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1.
J Bacteriol ; : e0008724, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771039

RESUMO

Bacterial meningitis is a life-threatening infection of the central nervous system (CNS) that occurs when bacteria are able to cross the blood-brain barrier (BBB) or the meningeal-cerebrospinal fluid barrier (mBCSFB). The BBB and mBCSFB comprise highly specialized brain endothelial cells (BECs) that typically restrict pathogen entry. Group B Streptococcus (GBS or Streptococcus agalactiae) is the leading cause of neonatal meningitis. Until recently, identification of GBS virulence factors has relied on genetic screening approaches. Instead, we here conducted RNA-seq analysis on GBS when interacting with induced pluripotent stem cell-derived BECs (iBECs) to pinpoint virulence-associated genes. Of the 2,068 annotated protein-coding genes of GBS, 430 transcripts displayed significant changes in expression after interacting with BECs. Notably, we found that the majority of differentially expressed GBS transcripts were downregulated (360 genes) during infection of iBECs. Interestingly, codY, encoding a pleiotropic transcriptional repressor in low-G + C Gram-positive bacteria, was identified as being highly downregulated. We conducted qPCR to confirm the codY downregulation observed via RNA-seq during the GBS-iBEC interaction and obtained codY mutants in three different GBS background parental strains. As anticipated from the RNA-seq results, the [Formula: see text]codY strains were more adherent and invasive in two in vitro BEC models. Together, this demonstrates the utility of RNA-seq during the BEC interaction to identify GBS virulence modulators. IMPORTANCE: Group B Streptococcus (GBS) meningitis remains the leading cause of neonatal meningitis. Research work has identified surface factors and two-component systems that contribute to GBS disruption of the blood-brain barrier (BBB). These discoveries often relied on genetic screening approaches. Here, we provide transcriptomic data describing how GBS changes its transcriptome when interacting with brain endothelial cells. Additionally, we have phenotypically validated these data by obtaining mutants of a select regulator that is highly down-regulated during infection and testing on our BBB model. This work provides the research field with a validated data set that can provide an insight into potential pathways that GBS requires to interact with the BBB and open the door to new discoveries.

2.
bioRxiv ; 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38370636

RESUMO

IgE-mediated stimulation of monocytes regulates multiple cellular functions including cellular maturation, cytokine release, antiviral responses, and T cell priming and differentiation. The high affinity IgE receptor, FcεRI, is closely linked to serum IgE levels and atopic disease. The signaling molecules which regulate effector functions of this receptor have been well studied in mast cells and basophils, however, less is known about the signaling components, regulatory molecules, and mechanisms downstream of receptor activation in monocytes. This study sought to identify regulators of IgE-mediated cytokine release in human monocytes. SHIP-1 was identified as a negative regulator of IgE-induced IL-10 production. It was also determined that IgE-mediated stimulation and SHIP-1 inhibition decreased antiviral IP-10 production after liposomal poly(I:C) stimulation, indicating differential regulation by SHIP-1 in IgE-driven and antiviral response pathways. Both SHIP-1 and NF-κB were activated following IgE-mediated stimulation of primary monocytes, and NF-κB activation was related to both SHIP-1 and FcεRIα expression levels in monocytes. To our knowledge this is the first study to identify a role for SHIP-1 in regulating IgE-driven responses and antiviral responses in human monocytes. Given the importance of monocytes in inflammation and immune responses, a better understanding of the signaling and regulatory mechanisms downstream of FcεRI receptor could lead to new therapeutic targets in allergic disease.

3.
Physiol Rep ; 12(3): e15943, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38311364

RESUMO

Inspiratory resistance training (IRT) yields significant reductions in resting blood pressure and improves vascular endothelial function. Our objective was to quantify the acute effects of IRT on brachial artery flow-mediated dilation (FMD) and shear rates (SRs) in healthy men and women. Twenty young adults (22.9 ± 3.4 years; 10 male, 10 female) completed a single bout of IRT or Rest condition in a randomized crossover design. Brachial artery FMD was performed before, 10 min after, and 40 min after the assigned condition. Brachial artery blood flow velocities were collected during IRT, separated by breathing cycle phase, and converted into SRs. FMD improved 10 min post-IRT (+1.86 ± 0.61%; p = 0.025) but returned to baseline by 40 min post-IRT (p = 0.002). Anterograde SR decreased by 10% and retrograde SR increased 102% during resisted inspiration, relative to baseline SR (p < 0.001). Anterograde SR increased by 7% in men and women (p < 0.001) and retrograde SR decreased by 12% in women but not men (p = 0.022) during unresisted expiration, relative to baseline SR. A single bout of IRT elicits a transient enhancement in FMD in both men and women. Acute IRT-related enhancements in SRs may contribute to sustained improvements in FMD that have been reported previously.


