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PubMed2026

Biologic-biologic and biologic-JAK inhibitor combination therapy in refractory systemic autoinflammatory diseases.

OBJECTIVES: Systemic autoinflammatory diseases (SAIDs) arise from genetic defects in innate immunity, leading to dysregulated activation of inflammatory pathways, including interleukin (IL)-1, IL-6, TNF, and JAK/STAT. Clinical manifestations range from recurrent fever to severe complications such as encephalitis and AA amyloidosis. Management aims to control inflammation using immunosuppressive agents and targeted monotherapies (biologics or JAK inhibitors). Advanced combination therapy (ACT), defined as the use of biologics and/or JAK inhibitors in combination, has emerged as a strategy for refractory disease. METHODS: In this observational retrospective longitudinal cohort study, patients with SAIDs treated with ACT were included. Demographic, clinical, treatment, and safety data were collected. Treatment response was assessed using a composite outcome incorporating corticosteroid dose, C-reactive protein (CRP), and clinical improvement and categorized as non-response, partial response, or complete response. RESULTS: Thirty-eight patients (median age 30 years [range 4-76]) were included. The most common indications for ACT were pyogenic arthritis, pyoderma gangrenosum and acne (PAPA), mevalonate kinase deficiency (MKD), and undifferentiated SAIDs. Most patients had disease-related complications and were dependent on glucocorticoids and/or opioids to control inflammation and pain, respectively. Following multiple ACT trials, complete response was observed in 21 patients (55.3%), partial response in 12 (31.6%), and no response in 5 (13.1%). Overall, 65 ACT regimens were administered, most commonly combining IL-1 and TNF inhibitors. Thirty-nine regimens were discontinued because of lack of efficacy, secondary loss of response, or adverse events. At the final follow-up, 26 patients (68%) remained on ACT, with a median treatment duration of 60 months (range, 11-186). CONCLUSIONS: ACT offers significant clinical benefits for patients with difficult-to-treat SAIDs, though challenges such as secondary loss of efficacy and infection risks remain.

Humans↗

PubMed1977

Biological and immunological characterization of human luteinizing hormone: II. A comparison of the immunological and biological activities of pituitary extracts after electrofocusing using different standard preparations.

The profile of immunologically active human luteinizing hormone (hLH) was determined in aqueous pituitary extracts after electrofocusing using two radioimmunoassay systems and the estimates for each fraction were compared to those obtained by an in vitro bioassay method. Similar biological and immunological profiles were obtained in the pH 7.0-9.0 region, where most of the biological activity was present. Biological to immunological (B/I) ratios ranging from 0.6 to 1.7 (mean ratio 1.01; n = 21) were found in the major biologically active fractions of this pH region when a highly purified human pituitary LH preparation (68/40) was used as standard in both types of assays. The close proximity of these ratios to unity indicates a similar composition of biological and immunological activities in all these fractions in relation to that of the highly purified standard. However, marked discrepancies were observed in the pH region 3.0-7.0 where the B/I ratios ranged from 0.1 to 0.9, indicating the presence of immunological activity associated with relatively little biological activity. When impure human LH preparations of pituitary (69/104) and urinary (hMG 2nd IRP) origin were used as standards for the bioassay and radioimmunoassay of the hLH present in the major fractions of the pH region 7.0-9.0, significantly higher B/I ratios were obtained than with the use of the highly purified standard (68/40). These elevated B/I ratios are attributed to the presence in the impure standard preparations of immunological activity, which is associated with little or no biological activity. These observations may provide an explanation for the differences in B/I ratios which were reported for hLH in plasma, using different standard preparations.

Biological Assay↗

PubMed1978

Biological and immunological characterization of human luteinizing hormone: IV. Biological and immunological profile of two international reference preparations after electrofocusing.

