I first read Davidson 30 years ago: at that time it was already in its 5th edition. A brief comparison shows that it then contained about 440,000 words in 1,100 pages: the current edition has compressed 625,000 words into 800 pages. I think I bought it as a student because it was cheap: but also because it seemed to be comprehensive and straightforward, and I have used it as a basis for my medical knowledge ever since. So I miss some of the old pictures of the acute skin rashes such as scarlet fever: in fact infectious disease has been transferred to the back and genetic factors take the first chapters. But careful linguistic comparison will still uncover the old phrases which some of us know by heart-there are minor changes such as 'alarming reactions to intravenous iron are uncommon, but have occasionally been noted', which becomes 'alarming systemic anaphyllactic reactions can occur'. Sir Stanley Davidson made 'no attempt to describe every rare disease or syndrome, but devoted most of the space available to those disorders most commonly encountered in practice'. I have grown up with successive editions, and have gradually come to appreciate the problems of the authors in the compression of knowledge. Having got to know many of them personally as real people rather than as names I can still recommend the book. It is the essential starting point for the study of internal medicine and for many doctors will remain their base reference work. The present editors have kept up-to-date and been prepared to prune the dead wood. There are many competitors in the market, and the publishers must take care with layout and illustration, although Davidson is still the best value for money. I will continue to recommend it to my clinical students: they will need to read it and know it to pass final MB. Postgraduates will need to remember the facts, but also to be able to place them in a broader perspective. The older consultant will still happily read it, and to get to know the authors themselves is really to complete your medical education. Dr John Macleod and his team have successfully kept alive the primary objective 'to provide a rational and easily comprehensible basis for the practice of medicine'. The book is economical in price and compact in size, but still contains the essential truths for the practice of good medicine.

Davidson's Principles and Practice of Medicine

The marine environment represents a relatively untapped source of functional ingredients that can be applied to various aspects of food processing, storage, and fortification. Moreover, numerous marine-based compounds have been identified as having diverse biological activities, with some reported to interfere with the pathogenesis of diseases. Bioactive peptides isolated from fish protein hydrolysates as well as algal fucans, galactans and alginates have been shown to possess anticoagulant, anticancer and hypocholesterolemic activities. Additionally, fish oils and marine bacteria are excellent sources of omega-3 fatty acids, while crustaceans and seaweeds contain powerful antioxidants such as carotenoids and phenolic compounds. On the basis of their bioactive properties, this review focuses on the potential use of marine-derived compounds as functional food ingredients for health maintenance and the prevention of chronic diseases.

https://www.mdpi.com/1660-3397/9/6/1056/pdf

Marine Bioactives as Functional Food Ingredients: Potential to Reduce the Incidence of Chronic Diseases

Natural bioactive compounds include a broad diversity of structures and functionalities that provide an excellent pool of molecules for the production of nutraceuticals, functional foods, and food additives. Some of those compounds can be found in nature at high concentration such as polyphenols but others can only be found at very low levels, so that massive harvesting is needed to obtain sufficient amounts, and their structural diversity and complexity make chemical synthesis unprofitable. The inherent difficulties in screening and producing these compounds have led to the development of advanced technologies. The commonly used methods for their extraction are the conventional liquid–liquid or solid–liquid extraction and the advanced include pressurized-liquid extraction, subcritical and supercritical extractions, and microwave- and ultrasound-assisted extractions. In addition, these extraction techniques have been improved with previous steps (enzyme-and instant controlled pressure drop-assisted extractions) which help to release the compounds from the matrix. These technologies could provide in the next few years an innovative approach to increase the production of specific compounds for use as nutraceuticals or as ingredients in the design of functional foods.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1541-4337.12005

Technologies for Extraction and Production of Bioactive Compounds to be Used as Nutraceuticals and Food Ingredients: An Overview

The synthesis of nanoparticles has become a matter of great interest in recent times due to their various advantageous properties and applications in a variety of fields. The exploitation of different plant materials for the biosynthesis of nanoparticles is considered a green technology because it does not involve any harmful chemicals. In this study, iron oxide nanoparticles (Fe3O4-NPs) were synthesized using a rapid, single step and completely green biosynthetic method by reduction of ferric chloride solution with brown seaweed (BS, Sargassum muticum) water extract containing sulphated polysaccharides as a main factor which acts as reducing agent and efficient stabilizer. The structural and properties of the Fe3O4-NPs were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive X-ray fluorescence spectrometry (EDXRF), vibrating sample magnetometry (VSM) and transmission electron microscopy. The average particle diameter as determined by TEM was found to be 18 ± 4 nm. X-ray diffraction showed that the nanoparticles are crystalline in nature, with a cubic shape. The nanoparticles synthesized through this biosynthesis method can potentially useful in various applications.

https://www.mdpi.com/1420-3049/18/5/5954/pdf

Green biosynthesis and characterization of magnetic iron oxide (Fe₃O₄) nanoparticles using seaweed (Sargassum muticum) aqueous extract.

