Triticale Isolated Microspore Culture for Doubled Haploid Production

Here, we describe a method of triticale isolated microspore culture for production of doubled haploid plants via androgenesis. We use this method routinely because it is highly efficient and works well on different triticale genotypes. To force microspores into becoming embryogenic, we apply a 21-day cold pretreatment. The shock of cold facilitates redirecting microspores from their predestined pollen developmental program into the androgenesis pathway. Ovaries are included in our culture methods to help with embryogenesis, and the histone deacytelase inhibitor Trichostatin A (TSA) is added to further improve androgenesis and increase our ability to recover green doubled haploid plants.

Optimization of an improved, efficient and rapid in vitro micropropagation protocol for Petunia hybrida Vilm. Cv. "Bravo"

An efficient protocol for in-vitro propagation of an important ornamental crop, Petunia hybrida Vilm. Cv. “Bravo” was developed. The explants that were used to carry out the experiment were Leaf segments, nodal segments and shoot tips. Nodal segments recorded highest per cent asepsis followed by shoot tips and leaf segments. Asepsis was found to be highest when the explants were sterilized with Fungicide (Carbendazim) 0.02% for the duration of 30 min followed by 0.1% HgCl₂ for duration of 10 min and then ethanol 70% for 10 s. Longer duration of the sterilant treatment showed more necrotic effects on the explants, thus mercuric chloride treatment when given for 5 min proved to be more effective in terms of survival of the explants. Maximum establishment per cent was recorded in Murashige and Skoog (MS) media fortified with BAP (1.5 mg L⁻¹) and IBA (0.5 mg L⁻¹) in shoot tips and nodal segments, i.e. 97.90 and 95.74% respectively. Callus was efficiently induced and developed when PGR amalgamation of BAP (0.1 mg L⁻¹) and 2,4-D (1.5mg L⁻¹) was used. Kinetin at the concentration of 2.0 mg L⁻¹ along with IBA at 0.5mg L⁻¹ recorded highest callus regeneration in both leaf and internodal segment derived callus. Maximum proliferation percent of shoots (97.90%), highest number of shoots (20.50 explant⁻¹) and maximum length of shoot (2.70 cm) was recorded in PGR combination of IBA and BAP both at 0.5 mg L⁻1 concentration level. Rhizogenesis was recorded to be highest in the MS media containing IBA 1.00 mg L⁻¹. Best hardening media which recorded maximum survival per cent 92.50% was noticed on the media formulation comprised of equal ratio of perlite and vermiculite mix, under poly house conditions.

An adventitious agent-free clonal cell line that is highly susceptible to foot -and-mouth disease virus

Porcine LFBKαVβ6 cells have been successfully used for diagnostics and propagation of all FMDV serotypes/subtypes. Unfortunately, after initial characterization, these cells showed contamination with bovine viral diarrhea virus (BVDV), a non-cytopathic adventitious agent. Persistent infection with BVDV could interfere with diagnostic tests and, also prevent consideration for other uses, i.e., vaccine production. In this study, we developed a three-prong methodology to completely remove BVDV from LFBKαVβ6 cells. Combined treatment with siRNA against BVDV NS5A, porcine interferon alpha and ribavirin resulted in the elimination of BVDV, as determined by immunohistochemistry analysis, quantitative RT-PCR and RNA sequencing. Importantly, elimination of BVDV from LFBKαVβ6 did not affect FMDV growth and plaque phenotype from different serotypes isolated and propagated in the clean cell line, newly named MGPK αVβ6-C5. Additionally, isolation of FMDV from field oro-pharyngeal samples, was successful at the same sensitivity as in BVDV-contaminated LFBKαVβ6 cells. Our results identified a direct method to efficiently eliminate BVDV from porcine cells without altering FMDV permissiveness, diagnostic value, or potential for use in vaccine production. Furthermore, these cells may provide an improved platform for diagnostics and propagation of other viruses of interest in the veterinary field and the virology community at large.

Ashwagandha: Advances in plant biotechnological approaches for propagation and production of bioactive compounds

ETHNOPHARMACOLOGICAL RELEVANCE

Withania somnifera is one of the most extensively delved Ayurvedic medicine. Apart from rejuvenation and increasing longevity, it has several other properties such as immunomodulation, anti-cancer, anti-stress and neuroprotection. Because of its prevailing use and increasing demand, it becomes prudent to scientifically evaluate and document both its propagation and production of desired phytoconstituents.

AIM OF THE STUDY

This review aims to highlight the research progress achieved on various biotechnological and tissue culture aspects of Withania somnifera and to cover up-to-date information regarding in-vitro propagation and production of withanolides.

MATERIALS AND METHODS

Significant published studies were identified for the years 2000-2018 using Elsevier-Science Direct, Pubmed and Google scholar and several research studies in our laboratory. Following keywords such as "plant extracts", "in vitro cultures", "callus and suspension culture", "micropropagation", "hairy root cultures" were used. Further, "Withania somnifera", "secondary metabolites specially withanolides", "molecular techniques" and "in vitro conservation" were used to cross-reference the keywords.

RESULTS

Ashwagandha comprises a broad spectrum of phytochemicals with a wide range of pharmacological properties. W. somnifera seeds have reduced viability and germination rates; thus, its regular cultivation method fails to achieve commercial demands mainly for the production of desired phytoconstituents. Cultivation of plant cells/tissues under in vitro conditions and development of various biotechnological strategies will help to build an attractive alternative to provide adequate quality and quantity raw materials. Recently, a large number of in vitro protocols has developed for W. somnifera not only for its propagation but for the production of secondary metabolites as well. Present work highlights a variety of biotechnological strategies both for prompt propagation and production of different bioactive secondary metabolites.

CONCLUSION

The present review focuses on the development and opportunities in various biotechnological approaches to accomplish the global demand of W. somnifera and its secondary metabolites. This review underlines the advances in plant biotechnological approaches for the propagation of W. somnifera and production of its bioactive compounds.

Bioproduction process of natural products and biopharmaceuticals: Biotechnological aspects

Decades of research have been put in place for developing sustainable routes of bioproduction of high commercial value natural products (NPs) on the global market. In the last few years alone, we have witnessed significant advances in the biotechnological production of NPs. The development of new methodologies has resulted in a better understanding of the metabolic flux within the organisms, which have driven manipulations to improve production of the target product. This was further realised due to the recent advances in the omics technologies such as genomics, transcriptomics, proteomics, metabolomics and secretomics, as well as systems and synthetic biology. Additionally, the combined application of novel engineering strategies has made possible avenues for enhancing the yield of these products in an efficient and economical way. Invention of high-throughput technologies such as next generation sequencing (NGS) and toolkits for genome editing Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated 9 (CRISPR/Cas9) have been the game changers and provided unprecedented opportunities to generate rationally designed synthetic circuits which can produce complex molecules. This review covers recent advances in the engineering of various hosts for the production of bioactive NPs and biopharmaceuticals. It also highlights general approaches and strategies to improve their biosynthesis with higher yields in a perspective of plants and microbes (bacteria, yeast and filamentous fungi). Although there are numerous reviews covering this topic on a selected species at a time, our approach herein is to give a comprehensive understanding about state-of-art technologies in different platforms of organisms.

