Secondary Forest Age and Tropical Forest Biomass Estimation Using TM

The age of secondary forests in the Amazon will become more critical with respect to the estimation of biomass and carbon budgets as tropical forest conversion continues. Multitemporal Thematic Mapper data were used to develop land cover histories for a 33,000 Square kM area near Ariquemes, Rondonia over a 7 year period from 1989-1995. The age of the secondary forest, a surrogate for the amount of biomass (or carbon) stored above-ground, was found to be unimportant in terms of biomass budget error rates in a forested TM scene which had undergone a 20% conversion to nonforest/agricultural cover types. In such a situation, the 80% of the scene still covered by primary forest accounted for over 98% of the scene biomass. The difference between secondary forest biomass estimates developed with and without age information were inconsequential relative to the estimate of biomass for the entire scene. However, in futuristic scenarios where all of the primary forest has been converted to agriculture and secondary forest (55% and 42% respectively), the ability to age secondary forest becomes critical. Depending on biomass accumulation rate assumptions, scene biomass budget errors on the order of -10% to +30% are likely if the age of the secondary forests are not taken into account. Single-date TM imagery cannot be used to accurately age secondary forests into single-year classes. A neural network utilizing TM band 2 and three TM spectral-texture measures (bands 3 and 5) predicted secondary forest age over a range of 0-7 years with an RMSE of 1.59 years and an R(Squared) (sub actual vs predicted) = 0.37. A proposal is made, based on a literature review, to use satellite imagery to identify general secondary forest age groups which, within group, exhibit relatively constant biomass accumulation rates

QT Interval Prolongation and Torsade De Pointes in Patients with COVID-19 treated with Hydroxychloroquine/Azithromycin

Background: There is no known effective therapy for patients with COVID-19. Initial reports suggesting the potential benefit of Hydroxychloroquine/Azithromycin (HY/AZ) have resulted in massive adoption of this combination worldwide. However, while the true efficacy of this regimen is unknown, initial reports have raised concerns regarding the potential risk of QT prolongation and induction of torsade de pointes (TdP). Objective: to assess the change in QTc interval and arrhythmic events in patients with COVID-19 treated with HY/AZ METHODS: This is a retrospective study of 251 patients from two centers, diagnosed with COVID-19 and treated with HY/AZ. We reviewed ECG tracings from baseline and until 3 days after completion of therapy to determine the progression of QTc and incidence of arrhythmia and mortality. Results: QTc prolonged in parallel with increasing drug exposure and incompletely shortened after its completion. Extreme new QTc prolongation to > 500 ms, a known marker of high risk for TdP had developed in 23% of patients. One patient developed polymorphic ventricular tachycardia (VT) suspected as TdP, requiring emergent cardioversion. Seven patients required premature termination of therapy. The baseline QTc of patients exhibiting extreme QTc prolongation was normal. Conclusion: The combination of HY/AZ significantly prolongs the QTc in patients with COVID-19. This prolongation may be responsible for life threating arrhythmia in the form of TdP. This risk mandates careful consideration of HY/AZ therapy in lights of its unproven efficacy. Strict QTc monitoring should be performed if the regimen is given

PLoS One

Inertial measurement units (IMUs) have been increasingly popular in rehabilitation research. However, despite their accessibility and potential advantages, their uptake and acceptance by health professionals remain a big challenge. The development of an IMU-based clinical tool must bring together engineers, researchers and clinicians. This study is part of a developmental process with the investigation of clinicians’ perspectives about IMUs. Clinicians from four rehabilitation centers were invited to a 30-minute presentation on IMUs. Then, two one-hour focus groups were conducted with volunteer clinicians in each rehabilitation center on: 1) IMUs and their clinical usefulness, and 2) IMUs data analysis and visualization interface. Fifteen clinicians took part in the first focus groups. They expressed their thoughts on: 1) categories of variables that would be useful to measure with IMUs in clinical practice, and 2) desired characteristics of the IMUs. Twenty-three clinicians participated to the second focus groups, discussing: 1) functionalities, 2) display options, 3) clinical data reported and associated information, and 4) data collection duration. Potential influence of IMUs on clinical practice and added value were discussed in both focus groups. Clinicians expressed positive opinions about the use of IMUs, but their expectations were high before considering using IMUs in their practice

