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Free-living amoebae (FLA) are cosmopolitan microorganisms known to be pathogenic to humans who often have a history of contact with contaminated water. Swimming pools and recreational waters are among the environments where the greatest human exposure to FLA occurs. This study aimed to determine the prevalence of FLA in swimming pools and recreational waters, through a systematic review and meta-analysis that included studies published between 1977 and 2021. 71 studies were included and an overall prevalence of FLA in swimming pools and recreational waters of 40.89% (95% CI = 33.97–48.00) was found. Considering the studies published up to 2010 (1977 - 2010) and after 2010 (>2010 - 2021) the prevalence were 51.54% (95% CI = 36.65-66.29) and 37.95% (95% CI = 30.34 – 45.86), respectively. The highest prevalence were found in the American continent (59.52%), in Malaysia (89.33%) and in indoor hot pools 52.27%. In studies that used morphological methods, PCR and both methods simultaneously to identify FLA, the prevalence was 56.41, 22.32 and 39.94%, respectively. Considering only PCR-based studies, the prevalence of Naegleria spp., Acanthamoeba spp., Hartmanella spp. and Vermamoeba spp. was 10.01, 15.38, 16.40 and 16.06%, respectively. There is considerable risk of AFL infection in swimming pools and recreational waters. Recreational water safety needs to be routinely monitored and, in case of risk, locations need to be identified with warning signs and users need to be educated. Swimming pools and artificial recreational water should be properly disinfected. Photolysis of NaOCl or NaCl in water by UV-C radiation is a promising alternative to disinfect swimming pools and artificial recreational waters.

Shimei Yang

and 5 more

Grazing management practices are a major factor regulating nutrient cycling and plant growth in grasslands. However, the response of long-term grazing regimes to ecosystem [carbon](https://cn.bing.com/dict/clientsearch?mkt=zh-CN&setLang=zh&form=BDVEHC&ClientVer=BDDTV3.5.1.4320&q=%E5%85%BB%E5%88%86%E5%BE%AA%E7%8E%AF) and nitrogen [accumulation](https://cn.bing.com/dict/clientsearch?mkt=zh-CN&setLang=zh&form=BDVEHC&ClientVer=BDDTV3.5.1.4320&q=%E5%85%BB%E5%88%86%E5%BE%AA%E7%8E%AF) and plant productivity remains uncertain in karst landscapes. A 17 year-long field experiment, constituting the methods of grazing exclusion (GE), continuous grazing (CG), mowing and grazing (MG), and rotational grazing (RG), was conducted to assess the effects of long-term management measures on plant biomass, ecosystem organic [carbon,](https://cn.bing.com/dict/clientsearch?mkt=zh-CN&setLang=zh&form=BDVEHC&ClientVer=BDDTV3.5.1.4320&q=%E5%85%BB%E5%88%86%E5%BE%AA%E7%8E%AF) and nitrogen stocks in a karst alpine grassland of the Yunnan-Guizhou Plateau. Our results showed that grazing significantly reduced the aboveground biomass (CG, MG, and RG) and root biomass (MG and RG) compared to GE, but there were no differences between the results obtained using the various grazing methods. The root/shoot ratio increased by 55.98% in CG and decreased by 52.96% and 37.14% in MG and RG, respectively, compared to that achieved with GE. Soil organic carbon (SOC) of GE was higher than that of CG, MG, and RG in each soil layer, while it was significantly higher at 0–10 cm and 20–30 cm. Grazing promoted the mean total N content with a significant increase in CG and RG, and significantly increased total P content in each soil layer compared to GE. Grazing significantly decreased the C/N and C/P ratios at each soil depth. GE significantly increased the ecosystem organic carbon stocks (EOCs) and decreased the ecosystem total nitrogen stocks (ETNs). Although there were no significant changes among the grazing methods, the EOCs increased by 22.29% (MG) and 16.31% (RG) and ETNs increased by 7.76% (RG) when compared to those obtained with CG. EOSs were positively correlated with SOC, stoichiometry (C: N: P), and aboveground biomass, while being negatively correlated with TP; ETNs were positively correlated with N and P, while being negatively correlated with C/N, C/P, aboveground biomass, and root biomass. Our results indicate that GE can provide significant improvements in plant recovery and ecosystem organic carbon storage, whereas RG is beneficial for promoting both EOCs and ETNs under the condition of pasturing utilisation in karst grasslands.

