Probing the Phytochemical Composition and Antioxidant Activity of Moringa oleifera under Ideal Germination Conditions

Moringa oleifera is a rich source of polyphenols whose contents and profile may vary according to environmental conditions, harvest season, and plant tissue. The present study aimed to characterize the profile of phenolic compounds in different tissues of M. oleifera grown under different temperatures (25, 30, and 35 °C), using HPLC/MS, as well as their constituent phytochemicals and in vitro antioxidant activities. The in vitro antioxidant activity of the extracts was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylenebenzothiozoline-6-sulfonicacid (ABTS), and ferric-reducing antioxidant power (FRAP) methods. The polyphenolic compounds were mainly found in the leaves at 30 °C. UPLC/QTOF-MS allowed for the identification of 34 polyphenolic components in seedlings, primarily consisting of glucosides, phenols, flavonoids, and methoxy flavones. At 30 °C, the specific activities of antioxidative enzymes were the highest in leaves, followed by seedlings and then seeds. The leaf and seed extracts also exhibited a greater accumulation of proline, glycine betaine, and antioxidants, such as ascorbic acid, and carotenoids, as measured by the inhibition of ROS production. We found that changes in the expression levels of the validated candidate genes Cu/Zn-SOD, APX, GPP, and TPS lead to significant differences in the germination rate and biochemical changes. These findings demonstrate that M. oleifera plants have high concentrations of phytochemicals and antioxidants, making them an excellent choice for further research to determine their use as health-promoting dietary supplements.

Comparative seed cryopreservation of indonesian and new zealand epiphytic and terrestrial orchids

BACKGROUND

The atypical seed storage behaviour reported in several orchid species justifies cryopreservation as a complementary conservation strategy to conventional seed banking.

OBJECTIVE

This study aimed to assess the seed cryopreservation potential of five orchid species; two tropical epiphytic, Indonesian species (Dendrobium strebloceras, D. lineale), one temperate epiphytic, New Zealand species (D. cunninghamii) and two temperate terrestrial, New Zealand species (Pterostylis banksii, Thelymitra nervosa).

MATERIALS AND METHODS

Seeds were cryopreserved by direct immersion in liquid nitrogen (LN) and through the application of a cryoprotectant vitrification method. For the latter, seeds were exposed to Plant Vitrification Solution 2 (PVS2) for 0, 20, 50, and 70 min, at either room temperature or on ice, prior to immersion in LN.

RESULTS

Seeds of all the studied species germinated well following direct cooling in LN. There was no difference in the seedling development capability between cryopreserved and non-cryopreserved seeds of both tropical epiphytic species and direct immersion in LN enhanced seed germination and shoot formation in both temperate terrestrials.

CONCLUSION

Through a range of analyses of germination and post-germination growth, our study shows the potential for cryopreserving epiphytic or terrestrial orchids from tropical and temperate regions. Doi: 10.54680/fr23410110312.

Phenological phase affects carrot seed production sensitivity to climate change - A panel data analysis

New Zealand is a major producer of carrot seeds globally. Carrots are an important nutritional crop for human consumption. Since the growth and development of carrot seed crops mainly depend on climatic factors, seed yield is extremely susceptible to climate change. This modeling study was undertaken using a panel data approach to determine the impact of the atmospheric conditions (proxied by maximum and minimum temperature) and precipitation during the critical growth stages for seed production in carrot, viz., juvenile phase, vernalization phase, floral development phase, and flowering and seed development phase on carrot seed yield. The panel dataset was created using cross-sections from 28 locations within the Canterbury and Hawke's Bay regions of New Zealand that cultivate carrot seed crops and time series from 2005 to 2022. Pre-diagnostic tests were performed to test the model assumptions, and a fixed effect model was selected subsequently. There was significant (p < 0.01) variability in temperature and rainfall throughout different growing phases, except for precipitation at the vernalization phase. The highest rate of changes in maximum temperature, minimum temperature, and precipitation were recorded during the vernalization phase (+0.254 °C per year), floral development phase (+0.18 °C per year), and juvenile phase (-6.508 mm per year), respectively. Based on marginal effect analysis, the highest significant influence of minimum (187.724 kg/ha of seed yield decrease for each 1 °C increment) and maximum temperature (1 °C rise increases seed yield by 132.728 kg/ha), and precipitation (1 mm increment of rainfall decreases the seed yield by 1.745 kg/ha) on carrot seed yield were reported at vernalization, and flowering and seed development, respectively. The minimum and maximum temperatures have a higher marginal effect on carrot seed production. Analysis of the panel data demonstrates that the production of carrot seeds will be vulnerable to climatic change.

