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Inappropriate shock in Brugada syndrome: incidence and predictors in patients with a...
Gavino Casu
Etelvino Silva

Gavino Casu

and 8 more

January 18, 2021
Abstract Background: Subcutaneous implantable cardioverter defibrillators (S-ICDs) avoid complications secondary to transvenous leads, but inappropriate shocks (ISs) are frequent. Furthermore, IS data from patients with Brugada syndrome (BrS) with an S-ICD are scarce. Objective: We aimed to establish the incidence, mechanisms, and predictors of S-ICD in this population. Methods: We analyzed the clinical and electrocardiographic characteristics, automated screening test data, device programming, and IS occurrence in adult patients with BrS with an S-ICD. Results: Thirty-nine patients were enrolled (69% male, mean age at diagnosis 46±13 years, mean age at implantation 48±13 years). During a mean follow-up of 26±21 months, 18% patients experienced IS. Patients with IS were younger at the time of diagnosis (36±8 versus 48±13 years, p=0.018) and S-ICD implantation (38±9 versus 50±23 years, p=0.019) and presented with spontaneous type 1 Brugada ECG pattern more frequently at diagnosis or during follow-up (71% versus 25%, p=0.018). During automated screening tests, patients with IS showed lower QRS voltage in the primary vector in the supine position (0.58±0.26 versus 1.10±0.35 mV, p=0.011) and lower defibrillator automated screening score (DASS) in the primary vector in the supine (123±165 versus 554±390 mV, p=0.005) and standing (162±179 versus 486±388 mV, p=0.038) positions. Age at diagnosis was the only independent predictor of IS (hazard ratio=0.873, 95% confidence interval: 0.767-0.992, p=0.037). Conclusion: IS was a frequent complication in patients with BrS with an S-ICD. Younger age was independently associated with IS. A more thorough screening process might help prevent IS in this population.
Insights into the mechanism of atrial tachycardia with over two types of reentrant ci...
Fan Wang
Bai Wang

Fan Wang

and 8 more

January 17, 2021
Background: Multiple atrial tachycardias (ATs) in one patient usually require more complex ablation procedures. Despite the superior accuracy and understanding of conduction features provided by high-resolution mapping, Multiple ATs are still associated with high recurrence rates, and other mechanisms may play a role. Therefore, we aimed to uncover the substrates maintaining these multiple reentrant circuits and the probable mechanisms for the high occurrence of arrhythmia. Methods: Mapping via the Carto system was carried out in 8 patients with more than two types of reentrant circuits during ablation. Functional conduction block (FCB) regions were marked and further analyzed. Results: Twenty sustained ATs were mapped in the 8 patients. Five of these patients exhibited a potential FCB region that changed between different ATs. The potentials of these regions converted between double potentials (DPs), fractionated potentials (FPs) and normal potential due to the different ATs. The FCB regions were the main obstacles and the center of the reentrant circuit in 8 of 14 ATs, and in the other ATs, these regions played a role in reorganizing the conduction pathway. In the activation mapping, the FCB areas were never the target ablation site. Conclusion: The potential FCB region is common in ATs with more than two types of reentrant circuits, especially in scar-related localized reentry. The convertibility of FCB regions provide one of the critical substrates in maintaining multiple ATs. The changefulness of this substrate may be one of the important causes of the high recurrence of related ATs
RISK FACTORS AND CLINICAL CHARACTERISTICS OF BK POLYOMAVIRUS INFECTION AFTER HEMATOPO...
Gamze Kalın Ünüvar
Zeynep Ture

Gamze Kalın Ünüvar

and 4 more

January 17, 2021
BK polyomavirus (BKPyV) infections are an important cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Hemorrhagic cystitis (HC) may occur in patients undergoing HSCT due to the BKPyV reactivation. This study aimed to assess risk factors, clinical characteristics and treatment options of BKPyV infections after HSCT. A total of 54 patients with HSCT were retrospectively evaluated and BKPyV disease was found in 24 (44%). HC was seen in 20 (83%) of patients with BKPyV disease. The median age of patients was 42 and 50% of them were male. The most common underlying disease was Acute Myeloid Leukemia (62%). Five patients had autologous and 15 patients had allogeneic HSCT. The median time to engraftment was 15 days. GVHD was seen only in 7 patients. The median time elapsed to BKPyV disease after HSCT was found as 60 days. Nineteen patients with BKPyV disease had grade 3 and one patient had grade 2 HC. While BKPyV viremia was positive in five patients, viruria was detected in all patients. Eighteen (75%) of the patients with BKPyV disease were treated with cidofovir (5mg/kg IV) and 11 with ciprofloxacin (800 mg/day). Four of the patients who received intravesical cidofovir (dose). The complete response was obtained 53% of patients with BKPyV disease. In conclusion, BKPyV disease is an emerging clinical problem after HSCT causing morbidity and mortality. It can develop especially in the early period after allogeneic stem cell transplantation. This situation has been associated with the use of immunosuppressive treatments after transplantation. Close monitoring of BK virus in high-risk patients can be an important method to improve the complication in the early period.
The Correlations Between Epidemiological and Clinical Characteristics, laboratory tes...
Bobby Branson
Ramin Tavakoli

