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Remotely-sensed vegetation greening along a restoration gradient of a tropical forest...
Anu Valtonen
Eveliina Korkiatupa

Anu Valtonen

and 4 more

April 09, 2021
Restoration has now emerged as a global priority, with international initiatives such as the “UN Decade on Ecosystem Restoration (2021-2030)”. To fulfil the large-scale global restoration ambitions, an essential step is the monitoring of vegetation recovery after restoration interventions. The aim of this study was to evaluate the utility of remotely-sensed vegetation indices, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI), to monitor the rate of forest regeneration across a tropical forest restoration project area in Kibale National Park, Uganda. As a result, we observed non-linear patterns in NDVI and EVI across the first 25 years of recovery. Both NDVI and EVI increase for the first 10 years of forest regeneration. This “greening” phase could be used as the indicator of successful onset of forest recovery. In particular, the decline of elephant grass, which suppresses the natural regeneration of trees in our area, can be detected as an increase in NDVI. Primary forests differed from the 25-year-old regenerating forests based on the unique combination of low mean and low seasonal variation in EVI. Our results, therefore, suggest that the long-term success of forest restoration could be monitored by evaluating how closely the combination of mean, and degree of seasonal variation in EVI, resembles that observed in the primary forest.
Evaluation and Comparison of the GWR Merged Precipitation and Multi-Source Weighted-E...
Jing Zhao
Yuan Qiqi

Jing Zhao

and 4 more

April 09, 2021
Accurate estimation of precipitation in both space and time is essential for hydrological research. We compared multi-source weighted ensemble precipitation (MSWEP) with multi-source fused satellite precipitation (CHIRPS) based on high-density rain gauge precipitation observations in the Taihu Lake basin. We proposed a new merge precipitation algorithm GWRMP based on the geographically weighted regression (GWR) method. GWRMP corrects the bias of MSWEP by using high-density rain gauge precipitation to address the common problem of daily precipitation underestimation in MSWEP. The large-scale spatial coverage of the water surface in this region leads to the uneven distribution of rain gauges on the lake. There are differences in the descriptive ability of the three spatial precipitation types, MSWEP, GWRMP, and IDW, for spatial and temporal precipitation information in the Taihu Lake basin. A comparison shows that GWRMP has a significant advantage in obtaining the spatial and temporal variability of precipitation in areas with complex topographic conditions. GWRMP compensates the problem of underestimation of precipitation by MSWEP (10% to 25%), and avoids the risk of the high dependence of IDW on rain gauges, and improves the accuracy of spatial and temporal precipitation in large lake areas with sparse distribution of rain gauges (Pbias limited to 10%). GWRMP improved the estimation for different rainfall intensities in the Taihu Lake basin, especially in the mid-level rainfall and above precipitation frequencies. Compared with IDW and MSWEP, GWRMP is more suitable for intense precipitation monitoring and storm flood frequency study in the basin. Therefore, GWRMP is a better choice for spatial and temporal estimation of precipitation in the Taihu Lake basin. The GWRMP algorithm can be applied to other regions with unevenly spaced high-density rain gauges.
Prediction of Cossus Linnaeus suitable growing area in China under Future Climate cha...
hua zhang
ming li

hua zhang

and 3 more

April 09, 2021
CossusLinnaeus is a kind of insect that causes great harm to forest trees in China, which has a great impact on the country’s agriculture and forestry, and seriously affects the stability of the ecosystem, so it is very important to predict its distribution and contain it. Most researchers use the MaxEnt model with default parameters to build models to predict the potential geographical distribution of species. Recent studies have found that in the case of default parameters, the prediction results of MaxEnt model are not only inaccurate, but also sometimes difficult to explain. In this paper, ENMeval packets are used to adjust the optimal feature combination parameters of MaxEnt model, and then the MaxEnt model with optimal parameters is used to predict the potential geographical distribution of CossusLinnaeus under present and future climatic conditions. The simulation results show that the simulation effect of the MaxEnt model is good (the area under the ROC curve (AUC = 0.914), Cossus Linnaeus is mainly distributed in Liaoning Province, Hebei Province, Shandong Province, Henan Province, Shaanxi Province, Shanxi Province, Ningxia and Gansu Province, etc., which is consistent with the actual distribution results. Under future climatic conditions, the area of Cossus Linnaeus high suitable growth area will rise up 26.7% to 87.4% compared with the current one. Climate change affects the potential distribution of Cossus Linnaeus, and the top four environmental variables with contribution rate are normalized vegetation index (NDVI,40.3%), annual mean temperature (Bio1,24.1%), coldest monthly minimum temperature (Bio6,12.4%) and diurnal range of mean temperature (Bio2,9%). Under the condition of future climate change, the center of gravity of Cossus Linnaeus will move to high latitudes. This study will provide theoretical support for the prevention and control of Cossus Linnaeus and tree protection in China.
Two sides of the same coin? How quality improvement can be used to augment program ev...
Allison Brown
Lawrence Grierson

