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The advent of locus-specific protein recruitment technologies has enabled a new class of studies in chromatin biology. Epigenome editors (EEs) enable biochemical modifications of chromatin at almost any specific endogenous locus. Their locus-specificity unlocks unique information including the functional roles of distinct modifications at specific genomic loci. Given the growing interest in using these tools for biological and translational studies, there are many specific design considerations depending on the scientific question or clinical need. Here, we present and discuss important design considerations and challenges regarding the biochemical and locus specificities of epigenome editors. These include how to: account for the complex biochemical diversity of chromatin; control for potential interdependency of epigenome editors and their resultant modifications; avoid sequestration effects; quantify the locus specificity of epigenome editors; and improve locus-specificity by considering concentration, affinity, avidity, and sequestration effects.
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Cromatina , Edición Génica , Humanos , Cromatina/genética , Cromatina/metabolismo , Edición Génica/métodos , Epigenoma , Epigenómica/métodos , Epigénesis Genética , Sitios Genéticos , Animales , Sistemas CRISPR-CasRESUMEN
Cognitive or motor impairment is common among individuals with neurofibromatosis type 1 (NF1), an autosomal dominant tumor-predisposition disorder. As many as 70% of children with NF1 report difficulties with spatial/working memory, attention, executive function, and fine motor movements. In contrast to the utilization of various Nf1 mouse models, here we employ an NF1+/ex42del miniswine model to evaluate the mechanisms and characteristics of these presentations, taking advantage of a large animal species more like human anatomy and physiology. The prefrontal lobe, anterior cingulate, and hippocampus from NF1+/ex42del and wild-type miniswine were examined longitudinally, revealing abnormalities in mature oligodendrocytes and astrocytes, and microglial activation over time. Imbalances in GABA: Glutamate ratios and GAD67 expression were observed in the hippocampus and motor cortex, supporting the role of disruption in inhibitory neurotransmission in NF1 cognitive impairment and motor dysfunction. Moreover, NF1+/ex42del miniswine demonstrated slower and shorter steps, indicative of a balance-preserving response commonly observed in NF1 patients, and progressive memory and learning impairments. Collectively, our findings affirm the effectiveness of NF1+/ex42del miniswine as a valuable resource for assessing cognitive and motor impairments associated with NF1, investigating the involvement of specific neural circuits and glia in these processes, and evaluating potential therapeutic interventions.
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Modelos Animales de Enfermedad , Neurofibromatosis 1 , Animales , Neurofibromatosis 1/fisiopatología , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/metabolismo , Ratones , Neurofibromina 1/genética , Neurofibromina 1/metabolismo , Conducta Animal , Masculino , Hipocampo/patología , Hipocampo/metabolismo , Disfunción Cognitiva/etiología , Disfunción Cognitiva/fisiopatología , Oligodendroglía/metabolismo , Oligodendroglía/patología , Humanos , Astrocitos/metabolismo , Astrocitos/patología , FemeninoRESUMEN
Patients who speak languages other than English are frequently excluded from research. This exclusion exacerbates inequities, biases results, and may violate federal regulations and research ethics. Language justice is the right to communicate in an individual's preferred language to address power imbalances and promote equity. To promote language justice in research, we propose a method to translate and culturally-adapt multifaceted research materials into multiple languages simultaneously. Our method involves a multistep approach, including professional translation, review by bilingual expert panels to refine and reach consensus, and piloting or cognitive interviews with patients and families. Key differences from other translation approaches (eg, the World Health Organization) include omitting back-translation, given its limited utility in identifying translation challenges, and limiting expert panelist and piloting-participant numbers for feasibility. We detail a step-by-step approach to operationalizing this method and outline key considerations learned after utilizing this method to translate materials into 8 languages other than English for an ongoing multicenter pediatric research study on family safety-reporting. Materials included family brochures, surveys, and intervention materials. This approach took â¼6 months overall at a cost of <$2000 per language (not including study personnel costs). Key themes across the project included (1) tailor scope to timeline, budget, and resources, (2) thoughtfully design English source materials, (3) identify and apply guiding principles throughout the translation and editing process, and (4) carefully review content and formatting to account for nuances across multiple languages. This method balances feasibility and rigor in translating participant-facing materials into multiple languages simultaneously, advancing language justice in research.
