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The renal system consists of the kidney, ureters, and the urethra. The overall function of the system filters approximately 200 liters of fluid a day from renal blood flow which allows for toxins, metabolic waste products, and excess ion to be excreted while keeping essential substances in the blood. The kidney regulates plasma osmolarity by modulating the amount of water, solutes, and electrolytes in the blood. It ensures long term acid-base balance and also produces erythropoietin which stimulates the production of red blood cell. It also produces renin for blood pressure regulation and carries out the conversion of vitamin D to its active form. The renal development, the process of urine production and excretion, and the clinical significance of the renal system will be the focus of this article.

EJIFCC. 2019 Mar 1;30(1):59–66.

Meeting Report on the IX European Symposium on Clinical Laboratory and In Vitro Diagnostics Industry (Barcelona)
The IX European Symposium of the Clinical Laboratory and In Vitro Diagnostics Industry, entitled “Stat Tests in Clinical laboratory”, took place in Barcelona, Catalonia (Spain), between May 17–18, 2017.

The scientific program was structured in several round-tables that dealt with the following topics: emergency laboratory models, accreditation of stat tests by ISO 15189, critical issues of stat tests and the new proposals of the in vitro diagnostics industry for emergency laboratories. The aim of the Symposium was the discussion of the transformation that stat tests have generated on clinical laboratories in terms of organization, turnaround time, accreditation, and probable evolution of these laboratories coming years.

Clin Kidney J. 2023 Jan 24;16(6):952–964

Hypertension is one of the major health problems leading to the development of cardiovascular diseases. Despite a rapid expansion in global hypertension prevalence, molecular mechanisms leading to hypertension are not fully understood largely due to the complexity of pathogenesis involving several factors. Salt intake is recognized as a leading determinant of blood pressure, since reduced dietary salt intake is related to lower morbidity and mortality, and hypertension in relation to cardiovascular events. Compared with salt-resistant populations, salt-sensitive individuals exhibit high sensitivity in blood pressure responses according to changes in salt intake. In this setting, the kidney plays a major role in the maintenance of blood pressure under the hormonal control of the renin–angiotensin–aldosterone system. In the present review, we summarize the current overview on the molecular mechanisms for modulation of blood pressure associated with renal ion channels/transporters including sodium–hydrogen exchanger isoform 3 (NHE3), Na+-K+-2Cl– cotransporter (NKCC2), sodium–chloride cotransporter (NCC), epithelial sodium channel (ENaC) and pendrin expressed in different nephron segments. In particular, recent studies on experimental animal models with deletion of renal ion channels led to the identification of several crucial physiological mechanisms and molecules involved in hypertension. These findings could further provide a potential for novel therapeutic approaches applicable on human patients with hypertension.

Clin J Am Soc Nephrol. 2015 Jan 28;10(2):305–324.

Intercalated cells are kidney tubule epithelial cells with important roles in the regulation of acid-base homeostasis. However, in recent years the understanding of the function of the intercalated cell has become greatly enhanced and has shaped a new model for how the distal segments of the kidney tubule integrate salt and water reabsorption, potassium homeostasis, and acid-base status. These cells appear in the late distal convoluted tubule or in the connecting segment, depending on the species. They are most abundant in the collecting duct, where they can be detected all the way from the cortex to the initial part of the inner medulla. Intercalated cells are interspersed among the more numerous segment-specific principal cells. There are three types of intercalated cells, each having distinct structures and expressing different ensembles of transport proteins that translate into very different functions in the processing of the urine. This review includes recent findings on how intercalated cells regulate their intracellular milieu and contribute to acid-base regulation and sodium, chloride, and potassium homeostasis, thus highlighting their potential role as targets for the treatment of hypertension. Their novel regulation by paracrine signals in the collecting duct is also discussed. Finally, this article addresses their role as part of the innate immune system of the kidney tubule.