A-27 Stakeholder Attitudes and Perceptions regarding Concussion in Athletes with Intellectual Disabilities

Purpose: Sports-related concussion (SRC) is a public health concern with particular complexities that occur in Special Olympics (SO) because injuries and acute identification tools are not well understood for athletes with intellectual disabilities (ID). The purpose of this study was to explore current education, recognition and management strategies among coaches and caregivers in Special Olympics North America (SONA). Methods: A descriptive survey via the Qualtrics platform was distributed to coaches and caregivers in SONA through their electronic newsletter. Analyses included descriptive statistics and Chi square frequencies. Results: Out of a total 103 returned surveys, 77 were fully completed by coaches (83%) and caregivers (17%) from 10 states. The majority of coaches (91%) completed concussion education within the last two years. Sixty-one percent of coaches reported coaching a contact or high concussion-risk sport; moreover, these coaches were more likely to recognize injuries (p = 0.02). Forty-three percent of coaches disclosed that concussions may be underreported in SO, but 72.5% agreed that concussion are serious injuries. Although coaches generally felt prepared to recognize (95%) and remove (95%) athletes with SRC symptoms, management strategies to recognize (34%) or treat (39%) SRC athletes with ID was low. Coaches described feeling less confident to manage these return-to-play decisions following injury (76%). Non-healthcare professionals were first responders for injuries during non-competition (68%) events and competition (14%). Conclusions: Coaches involved in SO should complete tailored concussion education training to enhance recognition and management strategies. Future initiatives should target curriculum adapted to communication needs of athletes with ID.

Seed viability and fatty acid profiles of five orchid species before and after ageing

Changes in seed lipid composition during ageing are associated with seed viability loss in many plant species. However, due to their small seed size, this has not been previously explored in orchids. We characterized and compared the seed viability and fatty acid profiles of five orchid species before and after ageing: one tropical epiphytic orchid from Indonesia (Dendrobium strebloceras), and four temperate species from New Zealand, D. cunninghamii (epiphytic), and Gastrodia cunninghamii, Pterostylis banksii and Thelymitra nervosa (terrestrial). Seeds were aged under controlled laboratory conditions (3-month storage at 60% RH and 20 °C). Seed viability was tested before and after ageing using tetrazolium chloride staining. Fatty acid methyl esters from fresh and aged seeds were extracted through trans-esterification, and then analysed using gas chromatography-mass spectrometry. All species had high initial viability (>80%) and experienced significant viability loss after ageing. The saturated, polyunsaturated, monounsaturated and total fatty acid content decreased with ageing in all species, but this reduction was only significant for D. strebloceras, D. cunninghamii and G. cunninghamii. Our results suggest that fatty acid degradation is a typical response to ageing in orchids, albeit with species variation in magnitude, but the link between fatty acid degradation and viability was not elucidated. Pterostylis banksii exemplified this variation; it showed marked viability loss despite not having a significant reduction in its fatty acid content after ageing. More research is required to identify the effect of ageing on fatty acid composition in orchids, and its contribution to seed viability loss.

Methylobacterium, a major component of the culturable bacterial endophyte community of wild Brassica seed

BACKGROUND

Plants are commonly colonized by a wide diversity of microbial species and the relationships created can range from mutualistic through to parasitic. Microorganisms that typically form symptomless associations with internal plant tissues are termed endophytes. Endophytes associate with most plant species found in natural and managed ecosystems. They are extremely important plant partners that provide improved stress tolerance to the host compared with plants that lack this symbiosis. Plant domestication has reduced endophyte diversity and therefore the wild relatives of many crop species remain untapped reservoirs of beneficial microbes. Brassica species display immense diversity and consequently provide the greatest assortment of products used by humans from a single plant genus important for agriculture, horticulture, bioremediation, medicine, soil conditioners, composting crops, and in the production of edible and industrial oils. Many endophytes are horizontally transmitted, but some can colonize the plant's reproductive tissues, and this gives these symbionts an efficient mechanism of propagation via plant seed (termed vertical transmission).

