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1.
BMC Plant Biol ; 24(1): 806, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39187756

RESUMEN

BACKGROUND: Scopoletin and umbelliferone belong to coumarins, which are plant specialized metabolites with potent and wide biological activities, the accumulation of which is induced by various environmental stresses. Coumarins have been detected in various plant species, including medicinal plants and the model organism Arabidopsis thaliana. In recent years, key role of coumarins in maintaining iron (Fe) homeostasis in plants has been demonstrated, as well as their significant impact on the rhizosphere microbiome through exudates secreted into the soil environment. Several mechanisms underlying these processes require clarification. Previously, we demonstrated that Arabidopsis is an excellent model for studying genetic variation and molecular basis of coumarin accumulation in plants. RESULTS: Here, through targeted metabolic profiling and gene expression analysis, the gene-metabolite network of scopoletin and umbelliferone accumulation was examined in more detail in selected Arabidopsis accessions (Col-0, Est-1, Tsu-1) undergoing different culture conditions and characterized by variation in coumarin content. The highest accumulation of coumarins was detected in roots grown in vitro liquid culture. The expression of 10 phenylpropanoid genes (4CL1, 4CL2, 4CL3, CCoAOMT1, C3'H, HCT, F6'H1, F6'H2,CCR1 and CCR2) was assessed by qPCR in three genetic backgrounds, cultured in vitro and in soil, and in two types of tissues (leaves and roots). We not only detected the expected variability in gene expression and coumarin accumulation among Arabidopsis accessions, but also found interesting polymorphisms in the coding sequences of the selected genes through in silico analysis and resequencing. CONCLUSIONS: To the best of our knowledge, this is the first study comparing accumulation of simple coumarins and expression of phenylpropanoid-related genes in Arabidopsis accessions grown in soil and in liquid cultures. The large variations we detected in the content of coumarins and gene expression are genetically determined, but also tissue and culture dependent. It is particularly important considering that growing plants in liquid media is a widely used technology that provides a large amount of root tissue suitable for metabolomics. Research on differential accumulation of coumarins and related gene expression will be useful in future studies aimed at better understanding the physiological role of coumarins in roots and the surrounding environments.


Asunto(s)
Arabidopsis , Escopoletina , Umbeliferonas , Arabidopsis/genética , Arabidopsis/metabolismo , Escopoletina/metabolismo , Umbeliferonas/metabolismo , Glicósidos/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
2.
Fungal Genet Biol ; 164: 103766, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36513262

RESUMEN

Metarhizium rileyiis an entomopathogenic fungus with a narrow host range which distinguishes it from other Metarhiziumspecies with broad host ranges. This species is also unique because the initial yeast-like growth on solid media is only observed in liquid culture in other Metharizium species. A lack of knowledge about the metabolism and genetic signatures of M. rileyiduring this yeast-like phase on solid and in liquid media is a bottleneck for its large-scale production as a commercial biocontrol agent.In this study wefound that M. rileyiyeast-like cells produced on solid medium infected and killed the important insect pest Spodoptera frugiperda with comparable efficiency as yeast-like cells grown in liquid medium. Secondly, we used comparative transcriptomic analysis to investigate theactive genes and genomic signatures of the M. rileyi yeast-like morphotypes produced on solid and in liquid media. Yeast-like cells grown in liquid medium had upregulated genes relating specifically to signal transduction andparticular membrane transporters. Thirdly, we compared the transcriptomic profiles of yeast-like phases of M. rileyi with those of M. anisopliae. The yeast-like phase of M. rileyi grown on solid medium upregulated unique genes not found in otherMetarhiziumspecies including specific membrane proteins and several virulence factors. Orthologous genes associated with heat shock protein, iron permease, membrane proteins and key virulence traits (e.g. collagen-like protein Mcl1) were upregulated in both species. Comparative transcriptome analyses of gene expression showed more differences than similarities between M. anisopliae and M. rileyi yeast-like cells.