The last edition of Tietz's Fundamentals of Clinical Chemistry appeared more than ten years ago and survives as a dated but valuable reference. The successor to Fundamentals, Textbook of Clinical Chemistry , follows an outline similar to the original text but adds many new subjects and updates older topics. This has resulted in a text that is 50% larger than its predecessor. Much of the newer material centers on interpretation and understanding of data and its limitations. For example, more than 200 pages (compared with 50 pages) are dedicated to an introductory section entitled "Acquisition, Management, and Application of Laboratory Data," covering the use of reference ranges, statistics, quality assurance, method evaluation, and computers. The remaining introductory chapters discuss general procedures, instrumentation, and automation. Unfortunately, the chapter that discusses current automated instrumentation already has been outdated by equipment evolution and could have been incorporated into the chapter about general instrumentation principles.

Textbook of Clinical Chemistry

Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. Algae can be classified into two main groups; first one is the microalgae, which includes blue green algae, dinoflagellates, bacillariophyta (diatoms)… etc., and second one is macroalgae (seaweeds) which includes green, brown and red algae. The microalgae phyla have been recognized to provide chemical and pharmacological novelty and diversity. Moreover, microalgae are considered as the actual producers of some highly bioactive compounds found in marine resources. Red algae are considered as the most important source of many biologically active metabolites in comparison to other algal classes. Seaweeds are used for great number of application by man. The principal use of seaweeds as a source of human food and as a source of gums (phycocollides). Phycocolloides like agar agar, alginic acid and carrageenan are primarily constituents of brown and red algal cell walls and are widely used in industry.

Biological importance of marine algae.

The present investigation was designed to investigate the protective effect of (Beta vulgaris L.) beat root ethanolic extract (BVEE) on gentamicin-induced nephrotoxicity and to elucidate the potential mechanism. Serum specific kidney function parameters (urea, uric acid, total protein, creatinine, and histopathology of kidney tissue) were evaluated to access gentamicin-induced nephrotoxicity. The oxidative/nitrosative stress (Lipid peroxidation, MDA, NP-SH, Catalase, and nitric oxide levels) was assessed. The inflammatory response (TNF-α, IL-6, MPO, NF-κB (p65), and NF-κB (p65) DNA binding) and apoptotic marker (Caspase-3, Bax, and Bcl-2) were also evaluated. BVEE (250 and 500 mg/kg) treatment along with gentamicin restored/increased the renal endogenous antioxidant status. Gentamicin-induced increased renal inflammatory cytokines (TNF-α and IL-6), nuclear protein expression of NF-κB (p65), NF-κB-DNA binding activity, myeloperoxidase (MPO) activity, and nitric oxide level were significantly down regulated upon BVEE treatment. In addition, BVEE treatment significantly reduced the amount of cleaved caspase 3 and Bax, protein expression and increased the Bcl-2 protein expression. BVEE treatment also ameliorated the extent of histologic injury and reduced inflammatory infiltration in renal tubules. These findings suggest that BVEE treatment attenuates renal dysfunction and structural damage through the reduction of oxidative stress, inflammation, and apoptosis in the kidney.

/pdf/beetroot-beta-vulgaris-l-extract-ameliorates-gentamicin-2wh3f142fp.pdf

Beetroot (Beta vulgaris L.) extract ameliorates gentamicin-induced nephrotoxicity associated oxidative stress, inflammation, and apoptosis in rodent model.

