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1.
Mol Psychiatry ; 29(8): 2399-2407, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38491344

RESUMEN

Persons diagnosed with schizophrenia (SCZ) or bipolar I disorder (BPI) are at high risk for self-injurious behavior, suicidal ideation, and suicidal behaviors (SB). Characterizing associations between diagnosed health problems, prior pharmacological treatments, and polygenic scores (PGS) has potential to inform risk stratification. We examined self-reported SB and ideation using the Columbia Suicide Severity Rating Scale (C-SSRS) among 3,942 SCZ and 5,414 BPI patients receiving care within the Veterans Health Administration (VHA). These cross-sectional data were integrated with electronic health records (EHRs), and compared across lifetime diagnoses, treatment histories, follow-up screenings, and mortality data. PGS were constructed using available genomic data for related traits. Genome-wide association studies were performed to identify and prioritize specific loci. Only 20% of the veterans who reported SB had a corroborating ICD-9/10 EHR code. Among those without prior SB, more than 20% reported new-onset SB at follow-up. SB were associated with a range of additional clinical diagnoses, and with treatment with specific classes of psychotropic medications (e.g., antidepressants, antipsychotics, etc.). PGS for externalizing behaviors, smoking initiation, suicide attempt, and major depressive disorder were associated with SB. The GWAS for SB yielded no significant loci. Among individuals with a diagnosed mental illness, self-reported SB were strongly associated with clinical variables across several EHR domains. Analyses point to sequelae of substance-related and psychiatric comorbidities as strong correlates of prior and subsequent SB. Nonetheless, past SB was frequently not documented in health records, underscoring the value of regular screening with direct, in-person assessments, especially among high-risk individuals.


Asunto(s)
Trastorno Bipolar , Estudio de Asociación del Genoma Completo , Esquizofrenia , Ideación Suicida , Veteranos , Humanos , Trastorno Bipolar/genética , Trastorno Bipolar/epidemiología , Esquizofrenia/genética , Esquizofrenia/epidemiología , Masculino , Femenino , Veteranos/psicología , Estados Unidos/epidemiología , Persona de Mediana Edad , Adulto , Estudio de Asociación del Genoma Completo/métodos , Estudios Transversales , Factores de Riesgo , Intento de Suicidio , Conducta Autodestructiva/genética , Conducta Autodestructiva/epidemiología , Suicidio/estadística & datos numéricos , Suicidio/psicología , Predisposición Genética a la Enfermedad/genética , Anciano , Registros Electrónicos de Salud , Herencia Multifactorial/genética
2.
Biotechnol Bioeng ; 121(2): 784-794, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37926950

RESUMEN

Efficient co-utilization of mixed sugar feedstocks remains a biomanufacturing challenge, thus motivating ongoing efforts to engineer microbes for improved conversion of glucose-xylose mixtures. This study focuses on enhancing phenylalanine production by engineering Escherichia coli to efficiently co-utilize glucose and xylose. Flux balance analysis identified E4P flux as a bottleneck which could be alleviated by increasing the xylose-to-glucose flux ratio. A mutant copy of the xylose-specific activator (XylR) was then introduced into the phenylalanine-overproducing E. coli NST74, which relieved carbon catabolite repression and enabled efficient glucose-xylose co-utilization. Carbon contribution analysis through 13 C-fingerprinting showed a higher preference for xylose in the engineered strain (NST74X), suggesting superior catabolism of xylose relative to glucose. As a result, NST74X produced 1.76 g/L phenylalanine from a model glucose-xylose mixture; a threefold increase over NST74. Then, using biomass-derived sugars, NST74X produced 1.2 g/L phenylalanine, representing a 1.9-fold increase over NST74. Notably, and consistent with the carbon contribution analysis, the xylR* mutation resulted in a fourfold greater maximum rate of xylose consumption without significantly impeding the maximum rate of total sugar consumption (0.87 vs. 0.70 g/L-h). This study presents a novel strategy for enhancing phenylalanine production through the co-utilization of glucose and xylose in aerobic E. coli cultures, and highlights the potential synergistic benefits associated with using substrate mixtures over single substrates when targeting specific products.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Azúcares/metabolismo , Xilosa/metabolismo , Biomasa , Fermentación , Glucosa/metabolismo , Aminoácidos Aromáticos/metabolismo , Fenilalanina/metabolismo , Carbono/metabolismo , Factores de Transcripción/genética , Proteínas de Escherichia coli/metabolismo
3.
Nicotine Tob Res ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028574