Rui Li

and 3 more

Soil erosion is the prominent ecological and environmental problem in karst area of southwest China, which seriously restricts the sustainable development of the region. Determining the priority areas of soil erosion governance and its driving factors can significantly improve the efficiency of prevention and control. However, at present, there are few researches on the priority areas of governance that comprehensively consider karst landform types and management requirements. Based on the minimum administrative unit and karst landform types, this study identified the priority areas of soil erosion control by comprehensive use of spatial clustering method and geographic detectors, and quantified the driving factors and their interactions. The results indicated that: (i) Priority areas within the smallest administrative unit are clustered in the southwest, southeast and northeast of the study area, overlapping with areas of intense erosion; Geomorphological differentiation of multi-factor gradient risk zones is obvious, but the areas with strong erosion are all controlled by bedrock exposure rate, altitude and slope aspect. (ii) The soil erosion in the priority area is concentrated and intense. By treating the priority area, which accounts for 12.77% of the total area, soil erosion can be reduced by 27.66%. (iii) The driving factors have a strong dependence on karst landforms, showing obvious differences in different karst landform areas; Interaction of factors, especially the interaction between human disturbance factors and natural influence factors, can significantly enhance the explanatory power of soil erosion. The research results have important theoretical significance for the planning and control of soil and water loss in karst areas.

Ya Wang

and 4 more

Intense fishing pressure and climate change are major threats to fish populations and coastal fisheries. Larimichthys crocea (large yellow croaker) is a long-lived fish, which performs seasonal migrations from its spawning and nursery grounds along the coast of the East China Sea (ECS) to overwintering grounds offshore. This study used length-based analysis and habitat suitability index (HSI) model to evaluate current life-history parameters and overwintering habitat suitability of L. crocea, respectively. We compared recent (2019) and historical (1971-1982) life-history parameters and overwintering HSI to analyze the fishing pressure and climate change effects on the overall population and overwintering phase of L. crocea. The length-based analysis indicated serious overfishing of L. crocea, characterized by reduced catch yield, size truncation, constrained distribution, and advanced maturation causing a recruitment bottleneck. The overwintering HSI modeling results indicated that climate change has led to decreased sea surface temperature during L. crocea overwintering phase over the last half-century, which in turn led to area decrease and an offshore-oriented shifting of optimal overwintering habitat of L. crocea. The fishing-caused size truncation may have constrained the migratory ability and distribution of L. crocea subsequently leading to the mismatch of the optimal overwintering habitat against climate change background, namely habitat bottleneck. Hence, while heavily fishing was the major cause of L. crocea collapse, climate-induced overwintering habitat suitability may have intensified the fishery collapse of L. crocea population. It is important for management to take both overfishing and climate change issues into consideration when developing stock enhancement activities and policy regulations, particularly for migratory long-lived fish that share a similar life history to L. crocea. Combined with China’s current restocking and stock enhancement initiatives, we propose recommendations for future restocking of L. crocea in China.

Habiba H. AboAlEla

and 10 more

Background: Multisystem Inflammatory Syndrome in Children (MISC) is a phenomenon that appeared in children infected with or exposed to SARS-CoV-2. The typical onset of MISC is 4-6 weeks following SARS-CoV-2 infection and is formulated to be due to an immune response. Methods: Our study retrospectively analyzed data from a tertiary center in UAE of MISC patients who were admitted to either general pediatric wards or pediatric intensive care (PICU) or who came exclusively for follow-up (post PICU admission) from May 2020 to August 2021.   Results: The total sample size is 50 patients and the study included a comparison of PICU admissions with none PICU admissions. The PICU sample size was 18 patients, 50% females, with mean age of 8.3 years all were previously healthy. PICU patients had deranged blood counts with a lower hemoglobin count, a more pronounced lymphopenia and thrombocytopenia along with hypoalbuminemia. PICU patients presented with relatively higher inflammatory markers: CRP, PCT, ferritin and D-dimer. Immunological studies were significantly higher for IL-6 levels in PICU patients. On echocardiography, higher myocardial dysfunction was more notable in patients admitted to PICU. Children admitted in PICU were provided with more extensive therapy. As part of our study course, we re-evaluated our PICU patients twice, once at 48 hours post PICU admission and again 4-6 weeks after discharge from the hospital. No deaths have been recorded in the cohort. Conclusion: This study evaluated risk factors of MISC and potential severity features. Follow up of patients on discharge showed improvement across all domains.

