RESUMEN
INTRODUCTION: A study on the quality of drinking water was conducted at Air Kuning Treatment Plant In Perak, Malaysia, based on a sanitary survey in 14 sampling points stations from the intake area to the auxiliary points. This was to ensure the continuous supply of clean and safe drinking water to the consumers for public health protection. The objective was to examine the physical, microbiological, and chemical parameters of the water, classification at each site based on National Drinking Water Standards (NDWQS) and to understand the spatial variation using environmetric technique; principal component analysis (PCA). MATERIALS AND METHODS: Water samples were subjected to in situ and laboratory water quality analyses and focused on pH, turbidity, chlorine, Escherichia coli, total coliform, total hardness, iron (Fe), aluminium (Al), zinc (Zn), magnesium (Mg) and sodium (Na). All procedures followed the American Public Health Association (APHA) testing procedures. RESULTS: Based on the results obtained, the values of each parameter were found to be within the safe limits set by the NDWQS except for total coliform and iron (Fe). PCA has indicated that turbidity, total coliform, E. coli, Na, and Al were the major factors that contributed to the drinking water contamination in river water intake. CONCLUSION: Overall, the water from all sampling point stations after undergoing water treatment process was found to be safe as drinking water. It is important to evaluate the drinking water quality of the treatment plant to ensure that consumers have access to safe and clean drinking water as well as community awareness on drinking water quality is essential to promote public health and environmental protection.
Asunto(s)
Agua Potable , Calidad del Agua , Humanos , Escherichia coli , Malasia , Hierro , Microbiología del AguaRESUMEN
INTRODUCTION: The first meeting of the Integration of Continuous Glucose Monitor Data into the Electronic Health Record (iCoDE) project, organized by Diabetes Technology Society, took place virtually on January 27, 2022. METHODS: Clinicians, government officials, data aggregators, attorneys, and standards experts spoke in panels and breakout groups. Three themes were covered: 1) why digital health data integration into the electronic health record (EHR) is needed, 2) what integrated continuously monitored glucose data will look like, and 3) how this process can be achieved in a way that will satisfy clinicians, healthcare organizations, and regulatory experts. RESULTS: The meeting themes were addressed within eight sessions: 1) What Do Inpatient Clinicians Want to See With Integration of CGM Data into the EHR?, 2) What Do Outpatient Clinicians Want to See With Integration of CGM Data into the EHR?, 3) Why Are Data Standards and Guidances Useful?, 4) What Value Can Data Integration Services Add?, 5) What Are Examples of Successful Integration?, 6) Which Privacy, Security, and Regulatory Issues Must Be Addressed to Integrate CGM Data into the EHR?, 7) Breakout Group Discussions, and 8) Presentation of Breakout Group Ideas. CONCLUSIONS: Creation of data standards and workflow guidance are necessary components of the Integration of Continuous Glucose Monitor Data into the Electronic Health Record (iCoDE) standard project. This meeting, which launched iCoDE, will be followed by a set of working group meetings intended to create the needed standard.
Asunto(s)
Diabetes Mellitus , Registros Electrónicos de Salud , Glucemia , Diabetes Mellitus/terapia , Humanos , Flujo de TrabajoRESUMEN
â¢Adherence can be broken into three processes: uptake, consistent use, and persistence.â¢Barriers and facilitators to NRT use vary over the three adherence processes.â¢Information gaps and negative stories about NRT are common barriers to adherence.â¢NRT adherence may be improved by addressing patient knowledge and concerns.
RESUMEN
A clinically-relevant, drug-resistant mutant of HIV-1 protease (PR), termed Flap+(I54V) and containing L10I, G48V, I54V and V82A mutations, is known to produce significant changes in the entropy and enthalpy balance of drug-PR interactions, compared to wild-type PR. A similar mutant, Flap+(I54A) , which evolves from Flap+(I54V) and contains the single change at residue 54 relative to Flap+(I54V) , does not. Yet, how Flap+(I54A) behaves in solution is not known. To understand the molecular basis of V54A evolution, we compared nuclear magnetic resonance (NMR) spectroscopy, fluorescence spectroscopy, isothermal titration calorimetry, and enzymatic assay data from four PR proteins: PR (pWT), Flap+(I54V) , Flap+(I54A) , and Flap+(I54) , a control mutant that contains only L10I, G48V and V82A mutations. Our data consistently show that selection to the smaller side chain at residue 54, not only decreases inhibitor affinity, but also restores the catalytic activity.
