Insights into the genetic variability and evolutionary dynamics of tomato spotted wilt orthotospovirus in China.

BACKGROUND: Viral diseases are posing threat to annual production and quality of tobacco in China. Recently, tomato spotted wilt orthotospovirus (TSWV) has been reported to infect three major crops including tobacco. Current study was aimed to investigate the population dynamics and molecular diversity of the TSWV. In the current study, to assess and identify the prevalence and evolutionary history of TSWV in tobacco crops in China, full-length genome sequences of TSWV isolates from tobacco, were identified and analyzed. METHODS: After trimming and validation, sequences of new isolates were submitted to GenBank. We identified the full-length genomes of ten TSWV isolates, infecting tobacco plants from various regions of China. Besides these, six isolates were partially sequenced. Phylogenetic analysis was performed to assess the relativeness of newly identified sequences and corresponding sequences from GenBank. Recombination and population dynamics analysis was performed using RDP4, RAT, and statistical estimation. Reassortment analysis was performed using MegaX software. RESULTS: Phylogenetic analysis of 41 newly identified sequences, depicted that the majority of the Chinese isolates have separate placement in the tree. RDP4 software predicted that RNA M of newly reported isolate YNKM-2 had a recombinant region spanning from 3111 to 3811 bp. The indication of parental sequences (YNKMXD and YNHHKY) from newly identified isolates, revealed the conservation of local TSWV population. Genetic diversity and population dynamics analysis also support the same trend. RNA M was highlighted to be more capable of mutating or evolving as revealed by data obtained from RDP4, RAT, population dynamics, and phylogenetic analyses. Reassortment analysis revealed that it might have happened in L segment of TSWV isolate YNKMXD (reported herein). CONCLUSION: Taken together, this is the first detailed study revealing the pattern of TWSV genetic diversity, and population dynamics helping to better understand the ability of this pathogen to drastically reduce the tobacco production in China. Also, this is a valuable addition to the existing worldwide profile of TSWV, especially in China, where a few studies related to TSWV have been reported including only one complete genome of this virus isolated from tobacco plants.

Do high-mobility group box 1 gene polymorphisms affect the incidence of differentiation syndrome in acute promyelocytic leukemia?

BACKGROUND: Differentiation syndrome (DS) is an inflammatory complication seen in some patients with acute promyelocytic leukemia (APL) undergoing differentiation therapy with all-trans retinoic acid (ATRA) and/or arsenic trioxide (ATO). It is unknown how DS occurs, but it is believed that it is caused by inflammatory cytokines release from differentiating leukemic cells. High mobility group box-1 (HMGB1) is a DNA-binding protein that acts as a cytokine outside of cells and may play a role in inflammation. This study was conducted to determine whether HMGB1 polymorphisms (rs1360485, rs2249825 and rs1060348) are associated with the incidence of differentiation syndrome in acute promyelocytic leukemia patients treated with all-trans retinoic acid and arsenic trioxide. METHODS: One hundred and thirty APL patients and 100 healthy controls were included. Seventeen patients with differentiation syndrome were selected according to the PETHEMA criteria. Tetra-primer ARMS polymerase chain reaction (tetra-ARMS PCR) was used to determine the genotype distribution of polymorphisms. DNA sequencing was done to validate the results. RESULTS: In both healthy and APL patients, AA was the most frequent genotype in rs1360485 followed by AG and GG. CC, CG, and GG were the most frequent genotypes in rs2249825 polymorphism in the order mentioned. CC was more frequent than CT, and CT was more frequent than TT in rs1060348. There was no correlation between HMGB1 polymorphisms and the incidence of differentiation syndrome based on genetic models (p-value > 0.05). CONCLUSIONS: HMGB1 polymorphisms are not probably associated with DS development in APL patients treated with ATRA and ATO.

The impact of ICAM-1, CCL2 and TGM2 gene polymorphisms on differentiation syndrome in acute promyelocytic leukemia.

