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AbstractA sensitive electrochemical nanosensor based on a glassy carbon electrode modified by carbon nanofibers (CNFs) was developed to simultaneously determine kanamycin and ampicillin. Under optimized conditions, the nanosensor showed a wide dynamic linear range (1.0 × 10−11-1.0 × 10−6 M and 1.0 × 10−10-1.0 × 10−6 M) and a low detection limit (6.12 × 10−12 M and 1.47 × 10−11 M) for kanamycin and ampicillin, respectively. The multivariable calibration of OSC-PLS was adopted to separate the obtained voltammograms. The root mean square error of prediction (RMSEPs) of kanamycin and ampicillin using the OSC-PLS model were 0.05 and 0.08, respectively. The method was used to simultaneously determine kanamycin and ampicillin in tap water. [ABSTRACT FROM AUTHOR]

Klebsiella species are becoming a major global public health concern. In particular, the increase in multidrug‐resistant strains is a cause for concern. This study was aimed at determining the antibiotic susceptibility of two different isolates of Klebsiella quasipneumoniae subsp. similipneumoniae and determining the virulence characteristics and bacterial morphology under subminimum inhibitory concentrations (sub‐MICs) of antibiotics. In this study, two multidrug‐resistant K. quasipneumoniae subsp. similipneumoniae isolates were identified, one of which was clinical, and the other was isolated from freshwater. The MICs of the antibiotics meropenem, chloramphenicol, ciprofloxacin, and kanamycin were determined for these isolates. The effects of the sub‐MICs on the virulence and morphological characteristics of the bacteria were investigated in comparison with K. pneumoniae (ATCC 13883). The MICs of meropenem, chloramphenicol, ciprofloxacin, and kanamycin were 0.04, 20, 2, and 8 μg/mL in the clinical isolate; 0.2, 15, 5, and 2 μg/mL in the freshwater isolate; and 0.03, 3, 0.1, and 0.3 μg/mL for K. pneumoniae. The biofilm‐forming ability of K. quasipneumoniae subsp. similipneumoniae isolates decreased with antibiotic sub‐MICs. Siderophore activity increased only with MIC/4 of kanamycin and MIC/2 of chloramphenicol in the clinical isolate (p > 0.05). Furthermore, bacterial morphology and expression of virulence genes were affected differently by the sub‐MICs. This study showed that biofilm formation decreased and that the changes in bacterial morphology and expression of virulence genes were very different in the presence of 1/2 and 1/4 sub‐MIC antibiotics. [ABSTRACT FROM AUTHOR]

Multi‐target detection is a notable development direction in the field of analytical methods, boasting significant potential for breakthroughs in complex sample detection. Herein, an extended gate field‐effect transistor (EGFET) sensor array for ultrasensitive and multi‐target detection of antibiotics is developed. To enhance the recognition ability for diverse antibiotics, a dual‐recognition strategy based on tailor‐made molecularly imprinted polymer (MIP) and aptamer is adopted to fabricate the extended gate electrode (sensing electrode). The dual‐recognition strategy‐based EGFET exhibits superior sensitivity, selectivity, and stability compared to single recognition probes due to the synergistic effect of the affinities of MIP and specific aptamer. The developed sensor array can detect three types of antibiotics, including ampicillin, amoxicillin, and kanamycin, at the same time with record‐low detection limit (fM level) and a detection range spanning six orders of magnitude. The practical detection of antibiotics in various samples (tap water, river water, milk, honey, and artificial urine) further validates the feasibility of the sensor array in practical applications. The key advantages of flexibility, high sensitivity and selectivity, and multifunctionality demonstrate the high potential of EGFET sensor array for simultaneous detection of multiple target molecules. [ABSTRACT FROM AUTHOR]

A fluorescent and photoelectrochemical (PEC) dual-mode biosensor based on target biorecognition-triggered cyclic amplification was constructed for Kana detection. With the assistance of the catalyzed reaction of exonuclease III, a Kana-aptamer DNA duplex was designed for conducting the cyclic release of G-rich DNA sequence as well as output DNA S2. The released G-rich sequence triggers the fluorescence (FL) of thioflavin T (ThT), the intensity of which is positively correlated with the Kana concentration. The linear range is 0.2 to 30 nM, and the detection limit reaches 0.07 nM. Simultaneously, the released output DNA S2 was captured by Fe3O4@CdTe-probe ssDNA and then combined with methylene blue to realize the transduction of polarity-reversed PEC signal, leading to the sensitive detection of Kana with a linear range of 0.2 to 40 nM and a calculated detection limit of 0.2 nM. The outstanding performance endows the dual-mode biosensor a promising prospect for practical application. [ABSTRACT FROM AUTHOR]

Aptamer-based lateral flow analysis (Apt-LFAs) has promising applications in many fields. Nanozymes have demonstrated high potential in improving the performance of Apt-LFAs and have been increasingly utilized in recent studies. In this study, we developed a nanozyme-based Apt-LFA for the rapid and sensitive detection of kanamycin by using a novel dual-functionalized AuNPs@polyA-DNA/GpG-Cu2+ nanozyme as a nanoprobe. In the nanoprobe design, the polyA-cDNA strand can discriminate a kanamycin aptamer from the kanamycin/aptamer complex, and the GpG-Cu2+ complex can amplify the detection signal by catalyzing the chromogenic reaction. The nanozyme Apt-LFA can quantify kanamycin in the range of 1–250 ng/mL with an LOD of 0.08 ng/mL, which demonstrated a 4-fold sensitivity improvement and had a wider linear range than the conventional AuNP-based LFA. The Apt-LFA was successfully applied to the detection of kanamycin in honey with good recoveries. Our dual-functionalized AuNP nanoprobe is easily prepared and can be highly compatible with the conventional AuNP-DNA-based LFA platform; thus, it can be extended to the application of Apt-LFAs for other small molecules. [ABSTRACT FROM AUTHOR]

Eclipta alba (Linn.) Hassk. (Asteraceae) is a high value medicinal plant which possesses diverse medicinal properties. It is an important herb for the treatment of various disorders, and is primarily used as a hepatoprotectant. Its major biochemical constituents include wedelolactone and dimethyl-wedelolactone (coumestans), which possess anti-hepatotoxic properties. Due to its numerous medicinal properties, it is in high demand by the pharmaceutical industry and therefore requires urgent biotechnological interventions for its improvement. Therefore, the present study was constructed with the aim of developing an efficient genetic transformation protocol for E. alba, which will help in the mass production of the active compounds found in E. alba. Agrobacterium tumefaciens strain LBA 4404, containing vector pBI121, was used to genetically transform the plant, and the effect of various factors such as infection type, light cycle effect, effect of pH, among others, on the genetic transformation efficiency was analyzed. Regenerated transformed shoots were confirmed using the standard Polymerase Chain Reaction PCR method. Kanamycin-resistant and beta- glucurosidaseGUS-positive shoots indicated the development of transgenic shoots in E. alba. Amplification of nptll and uidA genes confirmed the integration of t-DNA transgenic shoots. In conclusion, various factors affecting the transformation efficiency were analyzed, and a reliable A. tumefaciens-mediated genetic transformation protocol was developed. [ABSTRACT FROM AUTHOR]

