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1.
J Med Microbiol ; 73(7)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38995832

RESUMEN

Introduction. Persister cells are transiently non-growing antibiotic-tolerant bacteria that cause infection relapse, and there is no effective antibiotic therapy to tackle these infections.Gap statement. High-throughput assays in drug discovery are biased towards detecting drugs that inhibit bacterial growth rather than killing non-growing bacteria. A new and simple assay to discover such drugs is needed.Aim. This study aims to develop a simple and high-throughput assay to identify compounds with antimicrobial activity against persister cells and use it to identify molecular motifs with such activity.Methodology. We quantified Staphylococcus aureus persister cells by enumeration of colony forming units after 24 h ciprofloxacin treatment. We first quantified how the cell concentration, antibiotic concentration, growth phase and presence/absence of nutrients during antibiotic exposure affected the fraction of persister cells in a population. After optimizing these parameters, we screened the antimicrobial activity of compound fragments to identify molecular structures that have activity against persister cells.Results. Exponential- and stationary-phase cultures transferred to nutrient-rich media displayed a bi-phasic time-kill curve and contained 0.001-0.07% persister cells. A short rifampicin treatment resulted in 100% persister cells for 7 h, after which cells resumed activity and became susceptible. Stationary-phase cultures displayed a low but constant death rate but ultimately resulted in similarly low survival rates as the exponential-phase cultures after 24 h ciprofloxacin treatment. The persister phenotype was only maintained in most of the population for 24 h if cells were transferred to a carbon-free minimal medium before exposure to ciprofloxacin. Keeping cells starved enabled the generation of high concentrations of S. aureus cells that tolerate 50× MIC ciprofloxacin, and we used this protocol for rapid screening for biocidal antibiotics. We identified seven compounds from four structural clusters with activity against antibiotic-tolerant S. aureus. Two compounds were moderately cytotoxic, and the rest were highly cytotoxic.Conclusion. Transferring a stationary-phase culture to a carbon-free minimal medium for antimicrobial testing is a simple strategy for high-throughput screening for new antibiotics that kill persister cells. We identified molecule fragments with such activity, but further screening is needed to identify motifs with lower general cytotoxicity.


Asunto(s)
Antibacterianos , Ciprofloxacina , Ensayos Analíticos de Alto Rendimiento , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Staphylococcus aureus/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento/métodos , Antibacterianos/farmacología , Ciprofloxacina/farmacología , Viabilidad Microbiana/efectos de los fármacos
2.
AMA J Ethics ; 26(6): E463-471, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38833421

RESUMEN

Federal and state governments mandate some health care organizations to implement antibiotic stewardship programs (ASPs). Some early adopters developed model ASPs that have helped set industry standards; other benchmarks will likely be forged in subsequent regulation, legislation, and jurisprudence. This article considers how ASP designs can affect professional autonomy, especially of frontline antibiotic stewards who are usually physicians and pharmacists. This article also considers how ASP development and implementation might influence standards of care and malpractice liability.


Asunto(s)
Programas de Optimización del Uso de los Antimicrobianos , Responsabilidad Legal , Médicos , Autonomía Profesional , Humanos , Programas de Optimización del Uso de los Antimicrobianos/legislación & jurisprudencia , Médicos/ética , Mala Praxis/legislación & jurisprudencia , Antibacterianos/uso terapéutico , Farmacéuticos/ética , Nivel de Atención/ética
3.
Access Microbiol ; 5(6)2023.
Artículo en Inglés | MEDLINE | ID: mdl-37424545

RESUMEN

Brewery spent grain (BSG) has previously been exploited in bioremediation. However, detailed knowledge of the associated bacterial community dynamics and changes in relevant metabolites and genes over time is limited. This study investigated the bioremediation of diesel contaminated soil amended with BSG. We observed complete degradation of three total petroleum hydrocarbon (TPH C10-C28) fractions in amended treatments as compared to one fraction in the unamended, natural attenuation treatments. The biodegradation rate constant (k) was higher in amended treatments (0.1021k) than in unamended (0.059k), and bacterial colony forming units increased significantly in amended treatments. The degradation compounds observed fitted into the elucidated diesel degradation pathways and quantitative PCR results showed that the gene copy numbers of all three associated degradation genes, alkB, catA and xylE, were significantly higher in amended treatments. High-throughput sequencing of 16S rRNA gene amplicons showed that amendment with BSG enriched autochthonous hydrocarbon degraders. Also, community shifts of the genera Acinetobacter and Pseudomonas correlated with the abundance of catabolic genes and degradation compounds observed. This study showed that these two genera are present in BSG and thus may be associated with the enhanced biodegradation observed in amended treatments. The results suggest that the combined evaluation of TPH, microbiological, metabolite and genetic analysis provides a useful holistic approach to assessing bioremediation.

