Inhibitory Concentration Of Drug Research Articles

Attomole-per Cell Atomic Mass Spectrometry Measurement of Platinum and Gold Drugs in Cultured Lung Cancer Cells.

In this study, we developed a strategy to determine atto- and femtomolar amounts of metal ions in lysates and mineralizates of cells (human non-small-cell lung carcinoma (NSCLC, A549) and normal lung (MRC-5)) exposed to cytotoxic metallo-drugs: cisplatin and auranofin at concentrations close to the half-maximal inhibitory drug concentrations (IC50). The developed strategy combines data obtained using biological and chemical approaches. Cell density was determined using two independent cell staining assays using trypan blue, calcein AM/propidium iodide. Metal concentrations in lysed and mineralized cells were established employing a mass spectrometer with inductively coupled plasma (ICP-MS) and equipped with a cross-flow nebulizer working in aspiration mode. It allowed for detecting of less than 1 fg of metal per cell. To decrease the required amount of sample material (from 1.5 mL to ~100 µL) without loss of sensitivity, the sample was introduced as a narrow band into a constant stream of liquid (flow-injection analysis). It was noticed that the selectivity of cisplatin accumulation by cells depends on the incubation time. This complex is accumulated by cells at a lower efficiency than auranofin and is found primarily in the lysate representing the cytosol. In contrast, auranofin interacts with water-insoluble compounds. Despite their different mechanism of action, both metallo-drugs increased the accumulation of transition metal ions responsible for oxidative stress.

In Vitro Killing of Canine Urinary Tract Infection Pathogens by Ampicillin, Cephalexin, Marbofloxacin, Pradofloxacin, and Trimethoprim/Sulfamethoxazole.

Urinary tract infections are common in dogs, necessitating antimicrobial therapy. We determined the speed and extent of in vitro killing of canine urinary tract infection pathogens by five antimicrobial agents (ampicillin, cephalexin, marbofloxacin, pradofloxacin, and trimethoprim/sulfamethoxazole) following the first 3 h of drug exposure. Minimum inhibitory and mutant prevention drug concentrations were determined for each strain. In vitro killing was determined by exposing bacteria to clinically relevant drug concentrations and recording the log10 reduction and percent kill in viable cells at timed intervals. Marbofloxacin and pradofloxacin killed more bacterial cells, and faster than other agents, depending on the time of sampling and drug concentration. Significant differences were seen between drugs for killing Escherichia coli, Proteus mirabilis, Enterococcus faecalis, and Staphylococcus pseudintermedius strains. At the maximum urine drug concentrations, significantly more E. coli cells were killed by marbofloxacin than by ampicillin (p < 0.0001), cephalexin (p < 0.0001), and TMP/SMX (p < 0.0001) and by pradofloxacin than by cephalexin (p < 0.0001) and TMP/SMX (p < 0.0001), following 5 min of drug exposure. Rapid killing of bacteria should inform thinking on drug selection for short course therapy for uncomplicated UTIs, without compromising patient care, and is consistent with appropriate antimicrobial use and stewardship principles.

Clinical M2 macrophages-related genes to aid therapy in pancreatic ductal adenocarcinoma