METHODS

This study surveyed 83 wild and landrace Brassica accessions composed of 14 different species with a worldwide distribution for seed-originating bacterial endophytes. Seed was stringently disinfected, sown within sterile tissue culture pots within a sterile environment and incubated. After approximately 1-month, direct isolation techniques were used to recover bacterial endophytes from roots and shoots of symptomless plants. Bacteria were identified based on the PCR amplification of partial 16S rDNA gene sequences and annotated using the BLASTn program against the NCBI rRNA database. A diversity index was used as a quantitative measure to reflect how many different bacterial species there were in the seed-originating microbial community of the Brassica accessions sampled.

RESULTS

Bacterial endophytes were recovered from the majority of the Brassica accessions screened. 16S rDNA gene sequencing identified 19 different bacterial species belonging to three phyla, namely Actinobacteria, Firmicutes and Proteobacteria with the most frequently isolated species being Methylobacterium fujisawaense, Stenotrophomonas rhizophila and Pseudomonas lactis. Methylobacterium was the dominant genus composing 56% of the culturable isolated bacterial community and was common in 77% of accessions possessing culturable bacterial endophytes. Two selected isolates of Methylobacterium significantly promoted plant growth when inoculated into a cultivar of oilseed rape and inhibited the growth of the pathogen Leptosphaeria maculans in dual culture. This is the first report that investigates the seed-originating endophytic microorganisms of wild Brassica species and highlights the Brassica microbiome as a resource for plant growth promoting bacteria and biological control agents.

Comparative Seed Morphology of Tropical and Temperate Orchid Species with Different Growth Habits

Seed morphology underpins many critical biological and ecological processes, such as seed dormancy and germination, dispersal, and persistence. It is also a valuable taxonomic trait that can provide information about plant evolution and adaptations to different ecological niches. This study characterised and compared various seed morphological traits, i.e., seed and pod shape, seed colour and size, embryo size, and air volume for six orchid species; and explored whether taxonomy, biogeographical origin, or growth habit are important determinants of seed morphology. We investigated this on two tropical epiphytic orchid species from Indonesia (Dendrobium strebloceras and D. lineale), and four temperate species from New Zealand, terrestrial Gastrodia cunnninghamii, Pterostylis banksii and Thelymitra nervosa, and epiphytic D. cunninghamii. Our results show some similarities among related species in their pod shape and colour, and seed colouration. All the species studied have scobiform or fusiform seeds and prolate-spheroid embryos. Specifically, D. strebloceras, G. cunninghamii, and P. banksii have an elongated seed shape, while T. nervosa has truncated seeds. Interestingly, we observed high variability in the micro-morphological seed characteristics of these orchid species, unrelated to their taxonomy, biogeographical origin, or growth habit, suggesting different ecological adaptations possibly reflecting their modes of dispersal.

The effects of salinity and osmotic stress on barley germination rate: sodium as an osmotic regulator

BACKGROUND AND AIMS

Seed germination is negatively affected by salinity, which is thought to be due to both osmotic and ion-toxicity effects. We hypothesize that salt is absorbed by seeds, allowing them to generate additional osmotic potential, and to germinate in conditions under which they would otherwise not be able to germinate.

METHODS

Seeds of barley, Hordeum vulgare, were germinated in the presence of either pure water or one of five iso-osmotic solutions of polyethylene-glycol (PEG) or NaCl at 5, 12, 20 or 27 °C. Germination time courses were recorded and germination indices were calculated. Dry mass, water content and sodium concentration of germinating and non-germinating seeds in the NaCl treatments at 12 °C were measured. Fifty supplemental seeds were used to evaluate the changes in seed properties with time.

