Use Of Liquid Medium Research Articles

Femtosecond laser-induced dewetting of sub-10-nm nanostructures on silicon in ambient air

To realize nanoscale manufacturing based on laser direct writing technology, objective lenses with high numerical apertures immersed in water or oil are necessary. The use of liquid medium restricts its application in semiconductors. Achieving nanoscale features on silicon by laser direct writing in a low refractive index medium has been a challenge. In this work, a microsphere assisted femtosecond laser far-field induced dewetting approach is proposed. A reduction in the full-width at half-maximum of the focused light spot is realized by modulating tightly focused light through microspheres and achieving a minimum feature size of 9 nm on silicon in ambient air with energy smaller than the ablation threshold. Theoretical analysis and numerical simulation of laser processing are performed based on a two-temperature model. Furthermore, we explored the potential of femtosecond laser-induced dewetting in nanolithography and demonstrated its ability to achieve an arbitrary structure on silicon. Our work enables laser-based far-field sub-10-nm feature etching on a large-scale, providing a novel avenue for nanoscale silicon manufacturing.

The Effect of the Type of Planting Media and The Addition of O2 Nanobubbles on the Growth of Dendrobium burana Green × Ong Ang Ai Boon Orchid Plantlets in Vitro

Dendrobium orchids come in a variety of colors, shapes, and beauty that are in great demand. The process of growing orchids requires special handling of an appropriate growing environment, such as proper planting media and nutrients that can stimulate orchid growth. This type of thin liquid film media is the use of liquid media with an immersion system while vermiculite and perlite media have almost the same properties. However, vermiculite has a higher water absorption capacity than perlite. Nanobubbles are bubbles with 1-100 nm that can live more stably in water. This study aims to influence the type of media and the addition of Nanobubbles O2 on the growth of Dendrobium burana Green × Ong Ang Ai Boon orchid plantlets. This research was carried out from November to December 2022 at the PT. Java Indo Arjuna Singosari, Malang. This study used a completely randomized design (CRD) with 10 treatments, namely solid MS, gaviota solid, thin liquid film, thin liquid film + NBs O2, vermiculite, vermiculite + NBs O2, perlite, perlite + NBs O2, vermiculite + Perlite, vermiculite + perlite + NBs O2 with 4 replications. The data were analyzed descriptively and the Manova test. The results showed that the vermiculite + NBs O2 treatment had the potential to increase the length of plantlets by 13.80 mm, the wet weight of plantlets by 0.30 g, the percentage of live plantlets by 100% whereas in the vermiculite + perlite treatment has the potential for the first root growth to appear, namely 5 HST. The vermiculite treatment had the potential to increase the highest number of leaves by 5 leaves, whereas in the leaf color treatment the solid MS treatment had a more intense green color.

Secondary Embryogenesis of Linaloe in Temporary Immersion Bioreactor-Type RITA®.

The linaloe [Bursera linanoe (La Llave) Rzed, Calderon and Medina] is an endemic species of Mexico, representative of the low deciduous forest of the states of Guerrero, Puebla, Morelos, and Oaxaca, and has been of great economic importance for the people, mainly for the artisanal use of its aromatic wood that is used to make boxes, trunks, and furniture that are manufactured in Olinala, Guerrero, Mexico; and industrial, thanks to the fine aroma of its essential oil (linalool), which is used in the manufacture of perfumes and pharmaceuticals. Overexploitation has endangered the species in recent years, and propagation by seed and/or cuttings has produced very poor results compared to those obtained with other recalcitrant Bursera species. The protection of endangered species makes urgent the need to propose new alternatives for its propagation. Somatic embryogenesis is a reliable and feasible technique, including induction, maintenance, multiplication, and maturation of embryos, often in semisolid culture media; however, the recent use of liquid media has allowed semi-automation in temporary immersion bioreactors, for example, the RITA® system, which favors both the multiplication rate and the final conversion to seedlings.

Bioreactor systems for micropropagation of plants: present scenario and future prospects.

Plant micropropagation has been adapted in the fields of agriculture, horticulture, forestry, and other related fields for large-scale production of elite plants. The use of liquid media and adoption of bioreactors have escalated the production of healthy plants. Several liquid-phase, gas-phase, temporary immersion, and other modified bioreactors have been used for plant propagation. The design, principle, operational mode, merits, and demerits of various bioreactors used for the regeneration of propagules, such as bulblets, cormlets, rhizomes, microtubers, shoots (subsequent rooting), and somatic embryos, are discussed here. In addition, various parameters that affect plant regeneration are discussed with suitable examples.

