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1.
EMBO Rep ; 24(3): e55536, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36705069

RESUMO

The cGAS-STING (cyclic GMP-AMP synthase-stimulator of interferon genes) axis is the predominant DNA sensing system in cells of the innate immune system. However, human T cells also express high levels of STING, while its role and physiological trigger remain largely unknown. Here, we show that the cGAS-STING pathway is indeed functional in human primary T cells. In the presence of a TCR-engaging signal, both cGAS and STING activation switches T cells into type I interferon-producing cells. However, T cell function is severely compromised following STING activation, as evidenced by increased cell death, decreased proliferation, and impaired metabolism. Interestingly, these different phenotypes bifurcate at the level of STING. While antiviral immunity and cell death require the transcription factor interferon regulatory factor 3 (IRF3), decreased proliferation is mediated by STING independently of IRF3. In summary, we demonstrate that human T cells possess a functional cGAS-STING signaling pathway that can contribute to antiviral immunity. However, regardless of its potential antiviral role, the activation of the cGAS-STING pathway negatively affects T cell function at multiple levels. Taken together, these results could help inform the future development of cGAS-STING-targeted immunotherapies.


Assuntos
Interferon Tipo I , Nucleotidiltransferases , Humanos , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Antivirais , Linfócitos T , Imunidade Inata
2.
J Allergy Clin Immunol ; 152(5): 1336-1344.e5, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37544411

RESUMO

BACKGROUND: Genetic defects in components of inflammasomes can cause autoinflammation. Biallelic loss-of-function mutations in dipeptidyl peptidase 9 (DPP9), a negative regulator of the NLRP1 and CARD8 inflammasomes, have recently been shown to cause an inborn error of immunity characterized by pancytopenia, skin manifestations, and increased susceptibility to infections. OBJECTIVE: We sought to study the molecular basis of autoinflammation in a patient with severe infancy-onset hyperinflammation associated with signs of fulminant hemophagocytic lymphohistiocytosis. METHODS: Using heterologous cell models as well as patient cells, we performed genetic, immunologic, and molecular investigations to identify the genetic cause and to assess the impact of the identified mutation on inflammasome activation. RESULTS: The patient exhibited pancytopenia with decreased neutrophils and T, B, and natural killer cells, and markedly elevated levels of lactate dehydrogenase, ferritin, soluble IL-2 receptor, and triglycerides. In addition, serum levels of IL-1ß and IL-18 were massively increased, consistent with inflammasome activation. Genetic analysis revealed a previously undescribed de novo mutation in DPP9 (c.755G>C, p.Arg252Pro) affecting a highly conserved amino acid residue. The mutation led to destabilization of the DPP9 protein as shown in transiently transfected HEK293T cells and in patient-derived induced pluripotent stem cells. Using functional inflammasome assays in HEK293T cells, we demonstrated that mutant DPP9 failed to restrain the NLRP1 and CARD8 inflammasomes, resulting in constitutive inflammasome activation. These findings suggest that the Arg252Pro DPP9 mutation acts in a dominant-negative manner. CONCLUSIONS: A de novo mutation in DPP9 leads to severe infancy-onset autoinflammation because of unleashed inflammasome activation.


Assuntos
Linfo-Histiocitose Hemofagocítica , Pancitopenia , Humanos , Proteínas Adaptadoras de Sinalização CARD/genética , Inflamassomos/genética , Inflamassomos/metabolismo , Linfo-Histiocitose Hemofagocítica/genética , Células HEK293 , Proteínas Reguladoras de Apoptose/genética , Mutação , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Proteínas de Neoplasias/genética
3.
J Exp Biol ; 225(14)2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35822351

