Engineering amino acid uptake or catabolism promotes CAR T-cell adaption to the tumor environment.

Cancer cells take up amino acids from the extracellular space to drive cell proliferation and viability. Similar mechanisms are applied by immune cells, resulting in the competition between conventional T cells, or indeed chimeric antigen receptor (CAR) T cells and tumor cells, for the limited availability of amino acids within the environment. We demonstrate that T cells can be re-engineered to express SLC7A5 or SLC7A11 transmembrane amino acid transporters alongside CARs.

Proline synthesis through PYCR1 is required to support cancer cell proliferation and survival in oxygen-limiting conditions.

The demands of cancer cell proliferation alongside an inadequate angiogenic response lead to insufficient oxygen availability in the tumor microenvironment. Within the mitochondria, oxygen is the major electron acceptor for NADH, with the result that the reducing potential produced through tricarboxylic acid (TCA) cycle activity and mitochondrial respiration are functionally linked. As the oxidizing activity of the TCA cycle is required for efficient synthesis of anabolic precursors, tumoral hypoxia could lead to a cessation of proliferation without another means of correcting the redox imbalance.

Proline metabolism and redox; maintaining a balance in health and disease.

Proline is a non-essential amino acid with key roles in protein structure/function and maintenance of cellular redox homeostasis. It is available from dietary sources, generated de novo within cells, and released from protein structures; a noteworthy source being collagen. Its catabolism within cells can generate ATP and reactive oxygen species (ROS).

Loss of SDHB Promotes Dysregulated Iron Homeostasis, Oxidative Stress, and Sensitivity to Ascorbate.

Succinate dehydrogenase is a key enzyme in the tricarboxylic acid cycle and the electron transport chain. All four subunits of succinate dehydrogenase are tumor suppressor genes predisposing to paraganglioma, but only mutations in the SDHB subunit are associated with increased risk of metastasis. Here we generated an knockout chromaffin cell line and compared it with deficient cells.

Succinate dehydrogenase deficiency in a chromaffin cell model retains metabolic fitness through the maintenance of mitochondrial NADH oxidoreductase function.

Mutations in succinate dehydrogenase (SDH) lead to the development of tumors in a restricted subset of cell types, including chromaffin cells and paraganglia. The molecular basis for this specificity is currently unknown. We show that loss of SDH activity in a chromaffin cell model does not perturb complex I function, retaining the ability to oxidize NADH within the electron transport chain.

New aspects of amino acid metabolism in cancer.

An abundant supply of amino acids is important for cancers to sustain their proliferative drive. Alongside their direct role as substrates for protein synthesis, they can have roles in energy generation, driving the synthesis of nucleosides and maintenance of cellular redox homoeostasis. As cancer cells exist within a complex and often nutrient-poor microenvironment, they sometimes exist as part of a metabolic community, forming relationships that can be both symbiotic and parasitic.

Professional levels in relation to the needs and to self-education abilities. A pedagogy for continuining medical education.

The pedagogical peculiarities of continuing medical education (CME) essentially lie in the fact that it is addressed to adult subjects with their personal style of learning and showing a disposition to autonomous learning. Therefore CME cannot be limited to educational and training approaches but should be aimed at education and training. To be effective, CME must privilege interactive teaching methodologies.

[Assessment of clinical competence of medical school graduates in Italy with standardized patients. The opinion of the examinees].

An international collaborative project for the evaluation of clinical competence at the end of the Medical School curriculum using the ECFMG-CSA (Educational Commission for Foreign Medical Graduates--Clinical Skills Assessment) prototype was started in Italy in April 1996. Faculty representatives from Italian Medical Schools and experts from the ECFMG in Philadelphia participated in the Project. The CSA consists of integrated clinical encounters with 10 standardized patients during which the examinee is asked to obtain a focused history, perform a relevant physical examination and communicate initial diagnoses and management plan to the Standardized Patient (SP).

Abnormalities of membrane protein composition in patients with autoimmune haemolytic anaemia.

Acquired abnormalities of red cell membrane protein composition in 37 patients with a positive direct antiglobulin test have been studied: 17 patients had true autoimmune haemolytic anaemia and 20 were HIV-infected subjects with a positive direct antiglobulin test but without signs of haemolysis. The study was carried out by performing sodium dodecyl sulphate polyacrylamide gel electrophoresis of ghost proteins followed by densitometric evaluation of the areas under the peaks, normalized by the total (alpha + beta) spectrin content. Results show a significant decrease of bands 3, 4.

In vitro proteolysis of the red cell membrane in patients with HIV infection.

It has been suggested that acquired abnormalities of the red cell membrane due to various injuries [azidothymidine (AZT) therapy, immunoglobulin coating of red cells, differentiation abnormalities of erythroid precursors] contribute to the onset of anaemia in HIV-infected patients. In vitro proteolysis of erythrocyte membrane proteins is regarded as a molecular marker of membrane damage induced in vivo by different agents. We therefore investigated in vitro proteolysis of ghosts derived from red blood cells of 30 HIV-infected patients.