A wake-like state in vitro induced by transmembrane TNF/soluble TNF receptor reverse signaling

Tumor necrosis factor alpha (TNF) has sleep regulatory and brain development roles. TNF promotes sleep in vivo and in vitro while TNF inhibition diminishes sleep. Transmembrane (tm) TNF and the tmTNF receptors (Rs), are cleaved by tumor necrosis factor alpha convertase to produce soluble (s) TNF and sTNFRs. Reverse signaling occurs in cells expressing tmTNF upon sTNFR binding. sTNFR administration in vivo inhibits sleep, thus we hypothesized that a wake-like state in vitro would be induced by sTNFR-tmTNF reverse signaling. Somatosensory cortical neuron/glia co-cultures derived from male and female mice lacking both TNFRs (TNFRKO), or lacking TNF (TNFKO) and wildtype (WT) mice were plated onto six-well multi-electrode arrays. Daily one-hour electrophysiological recordings were taken on culture days 4 through 14. sTNFR1 (0.0, 0.3, 3, 30, 60, and 120 ng/µL) was administered on day 14. A final one-hour recording was taken on day 15. Four measures were characterized that are also used to define sleep in vivo: action potentials (APs), burstiness index (BI), synchronization of electrical activity (SYN), and slow wave power (SWP; 0.25-3.75 Hz). Development rates of these emergent electrophysiological properties increased in cells from mice lacking TNF or both TNFRs compared to cells from WT mice. Decreased SWP, after the three lowest doses (0.3, 3 and 30 ng/µL) of the sTNFR1, indicate a wake-like state in cells from TNFRKO mice. A wake-like state was also induced after 3 ng/µl sTNFR1 treatment in cells from TNFKO mice, which express the TNFR1 ligand, lymphotoxin alpha. Cells from WT mice showed no treatment effects. Results are consistent with prior studies demonstrating involvement of TNF in brain development, TNF reverse signaling, and sleep regulation in vivo. Further, the current demonstration of sTNFR1 induction of a wake-like state in vitro is consistent with the idea that small neuronal/glial circuits manifest sleep- and wake-like states analogous to those occurring in vivo. Finally, that sTNF forward signaling enhances sleep while sTNFR1 reverse signaling enhances a wake-like state is consistent with other sTNF/tmTNF/sTNFR1 brain actions having opposing activities.

Modeling the mature CNS: A predictive screening platform for neurodegenerative disease drug discovery

Background:

Mature primary neuronal cultures are an important model of the nervous system, but limited scalability has been a major challenge in their use for drug discovery of neurodegenerative diseases. This work describes a method for improving scalability through the use of larger format microtiter plates while preserving culture quality.

New Method:

Here we describe a method and quality control procedures for growing embryonic day 18 rat hippocampal/cortical neuronal cultures in 384-well microtiter plates for three weeks in vitro.

Results:

We use these cultures in two assays measuring intracellular lipid vesicle trafficking and synapse density for routine screening of small molecule libraries. Together this culture system and screening platform have successfully identified therapeutics capable of improving cognitive function in transgenic models of Alzheimer’s disease that have advanced to clinical trials, validating their translational applicability.

Comparison with Existing Methods:

Our method enables the growth of healthy, mature neurons in larger format microtiter plates than in traditional primary neuronal culturing protocols, making it ideal for drug screening and mechanism of action studies.

Conclusion:

The predictive capacity of this culture system and screening platform provides a method for rapidly identifying novel disease-modifying neurodegenerative therapeutics.

Microbiological diagnosis of polymicrobial periprosthetic joint infection revealed superiority of investigated tissue samples compared to sonicate fluid generated from the implant surface

OBJECTIVES

In the microbiological diagnosis of periprosthetic joint infection (PJI), there is much discussion about the methodology of obtaining proper specimens, the processing technique, and suitable culture media. This retrospective study was conducted to analyse the accuracy of our culture techniques.

METHODS

Tissue samples and components from 258 patients after revision arthroplasty of the hip, knee, and shoulder were investigated, and the results of tissue cultures (TC) were compared to those of sonicate fluid cultures (SFC). Furthermore, an evaluation was performed of the influence of different culture media on the detection rate.

RESULTS

PJI was confirmed in 186 patients. The overall sensitivity of TC was no different to that of SFC (91.3% vs 90.8%, P = 1). In 153 cases (82.3%), TC and SFC showed concordant positive results. Results were discordant in 33 cases (17.7%). When differentiated according to the type of infection, TC showed significantly better results than SFC in detecting polymicrobial infections (97.0% vs 67.0%, P = 0.004). There were also significant differences between the culture media regarding the yield of microorganisms.

CONCLUSIONS

TC was more effective in detecting co-infections. The best results were obtained using both TC and SFC. The choice of culture media has a significant influence on the quality of results.

Sulfonated cryogel scaffolds for focal delivery in ex-vivo brain tissue cultures

The human brain has unique features that are difficult to study in animal models, including the mechanisms underlying neurodevelopmental and psychiatric disorders. Despite recent advances in human primary brain tissue culture systems, the use of these models to elucidate cellular disease mechanisms remains limited. A major reason for this is the lack of tools available to precisely manipulate a specific area of the tissue in a reproducible manner. Here we report an easy-to-use tool for site-specific manipulation of human brain tissue in culture. We show that line-shaped cryogel scaffolds synthesized with precise microscale dimensions allow the targeted delivery of a reagent to a specific region of human brain tissue in culture. 3-sulfopropyl acrylate (SPA) was incorporated into the cryogel network to yield a negative surface charge for the reversible binding of molecular cargo. The fluorescent dyes BODIPY and DiI were used as model cargos to show that placement of dye loaded scaffolds onto brain tissue in culture resulted in controlled delivery without a burst release, and labelling of specific regions without tissue damage. We further show that cryogels can deliver tetrodotoxin to tissue, inhibiting neuronal function in a reversible manner. The robust nature and precise dimensions of the cryogel resulted in a user-friendly and reproducible tool to manipulate primary human tissue cultures. These easy-to-use cryogels offer an innovate approach for more complex manipulations of ex-vivo tissue.

Datura genome reveals duplications of psychoactive alkaloid biosynthetic genes and high mutation rate following tissue culture

BACKGROUND

Datura stramonium (Jimsonweed) is a medicinally and pharmaceutically important plant in the nightshade family (Solanaceae) known for its production of various toxic, hallucinogenic, and therapeutic tropane alkaloids. Recently, we published a tissue-culture based transformation protocol for D. stramonium that enables more thorough functional genomics studies of this plant. However, the tissue culture process can lead to undesirable phenotypic and genomic consequences independent of the transgene used. Here, we have assembled and annotated a draft genome of D. stramonium with a focus on tropane alkaloid biosynthetic genes. We then use mRNA sequencing and genome resequencing of transformants to characterize changes following tissue culture.

RESULTS

Our draft assembly conforms to the expected 2 gigabasepair haploid genome size of this plant and achieved a BUSCO score of 94.7% complete, single-copy genes. The repetitive content of the genome is 61%, with Gypsy-type retrotransposons accounting for half of this. Our gene annotation estimates the number of protein-coding genes at 52,149 and shows evidence of duplications in two key alkaloid biosynthetic genes, tropinone reductase I and hyoscyamine 6 β-hydroxylase. Following tissue culture, we detected only 186 differentially expressed genes, but were unable to correlate these changes in expression with either polymorphisms from resequencing or positional effects of transposons.

CONCLUSIONS

We have assembled, annotated, and characterized the first draft genome for this important model plant species. Using this resource, we show duplications of genes leading to the synthesis of the medicinally important alkaloid, scopolamine. Our results also demonstrate that following tissue culture, mutation rates of transformed plants are quite high (1.16 × 10- 3 mutations per site), but do not have a drastic impact on gene expression.

A Plaque Reduction Neutralization Test for the Detection of ZIKV-Specific Antibodies

Neutralizing antibodies against Zika virus (ZIKV) are a robust indicator of exposure to ZIKV. Here we describe the plaque reduction neutralization test (PRNT), which quantifies ZIKV-neutralizing antibodies (nAbs) by incubating infectious ZIKV with different dilutions of sera and applying the mixture to a susceptible Vero cell monolayer. After 4 days of incubation, neutral red dye is added to optimize the visualization of plaques caused by ZIKV cytopathic effect. Compared with controls, sera containing nAbs against ZIKV will demonstrate ≥90% reduction in the number of plaques observed. This protocol can be utilized for research applications and serological diagnostic testing with the use of additional controls.

Imaging host-pathogen interactions using epithelial and bacterial cell infection models

The age-old saying, seeing is believing, could not be truer when we think about the value of imaging interactions between epithelial cells and bacterial pathogens. Imaging and culturing techniques have vastly improved over the years, and the breadth and depth of these methods is ever increasing. These technical advances have benefited researchers greatly; however, due to the large number of potential model systems and microscopy techniques to choose from, it can be overwhelming to select the most appropriate tools for your research question. This Review discusses a variety of available epithelial culturing methods and quality control experiments that can be performed, and outlines various options commonly used to fluorescently label bacterial and mammalian cell components. Both light- and electron-microscopy techniques are reviewed, with descriptions of both technical aspects and common applications. Several examples of imaging bacterial pathogens and their interactions with epithelial cells are discussed to provide researchers with an idea of the types of biological questions that can be successfully answered by using microscopy.