RESUMO

The biomechanical demands of arboreal locomotion are generally thought to necessitate specialized kinetic and kinematic gait characteristics. While such data have been widely collected across arboreal quadrupeds, no study has yet explored how arboreal substrates influence the locomotor behavior of birds. Parrots - an ancient arboreal lineage that exhibit numerous anatomical specializations towards life in the trees - represent an ideal model group within which to examine this relationship. Here, we quantifiy limb loading patterns within the rosy-faced lovebird (Agapornis roseicollis) across a range of experimental conditions to define the circumstances under which arboreal gaits are triggered, and how, during arboreal walking, gait patterns change across substrates of varying diameter. In so doing, we address longstanding questions as to how the challenges associated with arboreality affect gait parameters. Arboreal locomotion was associated with the adoption of a sidling gait, which was employed exclusively on the small and medium diameter poles but not terrestrially. When sidling, the hindlimbs are decoupled into a distinct leading limb (which imparts exclusively braking forces) and trailing limb (which generates only propulsive forces). Sidling was also associated with relatively low pitching forces, even on the smallest substrate. Indeed, these forces were significantly lower than mediolateral forces experienced during striding on terrestrial and large diameter substrates. We propose that the adoption of sidling gaits is a consequence of avian foot morphology and represents a novel form of arboreal locomotion where inversion/eversion is impossible. Such movement mechanics is likely widespread among avian taxa and may also typify patterns of arboreal locomotion in humans.


Assuntos
Agapornis , Animais , Fenômenos Biomecânicos , Marcha , Humanos , Locomoção , Árvores
4.
BMC Nurs ; 21(1): 42, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35139834

RESUMO

BACKGROUND: Women with BRCA1/2 mutations are at high risk to develop breast and ovarian cancer. To support these women to participate in shared decision-making, structured nurse-led decision coaching combined with an evidence-based decision aid may be employed. In preparation of the interprofessional randomized controlled trial to evaluate a decision coaching program to support preventive decisions of healthy female BRCA 1/2 gene mutation carriers (EDCP-BRCA), we adapted and piloted an existing training program for specialized nurses and included elements from an existing physician communication training. METHODS: The training was adapted according to the six-step-approach for medical curriculum development. The educational design is based on experience- and problem-based learning. Subsequently, we conducted a qualitative pilot study. Nurses were recruited from six German centers for familial breast and ovarian cancer. The acceptability and feasibility were assessed by structured class observations, field notes and participants' feedback. Data were analyzed using qualitative content analysis. The training was revised according to the results. Due to the COVID-19 pandemic, the patient intervention was adapted as a virtual coaching and a brief additional training for nurses was added. RESULTS: The training consists of two modules (2 + 1 day) that teach competences in evidence-based medicine and patient information, (risk) communication and decision coaching. One pilot test was conducted with six nurses of which three were specialized and experienced in patient counselling. A final set of eight main categories was derived from the data: framework conditions; interaction; schedule, transparency of goals, content, methods, materials and practical relevance and feasibility. Overall, the training was feasible and comprehensible. Decision coaching materials were awkward to handle and decision coaching role plays were set too short. Therefore, materials will be sent out in advance and the training was extended. CONCLUSIONS: Specialized nurses are rarely available and nurse-led counselling is not routinely implemented in the centers of familial breast and ovarian cancer. However, training of less qualified nurses seems feasible. Decision coaching in a virtual format seems to be a promising approach. Further research is needed to evaluate its feasibility, acceptability and effectiveness. TRIAL REGISTRATION: The main trial is registered under DRKS-ID: DRKS00015527 .