4.
J Pharm Pharmacol ; 75(6): 758-763, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36879406

RESUMEN

OBJECTIVES: Within mammalian pancreatic islets, there are two major endocrine cell types, beta-cells which secrete insulin and alpha-cells which secrete glucagon. Whereas, insulin acts to lower circulating glucose, glucagon counters this by increasing circulating glucose via the mobilisation of glycogen. Synthalin A (Syn A) was the subject of much research in the 1920s and 1930s as a potential pancreatic alpha-cell toxin to block glucagon secretion. However, with the discovery of insulin and its lifesaving use in patients with diabetes, research on Syn-A was discontinued. KEY FINDINGS: This short review looks back on early studies performed with Syn A in animals and humans with diabetes. These are relevant today because both type 1 and type 2 diabetes are now recognised as states of not only insulin deficiency but also glucagon excess. SUMMARY: Lessons learned from this largely forgotten portfolio of work and therapeutic strategy aimed at limiting the number or function of islet alpha-cells might be worthy of reconsideration.


Asunto(s)
Diabetes Mellitus Tipo 2 , Islotes Pancreáticos , Animales , Humanos , Glucagón/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Glucosa/metabolismo , Mamíferos/metabolismo
6.
J Cancer Res Clin Oncol ; 149(8): 5007-5023, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36319895

RESUMEN

PURPOSE: Sonodynamic therapy (SDT) is emerging as a cancer treatment alternative with significant advantages over conventional therapies, including its minimally invasive and site-specific nature, its radical antitumour efficacy with minimal side effects, and its capacity to raise an antitumour immune response. The study explores the efficacy of SDT in combination with nanotechnology against pancreatic ductal adenocarcinoma. METHODS: A nanoparticulate formulation (HPNP) based on a cathepsin B-degradable glutamate-tyrosine co-polymer that carries hematoporphyrin was used in this study for the SDT-based treatment of PDAC. Cathepsin B levels in BxPC-3 and PANC-1 cells were correlated to cellular uptake of HPNP. The HPNP efficiency to induce a sonodynamic effect at varying ultrasound parameters, and at different oxygenation and pH conditions, was investigated. The biodistribution, tumour accumulation profile, and antitumour efficacy of HPNP in SDT were examined in immunocompetent mice carrying bilateral ectopic murine pancreatic tumours. The immune response profile of excised tumour tissues was also examined. RESULTS: The HPNP formulation significantly improved cellular uptake of hematoporphyrin for both BxPC-3 and PANC-1 cells, while increase of cellular uptake was positively correlated in PANC-1 cells. There was a clear SDT-induced cytotoxicity at the ultrasound conditions tested, and the treatment impaired the capacity of both BxPC-3 and PANC-1 cells to form colonies. The overall acoustic energy and pulse length, rather than the power density, were key in eliciting the effects observed in vitro. The SDT treatment in combination with HPNP resulted in 21% and 27% reduction of the target and off-target tumour volumes, respectively, within 24 h. A single SDT treatment elicited an antitumour effect that was characterized by an SDT-induced decrease in immunosuppressive T cell phenotypes. CONCLUSION: SDT has significant potential to serve as a monotherapy or adjunctive treatment for inoperable or borderline resectable PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Terapia por Ultrasonido , Animales , Ratones , Catepsina B , Terapia por Ultrasonido/métodos , Distribución Tisular , Neoplasias Pancreáticas/terapia , Hematoporfirinas/farmacología , Carcinoma Ductal Pancreático/terapia , Nanotecnología , Línea Celular Tumoral , Especies Reactivas de Oxígeno , Neoplasias Pancreáticas
7.
Adv Sci (Weinh) ; 9(34): e2203544, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36285697