RESUMEN

INTRODUCTION: Cigarette use and smoking intensity increase risk of suicidal ideation. Less is known about e-cigarette use. Here we examine direct influences of cigarette versus e-cigarette use on suicidal ideation among 16-to-23-year-olds in Texas. METHODS: Since 2019 the Texas Adolescent Tobacco and Marketing Surveillance study collected data on suicidal ideation every six months covering the previous two-weeks. Youths answering that they had "thoughts that you would be better off dead, or of hurting yourself" on more than two of 14 days were categorized as having suicidal ideation. Generalized linear mixed-effects logistic regressions examined the influence of ever and past 30-day (P30D) use of cigarettes, e-cigarettes, impulsivity and anxiety on suicidal ideation, controlling for gender, race/ethnicity, SES, and grade in school. Interactions between ever and P30D use of both products and a) impulsivity and b) gender were examined. RESULTS: Of the 2,329 participants, 29.1% reported ever and 6.5% reported P30D cigarette use, 48.2% reported ever and 11.6% reported P30D e-cigarette use, and 18.5% reported suicidal ideation. Ever cigarette use among females (aOR=1.83; 95% CI: 1.36-2.46), P30D e-cigarette use (aOR=1.30; 95% CI: 1.00-1.68), and P30D cigarette use (aOR=1.47; 95% CI: 1.06-2.05) were independently associated with higher risk for suicidal ideation, after adjusting for covariates. Impulsivity and anxiety directly increased risk for suicidal ideation regardless of product type used. Hispanic youth had higher risk of suicidal ideation than white youth, while higher levels of SES were protective. CONCLUSION: Cigarette/e-cigarette use, as well as impulsivity and anxiety, directly increase the risk of suicidal ideation. IMPLICATIONS: Clinicians should ask young adults with a history of tobacco use, anxiety or impulsive behavior, about suicidal ideationNicotine prevention and cessation programs might be more effective if they simultaneously target substance use and mental healthCulturally appropriate support is needed for ethnic and racial minority youth and young adults in school, college and at workWhen evaluating and understanding risk, the role of multiple social identities (such as minority status, gender, and SES) is important.

4.
Bioprocess Biosyst Eng ; 47(2): 223-233, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38142425

RESUMEN

Anaerobic succinate fermentations can achieve high-titer, high-yield performance while fixing CO2 through the reductive branch of the tricarboxylic acid cycle. To provide the needed CO2, conventional media is supplemented with significant (up to 60 g/L) bicarbonate (HCO3-), and/or carbonate (CO32-) salts. However, producing these salts from CO2 and natural ores is thermodynamically unfavorable and, thus, energetically costly, which reduces the overall sustainability of the process. Here, a series of composite hollow fiber membranes (HFMs) were first fabricated, after which comprehensive CO2 mass transfer measurements were performed under cell-free conditions using a novel, constant-pH method. Lumen pressure and total HFM surface area were found to be linearly correlated with the flux and volumetric rate of CO2 delivery, respectively. Novel HFM bioreactors were then constructed and used to comprehensively investigate the effects of modulating the CO2 delivery rate on succinate fermentations by engineered Escherichia coli. Through appropriate tuning of the design and operating conditions, it was ultimately possible to produce up to 64.5 g/L succinate at a glucose yield of 0.68 g/g; performance approaching that of control fermentations with directly added HCO3-/CO32- salts and on par with prior studies. HFMs were further found to demonstrate a high potential for repeated reuse. Overall, HFM-based CO2 delivery represents a viable alternative to the addition of HCO3-/CO32- salts to succinate fermentations, and likely other 'dark' CO2-fixing fermentations.


Asunto(s)
Dióxido de Carbono , Ácido Succínico , Fermentación , Dióxido de Carbono/farmacología , Sales (Química) , Succinatos , Escherichia coli , Carbonatos/farmacología
5.
Sensors (Basel) ; 24(16)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39204992

RESUMEN

In this paper, the problem of estimating a scalar field (e.g., the spatial distribution of contaminants in an area) using a sensor network is considered. The sensors are assumed to have quantized measurements. We consider distributed estimation algorithms where each sensor forms its own estimate of the field, with sensors able to share information locally with its neighbours. Two schemes are proposed, called, respectively, measurement diffusion and estimate diffusion. In the measurement diffusion scheme, each sensor broadcasts to its neighbours the latest received measurements of every sensor in the network, while in the estimate diffusion scheme, each sensor will broadcast local estimates and Hessians to its neighbours. Information received from its neighbours will then be iteratively combined at each sensor to form the field estimates. Time-varying scalar fields can also be estimated using both the measurement diffusion and estimate diffusion schemes. Numerical studies illustrate the performance of the proposed algorithms, in particular demonstrating steady state performance close to that of centralized estimation.