5.
Malar J ; 16(1): 112, 2017 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-28284211

RESUMO

BACKGROUND: Despite increased efforts to control and ultimately eradicate human malaria, Plasmodium ovale malaria is for the most part outside the focus of research or public health programmes. Importantly, the understanding of P. ovale-nowadays regarded as the two distinct species P. ovale wallikeri and P. ovale curtisi-largely stems from case reports and case series lacking study designs providing high quality evidence. Consecutively, there is a lack of systematic evaluation of the clinical presentation, appropriate treatment and relapse characteristics of P. ovale malaria. The aim of this systematic review is to provide a systematic appraisal of the current evidence for severe manifestations, relapse characteristics and treatment options for human P. ovale malaria. METHODS AND RESULTS: This systematic review was performed according to the PRISMA guidelines and registered in the international prospective register for systematic reviews (PROSPERO 2016:CRD42016039214). P. ovale mono-infection was a strict inclusion criterion. Of 3454 articles identified by the literature search, 33 articles published between 1922 and 2015 met the inclusion criteria. These articles did not include randomized controlled trials. Five prospective uncontrolled clinical trials were performed on a total of 58 participants. P. ovale was sensitive to all tested drugs within the follow-up periods and on interpretable in vitro assays. Since its first description in 1922, only 18 relapsing cases of P. ovale with a total of 28 relapse events were identified in the scientific literature. There was however no molecular evidence for a causal relationship between dormant liver stages and subsequent relapses. A total of 22 severe cases of P. ovale malaria were published out of which five were fatal. Additionally, two cases of congenital P. ovale malaria were reported. CONCLUSIONS: Current knowledge of P. ovale malaria is based on small trials with minor impact, case reports and clinical observations. This systematic review highlights that P. ovale is capable of causing severe disease, severe congenital malaria and may even lead to death. Evidence for relapses in patients with P. ovale malaria adds up to only a handful of cases. Nearly 100 years after P. ovale's first description by Stephens the evidence for the clinical characteristics, relapse potential and optimal treatments for P. ovale malaria is still scarce.


Assuntos
Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Malária/patologia , Plasmodium ovale/isolamento & purificação , Antimaláricos/farmacologia , Humanos , Malária/parasitologia , Plasmodium ovale/efeitos dos fármacos , Recidiva
6.
Cureus ; 16(1): e52075, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38344517

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2), which became a pandemic in March 2020. Since that time, research has shed light on this disease's pulmonary, cardiac, and hematologic complications. However, we are still unraveling the complex neurologic sequelae of COVID-19. Here we present the case of a 58-year-old female who presented with weakness, gaze preference, and aphasia. She was diagnosed with a stroke which was managed medically. The patient returned two weeks later with memory loss and aphasia. An MRI was consistent with temporal lobe encephalitis, although a lumbar puncture was unremarkable. A polymerase chain reaction (PCR) test for COVID-19 was positive. Treatment was initiated for viral encephalitis with patient improvement. She was discharged a second time, and approximately three months later, she presented again with unrelenting headaches. Further imaging revealed a mass that was determined to be a grade IV glioma. Cases of glioma after viral encephalitis have been studied, but a clear link with COVID-19 has not been established.

7.
bioRxiv ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38645162

RESUMO

Human immunodeficiency virus type 1 (HIV-1) capsid, which is the target of the antiviral lenacapavir, protects the viral genome and binds multiple host proteins to influence intracellular trafficking, nuclear import, and integration. Previously, we showed that capsid binding to cleavage and polyadenylation specificity factor 6 (CPSF6) in the cytoplasm is competitively inhibited by cyclophilin A (CypA) binding and regulates capsid trafficking, nuclear import, and infection. Here we determined that a capsid mutant with increased CypA binding affinity had significantly reduced nuclear entry and mislocalized integration. However, disruption of CypA binding to the mutant capsid restored nuclear entry, integration, and infection in a CPSF6-dependent manner. Furthermore, relocalization of CypA expression from the cell cytoplasm to the nucleus failed to restore mutant HIV-1 infection. Our results clarify that sequential binding of CypA and CPSF6 to HIV-1 capsid is required for optimal nuclear entry and integration targeting, informing antiretroviral therapies that contain lenacapavir.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36767056

RESUMO

Women who are found to carry a BRCA1/2 pathogenic variant experience psychological distress due to an increased risk of breast and ovarian cancer. They may decide between different preventive options. In this secondary analysis of data collected alongside a larger randomized controlled trial, we are looking at 130 newly found BRCA1/2 pathogenic variant carriers and how their coping self-efficacy immediately after genetic test result disclosure is related to their psychological burden and status of preventive decision making. Participants received the Coping Self-Efficacy Scale, the Hospital Anxiety and Depression Scale, the Impact of Event Scale, the Decisional Conflict Scale, and the Stage of Decision-Making Scale after positive genetic test result disclosure. We found that women with higher coping self-efficacy showed fewer symptoms of anxiety or depression and were less affected by receiving the genetic test result in terms of post-traumatic stress. However, coping self-efficacy had no relationship with any decision-related criteria, such as decisional conflict or stage of decision making. This shows that despite its buffering capacity on psychological burden, possessing coping self-efficacy does not lead to more decisiveness in preference-sensitive decisions.