RESUMEN

Nanocrystalline and nanotwinned materials achieve exceptional strengths through small grain sizes. Due to large areas of crystal interfaces, they are highly susceptible to grain growth and creep deformation, even at ambient temperatures. Here, ultrahigh strength nanotwinned copper microstructures have been stabilized against high temperature exposure while largely retaining electrical conductivity. By incorporating less than 1 vol% insoluble tungsten nanoparticles by a novel hybrid deposition method, both the ease of formation and the high temperature stability of nanotwins are dramatically enhanced up to at least 400 °C. By avoiding grain coarsening, improved high temperature creep properties arise as the coherent twin boundaries are poor diffusion paths, while some size-based nanotwin strengthening is retained. Such microstructures hold promise for more robust microchip interconnects and stronger electric motor components.

8.
Peptides ; 157: 170877, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36108978

RESUMEN

Absolute or relative hyperglucagonaemia is a characteristic of both Type 1 and Type 2 diabetes, resulting in fasting hyperglycaemia due in part to increased hepatic glucose production and lack of postprandial suppression of circulating glucagon concentrations. Consequently, therapeutics that target glucagon secretion or biological action may be effective antidiabetic agents. In this regard, specific glucagon receptor (GCGR) antagonists have been developed that exhibit impressive glucose-lowering actions, but unfortunately may cause off-target adverse effects in humans. Further to this, several currently approved antidiabetic agents, including GLP-1 mimetics, DPP-4 inhibitors, metformin, sulphonylureas and pramlintide likely exert part of their glucose homeostatic actions through direct or indirect inhibition of GCGR signalling. In addition to agents that inhibit the release of glucagon, compounds that enhance the transdifferentiation of glucagon secreting alpha-cells towards an insulin positive beta-cell phenotype could also help curb excess glucagon secretion in diabetes. Use of alpha-cell toxins represents another possible strategy to address hyperglucagonaemia in diabetes. In that respect, research from the 1920 s with diguanides such as synthalin A demonstrated effective glucose-lowering with alpha-cell ablation in both animal models and humans with diabetes. However, further clinical use of synthalin A was curtailed due its adverse effects and the increased availability of insulin. Overall, these observations with therapeutics that directly target alpha-cells, or GCGR signaling, highlight a largely untapped potential for diabetes therapy that merits further detailed consideration.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Metformina , Animales , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Glucagón/uso terapéutico , Péptido 1 Similar al Glucagón/uso terapéutico , Glucosa , Guanidinas , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Metformina/uso terapéutico , Receptores de Glucagón/genética
9.
Cancer Lett ; 517: 88-95, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34119606

RESUMEN

The emergence of immune checkpoint inhibitors (ICI's) in the past decade has proven transformative in the area of immuno-oncology. The PD-1/PD-L1 axis has been particularly well studied and monoclonal antibodies developed to block either the receptor (anti PD-1) or its associated ligand (anti PD-L1) can generate potent anti-tumour immunity in certain tumour models. However, many "immune cold" tumours remain unresponsive to ICI's and strategies to stimulate the adaptive immune system and make these tumours more susceptible to ICI treatment are currently under investigation. Sonodynamic therapy (SDT) is a targeted anti-cancer treatment that uses ultrasound to activate a sensitiser with the resulting generation of reactive oxygen species (ROS) causing direct cell death by apoptosis and necrosis. SDT has also been shown to stimulate the adaptive immune system in a pre-clinical model of colorectal cancer. In this manuscript, we investigate the ability of microbubble mediated SDT to control tumour growth in a bilateral tumour mouse model of pancreatic cancer by treating the target tumour with SDT and observing the effects at the off-target untreated tumour. The results demonstrated a significant 287% decrease in tumour volume when compared to untreated animals 11 days following the initial treatment with SDT, which reduced further to 369% when SDT was combined with anti-PD-L1 ICI treatment. Analysis of residual tumour tissues remaining after treatment revealed increased levels of infiltrating CD4+ and CD8+ T-lymphocytes (respectively 4.65 and 3.16-fold more) in the off-target tumours of animals where the target tumour was treated with SDT and anti-PD-L1, when compared to untreated tumours. These results suggest that SDT treatment elicits an adaptive immune response that is potentiated by the anti-PD-L1 ICI in this particular model of pancreatic cancer.