Allison Brown

and 1 more

April 09, 2021
Health professions education is in constant pursuit of new ways of teaching and assessment in order to improve the training of healthcare professionals. Educators are often challenged with designing, implementing, and evaluating programs in the context of their professional practice, particularly those in response to dynamic and emerging social needs. This article explores the synergies and intersections of two approaches -- quality improvement and program evaluation -- and the potential utility of their combinations within our field to design, evaluate, and most importantly, improve educational programming. We argue that the inclusion of established quality improvement frameworks within program evaluation provides a proven mechanism for driving change, can optimize programming within the multi-contextual education systems, and, ultimately, that these two approaches are complementary to one another. These combinations hold great promise for optimizing programming in alignment with social missions, where it has been difficult for institutions worldwide to generate and capture evidence of social accountability.
Chromosome-scale assembly and whole-genome sequencing of 266 giant panda roundworms p...
Lei Han
Tian Lan

Lei Han

and 27 more

April 09, 2021
Helminth diseases have long been a threat to the health of humans and animals. Roundworms are important organisms for studying parasitic mechanisms, disease transmission and prevention. The study of parasites in the living fossil giant panda is of great significance for understanding the adaptation mechanism of roundworms to the host. Here, we report a high-quality chromosome-scale genome of Baylisascaris schroederi with a genome size of 262 Mb and 19,291 predicted protein-coding genes. We found a significant expansion of genes related to epidermal chitin synthesis and environmental information processing in roundworms genome. Furthermore, we demonstrated unique genes involved in essential amino acid metabolism in the B. schroederi genome, inferred to be essential for the adaptation to the giant panda-specific diet. In addition, under different deworming pressures, we found that four resistance-related genes (glc-1, nrf-6, bre-4 and ced-7) were under strong positive selection in captive population. Finally, 23 known drug targets and 47 potential target proteins were identified. The genome provides a unique reference for inferring the early evolution of roundworms and the mechanisms underlying adaptive. Population genetic analysis and drug prediction provide insights for revealing the impact of deworming history on population genetic structure and prevention.
A chromosome-anchored genome assembly for Lake Trout (Salvelinus namaycush)
Seth Smith
Eric Normandeau

Seth Smith

and 11 more

April 08, 2021
Here we present an annotated, chromosome-anchored, genome assembly for Lake Trout (Salvelinus namaycush) – a highly diverse salmonid species of notable conservation concern and an excellent model for research on adaptation and speciation. We leveraged Pacific Biosciences long-read sequencing, paired-end Illumina sequencing, proximity ligation (Hi-C), and a previously published linkage map to produce a highly contiguous assembly composed of 7,378 contigs (contig N50 = 1.8 mb) assigned to 4,120 scaffolds (scaffold N50 = 44.975 mb). 84.7% of the genome was assigned to 42 chromosome-sized scaffolds and 93.2% of Benchmarking Universal Single Copy Orthologs were recovered, putting this assembly on par with the best currently available salmonid genomes. Estimates of genome size based on k-mer frequency analysis were highly similar to the total size of the finished genome, suggesting that the entirety of the genome was recovered. A mitome assembly was also produced. Self-vs-self synteny analysis allowed us to identify homeologs resulting from the Salmonid specific autotetraploid event (Ss4R) and alignment with three other salmonid species allowed us to identify homologous chromosomes in other species. We also generated multiple resources useful for future genomic research on Lake Trout including a repeat library and a sex averaged recombination map. A novel RNA sequencing dataset was also used to produce a publicly available set of gene annotations using the National Center for Biotechnology Information Eukaryotic Genome Annotation Pipeline. Potential applications of these resources to population genetics and the conservation of native populations are discussed.
Model-based Design of Experiments for Polyether Production from Bio-based 1,3-Propane...
Anh-Duong Vo
Ali Shahmohammadi