Asunto(s)
Farmacorresistencia Viral/genética , Inhibidores de la Proteasa del VIH/metabolismo , Proteasa del VIH , Calorimetría , Proteasa del VIH/química , Proteasa del VIH/genética , Proteasa del VIH/metabolismo , Inhibidores de la Proteasa del VIH/química , Modelos Moleculares , Mutación/genética , Resonancia Magnética Nuclear Biomolecular , Pepstatinas/química , Pepstatinas/metabolismo , Unión Proteica , TermodinámicaRESUMEN
This article describes the clinical course, radiological findings, and outcome of two patients with the novel 2019 coronavirus disease (COVID-19) who remained comatose for a prolonged duration following discontinuation of all sedation. These two male patients, one aged 59-years and another aged 53-years, both with a history of hypertension and neurologically intact on admission, developed worsening COVID-19 associated acute respiratory distress syndrome (ARDS). Both required benzodiazepine, opioid, neuromuscular blockade, therapeutic anticoagulation, and vasopressor infusions in addition to renal replacement therapy. Echocardiography demonstrated normal chamber size and systolic function in both cases. Each patient demonstrated only trace flexion to pain 7-10 days following discontinuation of all sedation. Magnetic Resonance Imaging on both patients demonstrated multifocal lesions on diffusion weighted imaging with apparent diffusion coefficient correlate in bilateral middle/anterior cerebral artery borderzones, and no large-vessel occlusion or severe stenosis. In both patients, continuous electroencephalography demonstrated no seizures. Neither patient had any documented period of sustained hypotension (mean arterial pressure <60 mmHg) or hypoxia (SpO2 <90%). Ninety days following initial presentation, the 59-years-old man was oriented, with fluent speech and able to ambulate with assistance, while the other 53-years-old man was at home and independent, undertaking the basic activities required by daily living. We conclude that critically-ill COVID-19 patients with prolonged coma following sedation discontinuation may demonstrate imaging features of ischemic injury in borderzone regions despite the absence of documented sustained hypotension or hypoxia. However, substantial neurological recovery is possible despite these findings.
RESUMEN
Every year, the poultry industry experiences significant economic losses due to epidemics of Newcastle disease virus (NDV). Developing new vaccines by identifying and using the immunogenic hemagglutinin-neuraminidase (HN) protein can protect the poultry industry. In the present study, the full-length HN protein was expressed in Escherichia coli (E. coli) BL21 (DE3) cells, purified via affinity chromatography and detected via western blot analysis using His-specific antibodies. The purified HN protein was further evaluated in chickens to study the immune response against NDV. The successful production of HN-specific IgY proved the activity of the purified HN protein. IgY was present in the serum of immunized chickens. However, the immune response was higher in chickens immunized with purified HN protein along with complete and incomplete adjuvants than in chickens immunized with only the HN protein. Keywords: protein; Newcastle disease virus; poultry; infectious diseases; vaccines.
Asunto(s)
Proteína HN/inmunología , Enfermedad de Newcastle , Vacunas Virales/inmunología , Animales , Pollos , Escherichia coli/genética , Proteína HN/genética , Enfermedad de Newcastle/prevención & control , Virus de la Enfermedad de Newcastle , Proteínas Recombinantes/inmunología , Vacunas Virales/genéticaRESUMEN
Plants have been as medicinal mediators for centuries. Recent trends in agro-biotechnology however, improved the therapeutic roles of plants to a significant level and introduced plant-based oral vaccine which can arouse an immune response in consumer. Although conventional vaccines against infectious diseases have been administrated for years the discovery of plant-based oral vaccines can potentially replace them completely in the future. The probable limitations in conventional vaccines are found to be overcome by plant-based oral vaccines. Humans and animals will no longer be dependent upon local or systemic administration of vaccines but they will just receive the vaccines as a routine food. For the purpose, gene of interest is introduced into plant through transformation, and expression of specific antigen is obtained in plant products which are then consumed by humans or animals. Therefore, plants can serve as bioreactors or bio-factories for production of edible vaccines. A detailed overview about edible vaccines, methods for edible vaccine production, candidate bioreactors and future perspectives of edible vaccines has been summarized in current article. The future of vaccination seems to be present within plant-based vaccination system. Keywords: vaccine; edible vaccine; infectious diseases; antigen; edible crops; oral immunization.
