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BACKGROUND: Due to a delay in diagnosis by conventional techniques and high mortality, the development of a standardised and rapid non-culture-based technique is an unmet need in pulmonary, gastrointestinal, and disseminated forms of mucormycosis. Though limited studies have been conducted for molecular diagnosis, there are no established serologic tests for this highly fatal infection. OBJECTIVE: To develop and evaluate an indirect in-house enzyme-linked immunosorbent assay (ELISA) utilising antigens of Rhizopus arrhizus for detecting anti-Rhizopus antibodies (IgG and IgM) in sera of patients with mucormycosis. METHODS: We extracted both secretory and mycelial Rhizopus antigens using standardised protocols. Bradford assay was used for protein quantification. We then standardised an indirect ELISA using R. arrhizus mycelial and secretory antigens (10.0 µg/mL in bicarbonate buffer pH 9.2) for detecting anti-Rhizopus IgG and IgM antibodies in patient sera. We included patients with mucormycosis, other fungal infections, and healthy controls. Antibody index value (E-value) was calculated for each patient sample. RESULTS: Asparagine broth culture filtrate utilising 85% ammonium sulphate salt fractionation and mycelial homogenate grown in yeast extract peptone dextrose (YPD) broth precipitated with trichloroacetic acid (TCA) yielded a large amount of good-quality protein for the assay. We included 55 patients with mucormycosis (rhino-orbito-cerebral mucormycosis [ROCM, n = 39], pulmonary [n = 15], gastrointestinal [n = 1]), 24 with other fungal infections (probable aspergillosis [n = 14], candidiasis [n = 10]), and healthy controls (n = 16). The sensitivity of the antibody test for diagnosing mucormycosis ranged from 83.6-92.7% for IgG and 72.7-87.3% for IgM, with a specificity of 91.7-92.5% for IgG and 80-82.5% for IgM. The sera from patients with other fungal infections and healthy individuals did not show significant cross-reactivity. CONCLUSION: The detection of anti-Rhizopus IgG antibody performed significantly better in comparison to IgM-based ELISA for diagnosing both ROCM (sensitivity of 84.6% vs. 69.2%) and pulmonary cases (86.6% vs. 80.0%). More extensive studies are required to confirm our findings.
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Anticuerpos Antifúngicos , Antígenos Fúngicos , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G , Inmunoglobulina M , Mucormicosis , Rhizopus , Sensibilidad y Especificidad , Pruebas Serológicas , Mucormicosis/diagnóstico , Mucormicosis/microbiología , Mucormicosis/inmunología , Humanos , Rhizopus/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Antígenos Fúngicos/inmunología , Antígenos Fúngicos/análisis , Pruebas Serológicas/métodos , Anticuerpos Antifúngicos/sangre , Inmunoglobulina M/sangre , Inmunoglobulina G/sangre , Femenino , Masculino , Persona de Mediana EdadRESUMEN
2-Methyl-2-butene has recently been reported to be a quorum-based volatile self-inhibitor of spore germination and growth in pathogenic Mucorale Rhizopus arrhizus. The present study aimed to elucidate if this compound can influence R. arrhizus biofilm formation and interspecies interaction. The compound was found to significantly decrease R. arrhizus biofilm formation (p < 0.001), with nearly 25% and 50% lesser biomass in the biofilms cultured with exposure to 4 and 32 µg/ml of 2-methyl-2-butene, respectively. The growth of pre-formed biofilms was also impacted, albeit to a lesser extent. Additionally, 2-methyl-2-butene was found to self-limit R. arrhizus growth during interspecies interaction with Staphylococcus aureus and was detected at a substantially greater concentration in the headspace of co-cultures (2338.75 µg/ml) compared with monocultures (69.52 µg/ml). Some of the C5 derivatives of this compound (3-methyl-1-butanol, 2-methyl-2-butanol, and 3-methyl-1-butyne) were also observed to partially mimic its action, such as inhibition of spore germination, but did not impact R. arrhizus biofilm formation. Finally, the treated R. arrhizus displayed changes in fungal morphology suggestive of cytoskeletal alterations, such as filopodia formation, blebs, increased longitudinal folds and/or corrugations, and finger-like and sheet-like surface protrusions, depending upon the concentration of the compound(s) and the planktonic or biofilm growth mode.