Asunto(s)
Antígeno B7-H1/inmunología , Inhibidores de Puntos de Control Inmunológico/inmunología , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/terapia , Animales , Anticuerpos Monoclonales/inmunología , Apoptosis/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/inmunología
10.
Eur J Pharm Biopharm ; 163: 49-59, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33798727

RESUMEN

Sonodynamic therapy (SDT) is an emerging stimulus-responsive approach for the targeted treatment of solid tumours. However, its ability to generate stimulus-responsive cytotoxic reactive oxygen species (ROS), is compromised by tumour hypoxia. Here we describe a robust means of preparing a pH-sensitive polymethacrylate-coated CaO2 nanoparticle that is capable of transiently alleviating tumour hypoxia. Systemic administration of particles to animals bearing human xenograft BxPC3 pancreatic tumours increases oxygen partial pressures (PO2) to 20-50 mmHg for over 40 min. RT-qPCR analysis of expression of selected tumour marker genes in treated animals suggests that the transient production of oxygen is sufficient to elicit effects at a molecular genetic level. Using particles labelled with the near infra-red (nIR) fluorescent dye, indocyanine green, selective uptake of particles by tumours was observed. Systemic administration of particles containing Rose Bengal (RB) at concentrations of 0.1 mg/mg of particles are capable of eliciting nanoparticle-induced, SDT-mediated antitumour effects using the BxPC3 human pancreatic tumour model in immuno-compromised mice. Additionally, a potent abscopal effect was observed in off-target tumours in a syngeneic murine bilateral tumour model for pancreatic cancer and an increase in tumour cytotoxic T cells (CD8+) and a decrease in immunosuppressive tumour regulatory T cells [Treg (CD4+, FoxP3+)] was observed in both target and off-target tumours in SDT treated animals. We suggest that this approach offers significant potential in the treatment of both focal and disseminated (metastatic) pancreatic cancer.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos/química , Neoplasias Pancreáticas/tratamiento farmacológico , Fotoquimioterapia/métodos , Terapia por Ultrasonido/métodos , Animales , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Modelos Animales de Enfermedad , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Ratones , Microburbujas , Nanopartículas/química , Oxígeno/farmacocinética , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/metabolismo , Rosa Bengala/administración & dosificación , Rosa Bengala/farmacocinética , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Front Reprod Health ; 3: 719326, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36303988

RESUMEN

Objective: Small non-coding RNAs, known as microRNAs (miRNAs), have emerging regulatory functions within the ovary that have been related to fertility. This study was undertaken to determine if circulating miRNAs reflect the changes associated with the parameters of embryo development and fertilization. Methods: In this cross-sectional pilot study. Plasma miRNAs were collected from 48 sequentially presenting women in the follicular phase prior to commencing in vitro fertilization (IVF). Circulating miRNAs were measured using locked nucleic acid (LNA)-based quantitative PCR (qPCR), while an updated miRNA data set was used to determine their level of expression. Results: Body mass index and weight were associated with the miRNAs let7b-3p and miR-375, respectively (p < 0.05), with the same relationship being found between endometrium thickness at oocyte retrieval and miR-885-5p and miR-34a-5p (p < 0.05). In contrast, miR-1260a was found to be inversely associated with anti-Mullerian hormone (AMH; p = 0.007), while miR-365a-3p, miR122-5p, and miR-34a-5p correlated with embryo fertilization rates (p < 0.05). However, when omitting cases of male infertility (n = 15), miR122-5p remained significant (p < 0.05), while miR-365a-3p and miR-34a-5p no longer differed; interestingly, however, miR1260a and mir93.3p became significant (p = 0.0087/0.02, respectively). Furthermore, age was negatively associated with miR-335-3p, miR-28-5p, miR-155-5p, miR-501-3p, and miR-497-5p (p < 0.05). Live birth rate was negatively associated with miR-335-3p, miR-100-5p, miR-497-5p, let-7d, and miR-574-3p (p < 0.05), but these were not significant when age was accounted for.However, with the exclusion of male factor infertility, all those miRNAs were no longer significant, though miR.150.5p emerged as significant (p = 0.042). A beta-regression model identified miR-1260a, miR-486-5p, and miR-132-3p (p < 0.03, p = 0.0003, p < 0.00001, respectively) as the most predictive for fertilization rate. Notably, changes in detectable miRNAs were not linked to cleavage rate, top quality embryos (G3D3), and blastocyst or antral follicle count. An ingenuity pathway analysis showed that miRNAs associated with age were also associated with the variables found in reproductive system diseases. Conclusion: Plasma miRNAs prior to the IVF cycle were associated with differing demographic and IVF parameters, including age, and may be predictive biomarkers of fertilization rate.

