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1.
Cell ; 186(21): 4652-4661.e13, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37734373

RESUMO

The mpox outbreak of 2022-2023 involved rapid global spread in men who have sex with men. We infected 18 rhesus macaques with mpox by the intravenous, intradermal, and intrarectal routes and observed robust antibody and T cell responses following all three routes of infection. Numerous skin lesions and high plasma viral loads were observed following intravenous and intradermal infection. Skin lesions peaked on day 10 and resolved by day 28 following infection. On day 28, we re-challenged all convalescent and 3 naive animals with mpox. All convalescent animals were protected against re-challenge. Transcriptomic studies showed upregulation of innate and inflammatory responses and downregulation of collagen formation and extracellular matrix organization following challenge, as well as rapid activation of T cell and plasma cell responses following re-challenge. These data suggest key mechanistic insights into mpox pathogenesis and immunity. This macaque model should prove useful for evaluating mpox vaccines and therapeutics.


Assuntos
Macaca mulatta , Monkeypox virus , Mpox , Animais , Humanos , Masculino , Homossexualidade Masculina , Mpox/imunologia , Minorias Sexuais e de Gênero , Monkeypox virus/fisiologia
2.
Genes Dev ; 36(5-6): 300-312, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35273075

RESUMO

Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that is a vital regulator of adipogenesis, insulin sensitivity, and lipid metabolism. Activation of PPARγ by antidiabetic thiazolidinediones (TZD) reverses insulin resistance but also leads to weight gain that limits the use of these drugs. There are two main PPARγ isoforms, but the specific functions of each are not established. Here we generated mouse lines in which endogenous PPARγ1 and PPARγ2 were epitope-tagged to interrogate isoform-specific genomic binding, and mice deficient in either PPARγ1 or PPARγ2 to assess isoform-specific gene regulation. Strikingly, although PPARγ1 and PPARγ2 contain identical DNA binding domains, we uncovered isoform-specific genomic binding sites in addition to shared sites. Moreover, PPARγ1 and PPARγ2 regulated a different set of genes in adipose tissue depots, suggesting distinct roles in adipocyte biology. Indeed, mice with selective deficiency of PPARγ1 maintained body temperature better than wild-type or PPARγ2-deficient mice. Most remarkably, although TZD treatment improved glucose tolerance in mice lacking either PPARγ1 or PPARγ2, the PPARγ1-deficient mice were protected from TZD-induced body weight gain compared with PPARγ2-deficient mice. Thus, PPARγ isoforms have specific and separable metabolic functions that may be targeted to improve therapy for insulin resistance and diabetes.


Assuntos
Resistência à Insulina , Tiazolidinedionas , Adipócitos/metabolismo , Animais , Regulação da Expressão Gênica , Resistência à Insulina/genética , Camundongos , PPAR gama/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(13): e2222073120, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36961924

RESUMO

Binding to the host cell receptors, CD4 and CCR5/CXCR4, triggers large-scale conformational changes in the HIV-1 envelope glycoprotein (Env) trimer [(gp120/gp41)3] that promote virus entry into the cell. CD4-mimetic compounds (CD4mcs) comprise small organic molecules that bind in the highly conserved CD4-binding site of gp120 and prematurely induce inactivating Env conformational changes, including shedding of gp120 from the Env trimer. By inducing more "open," antibody-susceptible Env conformations, CD4mcs also sensitize HIV-1 virions to neutralization by antibodies and infected cells to antibody-dependent cellular cytotoxicity (ADCC). Here, we report the design, synthesis, and evaluation of novel CD4mcs based on an indoline scaffold. Compared with our current lead indane scaffold CD4mc, BNM-III-170, several indoline CD4mcs exhibit increased potency and breadth against HIV-1 variants from different geographic clades. Viruses that were selected for resistance to the lead indane CD4mc, BNM-III-170, are susceptible to inhibition by the indoline CD4mcs. The indoline CD4mcs also potently sensitize HIV-1-infected cells to ADCC mediated by plasma from HIV-1-infected individuals. Crystal structures indicate that the indoline CD4mcs gain potency compared to the indane CD4mcs through more favorable π-π overlap from the indoline pose and by making favorable contacts with the vestibule of the CD4-binding pocket on gp120. The rational design of indoline CD4mcs thus holds promise for further improvements in antiviral activity, potentially contributing to efforts to treat and prevent HIV-1 infection.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Citotoxicidade Celular Dependente de Anticorpos , Proteína gp120 do Envelope de HIV , Antígenos CD4/metabolismo , Anticorpos Anti-HIV/farmacologia
4.
Proc Natl Acad Sci U S A ; 119(33): e2205276119, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35939699

