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2.
J Proteome Res ; 23(7): 2474-2494, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38850255

RESUMO

Protein glycosylation is a ubiquitous process observed across all domains of life. Within the human pathogen Acinetobacter baumannii, O-linked glycosylation is required for virulence; however, the targets and conservation of glycosylation events remain poorly defined. In this work, we expand our understanding of the breadth and site specificity of glycosylation within A. baumannii by demonstrating the value of strain specific glycan electron-transfer/higher-energy collision dissociation (EThcD) triggering for bacterial glycoproteomics. By coupling tailored EThcD-triggering regimes to complementary glycopeptide enrichment approaches, we assessed the observable glycoproteome of three A. baumannii strains (ATCC19606, BAL062, and D1279779). Combining glycopeptide enrichment techniques including ion mobility (FAIMS), metal oxide affinity chromatography (titanium dioxide), and hydrophilic interaction liquid chromatography (ZIC-HILIC), as well as the use of multiple proteases (trypsin, GluC, pepsin, and thermolysis), we expand the known A. baumannii glycoproteome to 33 unique glycoproteins containing 42 glycosylation sites. We demonstrate that serine is the sole residue subjected to glycosylation with the substitution of serine for threonine abolishing glycosylation in model glycoproteins. An A. baumannii pan-genome built from 576 reference genomes identified that serine glycosylation sites are highly conserved. Combined this work expands our knowledge of the conservation and site specificity of A. baumannii O-linked glycosylation.


Assuntos
Acinetobacter baumannii , Glicoproteínas , Polissacarídeos , Proteômica , Serina , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Acinetobacter baumannii/química , Glicosilação , Serina/metabolismo , Serina/química , Proteômica/métodos , Glicoproteínas/metabolismo , Glicoproteínas/química , Glicoproteínas/genética , Polissacarídeos/metabolismo , Polissacarídeos/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Glicopeptídeos/análise , Glicopeptídeos/química , Glicopeptídeos/metabolismo , Cromatografia Líquida
3.
Biochem Soc Trans ; 52(3): 1373-1384, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38716972

RESUMO

Bacteriophages (phages) are viruses specific to bacteria that target them with great efficiency and specificity. Phages were first studied for their antibacterial potential in the early twentieth century; however, their use was largely eclipsed by the popularity of antibiotics. Given the surge of antimicrobial-resistant strains worldwide, there has been a renaissance in harnessing phages as therapeutics once more. One of the key advantages of phages is their amenability to modification, allowing the generation of numerous derivatives optimised for specific functions depending on the modification. These enhanced derivatives could display higher infectivity, expanded host range or greater affinity to human tissues, where some bacterial species exert their pathogenesis. Despite this, there has been a noticeable discrepancy between the generation of derivatives in vitro and their clinical application in vivo. In most instances, phage therapy is only used on a compassionate-use basis, where all other treatment options have been exhausted. A lack of clinical trials and numerous regulatory hurdles hamper the progress of phage therapy and in turn, the engineered variants, in becoming widely used in the clinic. In this review, we outline the various types of modifications enacted upon phages and how these modifications contribute to their enhanced bactericidal function compared with wild-type phages. We also discuss the nascent progress of genetically modified phages in clinical trials along with the current issues these are confronted with, to validate it as a therapy in the clinic.


Assuntos
Bacteriófagos , Engenharia Genética , Terapia por Fagos , Terapia por Fagos/métodos , Humanos , Bacteriófagos/genética , Infecções Bacterianas/terapia , Bactérias/virologia , Bactérias/genética , Animais , Antibacterianos/uso terapêutico
4.
Microbiol Spectr ; 12(6): e0034624, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38709084