Asunto(s)
Control de Enfermedades Transmisibles , Vacunación , Vacunas , Administración Oral , Animales , Humanos , Plantas Modificadas Genéticamente , Vacunación/métodos , Vacunas/administración & dosificación , Vacunas ComestiblesRESUMEN
We report a method for growing rectangular InAs nanofins with deterministic length, width, and height by dielectric-templated selective-area epitaxy. These freestanding nanofins can be transferred to lay flat on a separate substrate for device fabrication. A key goal was to regain a spatial dimension for device design compared to nanowires, while retaining the benefits of bottom-up epitaxial growth. The transferred nanofins were made into devices featuring multiple contacts for Hall effect and four-terminal resistance studies, as well as a global back-gate and nanoscale local top-gates for density control. Hall studies give a 3D electron density 2.5-5 × 1017 cm-3, corresponding to an approximate surface accumulation layer density 3-6 × 1012 cm-2 that agrees well with previous studies of InAs nanowires. We obtain Hall mobilities as high as 1200 cm2/(V s), field-effect mobilities as high as 4400 cm2/(V s), and clear quantum interference structure at temperatures as high as 20 K. Our devices show excellent prospects for fabrication into more complicated devices featuring multiple ohmic contacts, local gates, and possibly other functional elements, for example, patterned superconductor contacts, that may make them attractive options for future quantum information applications.
RESUMEN
INTRODUCTION: Most smokers see a physician each year, but few use any assistance when they try to quit. Text messaging programs improve smoking cessation in community and school settings; however, their efficacy in a primary care setting is unclear. The current trial assesses the feasibility and preliminary clinical outcomes of text messaging and mailed nicotine replacement therapy (NRT) among smokers in primary care. METHODS: In this single-center pilot randomized trial, eligible smokers in primary care are offered brief advice by phone and randomly assigned to one of four interventions: (1) Brief advice only, (2) text messages targeted to primary care patients and tailored to quit readiness, (3) a 2-week supply of nicotine patches and/or lozenges (NRT), and (4) both text messaging and NRT. Randomization is stratified by practice and intention to quit. The text messages (up to 5/day) encourage those not ready to quit to practice a quit attempt, assist those with a quit date through a quit attempt, and promote NRT use. The 2-week supply of NRT is mailed to patients' homes. RESULTS: Feasibility outcomes include recruitment rates, study retention, and treatment adherence. Clinical outcomes are assessed at 1, 2, 6, and 12-weeks post-enrollment. The primary outcome is ≥1self-reported quit attempt(s). Secondary clinical outcomes include self-reported past 7- and 30-day abstinence, days not smoked, NRT adherence, and exhaled carbon monoxide. CONCLUSIONS: This pilot assesses text messaging plus NRT, as a proactively offered intervention for smoking cessation support in smokers receiving primary care and will inform full-scale randomized trial planning. TRIAL REGISTRATION: ClinicalTrials.govNCT03174158.