BACKGROUND: Although arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) are well-tolerated and effective treatments for Acute Promyelocytic Leukemia (APL), Differentiation Syndrome (DS) is a lethal side effect in some patients. The pathogenesis of DS is complex and not well understood; however, it is considered as an inflammatory response due to cytokines release of differentiated cells. Moreover, adhesion molecules that are widely expressed on the surface of differentiated cells and gene expression changes of transglutaminase2 (TGM2) are mechanisms involved in the development of DS. The purpose of this study was to assess the association of single nucleotide polymorphisms (SNP) of Intercellular Adhesion Molecule-1 (ICAM-1), chemokine (C-C motif) ligand 2 (CCL2) and TGM2 as inflammatory factors with differentiation syndrome susceptibility. METHODS: DNA was extracted from 133 APL patients and 100 normal controls. Assessment according to the PETHEMA criteria revealed that 13.5% of these patients experienced differentiation syndrome. Tetra-ARMS PCR and PCR-RFLP were done to amplify DNA fragments in APL patients with and without DS. Then DNA sequencing was done to validate the results. SNPStats, SPSS and Finch TV were used to analyze the results. RESULTS: A significant correlation was found between rs4811528 in the TGM2 gene and differentiation syndrome susceptibility (P = 0.002, 95% CI = 1.74-18.81, OR = 5.72) while rs5498 in ICAM-1, rs1024611 in CCL2, and rs7270785 in TGM2 genes showed no correlation with differentiation syndrome. The G allele of rs7270785 and rs4811528 showed a haplotypic association with differentiation syndrome (P = 0.03, 95% CI = 1.13-13.86, OR = 3.96). CONCLUSIONS: AA genotype of the TGM2 SNP (rs4811528) may be a risk factor for development of DS in patients with APL following the use of ATRA/ATO.

Longitudinal Analysis of Ventilation Perfusion Mismatch in Congenital Diaphragmatic Hernia Survivors.

OBJECTIVE: To determine the natural history of pulmonary function for survivors of congenital diaphragmatic hernia (CDH). STUDY DESIGN: This was a retrospective cohort study of survivors of CDH born during 1991-2016 and followed at our institution. A generalized linear model was fitted to assess the longitudinal trends of ventilation (V), perfusion (Q), and V/Q mismatch. The association between V/Q ratio and body mass index percentile as well as functional status was also assessed with a generalized linear model. RESULTS: During the study period, 212 patients had at least one V/Q study. The average ipsilateral V/Q of the cohort increased over time (P < .01), an effect driven by progressive reduction in relative perfusion (P = .012). A higher V/Q ratio was correlated with lower body mass index percentile (P < .001) and higher probability of poor functional status (New York Heart Association class III or IV) (P = .045). CONCLUSIONS: In this cohort of survivors of CDH with more severe disease characteristics, V/Q mismatch worsens over time, primarily because of progressive perfusion deficit of the ipsilateral side. V/Q scans may be useful in identifying patients with CDH who are at risk for poor growth and functional status.

Longitudinal Analysis of Pulmonary Function in Survivors of Congenital Diaphragmatic Hernia.

OBJECTIVE: To analyze longitudinal trends of pulmonary function testing in patients with congenital diaphragmatic hernia (CDH) followed in our multidisciplinary clinic. STUDY DESIGN: This was a retrospective cohort study of CDH patients born between 1991 and 2013. A linear mixed effects model was fitted to estimate the trends of percent predicted forced expiratory volume in 1 second (FEV1pp), percent predicted forced vital capacity (FVCpp), and FEV1/FVC over time. RESULTS: Of 268 patients with CDH who survived to discharge, 119 had at least 1 pulmonary function test study. The FEV1pp (P < .001), FVCpp (P = .017), and FEV1/FVC (P = .001) decreased with age. Compared with defect size A/B, those with defect size C/D had lower FEV1pp by an average of 11.5% (95% CI, 2.9%-20.1%; P = .010). A history of oxygen use at initial hospital discharge also correlated with decreased FEV1pp by an average of 8.0% (95% CI, 1.2%-15.0%; P = .023). CONCLUSIONS: In a select cohort of CDH survivors, average pulmonary function declines with age relative to expected population normative values. Those with severe CDH represent a population at risk for worsening pulmonary function test measurements who may benefit from recognition and monitoring for complications.