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Rhizopus oryzae , Rhizopus , Alquenos , Biopelículas , Staphylococcus aureusRESUMEN
Rett syndrome (RTT) is a rare disorder and one of the most abundant causes of intellectual disabilities in females. Single mutations in the gene coding for methyl-CpG-binding protein 2 (MeCP2) are responsible for the disorder. MeCP2 regulates gene expression as a transcriptional regulator as well as through epigenetic imprinting and chromatin condensation. Consequently, numerous biological pathways on multiple levels are influenced. However, the exact molecular pathways from genotype to phenotype are currently not fully elucidated. Treatment of RTT is purely symptomatic as no curative options for RTT have yet to reach the clinic. The paucity of this is mainly due to an incomplete understanding of the underlying pathophysiology of the disorder with no clinically useful common disease drivers, biomarkers, or therapeutic targets being identified. With the premise of identifying universal and robust disease drivers and therapeutic targets, here, we interrogated a range of RTT transcriptomic studies spanning different species, models, and MECP2 mutations. A meta-analysis using RNA sequencing data from brains of RTT mouse models, human post-mortem brain tissue, and patient-derived induced pluripotent stem cell (iPSC) neurons was performed using weighted gene correlation network analysis (WGCNA). This study identified a module of genes common to all datasets with the following ten hub genes driving the expression: ATRX, ADCY7, ADCY9, SOD1, CACNA1A, PLCG1, CCT5, RPS9, BDNF, and MECP2. Here, we discuss the potential benefits of these genes as therapeutic targets.
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Síndrome de Rett , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Cromatina , Femenino , Humanos , Proteína 2 de Unión a Metil-CpG/metabolismo , Ratones , Mutación , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Superóxido Dismutasa-1/genéticaRESUMEN
Tobacco control methods differ by country, with telephonic counseling being one of them. The effectiveness of telephone counseling in smoking cessation has been discussed on several occasions. India's tobacco problem is more complex than that of any other country in the world. To begin with, tobacco is consumed in a variety of ways, and India is a large multilingual country with remarkable cultural diversity. In India, the National Tobacco Quitline Service (NTQLS) is a government-run program. Its data from May 2016 to May 2021 were analyzed retrospectively in this cross-sectional study to determine the prevalence and pattern of tobacco use in India, as well as the abstinence rate for smoking cessation. A total of 4,611,866 calls were received by the Interactive Voice Response system (IVR). The number of calls increased from 600 to 5400 per day after the toll-free number was printed on all tobacco products. Smokeless tobacco use was discovered to be more prevalent, with males significantly more likely to use both smoking and smokeless tobacco. At one month and one year after quitting, 33.42% and 21.9%, respectively, remained tobacco-free. The study emphasizes the efficacy of behavioral counseling in increasing abstinence rates. The printing of a toll-free number on tobacco products is an effective strategy for expanding the operation of quit lines. Despite the challenges of cultural diversity and complex tobacco use, India's quit line service has been able to provide counseling to callers with prolonged abstinence and quit rates comparable to the various quit lines around the world.
