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1.
J Am Soc Nephrol ; 33(1): 49-57, 2022 01.
Article in English | MEDLINE | ID: mdl-34789546

ABSTRACT

BACKGROUND: Patients on hemodialysis have an elevated risk for COVID-19 but were not included in efficacy trials of SARS-CoV-2 vaccines. METHODS: We conducted a retrospective, observational study to estimate the real-world effectiveness and immunogenicity of two mRNA SARS-CoV-2 vaccines in a large, representative population of adult hemodialysis patients in the United States. In separate, parallel analyses, patients who began a vaccination series with BNT162b2 or mRNA-1273 in January and February 2021 were matched with unvaccinated patients and risk for outcomes were compared for days 1-21, 22-42, and ≥43 after first dose. In a subset of consented patients, blood samples were collected approximately 28 days after the second dose and anti-SARS-CoV-2 immunoglobulin G was measured. RESULTS: A total of 12,169 patients received the BNT162b2 vaccine (matched with 44,377 unvaccinated controls); 23,037 patients received the mRNA-1273 vaccine (matched with 63,243 unvaccinated controls). Compared with controls, vaccinated patients' risk of being diagnosed with COVID-19 postvaccination became progressively lower during the study period (hazard ratio and 95% confidence interval for BNT162b2 was 0.21 [0.13, 0.35] and for mRNA-1273 was 0.27 [0.17, 0.42] for days ≥43). After a COVID-19 diagnosis, vaccinated patients were significantly less likely than unvaccinated patients to be hospitalized (for BNT162b2, 28.0% versus 43.4%; for mRNA-1273, 37.2% versus 45.6%) and significantly less likely to die (for BNT162b2, 4.0% versus 12.1%; for mRNA-1273, 5.6% versus 14.5%). Antibodies were detected in 98.1% (309/315) and 96.0% (308/321) of BNT162b2 and mRNA-1273 patients, respectively. CONCLUSIONS: In patients on hemodialysis, vaccination with BNT162b2 or mRNA-1273 was associated with a lower risk of COVID-19 diagnosis and lower risk of hospitalization or death among those diagnosed with COVID-19. SARS-CoV-2 antibodies were detected in nearly all patients after vaccination. These findings support the use of these vaccines in this population.


Subject(s)
2019-nCoV Vaccine mRNA-1273/administration & dosage , 2019-nCoV Vaccine mRNA-1273/immunology , BNT162 Vaccine/administration & dosage , BNT162 Vaccine/immunology , COVID-19/immunology , COVID-19/prevention & control , Renal Dialysis/adverse effects , SARS-CoV-2/immunology , Aged , Aged, 80 and over , Antibodies, Viral/blood , Dose-Response Relationship, Immunologic , Female , Humans , Male , Middle Aged , Prospective Studies , Retrospective Studies , Risk Factors , Treatment Outcome
2.
Philos Trans R Soc Lond B Biol Sci ; 376(1816): 20190714, 2021 01 18.
Article in English | MEDLINE | ID: mdl-33250025

ABSTRACT

In many theories on the social and cultural evolution of human societies, the number and density of people living together in a given time and region is a crucial factor. Because direct data on past demographic developments are lacking, and reliability and validity of demographic proxies require careful evaluation, the topic has been approached from several different directions. This paper provides an introduction to a geostatistical approach for estimating prehistoric population size and density, the so-called Cologne Protocol and discusses underlying theoretical assumptions and upscaling transfer-functions between different spatial scale levels. We describe and compare the specifics for farming and for foraging societies and, using examples, discuss a diachronic series of estimates, covering the population dynamics of roughly 40 kyr of European prehistory. Ethnohistoric accounts, results from other approaches-including absolute (ethno-environmental models) and relative estimates (site-numbers, dates as data, etc.) allow a first positioning of the estimates within this field of research. Future enhancements, applications and testing of the Cologne Protocol are outlined and positioned within the general theoretical and methodological avenues of palaeodemographic research. In addition, we provide manuals for modelling Core Areas in MapInfo, ArcGIS, QGIS/Saga and R. This article is part of the theme issue 'Cross-disciplinary approaches to prehistoric demography'.