RESUMO

Brown adipose tissue (BAT) is a key thermogenic organ whose expression of uncoupling protein 1 (UCP1) and ability to maintain body temperature in response to acute cold exposure require histone deacetylase 3 (HDAC3). HDAC3 exists in tight association with nuclear receptor corepressors (NCoRs) NCoR1 and NCoR2 (also known as silencing mediator of retinoid and thyroid receptors [SMRT]), but the functions of NCoR1/2 in BAT have not been established. Here we report that as expected, genetic loss of NCoR1/2 in BAT (NCoR1/2 BAT-dKO) leads to loss of HDAC3 activity. In addition, HDAC3 is no longer bound at its physiological genomic sites in the absence of NCoR1/2, leading to a shared deregulation of BAT lipid metabolism between NCoR1/2 BAT-dKO and HDAC3 BAT-KO mice. Despite these commonalities, loss of NCoR1/2 in BAT does not phenocopy the cold sensitivity observed in HDAC3 BAT-KO, nor does loss of either corepressor alone. Instead, BAT lacking NCoR1/2 is inflamed, particularly with respect to the interleukin-17 axis that increases thermogenic capacity by enhancing innervation. Integration of BAT RNA sequencing and chromatin immunoprecipitation sequencing data revealed that NCoR1/2 directly regulate Mmp9, which integrates extracellular matrix remodeling and inflammation. These findings reveal pleiotropic functions of the NCoR/HDAC3 corepressor complex in BAT, such that HDAC3-independent suppression of BAT inflammation counterbalances stimulation of HDAC3 activity in the control of thermogenesis.


Assuntos
Tecido Adiposo Marrom , Correpressor 1 de Receptor Nuclear , Correpressor 2 de Receptor Nuclear , Termogênese , Tecido Adiposo Marrom/metabolismo , Animais , Histona Desacetilases/metabolismo , Inflamação/metabolismo , Camundongos , Camundongos Knockout , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo , Correpressor 2 de Receptor Nuclear/genética , Correpressor 2 de Receptor Nuclear/metabolismo , Receptores do Ácido Retinoico/metabolismo , Termogênese/genética , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
5.
Gesundheitswesen ; 2024 Jun 21.
Artigo em Alemão | MEDLINE | ID: mdl-38631383

RESUMO

BACKGROUND AND AIM OF THE STUDY: One aim of the pact for the Public Health Service ("Pakt für den ÖGD") is to increase scientific activity in the Public Health Service (PHS). This study deals with the question, which methods related to health services research are known and applied in the PHS and which methods are needed by PHS employees in the federal state Baden-Württemberg in Germany. METHODS: Guideline-based interviews (focus group and individual interviews) were conducted with 12 persons at different hierarchy levels from public health departments in Baden-Württemberg. The interviews were subjected to content analysis acording to Kuckartz. RESULTS: The interviewees described their heterogeneous needs as well as their methodological competences. Staff members expressed existing competences more frequently than leaders. These competencies included those used in everyday work such as literature research in routinely collected data (e. g., school entry examination), or different methods for data analysis. Needs seemed to exist primarily in the area of data analysis and collection, but were also expressed in the area of basic scientific methods. Topics relating to guidelines for good scientific practice (e. g., ethics proposals) and publications were also rather less known. A need for a support from research institutions or higher authorities was frequently mentioned. In addition, motivation and barriers for research in public health departments were mentioned. CONCLUSION: This study shows that existing methodological competencies and needs are heterogeneous and can be attributed to the heterogeneous backgrounds and fields of activity of the interviewees. Competencies are indicated, for example, in literature research and analysis of existing data. There is a need in methods, for example, of data collection/analysis as well as in basic scientific methods and deepening of existing skills. Furthermore support offers regarding scientific methodological competence for public health departments are required. There is also a lack of research infrastructure (e. g. software, access to literature) and a legal basis. The results can serve as a basis for the design of demand-oriented methodological programs for employees of the PHS in Baden-Württemberg.