A novel "turn-on" aptasensor for kanamycin (Kana) detection based on a new Förster resonance energy transfer (FRET) pair is reported. A new organic small molecule was employed as a high-efficiency quencher for fluorophore. Based on specific interactions between ssDNA and the quencher, an ingenious and amplified strategy was designed. In the absence of the target, the fluorescence of the fluorophore labeled at the end of the aptamer was quenched. After the binding of the aptamer to the target, the fluorescence was recovered and amplified. The proposed aptasensor showed high specificity, selectivity, and stability in complicated systems. With the P3-based strategy, the limit of detection for Kana is estimated to be 10 nM, which is much lower than the maximum allowable concentration in milk. The recoveries of spiked Kana in milk were in the range 99.8 ~ 105.3% (n = 3). Fortunately, this novel method can be easily extended to other antibiotics such as tobramycin by simply replacing the aptamer, showing great potential as a universal platform for selective, sensitive, and rapid detection of hazardous analytes in food samples. [ABSTRACT FROM AUTHOR]

An electrochemical aptasensor was developed by utilizing a DNA walker driven by catalytic hairpin assembly (CHA) with kanamycin as the model analyte. Kanamycin bound to the aptamer, causes the release of DNA walker, triggers the CHA reaction, leads to the cyclic movement of the walker's long arm, and results in cascade amplification of the signal. The guanine-rich sequences of the double-stranded products produced by CHA were folded to form G-quadruplex structures, with electrochemical active molecules Hemin embedded, forms G-quadruplex/Hemin complexes in situ on the electrode surface, thereby achieving sensitive, efficient, and label-free detection of kanamycin with a limit of detection (LOD) of 0.27 pM (S/N = 3). Meaningfully, the aptasensor demonstrated high sensitivity and reliability in the detection of kanamycin in milk and livestock wastewater samples, suggesting that it has great potential for application in detecting antibiotics in food products and water samples from the environment. [ABSTRACT FROM AUTHOR]

As a kind of aminoglycoside antibiotics, kanamycin (KAN) is widely applied to animal husbandry and aquaculture. However, the abuse of KAN causes the large-scale discharge of it into rivers, lakes and groundwater, which threatens environmental safety and human health. Therefore, it is imperative to develop a method that is applicable to detect KAN in an efficient and accurate way. The colorimetric method based on enzymes provides a feasible solution for the detection of organic pollutants. However, the extensive application of natural enzymes is constrained by high cost and low stability. Herein, a polyoxometalate-based nanozyme, namely [H7SiW9V3O40(DPA)3]·4H2O (SiW9V3/DPA) (DPA = dipyridylamine), is synthesized. As a low-cost nanozyme with high stability compared to natural enzymes, SiW9V3/DPA performs well in laccase-mimicking activity. It can be used to induce chromogenic reaction between 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP), which generates red products. With the addition of KAN, the color fades. That is to say, KAN can be detected with colorimetric assay in the concentration range 0.1 to 100 μM with high selectivity and low limit of detection (LOD) of 6.28 μM. Moreover, SiW9V3/DPA is applied to KAN detection in lake and river water and milk with satisfactory results. To sum up, polyoxometalate-based nanozyme is expected to provide a promising solution to the detection of organic pollutants in the aquatic environment. [ABSTRACT FROM AUTHOR]

Abstract Fluoroquinolone resistance is a major challenge in treating Multidrug-Resistant Tuberculosis globally. The GenoType MTBDRsl Ver 2.0, endorsed by the WHO, was used to characterize fluoroquinolone resistance. The fluoroquinolone resistance rates in the MDR-TB, Rifampicin-Resistant TB, and non-MDR-TB were 33%, 16.5%, and 5.4%, respectively. The most common mutation found in fluoroquinolone-resistant isolates was D94G (49.5%) in the gyrA gene. Of the 150 MDR-TB isolates, the prevalence of Extensively Drug-Resistant Tuberculosis and pre-XDR-TB was 1.33% and 30%, respectively. Among the 139 RR-TB isolates, pre-XDR-TB prevalence was 15.8%. The fluoroquinolone resistance rates were 5.12% among the 1230 isoniazid-monoresistant isolates. The study found that MDR-TB and RR-TB have higher risk of fluoroquinolone resistance than non-MDR tuberculosis. Rifampicin-resistant isolates with a mutation at codon S450L have a higher risk (RR = 12.96; 95%CI: 8.34–20.13) of developing fluoroquinolone resistance than isolates with mutations at other codons in the rpoB gene. Isoniazid-resistant isolates with a mutation at codon S315T have a higher risk (RR = 2.09; 95%CI: 1.25–3.50) of developing fluoroquinolone resistance. The study concludes that rapid diagnosis of fluoroquinolone resistance before starting treatment is urgently needed to prevent the spread and increase of resistance and to achieve better treatment outcomes in areas where it is higher.

Eclipta alba (Linn.) Hassk. (Asteraceae) is a high value medicinal plant which possesses diverse medicinal properties. It is an important herb for the treatment of various disorders, and is primarily used as a hepatoprotectant. Its major biochemical constituents include wedelolactone and dimethyl-wedelolactone (coumestans), which possess anti-hepatotoxic properties. Due to its numerous medicinal properties, it is in high demand by the pharmaceutical industry and therefore requires urgent biotechnological interventions for its improvement. Therefore, the present study was constructed with the aim of developing an efficient genetic transformation protocol for E. alba, which will help in the mass production of the active compounds found in E. alba. Agrobacterium tumefaciens strain LBA 4404, containing vector pBI121, was used to genetically transform the plant, and the effect of various factors such as infection type, light cycle effect, effect of pH, among others, on the genetic transformation efficiency was analyzed. Regenerated transformed shoots were confirmed using the standard Polymerase Chain Reaction PCR method. Kanamycin-resistant and beta- glucurosidaseGUS-positive shoots indicated the development of transgenic shoots in E. alba. Amplification of nptll and uidA genes confirmed the integration of t-DNA transgenic shoots. In conclusion, various factors affecting the transformation efficiency were analyzed, and a reliable A. tumefaciens-mediated genetic transformation protocol was developed.