Bobby Branson

and 5 more

January 17, 2021
Background: The role of laboratory parameters and the relationship of them with radiology reports, CT scan and clinical outcomes in screening of COVID-19 patients not been definitely established, but this disease presented a major challenge in the field of clinical tests, radiology reports, clinical outcomes that help to monitoring and treatment COVID-19 disease. Methods: This study was performed on 340 suspected COVID-19 patients, who presented to Chamran Hospital, Shiraz University of Medical Sciences Shiraz, Iran from 20 February to 31 August, 2020. Information each patient’s will be completed using a data collection forms based on records. The evaluation of lungs involvement in CT scan and their relationship with laboratory indicator including biochemical and hematological factors, is the best scale for the severity and prognosis of Covid 19 patients. Results and Conclusion: The findings of this study indicated ALT, AST, CRP, NEU, LDH, and Urea have very good accuracy in predicting cases with positive RT-PCR for COVID-19, respectively. In this study we shown the correlation of clinical and laboratory findings with CT-based quantitative score of pulmonary involvement in COVID-19 pneumonia and attempted that our findings could be usable to development future clinical research associated with COVID-19 infection and show the relationship of reports CT scan and clinical outcomes in the diagnosis and severity of patients with COVID-19.
Successful determination of imatinib dosage by therapeutic drug monitoring in a case...
Ryosuke Nakahara
Takahiro Sumimoto

Ryosuke Nakahara

and 4 more

January 17, 2021
Imatinib is used as first-line treatment for chronic myeloid leukemia (CML) even in patients with impaired renal function. We successfully used therapeutic drug monitoring to determine the dose for re-administration of imatinib in a CML patient who initiated dialysis for acute renal dysfunction associated with the initial imatinib therapy.
Genetically proxied growth differentiation factor 15 levels and body mass index
Ville  Karhunen
Susanna Larsson

Ville Karhunen

and 2 more

January 17, 2021
Growth-differentiation factor 15 (GDF15) is an inflammatory cytokine involved in energy homeostasis. Its circulating levels are acutely increased by the type 2 diabetes medication metformin, resulting in reduced appetite and weight loss. We identified a genetic variant at the GDF15 gene to proxy a small, lifelong increase in circulating GDF15 levels, and leveraged it in colocalization and Mendelian randomization analyses to investigate the effects of chronically elevated GDF15 levels on body mass index (BMI) and type 2 diabetes liability. The results provide human genetic evidence supporting that chronically elevated GDF15 levels increase BMI. There was no genetic evidence to support bi-directional effects, or that chronically elevated GDF15 levels directly affect liability to type 2 diabetes. Our results contrast the BMI lowering effects of an acute increase in GDF15 levels observed after metformin use. These findings have direct implications for informing pharmacological strategies aimed at targeting GDF15 levels for weight loss.
Hypertension and chronic cor pulmonale were the independent risk factors for a prolon...
Hong Wang
TAO YANG

Hong Wang

and 8 more

January 17, 2021
Background: AECOPD is a severe status of COPD. The prolonged length of hospital stay (LHS) was associated with poor prognosis and higher medical costs in AECOPD patients. Identification of the risk factors for prolonged LHS will help physicians provide targeted and personalized interventions, reduce LHS, and avoid unnecessary health services in COPD patients. This study aimed to explore the risk factors for prolonged LHS in hospitalized AECOPD patients. Methods: In this multicenter cross-sectional study, 598 AECOPD patients were screened. In the end, the LHS of 111 were <7 days (Normal LHS, N-LHS), 218 were 7-10 days (Mild Prolonged LHS, MP-LHS), and 100 were≥11 days (Severe Prolonged LHS, SP-LHS). Demographic data, underlying diseases, symptoms, and laboratory findings were collected. Multiple logistics regression was performed to investigate the independent risk factors for prolonged LHS in AECOPD patients. Results: The significant differences in 11 variables were found by univariate analysis. Since significant collinearities among white blood cells (WBC), neutrophils (NS), and NS% were observed, WBC and NS% were excluded. Therefore, 9 factors were included in multiple logistics regression. Subsequently, our results identified that the rates of hypertension and chronic cor pulmonale (CCP) were independently associated with prolonged LHS in AECOPD patients. Conclusions: Collectively, our results suggested that complications of hypertension and CCP were at a higher risk of prolonged LHS in AECOPD patients. It also indicated that AECOPD combined with hypertension and/or CCP probably more severe. Then, more extensive management should be initially administrated.
High Density Intramural Mapping of Post-Infarct Premature Ventricular Contractions.
Eugene Downar
Michiel Janse