Asunto(s)
Hifa , Metarhizium , Animales , Perfilación de la Expresión Génica , Hifa/genética , Proteínas de la Membrana/genética , Transcriptoma/genética , Virulencia/genética
3.
BMC Microbiol ; 23(1): 83, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36991312

RESUMEN

BACKGROUND: Biofilm-associated infections are a global threat to our economy and human health; as such, development of antibiofilm compounds is an urgent need. Our previous study identified eleven environmental isolates of endophyte bacteria, actinomycetes, and two strains of Vibrio cholerae as having strong antibiofilm activity, but only tested crude extracts from liquid culture. Here we grew the same bacteria in solid culture to induce the formation of colony biofilms and the expression of genes that may ultimately produce antibiofilm compounds. This research aimed to compare antibiofilm inhibition and destruction activities between liquid and solid cultures of these eleven environmental isolates against the biofilms of representative pathogenic bacteria. RESULTS: We measured antibiofilm activity using the static antibiofilm assay and crystal violet staining. The majority of our isolates exhibited higher inhibitory antibiofilm activity in liquid media, including all endophyte bacteria, V. cholerae V15a, and actinomycetes strains (CW01, SW03, CW17). However, for V. cholerae strain B32 and two actinomycetes bacteria (TB12 and SW12), the solid crude extracts showed higher inhibitory activity. Regarding destructive antibiofilm activity, many endophyte isolates and V. cholerae strains showed no significant difference between culture methods; the exceptions were endophyte bacteria isolate JerF4 and V. cholerae B32. The liquid extract of isolate JerF4 showed higher destructive activity relative to the corresponding solid culture extract, while for V. cholerae strain B32 the solid extract showed higher activity against some biofilms of pathogenic bacteria. CONCLUSIONS: Culture conditions, namely solid or liquid culture, can influence the activity of culture extracts against biofilms of pathogenic bacteria. We compared the antibiofilm activity and presented the data that majority of isolates showed a higher antibiofilm activity in liquid culture. Interestingly, solid extracts from three isolates (B32, TB12, and SW12) have a better inhibition or/and destruction antibiofilm activity compared to their liquid culture. Further research is needed to characterize the activities of specific metabolites in solid and liquid culture extracts and to determine the mechanisms of their antibiofilm actions.


Asunto(s)
Actinobacteria , Vibrio cholerae , Humanos , Endófitos , Actinomyces , Biopelículas , Bacterias , Antibacterianos/farmacología
4.
Appl Microbiol Biotechnol ; 107(23): 7181-7196, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37733051

RESUMEN

The entomopathogenic nematode (EPN) Heterorhabditis bacteriophora is an effective biological-control agent of insect pests. The dauer juveniles (DJs) seek for, infect insects, and release cells of the carried symbiotic bacterium of the genus Photorhabdus. Inside the host, the DJs perceive signals from the insect's haemolymph that trigger the exit from the arrested stage and the further development to mature adults. This developmental step is called DJ recovery. In commercial production, a high and synchronous DJ recovery determines the success of liquid-culture mass production. To enhance the understanding about genetic components regulating DJ recovery, more than 160 mutant- and 25 wild type inbred lines (WT ILs) were characterized for DJ recovery induced by cell-free bacterial supernatant. The mutant lines exhibited a broader DJ recovery range than WT ILs (4.6-67.2% vs 1.6-35.7%). A subset of mutant lines presented high variability of virulence against mealworm (Tenebrio molitor) (from 22 to 78% mortality) and mean time survival under oxidative stress (70 mM H2O2; from 10 to 151 h). Genotyping by sequencing of 96 mutant lines resulted in more than 150 single nucleotide polymorphisms (SNPs), of which four results are strongly associated with the DJ recovery trait. The present results are the basis for future approaches in improving DJ recovery by breeding under in vitro liquid-culture mass production in H. bacteriophora. This generated platform of EMS-mutants is as well a versatile tool for the investigation of many further traits of interest in EPNs. KEYPOINTS: • Exposure to bacterial supernatants of Photorhabdus laumondii induces the recovery of Heterorhabditis bacteriophora dauer juveniles (DJs). Both, the bacteria and the nematode partner, influence this response. However, the complete identity of its regulators is not known. • We dissected the genetic component of DJ recovery regulation in H. bacteriophora nematodes by generating a large array of EMS mutant lines and characterizing their recovery pheno- and genotypes. • We determined sets of mutants with contrasting DJ recovery and genotyped a subset of the EMS-mutant lines via genotyping by sequencing (GBS) and identified SNPs with significant correlation to the recovery trait.