Assuntos
Treinamento Resistido , Vasodilatação , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Velocidade do Fluxo Sanguíneo/fisiologia , Artéria Braquial/fisiologia , Estudos Cross-Over , Dilatação , Endotélio Vascular/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Estresse Mecânico , Vasodilatação/fisiologia
4.
Med Sci Sports Exerc ; 56(2): 266-276, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707508

RESUMO

PURPOSE: This study aimed to determine if time-efficient, high-resistance inspiratory muscle strength training (IMST), comprising 30 inhalation-resisted breaths per day, improves cardiorespiratory fitness, exercise tolerance, physical function, and/or regional body composition in healthy midlife and older adults. METHODS: We performed a double-blind, randomized, sham-controlled clinical trial (NCT03266510) testing 6 wk of IMST (30 breaths per day, 6 d·wk -1 , 55%-75% maximal inspiratory pressure) versus low-resistance sham training (15% maximal inspiratory pressure) in healthy men and women 50-79 yr old. Subjects performed a graded treadmill exercise test to exhaustion, physical performance battery (e.g., handgrip strength, leg press), and body composition testing (dual x-ray absorptiometry) at baseline and after 6 wk of training. RESULTS: Thirty-five participants (17 women, 18 men) completed high-resistance IMST ( n = 17) or sham training ( n = 18). Cardiorespiratory fitness (V̇O 2peak ) was unchanged, but exercise tolerance, measured as treadmill exercise time during a graded exercise treadmill test, increased with IMST (baseline, 539 ± 42 s; end intervention, 606 ± 42 s; P = 0.01) but not sham training (baseline, 562 ± 39 s; end intervention, 553 ± 38 s; P = 0.69). IMST increased peak RER (baseline, 1.09 ± 0.02; end intervention, 1.13 ± 0.02; P = 0.012), peak ventilatory efficiency (baseline, 25.2 ± 0.8; end intervention, 24.6 ± 0.8; P = 0.036), and improved submaximal exercise economy (baseline, 23.5 ± 1.1 mL·kg -1 ⋅min -1 ; end intervention, 22.1 ± 1.1 mL·kg -1 ⋅min -1 ; P < 0.001); none of these factors were altered by sham training (all P > 0.05). Changes in plasma acylcarnitines (targeted metabolomics analysis) were consistently positively correlated with changes in exercise tolerance after IMST but not sham training. IMST was associated with regional increases in thorax lean mass (+4.4%, P = 0.06) and reductions in trunk fat mass (-4.8%, P = 0.04); however, peripheral muscle strength, muscle power, dexterity, and mobility were unchanged. CONCLUSIONS: These data suggest that high-resistance IMST is an effective, time-efficient lifestyle intervention for improving exercise tolerance in healthy midlife and older adults.


Assuntos
Tolerância ao Exercício , Treinamento Resistido , Idoso , Feminino , Humanos , Masculino , Força da Mão , Força Muscular/fisiologia , Músculos , Terapia Respiratória , Método Duplo-Cego
5.
J Arthroplasty ; 39(4): 979-984.e3, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37923233