Effect of cavitated husks on the metabolome of fermentation end products, microbiome and physicochemical parameters of the rumen (i<i>n vitro</i>)

Relevance. Today, a significant place in the feeding of farm animals is given to such inexpensive waste from the oil extraction industry as sunflower husk. In this regard, one of the promising and modern methods for optimizing feed production can be the use of liquid media activated in various ways, in combination with ultrasonic treatment. Materials and methods. The object of research was crushed sunflower husk (1.0 mm) (sample 1), as well as husk sonicated (cavitated) in hydromodules with water (in the ratio “husk: water” 1 : 3 (sample 2)), and with lactic acid (“husk: lactic acid” 1 : 3 (sample 3)). The obtained samples were used in in vitro studies with rumen fluid in the “Daisy D200I” incubator (“Ankom Technology”, USA). The following indicators of the exchange of nitrogenous metabolites in the cicatricial contents were determined – residual and total nitrogen by the Kjeldahl method according to the method of K. K. Akhazhanova (2016); ammonia nitrogen – by microdiffusion method according to Conway. The taxonomic composition of the scar fluid was determined by NGS-sequencing using the “MiSeq device” (“Illumina”, USA). Research results. Data analysis showed that the use of cavitated sunflower husk increases the digestibility of dry matter by 19.0 % (Р ≤ 0.01), and cavitated together with lactic acid husk – by 20.7 % (Р ≤ 0.01) in comparison with crushed husk. When incubating cavitated sunflower husk and cavitated together with lactic acid sunflower husk, there were a decrease in the number of archaea, in particular the class Methanobacteria, by 23.73 % and 20.36 % (Р ≤ 0.05) and an increase in the number of bacteria of the phyla Bacteroidetes by 10.2 % and 11.27 %, Firmicutes – by 4.66 % and 6.86 % relative to the use of crushed husk.

Microbiological Diagnosis of Osteoarticular Infections: Comparison between BacT/Alert Bottles and Schaedler Broth.

ABSTRACTMicrobiological diagnosis of osteoarticular infections (OAIs) is based on culture on several media. Experts recommend the use of liquid media, such as Schaedler broth, but many laboratories use blood culture media with automated detection instead for convenience. We aimed to evaluate the performance of culturing in BacT/Alert (bioMérieux) bottles for the microbiological diagnosis of OAI versus culturing in Schaedler broth. This prospective study was conducted on all osteoarticular specimens sent to the microbiology laboratories of the Versailles and Diaconesses Croix Saint-Simon hospitals between October 2016 and February 2017. Each sample was inoculated onto solid agar, into BacT/Alert bottles incubated for 14 days, and into a Schaedler broth incubated for 14 days with daily reading. The gold standard was defined as follow: OAI was diagnosed for a patient if at least two samples were positive for a nonskin microorganism and at least three for a cutaneous species. The times to detection were compared. A total of 1,616 specimens from 349 patients were collected. BacT/Alert bottles were significantly more sensitive than the Schaedler process for OAI diagnosis (114/135 OAI detected by BacT/Alert bottles; 91/135 OAI detected by Schaedler broth; +17.0% [95% confidence interval {CI}, 6.8%, 27.3%]; P = 0.0004). The time to detection was significantly shorter using BacT/Alert bottles (2.0 ± 2.2 days) than using Schaedler broth (4.6 ± 3.6 days, P < 0.0001). The culture of osteoarticular specimens in BacT/Alert bottles allows bacterial enrichment with an automated detection of positivity. Their use decreased detection time and increased sensitivity, making it a useful tool for the diagnosis of OAI that should be included among the recommended media.IMPORTANCE Microbiological diagnosis of OAI is based on culture on several media. French experts recommend the use of liquid media such as Schaedler broth, but many laboratories use blood culture media with automated detection in substitution because it is more convenient. We report here a prospective multicentric study evaluating the performance of culture in BacT/Alert (bioMérieux) bottles for microbiological diagnosis of OAI in comparison with culture in Schaedler broth. A total of 1,616 osteoarticular specimens from 349 patients were collected and inoculated onto agar, into BacT/Alert aerobic and anaerobic bottles, and into a Schaedler broth. BacT/Alert bottles were significantly more sensitive than the Schaedler process for OAI diagnosis (+17.0% [95% CI, 6.8%, 27.3%], P = 0.0004). The time to detection was significantly shorter for the BacT/Alert bottles (2.0 ± 2.2 days) than for Schaedler broth (4.6 ± 3.6 days, P < 0.0001). This study suggests that the use of BacT/Alert bottles should be recommended in microbiological diagnosis of OAI.