Asunto(s)
Atención Primaria de Salud/métodos , Agentes para el Cese del Hábito de Fumar/farmacología , Cese del Hábito de Fumar , Fumar , Envío de Mensajes de Texto , Dispositivos para Dejar de Fumar Tabaco , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Servicios Postales , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Fumar/psicología , Fumar/terapia , Cese del Hábito de Fumar/métodos , Cese del Hábito de Fumar/psicologíaRESUMEN
This manuscript presents an NMR strategy to investigate conformational differences in protein-inhibitor complexes, when the inhibitors tightly bind to a protein at sub-nanomolar dissociation constants and are highly analogous to each other. Using HIV-1 protease (PR), we previously evaluated amide chemical shift differences, ΔCSPs, of PR bound to darunavir (DRV) compared to PR bound to several DRV analogue inhibitors, to investigate subtle but significant long-distance conformation changes caused by the inhibitor's chemical moiety variation [Khan, S. N., Persons, J. D. Paulsen, J. L., Guerrero, M., Schiffer, C. A., Kurt-Yilmaz, N., and Ishima, R., Biochemistry, (2018), 57, 1652-1662]. However, ΔCSPs are not ideal for investigating subtle PR-inhibitor interface differences because intrinsic differences in the electron shielding of the inhibitors affect protein ΔCSPs. NMR relaxation is also not suitable as it is not sensitive enough to detect small conformational differences in rigid regions among similar PR-inhibitor complexes. Thus, to gain insight into conformational differences at the inhibitor-protein interface, we recorded 15N-half filtered NOESY spectra of PR bound to two highly analogous inhibitors and assessed NOEs between PR amide protons and inhibitor protons, between PR amide protons and hydroxyl side chains, and between PR amide protons and water protons. We also verified the PR amide-water NOEs using 2D water-NOE/ROE experiments. Differences in water-amide proton NOE peaks, possibly due to amide-protein hydrogen bonds, were observed between subunit A and subunit B, and between the DRV-bound form and an analogous inhibitor-bound form, which may contribute to remote conformational changes.
Asunto(s)
Proteasa del VIH/química , Resonancia Magnética Nuclear Biomolecular/métodos , Sitios de Unión/fisiología , Proteasa del VIH/análisis , Soluciones Farmacéuticas/análisis , Soluciones Farmacéuticas/química , Conformación Proteica , Estructura Secundaria de ProteínaRESUMEN
In the era of state-of-the-art inhibitor design and high-resolution structural studies, detection of significant but small protein structural differences in the inhibitor-bound forms is critical to further developing the inhibitor. Here, we probed differences in HIV-1 protease (PR) conformation among darunavir and four analogous inhibitor-bound forms and compared them with a drug-resistant mutant using nuclear magnetic resonance chemical shifts. Changes in amide chemical shifts of wild-type (WT) PR among these inhibitor-bound forms, ΔCSP, were subtle but detectable and extended >10 Å from the inhibitor-binding site, asymmetrically between the two subunits of PR. Molecular dynamics simulations revealed differential local hydrogen bonding as the molecular basis of this remote asymmetric change. Inhibitor-bound forms of the drug-resistant mutant also showed a similar long-range ΔCSP pattern. Differences in ΔCSP values of the WT and the mutant (ΔΔCSPs) were observed at the inhibitor-binding site and in the surrounding region. Comparing chemical shift changes among highly analogous inhibitors and ΔΔCSPs effectively eliminated local environmental effects stemming from different chemical groups and enabled exploitation of these sensitive parameters to detect subtle protein conformational changes and to elucidate asymmetric and remote conformational effects upon inhibitor interaction.
Asunto(s)
Farmacorresistencia Viral , Inhibidores de la Proteasa del VIH/química , Proteasa del VIH/química , Mutación , Resonancia Magnética Nuclear Biomolecular/métodos , Secuencia de Aminoácidos , Proteasa del VIH/efectos de los fármacos , Proteasa del VIH/genética , Simulación de Dinámica Molecular , Conformación ProteicaRESUMEN
More than 36 million people are living with human immunodeficiency virus (HIV) infection worldwide and 50% of them have access to antiretroviral therapy (ART). While recent advances in HIV therapy have reduced the viral load, restored CD4 T cell counts and decreased opportunistic infections, several bone-related abnormalities such as low bone mineral density (BMD), osteoporosis, osteopenia, osteomalacia and fractures have emerged in HIV-infected individuals. Of all classes of antiretroviral agents, HIV protease inhibitors used in ART combination showed a higher frequency of osteopenia, osteoporosis and low BMD in HIV-infected patients. Although the mechanisms of HIV and/or ART associated bone abnormalities are not known, it is believed that the damage is caused by a complex interaction of T lymphocytes with osteoclasts and osteoblasts, likely influenced by both HIV and ART. In addition, infection of osteoclasts and bone marrow stromal cells by HIV, including HIV Gp120 induced apoptosis of osteoblasts and release of proinflammatory cytokines have been implicated in impairment of bone development and maturation. Several of the newer antiretroviral agents currently used in ART combination, including the widely used tenofovir in different formulations show relative adverse effects on BMD. In this context, switching the HIV-regimen from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) showed improvement in BMD of HIV-infected patients. In addition, inclusion of integrase inhibitor in ART combination is associated with improved BMD in patients. Furthermore, supplementation of vitamin D and calcium with the initiation of ART may mitigate bone loss. Therefore, levels of vitamin D and calcium should be part of the evaluation of HIV-infected patients.