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Cese del Hábito de Fumar , Masculino , Humanos , Cese del Hábito de Fumar/métodos , Estudios Transversales , Estudios Retrospectivos , Consejo/métodos , Fumar/epidemiologíaRESUMEN
PURPOSE: To develop and validate a one-step, rapid and simple reversed-phase high-performance liquid chromatography (HPLC)-based protocol for the simultaneous measurement of voriconazole (VCZ), posaconazole (POSA), itraconazole (ITC) in serum/plasma. METHODS: Calibration standards (CS) and quality control samples were prepared in drug-free serum by spiking with the triazoles at different concentrations. HPLC was performed with C18 column, isocratic mobile phase after extraction with cold acetonitrile. The standardized method was tested in 2693 patients' serum/plasma samples. RESULTS: Linearity of CS for ITC, VCZ and POSA was proportional to the nominal concentration (correlation coefficient > 0.999). Limit of detection (mg/L) for ITC, VCZ and POSA was 0.25, 0.25 and 0.125, respectively. The lower limit of quantification (mg/L) for ITC, VCZ and POSA was 0.5, 0.5 and 0.25, respectively. Precision and accuracy were in acceptable range with 100% average percentage recovery. No interferences from endogenous substances and other antimicrobial compounds were noted. In clinical samples, the therapeutic range achieved for VCZ was 39.9%. Whereas, 61.1% and 44% of samples with ITC and POSA, respectively, were in the sub-therapeutic range. CONCLUSION: We developed a rapid and simple HPLC method to quantify common triazoles in a single chromatographic run allowing simultaneous measurement of different antifungals in a small volume of serum/plasma. Thus, therapeutic drug monitoring requests can be processed in one run without changing the protocol parameters, column or column conditioning thereby improving turnaround time.
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Antifúngicos , Triazoles , Cromatografía Líquida de Alta Presión , Humanos , Itraconazol , Reproducibilidad de los Resultados , VoriconazolRESUMEN
Resveratrol is a polyphenolic nutraceutical that exhibits pleiotropic activities in human subjects. The efficacy, safety, and pharmacokinetics of resveratrol have been documented in over 244 clinical trials, with an additional 27 clinical trials currently ongoing. Resveretrol is reported to potentially improve the therapeutic outcome in patients suffering from diabetes mellitus, obesity, colorectal cancer, breast cancer, multiple myeloma, metabolic syndrome, hypertension, Alzheimer's disease, stroke, cardiovascular diseases, kidney diseases, inflammatory diseases, and rhinopharyngitis. The polyphenol is reported to be safe at doses up to 5 g/d, when used either alone or as a combination therapy. The molecular basis for the pleiotropic activities of resveratrol are based on its ability to modulate multiple cell signaling molecules such as cytokines, caspases, matrix metalloproteinases, Wnt, nuclear factor-κB, Notch, 5'-AMP-activated protein kinase, intercellular adhesion molecule, vascular cell adhesion molecule, sirtuin type 1, peroxisome proliferator-activated receptor-γ coactivator 1α, insulin-like growth factor 1, insulin-like growth factor-binding protein 3, Ras association domain family 1α, pAkt, vascular endothelial growth factor, cyclooxygenase 2, nuclear factor erythroid 2 like 2, and Kelch-like ECH-associated protein 1. Although the clinical utility of resveratrol is well documented, the rapid metabolism and poor bioavailability have limited its therapeutic use. In this regard, the recently produced micronized resveratrol formulation called SRT501, shows promise. This review discusses the currently available clinical data on resveratrol in the prevention, management, and treatment of various diseases and disorders. Based on the current evidence, the potential utility of this molecule in the clinic is discussed.
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Antioxidantes/uso terapéutico , Resveratrol/uso terapéutico , Animales , Diabetes Mellitus/tratamiento farmacológico , Humanos , Síndrome Metabólico/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Obesidad/tratamiento farmacológicoRESUMEN
BACKGROUND: Candida auris, an emerging nosocomial pathogen, exhibits phenotypic variation. Non-aggregating C. auris isolates display greater biofilm-forming capacity and virulence than aggregate-forming isolates. Most of the studies till date have focused on clinical isolates. The biofilm-forming capacity of colonising isolates remains uninvestigated. OBJECTIVES: The present study aimed to elucidate the biofilm-forming capacity of the colonising isolates of C. auris, correlate it with their aggregation behaviour and antifungal susceptibility, and compare it with that of the isolates from blood-stream infection. METHODS: Colonising and clinical (candidemia) isolates of C. auris were screened for aggregation behaviour, biofilm-forming capacity and antifungal susceptibility testing. Aggregation behaviour was assessed microscopically. Biofilm-forming capacity was determined on 96-well flat-bottomed microtitre plates. Antifungal susceptibility testing was performed by broth microdilution assay. RESULTS: Aggregative and non-aggregative phenotypes were found to be predominantly associated with colonising and clinical isolates, respectively, with the former ones being stronger biofilm producers in the colonising group. Non-aggregative isolates in the colonising group showed lower susceptibility to amphotericin B and fluconazole than aggregative isolates. In contrast, no association was noted between biofilm formation, aggregation behaviour and antifungal susceptibility amongst the clinical isolates. CONCLUSION: Biofilm formation is a strain-dependent trait in C. auris, strongly associated with the type and phenotypic behaviour of the isolates. Colonising isolates of this fungus were found to be predominantly aggregative in nature, with a higher biofilm-forming capacity than non-aggregative ones.