KEY RESULTS

Seeds incubated in saline conditions were able to germinate at lower osmotic potentials than those incubated in iso-osmotic PEG solutions and generally germinated faster. A positive correlation existed between external salinity and seed salt content in the saline-incubated seeds. Water content and sodium concentration increased with time for seeds incubated in NaCl. At higher temperatures, germination percentage and dry mass decreased whereas germination index and sodium concentration increased.

CONCLUSIONS

The results suggest that barley seeds can take up sodium, allowing them to generate additional osmotic potential, absorb more water and germinate more rapidly in environments of lower water potential. This may have ecological implications, allowing halophytic species and varieties to out-compete glycophytes in saline soils.

A psoralen-conjugated triplex-forming oligodeoxyribonucleotide containing alternating methylphosphonate-phosphodiester linkages: synthesis and interactions with DNA

A psoralen-conjugated oligodeoxyribopyrimidine (1443), PS-pTTTTCTTTTCTTCTT, where PS is trimethylpsoralen and C is 5-methyl-2'-deoxycytidine, that contains alternating methylphosphonate-phosphodiester internucleotide linkages was synthesized. The ability of 1443 to form triple-stranded complexes with a purine tract in a synthetic DNA duplex was studied. Irradiation of solutions containing the DNA target and 10 microM 1443 or 0.25 microM of a similar psoralen-conjugated oligodeoxyribonucleotide that contained all phosphodiester linkages, (1193), with long-wavelength UV light resulted in approximately 80% formation of interstrand cross-links at pH 7.0, 37 degrees C, in the presence of 20 mM magnesium chloride. The extent of triplex formation as monitored by photo-cross-linking decreased over the pH range 5.5-8.0, and the apparent pK of the 5-methylcytosines (C) in 1443 was approximately one-half of a pH unit less than that of the 5-methylcytosines in 1193. Oligomer 1443 formed triplexes in the absence of magnesium, and maximum triplex formation was observed in solutions containing 2.5 mM magnesium, whereas maximal triplex formation by the fully charged 1193 was not observed until the magnesium concentration was 10 mM or higher. Unlike the all-phosphodiester backbone of 1193, the alternating methylphosphonate-phosphodiester backbone of 1193 is resistant to hydrolysis by exonucleases in fetal calf serum. The nuclease resistance of 1443 and its ability to form triplexes at very low magnesium concentrations suggests that triplex-forming oligomers with alternating methylphosphonate-phosphodiester backbones may be good candidates for use as antigene reagents in cell culture.

Pediatric intestinal leiomyosarcomas: case report and review of the literature

Primary intestinal leiomyosarcomas in children are rare tumors. Twenty-seven previous cases are documented in the literature with little information available on the treatment, survival, and prognostic factors surrounding these tumors. The authors report the 28th case of pediatric intestinal leiomyosarcoma and its follow-up, that of a newborn presenting with intestinal obstruction. Follow-up from all previously reported cases is not recorded and is needed. Our patient, like most children with this tumor, underwent complete excision with no evidence of recurrence at 5 years. Visceral metastases from these neoplasms are atypical, and recorded long-term prognosis may be favorable, unlike their counterpart in the adult population.

Ends-in vs. ends-out recombination in yeast

Integration of linearized plasmids into yeast chromosomes has been used as a model system for the study of recombination initiated by double-strand breaks. The linearized plasmid DNA recombines efficiently into sequences homologous to the ends of the DNA. This efficient recombination occurs both for the configuration in which the break is in a contiguous region of homology (herein called the ends-in configuration) and for "omega" insertions in which plasmid sequences interrupt a linear region of homology (herein called the ends-out configuration). The requirements for integration of these two configurations are expected to be different. We compared these two processes in a yeast strain containing an ends-in target and an ends-out target for the same cut plasmid. Recovery of ends-in events exceeds ends-out events by two- to threefold. Possible causes for the origin of this small bias are discussed. The lack of an extreme difference in frequency implies that cooperativity between the two ends does not contribute to the efficiency with which cut circular plasmids are integrated. This may also be true for the repair of chromosomal double-strand breaks.

Aortogastric fistula: a complication of tube gastrostomy

This is a report of a patient who developed a previously undescribed gastrostomy tube complication, namely, fatal aortogastric fistula.