6.
Am J Addict ; 32(5): 506-509, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37337750

RESUMEN

BACKGROUND AND OBJECTIVES: This study examined how a promoter variant of TH (rs10770141) affects subjective effects of cocaine in 65 nontreatment-seeking individuals with cocaine dependence. METHODS: Participants received cocaine/saline intravenously, and TH genotypes were evaluated. RESULTS: Homozygous individuals for the minor T allele reported greater "good" and "bad" subjective effects to cocaine than those with the major C allele. DISCUSSION AND CONCLUSIONS: TH rs10770141 modulates subjective effects of cocaine in participants with cocaine dependence. SCIENTIFIC SIGNIFICANCE: These results are among the first to indicate that homozygosity of the T allele of rs10770141 modulates greater sensitivity to cocaine.


Asunto(s)
Trastornos Relacionados con Cocaína , Cocaína , Humanos , Cocaína/farmacología , Trastornos Relacionados con Cocaína/genética , Genotipo , Alelos , Regiones Promotoras Genéticas
7.
Eur Spine J ; 32(6): 1911-1926, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37071155

RESUMEN

PURPOSE: The rate of elective lumbar fusion has continued to increase over the past two decades. However, there remains to be a consensus on the optimal fusion technique. This study aims to compare stand-alone anterior lumbar interbody fusion (ALIF) with posterior fusion techniques in patients with spondylolisthesis and degenerative disc disease through a systematic review and meta-analysis of the available literature. METHODS: A systematic review was performed by searching the Cochrane Register of Trials, MEDLINE, and EMBASE from inception to 2022. In the two-stage screening process, three reviewers independently reviewed titles and abstracts. The full-text reports of the remaining studies were then inspected for eligibility. Conflicts were resolved through consensus discussion. Two reviewers then extracted study data, assessed it for quality, and analysed it. RESULTS: After the initial search and removal of duplicate records, 16,435 studies were screened. Twenty-one eligible studies (3686 patients) were ultimately included, which compared stand-alone ALIF with posterior approaches such as posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), and posterolateral lumbar fusion (PLF). A meta-analysis showed surgical time and blood loss was significantly lower in ALIF than in TLIF/PLIF, but not in those who underwent PLF (p = 0.08). The length of hospital stay was significantly shorter in ALIF than in TLIF, but not in PLIF or PLF. Fusion rates were similar between the ALIF and posterior approaches. The Visual Analogue Scale (VAS) scores for back and leg pain were not significantly different between the ALIF and PLIF/TLIF groups. However, VAS back pain favoured ALIF over PLF at one year (n = 21, MD - 1.00, CI - 1.47, - 0.53), and at two years (2 studies, n = 67, MD - 1.39, CI - 1.67, - 1.11). The VAS leg pain scores (n = 46, MD 0.50, CI 0.12 to 0.88) at two years significantly favoured PLF. The Oswestry Disability Index (ODI) scores at one year were not significantly different between ALIF and the posterior approaches. At two years, ODI scores were also similar between the ALIF and the TLIF/PLIF. However, the ODI scores at two years (2 studies, n = 67, MD - 7.59, CI - 13.33, - 1.85) significantly favoured ALIF over PLF (I2 = 70%). The Japanese Orthopaedic Association Score (JOAS) for low back pain at one year (n = 21, MD - 0.50, CI - 0.78) and two years (two studies, n = 67, MD - 0.36, CI - 0.65, - 0.07) significantly favoured ALIF over PLF. No significant differences were found in leg pain at the 2-year follow-up. Adverse events displayed no significant differences between the ALIF and posterior approaches. CONCLUSIONS: Stand-alone-ALIF demonstrated a shorter operative time and less blood loss than the PLIF/TLIF approach. Hospitalisation time is reduced with ALIF compared with TLIF. Patient-reported outcome measures were equivocal with PLIF or TLIF. VAS and JOAS, back pain, and ODI scores mainly favoured ALIF over PLF. Adverse events were equivocal between the ALIF and posterior fusion approaches.


Asunto(s)
Dolor de la Región Lumbar , Fusión Vertebral , Espondilolistesis , Humanos , Fusión Vertebral/efectos adversos , Fusión Vertebral/métodos , Vértebras Lumbares/cirugía , Dolor de Espalda/etiología , Región Lumbosacra/cirugía , Dolor de la Región Lumbar/etiología , Espondilolistesis/cirugía , Resultado del Tratamiento , Estudios Retrospectivos
8.
Metab Eng ; 72: 133-149, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35289291