RESUMO

Across the Burkholderia genus O-linked protein glycosylation is highly conserved. While the inhibition of glycosylation has been shown to be detrimental for virulence in Burkholderia cepacia complex species, such as Burkholderia cenocepacia, little is known about how specific glycosylation sites impact protein functionality. Within this study, we sought to improve our understanding of the breadth, dynamics, and requirement for glycosylation across the B. cenocepacia O-glycoproteome. Assessing the B. cenocepacia glycoproteome across different culture media using complementary glycoproteomic approaches, we increase the known glycoproteome to 141 glycoproteins. Leveraging this repertoire of glycoproteins, we quantitively assessed the glycoproteome of B. cenocepacia using Data-Independent Acquisition (DIA) revealing the B. cenocepacia glycoproteome is largely stable across conditions with most glycoproteins constitutively expressed. Examination of how the absence of glycosylation impacts the glycoproteome reveals that the protein abundance of only five glycoproteins (BCAL1086, BCAL2974, BCAL0525, BCAM0505, and BCAL0127) are altered by the loss of glycosylation. Assessing ΔfliF (ΔBCAL0525), ΔmotB (ΔBCAL0127), and ΔBCAM0505 strains, we demonstrate the loss of FliF, and to a lesser extent MotB, mirror the proteomic effects observed in the absence of glycosylation in ΔpglL. While both MotB and FliF are essential for motility, we find loss of glycosylation sites in MotB or FliF does not impact motility supporting these sites are dispensable for function. Combined this work broadens our understanding of the B. cenocepacia glycoproteome supporting that the loss of glycoproteins in the absence of glycosylation is not an indicator of the requirement for glycosylation for protein function. IMPORTANCE: Burkholderia cenocepacia is an opportunistic pathogen of concern within the Cystic Fibrosis community. Despite a greater appreciation of the unique physiology of B. cenocepacia gained over the last 20 years a complete understanding of the proteome and especially the O-glycoproteome, is lacking. In this study, we utilize systems biology approaches to expand the known B. cenocepacia glycoproteome as well as track the dynamics of glycoproteins across growth phases, culturing media and in response to the loss of glycosylation. We show that the glycoproteome of B. cenocepacia is largely stable across conditions and that the loss of glycosylation only impacts five glycoproteins including the motility associated proteins FliF and MotB. Examination of MotB and FliF shows, while these proteins are essential for motility, glycosylation is dispensable. Combined this work supports that B. cenocepacia glycosylation can be dispensable for protein function and may influence protein properties beyond stability.


Assuntos
Proteínas de Bactérias , Burkholderia cenocepacia , Glicoproteínas , Proteômica , Glicosilação , Burkholderia cenocepacia/metabolismo , Burkholderia cenocepacia/genética , Burkholderia cenocepacia/crescimento & desenvolvimento , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Glicoproteínas/metabolismo , Glicoproteínas/genética , Proteoma/metabolismo
5.
Nutr Health ; : 2601060241246353, 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38584400

RESUMO

Background: Mindful eating is a promising strategy to address problematic eating behaviors; however, little is known about its applicability during pregnancy. No studies have examined the combined effects of mindful and practical eating skills on eating behaviors. Aim: We examined associations between mindful and practical eating skills and eating behaviors (nutritional intake and emotional eating) among pregnant women who received psychoeducation on healthy eating and pregnancies. Methods: Participants were racially-diverse pregnant women (14-42 years) from four clinical sites in Detroit, Michigan, and Nashville, Tennessee (N = 741). We conducted multiple linear regression to examine associations between mindful (hunger cues, satiety cues, mindful check-ins) and practical (food diary/journal, MyPlate method) eating skills and nutritional intake. We calculated residualized change scores to represent changes in the quality of nutritional intake from second to third trimester. We performed multiple logistic regression to examine associations between mindful and practical eating skills and emotional eating. Results: Women improved over time in eating behaviors (better nutrition, less emotional eating). Regular use of MyPlate was associated with better nutritional intake (unstandardized coefficient [B] = -0.61), but food diaries were not. We found a significant interaction in predicting emotional eating: For those regularly paying attention to hunger cues, some use of MyPlate (Adjusted Odds Ratio [AOR] = 0.39) and especially regular use of MyPlate (AOR = 0.13) reduced the likelihood of emotional eating during pregnancy. Conclusion: Enhancing both mindful and practical eating skills, such as paying attention to hunger cues, and using the MyPlate method, may facilitate pregnant women's ability to improve their eating behaviors.

