Metaraminol uptake by human thrombocytes: A poor model for neuronal noradrenaline uptake

Summary The IC₅₀ of a number of antidepressants and related drugs on the uptake of 1-metaraminol and serotonin into human thrombocytes, and of noradrenaline and serotonin into rat midbrain synaptosomes were compared. In accordance with previous reports, it was found that platelets, provide a good model for the study of neuronal uptake of serotonin. Platelet uptake of 1-metaraminol, although correlated to some extent with noradrenaline uptake into synaptosomes, seems to be an unsatisfactory model for the neuronal uptake of the latter amine.     

Molecular dialogue between the human gut microbiota and the host: a Lactobacillus and Bifidobacterium perspective

The human gut represents a highly complex ecosystem, which is densely colonized by a myriad of microorganisms that influence the physiology, immune function and health status of the host. Among the many members of the human gut microbiota, there are microorganisms that have co-evolved with their host and that are believed to exert health-promoting or probiotic effects. Probiotic bacteria isolated from the gut and other environments are commercially exploited, and although there is a growing list of health benefits provided by the consumption of such probiotics, their precise mechanisms of action have essentially remained elusive. Genomics approaches have provided exciting new opportunities for the identification of probiotic effector molecules that elicit specific responses to influence the physiology and immune function of their human host. In this review, we describe the current understanding of the intriguing relationships that exist between the human gut and key members of the gut microbiota such as bifidobacteria and lactobacilli, discussed here as prototypical groups of probiotic microorganisms.     

Adenosine uptake in pyrimidine 5'-nucleotidase deficient human erythrocytes via a high affinity transport system

Using a pulse-labeling technique, 14C-adenosine uptake into pyrimidine 5'-nucleotidase (P5N) deficient erythrocytes (RBC) was found to be impaired. The Lineweaver-Burk plot showed Km values of 2.0 X 10(-3) mM and 0.2 X 10(-3) mM for normal RBC and P5N deficient RBC, respectively. These results indicate that P5N is one of regulators of the adenosine transport system and/or is associated with adenosine carrier protein.     

The human leukemia cell line, THP-1: a multifacetted model for the study of monocyte-macrophage differentiation

THP-1 is a human monocytic leukemia cell line. After treatment with phorbol esters, THP-1 cells differentiate into macrophage-like cells which mimic native monocyte-derived macrophages in several respects. Compared to other human myeloid cell lines, such as HL-60, U937, KG-1, or HEL cell lines, differentiated THP-1 cells behave more like native monocyte-derived macrophages. Because of these characteristics, the THP-1 cell line provides a valuable model for studying the mechanisms involved in macrophage differentiation, and for exploring the regulation of macrophage-specific genes as they relate to physiological functions displayed by these cells.     

Familial hemophagocytic lymphohistiocytosis: a model for understanding the human machinery of cellular cytotoxicity

Cytotoxic T lymphocytes, natural killer cells, and NKT cells are effector cells able to kill infected cells. In some inherited human disorders, a defect in selected proteins involved in the cellular cytotoxicity mechanism results in specific clinical syndromes, grouped under the name of familial hemophagocytic lymphohistiocytosis. Recent advances in genetic studies of these patients has allowed the identification of different genetic subsets. Additional genetic immune deficiencies may also induce a similar clinical picture. International cooperation and prospective trials resulted in refining the diagnostic and therapeutic approach to these rare diseases with improved outcome but also with improved knowledge of the mechanisms underlying granule-mediated cellular cytotoxicity in humans.     

The cyclic motor activity of the ovine gut: its reset at a faster rhythm

Summary In adult sheep, the frequency of the migrating motor complexes (MMC) was increased by the duodenal administration of methysergide, but not affected by other 5-HT₁ or 5-HT₂ antagonists. This reset of the MMC pattern at a faster rhythm suggests a selective action on the enteric neuronal serotoninergic mechanism modulating the pacing of the gut cyclic motor activity.     

Evidence for a different site of action of phenoxybenzamine and desmethylimipramine on the catecholamine uptake system

Resumen El tratamiento con fenoxibenzamina o desmetilimipramina da lugar a una potenciación irreversible de las respuestas a noradrenalina, en la aurícula aislada de cobayo. La presencia de tiramina durante el tratamiento previene dicha potenciación cuando se utiliza fenoxibenzamina, mientras que no la modifica en el caso de la desmetilimipramina     

Influence of coronary dilators on the uptake of serotonin by human platelets and adrenaline by chromaffine granules

Zusammenfassung In einer unspezifischen, physikalisch-chemischen Wirkung von vier oberflächenaktiven Coronardilatatoren auf die Membranen von menschlichen Thrombozyten und isolierten chromaffinen Granula wird die Ursache für die Hemmung der Aufnahme von Serotonin bzw. Adrenalin erblickt.     

The human leukemia cell line,THP-1: A multifacetted model for the study of monocyte-macrophage differentiation

Summary THP-1 is a human monocytic leukemia cell line. After treatment with phorbol esters, THP-1 cells differentiate into macrophage-like cells which mimic native monocyte-derived macrophages in several respects. Compared to other human myeloid cell lines, such as HL-60, U937, KG-1, or HEL cell lines, differentiated THP-1 cells behave more like native monocyte-derived macrophages. Because of these characteristics, the THP-1 cell line provides a valuable model for studying the mechanisms involved in macrophage differentiation, and for exploring the regulation of macrophage-specific genes as they relate to physiological functions displayed by these cells.     

Action and teleaction of specific ligands on DNA: a quantitative study with Azbel's model and an application to the regulatory mechanism of the lac operon]

Assuming that the action of specific ligands is transferred to DNA via the bases in close contact with the ligand, which are stabilized (or destablized) in this process, the local and more distant action of the ligand on DNA can be evaluated quantitatively with the aid of Azbel's model. An application to the system regulating the E. coli lac operon is presented.     

The Light Green Cells of Lymnaea: a neuroendocrine model system for stimulus-induced expression of multiple peptide genes in a single cell type.

We review recent experiments showing that the cerebral neuroendocrine Light Green Cells (LGCs) of the freshwater snail, Lymnaea stagnalis, express a family of distinct though related molluscan insulin-related peptide (MIP) genes. The LGCs are involved in the regulation of a wide range of interrelated life processes associated with growth, (energy) metabolism and reproduction. We consider the mechanism of generation of diversity among MIPs, and present evidence that conditions with distinct effects on growth, metabolism and reproduction also can induce distinct patterns of expression of the MIP and schistosomin genes. The stimulus-dependent expression of multiple neuropeptide genes enormously increases the adaptive potential of a peptidergic neuron. We suggest that this contributes significantly to the information-handling capacity of the brain.     

The influence of lethal X-irradiation on trace metal uptake by the mitochondrion

Zusammenfassung Die Aufnahme von Spurenmetallen durch Mitochondrien der Milz von Ratten, die letalen Dosen von Röntgenstrahlen ausgesetzt worden waren, wurde in vitro durch radioaktive Tracerisotope bestimmt. Kurz nach der Bestrahlung wurde bei Kobalt, Eisen, Nickel, Selen und Zink eine erhöhte, bei Chrom und Mangan eine verringerte Aufnahme beobachtet.