Fluoroquinolone resistance is a major challenge in treating Multidrug-Resistant Tuberculosis globally. The GenoType MTBDRsl Ver 2.0, endorsed by the WHO, was used to characterize fluoroquinolone resistance. The fluoroquinolone resistance rates in the MDR-TB, Rifampicin-Resistant TB, and non-MDR-TB were 33%, 16.5%, and 5.4%, respectively. The most common mutation found in fluoroquinolone-resistant isolates was D94G (49.5%) in the gyrA gene. Of the 150 MDR-TB isolates, the prevalence of Extensively Drug-Resistant Tuberculosis and pre-XDR-TB was 1.33% and 30%, respectively. Among the 139 RR-TB isolates, pre-XDR-TB prevalence was 15.8%. The fluoroquinolone resistance rates were 5.12% among the 1230 isoniazid-monoresistant isolates. The study found that MDR-TB and RR-TB have higher risk of fluoroquinolone resistance than non-MDR tuberculosis. Rifampicin-resistant isolates with a mutation at codon S450L have a higher risk (RR = 12.96; 95%CI: 8.34–20.13) of developing fluoroquinolone resistance than isolates with mutations at other codons in the rpoB gene. Isoniazid-resistant isolates with a mutation at codon S315T have a higher risk (RR = 2.09; 95%CI: 1.25–3.50) of developing fluoroquinolone resistance. The study concludes that rapid diagnosis of fluoroquinolone resistance before starting treatment is urgently needed to prevent the spread and increase of resistance and to achieve better treatment outcomes in areas where it is higher. [ABSTRACT FROM AUTHOR]

Background: Methyltransferase-like 3 (METTL3), a component of the N6-methyladenosine (m6A) methyltransferase family, exhibits significant expression in HEI-OC1 cells and cochlear explants. Aminoglycoside antibiotics, known for their ototoxic potential, frequently induce irreversible auditory damage in hair cells, predominantly through oxidative stress mechanisms. However, the specific role of METTL3 in kanamycin-induced hair cell loss remains unclear. Objective: This study aims to elucidate the mechanisms by which METTL3 contributes to kanamycin-induced ototoxicity. Methods and Results: In vivo experiments demonstrated a notable reduction in METTL3 expression within cochlear explants following kanamycin administration, concomitant with the formation of stress granules (SGs). Similarly, a 24-hour kanamycin treatment led to decreased METTL3 expression and induced SG formation both in HEI-OC1 cells and neonatal cochlear explants, corroborating the in vivo observations. Lentivirus-mediated transfection was employed to overexpress and knockdown METTL3 in HEI-OC1 cells. Knockdown of METTL3 resulted in increased reactive oxygen species (ROS) levels and apoptosis induced by kanamycin, while concurrently reducing SG formation. Conversely, overexpression of METTL3 attenuated ROS generation, decreased apoptosis rates, and promoted SG formation induced by kanamycin. Therefore, METTL3-mediated SG formation presents a promising target for mitigating kanamycin-induced ROS generation and the rate of apoptosis. Conclusion: This finding indicates that METTL3-mediated SG formation holds potential in mitigating kanamycin-induced impairments in cochlear hair cells by reducing ROS formation and apoptosis rates. [ABSTRACT FROM AUTHOR]

Haematococcus lacustris (Girod-Chantrans) Rostafinski (Chlorophyta) is the richest microalgal source of astaxanthin. Natural astaxanthin from H. lacustris has been widely studied and used for commercial production worldwide. In this study, we examined the effects of 11 antibiotics (dihydrostreptomycin sulphate, neomycin, chloramphenicol, penicillin, streptomycin, ampicillin, kanamycin, gentamycin, hygromycin B, tetracycline, and paromomycin) on the biomass dry weight, growth, and astaxanthin yield of H. lacustris using Jaworski's medium without a nitrogen source. Astaxanthin content in H. lacustris was improved in the presence of ampicillin (0.25 g/L, 0.5 g/L, 1 g/L), chloramphenicol (0.25 g/L), and penicillin (0.25 g/L, 0.5 g/L, 1 g/L) in comparison to the control on day 15. The greatest increase in astaxanthin content on day 15 (6.69-fold) was obtained with the addition of penicillin (0.5 g/L) in comparison to the control. Similarly, on day 15, the cell numbers were also the highest for the H. lacustris culture grown with the addition of penicillin (0.5 g/L). [ABSTRACT FROM AUTHOR]

Rare earth (RE)-doped CaS phosphors have been widely used as light-emitting components in various fields. Nevertheless, the application of nanosized CaS particles is still significantly limited by their poor water resistance and weak luminescence. Herein, a lattice-matching strategy is developed by growing an inert shell of cubic NaYF4 phase on the CaS luminescent core. Due to their similarity in crystal structure, a uniform core–shell heterostructure (CaS:Ce3+@NaYF4) can be obtained, which effectively protects the CaS:Ce3+ core from degradation in aqueous environment and enhances its luminescence intensity. As a proof of concept, a label-free aptasensor is further constructed by combining core–shell CaS:Ce3+@NaYF4 and Au nanoparticles (AuNPs) for the ultrasensitive detection of kanamycin antibiotics. Based on the efficient FRET process, the detection linear range of kanamycin spans from 100 to 1000 nM with a detection limit of 7.8 nM. Besides, the aptasensor shows excellent selectivity towards kanamycin antibiotics, and has been successfully applied to the detection of kanamycin spiked in tap water and milk samples, demonstrating its high potential for sensing applications. [ABSTRACT FROM AUTHOR]