RESUMO

BACKGROUND: The incidence of total hip arthroplasty (THA) in the United States continues to increase due to its ability to markedly improve patients' quality of life. This study investigated and compared the perioperative and postoperative outcomes of simultaneous (SI-THA) and staged (ST-THA) bilateral THA procedures using an anterior-based muscle-sparing (ABMS) approach. METHODS: This retrospective case control study evaluated perioperative and postoperative outcomes from primary bilateral SI-THA or ST-THA (within 365 days) performed with the ABMS approach by 3 surgeons at a single institution between January 2013 and August 2020. A total of 226 patients (113 in each cohort) were matched based on age, sex, body mass index, and comorbidity score. RESULTS: Compared to the ST-THA group, the SI-THA had shorter anesthesia duration (P < .001) and shorter length of stay (P < .001), but longer length of surgery (P = .002). There was no statistical significance between groups in blood transfusion rates, discharge dispositions, emergency department visits, hospital readmissions, or postoperative complications within one year. CONCLUSIONS: The results of this study demonstrate that SI-THA and ST-THA yield comparable results using the ABMS approach. Our perioperative and postoperative results suggest low rates of complications, emergency department visits, readmissions, and high rates of patient satisfaction scores. Therefore, both SI-THA and ST-THA can be considered by experienced surgeons as treatment for advanced bilateral hip arthritis.


Assuntos
Artroplastia de Quadril , Humanos , Artroplastia de Quadril/efeitos adversos , Estudos Retrospectivos , Estudos de Casos e Controles , Qualidade de Vida , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Músculos
6.
NPJ Vaccines ; 8(1): 172, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932282

RESUMO

The flavivirus envelope protein is a class II fusion protein that drives flavivirus-cell membrane fusion. The membrane fusion process is triggered by the conformational change of the E protein from dimer in the virion to trimer, which involves the rearrangement of three domains, EDI, EDII, and EDIII. The movement between EDI and EDII initiates the formation of the E protein trimer. The EDI-EDII hinge region utilizes four motifs to exert the hinge effect at the interdomain region and is crucial for the membrane fusion activity of the E protein. Using West Nile virus (WNV) NY99 strain derived from an infectious clone, we investigated the role of eight flavivirus-conserved hydrophobic residues in the EDI-EDII hinge region in the conformational change of E protein from dimer to trimer and viral entry. Single mutations of the E-A54, E-I130, E-I135, E-I196, and E-Y201 residues affected infectivity. Importantly, the E-A54I and E-Y201P mutations fully attenuated the mouse neuroinvasive phenotype of WNV. The results suggest that multiple flavivirus-conserved hydrophobic residues in the EDI-EDII hinge region play a critical role in the structure-function of the E protein and some contribute to the virulence phenotype of flaviviruses as demonstrated by the attenuation of the mouse neuroinvasive phenotype of WNV. Thus, as a proof of concept, residues in the EDI-EDII hinge region are proposed targets to engineer attenuating mutations for inclusion in the rational design of candidate live-attenuated flavivirus vaccines.

7.
Am J Physiol Heart Circ Physiol ; 325(5): H1059-H1068, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37682232

RESUMO

Aging is associated with increased risk for cognitive decline and dementia due in part to increases in systolic blood pressure (SBP) and cerebrovascular dysfunction. High-resistance inspiratory muscle strength training (IMST) is a time-efficient, intensive respiratory training protocol (30 resisted inspirations/day) that lowers SBP and improves peripheral vascular function in midlife/older adults with above-normal SBP. However, whether, and by what mechanisms, IMST can improve cerebrovascular function is unknown. We hypothesized that IMST would increase cerebrovascular reactivity to hypercapnia (CVR to CO2), which would coincide with changes to the plasma milieu that improve brain endothelial cell function and enhance cognitive performance (NIH Toolbox). We conducted a 6-wk double-blind, randomized, controlled clinical trial investigating high-resistance IMST [75% maximal inspiratory pressure (PImax); 6×/wk; 4 females, 5 males] vs. low-resistance sham training (15% PImax; 6×/wk; 2 females, 5 males) in midlife/older adults (age 50-79 yr) with initial above-normal SBP. Human brain endothelial cells (HBECs) were exposed to participant plasma and assessed for acetylcholine-stimulated nitric oxide (NO) production. CVR to CO2 increased after high-resistance IMST (pre: 1.38 ± 0.66 cm/s/mmHg; post: 2.31 ± 1.02 cm/s/mmHg, P = 0.020). Acetylcholine-stimulated NO production increased in HBECs exposed to plasma from after vs. before the IMST intervention [pre: 1.49 ± 0.33; post: 1.73 ± 0.35 arbitrary units (AU); P < 0.001]. Episodic memory increased modestly after the IMST intervention (pre: 95 ± 13; post: 103 ± 17 AU; P = 0.045). Cerebrovascular and cognitive function were unchanged in the sham control group. High-resistance IMST may be a promising strategy to improve cerebrovascular and cognitive function in midlife/older adults with above-normal SBP, a population at risk for future cognitive decline and dementia.NEW & NOTEWORTHY Midlife/older adults with above-normal blood pressure are at increased risk of developing cognitive decline and dementia. Our findings suggest that high-resistance inspiratory muscle strength training (IMST), a novel, time-efficient (5-10 min/day) form of physical training, may increase cerebrovascular reactivity to CO2 and episodic memory in midlife/older adults with initial above-normal blood pressure.