Asunto(s)
Nematodos , Photorhabdus , Animales , Genotipo , Peróxido de Hidrógeno , Nematodos/genética , Insectos , Photorhabdus/genética , Simbiosis
5.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36688773

RESUMEN

The purpose of this study was to determine the effect of the culture method on the resistance of Salmonella Typhimurium in low water activity foods to storage, plasma, and dry heat. Whole black peppers were used as the model food. S. Typhimurium cultured in liquid broth (tryptic soy broth) or solid agar (tryptic soy agar) and inoculated on whole black pepper was stored or treated with cold plasma or dry heat. Inactivation of S. Typhimurium cultured in liquid medium was higher in all the treatments. Liquid-cultured S. Typhimurium showed higher DPPP = O (diphenyl-1-pyrenylphosphine oxide) values compared to the solid-cultured S. Typhimurium after plasma or dry heat treatment. Furthermore, the unsaturated fatty acid and saturated fatty acid ratio (USFA/SFA) was significantly (P < 0.05) reduced from 0.41 to 0.29 when S. Typhimurium was cultured on solid agar. These results suggested that the use of food-borne pathogens cultured on solid agar is more suitable for low water activity food pasteurization studies.


Asunto(s)
Piper nigrum , Salmonella enterica , Salmonella typhimurium/fisiología , Agar , Calor , Serogrupo , Microbiología de Alimentos , Agua , Recuento de Colonia Microbiana , Salmonella enterica/fisiología
6.
Int J Mol Sci ; 24(3)2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36768683

RESUMEN

The paper focuses on the growth dynamics and biosynthetic characteristics of the microshoot culture of Spiraea betulifolia ssp. aemiliana obtained in vitro in agar-solidified and liquid media. Microshoots cultured in either type of media showed similar growth dynamics. The most active culture growth was observed from day 35 to day 60. A comparative analysis of the contents of flavonoids and phenol carboxylic acids showed a higher level of phenol carboxylic acids (5.3-6.84%) and a stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity (half-maximal inhibitory concentration: 341 µg/mL) in S. betulifolia ssp. aemiliana microshoots grown in the liquid medium compared to the microshoots cultured in the solid medium. The flavonoid content of the cultured microshoot did not depend on the consistency of the medium. High-performance liquid chromatography (HPLC) was employed to study the profile and levels of phenolic compounds in microshoots, intact plants, and ex vitro-acclimated S. betulifolia ssp. aemiliana plants. The concentration of kaempferol glycosides was found to be higher in microshoots (1.33% in the solid medium, 1.06% in the liquid medium) compared to intact plants and ex vitro-acclimated plants. Thus, the microshoots of S. betulifolia ssp. aemiliana cultured in the liquid medium rapidly increase their biomass and are an inexpensive promising source of biologically active antioxidant substances, mainly phenol carboxylic acids and kaempferol glycosides.


Asunto(s)
Quempferoles , Spiraea , Quempferoles/análisis , Flavonoides/farmacología , Antioxidantes/farmacología , Extractos Vegetales/farmacología , Fenoles/análisis , Glicósidos , Ácidos Carboxílicos , Cromatografía Líquida de Alta Presión
7.
Biotechnol Lett ; 44(4): 581-593, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35262812

RESUMEN

Cordycepin (3'-deoxyadenosine) is a nucleoside analogue and biosynthesised by Cordyceps militaris, an entomopathogenic fungus. In this study, an epigenetic modifier was applied to static liquid cultures to enhance cordycepin production. C. militaris was cultured in a static liquid culture, and valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, was supplemented in order to modifying the epigenetic status. Gene regulatory network was explored to understand the molecular mechanisms underlying cordycepin production. 50 micromolar of VPA enhanced cordycepin production by 41.187% via the upregulation of 5'-nucleotidase, adenylate kinase, phosphorybosyltransferase, Cns1, Cns2, Cnsa3, and Cns4 of C. militaris for at least 2 days after VPA treatment. The maximum production of cordycepin was 2,835.32 ± 34.35 mg/L in 400 mL-working volume. A scaled-up culture was established with a working volume of 10 L, which led to the slight decrease of cordycepin production. This might due to multifactorial effects, for instance limited aeration and an uneven dispersion of nutrients in the culture system. This scaled-up culture was still needed further optimization. The modification of epigenetic status by VPA significantly enhanced cordycepin production by altering key gene regulatory network of C. militaris. The strategy established in this study might be applicable to other microorganism culture in order to improving the production of bioactive compounds. This work aimed to enhance the production of cordycepin by modifying the epigenetic status of C. militaris, in which subsequently altered gene regulatory network of cordycepin biosynthesis pathway. The weekly supplementation of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, significantly improve cordycepin production over 40%, compared to the untreated control, and the gene regulatory network of C. militaris was also adapted.