Background and Aim: There is an increasing rate of antibiotic resistance in Neisseria gonorrhoeae (N. gonorrhoeae). Several obstacles affect the culture and susceptibility testing of N. gonorrhoeae. This study was aimed to determine the antimicrobial susceptibility pattern and molecular characteristics in multidrug-resistant (MDR) N. gonorrhoeae in Jakarta, Indonesia. Materials and Methods: Forty-one endocervical specimens were streaked onto the chocolate agar and then gently rolled onto a glass object. The suspected colonies were identified by Gram staining, oxidase testing, and biochemical identification using VITEK® 2 NH cards. The antimicrobial susceptibility testing was performed using the disk diffusion or E-test method. Molecular detection of N. gonorrhoeae was carried out using the SYBR green real-time PCR targeting the opa gene. The multiplex real-time PCR with high-resolution melting (HRM) was also conducted to analyze the gene mutations in penA and 23S rRNA. DNA sequencing was used to confirm penA and 23S rRNA mutations. Results: SYBR green real-time PCR against the opa gene on direct specimens detected N. gonorrhoeae with higher positivity rate (49%) compared to the culture (34%). Susceptibility testing detected 11.1% N. gonorrhoeae resistant to cefixime, whereas resistance to azithromycin and ceftriaxone was 0%. The resistance of N. gonorrhoeae to levofloxacin and kanamycin was 33.3% and 88.9%, respectively. All isolates were resistant to penicillin, tetracycline and ciprofloxacin. There were no mutations in the penA genes Ala501, Gly545Ser, 23S rRNA A2059G and C2611T. Conclusion: Cefixime resistance was found in our samples. This resistence was not correlated with penA gene mutations. All isolates were still susceptiblle to azithromycin, which was in line with its molecular characteristics. The SYBR green real-time PCR targeting the opa gene successfully detected the DNA extracted from endocervical swabs as N. gonorrhoeae. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is a powerhouse of the textile industry, playing a crucial role in global fibre production. Unfortunately, cotton is not the easiest crop to genetically modify, it is highly recalcitrant with respect to transformation and regeneration. Despite progress in transformation protocols, it's efficiency in many elite cotton varieties still remains around 0.01-3%. Certain cotton genotypes, such as coker, show more favourable responses to gene transfer, resulting in a dependence on these varieties for genetic alterations. A reliable and efficient protocol for transforming cotton was standardized in Gossypium hirsutum cv HS6. Shoot tip explants from in-vitro germinated cotton seedlings were cultured on MS medium. These explants were genetically transformed with Agrobacterium tumefaciens strain LBA4404, carrying pBI121 expression vector containing neomycin phosphotransferase (nptII) marker gene. The explants were consistently transferred every week to fresh MS selection media. Remarkably, unlike previous protocols that utilized various phytohormones for cotton regeneration, our procedure does not involve use of any phytohormones, yet the growth of shoots and roots was not affected by the absence of phytohormones. Interestingly, natural hormones within cotton plants regulate growth, eliminating the need for external phytohormones in the medium during tissue culture. The overall transformation efficiency reported in the current protocol was 5%, which is significantly higher than previous reports. [ABSTRACT FROM AUTHOR]

Aminoglycosides are crucial antibiotics facing challenges from bacterial resistance. This study addresses the importance of aminoglycoside modifying enzymes in the context of escalating resistance. Drawing upon over two decades of structural data in the Protein Data Bank, we focused on two key antibiotics, neomycin B and kanamycin A, to explore how the aminoglycoside structure is exploited by this family of enzymes. A systematic comparison across diverse enzymes and the RNA A‐site target identified common characteristics in the recognition mode, while assessing the adaptability of neomycin B and kanamycin A in various environments. [ABSTRACT FROM AUTHOR]

Background: The medical significance of drug resistance in Mycobacterium tuberculosis, particularly the multi-drug-resistant strains, has a significant impact on the challenge of treating the disease and controlling its prevalence. Objectives: The objective of this study was to determine the frequency of rrs and rpsL mutations in aminoglycoside-resistant Mycobacterium tuberculosis strains isolated from clinical specimens in western Iran. Methods: This descriptive cross-sectional study was conducted on positive sputum specimens obtained from 40 pulmonary disease patients referred to the Kermanshah Lung Disease Center. The sputum specimens were cultured on the Löwenstein-Jensen medium. Specimens were assessed for the presence of genes resistant and susceptible to aminoglycosides using gene expression methods. DNA extraction was performed using the G-spin kit, and the Polymerase Chain Reaction (PCR) method and hybridization technique were carried out using the AID kit. Results: Out of the 40 sputum samples, five (12.5%) were resistant to kanamycin/amikacin, and 12 (30%) showed resistance to streptomycin. Five mutation sites were identified in the codon 1400 of the rrs gene, which were associated with amikacin/kanamycin resistance. Additionally, nine other samples (22.5%) exhibited mutations in the Streptomycin-resistant rpsL A43G gene. Three samples (7.5%) showed mutations in the rrs C526T gene, conferring resistance to streptomycin. Conclusions: Our investigation revealed a significant frequency of resistance to drugs used as second-line medications. It must be noted that treating patients can be challenging when the frequency of multi-drug-resistant bacteria is high. [ABSTRACT FROM AUTHOR]

While the goal of universal drug susceptibility testing has been a key component of the WHO End TB Strategy, in practice, this remains inaccessible to many. Rapid molecular tests for tuberculosis (TB) and antituberculosis drug resistance could significantly improve access to testing. In this study, we evaluated the accuracy of the Akonni Biosystems XDR-TB (extensively drug-resistant TB) TruArray and lateral-flow-cell (XDR-LFC) assay (Akonni Biosystems, Inc., Frederick, MD, USA), a novel assay that detects mutations in seven genes associated with resistance to antituberculosis drugs: katG, the inhA promoter, and the ahpC promoter for isoniazid; rpoB for rifampin; gyrA for fluoroquinolones; rrs and the eis promoter for kanamycin; and rrs for capreomycin and amikacin. We evaluated assay performance using direct sputum samples from 566 participants recruited in a prospective cohort in Moldova over 2 years. The sensitivity and specificity against the phenotypic reference were both 100% for isoniazid, 99.2% and 97.9% for rifampin, 84.8% and 99.1% for fluoroquinolones, 87.0% and 84.1% for kanamycin, 54.3% and 100% for capreomycin, and 79.2% and 100% for amikacin, respectively. Whole-genome sequencing data for a subsample of 272 isolates showed 95 to 99% concordance with the XDR-LFC-reported suspected mutations. The XDR-LFC assay demonstrated a high level of accuracy for multiple drugs and met the WHO's minimum target product profile criteria for isoniazid and rifampin, while the sensitivity for fluoroquinolones and amikacin fell below target thresholds, likely due to the absence of a gyrB target in the assay. With optimization, the XDR-LFC shows promise as a novel near-patient technology to rapidly diagnose drug-resistant tuberculosis.