Self‐Contained Focus‐Tunable Lenses Based on Transparent and Conductive Gels

AbstractFocus‐tunable lenses have found wide applications in optical communications, medical diagnostics, and consumer electronics. However, many focus‐tunable lenses have complex architecture, slow response, and low focal length variation, due principally to the separate design of optical path and activation mechanism and the use of liquid medium. Herein, a new self‐contained focus‐tunable lenses based on transparent and conductive gels are developed. The plano‐convex gels, acting both as lens and electrodes of actuator, with desirable curvature are precisely patterned by inkjet 3D printing. When a voltage is applied to the gel lenses, the elastomer membrane is stretched radially by Maxwell force, resulting in a reduction of lens thickness that corresponds to an increase of curvature radius. Therefore, a large focal length variation of 32–81% and a fast response speed of 80–153 ms are obtained. It is believed that this self‐contained focus‐tunable gel lenses can find many applications in portable optical devices, particularly suitable for space‐constrained tasks.

Comparison of LJ Medium and BACTEC MGIT 960 Culture System for the Diagnosis of Tuberculosis

Introduction: Sputum negative pulmonary Tuberculosis (TB) is a major public health problem. So, the emergence of new techniques for a more precise and rapid microbiological identification of Mycobacterium tuberculosis in clinical samples is of great importance to improve the management of TB. Aim: To determine and compare the sensitivity and turnaround time for Mycobacterium tuberculosis detection by the BACTEC Mycobacteria Growth Indicator Tube (MGIT) 960 system, Lowenstein Jensen (LJ) medium and Ziehl-Neelsen (ZN) staining. Materials and Methods: An Institution based, observational, cross-sectional study was conducted at Rajendra Institute of Medical Sciences (RIMS), Ranchi, Jharkhand, India, from July 2013-March 2016. Sputum, pericardial fluid, pleural fluid, peritoneal fluid, pus and endometrial tissue samples were collected from 80 patients of suspected TB cases. All were Acid-Fast stained by ZN staining method and cultured on solid culture LJ medium and on liquid medium (MGIT). Data was analysed using Statistical Package for the Social Sciences (SPSS) software, Version 20.0 (SPSS Inc, Chicago, IL, USA). Fisher’s-Exact test was used to show association of categorical variables. Non-parametric Mann-Whitney U test was used to show median difference of non-normally distributed continuous variables of two groups. Results: Out of the 80 samples, 41 cases were positive by either of the all methods. The positive specimen for ZN staining, LJ media and MGIT were 21, 29 and 41 cases respectively. The mean Time To Detection (TTD) was shorter for MGIT system than LJ media. Both LJ medium and MGIT 960 detected all cases of sputum smear positive cases and in addition significantly higher number than ZN stain in sputum smear negative cases. MGIT 960 detected significantly higher number of cases of sputum negative cases than LJ Media. The mean TTD was also significantly shorter in case of smear positive cases than the smear negative cases by both the solid and liquid culture mediums. Conclusion: The use of liquid media (MGIT) is more accurate and rapid method for the diagnosis of TB. The combination of more than one method is also highly recommended for rapid detection and early treatment of TB.

Prospects of applying sunflower sludge after cavitational processing in poultry breeding

Modern trends in science and technology, from the viewpoint of the concept of state policy on the field of nutrition, as well as the implementation of anti-crisis measures in the Russian agricultural sector, should be oriented towards the development of competitive food and feed products of a new generation that meets all international standards. The use of liquid media activated by variant ways in complex with the rational hydromechanical and ultrasonic exposure might be the most promising and the most modern methods of process optimization for feed production. Nowadays the technology of processing a high-viscous liquid media with gaining feed products of preset properties includes both electrochemical processing and cavitative disintegration. Our research revealed that addition of cavitation-treated products of sunflower sludge into the diet of broilers in the amount of 6% of the total feed mass positively affects the digestive extent in the growth period. Moreover, the introduction of cavitation-treated products of sunflower sludge with zeolite to the ration bears a positive effect on reducing consumption of feed per 1 kg of the live weight gain from 2.04 to 1.46 kg per capita, which improves the productive qualities.