Assuntos
Demência , Treinamento Resistido , Masculino , Feminino , Humanos , Idoso , Pessoa de Meia-Idade , Dióxido de Carbono , Acetilcolina , Células Endoteliais , Músculos Respiratórios/fisiologia , Força Muscular/fisiologia
8.
Food Chem Toxicol ; 179: 113980, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37549805

RESUMO

Cetylpyridinium chloride (CPC) is an antimicrobial used in numerous personal care and janitorial products and food for human consumption at millimolar concentrations. Minimal information exists on the eukaryotic toxicology of CPC. We have investigated the effects of CPC on signal transduction of the immune cell type mast cells. Here, we show that CPC inhibits the mast cell function degranulation with antigen dose-dependence and at non-cytotoxic doses ∼1000-fold lower than concentrations in consumer products. Previously we showed that CPC disrupts phosphatidylinositol 4,5-bisphosphate, a signaling lipid critical for store-operated Ca2+ entry (SOCE), which mediates degranulation. Our results indicate that CPC inhibits antigen-stimulated SOCE: CPC restricts Ca2+ efflux from endoplasmic reticulum, reduces Ca2+ uptake into mitochondria, and dampens Ca2+ flow through plasma membrane channels. While inhibition of Ca2+ channel function can be caused by alteration of plasma membrane potential (PMP) and cytosolic pH, CPC does not affect PMP or pH. Inhibition of SOCE is known to depress microtubule polymerization, and here we show that CPC indeed dose-dependently shuts down formation of microtubule tracks. In vitro data reveal that CPC inhibition of microtubules is not due to direct CPC interference with tubulin. In summary, CPC is a signaling toxicant that targets Ca2+ mobilization.


Assuntos
Cetilpiridínio , Mastócitos , Humanos , Cetilpiridínio/metabolismo , Cetilpiridínio/farmacologia , Cálcio/metabolismo , Transdução de Sinais , Preparações Farmacêuticas/metabolismo , Sinalização do Cálcio
9.
bioRxiv ; 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37292883

RESUMO

Cetylpyridinium chloride (CPC) is an antimicrobial used in numerous personal care and janitorial products and food for human consumption at millimolar concentrations. Minimal information exists on the eukaryotic toxicology of CPC. We have investigated the effects of CPC on signal transduction of the immune cell type mast cells. Here, we show that CPC inhibits the mast cell function degranulation with antigen dose-dependence and at non-cytotoxic doses ∼1000-fold lower than concentrations in consumer products. Previously we showed that CPC disrupts phosphatidylinositol 4,5-bisphosphate, a signaling lipid critical for store-operated Ca 2+ entry (SOCE), which mediates degranulation. Our results indicate that CPC inhibits antigen-stimulated SOCE: CPC restricts Ca 2+ efflux from endoplasmic reticulum, reduces Ca 2+ uptake into mitochondria, and dampens Ca 2+ flow through plasma membrane channels. While inhibition of Ca 2+ channel function can be caused by alteration of plasma membrane potential (PMP) and cytosolic pH, CPC does not affect PMP or pH. Inhibition of SOCE is known to depress microtubule polymerization, and here we show that CPC indeed dose-dependently shuts down formation of microtubule tracks. In vitro data reveal that CPC inhibition of microtubules is not due to direct CPC interference with tubulin. In summary, CPC is a signaling toxicant that targets Ca 2+ mobilization.