6.
Nature ; 546(7659): 544-548, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28614293

RESUMO

Brown adipose tissue is a thermogenic organ that dissipates chemical energy as heat to protect animals against hypothermia and to counteract metabolic disease. However, the transcriptional mechanisms that determine the thermogenic capacity of brown adipose tissue before environmental cold are unknown. Here we show that histone deacetylase 3 (HDAC3) is required to activate brown adipose tissue enhancers to ensure thermogenic aptitude. Mice with brown adipose tissue-specific genetic ablation of HDAC3 become severely hypothermic and succumb to acute cold exposure. Uncoupling protein 1 (UCP1) is nearly absent in brown adipose tissue lacking HDAC3, and there is also marked downregulation of mitochondrial oxidative phosphorylation genes resulting in diminished mitochondrial respiration. Remarkably, although HDAC3 acts canonically as a transcriptional corepressor, it functions as a coactivator of oestrogen-related receptor α (ERRα) in brown adipose tissue. HDAC3 coactivation of ERRα is mediated by deacetylation of PGC-1α and is required for the transcription of Ucp1, Ppargc1a (encoding PGC-1α), and oxidative phosphorylation genes. Importantly, HDAC3 promotes the basal transcription of these genes independently of adrenergic stimulation. Thus, HDAC3 uniquely primes Ucp1 and the thermogenic transcriptional program to maintain a critical capacity for thermogenesis in brown adipose tissue that can be rapidly engaged upon exposure to dangerously cold temperature.


Assuntos
Tecido Adiposo Marrom/metabolismo , Regulação da Expressão Gênica , Histona Desacetilases/metabolismo , Termogênese , Animais , Respiração Celular , Temperatura Baixa , Elementos Facilitadores Genéticos/genética , Temperatura Alta , Humanos , Masculino , Camundongos , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptores de Estrogênio/metabolismo , Termogênese/genética , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Receptor ERRalfa Relacionado ao Estrogênio
7.
Proc Natl Acad Sci U S A ; 116(37): 18691-18699, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451658

RESUMO

Ambient temperature influences the molecular clock and lipid metabolism, but the impact of chronic cold exposure on circadian lipid metabolism in thermogenic brown adipose tissue (BAT) has not been studied. Here we show that during chronic cold exposure (1 wk at 4 °C), genes controlling de novo lipogenesis (DNL) including Srebp1, the master transcriptional regulator of DNL, acquired high-amplitude circadian rhythms in thermogenic BAT. These conditions activated mechanistic target of rapamycin 1 (mTORC1), an inducer of Srebp1 expression, and engaged circadian transcriptional repressors REV-ERBα and ß as rhythmic regulators of Srebp1 in BAT. SREBP was required in BAT for the thermogenic response to norepinephrine, and depletion of SREBP prevented maintenance of body temperature both during circadian cycles as well as during fasting of chronically cold mice. By contrast, deletion of REV-ERBα and ß in BAT allowed mice to maintain their body temperature in chronic cold. Thus, the environmental challenge of prolonged noncircadian exposure to cold temperature induces circadian induction of SREBP1 that drives fuel synthesis in BAT and is necessary to maintain circadian body temperature during chronic cold exposure. The requirement for BAT fatty acid synthesis has broad implications for adaptation to cold.


Assuntos
Aclimatação , Tecido Adiposo Marrom/metabolismo , Ritmo Circadiano/fisiologia , Lipogênese/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Termogênese/genética , Animais , Temperatura Corporal , Temperatura Baixa/efeitos adversos , Regulação da Expressão Gênica/fisiologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Knockout , Modelos Animais , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
8.
BMC Cancer ; 18(1): 851, 2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-30144818