Coconversion of flanking sequences with homothallic switching

Homothallic switching in S. cerevisiae involves replacing the DNA of the expressed allele at the mating type locus (MAT) with a duplicate of sequences from the unexpressed loci HML or HMR. The MATa and MAT alpha alleles differ by a DNA substitution that is flanked by sequences in common to MAT, and the donor loci HML and HMR. Using restriction site polymorphisms between MAT and the donor loci, we demonstrate that the extent of MAT DNA that is replaced during switching is variable and that there is a gradient of coconversion across the X region. Coconversion events occur on both sides of the double-strand cleavage by the HO gene product. The two cells produced after a switch often differ at the flanking site, indicating a DNA heteroduplex intermediate.

a/Alpha-specific repression by MAT alpha 2

The product of the MAT alpha 2 gene is a DNA-binding protein that acts as a repressor of two different sets of cell type-specific genes. In alpha cells, the alpha 2 protein represses the transcription of several a-specific genes. In a/alpha cells, the alpha 2 protein acts together with the product of the MATa1 gene, the a1 protein, to repress several genes used by haploids in the mating process. In addition to the mat alpha 2 mutations that result in defects in both types of regulation, other mat alpha 2 alleles have been described that result in defects in the repression of a-specific genes but that do not affect the ability of the alpha 2 and a1 proteins to interact to repress the haploid-specific genes. We report here the isolation of a new class of mat alpha 2 mutations that do not affect the ability of the alpha 2 protein to repress a-specific genes, but that interfere with the ability of the alpha 2 protein to interact with the a1 protein to repress the haploid-specific genes and establish the a/alpha cell type. These mutations may help determine the means by which the a1 protein interacts with alpha 2 to expand the set of genes under its control.

Expression of soluble, enzymatically active, human immunodeficiency virus reverse transcriptase in Escherichia coli and analysis of mutants

We have constructed a plasmid that, when introduced into Escherichia coli, induces the synthesis of large quantities of a protein with an apparent molecular mass of 66 kDa that differs from human immunodeficiency virus (HIV) RNA-dependent DNA polymerase (deoxynucleoside-triphosphate:DNA deoxynucleotidyltransferase or reverse transcriptase, EC 2.7.7.49) only in that it has two additional amino-terminal amino acids. This protein is soluble in E. coli extracts, is active in reverse transcriptase assays, and shows inhibition profiles with dideoxy-TTP and dideoxy-GTP that are indistinguishable from the viral enzyme. The deletion of 23 amino-terminal or carboxyl-terminal amino acids or the insertion of 5 amino acids at position 143 substantially decreases the polymerizing activity of the HIV reverse transcriptase made in E. coli. The properties of a 51-kDa reverse transcriptase-related protein made in E. coli suggests that the p51 found in the virion probably does not have substantial polymerizing activity. The full-length HIV reverse transcriptase and the various mutant proteins produced in E. coli should be quite useful for structural and biochemical analyses as well as for the production of antibodies.

Genetic analysis of yeast RAS1 and RAS2 genes

We present a genetic analysis of RAS1 and RAS2 of S. cerevisiae, two genes that are highly homologous to mammalian ras genes. By constructing in vitro ras genes disrupted by selectable genes and introducing these by gene replacement into the respective ras loci, we have determined that neither RAS1 nor RAS2 are by themselves essential genes. However, ras1 - ras2 - spores of doubly heterozygous diploids are incapable of resuming vegetative growth. We have determined that RAS1 is located on chromosome XV, 7 cM from ade2 and 63 cM from his3; and RAS2 is located on chromosome XIV, 2 cM from met4 . We have also constructed by site-directed mutagenesis a missense mutant, RAS2val19 , which encodes valine in place of glycine at the nineteenth amino acid position, the same sort of missense mutation that is found in some transforming alleles of mammalian ras genes. Diploid yeast cells that contain this mutation are incapable of sporulating efficiently, even when they contain wild-type alleles.