6.
J Affect Disord ; 354: 656-661, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38484882

RESUMO

BACKGROUND: Discrimination is an important social determinant of perinatal depression; however, evidence is limited regarding modifiable social and psychological factors that may moderate this association. We examined whether social support and resilience could protect against the adverse effects of discrimination on perinatal depressive symptoms. METHODS: Pregnant people (N = 589) receiving Expect With Me group prenatal care in Nashville, TN and Detroit, MI completed surveys during third trimester of pregnancy and six months postpartum. Linear regression models tested the association between discrimination and depressive symptoms, and the moderating effects of social support and resilience, during pregnancy and postpartum. RESULTS: The sample was predominantly Black (60.6 %), Hispanic (15.8 %) and publicly insured (71 %). In multivariable analyses, discrimination was positively associated with depressive symptoms during pregnancy (B = 4.44, SE = 0.37, p ≤0.001) and postpartum (B = 3.78, SE = 0.36, p < 0.001). Higher social support and resilience were associated with less depressive symptoms during pregnancy (B = -0.49, SE = 0.08, p < 0.001 and B = -0.67, SE = 0.10, p < 0.001, respectively) and postpartum (B = -0.32, SE = 0.07, p < 0.001 and B = -0.56, SE = 0.08, p < 0.001, respectively). Social support was protective against discrimination (pregnancy interaction B = -0.23, SE = 0.09, p = 0.011; postpartum interaction B = -0.35, SE = 0.07, p < 0.001). There was no interaction between discrimination and resilience at either time. LIMITATIONS: The study relied on self-reported measures and only included pregnant people who received group prenatal care in two urban regions, limiting generalizability. CONCLUSIONS: Social support and resilience may protect against perinatal depressive symptoms. Social support may also buffer the adverse effects of discrimination on perinatal depressive symptoms, particularly during the postpartum period.


Assuntos
Depressão Pós-Parto , Resiliência Psicológica , Gravidez , Feminino , Humanos , Depressão/psicologia , Período Pós-Parto/psicologia , Apoio Social , Cuidado Pré-Natal , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/prevenção & controle
7.
Implement Sci Commun ; 5(1): 20, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439113

RESUMO

BACKGROUND: Group prenatal care enhances quality of care, improves outcomes, and lowers costs. However, this healthcare innovation is not widely available. Using a case-study approach, our objectives were to (1) examine organizational characteristics that support implementation of Expect With Me group prenatal care and (2) identify key factors influencing adoption and sustainability. METHODS: We studied five clinical sites implementing group prenatal care, collecting qualitative data including focus group discussions with clinicians (n = 4 focus groups, 41 clinicians), key informant interviews (n = 9), and administrative data. We utilized a comparative qualitative case-study approach to characterize clinical sites and explain organizational traits that fostered implementation success. We characterized adopting and non-adopting (unable to sustain group prenatal care) sites in terms of fit for five criteria specified in the Framework for Transformational Change: (1) impetus to transform, (2) leadership commitment to quality, (3) improvement initiatives that engage staff, (4) alignment to achieve organization-wide goals, and (5) integration. RESULTS: Two sites were classified as adopters and three as non-adopters based on duration, frequency, and consistency of group prenatal care implementation. Adopters had better fit with the five criteria for transformational change. Adopting organizations were more successful implementing group prenatal care due to alignment between organizational goals and resources, dedicated healthcare providers coordinating group care, space for group prenatal care sessions, and strong commitment from organization leadership. CONCLUSIONS: Adopting sites were more likely to integrate group prenatal care when stakeholders achieved alignment across staff on organizational change goals, leadership buy-in, and committed institutional support and dedicated resources to sustain it. TRIAL REGISTRATION: The Expect With Me intervention's design and hypotheses were preregistered: https://clinicaltrials.gov/study/NCT02169024 . Date: June 19, 2014.

8.
Sci Rep ; 14(1): 3207, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332238

RESUMO

Many previous studies have investigated visual distance perception, especially for small to moderate distances. Few experiments, however, have evaluated the perception of large distances (e.g., 100 m or more). The studies that have been conducted have found conflicting results (diametrically opposite conclusions). In the current experiment, the functions relating actual and perceived distance were obtained for sixteen adult observers using the method of equal appearing intervals. These functions relating perceived and actual distance were obtained for outdoor viewing in a typical University environment-the experiment was conducted along a sidewalk adjacent to a typical street where campus buildings, trees, street signs, etc., were visible. The overall results indicated perceptual compression of distances in depth so that the stimulus distance intervals appeared significantly shorter than the actual (physical) distance intervals. It is important to note, however, that there were sizeable individual differences-the judgments of half of the observers were relatively accurate, whereas the judgments of the remaining half were inaccurate to varying degrees. The results of the experiment demonstrate that there is no single function that describes how human observers visually perceive large distance intervals in outdoor environments.