Asunto(s)
Cordyceps , Cordyceps/genética , Cordyceps/metabolismo , Desoxiadenosinas , Epigénesis Genética , Histona Desacetilasas/metabolismo , Ácido Valproico/metabolismo , Ácido Valproico/farmacología
8.
J Invertebr Pathol ; 193: 107800, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35870517

RESUMEN

Increasing the infective juvenile (IJ) yields of entomopathogenic nematodes in monoxenic culture systems would reduce their production cost for the market. Ascarosides act as universal nematode pheromones with developmental and behavioral effects of nematodes. Dimethyl sulfoxide (DMSO) is unexpectedly found to enhance the IJ yields of entomopathogenic nematodes on fortified nutrient broth plates. In this study, the influence of selected ascarosides (ascr#7, ascr#9 and ascr#11) and DMSO in three concentrations on the IJ yields of S. carpocapsae All and H. bacteriophora H06 in liquid culture flasks was determined, and the critical development parameters (IJ recovery rate, number of hermaphrodites, number of visible eggs in a hermaphrodite) were examined for H. bacteriophora H06. The results demonstrated that IJ yields were significantly improved in the liquid medium containing 0.01 % DMSO, and 0.02 nM ascr#11 for S. carpocapsae All, and 0.1 % and 0.01 % DMSO and 0.02 pM ascr#11 for H. bacteriophora H06 in proper concentrations. Furthermore, it was discovered that increased recovery rate, hermaphrodite numbers and eggs in the hermaphrodites may contribute to the improved IJ yields of H. bacteriophora H06 in DMSO-supplemented liquid medium. Compared with the control flasks, the IJ yields from the flasks containing 0.01 % DMSO were 15 % and 35 % higher for S. carpocapsae All and H. bacteriophora H06 respectively in 15 days. The cost for ascarosides and DMSO is almost negligible. The results would provide practical technology for low-cost commercial production of these nematodes for pest management program.


Asunto(s)
Nematodos , Rabdítidos , Animales , Dimetilsulfóxido , Control Biológico de Vectores , Feromonas
9.
J Helminthol ; 95: e54, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34505559

RESUMEN

Liquid culture is the most scalable technology for the industrial production of entomopathogenic nematodes. Variability of the recovery after inoculation into cultures of Photorhabdus luminescens remains a persistent problem in the mass production of Heterorhabditis sp. In order to enhance infective juvenile (IJ) recovery and improve nematode population management, we analysed the correlation between the nematode Heterorhabditis megidis (strain KV - 136) development in liquid cultures, the density of bacteria of P. luminescens and the culture agitation speed. Analyses focused on the impact of different agitation speeds (160 rpm and 200 rpm) on the dynamics of population growth of H. megidis in liquid cultures at constant biotic and abiotic parameters (initial dose of nematodes introduced to the culture 2300 IJs/ml, temperature 25°C, the number of bacterial colonies 0.3 × 107/ml). The performed experiments showed that the agitation speed of 200 rpm favourably affected the density of bacteria of P. luminescens (24.14 × 107/ml). High density of bacteria at this agitation speed resulted in an earlier (on the fifth day of the culture) maximum increase in the number of hermaphroditic individuals (1239.6 H/ml) than in the culture at an agitation speed of 160 rpm.


Asunto(s)
Nematodos , Photorhabdus , Animales , Humanos , Dinámica Poblacional , Strongyloidea , Simbiosis
10.
World J Microbiol Biotechnol ; 37(9): 154, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34398297

RESUMEN

Bacillus thuringiensis (Bt) (Bacillales:Bacillaceae) is a gram-positive bacterium that produces spores, several virulence factors and insecticidal toxins, making this microorganism the most used biopesticide worldwide. The use of inert supports such as polyurethane foam (PUF) in solid cultures has been a great alternative to produce various metabolites, including those produced by Bt. In this study we compared the yields, productivity and quality of the spores by two wild strains of Bt, (Y15 and EA3), grown in media with high substrate concentration in both culture systems: liquid and solid (PUF as solid inert support). Both strains showed 2.5- to 30-fold increases in spore production and productivity in solid culture, which showed an even greater increase when considering the spores retained in the PUF observed by scanning electron microscopy. Moreover, spore produced in solid culture showed up to sevenfold higher survival after a heat-shock treatment, relative to spores from liquid culture. The infectivity against larvae of Galleria mellonella (Lepidoptera:Pyralidae) improved also in spores from solid cultures. This comparison showed that the culture of Bt on solid support has clear advantages over liquid culture in terms of the production and quality of spores, and that those advantages can be attributed only to the culture system, as the same media composition was used in both systems.