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Antifúngicos/farmacología , Biopelículas/crecimiento & desarrollo , Candida/fisiología , Candidemia/microbiología , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Candida/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana , VirulenciaRESUMEN
BACKGROUND: Endophytes have proven to be an invaluable resource of chemically diverse secondary metabolites that act as excellent lead compounds for anticancer drug discovery. Here we report the promising cytotoxic effects of Cladosporol A (HPLC purified >98%) isolated from endophytic fungus Cladosporium cladosporioides collected from Datura innoxia. Cladosporol A was subjected to in vitro cytotoxicity assay against NCI60 panel of human cancer cells using MTT assay. We further investigated the molecular mechanism(s) of Cladosporol A induced cell death in human breast (MCF-7) cancer cells. Mechanistically early events of cell death were studied using DAPI, Annexin V-FITC staining assay. Furthermore, immunofluorescence studies were carried to see the involvement of intrinsic pathway leading to mitochondrial dysfunction, cytochrome c release, Bax/Bcl-2 regulation and flowcytometrically measured membrane potential loss of mitochondria in human breast (MCF-7) cancer cells after Cladosporol A treatment. The interplay between apoptosis and autophagy was studied by microtubule dynamics, expression of pro-apoptotic protein p21 and autophagic markers monodansylcadaverine staining and LC3b expression. RESULTS: Among NCI60 human cancer cell line panel Cladosporol A showed least IC50 value against human breast (MCF-7) cancer cells. The early events of apoptosis were characterized by phosphatidylserine exposure. It disrupts microtubule dynamics and also induces expression of pro-apoptotic protein p21. Moreover treatment of Cladosporol A significantly induced MMP loss, release of cytochrome c, Bcl-2 down regulation, Bax upregulation as well as increased monodansylcadaverine (MDC) staining and leads to LC3-I to LC3-II conversion. CONCLUSION: Our experimental data suggests that Cladosporol A depolymerize microtubules, sensitize programmed cell death via ROS mediated autophagic flux leading to mitophagic cell death. The proposed mechanism of Cladosporol A -triggered apoptotic as well as autophagic death of human breast cancer (MCF-7) cells. The figure shows that Cladosporol A induced apoptosis through ROS mediated mitochondrial pathway and increased p21 protein expression in MCF-7 cells in vitro.