Assuntos
Compressão de Dados , Percepção Visual , Adulto , Humanos , Percepção de Distância , Julgamento , Individualidade , Percepção de Profundidade
9.
Lancet Respir Med ; 12(4): 281-293, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38310914

RESUMO

BACKGROUND: Exposure to household air pollution from polluting domestic fuel (solid fuel and kerosene) represents a substantial global public health burden and there is an urgent need for rapid transition to clean domestic fuels. Gas for cooking and heating might possibly affect child asthma, wheezing, and respiratory health. The aim of this review was to synthesise the evidence on the health effects of gaseous fuels to inform policies for scalable clean household energy. METHODS: In this systematic review and meta-analysis, we summarised the health effects from cooking or heating with gas compared with polluting fuels (eg, wood or charcoal) and clean energy (eg, electricity and solar energy). We searched PubMed, Scopus, Web of Science, MEDLINE, Cochrane Library (CENTRAL), Environment Complete, GreenFile, Google Scholar, Wanfang DATA, and CNKI for articles published between Dec 16, 2020, and Feb 6, 2021. Studies eligible for inclusion had to compare gas for cooking or heating with polluting fuels (eg, wood or charcoal) or clean energy (eg, electricity or solar energy) and present data for health outcomes in general populations. Studies that reported health outcomes that were exacerbations of existing underlying conditions were excluded. Several of our reviewers were involved in screening studies, data extraction, and quality assessment (including risk of bias) of included studies; 20% of studies were independently screened, extracted and quality assessed by another reviewer. Disagreements were reconciled through discussion with the wider review team. Included studies were appraised for quality using the Liverpool Quality Assessment Tools. Key health outcomes were grouped for meta-analysis and analysed using Cochrane's RevMan software. Primary outcomes were health effects (eg, acute lower respiratory infections) and secondary outcomes were health symptoms (eg, respiratory symptoms such as wheeze, cough, or breathlessness). This study is registered with PROSPERO, CRD42021227092. FINDINGS: 116 studies were included in the meta-analysis (two [2%] randomised controlled trials, 13 [11%] case-control studies, 23 [20%] cohort studies, and 78 [67%] cross-sectional studies), contributing 215 effect estimates for five grouped health outcomes. Compared with polluting fuels, use of gas significantly lowered the risk of pneumonia (OR 0·54, 95% CI 0·38-0·77; p=0·00080), wheeze (OR 0·42, 0·30-0·59; p<0·0001), cough (OR 0·44, 0·32-0·62; p<0·0001), breathlessness (OR 0·40, 0·21-0·76; p=0·0052), chronic obstructive pulmonary disease (OR 0·37, 0·23-0·60; p<0·0001), bronchitis (OR 0·60, 0·43-0·82; p=0·0015), pulmonary function deficit (OR 0·27, 0·17-0·44; p<0·0001), severe respiratory illness or death (OR 0·27, 0·11-0·63; p=0·0024), preterm birth (OR 0·66, 0·45-0·97; p=0·033), and low birth weight (OR 0·70, 0·53-0·93; p=0·015). Non-statistically significant effects were observed for asthma in children (OR 1·04, 0·70-1·55; p=0·84), asthma in adults (OR 0·65, 0·43-1·00; p=0·052), and small for gestational age (OR 1·04, 0·89-1·21; p=0·62). Compared with electricity, use of gas significantly increased risk of pneumonia (OR 1·26, 1·03-1·53; p=0·025) and chronic obstructive pulmonary disease (OR 1·15, 1·06-1·25; p=0·0011), although smaller non-significant effects were observed for higher-quality studies. In addition, a small increased risk of asthma in children was not significant (OR 1·09, 0·99-1·19; p=0·071) and no significant associations were found for adult asthma, wheeze, cough, and breathlessness (p>0·05). A significant decreased risk of bronchitis was observed (OR 0·87, 0·81-0·93; p<0·0001). INTERPRETATION: Switching from polluting fuels to gaseous household fuels could lower health risk and associated morbidity and mortality in resource-poor countries where reliance on polluting fuels is greatest. Although gas fuel use was associated with a slightly higher risk for some health outcomes compared with electricity, gas is an important transitional option for health in countries where access to reliable electricity supply for cooking or heating is not feasible in the near term. FUNDING: WHO.

