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Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH) 1-3 . These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase 4-6 . A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3) 7 . Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-μas (0.31-pc) spatial offset between the red and blue photocentres of the Hα line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 × 10 8  solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 × 10 11  solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems., (© 2024. The Author(s).)

Recently, lattice titanium manufactured by additive manufacturing (AM) techniques has been utilized in various applications, including biomedical. The effects of topological design and processing parameters on the fatigue behaviour of such meta-biomaterials have been studied before. Most studies show that the fatigue life of additively manufactured lattice structures is limited. Post-processing techniques could play a major role in improving the fatigue of these promising biomaterials. This study aims to provide an in-depth investigation into the effects of heat treatments, hot isostatic pressing (HIP), sand blasting, and chemical etching on the microstructure, surface morphology, strength and fatigue resistance of selective laser melted titanium meta-biomaterials. It was found that the combination of microstructural design and surface engineering, induced by HIP and sand blasting respectively, allows to increase the endurance limit of these lattice meta-biomaterials by a factor of two. HIP treatment substantially decreased the internal porosity and transformed the microstructure to a more ductile mixture of α + β phases. Sand blasting allowed to eliminate surface imperfections and induced favourable compressive stress in the surface layer of the struts. STATEMENT OF SIGNIFICANCE: Additively manufactured metallic meta-biomaterials are progressively being used as bone replacement orthopedic implants. While there is a great amount of research related to topological designs and their effect on mechanical (e.g. stiffness), physical (e.g. mass transport), and biological (e.g. osseointegration) properties, fatigue lifetime of such structures remains limited. This study provides fundamental investigation into the combined effect of microstructural design and surface engineering of titanium meta-biomaterial, enabled through various post treatment methods ranging from heat treatments to physical and chemical surface modifications. The findings show that fatigue life is significantly improved by applying developed herein novel method, which effortlessly can be used on other bone-mimicking metallic meta-biomaterials., (Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

A 9-year-old Thoroughbred gelding presented with a 97-day history of poor performance and intermittent fever. Clinicopathologic changes included increased serum activity of γ-glutamyltransferase and alkaline phosphatase, mild hyperbilirubinemia, and leukocytosis with neutrophilia and lymphopenia. Abdominal ultrasound revealed hepatomegaly with hyperechoic hepatic parenchyma and biliary distention. Pathologic findings included marked hepatomegaly (liver 3.6% of body weight), firm hepatic consistency with a diffuse enhanced reticular pattern, severe portal bridging and sinusoidal fibrosis, oval cell/bile duct hyperplasia, and bile stasis. The differential diagnoses and diagnostic workup to achieve the diagnosis are briefly discussed., (© The Author(s) 2013.)

Background: Allergic reactions to natural rubber latex have increased during the past 10 years, especially in many health care workers (HCWs) who have high exposure to latex allergens. The prevalence of skin test reactions to natural rubber latex in Russia, the Commonwealth of Independent States (CIS), and eastern Europe is unknown., Objective: The purpose of this study was to determine the prevalence of skin test reactivity to natural rubber latex in a population of HCWs exposed to latex., Methods: Nine hundred one HCWs regularly exposed to latex were evaluated using an allergy history questionnaire. Subjects were tested for latex allergy by titrated skin prick test with a biologically standardized latex extract. The diagnosis of latex allergy was defined by the presence of clinical symptoms when exposed to latex along with a positive skin prick test to latex., Results: Forty-nine (5.4%) HCWs were skin test-positive to latex. Seventeen (1.9%) HCWs were classified as latex-allergic based upon positive skin tests to latex associated with allergy symptoms with exposure. Seven of 901 HCWs had experienced anaphylactic reactions to latex. The most frequently reported symptom related to latex exposure was contact urticaria., Conclusions: The prevalence of latex allergy among HCWs in Russia, the CIS, and adjacent eastern European countries is considerably less than reported in HCWs exposed to latex in western Europe and the United States. The low prevalence of latex allergy in Russia and the CIS suggests that lessened exposure to natural latex powdered gloves may diminish the prevalence of latex sensitization in HCWs in Russia and the CIS.