The first IRP of Human Pituitary Gonadotrophins (FSH/LH) for bioassay (69/104) and the 1st IRP of Human Pituitary Luteinizing Hormone (LH) for immunoassay (68/40) were fractionated by an electrofocusing technique in a sucrose density gradient and the profile of biological and immunological activities was determined. The partially purified LH preparation (69/104) gave a broad pattern of biolgical and immunological activities which extended from pH 4 to 10. The biological : immunological (B/I) ratio of the various fractions (using the 68/40 preparation as standard) ranged from 0.04 to 1.05. The low B/I ratios indicate the presence of high levels of immunologically active, biologically inactive material in this preparation. In contrast to the behaviour of the 69/104 preparation, the major proportion (88%) of the biological activity recovered after electrofocusing of the highly purified LH preparation (68/40) was found within the pH range 7--9, with B/I ratios (again using as standard the 68/40 preparation) ranging from 0.4 to 1.5. Multiple dose parallel line design radioimmunoassays revealed a lack of parallelism between the 69/104 and 68/40 International Reference Preparations. This was attributed to the presence of acidic material in the former preparation, which is practically absent from the latter. The biological LH profiles of both the 69/104 and 68/40 preparations differed from those previously reported for aqueous extracts of pituitaries. It is concluded that the dissimilarity in the electrofocusing profiles of the biological and immunological activities of the 69/104 preparation renders this preparation unsuitable as a reference preparation for the quantitation of biologically active LH by radioimmunoassay methods. Using the same criteria, the 68/40 preparation would appear to be a more suitable standard.

Animals↗

PubMed1979

Biologically active luteinizing hormone (LH) in plasma. V. A re-analysis of the differences in the ratio of biological to immunological LH activities during the menstrual cycle.

The relationship between the biological and immunological activities of human luteinizing hormone (hLH) in plasma collected from female subjects was examined. The biological activity was measured by an in vitro bioassay and the immunological activity by an hLH radioimmunoassay (RIA), using improved reagents, such as the 1st IRP for human pituitary LH for immunoassay (code No. 68/40) as standard, a subunit-free biologically active iodinated hLH preparation as tracer and an anti-hLH serum of relatively high specificity. Similar profiles of biological (B) and immunological (I) activity were obtained in the plasma samples collected daily throughout 40 menstrual cycles (5 cycles from each of 8 subjects). However, the B/I ratios were significantly lower during the period of LH surge (P less than 0.001) than throughout the remainder of the cycle. The within- and between-assay variation in B/I ratios was investigated by the simultaneous assay of biological and immunological activities in plasma pools obtained by combining equal aliquots of plasma from each daily sample of the menstrual cycle from each of 5 cycles of each of 4 subjects. The analysis of these 20 pools revealed highly significant individual differences in B/I ratios, ranging from 0.81 to 1.33. The coefficient of variation was 20% between-subjects and 5% within-subjects. There was no seasonal variation in B/I ratios. That the individual differences in plasma B/I ratios were not attributable to the procedure of pooling was ascertained by the simultaneous assay of both activities in parellel in daily plasma samples and in the pools formed from these samples from three complete cycles. Thus the analysis of the differences in B/I ratios obtained throughout the menstrua- cycle revealed three major sources of variation. The first occurs in the form of generally elevated (higher than unity) B/I ratios, the second consists of a significant drop in B/I ratios during the midcycle LH surge, and the third source is represented by the significant between-subject differences. It is concluded that the first source is attributable to the relatively higher levels of "impurity" (i.e. biologically inactive, immunologically active material) in the standard preparation compared to those present in plasma of biologically inactive, immunologically active material of unknown composition and origin. If so, the latter source limits the quantitative significance of the RIA procedures employed. It is suggested that these three sources of variation account for most of the differences in B/I ratios for plasma lLH reported in the literature.

Adult↗

PubMed2026

Biological Parts in Yeast Synthetic Biology: From Regulatory Elements to Predictive Design Platforms.

Yeasts, particularly Saccharomyces cerevisiae, are important eukaryotic chassis for synthetic biology because of their tractable genetics, versatile toolkits, and broad utility in metabolic engineering and functional genomics. Progress in this field has been driven by biological parts that enable programmable control of gene expression and cellular behavior. Early efforts focused mainly on promoters, terminators, and other regulatory elements for tuning individual genes. However, as engineering expanded to multigene pathways, genetic circuits, and dynamic regulatory systems, the limits of part-centric design became clear. Part performance is often shaped by genomic context, chromatin state, host physiology, and interactions with other components, which restricts modularity and predictability. In response, yeast synthetic biology is shifting toward integrated design frameworks combining multilayer regulation, standardized assembly, automated experimentation, and computational modeling. This review provides an integrated perspective on the evolution of biological parts across DNA-, RNA-, and protein-level regulation, connecting these advances with assembly frameworks, biofoundries, and machine learning to trace the trajectory from part-centric engineering toward predictive, system-level design in yeast synthetic biology.