Anh-Duong Vo

and 2 more

April 08, 2021
Sequential model-based design of experiments (MBDOE) is used to select operating conditions for new experiments in a batch-reactor that produces bio-based poly(trimethylene) ether glycol (PO3G). These Bayesian A-optimal experiments are designed to obtain improved estimates of the 70 fundamental-model parameter estimates, while accounting for the model structure and for data from eight previous industrial batch-reactor runs. Settings are selected for three decision variables: reactor temperature, initial catalyst level, and initial water concentration. If only one new experiment is conducted, it should be run at high temperature, with relatively high concentrations of catalyst and initial water. When two new runs are conducted, one should use an intermediate catalyst concentration. The effectiveness of the proposed MBDOE approach is tested using Monte-Carlo simulations, revealing that the selected experiments are superior compared to new experiments selected randomly from corners of the permissible design space.
EKG Findings Mimicking Pericarditis and STEMI in a patient with Ventricular Preexcita...
Ibraheem Rehman

Ibraheem Rehman

and 3 more

April 08, 2021
Wolff-Parkinson-White (WPW) syndrome is an electrical conduction abnormality of the heart in which atrial impulses are transmitted to the ventricle through an accessory pathway, leading to supraventricular tachycardia [1]. On EKG, WPW presents with shortened PR interval, widened QRS, and a characteristic delta wave. Here, we present the case of 44-year-old African American male with a history of preexcitation/WPW pattern and no known history of coronary artery disease who came to the hospital complaining of atypical chest pain. He had transient ST elevation in beats with delta waves, both in the ambulance and emergency room EKGs (Figure 1 and 2) . Five minutes later, a repeat EKG showed ST elevation along with PR depression mimicking pericarditis (Figure 4) . Cardiac enzymes remained normal. EKG stress test with myocardial perfusion imaging was negative for ischemia and echocardiogram was normal.
The role of melatonin in pregnancies complicated by placental insufficiency: a system...
Ilaria Fantasia
Sofia Bussolaro

Ilaria Fantasia

and 3 more

April 08, 2021
Background: Pregnancies complicated by placental insufficiency are characterised by increased oxidative stress. It has been suggested that melatonin has antioxidant properties and contributes to the maintenance of placental homeostasis. Objective: To systematically review the available literature about melatonin in pregnancies complicated by placental insufficiency, specifically preeclampsia and fetal growth restriction, exploring three different aspects: 1) maternal melatonin levels; 2) expression and activity of melatonin placental receptors; 3) effects of maternal melatonin administration. Search strategy: PubMed (Medline) and Scopus were searched until December 2020. Selection criteria: Published literature in English language describing the role of melatonin in pregnancies complicated by placental insufficiency, with a specific focus on preeclampsia and fetal growth restriction. Data collection and analysis: Identified studies were screened and assessed independently by two authors. Data were extracted and compiled in a qualitative evidence synthesis. Main results: Pregnancies complicated by placental insufficiency show a significant reduction in maternal systemic serum melatonin levels and a significant reduction in the expression of placental melatonin receptors. Melatonin administration in pregnancy seems safe and may reduce oxidative stress. Conclusion: The circadian pattern of melatonin secretion seems to be altered in pregnancies complicated by placental insufficiency. This is reflected by lower production of melatonin, with consequent lower systemic and placental concentrations, and lower expression of melatonin receptors, thus reducing the local release of the indole and its autocrine function. Funding: None Keywords: Melatonin, Preeclampsia, Fetal growth restriction, Placental insufficiency, Review.
How we approach coagulopathy with vascular anomalies.
Joana Mack
Shelley Crary

Joana Mack

and 1 more

April 08, 2021
Some vascular anomalies can present with challenging hematologic aberrations. Kaposiform hemangioendothelioma (KHE) may be complicated with Kasabach-Merritt phenomenon (KMP) and stagnant blood flow in slow flow malformations can promote activation and consumption of coagulation factors which results in bleeding and clotting known as localized intravascular coagulopathy (LIC). These patients can experience significant morbidity secondary to pain due to thrombosis and are at higher risk of hematologic complications during surgical procedures. No standard of care has been established to prevent or manage these complications. This review focuses on the management of coagulopathy in children and adults with vascular anomalies.
Systematic review of the effects of antimicrobial cycling on bacterial resistance rat...
Marianneta Chatzopoulou
Lucy Reynolds