Activation of K+/Cl- cotransport in human erythrocytes exposed to oxidative agents.

Activation of K+/Cl- cotransport was studied after exposure of normal human erythrocytes to the oxidative action of acetylphenylhydrazine (APH), menadione sodium bisulfite (MSB), hydrogen peroxide (H2O2) or phenazine metasulfate (PMS). In order to better define the relative contributions of K+/Cl- cotransport on ouabain and bumetanide-resistant (OBR) K+ efflux induced by oxidation, we used (dihydroindenyl)oxyalkanoic acid (DIOA) and carbocyanine as specific inhibitors, respectively, of cotransport system and Ca(2+)-activated K+ channel. APH, MSB and - to much less extent - H2O2 promoted a K+ efflux pathway with features corresponding to those of K+/Cl- cotransport.

Role of spleen in hereditary spherocytosis: evidence for increased in vitro proteolysis of red cell membrane.

In vitro proteolysis of red cell membranes has been studied by means of electrophoretic separation on SDS-polyacrylamide gel of solubilized ghost proteins and subsequent densitometry of separated, stained bands; the amounts of major membrane proteins were measured in ghosts either with inhibited or with allowed proteolysis in the following cases: 15 patients suffering from hereditary spherocytosis (HS) with variable degree of spleen enlargement, eight cirrhotic patients with spleen enlargement and 12 healthy blood donors as control group. Proteolysis was present to a greater extent in HS patients with larger splenomegaly, lesser in HS with smaller splenomegaly, and was comparable to healthy controls both in splenectomized HS and in patients with spleen enlargement due to liver cirrhosis. The results suggest the involvement of splenomegaly in the enhancement of in vitro proteolysis in HS red cell membrane; it is probably attributable to joint effects of the damage induced in red cells by prolonged retention within haemolysing spleen together with the abnormalities genetically affecting the structure of HS red cell membrane.

Diagnostic and therapeutic problems in a case of adrenal tuberculosis and acute Addison's disease.

A case of adrenal tuberculosis with acute Addison's disease is presented. The case showed diagnostic and therapeutic problems, the latter concerning the untoward effects due to metabolic interferences and pharmacologic interactions among antitubercular drugs, substitutive corticosteroid therapy and hepatic metabolism. The side-effects, interactions and metabolism of drugs used during the course of disease are discussed.

Erythrocyte endogenous proteinase activity during blood bank storage.

We studied proteolytic alterations of membrane proteins in ghosts derived from human red blood cells, preserved up to 35 days in the liquid state either as whole blood or with additive solution. The study was carried out by performing sodium dodecyl sulfate polyacrylamide gel electrophoresis of stromal proteins from erythrocytes, either previously treated with proteinase inhibitors or previously incubated in conditions promoting proteolysis. To differentiate the effect of erythrocyte from granulocyte proteinases, the investigation was also carried out in leukocyte-free red cell preparations.

Increased proteolytic activity of erythrocyte membrane in spur cell anaemia.

In a case of 'spur cell anaemia' (SCA) a reduced esterified/free cholesterol ratio was found in plasma, in LDL and HDL fractions and an increased cholesterol/phospholipid (C/PL) molar ratio in erythrocyte membrane. Cation transport was normal with the exception of Li-Na counter-transport was decreased. An increased intrinsic membrane proteolytic activity (IMPA) was demonstrated by the generalized reduction or, sometimes, disappearance of protein bands on SDS-PAGE in patient ghosts when the proteolysis was allowed.

Determination of neutral haemoglobin variants by immobilized pH gradient, reversed-phase high-performance liquid chromatography and fast-atom bombardment mass spectrometry: the case of a Hb Torino alpha 43 (CE1) Phe----Val.

A neutral haemoglobin variant was identified by the combined use of different analytical methods. Isoelectric focusing on immobilized pH gradients (under denaturing conditions) allowed to detect and alpha chain variant. HPLC of tryptic digest showed that its amino-acid variation resided on T alpha 6 peptide (position 41-56).

Effects of lead on red blood cell membrane proteins.

The effects of lead on red blood cell (RBC) membrane proteins were studied in two groups of workers with different lead exposure levels: Group I (6 subjects employed in a battery plant) with a mean blood lead of 40.1 (SD = 3.7) micrograms/100 ml; Group II (5 workers employed in different industries) with a mean blood lead of 60.

A benign form of thalassaemia intermedia may be determined by the interaction of triplicated alpha locus and heterozygous beta-thalassaemia.

In this paper we report that the combination of a triplicated alpha globin locus with heterozygous beta-thalassaemia produces a clinical phenotype of thalassaemia intermedia in five Italian subjects from four unrelated families, while in two other cases the phenotype was thalassaemia minor. The haematological findings of the five patients were uniform, producing a benign form of thalassaemia intermedia, transfusion independent, with a long life expectancy. The pattern of inheritance of the two genetic determinants and the more pronounced beta/alpha globin chain imbalance, demonstrates that the genetic combination is indeed the cause of the phenotype.