The adult bone is continuously being remodelled to repair microdamage, preserve bone strength and mechanical competence as well as maintain calcium homeostasis. Bone turnover markers are products of osteoblasts (bone formation markers) and osteoclasts (bone resorption markers) providing a dynamic assessment of remodelling (turnover). Resorption-specific bone turnover markers are typically degradation products of bone collagen molecules (N- [NTX] and C-telopeptide cross-linked type 1 collagen [CTX]), which are released into the circulation and excreted in urine; or enzymatic activities reflecting osteoclastic resorption, tartrate-resistant acid phosphatase [TRACP]. Formation-specific bone turnover markers embrace different osteoblastic activities: type 1 collagen synthesis (Procollagen type I N- propeptide [PINP]), osteoblast enzymes (bone-specific alkaline phosphatase [BALP]), or bone matrix proteins [osteocalcin]. Among individuals not receiving osteoporosis treatment, resorption and formation markers are tightly linked and highly correlated (r = 0.6–0.8). Significant biological variability was reported in the past, but these issues have been greatly improved with automated assays and attention to pre-analytical and analytical factors that are known to influence bone turnover marker levels. Bone turnover markers are not useful in the diagnosis of osteoporosis, the individual prediction of bone loss, fracture, or rare complications, or in the selection of pharmacological treatment. Despite remaining issues with reference intervals and assays harmonization, bone turnover markers have proven to be useful in elucidating the pharmacodynamics and effectiveness of osteoporosis medications in clinical trials. As an alternative to BMD testing, BTMs may be useful to monitor osteoporosis therapies.

Angelo D’Alessandro, Alkmini T. Anastasiadi, Vassilis L. Tzounakas, Travis Nemkov, Julie A. Reisz, Anastsios G. Kriebardis, James C. Zimring, Steven L. Spitalnik and Michael P. Busch

Metabolites 2023, 13(7), 793 Full text için tıklayınız

Red blood cells (RBC) are the most abundant cell in the human body, with a central role in oxygen transport and its delivery to tissues. However, omics technologies recently revealed the unanticipated complexity of the RBC proteome and metabolome, paving the way for a reinterpretation of the mechanisms by which RBC metabolism regulates systems biology beyond oxygen transport. The new data and analytical tools also informed the dissection of the changes that RBCs undergo during refrigerated storage under blood bank conditions, a logistic necessity that makes >100 million units available for life-saving transfusions every year worldwide. In this narrative review, we summarize the last decade of advances in the field of RBC metabolism in vivo and in the blood bank in vitro, a narrative largely influenced by the authors’ own journeys in this field. We hope that this review will stimulate further research in this interesting and medically important area or, at least, serve as a testament to our fascination with this simple, yet complex, cell.

nherited disorders of hyperbilirubinemia may be caused by increased bilirubin production or decreased bilirubin clearance. Reduced hepatic bilirubin clearance can be due to defective (i) unconjugated bilirubin uptake and intrahepatic storage, (ii) conjugation of glucuronic acid to bilirubin (e.g., Gilbert syndrome, Crigler–Najjar syndrome, Lucey–Driscoll syndrome, breast milk jaundice), (iii) bilirubin excretion into bile (Dubin–Johnson syndrome), or (iv) conjugated bilirubin re-uptake (Rotor syndrome). In this review, the molecular mechanisms and clinical manifestations of these conditions are described, as well as current approaches to diagnosis and therapy.

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“Canlı organizmalar, cansız moleküllerden oluşmuşlardır. Bu moleküllerin, cansız maddelerin uymak zorunda oldukları tüm fiziksel ve kimyasal kurallara uydukları görülür. Ancak yaşayan organizmalar, cansız madde topluluklarının sahip olmadıkları üstün özelliklere sahiptir. İşte bu özellikleri incelemek ve nedenlerini araştırmak biyokimya ilminin konusudur. Biyokimyager ise, canlıların kimyasal yapı ve davranışlarını, kimyasal, fiziksel ve biyolojik yöntemler kullanarak araştıran bir bilim adamıdır.”