12.
Front Endocrinol (Lausanne) ; 11: 571357, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33101204

RESUMEN

Background: Small noncoding microRNA (miRNA) have regulatory functions in polycystic ovary syndrome (PCOS) that differ to those in women without PCOS. However, little is known about miRNA expression in women with PCOS who are not insulin resistant (IR). Methods: Circulating miRNAs were measured using quantitative polymerase chain reaction (qPCR) in 24 non-obese BMI and age matched women with PCOS and 24 control women. A miRNA data set was used to determine miRNA levels. Results: Women with PCOS showed a higher free androgen index (FAI) and anti-mullerian hormone (AMH) but IR did not differ. Four miRNAs (miR-1260a, miR-18b-5p, miR-424-5p, and miR let-7b-3p) differed between control and PCOS women that passed the false discovery rate (FDR) out of a total of 177 circulating miRNAs that were detected. MiRNA let-7b-3p correlated with AMH in PCOS (p < 0.05). When the groups were combined, miR-1260a correlated with FAI and let-7b-3p correlated with body mass index (BMI) (p < 0.05). There was no correlation to androgen levels. Ingenuity pathway analysis showed that nine of the top 10 miRNAs reported were associated with inflammatory pathways. Conclusion: When IR did not differ between PCOS and control women, only four miRNA differed significantly suggesting that IR may be a driver for many of the miRNA changes reported. Let-7b-3p was related to AMH in PCOS, and to BMI as a group, whilst miR-1260a correlated with FAI. Androgen levels, however, had no effect upon circulating miRNA profiles. The expressed miRNAs were associated with the inflammatory pathway involving TNF and IL6.


Asunto(s)
MicroARN Circulante/sangre , MicroARN Circulante/genética , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/genética , Adulto , Hormona Antimülleriana/sangre , Biomarcadores/sangre , Estudios de Cohortes , Femenino , Redes Reguladoras de Genes/fisiología , Humanos , Proyectos Piloto , Síndrome del Ovario Poliquístico/diagnóstico , Estudios Prospectivos , Adulto Joven
13.
Waste Manag ; 118: 302-312, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32919349

RESUMEN

This paper presents downstream cost-benefit analysis for electronic waste (e-waste) recycling workers in Pakistan, a country that both generates large quantities of e-waste domestically and imports a significant amount from developed countries. Financial cost-benefit elements - reduction in productive capacity, lost wages, medical expenses, wages (and meals) and non-financial cost-benefit elements - opportunity cost, cost of illiteracy and value of life have been quantified. Primary data collected on site was analyzed using quantitative and qualitative methods. The estimated total net economic cost to recycling workers is between Rs.34,069 and Rs.85,478 (US$ 203-5101) per month or an average of Rs.50,363 (US$ 300) per worker. This main finding suggests that cost exceeds by 2.6-4.7 times the estimated economic benefits derived by these workers. Related qualitative data suggests government and owners of recycling businesses are largely blind to many of the less visible costs of this industry, while recycling workers and their families appear trapped in a vicious cycle of poverty. Understanding that what can be measured can be managed and improved, a systematic assessment of informal recycling based on identified impact factors may help mitigate and ideally also motivate a shift towards formal processing that would reduce the downstream negative impacts, both visible and hidden.