BackgroundIncreasing evidence supports that infiltration M2 Macrophages act as pivotal player in tumor progression of pancreatic ductal adenocarcinoma (PDAC). Nonetheless, comprehensive analysis of M2 Macrophage infiltration and biological roles of hub genes (FAM53B) in clinical outcome and immunotherapy was lack.MethodThe multiomic data of PDAC samples were downloaded from distinct datasets. CIBERSORT algorithm was performed to uncover the landscape of TIME. Weighted gene co-expression network analysis (WGCNA) was performed to identify candidate module and significant genes associated with M2 Macrophages. Kaplan-Meier curve and receiver operating characteristic (ROC) curves were applied for prognosis value validation. Mutation data was analyzed by using “maftools” R package. Gene set variation analysis (GSVA) was employed to assign pathway activity estimates to individual sample. Immunophenoscore (IPS) was implemented to estimate immunotherapeutic significance of risk score. The half-maximal inhibitory concentration (IC50) of chemotherapeutic drugs was predicted by using the pRRophetic algorithm. Finally, quantitative real-time polymerase chain reaction was used to determine FAM53B mRNA expression and TIMER database was utilized to uncover its possible role in immune infiltration of PDAC.ResultsHerein, 17,932 genes in 234 samples (214 tumor and 20 normal) were extracted from three platforms. Taking advantage of WGCNA, significant module (royalblue) and 135 candidate genes were considered as M2 Macrophages-related genes. Subsequently, risk signature including 5 hub genes was developed by multiple analysis, which exhibited excellent prognostic performance. Besides, comprehensive prognostic nomogram was constructed to quantitatively estimate risk. Then, intrinsic link between risk score with tumor mutation burden (TMB) was explored. Additionally, risk score significantly correlated with diversity of tumor immune microenvironment (TIME). PDAC samples within different risk presented diverse signaling pathways activity and experienced significantly distinct sensitivity to administering chemotherapeutic or immunotherapeutic agents. Finally, the biological roles of FAM53B were revealed in PDAC.ConclusionsTaken together, comprehensive analyses of M2 Macrophages profiling will facilitate prognostic prediction, delineating complexity of TIME, and contribute insight into precision therapy for PDAC.

Bioinformatics analysis based on immune-autophagy-related lncRNAs combined with immune infiltration in bladder cancer.

BackgroundTo construct a prognostic model based on immune-autophagy-related long noncoding RNA (IArlncRNAs), mainly to predict the overall survival rate (OS) of bladder cancer patients and investigate its possible mechanisms.MethodsTranscriptome and clinical data were obtained from The Cancer Genome Atlas (TCGA) database. We identified the IArlncRNA by co-expression analysis, differential expression analysis, and Venn analysis. Then, we identified the independent prognostic IArlncRNAs by univariate Cox regression, LASSO regression, and multivariate Cox regression analysis. Moreover, we constructed the prognostic model based on the independent prognostic IArlncRNAs and clinical features. The proportion of 22 immune cell subtypes was analyzed by the CIBERSORT algorithm. Besides, we identified the differential proportion of 22 immune cell subtypes between the high- and low-risk groups. In addition, we identified the correlation between immune-infiltrating cells (screened by univariate Cox regression and multivariate Cox regression analysis) and IArlncRNAs by Pearson correlation analysis. Finally, we estimated the half-maximal inhibitory concentration (IC50) of chemotherapeutic drugs in patients with bladder cancer based on the pRRophetic algorithm.ResultsFour IArlncRNAs were identified as independent prognostic factors, including AL136084.3, AC006270.1, Z84484.1, and AL513218.1. The OS of patients in the high-risk group was significantly worse compared to the low-risk group. The nomogram showed an excellent predictive effect with the C-index of 0.64. The calibration chart showed a good actual vs. predicted probability. B cells naïve, T cells CD8, T cells CD4 memory resting, T cells follicular helper, macrophages M1, dendritic resting and activated cells had higher infiltrations in the low-risk group and lower infiltration of macrophages M2. The fraction of macrophages M2 was positively associated with AL136084.3. The fraction of T cells CD8 was positively associated with Z84484.1. The fraction of M + macrophages M0 was negatively associated with Z84484.1. Further, we identified the differential IC50 of 24 chemotherapeutic drugs between the high- and low-risk groups.ConclusionsThe prognostic model based on 4 IArlncRNAs showed an excellent predictive effect. Furthermore, we reasonably speculated that IArlncRNAs are directly or indirectly involved in the immune regulation of the tumor microenvironment (TME), as well as autophagy.

Development of a molecular biological assay for the detection of markers related to decreased susceptibility to macrolides and lincomycin in Mycoplasma hyorhinis.