The growth of hemopoietic stem cells of C57BL/6 mice was explored in syngeneic and semi-syngeneic foci of heterotopic hemopoiesis, formed under the kidney capsule of (CBA x C57BL/6)F1 recipients with and without prior treatment with cyclophosphamide or fractionated irradiation, which is known to abrogate hybrid resistance and NK cell activity. Our results show that the suppression of the growth of parent stem cells in semi-syngeneic F1-recipients is due to NK cell participation. However, no inhibition was found in the growth of identical cells in the foci of syngeneic hemopoietic stroma in the same recipients, despite the presence of NK cell activity. The experimental model used shows clearly that hybrid resistance is the result of the joint involvement of NK cells and the semi-syngeneic stroma.

Bone marrow cells of various animal species and humans produce a group of bioregulatory peptides called myelopeptides (MPs). MPs have been isolated and purified, and their physico-chemical properties have been investigated. MPs have a wide spectrum of functional activities: immunoregulatory, differentiating, and opiate-like. A new immunocorrective drug, Myelopidum, which is used effectively in clinical practice for treating diseases accompanied by immunodeficiency, has been created on the basis of MPs. Administration of Myelopidum after surgery prevents 50% to 70% of postsurgical complications, particularly postsurgery pneumonia, and also normalizes the number and balance of T-helper cells, T-suppressor cells, and B-lymphocytes in patients with chronic pulmonary diseases, resulting in a beneficial clinical effect, including a significant prolongation of remission periods. Myelopidum is also used in veterinary medicine for prophylaxis and treatment of pneumonia and enteritis in newborn and young animals. The primary structure of several myelopeptides is established. The functional activities of two, MP-1 (Phe-Leu-Gly-Phe-Pro-Thr) and MP-2 (Leu-Val-Val-Tyr-Pro-Trp), are being investigated.

Myelopeptide 1 (MP-1) is hexapeptide originally isolated from porcine bone marrow cell culture. It was synthesized and its immunoregulatory properties were studied. MP-1 caused a 1.5-2-fold dose-dependent increase of antibody production in the culture of mouse immune lymph node cells. It abolished Con A induction of T suppressors in the suspension of mouse spleen cells and counteracted the inhibitory effect of T suppressors on antibody production. The inoculation of MP-1 (1 x 10(-9) g/mouse) to mice two weeks after their gamma-irradiation (2 Gy) resulted in an increase of antibody production up to 80.2 +/- 15.5% as compared to that in the irradiated control 37.6 +/- 12.0%. Immunofluorescent analysis revealed the specific binding of MP-1 with receptors on the target cells in the suspension of mouse spleen cells. It is supposed that MP-1 participates in the immunoregulatory processes in the living organism.

In order to investigate the possible role of pancreatic beta-cell p(64-69) antigens in the development of diabetes type 1, a monoclonal antibody (ICA-1) to the 64-69 kDa antigen family was produced and characterized. Short-term (0.25 mg per rat, intraperitoneally, daily for 9 days) and prolonged (0.125 mg per rat, intraperitoneally, three times a week for 8 weeks) administration of ICA-1 to Wistar rats caused the development of a diabetes-like reaction characterized by moderate hyperglycaemia, markedly reduced pancreatic insulin content, and depressed insulin secretion. After 9 days, histological changes in the pancreas indicative of early insulitis were also observed. Continued ICA-1 treatment increased mononuclear infiltration of the islets and progressive beta-cell damage became evident. In order to confirm the insulin-dependent character of this early-stage diabetes induced by ICA-1, rats were injected with insulin in liposomes, whereupon normalization of serum insulin levels was observed together with a decrease in mononuclear infiltration. These results indicate that the 64-69 kDa antigen family is closely related to the hypothetical primary target protein that may play a role in the development of autoimmune beta-cell destruction.

The aim of the present study was to characterize the expression of the pancreatic beta cell antigen family with molecular masses of 64 to 69 kDa [p(64-69)]. This antigen family was detected by immunoreactivity with biotinylated monoclonal antibody (Mab) ICA-1, and Mab against insulin. The molecular masses of the antigens affinity-purified from islet cell lysates by ICA-1 were 64, 67, and 69 kDa. Detailed analysis of p(64-69) expression was carried out on cultured islet cells reassociated into clusters of islet-like structures. Cell-fluorescence image processing by computerized image analysis, combined with transmission and scanning electron microscopy, of cells labelled with Mab ICA-1 and immunogold revealed the localization of the 64-65 kDa antigen family on the beta cell surface and its grouping on microvilli and near areas of fusion of the insulin-containing beta granules with the plasma membrane. In view of the effect of ICA-1 on insulin release and its localization on the beta cell surface in immunoreactions it is proposed that the p(64-69) antigen family is involved in insulin secretion.