Asunto(s)
Residuos Electrónicos , Administración de Residuos , Análisis Costo-Beneficio , Humanos , Industrias , Pakistán , Reciclaje
14.
J Control Release ; 326: 192-202, 2020 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-32653503

RESUMEN

The major unmet need and crucial challenge hampering the exciting potential of RNAi therapeutics in ophthalmology is to find an effective, safe and non-invasive means of delivering siRNA to the cornea. Although all tissues of the eye are accessible by injection, topical application is preferable for the frequent treatment regimen that would be necessary for siRNA-induced gene silencing. However, the ocular surface is one of the more complex biological barriers for drug delivery due to the combined effect of short contact time, tear dilution and poor corneal cell penetration. Using nanotechnology to overcome the challenges, we developed a unique silicon-based delivery platform for ocular delivery of siRNA. This biocompatible hybrid of porous silicon nanoparticles and lipids has demonstrated an ability to bind nucleic acid and deliver functional siRNA to corneal cells both in vitro and in vivo. Potent transfection of human corneal epithelial cells with siRNA-ProSilic® formulation was followed by a successful downregulation of reporter protein expression. Moreover, siRNA complexed with this silicon-based hybrid and applied in vivo topically to mice eyes penetrated across all cornea layers and resulted in a significant reduction of the targeted protein expression in corneal epithelium. In terms of siRNA loading capacity, system versatility, and potency of action, ProSilic provides unique attributes as a biodegradable delivery platform for therapeutic oligonucleotides.


Asunto(s)
Nanopartículas , Silicio , Córnea , Lípidos , ARN Interferente Pequeño
15.
Tissue Eng Part A ; 26(21-22): 1209-1221, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32515285

RESUMEN

In vitro cultures to be used in various analytical investigations of cardiomyocyte (CM) growth and function for enhancing insight into physiological and pathological mechanisms should closely express in vivo morphology. The aim of the studies is to explore how to use microfabrication and physical-cue-addition techniques to establish a neonatal rat CM culture model that expresses an end-to-end connected rod shape with in vivo-like intercalated discs (ICDs). Freshly isolated neonatal rat CMs were cultured on microgrooved polydimethylsiloxane substrate. Cell alignment and ICD orientation were evaluated using confocal fluorescence and transmission electron microscopy under various combinations of different culture conditions. Cyclic stretch and blebbistatin tests were conducted to explore mechanical and electrical effects. Laboratory-made MATLAB software was developed to quantify cell alignment and ICD orientation. Our results demonstrate that the mechanical effect associated with the electrical stimulation may contribute to step-like ICD formation viewed from the top. In addition, our study reveals that a suspended elastic substrate that was slack with scattered folds, not taut, enabled CM contraction of equal strength on both apical and basal cell surfaces, allowing the cultured CMs to express a three-dimensional rod shape with disc-like ICDs viewed cross-sectionally. Impact statement In this article, we describe how the tugging forces generated by cardiomyocytes (CMs) facilitate the formation of the morphology of the intercalated discs (ICDs) to achieve mechanoelectrical coupling between CMs. Correspondingly, we report experimental techniques we developed to enable the in vivo-like behavior of the tugging forces to support the development of in vivo-like morphology in ICDs. These techniques will enhance insight into physiological and pathological mechanisms related to the development of tissue-engineered cardiac constructs in various analytical investigations of CM growth and function.


Asunto(s)
Miocardio , Miocitos Cardíacos , Animales , Células Cultivadas , Miocitos Cardíacos/citología , Ratas , Estrés Mecánico , Ingeniería de Tejidos
16.
West J Emerg Med ; 21(3): 653-659, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32421515

RESUMEN

INTRODUCTION: With the increasing influence of electronic health records in emergency medicine came concerns of decreasing operational efficiencies. Particularly worrisome was increasing patient length of stay (LOS). Medical scribes were identified to be in a good position to quickly address barriers to treatment delivery and patient flow. The objective of this study was to investigate patient LOS in the mid- and low-acuity zones of an academic emergency department (ED) with and without medical scribes. METHODS: A retrospective cohort study compared patient volume and average LOS between a cohort without scribes and a cohort after the implementation of a scribe-flow coordinator program. Patients were triaged to the mid-acuity Vertical Zone (primarily Emergency Severity Index [ESI] 3) or low-acuity Fast Track (primarily ESI 4 and 5) at a tertiary academic ED. Patients were stratified by treatment zone, acuity level, and disposition. RESULTS: The pre-intervention and post-intervention periods included 8900 patients and 9935 patients, respectively. LOS for patients discharged from the Vertical Zone decreased by 12 minutes from 235 to 223 minutes (p<0.0001, 95% confidence interval [CI], -17,-7) despite a 10% increase in patient volume. For patients admitted from the Vertical Zone, volume increased 13% and LOS remained almost the same, increasing from 225 to 228 minutes (p=0.532, 95% CI, -6,12). For patients discharged from the Fast Track, volume increased 14% and LOS increased six minutes, from 89 to 95 minutes (p<0.0001, 95% CI, 4,9). Predictably, only 1% of Fast Track patients were admitted. CONCLUSION: Despite substantially increased volume, the use of scribes as patient flow facilitators in the mid-acuity zone was associated with decreased LOS. In the low-acuity zone, scribes were not shown to be as effective, perhaps because rapid patient turnover required them to focus on documentation.


