1,677 research outputs found
Plasma cell free next-generation sequencing detects an unusual pneumonia pathogen in an immunocompetent adolescent with acute respiratory distress syndrome
This case details a rapid diagnosis of legionella pneumonia causing severe acute respiratory distress syndrome (ARDS) in an otherwise healthy adolescent through plasma microbial cell-free DNA next generation sequencing (mcfDNA-NGS). Diagnosis by mcfDNA-NGS of this unexpected pathogen led to narrowing of antimicrobials and the addition of glucocorticoids as adjunctive therapy for ARDS
The Transcription Factor NFAT5 Is Required for Cyclin Expression and Cell Cycle Progression in Cells Exposed to Hypertonic Stress
Background: Hypertonicity can perturb cellular functions, induce DNA damage-like responses and inhibit proliferation. The transcription factor NFAT5 induces osmoprotective gene products that allow cells to adapt to sustained hypertonic conditions. Although it is known that NFAT5-deficient lymphocytes and renal medullary cells have reduced proliferative capacity and viability under hypertonic stress, less is understood about the contribution of this factor to DNA damage responses and cell cycle regulation. Methodology/Principal Findings: We have generated conditional knockout mice to obtain NFAT5ā/ā T lymphocytes, which we used as a model of proliferating cells to study NFAT5-dependent responses. We show that hypertonicity triggered an early, NFAT5-independent, genotoxic stress-like response with induction of p53, p21 and GADD45, downregulation of cyclins, and cell cycle arrest. This was followed by an NFAT5-dependent adaptive phase in wild-type cells, which induced an osmoprotective gene expression program, downregulated stress markers, resumed cyclin expression and proliferation, and displayed enhanced NFAT5 transcriptional activity in S and G2/M. In contrast, NFAT5ā/ā cells failed to induce osmoprotective genes and exhibited poorer viability. Although surviving NFAT5ā/ā cells downregulated genotoxic stress markers, they underwent cell cycle arrest in G1/S and G2/M, which was associated with reduced expression of cyclins E1, A2 and B1. We also show that pathologic hypertonicity levels, as occurring in plasma of patients and animal models of osmoregulatory disorders, inhibited the induction of cyclins and aurora B kinase in response to T cell receptor stimulation in fresh NFAT5ā/ā lymphocytes. Conclusions/Significance: We conclude that NFAT5 facilitates cell proliferation under hypertonic conditions by inducing an osmoadaptive response that enables cells to express fundamental regulators needed for cell cycle progression.Molecular and Cellular Biolog
The Validity and Reliability of the Garmin Instinct in Measuring Heart Rate, Energy Expenditure, and Steps During Skipping
As the use of wearable technology to monitor physical activity increases, assessment of the validity and reliability of these devices are needed. A popular device brand is Garmin. Although not a common physical activity, skipping can be included in dynamic warm-ups. PURPOSE: Therefore, the purpose of this study was to determine the validity and reliability of the Garmin Instinct in measuring caloric energy expenditure (EE), average heart rate (HR), and steps while skipping. METHODS: Ten participants (5 female, age: 27Ā±9 years) skipped at a self-selected pace for five minutes. During that time, HR, EE, and steps were measured by the Polar H10, Cosmed K5, and manual counting, respectively. Two Garmin Instincts simultaneously tracked all three variables. A step was defined as any time the foot leaves and hits the ground (stride x 4). Data was input into Google Sheets and summary statistics, t-test with Bonferonni corrections, and mean absolute percentage error (MAPE) were calculated. Additional validity and reliability tests were run in jamovi, including Linās concordance correlation coefficient (CCC), TOST tests, Bland-Altman bias, coefficient of variation (CV), and intraclass correlation coefficient (ICC). The pre-established validity criteria are as follows: CCC \u3e 0.7 and MAPE \u3c 10%. The pre-established reliability criteria are as follows: CV \u3c 10% and ICC \u3e 0.7. RESULTS: The Garmin Instinct had a MAPE of 19.2%, 28.5%, and 53.2% for HR, EE, and steps, respectively. It had a CCC of .06, .21, and .01 for HR, EE, and steps, respectively. The 2-tailed paired t-tests with corrections for multiple comparisons was significant for HR and steps. The TOST tests were violated for all 3 measurements (HR, EE, and steps). Bland-Altman analysis produced a bias estimate of 34.0, 0.6, and 1100 for HR, EE, and steps, respectively. The Garmin produced a CV of 11.2%, 14.8%, and 6.6% for HR, EE, and steps, respectively. It produced an ICC of .51, .64, and .81 for HR, EE, and steps, respectively. CONCLUSION: The Garmin Instinct did not meet the pre-established validity criteria for any measure (HR, EE, or steps). However, it did meet the pre-established reliability criteria for steps but not for HR or EE. Therefore, the Garmin Instinct cannot be expected to produce accurate estimates of HR, EE, or steps during skipping