10.
J Surg Res ; 290: 241-246, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301176

RESUMO

INTRODUCTION: The COVID-19 pandemic necessitated an exclusively virtual 2021 residency application cycle. We hypothesized that residency programs' online presence would have increased utility and influence for applicants. METHODS: Substantial surgery residency website modifications were undertaken in the summer of 2020. Page views were gathered by our institution's information technology office for comparison across years and programs. An anonymous, voluntary, online survey was sent to all interviewed applicants for our 2021 general surgery program match. Five-point Likert-scale questions evaluated applicants' perspective on the online experience. RESULTS: Our residency website received 10,650 page views in 2019 and 12,688 in 2020 (P = 0.14). Page views increased with a greater margin compared to a different specialty residency program's (P < 0.01). From 108 interviewees, 75 completed the survey (69.4%). Respondents indicated our website was satisfactory or very satisfactory compared to other programs (83.9%), and none found it unsatisfactory. Applicants overall stated our institution's online presence impacted their decision to interview (51.6%). Programs' online presence impacted the decision to interview for nonWhite applicants (68%) but significantly less for white applicants (31%, P < 0.03). We observed a trend that those with fewer than this cohort's median interviews (17 or less) put more weight on online presence (65%), compared to those with 18 or greater interviews (35%). CONCLUSIONS: Applicants utilized program websites more during the 2021 virtual application cycle; our data show most applicants depend on institutions' websites to supplement their decision-making; however, there are subgroup differences in the influence online presence has on applicant decisions. Efforts to enhance residency webpages and online resources for candidates may positively influence prospective surgical trainees, and especially those underrepresented in medicine, to decide to interview.


Assuntos
COVID-19 , Internato e Residência , Humanos , Estudos Prospectivos , Pandemias , COVID-19/epidemiologia , Inquéritos e Questionários
11.
Clin Microbiol Infect ; 29(10): 1335.e9-1335.e16, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37364635

RESUMO

OBJECTIVES: Mycobacterium abscessus complex is responsible for 2.6-13.0% of all non-tuberculous mycobacterial pulmonary infections and these are notoriously difficult to treat due to the complex regimens required, drug resistance and adverse effects. Hence, bacteriophages have been considered in clinical practice as an additional treatment option. Here, we evaluated antibiotic and phage susceptibility profiles of M. abscessus clinical isolates. Whole-genome sequencing (WGS) revealed the phylogenetic relationships, dominant circulating clones (DCCs), the likelihood of patient-to-patient transmission and the presence of prophages. METHODS: Antibiotic susceptibility testing was performed using CLSI breakpoints (n = 95), and plaque assays were used for phage susceptibility testing (subset of n = 88, 35 rough and 53 smooth morphology). WGS was completed using the Illumina platform and analysed using Snippy/snp-dists and Discovery and Extraction of Phages Tool (DEPhT). RESULTS: Amikacin and Tigecycline were the most active drugs (with 2 strains resistant to amikacin, and one strain with Tigecycline MIC of 4 µg/mL). Most strains were resistant to all other drugs tested, with Linezolid and Imipenem showing the least resistance, at 38% (36/95) and 55% (52/95), respectively. Rough colony morphotype strains were more phage-susceptible than smooth strains (77%-27/35 versus 48%-25/53 in the plaque assays, but smooth strains are not killed efficiently by those phages in liquid infection assay). We have also identified 100 resident prophages, some of which were propagated lytically. DCC1 (20%-18/90) and DCC4 (22%-20/90) were observed to be the major clones and WGS identified 6 events of possible patient-to-patient transmission. DISCUSSION: Many strains of M. abscessus complex are intrinsically resistant to available antibiotics and bacteriophages represent an alternative therapeutic option, but only for strains with rough morphology. Further studies are needed to elucidate the role of hospital-borne M. abscessus transmission.