Background: Pseudothrombocytopenia is a commonly obtained false negative result when analyzing feline platelet count by automated machine. It is related to ethylenediamine tetra-acetic acid (EDTA), a widely utilized anticoagulant in blood collection tube, resulting in EDTA-dependent pseudothrombocytopenia (EDTA-PTCP). Aim: To investigate whether treated with kanamycin enhanced the quantity of platelet aggregations in feline blood specimens collected using EDTA-PTCP. Methods: Thirty-one blood samples were obtained using EDTA tubes. The complete blood count was analyzed using automated Mindray-BC-5000Vet. Both Manual cell counts and thin blood smears were performed to estimate the amount of RBC, WBC and platelets as well as to evaluate the severity scores of platelet clumping, respectively. Comparisons were made between those pre-treated and treated with kanamycin in EDTA tube. Results: There were significantly different mean platelet counts in the samples before and after they were treated with kanamycin, both on automated (156.6  76.4 vs 260.3  115.5; p < 0.001) and manual (168.5  92.1 vs 262.8  119.6; p < 0.001) readings, with a 95% confidence interval (CI) of 0.19 (0.022–0.365). Conclusion: This study suggests that in clinical laboratory practice, kanamycin should be added to feline blood specimens with EDTA-PTCP. [Open Vet J 2024; 14(5.000): 1199-1205]

Abstract Transforming growth factor-β (TGF-β) signaling plays a significant role in multiple biological processes, including inflammation, immunity, and cell death. However, its specific impact on the cochlea remains unclear. In this study, we aimed to investigate the effects of TGF-β signaling suppression on auditory function and cochlear pathology in mice with kanamycin-induced ototoxicity. Kanamycin and furosemide (KM-FS) were systemically administered to 8-week-old C57/BL6 mice, followed by immediate topical application of a TGF-β receptor inhibitor (TGF-βRI) onto the round window membrane. Results showed significant TGF-β receptor upregulation in spiral ganglion neurons (SGNs) after KM-FA ototoxicity, whereas expression levels in the TGF-βRI treated group remained unchanged. Interestingly, despite no significant change in cochlear TGF-β expression after KM-FS ototoxicity, TGF-βRI treatment resulted in a significant decrease in TGF-β signaling. Regarding auditory function, TGF-βRI treatment offered no therapeutic effects on hearing thresholds and hair cell survival following KM-FS ototoxicity. However, SGN loss and macrophage infiltration were significantly increased with TGF-βRI treatment. These results imply that inhibition of TGF-β signaling after KM-FS ototoxicity promotes cochlear inflammation and SGN degeneration.

The Kir4.1 channel, an inwardly rectifying potassium ion (K+) channel, is located in the hair cells of the organ of Corti as well as the intermediate cells of the stria vascularis. The Kir4.1 channel has a crucial role in the generation of endolymphatic potential and maintenance of the resting membrane potential. However, the role and functions of the Kir4.1 channel in the progenitor remain undescribed. To observe the role of Kir4.1 in the progenitor treated with the one-shot ototoxic drugs (kanamycin and furosemide), we set the proper condition in culturing Immortomouse-derived HEI-OC1 cells to express the potassium-related channels well. And also, that was reproduced in mice experiments to show the important role of Kir4.1 in the survival of hair cells after treating the ototoxicity drugs. In our results, when kanamycin and furosemide drugs were cotreated with HEI-OC1 cells, the Kir4.1 channel did not change, but the expression levels of the NKCC1 cotransporter and KCNQ4 channel are decreased. This shows that inward and outward channels were blocked by the two drugs (kanamycin and furosemide). However, noteworthy here is that the expression level of Kir4.1 channel increased when kanamycin was treated alone. This shows that Kir4.1, an inwardly rectifying potassium channel, acts as an outward channel in place of the corresponding channel when the KCNQ4 channel, an outward channel, is blocked. These results suggest that the Kir4.1 channel has a role in maintaining K+ homeostasis in supporting cells, with K+ concentration compensator when the NKCC1 cotransporter and Kv7.4 (KCNQ4) channels are deficient.

The development of highly specific biomimetic recognition material is a challenge for rapid detection of harmful residues in foodstuff. In this study, a paper-based boronate affinity metal-organic framework/molecularly imprinted polymer microfluidic chip (FZS-BA@MIP) was constructed based on the in situ construction strategy, which was also designed as a highly specific biomimetic recognition module. Here, the homogeneous zeolitic imidazole framework-8 (ZIF-8) membrane served as a great scaffold and enrichment layer. Besides, the recognition layer of MIP was prepared based on a highly oriented boronate affinity surface imprinting strategy. With the aid of the liquid flow channel, the highly specific enrichment and visual detection for antibiotic residues like kanamycin in actual products were achieved on the paper chip module of an integrated lateral flow platform. The whole analysis process could be accomplished within 30 min. In brief, this study offered a new integrated biomimetic recognition platform for visually detecting harmful veterinary residues containing cis-diols, which demonstrated promising commercial value in point-of-care testing of foodborne hazardous compounds.

To analyze the results of proficiency testing for anti-tuberculosis drug susceptibility testing (DST) in China. Number of laboratory participating the proficiency testing performed DST, and the sensitivity, specificity, reproducibility, and accordance rate were calculated from data of 13 rounds proficiency testing results for DST from 2008 to 2021. A total of 30 and 20 strains of Mycobacterium tuberculosis with known susceptibility results were sent to each laboratory in 2008 to 2019, 2020 and 2021, respectively. The number of participating laboratories ranged from 30 in 2009 to 546 in 2021. L-J DST was the predominant method. The specificity presented relatively higher than sensitivity. Improvement of specificity were observed for all drugs through the years, while sensitivity did not show improvement for amikacin and capreomycin. Accordance rate of pyrazinamide and kanamycin and reproducibility of capreomycin and pyrazinamide were not significantly improved through the years. Most of the participating laboratories significantly improved the quality of their DST through the consecutive rounds of proficiency testing except for second-line injectable drugs and pyrazinamide. The results highlight the importance of developing novel and/or improving existing methods for phenotypic DST for certain drugs. [ABSTRACT FROM AUTHOR]

Transforming growth factor-β (TGF-β) signaling plays a significant role in multiple biological processes, including inflammation, immunity, and cell death. However, its specific impact on the cochlea remains unclear. In this study, we aimed to investigate the effects of TGF-β signaling suppression on auditory function and cochlear pathology in mice with kanamycin-induced ototoxicity. Kanamycin and furosemide (KM-FS) were systemically administered to 8-week-old C57/BL6 mice, followed by immediate topical application of a TGF-β receptor inhibitor (TGF-βRI) onto the round window membrane. Results showed significant TGF-β receptor upregulation in spiral ganglion neurons (SGNs) after KM-FA ototoxicity, whereas expression levels in the TGF-βRI treated group remained unchanged. Interestingly, despite no significant change in cochlear TGF-β expression after KM-FS ototoxicity, TGF-βRI treatment resulted in a significant decrease in TGF-β signaling. Regarding auditory function, TGF-βRI treatment offered no therapeutic effects on hearing thresholds and hair cell survival following KM-FS ototoxicity. However, SGN loss and macrophage infiltration were significantly increased with TGF-βRI treatment. These results imply that inhibition of TGF-β signaling after KM-FS ototoxicity promotes cochlear inflammation and SGN degeneration. [ABSTRACT FROM AUTHOR]