Marianneta Chatzopoulou

and 1 more

April 08, 2021
Aim Antimicrobial resistance is an evolving phenomenon with alarming public health consequences. Antibiotic cycling is a widely known antimicrobial stewardship initiative which encompasses periodical shifts in empirical treatment protocols with the aim to limit selective pressures on bacterial populations. Nonetheless, mathematical models have challenged its presumable efficacy by favouring a higher heterogeneity in antibiotic administration. We present a review of the evidence regarding the actual impact of antimicrobial cycling on bacterial resistance control within hospitals. Methods A systematic literature review was conducted using the PubMed/MedLine, Embase, CINAHL Plus and Global Health databases. Results A systematic search process retrieved a sole randomised study, and so we broadened inclusion criteria to encompass quasi-experimental designs. Fifteen studies formed our dataset including seven prospective trials and eight before-and-after studies. Nine studies evaluated cycling versus a control group and produced conflicting results whilst three studies compared cycling with antibiotic mixing, with none of the strategies appearing superior. The rest evaluated resistance dynamics of each of the on-cycle antibiotics with contradictory findings. Research protocols differed in parameters such as the cycle length, the choice of antibiotics, the opportunity to de-escalate to narrow-spectrum agents and the measurement of indicators of collateral damage. This limited our ability to evaluate the replicability of findings and the overall policy effects. Conclusions Dearth of robust designs and standardised protocols limits our ability to reach safe conclusions. Nonetheless, in view of the available data we find no reason to believe that cycling should be expected to improve antibiotic resistance rates within hospitals.
COVID-19 in pediatric cancer: where are the brain tumors?
Rebecca Ronsley
Eric Bouffet

Rebecca Ronsley

and 1 more

April 08, 2021
Treatment of pediatric oncology patients generally results in significant immunosuppression and when the COVID-19 pandemic arose, there was concern among pediatric oncologists about the implications of this virus. We reviewed the literature and describe all pediatric oncology patients with COVID-19 reported worldwide. Within this review, it is striking that CNS tumors are reported at low numbers (27/466 pediatric oncology patients with COVID-19). This may be related to decreased inpatient care when compared to other pediatric cancers. Additional work is needed to understand the risk of infection in this population and gain insight into the effect on delivery of oncology care.
Treatment outcome of newly diagnosed multiple myeloma patients: A retrospective analy...
Chin Sum Cheong
Tengku Ahmad Hidayat Tengku K Aziz

Chin Sum Cheong

and 7 more

April 08, 2021
Multiple myeloma is the third most common hematologic malignancy in Malaysia. The introduction of novel agents over the past decades has improved patient outcome and survival substantially. The usage of novel agents can be financially taxing, and hence resources limit its use. This study aims to report on the real-world treatment outcome when resources are limited. This is a retrospective study on newly diagnosed multiple myeloma (NDMM) patients diagnosed between 1 January 2008 and 31 December 2018 in a single academic center. Patients demographic and type of treatment were included for analysis of progression free survival and overall survival. Ninety-eight NDMM patients with a median age of 63.5 (ranged from 38 to 87 years old) were included. Half of the total patients received bortezomib-containing regimens while 40.8% received thalidomide-containing regimens, and remaining 9.2% had other agents as induction. Forty-seven patients (48.0%) achieved very good partial response (VGPR) or complete remission (CR), while remaining 51 patients (52.0%) have achieved partial response (PR) at best during induction therapy. Bortezomib use was associated with significantly deeper (p=0.001) and more rapid response (p=0.005) compared to other agents. Five-year OS and PFS were 45.3% and 18.4%, respectively. Triplet regimen, best initial response and upfront ASCT were significantly associated with better PFS. In conclusion, deep response significantly affects PFS and OS in NDMM patients. Thus, one of the goals of treatment is to ensure earlier and deeper response by including bortezomib as part of triplet combination in upfront therapy, followed by ASCT for those who are fit. This is feasible in a resource limited country such as Malaysia, especially there is a cheaper generic formulation.
Goodness-of-fit Measures Based on the Mellin Transform for Beta Generalized Lifetime...
Josimar Vasconcelos
Renato Cintra

