Art under the Microscope.

In March 2018, Greece issued five commemorative stamps that show a beautiful mélange of art and science. Images are, however, genuine views captured through light microscopy of stained human tissue during histopathological examination. Many will remember having drawn such diagrams in their histology and pathology journals during their medical school years. The microscopic images are photographed beautifully by Dr Maria Lambropaulou. She is an Associate Professor of Histology-embryology at the Medical Department of the Democritus University of Thrace, Greece.

An Overview of Systematic Reviews and Meta-Analyses on the Effect of Medication Interventions Targeting Polypharmacy for Frail Older Adults.

Frailty refers to the lack of resilience and a reduction in a person's ability to recover following a health problem, and it is increasingly becoming a challenging aspect of ageing populations. Many older adults are exposed to polypharmacy; i.e., they continue to be on medications without timely re-evaluation. Medication reviews have proven successful in managing polypharmacy in the general population, but there is uncertainty regarding their effect among frail older adults. This overview of published systematic reviews assesses the impact of medication reviews on polypharmacy in frail older adults. Embase was searched from its inception to January 2021 and 28 systematic reviews were identified, out of which 10 were included in the overview. Medication reviews were the most common intervention in 8 out of 10 systematic reviews. The frailty score was reported as an outcome in one systematic review that found no evidence for fundamental pharmacological effects on frailty. Six systematic reviews reported a statistically significant reduction in the number of inappropriately prescribed medications. Four systematic reviews reported on hospital admissions, with two of them reporting a decrease in hospitalisations. The quality assessment was moderate in six and critically low in four of the systematic reviews. We conclude that medication reviews help in reducing the use of inappropriate medications in frail older adults, but that there is insufficient evidence in terms of frailty score and hospital admissions.

Functional Significance of Different Milk Constituents in Modulating the Gut Microbiome and Infant Health.

Human milk, the gold standard for optimal nourishment, controls the microbial composition of infants by either enhancing or limiting bacterial growth. The milk fat globule membrane has gained interest in gut-related functions and cognitive development. The membrane proteins can directly interact with probiotic bacteria, influencing their survival and adhesion through gastrointestinal transit, whereas membrane phospholipids increase the residence time of probiotic bacteria in the gut. The commensal bacteria in milk act as the initial inoculum in building up the gut colonization of an infant, whereas oligosaccharides promote proliferation of beneficial microorganisms. Interestingly, milk extracellular vesicles are also involved in influencing the microbiota composition but are not well-explored. This review highlights the contribution of different milk components in modulating the infant gut microbiota, particularly the fat globule membrane, and the complex interplay between host- and brain-gut microbiota signaling affecting infant and adult health positively.

Comparative morphometric evaluation of the brainstem in neurodegenerative diseases with healthy individuals using magnetic resonance imaging.

OBJECTIVE: Measurement of a component within the reference value is a widely used parameter in Biomedical Science. This study highlights the value of morphometric changes in healthy individuals' brainstem structure and their application in the detection and diagnosis of neurodegenerative disorders. METHODS: This retrospective study included magnetic resonance (MR) images of 50 healthy individuals without neurological diseases, 35 clinically diagnosed individuals with Parkinson's disease (PD), and 12 individuals with Progressive Supranuclear Palsy (PSP). Measurements of midbrain area, pons area, ratio of midbrain to pons area, superior profile of midbrain, thickness of substantia nigra (SN), cerebral crus width, interpeduncular distance, and concavity of the crus were analysed as per the standard protocol. RESULTS: Patients with PD had mean anteroposterior diameter of 1.11 ± 0.1 cm, which was more than the control group and PSP patients. Additionally, PSP patients showed the least midbrain and pons area of 1.06 ± 0.34 and 4.01 ± 1.2 sq.cm, respectively, compared to other groups. The ratio of midbrain to pons area was the least among PSP patients (0.21 ± 0.06 cm). Mean thickness of the right and left middle cerebellar peduncles (1.25 ± 0.19 and 1.24 ± 0.17 cm) was less in the PD group. The width of the SN gradually reduced in PD and more so in PSP patients. The convex superior profile of the midbrain was a consistent feature in all groups. CONCLUSION: This study highlights the value of morphometrics of the brainstem profile in differentiating neurodegenerative diseases among aged, healthy individuals when combined with their clinical data.