Background: Pseudothrombocytopenia is a commonly obtained false negative result when analyzing feline platelet (PLT) count by an automated machine. It is related to ethylenediamine tetra-acetic acid (EDTA), a widely utilized anticoagulant in blood collection tubes, resulting in EDTA-dependent pseudothrombocytopenia (EDTA-PTCP). Aim: To investigate whether treated with kanamycin enhanced the quantity of PLT aggregations in feline blood specimens collected using EDTA-PTCP. Methods: Thirty-one blood samples were obtained using EDTA tubes. The complete blood count was analyzed using an automated Mindray BC-5000Vet. Both Manual cell counts and thin blood smears were performed to estimate the amount of red blood cell, white blood cell, and PLTs as well as to evaluate the severity scores of PLT clumping, respectively. Comparisons were made between those pre-treated and those treated with kanamycin in the EDTA tube. Results: There were significantly different mean PLT counts in the samples before and after they were treated with kanamycin, both on automated (156.6 ± 76.4 vs. 260.3 ± 115.5; p < 0.001) and manual (168.5 ± 92.1 vs. 262.8 ± 119.6; p < 0.001) readings, with a 95% confidence interval of 0.19 (0.022-0.365). Conclusion: This study suggests that in clinical laboratory practice, kanamycin should be added to feline blood specimens with EDTA-PTCP. [ABSTRACT FROM AUTHOR]

[Display omitted] An electrochemiluminescence (ECL) sensing platform for ultrasensitive and highly selective detection of kanamycin (KANA) was developed based on the prepared Ru(bpy) 3 2+-functionalized MOF (Ru@MOF) composites by hydrothermal synthesis and Ag+-dependent DNAzyme. In this sensor, the stem-loop DNA (HP) with the ferrocene (Fc) was used as substrate chain to quench the ECL emission generated by the Ru@MOF. Using the specific recognition effect between KANA and the KANA aptamer (Apt) and the DNAzyme dependence on Ag+, the KANA aptamer as the pendant strand of the DNAzyme was assembled on Ru@MOF/GCE with the aptamer. When both Ag+ and KANA were present simultaneously, KANA specifically was binded to KANA aptamer as a pendant chain. Subsequently, Ag+-dependent DNAzyme walker continuously cleaved the HP chain and released the modified end of Fc to restore the ECL signal of Ru@MOF composites, thus achieving selective and ultrasensitive detection of KANA. The constructed KANA biosensor exhibits a wide detection range (30 pM to 300 μM) accompanied by a low detection limit (13.7 pM). The KANA in seawater and milk samples are determined to evalute the practical application results of the sensor. This ECL detection strategy could be used for detecting other similar analytes and has broad potential application in biological analysis. [ABSTRACT FROM AUTHOR]

Background: Drug-resistant tuberculosis (DR-TB) is difficult to treat, and its timely diagnosis is an important factor in successful treatment outcomes. Modern technology has made it possible to diagnose DR-TB more quickly than before when it took a long time to identify the presence of resistance Mycobacterium. Objective: To evaluate the efficacy of the Xpert MTB/XDR to test the susceptibility of MTB towards anti-TB drugs by using sputum samples from infected people. Methodology: A cross-sectional study was conducted at the Programmatic Management of Drug-Resistant TB Unit (PMDT), Lady Reading Hospital, Peshawar, from March 2021 to March 2023. This study included samples from patients identified as rifampicin-resistant patients. The Xpert® MTB/XDR test's diagnosis accuracy was compared to that of the MGIT960, the reference drug susceptibility testing (DST) techniques, and the Hain Genotype® MTBDR plus and MDRsl assays (LPA). Results: The present study included 180 patients. These patients were divided into three groups for study purposes based on technique used, i.e., Pre-LPA or DST, Post-LPA, and Ten color Xpert MTB/XDR, and followed up for their culture conversion. Gene-Xpert MTB/RIF showed 93% of cases were positive, and on DST all cases showed positive results. For drug resistance in DST, LPA, and Gene-Xpert MTB/XDR, 61.1% of patients were resistant to three first-line drugs, and 11.1% were resistant to the second line. The overall median time from the identification of patients suspected of MDR-TB to the initiation of treatment in DST was 93 days. In LPA it was 25 and 5 days by Ten color Gene Xpert MTB/XDR. Conclusion: This study concludes that based on the timely initiation of treatment and culture conversion reports, DST and LPA are less efficient than the Ten-color Gene Xpert MTB/XDR assay. [ABSTRACT FROM AUTHOR]

Introduction: Streptomycin and kanamycin are aminoglycosides that are toxic to the cochlea vestibular system, can causing hearing loss. This antibiotic is used for the treatment of tuberculosis and its ototoxicity occurs in 20% of tuberculosis patients. Spirulina is a cyanobacterial species that is used as a dietary supplement and contains phycocyanin compounds that function as antioxidants and anti-inflammatory. The aim of this study was to determine the effect of spirulina on histopathological changes in the cochlea in Wistar rats after kanamycin induction. Methods: this study is a form of posttest-only controlled group design research with a sample of 24 wistar rats divided into 4 groups, namely negative control group, positive control group, treatment group 1 and treatment group 2. Observations of the study took place in November-December 2021. Histopathological measurements in hair cells, macrophages and cochlear vasculature. The analysis used non-parametric Kruskal-Wallis and post-hoc Mann-Whitney tests. Results: There were more hair cell damage, macrophage cell count, and significant vascular dilatation in the kanamycin group than in the without kanamycin group with the value p=0.001. There was significantly less number of hair cell damage in the kanamycin group with spirulina at a dose of 1000 mg than in the kanamycin group with spirulina at a dose of 400 mg p=0.045. Conclusion: There was a significant effect on the administration of spirulina on histopathological changes in the cochlea of rats. [ABSTRACT FROM AUTHOR]

The Gram-negative anaerobe Fusobacterium nucleatum is a major producer of hydrogen sulfide (H2S), a volatile sulfur compound that causes halitosis. Here, we dissected the genetic determinants of H2S production and its role in bacterial fitness and virulence in this important member of the oral microbiome. F. nucleatum possesses four enzymes, CysK1, CysK2, Hly, and MegL, that presumably metabolize l-cysteine to H2S, and CysK1 was previously shown to account for most H2S production in vitro, based on correlations of enzymatic activities with gene expression at mid-log phase. Our molecular studies showed that cysK1 and megL were highly expressed at the late exponential growth phase, concomitant with high-level H2S production, while the expression levels of the other genes remained substantially lower during all growth phases. Although the genetic deletion of cysK1 without supplementation with a CysK1-catalyzed product, lanthionine, caused cell death, the conditional ΔcysK1 mutant and a mutant lacking hly were highly proficient in H2S production. In contrast, a mutant devoid of megL showed drastically reduced H2S production, and a cysK2 mutant showed only minor deficiencies. Intriguingly, the exposure of these mutants to various antibiotics revealed that only the megL mutant displayed altered susceptibility compared to the parental strain: partial sensitivity to nalidixic acid and resistance to kanamycin. Most significantly, the megL mutant was attenuated in virulence in a mouse model of preterm birth, with considerable defects in the spread to amniotic fluid and the colonization of the placenta and fetus. Evidently, the l-methionine γ-lyase MegL is a major H2S-producing enzyme in fusobacterial cells that significantly contributes to fusobacterial virulence and antibiotic susceptibility. IMPORTANCE Fusobacterium nucleatum is a key commensal anaerobe of the human oral cavity that plays a significant role in oral biofilm development and contributes to additional pathologies at extraoral sites, such as promoting preterm birth and colorectal cancer. Although F. nucleatum is known as a major producer of hydrogen sulfide (H2S), its genetic determinants and physiological functions are not well understood. By a combination of bacterial genetics, biochemical methods, and in vivo models of infection, here, we demonstrate that the l-methionine γ-lyase MegL not only is a major H2S-producing enzyme of F. nucleatum but also significantly contributes to the antibiotic susceptibility and virulence of this organism.