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Türk Biyokimya Derneği (TBD) Akademi olarak, yukarıda verilen bilgilerin ışığında ve devam eden tartışmaları dışlamadan, tüm meslektaşlarımızın ve eğiticilerin YZ okuryazarı olmalarını ve alanla ilgili bazı yetkinlikleri kazanmalarını önemsiyoruz. Bu belge de, eğiticilere bu yeni mecra konusunda farkındalık sağlamak ve YZ araçlarının eğitim ve öğrenmeyi iyileştirmek amacıyla nasıl kullanılabileceği konusunda temel bazı örnekler sunmak için hazırlanmış r. Bununla birlikte çok hızlı gelişen bir alan olması nedeniyle, tüm eği cilerin güncellemeleri ve alanla ilgili değişimleri yakından takip etmelerini de öneriyoruz. Bu belgenin en yaygın kullanılan üretici YZ araçlarının başında gelen ChatGPT’nin son ücretsiz sürümü olan GPT-3.5’i temel aldığı göz önünde bulundurulmalıdır. Ana amaçlarımızdan biri de 2023-2024 akademik yılı başında bu konuya dikkat çekmek ve eği cilere ders yılı başında ve sonrasında uygulayabilecekleri bazı önerilerde bulunarak bir yol haritası sunmaktır.

Clinicians are required to assess abnormal liver chemistries on a daily basis. The most common liver chemistries ordered are serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase and bilirubin. These tests should be termed liver chemistries or liver tests. Hepatocellular injury is defined as disproportionate elevation of AST and ALT levels compared with alkaline phosphatase levels. Cholestatic injury is defined as disproportionate elevation of alkaline phosphatase level as compared with AST and ALT levels. The majority of bilirubin circulates as unconjugated bilirubin and an elevated conjugated bilirubin implies hepatocellular disease or cholestasis. Multiple studies have demonstrated that the presence of an elevated ALT has been associated with increased liver-related mortality. A true healthy normal ALT level ranges from 29 to 33 IU/l for males, 19 to 25 IU/l for females and levels above this should be assessed. The degree of elevation of ALT and or AST in the clinical setting helps guide the evaluation. The evaluation of hepatocellular injury includes testing for viral hepatitis A, B, and C, assessment for nonalcoholic fatty liver disease and alcoholic liver disease, screening for hereditary hemochromatosis, autoimmune hepatitis, Wilson’s disease, and alpha-1 antitrypsin deficiency. In addition, a history of prescribed and over-the-counter medicines should be sought. For the evaluation of an alkaline phosphatase elevation determined to be of hepatic origin, testing for primary biliary cholangitis and primary sclerosing cholangitis should be undertaken. Total bilirubin elevation can occur in either cholestatic or hepatocellular diseases. Elevated total serum bilirubin levels should be fractionated to direct and indirect bilirubin fractions and an elevated serum conjugated bilirubin implies hepatocellular disease or biliary obstruction in most settings. A liver biopsy may be considered when serologic testing and imaging fails to elucidate a diagnosis, to stage a condition, or when multiple diagnoses are possible.

Laboratory liver tests are broadly defined as tests useful in the evaluation and treatment of patients with hepatic dysfunction. The liver carries out metabolism of carbohydrate, protein and fats. Some of the enzymes and the end products of the metabolic pathway which are very sensitive for the abnormality occurred may be considered as biochemical marker of liver dysfunction. Some of the biochemical markers such as serum bilirubin, alanine amino transferase, aspartate amino transferase, ratio of aminotransferases, alkaline phosphatase, gamma glutamyl transferase, 5′ nucleotidase, ceruloplasmin, α-fetoprotein are considered in this article. An isolated or conjugated alteration of biochemical markers of liver damage in patients can challenge the clinicians during the diagnosis of disease related to liver directly or with some other organs. The term “liver chemistry tests” is a frequently used but poorly defined phrase that encompasses the numerous serum chemistries that can be assayed to assess hepatic function and/or injury.