Comparative Analysis of Milk Triglycerides Profile between Jaffarabadi Buffalo and Holstein Friesian Cow.

Milk lipids are known for a variety of biological functions, however; little is known about compositional variation across breeds, especially for Jaffarabadi buffalo, an indigenous Indian breed. Systematic profiling of extracted milk lipids was performed by mass spectrometry across summer and winter in Holstein Friesian cow and Jaffarabadi buffalo. Extensive MS/MS spectral analysis for the identification (ID) of probable lipid species using software followed by manual verification and grading of each assigned lipid species enabled ID based on (a) parent ion, (b) head group, and (c) partial/full acyl characteristic ions for comparative profiling of triacylglycerols between the breeds. Additionally, new triacylglycerol species with short-chain fatty acids were reported by manual interpretation of MS/MS spectra and comparison with curated repositories. Collectively, 1093 triacylglycerol species belonging to 141 unique sum compositions between the replicates of both the animal groups were identified. Relative quantitation at sum composition level followed by statistical analyses revealed changes in relative abundances of triacylglycerol species due to breed, season, and interaction effect of the two. Significant changes in triacylglycerols were observed between breeds (81%) and seasons (59%). When the interaction effect is statistically significant, a higher number of triacylglycerols species in Jaffarabadi has lesser seasonal variation than Holstein Friesian.

Selective enrichment of milk fat globules using functionalized polyvinylidene fluoride membrane.

We report on the development of a functionalized membrane-based technology for selective enrichment of milk fat globules from raw bovine milk. Functionalization was conducted by in situ polymerization of acrylic acid within a polyvinylidene fluoride membrane, followed by the electrostatic attachment of a cationic polymer to impart a net positive charge. The functionalized membrane-based technology enabled a one-step method of selective separation of globules directly from milk-based on size and charge. The presence of globules in the eluate was confirmed by fluorescence microscopy. Quantification of the extracted phospholipids from globules in the eluant revealed a significantly higher amount of polar lipids than the permeate. Our study describes a comprehensive analysis of selective enrichment of fat globules using a functionalized membrane and demonstrates the beneficial effect of extracted phospholipids from enriched fat globules.

Characterization of difference in structure and function of fresh and mastitic bovine milk fat globules.

Characterization of milk fat globule (MFG) was performed to investigate the difference in MFG membrane (MFGM) between fresh and mastitis Holstein Friesian cow milk. Lipid distribution investigated by exogenous phospholipids using microscopy showed higher phospholipid content in fresh compared to mastitic MFGM. Xanthine oxidase assay indicative of membrane impairment revealed lower activity in mastitic samples compared to fresh globules. Of note, significantly higher roughness of globule surface and zeta potential was observed in mastitis compared to fresh globules. Influence of globule membrane on the interaction with L. fermentum demonstrated preferential adhesion of bacteria to fresh compared to mastitic globules including enhanced extent of binding. Results of the present study provides an insight of the interfacial changes occurring at the globule surface as well as highlighting the importance of selective bacterial interaction with milk components for the potential development of functional food with relevance to human health.

Cinnamate-CoA ligase is involved in biosynthesis of benzoate-derived biphenyl phytoalexin in Malus × domestica 'Golden Delicious' cell cultures.