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Yuval Shafir

and 8 more

INTRODUCTION: Transvenous Lead Extraction (TLE) is usually performed via a superior approach. Predictors and outcomes of TLE requiring femoral vein bailout are poorly defined. We aimed to analyze predictors and consequences of TLE requiring femoral bailout. METHODS: A single tertiary center cohort of 421 consecutive patients who underwent TLE between May 2010 and February 2020 were analyzed. Venography was routinely performed before system upgrade to identify occluded veins. Patients were divided into 2 groups according to their need for femoral bailout extraction. RESULTS: A total of 928 leads were extracted with femoral bailout approach was needed in 71 leads(7.7%) among 49 patients(11.6%). A higher proportion of right ventricular(RV) leads required femoral bailout approach compared with right atrial(RA) leads[51/499(10.2%) vs 18/326(5.5%);p=0.02]. Femoral bailout was more common among younger patients, longer lead dwell time, more pocket entries, higher number of extracted leads, presence of abandoned leads and among patients with vascular occlusion. Following multivariate analysis, presence of abandoned leads, vascular occlusion and younger age remained a significant predictor for femoral bailout. Femoral bailout resulted in higher rates of major complications [5/49(10.2%) vs 12/372(3.2%);p=0.05] without intra-procedural mortality and no additional 30-day mortality[2/49(4.1%) vs 33/377(8.8%);p=0.39]. CONCLUSION: TLE of abandoned leads, occluded veins and younger age were found to be predictors of femoral bailout requirement. Despite higher rates of major complications in femoral TLE bailout, mortality was not increased. Venography prior to TLE should be considered for procedure planning.

Manuel E. Izquierdo

and 21 more

Background:  Heterozygote carriers of potentially pathogenic variants in the cystic fibrosis transmembrane conductance regulator ( CFTR) gene have increased asthma risk. However, the frequency and impact of CFTR variation among individuals with asthma is unknown. Objective: To determine whether potentially pathogenic  CFTR variants associate with disease severity and whether individuals with two potentially pathogenic variants exist in a severe asthma-enriched cohort . Methods: We analyzed sequencing data spanning a 190.5Kb region of  CFTR in participants from the Severe Asthma Research Program (SARP1-3). Potentially pathogenic, rare  CFTR variants (frequency<0.05) were classified as CF-causing or of varying clinical consequences (VVCC) (CFTR2.org). Regression-based models tested for association between  CFTR genotypes (0-2 potentially pathogenic variants) and severity outcomes. Results: Of 1401 participants, 9.5% (134) had one potentially pathogenic variant, occurring more frequently in non-Hispanic white (NHW, 10.1% [84 of 831]) compared to African American individuals (AA, 5.2% [22 of 426]). We found ≥2 potentially pathogenic  CFTR variants in 1.4% (19); 0.5% (4) of NHW and 2.8% (12) of AA. Potentially pathogenic  CFTR variant genotypes (≥1 or ≥2 variants) were not cumulatively associated with lung function or exacerbations. In NHW, we found three F508del compound heterozygotes with F508del and a VVCC (two 5T;TG12[c.1210-11T>G] and one Arg1070Trp) and a homozygote for the VVCC, 5T;TG12. Conclusions: We found potentially pathogenic  CFTR variants within a severe asthma-enriched cohort , including three compound heterozygote genotypes variably associated with CF in NHW individuals. These findings provide the rationale for  CFTR sequencing and phenotyping of CF-related traits in individuals with severe asthma.