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NACT) is a standard approach of the multidisciplinary treatment of breast cancer. Depending on the biological subtype a pathological complete response in the breast (bpCR) can be achieved in up to 60% of the patients. However, only limited accuracy can be reached when using imaging for prediction of bpCR prior to surgery. Due to this diagnostic uncertainty, surgery after NACT is considered to be obligatory for all patients in order to either completely remove residual disease or to diagnose a bpCR histologically. The purpose of this trial is to evaluate the accuracy of a vacuum-assisted biopsy (VAB) to diagnose a bpCR after NACT prior to surgery. METHODS: This study is a multicenter, confirmative, one-armed, intra-individually-controlled, open, diagnostic trial. The study will take place at 21 trial sites in Germany. Six hundred female patients with breast cancer after completed NACT showing at least a partial response to NACT treatment will be enrolled. A vacuum-assisted biopsy (VAB) guided either by ultrasound or mammography will be performed followed by histopathological evaluation of the VAB specimen before standard, guideline-adherent breast surgery. The study is designed to prove that the false negative rate of the VAB is below 10%. DISCUSSION: As a bpCR is becoming a more frequent result after NACT, the question arises whether breast surgery is therapeutically necessary in such cases. To study this subject further, it will be crucial to develop a reliable test to diagnose a bpCR without surgery. During the study we anticipate possible problems in patient recruitment as the VAB intervention does not provide participating patients with any personal benefit. Hence, a proficient informed consent discussion with the patient and a detailed explanation of the study aim will be crucial for patient recruitment. Another critical issue is the histopathological VAB evaluation of a non-tumorous specimen as this may have been taken either from the former tumor region (bpCR) or outside of the (former) tumor region (non-representative VAB, sampling error). TRIAL REGISTRATION: The trial has been registered at clinicaltrials.gov with the identifier NCT02948764 on October 28, 2016 and at the German Clinical Trials Register ( DRKS00011761 ) on February 20, 2017. The date of enrolment of the first participant to the trial was on March 8, 2017.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Biópsia Guiada por Imagem/métodos , Terapia Neoadjuvante , Adolescente , Adulto , Idoso , Biópsia por Agulha/métodos , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Alemanha/epidemiologia , Humanos , Mamografia , Pessoa de Meia-Idade , Vácuo , Adulto Jovem
9.
PLoS Biol ; 13(10): e1002279, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26512759

RESUMO

Aging is the major risk factor for neurodegenerative diseases such as Alzheimer's disease, but little is known about the processes that lead to age-related decline of brain structures and function. Here we use RNA-seq in combination with high resolution histological analyses to show that aging leads to a significant deterioration of neurovascular structures including basement membrane reduction, pericyte loss, and astrocyte dysfunction. Neurovascular decline was sufficient to cause vascular leakage and correlated strongly with an increase in neuroinflammation including up-regulation of complement component C1QA in microglia/monocytes. Importantly, long-term aerobic exercise from midlife to old age prevented this age-related neurovascular decline, reduced C1QA+ microglia/monocytes, and increased synaptic plasticity and overall behavioral capabilities of aged mice. Concomitant with age-related neurovascular decline and complement activation, astrocytic Apoe dramatically decreased in aged mice, a decrease that was prevented by exercise. Given the role of APOE in maintaining the neurovascular unit and as an anti-inflammatory molecule, this suggests a possible link between astrocytic Apoe, age-related neurovascular dysfunction and microglia/monocyte activation. To test this, Apoe-deficient mice were exercised from midlife to old age and in contrast to wild-type (Apoe-sufficient) mice, exercise had little to no effect on age-related neurovascular decline or microglia/monocyte activation in the absence of APOE. Collectively, our data shows that neurovascular structures decline with age, a process that we propose to be intimately linked to complement activation in microglia/monocytes. Exercise prevents these changes, but not in the absence of APOE, opening up new avenues for understanding the complex interactions between neurovascular and neuroinflammatory responses in aging and neurodegenerative diseases such as Alzheimer's disease.