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Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/fisiopatología , Naftoles/farmacología , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/antagonistas & inhibidores , Apoptosis/fisiología , Autofagia/fisiología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromosomas/efectos de los fármacos , Cromosomas/metabolismo , Cladosporium/clasificación , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Citocromos c/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/fisiología , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Especies Reactivas de Oxígeno/antagonistas & inhibidoresRESUMEN
Stationary-phase bacteria are important in disease. The σ(s)-regulated general stress response helps them become resistant to disinfectants, but the role of σ(s) in bacterial antibiotic resistance has not been elucidated. Loss of σ(s) rendered stationary-phase Escherichia coli more sensitive to the bactericidal antibiotic gentamicin (Gm), and proteomic analysis suggested involvement of a weakened antioxidant defense. Use of the psfiA genetic reporter, 3'-(p-hydroxyphenyl) fluorescein (HPF) dye, and Amplex Red showed that Gm generated more reactive oxygen species (ROS) in the mutant. HPF measurements can be distorted by cell elongation, but Gm did not affect stationary-phase cell dimensions. Coadministration of the antioxidant N-acetyl cysteine (NAC) decreased drug lethality particularly in the mutant, as did Gm treatment under anaerobic conditions that prevent ROS formation. Greater oxidative stress, due to insufficient quenching of endogenous ROS and/or respiration-linked electron leakage, therefore contributed to the greater sensitivity of the mutant; infection by a uropathogenic strain in mice showed this to be the case also in vivo. Disruption of antioxidant defense by eliminating the quencher proteins, SodA/SodB and KatE/SodA, or the pentose phosphate pathway proteins, Zwf/Gnd and TalA, which provide NADPH for ROS decomposition, also generated greater oxidative stress and killing by Gm. Thus, besides its established mode of action, Gm also kills stationary-phase bacteria by generating oxidative stress, and targeting the antioxidant defense of E. coli can enhance its efficacy. Relevant aspects of the current controversy on the role of ROS in killing by bactericidal drugs of exponential-phase bacteria, which represent a different physiological state, are discussed.
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Antibacterianos/farmacología , Antioxidantes/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Gentamicinas/farmacología , Factor sigma/metabolismo , Animales , Femenino , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , RatonesRESUMEN
Mucormycosis remains a devastating invasive fungal infection, with high mortality rates even after active management. The disease is being reported at an alarming frequency over the past decades from India. Indian mucormycosis has certain unique features. Rhino-orbito-cerebral presentation associated with uncontrolled diabetes is the predominant characteristic. Isolated renal mucormycosis has emerged as a new clinical entity. Apophysomyces elegans and Rhizopus homothallicus are emerging species in this region and uncommon agents such as Mucor irregularis and Thamnostylum lucknowense are also being reported. This review focuses on these distinct features of mucormycosis observed in India.
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Complicaciones de la Diabetes/microbiología , Mucormicosis/epidemiología , Diabetes Mellitus/patología , Humanos , Incidencia , India/epidemiología , Mucorales/patogenicidad , Mucormicosis/microbiología , Rhizopus/patogenicidad , Factores de RiesgoRESUMEN
Background Nerve conduction studies ease the understanding of the various pathologies of the peripheral nervous system. It helps physicians to delineate between the two principal types of peripheral etiologies: axonal degeneration and demyelination. An increase in weight in the form of excessive fat deposition or obesity could have a worrisome effect on nerve conduction. So, to find the association of various anthropometric parameters (age, gender, height, weight, waist-hip ratio and body mass index) with motor and sensory median nerve conduction parameters (latency, amplitude and velocity) this cross-sectional study was conducted. Materials and method A total of 87 subjects were taken and their height, weight, waist-hip ratio and body mass index were measured using standard techniques. Motor and sensory nerve conduction parameters were measured on an electromyography machine. Data was stored, tabulated and analyzed. Results The average height of male and female subjects ± SD was 1.699 ± 0.072 m and 1.589 ± 0.067 m respectively. The average weight of male and female subjects ± SD was 64.089 ± 11.497 kg and 52.949 ± 8.404 kg, respectively. The average BMI of normal, underweight and overweight subjects ± SD was 21.668 ± 2.048 kg/m2, 17.074 ± 0.794 kg/m2 and 26.595 ± 0.915 kg/m2 respectively. Weight showed a significant (p = 0.0025) correlation with the latency of motor median nerve conduction. Waist-hip ratio showed a significant (p = 0.042 and p = 0.036) correlation with motor median nerve conduction velocity in both male and female subjects, respectively. BMI in the overweight category showed a significant (p = 0.0156 and p = 0.0290) correlation with latency and amplitude of motor median nerve conduction study, respectively. Conclusions This study exemplifies that an increase in BMI of our body can affect nerve conduction. This could serve as a preliminary study to assess the effect of obesity on peripheral nerve conduction, especially in the Indian population.