Hanan Al-Abboh

and 2 more

A Novel MECOM Variant Associated with Congenital Amegakaryocytic Thrombocytopenia and Radioulnar Synostosis Hanan Al-Abboh1, Akmal Zahra1 and Adekunle Adekile1,2Pediatric Hematology Unit, Mubarak Hospital1 and Department of Pediatrics, Faculty of Medicine, Kuwait University2, Kuwait Address Correspondence to: Professor Adekunle Adekile Department of Pediatrics Faculty of Medicine Kuwait University PO Box 24923 Safat 13110 Kuwait Email: adekunle.adekile@ku.edu.kw Tel: +96525319486To the EditorCongenital radioulnar synostosis (RUS) is a rare developmental anomaly of proximal fusion of the radius and ulna, resulting in limited pronation and supination of the forearm. It may accompany other abnormalities in the skeleton, kidney, heart and aneuploidy syndromes1,2. A subset of patients with RUS present with bone marrow failure (BMF) syndromes, characterized by amegakaryocytic thrombocytopenia (RUSAT), progressing to myelodysplasia and pancytopenia2,3. The hematological manifestations are quite variable, with some presenting with severe BMF in childhood, while others are mild and may not present until adulthood.Heterozygous germline variants in the homeobox A11 (HOXA11) gene were the first to be associated with RUS and designated RUSAT14, but lately, several families have been described with variants in the MDS1 and EVI1 complex (MECOM) locus, and referred to as RUSAT22,5,6. Many of these variants appear de novo , while others follow an autosomal dominant inheritance. We, hereby, report the case of a Kuwaiti patient who presented with congenital amegakaryocytic thrombocytopenia (CAMT) in the neonatal period and later noticed to have RUS. Whole exome sequencing revealed a novel MECOM variant.A.A. is a male Kuwaiti, the first child of consanguineous parents and was first seen at the age of 36 days, following antenatal ultrasound diagnosis of bilateral hydronephrosis and right renal cyst. He was a product of induced vaginal delivery with a birth weight of 2.3 kg. After delivery, he was kept under observation in the neonatal intensive care unit. His CBC showed isolated thrombocytopenia (Plt 34 x109/L). He received several platelet transfusions, as well as IVIG twice. Postnatal abdominal ultrasound showed multicystic right kidney, in addition to bilateral hydronephrosis. The mother had no history of thrombocytopenia during pregnancy and there was no other pertinent family history.Physical examination at presentation showed 2 café-au-lait spots, one on the back, measuring 1x2 cm and another over the left leg, that was less than 0.6 cm. There were no obvious dysmorphic features and other systems were unremarkable. CBC showed WBC 11.2 x109/L Hb 10.4 g/dL, MCV 83fl, Plt 49 x109/L, ANC 1.8 x109/L. Renal function tests were normal. Blood film showed no abnormal cells; there was true thrombocytopenia with giant forms. Antiplatelet antibody was negative. Abdominal ultrasound at age 1 month showed complete replacement of the right kidney by cystic changes with left moderate hydronephrosis. Skeletal survey was reportedly normal.Bone marrow biopsy showed normal distribution of granulocytic and erythroid precursors, with severe suppression of megakaryocytosis, consistent with a bone marrow failure syndrome. Chromosomal breakage study was normal. The patient was diagnosed with right undescended testis, as well as right inguinal hernia that were operated at age 1 year and 10 months. At the age 2 and a half years, A.A. was noticed to have limited bilateral arm movement supination and pronation. The mother volunteered that she has a similar defect. X-rays confirmed that the child had bilateral radioulnar synostosis. Whole exome sequencing showed that the patient is heterozygous for a previously-unreported MECOM gene, c.2282A>G mutation. Unfortunately, the parents have not been screened for these mutations.The patient has been under follow up for 4 years, his platelet count has been stable, ranging between 40-50 x109/L, with no bleeding tendency. In spite of his limited arm rotation, he currently functions normally in his daily activities, however, his hand writing skills and ability to engage in sports are yet to be observed since he is still pre-school age. Platelet transfusion is reserved only for severe bleeding, which he has not had. Bone marrow transplant may be considered in future if his bone marrow failure worsens and/or his marrow shows dysplastic changes.Dokal et al3 were the first to report an association between RUS and late-onset BMF, while Thompson et al described its association with CAMT and linked it to the c.872delA ,p.Asn291Thrfs3 variant of the HOXA11gene4,7. More recently, several germline mutations in the MECOM locus have been reported and appear to be the more common cause of RUSAT. Indeed, no other cases of HOXA11 mutations linked to RUSAT have been described since the initial report. Niihori et al8 reported the first 3 heterozygous MECOMmutations in 3 sporadic patients. These variants and those subsequently reported by Walne et al2 are in a highly conserved cluster within 10 amino acids (aa750-760) and impact on either the highly conserved Cys2His2 zinc finger motif (zinc finger 8, aa733-755) or the adjacent linker motif (aa756-760). It has been shown that removal of the 8th zinc finger causes granulopoiesis arrest while mutations and deletions in other parts of the complex, outside the 8th and 9th fingers, are associated with hematological disorders without RUS9.MECOM codes for a zinc finger transcription factor with important roles in normal development and oncogenesis and is involved in the regulation of embryonic development and hematopoietic stem-cell renewal. Hence the phenotype in individuals with these mutations is very variable ranging from BMF to different skeletal, cardiac, renal malformations, B cell deficiency and sensorineural deafness.Our patient showed a previously unreported variant in the region of the 8th zinc finger of the MECOM locus. This c.2282A>G missense variant results in the tyrosine to cysteine substitution at codon 761 (p.Tyr761Cys). The amino acid is in the Zinc finger, C2H2 and Zinc finger, C2H2-like protein domains and is highly evolutionarily conserved. Unfortunately, the parents were not screened for the mutation, however, the mother shows RUS, with normal blood counts. This is consistent with the marked variability in the clinical phenotype. The father is also physically and hematologically normal.Apart from thrombocytopenia, our patient also had renal abnormalities – hydronephrosis and multicystic kidney disease. The natural history of his condition is that he may develop pancytopenia and/or myelodysplasia in the future. He is under close follow up and will be considered for bone marrow transplantation if his condition worsens. In the meantime, he remains hypomegakaryocytic with a platelet count at 30 – 50 x 109/l while other blood cellular elements are normal. His renal function and hearing are being monitored, but still remain normal.AcknowledgementsWe thank the patient’s family for allowing us to report this case. The whole exome sequencing was done at the Laboratory of Genetics and Genomics, Cincinnati Children’s Hospital, Cincinnati, Ohio.References1. Rizzo R, Pavone V, Corsello G, Sorge G, Neri G, Opitz JM. Autosomal dominant and sporadic radio-ulnar synostosis. Am J Med Genet.1997;68(2):127-134.2. Walne A, Tummala H, Ellison A, et al. Expanding the phenotypic and genetic spectrum of radioulnar synostosis associated hematological disease. Haematologica. 2018;103(7):e284-e287.3. Dokal I, Ganly P, Riebero I, et al. Late onset bone marrow failure associated with proximal fusion of radius and ulna: a new syndrome.Br J Haematol. 1989;71(2):277-280.4. Thompson AA, Nguyen LT. Amegakaryocytic thrombocytopenia and radio-ulnar synostosis are associated with HOXA11 mutation. Nat Genet. 2000;26(4):397-398.5. Germeshausen M, Ancliff P, Estrada J, et al. MECOM-associated syndrome: a heterogeneous inherited bone marrow failure syndrome with amegakaryocytic thrombocytopenia. Blood Adv. 2018;2(6):586-596.6. Ripperger T, Hofmann W, Koch JC, et al. MDS1 and EVI1 complex locus (MECOM): a novel candidate gene for hereditary hematological malignancies. Haematologica. 2018;103(2):e55-e58.7. Thompson AA, Woodruff K, Feig SA, Nguyen LT, Schanen NC. Congenital thrombocytopenia and radio-ulnar synostosis: a new familial syndrome.Br J Haematol. 2001;113(4):866-870.8. Niihori T, Ouchi-Uchiyama M, Sasahara Y, et al. Mutations in MECOM, Encoding Oncoprotein EVI1, Cause Radioulnar Synostosis with Amegakaryocytic Thrombocytopenia. Am J Hum Genet.2015;97(6):848-854.9. Nielsen M, Vermont CL, Aten E, et al. Deletion of the 3q26 region including the EVI1 and MDS1 genes in a neonate with congenital thrombocytopenia and subsequent aplastic anaemia. J Med Genet.2012;49(9):598-600.