A High Resolution Radio Survey of Class I Protostars
We report the results of a survey of low mass Class I protostars in the cm
continuum. In the initial survey, seven sources in the Taurus star formation
were observed with the VLA at 0``.25 resolution. All seven sources drive CO
outflows and display Herbig-Haro flows in the optical or near infrared
wavebands. 4/7 sources were detected, two of which are new discoveries in
systems of very low luminosity, one being the lowest luminosity system detected
to date in the cm continuum. Notably, three sources were not detected to a
3-sigma limit of 0.10 mJy/beam, which indicates that significant cm continuum
emission is not a universal feature of Class I systems with outflow activity.
Subsequent observations of HH30, a more evolved Class II system, found no
emission to a 3-sigma limit of 0.03 mJy/beam. After comparison with near
infrared data, we suggest that the discriminating feature of the detected
systems is a relatively high ionisation fraction in the stellar wind. Temporal
variability of the outflow may also play a role. The one relatively bright
source, IRAS 04016+2610 (L1489 IRS), is clearly resolved on a 0``.4 scale at 2
cm and 3.5 cm. Follow-up imaging with MERLIN did not detect this source with a
0``.04 beam, indicating that the radio emission is generated in a region with a
radius of about 25 au, which is broadly similar to the radius of the bipolar
cavities inferred from models of near infrared data. Interpretation of this
system is complicated by the existence of a quadrupolar outflow, which we
originally detected through polarimetric imaging. We present a near infrared H2
image in which a bow shock in the secondary outflow is clearly seen. This
complicated structure may have been caused by a gravitational interaction
between two protostars.Comment: Accepted by MNRAS. 16 pages, 5 figures, 9 postscript files, 1 Latex
fil
Recombinant human erythropoietin promotes the acquisition of a malignant phenotype in head and neck squamous cell carcinoma cell lines in vitro
<p>Abstract</p> <p>Background</p> <p>Recent studies indicate an increase in tumor progression and recurrence in head and neck squamous cell carcinomas (HNSCC) of cancer patients taking recombinant human erythropoietin (rhEpo) for anemia. This study was undertaken to investigate the potential role of rhEpo in invasion, proliferation, and cisplatin-induced cell death in HNSCC cell lines.</p> <p>Methods</p> <p>The following experiments were performed with two HNSCC cell lines, UMSCC-10B and UMSCC-22B. Presence of EpoR in both cell lines was determined by western blot and quantitative PCR. Colorimetric MTS assays and clonogenic assays were used to study the effect of rhEpo at pharmacologically relevant doses on cell proliferation. Matrigel invasion assays were performed in order to determine effects of exogenous rhEpo on invasive abilities. Clonogenic assays were also used to study potential cytoprotective effects of rhEpo against cisplatin. Immunoblotting was done to analyze the effect of rhEpo on Akt phosphorylation. Finally, MTS and TUNEL assays were performed to test our hypothesis that Akt activation by PI3K was involved in rhEpo-mediated cisplatin resistance.</p> <p>Results</p> <p>HNSCC cell lines were shown to express Epo receptor (EpoR). RhEpo increased invasion 1.8-fold in UMSCC-10B and 2.6-fold in UMSCC-22B compared to control. RhEpo at 10 U/ml increased cell proliferation by 41% and 53% in UMSCC-10B and UMSCC-22B, respectively, and colony formation by 1.5-fold and 1.8-fold. UMSCC-10B treated with cisplatin and exposed to rhEpo at 1 and 10 U/ml resulted in a 1.7-fold and 3.0-fold increase in colony number compared to control, respectively. UMSCC-22B treated with cisplatin and rhEpo at 1 or 10 U/ml resulted in ~2.5-fold increase in colony number. A TUNEL assay demonstrated a 30.5% and 76.5% increase in survival in UMSCC-10B and UMSCC-22B cells, respectively, in cisplatin and rhEpo-treated cells compared to cisplatin alone. MTS assay showed similar cytoprotective effects. Western blot revealed increased phosphorylation of Akt upon exposure of HNSCC cell lines to rhEpo. MTS assay and TUNEL analyses implicate Akt as a likely contributor to regulation of rhEpo-mediated cytoprotection.</p> <p>Conclusions</p> <p>The results demonstrate that, in HNSCC cells expressing functional EpoR, rhEpo promotes invasion, cell proliferation, and induces resistance to cisplatin, which may contribute to tumor progression.</p