Josimar Vasconcelos

and 2 more

April 08, 2021
In recent years various probability models have been proposed for describing lifetime data. Increasing model flexibility is often sought as a means to better describe asymmetric and heavy tail distributions. Such extensions were pioneered by the beta-G family. However, efficient goodness-of-fit (GoF) measures for the beta-G distributions are sought. In this paper, we combine probability weighted moments (PWMs) and the Mellin transform (MT) in order to furnish new qualitative and quantitative GoF tools for model selection within the beta-G class. We derive PWMs for the Fr\’{e}chet and Kumaraswamy distributions; and we provide expressions for the MT, and for the log-cumulants (LC) of the beta-Weibull, beta-Fr\’{e}chet, beta-Kumaraswamy, and beta-log-logistic distributions. Subsequently, we construct LC diagrams and, based on the Hotelling’s $T^2$ statistic, we derive confidence ellipses for the LCs. Finally, the proposed GoF measures are applied on five real data sets in order to demonstrate their applicability.
Impact of Processing Parameters in Plasma Electrolytic Oxidation (PEM) on Corrosion R...
Talal Aljohani
Sami  Aljadaan

Talal Aljohani

and 3 more

April 08, 2021
This study aims to investigate the effect of the processing parameters in plasma electrolytic oxidation (PEO) on the corrosion resistance of magnesium alloy type AZ91. The PEO coatings were prepared on the samples using alkaline-based electrolyte. Both unipolar and bipolar, different frequencies and duty cycles were applied. Corrosion tests, using potentiodynamic polarisation (PDP), linear and cyclic, and electrochemical impedance spectroscopy (EIS) techniques, were applied on the as-received and PEO coated samples. Scanning electron microscopy was used to investigate the surface morphology, e.g. micropores, as well as to measure the thickness of the coated layer with changing the processing parameters. The results show that the size of micropores is interrelated to the duty cycle percentage and current polarities, as the higher frequency causes thinner coating layers, with fewer micropores, consequently higher corrosion resistance. In addition, increasing the duty cycle, a denser and more compact coating was obtained. The XRD results showed missing peak of the α-Mg phase in a PEO coated sample using Bipolar, the highest frequency (1666 Hz) and the highest duty cycle (66.6%). The mils per year calculations showed that the PEO coated have lower corrosion rate by at least 8 times than the as-received alloy.
Simple models to predict vaginal delivery and spontaneous fetal occiput rotation base...
Cheng Chen
Xiaoxing Zhang

Cheng Chen

and 11 more

April 08, 2021
Objective: To develop the prediction models for identifying fetal occiput rotation and vaginal delivery based on intrapartum sonographic findings. Design: Prospective observational study. Setting: Hangzhou, China. Population: Nulliparous women with a singleton cephalic presentation at term. Methods: Serial intrapartum ultrasonography were performed in the latent phase (T1) and every three hours after that (T2, T3 and T4). The managing clinicians performed paired digital vaginal examinations to assess labor progress. Main Outcome Measures: Delivery mode and successful internal fetal head rotation to the occiput anterior (OA) position. Results: 614 women were included, of whom 524 underwent vaginal delivery, and 90 required cesarean section. The percentage of women with fetuses in non-occiput anterior position at the latent phase was 53.9% (331 cases), as 257 women underwent spontaneous rotation to OA position before delivery, 74 were with persistent occiput posterior or transverse position. We developed a model on the basis of the maternal height and middle angel to predict the spontaneous fetal occiput rotation, with the area under the receiver operating characteristic curve (AUC) was 0.667 (95%CI 0.583-0.751). Moreover, a prediction model based on the maternal height and angle of progression to evaluate whether women underwent vaginal delivery was also developed, of which the AUC was 0.738(95% CI: 0.763-0.793). Both models showed satisfactory calibration. Conclusion: Simple models based on maternal characteristics and intrapartum ultrasound findings might provide useful information for predicting vaginal delivery and internal fetal occiput rotation.
Cranial internal hemipelvectomy (iliectomy) with limb sparing for a dog with ilial ch...
Amy Downey
Kyle Mathews

Amy Downey

and 2 more

April 08, 2021
Objective: To describe the outcome following limb-sparing subtotal hemipelvectomy (iliectomy) in a dog with ilial chondrosarcoma. Animal: A 9.5-year-old female spayed Boxer with grade 2 chondrosarcoma of the ilium Study Design: Case report.
Pit viper envenomation in pediatric dogs: 5 cases
Carl Southern
Ashley Allen-Durrance