Asunto(s)
Documentación , Servicio de Urgencia en Hospital , Tiempo de Internación/estadística & datos numéricos , Grupo de Atención al Paciente/organización & administración , Alta del Paciente/estadística & datos numéricos , Centros Médicos Académicos , Adulto , Estudios de Cohortes , Documentación/métodos , Documentación/tendencias , Registros Electrónicos de Salud/estadística & datos numéricos , Servicio de Urgencia en Hospital/organización & administración , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Gravedad del Paciente , Estudios Retrospectivos , Triaje/métodos , Triaje/organización & administración , Estados Unidos
17.
ACS Chem Biol ; 14(12): 2859-2866, 2019 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-31670944

RESUMEN

Bacterial toxin-antitoxin (TA) systems, which are diverse and widespread among prokaryotes, are responsible for tolerance to drugs and environmental stresses. However, the low abundance of toxin and antitoxin proteins renders their quantitative measurement in single bacteria challenging. Employing a laboratory-built nano-flow cytometer (nFCM) to monitor a tetracysteine (TC)-tagged TA system labeled with the biarsenical dye FlAsH, we here report the development of a sensitive method that enables the detection of basal-level expression of antitoxin. Using the Escherichia coli MqsR/MqsA as a model TA system, we reveal for the first time that under its native promoter and in the absence of environmental stress, there exist two populations of bacteria with high or low levels of antitoxin MqsA. Under environmental stress, such as bile acid stress, heat shock, and amino acid starvation, the two populations of bacteria responded differently in terms of MqsA degradation and production. Subsequently, resumed production of MqsA after amino acid stress was observed for the first time. Taking advantage of the multiparameter capability of nFCM, bacterial growth rate and MqsA production were analyzed simultaneously. We found that under environmental stress, the response of bacterial growth was consistent with MqsA production but with an approximate 60 min lag. Overall, the results of the present study indicate that stochastic elevation of MqsA level facilitates bacterial survival, and the two populations with distinct phenotypes empower bacteria to deal with fluctuating environments. This analytical method will help researchers gain deeper insight into the heterogeneity and fundamental role of TA systems.


Asunto(s)
Antitoxinas/farmacología , Proteínas de Escherichia coli/metabolismo , Análisis de la Célula Individual/métodos , Aminoácidos/metabolismo , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Estrés Fisiológico
18.
Sci Rep ; 9(1): 16306, 2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31705013

RESUMEN

Several studies have shown the expression of small non-coding microRNA (miRNA) changes in PCOS and their expression in follicular fluid has been described, though the number of studies remains small. In this prospective cohort study, miRNA were measured using quantitative polymerase chain reaction (qPCR) in 29 weight and aged matched anovulatory women with PCOS and 30 women without from follicular fluid taken at the time of oocyte retrieval who were undergoing in vitro fertilization (IVF); miRNA levels were determined from a miRNA data set. 176 miRNA were detected, of which 29 differed significantly between normal women and PCOS women. Of these, the top 7 (p < 0.015) were miR-381-3p, miR-199b-5p, miR-93-3p, miR-361-3p, miR-127-3p, miR-382-5p, miR-425-3p. In PCOS, miR-382-5p correlated with age and free androgen index (FAI), miR-199b-5p correlated with anti-mullerian hormone (AMH) and miR-93-3p correlated with C-reactive protein (CRP). In normal controls, miR-127-3p, miR-382-5p and miR-425-3p correlated with the fertilisation rate; miR-127-3p correlated with insulin resistance and miR-381-3p correlated with FAI. Ingenuity pathway assessment revealed that 12 of the significantly altered miRNA related to reproductive pathways, 12 miRNA related to the inflammatory disease pathway and 6 were implicated in benign pelvic disease. MiRNAs differed in the follicular fluid between PCOS and normal control women, correlating with age, FAI, inflammation and AMH in PCOS, and with BMI, fertilization rate (3 miRNA), insulin resistance, FAI and inflammation in control women, according to Ingenuity Pathway Analysis.