T-lymphocyte subsets in liver tissues of patients with primary biliary cirrhosis (PBC), patients with primary sclerosing cholangitis (PSC), and normal controls

T lymphocytes infiltrating hepatic tissues were typed and enumerated in liver biopsies of patients with primary biliary cirrhosis (PBC), patients with primary sclerosing cholangitis (PSC), and normal controls using monoclonal antibodies and the avidin-biotin-immunoperoxidase technique. The peripheral blood mononuclear cells were studied also by flow cytometry. In PBC, T lymphocytes were decreased (P<0.001) in the blood [absolute number was 426±200 (SE) vs 1351±416 in 15 controls], as was the helper/suppressor (T4/T8) ratio (1.0±0.1 vs normal 2.3±0.3). T lymphocytes were the most numerous mononuclear cells infiltrating portal areas of PBC livers: 749±93/5 high-power fields (HPF) in PBC vs 98±15/5 HPF (P<0.01) in controls. The T4/T8 ratios varied from 0.9 to 2.3 (mean, 1.8±0.1) in the portal triads (normal mean, 1.6±0.1), with the T4+ cells accounting for more than 75% of infiltrating T cells. In contrast, the mean T4/T8 ratio in portal triads of PSC was reduced (1.0±0.3) due to a significant increase (P<0.001) in the number of T8+ cells. The T cells around and in the walls of bile ducts in PBC were mostly T8+, and the T4/T8 ratio was 0.8±0.2. No T8+ cells were seen in this location in PSC and normal livers. Few mononuclear cells were present in hepatic lobules. Subtyping of T lymphocytes in liver tissues of patients with PBC and PSC may be helpful in the differential pathologic diagnosis. In patients with advanced PBC, a decrease in T4+ cells in the blood appeared to be accompanied by their accumulation in the portal triads. In contrast, T8+ cells accumulated preferentially around bile ducts. © 1984 Plenum Publishing Corporation

Ozone observations and a model of marine boundary layer photochemistry during SAGA 3

A major purpose of the third joint Soviet‐American Gases and Aerosols (SAGA 3) oceanographic cruise was to examine remote tropical marine O3 and photochemical cycles in detail. On leg 1, which took place between Hilo, Hawaii, and Pago‐Pago, American Samoa, in February and March 1990, shipboard measurements were made of O3, CO, CH4, nonmethane hydrocarbons (NMHC), NO, dimethyl sulfide (DMS), H2S, H2O2, organic peroxides, and total column O3. Postcruise analysis was performed for alkyl nitrates and a second set of nonmethane hydrocarbons. A latitudinal gradient in O3 was observed on SAGA 3, with O3 north of the intertropical convergence zone (ITCZ) at 15–20 parts per billion by volume (ppbv) and less than 12 ppbv south of the ITCZ but never ≤3 ppbv as observed on some previous equatorial Pacific cruises (Piotrowicz et al., 1986; Johnson et al., 1990). Total column O3 (230–250 Dobson units (DU)) measured from the Akademik Korolev was within 8% of the corresponding total ozone mapping spectrometer (TOMS) satellite observations and confirmed the equatorial Pacific as a low O3 region. In terms of number of constituents measured, SAGA 3 may be the most photochemically complete at‐sea experiment to date. A one‐dimensional photochemical model gives a self‐consistent picture of O3‐NO‐CO‐hydrocarbon interactions taking place during SAGA 3. At typical equatorial conditions, mean O3 is 10 ppbv with a 10–15% diurnal variation and maximum near sunrise. Measurements of O3, CO, CH4, NMHC, and H2O constrain model‐calculated OH to 9 × 105 cm−3 for 10 ppbv O3 at the equator. For DMS (300–400 parts per trillion by volume (pptv)) this OH abundance requires a sea‐to‐air flux of 6–8 × 109 cm−2 s−1, which is within the uncertainty range of the flux deduced from SAGA 3 measurements of DMS in seawater (Bates et al., this issue). The concentrations of alkyl nitrates on SAGA 3 (5–15 pptv total alkyl nitrates) were up to 6 times higher than expected from currently accepted kinetics, suggesting a largely continental source for these species. However, maxima in isopropyl nitrate and bromoform near the equator (Atlas et al., this issue) as well as for nitric oxide (Torres and Thompson, this issue) may signify photochemical and biological sources of these species