Anther Culture in Eggplant (Solanum melongena L.)

For a long time, conventional breeding methods have been used to obtain pure, 100% homozygous lines for hybrid seed production in crops of agronomic interest. However, by doubled haploid technology, it is possible to produce 100% homozygous plants derived from precursors of male gametophytes (androgenesis), to accelerate the production of pure lines, which implies important time and cost savings. In this chapter, a protocol for anther culture in eggplant is described, from donor plant growth conditions to regeneration and acclimation of doubled haploid plants, as well as a description of how to analyze ploidy levels of regenerated plants.

Detergent wash improves vaccinated lymph node handling ex vivo

Lymph nodes (LNs) are essential secondary immune organs where the adaptive immune response is generated against most infections and vaccines. We recently described the use of live ex vivo LN slices to study the dynamics of adaptive immunity. However, when working with reactive lymph nodes from vaccinated animals, the tissues frequently became dislodged from the supportive agarose matrix during slicing, leading to damage that prevented downstream analysis. Because reactive lymph nodes expand into the surrounding adipose tissue, we hypothesized that dislodging was a result of excess lipids on the collagen capsule of the LN, and that a brief wash with a mild detergent would improve LN interaction with the agarose without damaging tissue viability or function. Therefore, we tested the use of digitonin on improving slicing of vaccinated LNs. Prior to embedding, LNs were quickly dipped into a digitonin solution and washed in saline. Lipid droplets were visibly removed by this procedure. A digitonin wash step prior to slicing significantly reduced the loss of LN during slicing from 13 to 75% to 0-25%, without substantial impact on viability. Capture of fluorescent microparticles, uptake and processing of protein antigen, and cytokine secretion in response to a vaccine adjuvant, R848, were all unaffected by the detergent wash. This novel approach will enable ex vivo analysis of the generation of adaptive immune response in LNs in response to vaccinations and other immunotherapies.

Cell membrane rupture: a novel test reveals significant variations among different brands of tissue culture flasks

Objectives

Loss of cytoplasmic molecules including protein controls, due to cell membrane rupture can cause errors and irreproducibility in research data. Previous results have shown that during the washing of a monolayer of cells with a balanced salt solution, the fluid force causes cell membrane rupture on some areas of the flasks/dishes. This fact shows the non-uniformity of the polystyrene surface in terms of cell culture. There is at present no simple test to monitor that surface. This paper presents a novel biologically based assay to determine the degree of heterogeneity of flasks supplied by various manufacturers.

Results

This paper shows that significant variation exists in polystyrene surface heterogeneity among several brands of tissue culture flasks, varying from 4 to 20% of the flask surface. There is also large variability within the production lot of a manufacturer. The assay method involves loading the cells with a cytoplasmic fluorescent marker that is released upon cell membrane rupture. Cell membrane rupture also causes the loss of marker proteins such as GAPDH used in Westernblots. This novel assay method can be used to monitor the batch consistency and the manufacturing process of flasks/dishes. It may also be used to test new biomaterials.

Description of Cohnella zeiphila sp. nov., a bacterium isolated from maize callus cultures

A Gram-stain positive, aerobic, motile, rod-shaped bacterium designated as strain CBP-2801^T was isolated as a contaminant from a culture containing maize callus in Peoria, Illinois, United States. The strain is unique relative to other Cohnella species due to its slow growth and reduced number of sole carbon sources. Phylogenetic analysis using 16S rRNA indicated that strain CBP-2801^T is a Cohnella bacterium and showed the highest similarity to Cohnella xylanilytica (96.8%). Genome-based phylogeny and genomic comparisons based on average nucleotide identity confirmed the strain to be a novel species of Cohnella. Growth occurs at 15-45 °C (optimum 40 °C), pH 5-7 (optimum pH 6) and with 0-1% NaCl. The predominant fatty acids are anteiso-15:0 and 18:1 ω6c. Genome mining for secondary metabolites identified a putative biosynthetic cluster that encodes for a novel lasso peptide. In addition, this study contributes five new genome assemblies of type strains of Cohnella species, a genus with less than 30% of the type strains sequenced. The DNA G + C content is 58.7 mol %. Based on the phenotypic, phylogenetic and biochemical data strain CBP-2801^T represents a novel species, for which the name Cohnella zeiphila sp. nov. is proposed. The type strain is CBP-2801^T (= DSM 111598 = ATCC TSD-230).

Generation of Mouse Eosinophils in Tissue Culture from Unselected Bone Marrow Progenitors

Human eosinophilic leukocytes are found in peripheral blood and tissues at homeostasis and at elevated levels in atopic disorders. As inbred strains of mice (Mus musculus) are currently the models of choice for the study of disease mechanisms in vivo, a full understanding of mouse eosinophils is critical for interpretation of experimental findings. Toward this end, several years ago we presented a protocol for generating mouse eosinophils in tissue culture from unselected bone marrow progenitors (Dyer et al., J Immunol 181: 4004-4009, 2008). This method has been implemented widely and has proven to be effective for generating phenotypically normal eosinophils from numerous mouse strains and genotypes. Here we provide a detailed version of this protocol, along with suggestions and notes for its careful execution. We have also included several protocol variations and suggestions for improvements.

Cryopreservation of Plant Shoot Tips of Potato, Mint, Garlic, and Shallot Using Plant Vitrification Solution 3

Cryopreservation of shoot tips facilitates long-term storage of plant genetic resources which can otherwise only be propagated vegetatively. The vitrification approach using the cryoprotectant plant vitrification solution 3 (PVS3, 50% sucrose and 50% glycerol) is easy to handle, has shown to produce high regrowth percentages in a number of potato, mint, garlic, and shallot accessions, and is, thus, highly suitable for routine cryopreservation of plant genetic resources. In the current chapter, the vitrification procedure is described for potato, mint, garlic, and shallot and includes details about modifications for the different plant species. Special emphasis is given on the preparation of the different culture media, solutions, the culture conditions prior and post-cryopreservation, and the preparation of the shoot tips from different sources. Furthermore, protocols to introduce plants into in vitro culture and methods to estimate cryopreservation success are provided.

Overview of In Vitro and In Vivo Doubled Haploid Technologies

Doubled haploids (DH) have become a powerful tool to assist in different basic research studies, and also in applied research. The principal (but not the only) and routine use of DH by breeding companies is to produce pure lines for hybrid seed production in different crop species. Several decades after the discovery of haploid inducer lines in maize and of anther culture as a method to produce haploid plants from pollen precursors, the biotechnological revolution of the last decades allowed to the development of a variety of approaches to pursue the goal of doubled haploid production. Now, it is possible to produce haploids and DHs in many different species, because when a method does not work properly, there are several others to test. In this chapter, we overview the currently available approaches used to produce haploids and DHs by using methods based on in vitro culture, or involving the in vivo induction of haploid embryo development, or a combination of both.

Transformation of the Plastid Genome in Tobacco Suspension Cell Cultures

Chloroplast transformation has been extremely valuable for the study of plastid biology and gene expression, but the tissue culture methodology involved can be laborious and it can take several months to obtain homoplasmic regenerated plants useful for molecular or physiological studies. In contrast, transformation of tobacco suspension cell plastids provides an easy and efficient system to rapidly evaluate the efficacy of multiple constructs prior to plant regeneration. Suspension cell cultures can be initiated from many cell types, and once established, can be maintained by subculture for more than a year with no loss of transformation efficiency. Using antibiotic selection, homoplasmy is readily achieved in uniform cell colonies useful for comparative gene expression analyses, with the added flexibility to subsequently regenerate plants for in planta studies. Plastids from suspension cells grown in the dark are similar in size and cellular morphology to those in embryogenic culture systems of monocot species, thus providing a useful model for understanding the steps leading to plastid transformation in those recalcitrant species.