The control of Mycoplasma hyorhinis infection relies mainly on antimicrobial therapy. However, the antibiotic susceptibility testing of the bacteria is usually not performed before applying the treatment, and thus therapeutic failures are not uncommon. In the case of M. hyorhinis, several antibiotic-resistance-related single nucleotide polymorphisms (SNPs) are known but assays for their detection have not been described yet. The aims of the present study were to investigate macrolide- and lincomycin-resistance-related SNPs in Hungarian M. hyorhinis isolates and to develop mismatch amplification mutation assays (MAMA) to detect the identified resistance markers. Minimal inhibitory concentrations (MIC) of different drugs and whole genome sequences of 37 M. hyorhinis isolates were used to find the resistance-related mutations. One MAMA assay was designed to detect the mutation of the 23S rRNA gene at nucleotide position 2058 (Escherichia coli numbering). For further evaluation, the assay was challenged with 17 additional isolates with available MIC data and 15 DNA samples from clinical specimens. The genotypes of the samples were in line with the MIC test results. The developed assay supports the practice of targeted antibiotic usage; hence it may indirectly reduce some bacterial resistance-related public health concerns.

Design of Multidrug-Resistant Tuberculosis Treatment Regimens Based on DNA Sequencing.

Comprehensive and reliable drug susceptibility testing (DST) is urgently needed to provide adequate treatment regimens for patients with multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB). We determined whether next-generation sequencing (NGS) analysis of Mycobacterium tuberculosis complex isolates and genes implicated in drug resistance can guide the design of effective MDR/RR-TB treatment regimens. NGS-based genomic DST predictions of M. tuberculosis complex isolates from MDR/RR-TB patients admitted to a TB reference center in Germany between 1 January 2015 and 30 April 2019 were compared with phenotypic DST results of mycobacteria growth indicator tubes (MGIT). Standardized treatment algorithms were applied to design individualized therapies based on either genomic or phenotypic DST results, and discrepancies were further evaluated by determination of minimal inhibitory drug concentrations (MICs) using Sensititre MYCOTBI and UKMYC microtiter plates. In 70 patients with MDR/RR-TB, agreement among 1048 pairwise comparisons of genomic and phenotypic DST was 86.3%; 76 (7.2%) results were discordant, and 68 (6.5%) could not be evaluated due to the presence of polymorphisms with yet unknown implications for drug resistance. Importantly, 549 of 561 (97.9%) predictions of drug susceptibility were phenotypically confirmed in MGIT, and 27 of 64 (42.2%) false-positive results were linked to previously described mutations mediating a low or moderate MIC increase. Virtually all drugs (99.0%) used in combination therapies that were inferred from genomic DST were confirmed to be susceptible by phenotypic DST. NGS-based genomic DST can reliably guide the design of effective MDR/RR-TB treatment regimens.

Whole Genome Sequencing for Surveillance of Tuberculosis Drug Resistance in China: Based on a Cross-Sectional Surveillance Study

Background: Phenotypic drug susceptibility testing for prediction of tuberculosis (TB) drug resistance is slow and unreliable, limiting individualized therapy and monitoring of national TB data. Our study evaluated whole genome sequencing (WGS) for its predictive accuracy, use in TB drug-resistance surveillance, and ability to quantify the effects of resistance-associated mutations on minimum inhibitory concentrations (MICs) of anti-TB drugs. Methods: We used WGS to measure the susceptibility of 4880 isolates to ten anti-TB drugs ; for pyrazinamide, we used BACTEC MGIT 960. We determined the accuracy of WGS by comparing the prevalence of resistance, measured by genetic sequencing, with the true prevalence of resistance, determined by phenotypic testing. We used the Student-Newman-Keuls test to confirm MIC differences of mutations. Findings: Resistance to isoniazid, rifampin, and ethambutol were correctly predicted with at least 92·29% sensitivity, resistance to pyrazinamide with 50·52% sensitivity, and resistance to six second-line drugs with 85·05% to 96·01% sensitivity. In addition to the large overlap in estimated drug resistance prevalence by WGS and phenotypic testing, WGS can detect low-level resistant or sub-ECOFF mutations which may be missed by phenotyping. For nearly all drugs, resistance-conferring mutations had varying levels of impact on MICs. Interpretation: WGS can predict phenotypic susceptibility with high accuracy and allow for detection of new escape mutations by rapid molecular tools; as such, it can be a valuable tool in TB drug resistance surveillance and for determining the therapeutic approach. Funding Information: We acknowledge the financial supports of the grants from the Ministry of Science and Technology, the National Science and Technology Major Project (2018ZX10103001) and the National Key Research and Development Plan (No. 2020YFA0907200, 2019YFC0840602). Declaration of Interests: All authors report no conflicts of interest relevant to this article.