RESUMEN
HIV-1 is transmitted from mother-to-child (vertical transmission) at an estimated rate of approximately 30% without any antiretroviral therapy (ART). However, administration of ART during pregnancy considerably diminishes the rate of mother-to-child transmission of HIV-1, which has become a standard of perinatal care in HIV-infected pregnant females in developed countries. Moreover, a majority of children born to HIV-infected mothers are uninfected without any ART. In addition, characteristics of HIV-1 and/or cellular factors in the mothers may play a role in influencing or preventing vertical transmission. Several studies, including from our laboratory have characterized the properties of HIV-1 from infected mothers that transmitted HIV-1 to their infants (transmitting mothers) and compared with those mothers that failed to transmit HIV-1 to their infants (non-transmitting mothers) in the absence of ART. One of the striking differences observed was that the non-transmitting mothers harbored a less heterogeneous HIV-1 population than transmitting mothers in the analyzed HIV-1 regions of p17 gag, env V3, vif and vpr. The other significant and distinctive findings were that the functional domains of HIV-1 vif and vpr proteins were less conserved in non-transmitting mothers compared with transmitting mothers. Furthermore, there were differences seen in two important motifs of HIV-1 Gag p17, including conservation of QVSQNY motif and variation in KIEEEQN motif in non-transmitting mothers compared with transmitting mothers. Several of these distinguishing properties of HIV-1 in non-transmitting mothers provide insights in developing strategies for preventing HIV-1 vertical transmission.
RESUMEN
AIMS: To report health-related quality of life (HRQOL) and toxicity in prostate cancer patients treated with single-fraction high dose rate (HDR) brachytherapy boost and external beam radiotherapy (EBRT). MATERIALS AND METHODS: Patients with intermediate-risk prostate cancer were accrued to a phase II clinical trial of 15 Gy HDR boost and EBRT to a dose of 37.5 Gy in 15 fractions. HRQOL (Expanded Prostate Cancer Index Composite [EPIC]), urinary symptoms (International Prostate Symptom Score [IPSS]), erectile function (International Index of Erectile Function [IIEF]) and toxicity (Common Terminology Criteria for Adverse Events [CTCAE], version 3.0) were monitored prospectively. Univariate and multivariate logistic regression analysis was used to investigate associations between HRQOL/toxicity and baseline covariates. RESULTS: The median follow-up time was 5.2 years. The change in the median EPIC scores from baseline to year 5 in the urinary domain was from 91 to 85 (P = 0.0028), in the bowel domain was from 98 to 96 (P = 0.03), in the sexual domain was from 63 to 35 (P < 0.0001) and the hormonal domain remained unchanged at 95 (P = 0.93). Fifty-nine per cent and 46% of the patients with normal erectile function at baseline remained potent at year 1 and year 5, respectively. Late genitourinary toxicity grade 1, 2 and ≥3 occurred in 29, 59 and 4% of patients, respectively. The rates of late gastrointestinal toxicity grade 1, 2 and ≥3 were documented as 45, 19 and 0%, respectively. On multivariate logistic regression analysis, patients with larger prostates were more likely to develop a urinary late toxicity grade ≥2 (P = 0.01). The dose to 10% of the urethra was the only factor associated with a decline in the EPIC urinary domain score (P = 0.012). Prostate volume >43 ml was associated with higher late genitourinary toxicity grade ≥2. CONCLUSIONS: Single 15 Gy HDR brachytherapy with EBRT has a low rate of late genitourinary and gastrointestinal toxicities. Late urinary morbidity may be minimised by limiting the dose to the urethra, particularly for patients with larger prostates.
