Volatile profiling as a potential biochemical marker for validation of gamma irradiation derived putative mutants in polyembryonic genotypes of mango (Mangifera indica L.).

Introduction: Putative mutants were generated through gamma irradiation in the polyembryonic mango genotype Nekkare. The putative mutant progenies along with control seedlings and mother plants were evaluated by comparing the compositions and relative proportions of their major volatile compounds. Methods: Volatile profiling was done using headspace-solid phase micro-extraction (HS SPME) method coupled with gas chromatography-mass spectrometry (GC-MS MS). Furthermore, characterisation of putative mutants and control seedlings was carried out using simple sequence repeat (SSR) markers to ascertain the genetic diversity present in the samples under study. Results: Monoterpenes were the most abundant volatile compound in all the studied samples (ranging from 34.76% to 91.41%) out of which I-Phellandrene and cis-Ocimene formed the major fraction in mother plants (20.45%-21.86% and 16.17%-21.27%, respectively) and control seedlings (23.32%-24.95% and 18.95%-20.81%, respectively), while beta-Phellandrene was dominant in the selected putative mutant samples (2.34%-29.53%). Among sesquiterpenes, trans-Caryophyllene was detected only in the putative mutant samples (0.10%-30.18%). Grouping together of mother plants and control seedlings was seen in the cluster analysis, while the putative mutants grouped apart from them suggesting genetic diversity. Genetic distance between the mother plants and control seedlings ranged from 0.97 to 2.73, while between putative mutants, control seedlings, and mother plants, it ranged from 6.54 to 9.82. SSR-based characterisation of putative mutant seedlings showed that mutation caused variability in the treated population. This was evident from the high allelic richness ranging from 4 to 12 with a mean of 7 and a higher mean Shannon's Information Index (1.50) of the putative mutant population. Discussion: The study demonstrates that volatile profiling and molecular characterisation using SSR markers could be used as a tool to detect variation in a mutated population. In addition, volatile profiling can be used to validate putative mutants in polyembryonic mango genotypes where the seedlings of nucellar origin are similar to mother plants.

Comparative transcriptome analysis provides novel insights into molecular response of salt-tolerant and sensitive polyembryonic mango genotypes to salinity stress at seedling stage.

Introduction: Increased soil salinity in the recent years has adversely affected the productivity of mango globally. Extending the cultivation of mango in salt affected regions warrants the use of salinity tolerant/resistant rootstocks. However, the lack of sufficient genomic and transcriptomic information impedes comprehensive research at the molecular level. Method: We employed RNA sequencing-based transcriptome analysis to gain insight into molecular response to salt stress by using two polyembryonic mango genotypes with contrasting response to salt stress viz., salt tolerant Turpentine and salt susceptible Mylepelian. Results: RNA sequencing by Novaseq6000 resulted in a total of 2795088, 17535948, 7813704 and 5544894 clean reads in Mylepelian treated (MT), Mylepelian control (MC), Turpentine treated (TT) and Turpentine control (TC) respectively. In total, 7169 unigenes annotated against all the five public databases, including NR, NT, PFAM, KOG, Swissport, KEGG and GO. Further, maximum number of differentially expressed genes were found between MT and MC (2106) followed by MT vs TT (1158) and TT and TC (587). The differentially expressed genes under different treatment levels included transcription factors (bZIP, NAC, bHLH), genes involved in Calcium-dependent protein kinases (CDPKs), ABA biosynthesis, Photosynthesis etc. Expression of few of these genes was experimentally validated through quantitative real-time PCR (qRT-PCR) and contrasting expression pattern of Auxin Response Factor 2 (ARF2), Late Embryogenesis Abundant (LEA) and CDPK genes were observed between Turpentine and Mylepelian. Discussion: The results of this study will be useful in understanding the molecular mechanism underlying salt tolerance in mango which can serve as valuable baseline information to generate new targets in mango breeding for salt tolerance.

Overcoming the coupled climate and biodiversity crises and their societal impacts.

Earth's biodiversity and human societies face pollution, overconsumption of natural resources, urbanization, demographic shifts, social and economic inequalities, and habitat loss, many of which are exacerbated by climate change. Here, we review links among climate, biodiversity, and society and develop a roadmap toward sustainability. These include limiting warming to 1.5°C and effectively conserving and restoring functional ecosystems on 30 to 50% of land, freshwater, and ocean "scapes." We envision a mosaic of interconnected protected and shared spaces, including intensively used spaces, to strengthen self-sustaining biodiversity, the capacity of people and nature to adapt to and mitigate climate change, and nature's contributions to people. Fostering interlinked human, ecosystem, and planetary health for a livable future urgently requires bold implementation of transformative policy interventions through interconnected institutions, governance, and social systems from local to global levels.

Nutrients cause grassland biomass to outpace herbivory.