Objective(s): The protection of spiral ganglion neurons (SGNs) is crucial for hearing loss. Exendin-4 has been shown to have neuroprotective effects in several neurological disorders. Therefore, this study aimed to investigate the effect of the glucagon-like protein-1 receptor (GLP-1R) agonist exendin-4 on kanamycin-induced injury in mouse SGNs in vitro.Materials and Methods: In this study, GLP-1R expression in SGNs was verified by immunofluorescence and immunohistochemical staining. In vitro-cultured SGNs and the organ of Corti were exposed to kanamycin with or without exendin-4 treatment. The cell survival rate was measured using the cell counting kit-8 assay, and the damage to auditory nerve fibers (ANF) projecting radially from the SGNs was evaluated using immunofluorescence staining. Reactive oxygen species (ROS) content was determined by flow cytometry, and glutathione peroxidase (GSH-Px) content, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) content were determined by spectrophotometry. Protein expression of nuclear factor erythroid-2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) was detected using western blotting.Results: GLP-1R was expressed in SGNs. Treatment with 1 mM kanamycin for 24 hr induced SGN damage. Exendin-4 (100 nM) had a protective effect against kanamycin-induced SGN cell injury, improved cell survival rate, reduced nerve fiber injury, increased SOD activity and GSH-Px level, and reduced MDA and ROS contents. The Nrf2/HO-1 pathway was activated.Conclusion: Exendin-4 alleviates oxidative damage and exerts neuroprotective effects in kanamycin-induced SGN injury through the Nrf2/HO-1 signaling pathway. Exendin-4 has the potential to prevent or treat hearing loss due to SGN damage.

Aptamer-based lateral flow analysis (Apt-LFAs) has promising applications in many fields. Nanozymes have demonstrated high potential in improving the performance of Apt-LFAs and have been increasingly utilized in recent studies. In this study, we developed a nanozyme-based Apt-LFA for the rapid and sensitive detection of kanamycin by using a novel dual-functionalized AuNPs@polyA-DNA/GpG-Cu2+ nanozyme as a nanoprobe. In the nanoprobe design, the polyA-cDNA strand can discriminate a kanamycin aptamer from the kanamycin/aptamer complex, and the GpG-Cu2+ complex can amplify the detection signal by catalyzing the chromogenic reaction. The nanozyme Apt-LFA can quantify kanamycin in the range of 1–250 ng/mL with an LOD of 0.08 ng/mL, which demonstrated a 4-fold sensitivity improvement and had a wider linear range than the conventional AuNP-based LFA. The Apt-LFA was successfully applied to the detection of kanamycin in honey with good recoveries. Our dual-functionalized AuNP nanoprobe is easily prepared and can be highly compatible with the conventional AuNP-DNA-based LFA platform; thus, it can be extended to the application of Apt-LFAs for other small molecules.

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The synthesis and characterization of two new porphyrin-based porous organic polymers (POPs) via Sonogashira cross-coupling reaction and leverage the two obtained POPs is reported for the fabrication of electrochemical aptasensors to detect kanamycin at an ultratrace level. The resultant electrochemical aptasensor demonstrates a high linear relationship with the logarithmic value of kanamycin concentration in the range 5 × 10−5–5 μg/L with the limit of detection of 17.6 pg/L or 36.3 fM. During the analysis of real samples from milk and river, a relative standard deviation of less than 4.39%, and good recovery values in the range 97.0–105% were obtained. [ABSTRACT FROM AUTHOR]

Some of the wound dressings on the market cause skin tearing and bleeding when removed, slowing the healing process. So, it is difficult to treat infected wounds of sensitive skin patients. Herein, antibacterial and biocompatibility self-healing hydrogel loaded with 9-Aminoacridine and kanamycin sulfate were prepared by grafting poly(β-carboxyethyl acrylate-co-acrylamide) onto sodium alginate. The biological assay demonstrated the hydrogels' good biocompatibility, which showed no harmful effects on normal human melanocyte cells. In addition, the hydrogels had a powerful antibacterial impact on the various bacterial strains utilized in the investigation. From the study of the rheological properties of the prepared hydrogel, it was found that it is a non-Newtonian fluid. These results suggest the possible utilization of the as-prepared hydrogels in the fabrication of wound healing. [ABSTRACT FROM AUTHOR]

Paraffinoma of the penis, also known as sclerosing lipogranuloma of the penis, represents a foreign body reaction in response to the subcutaneous injection of liquid paraffin, silicon, professional-grade oil, mineral oil, kanamycin, and various others, with the aim of increasing penile girth. Liquid paraffin is the most commonly used substance. We present the case of a patient who presented with lesions suggestive of a diagnosis of penile paraffinoma, occurring after the injection of ointment containing kanamycin, with the goal of increasing penis size. The most important criterion for establishing a positive diagnosis is the personal history of self-injection. Histopathological examination, along with clinical and paraclinical findings, serve as complementary examinations, useful for the diagnosis of certainty. Lesions can appear from weeks to several years after injection, with the most common complications being erectile dysfunction, inguinal adenopathies, superinfections, local migration of the injected substance, invasion of the corpora cavernosa, acute urinary retention, urinary disturbances, phimosis, paraphimosis, epidermoid carcinoma. Treatment options include conservative or surgical approaches, close monitoring of the patients being essential due to the risk of recurrence. [ABSTRACT FROM AUTHOR]