Variability of seizure-like activity in an in vitro model of epilepsy depends on the electrical recording method

Background

Hippocampal and cortical slice-based models are widely used to study seizures and epilepsy. Seizure detection and quantification are essential components for studying mechanisms of epilepsy and assessing therapeutic interventions. To obtain meaningful signals and maximize experimental throughput, variability should be minimized. Some electrical recording methods require insertion of an electrode into neuronal tissue, change in slice chemical microenvironment, and transients in temperature and pH. These perturbations can cause acute and long-term alterations of the neuronal network which may be reflected in the variability of the recorded signal.

New method

In this study we investigated the effect of experimental perturbations in three local field potential (LFP) recording methods including substrate micro-wires (s-MWs), multiple electrode arrays (MEAs), and inserted micro wire electrodes (i-MW). These methods enabled us to isolate effects of different perturbations. We used organotypic hippocampal slices (OHCs) as an in-vitro model of posttraumatic epilepsy. To investigate the effect of the disturbances caused by the recording method on the paroxysmal events, we introduced jitter analysis, which is sensitive to small differences in the seizure spike timing.

Results

Medium replacement can introduce long-lasting perturbations. Electrode insertion increased variability on a shorter time scale. OHCs also underwent spontaneous state transitions characterized by transient increases in variability.

Comparison with existing methods

This new method of seizure waveform analysis allows for more sensitive assessment of variability of ictal events than simply measuring seizure frequency and duration.

Conclusion

We demonstrated that some of the variability in OHC recordings are due to experimental perturbations while some are spontaneous and independent of recording method.

Nexus between light and culture media on morphogenesis in Bacopa monnieri and saponin yield thereof

Bacopa monnieri, a well-documented nootropic plant of high commercial global demand had been explored for its effect in alleviating other diseases and symptoms. This is primarily attributed to different phytocompounds present in the plant. One of the major constituents among them are saponins. However, variation in agro-climatic conditions and choice of germplasm often affect the growth rate and yield of phytocompounds that significantly impact the efficacy of the plant and its extract. Tissue culture has been attempted to improve the yield of phytocompounds but is often restricted by higher cost and scalability. Current study explores the role of commercial hydroponic media ‘Leafy 200’ vis-à-vis Murashige and Skoog (MS) media, under different color and intensity of lights, on plant morphogenesis, biomass and saponin yield. Blue light induced more shoot differentiation than normal white light. Statistical studies performed using fractional factorial design showed no significant variations in the yield of saponins among the extracts. The study suggests that hydroponic culture to be a sustainable solution and possible substitute to tissue culture that may be exploited for scalable cultivation of the plant.

Experimental design of a culture approach for corneal endothelial cells of New Zealand white rabbit

The harvesting of corneal endothelial cells (CEC) has received special attention due to its potential as a therapy for corneal blindness. The main challenges are related to the culture media formulation, cellular density at the primary isolation, and the number of passages in which CEC can retain their functional characteristics. To alternate different media formulations to harvest CEC has an impact on the cellular yield and morphology. Therefore, we analyzed four different sequences of growth factor-supplemented Stimulatory (S) and non-supplemented Quiescent (Q) media, upon passages to find the optimal S-Q culture sequence. We assessed cell yield, morphology, procollagen I production, Na⁺/K⁺-ATPase function, and the expression of ZO-1 and Na⁺/K⁺-ATPase. Our results show SQSQ and SQQQ sequences with a balance between an improved cell yield and hexagonal morphology rate. CEC cultured in the SQQQ sequence produced procollagen I, showed Na⁺/K⁺-ATPase function, and expression of ZO-1 and Na⁺/K⁺-ATPase. Our study sets a culture approach to guarantee CEC expansion, as well as functionality for their potential use in tissue engineering and in vivo analyses. Thus, the alternation of S and Q media improves CEC culture. SQQQ sequence demonstrated CEC proliferation and lower the cost implied in SQSQ sequences. We discarded the use of pituitary extract and ROCK inhibitors as essential for CEC proliferation.

Effects of Kiss2 on the Expression of Gonadotropin Genes in the Pituitary of Nile Tilapia (Oreochromis niloticus)

Kisspeptin, expressed mainly in the hypothalamus, stimulates gonadotropin-releasing hormone neurons to facilitate reproduction. In some model animals, the kisspeptin is also expressed in the pituitary. Recently, a pathway has been suggested in which kisspeptin acts directly on the pituitary to secretion of gonadotropin in mammals. In the present study, pituitaries of the Nile tilapia (Oreochromis niloticus) were cultured at different concentrations of kisspeptin-10 (Kp-10, FNYNPLSLRF) for 3 hours to observe the effect of kisspeptin on the expression of follicle-stimulating hormone β subunit (fshβ) gene and luteinizing hormone β subunit (lhβ) gene. Pituitary tissues were cultured with 0.1 μM of Kp-10, luteinizing hormone releasing hormone (LHRH), or LHRH+Kp-10 for 3, 6, 12, and 24 hours to investigate changes in the expression of fshβ and lhβ mRNA. Pituitaries cultured with high concentration of Kp-10 more than 0.1 μM for 3 hours exhibited a significant increase of fshβ mRNA expression, but not lhβ mRNA. The expression of both fshβ and lhβ mRNA increased after 6 hours in 0.1 μM of Kp-10 medium in comparison with that in the control medium. Tissues cultured in the LHRH medium however exhibited increased expression of both genes not only at 6 but also 12 hours. There were no significant differences of fshβ and lhβ gene expression in tissues cultured with LHRH+KP-10 medium compared with the control. These results suggested that although kisspeptin plays an important role in fshβ and lhβ expression in the pituitary of Nile tilapia, its action is far more complicated than expected.

Influence of colorful light-emitting diodes on growth, biochemistry, and production of volatile organic compounds in vitro of Lippia filifolia (Verbenaceae)

Lippia filifolia Mart. & Schauer belongs to the Verbenaceae family and it is endemic from the rupestrian fields of the Espinhaço mountain range, located in Minas Gerais, Brazil. It is an aromatic species with medicinal potential due to the production of volatile compounds that constitute its essential oil. The objective of this work was to evaluate the effects of light quality using light-emitting diodes (LEDs) over the growth of L. filifolia grown in vitro after 45 days of culture, analyzing its volatile organic compounds (VOCs), biochemical, and biometric traits. This study had four treatments according to the wavelength of LED lamps: (i) white (control), (ii) blue, (iii) red, and (iv) a combination of red + blue (mix). The light quality influenced the growth, metabolism, and VOCs production of plantlets. The specimens showed higher height under red and white treatments and higher biomass accumulation, nodal segments, and shoot numbers under the mix treatment. Higher total carbohydrate content was also observed on the mix treatment, while the white LED provided higher chlorophylls and carotenoids contents. In addition, the lipid peroxidation was more pronounced in mix and white LEDs treatments, and it was also observed significant but not quite changes in VOCs profiles due to light quality. Eucalyptol was the compound found in a higher concentration among the VOCs of L. filifolia grown in vitro at all light quality treatments studied.

Diagnostic concordance of clinical diagnosis, tissue culture, and histopathology testing for skin and soft tissue infections: A single-center retrospective study

Background

Tissue culture and histopathology are the conventional diagnostic modalities for skin and soft tissue infections (SSTIs), but few studies have investigated their concordance.

Objective

Determine concordance between histopathology and tissue culture in the diagnosis of suspected SSTIs.

Methods

Single-center retrospective study of 355 cases with suspected SSTIs identified from the dermatology inpatient consultation log January 2014-July 2017.

Results

Overall concordance between histopathology testing and tissue culture results was high (76.1%). Concordance was high for cases defined as no evidence of infection, fungal infection and mycobacterial infection by histopathology (77.8%, 74.2%, and 80.0%) and tissue culture (92.1%, 67.7%, and 83.3%). Concordance was lower for suspected SSTIs with bacterial infection by histopathology (61.9%) and tissue culture (28.4%). Concordance rates were not significantly affected by age, sex, race, antimicrobial agent use, immunologic status, or biopsy size.

Limitations

Retrospective and single-institution nature of the study.