Asunto(s)
Bacillus thuringiensis/fisiología , Poliuretanos/química , Esporas Bacterianas/crecimiento & desarrollo , Animales , Bacillus thuringiensis/patogenicidad , Técnicas Bacteriológicas , Medios de Cultivo/química , Larva/microbiología , Lepidópteros/microbiología , Microscopía Electrónica de Rastreo
11.
Biotechnol Bioeng ; 117(12): 3968-3985, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32710642

RESUMEN

Monoxenic liquid culture is the most suitable technology for scaling up to industrial production of entomopathogenic nematodes (EPNs); however, the variability of the yield production remains a current problem in the process. The aim of this study was to analyze the parameters and criteria for EPN production in liquid culture based on scientific and technological knowledge from the last two decades. While experimental research has permitted the yield production of Heterorhabditis bacteriophora (362 × 103 infective juveniles [IJs]/ml) and Steinernema carpocapsae (252 × 103 IJs/ml), simultaneously, theoretical approaches have contributed to the understanding of the culture process, based on biological parameters of the bacterium-nematode complex and hydrodynamic and rheological parameters of the complex gas-liquid-solid system. Under this interdisciplinary research approach, bioprocess and biosystem engineering can contribute to design the various control strategies of the process variables, increase the productivity, and reduce the variability that until now distinguishes the in vitro production of EPNs by the liquid culture.


Asunto(s)
Control Biológico de Vectores , Rabdítidos/crecimiento & desarrollo , Animales , Reología
12.
New Microbiol ; 43(1): 13-16, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32334488

RESUMEN

The long incubation time required for Mycobacteria detection may allow cultures to become overgrown by contaminating organisms. Therefore, samples need to be decontaminated before solid and liquid culture. MYCO-TB is a ready-to-use digestion and decontamination kit with single-sample formulation developed by Copan. Sample processing time (3 minutes) is shorter than that of other commercial kits. The aim of this study was to compare the performance of MYCO-TB with MycoPrep, both based on N-acetyl-Lcysteine and sodium hydroxide solution, in terms of culture contamination and Mycobacterial detection by culture. We tested 162 respiratory samples: the overall proportions of contamination of both liquid and solid media were 1.8% for MYCO-TB and 1.8% for MycoPrep. Mycobacterial growth was detected without significant differences in times to positivity (TTP) in liquid culture: 10.5 days for MYCO-TB and 11.1 days for MycoPrep. Samples decontaminated with MYCO-TB were suitable for molecular assays such as Xpert MTB/RIF Ultra and GenoType CMdirect. Extending decontamination times (up to 10 minutes) with MYCO-TB of 20 Mycobacteria-positive specimens did not produce any difference in TTP in liquid culture or in Ultra IS1081/IS6110 probe Ct values. In conclusion, the MYCO-TB kit proved to be effective for the rapid digestion and decontamination of respiratory materials for the detection of Mycobacteria, making it possible to reduce the manual skills required and lower the risk of contamination. Longer decontamination time could be used for samples with a high level of contamination, such as those from cystic fibrosis patients.


Asunto(s)
Técnicas Bacteriológicas , Mycobacterium tuberculosis , Juego de Reactivos para Diagnóstico , Tuberculosis , Técnicas Bacteriológicas/métodos , Técnicas Bacteriológicas/normas , Descontaminación , Humanos , Mycobacterium tuberculosis/aislamiento & purificación , Juego de Reactivos para Diagnóstico/normas , Sensibilidad y Especificidad , Tuberculosis/diagnóstico , Tuberculosis/microbiología
13.
Appl Microbiol Biotechnol ; 103(4): 1681-1691, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30648190

RESUMEN

Cordyceps spp. is the herbal medication initially used in China and has been reported as the unique resource of cordycepin. Cordycepin exhibits many health benefits, including anti-photoaging and anti-pigmentation; therefore, it potentially is a bioactive ingredient of cosmetic products. In order to enrich cordycepin content in Cordyceps, two artificial cultivation procedures, which are solid-state fermentation and liquid culture, were developed and optimized. The aim of this review is to illustrate cordycepin biosynthesis pathway in Cordyceps, and its bioactivity for cosmeceutical applications, as well as comparing the two different cultivation procedures. The basic model of artificial cultivation of Cordyceps is introduced; meanwhile, the potential application of modern biotechnology to the artificial cultivation is also discussed. This review should be of interest to the readers for the development of cordycepin bioproduction in order to be applied in cosmeceutical industry and some other uses.