Assuntos
Bacteriófagos , Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Humanos , Amicacina/farmacologia , Tigeciclina/uso terapêutico , Bacteriófagos/genética , Filogenia , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Resistência a Múltiplos Medicamentos , Atenção à Saúde , Testes de Sensibilidade Microbiana
12.
Endocrinology ; 164(6)2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37183548

RESUMO

The pituitary gland regulates growth, metabolism, reproduction, the stress response, uterine contractions, lactation, and water retention. It secretes hormones in response to hypothalamic input, end organ feedback, and diurnal cues. The mechanisms by which pituitary stem cells are recruited to proliferate, maintain quiescence, or differentiate into specific cell types, especially thyrotropes, are not well understood. We used single-cell RNA sequencing in juvenile P7 mouse pituitary cells to identify novel factors in pituitary cell populations, with a focus on thyrotropes and rare subtypes. We first observed cells coexpressing markers of both thyrotropes and gonadotropes, such as Pou1f1 and Nr5a1. This was validated in vivo by both immunohistochemistry and lineage tracing of thyrotropes derived from Nr5a1-Cre; mTmG mice and demonstrates that Nr5a1-progenitors give rise to a proportion of thyrotropes during development. Our data set also identifies novel factors expressed in pars distalis and pars tuberalis thyrotropes, including the Shox2b isoform in all thyrotropes and Sox14 specifically in Pou1f1-negative pars tuberalis thyrotropes. We have therefore used single-cell transcriptomics to determine a novel developmental trajectory for thyrotropes and potential novel regulators of thyrotrope populations.


Assuntos
Doenças da Hipófise , Adeno-Hipófise , Gravidez , Feminino , Camundongos , Animais , Tireotropina/metabolismo , Hipófise/metabolismo , Fatores de Transcrição/metabolismo , Doenças da Hipófise/metabolismo , Imuno-Histoquímica , Adeno-Hipófise/metabolismo , Fatores de Transcrição SOXB2/metabolismo
13.
Bone Jt Open ; 4(5): 299-305, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37128779

RESUMO

Obesity is associated with an increased risk of hip osteoarthritis, resulting in an increased number of total hip arthroplasties (THAs) performed annually. This study examines the peri- and postoperative outcomes of morbidly obese (MO) patients (BMI ≥ 40 kg/m2) compared to healthy weight (HW) patients (BMI 18.5 to < 25 kg/m2) who underwent a THA using the anterior-based muscle-sparing (ABMS) approach. This retrospective cohort study observes peri- and postoperative outcomes of MO and HW patients who underwent a primary, unilateral THA with the ABMS approach. Data from surgeries performed by three surgeons at a single institution was collected from January 2013 to August 2020 and analyzed using Microsoft Excel and Stata 17.0. This study compares 341 MO to 1,140 HW patients. Anaesthesia, surgery duration, and length of hospital stay was significantly lower in HW patients compared to MO. There was no difference in incidence of pulmonary embolism, periprosthetic fracture, or dislocation between the two groups. The rate of infection in MO patients (1.47%) was significantly higher than HW patients (0.14%). Preoperative patient-reported outcome measures (PROMs) show a significantly higher pain level in MO patients and a significantly lower score in functional abilities. Overall, six-week and one-year postoperative data show higher levels of pain, lower levels of functional improvement, and lower satisfaction scores in the MO group. The comorbidities of obesity are well studied; however, the implications of THA using the ABMS approach have not been studied. Our peri- and postoperative results demonstrate significant improvements in PROMs in MO patients undergoing THA. However, the incidence of deep infection was significantly higher in this group compared with HW patients.

14.
Biology (Basel) ; 12(4)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37106775

RESUMO

INTRODUCTION: Glioblastoma (GBM) is the most aggressive primary brain tumor in adults. Despite a growing understanding of glioblastoma pathology, the prognosis remains poor. METHODS: In this study, we used a previously extensively benchmarked algorithm to retrieve immune receptor (IR) recombination reads from GBM exome files available from the cancer genome atlas. The T-cell receptor complementarity determining region-3 (CDR3) amino acid sequences that represent the IR recombination reads were assessed and used for the generation of chemical complementarity scores (CSs) that represent potential binding interactions with cancer testis antigens (CTAs), which is an approach particularly suited to a big data setting. RESULTS: The electrostatic CSs representing the TRA and TRB CDR3s and the CTAs, SPAG9, GAGE12E, and GAGE12F, indicated that an increased electrostatic CS was associated with worse disease-free survival (DFS). We also assessed the RNA expression of immune marker genes, which indicated that a high-level expression of SPHK2 and CIITA genes also correlated with high CSs and worse DFS. Furthermore, apoptosis-related gene expression was revealed to be lower when the TCR CDR3-CTA electrostatic CSs were high. CONCLUSION: Adaptive IR recombination reads from exome files have the potential to aid in GBM prognoses and may provide opportunities to detect unproductive immune responses.