Asunto(s)
Braquiterapia/efectos adversos , Neoplasias de la Próstata/radioterapia , Calidad de Vida/psicología , Traumatismos por Radiación/etiología , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias de la Próstata/complicaciones , Hipofraccionamiento de la Dosis de Radiación , Dosificación RadioterapéuticaRESUMEN
PURPOSE OF THE STUDY: Pacemakers are currently identified as a contraindication for the use of magnetic growth rods (MGRs). This arises from concern that magnetic fields generated by the MGR external remote controller (ERC) during lengthening procedures may induce pacemaker dysfunction. We investigated (1) whether MGR lengthening affects pacemaker function, and (2) if the magnetic field of a pacemaker affects MGR lengthening. METHODS: MGRs were tested in conjunction with an magnetic resonance imaging-compatible pacemaker, which was connected to a virtual patient under continuous cardiac monitoring. To determine whether pacemaker function was affected during MGR lengthening, the electrocardiogram trace was monitored for arrhythmias, whereas an ERC was applied to lengthen the MGRs at varying distances from the pacemaker. To investigate if MGR lengthening was affected by the presence of a pacemaker, at the start and end of the experiment, the ability of the rods to fully elongate and shorten was tested to check for conservation of function. RESULTS: When the pacemaker was in normal mode, <16 cm away from the activated ERC during MGR lengthening, pacemaker function was affected by the ERC's magnetic forces. At this distance, prophylactically switching the pacemaker to tonic mode before lengthening prevented occurrence of inappropriate pacing discharges. No deleterious effect of the pacemaker's magnetic field on the MGR lengthening mechanism was identified. CONCLUSIONS: Magnetic resonance imaging-compatible pacemakers appear safe for concomitant use with MGRs, provided a pacemaker technician prophylactically switches the pacemaker to tonic function before outpatient lengthening procedures. CLINICAL RELEVANCE: This experiment was designed to provide the first safety information on MGR lengthening in children with pacemakers. Although currently a rare clinical scenario, with increasing use of MGRs, this clinical scenario may arise more frequently in the future.
Asunto(s)
Alargamiento Óseo/instrumentación , Imagen por Resonancia Magnética , Imanes/efectos adversos , Procedimientos Ortopédicos/instrumentación , Marcapaso Artificial , Escoliosis/cirugía , Alargamiento Óseo/métodos , Niño , Contraindicaciones , Electrocardiografía , Humanos , Fenómenos Magnéticos , Imagen por Resonancia Magnética/efectos adversos , Procedimientos Ortopédicos/métodosRESUMEN
Exact expressions of velocity, temperature and mass concentration have been calculated for free convective flow of fractional MHD viscous fluid over an oscillating plate. Expressions of velocity have been obtained both for sine and cosine oscillations of plate. Corresponding fractional differential equations have been solved by using Laplace transform and inverse Laplace transform. The expression of temperature and mass concentration have been presented in the form of Fox-H function and in the form of general Wright function, respectively and velocity is presented in the form of integral solutions using Generalized function. Some limiting cases of fluid and fractional parameters have been discussed to retrieve some solutions present in literature. The influence of thermal radiation, mass diffusion and fractional parameters on fluid flow has been analyzed through graphical illustrations.