RESUMEN

Robust systematic approaches for the metabolic engineering of cell factories remain elusive. The available models for predicting phenotypical responses and mechanisms are incomplete, particularly within the context of compound toxicity that can be a significant impediment to achieving high yields of a target product. This study describes a Multi-Omic Based Production Strain Improvement (MOBpsi) strategy that is distinguished by integrated time-resolved systems analyses of fed-batch fermentations. As a case study, MOBpsi was applied to improve the performance of an Escherichia coli cell factory producing the commodity chemical styrene. Styrene can be bio-manufactured from phenylalanine via an engineered pathway comprised of the enzymes phenylalanine ammonia lyase and ferulic acid decarboxylase. The toxicity, hydrophobicity, and volatility of styrene combine to make bio-production challenging. Previous attempts to create styrene tolerant E. coli strains by targeted genetic interventions have met with modest success. Application of MOBpsi identified new potential targets for improving performance, resulting in two host strains (E. coli NST74ΔaaeA and NST74ΔaaeA cpxPo) with increased styrene production. The best performing re-engineered chassis, NST74ΔaaeA cpxPo, produced ∼3 × more styrene and exhibited increased viability in fed-batch fermentations. Thus, this case study demonstrates the utility of MOBpsi as a systematic tool for improving the bio-manufacturing of toxic chemicals.


Asunto(s)
Escherichia coli , Ingeniería Metabólica , Escherichia coli/metabolismo , Fermentación , Ingeniería Metabólica/métodos , Fenilalanina/genética , Fenilalanina/metabolismo , Estireno/metabolismo
9.
Alcohol Clin Exp Res ; 46(12): 2191-2202, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36281832

RESUMEN

BACKGROUND: Endophenotypes for alcohol use disorder are well known and may reflect paternal exposure effects passed down to offspring via epigenetic mechanisms. Previously, we showed that paternal alcohol exposure prior to conception attenuates the acquisition of operant alcohol self-administration. We now test whether paternal alcohol exposure alters their offsprings' behavioral responses to alcohol (endophenotypes) and global DNA methylation levels in reward-related brain regions. METHODS: Adult male rats were exposed to alcohol vapors or air for 6 weeks and mated with alcohol-naïve females 8 weeks later. Adult male and female offspring of the alcohol- and control-sired litters were tested on three behaviors 30 m after gavage with water or alcohol (1.5 g/kg): open field, elevated plus maze, and accelerating rotarod. Global DNA methylation levels in sperm, nucleus accumbens, and prefrontal cortex were examined in male sires and in another group of offspring. RESULTS: Alcohol-sired males showed less anxiety-like behavior in the elevated plus maze that was not affected by alcohol administration. By contrast, alcohol had anxiolytic effects in the open field in male offspring only with no paternal alcohol effect. Neither paternal alcohol exposure nor alcohol administration altered locomotor activity in either sex. Sex-specific effects of paternal alcohol exposure were seen in the rotarod test. Alcohol-sired male offspring showed blunted sensitivity to the alcohol's motor-impairing effects, whereas alcohol-sired female offspring showed enhanced sensitivity. Global DNA methylation was altered in the sperm of alcohol-exposed males, but no changes were seen in their offspring. CONCLUSIONS: Paternal alcohol exposure prior to conception has sex- and task-dependent effects on unconditioned behaviors in their offspring.


Asunto(s)
Exposición Paterna , Semen , Humanos , Masculino , Animales , Ratas , Femenino , Exposición Paterna/efectos adversos , Etanol , Ansiedad/genética , Consumo de Bebidas Alcohólicas
10.
Eur J Clin Pharmacol ; 78(6): 965-973, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35218405

RESUMEN

PURPOSE: The aim of this secondary analysis was to identify prodynorphin (PDYN) genetic markers moderating the therapeutic response to treatment of cocaine dependence with buprenorphine/naloxone (Suboxone®; BUP). METHODS: Cocaine-dependent participants (N = 302) were randomly assigned to a platform of injectable, extended-release naltrexone (XR-NTX) and one of three daily medication arms: 4 mg BUP (BUP4), 16 mg BUP (BUP16), or placebo (PLB) for 8 weeks (Parent Trial Registration: Protocol ID: NIDA-CTN-0048, Clinical Trials.gov ID: NCT01402492). DNA was obtained from 277 participants. Treatment response was determined from weeks 3 to 7 over each 1-week period by the number of cocaine-positive urines per total possible urines. RESULTS: In the cross-ancestry group, the PLB group had more cocaine-positive urines than the BUP16 group (P = 0.0021). The interactions of genetic variant × treatment were observed in the rs1022563 A-allele carrier group where the BUP16 group (N = 35) had fewer cocaine-positive urines (P = 0.0006) than did the PLB group (N = 26) and in the rs1997794 A-allele carrier group where the BUP16 group (N = 49) had fewer cocaine-positive urines (P = 0.0003) than did the PLB group (N = 58). No difference was observed in the rs1022563 GG or rs1997794 GG genotype groups between the BUP16 and PLB groups. In the African American-ancestry subgroup, only the rs1022563 A-allele carrier group was associated with treatment response. CONCLUSION: These results suggest that PDYN variants may identify patients who are best suited to treatment with XR-NTX plus buprenorphine for cocaine use disorder pharmacotherapy.