15.
BMC Genomics ; 24(1): 154, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36973666

RESUMO

BACKGROUND: High temperatures cause a suite of problems for cells, including protein unfolding and aggregation; increased membrane fluidity; and changes in DNA supercoiling, RNA stability, transcription and translation. Consequently, enhanced thermotolerance can evolve through an unknown number of genetic mechanisms even in the simple model bacterium Escherichia coli. To date, each E. coli study exploring this question resulted in a different set of mutations. To understand the changes that can arise when an organism evolves to grow at higher temperatures, we sequenced and analyzed two previously described E. coli strains, BM28 and BM28 ΔlysU, that have been laboratory adapted to the highest E. coli growth temperature reported to date. RESULTS: We found three large deletions in the BM28 and BM28 ΔlysU strains of 123, 15 and 8.5 kb in length and an expansion of IS10 elements. We found that BM28 and BM28 ΔlysU have considerably different genomes, suggesting that the BM28 culture that gave rise to BM28 and BM28 ΔlysU was a mixed population of genetically different cells. Consistent with published findings of high GroESL expression in BM28, we found that BM28 inexplicitly carries the groESL bearing plasmid pOF39 that was maintained simply by high-temperature selection pressure. We identified over 200 smaller insertions, deletions, single nucleotide polymorphisms and other mutations, including changes in master regulators such as the RNA polymerase and the transcriptional termination factor Rho. Importantly, this genome analysis demonstrates that the commonly cited findings that LysU plays a crucial role in thermotolerance and that GroESL hyper-expression is brought about by chromosomal mutations are based on a previous misinterpretation of the genotype of BM28. CONCLUSIONS: This whole-genome sequencing study describes genetically distinct mechanisms of thermotolerance evolution from those found in other heat-evolved E. coli strains. Studying adaptive laboratory evolution to heat in simple model organisms is important in the context of climate change. It is important to better understand genetic mechanisms of enhancing thermotolerance in bacteria and other organisms, both in terms of optimizing laboratory evolution methods for various organisms and in terms of potential genetic engineering of organisms most at risk or most important to our societies and ecosystems.


Assuntos
Escherichia coli , Temperatura Alta , Escherichia coli/genética , Escherichia coli/metabolismo , Ecossistema , Genoma Bacteriano , Engenharia Genética
16.
Clin Infect Dis ; 76(1): 103-112, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-35676823

RESUMO

BACKGROUND: Nontuberculous Mycobacterium infections, particularly Mycobacterium abscessus, are increasingly common among patients with cystic fibrosis and chronic bronchiectatic lung diseases. Treatment is challenging due to intrinsic antibiotic resistance. Bacteriophage therapy represents a potentially novel approach. Relatively few active lytic phages are available and there is great variation in phage susceptibilities among M. abscessus isolates, requiring personalized phage identification. METHODS: Mycobacterium isolates from 200 culture-positive patients with symptomatic disease were screened for phage susceptibilities. One or more lytic phages were identified for 55 isolates. Phages were administered intravenously, by aerosolization, or both to 20 patients on a compassionate use basis and patients were monitored for adverse reactions, clinical and microbiologic responses, the emergence of phage resistance, and phage neutralization in serum, sputum, or bronchoalveolar lavage fluid. RESULTS: No adverse reactions attributed to therapy were seen in any patient regardless of the pathogen, phages administered, or the route of delivery. Favorable clinical or microbiological responses were observed in 11 patients. Neutralizing antibodies were identified in serum after initiation of phage delivery intravenously in 8 patients, potentially contributing to lack of treatment response in 4 cases, but were not consistently associated with unfavorable responses in others. Eleven patients were treated with only a single phage, and no phage resistance was observed in any of these. CONCLUSIONS: Phage treatment of Mycobacterium infections is challenging due to the limited repertoire of therapeutically useful phages, but favorable clinical outcomes in patients lacking any other treatment options support continued development of adjunctive phage therapy for some mycobacterial infections.