Feasibility of the new method for orchid in vitro rooting using liquid and chemical sterilized culture medium under different sucrose concentration

Abstract The in vitro propagation of orchids is the only commercial large scale technique to obtain healthy and high quality plantlets with clonal origin. The use of new technologies in plant tissue culture systems could lead to efficiency increases and costs reduction of micropropagation systems. The main actual micropropagation system is based on semi-solid culture media solidified using agar, followed by sterilization using autoclaving, and cultivation under photomixotrophic conditions using sucrose as main source of energy to plant in vitro culture. We proposed in this study the use of new micropropagation system using chemical sterilized liquid medium using polyurethane foam as support and LED source of light in rooting stage of Miltassia ‘Shelobie Tolkien’. Thus, the objective of this research was to test different concentrations of sucrose, comparing the conventional semi-solid agar-based culture medium (control) and the use of liquid medium with polyurethane foam support. The following sucrose concentrations were used: 0, 7.5, 15, 22.5 and 30 g L-1. The experiment was conducted in a 2 × 5 factorial, in a completely randomized design with ten replications each over a total period of 105 days of cultivation. The chemical sterilization using ClO2 showed 100% of decontamination in all treatments. The use of liquid media with polyurethane foam showed better results than plants cultivated in agar medium, and can be used for replace agar-based for orchid in vitro rooting.

Thermal performance comparison of three sensible heat thermal energy storage systems during charging cycles

Experimental results evaluating and comparing three sensible heat storage systems are presented during charging cycles with three different flow-rates of 4 ml/s, 8 ml/s and 12 ml/s respectively. Two packed storage systems using Sunflower Oil as the heat transfer fluid with two particle diameters (10.5 mm and 31.9 mm) are compared with an oil only storage tank. The oil storage system charges up fastest, followed by the small pebbles thermal energy storage (TES) and lastly by the large pebbles TES due its lower thermal mass. The small pebbles TES has a faster rate of temperature rise because the small pebbles reach thermal equilibrium more easily than the big pebbles which normally experience temperature drops. The purpose of this work is to determine the thermal performance of pebble packed beds using Sunflower Oil as the heat transfer fluid (HTF) in the medium temperature ranges suitable for cooking applications. Three thermal performance parameters are evaluated during charging cycles which are the energy rate, exergy rate and stratification number. Higher charging energy and exergy rates are obtained with small pebbles TES system making it the best storage system in terms of energy and exergy rates. Exergy rates are found to be dependent on temperature differences between the top and the bottom of the storages and on average storage temperatures. Charging flow-rates have no clear relationship with exergy rates. Thermal stratification in TES systems that employ the use of liquid media as storage materials improve the energy efficiency of such thermal storages. Stratification occurs when the lower density hot liquid rises to the top of the storage tank while the higher density cold liquid sinks to the bottom. Stratification number profiles of the experiments conducted are seen to rise and drop during charging cycles for all thermal storage systems. The oil TES system shows the fastest rise and drop of the stratification number due to its lower thermal mass. Generally, the slowest rate of drop in the stratification number profiles is seen with the large pebbles TES system for all flow-rates. This suggests that more quality useful energy is stored in this system of large pebbles inspite of the fact that it charges up with a lower initial rate. The small pebbles TES performed better in terms of the thermal performance parameters evaluated in this study.