Asunto(s)
Buprenorfina , Trastornos Relacionados con Cocaína , Cocaína , Trastornos Relacionados con Opioides , Buprenorfina/uso terapéutico , Combinación Buprenorfina y Naloxona/uso terapéutico , Cocaína/uso terapéutico , Trastornos Relacionados con Cocaína/tratamiento farmacológico , Trastornos Relacionados con Cocaína/genética , Preparaciones de Acción Retardada/uso terapéutico , Encefalinas , Humanos , Inyecciones Intramusculares , Naltrexona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Precursores de Proteínas
11.
Addict Biol ; 27(1): e13078, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34363290

RESUMEN

Familial transmission of alcohol use disorder reflects genetic and environmental factors. Paternal alcohol exposure may affect rodent offspring via epigenetic modifications transmitted through the male germ line. While such exposure alters alcohol sensitivity in mouse offspring, no studies examined if it impacts the development of operant alcohol self-administration in rats. We exposed male (sires) Wistar rats to chronic intermittent ethanol in vapour chambers (16 h/day; 5 days/week) or to air for 6 weeks. Eight weeks later, rats were mated with alcohol-naive females. Adult alcohol- and control-sired F1 offspring were assessed in acquisition of alcohol self-administration in which increasing alcohol concentrations (2.5%, 5% and 10%, v/v) were delivered after one lever press (fixed ratio 1 or FR1). Prior to alcohol sessions, rats were trained to lever press for food delivery under an FR1 schedule of reinforcement. DNA methylation levels of the brain derived neurotrophic factor (Bdnf) gene were measured in sperm, nucleus accumbens (NAc) and medial prefrontal cortex (mPFC) in sires and in offspring. Alcohol-exposed sires had lower Bdnf DNA methylation levels in NAc and greater methylation levels in mPFC. Although this pattern was not recapitulated in offspring, alcohol-sired offspring of both sexes did show aberrant Bdnf DNA methylation patterns compared to control-sired offspring. Alcohol-sired offspring self-administered less alcohol (5% and 10%) with no group differences in food responding. Results indicate that paternal alcohol exposure prior to conception protects against alcohol's initial reinforcing effects but the pattern of dysregulated Bdnf methylation in reward-related circuitry did not mimic changes seen in sires.


Asunto(s)
Alcoholismo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Metilación de ADN , Etanol/farmacología , Animales , Condicionamiento Operante/efectos de los fármacos , Epigénesis Genética , Femenino , Masculino , Núcleo Accumbens/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Ratas , Ratas Wistar , Refuerzo en Psicología , Autoadministración
12.
Foot Ankle Surg ; 28(1): 20-24, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33500217

RESUMEN

BACKGROUND: The use of smartphones and multimedia messaging service (MMS) continues to increase in day to day orthopaedic clinical practice. However, there is limited evidence to support the safe utilisation of MMS. OBJECTIVES: The aim of this study was to correlate the performance of MMS imaging to picture archiving and communication systems (PACS) imaging within the setting of diagnosis and management of ankle fractures. METHODS: The ankle fracture radiograph series of 82 consecutive patients were evaluated by five orthopaedic consultant specialists. A questionnaire regarding diagnosis and preferred management was completed separately for each patient using smartphone and PACS images. Statistical analysis was performed using Intraclass Correlation Coefficient (ICC). RESULTS: Ankle fracture diagnosis showed strong to excellent correlation both inter- and intraobserver MMS vs PACS when using the Weber (0.815, 0.988), Anatomical (0.858, 0.988), and AO classification systems (0.855, 0.985). MMS was less reliable than PACS in determining many management options. CONCLUSION: The reliability of ankle fracture classification using MMS image viewing was not significantly different to interpretation on PACS workstations. Smartphone use in ankle fracture classification is supported by this study. Smartphone use was less accurate than PACS in devising management plans and future use should be limited to making only initial plans that must be corroberated with PACS and intraoperative findings prior to definitive fixation.