Assuntos
Adaptação Psicológica , Neoplasias da Mama , Testes Genéticos , Neoplasias Ovarianas , Autoeficácia , Feminino , Humanos , Proteína BRCA1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/psicologia , Genes BRCA1 , Genes BRCA2 , Morbidade , Mutação , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/psicologia
9.
Cell Metab ; 35(3): 487-503.e7, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36841242

RESUMO

Multiple cancers regulate oxidative stress by activating the transcription factor NRF2 through mutation of its negative regulator, KEAP1. NRF2 has been studied extensively in KEAP1-mutant cancers; however, the role of this pathway in cancers with wild-type KEAP1 remains poorly understood. To answer this question, we induced NRF2 via pharmacological inactivation of KEAP1 in a panel of 50+ non-small cell lung cancer cell lines. Unexpectedly, marked decreases in viability were observed in >13% of the cell lines-an effect that was rescued by NRF2 ablation. Genome-wide and targeted CRISPR screens revealed that NRF2 induces NADH-reductive stress, through the upregulation of the NAD+-consuming enzyme ALDH3A1. Leveraging these findings, we show that cells treated with KEAP1 inhibitors or those with endogenous KEAP1 mutations are selectively vulnerable to Complex I inhibition, which impairs NADH oxidation capacity and potentiates reductive stress. Thus, we identify reductive stress as a metabolic vulnerability in NRF2-activated lung cancers.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Fator 2 Relacionado a NF-E2 , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/metabolismo , NAD/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/genética , Transdução de Sinais
10.
J Exp Zool A Ecol Integr Physiol ; 337(3): 238-249, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34752693

RESUMO

While red-backed salamanders (Plethodon cinereus) are most often observed in terrestrial forested areas, several studies report arboreal substrate use and climbing behavior. However, salamanders do not have any of the anatomical features commonly observed in specialized climbing species (e.g., claws, setae, suction cups). Instead, salamanders cling to surfaces using the shear and adhesive properties of their mucous layer. In this study, we explore the capabilities and spatiotemporal gait patterns of arboreal locomotion in the red-backed salamander as they move across twelve substrate conditions ranging in diameter, orientation, and roughness. On arboreal substrates, red-backed salamanders decreased locomotor speed, stride frequency, phase and stride length, and increased duty factor and stride duration. Such responses have been observed in other non-salamander species and are posited to increase arboreal stability. Furthermore, these findings indicate that amphibian locomotion, or at least the locomotor behavior of the red-backed salamander, is not stereotyped and that some locomotor plasticity is possible in response to the demands of the external environment. However, red-backed salamanders were unable to locomote on any small-diameter or vertically-oriented coarse substrates. This finding provides strong evidence that the climbing abilities of red-backed salamanders are attributable solely to mucous adhesion and that this species is unable to produce the necessary external "gripping" forces to achieve fine-branch arboreal locomotion or scale substrates where adhesion is not possible. The red-backed salamander provides an ideal model for arboreal locomotor performance of anatomically-unspecialized amphibians and offers insight into transitionary stages in the evolution of arborealism in this lineage.


Assuntos
Árvores , Urodelos , Animais , Marcha , Locomoção , Urodelos/fisiologia
11.
J Exp Zool A Ecol Integr Physiol ; 337(4): 329-336, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34914867