Conclusion

This study demonstrated a high concordance between histopathology and tissue culture in SSTIs with no clinical evidence of infection and suspected fungal and mycobacterial SSTIs, though concordance was lower for suspected SSTIs with evidence of bacterial infection. Clinicians should not be deterred from relying on initial histopathological results based on patients' immunosuppressed status, antimicrobial agent use, age, or biopsy tissue size.

Production of ascorbic acid, total protein, callus and root in vitro of non-heading Chinese cabbage by tissue culture

The objective of the present work was the selection of cultivar, suitable medium and explant type for callus, root production, ascorbic acid, total ascorbic acid, dehydroascorbic and total protein of non-heading Chinese cabbage in two cultivars 'Caixin' and 'Suzhouqing'. We compared 10 types of MS media supplemented with 0.0, 1.0, 2.0 and 3.0 mg/l TDZ; 0.0, 0.25, 0.50 and 1.0 mg/l NAA and 0.0, 5.0, 7.5 and 9.0 mg/l AgNO₃ and 5 kinds of explants as embryo, leaf, root, cotyledon and hypocotyl. Maximum frequency of callus fresh weight was recorded with hypocotyl explant, which were cultured on MS + 2.0 mg/l TDZ + 1.0 mg/l NAA + 9.0 mg/l AgNO₃ in 'Suzhouqing', optimum callus dry weight was obtained on the same media. The highest result for root fresh and dry weight recorded with 'Caixin' with MS + 3.0 mg/l TDZ + 1.0 mg/l NAA + 9.0 mg/l AgNO₃ when we used embryo as explant. The highest ascorbic acid content was found with callus cultured on MS + 1.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO₃, when used leaf explant in 'Caixin' or root in 'Suzhouqing', and there were no significant difference between them. While the highest value of total AsA content was registered with callus cultured on MS + 2.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO₃ extracted from cotyledon in 'Caixin'. The highest content of DHA was registered with MS + 2.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO₃ with cotyledon in 'Caixin'. Also, in 'Caixin' MS + 3.0 mg/l TDZ + 0.25 mg/l NAA + 5.0 mg/l AgNO₃ recorded the highest value of total protein content with embryo explant.

Efficient direct shoot organogenesis and genetic stability in micropropagated sacha inchi (Plukenetia volubilis L.)

OBJECTIVE

It is necessary to improve biotech platforms based on in vitro cell tissue culture to support sacha inchi (Plukenetia volubilis L.) research programs and draw on the nutritional value of the high polyunsaturated fatty acid content of its oilseed. Here, we developed a rapid and efficient method for induction and direct in vitro shoot development for this species.

RESULTS

Shoots were generated from hypocotyl explants. The highest organogenic response was obtained in woody plant medium supplemented with 1 mg/L thidiazuron and 0.5 mg/L zeatin supplemented with L-glutamine, adenine hemisulfate, and L-arginine. Shoots obtained using this medium were transferred and subcultivated with different concentrations of indole-3-butyric acid and 1-naphthylacetic acid for rooting. For the first time, a histological analysis was performed supporting direct organogenic development in this species. The plantlets obtained were transferred ex vitro with a survival percentage of 80%. The genetic stability of the plants recovered was confirmed by randomly amplified polymorphic DNA analysis. All results indicate that it would be possible to stimulate direct shoot formation from hypocotyls to support the sustainable use of this species.

The effect of PEGylated iron oxide nanoparticles on sheep ovarian tissue: An ex-vivo nanosafety study

Today, nanotechnology plays an important role in our ever-continuous quest to improve the quality of human life. Because of their infinitesimal size, nanostructures can actively interact and alter cellular functions. Therefore, while the clinical benefits of nanotechnology may outweigh most of the associated risks, assessment of the cytotoxicity of nanostructures in respect to cells and tissues early in product development processes is of great significance. To the best of our knowledge, no such assessment has been performed for nanomaterials on the ovarian cortex before. Herein, silica-coated, PEGylated silica-coated, and uncoated iron oxide nanoparticles (IONP) with core diameter of 11 nm (±4.2 nm) were synthesized. The oxidative stress in cultured ovarian tissue exposed to the various IONP was subsequently assessed. The results indicate that among the four groups, uncoated IONP induce the most oxidative stress on the ovarian cortex while tissues treated with PEGylated IONP exhibit no significant change in oxidative stress.

Induced in vitro adaptation for salt tolerance in date palm (Phoenix dactylifera L.) cultivar Khalas

BACKGROUND

Soil salinity causes huge economic losses to agriculture productivity in arid and semiarid areas worldwide. The affected plants face disturbances in osmotic adjustment, nutrient transport, ionic toxicity and reduced photosynthesis. Conventional breeding approaches produce little success in combating various stresses in plants. However, non-conventional approaches, such as in vitro tissue culturing, produce genetic variability in the development of salt-tolerant plants, particularly in woody trees.

RESULTS

Embryogenic callus cultures of the date palm cultivar Khalas were subjected to various salt levels ranging from 0 to 300 mM in eight subcultures. The regenerants obtained from the salt-treated cultures were regenerated and evaluated using the same concentration of NaCl with which the calli were treated. All the salt-adapted (SA) regenerants showed improved growth characteristics, physiological performance, ion concentrations and K+/Na+ ratios than the salt non-adapted (SNA) regenerants and the control. Regression between the leaf Na+ concentration and net photosynthesis revealed an inverse nonlinear correlation in the SNA regenerants. Leaf K+ contents and stomatal conductance showed a strong linear relationship in SA regenerants compared with the inverse linear correlation, and a very poor coefficient of determination in SNA regenerants. The genetic fidelity of the selected SA regenerants was also tested using 36 random amplified polymorphic DNA (RAPD) primers, of which 26 produced scorable bands. The primers generated 1-10 bands, with an average of 5.4 bands per RAPD primer; there was no variation between SA regenerants and the negative control.

CONCLUSION

This is the first report of the variants generated from salt-stressed cultures and their potential adaptation to salinity in date palm cv. Khalas. The massive production of salt stress-adapted date palm plants may be much easier using the salt adaptation approach. Such plants can perform better during exposure to salt stress compared to the non-treated date palm plants.

Microbiological diagnosis of intramedullary nailing infection: comparison of bacterial growth between tissue sampling and sonication fluid cultures

BACKGROUND

Intramedullary nailing (IMN) has been frequently indicated to treat long bone open and closed fractures, but IMN infection (IMNI) may have devastating consequences. Sonication has been regarded as an important add-on for microbial identification on a variety of orthopaedic implant-associated infections, but its role in the IMNI is poorly studied. We aim at evaluating the accuracy obtained by conventional peri-implant tissue culture (TC) samples with sonication fluid cultures (SCs) of IMNI.

METHODS

Longitudinal prospective cohort study ongoing since June 2014, which included patients with indication for IMN removal due to any reason. Clinical diagnosis of INMI was defined according to publication addressing fracture-related infections. Minimal of two samples from TC were cultured. SCs followed the protocol previously published. Statistical analysis was performed using McNemar's test for related proportions.

RESULTS

We included 54 patients submitted to IMN retrieval, of whom 47 presenting clinical signs of IMNI. Sensitivity for detecting microorganisms using TC and SC was 89.4% (42/47) and 97.6% (40/41), and specificity was 71.4% (5/7) for both TC and SC (p = 1.00). Positive and negative predictive values for TC and SC were 95.5% (42/44), 95.2% (40/42), 50% (5/10), and 83.3% (5/6), respectively. The most frequent organisms isolated in both TC and SC were Staphylococcus aureus, S. epidermidis, and Enterococcus sp. Polymicrobial infection was diagnosed in 14.8% (8/54) and 25% (12/48) by TC and SC, respectively (p = 0.19).

CONCLUSION

Sonication fluid and tissue samples presented similar accuracy on the diagnosis of IMNI, but SC was advantageous of detecting polymicrobial infection.

Culture of human ovarian tissue in xeno-free conditions using laminin components of the human ovarian extracellular matrix

PURPOSE

Our purpose was to identify human ovarian extracellular matrix (ECM) components that would support in vitro culture of human ovarian tissue and be compatible with possible future clinical applications. We characterized ovarian expression of laminins and selected three laminin tripeptides for culture experiments to be compared with Matrigel, an undefined and animal-based mixture of ECM components.