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Multilingüismo , Humanos , Traducción , Investigación Biomédica/ética , NiñoRESUMEN
Bisphosphonates are commonly used to treat and prevent bone loss, but their effects in active, juvenile populations are unknown. This study examined the effects of intramuscular clodronate disodium (CLO) on bone turnover, serum bone biomarkers (SBB), bone mineral density (BMD), bone microstructure, biomechanical testing (BT), and cartilage glycosaminoglycan content (GAG) over 165 days. Forty juvenile sheep (253 ± 6 days of age) were divided into four groups: Control (saline), T0 (0.6 mg/kg CLO on day 0), T84 (0.6 mg/kg CLO on day 84), and T0+84 (0.6 mg/kg CLO on days 0 and 84). Sheep were exercised 4 days/week and underwent physical and lameness examinations every 14 days. Blood samples were collected for SBB every 28 days. Microstructure and BMD were calculated from tuber coxae (TC) biopsies (days 84 and 165) and bone healing was assessed by examining the prior biopsy site. BT and GAG were evaluated postmortem. Data, except lameness data, were analyzed using a mixed-effects model; lameness data were analyzed as ordinal data using a cumulative logistic model. CLO did not have any measurable effects on the skeleton of sheep. SBB showed changes over time (p ≤ 0.03), with increases in bone formation and decreases in some bone resorption markers. TC biopsies showed increasing bone volume fraction, trabecular spacing and thickness, and reduced trabecular number on day 165 versus day 84 (p ≤ 0.04). These changes may be attributed to exercise or growth. The absence of a treatment effect may be explained by the lower CLO dose used in large animals compared to humans. Further research is needed to examine whether low doses of bisphosphonates may be used in active juvenile populations for analgesia without evidence of bone changes.
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Ácido Clodrónico , Cojera Animal , Humanos , Animales , Ovinos , Ácido Clodrónico/farmacología , Cojera Animal/tratamiento farmacológico , Densidad Ósea , Difosfonatos/farmacología , Modelos AnimalesRESUMEN
BACKGROUND: Blood product component-only resuscitation (CORe) has been the standard of practice in both military and civilian trauma care with a 1:1:1 ratio used in attempt to recreate whole blood (WB) until recent data demonstrated WB to confer a survival advantage, leading to the emergence of WB as the contemporary resuscitation strategy of choice. Little is known about the cost and waste reduction associated with WB vs CORe. METHODS: This study is a retrospective single-center review of adult trauma patients admitted to a community trauma center who received WB or CORe as part of their massive transfusion protocol (MTP) resuscitation from 2017 to 2021. The WB group received a minimum of one unit WB while CORe received no WB. Univariate and multivariate analyses were completed. Statistical analysis was conducted using a 95% confidence level. Non-normally distributed, continuous data were analyzed using the Wilcoxon rank sum test. RESULTS: 576 patients were included (201 in WB and 375 in CORe). Whole blood conveyed a survival benefit vs CORe (OR 1.49 P < .05, 1.02-2.17). Whole blood use resulted in an overall reduction in products prepared (25.8%), volumes transfused (16.5%), product waste (38.7%), and MTP activation (56.3%). Cost savings were $849 923 annually and $3 399 693 over the study period. DISCUSSION: Despite increased patient volumes over the study period (43.7%), the utilization of WB as compared to CORe resulted in an overall $3.39 million cost savings while improving mortality. As such, we propose WB should be utilized in all resuscitation strategies for the exsanguinating trauma patient.