An ultrasensitive photoelectrochemical (PEC) aptasensor was originally designed by using ZnIn2S4/ReS2 as a photoactive material and AgInS2 as a signal amplifier. The signal amplifier AgInS2 was incubated on the terminal of H-DNA (immobilized on the ZnIn2S4/ReS2/FTO surface), leading to an enhanced photocurrent response. Then, due to the introduction of DNA2, the formation of a double-stranded structure caused AgInS2 to keep away from the electrode surface, and the photocurrent was reduced. In the presence of kanamycin, DNA2 was released from the system due to the competition relationship, and a restored photocurrent response was obtained. The combination of ZnIn2S4/ReS2 and AgInS2 accelerated the electron transfer and enhanced the separation efficiency of photogenerated electron–hole pairs, resulting in an improved performance of the PEC aptasensor, which was capable of accurate and sensitive detection of kanamycin in actual samples. [ABSTRACT FROM AUTHOR]

The Kir4.1 channel, an inwardly rectifying potassium ion (K+) channel, is located in the hair cells of the organ of Corti as well as the intermediate cells of the stria vascularis. The Kir4.1 channel has a crucial role in the generation of endolymphatic potential and maintenance of the resting membrane potential. However, the role and functions of the Kir4.1 channel in the progenitor remain undescribed. To observe the role of Kir4.1 in the progenitor treated with the one-shot ototoxic drugs (kanamycin and furosemide), we set the proper condition in culturing Immortomouse-derived HEI-OC1 cells to express the potassium-related channels well. And also, that was reproduced in mice experiments to show the important role of Kir4.1 in the survival of hair cells after treating the ototoxicity drugs. In our results, when kanamycin and furosemide drugs were cotreated with HEI-OC1 cells, the Kir4.1 channel did not change, but the expression levels of the NKCC1 cotransporter and KCNQ4 channel are decreased. This shows that inward and outward channels were blocked by the two drugs (kanamycin and furosemide). However, noteworthy here is that the expression level of Kir4.1 channel increased when kanamycin was treated alone. This shows that Kir4.1, an inwardly rectifying potassium channel, acts as an outward channel in place of the corresponding channel when the KCNQ4 channel, an outward channel, is blocked. These results suggest that the Kir4.1 channel has a role in maintaining K+ homeostasis in supporting cells, with K+ concentration compensator when the NKCC1 cotransporter and Kv7.4 (KCNQ4) channels are deficient. [ABSTRACT FROM AUTHOR]

Aminoglycoside antibiotics represent the first class of successful drugs in the treatment of tuberculosis; however, mycobacteria and other bacterial species possess several drug resistance mechanisms to inactivate these natural products. In the past 15 years, a variety of amphiphilic aminoglycosides have been shown to have improved activity against infectious microorganisms and to subvert resistance mechanisms. Here, we report on four novel synthetic compounds derived from two existing potent antitubercular compounds and describe their activity against both Mycobacterium tuberculosis and Staphylococcus aureus. It was found that a decanesulfonylacetamidebased conjugate of amikacin displayed promising preliminary antitubercular activities, warranting further investigation to assess the therapeutic potential of these unique antimicrobials. [ABSTRACT FROM AUTHOR]

The overuse and abuse of antibiotics have led to increased pollution in water environments. Thus, it is crucial to develop a rapid, high-frequency, and cost-effective method for on-site detection of antibiotics. In this regard, a reusable fiber-embedded microfluidic chip was constructed by combining a microfluidic chip with a functionalized fiber bioprobe that served as both a biorecognition element and an optical transducer. The fiber-embedded microfluidic chip enabled the quantitative detection of kanamycin (KANA) by integrating a portable all-fiber evanescent wave fluorescence detection device. Under optimized conditions, quantitative KANA detection was achieved with a detection limit of 0.03 μg L−1 and a linear detection range of 0.21–10.3 μg L−1. The accurate detection of KANA in various water samples can be completed within 25 min without pretreatment. The functionalized fiber-embedded microfluidic chip could be reused more than 200 times without significant performance loss. To demonstrate its suitability for practical applications, the fiber-embedded microfluidic chip was used to investigate KANA residues in surface waters obtained from the Qinghe River in Beijing, China. The results were compared with those of a traditional enzyme-linked immunosorbent assay, which showed a high correlation. Compared to conventional optical microfluidic chips, the proposed fiber-embedded microfluidic chip has several advantages, including its ease of use, miniaturization, cost-effectiveness, reusability, and high flexibility. It is an ideal alternative for rapid, sensitive on-site detection of antibiotics and other trace substances in environmental, food, and medical fields. [ABSTRACT FROM AUTHOR]

A highly active G4 DNAzyme-peptide complex obtained by covalent assembly of cationic peptide on G4 DNAzyme was used to construct a novel electrochemical aptasensor. The effect of complex on the performance of electrochemical aptasensor was investigated and the proposed aptasensor was used to detect kanamycin (KANA) in milk. The experimental results indicated that G4 DNAzyme-peptide could significantly amplify the electrochemical signal and greatly improve the detection sensitivity of aptasensor. Under the optimal concentration of capture probe (CP, 2.0 µmol/L), the change of current intensity showed a good linear relationship with the logarithm of the target concentration in the range of 0.06 pmol/L~20 nmol/L, and the detection limit was 0.02 pmol/L, which was superior to other KANA detection methods. The aptasensor showed better selectivity and lower detection limit and the recoveries obtained in milk sample were from 97.1% to 105.5% and the relative standard deviation were from 3.60% to 5.74%. The experimental results were consistent with ELISA method, indicating the proposed aptasensor could achieve high sensitivity for the detection of KANA in milk. [ABSTRACT FROM AUTHOR]

Background: Agrobacterium mediated genetic transformation experiments were carried out in Dolichos bean Cv. (Konkan Bhushan) showing better regenerability. Methods: Three cry genes viz. cry1Aabc, cry1Fa1 and cry2Aa were used for the transformation each of which were linked to CaMV35S promoter and nptII gene under control of nos promoter and terminator. A vector system consisting of the disarmed hyper virulent Agrobacterium tumefaciens strain EHA-105 harboring pBinAR or BinBt3 was used. Mature embryo axis with single cotyledon was used as explant. Kanamycin as well as PCR screening was carried out to assess the transformation frequency. Progeny analysis using PCR was also carried out to assess the transgene segregation and stable transformation. Result: Kanamycin concentration of 500 mg/l was found as optimum for selection of a transgenic turning leaf blades albino. Among five methods of colonization used, the method employing mild injury to explant with dipping in Agrobacterium culture for 20 minutes followed by co-cultivation for 48 hours, cefotaxime washing and sowing in soil resulted in maximum survival (74.80%) associated with maximum transformation frequency through PCR analysis (2.13%). Among three cry genes, the gene cry2Aa was found the most effective in transforming Dolichos bean. The progeny analysis of transformants has shown the 3:1 mendelian segregation ratio confirming stable transformation of transgene. [ABSTRACT FROM AUTHOR]