Apple (Malus sp.) and other genera belonging to the sub-tribe Malinae of the Rosaceae family produce unique benzoic acid-derived biphenyl phytoalexins. Cell cultures of Malus domestica cv. 'Golden Delicious' accumulate two biphenyl phytoalexins, aucuparin and noraucuparin, in response to the addition of a Venturia inaequalis elicitor (VIE). In this study, we isolated and expressed a cinnamate-CoA ligase (CNL)-encoding sequence from VIE-treated cell cultures of cv. 'Golden Delicious' (M. domestica CNL; MdCNL). MdCNL catalyses the conversion of cinnamic acid into cinnamoyl-CoA, which is subsequently converted to biphenyls. MdCNL failed to accept benzoic acid as a substrate. When scab-resistant (cv. 'Shireen') and moderately scab-susceptible (cv. 'Golden Delicious') apple cultivars were challenged with the V. inaequalis scab fungus, an increase in MdCNL transcript levels was observed in internodal regions. The increase in MdCNL transcript levels could conceivably correlate with the pattern of accumulation of biphenyls. The C-terminal signal in the MdCNL protein directed its N-terminal reporter fusion to peroxisomes in Nicotiana benthamiana leaves. Thus, this report records the cloning and characterisation of a cinnamoyl-CoA-forming enzyme from apple via a series of in vivo and in vitro studies. Defining the key step of phytoalexin formation in apple provides a biotechnological tool for engineering elite cultivars with improved resistance.

The unusual glycine-rich C terminus of the Acinetobacter baumannii RNA chaperone Hfq plays an important role in bacterial physiology.

Acinetobacter baumannii is a Gram-negative nosocomial pathogen that causes soft tissue infections in patients who spend a long time in intensive care units. This recalcitrant bacterium is very well known for developing rapid drug resistance, which is a combined outcome of its natural competence and mobile genetic elements. Successful efforts to treat these infections would be aided by additional information on the physiology of A. baumannii Toward that end, we recently reported on a small RNA (sRNA), AbsR25, in this bacterium that regulates the genes of several efflux pumps. Because sRNAs often require the RNA chaperone Hfq for assistance in binding to their cognate mRNA targets, we identified and characterized this protein in A. baumannii The homolog in A. baumannii is a large protein with an extended C terminus unlike Hfqs in other Gram-negative pathogens. The extension has a compositional bias toward glycine and, to a lower extent, phenylalanine and glutamine, suggestive of an intrinsically disordered region. We studied the importance of this glycine-rich tail using truncated versions of Hfq in biophysical assays and complementation of an hfq deletion mutant, finding that the tail was necessary for high-affinity RNA binding. Further tests implicate Hfq in important cellular processes of A. baumannii like metabolism, drug resistance, stress tolerance, and virulence. Our findings underline the importance of the glycine-rich C terminus in RNA binding, ribo-regulation, and auto-regulation of Hfq, demonstrating this hitherto overlooked protein motif to be an indispensable part of the A. baumannii Hfq.

A novel function for globulin in sequestering plant hormone: Crystal structure of Wrightia tinctoria 11S globulin in complex with auxin.

Auxin levels are tightly regulated within the plant cell, and its storage in the isolated cavity of proteins is a measure adopted by cells to maintain the availability of auxin. We report the first crystal structure of Wrightia tinctoria 11S globulin (WTG) in complex with Indole-3-acetic acid (IAA), an auxin, at 1.7 Å resolution. WTG hexamers assemble as a result of the stacking interaction between the hydrophobic surfaces of two trimers, leaving space for the binding of charged ligands. The bound auxin is stabilized by non-covalent interactions, contributed by four chains in each cavity. The presence of bound ligand was confirmed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and high-resolution mass spectrometry (HRMS). Here, we hypothesize that the cleavage of globulins by endopeptidases leads to the movement of the hydrophilic loop region from the surface to the periphery, leaving space for the binding of auxin, and promotes hexamer formation. As the process of germination proceeds, there is a change in the pH, which induces the dissociation of the hexamer and the release of auxin. The compact hexameric assembly ensures the long-term, stable storage of the hormone. This suggests a role for globulin as a novel player in auxin homeostasis.

Challenges and opportunities of bovine milk analysis by mass spectrometry.

Bovine milk and its products (e.g. cheese, yoghurt) are an important part of human diet with beneficial effects for all ages. Although analyses of different milk components (e.g. proteins, lipids) pose huge challenges, the use of mass spectrometric (MS)-based techniques is steadily improving our understanding of the complexity of the biological traits that effect milk yield and its components to meet the global demand arising from population growth. In addition, different milk constituents have various applications in veterinary research and medicine, including early disease diagnosis. The aim of the review is to present an overview of the progress made in MS-based analysis of milk, and suggest a multi-pronged MS strategy to better explore different milk components for translational and clinical utilities.