METHODS

Expression of the 12 laminin genes was determined on transcript and protein levels using cortical tissue samples (n = 6), commercial ovary RNA (n = 1), follicular fluid granulosa cells (n = 20), and single-cell RNA-sequencing data. Laminin 221 (LN221), LN521, LN511, and their mixture were chosen for a 7-day culture experiment along with Matrigel using tissue from 17 patients. At the end of the culture, follicles were evaluated by scoring and counting from serial tissue sections, apoptosis measured using in situ TUNEL assay, proliferation by Ki67 staining, and endocrine function by quantifying steroids in culture media using UPLC-MS/MS.

RESULTS

Approximately half of the cells in ovarian cortex expressed at least one laminin gene. The overall most expressed laminin α-chains were LAMA2 and LAMA5, β-chains LAMB1 and LAMB2, and γ-chain LAMC1. In culture experiments, LN221 enhanced follicular survival compared with Matrigel (p < 0.001), whereas tissue cultured on LN521 had higher proportion of secondary follicles (p < 0.001). LN511 and mixture of laminins did not support the cultures leading to lower follicle densities and higher apoptosis. All cultures produced steroids and contained proliferating cells.

CONCLUSIONS

LN221 and LN521 show promise in providing xeno-free growth substrates for human ovarian tissue cultures, which may help in further development of folliculogenesis in vitro for clinical practices. The system could also be used for identification of adverse effects of chemicals in ovaries.

The regeneration of Acer rubrum L. "October Glory" through embryonic callus

BACKGROUND

Tissue culture and rapid propagation technology is an important way to solve the difficulties of plant propagation. This experiment aims to explore the appropriate conditions at each stage of the red maple's tissue culture process and to obtain plantlets, thus providing a theoretical basis for the establishment of the red maple's tissue culture system.

RESULTS

The results showed that the stem segment is the most suitable explant for inducing embryogenic callus. The MS (Murashige&Skoog) + 0.8 mg/L TDZ (Thidiazuron) + 1.0 mg/L 6-BA (6-Benzylaminopurine) + 0.5 mg/L IAA(Indole-3-acetic acid) + 35 g/L sucrose+ 7.5 g/L semi-fixed medium was the best for callus formation. When selecting type VI callus as embryonic callus induction material, MS + 0.6 mg/L TDZ + 0.5 mg/L 6-BA + 2.0 mg/L IAA + 35 g/L sucrose+ 7.5 g/L semi-fixed medium can get embryonic callus. The optimal medium for adventitious bud induction is MS + 1.0 mg/L TDZ + 3.0 mg/L 6-BA+ 0.2 mg/L NAA (1-Naphthaleneacetic acid) + 1.2 mg/L IAA + 35 g/L sucrose+ 7.5 g/L semi-fixed medium. The induction rate of adventitious roots in MS + 0.6 mg/L TDZ + 1.0 mg/L 6-BA+ 3 mg/L NAA + 35 g/L sucrose+ 7.5 g/L semi-fixed medium was the highest, reaching 76%.

CONCLUSIONS

In the course of our research, we found that PGRs play an important role in the callus induction stage, and the effect of TDZ is particularly obvious; The callus cells grow and proliferate according to the "S" growth curve, and can be sub-cultured when the highest growth point is reached to maintain the rapid proliferation of the callus cells and to avoid inactivation of callus caused by tight niche.

Short-term neuronal effects of fumonisin B1 on neuronal activity in rodents

Fumonisin B1 (FB1) is a mycotoxin produced by microscopic fungi (mostly Fusarium species), which may infect our major crops. The toxin inhibits the development of these plants and may also have harmful effects on animals and humans consuming the infected crops. FB1 inhibits sphingolipid biosynthesis which leads to altered membrane characteristics and consequently, altered cellular functions. There are some indications that the toxin has inhibitory effects on neuronal activity in case of repeated consumption, presumably due to sphingolipid depletion. However, according to new literature data, FB1 may have acute excitatory neural effects, too, via different mechanisms of action. Therefore, in the present study, we addressed the neuronal network effects of FB1 following acute treatment, using different electrophysiological techniques in vitro and in vivo. Acute treatments with FB1 (10-100 μM) were carried out on brain slices, tissue cultures and live animals. After direct treatment of samples, electrically evoked or spontaneous field potentials were examined in the hippocampus and the neocortex of rat brain slices and in hippocampal cell cultures. In the hippocampus, a short-term increase in the excitability of neuronal networks and individual cells was observed in response to FB1 treatment. In some cases, the initially enhanced excitation was reversed presumably due to overactivation of neuronal networks. Normal spontaneous activity was found to be stimulated in hippocampal cell cultures. Seizure susceptibility was not affected in the neocortex of brain slices. For the verification of the results caused by direct treatment, effects of systemic administration of FB1 (7.5 mg/kg, i.p.) were also examined. Evoked field potentials recorded in vivo from the somatosensory cortex and cell activation measured by the c-fos technique in hippocampus and somatosensory cortex were analyzed. However, the hippocampal and cortical stimulatory effect detected in vitro could not be demonstrated by these in vivo assays. Altogether, the toxin enhanced the basic excitability of neurons and neuronal networks after direct treatment but there were no effects on the given brain areas after systemic treatment in vivo. Based on the observed in vitro FB1 effects and the lack of data on the penetration of FB1 across the blood-brain barrier, we assume that in vivo consequences of FB1 administration can be more prominent in case of perturbed blood-brain barrier functions.

Relevance of humanized three-dimensional tumor tissue models: a descriptive systematic literature review

Despite numerous advances in tumor screening, diagnosis, and treatment, to date, tumors remain one of the leading causes of death, principally due to metastasis and the physiological damage produced by tumor growth. Among the main limits related to the study of tumor physiology there is the complex and heterogeneity nature of its environment and the absence of relevant, simple and inexpensive models able to mimic the biological processes occurring in patients allowing the correct clinical translation of results. To enhance the understanding of the mechanisms of tumors and to develop and evaluate new therapeutic approaches the set-up of advanced and alternative models is mandatory. One of the more translational approaches seems to be the use of humanized three-dimensional (3D) tissue culture. This model allows to accurately mimic tumor morphology and biology, maintaining the native microenvironment without any manipulation. However, little is still known on the real clinical relevance of these models for the study of tumor mechanisms and for the screening of new therapy. The aim of this descriptive systematic literature review was to evaluate and summarize the current knowledge on human 3D tumor tissue culture models. We reviewed the strategies employed by researchers to set-up these systems, also considering the different approaches and culture conditions used. All these aspects greatly contribute to the existing knowledge on tumors, providing a specific link to clinical scenarios and making the humanized 3D tumor tissue models a more attractive tool both for researchers and clinicians.

Transcriptome sequencing and identification of key callus browning-related genes from petiole callus of tree peony (Paeonia suffruticosa cv. Kao) cultured on media with three browning inhibitors

Tree peony (Paeonia suffruticosa Andrews) has ornamental, oil, and medicinal values, and demand in the markets for uniform tree peony seedlings is increasing. Micropropagation could quickly propagate uniform seedlings. However, the heavy browning phenomenon hinders large-scale development of uniform tree peony seedlings. In this paper, we measured the total phenolic compounds content, and sequenced the transcriptomes of tree peony 'Kao' petiole calluses cultured on media with three browning antagonist treatments and fresh petioles to identify the key genes involved in callus browning. Polyvinylpyrrolidone (PVP) treatment can reduce production of phenolic compounds and promote callus regeneration. A total of 218,957 unigenes were obtained from fresh petiole and three kinds of browning petiole calluses by transcriptome sequencing. The average sequence length of unigenes was 446 bp with an N50 of 493 bp. Functional annotation analysis revealed that 43,428, 45,357, 31,194, 30,019, and 21,357 unigenes were annotated using the NCBI-NR database, Swiss-Prot, KOG, GO, and KEGG, respectively. In total, 33 differentially expressed genes (DEGs) were identified as potentially associated with callus browning. Among these DEGs, 12 genes were predicted to participate in phenolic compounds biosynthesis, three genes were predicted to be involved in phenolic compounds oxidation, and six genes were predicted to participate in callus regeneration. Moreover, six transcription factors were observed to be differentially expressed in the fresh petiole and three treated petioles in tree peony. This study comprehensively identifies browning-related gene resources and will possibly help in deciphering the molecular mechanisms of callus browning of tree peony in the future.