Human activities are transforming grassland biomass via changing climate, elemental nutrients, and herbivory. Theory predicts that food-limited herbivores will consume any additional biomass stimulated by nutrient inputs ('consumer-controlled'). Alternatively, nutrient supply is predicted to increase biomass where herbivores alter community composition or are limited by factors other than food ('resource-controlled'). Using an experiment replicated in 58 grasslands spanning six continents, we show that nutrient addition and vertebrate herbivore exclusion each caused sustained increases in aboveground live biomass over a decade, but consumer control was weak. However, at sites with high vertebrate grazing intensity or domestic livestock, herbivores consumed the additional fertilization-induced biomass, supporting the consumer-controlled prediction. Herbivores most effectively reduced the additional live biomass at sites with low precipitation or high ambient soil nitrogen. Overall, these experimental results suggest that grassland biomass will outstrip wild herbivore control as human activities increase elemental nutrient supply, with widespread consequences for grazing and fire risk.

Soil net nitrogen mineralisation across global grasslands.

Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important for productivity and nutrient cycling. The balance between mineralisation and immobilisation (net Nmin) varies with soil properties and climate. However, because most global-scale assessments of net Nmin are laboratory-based, its regulation under field-conditions and implications for real-world soil functioning remain uncertain. Here, we explore the drivers of realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We find that realised Nmin is largely explained by temperature of the wettest quarter, microbial biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised Nmin, but contributes to explain realised net Nmin when combined with soil and climatic variables. We provide novel insights of global realised soil net Nmin and show that potential soil net Nmin data available in the literature could be parameterised with soil and climate data to better predict realised Nmin.

Studies on pelletised lithium magnesium borate TL material for eye lens dosimetry.

Recent epidemiological studies in various cohorts confirm that radiation induced cataract may occur at a threshold dose as low as 0.5 Gy. ICRP has recognised the higher radiosensitivity of eye lens and recommended to reduce annual eye lens dose limit from 150 to 20 mSv. Present dosimetry for eye lens is largely based on LiF based dosimeters. The present work is an attempt towards using near tissue equivalent lithium borate material namely lithium magnesium borate doped with terbium (LMB:Tb) in eye lens dosimetry. The material in powder form was synthesised using solid state sintering method and pelletised using poly tetra fluoro ethylene (PTFE) as binding agent. It was observed that 130 mg of 1 mm thick LMB:Tb pellet bound with PTFE showed stable glow curve structure and attractive dosimetric features in terms of sensitivity, fading, linearity, reusability etc. A proposal of 1.5 mm Teflon encapsulation corresponding to tissue equivalent thickness of 3 mm was put forward for an ideal dosimeter for the measurement in terms of Hp(3). Energy and angular dependence studies based on FLUKA simulations suggest a flat response for the prototype design. In addition to PTFE, various tissue equivalent encapsulations such as polyimide, polyamide 6 and PMMA were also evaluated using FLUKA code.

(2E)-2-Benzyl-idene-9-phenyl-3,4-di-hydro-acridin-1(2H)-one.

In the title compound, C26H19NO, the plane of the aromatic heterocycle makes a dihedral angle of 75.22 (4)° with that of the attached phenyl ring. In the crystal, mol-ecules are connected by C-H⋯O inter-actions, generating R 2 (2)(12) dimers. These dimers are further connected by C-H⋯π inter-actions, linking the mol-ecules into chains running along the a-axis direction.

(1R*,3'S*,4'R*)-4'-(4-Chloro-phen-yl)-3'-[(4-hy-droxy-2-oxo-1,2-dihydro-quinolin-3-yl)carbon-yl]-1'-methyl-spiro-[ace-naphthyl-ene-1,2'-pyrrolidin]-2-one.

The title compound, C(32)H(23)ClN(2)O(4), has a quinoline, a chloro-phenyl and an acenaphthalene ring system attached to a central pyrrolidine ring, which has three stereogenic centers. Nevertheless, the compound crystallizes as a racemate with two mol-ecules of identical chirality in the asymmetric unit. They differ in the conformation of the five-membered pyrrolidine ring; in one molecule it has an envelope conformation, while in the other molecule it has a twisted conformation. In each molecule there is an intra-molecular O-H⋯O hydrogen bond making an S(6) ring motif. In the crystal, pairs of N-H⋯O hydrogen bonds produce inversion dimers with R(2) (2)(8) motifs. There are also C-H⋯O interactions present. The crystal structure contains voids (60 Å(3)) within which there is no evidence of solvent mol-ecules.

4-Hydr-oxy-3-(1'-methyl-2-oxo-4'-phenyl-spiro-[indoline-3,2'-pyrrolidine]-3'-yl-carbon-yl)quinolin-2(1H)-one.

In the title compound, C(28)H(23)N(3)O(4), the dihedral angle between the quinoline and indole ring systems is 29.30 (5)°. The pyrrolidine ring adopts a twist conformation. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif. A weak intra-molecular C3-H3⋯O3 inter-action is also observed. In the crystal, mol-ecules are linked by two sets of N-H⋯O hydrogen bonds, forming centrosymmetric dimers containing two R(2) (2)(8) ring motifs. The dimers are linked via C-H⋯π inter-actions.