Subject(s)
Archaeology , Demography , Life Style , Europe , Humans , Population Dynamics
3.
Infect Immun ; 83(2): 514-21, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25404025

ABSTRACT

Severe infection, including sepsis, is an increasing clinical problem that causes prolonged morbidity and substantial mortality. At present, antibiotics are essentially the only pharmacological treatment for sepsis. The incidence of resistance to antibiotics is increasing; therefore, it is critical to find new therapies for sepsis. Staphylococcus aureus is a major cause of septic mortality. Neutrophils play an important role in the defense against bacterial infections. We have shown that a diet with high levels of dietary saturated fatty acids decreases survival in septic mice, but the mechanisms behind this remain elusive. The aim of the present study was to investigate how the differences in dietary fat composition affect survival and bacterial load after experimental septic infection and neutrophil function in uninfected mice. We found that, after S. aureus infection, mice fed a polyunsaturated high-fat diet (HFD-P) for 8 weeks had increased survival and decreased bacterial load during sepsis compared with mice fed a saturated high-fat diet (HFD-S), similar to mice fed a low-fat diet (LFD). Uninfected mice fed HFD-P had a higher frequency of neutrophils in bone marrow than mice fed HFD-S. In addition, mice fed HFD-P had a higher frequency of neutrophils recruited to the site of inflammation in response to peritoneal injection of thioglycolate than mice fed HFD-S. Differences between the proportion of dietary protein and carbohydrate did not affect septic survival at all. In conclusion, polyunsaturated dietary fat increased both survival and efficiency of bacterial clearance during septic S. aureus infection. Moreover, this diet increased the frequency and chemotaxis of neutrophils, key components of the immune response to S. aureus infections.


Subject(s)
Bacterial Load/drug effects , Dietary Fats, Unsaturated/immunology , Fatty Acids, Unsaturated/administration & dosage , Neutrophils/immunology , Staphylococcal Infections/immunology , Animals , Bone Marrow Cells/immunology , Cathepsin D/biosynthesis , Chemotaxis/immunology , Diet , Diet, High-Fat/adverse effects , Inflammation/chemically induced , Inflammation/immunology , Male , Mice , Mice, Inbred C57BL , Sepsis/immunology , Sepsis/microbiology , Staphylococcus aureus/immunology , Thioglycolates
4.
Hum Biol ; 81(2-3): 357-80, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19943751

ABSTRACT

Abstract We describe a combination of methods applied to obtain reliable estimations of population density using archaeological data. The combination is based on a hierarchical model of scale levels. The necessary data and methods used to obtain the results are chosen so as to define transfer functions from one scale level to another. We apply our method to data sets from western Germany that cover early Neolithic, Iron Age, Roman, and Merovingian times as well as historical data from AD 1800. Error margins and natural and historical variability are discussed. Our results for nonstate societies are always lower than conventional estimations compiled from the literature, and we discuss the reasons for this finding. At the end, we compare the calculated local and global population densities with other estimations from different parts of the world.


Subject(s)
Cultural Evolution/history , Population Density , Archaeology/statistics & numerical data , Culture , Demography , Europe , History, 15th Century , History, 16th Century , History, 17th Century , History, 18th Century , History, 19th Century , History, Ancient , History, Medieval , Humans , Models, Genetic , Models, Statistical , Population Dynamics
5.
Amyloid ; 12(4): 246-50, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16399650

