Increases in leaf nitrogen concentration and leaf area did not enhance spur survival and return bloom in almonds (<Emphasis Type="Italic">Prunus dulcis</Emphasis> [Mill.] DA Webb)

Mature almond trees bear fruit mainly on short shoots called spurs, with only a small percentage of fruit produced laterally on long 1-year-old shoots. As a result, maintenance of large numbers of healthy spurs per tree is critical for fruit production. However, spurs that bear fruit have lower leaf area, leaf nitrogen content, and CO₂ assimilation rate than non-fruiting spurs. This has been correlated with reduced percentages of spur survival and return bloom the following season. Thus, we hypothesized that spur leaf area, and ultimately spur health could be enhanced through application of foliar sprays and soil nitrogen treatments that would enhance leaf nitrogen content and spur leaf area. To test our hypothesis, we selected almond trees exhibiting significant yield differences as a consequence of differential soil rates of nitrogen fertilization (N rate) for three prior years (140, 224, and 392 kg/ha). In each tree, three spur types [non-fruiting spurs (F0); spurs with one fruit (F1); spurs with two fruit (F2)] were selected on the east side of the canopy and tracked for one complete season (2011–2012). Four foliar treatments (nutrient replacement, nutrient replacement with biostimulant, nitrogen, and non-spray) were directly applied to individual spurs in each N rate in the spring of 2011 and characteristic such as leaf nitrogen, and fruit quality were recorded throughout the season. In winter of 2012, spur survival and return bloom were addressed through individual visual inspection of the tagged spurs. In this experiment, soil and foliar N treatments effectively increased spur leaf area, fruit, and leaf nitrogen concentration. In the high N treatment, the leaf nitrogen values exceeded the critical nitrogen concentration established for almond trees and the critical leaf area for spur survival and blooming thresholds established by past research in this area. However, none of these positive changes in leaf N or leaf area improved spur survival and/or return boom of any spur type. Indeed, survival and hull + shell weight tended to be lower in the population of fruiting spurs with the highest leaf area and leaf nitrogen concentration and the return bloom probabilities were always lower in fruiting spurs than in non-fruiting spurs, independent of the nitrogen rate. These results and the relationship between nitrogen rate and spur survival are discussed.     

Copper complex derived from <Emphasis Type="Italic">S</Emphasis>-benzyldithiocarbazate and 3-acetylcoumarin induced apoptosis in breast cancer cell

Copper complexes have been widely studied for the anti-tumour application as cancer cells are reported to take up greater amounts of copper than normal cells. Preliminary study revealed that the newly synthesised copper complex [Cu(SBCM)₂] displayed marked anti-proliferative towards triple-negative MDA-MB-231 breast cancer cells. Therefore, Cu(SBCM)₂ has great potential to be developed as an agent for the management of breast cancer. The present study was carried out to investigate the mode of cell death induced by Cu(SBCM)₂ towards MDA-MB-231 breast cancer cells. The inhibitory and morphological changes of MDA-MB-231 cells treated with Cu(SBCM)₂ was determined by using MTT assay and inverted light microscope, respectively. The safety profile of Cu(SBCM)₂ was also evaluated towards human dermal fibroblast (HDF) normal cells. Confirmation of apoptosis and cell cycle arrest were determined by flow cytometry analysis. The expression of p53, Bax, Bcl-2 and MMP2 protein were detected with western blot analysis. Cu(SBCM)₂ significantly inhibited the growth of MDA-MB-231 cells in a dose-dependent manner with GI₅₀ 18.7?±?3.06 µM. Indeed, Cu(SBCM)₂ was less toxic towards HDF normal cells with GI₅₀ 31.8?±?4.0 µM. Morphological study revealed that Cu(SBCM)₂-treated MDA-MB-231 cells experienced cellular shrinkage, membrane blebbing, chromatin condensation and formation of apoptotic bodies, suggesting that Cu(SBCM)₂ induced apoptosis in the cells, which was confirmed by Annexin-V/PI flow cytometry analysis. It was also found that Cu(SBCM)₂ induced G₂/M phase cell cycle arrest towards MDA-MB-231 cells. The induction of apoptosis and cell cycle arrest in the present study is possibly due to the down-regulation of the mutant p53 and MMP2 protein. In conclusion, Cu(SBCM)₂ can be developed as a targeted therapy for the treatment of triple-negative breast cancer.     