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Transfusión de Componentes Sanguíneos , Transfusión Sanguínea , Ahorro de Costo , Resucitación , Centros Traumatológicos , Humanos , Centros Traumatológicos/economía , Estudios Retrospectivos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Transfusión Sanguínea/economía , Transfusión Sanguínea/estadística & datos numéricos , Resucitación/economía , Resucitación/métodos , Transfusión de Componentes Sanguíneos/economía , Transfusión de Componentes Sanguíneos/estadística & datos numéricos , Heridas y Lesiones/terapia , Heridas y Lesiones/economíaRESUMEN
Small molecule inhibitors of the mitochondrial electron transport chain (ETC) hold significant promise to provide valuable insights to the field of mitochondrial research and aging biology. In this study, we investigated two molecules: mycothiazole (MTZ) - from the marine sponge C. mycofijiensis and its more stable semisynthetic analog 8-O-acetylmycothiazole (8-OAc) as potent and selective chemical probes based on their high efficiency to inhibit ETC complex I function. Similar to rotenone (Rote), MTZ, a newly employed ETC complex I inhibitor, exhibited higher cytotoxicity against cancer cell lines compared to certain non-cancer cell lines. Interestingly, 8-OAc demonstrated greater selectivity for cancer cells when compared to both MTZ and Rote, which has promising potential for anticancer therapeutic development. Furthermore, in vivo experiments with these small molecules utilizing a C. elegans model demonstrate their unexplored potential to investigate aging studies. We observed that both molecules have the ability to induce a mitochondria-specific unfolded protein response (UPRMT) pathway, that extends lifespan of worms when applied in their adult stage. We also found that these two molecules employ different pathways to extend lifespan in worms. Whereas MTZ utilizes the transcription factors ATFS-1 and HSF1, which are involved in the UPRMT and heat shock response (HSR) pathways respectively, 8-OAc only required HSF1 and not ATFS-1 to mediate its effects. This observation underscores the value of applying stable, potent, and selective next generation chemical probes to elucidate an important insight into the functional roles of various protein subunits of ETC complexes and their regulatory mechanisms associated with aging.
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ABSTRACT: Prepubertal obesity is growing at an alarming rate and is now considered a risk factor for renal injury. Recently, we reported that the early development of renal injury in obese Dahl salt-sensitive (SS) leptin receptor mutant (SS LepR mutant) rats was associated with increased T-cell infiltration and activation before puberty. Therefore, the current study investigated the effect of inhibiting T-cell activation with abatacept on the progression of renal injury in young obese SS LepR mutant rats before puberty. Four-week-old SS and SS LepR mutant rats were treated with IgG or abatacept (1 mg/kg; ip, every other day) for 4 weeks. Abatacept reduced the renal infiltration of T cells by almost 50% in SS LepR mutant rats. Treatment with abatacept decreased the renal expression of macrophage inflammatory protein-3 alpha while increasing IL-4 in SS LepR mutant rats without affecting SS rats. While not having an impact on blood glucose levels, abatacept reduced hyperinsulinemia and plasma triglycerides in SS LepR mutant rats without affecting SS rats. We did not observe any differences in the mean arterial pressure among the groups. Proteinuria was markedly higher in SS LepR mutant rats than in SS rats throughout the study, and treatment with abatacept decreased proteinuria by about 40% in SS LepR mutant rats without affecting SS rats. We observed significant increases in glomerular and tubular injury and renal fibrosis in SS LepR mutant rats versus SS rats, and chronic treatment with abatacept significantly reduced these renal abnormalities in SS LepR mutant rats. These data suggest that renal T-cell activation contributes to the early progression of renal injury associated with prepubertal obesity.
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Abatacept , Riñón , Obesidad , Ratas Endogámicas Dahl , Receptores de Leptina , Linfocitos T , Animales , Abatacept/farmacología , Obesidad/tratamiento farmacológico , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Riñón/patología , Riñón/efectos de los fármacos , Riñón/metabolismo , Receptores de Leptina/genética , Receptores de Leptina/metabolismo , Receptores de Leptina/deficiencia , Masculino , Ratas , Progresión de la Enfermedad , Modelos Animales de Enfermedad , Proteinuria/tratamiento farmacológico , Enfermedades Renales/patología , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/metabolismo , Maduración Sexual/efectos de los fármacosRESUMEN
Redox conditions in groundwater may markedly affect the fate and transport of nutrients, volatile organic compounds, and trace metals, with significant implications for human health. While many local assessments of redox conditions have been made, the spatial variability of redox reaction rates makes the determination of redox conditions at regional or national scales problematic. In this study, redox conditions in groundwater were predicted for the contiguous United States using random forest classification by relating measured water quality data from over 30,000 wells to natural and anthropogenic factors. The model correctly predicted the oxic/suboxic classification for 78 and 79% of the samples in the out-of-bag and hold-out data sets, respectively. Variables describing geology, hydrology, soil properties, and hydrologic position were among the most important factors affecting the likelihood of oxic conditions in groundwater. Important model variables tended to relate to aquifer recharge, groundwater travel time, or prevalence of electron donors, which are key drivers of redox conditions in groundwater. Partial dependence plots suggested that the likelihood of oxic conditions in groundwater decreased sharply as streams were approached and gradually as the depth below the water table increased. The probability of oxic groundwater increased as base flow index values increased, likely due to the prevalence of well-drained soils and geologic materials in high base flow index areas. The likelihood of oxic conditions increased as topographic wetness index (TWI) values decreased. High topographic wetness index values occur in areas with a propensity for standing water and overland flow, conditions that limit the delivery of dissolved oxygen to groundwater by recharge; higher TWI values also tend to occur in discharge areas, which may contain groundwater with long travel times. A second model was developed to predict the probability of elevated manganese (Mn) concentrations in groundwater (i.e., ≥50 µg/L). The Mn model relied on many of the same variables as the oxic/suboxic model and may be used to identify areas where Mn-reducing conditions occur and where there is an increased risk to domestic water supplies due to high Mn concentrations. Model predictions of redox conditions in groundwater produced in this study may help identify regions of the country with elevated groundwater vulnerability and stream vulnerability to groundwater-derived contaminants.