Determining Validity and Reliability of Caloric Expenditure Recorded by Wearable Technology While Walking and Running
With growing interest in tracking exercise progress, wearable technology is increasingly popular. While heart rate and step count are typically accurate for consumer-available devices, research from our laboratory indicates that caloric expenditure is not. PURPOSE: The current investigation aimed to evaluate the validity and reliability of caloric expenditure in multiple wearable devices during a self-paced walk and run. METHODS: Ten participants were tested (5F, 5M, age = 26.9Ā± 9.43 years, body mass = 72.64Ā± 7.73 kg, height = 168.66Ā± 9.37 cm). Participants were asked to wear 5 devices: 2 Garmin Instinct watches (one on each wrist), 2 Polar Vantage M2 watches, and a K5 portable metabolic analysis system (criterion measure). Data was collected from all devices while participants completed a 5-minute self-paced walk, followed by a 5-minute rest period, then a 5-minute self-paced run. Validity was evaluated using the mean absolute percent error (MAPE) with a threshold of below 10 percent and Linās Concordance Correlation Coefficient (CCC) with significance above 0.7. Reliability was evaluated using the Intraclass Correlation Coefficient (ICC) and Coefficient of Variation (CV). RESULTS: For validity, neither device met the predetermined threshold for MAPE or CCC (see results table for reference). For reliability, only the Polar device during the running condition returned consistent results for both measures. CONCLUSION: These results indicate neither brand of watch produced valid energy expenditure estimates. Reliability was also poor. This poses a challenge to people relying on wearable devices to keep an accurate, consistent log of caloric expenditure. Our research does not indicate that technology is keeping up with how rapidly it is being developed and sold to the public
The Validity of Bicep Located Heart Rate Monitors During Running
Running is a popular sport with 621 million people participating worldwide. Heart rate (HR) is a way to determine intensity but many people do not want to wear a HR strap around their chest because it is uncomfortable and can cause chaffing. An alternative location for determining HR could be the biceps but the validity of such devices need to be determined. PURPOSE: To determine the validity of the Polar OH 1 and Polar Verity biceps devices during self-paced running. METHODS: Wearing Polar OH1, Polar Verity, and Polar H10 (criterion) 5 female and 5 male participants were asked to perform running for 5 minutes up and down a 100 ft hallway. The average HR and maximal HR over the run was recorded in beats per minute (bpm). Validity was determined using mean absolute percent error (MAPE) and Lin\u27s concordance (CCC), with a threshold of less than 10% and greater than 0.70 respectively. The threshold for both was required to be met to be considered valid. RESULTS: Average HR returned from the devices was: Polar H10 = 154.6 (16.3) [mean (standard deviation)], Polar OH1 = 152.0 (16.2), and Polar Verity = 151.1 (16.5) bpm. The average HR MAPE for the Polar OH1 and the Polar Verity was 12.2% and 12.6%, respectively, and the CCC for each device was 0.94 and 0.90. Maximal HR returned from the devices was: Polar H10 = 174.2 (18.1), Polar OH1 = 171.8 (18.8), and Polar Verity = 167.2 (35.1) bpm. The maximal HR MAPE for the Polar OH1 and the Polar Verity was 1.3% and 4.2%, respectively. The CCC for each device was 0.93 and 0.43, respectively. CONCLUSION: We evaluated whether HR monitors located on the biceps could return accurate measures. Neither device met both thresholds when average HR was considered. Because the Polar OH 1 satisfied both thresholds for maximal HR, we conclude it to be the more accurate device for use during running. These results should be used with caution until further improvements in biceps located devices can be made to return valid measures for both average and maximal heart rate