RESUMO

During the last decade, biomechanical and kinematic studies have suggested that a belly-dragging gait may have represented a critical locomotor stage during tetrapod evolution. This form of locomotion is hypothesized to facilitate animals to move on land with relatively weaker pectoral muscles. The Indonesian blue-tongued skink (Tiliqua gigas) is known for its belly-dragging locomotion and is thought to employ many of the same spatiotemporal gait characteristics of stem tetrapods. Conversely, the savannah monitor (Varanus exanthematicus) employs a raised quadrupedal gait. Thus, differences in the energetic efficiency of locomotion between these taxa may elucidate the role of energetic optimization in driving gait shifts in early tetrapods. Five Tiliqua and four Varanus were custom-fitted for 3D printed helmets that, combined with a Field Metabolic System, were used to collect open-flow respirometry data including O2 consumption, CO2 production, water vapor pressure, barometric pressure, room temperature, and airflow rates. Energetic data were collected for each species at rest, and when walking at three different speeds. Energetic consumption in each taxon increased at greater speeds. On a per-stride basis, energetic costs appear similar between taxa. However, significant differences were observed interspecifically in terms of net cost of transport. Overall, energy expenditure was ~20% higher in Tiliqua at equivalent speeds, suggesting that belly-dragging does impart a tangible energetic cost during quadrupedal locomotion. This cost, coupled with the other practical constraints of belly-dragging (e.g., restricting top-end speed and reducing maneuverability in complex terrains) may have contributed to the adoption of upright quadrupedal walking throughout tetrapod locomotor evolution.


Assuntos
Marcha , Lagartos , Animais , Fenômenos Biomecânicos , Marcha/fisiologia , Indonésia , Locomoção/fisiologia , Caminhada/fisiologia
12.
Cureus ; 13(9): e18017, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34667692

RESUMO

Acquired thrombotic thrombocytopenic purpura (TTP) is an uncommon microangiopathic disorder that can have variable presentations and can be precipitated by a multitude of stressors to the body, most commonly sepsis. TTP is caused by a deficiency of ADAMTS13 leading to intravascular clotting causing thrombocytopenia and microangiopathic hemolytic anemia. TTP can be associated with various other pathologic conditions. One such rare association has been reported with diabetic ketoacidosis (DKA). Here, we present an even less appreciated presentation in association with DKA. A 62-year-old African American male with previously diagnosed prediabetes presented with DKA and developed hemodynamically significant bleeding. He was confirmed to have TTP that responded to plasmapheresis. TTP is a life-threatening illness if not treated urgently with plasmapheresis with or without rituximab. As acquired TTP most commonly occurs during stress on the body, it is important to treat the underlying stressor. Early identification and initiation of appropriate interventions are crucial to reducing mortality associated with TTP. Furthermore, we need to appreciate less commonly associated conditions such as DKA among patients.

13.
J Perinatol ; 41(1): 164-172, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32770031

RESUMO

OBJECTIVE: Inhaled NO (iNO) is used in the NICU for management of hypoxemic respiratory failure. The cost of iNO is significant and does not consistently improve outcomes in infants <34 weeks. PROJECT DESIGN: Our team used The Model for Improvement to design a quality improvement project to utilize iNO for appropriate indications, ensure response to therapy and initiate timely weaning. The project was carried out at a Level IV NICU and successful interventions spread to a smaller Level III NICU. RESULTS: This project demonstrated significant improvement in all measures; total iNO hours per month, average iNO hours per patient, and the percentage of prolonged iNO courses. With an estimated cost of $115/h, the cost per patient for iNO use declined by half from $21,620 to $10,580. CONCLUSIONS: Our team improved the value of iNO utilization at our institution and spread successful interventions to another NICU in our network.


Assuntos
Melhoria de Qualidade , Insuficiência Respiratória , Administração por Inalação , Humanos , Lactente , Recém-Nascido , Óxido Nítrico
14.
J Perinatol ; 40(6): 972-979, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32231258

RESUMO

Value in healthcare can be defined as providing the optimal outcome per health dollar spent. Improving the value of healthcare for patients and healthcare organizations requires an understanding and evaluation of the costs and benefits. Investing in quality improvement (QI) work can bring about financial results for healthcare organizations over time, have beneficial organizational effects, and improve outcomes for patients. This article continues a series of QI educational papers in the Journal of Perinatology, and reviews financial and economic measures used to create the business case for QI. Ultimately, the business case for QI is better defined as a business strategy for success.


Assuntos
Atenção à Saúde , Melhoria de Qualidade , Humanos
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