Assuntos
Envelhecimento , Apolipoproteínas E/metabolismo , Astrócitos/metabolismo , Complemento C1q/metabolismo , Atividade Motora , Doenças Neurodegenerativas/prevenção & controle , Doenças Vasculares/prevenção & controle , Animais , Apolipoproteínas E/sangue , Apolipoproteínas E/química , Apolipoproteínas E/genética , Astrócitos/imunologia , Astrócitos/patologia , Astrócitos/ultraestrutura , Barreira Hematoencefálica/imunologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/ultraestrutura , Ativação do Complemento , Complemento C1q/genética , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/ultraestrutura , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Homozigoto , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Monócitos/imunologia , Monócitos/metabolismo , Monócitos/patologia , Monócitos/ultraestrutura , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/imunologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Plasticidade Neuronal , Acoplamento Neurovascular , Estabilidade Proteica , Doenças Vasculares/imunologia , Doenças Vasculares/metabolismo , Doenças Vasculares/patologia
10.
J Neurosci ; 35(38): 13206-18, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26400949

RESUMO

Aging-related impairments in hippocampus-dependent cognition have been attributed to maladaptive changes in the functional properties of pyramidal neurons within the hippocampal subregions. Much evidence has come from work on CA1 pyramidal neurons, with CA3 pyramidal neurons receiving comparatively less attention despite its age-related hyperactivation being postulated to interfere with spatial processing in the hippocampal circuit. Here, we use whole-cell current-clamp to demonstrate that aged rat (29-32 months) CA3 pyramidal neurons fire significantly more action potentials (APs) during theta-burst frequency stimulation and that this is associated with faster AP repolarization (i.e., narrower AP half-widths and enlarged fast afterhyperpolarization). Using a combination of patch-clamp physiology, pharmacology, Western blot analyses, immunohistochemistry, and array tomography, we demonstrate that these faster AP kinetics are mediated by enhanced function and expression of Kv4.2/Kv4.3 A-type K(+) channels, particularly within the perisomatic compartment, of CA3 pyramidal neurons. Thus, our study indicates that inhibition of these A-type K(+) channels can restore the intrinsic excitability properties of aged CA3 pyramidal neurons to a young-like state. Significance statement: Age-related learning deficits have been attributed, in part, to altered hippocampal pyramidal neuronal function with normal aging. Much evidence has come from work on CA1 neurons, with CA3 neurons receiving comparatively less attention despite its age-related hyperactivation being postulated to interfere with spatial processing. Hence, we conducted a series of experiments to identify the cellular mechanisms that underlie the hyperexcitability reported in the CA3 region. Contrary to CA1 neurons, we demonstrate that postburst afterhyperpolarization is not altered with aging and that aged CA3 pyramidal neurons are able to fire significantly more action potentials and that this is associated with faster action potential repolarization through enhanced expression of Kv4.2/Kv4.3 A-type K(+) channels, particularly within the cell bodies of CA3 pyramidal neurons.


Assuntos
Envelhecimento/fisiologia , Região CA3 Hipocampal/citologia , Potenciais da Membrana/fisiologia , Células Piramidais/fisiologia , Canais de Potássio Shal/metabolismo , Análise de Variância , Animais , Biofísica , Relação Dose-Resposta a Droga , Estimulação Elétrica , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/farmacologia , Células Piramidais/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Potenciais Sinápticos/efeitos dos fármacos , Potenciais Sinápticos/fisiologia
12.
Cell Metab ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38889724

RESUMO

Deficiency of the epigenome modulator histone deacetylase 3 (HDAC3) in brown adipose tissue (BAT) impairs the ability of mice to survive in near-freezing temperatures. Here, we report that short-term exposure to mild cold temperature (STEMCT: 15°C for 24 h) averted lethal hypothermia of mice lacking HDAC3 in BAT (HDAC3 BAT KO) exposed to 4°C. STEMCT restored the induction of the thermogenic coactivator PGC-1α along with UCP1 at 22°C, which is greatly impaired in HDAC3-deficient BAT, and deletion of either UCP1 or PGC-1α prevented the protective effect of STEMCT. Remarkably, this protection lasted for up to 7 days. Transcriptional activator C/EBPß was induced by short-term cold exposure in mouse and human BAT and, uniquely, remained high for 7 days following STEMCT. Adeno-associated virus-mediated knockdown of BAT C/EBPß in HDAC3 BAT KO mice erased the persistent memory of STEMCT, revealing the existence of a C/EBPß-dependent and HDAC3-independent cold-adaptive epigenomic memory.