Prediction of leaf nitrogen from early season samples and development of field sampling protocols for nitrogen management in Almond (Prunus dulcis [Mill.] DA Webb)

Background and aim

Protocols for leaf sampling in deciduous tree crops are commonly executed too late in the season and do not adequately consider field variability to be effectively used to guide N management. The goal of this study was to develop improved sampling strategies to optimize nitrogen management in deciduous tree crops.

Method

Leaf nutrient concentration from individual trees in four mature commercial orchards was collected (n =1148) for three consecutive seasons to develop nitrogen prediction models and to estimate the distribution of N values in orchards in July. Spatial variance analysis was used to determine optimal sampling strategies.

Results

Leaf nitrogen concentration in summer can be predicted (r²?=?0.9) from the leaf N and B concentration in spring with the sum of K, Ca, and Mg equivalents. Mean field leaf nutrient concentration can be obtained by collecting one pooled sample per management zone composed of 30 trees each of which are at least 30 m apart. Using these methods the percentage of trees with leaf N above the recommended July critical value can be predicted accurately.

Conclusions

Optimized methods for sample collection and models to predict mid-season leaf N from early season samples can be used to improve N management in deciduous tree crops.     

Effect of Particle Shape on Dry Particle Inhalation: Study of Flowability, Aerosolization, and Deposition Properties

The shape effects of dry particles on flowability, aerosolization, and deposition properties in inhalation drug delivery are studied. The properties are compared with similar size range particles of different shapes such as sphere, needle, cube, plate, and pollen. Flowability of the particles is characterized by Carr’s compressibility index and angle of slide (θ) method. The aerosolization and deposition properties of the particles are studied in vitro using an eight-stage Anderson cascade impactor with a Rotahaler®. Pollen-shaped particles are found to exhibit better flowability, higher emitted dose, and higher fine particle fraction than particles of other shapes in similar size range. They showed minimum θ of 35° and maximum emitted dose of 87% and fine particle fraction of 16%. The use of pollen-shaped particles can be a potential improvement in dry particle inhalation.     

SMAD2 rs4940086 heterozygosity increases the risk of cervical cancer development among the women in Bangladesh

Molecular Biology Reports - SMAD2 is a critical signal transducer molecule in the TGFβ- SMAD pathway which is also known for its tumor suppressor role. Genetic variations in SMAD2 render cells...     

Altitudinal distribution of the entire invasive small mammal guild in the eastern dryland zone of New Zealand’s Southern Alps

New Zealand faces significant ecological problems caused by the introduction of a variety of invasive small mammal species. Many of these species originate from temperate to subarctic climates and occur across wide elevations in their native range, and so arrived predisposed to adapt to a variety of habitats and bioclimatic zones in their new environs, including the alpine zone. Almost all of New Zealand’s invasive small mammal species have been recorded in the country’s alpine zones, yet neither the altitudinal distribution nor the extent to which such species use high elevation areas has been clearly defined. We conducted extensive camera trap surveys in summer to autumn periods of 2019 and 2020 across an elevation range of 500–2250 m above sea level, and used detection rates and occupancy modelling to reveal the altitudinal distributions and habitat associations of all 10 invasive small mammals that occur in the dryland zone of the central South Island. We found altitudinal distributions varied greatly across species, and that while most exhibited decreasing detection rates and site occupancy probabilities with increasing elevation, some used the subalpine and alpine zones to a greater degree than adjacent lower elevations. There were clear habitat associations, as well as interspecific associations that helped to explain the altitudinal distribution of some species. Understanding how such factors influence the distribution of invasive small mammals has both broad implications for invasive species management, and direct applications in evaluating threats to native taxa, advancing management strategies, and benchmarking distributions in a changing climate.