Sonication in shoulder surgery: is it necessary?

PURPOSE

The objective of the present study was to determine whether sonication yields greater sensitivity when compared with the traditional tissue culture in detecting peri-implant infections in shoulder surgery.

METHODS

It is a retrospective study that includes 99 shoulder surgeries with implants explanted. The inclusion criteria required at least four tissue cultures, sonication of the material explanted, and a minimum follow-up of two years. Patients were classified according to the definition of periprosthetic shoulder infection of the 2018 International Consensus Meeting on Orthopedic Infections. The classifications are definitive infection, probable infection, possible infection, and unlikely infection.

RESULTS

Among the 99 surgical procedures, 31 were considered definitive infections, 11 possible/probable infections, and 57 unlikely infections. Considering the cases with a definitive infection, the sensitivity of the tissue culture was 87.09% and the sensitivity of sonication stood at 80.64% (p = 0.406). Analyzing the cases with a definitive infection and those having a possible/probable infection together and comparing them with those with unlikely infection, the sensitivity of sonication was 80.4% and the sensitivity of the tissue culture came to 91.4%. The specificity of the sonication was 98.1% and the specificity of the tissue culture was 99.6%.

CONCLUSION

The sensitivity of sonication in shoulder surgery (80.64%) is not superior to the sensitivity of the tissue culture (87.09%). Specificity remains high with both methods, being 98.1% in the sonication group and 99.6% in the tissue culture. Sonication brings no benefit to the detection of shoulder per-implant infections.

Enhancement of phenolic content, antioxidant and cytotoxic activities of Moringa oleifera leaf and seed by suspension culture

Moringa oleifera Lam. family Moringaceae is well known for a wide range of biological activities and a complex phytochemical composition. The current study investigates tissue culture protocols for Moringa oleifera leaves and seeds. For static culture initiation, Murashige and skooge (MS) as a basal medium with hormonal supply of (0-10 µM) of 2,4-dicholorophenoxy acetic acid and 6-benzyl aminopurine for Moringa oleifera seeds and leaves was employed. Suspension cultures with the optimum hormonal combination was initiated for both seeds and leaves calli. Liquid chromatography/mass spectroscopy (LC/MS) analysis performed, for the first time, on the methanolic extracts of plant parts and the produced calli revealed varying concentrations of nine major components (six flavonoids and three phenolic acids). Antioxidant and cytotoxic activities, against three cell lines, were evaluated for the obtained methanolic extracts. In general, superior biological activities were identified for the produced calli when compared to plant parts.

Don

BACKGROUND

Fritillaria cirrhosa, an important Chinese medicinal herb, is a Class-III protected and highly exploited species by pharmaceutical industry. Dwindling wild populations of species are unable to meet market demand. Therefore, this study was carried out to develop an in vitro propagation method for bulblet production. Also, the study aimed to carry out LC-MS/MS analysis of tissue culture-derived bulblets and callus for the presence of isosteroidal alkaloids (peimissine, verticine, and verticinone), and compare its quantities with commercially available crude drug samples.

RESULTS

In vitro seed germination (91%) of F. cirrhosa was achieved on Murashige and Skoog's basal medium (MSBM) supplemented with 6-benzylaminopurine (1 mg L^-1) and α-naphthalene-acetic-acid (0.4 mg L^-1). On transfer of germinated seeds from Petri-dishes to glass bottles containing hormone-free MSBM, 37.5% of seedlings developed bulblets after 3 months of incubation. Regeneration and multiplication of bulblets were achieved by culture of transverse sections of bulblets on 1/2 X MSBM. By repeated subcultures at an interval of 2 months, 3072 bulblets weighing 1270 g could be produced at the end of 5th subculture. LC-MS/MS analysis showed a significant presence of peimissine in in vitro bulblets while callus incubated in the dark showed presence of peimissine and verticine.

CONCLUSION

The study reports an efficient in vitro propagation method of bulblets production of F. cirrhosa and presence of some isosteroidal alkaloids in tissue culture-derived bulblets and callus. The study could be of immense help in production of F. cirrhosa bulblets and callus under laboratory conditions round the year. Also, these results can be used further to investigate production of isosteroidal alkaloids in bioreactors at commercial scale using liquid and cell suspension cultures. Thus, we not only can reduce our dependence on collections from natural habitats, but also can help in in situ conservation of this important species.

Synergistic Effect of NaCl Pretreatment and PVP on Browning Suppression and Callus Induction from Petal Explants of Paeonia Lactiflora Pall. 'Festival Maxima'

Browning is prevalent in tissue cultures of Paeonia lactiflora Pall. (herbaceous peony), and severely affects and restricts the growth and differentiation of the explants. In this study, dipping excised explants in a sodium chloride (NaCl) solution as a pretreatment, adding polyvinyl pyrrolidone (PVP) to the culture medium, storing planted explants at 4 °C for 24 h, and transferring planted explants to a new medium after 24 h were considered as browning-suppression methods in tissue cultures of herbaceous peony 'Festival Maxima'. The treated petal explants were cultured in a culture room with a 16-hour photoperiod, 25 °C temperature, and 80% relative humidity in darkness for 4 to 8 weeks. The results demonstrated that dipping excised explants in a 0.5 g·L-1 NaCl solution, adding 0.5 g·L-1 PVP to the medium, storing planted explants at 4 °C for 24 h, and transferring planted explants to the same fresh medium after 24 h could effectively inhibit browning. Adding PVP to the medium led to the greatest browning suppression percentage of 95%. Storing planted explants at 4 °C for 24 h reduced the effectiveness of other treatments in suppressing browning. After 8 weeks, dipping excised explants in a NaCl solution resulted in the highest callus induction percentage of 75%, while storing explants at 4 °C for 24 h suppressed callus formation. It was observed in all treatments that decreases in browning was accompanied with higher levels of phenols and lower activities of phenylalanine ammonia-lyase (PAL) and polyphenoloxidase (PPO). Overall, the results suggest that dipping in a NaCl solution was effective in alleviating the browning issues of herbaceous peony tissue cultures, and had positive synergistic effects with PVP on browning suppression and callus induction.

Engraftment potential of maternal adipose-derived stem cells for fetal transplantation

Advances in prenatal molecular testing have made it possible to diagnose most genetic disorders early in gestation. In utero mesenchymal stem cell (MSC) therapy can be a powerful tool to cure the incurable. With this in mind, this method could ameliorate potential physical and functional damage. However, the presence of maternal T cells trafficking in the fetus during pregnancy is thought to be the major barrier to achieving the engraftment into the fetus. We investigated the possibility of using maternal adipose-derived stem cells (ADSCs) for in utero transplantation to improve engraftment, thus lowering the risk of graft rejection. Herein, fetal brain engraftment using congenic and maternal ADSC grafts was examined via in utero stem cell transplantation in a mouse model. ADSCs were purified using the mesenchymal stem cell markers, PDGFRα, and Sca-1 via fluorescence-activated cell sorting. The PDGFRα⁺Sca-1⁺ ADSCs were transplanted into the fetal intracerebroventricular (ICV) at E14.5. The transplanted grafts grew for at least 28 days after in utero transplantation with PDGFRα⁺Sca-1⁺ ADSC, and mature neuronal markers were also detected in the grafts. Furthermore, using the maternal sorted ADSCs suppressed the innate immune response, preventing the infiltration of CD8 T cells into the graft. Thus, in utero transplantation into the fetal ICV with the maternal PDGFRα⁺Sca-1⁺ ADSCs may be beneficial for the treatment of congenital neurological diseases because of the ability to reduce the responses after in utero stem cell transplantation and differentiate into neuronal lineages.