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Fungisome(TM) is a liposomal preparation of amphotericin B (AMB), already marketed in India. However, its antifungal activity has not been evaluated against a wide range of fungal pathogens. The study was planned to elucidate the in vitro antifungal activity of Fungisome(TM) against wide range of fungi and compare it with AMB deoxycholate (AMB-d), voriconazole (VOR), itraconazole (ITR) and fluconazole (FLU). Minimum inhibitory concentrations (MICs) of the drugs were determined for 262 clinical fungal isolates, including yeast, dimorphic and filamentous fungi, by broth microdilution method approved by Clinical and Laboratory Standards Institute, USA (yeast, M27-A3; filamentous fungi, M38-A2). The MIC(90s) of Fungisome(TM) were 0.125, 0.5 and 0.25 mg l(-1) against yeast, filamentous and dimorphic fungi respectively. In comparison, MIC(90s) of AMB-d, FLU, ITR and VOR were 1, 1 and 1 mg l(-1) (AMB-d), 4, 64 and 64 mg l(-1) (FLU), 1, 16 and 16 mg l(-1) (ITR) and 0.5, 4 and 16 mg l(-1) (VOR) against yeast, filamentous and dimorphic fungi respectively. The MIC of Fungisome(TM) was two to 16-fold lower than AMB-d. These results reveal an efficient in vitro activity of Fungisome(TM).
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Antifúngicos/farmacología , Hongos/efectos de los fármacos , Levaduras/efectos de los fármacos , Anfotericina B/farmacología , Ácido Desoxicólico/farmacología , Combinación de Medicamentos , Fluconazol/farmacología , Humanos , Itraconazol/farmacología , Pruebas de Sensibilidad Microbiana , Pirimidinas/farmacología , Triazoles/farmacología , VoriconazolRESUMEN
Investigations on atmospheric deposition (AD) and water chemistry along a 35 km stretch of Ganga River indicated that although N:P stoichiometry of AD did not change, there were over 1.4-2.0 fold increase in AD-NO3â», AD-NH4⺠and AD-PO4³â» overtime. Concentration of dissolved inorganic-N (DIN) in river showed significant positive correlations with AD-NO3â» and runoff DIN. Similarly, dissolved reactive-P (DRP) in river showed significant positive correlation with AD-PO4³â» and runoff DRP. The study shows that AD has become an important source of N and P input to Ganga River.
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Nitrógeno/análisis , Fósforo/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , IndiaRESUMEN
Klebsiella pneumoniae is an opportunistic pathogen associated with biofilm-based infections, which are intrinsically antibiotic resistant. Extracellular DNA plays a crucial role in biofilm formation and self-defence, with nucleases being proposed as promising agents for biofilm disruption. This study evaluated the in vitro and in vivo efficacy of DNase I in improving the activity of cefotaxime, amikacin, and ciprofloxacin against K. pneumoniae biofilms. K. pneumoniae ATCC 700603 and a clinical isolate from catheter-related bloodstream infection were cultured for biofilm formation on microtiter plates, and the antibiofilm activity of the antibiotics (0.03-64 mg/L), with or without bovine pancreatic DNase I (1-32 mg/L) was determined by XTT dye reduction test and viable counting. The effect of ciprofloxacin (2 mg/L) and DNase I (16 mg/L) was further evaluated in vitro on 1-cm-long silicon catheter segments, and in a mouse model of subcutaneous catheter-associated infection. Combination with DNase I did not improve the biofilm-preventive capacity of the three antibiotics or the biofilm-eradicating capacity of cefotaxime and amikacin. The biofilm-eradicating capacity of ciprofloxacin was increased by 8-fold and 4-fold in K. pneumoniae ATCC 700603 and clinical isolate, respectively, with DNase I. The combination therapy caused 99% reduction in biofilm biomass in the mouse model.