13.
Sci Transl Med ; 16(740): eadl4317, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536937

RESUMO

The 2022-2023 mpox outbreak triggered vaccination efforts using smallpox vaccines that were approved for mpox, including modified vaccinia Ankara (MVA; JYNNEOS), which is a safer alternative to live replicating vaccinia virus (ACAM2000). Here, we compare the immunogenicity and protective efficacy of JYNNEOS by the subcutaneous or intradermal routes, ACAM2000 by the percutaneous route, and subunit Ad35 vector-based L1R/B5R or L1R/B5R/A27L/A33R vaccines by the intramuscular route in rhesus macaques. All vaccines provided robust protection against high-dose intravenous mpox virus challenge with the current outbreak strain, with ACAM2000 providing near complete protection and JYNNEOS and Ad35 vaccines providing robust but incomplete protection. Protection correlated with neutralizing antibody responses as well as L1R/M1R- and B5R/B6R-specific binding antibody responses, although additional immune responses likely also contributed to protection. This study demonstrates the protective efficacy of multiple vaccine platforms against mpox virus challenge, including both current clinical vaccines and vectored subunit vaccines.


Assuntos
Mpox , Vacina Antivariólica , Animais , Vaccinia virus/genética , Macaca mulatta , Anticorpos Antivirais , Vacinas de Subunidades Antigênicas
15.
Anaesthesiologie ; 72(6): 433-444, 2023 06.
Artigo em Alemão | MEDLINE | ID: mdl-36930267

RESUMO

Currently, few robust data are available to provide estimates of the environmental footprint and in particular the CO2 emissions of medical devices; however, existing life cycle assessments largely indicate that reusable materials have more favorable emissions and environmental footprints compared to disposable items. Thus, the challenge for every anesthesiology department is to identify items that can be used as reusable products for ecological and other reasons.A prerequisite for the use of reusable items is hygienically correct reprocessing and packaging. Here, a distinction must be made between noncritical, semicritical and critical medical devices, depending on the type of use. In addition, a distinction must be made between categories A-C, depending on the complexity of the reprocessing.In this narrative review article common reusable items used in anesthesiology are categorized and a standardized decision algorithm for reprocessing routes is proposed. Special attention is also given to the packaging of medical devices, which can contribute to the ecological footprint to a relevant extent.This article further explains the framework under which reprocessing can take place and analyzes the current state of knowledge on the life cycle assessment of reprocessing reusable devices.This requires the special commitment of clinically active anesthesiologists to include ecological aspects in the decision to use disposable or reusable items. In the medium term, comprehensible ecological key numbers should be provided on every medical device to make the ecological costs of the articles understandable in addition to the monetary costs.


Assuntos
Anestesiologia , Anestésicos , Dióxido de Carbono , Equipamentos Descartáveis , Custos e Análise de Custo
16.
bioRxiv ; 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37425731

RESUMO

Broadly neutralizing antibodies (bnAbs) against HIV-1 target conserved epitopes, thereby inhibiting viral entry. Yet surprisingly, those recognizing linear epitopes in the HIV-1 gp41 membrane proximal external region (MPER) are elicited neither by peptide nor protein scaffold vaccines. Here, we observe that while Abs generated by MPER/liposome vaccines may exhibit human bnAb-like paratopes, B-cell programming without constraints imposed by the gp160 ectodomain selects Abs unable to access the MPER within its native "crawlspace". During natural infection, the flexible hinge of IgG3 partially mitigates steric occlusion of less pliable IgG1 subclass Abs with identical MPER specificity, until affinity maturation refines entry mechanisms. The IgG3 subclass maintains B-cell competitiveness, exploiting bivalent ligation resulting from greater intramolecular Fab arm length, offsetting weak antibody affinity. These findings suggest future immunization strategies.

17.
Nat Commun ; 14(1): 7218, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940661

RESUMO

Broadly neutralizing antibodies (bnAbs) against HIV-1 target conserved envelope (Env) epitopes to block viral replication. Here, using structural analyses, we provide evidence to explain why a vaccine targeting the membrane-proximal external region (MPER) of HIV-1 elicits antibodies with human bnAb-like paratopes paradoxically unable to bind HIV-1. Unlike in natural infection, vaccination with MPER/liposomes lacks a necessary structure-based constraint to select for antibodies with an adequate approach angle. Consequently, the resulting Abs cannot physically access the MPER crawlspace on the virion surface. By studying naturally arising Abs, we further reveal that flexibility of the human IgG3 hinge mitigates the epitope inaccessibility and additionally facilitates Env spike protein crosslinking. Our results suggest that generation of IgG3 subtype class-switched B cells is a strategy for anti-MPER bnAb induction. Moreover, the findings illustrate the need to incorporate topological features of the target epitope in immunogen design.