Asunto(s)
MicroARN Circulante , Líquido Folicular/metabolismo , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Adulto , Biomarcadores , Estudios de Casos y Controles , Biología Computacional , Femenino , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , MicroARNs/genética , Recuperación del Oocito , Estudios Prospectivos
19.
Behav Res Ther ; 123: 103503, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31715324

RESUMEN

BACKGROUND: Anxiety and depression are common, debilitating and costly. These disorders are influenced by multiple risk factors, from genes to psychological vulnerabilities and environmental stressors, but research is hampered by a lack of sufficiently large comprehensive studies. We are recruiting 40,000 individuals with lifetime depression or anxiety and broad assessment of risks to facilitate future research. METHODS: The Genetic Links to Anxiety and Depression (GLAD) Study (www.gladstudy.org.uk) recruits individuals with depression or anxiety into the NIHR Mental Health BioResource. Participants invited to join the study (via media campaigns) provide demographic, environmental and genetic data, and consent for medical record linkage and recontact. RESULTS: Online recruitment was effective; 42,531 participants consented and 27,776 completed the questionnaire by end of July 2019. Participants' questionnaire data identified very high rates of recurrent depression, severe anxiety, and comorbidity. Participants reported high rates of treatment receipt. The age profile of the sample is biased toward young adults, with higher recruitment of females and the more educated, especially at younger ages. DISCUSSION: This paper describes the study methodology and descriptive data for GLAD, which represents a large, recontactable resource that will enable future research into risks, outcomes, and treatment for anxiety and depression.


Asunto(s)
Ansiedad/genética , Depresión/genética , Selección de Paciente , Desarrollo de Programa/métodos , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Femenino , Genotipo , Humanos , Internet , Masculino , Persona de Mediana Edad , Fenotipo , Trastornos Fóbicos/genética , Adulto Joven
20.
PLoS One ; 14(7): e0219042, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31314759

RESUMEN

Wide crosses between genetically diverged parents may reveal novel loci for crop improvement that are not apparent in crosses between elite cultivars. The landrace Chevallier was a noted malting barley first grown in 1820. To identify potentially novel alleles for agronomic traits, Chevallier was crossed with the modern malting cultivar NFC Tipple generating two genetically diverse recombinant inbred line populations. Genetic maps were produced using genotyping-by-sequencing and 384-SNP genotyping, and the populations were phenotyped for agronomic traits to allow the identification of quantitative trait loci (QTL). Within the semi-dwarf 1 (sdw1) region on chromosome 3H Chevallier conferred increased plant height and reduced tiller number, with QTL for these traits explaining 79.4% and 35.2% of the phenotypic variance observed, respectively. Chevallier was also associated with powdery mildew susceptibility, with a QTL on 1H accounting for up to 19.1% of the variance and resistance at this locus most likely resulting from an Mla variant from Tipple. Two novel QTL for physiological leaf spotting were identified on 3H and 7H, explaining up to 17.1% of the variance and with the Chevallier allele reducing symptom severity on 7H. Preliminary micromalting analysis was also undertaken to compare the malting characteristics of Chevallier and Tipple. Chevallier malt contained significantly lower levels of both α-amylase and wort ß-glucan than Tipple malt, however no significant differences were observed for the remaining malting parameters measured. This suggests that the most obvious improvements in barley since the introduction of Chevallier are for agronomic traits such as height, yield and lodging resistance rather than for malting characteristics. Overall, our results demonstrate that this wide cross between Chevallier and Tipple may provide a source of novel QTL for barley breeding.


Asunto(s)
Hordeum/genética , Bebidas Alcohólicas , Alelos , Mapeo Cromosómico , Productos Agrícolas/genética , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/fisiología , Cruzamientos Genéticos , Resistencia a la Enfermedad/genética , Genes de Plantas , Genotipo , Hordeum/crecimiento & desarrollo , Hordeum/fisiología , Fenotipo , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/prevención & control , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
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