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Agua Subterránea , Contaminantes Químicos del Agua , Humanos , Bosques Aleatorios , Monitoreo del Ambiente , Abastecimiento de Agua , Suelo , Manganeso , Oxidación-Reducción , Contaminantes Químicos del Agua/análisisRESUMEN
In this 2-institution feasibility pilot, oncology fellows used and updated freely available web-based learning tools (scaffolds) in a constructivist fashion.
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BACKGROUND AND OBJECTIVES: Patient and Family Centered I-PASS (PFC I-PASS) emphasizes family and nurse engagement, health literacy, and structured communication on family-centered rounds organized around the I-PASS framework (Illness severity-Patient summary-Action items-Situational awareness-Synthesis by receiver). We assessed adherence, safety, and experience after implementing PFC I-PASS using a novel "Mentor-Trio" implementation approach with multidisciplinary parent-nurse-physician teams coaching sites. METHODS: Hybrid Type II effectiveness-implementation study from 2/29/19-3/13/22 with ≥3 months of baseline and 12 months of postimplementation data collection/site across 21 US community and tertiary pediatric teaching hospitals. We conducted rounds observations and surveyed nurses, physicians, and Arabic/Chinese/English/Spanish-speaking patients/parents. RESULTS: We conducted 4557 rounds observations and received 2285 patient/family, 1240 resident, 819 nurse, and 378 attending surveys. Adherence to all I-PASS components, bedside rounding, written rounds summaries, family and nurse engagement, and plain language improved post-implementation (13.0%-60.8% absolute increase by item), all P < .05. Except for written summary, improvements sustained 12 months post-implementation. Resident-reported harms/1000-resident-days were unchanged overall but decreased in larger hospitals (116.9 to 86.3 to 72.3 pre versus early- versus late-implementation, P = .006), hospitals with greater nurse engagement on rounds (110.6 to 73.3 to 65.3, P < .001), and greater adherence to I-PASS structure (95.3 to 73.6 to 72.3, P < .05). Twelve of 12 measures of staff safety climate improved (eg, "excellent"/"very good" safety grade improved from 80.4% to 86.3% to 88.0%), all P < .05. Patient/family experience and teaching were unchanged. CONCLUSIONS: Hospitals successfully used Mentor-Trios to implement PFC I-PASS. Family/nurse engagement, safety climate, and harms improved in larger hospitals and hospitals with better nurse engagement and intervention adherence. Patient/family experience and teaching were not affected.