Identification and functional characterization of NbMLP28, a novel MLP-like protein 28 enhancing Potato virus Y resistance in Nicotiana benthamiana.

BACKGROUND: Major latex proteins (MLPs) belong to the MLP subfamily in Bet v 1 protein family and respond to both biotic and abiotic stresses, which play critical roles in plant disease resistance. As the type species of widely distributed and economically devastating Potyvirus, Potato virus Y (PVY) is one of the major constraints to important crop plants including tobacco (Nicotiana benthamiana) worldwide. Despite the great losses owing to PVY infection in tobacco, there is no previous study investigating the potential role of MLPs in developing resistance to viral infection. RESULTS: In this study, for the first time we have identified and functionally analyzed the MLP-like protein 28 from N. benthamiana, denoted as NbMLP28 and investigated its role in conferring resistance to N. benthamiana against PVY infection. NbMLP28 was localized to the plasmalemma and nucleus, with the highest level in the root. NbMLP28 gene was hypothesized to be triggered by PVY infection and was highly expressed in jasmonic acid (JA) signaling pathway. Further validation was achieved through silencing of NbMLP28 through virus-induced gene silencing (VIGS) that rendered N. benthamiana plants more vulnerable to PVY infection, contrary to overexpression that enhanced resistance. CONCLUSIONS: Taken together, this is the first study describing the role of NbMLP28 in tobacco against PVY infection and provide a pivotal point towards obtaining pathogen-resistant tobacco varieties through constructing new candidate genes of MLP subfamily.

Intralesional Steroid Injection Therapy for Esophageal Anastomotic Stricture Following Esophageal Atresia Repair.

OBJECTIVES: The role of intralesional steroid injection (ISI) in the treatment of anastomotic stricture in patients with esophageal atresia remains unclear. The aim of this study was to evaluate the efficacy and safety of ISI. METHODS: A total of 158 patients with esophageal atresia with at least 1 ISI for the treatment of esophageal anastomotic stricture between 2010 and 2017 were identified. The change in stricture diameter (ΔD) was compared between procedures with dilation alone (ISI-) and dilation with steroid injection (ISI+). RESULTS: A total of 1055 balloon dilations were performed (452 ISI+). The median ΔD was significantly greater in the ISI+ group: 1 mm (interquartile range [IQR] 0, 3) versus 0 mm (IQR -1, 1.5) (P < 0.0001). The ISI+ group had greater percentage of improved diameter (P < 0.0001) and lesser percentages of unchanged and decreased diameters at subsequent endoscopy (P = 0.0009, P = 0.003). Multivariable logistic regression confirmed the significance of ISI on increasing the likelihood of improved stricture diameter with an adjusted odds ratio of 3.24 (95% confidence interval: 2.15-4.88) (P < 0.001). The ΔD for the first 3 ISI+ procedures was greater than the ΔD for subsequent ISI+ procedures: 1 mm (IQR 0, 3) versus 0.5 mm (IQR-1.25, 2) (P = 0.001). There was no difference in perforation incidence between ISI+ and ISI- groups (P = 0.82). CONCLUSIONS: ISI with dilation was well tolerated and improved anastomotic stricture diameter more than dilation alone. The benefit of ISI over dilation alone was limited to the first 3 ISI procedures.

Tracheobronchomalacia, Tracheobronchial Compression, and Tracheobronchial Malformations: Diagnostic and Treatment Strategies.