Molecular typing and antifungal drug susceptivity profile of Rhodotorula mucilaginosa from canine skin and ear canal.

Rhodotorula mucilaginosa are saprophytic yeast, and opportunistic infections known as human rhodotorulosis are increasing in immunocompromised patients. In this study, we isolated R. mucilaginosa from pet dogs in Japan and determined the minimum inhibitory concentrations (MICs) of antifungal drugs on these isolates to investigate the drug susceptibility pattern. All 10 isolates according to the broth microdilution (BM) assay of the Clinical and Laboratory Standards Institute (CLSI) M27-A2 were resistance to azoles and genetically close to fluconazole (FLZ)-resistant human isolates of R. mucilaginosa. Due to resistance, it is expected that treatment will be difficult if they infect humans.

Identification of a Tumor Microenvironment-Related Gene Signature Indicative of Disease Prognosis and Treatment Response in Colon Cancer.

Background The tumor microenvironment (TME) is associated with disease outcomes and treatment response in colon cancer. Here, we constructed a TME-related gene signature that is prognosis of disease survival and may predict response to immunotherapy in colon cancer. Methods We calculated immune and stromal scores for 385 colon cancer samples from The Cancer Genome Atlas (TCGA) database using the ESTIMATE algorithm. We identified nine TME-related prognostic genes using Cox regression analysis. We evaluated associations between protein expression, extent of immune cell infiltrate, and patient survival. We calculated risk scores and built a clinical predictive model for the TME-related gene signature. Receiver operating characteristic (ROC) curves were generated to assess the predictive power of the signature. We estimated the half-maximal inhibitory concentration (IC50) of chemotherapeutic drugs in patients using the pRRophetic algorithm. The expression of immune checkpoint genes was evaluated. Results High immune and stromal scores are significantly associated with poor overall survival (p < 0.05). We identified 773 differential TME-related prognostic genes associated with survival; these genes were enriched in immune-related pathways. Nine key prognostic genes were identified and were used to construct a TME-related prognostic signature: CADM3, LEP, CD1B, PDE1B, CCL22, ABI3BP, IGLON5, SELE, and TGFB1. This signature identified a high-risk group with worse survival outcomes, based on Kaplan-Meier analysis. A nomogram composed of clinicopathological factors and risk score exhibited good accuracy. Drug sensitivity analysis identified no difference in sensitivity between the high-risk and low-risk groups. High-risk patients had higher expression of PD-1, PDL-1, and CTLA-4 and lower expression of LAG-3 and VSIR. Infiltration of dendritic cells was higher in the high-risk group. Conclusions We identified a novel prognostic TME-related gene expression signature in colon cancer. Stratification of patients based on this gene signature could be used to improve outcomes and guide better therapy for colon cancer patients.

Isolation of antifungal-resistant yeasts from bulk milk in Japan.

We isolated ascomycetous yeasts including Candida species, that originally belonged to the genus Candida, from bulk milk in the Aichi area of Japan, and determined the minimum inhibitory concentrations (MICs) of antifungal drugs on these isolates by conducting E-tests. We isolated 7 human pathogenic species (14 isolates) from 14 bulk milk samples: 5 Candida species of yeasts, and 2 Candida-related species. Two isolates of C. albicans and C. inconspicua were resistant to fluconazole (MIC >32 mg/l). One isolate of C. krusei was resistant to both azoles (fluconazole: >256 mg/ml and itraconazole: 4 mg/l). One isolate of C. catenulata might be resistant to amphotericin B (>32 mg/l).

Potential Role of Proteasome Accessory Factor-C in Resistance against Second Line Drugs in Mycobacteria.