Assuntos
Infecções por HIV , HIV-1 , Vacinas , Humanos , Anticorpos Anti-HIV , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes , Sítios de Ligação de Anticorpos , Epitopos , Imunoglobulina G , Proteína gp41 do Envelope de HIV/química
18.
Thromb Haemost ; 121(10): 1310-1316, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33759144

RESUMO

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is an evolving treatment of severe aortic valve stenosis. However, thromboembolic events such as stroke are common, predominantly early after TAVI. Optimal periprocedural antithrombotic regime is unknown. Especially, as antithrombotic medication enhances bleeding risk, thrombin generation and platelet function are crucial in the pathogenesis of ischemic events. However, the impact of the TAVI procedure on thrombin formation and platelet reactivity is not known by now. METHODS: We evaluated thrombin levels using thrombin-antithrombin (TAT) complexes and prothrombin fragments (PTFs) using enzyme-linked immunosorbent assay. Furthermore, platelet reactivity was measured via light transmission aggregometry before and 2 hours after TAVI in 198 patients. RESULTS: TAT complexes and PTF F1 + 2 substantially increased during TAVI. Postprocedurally, TAT complexes and PTF were significantly higher after TAVI compared with percutaneous coronary intervention due to acute myocardial infarction, while preprocedural TAT complexes and PTF F1 + 2 did not differ. In contrast, platelet reactivity was not altered early after TAVI. Only adenosine diphosphate-induced aggregation was reduced, reflecting preprocedural loading with clopidogrel. CONCLUSION: In this pilot study, we were able to demonstrate that thrombin generation is significantly increased early after TAVI, while platelet function is not affected. Increased thrombin concentrations may contribute to the high risk of postprocedural thromboembolic events. This leads to the hypothesis that extended peri-interventional anticoagulation early after TAVI may be an approach to reduce thromboembolic events.


Assuntos
Estenose da Valva Aórtica/cirurgia , Plaquetas/metabolismo , Ativação Plaquetária , Trombina/metabolismo , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Antitrombina III , Estenose da Valva Aórtica/sangue , Estenose da Valva Aórtica/diagnóstico , Feminino , Humanos , Masculino , Fragmentos de Peptídeos/sangue , Peptídeo Hidrolases/sangue , Projetos Piloto , Agregação Plaquetária , Testes de Função Plaquetária , Protrombina , Índice de Gravidade de Doença , Fatores de Tempo , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
19.
Pharmacol Ther ; 213: 107592, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32492513

RESUMO

Lipid-lowering therapy is one major cornerstone of medical treatment of cardiovascular disease in order to modulate atherosclerosis. Statins, ezetimibe and novel PCSK9-inhibitors are already recommended in current guidelines and were shown to improve lipid profiles and have positive effects on the rate of ischemic events and cardiovascular mortality. Recent studies suggest that the concept of "The lower the better" might be valid at least regarding low density lipoproteins. In addition, lowering lipoprotein (a) still displays a major challenge in lipid therapy. Furthermore, also lowering triglycerides seems to improve cardiovascular outcome. Regarding triglycerides, icosapent ethyl, a polyunsaturated fatty acid recently attracted attention showing cardiovascular risk reduction due to triglyceride lowering. Therefore, new therapeutic strategies and drug classes are eagerly awaited. Targeting LDL, bempedoic acid and the siRNA inclisiran provide promising results. Moreover, regarding TG a monoclonal antibody called evinacumab and an antisense-oligonucleotide against ANGPTL3 showed effective TG-lowering. At least, using antisense-oligonucleotides against ApoC-III and Lp(a) resulted in promising outcomes. In this review, current and future options for lipid management are presented depending on different drug classes.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Hipolipemiantes/farmacologia , Lipídeos/sangue , Animais , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Humanos , Comportamento de Redução do Risco
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