Tracheobronchomalacia (TBM) is an excessive dynamic narrowing of the airway that is greatest with increased mediastinal pressure such as coughing, Valsalva, and forced expiration. Airway compression and/or cartilage malformation is a fixed or static narrowing of the airway typically caused by great vessel malposition and/or abnormalities and may also contribute to airway narrowing. Although imprecise and misleading, the term TBM is often used to represent both problems, static and dynamic airway narrowing, which only serves to confuse and may mislead the treatment team into ineffective therapies. The consequences of airway narrowing caused by dynamic TBM and/or static compression includes a range of clinical signs and symptoms, depending on the location, extent, and severity of the airway collapse. All patients with mild to severe TBM benefit from medical management to optimize airway clearance of mucus. The milder cases of TBM may become asymptomatic with this therapy, allowing time for the child to grow and the airway to enlarge without the consequences of recurrent infections. In cases of more severe TBM with clinical sequelae, more aggressive management may be warranted. Multiple options for surgical intervention are available. This article discusses the details of clinical presentation, evaluation, diagnosis, and a variety of treatments.

Full genome sequence analysis and putative host-shifting of Milk vetch dwarf virus infecting tobacco (Nicotiana tabacum) in China.

BACKGROUND: Tobacco production in China has been affected by plant viruses with Milk vetch dwarf virus (MDV) as a recent invader posing serious concern. According to most of the studies, MDV mainly infects hosts from Fabaceae family but in our previous study we reported its infection in tobacco plant (Nicotiana tabacum L.) in Shandong province. FINDINGS: In current study (2016-2017), tobacco plants (Nicotiana tabacum) with severe stunting, yellowing and axillary bunch of new leaves were observed in Zhengning, Gansu province. Isolate GSZN yielded into eight genomic circular single-stranded DNA components while no alphasatellite DNA was obtained. High percent identity of this isolate was recorded in overall nucleotide and amino acid assembly with reported MDV isolates worldwide. Phylogenetic analysis fetched into a separate sub-clade comprising of new isolate along with other tobacco infecting isolates of MDV. While recombination was predicted in DNA-C encoding Clink protein and DNA-U1, which may attribute towards the potential host-shifting phenomenon and ability of this virus to expand its host range. CONCLUSION: To our knowledge this is the first full genome annotation of a Nanovirus, infecting tobacco in natural field conditions, also this is the first extended analysis on host-shifting behavior of MDV.

Sensing Properties of Oxidized Nanostructured Silicon Surface on Vaporized Molecules.

Porous silicon has been intensely studied for the past several decades and its applications were found in photovoltaics, biomedicine, and sensors. An important aspect for sensing devices is their long⁻term stability. One of the more prominent changes that occur with porous silicon as it is exposed to atmosphere is oxidation. In this work we study the influence of oxidation on the sensing properties of porous silicon. Porous silicon layers were prepared by electrochemical etching and oxidized in a tube furnace. We observed that electrical resistance of oxidized samples rises in response to the increasing ambient concentration of organic vapours and ammonia gas. Furthermore, we note the sensitivity is dependent on the oxygen treatment of the porous layer. This indicates that porous silicon has a potential use in sensing of organic vapours and ammonia gas when covered with an oxide layer.

Vitamin D deficiency and possible link with Bony pain and onset of Osteoporosis.

OBJECTIVE: To explore if vitamin D deficiency had a direct correlation with bone pain or if it contributes in any way to the onset of osteoporosis. METHODS: The cross sectional Study was conducted from February to May 2014, presented at Liaquat National Hospital, Karachi, and comprised Orthopaedic outpatients. Who were questioned, examined and counselled, before a questionnaire was filled that included questions about their complaint, and its severity. Several blood test reports were incorporated including serum Vitamin D, to evaluate kidney and liver functions. Dual energy X-ray absorptiometry scans of the lumber and hip regions were also included. Data was collected manually and analysed using SPSS version 16. RESULTS: The mean age of the 65 subjects, was 52.±16 SD years, and 54(83.1%) were overweight with body mass index of 29.7kg/m2. Besides, 61(93.8%) had a positive association of low vitamin D levels as a causative agent for bone pain with mean pain severity index 6±1 SD. On the other hand 25(38.5%) were diagnosed as cases of osteoporosis, and, of them, 21(84%) had low vitamin D levels. CONCLUSIONS: Deficiency of vitamin D was directly related to the intensity of bone pain. Some patients had vitamin D deficiency along with osteoporosis, which may have aggravating effect in this context.