Carl Southern

and 2 more

April 08, 2021
The objective of this case series is to describe the diagnosis, therapeutic intervention, and outcome of pit viper envenomation in five pediatric dogs. All five puppies survived to discharge, with no known complications from their envenomation or antivenom administration.
Tonic activation of VPAC1 receptors by VIP modulates theta-burst induced LTP in the h...
Nadia Rodrigues
Ana Caulino-Rocha

Nadia Rodrigues

and 2 more

April 08, 2021
Background and purpose Vasoactive intestinal peptide (VIP), acting on both VPAC1 and VPAC2 receptors, is a key modulator of hippocampal synaptic transmission, pyramidal cell excitability and synaptic plasticity phenomena, like long-term depression (LTD), partly through modulation GABAergic disinhibitory circuits. VIP effects on LTP and the involvement of disinhibition were scarcely investigated. Experimental approach The influence of endogenous VIP on CA1 LTP induced by TBS was evaluated in the CA1 area of hippocampal slices using field-excitatory electrophysiological recordings from young-adult Wistar rats using selective VPAC1 and VPAC2 antagonists. Phosphorylation of GluA1 AMPA receptor subunits and Kv4.2 potassium channels was evaluated in hippocampal membranes obtained from such slices by Western blot. Key results Here we show that VIP, acting on VPAC1 (but not VPAC2) receptors, is an endogenous inhibitor of hippocampal LTP induced by theta-burst stimulation (TBS) in the CA1 area of the hippocampus of young adult Wistar rats. This effect is dependent on GABAergic transmission and relies on the integrity of NMDA and CaMKII-dependent LTP expression mechanisms but not on PKA and PKC activity. Furthermore, it regulates the expression and Ser438phosphorylation of Kv4.2 potassium channels responsible for the A-current while inhibiting phosphorylation of Kv4.2 on Thr607. Conclusions and implications Altogether this suggests that endogenous VIP controls the expression of hippocampal CA1 LTP by regulating disinhibition through activation of VPAC1 receptors in interneurons. This may impact the expression and phosphorylation of Kv4.2 K+ channels at hippocampal pyramidal cell dendrites.
The relationship of Vitamin B 12 with Two Symptoms of Shingles: Who has Pain and Who...
İlkay Özer
Günseli Kekeç

İlkay Özer

and 4 more

April 08, 2021
Background; Both herpetic pain and itching in shingles are two symptoms whose pathogenesis has not been elucidated, although they are thought to be due to nerve damage. These two symptoms are difficult to treat and negative impact quality of life. In addition, It is unclear which patient will have the symptoms of itching or pain. Vitamin B 12 is a neurotropic agent which is contributes to the treatment of nerve damage, and effective in treating neuropathic pain and itch. In this study we investigated that is relationship between vitamin B12 both herpetic pain and herpetic itch. Methods; In this study, we investigated the effect of vitamin B12 values on itching and pain symptoms that patients with shingles have in the acute period. Vitamin B 12 values of 53 adults with patients with shingles with herpetic pain or herpetic itching were recorded and compared with the control group. Results; We found that patients with herpetic pain had lower vitamin B12 values than the control group (p=0.046) and patients with herpetic itch (p=0.021). Vitamin B12 values of herpetic itch patients did not show significant difference from the control group (p=0.816). Conclusions; Although vitamin B12 deficiency plays a role in the etiology of herpetic pain, it has no effect on herpetic itching. Our study supports that the etiopathogenesis of HI is different from herpetic pain, and will help studies focusing on herpetic itching etiopathogenesis.
Prognostic Importance of Thrombospondin-1, VEGF, PDGFR- β in Diffuse Large B-Cell Lym...
adnan batman
Rafiye Çiftçiler