Meta-Analysis for Genome-Wide Association Study Identifies Multiple Variants at the BIN1 Locus Associated with Late-Onset Alzheimer's Disease

Recent GWAS studies focused on uncovering novel genetic loci related to AD have revealed associations with variants near CLU, CR1, PICALM and BIN1. In this study, we conducted a genome-wide association study in an independent set of 1034 cases and 1186 controls using the Illumina genotyping platforms. By coupling our data with available GWAS datasets from the ADNI and GenADA, we replicated the original associations in both PICALM (rs3851179) and CR1 (rs3818361). The PICALM variant seems to be non-significant after we adjusted for APOE e4 status. We further tested our top markers in 751 independent cases and 751 matched controls. Besides the markers close to the APOE locus, a marker (rs12989701) upstream of BIN1 locus was replicated and the combined analysis reached genome-wide significance level (p = 5E-08). We combined our data with the published Harold et al. study and meta-analysis with all available 6521 cases and 10360 controls at the BIN1 locus revealed two significant variants (rs12989701, p = 1.32E-10 and rs744373, p = 3.16E-10) in limited linkage disequilibrium (r2 = 0.05) with each other. The independent contribution of both SNPs was supported by haplotype conditional analysis. We also conducted multivariate analysis in canonical pathways and identified a consistent signal in the downstream pathways targeted by Gleevec (P = 0.004 in Pfizer; P = 0.028 in ADNI and P = 0.04 in GenADA). We further tested variants in CLU, PICALM, BIN1 and CR1 for association with disease progression in 597 AD patients where longitudinal cognitive measures are sufficient. Both the PICALM and CLU variants showed nominal significant association with cognitive decline as measured by change in Clinical Dementia Rating-sum of boxes (CDR-SB) score from the baseline but did not pass multiple-test correction. Future experiments will help us better understand potential roles of these genetic loci in AD pathology

The expression of monocarboxylate transporters in thyroid carcinoma can be associated with the morphological features of BRAF (V600E) mutation

BRAF (V600E) mutation, usually performed by DNA techniques, is one of the most common diagnostic markers in papillary thyroid carcinoma. Few papers have demonstrated that plump cells (eosinophilic cytoplasms and papillary thyroid carcinoma nuclei) and peculiar sickle-shaped nuclei represent morphological features of BRAF (V600E) on papillary thyroid carcinomas. These features seem to be linked to glycolytic phenotype whereby monocarboxylate transporters 1-4 are hypothesized to have a dominant role as lactate transporters. We investigated the association between these morphological features and monocarboxylate transporters 1 and 4 in 48 cyto-histological samples diagnosed as "positive for malignancy-favoring papillary thyroid carcinoma". These cases were processed with liquid-based cytology and underwent BRAF (V600E) mutational analysis (pyrosequencing) on liquid-based cytology and monocarboxylate transporters immunostaining on histology. The expression of monocarboxylate transporter 1, monocarboxylate transporter 4, glucose trasporter-1 and carbonic anhidrase were scored semi-quantitatively with expression from 0 to 3+ (strong positivity). The 33 mutated and 15 wild type cases showed 100 % cyto-histological concordance. The cytological evaluation revealed plump cells and sickle nuclear shape in 100 % mutated cases. Monocarboxylate transporter 1 yielded 76 % positivity in the mutated cases especially in both the plump cells and sickle-shaped nuclei, whereas the wild types showed 13.3 % positive monocarboxylate transporter 1 (p = 0.00013). Monocarboxylate transporter 4 resulted in 100 % positivity in mutated and 40 % in wild types (p 0.05). This is the first report analyzing the association between monocarboxylate transporter expression and the morphological features of BRAF (V600E) mutated papillary thyroid carcinomas suggesting the possible involvement of lactate in the morphological features.info:eu-repo/semantics/publishedVersio