Asunto(s)
Fracturas de Tobillo , Teléfono Inteligente , Fracturas de Tobillo/diagnóstico por imagen , Fracturas de Tobillo/cirugía , Humanos , Multimedia , Radiografía , Reproducibilidad de los Resultados
13.
Metab Eng ; 67: 387-395, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34365009

RESUMEN

Carbon loss in the form of CO2 is an intrinsic and persistent challenge faced during conventional and advanced biofuel production from biomass feedstocks. Current mechanisms for increasing carbon conservation typically require the provision of reduced co-substrates as additional reducing equivalents. This need can be circumvented, however, by exploiting the natural heterogeneity of lignocellulosic sugars mixtures and strategically using specific fractions to drive complementary CO2 emitting vs. CO2 fixing pathways. As a demonstration of concept, a coculture-coproduction system was developed by pairing two catabolically orthogonal Escherichia coli strains; one converting glucose to ethanol (G2E) and the other xylose to succinate (X2S). 13C-labeling studies reveled that G2E + X2S cocultures were capable of recycling 24% of all evolved CO2 and achieved a carbon conservation efficiency of 77%; significantly higher than the 64% achieved when all sugars are instead converted to just ethanol. In addition to CO2 exchange, the latent exchange of pyruvate between strains was discovered, along with significant carbon rearrangement within X2S.


Asunto(s)
Dióxido de Carbono , Carbono , Técnicas de Cocultivo , Fermentación , Glucosa , Xilosa
14.
Appl Microbiol Biotechnol ; 105(3): 1147-1158, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33443634

RESUMEN

With the goal of expanding the diversity of tools available for controlling gene expression in cyanobacteria, the T7-RNA polymerase gene expression system from E. coli BL21(DE3) was adapted and systematically engineered for robust function Synechococcus sp. PCC 7002, a fast-growing saltwater strain. Expression of T7-RNA polymerase was controlled via LacI regulation, while functionality was optimized by both further tuning its expression level along with optimizing the translation initiation region of the expressed gene, in this case an enhanced YFP reporter. Under high CO2 conditions, the resulting system displayed a 60-fold dynamic range in expression levels. Furthermore, when maximally induced, T7-RNA polymerase-dependent protein production constituted up to two-thirds of total cellular protein content in Synechococcus sp. PCC 7002. Ultimately, however, this came at the cost of 40% reductions in both biomass and pigmentation levels. Taken together, the developed T7-RNA polymerase gene expression system is effective for controlling and achieving high-level expression of heterologous genes in Synechococcus sp. PCC 7002, making it a valuable tool for cyanobacterial research. KEY POINTS: • Promoter driving T7-RNA polymerase was optimized. • Up to 60-fold dynamic range in expression, depending on CO2 conditions. • Two-thirds of total protein is T7-RNA polymerase dependent.


Asunto(s)
Synechococcus , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Fenotipo , Synechococcus/genética , Synechococcus/metabolismo
15.
J Ind Microbiol Biotechnol ; 48(1-2)2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33640981

RESUMEN

The global transcriptional response of Escherichia coli to styrene and potential influence of exposure source was determined by performing RNA sequencing (RNA-seq) analysis on both styrene-producing and styrene-exposed cells. In both cases, styrene exposure appears to cause both cell envelope and DNA damage, to which cells respond by down-regulating key genes/pathways involved in DNA replication, protein production, and cell wall biogenesis. Among the most significantly up-regulated genes were those involved with phage shock protein response (e.g. pspABCDE/G), general stress regulators (e.g. marA, rpoH), and membrane-altering genes (notably, bhsA, ompR, ldtC), whereas efflux transporters were, surprisingly, unaffected. Subsequent studies with styrene addition demonstrate how strains lacking ompR [involved in controlling outer membrane (OM) composition/osmoregulation] or any of tolQ, tolA, or tolR (involved in OM constriction) each displayed over 40% reduced growth relative to wild-type. Conversely, despite reducing basal fitness, overexpression of plsX (involved in phospholipid biosynthesis) led to 70% greater growth when styrene exposed. These collective differences point to the likely importance of OM properties in controlling native styrene tolerance. Overall, the collective behaviours suggest that, regardless of source, prolonged exposure to inhibitory styrene levels causes cells to shift from'growth mode' to 'survival mode', redistributing cellular resources to fuel native tolerance mechanisms.


Asunto(s)
Escherichia coli/efectos de los fármacos , Estireno/farmacología , Transcripción Genética , Tolerancia a Medicamentos , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , ARN Bacteriano/genética
16.
Protein Expr Purif ; 175: 105716, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32738437

RESUMEN

The high-flux/low-affinity cyanobacterial bicarbonate transporter BicA is a member of sulfate permease/solute carrier 26 (SulP/SLC26) family and plays a major role in cyanobacterial inorganic carbon uptake. In order to study this important membrane protein, robust platforms for over-expression and protocols for purification are required. In this work we have optimized the expression and purification of BicA from strain Synechocystis sp. PCC 6803 (BicA6803) in Escherichia coli. It was determined that expression with C43 (DE3) Rosetta2 at 37 °C produced the highest levels of over-expressed BicA6803 relative to other strains screened, and membrane solubilization with n-dodecyl-ß-d-maltopyranoside facilitated the purification of high levels of stable and homogenous BicA6803. Using these expression and purification strategies, the final yields of purified BicA were 6.5 ± 1.0 mg per liter of culture.