Validation of a PHIS Esophageal Atresia and Tracheoesophageal Fistula Cohort in ICD-10.

OBJECTIVE: Validation of a contemporary International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) congenital esophageal atresia/tracheoesophageal atresia (EA/TEF) cohort in the Pediatric Health Information System (PHIS) database. STUDY DESIGN: Database study, validation. SETTING: Tertiary care center. METHODS: Search methods used to validate an ICD-9-CM EA/TEF cohort in PHIS were modified for ICD-10-CM. A retrospectively and prospectively maintained clinical database at a single high-volume EA/TEF center was used for comparison. Patients treated between October 1, 2015 and July 31, 2022 were included. Searches progressively narrowed the cohort by ICD-10-CM diagnosis codes, expansion to include incorrectly coded as 'iatrogenic, age less than 30 days, and use of at least 1 ICD-10-CM procedure code. Results of PHIS data and institution data were compared for accuracy. RESULTS: The most refined search of PHIS and the EA/TEF clinical database yielded 93 and 84 patients, respectively. The sensitivity was 99% and positive predictive value was 94%. A PHIS search using these methods and encompassing 49 children's hospitals yielded an EA/TEF cohort of 2479 patients. CONCLUSION: We present a validated search method in the PHIS database to identify a high-fidelity cohort of EA/TEF patients for multi-institutional study. We have demonstrated that a carefully maintained clinical database may be used to validate cohorts in PHIS. This cohort allows for improved practice variability and outcomes study of EA/TEF patients. Similar methods may be employed to generate other rare disease cohorts in PHIS. LEVEL OF EVIDENCE: Level 4.

Primary Posterior Tracheopexy at Time of Esophageal Atresia Repair Significantly Reduces Respiratory Morbidity.

PURPOSE: Esophageal atresia with tracheoesophageal fistula (EA/TEF) is often associated with tracheobronchomalacia (TBM), which contributes to respiratory morbidity. Posterior tracheopexy (PT) is an established technique to treat TBM that develops after EA/TEF repair. This study evaluates the impact of primary PT at the time of initial EA/TEF repair. METHODS: Review of all newborn primary EA/TEF repairs (2016-2021) at two institutions. Long-gap EA and reoperative cases were excluded. Based on surgeon preference and preoperative bronchoscopy, neonates underwent primary PT (EA + PT Group) or not (EA Group). Perioperative, respiratory and nutritional outcomes within the first year of life were evaluated. RESULTS: Among 63 neonates, 21 (33%) underwent PT during EA/TEF repair. Groups were similar in terms of demographics, approach, and complications. Neonates in the EA + PT Group were significantly less likely to have respiratory infections requiring hospitalization within the first year of life (0% vs 26%, p = 0.01) or blue spells (0% vs 19%, p = 0.04). Also, they demonstrated improved weight-for-age z scores at 12 months of age (0.24 vs -1.02, p < 0.001). Of the infants who did not undergo primary PT, 10 (24%) developed severe TBM symptoms and underwent tracheopexy during the first year of life, whereas no infant in the EA + PT Group needed additional airway surgery (p = 0.01). CONCLUSION: Incorporation of posterior tracheopexy during newborn EA/TEF repair is associated with significantly reduced respiratory morbidity within the first year of life. LEVEL OF EVIDENCE: Level III.

Diagnostic Accuracy of Laryngeal Ultrasound for Evaluating Vocal Fold Movement Impairment in Children.