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Antibacterianos , Klebsiella pneumoniae , Ratones , Animales , Bovinos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Amicacina/farmacología , Desoxirribonucleasa I/farmacología , Pruebas de Sensibilidad Microbiana , Ciprofloxacina/farmacología , Biopelículas , Modelos Animales de Enfermedad , Cefotaxima/farmacologíaRESUMEN
Most studies on fungal biofilms have focused on Candida in yeasts and Aspergillus in mycelial fungi. To the authors' knowledge, biofilm formation by zygomycetes has not been reported previously. In this study, the biofilm-forming capacity of Rhizopus oryzae, Lichtheimia corymbifera, Rhizomucor pusillus and Apophysomyces elegans was evaluated. At appropriate seeding spore densities, Rhp. oryzae (105 c.f.u. ml⻹, L. corymbifera (104 c.f.u. ml⻹) and Rhm. pusillus (104 c.f.u. ml⻹) produced highly intertwined, adherent structures on flat-bottomed polystyrene microtitre plates after 24 h at 37 °C. The adhered fungal hyphae were encased in an extracellular matrix, as confirmed by phase-contrast and confocal microscopy. The thickness of Rhp. oryzae, L. corymbifera and Rhm. pusillus biofilms was 109.67±10.02, 242±23.07 and 197±9.0 µm (mean±sd), respectively. Biochemical characterization of the biofilm matrix indicated the presence of glucosamine, constituting 74.54-82.22â% of its dry weight, N-acetylglucosamine, glucose and proteins. Adherence and biofilm formation were not observed in A. elegans. Although A. elegans spores germinated at all three seeding densities tested (1×107, 1×106 and 1×105 c.f.u. ml⻹), no significant difference was observed (P>0.05) between the A490 of wells inoculated with A. elegans and the cut-off A490 for biofilm detection. This study highlights the potential for biofilm formation by at least three medically important species of zygomycetes.
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Biopelículas/crecimiento & desarrollo , Mucorales/fisiología , Adhesión Celular , Hifa , Cinética , Microscopía ConfocalRESUMEN
PURPOSE OF REVIEW: The present review describes the emerging trends of mould infections in developing countries, and highlights the major epidemiological differences from the developed countries. RECENT FINDINGS: The limited data available from developing countries suggest an alarming increase in invasive mould infections, especially aspergillosis and mucormycosis, and also a difference in risk factors and causative agents between the developed and developing world. Sino-orbital, cerebral and ophthalmic infections due to Aspergillus flavus are the major clinical types in aspergillosis, after pulmonary aspergillosis. Aspergillus and Fusarium spp. are frequent causes of trauma-associated keratitis in agricultural workers. Rhino-orbito-cerebral presentation associated with uncontrolled diabetes is the predominant mucormycosis. Isolated renal mucormycosis has emerged as a new clinical entity. Apophysomyces elegans and Mucor irregularis are emerging species in these regions and uncommon agents such as Rhizopus homothallicus have also been reported. Many pathogens are geographically restricted, with Pythium insidionum, Rhinocladiella mackenziei and M. irregularis being described almost exclusively from Thailand, Middle East and China, respectively. SUMMARY: Despite limited studies, certain peculiarities have been observed in invasive mould infections in developing countries, including a high incidence of ophthalmic lesions, mucormycosis and aspergillosis; few different clinical presentations; and a varied spectrum of pathogens involved in such lesions.
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Países en Desarrollo/estadística & datos numéricos , Micosis/epidemiología , Aspergilosis/epidemiología , Humanos , Mucormicosis/epidemiología , Micosis/microbiología , Prevalencia , Factores de Riesgo , Cigomicosis/epidemiologíaRESUMEN
COVID-19 associated mucormycosis (CAM) is being reported at an elevated frequency and has been declared an ongoing epidemic in India. A huge diabetic population, inappropriate corticosteroid usage and environmental mucoralean spore count, along with COVID-19 associated glycemic imbalance, hypoxemia, increased iron levels, vascular endothelial injury, as well as the immunosuppressive impact are being considered as important risk factors for CAM. The present viewpoint aims to discuss the plausible role of another important facet, the nasal microbiota imbalance, in the emergence of mucormycosis under the prevailing COVID-19 pandemic conditions.