Modulation of biochemical circadian rhythms during long-term melatonin treatment in rats.

INTRODUCTION: The influences of chronic administration of low and high doses of melatonin on the characteristics of circadian rhythms of glucose, reduced glutathione, total protein were studied, in order to investigate whether melatonin could modulate these rhythms differently. METHODS: Pharmacological doses of melatonin (0.5 mg/kg and 1.0mg/kg body weight) were administered chronically for 45 days to Wistar rats, and 24-hour rhythms of glucose, reduced glutathione (GSH), total protein and melatonin (MLT) were studied under semi-natural (LD 12:12 hours) conditions. RESULTS: Exogenous melatonin administered caused delays in the acrophase of glucose, total protein and melatonin rhythms, whereas advances in the acrophases of reduced glutathione were observed. This indicated that the chronic administration of melatonin could act as the modulated internal zeitgeber and this could be the reason for altered acrophase (peak time of the variable) and other characteristics of rhythms in the melatonin-treated groups. Significant dose-dependent effects of melatonin were absent in the study. CONCLUSION: The present study demonstrates that the exogenous administration of melatonin could influence the biochemical rhythms.

Audit in the management of gliomas.

A retrospective study of 139 glioma patients was conducted in an effort to audit management. Factors affecting survival were studied using a Cox Proportional Hazard Model. These factors included age, sex, location, grade, type of surgery, use of radiotherapy, presenting symptoms, Karnofsky score on admission and Karnofsky score 3 months following surgery. Lower grade, high Karnofsky score on admission, radiotherapy and frontal location were associated with better survival. There was statistically insignificant evidence that the other factors had an influence on survival. Patients presenting with a poor neurological score were treated with burrhole biopsy alone. Only 10% of these patients survived more than 6 months. On the other hand, 26% of patients who had craniotomy on the basis of reasonable clinical status lived less than 6 months. Sixty-six per cent of patients in this craniotomy group were aged 60 years or over, and 66% of those aged over 60 had a Karnofsky score of less than 70. We conclude that careful judgement is required before subjecting patients aged over 60, especially those with a low Karnofsky score, to radical therapy.

The use of placenta in a microvascular exercise.

Twenty-five human placentas were studied for suitability in a microvascular exercise. The size and useful length of vessels were measured, and different microvascular anastomoses were performed. The size of the placenta vessels compared well with reported sizes of intracranial arteries. We suggest the use of placenta by neurosurgeons as complementary to experimental animals in microvascular training.

Evaluation and mode of action of nonsteroidal antiestrogens.

PIP: The search for postcoitally effective antifertility agents has resulted in the synthesis of many nonsteroidal compounds which are potent antiestrogens. They bring about their antifertility/antiimplantation action through biological properties affecting the normal physiology of the oviduct and uterus during the preimplantation stages of pregnancy. The mode of action of these compounds (though clear in laboratory rodents) remains speculative in primates. Investigations on the mechanisms of action of antiestrogens had indicated the prerequisites of the ideal postcoital antifertility agent: 1) inhibition of any event in the female genital tract from ovulation to ovum implantation (action may be on fertilzation, tubal transport of ova, or preparation of the uterus for ovum implantation), 2) effectiveness for a prolonged period of time after a single administration, 3) active when administered orally or sc, and 4) minimum side effects.^ieng

Mode of action of a new non-steroidal post-coital antifertility agent (centchroman: 67/20 CDRI) in rats.

PIP: The estrogenicity and antiestrogenicity of the compound Centchroman, 67/20 CDRI, trans-2-2-dimethyl 1-3 phenyl-4-p(beta-pyrrolidinoithoxy phenyl) 7-methoxy chroman hydrochloride, a synthetic nonsteroidal compound, was studied using uterine and liver glycogen and uterine sialic acid as biochemical parameters. Estradiol caused significant increases in uterine and liver glycogen 6 and 18 hours after administration; Centchroman 67/20 caused a marked increase in uterine glycogen at 6 hrs which plateaued at this level for 48 hrs after the administration. Liver glycogen showed a steady increase even 48 hrs after the administration of 67/20. Uterine sialic acid in estrogen-treated rats reached a peak level at 6 hrs, decreased significantly by 18 hrs, and plateaued at this level up to 48 hrs. Compound 67/20, on the other hand, caused an increase in uterine sialic acid 18 hrs after the administration of the drug. Pretreatment with the compound for either 6 or 48 hrs before administration of 17-beta-estradiol inhibited the estradiol-induced increase in uterine and liver glycogen and also uterine sialic acid. However, simultaneous administration of the compound with 17-beta-estradiol was effective only in inhibiting the estradiol-induced increase in uterine sialic acid. In light of the present data, it is concluded that the antiimplantation/antifertility action of the compound 67/20 may be due to its inherent estrogenic and antiestrogenic properties.^ieng