10.
J Midwifery Womens Health ; 69(1): 64-70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37358371

RESUMO

INTRODUCTION: Pregnancy is a major life event during which women may experience increased psychological distress and changes in eating behaviors. However, few studies have investigated the influence of psychological distress on pregnant women's eating behaviors. The primary objective of this prospective study was to examine the associations of changes in perceived stress and depressive symptoms with emotional eating and nutritional intake during pregnancy. In addition, we examined the direct and moderating effects of perceived social support. METHODS: Participants were racially diverse pregnant women (14-42 years) from 4 clinical sites in Detroit, MI, and Nashville, TN (N = 678). We used multiple linear and logistic regression models to determine if changes in stress and depressive symptoms across pregnancy were associated with changes in emotional eating and nutritional intake. We examined residualized change in stress and depressive symptoms from second to third trimester of pregnancy; positive residualized change scores indicated increased stress and depressive symptoms. RESULTS: Participants showed significant improvement in emotional eating and nutritional intake from second to third trimester of pregnancy (P < .001 for both). At second trimester, higher depressive symptoms were associated with a greater likelihood of emotional eating (P < .001) and worse nutritional intake (P = .044) at third trimester. Increased stress and depressive symptoms during pregnancy were both associated with increased risk, whereas increased perceived social support reduced risk of emotional eating at third trimester (stress: adjusted odds ratio [AOR], 1.17; 95% CI, 1.08-1.26; depressive symptoms: AOR, 1.05; 95% CI, 1.01-1.08; social support: AOR, 0.93; 95% CI, 0.88-0.99). None were associated with changes in nutritional intake. Perceived social support did not show any moderating effects. DISCUSSION: Increased psychological distress during pregnancy may increase emotional eating. Efforts to promote healthy eating behaviors among pregnant women should consider and address mental health.


Assuntos
Depressão , Emoções , Feminino , Gravidez , Humanos , Estudos Prospectivos , Ingestão de Alimentos/psicologia , Estresse Psicológico
11.
Otolaryngol Head Neck Surg ; 170(4): 1147-1157, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38104319

RESUMO

OBJECTIVE: Evaluate listening effort (LE) in unilateral, bilateral, and bimodal cochlear implant (CI) users. Establish an easy-to-implement task of LE that could be useful for clinical decision making. STUDY DESIGN: Prospective cohort study. SETTING: Tertiary neurotology center. METHODS: The Sentence Final Word Identification and Recall Task, an established measure of LE, was modified to include challenging listening conditions (multitalker babble, gender, and emotional variation; test), in addition to single-talker sentences (control). Participants listened to lists of sentences in each condition and recalled the last word of each sentence. LE was quantified by percentage of words correctly recalled and was compared across conditions, across CI groups, and within subjects (best aided vs monaural). RESULTS: A total of 24 adults between the ages of 37 and 82 years enrolled, including 4 unilateral CI users (CI), 10 bilateral CI users (CICI), and 10 bimodal CI users (CIHA). Task condition impacted LE (P < .001), but hearing configuration and listener group did not (P = .90). Working memory capacity and contralateral hearing contributed to individual performance. CONCLUSION: This study adds to the growing body of literature on LE in challenging listening conditions for CI users and demonstrates feasibility of a simple behavioral task that could be implemented clinically to assess LE. This study also highlights the potential benefits of bimodal hearing and individual hearing and cognitive factors in understanding individual differences in performance, which will be evaluated through further research.


Assuntos
Implante Coclear , Implantes Cocleares , Auxiliares de Audição , Percepção da Fala , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Esforço de Escuta , Estudos Prospectivos
12.
Sci Rep ; 13(1): 12748, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550419

RESUMO

It has been known for more than 160 years that highly occluded objects that would normally be visually unrecognizable can be successfully identified when they move. This anorthoscopic perception relies on the visual system's ability to integrate information over time to complete the perception of an entire object's shape. In this experiment, 16 younger and older adults (mean ages were 20.5 and 74.6 years, respectively) were familiarized with the (unoccluded) shapes of five naturally-shaped objects (bell peppers, Capsicum annuum) until they could be easily identified (i.e., with accuracies of at least 90 percent correct). All observers then viewed the stimulus objects anorthoscopically as they moved behind narrow slits; only small object fragments could be seen at any given time, because the objects were almost totally occluded from view. Even though the object identification performance for all observers was equivalent when whole object shapes were visible, a large age-related deficit in object identification emerged during anorthoscopic viewing such that the younger adults' identification performance was 45.4 percent higher than that of the older adults. This first ever study of aging and anorthoscopic perception demonstrates that there is an age-related deficit in performing the temporal integration needed for successful object recognition.