Asunto(s)
Proteínas Bacterianas , Expresión Génica , Simportadores de Sodio-Bicarbonato , Synechocystis/genética , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Simportadores de Sodio-Bicarbonato/biosíntesis , Simportadores de Sodio-Bicarbonato/química , Simportadores de Sodio-Bicarbonato/genética , Simportadores de Sodio-Bicarbonato/aislamiento & purificación , Synechocystis/metabolismo
17.
Eur Arch Psychiatry Clin Neurosci ; 270(5): 633-642, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30923939

RESUMEN

Variants in three genes coding for components of the serotonergic system, the tryptophan hydroxylase 1 (TPH1) rs1799913, serotonin transporter (SLC6A4) 5-HTTLPR, and serotonin receptor 2A (HTR2A) rs6311, were evaluated for association with suicidal ideation (SI) and with recovery from SI in a psychiatric inpatient population. Five hundred and eighty-two adult inpatients, including 390 patients who had SI, collected from December 2012 to April 2016 were assessed. SI recovery, calculated as change in SI between the first two-week period after admission and weeks 5 and 6, was appraised for association with the three variants. In this preliminary study, both TPH1 and 5-HTTLPR genotypes were associated with recovery (TPH1: recessive model, increased recovery with AC genotype, P = 0.026; additive model, increased recovery with AC genotype, P = 0.037; 5-HTTLPR: recessive model, increased recovery with AC, P = 0.043). When patients with comorbid alcohol use disorder (AUD) were removed, given that TPH1 has been associated with alcoholism, the associations of those recovered from SI with TPH1 rs1799913 remained significant for the additive (increased recovery with AC, P = 0.045) and recessive (increased recovery with C-carriers, P = 0.008) models, and with 5-HTTLPR using the dominant model (increased recovery with S'S', P = 0.016). In females, an association of SI recovery with TPH1 rs1799913 was found using a recessive model (increased recovery with C-carriers, P = 0.031), with 5-HTTLPR using additive (increased recovery with L'S', P = 0.048) and recessive (increased recovery with S'S', P = 0.042) models. Additionally, an association of SI with TPH1 rs1799913 was found in females using both additive (increased risk in AC, P = 0.033) and recessive (increased risk in C-carriers, P = 0.043) models, and with 5-HTTLPR using a recessive model (increased risk in S'S', P = 0.030). This study provides evidence that variation in the TPH1 and serotonin transporter genes play key roles in moderating recovery from SI during treatment in an inpatient psychiatric clinic.


Asunto(s)
Hospitales Psiquiátricos , Pacientes Internos , Trastornos Mentales/genética , Trastornos Mentales/terapia , Evaluación de Resultado en la Atención de Salud , Ideación Suicida , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Genéticos , Receptor de Serotonina 5-HT2A , Proteínas de Transporte de Serotonina en la Membrana Plasmática , Factores Sexuales , Triptófano Hidroxilasa , Adulto Joven
18.
Am J Drug Alcohol Abuse ; 46(2): 184-193, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31914324

RESUMEN

Background: The α1 antagonist doxazosin reduces cocaine use in individuals with cocaine use disorder (CUD) through a functional polymorphism of the α1 adrenoreceptor. The regulatory role of the α1adrenoreceptor subtype D (ADRA1D) gene polymorphism in CUD is uncharacterized.Objectives: To study how the genetic variant of ADRA1D gene (T1848A, rs2236554) may affect the treatment efficacy of doxazosin in reducing cocaine use.Methods: This 12-week pilot trial included 76 participants with CUD with ADRA1D (T1848A, rs2236554) AA (N = 40) or AT/TT genotype (N = 36). Participants were randomized to doxazosin (8 mg/day, N = 47) or placebo (N = 29), and followed with thrice weekly urine toxicology and once weekly cognitive behavioral psychotherapy.Results: The AA and the AT/TT groups had comparable baseline rates of cocaine positive urines at weeks 1-2 (~ 76%). In the placebo group, an increase of cocaine positive urines in the AT/TT group was found as compared to the AA group (24% vs. 9%). In the doxazosin group, a greater decrease in cocaine positive urines was found in the AT/TT group relative to the AA group. The difference between the doxazosin and placebo groups in cocaine negative urines became evident at weeks 5-6 and peaked at weeks 9-10 (~35% difference). The AT/TT group demonstrated a significant medication and time by medication effect (p < .001), whereas the AA group did not.Conclusion: The T-allele carriers showed a greater reduction of cocaine use after treatment with doxazosin in participants with the ADRA1D gene polymorphism (T1848A), suggesting that this SNP may serve as a pharmacogenetic marker in pharmacotherapy of CUD.