Assay development and inhibition of the Mt-DprE2 essential reductase from Mycobacterium tuberculosis
Candidate Sequence Variants and Fetal Hemoglobin in Children with Sickle Cell Disease Treated with Hydroxyurea
Fetal hemoglobin level is a heritable complex trait that strongly correlates with the clinical severity of sickle cell disease. Only few genetic loci have been identified as robustly associated with fetal hemoglobin in patients with sickle cell disease, primarily adults. The sole approved pharmacologic therapy for this disease is hydroxyurea, with effects largely attributable to induction of fetal hemoglobin. In a multi-site observational analysis of children with sickle cell disease, candidate single nucleotide polymorphisms associated with baseline fetal hemoglobin levels in adult sickle cell disease were examined in children at baseline and induced by hydroxyurea therapy. For baseline levels, single marker analysis demonstrated significant association with BCL11A and the beta and epsilon globin loci (HBB and HBE, respectively), with an additive attributable variance from these loci of 23%. Among a subset of children on hydroxyurea, baseline fetal hemoglobin levels explained 33% of the variance in induced levels. The variant in HBE accounted for an additional 13% of the variance in induced levels, while variants in the HBB and BCL11A loci did not contribute beyond baseline levels. These findings clarify the overlap between baseline and hydroxyurea-induced fetal hemoglobin levels in pediatric disease. Studies assessing influences of specific sequence variants in these and other genetic loci in larger populations and in unusual hydroxyurea responders are needed to further understand the maintenance and therapeutic induction of fetal hemoglobin in pediatric sickle cell disease
Modafinilās effects on cognition and sleep quality in affectively-stable patients with bipolar disorder: a pilot study
IntroductionDespite advances in the treatment of bipolar disorder (BD), most patients do not achieve complete inter-episode recovery and functional disability is common. During periods of relative remission, many patients continue to experience neurocognitive dysfunction, reduced daytime activity levels, and sleep disturbances. This 8-week, randomized, placebo-controlled pilot study evaluated the feasibility, safety and preliminary efficacy of the wake-promoting drug, modafinil (ProvigilĀ®), on neurocognitive functioning, daytime sleepiness, and sleep quality in affectively-stable BD patients.MethodsTwelve individuals with affectively-stable BD were recruited and randomized to a flexible dose of modafinil (100 to 200āmg/day) or placebo, adjunctive to a therapeutic dose of a mood stabilizer. Weekly in-person visits tracked sleep quality and daytime sleepiness as well as side effects and mood symptoms. Neurocognitive functioning was assessed at baseline, week 4, and week 8.ResultsNo serious adverse events were reported. Newly emergent side effects in the modafinil group included heart palpitations, itching, fatigue, and decreased energy. Two patients discontinued modafinil owing to side effects and one of these patients withdrew from the study. One patient discontinued placebo and was withdrawn from the study. Preliminary evaluations of clinical efficacy showed a marginally significant interaction between treatment group and time in two cognitive domains (speed of processing and verbal learning), indicating greater improvement in the modafinil group versus placebo. Additionally, there was a marginally significant effect of treatment group on daytime sleepiness, suggesting lower daytime sleepiness in the modafinil group versus placebo. Counterintuitively, we found a significant treatment group by time interaction effect on sleep quality, suggesting greater improvement in sleep quality in the placebo group versus the modafinil group.DiscussionResults suggest that modafinil is a relatively safe medication for affectively-stable BD patients when given with adjunctive mood stabilizers. Results are suggestive of cognitive benefit and improved daytime sleepiness, but worse sleep quality in those patients prescribed modafinil. A fully powered clinical trial is warranted with specific attention to the characteristics of patients who are most likely to benefit from treatment with modafinil and other methodological lessons learned from this pilot.Clinical trial registrationClinicalTrials.gov, identifier NCT01965925
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