Objectives Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis (TB), can survive inside the host granuloma courtesy the various extrinsic and intrinsic factors involved. Continuous use or misuse of the anti TB drugs over the years has led to the development of resistance in MTB against antibiotics. Drug-resistant TB in particular has been a menace since treating it requires exposing the patient to drugs for a prolonged period of time. Multidrug-resistant (MDR) and extensively drug resistant TB cases have increased over the years mostly due to the exposure of MTB to suboptimal levels of drug. Proteasomes provide MTB its pathogenicity and hence helps it to survive inside the host even in the presence of drugs. Materials and Methods The recombinantly expressed proteasome accessory factor-C (PafC) protein was purified via Ni-NTA affinity chromatography and overexpressed in the nonpathogenic strain of mycobacteria (Mycobacterium smegmatis) for the comparative analysis of minimum inhibitory concentrations of antimycobacterial drugs. The bacteria were subjected to various stress conditions. Secretory nature of PafC was analyzed by probing the purified protein against patient sera. Quantitative mRNA analysis of paf C, lex A, and rec A was performed to check for their level under fluoroquinolone (FQ) presence. The data were validated in clinical samples of pulmonary TB patients. Results pafC , that forms one part of paf operon, is involved in providing MTB its resistance against FQs. Through a series of experiments, we established the fact that PafC is upregulated in mycobacteria upon exposure to FQs and it leads to the increased intracellular survival of mycobacteria under the stresses generated by FQs. The study also refers to the correlation of pafC to deoxyribonucleic acid (DNA) damage repair enzymes lexA and recA at transcriptional level. The results obtained in vitro corroborated when the pulmonary TB patients’ samples were subjected to the same molecular analysis. Statistical Analysis All experiments were conducted at least in triplicate. p -Value of <0.05 was considered to be statistically significant Conclusion PafC plays a significant role in providing resistance to mycobacteria against FQ class of drugs by increasing its intracellular survival through increased drug efflux and getting involved with DNA damage repair machinery.

Effects of cigarette smoke on the administration of isoniazid and rifampicin to macrophages infected with Mycobacterium tuberculosis

Background Smoking is a cause behind many diseases, including tuberculosis, and it is a risk factor for tuberculosis infection and mortality. Moreover, smoking is associated with a poor tuberculosis treatment outcome. Objectives In this study, we focus on the effects of cigarette smoke on an infected cell culture treated with anti-tuberculosis drugs. Materials and methods Cytotoxicity on THP-1, J774A.1 and MH-S cell lines and growth of Mycobacterium tuberculosis exposed to a reference or a commercial cigarette was evaluated. THP-1 cell line was exposed to cigarette smoke, infected with Mycobacterium tuberculosis and treated with anti-tuberculosis drugs. Apoptosis and death cell were also tested on M. bovis BCG infected cells. Minimal inhibitory concentrations of anti-tuberculosis drugs were analyzed. Results All cells lines showed viability values higher than 80% when exposed to cigarette smoke extract. However, THP-1 cell line infected with M. bovis BCG and exposed to Marlboro cigarette smoke showed up to a 54% reduction of apoptotic cells than cells unexposed to smoke. M. tuberculosis exposed to Marlboro cigarette smoke for 11 days had an optical density 16% lower than unexposed bacteria. When cells were infected with M. tuberculosis, the intracellular recovery of CFUs showed up to a 0.66 log reduction in cells exposed to cigarette smoke extract because of a potential impairment in the phagocytosis. Macrophages treated with drugs showed up to a 2.55 log reduction in the intracellular load burden compared with non-treated ones. Despite poor treatment outcome on TB smoker patients, minimal inhibitory concentration of rifampicin increased only 2-fold in M. tuberculosis exposed to cigarette smoke. Conclusion Smoking interferes with tuberculosis treatment impairing the immunity of the host.

Potentiation of antifungal activity of terbinafine by dihydrojasmone and terpinolene against dermatophytes.

Dermatophytoses are infections that affect keratinized tissues. Their main etiologic agents are fungi of the genera Microsporum and Trichophyton. The emergence of resistant fungi and the clinical relevance of dermatophytosis have encouraged studies that aim to increase the arsenal of drugs or act on mechanisms that confer multiple drug resistance. This study investigated the modulating activity of terbinafine promoted by dihydrojasmone and terpinolene against Microsporum canis LM 216, Trichophyton interdigitale H6 and T. interdigitale Δmdr2. The minimum inhibitory concentration (MIC) of test drugs was determined by broth microdilution. The effect of the drugs tested on plasma membrane functionality was analysed. Terbinafine MIC was determined in sub-inhibitory concentrations of monoterpenes. Finally, it was performed an association study with terbinafine and monoterpenes. Dihydrojasmone presented lower MIC values than terpinolene. All fungi were sensitive to terbinafine, starting at 1μgml-1 . All tested drugs increased K+ release (P<0·05), affecting the functionality of the plasma membrane. Dihydrojasmone modulated the sensitivity of all strains against terbinafine, and terpinolene modulated the sensitivity of M. canis LM 216 and T. interdigitale Δmdr2. The monoterpenes and terbinafine drug associations presented synergism. In conclusion, the results suggest that the dihydrojasmone and terpinolene are promising antifungal agents that potentiate the antifungal activity of terbinafine against dermatophytes.