PURPOSE: Vocal fold movement impairment (VFMI) secondary to recurrent laryngeal nerve (RLN) injury is a common source of morbidity after pediatric cervical, thoracic, and cardiac procedures. Flexible laryngoscopy (FL) is the gold standard to diagnose VFMI yet can be challenging to perform and/or risks possible clinical decompensation in some children and is an aerosolizing procedure. Laryngeal ultrasound (LUS) is a potential non-invasive alternative, but limited data exists in the pediatric surgical population regarding its efficacy. We aimed to investigate the diagnostic accuracy of LUS compared to FL in evaluating VFMI. METHODS: A prospective, single-center, single-blinded (rater) cohort study was undertaken on perioperative pediatric patients at risk for RLN injury. Patients underwent FL and LUS. Cohen's kappa was used to determine chance-corrected agreement. RESULTS: Between 2021 and 2023, 85 paired evaluations were performed with patients having a median (IQR) age of 10 (4, 42) months and weight of 7.5 (5.4, 13.4) kilograms. The prevalence of VFMI was 27.1%. Absolute agreement between evaluations was 98.8% (kappa 0.97, 95% CI: 0.91-1.00, P < 0.001). The sensitivity and specificity of LUS in detecting VFMI was 95.7% and 100%, yielding a positive predictive value (PPV) of 100% and negative predictive value (NPV) of 98.4% (95% CI: 90-100%). Diagnostic accuracy was 98.8% (95% CI: 93-100%). CONCLUSION: LUS is a highly accurate modality in evaluating VFMI in children. While FL remains the gold standard for diagnosis, LUS offers a low-risk screening modality for children at risk for VFMI such that only those with an abnormal LUS or presence of clinical symptoms discordant with LUS findings should undergo FL. TYPE OF STUDY: Prospective, single-center, single blinded (rater), cohort study. LEVEL OF EVIDENCE: Level II.

Bronchoscopic Localization of Tracheoesophageal Fistula in Newborns with Esophageal Atresia: Intubate Above or Below the Fistula?

PURPOSE: In neonates with suspected type C esophageal atresia and tracheoesophageal fistula (EA/TEF) who require preoperative intubation, some texts advocate for attempted "deep" or distal-to-fistula intubation. However, this can lead to gastric distension and ventilatory compromise if a distal fistula is accidently intubated. This study examines the distribution of tracheoesophageal fistula locations in neonates with type C EA/TEF as determined by intraoperative bronchoscopy. METHODS: This was a single-center retrospective review of neonates with suspected type C EA/TEF who underwent primary repair with intraoperative bronchoscopy between 2010 and 2020. Data were collected on demographics and fistula location during bronchoscopic evaluation. Fistula location was categorized as amenable to blind deep intubation (>1.5 cm above carina) or not amenable to blind deep intubation intubation (≤1.5 cm above carina or carinal). RESULTS: Sixty-nine neonates underwent primary repair of Type C EA/TEF with intraoperative bronchoscopy during the study period. Three patients did not have documented fistula locations and were excluded (n = 66). In total, 49 (74 %) of patients were found to have fistulas located ≤1.5 cm from the carina that were not amenable to blind deep intubation. Only 17 patients (26 %) had fistulas >1.5 cm above carina potentially amenable to blind deep intubation. CONCLUSIONS: Most neonates with suspected type C esophageal atresia and tracheoesophageal fistula have distal tracheal and carinal fistulas that are not amenable to blind deep intubation. LEVEL OF EVIDENCE: Level III.

Surveillance Endoscopy in Pediatric Esophageal Atresia: Toward an Evidence-Based Algorithm.