Assuntos
Percepção Visual , Humanos , Adulto Jovem , Idoso , Capsicum , Percepção de Forma
13.
Pediatr Neurol ; 147: 56-62, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37556940

RESUMO

BACKGROUND: Selective dorsal rhizotomy (SDR) is a surgical procedure that permanently alters lower extremity spasticity, common in children with spastic cerebral palsy (CP). Intensive postoperative physical therapy (PT) is recommended following SDR. The first purpose of this study is to describe and compare patient demographics between children who received SDR and the population of children with CP at one institution. The second purpose of this study is to compare the completed dose of postoperative PT with the clinically recommended dose for a subset of ambulatory children who underwent SDR. METHODS: This retrospective, observational study included 60 children with spastic CP following SDR. A subset (n = 12 ambulatory children) was included to describe the dose of postoperative PT. Information gathered from electronic medical records included age at the time of SDR, sex, Gross Motor Function Classification System level, anatomic distribution, race, county-level habitancy, health insurance provider, timed current procedural terminology codes, and location for postoperative PT encounters within a single institution. RESULTS: Black or African American children (P = 0.002), children living in large central metro areas (P = 0.033), and children with public insurance (P ≤ 0.001) were significantly less likely to receive SDR. Children undergoing SDR do not achieve the recommended dose of PT after hospital discharge. CONCLUSION: SDR is not equally accessed by patient populations, and postoperative PT frequency is below current recommendations throughout the rehabilitation process. Future studies need to investigate why these disparities exist and what prevents children from meeting the clinically recommended dose of postoperative PT after SDR.


Assuntos
Paralisia Cerebral , Rizotomia , Criança , Humanos , Rizotomia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Espasticidade Muscular/cirurgia , Modalidades de Fisioterapia , Demografia
14.
mBio ; 14(5): e0141623, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37589464

RESUMO

IMPORTANCE: As deficiencies in tRNA modifications have been linked to human diseases such as cancer and diabetes, much research has focused on the modifications' impacts on translational regulation in eukaryotes. However, the significance of tRNA modifications in bacterial physiology remains largely unexplored. In this paper, we demonstrate that the m7G tRNA methyltransferase TrmB is crucial for a top-priority pathogen, Acinetobacter baumannii, to respond to stressors encountered during infection, including oxidative stress, low pH, and iron deprivation. We show that loss of TrmB dramatically attenuates a murine pulmonary infection. Given the current efforts to use another tRNA methyltransferase, TrmD, as an antimicrobial therapeutic target, we propose that TrmB, and other tRNA methyltransferases, may also be viable options for drug development to combat multidrug-resistant A. baumannii.


Assuntos
Acinetobacter baumannii , Pneumonia , Animais , Humanos , Camundongos , Acinetobacter baumannii/metabolismo , Acinetobacter baumannii/patogenicidade , Farmacorresistência Bacteriana Múltipla/genética , Estresse Oxidativo , Pneumonia/microbiologia , Pneumonia/patologia , RNA de Transferência/genética , RNA de Transferência/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
16.
J Virol ; 97(7): e0066723, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37310294