Combatting fungal biofilm formation by diffusive release of fluconazole from heptylamine plasma polymer coating.

A drug-eluting coating applied onto biomedical devices and implants is an appropriate way to ensure that an inhibitory concentration of antimicrobial drugs is present at the device surface, thus preventing surface colonization and subsequent biofilm formation. In this study, a thin polymer coating was applied to materials, and it acted as a drug-delivery reservoir capable of surface delivery of the antifungal drug fluconazole to amounts up to 21 μg/cm2. The release kinetics into aqueous solution were quantified by UV spectroscopy and conformed to the Ritger-Peppas and Korsmeyer-Peppas model. Complementary microbiological assays were used to determine effectiveness against Candida albicans attachment and biofilm formation, and against the control heptylamine plasma polymer coating without drug loading, on which substantial fungal growth occurred. Fluconazole release led to marked antifungal activity in all assays, with log 1.6 reduction in CFUs/cm2. Cell viability assays and microscopy revealed that fungal cells attached to the fluconazole-loaded coating remained rounded and did not form hyphae and biofilm. Thus, in vitro screening results for fluconazole-releasing surface coatings showed efficacy in the prevention of the formation of Candida albicans biofilm.

Time-Resolved Studies of Bioluminescence From Photobacterium Leiognathi and Rapid Antimicrobial Susceptibility Testing on E. Coli Using Tunable Diode Laser Spectroscopy

We demonstrate that tunable diode laser spectroscopy (TDLS) can be used as a reliable, convenient and versatile investigative technique for non-invasive, high-sensitivity and time-resolved studies of the expression of various traits by bacterial strains. We use a 2004 nm vertical cavity surface emitting laser and a 4320 nm mid-infrared quantum cascade laser to show that the bioluminescence and simultaneous CO2 emission from Photobacterium leiognathi are correlated. The bioluminescence peaks when the growth rate is maximum. This supports the hypothesis that bioluminescence is a cell density-dependent phenomenon. We also show that TDLS can be used for ultra-rapid antimicrobial susceptibility testing without any need of sample preparation. The mole fraction of CO2 emitted during the growth of E. coli was recorded for different standardized doses of ampicillin to show the drastic suppression of growth as the antibiotic dose was increased to the recommended minimum inhibitory drug concentration. Growth suppression was detectable within 2 h, which is much shorter than the time required by conventional methods. We conclude that TDLS is a potent technique for validation and refinement of mathematical models of microbial growth that are necessary to better understand the dynamics of the expression of various traits at specific stages of growth. It is also important for rapid antimicrobial susceptibility testing.

Distribution, antifungal susceptibility pattern and intra-Candida albicans species complex prevalence of Candida africana: A systematic review and meta-analysis.

Candida africana is a pathogenic species within the Candida albicans species complex. Due to the limited knowledge concerning its prevalence and antifungal susceptibility profiles, a comprehensive study is overdue. Accordingly, we performed a search of the electronic databases for literature published in the English language between 1 January 2001 and 21 March 2020. Citations were screened, relevant articles were identified, and data were extracted to determine overall intra-C. albicans complex prevalence, geographical distribution, and antifungal susceptibility profiles for C. africana. From a total of 366 articles, 41 were eligible for inclusion in this study. Our results showed that C. africana has a worldwide distribution. The pooled intra-C. albicans complex prevalence of C. africana was 1.67% (95% CI 0.98-2.49). Prevalence data were available for 11 countries from 4 continents. Iran (3.02%, 95%CI 1.51-4.92) and Honduras (3.03%, 95% CI 0.83-10.39) had the highest values and Malaysia (0%) had the lowest prevalence. Vaginal specimens were the most common source of C. africana (92.81%; 155 out of 167 isolates with available data). However, this species has also been isolated from cases of balanitis, from patients with oral lesions, and from respiratory, urine, and cutaneous samples. Data concerning the susceptibility of C. africana to 16 antifungal drugs were available in the literature. Generally, the minimum inhibitory concentrations of antifungal drugs against this species were low. In conclusion, C. africana demonstrates geographical variation in prevalence and high susceptibility to antifungal drugs. However, due to the relative scarcity of existing data concerning this species, further studies will be required to establish more firm conclusions.