adnan batman

and 3 more

April 08, 2021
Purpose: We aimed to investigate the relationship between the staining rates of thrombospondin-1, VEGF and PDGFR-in tissue preparations in patients diagnosed with DLBCL as a result of lymphadenopathy biopsy and their clinical features at the time of diagnosis, response to treatment and prognosis. Materials and Methods: For this purpose, a total of 44 patients with a diagnosis of DLBCL, 24 male and 20 female, and 13 patients diagnosed with control reactive lymphadenopathy, 6 male and 7 female were enrolled. After the pathology preparations of the patient and control groups were stained immunohistochemically with VEGF, PDGFR-β, thrombospondin-1 stains, the clinical characteristics of the patients and the relationship between survival analysis and staining rates were analyzed statistically. Results: When the patients were compared with the control group in terms of VEGF, PDGFR-β, thrombospondin-1 staining rates, we found that staining with PDGFR-β was lower in patients (p = 0.009). Although it was not statistically significant for PDGFR-β, it was observed that 5-year OS and PFS values were low in patients with high levels of expression, on the contrary, 5-year OS was low in patients with high thrombospondin staining rate. A negative correlation was seen between thrombospondin-1 and PDGFR-β (p=0.003, r=-0.440). Conclusion: As a result, although no relationship was found between VEGF and survival in our study, it was observed that PDGFR-β and thrombospondin-1 were effective in prognosis. A negative correlation was seen between thrombospondin-1 and PDGFR-β.
On linking mechanism to invasive species impact
Marc Cadotte

Marc Cadotte

April 08, 2021
Species invasion represents one of the major drivers of biodiversity change globally, yet there is widespread confusion about the nature of non-indigenous species (NIS) impact. This stems from differing notions of what constitutes invasive species ‘impact’ and the scales at which it should be assessed. At local scales, the mechanisms of impact on competitors can be classified into four scenarios: 1) minimal impact from NIS inhabiting unique niche space; 2) neutral impact spread across the community and proportional to NIS abundance; 3) targeted impact on a small number of competitors with overlapping niches; and 4) pervasive impact that is disproportionate to NIS abundance and caused by modifications that filter out other species. I developed a statistical test to distinguish these four mechanisms based on community rank-abundance curves and then created a scale-independent standardized impact score. Using an example long-term dataset, that has high native plant diversity and an abundance gradient of the invasive vine, Vincetoxicum rossicum, I show that impact resulted in either targeted extirpations or widespread biodiversity loss. Regardless of whether NIS impact is neutral, targeted or pervasive, the net outcome will be the homogenization of ecosystems and reduced biodiversity at larger scales, perhaps reducing ecosystem resilience.
COVİD-19 AND HYPERAMYLASEMİA
Ferhat Bacaksız
Berat Ebik

Ferhat Bacaksız

and 3 more

April 08, 2021
Object: Our aim is to evaluate the elevation of pancreatic enzymes in COVID-19 patients and their relationship with severity of COVID-19. Method: In this study, 1378 patients with COVID-19 infection were included. Relation of elevated amylase and lipase levels and co-morbid conditions with the severity of COVID-19 were checked. The effect of hemodynamic parameters and organ failures on pancreatic enzymes and their relations with prognosis were statistically analyzed. Results: There were 678 (%49,2) female patients and 700 (50,8%) male patients. Of all patients, 687 (49,9%) had mild, 691 (50,1%) severe COVID-19 infections. Elevated amylase levels were detected in 23% of patients (n:316). 19% (261) of them had a slight (1-3 times) increase in amylase levels, while 4% (55) had a more than 3 times increase in amylase than normal. Only 6% of patients with elevated amylase leves had the acute pancreatitis according to Atlanta criteria. According to univariate and multivariate analyses, elevated amylase levels was found statistically related with severity of COVID-19 (OR:4,37-p <0,001). And also diabetes mellitus (DM) (OR:1,82-p:0,001), kidney failure (OR:5,18- p< 0,001), liver damage (OR:6,63 p < 0,001), hypotension (OR:6,86-p< 0,001), sepsis (OR:6,20-p:0.008) were found to related to death of COVID-19. Conclusions: Elevated pancreatic enzyme levels in COVID-19 infections is to related to severity of COVID-19 infection and hemodynamic instability. Similar to other organs, the pancreas can be affected by severe COVID-19 infection.
A case of bone lesion in a patient with relapsed chronic lymphocytic leukemia and rev...
Francesca Bacchiarri
Alessandro Gozzetti

Francesca Bacchiarri

and 4 more

April 08, 2021
Skeletal involvement in CLL is very rare. We present a case of ileum bone lesion during in a patient receiving 5th line of therapy. Despite radiotherapy and salvage therapies, subsequent bone lesions led to a fatal outcome. Further studies on the mechanism by which bone disease develops are currently needed.
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