Assuntos
Bacteriófagos , Fibrose Cística , Infecções por Mycobacterium não Tuberculosas , Mycobacterium , Terapia por Fagos , Humanos , Ensaios de Uso Compassivo , Preparações Farmacêuticas , Infecções por Mycobacterium não Tuberculosas/microbiologia , Fibrose Cística/microbiologia , Antibacterianos/uso terapêutico
17.
J Pharm Pract ; 36(1): 96-103, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34132129

RESUMO

PURPOSE: Controlled substances management is highly regulated, and requires institutions to have processes in place to maintain a closed-loop. This study was conducted to comprehensively evaluate the current state of controlled substances management, propose optimization opportunities, and implement steps to align the medication use process (MUP) to a defined desired state. METHODS: This evaluation was conducted in 2 phases. In phase 1, the current state of controlled substances management was assessed in order to develop a gap analysis tool and failure mode and effects analysis (FMEA). In phase 2, a work group was assembled to address opportunities within the FMEA. The work group prioritized opportunities using the risk priority number (RPN), and formulated action steps to align processes with the defined desired state. RESULTS: Through the literature evaluation, a desired state, consisting of 86 segments, was defined and compared with a gap analysis tool. Direct observation of the MUP allowed for development of 13 process maps depicting current state. Of the 86 segments, it was determined the study institution had a compliance rate of 62%. The remaining 38% correlated with 55 actionable process opportunities that were included in the FMEA. To date, 31 of the 55 (56%) opportunities have been successfully addressed by the work group. CONCLUSION: Use of direct observation to formulate a gap analysis tool and FMEA is an effective modality to evaluate controlled substances processes. These tools allow for pharmacy departments to identify and prioritize opportunities to optimize controlled substances management within an academic medication center.


Assuntos
Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Assistência Farmacêutica , Humanos , Gestão de Riscos , Substâncias Controladas , Centros Médicos Acadêmicos , Medição de Risco
18.
Respir Physiol Neurobiol ; 307: 103974, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36180018

RESUMO

Our objective was to evaluate the effects of 6-weeks high-resistance, low-volume inspiratory muscle strength training (IMST) on respiratory endurance, blood pressure (BP) and heart rate (HR) responsiveness to high respiratory workloads. Ten healthy young adults completed two constant-load resistive breathing tests to exhaustion (Tlim) (target pressure =65 % maximal inspiratory pressure [PImax]; duty cycle = 0.7; breathing frequency matched to eupnea) separated by 6-weeks high-resistance (75 % maximal inspiratory pressure, PImax), low-volume (30 inspiratory efforts/day, 5 days/week) IMST. Throughout resistive breathing trials we measured beat-to-beat changes in BP and HR, mouth pressure, inspiratory muscle work and perceived exertion. POST resistive breathing tests revealed significant gains in endurance (PRE: 362.0 ± 46.6 s vs. POST: 663.8 ± 110.3 s, p = 0.003) and increases in respiratory muscle work (PRE: -9445 ± 1562 mmHg.s vs. POST: -16648 ± 3761 mmHg.s, p = 0.069). Conversely, systolic and diastolic BP responses, HR and ratings of perceived exertion all declined. Consistent with previous observations, 6 weeks high resistance, low volume IMST lowered casual resting SBP (p = 0.002), DBP (p = 0.007) and mean arterial pressure (p = 0.001) and improved static inspiratory pressure. High resistance, low volume inspiratory muscle strength training extends respiratory endurance and attenuates BP responsiveness in healthy, recreationally-active young adults. The outcomes have implications for improved athletic performance and for attaining and/or maintaining cardiorespiratory fitness.


Assuntos
Exercícios Respiratórios , Aptidão Cardiorrespiratória , Adulto Jovem , Humanos , Músculos Respiratórios/fisiologia , Pulmão , Respiração
19.
bioRxiv ; 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38168155

RESUMO

Bacterial cells secrete extracellular vesicles (EVs), the function of which is a matter of intense investigation. Here, we show that the EVs secreted by the human pathogen Streptococcus pneumoniae (pneumococcus) are associated with bacterial DNA on their surface and can deliver this DNA to the transformation machinery of competent cells. These findings suggest that EVs contribute to gene transfer in Gram-positive bacteria, and in doing so, may promote the spread of drug resistance genes in the population.

20.
Br Dent J ; 233(10): 859, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36434226
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