A Prognostic Nomogram Combining Immune-Related Gene Signature and Clinical Factors Predicts Survival in Patients With Lung Adenocarcinoma.

The existence of tumor heterogeneity and complex carcinogenic mechanisms in lung adenocarcinoma (LUAD) make the most commonly used TNM staging system unable to well-interpret the prognosis of patients. Using transcriptome profiling and clinical data from The Cancer Genome Atlas (TCGA) database, we constructed an immune signature based on a multivariate Cox analysis (stepwise model). We estimated the half-maximal inhibitory concentration (IC50) of chemotherapeutic drugs in patients according to the pRRophetic algorithm. Gene-set variation analysis (GSVA) was used to reveal pathway enrichment between groups. Moreover, immune microenvironment landscape was described by single-sample gene-set enrichment analysis (ssGSEA) and CIBERSORT and systematically correlated with genomic of these patients. A prognostic nomogram combining the immune signature and TNM stage to predict the prognosis was developed by multivariate Cox regression. The novel signature with four immune-related genes (MAL, MS4A1, OAS1, and WFDC2) had good robustness, which can accurately distinguish between high- and low-risk patients. Compared with low-risk patients, high-risk patients with a worse prognosis (5-year OS: 46.5 vs. 59.4%, p = 0.002) could benefit more from immunotherapy and the application of common chemotherapeutic agents such as cisplatin and paclitaxel (Wilcoxon test, all p < 0.05). There were significant differences in tumor immune microenvironment and metabolic pathways between the two groups. Additionally, the constructed nomogram had reliable predictive performance with the C-index of 0.725 (95% CI = 0.668–0.781) in the development set (n = 500), 0.793 (95% CI = 0.728–0.858) in the internal validation set (n = 250) and 0.679 (95% CI = 0.644–0.714) in the external validation set (n = 442). The corresponding calibration curves also showed good consistency. To sum up, we developed an immune-related gene signature and comprehensively evaluated LUAD immune landscape and metabolic pathways. Effective differentiation of high- and low-risk patients and accurate construction of nomogram would be helpful to the development of individualized treatment strategies.

In Vitro Antifungal Activity of Green Synthesized Silver Nanoparticles in Comparison to Conventional Antifungal Drugs Against Trichophyton Interdigitale, Trichophyton Rubrum and Epidermophyton Floccosum.

Dermatophytosis is a globally distributed fungal infection. Treatment failure and relapse is common in this disease. Silver nanoparticles are known for their promising antimicrobial activity. The aim of this study was to determine the antifungal activity of these nanoparticles against common dermatophyte species. A set of 30 molecularly identified dermatophytes including Trichophyton interdigitale (n=10), Trichophyton rubrum (n=10), and Epidermophyton floccosum (n=10) were used in this study. Green synthesized silver nanoparticles using chicory (Cichorium intybus) were tested for their antifungal activity in comparison to fluconazole, itraconazole and terbinafine. Interspecies differences in minimum inhibitory concentrations of antifungal drugs and silver nanoparticles were tested using Kruskal-Wallis test in SPSS software version 21. The highest minimum inhibitory concentrations (MICs) among antifungal drugs were observed for fluconazole [range: 4-64 μg/mL, geometric mean (GM) =17.959 μg/mL], followed by itraconazole (range: 0.008-0.5, GM= 0.066) and terbinafine (range: 0.004-0.25 μg/mL, GM=0.027 μg/mL). Silver nanoparticles showed potent antifungal activity against all dermatophyte isolates with MICs (range: 0.25-32 μg/mL, GM=4.812 μg/mL) higher than those of itraconazole and terbinafine, but lower than fluconazole. MIC values of silver nanoparticles demonstrated significant differences between species (P=0.044), with E. floccosum having the highest MICs (GM=9.849 μg/mL) compared to T. interdigitale (GM=3.732 μg/mL) and T. rubrum (GM=3.031 μg/mL). Silver nanoparticles demonstrated promising anti-dermatophyte activity against the studied dermatophytes. Due to their wide-spectrum activity against other fungal and bacterial pathogens, they could be a potential choice, at least in the case of cutaneous and superficial infections.