Asunto(s)
Antifúngicos/metabolismo , Antineoplásicos/metabolismo , Cordyceps/metabolismo , Cosmecéuticos/metabolismo , Desoxiadenosinas/metabolismo , Vías Biosintéticas/genética , Cordyceps/crecimiento & desarrollo , Fermentación , Microbiología Industrial/métodos , Mutágenos/metabolismo
14.
Med J Armed Forces India ; 74(3): 220-226, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30093764

RESUMEN

BACKGROUND: Manual Mycobacterium growth indicator tube (MGIT) was evaluated for isolation and drug susceptibility testing (DST) of Mycobacterium tuberculosis (MTB) for its implementation in laboratories with low and medium volume. METHODS: 1018 consecutive clinical specimens were processed using manual MGIT and conventional Lowenstein-Jensen (LJ) culture. Results obtained for culture positivity were analyzed taking combined reference of positivity by either solid or liquid culture. All positive cultures were identified and DST to first line drugs was performed by manual MGIT and 1% proportional method on LJ media. Performance of manual MGIT for DST was compared to conventional DST on LJ media. RESULT: Of the total 220 culture positive samples 93.9% were isolated in MGIT while 75.7% in LJ taking combined reference of positivity by either solid or liquid culture. Turn around time for isolation of MTB was significantly less for MGIT as compared to LJ. There was good agreement between manual MGIT and 1% proportional method on LJ media for DST to first line drugs. Turnaround time from inoculation to DST results for smear positive and smear negative cases using manual MGIT was 20.2 and 30.1 days respectively. The total cost for isolation, identification and DST in manual MGIT for smear positive and smear negative cases was INR 2350 and INR 2700 respectively. CONCLUSION: It is feasible to implement manual MGIT in low to medium volume laboratory that already has experience with culture provided adequate biosafety measures and appropriate training of laboratory staff are taken care of.

15.
BMC Infect Dis ; 17(1): 663, 2017 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-28969600

RESUMEN

BACKGROUND: Maintaining the quality of clinical specimens for tuberculosis (TB) testing is a major challenge in many high TB burden-limited resources countries. Sample referral systems in low and middle income countries are often weak and the maintenance of the cold-chain challenging and very costly for TB programs. The development of transport media allowing the preservation of samples without refrigeration is critical for increasing access to TB diagnostic services and for reducing the costs related to testing. METHODS: We evaluated the performance of OMNIgene-SPUTUM (OM-S) reagent for the maintenance of Mycobacterium tuberculosis (MTB) viability in sputum samples in the absence of refrigeration and its capacity to stabilize nucleic acid for molecular testing. A total of 329 sputum specimens from presumptive TB cases collected at the National Reference Laboratory in Tirana, Albania, were either decontaminated by a conventional method or processed with OM-S reagent and stored at room temperature. Samples in OM-S were shipped to the Supranational Reference Laboratory in Milan, Italy, at various times and processed for liquid culture. RESULTS: Our data show that OM-S maintains MTB viability for at least three weeks in the absence of refrigeration and improves the quality of culture resulting in a contamination rate lower than 0.5%. However, a significant delay in the time to culture positivity was observed for samples stored for more than two weeks in OM-S. CONCLUSIONS: Overall, OM-S offers multiple benefits both at laboratory and TB national program level by increasing the availability to quality diagnostics, promoting access to health care services and strengthening TB patient care especially in hard to reach populations.