RESUMO

Receptor-binding proteins (RBPs) allow phages to dock onto their host and initiate infection through the recognition of proteinaceous or saccharidic receptors located on the cell surface. FhuA is the ferrichrome hydroxamate transporter in Escherichia coli and serves as a receptor for the well-characterized phages T1, T5, and phi80. To further characterize how other FhuA-dependent phages attach to FhuA, we isolated and published the genomes of three new FhuA-dependent coliphages: JLBYU37, JLBYU41, and JLBYU60. We identified the egions of FhuA involved in phage attachment by testing the effect of mutant fhuA alleles containing single-loop deletions of extracellular loops (L3, L4, L5, L8, L10, and L11) on phage infectivity. Deletion of loop 8 resulted in complete resistance to SO1-like phages JLBYU37 and JLBYU60 and the previously isolated vB_EcoD_Teewinot phage, but no single-loop deletions significantly altered the infection of T1-like JLBYU41. Additionally, lipopolysaccharide (LPS) truncation coupled with the L5 mutant significantly impaired the infectivity of JLBYU37 and JLBYU60. Moreover, significant reductions in the infectivity of JLBYU41 were observed upon LPS truncation in the L8 mutant strain. Analysis of the evolutionary relationships among FhuA-dependent phage RBPs highlights the conservation of L8 dependence in JLBYU37, JLBYU60, Teewinot, T5, and phi80, but also showcases how positive selective pressure and/or homologous recombination also selected for L4 dependence in T1 and even the lack of complete loop dependence in JLBYU41. IMPORTANCE Phage attachment is the first step of phage infection and plays a role in governing host specificity. Characterizing the interactions taking place between phage tail fibers and bacterial receptors that better equip bacteria to survive within the human body may provide insights to aid the development of phage therapeutics.


Assuntos
Bacteriófagos , Proteínas de Escherichia coli , Humanos , Proteínas de Escherichia coli/química , Proteínas de Bactérias/metabolismo , Ferricromo/metabolismo , Ferricromo/farmacologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Lipopolissacarídeos/metabolismo , Receptores Virais/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Colífagos/genética , Colífagos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Bacteriófagos/genética , Bacteriófagos/metabolismo
17.
AIDS Res Ther ; 20(1): 25, 2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-37150823

RESUMO

BACKGROUND: Behavioral economic (BE) biases have been studied in the context of numerous health conditions, yet are understudied in the field of HIV prevention. This aim of this study was to quantify the prevalence of four common BE biases-present bias, information salience, overoptimism, and loss aversion-relating to condom use and HIV testing in economically-vulnerable young adults who had increased likelihood of acquiring HIV. We also qualitatively examined participants' perceptions of these biases. METHODS: 43 participants were enrolled in the study. Data were collected via interviews using a quantitative survey instrument embedded with qualitative questions to characterize responses. Interviews were transcribed and analyzed using descriptive statistics and deductive-inductive content analyses. RESULTS: 56% of participants were present-biased, disproportionately discounting future rewards for smaller immediate rewards. 51% stated they were more likely to spend than save given financial need. Present-bias relating to condom use was lower with 28% reporting they would engage in condomless sex rather than wait one day to access condoms. Most participants (72%) were willing to wait for condom-supported sex given the risk. Only 35% knew someone living with HIV, but 67% knew someone who had taken an HIV test, and 74% said they often think about preventing HIV (e.g., high salience). Yet, 47% reported optimistically planning for condom use, HIV discussions with partners, or testing but failing to stick to their decision. Most (98%) were also averse (b = 9.4, SD ±.9) to losing their HIV-negative status. Qualitative reasons for sub-optimal condom or testing choices were having already waited to find a sex partner, feeling awkward, having fear, or not remembering one's plan in the moment. Optimal decisions were attributed qualitatively to self-protective thoughts, establishing routine care, standing on one's own, and thinking of someone adversely impacted by HIV. 44% of participants preferred delayed monetary awards (e.g., future-biased), attributed qualitatively to fears of spending immediate money unwisely or needing time to plan. CONCLUSION: Mixed methods BE assessments may be a valuable tool in understanding factors contributing to optimal and sub-optimal HIV prevention decisions. Future HIV prevention interventions may benefit from integrating savings products, loss framing, commitment contracts, cues, or incentives.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Adulto Jovem , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Economia Comportamental , Baltimore , Preservativos , Comportamento Sexual
18.
Nat Commun ; 14(1): 1927, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37045819