Biofoundry↗

PubMed1979

Physical plasma in biological solids: a possible mechanism for resonant interactions between low intensity microwaves and biological systems.

Observed semiconductor properties of biological material in vitro indicate possible involvement of semiconduction in biological processes. Since in inorganic semiconductors solid-state plasma occurs, it is hypothesized that in organic semiconductors solid-state plasma similarly occurs. Some results of experimental investigation of resonant effects of microwaves in biological systems are considered in the light of that hypothesis. The conditions necessary for the existence of physical plasma in biological solid structures are discussed, and certain parameters of physical plasma in these structures are evaluated. Its is proposed that microwave radiation may support or damp plasma oscillations, thereby stimulating or suppressing biological functions.

Biology↗

PubMed1979

The chemistry and biology of thymosin. I. Isolation, characterization, and biological activities of thymosin alpha1 and polypeptide beta1 from calf thymus.

A partially purified extract from thymus tissue termed thymosin Fraction 5 has been shown to reconstitute immunological deficiencies resulting from the lack of thymic function in several animal models, as well as humans with primary and secondary immunodeficiency diseases. Thymosin Fraction 5 consists of a family of polypeptides with molecular weights ranging from 1,000 to 15,000. Several of these polypeptides contribute individually to the biological activity of the parent compound. Two polypeptide components of thymosin Fraction 5, termed thymosin alpha1 and polypeptide beta1, have been characterized chemically and biologically. Thymosin alpha1 is a highly acidic molecule composed of 28 amino acid residues. This polypeptide has potent biological activity and has been found to be 10 to 1,000 times as active as thymosin Fraction 5 in one in vivo and several in vitro bioassay systems designed to measure differentiation and function of thymus-dependent lymphocytes (T cells). Polypeptide beta1, in contrast, is inactive in our bioassay systems, suggesting that it is not involved in thymic hormone action. Sequence analysis and homology studies have indicated that polypeptide beta1, although present in Fraction 5, does not contribute to the biological activity of thymosin Fraction 5.

Animals↗

PubMed1978

The biology of ethics or the ethics of biology? The biologist's quest for meaning.

The biologist's involvement in value issues concerning the metholology of biological sciences, in establishing the biological basis of ethics and in creating a value system based on biological knowledge is examined. It is proposed that the roots of this involvement are in the conflict of the knowledge-ethic with the established system of values and in the need for metaphysical explanation.

Biology↗

PubMed1977

Biological and immunological characterization of human luteinizing hormone: I. Biological profile in pituitary and plasma samples after electrofocusing.

Pituitary and plasma pools from postmenopausal women and plasma pools from women at midcycle were fractionated by electrofocusing in sucrose density gradients. The biological LH activity was determined in each of the electrofocusing fractions by the use of an in vitro bioassay method. A heterogeneous profile of LH activity was found in both pituitary and plasma samples with a large proportion present within the pH range 6.5-10. In a total of 11 electrofocusing runs 7 main regions of high LH activity were found within this range with mean pI values (+/- SD) of 6.75 +/- 0.08 (n = 6), 7.33 +/- 0.08 (11), 7.80 +/- 0.09 (11), 8.23 +/- 0.10 (11), 8.81 +/- 0.04 (7), 9.17 +/- 0.05 (6) and 9.55 (2). A significantly higher proportion of LH activity was found in the midcycle plasma samples (36%) in the pH regions with mean pI values of 8.81, 9.17 and 9.55 than in postmenopausal plasma (7%) and pituitary extracts (5%). This indicates that the profile of biologically active LH in women in the fertile age is different from that present in postmenopausal women. By detailed fractionation based on narrow pH range studies and the refocusing of specific peak fractions it was shown that each of the regions studied consisted of several peaks of LH activity indicating the presence of a large number of molecular species exhibiting varying degrees of LH activity. The relative proportions of these species showed considerable differences between sources but also between samples from the same source.

Animals↗

PubMed1979

Lipophilicity and biological acitivity. Drug transport and drug distribution in model systems and in biological systems.