ABSTRACT

OBJECTIVE: The goal of this study was to examine in vitro tissue stiffness and contractile performance in myocardial amyloidosis. BACKGROUND: Primary systemic amyloidosis involves the deposition of amyloid protein in mesodermal tissues including the heart. Functional assessment of cardiac amyloidosis is usually performed using echocardiography. However, this technique does not involve assessment of preload-dependent contractile reserve (the Frank-Starling mechanism). METHODS: At the time of heart transplantation, isolated myocardial trabeculae were dissected from the right ventricle of a patient with primary systemic amyloidosis. In vitro length-tension experiments were performed and trabeculae were subsequently fixed, sectioned and stained with crystal violet to determine amyloid deposition. RESULTS: Among the nine trabeculae capable of generating force transients, various combinations of myocardial stiffness and contractile performance were observed including normal stiffness and contractility, severely increased stiffness with impaired contractility and hybrid patterns. Histological analysis demonstrated varying degrees of amyloid deposition among sampled trabeculae. CONCLUSIONS: Our findings extend previous reports of functional heterogeneity among patients by demonstrating functional heterogeneity within a single patient's heart. Our findings also highlight the functional interdependence of passive stiffness and systolic performance in the diseased myocardium and demonstrate the value of dynamic assessments of myocardial performance.


Subject(s)
Amyloidosis/physiopathology , Heart/physiopathology , Isometric Contraction , Myocardial Contraction , Myocardial Ischemia/physiopathology , Amyloidosis/pathology , Amyloidosis/surgery , Female , Heart Transplantation , Humans , Kidney Transplantation , Middle Aged , Myocardial Ischemia/pathology , Myocardial Ischemia/surgery , Myocardium/pathology , Tensile Strength
6.
Circ Res ; 92(10): 1107-14, 2003 May 30.
Article in English | MEDLINE | ID: mdl-12714565

ABSTRACT

Development of vascular restenosis is a multifaceted process characterized by migration and proliferation of vascular smooth muscle cells (VSMCs), resulting in loss of lumen diameter. Characterization of proteins that mediate this process is essential in our understanding of the pathogenesis of arterial injury. Allograft inflammatory factor-1 (AIF-1) is a cytoplasmic, calcium-binding protein that is expressed in VSMCs by allograft and balloon angioplasty injury. AIF-1 is not present in cultured human VSMCs but is induced by cytokines, and overexpression of AIF-1 results in increased VSMC growth and cell-cycle gene expression. To characterize AIF-1 modulatory effects in primary human VSMCs, AIF-1-interacting proteins were identified by an AIF-1/glutathione S transferase fusion protein affinity assay. MALDI-TOF mass spectrophotometric amino analysis identified actin as an AIF-1 interacting protein. This interaction was verified by coimmunoprecipitation. This is a functional interaction, because AIF-1 binds to and polymerizes F-actin in vitro. In unstimulated VSMCs, AIF-1 colocalizes with F-actin but translocates to lamellipodia on stimulation with platelet-derived growth factor. VSMCs stably transduced with AIF-1 retrovirus migrate 2.6-fold more rapidly (85.1+/-2.9 versus 225.5+/-16.6; P<0.001) in response to platelet-derived growth factor versus control cells. AIF-1 colocalizes with Rac1, and AIF-1-transduced VSMCs show a constitutive and enhanced activation of Rac1, providing a mechanism for the increased migration. These data indicate that AIF-1 binds and polymerizes F actin and also regulates Rac1 activity and VSMC migration. Considering the AIF-1 expression pattern in injured arteries, this suggests that AIF-1 may be involved in the cytoskeletal signaling network leading to vascular remodeling.


Subject(s)
Actins/metabolism , Calcium-Binding Proteins/metabolism , Cell Movement/physiology , Muscle, Smooth, Vascular/metabolism , rac1 GTP-Binding Protein/metabolism , Cell Movement/drug effects , Cells, Cultured , Coronary Vessels/cytology , Cytoskeleton/metabolism , DNA-Binding Proteins , Electrophoresis, Polyacrylamide Gel , Enzyme Activation/drug effects , Enzyme Activation/physiology , Humans , Microfilament Proteins , Muscle, Smooth, Vascular/cytology , Protein Binding/drug effects , Protein Binding/physiology , Signal Transduction/physiology
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