Wild-Type MIC Distribution for Re-evaluating the Critical Concentration of Anti-TB Drugs and Pharmacodynamics Among Tuberculosis Patients From South India.

The World Health Organization (WHO) has developed specific guidelines for critical concentrations (CCs) of antibiotics used for tuberculosis (TB) treatment, which is universally followed for drug susceptibility testing (DST) of clinical specimens. However, the CC of drugs can differ significantly among the mycobacterial species based on the population, geographic location, and the prevalence of the infecting strain in a particular area. The association between CC and the minimal inhibitory concentration (MIC) of anti-TB drugs is poorly understood. In this study, we assessed the MICs of anti-TB drugs, including isoniazid (INH), rifampicin (RMP), moxifloxacin (MXF), ethambutol (ETH), and p-aminosalicylic acid (PAS) on drug-sensitive Mtb isolates from pulmonary TB patients in South India. The MIC assays performed using solid- and liquid-growth media showed changes in the CC of a few of the tested antibiotics compared with the WHO-recommended levels. Our observation suggests that the WHO guidelines could potentially lead to overdiagnosis of drug-resistant cases, which can result in inappropriate therapeutic decisions. To evaluate the correlation between drug-resistance and CC, we performed the whole-genome sequencing for 16 mycobacterial isolates, including two wild-type and 14 resistant isolates. Our results showed that two of the isolates belonged to the W-Beijing lineage, while the rest were of the East-African–Indian type. We identified a total of 74 mutations, including five novel mutations, which are known to be associated with resistance to anti-TB drugs in these isolates. In our previous study, we determined the serum levels of INH and RMP among the same patients recruited in the current study and estimated the MICs of the corresponding infected isolates in these cases. Using these data and the CCs for INH and RMP from the present study, we performed pharmacodynamics (PD) evaluation. The results show that the PD of RMP was subtherapeutic. Together, these observations emphasize the need for optimizing the drug dosage based on the PD of large-scale studies conducted in different geographical settings.

Architecture based selectivity of Amphiphilic block copolymers of poly(ethylene oxide) and poly(ε-caprolactone) for drug delivery

Architecture of amphiphilic block copolymers is an important parameter that affects their critical micelles concentration (CMC), drug loading capacity and drug release behavior. In this context, 4-arm star-shaped block copolymers comprising of poly(ethylene oxide) as a hydrophilic segment and poly(ε-caprolactone) as a hydrophobic part, 4 s-P(CL-b-EO), is compared with its linear counterpart having otherwise similar total molar mass, chemical composition and molar mass of individual components (PCL-b-PEO-b-PCL). As a first step, the micelles prepared by linear block copolymer (LPM) and star-shaped block copolymer (SPM) were compared for CMC, drug encapsulation capacity, and drug release behavior. Micelles based on star-shaped polymers were found to have low CMC, high drug encapsulation capacity and better sustained release behavior. Blood hemolysis and cytotoxicity studies of both linear and star-shaped block copolymers revealed that these are safer to use for biological applications. Micelles based on star shaped polymers (SPM) and linear block copolymer (LPM) were further employed for individual delivery of cefixime (CEF) and its co-delivery with clarithromycin (CLA). Finally, growth inhibition efficiency of SPM, LPM, CEF, CLA, CEF-SPM, CEF-LPM, CEF-CLA-SPM, and CEF-CLA-LPM are evaluated against S. pneumoniae and S. pneumoniae (resistant) by antibacterial assay and morphological topography imaging by AFM. Minimum inhibitory concentration (MIC50) of drugs encapsulated in SPM is found to be considerably lower compared to direct application of drugs and drug encapsulated in LPM.