Five xanthone derivatives and one flavanol were isolated from the dichloromethane extract of Garcinia mangostana. Dichloromethane, ethyl acetate extract and the major xanthone (α-mangostin) were evaluated in vitro against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. The major constituent α-mangostin was also checked for antimicrobial potential against Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Bacillius subtilis, Staphylococcus aureus, Mycobacterium smegmatis, M. cheleneoi, M. xenopi and M. intracellulare. Activity against P. falciparum (IC50 2.7 μg/mL) and T. brucei (IC50 0.5 μg/mL) were observed for the dichloromethane extract, however, with only moderate selectivity was seen based on a parallel cytotoxicity evaluation on MRC-5 cells (IC50 9.4 μg/mL). The ethyl acetate extract was inactive (IC50 > 30 µg/mL). The major constituent α-mangostin showed rather high cytotoxicity (IC50 7.5 µM) and a broad but non-selective antiprotozoal and antimicrobial activity profile. This in vitro study endorses that the antiprotozoal and antimicrobial potential of prenylated xanthones is non-conclusive in view of the low level of selectivity.

https://www.mdpi.com/1420-3049/18/9/10599/pdf

Phytochemical, antimicrobial and antiprotozoal evaluation of Garcinia mangostana pericarp and α-mangostin, its major xanthone derivative.

Background: The present study reports and compares the results of Gas Chromatographic-Mass analyses of Pulicaria jaubertii leaf (P-1) and root (P-2) essential oils, as well as their in vitro antimicrobial and cytotoxic activities. Materials and Methods: The chemical composition of P-1 and P-2 essential oils of P. jaubertii, was investigated by GC-MS. Moreover, the essential oils were evaluated for their antimicrobial activity using the broth micro-dilution assay for minimum inhibitory concentrations (MIC). The crystal violet staining method (CVS) was used for evaluation of their cytotoxic activity on HEPG-2 and MCF-7 human cell lines. Results: This investigation led to the identification of 16 constituents in P-1 , and 23 constituents in P-2 , representing 99.92% and 94.74% of the oils respectively. Oxygenated monoterpenes were found to be the major group in both P-1 (99.47%) and P-2 (89.88%). P-1 consists almost entirely of p-Menth-6-en-2-one (Carvotanacetone, 98.59%). P-2 is characterized by high contents of each of Dimethoxydurene (38.48%), Durenol (26.89%) and 2′,4Ͳ-Dimethoxy-3′-methylacetophenone (20.52%). Both oils showed moderate antimicrobial activity against the Gram-positive strains and C. albicans. However, no activity was shown against Gram-negative bacteria. P-1 showed a significant cytotoxic activity against both MCF-7 and HEPG-2 (IC 50 = 3.8 and 5.1 μg/ml, respectively), while P-2 showed selective cytotoxic activity against MCF-7 cell line (IC 50 = 9.3 μg/ml). Conclusion: The potent cytotoxic and moderate antimicrobial activities of P-1 may be attributed to its high content of Carvotanacetone.

Chemical composition and biological evaluation of essential oils of Pulicaria jaubertii.

Two lupane and four ursane triterpenes, namely epilupeol (1), lupeol acetate (2), ursolic acid (3), brein (4), 3β 11α-dihydroxy urs-12-ene (5) and ursolic acid lactone (6) were isolated from aerial parts of Kleinia odora and identified. Compounds 1 and 3-6 were isolated for the first time from K. odora. The triterpene constituents were investigated for antiprotozoal potential against erythrocytic schizonts of Plasmodium falciparum, intracellular amastigotes of Leishmania infantum and Trypanosoma cruzi and free trypomastigotes of T. brucei. Cytotoxicity was determined against MRC-5 fibroblasts to assess selectivity. The ursane triterpenes were found to be active against more than one type of the tested parasites, with the exception of compound 6. This is also the first report on the occurrence of ursane type triterpenes in the genus Kleinia and their antiprotozoal potential against P. falciparum, L. infantum, T. cruzi, and T. brucei.

https://www.mdpi.com/1420-3049/18/8/9207/pdf

Ali A. El Gamal

Papers

Biological importance of marine algae.

Beetroot (Beta vulgaris L.) extract ameliorates gentamicin-induced nephrotoxicity associated oxidative stress, inflammation, and apoptosis in rodent model.

Phytochemical, antimicrobial and antiprotozoal evaluation of Garcinia mangostana pericarp and α-mangostin, its major xanthone derivative.

Chemical composition and biological evaluation of essential oils of Pulicaria jaubertii.

In vitro antiprotozoal activity of triterpenoid constituents of Kleinia odora growing in Saudi Arabia.