BACKGROUND: Individuals with esophageal atresia (EA) have lifelong increased risk for mucosal and structural pathology of the esophagus. The use of surveillance endoscopy to detect clinically meaningful pathology has been underexplored in pediatric EA. We hypothesized that surveillance endoscopy in pediatric EA has high clinical yield, even in the absence of symptoms. STUDY DESIGN: The medical records of all patients with EA who underwent at least 1 surveillance endoscopy between March 2004 and March 2023 at an international EA referral center were retrospectively reviewed. The primary outcomes were endoscopic identification of pathology leading to an escalation in medical, endoscopic, or surgical management. Logistic regression analysis examined predictors of actionable findings. Nelson-Aalen analysis estimated optimal endoscopic surveillance intervals. RESULTS: Five hundred forty-six children with EA underwent 1,473 surveillance endoscopies spanning 3,687 person-years of follow-up time. A total of 770 endoscopies (52.2%) in 394 unique patients (72.2%) had actionable pathology. Esophagitis leading to escalation of therapy was the most frequently encountered finding (484 endoscopies, 32.9%), with most esophagitis attributed to acid reflux. Barrett's esophagus (intestinal metaplasia) was identified in 7 unique patients (1.3%) at a median age of 11.3 years. No dysplastic lesions were identified. Actionable findings leading to surgical intervention were found in 55 children (30 refractory reflux and 25 tracheoesophageal fistulas). Significant predictors of actionable pathology included increasing age, long gap atresia, and hiatal hernia. Symptoms were not predictive of actionable findings, except dysphagia, which was associated with stricture. Nelson-Aalen analysis predicted occurrence of an actionable finding every 5 years. CONCLUSIONS: Surveillance endoscopy uncovers high rates of actionable pathology even in asymptomatic children with EA. Based on the findings of the current study, a pediatric EA surveillance endoscopy algorithm is proposed.

Surface-Enhanced Raman Scattering (SERS) in Combination with PCA and PLS-DA for the Evaluation of Antibacterial Activity of 1-Isopentyl-3-pentyl-1H-imidazole-3-ium Bromide against Bacillus subtilis.

In the current study, surface-enhanced Raman scattering (SERS) was performed to evaluate the antibacterial activity of lab-synthesized drug (1-isopentyl-3-pentyl-1H-imidazole-3-ium bromide salt) and commercial drug tinidazole againstBacillus subtilis. The changes in SERS spectral features were studied for unexposed bacillus and exposed one with various dosages of drug synthesized in the lab (1-isopentyl-3-pentyl-1H-imidazole-3-ium bromide salt), and SERS bands were assigned associated with the drug-induced biochemical alterations in bacteria. Multivariate data analysis tools including principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) have been utilized to analyze the antibacterial activity of the imidazole derivative (lab drug). PCA was employed in differentiating all the SERS spectral data sets associated with the various doses of the lab-synthesized drug. There is clear discrimination among the spectral data sets of a bacterial strain treated with different concentrations of the drug, which are analyzed by PLS-DA with 86% area under the curve in receiver operating curve (ROC), 99% sensitivity, 100% accuracy, and 98% specificity. Various dominant spectral features are observed with a gradual increase in the different concentrations of the applied drug including 715, 850, 1002, 1132, 1237, 1396, 1416, and 1453 cm-1, which indicate the possible biochemical changes caused in bacteria during the antibacterial activity of the lab-synthesized drug. Overall, the findings show that imidazole and imidazolium compounds generated from tinidazole with various alkyl lengths in the amide substitution can be effective antibacterial agents with low cytotoxicity in humans, and these results indicate the efficiency of SERS in pharmaceuticals and biomedical applications.

Rapid Identification and Quantification of Adulteration in Methyl Eugenol using Raman Spectroscopy Coupled with Multivariate Data Analysis.

Identification of adulterants in commercial samples of methyl eugenol is necessary because it is a botanical insecticide, a tephritid male attractant lure that is used to attract and kill invasive pests such as oriental fruit flies and melon flies on crops. In this study, Raman spectroscopy was used to qualitatively and quantitatively assess commercial methyl eugenol along with adulterants. For this purpose, commercial methyl eugenol was adulterated with different concentrations of xylene. The Raman spectral features of methyl eugenol and xylene in liquid formulations were examined, and Raman peaks were identified as associated with the methyl eugenol and adulterant. Principal component analysis (PCA) and partial least-squares regression analysis (PLSR) have been used to qualitatively and quantitatively analyze the Raman spectral features. PCA was applied to differentiate Raman spectral data for various concentrations of methyl eugenol and xylene. Additionally, PLSR has been used to develop a predictive model to observe a quantitative relationship between various concentrations of adulterated methyl eugenol and their Raman spectral data sets. The root-mean-square errors of calibration and prediction were calculated using this model, and the results were found to be 1.90 and 3.86, respectively. The goodness of fit of the PLSR model is found to be 0.99. The proposed approach showed excellent potential for the rapid, quantitative detection of adulterants in methyl eugenol, and it may be applied to the analysis of a range of pesticide products.