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Mentores , Rondas de Enseñanza , Humanos , Niño , Padres , Hospitales de Enseñanza , Comunicación , LenguajeRESUMEN
BACKGROUND: Pathological fractures have been reported in equids with pituitary pars intermedia dysfunction (PPID) but their prevalence and pathogenesis is unknown. OBJECTIVES: To compare: (1) bone mineral density (BMD) in weight bearing and nonweight bearing bones in PPID+ equids and aged and young PPID- controls; and (2) biomechanical properties of the fourth lumbar vertebral body in PPID+ equids and aged PPID- equids. STUDY DESIGN: Case-control study: five PPID+ equids and six aged and four young PPID- control horses. METHODS: PPID status was based on clinical signs and necropsy examination of the pituitary gland (PG). The lumbar vertebral column, right front third metacarpus (MC3), left hind third metatarsus (MT3), and PG were removed after euthanasia. BMD was determined by quantitative computed tomography of regions of interest (ROI) in each bone and biomechanical testing was performed on the fourth lumbar vertebral body. Serum concentrations of parathormone (PTH), ionised Ca++ , 25-hydroxyvitamin D, and osteocalcin (OC) were also measured. Data were analysed using one-way ANOVA and correlation analyses. RESULTS: BMD of trabecular and cortical regions of interest (ROI) of the third, fourth (L4), and fifth lumbar vertebrae were significantly lower in PPID+ equids as compared with aged (p < 0. 001) and young (p < 0.01) PPID- controls. In contrast, no differences were found in BMD of trabecular or cortical ROIs of MC3 and MT3 between groups. No differences were detected in force at fracture, displacement at fracture, Young's modulus or strain of L4 between PPID+ and aged PPID- horses. No differences were found in serum PTH, ionised Ca++ , 25-hydroxyvitamin D, or OC concentrations between groups. MAIN LIMITATIONS: Limited number of equids studied and variation in test results. CONCLUSIONS: BMD of nonweight bearing bones can be decreased with PPID and could increase risk of developing pathological fractures.
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Fracturas Espontáneas , Enfermedades de los Caballos , Enfermedades de la Hipófisis , Adenohipófisis Porción Intermedia , Caballos , Animales , Vértebras Lumbares/patología , Estudios de Casos y Controles , Densidad Ósea , Fracturas Espontáneas/patología , Fracturas Espontáneas/veterinaria , Adenohipófisis Porción Intermedia/patología , Enfermedades de la Hipófisis/veterinaria , Enfermedades de la Hipófisis/diagnóstico , Enfermedades de los Caballos/diagnósticoRESUMEN
Small molecule inhibitors of the mitochondrial electron transport chain (ETC) hold significant promise to provide valuable insights to the field of mitochondrial research and aging biology. In this study, we investigated two molecules: mycothiazole (MTZ) - from the marine sponge C. mycofijiensis and its more stable semisynthetic analog 8-O-acetylmycothiazole (8-OAc) as potent and selective chemical probes based on their high efficiency to inhibit ETC complex I function. Similar to rotenone (Rote), a widely used ETC complex I inhibitor, these two molecules showed cytotoxicity to cancer cells but strikingly demonstrate a lack of toxicity to non-cancer cells, a highly beneficial feature in the development of anti-cancer therapeutics. Furthermore, in vivo experiments with these small molecules utilizing C.elegans model demonstrate their unexplored potential to investigate aging studies. We observed that both molecules have the ability to induce a mitochondria-specific unfolded protein response (UPRMT) pathway, that extends lifespan of worms when applied in their adult stage. Interestingly, we also found that these two molecules employ different pathways to extend lifespan in worms. Whereas MTZ utilize the transcription factors ATFS-1 and HSF-1, which are involved in the UPRMT and heat shock response (HSR) pathways respectively, 8-OAc only required HSF-1 and not ATFS-1 to mediate its effects. This observation underscores the value of applying stable, potent, and selective next generation chemical probes to elucidate an important insight into the functional roles of various protein subunits of ETC complexes and their regulatory mechanisms associated with aging.
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Atmospheric plasma processing, which combines the efficacy of chemical processes and the safety of physical processes, has been used to modify the surface characteristics of graphite-based materials. In this work, two distinct plasma source gases, C4F8 and O2, with the addition of a rotary reactor were used. The effectiveness of modifying the basal plane of intercalated graphite nanoplatelets (GnP) was investigated with various analytical techniques and the visual observation of the dispersion of these plasma-treated GnP in solvents was also reported. It is shown that this low-temperature plasma processing technique can be used to successfully modify the GnP surface without significantly changing the intrinsic structure of the GnP, which is desirable in many applications. With the C4F8 plasma treatment, the immersion characteristics in solvents can be tuned and the functional groups present on the surface can be tailored to produce desired bonding environments. This surface chemistry tunability will provide the needed functionalities in creating graphene-containing composite materials.