Skull diploë is rich in aquaporin-4

Aquaporin-4 (AQP4) is a water conducting membrane integral protein channel which is widely expressed in the astrocyte system of the brain. During the development of the AQP4 positron emission tomography (PET) imaging agent [¹¹C]TGN-020 (N-(1,3,4-thiadiazol-2-yl)pyridine-3-[¹¹C]-carboxamide), significant radioligand uptake was observed in the skull, where there was no known distribution of any aquaporin family proteins. Herein we confirmed via a newly developed method for bone-tissue immunohistology, a hitherto unrecognized distribution of AQP4, and not AQP1, in the skull. Other bony structures, by contrast, showed virtually no uptake of [¹¹C]TGN-020, and likewise, do not express either AQP4 or AQP1. Immunohistological analysis demonstrated that the AQP4 expression in the skull is restricted to the diploë. Consequently, we suspect AQP4 plays a pivotal role in the formation and maintenance of yellow marrow and the diploë. However, elucidating the exact nature of that role will require further studies.

Cryopreservation of shoot apices and callus cultures of globe artichoke using vitrification method

Background

Cryogenic cooling became a crucial tool for the storage of heterozygous plants such as globe artichoke. This study was carried out to optimize a reliable method for in vitro cryopreservation of shoot apices and callus cultures of globe artichoke using dimethylsulfoxide (DMSO) and Plant Vitrification Solutions 2 (PVS2) as cryoprotectant solutions. Shoot apices were exposed to DMSO or PVS2 for 20, 40, 60, and 80 min prior to plunge in liquid nitrogen (LN).

Results

It was found that using PVS2 as a cryoprotectant in cryopreservation of shoot apices of globe artichoke was more effective compared with using of DMSO alone. Among the exposure time tested, 60 min gave the best results of survival. The highest survival (60%), regeneration (56%), and proliferated shootlets (4.30) were obtained after cryoprotection with PVS2 for 60 min. Regarding callus cultures, the maximum values of fresh weights and subsequently growth value of recovered callus were registered with 40 min followed by 60 min exposure time. Related to the type of the tested cryoprotectants, the best survival and growth parameters of the cryopreserved callus cultures were obtained with PVS2 treatments. Treatment with PVS2 for 40 min registered the highest survival observations of cryopreserved callus. Also, the maximum values of fresh weight (1.30 g) and growth value (4.20) were obtained with 40 min exposure time. Microscopy analysis presented as cell morphology revealed that the treatment of PVS2 40% was the optimum for cell growth of cryopreserved callus of globe artichoke.

Conclusion

The results demonstrated that using PVS2 as a cryoprotectant in cryopreservation of shoot apices and callus cultures of globe artichoke was more effective compared with DMSO.

HSV Mutant Generation and Dual Detection Methods for Gaining Insight into Latent/Lytic Cycles In Vivo

Two important components of a useful strategy to examine viral gene function, regulation, and pathogenesis in vivo are (1) a highly efficient protocol to generate viral mutants that limits undesired mutation and retains full replication competency in vivo, and (2) an efficient system to detect and quantify viral promoter activity and gene expression in rare cells in vivo and to gain insight into the surrounding tissue environment. Our strategy and protocols for generating, characterizing, and employing HSV viral promoter/reporter mutants in vivo are provided in this two-part chapter.

Genetic Transformation of Common Wheat (Triticum aestivum L.) Using Biolistics

The following protocol describes the genetic transformation of wheat using the BioRad PDS/1000-He particle delivery system. Immature embryos are isolated 12-16 days post-anthesis, the embryonic axis is removed, and the immature scutella are precultured for 1-2 days prior to particle bombardment. Gold particles are coated with plasmid DNA containing the gene(s) of interest plus a selectable marker gene, in this instance bar (bialaphos resistance), and are fired into the cells to deliver the DNA. Subsequent tissue culture and regeneration steps allow recovery of plantlets, assisted by the inclusion of PPT (phosphinothricin tripeptide), the active ingredient of glufosinate-ammonium containing herbicides, to help select transformants. This updated method introduces selection earlier in the regeneration process which provides a shortened protocol while maintaining high transformation efficiencies.

CRISPR/Cas9-Based Gene Editing in Soybean

CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat/CRISPR associated Cas9)-based gene editing is a robust tool for functional genomics research and breeding programs in various crops. In soybean, a number of laboratories have obtained mutants by CRISPR/Cas9 system; however, there has been not yet a detailed method for the CRISPR/Cas9-based gene editing in soybean. Here, we describe the procedures for constructing the CRISPR/Cas9 plasmid suitable for soybean gene editing and the modified protocols for Agrobacterium-mediated soybean transformation and regeneration from cotyledonary node explants containing the Cas9/sgRNA (single guide RNA) transgenes.

Isolated Microspore Culture in Brassica napus

Isolated microspore culture is the most efficient technique among those used to induce microspore embryogenesis. In the particular case of Brassica napus, it is also the most widely used and optimized. In this chapter, we describe a protocol for microspore culture in B. napus which includes the steps necessary to isolate and culture microspores, to induce microspore-derived embryos, to produce doubled haploid plants from them, as well as to check for the developmental stage of the microspores isolated, their viability, and the ploidy level of regenerated plantlets.

Antioxidant response to cadmium exposure in primary skeletal muscle cells isolated from humans and elephant seals

Cadmium (Cd) occurs naturally; however, its concentration can increase with anthropogenic activities. Excess Cd increases reactive oxygen species (ROS) production and oxidative damage, which can lead to pathological conditions. Marine mammals accumulate Cd in the liver and the kidney; yet, there are no reports of Cd-associated tissue damage in whales, seals or dolphins. Response to Cd exposure (0-5.0 μM CdCl₂ for 1-12 h) was analyzed and compared in primary skeletal muscle cells isolated from northern elephant seals (Mirounga angustirostris) and humans (Homo sapiens). Antioxidant enzyme activities (glutathione S-transferase, glutathione reductase, glutathione peroxidase), glutathione concentration, and protein carbonyl levels (an indicator of oxidative damage) were quantified. Glutathione levels were higher in northern elephant seal than in human cells. Protein carbonyl content in cells exposed to Cd was lower and had a smaller variability range in elephant seals than in humans. Generalized linear models (GLIM) identified Cd exposure and antioxidant defenses as significant contributors to protein carbonyl variability in human but not in elephant seal cells. These results suggest that the previously observed differences in circulating and tissue glutathione levels between marine and terrestrial mammals are maintained under cell culture conditions and that northern elephant seal and human muscle cells respond differently to Cd exposure. The results also suggest that the observed differences could potentially be associated with the protective mechanisms that allow northern elephant seals to tolerate extreme conditions that result in increased ROS generation (e.g. diving, sleep apnea, fasting) with no oxidative damage.

Choice of Explant for Plant Genetic Transformation

Particle bombardment or biolistic transformation is an efficient, versatile method. This method does not need any vector for the gene transfer and is not dependent on the cell type, species, and genotype. The success of any transformation technique depends on the starting experimental materials or the explants. Here, we describe the factors that have influenced the choice of explants in biolistic transformation. Many general factors in the selection of explants in the development of transgenic plants are presented here. Therefore, this chapter provides extensive guidelines regarding the choice of explants for researchers working on various plant genetic transformation techniques.

From cells highly tolerant to Zn and Pb to fully fertile plants - Selection of tolerant lines with in vitro culture

Viola arvensis cells were selected after treatment with Zn or Pb and regenerated into plants likely to have higher tolerance levels than the initial plant. The surviving cells in the suspension treated with 2000 μM of Zn, 2000 μM of Pb or 0 μM for 72 h were maintained on a solidified half-strength MS medium supplemented with 0.5 mg L^-1 TDZ to induce divisions and organogenesis. The adventitious shoots obtained were rooted on a half-strength MS medium with 1 mg L^-1 IBA. Regenerants derived from the Zn- and Pb-treated cells were vigorous and fully fertile. The in vitro conditions and metal impact generated a low genome alteration and overall low genetic diversity of regenerants compared to the initial plant and plants from the natural population. The cells of regenerants obtained after Pb treatment represented an approximately 12% higher tolerance level to Pb than the cells of the initial plant. This is the first report of plant regeneration from highly tolerant cells selected by heavy metal treatment. Regenerants successfully obtained in vitro could be considered as a source material for the recultivation of areas polluted with heavy metals.