug release rates can influence cytotoxicity of cancer cells. Therefore, to study the correlation of release rate and cytotoxic behavior, the effect of release controlling parameters on HeLa cells was studied through MTT assay. It is reported that by controlling the methotrexate release, the survival rates of HeLa cells can be controlled. Released methotrexate kills HeLa cells as effectively as free methotrexate solution. The co-culture based in vitro cellular uptake study through fluorescence microscopy on folate receptor positive and negative cancer cells shows that the present nanocarrier has the potential to distinguish cancer cells from normal cells. Overall, the present study reports the in vitro performance of self-assembled liquid-crystalline folate nanoparticles, which will be a platform for further in vivo studies and clinical trials.

Magnetic resonance imaging morphology and morphometry of the coccyx in coccydynia.

STUDY DESIGN: Retrospective case-control study. OBJECTIVE: To determine if differences exists between the bony anatomy of the coccyx in patients with coccydynia and that in subjects with no known coccygeal pathology. SUMMARY OF BACKGROUND DATA: Numerous bony characteristics of the coccyx have been described in patients with coccydynia but their significance is uncertain. This study aimed to evaluate these in patients with coccydynia and compare them with normal coccyges. METHODS: Magnetic resonance scans of the coccyx from 107 adults (mean age, 43 ± 12 yr; 84 females) with clinically diagnosed coccydynia were retrospectively analyzed and compared with 112 computed tomographic scans from sex-matched adults with normal coccyges. The following were assessed: coccygeal segmentation; sacrococcygeal and intercoccygeal joint fusion, angles, and curvature; bony spicule formation; and subluxation. RESULTS: Compared with normal, females with coccydynia had a more ventrally curved coccyx (curvature index, 85 ± 7 vs. 90 ± 5; P< 0.01), a lower prevalence of sacrococcygeal joint fusion (27% vs. 58%, P< 0.01), and a higher frequency of bony spicule formation (44% vs. 19%, P< 0.01). Males with coccydynia showed a trend toward a more ventrally curved coccyx (curvature index: 86 ± 6 vs. 89 ± 5, P< 0.08), and a lower prevalence of sacrococcygeal (27% vs. 60%, P< 0.02) and intercoccygeal (0% vs. 22%, P< 0.02) joint fusion. Combining statistically significant coccygeal parameters in a logistic regression model yielded sensitivity, specificity, and positive predictive values of 72%, 71%, and 73%, respectively in females and 52%, 92%, and 73%, respectively in males. CONCLUSION: This is the most detailed comparison of coccygeal morphology and morphometry in adults with and without coccydynia investigated using cross-sectional imaging. Anatomical differences in joint fusion and coccygeal curvature may either predispose to the development of coccydynia or arise as a result of this condition.