Asunto(s)
Mycobacterium tuberculosis , Manejo de Especímenes/métodos , Esputo/microbiología , Tuberculosis/microbiología , Humanos , Indicadores y Reactivos , Estudios Prospectivos , Sensibilidad y Especificidad , Temperatura , Tuberculosis/diagnóstico
16.
Am J Physiol Lung Cell Mol Physiol ; 309(5): L475-87, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26115671

RESUMEN

Cystic fibrosis (CF) has a profound impact on airway physiology. Accumulating evidence suggests that intercellular junctions are impaired in CF. We examined changes to CF transmembrane conductance regulator (CFTR) function, tight junctions, and gap junctions in NuLi-1 (CFTR(wt/wt)) and CuFi-5 (CFTR(ΔF508/ΔF508)) cells. Cells were studied at air-liquid interface (ALI) and compared with primary human bronchial epithelial cells. On the basis of fluorescent lectin binding, the phenotype of the NuLi-1 and CuFi-5 cells at week 8 resembled that of serous, glycoprotein-rich airway cells. After week 7, CuFi-5 cells possessed 130% of the epithelial Na(+) channel activity and 17% of the CFTR activity of NuLi-1 cells. In both cell types, expression levels of CFTR were comparable to those in primary airway epithelia. Transepithelial resistance of NuLi-1 and CuFi-5 cells stabilized during maturation in ALI culture, with significantly lower transepithelial resistance for CuFi-5 than NuLi-1 cells. We also found that F508del CFTR negatively affects gap junction function in the airway. NuLi-1 and CuFi-5 cells express the connexins Cx43 and Cx26. While both connexins were properly trafficked by NuLi-1 cells, Cx43 was mistrafficked by CuFi-5 cells. Cx43 trafficking was rescued in CuFi-5 cells treated with 4-phenylbutyric acid (4-PBA), as assessed by intracellular dye transfer. 4-PBA-treated CuFi-5 cells also exhibited an increase in forskolin-induced CFTR-mediated currents. The Cx43 trafficking defect was confirmed using IB3-1 cells and found to be corrected by 4-PBA treatment. These data support the use of NuLi-1 and CuFi-5 cells to examine the effects of F508del CFTR expression on tight junction and gap junction function in the context of serous human airway cells.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Uniones Comunicantes/patología , Mucosa Respiratoria/metabolismo , Uniones Estrechas/patología , Adulto , Señalización del Calcio/genética , Línea Celular , Colforsina/farmacología , Conexina 26 , Conexina 43/biosíntesis , Conexina 43/metabolismo , Conexinas/biosíntesis , Conexinas/metabolismo , Fibrosis Quística/genética , Fibrosis Quística/patología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/biosíntesis , Células Epiteliales/metabolismo , Uniones Comunicantes/genética , Humanos , Masculino , Fenilbutiratos/farmacología , Transporte de Proteínas/efectos de los fármacos , Mucosa Respiratoria/citología , Uniones Estrechas/genética
17.
Physiol Mol Biol Plants ; 20(1): 81-7, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24554841

RESUMEN

An efficient and improved method for in vitro propagation of mature tree of Dalbergia sissoo, an ecologically and commercially important timber yielding species, has been developed through axillary shoot proliferation. Bud breaking occurred from nodal shoot segments derived from rejuvenated shoots produced during early spring from a 20-25-year-old lopped tree, on MS medium containing 8.88 µM benzylaminopurine (BAP). Multiple shoots differentiated (20-21shoots/node) on re-culture of explants on half-strength agar gelled amended MS medium with a combination of 2.22 µM of BAP and 0.002 µM of thidiazuron (TDZ) with 1.0 mM each of Ca(NO3)2, K2SO4, KCl, and NH4(SO4)2. The maximum shoot multiplication (29-30 shoots/node) was achieved on subculturing in the above mentioned but liquid medium. Furthermore, the problem of shoot tip necrosis and defoliation observed on solid medium were overcome by the use of liquid medium. Ex vitro rooting was achieved on soilrite after basal treatment of microshoots with 984 µM of indole-3-butyric acid (IBA) for 2 min. About 90 % microshoots were rooted on soilrite within 2-3 weeks under the greenhouse conditions. From 20 nodal shoot segments, about 435 hardened plants were acclimatized and transplanted. This is the first report for rapid in vitro propagation of mature trees of D. sissoo on liquid medium followed by ex vitro rooting.