Evaluation of immune responses in mice and sheep inoculated with a live attenuated Brucella melitensis REV1 vaccine produced in bioreactor

The Brucella melitensis REV1 vaccine is the most widely employed vaccine for prophylaxis against brucellosis in sheep and goats. The objective of vaccination is disease control in herds or preventing infection in farms. In this study, we produced REV1 vaccine with a protocol, based on the use of liquid medium in a bioreactor, that resulted efficient, safe, relatively fast, and cost-effective. The live attenuated vaccine produced was tested in mice and sheep to investigate its immunogenicity and efficacy. Seventy-two female BALB/c mice were obtained and subdivided in 2 groups, one was stimulated with 1 × 106 colony-forming units (CFUs) of B. melitensis while the other with physiological solution alone and acting as control group. Furthermore, 25 sheep were subdivided into 5 groups: four were inoculated with a B. melitensis dose, ranging from 0.6 × 109 and 3.2 × 109 CFUs and the other was the control group. In addition, a serological diagnosis was performed for sheep by rapid serum agglutination and the complement-fixation test. Immunocompetent cells from both experiment were collected at different times post vaccination and immunostained to evaluate innate and adaptive-immune responses. In mice flow cytometry was used to detect macrophages, T lymphocytes, dendritic cells, memory cells, naïve cells, natural killer cells, major histocompatibility complex type II, B lymphocytes, regulatory T lymphocytes, T helper lymphocytes, cytotoxic T lymphocytes and recently activated CD4+ and CD8+ lymphocytes. In sheep, macrophages, T helper cells, cytotoxic T lymphocytes, regulatory T lymphocytes, dendritic cells, memory cells and naïve lymphocytes, by the same method, were analyzed. The results showed, both in mice and sheep, that the live, attenuated REV1 vaccine stimulated all immunocompetent cells tested, with a balanced innate and adaptive response. In the sheep experiment, the administered vaccine dose was very important because, at the lower doses, immunological tolerance tended to disappear, while, at the highest dose, the immunological tolerance remained active for a long period. In our experimental conditions, the optimal vaccine dose for sheep was 3.2 × 109 CFUs, although a good immune response was found using a dose of 1.6 × 109 CFUs. The vaccine produced in this study could be extensively employed in developing countries to control the brucellosis in sheep and goats.

Cost Effective Techniques for In Vitro Propagation of Two Varieties of Sugarcane

The present study was carried out to optimize cost effective in vitro protocol for mass propagation of two commercial sugarcane varieties grown in Maharashtra, India. The effect of different cytokinins and auxins on in vitro initiation, multiplication and rooting was investigated in sugarcane (Saccharum spp.) varieties; Co86032 and CoC671. Shoot tip explants comprising of apical meristems and 1-2 leaf primordia were carefully excised from the apical region and inoculated on MS basal liquid medium supplemented with different concentrations and combinations of Kinetin and BAP. Only initiation medium was sterilized by autoclaving and further shoot multiplication, rooting was done on medium sterilized with sodium hypochlorite (4% w/v available chlorine) at the concentrations 0.05% corresponding to total active chlorine concentration 0.002% in the medium. With regard to shoot initiation, variety Co86032 showed maximum shoot formation (96.67%) on MS medium supplemented with BAP (0.2mg/L) and Kinetin (0.1mg/L) with 3% sucrose and 10% CW on the other hand variety CoC671 showed maximum shoot formation (93.33%) on MS medium supplemented with only Kinetin( 0.5mg/L), 3% sucrose, 10% CW. The best response in terms of shoot multiplication for variety Co86032 was observed on MS medium with BAP (0.2mg/L) and Kinetin (0.1mg/L)with 3% commercial sugar while for variety CoC671 it was observed on MS medium with Kinetin and BAP (0.2mg/L each) and 3.0% commercial sugar. Variety Co86032 produced multiple shoots with an average number of 31.25±0.99 shoots per bottle while variety CoC671 produced 27.72±0.66 shoots per bottle. For rooting, the multiplying shoots were separated in smaller groups and transferred on half strength MS liquid medium containing different concentrations of NAA or IBA with different concentrations of commercial sugar. Half strength MS basal medium with NAA (5.0 mg/L) and 5.0% commercial sugar induced highest rooting (84.44%) with average root number per shoot of 8.49 ±0.25 in Co86032. In variety CoC671, half strength MS basal medium with IBA (5.0 mg/L) and 5.0% commercial sugar induced highest rooting (82.22%) with average root number per shoot of 6.72 ±0.48. The use of commercial sugar can effectively replace the use of expensive sucrose in in vitro multiplication of sugarcane varieties. All culture media were used in liquid state instead of semisolid agar media. Rooted shoots were transplanted in green house for hardening. Use of liquid media, chemical sterilant Sodium hypochlorite (NaOCl) and commercial sugar helped in reducing the cost per plantlet to a considerable extent.