     

Sharing of Needles and Syringes among Men Who Inject Drugs: HIV Risk in Northwest Bangladesh

Introduction

Injection drug use is prevalent in northwestern Bangladesh. We sought to explore the context of needle/syringe sharing among persons who inject drugs (PWID), examining risk exposures to blood-borne infections like the human immunodeficiency virus (HIV) and hepatitis in a region where these dual epidemics are likely to expand.

Methods

We used a qualitative research approach to learn about injection practices, conducting 60 in-depth interviews among PWID. We then conducted 12 focus group discussions (FGDs) that generated a checklist of salient issues, and followed up with personal observations of typical days at the drug-use venues. Content and interpretative frameworks were used to analyze qualitative information and socio-demographic information, using SPSS software.

Results

We found that needle/syringe-sharing behaviours were integrated into the overall social and cultural lives of drug users. Sharing behaviours were an central component of PWID social organization. Sharing was perceived as an inherent element within reciprocal relationships, and sharing was tied to beliefs about drug effects, economic adversity, and harassment due to their drug user status. Carrying used needles/syringes to drug-use venues was deemed essential since user-unfriendly needle-syringe distribution schedules of harm reduction programmes made it difficult to access clean needles/syringes in off-hours. PWID had low self-esteem. Unequal power relationships were reported between the field workers of harm reduction programmes and PWID. Field workers expressed anti-PWID bias and judgmental attitudes, and also had had misconceptions about HIV and hepatitis transmission. PWID were especially disturbed that no assistance was forthcoming from risk reduction programme staff when drug users manifested withdrawal symptoms.

Conclusion

Interventions must take social context into account when scaling up programmes in diverse settings. The social organization of PWID include values that foster needle-syringe sharing. Utilization and impact of risk reduction programmes might be improved with expanded clean needle/syringe distribution at times and venues convenient for PWID, better trained and non-judgmental staff, and medical assistance for health problems, including drug withdrawal symptoms.     

Xlink-identifier: an automated data analysis platform for confident identifications of chemically cross-linked peptides using tandem mass spectrometry

Chemical cross-linking combined with mass spectrometry provides a powerful method for identifying protein-protein interactions and probing the structure of protein complexes. A number of strategies have been reported that take advantage of the high sensitivity and high resolution of modern mass spectrometers. Approaches typically include synthesis of novel cross-linking compounds, and/or isotopic labeling of the cross-linking reagent and/or protein, and label-free methods. We report Xlink-Identifier, a comprehensive data analysis platform that has been developed to support label-free analyses. It can identify interpeptide, intrapeptide, and deadend cross-links as well as underivatized peptides. The software streamlines data preprocessing, peptide scoring, and visualization and provides an overall data analysis strategy for studying protein-protein interactions and protein structure using mass spectrometry. The software has been evaluated using a custom synthesized cross-linking reagent that features an enrichment tag. Xlink-Identifier offers the potential to perform large-scale identifications of protein-protein interactions using tandem mass spectrometry.     

Treatment with captopril abrogates the altered expression of alpha1 macroglobulin and alpha1 antiproteinase in sera of spontaneously hypertensive rats

Background

Proteins that are associated with hypertension may be identified by comparing the 2-dimensional gel electrophoresis (2-DE) profiles of the sera of spontaneously hypertensive rats (SHR) with those generated from normotensive Spraque-Dawley rats (SDR).

Results

Five proteins of high abundance were found to be significantly altered when the 2-DE serum profiles of the SHR were compared to those that were similarly generated from the SDR. Analysis by mass spectrometry and database search identified the proteins as retinol binding protein 4, complement C3, albumin (19.9 kDa fragment), alpha1 macroglobulin and alpha1 antiproteinase, which are all known to be associated with hypertension. The altered expression of the two latter proteins was found to be abrogated when similar analysis was performed on sera of the SHR that were treated with captopril.

Conclusion

Our data suggests that serum alpha1 macroglobulin and alpha1 antiproteinase are potentially useful complementary biomolecular indicators for monitoring of hypertension.