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Lysosomal storage disorders (LSDs) are a genetically and clinically diverse group of diseases characterized by lysosomal dysfunction. Batten disease is a family of severe LSDs primarily impacting the central nervous system. Here we show that AF38469, a small molecule inhibitor of sortilin, improves lysosomal and glial pathology across multiple LSD models. Live-cell imaging and comparative transcriptomics demonstrates that the transcription factor EB (TFEB), an upstream regulator of lysosomal biogenesis, is activated upon treatment with AF38469. Utilizing CLN2 and CLN3 Batten disease mouse models, we performed a short-term efficacy study and show that treatment with AF38469 prevents the accumulation of lysosomal storage material and the development of neuroinflammation, key disease associated pathologies. Tremor phenotypes, an early behavioral phenotype in the CLN2 disease model, were also completely rescued. These findings reveal sortilin inhibition as a novel and highly efficacious therapeutic modality for the treatment of multiple forms of Batten disease.
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OBJECTIVE: Identify the prevalence of food insecurity (FI) and compare sociodemographic, mental, physical, behavioral, and environmental risk factors for FI among students at a private university, community college, and historically black college or university (HBCU). PARTICIPANTS: Adult students attending a private university, community college, or HBCU (n = 4,140) located within the southeastern United States. METHODS: Using an online survey (2017-2019), FI, sociodemographic, mental, physical, behavioral, and environmental data were collected to understand their association with FI. RESULTS: Up to 37.1% of students experienced FI. Identifying as black, other/multi-racial, having poor sleep, federal loans, depressive symptoms, high stress, social isolation, or a chronic condition were associated with FI. These associations varied by institution. CONCLUSIONS: FI is prevalent within diverse post-secondary institutions that serve traditional and nontraditional students with risk factors varying between institutions. The prevalence of FI and risk factors can inform institutional policy responses to ameliorate the effects of FI.
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With antimicrobial resistance (AMR) remaining a persistent and growing threat to human health worldwide, membrane-active peptides are gaining traction as an alternative strategy to overcome the issue. Membrane-embedded multi-drug resistant (MDR) efflux pumps are a prime target for membrane-active peptides, as they are a well-established contributor to clinically relevant AMR infections. Here, we describe a series of transmembrane peptides (TMs) to target the oligomerization motif of the AcrB component of the AcrAB-TolC MDR efflux pump from Escherichia coli. These peptides contain an N-terminal acetyl-A-(Sar)3 (sarcosine; N-methylglycine) tag and a C-terminal lysine tag-a design strategy our lab has utilized to improve the solubility and specificity of targeting for TMs previously. While these peptides have proven useful in preventing AcrB-mediated substrate efflux, the mechanisms by which these peptides associate with and penetrate the bacterial membrane remained unknown. In this study, we have shown peptide hydrophobic moment (µH)-the measure of concentrated hydrophobicity on one face of a lipopathic α-helix-drives bacterial membrane permeabilization and depolarization, likely through lateral-phase separation of negatively-charged POPG lipids and the disruption of lipid packing. Our results show peptide µH is an important consideration when designing membrane-active peptides and may be the determining factor in whether a TM will function in a permeabilizing or non-permeabilizing manner when embedded in the bacterial membrane.
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Proteínas de Escherichia coli , Humanos , Proteínas de Escherichia coli/metabolismo , Antibacterianos/química , Escherichia coli/metabolismo , Péptidos , Interacciones Hidrofóbicas e Hidrofílicas , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/químicaRESUMEN
During nervous system development, neurons choose synaptic partners with remarkable specificity; however, the cell-cell recognition mechanisms governing rejection of inappropriate partners remain enigmatic. Here, we show that mouse retinal neurons avoid inappropriate partners by using the FLRT2-uncoordinated-5 (UNC5) receptor-ligand system. Within the inner plexiform layer (IPL), FLRT2 is expressed by direction-selective (DS) circuit neurons, whereas UNC5C/D are expressed by non-DS neurons projecting to adjacent IPL sublayers. In vivo gain- and loss-of-function experiments demonstrate that FLRT2-UNC5 binding eliminates growing DS dendrites that have strayed from the DS circuit IPL sublayers. Abrogation of FLRT2-UNC5 binding allows mistargeted arbors to persist, elaborate, and acquire synapses from inappropriate partners. Conversely, UNC5C misexpression within DS circuit sublayers inhibits dendrite growth and drives arbors into adjacent sublayers. Mechanistically, UNC5s promote dendrite elimination by interfering with FLRT2-mediated adhesion. Based on their broad expression, FLRT-UNC5 recognition is poised to exert widespread effects upon synaptic partner choices across the nervous system.