Surface-enhanced Raman spectroscopy for characterization of filtrates of blood serum samples from patients with tuberculosis obtained by 50 kDa filtration devices.

The ability of surface-enhanced Raman spectroscopy (SERS) to generate spectroscopic fingerprints has made it an emerging tool for biomedical applications. The objective of this study is to confirm the potential use of Raman spectroscopy for early disease diagnosis based on blood serum. In this study, a total of sixty blood serum samples, consisting of forty from diseased patients and twenty (controls) from healthy individuals, was used. Because disease biomarkers, found in the lower molecular weight fraction, are suppressed by higher molecular weight proteins, 50 kDa Amicon ultrafiltration centrifugation devices were used to produce two fractions from whole blood serum consisting of a filtrate, which is a low molecular weight fraction, and a residue, which is a high molecular weight fraction. These fractions were then analyzed, and their SERS spectral data were compared with those of healthy fractions. The SERS technique was utilized on blood serum, filtrate and residue of patients with tuberculosis to identify characteristic SERS spectral features associated with the development of disease, which can be used to differentiate them from healthy samples using silver nanoparticles as a SERS substrate. For further analysis, the effective chemometric technique of principal component analysis (PCA) was used to qualitatively differentiate all the analyzed samples based on their SERS spectral features. Partial least squares discriminant analysis (PLS-DA) accurately classified the filtrate portions of healthy and tuberculosis samples with 97% accuracy, 97% specificity, 98% sensitivity, and an area under the receiver operating characteristic (AUROC) curve of 0.74.

Surface-enhanced Raman spectroscopy for the characterization of bacterial pellets of Staphylococcus aureus infected by bacteriophage.

Drug-resistant pathogenic bacteria are a major cause of infectious diseases in the world and they have become a major threat through the reduced efficacy of developed antibiotics. This issue can be addressed by using bacteriophages, which can kill lethal bacteria and prevent them from causing infections. Surface-enhanced Raman spectroscopy (SERS) is a promising technique for studying the degradation of infectious bacteria by the interaction of bacteriophages to break the vicious cycle of drug-resistant bacteria and help to develop chemotherapy-independent remedial strategies. The phage (viruses)-sensitive Staphylococcus aureus (S. aureus) bacteria are exposed to bacteriophages (Siphoviridae family) in the time frame from 0 min (control) to 50 minutes with intervals of 5 minutes and characterized by SERS using silver nanoparticles as SERS substrate. This allows us to explore the effects of the bacteriophages against lethal bacteria (S. aureus) at different time intervals. The differentiating SERS bands are observed at 575 (C-C skeletal mode), 620 (phenylalanine), 649 (tyrosine, guanine (ring breathing)), 657 (guanine (COO deformation)), 728-735 (adenine, glycosidic ring mode), 796 (tyrosine (C-N stretching)), 957 (C-N stretching (amide lipopolysaccharides)), 1096 (PO2 (nucleic acid)), 1113 (phenylalanine), 1249 (CH2 of amide III, N-H bending and C-O stretching (amide III)), 1273 (CH2, N-H, C-N, amide III), 1331 (C-N stretching mode of adenine), 1373 (in nucleic acids (ring breathing modes of the DNA/RNA bases)) and 1454 cm-1 (CH2 deformation of saturated lipids), indicating the degradation of bacteria and replication of bacteriophages. Multivariate data analysis was performed by employing principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) to study the biochemical differences in the S. aureus bacteria infected by the bacteriophage. The SERS spectral data sets were successfully differentiated by PLS-DA with 94.47% sensitivity, 98.61% specificity, 94.44% precision, 98.88% accuracy and 81.06% area under the curve (AUC), which shows that at 50 min interval S. aureus bacteria is degraded by the replicating bacteriophages.