Different equilibrium and non-equilibrium models are used to simulate drug transport and drug distribution. The percentage of absorbed drug, the rate constants of drug absorption and the drug concentrations in the different compartments of the models can be described quantitatively by the bilinear model, e.g., log ci = a log P-b log (betaP + 1) + c. A nearly perfect fit is obtained for the simulated data from this model. Drug absorption and distribution in biological systems can be explained and described by the model-derived equations. Examples from the literature include buccal absorption, gastric and intestinal in situ and in vitro absorption, colonic absorption, renal clearance, and absorption through the skin and the blood-brain barrier; in all those cases the bilinear model gives an excellent fit of the experimental data. Combination of the pH-partition theory with the bilinear model leads to a simple quantitative model for the precise description of the relationships between lipophilicity, degree of ionization, and absorption, distribution and biological activity of drugs.

Absorption↗

PubMed1976

Synthesis of biologically active spin-labelled radioactive cytidine diphosphodiglyceride, a novel probe for biological membranes.

A versatile synthesis of spin-labelled radioactive cytidine diphospho-sn-1,2-diacylglycerol (CDP-diglyceride) has been developed based on the combination of the enzymatic acylation of radioactive sn-glycero-3-phosphate with 12-doxyl stearic acid and the chemical conversion of the thus obtained spin-labelled radioactive phosphatidic acid with cytidine monophosphomorpholi-date into spin-labelled radioactive CDP-diglyceride. The method for the isolation and purification of the latter compound was described. This obtained CDP-[2-3H]diglyceride contained 10% of fatty acids of paramagnetic nature, presumably present as a covalently bound 12-doxyl stearic acid esters. The biological activity was tested by using the synthesized compound as a substrate in the mitochondrial biosynthesis of phosphatidylglycerol. It was found that spin-labelled CDP-[2-3H]diglyceride prepared as described can be converted in the presence of sn-[2-14C]-glycero-3-phosphate into a spin-labelled [2-3H, 2'-14C]phosphatidylglycerol with isolated rat liver mitochondria, establishing therefore that the site of its utilization is identical with the site of phosphatidylglycerol synthesis in isolated mitochondria, i.e. inner mitochondrial membrane. Results described demonstrate that the synthesized spin-labelled CDP-diglyceride can be used as a specific probe for the spin- and radioactive covalent labelling of polyglycerophosphatides of mitochondrial membranes. Some implications and further possibilities in the study of biological membranes using the spin-labelled radioactive CDP-diglyceride are discussed.

Animals↗

PubMed1976

Biological ion exchanger resins. X. The cytotonus hypothesis: biological contractility and the total regulation of cellular physiology through quantitative control of cell water.

Actin-like (A-L) fraction from normal E. coli was compared with the protein from a potassium-transport mutant strain, and the cell-swelling reaction of both strains was studied. Findings were: (a) The membrane fraction of the mutant by SDS electrophoresis is deficient in the A-L fragment relative to normal whereas the soluble supernatant contains an excess. (b) Important catalytic differences exist between the A-L fractions of the two strains. The parent strain accumulates potassium in low K+ and the A-L fraction polymerizes in low K+. But the A-L fraction from the mutant fails to polymerize in low K media in the K+ concentration region where the mutant fails at K+ uptake. (c) The parent cell swells during low K+ uptake whereas the mutant does not. It is constructed from this that the differences in the characterization of A-L fraction relative to normal are related to the loss of cell-swelling in the mutant and hence to the loss in alkali cation selectivity. Thus two physical mechanisms, one macroscopic and dependent on the Gregor relation for swelling equilibria in ion exchange resins, and one more microscopic based on the dielectric dependence of the coulomb force between ion pairs, could underly regulation of ion selectivity by cell swelling. A similar proposal is made for the regulation of electron transport and oxidative phosphorylation in mitochondria. These findings and interpretations justify a new hypothesis to the effect that cell hydration is regulated by contractile proteins. The hypothesis fits together important observations hitherto unexplained, to wit: (1) The "missing link" as to the role of intermediate metabolism in biological ion exchange. (2) The swelling of bacterial protoplasts and its relation to (Mg2 + Ca2+)ATPase activity. (3) The swelling-contraction cycles of mitochondria and their role in electron transport. (4) The role of ATPase's in transport. (5) The significance of actomyosin fibers in nerve endings. (6) The significance of altered actomyosin structures in the cancerous cell.

Actins↗

PubMed1978