Asunto(s)
Trastornos Relacionados con Cocaína/tratamiento farmacológico , Doxazosina/uso terapéutico , Receptores Adrenérgicos alfa 1/genética , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapéutico , Adulto , Trastornos Relacionados con Cocaína/terapia , Terapia Cognitivo-Conductual , Terapia Combinada , Método Doble Ciego , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Farmacogenética , Proyectos Piloto , Polimorfismo Genético/genética
19.
Appl Environ Microbiol ; 85(6)2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30635383

RESUMEN

Efficient microbial conversion of lignocellulose into valuable products is often hindered by the presence of furfural, a dehydration product of pentoses in hemicellulose sugar syrups derived from woody biomass. For a cost-effective lignocellulose microbial conversion, robust biocatalysts are needed that can tolerate toxic inhibitors while maintaining optimal metabolic activities. A comprehensive plasmid-based library encoding native multidrug resistance (MDR) efflux pumps, porins, and select exporters from Escherichia coli was screened for furfural tolerance in an ethanologenic E. coli strain. Small multidrug resistance (SMR) pumps, such as SugE and MdtJI, as well as a lactate/glycolate:H+ symporter, LldP, conferred furfural tolerance in liquid culture tests. Expression of the SMR pump potentially increased furfural efflux and cellular viability upon furfural assault, suggesting novel activities for SMR pumps as furfural efflux proteins. Furthermore, induced expression of mdtJI enhanced ethanol fermentative production of LY180 in the presence of furfural or 5-hydroxymethylfurfural, further demonstrating the applications of SMR pumps. This work describes an effective approach to identify useful efflux systems with desired activities for nonnative toxic chemicals and provides a platform to further enhance furfural efflux by protein engineering and mutagenesis.IMPORTANCE Lignocellulosic biomass, especially agricultural residues, represents an important potential feedstock for microbial production of renewable fuels and chemicals. During the deconstruction of hemicellulose by thermochemical processes, side products that inhibit cell growth and production, such as furan aldehydes, are generated, limiting cost-effective lignocellulose conversion. Here, we developed a new approach to increase cellular tolerance by expressing multidrug resistance (MDR) pumps with putative efflux activities for furan aldehydes. The developed plasmid library and screening methods may facilitate new discoveries of MDR pumps for diverse toxic chemicals important for microbial conversion.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Etanol/metabolismo , Furaldehído/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Bioprospección , Proteínas de Escherichia coli/genética , Fermentación , Furaldehído/análogos & derivados , Ingeniería Genética , Lignina/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética
20.
Addict Biol ; 24(3): 531-538, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29498170

RESUMEN

The α1 -adrenergic antagonist, doxazosin, has improved cocaine use disorder (CUD) presumably by blocking norepinephrine (NE) stimulation and reward from cocaine-induced NE increases. If the NE levels for release were lower, then doxazosin might more readily block this NE stimulation and be more effective. The NE available for release can be lower through a genetic polymorphism in dopamine ß-hydroxylase (DBH) (C-1021T, rs1611115), which reduces DßH's conversion of dopamine to NE. We hypothesize that doxazosin would be more effective in CUD patients who have these genetically lower DßH levels. This 12-week, double-blind, randomized, placebo-controlled trial included 76 CUD patients: 49 with higher DßH levels from the DBH CC genotype and 27 with lower DßH levels from T-allele carriers (CT or TT). Patients were randomized to doxazosin (8 mg/day, N = 47) or placebo (N = 29) and followed with thrice weekly urine toxicology and once weekly cognitive behavioral psychotherapy. Cocaine use was reduced at a higher rate among patients in the doxazosin than in the placebo arm. We found significantly lower cocaine use rates among patients carrying the T-allele (CT/TT) than the CC genotype. The percentage of cocaine positive urines was reduced by 41 percent from baseline in the CT/TT group with low DßH and NE levels, as compared with no net reduction in the CC genotype group with normal DßH and NE levels. The DBH polymorphism appears play an important role in CUD patients' response to doxazosin treatment, supporting a pharmacogenetic association and potential application for personalized medicine.


Asunto(s)
Antagonistas de Receptores Adrenérgicos alfa 1/uso terapéutico , Trastornos Relacionados con Cocaína/rehabilitación , Dopamina beta-Hidroxilasa/genética , Doxazosina/uso terapéutico , Polimorfismo Genético/genética , Método Doble Ciego , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/antagonistas & inhibidores , Resultado del Tratamiento
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