RESUMEN
Intrinsically disordered proteins and intrinsically disordered regions (IDRs) are ubiquitous in the eukaryotic proteome. The description and understanding of their conformational properties require the development of new experimental, computational, and theoretical approaches. Here, we use nuclear spin relaxation to investigate the distribution of timescales of motions in an IDR from picoseconds to nanoseconds. Nitrogen-15 relaxation rates have been measured at five magnetic fields, ranging from 9.4 to 23.5 T (400-1000 MHz for protons). This exceptional wealth of data allowed us to map the spectral density function for the motions of backbone NH pairs in the partially disordered transcription factor Engrailed at 11 different frequencies. We introduce an approach called interpretation of motions by a projection onto an array of correlation times (IMPACT), which focuses on an array of six correlation times with intervals that are equidistant on a logarithmic scale between 21 ps and 21 ns. The distribution of motions in Engrailed varies smoothly along the protein sequence and is multimodal for most residues, with a prevalence of motions around 1 ns in the IDR. We show that IMPACT often provides better quantitative agreement with experimental data than conventional model-free or extended model-free analyses with two or three correlation times. We introduce a graphical representation that offers a convenient platform for a qualitative discussion of dynamics. Even when relaxation data are only acquired at three magnetic fields that are readily accessible, the IMPACT analysis gives a satisfactory characterization of spectral density functions, thus opening the way to a broad use of this approach.
Asunto(s)
Proteínas Intrínsecamente Desordenadas/química , Proteínas Intrínsecamente Desordenadas/metabolismo , Movimiento , Resonancia Magnética Nuclear Biomolecular , Cinética , Estructura Secundaria de ProteínaRESUMEN
A selective isotope labeling scheme based on the utilization of [2-(13)C]-glycerol as the carbon source during protein overexpression has been evaluated for the measurement of excited state (13)Cα chemical shifts using Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersion (RD) experiments. As expected, the fractional incorporation of label at the Cα positions is increased two-fold relative to labeling schemes based on [2-(13)C]-glucose, effectively doubling the sensitivity of NMR experiments. Applications to a binding reaction involving an SH3 domain from the protein Abp1p and a peptide from the protein Ark1p establish that accurate excited state (13)Cα chemical shifts can be obtained from RD experiments, with errors on the order of 0.06 ppm for exchange rates ranging from 100 to 1000 s(-1), despite the small fraction of (13)Cα-(13)Cß spin-pairs that are present for many residue types. The labeling approach described here should thus be attractive for studies of exchanging systems using (13)Cα spin probes.
Asunto(s)
Isótopos de Carbono/metabolismo , Glicerol/metabolismo , Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas/química , Proteínas/metabolismo , Isótopos de Carbono/análisis , Isótopos de Carbono/química , Redes y Vías Metabólicas , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Hydrocephalus (HC) has a multifactorial and complex picture of pathophysiology due to aetiology, age at and duration since onset. We have previously identified distinctions in markers of cell death associated with different aetiologies. Here, we examined cerebrospinal fluid (CSF) from human HC neonates for cytokines to identify further distinguishing features of different aetiologies. METHODS: CSF was collected during routine lumbar puncture or ventricular tap from neonates with hydrocephalus, or with no neurological condition (normal controls). Total protein, Fas receptor, Fas ligand, stem cell factor (SCF), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), insulin growth factor-1 (IGF-1), tumour necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) were measured and compared between 8 unaffected and 28 HC neonatal CSF samples. RESULTS: Total protein was significantly (P < 0.05) raised in late-onset hydrocephalus (LOH). Fas receptor was raised (P < 0.05) in post-haemorrhagic hydrocephalus (PHH) and spina bifida with hydrocephalus (SB/HC), but no difference in Fas ligand was found. SCF was raised (P < 0.05) in SB/HC. HGF was found in all HC and was increased (P < 0.01) in PHH. Increased VEGF was found in PHH (P < 0.01) and SB/HC (P < 0.05). Variable levels of IL-6, TNF-α and IGF-1 were found in all HC groups compared with none in normal. CONCLUSIONS: LOH was unusual with significantly raised total protein indicating an inflammatory state. Increased Fas receptor, VEGF, IGF-1 and HGF suggest anti-apoptotic and repair mechanism activation. By contrast, elevated TNF-α and IL-6 indicate inflammatory processes in these neonatal brains. Taken with our previous study, these data indicate that different pathophysiology, inflammation and repair are occurring in HC of different aetiologies and that additional treatment strategies may benefit these infants in addition to fluid diversion.