Liquid vs Solid Culture Medium to Evaluate Proportion and Time to Change in Management of Suspects of Tuberculosis-A Pragmatic Randomized Trial in Secondary and Tertiary Health Care Units in Brazil.

BackgroundThe use of liquid medium (MGIT960) for tuberculosis (TB) diagnosis was recommended by WHO in 2007. However, there has been no evaluation of its effectiveness on clinically important outcomes.Methods and FindingsA pragmatic trial was carried out in a tertiary hospital and a secondary health care unit in Rio de Janeiro City, Brazil. Participants were 16 years or older, suspected of having TB. They were excluded if only cerebral spinal fluid or blood specimens were available for analysis. MGIT960 technique was compared with the Lowenstein-Jensen (LJ) method for laboratory diagnosis of active TB. Primary outcome was the proportion of patients who had their initial medical management changed within 2 months after randomisation. Secondary outcomes were: mean time for changing the procedure, patient satisfaction with the overall treatment and adverse events. Data were analysed by intention-to-treat. Between April 2008 and September 2011, 693 patients were enrolled (348 to MGIT, 345 to LJ). Smear and culture results were positive for 10% and 15.7% of participants, respectively. Patients in the MGIT arm had their initial medical management changed more frequently than those in the LJ group (10.1% MGIT vs 3.8% LJ, RR 2.67 95% CI 1.44–.96, p = 0.002, NNT 16, 95% CI 10–39). Mean time for changing the initial procedure was greater in LJ group at both sites: 20.0 and 29.6 days in MGIT group and 52.2 and 64.3 in LJ group (MD 33.5, 95% CI 30.6–36.4, p = 0.0001). No other important differences were observed.ConclusionsThis study suggests that opting for the MGIT960 system for TB diagnosis provides a promising case management model for improving the quality of care and control of TB.Trial RegistrationControlled-Trials.com ISRCTN79888843

Rapid multiplication of Dalbergia sissoo Roxb.: a timber yielding tree legume through axillary shoot proliferation and ex vitro rooting.

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 8.88μM 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 2.22μM of BAP and 0.002μM of thidiazuron (TDZ) with 1.0mM 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 984μM of indole-3-butyric acid (IBA) for 2min. About 90% microshoots were rooted on soilrite within 2-3weeks 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.

Photomixotrophic and photoautotrophic micropropagation ofStevia rebaudianaBertoni

The effect of different types of explants, PGRs, sucrose concentrations, different media and the strengths of medium were standardized to get the enhanced in vitro multiplication of Stevia rebaudiana. Efforts were also made to develop photoautotrophic micropropagation of Stevia. Among the various explants used for axillary bud induction the nodal explants showed the best results when cultured on 1x MS medium supplemented with 2.0 mM NAA+7.0 mM BAP or 5 mM IAA+7.0 mM BAP. Sucrose was proved as best carbon source at 3% concentration. The use of liquid medium did not affect the induction of buds but the elongation. BAP at 5 mM concentration was found best for further multiplication of shoots. Results pertaining to medium type and strength showed that MS medium at 1x strength alongwith 3% sucrose resulted in best multiplication and elongation of shoots. The in vitro raised Stevia plantlets were cultured on sugar free and sugar containing modified MS medium devoid of PGRs. Sugar containing medium proved better over sugar free medium.

Increasing Trend of Isolation of Non-Tuberculous Mycobacteria in a Tertiary University Hospital in South Korea

BackgroundThe isolation of non-tuberculous mycobacteria (NTM) has been increasing in South Korea. To date, however, the cause of this increase has not been determined, and it remains unclear whether the use of liquid media has contributed to this increase. The aim of this study was to evaluate the factors associated with NTM isolation and the impact of liquid media on NTM culture.MethodsMycobacterial smear/culture results of respiratory specimens (sputum and bronchial aspirates), obtained during the years 2002, 2005, and 2010, were retrieved and analyzed retrospectively.ResultsDuring the years 2002, 2005, and 2010, 83,096 sputum specimens were collected from 31,104 patients, and were cultured for mycobacteria, using solid media only in the 2002 and 2005 specimens and both solid and liquid media in the 2010. Of these, 3,516 (4.2%) specimens were smear-positive for acid-fast bacilli (AFB). The annual rate of NTM among positive culture specimens increased from 21% in 2002 to 57.8% in 2010 (p<0.001), as did the proportion of NTM, among AFB smear- and culture-positive specimens, from 12.2% in 2002 to 45.2% in 2010 (p<0.001). In 2010, the NTM culture rate was higher in the liquid than in the solid media (13.9% vs. 8.4%, p<0.001). The NTM rate among AFB-positive specimens was higher in patients aged >50 than ≤50 years.ConclusionThe rate of NTM isolation has steadily been increasing at the hospital in South Korea, likely due in part to the use of liquid media for the culture.