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Neuronas , Retina , Animales , Ratones , Neuronas/fisiología , Transducción de Señal , Comunicación Celular , Sinapsis/fisiología , Dendritas/fisiología , Glicoproteínas de Membrana/metabolismoRESUMEN
This article summarizes the definitions of vigilance, fatigue, and sleepiness, as well as tools used in their assessment. Consideration is given to the strengths and limitations of the different subjective and objective tools. Future directions for research are also discussed, as well as the public health importance of continued investigation in this subject.
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Trastornos de Somnolencia Excesiva , Vigilia , Humanos , FatigaRESUMEN
Prepubertal obesity is currently an epidemic and is considered as a major risk factor for renal injury. Previous studies have demonstrated that insulin resistance contributes to renal injury in obesity, independent of diabetes. However, studies examining the relationship between insulin resistance and renal injury in obese children are lacking. Recently, we reported that progressive renal injury in Dahl salt-sensitive (SS) leptin receptor mutant (SSLepRmutant) rats was associated with insulin resistance before puberty. Therefore, the aim of the present study was to examine whether decreasing insulin resistance with metformin will reduce renal injury in SSLepRmutant rats. Four-wk-old SS and SSLepRmutant rats were separated into the following two groups: 1) vehicle and 2) metformin (300 mg/kg/day) via chow diet for 4 wk. Chronic administration of metformin markedly reduced insulin resistance and dyslipidemia in SSLepRmutant rats. We did not detect any differences in mean arterial pressure between vehicle and metformin-treated SS and SSLepRmutant rats. Proteinuria was significantly greater in SSLepRmutant rats versus SS rats throughout the study, and metformin administration significantly reduced proteinuria in SSLepRmutant rats. At the end of the protocol, metformin prevented the renal hyperfiltration observed in SSLepRmutant rats versus SS rats. Glomerular and tubular injury and renal inflammation and fibrosis were significantly higher in vehicle-treated SSLepRmutant rats versus SS rats, and metformin reduced these parameters in SSLepRmutant rats. These data suggest that reducing insulin resistance with metformin prevents renal hyperfiltration and progressive renal injury in SSLepRmutant rats before puberty and may be therapeutically useful in managing renal injury during prepubertal obesity.NEW & NOTEWORTHY Childhood/prepubertal obesity is a public health concern that is associated with early signs of proteinuria. Insulin resistance has been described in obese children. However, studies investigating the role of insulin resistance during childhood obesity-associated renal injury are limited. This study provides evidence of an early relationship between insulin resistance and renal injury in a rat model of prepubertal obesity. These data also suggest that reducing insulin resistance with metformin may be renoprotective in obese children.
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Hipertensión , Resistencia a la Insulina , Metformina , Obesidad Infantil , Ratas , Animales , Ratas Endogámicas Dahl , Metformina/farmacología , Obesidad Infantil/complicaciones , Riñón , Proteinuria/prevención & control , Cloruro de Sodio Dietético , Hipertensión/tratamiento farmacológico , Hipertensión/etiología , Presión SanguíneaRESUMEN
Mouse models of CLN3 Batten disease, a rare lysosomal storage disorder with no cure, have improved our understanding of CLN3 biology and therapeutics through their ease of use and a consistent display of cellular pathology. However, the translatability of murine models is limited by disparities in anatomy, body size, life span and inconsistent subtle behavior deficits that can be difficult to detect in CLN3 mutant mouse models, thereby limiting their use in preclinical studies. Here, we present a longitudinal characterization of a novel miniswine model of CLN3 disease that recapitulates the most common human pathogenic variant, an exon 7-8 deletion (CLN3Δex7/8). Progressive pathology and neuron loss is observed in various regions of the CLN3Δex7/8 miniswine brain and retina. Additionally, mutant miniswine present with retinal degeneration and motor abnormalities, similar to deficits seen in humans diagnosed with the disease. Taken together, the CLN3Δex7/8 miniswine model shows consistent and progressive Batten disease pathology, and behavioral impairment mirroring clinical presentation, demonstrating its value in studying the role of CLN3 and safety/efficacy of novel disease-modifying therapeutics.