18.
Cureus ; 16(6): e61542, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38957255

RESUMEN

Background The diagnosis of Mycobacterium avium-intracellulare complex lung disease (MAC-LD) requires two or more positive sputum cultures. Few reports have examined the usefulness of adding liquid culture to conventional solid culture for diagnosing MAC-LD. Methods A retrospective, cohort study of patients examined at Kurashiki Central Hospital in Japan with a confirmed diagnosis of MAC-LD between January 1, 2002, and June 20, 2021, was conducted. The primary endpoint was the culture positivity rate, which was compared between the liquid and Ogawa culture media in patients who underwent sputum culture using both methods. Secondary endpoints were the culture positivity rate in smear-positive specimens and the positivity rate by radiological type. Results The study, which involved 351 patients and 702 specimens, showed a higher positivity rate for liquid culture (n=690, 98.3%) than Ogawa culture (n=315, 44.9%). Overall, 265 patients (75.5%) would have had delayed MAC-LD diagnosis without liquid medium being used. Of the 95 smear-positive specimens, 71 (74.7%) were positive on both cultures, whereas 24 (25.3%) were positive only on liquid culture. The positivity rate of Ogawa culture varied by radiological type. Conclusions Liquid culture is more valuable for the early diagnosis of MAC-LD than Ogawa culture.

19.
Sci Total Environ ; 950: 175136, 2024 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-39084374

RESUMEN

Precise and rapid methods are needed to improve monitoring approaches of L. pneumophila (Lp) in cooling towers (CTs) to allow timely operational adjustments and prevent outbreaks. The performance of liquid culture (ASTM D8429-21) and an online qPCR device were first compared to conventional filter plate culture (ISO 11731-2017), qPCR and semi-automated qPCR at three spiked concentrations of Lp (serogroup 1) validated by flow cytometry (total/viable cell count). The most accurate was qPCR, followed by liquid culture, online and semi-automated qPCR, and lastly, by a significant margin, filter plate culture. An industrial CT system was monitored using liquid and direct plate culture by the facility, qPCR and online qPCR. Direct plate and liquid culture results agreed at regulatory sampling point, supporting the use of the faster liquid culture for monitoring culturable Lp. During initial operation, qPCR and online qPCR results were within one log of culture at the primary pump before deviating after first cleaning. Other points revealed high spatial variability of Lp. The secondary pumps and chiller had the most positivity and highest concentrations by both qPCR and liquid culture compared to the basin and infeed tank. Altogether, this suggests that results from monthly compliance sampling at a single location with plate culture are not representative of Lp risks in this CT due to the high temporal and spatial variability. The primary pump, rather than the CT basin, should be designated for sampling, as it is representative of the health risk. An annual multi point survey of the system should be conducted to identify and target Lp hot spots. Generally, a combination of liquid culture for compliance and frequent qPCR for process control provides a more agile and robust monitoring scheme than plate culture alone, enabling early treatment adjustments, due to lower limit of detection (LOD) and turnover time.


Asunto(s)
Monitoreo del Ambiente , Legionella pneumophila , Microbiología del Agua , Monitoreo del Ambiente/métodos , Aire Acondicionado , Reacción en Cadena en Tiempo Real de la Polimerasa
20.
Mol Biotechnol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658470

RESUMEN

Cordyceps, an entomopathogenic fungus belonging to the Ascomycota phylum, is a familiar remedial mushroom that is extensively used in the traditional medicinal system, especially in South Asian nations. The significance of this genus' members in a range of therapeutic and biotechnological applications has long been acknowledged. The exceedingly valuable fungus Ophiocordyceps sinensis (Cordyceps sinensis) is found in the alpine meadows of Bhutan, Nepal, Tibet, and India, where it is severely harvested. Driven by market demand and ecological concerns, the study highlights challenges in natural C. sinensis collection and emphasizes the shift towards sustainable artificial cultivation methods. This in-depth review navigates Cordyceps cultivation strategies, focusing on C. sinensis and the viable alternative, C. militaris. The escalating demand for Cordyceps fruiting bodies and bioactive compounds prompts a shift toward sustainable artificial cultivation. While solid-state fermentation on brown rice remains a traditional method, liquid culture, especially submerged and surface/static techniques, emerges as a key industrial approach, offering shorter cultivation periods and enhanced cordycepin production. The review accentuates the adaptability and scalability of liquid culture, providing valuable insights for large-scale Cordyceps production. The future prospects of Cordyceps cultivation require a holistic approach, combining scientific understanding, technological innovation, and sustainable practices to meet the demand for bioactive metabolites while ensuring the conservation of natural Cordyceps populations.

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