Improved Clonal Propagation of &amp;lt;i&amp;gt;Alpinia calcarata&amp;lt;/i&amp;gt; Rosc., a Commercially Important Medicinal Plant and Evaluation of Chemical Fidelity through Comparison of Volatile Compounds

An efficient and improved clonal propagation of Alpinia calcarata, a commercially important medicinal plant was established on Murashige and Skoog medium. The axillary shoot proliferation was achieved with maximum 5.2 ± 0.7 shoots in 92.8% of rhizome explants in medium with 2.0 mg/L 6-benzylamiopurine (BAP) and 0.2 mg/L indole-3-acetic acid (IAA). Axillary shoot buds (60%) upon subculture for 8 weeks in the same medium produced multiple shoot initials (12.1 ± 0.4) mediated with meristemoids (4.0 ± 0.5) and callus. A gradual reduction in the concentration of BAP or elimination of IAA was required for rapid induction of normal plants devoid of callus from propagules during subsequent subculture. Single clump of 3-4 multiple shoot initials during second subculture on medium with 1.0 mg/L BAP and 0.1 mg/L IAA yielded an average of 21 shoots which was best among different propagules tried. The shoot multiplication rate was further enhanced to 32 shoots when the similar propagules passed to third subculture on medium with 1.0 mg/L BAP alone. Clumps of multiple shoot initials upon subculture on medium with 1.0 mg/L BAP alone exhibited 10 fold multiplication rates. Use of liquid medium in culture bottles with polypropylene caps supported fast growth of the shoots and spontaneous root formation on 50% of the shoots. Shoots transferred to half-strength MS liquid medium with 0.2 mg/L of IAA and IBA was optimum for maximum roots (8.14 ± 1.34) in 100% shoots. The rooted plants were hardened in mist chamber showed 95% survival and well established in the field. The acclimatized plants showed rhizome formation after 4-6 weeks of growth under shade house. Volatile chemicals profile of the leaves, rhizome and root of the in vitro and conventionally propagated plants analyzed by gas chromatography-mass spectrometry were qualitatively and quantitatively similar. The analysis of growth characteristics of 36 month old in vitro and conventionally propagated plants showed a 50% increment of rhizome fresh biomass with prolific root and leaf growth in the former than the latter ones. The protocol described herein will have practical applications for the large scale production of uniform efficient plants for commercial cultivation of A. calcarata.

Diluição celular, características do meio de cultura e biorreatores de imersão temporária na diferenciação e regeneração de células em suspensão de bananeira

Altos custos de produção geralmente limitam o uso comercial da micropropagação. O uso de meios de cultura líquidos é considerado uma solução para a automação e redução de custos. Entretanto, dependendo da cultivar de bananeira, esse processo pode mostrar diferentes níveis de dificuldade, e adaptações nos protocolos são necessárias. Neste estudo, experimentos de diferenciação celular e regeneração de plantas foram desenvolvidos em células em suspensão de banana pela avaliação da densidade inicial de células, meios de cultura e sistemas de imersão temporária. Para tanto, uma sequência de três experimentos foi realizada: o primeiro avaliou os efeitos da densidade celular (0,5; 1 e 2 mL), meios de cultura (M1: 1/2MS, 0,1 g.L-1 de ácido ascórbico, 0,1 g.L-1 de L-prolina, 30 g.L-1 de sacarose e 10 µM de 2iP; M2: MS, 30 g.L-1 de sacarose, 2,2 µM de BAP e 11,4 µM de AIA) e períodos de diferenciação celular (40 e 130 dias); o segundo experimento analisou o efeito do tamanho dos propágulos diferenciados em meio líquido (aprox. 2,5; 5 e 10 mm em diâmetro) na formação de embriões somáticos ou na regeneração de plantas; finalmente, um terceiro experimento avaliou o efeito de sistemas de cultivo com papel-filtro cobrindo o meio de cultura semissólido e sistemas de imersão temporários na diferenciação dos propágulos e na regeneração de plantas. Não foram observadas diferenças significativas entre os meios de diferenciação, porém as melhores diluições de células para a diferenciação foram de 1 e 2 mL/30mL de meio de cultura, enquanto diluições de 0,5 mL/30 mL de meio aumentaram a oxidação celular. A extensão do período de diferenciação de 40 para 130 dias foi importante para produzir maior número de calos/propágulos uniformes e com pelo menos de 10 mm de diâmetro, que puderam ser usados em sistemas de imersão temporária (biorreatores) para a diferenciação de embriões somáticos e regeneração de plantas. Considerando todos os sistemas de regeneração, verificou-se que o uso de meios de regeneração de consistência semissólida com papel-filtro na superfície do meio é o mais responsivo para a diferenciação de embriões somáticos e regeneração de plantas.