RESUMO

Cancer cells exhibit elevated lipid synthesis. In breast and other cancer types, genes involved in lipid production are highly upregulated, but the mechanisms that control their expression remain poorly understood. Using integrated transcriptomic, lipidomic, and molecular studies, here we report that DAXX is a regulator of oncogenic lipogenesis. DAXX depletion attenuates, while its overexpression enhances, lipogenic gene expression, lipogenesis, and tumor growth. Mechanistically, DAXX interacts with SREBP1 and SREBP2 and activates SREBP-mediated transcription. DAXX associates with lipogenic gene promoters through SREBPs. Underscoring the critical roles for the DAXX-SREBP interaction for lipogenesis, SREBP2 knockdown attenuates tumor growth in cells with DAXX overexpression, and DAXX mutants unable to bind SREBP1/2 have weakened activity in promoting lipogenesis and tumor growth. Remarkably, a DAXX mutant deficient of SUMO-binding fails to activate SREBP1/2 and lipogenesis due to impaired SREBP binding and chromatin recruitment and is defective of stimulating tumorigenesis. Hence, DAXX's SUMO-binding activity is critical to oncogenic lipogenesis. Notably, a peptide corresponding to DAXX's C-terminal SUMO-interacting motif (SIM2) is cell-membrane permeable, disrupts the DAXX-SREBP1/2 interactions, and inhibits lipogenesis and tumor growth. These results establish DAXX as a regulator of lipogenesis and a potential therapeutic target for cancer therapy.


Assuntos
Lipogênese , Neoplasias , Carcinogênese/genética , Transformação Celular Neoplásica , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Lipídeos , Lipogênese/genética , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Camundongos
19.
J Proteome Res ; 22(6): 1762-1778, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36995114

RESUMO

The process of O-linked protein glycosylation is highly conserved across the Burkholderia genus and mediated by the oligosaccharyltransferase PglL. While our understanding of Burkholderia glycoproteomes has increased in recent years, little is known about how Burkholderia species respond to modulations in glycosylation. Utilizing CRISPR interference (CRISPRi), we explored the impact of silencing of O-linked glycosylation across four species of Burkholderia; Burkholderia cenocepacia K56-2, Burkholderia diffusa MSMB375, Burkholderia multivorans ATCC17616, and Burkholderia thailandensis E264. Proteomic and glycoproteomic analyses revealed that while CRISPRi enabled inducible silencing of PglL, this did not abolish glycosylation, nor recapitulate phenotypes such as proteome changes or alterations in motility that are associated with glycosylation null strains, despite inhibition of glycosylation by nearly 90%. Importantly, this work also demonstrated that CRISPRi induction with high levels of rhamnose leads to extensive impacts on the Burkholderia proteomes, which without appropriate controls mask the impacts specifically driven by CRISPRi guides. Combined, this work revealed that while CRISPRi allows the modulation of O-linked glycosylation with reductions up to 90% at a phenotypic and proteome levels, Burkholderia appears to demonstrate a robust tolerance to fluctuations in glycosylation capacity.


Assuntos
Burkholderia , Proteoma , Glicosilação , Proteoma/genética , Proteoma/metabolismo , Proteômica , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Burkholderia/genética , Burkholderia/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-38248505

RESUMO

Pregnancy carries substantial risk for developing lower urinary tract symptoms (LUTSs), with potential lifelong impacts on bladder health. Little is known about modifiable psychosocial factors that may influence the risk of postpartum LUTSs. We examined associations between depressive symptoms, perceived stress, and postpartum LUTSs, and the moderating effects of perceived social support, using data from a cohort study of Expect With Me group prenatal care (n = 462). One year postpartum, 40.3% participants reported one or more LUTS. The most frequent LUTS was daytime frequency (22.3%), followed by urinary incontinence (19.5%), urgency (18.0%), nocturia (15.6%), and bladder pain (6.9%). Higher odds of any LUTS were associated with greater depressive symptoms (adjusted odds ratio (AOR) 1.08, 95% confidence interval (CI) 1.04-1.11) and perceived stress (AOR 1.12, 95% CI 1.04-1.19). Higher perceived social support was associated with lower odds of any LUTS (AOR 0.94, 95% CI 0.88-0.99). Perceived social support mitigated the adverse effects of depressive symptoms (interaction AOR 0.99, 95% CI 0.98-0.99) and perceived stress (interaction AOR 0.97, 95% CI 0.95-0.99) on experiencing any LUTS. Greater depressive symptoms and perceived stress may increase the likelihood of experiencing LUTSs after childbirth. Efforts to promote bladder health among postpartum patients should consider psychological factors and social support.


Assuntos
Sintomas do Trato Urinário Inferior , Incontinência Urinária , Feminino , Gravidez , Humanos , Estudos de Coortes , Período Pós-Parto , Sintomas do Trato Urinário Inferior/epidemiologia , Parto , Luteína
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