Homothallic switching of yeast mating type cassettes is initiated by a double-stranded cut in the MAT locus

A double-stranded DNA cut has been observed in the mating type (MAT) locus of the yeast Saccharomyces cerevisiae in cultures undergoing homothallic cassette switching. Cutting is observed in exponentially growing cells of genotype HO HML alpha MAT alpha HMR alpha or HO HMLa MATa HMRa, which switch continuously, but not in a/alpha HO/HO diploid strains, in which homothallic switching is known to be shut off. Stationary phase cultures do not exhibit the cut. Although this site-specific cut occurs in a sequence (Z1) common to the silent HML and HMR cassettes and to MAT, only the Z1 sequence at the MAT locus is cut. The cut at MAT occurs in the absence of the HML and HMR donor cassettes, suggesting that cutting initiates the switching process. An assay for switching on hybrid plasmids containing mata- cassettes has been devised, and deletion mapping has shown that the cut site is required for efficient switching. Thus a double-stranded cut at the MAT locus appears to initiate cassette transposition-substitution and defines MAT as the recipient in this process.

The replication of bacteriophage f1: gene V protein regulates the synthesis of gene II protein

Two filamentous phage gene products are required for the replication of phage DNA. One of these, the gene II protein, is a site-specific endonuclease required for all phage-specific DNA synthesis. The other, the gene V protein, is a single-stranded DNA-binding protein required only for single-strand synthesis. Purified gene V protein, when added to an in vitro protein synthesizing system programmed by f1 DNA, specifically inhibits the synthesis of gene II protein. Inhibition seems to be translational, since synthesis of gene II protein from an RNA template is also inhibited by gene V protein. Gene V protein control of gene II expression can account for the regulation of the level of expression of the filamentous phage genome.

Structure and organization of transposable mating type cassettes in Saccharomyces yeasts

Cell type in Saccharomyces yeasts is regulated by two transposable blocks of DNA, the a and alpha cassettes. There are three loci where either cassette can exist. At the HML and HMR loci the cassettes are not expressed. The cassette at the MAT locus is expressed and controls the cell type. Changes of cell type involve transposition-substitution of cassettes from HML or HMR into MAT. We recently reported the molecular cloning of the alpha cassette at the HML locus, HML alpha, and showed that it contained sequences homologous to HMR and MAT. Using HML alpha as a hybridization probe, we have isolated HMLa, HMR alpha, HMRa, MAT alpha, and MATa. Heteroduplex analysis and restriction endonuclease mapping studies indicate that the a and alpha cassettes differ by a substitution corresponding to about 750 base pairs in alpha and about 600 base pairs in a. The HML, HMR, and MAT loci have regions of homology flanking the position of the a versus alpha substitution. We have used specific chromosome rearrangements fusing MAT and HML and MAT with HMR to orient the cloned sequences on the genetic map and have found that all three genes have the same left-to-right polarity on the chromosome.

Identification and mapping of the transcriptional and translational products of the yeast plasmid, 2mu circle

We have identified two major and approximately ten minor poly(A)-containing RNA species in S. cerevisiae which arise from in vivo transcription of the yeast plasmid, known as 2mu circle. The two major species, which are 1325 and 1275 bases in length, are transcribed from the two unique halves of the plasmid and extend into the inverted repeat sequences which separate the unique regions. The map positions of the minor transcripts, which range in length from 350 to 2600 bases, indicate that except for a small region of the genome in which no transcription is observed, both strands of the entire 2mu circle genome are transcribed. We also present evidence demonstrating that RNA transcribed from 2mu circular DNA is used to program the synthesis of specific proteins in yeast: that is, yeast RNA complementary to 2mu circle DNA can be translated in vitro to produce specific polypeptides of substantial size. Finally, the pattern of transcription of 2mu circle suggests the possibility that messenger RNA species are derived by cleavage of larger transcripts, and in addition, that the intramolecular recombination of 2mu circle which occurs in yeast functions as a genetic switch to allow separate expression of two sets of genes on the 2mu circle genome.

Nonoperative management of biliary ductal stenosis. Report of a most unusual case

A patient with documented iatrogenic stricture of the common duct is reported. Certain very unusual characteristics of this lesion suggested that it was not precisely similar to ordinary biliary strictures and that nonoperative care was worthy of trial. No reconstructive operation has been done. The strictured segment has resolved so that the patient is completely asymptomatic and has no direct or indirect laboratory or radiographic evidence of biliary obstruction.