Effect of phase of medium, growth regulators and nutrient supplementations on in vitro shoot-tip necrosis in pear

The incidence of shoot-tip necrosis (STN) was observed during the in vitro shoot multiplication and rooting stages of five Pyrus genotypes. During shoot multiplication, there was no incidence of STN in any of the five pear genotypes after 2 weeks of culture. However, after 6 weeks of culturing, necrotic apices were observed in all the pear genotypes, except wild pear. After 8 weeks of culture, 79.31% STN was observed in Punjab Beauty, followed by Patharnakh (49.60%), kainth (24.65%), shiara (17.68%) and wild pear (7.32%). Irrespective of the genotype, STN increased with an increase in BA concentration only in 8-week-old cultures. During in vitro rooting, the incidence of STN also varied with the genotype. In all five pear genotypes, the use of liquid media for in vitro rhizogenesis was useful in reducing the incidence of necrotic apices. The auxin type and level also influenced the occurrence of STN significantly. In wild pear, the incidence of necrotic apices increased with an increase in the concentration of auxins. A combination of Naphthalene acetic acid (NAA)+Indole-3-butyric acid (IBA) resulted in a higher incidence of STN than IBA or NAA alone at higher concentrations. Lower concentrations of IBA (0.62 to 2.46 µM L−1) resulted in a higher incidence of STN compared with the lower levels of NAA (0.67 and 1.34 µM L−1). In kainth, there was no significant difference in the incidence of STN at higher concentrations of IBA (5.37 and 10.74 µM L−1) and NAA (4.92 and 9.84 µM L−1). 2, 4-D resulted in a higher incidence of STN in comparison with IBA, NAA or NAA+IBA in the rooting medium. In Punjab Beauty, the percentage of necrotic apices at 0.67 and 1.34 µM L−1 NAA (40.46% and 40.04%, respectively) was on a par with the control (37.92%), but it was significantly less than the STN observed at 0.62 and 1.23 µM L−1 of IBA. In Patharnakh, IBA resulted in a significantly higher incidence of STN than NAA at all tested concentrations. In shiara, all the auxin treatments significantly increased STN. At lower levels (0.62 and 1.23 µM L−1), IBA resulted in a higher incidence of STN than the lower concentration of NAA (0.67 and 1.34 µM L−1), whereas at higher levels (2.46 to 9.84 µM L−1) IBA was on a par with NAA (2.69 to 10.74 µM L−1). Supplementation with calcium and boron significantly affected the percentage of necrotic apices in wild pear, Punjab Beauty and Patharnakh. In wild pear, raising the calcium level to 3 mM reduced the STN to 2.60%. In Punjab Beauty and Patharnakh, STN increased with an increase in calcium levels. Boron supplementations eliminated the incidence of STN in wild pear. Similarly, in Patharnakh, boron (500 µM and 1000 µM) significantly reduced the STN. Callus development was also observed at the base of pear shoots showing STN symptoms during rooting phase, but it did not show any significant trend. Higher levels of IBA, NAA+IBA and 2, 4-D resulted in the formation of large-sized calluses and STN in wild pear shoots on solid medium. There was a high incidence of STN in Punjab Beauty, Patharnakh and shiara but, the basal callus development in these genotypes was much less.