Hoda Abdelgawad

and 2 more

57-years old man presented with exertional dyspnea. An early systolic murmur was heard over the aortic areas 2D and 3D Echocardiography revealed unicuspid , unicommissural aortic valve (UAV) with a characteristic “teardrop” lateral orifice (Figure A) and moderate valve stenosis (3D planimetered aortic valve area (AVA) is 1.1cm2) (Figure B) Continuous wave Doppler across aortic valve (AV) showed high peak and mean systolic gradients of 85 and 60mmHg respectively.(Figure C). 2D /3D Transesophageal Echocardiography (TOE) revealed a subaortic ridge attached to the posterior annulus (Arrow) (Figure D) Further En-face viewing of the aortic valve from the left ventricular outflow tract (LVOT) perspective showed a shelf-like ridge extending from the commissure to the cusp (Arrow) (Figure E) Zoomed mode of the aortic- LVOT junction confirmed the presence of the subaortic ridge seen attached to the posterior aortic annulus near the commissural opening (Figure F) The patient was referred for surgical consultation .. Unicupid aortic valve (UAV) is a rare congenital anomaly that has.2 subtypes ; unicomissural and acommissural subtypes. Both can present with variable degrees of the aortic stenosis (AS) and/or aortic valve regurgitation (AR).UAV has more early, accelerated and severe valvular degeneration in addition to smaller orifice in comparison with bicuspid and tricuspid aortic valve. Echocardiography is the gold standard for diagnosis and evaluation of the AV morphology and function and the associated disorders such as ventricular septal defect , aortopathy and subaortic obstruction.. Surgical aortic valve replacement (AVR) and repair of the associated anomalies are the most common treatment modality .

Esin Isik

and 7 more

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