Eugene Downar

and 6 more

January 17, 2021
Background: Spontaneous ventricular premature contractions (PVCs) in the post infarct milieu is assumed to be due to automaticity. However, the mechanism has not been studied with appropriate mapping tools. Objective: To study the mechanism of spontaneous PVCs with high density intramural mapping in a canine model, to test the hypothesis that post-infarct PVCs are due to re-entry rather than automaticity. Methods: In 15 anesthetized dogs, using 768 intramural unipolar electrograms, simultaneous recordings were made. After 30 mins of stabilization, recordings were made during the first 10 minutes of ischemia, and activation maps were constructed of individual beats. Acute ischemia was produced by clamping the left anterior descending coronary artery proximal to the first diagonal branch. The analysis was limited to the activation pattern of spontaneous ventricular beats. Results: In all experiments ST-T alternans occurred. In 8 of 15 dogs spontaneous ventricular beats occurred. In all 8 of these experiment earliest, ectopic activity occurred in the endocardium, well within the ischemic zone. From there, activity spread rapidly along the subendocardium, with endo-to epicardial spread along the non ischemic myocardium. Epicardial breakthrough always occurred at the border of the ischemic myocardium. In 3 dogs, delayed potentials were observed, which were earliest at the ischemic epicardium and extended transmurally with increasing delay towards the endocardium, where they culminated in a premature beat. Conclusion: Graded responses that occur with each sinus beat intramurally, when able to propagate from epicardium to endocardium is the mechanism by which PVCs are generated in post-infarct myocardium.
Stability of African swine fever virus on contaminated spray dried porcine plasma
Melina Fischer
Jutta Pikalo

Melina Fischer

and 3 more

January 17, 2021
African swine fever (ASF) is a viral disease that affects members of the Suidae family. The notifiable disease is considered a major threat to the pig industry, animal health, and food security worldwide. According to the European Food Safety Authority, ASF virus (ASFV) survival and transmission in feed and feed materials is a major research gap. Against this background, the objective of this study was to determine the survival of ASFV on re-contaminated spray dried porcine plasma (SDPP) when stored at two different temperatures. To this means, commercial SDPP granules were contaminated with high titers of ASFV in a worst-case re-contamination scenario. Three samples per time point and temperature condition were subjected to blind passaging on macrophage cultures and subsequent haemadsorption test to determine residual infectivity. In addition, viral genome was detected by real-time PCR. The results indicate that heavily re-contaminated SDPP stored at 4°C remains infectious for at least five weeks. In contrast, contaminated SDPP stored at room temperature displayed a distinct ASFV titer reduction after one week and complete inactivation after two weeks. In conclusion, the residual risk of ASFV transmission through re-contaminated SDPP is low, if SDPP is stored at room temperature for a period of at least two weeks before feeding.
The T- Graft to Control Nasal Length and Nasal Tip Position
Dirk Jan Menger

Dirk Jan Menger

January 17, 2021
The T-graft is a new tool in the armament of structural rhinoplasty. The graft makes it easy to create a well- balanced nasal framework both for beginners and more experienced rhinoplastic surgeons. Due to its multifunctional character the T-graft allows the surgeon to control nasal length as well as nasal tip projection and -rotation. The T-graft is indicated in many anatomical features like in patients with a short nose or heavy soft tissue envelope, but also in patients with under projection of the nasal tip, under- or over-rotation of the nasal tip and deviations of the caudal nasal septum.
A Simple Improvement on Existing Technology to Enhance Transseptal Puncture and Left...
Gregory Feld
Jonathan Hsu

Gregory Feld

and 1 more

January 17, 2021
A document by Gregory Feld, written on Authorea.
MdNup62 interactions with MdHSFs involved in flowering and heat-stress tolerance in a...
Chenguang Zhang
Na An

Chenguang Zhang

and 11 more

January 17, 2021
Because of global warming, the apple flowering period is occurring significantly earlier, increasing the probability and degree of freezing injury. Moreover, extreme hot weather has also seriously affected the development of apple industry. Nuclear pore complexes (NPCs) are main channels controlling nucleocytoplasmic transport, but their roles in regulating plant development and stress responses are still unknown. Here, we analysed the components of the apple NPC and found that MdNup62 interacts with MdNup54, forming the central NPC channel. MdNup62 was localized to the nuclear pore, and its expression was significantly up-regulated in ‘Nagafu No. 2’ tissue-cultured seedlings subjected to heat treatments. To determine MdNup62’s function, we obtained MdNup62-overexpressed (OE) Arabidopsis and tomato lines that showed significantly reduced high-temperature resistance. Additionally, OE-MdNup62 Arabidopsis lines showed significantly earlier flowering compared with wild-type. Furthermore, we identified 62 putative MdNup62-interacting proteins and confirmed MdNup62 interactions with multiple MdHSFs. The OE-MdHSFA1d and OE-MdHSFA9b Arabidopsis lines also showed significantly earlier flowering phenotypes than wild-type, but had enhanced high-temperature resistance levels. Thus, MdNUP62 interacts with multiple MdHSFs during nucleocytoplasmic transport to regulate flowering and heat resistance in apple. The data provide a new theoretical reference for managing the impact of global warming on the apple industry.
The Influence of Constipation on Asthma: A Real-world, Population-based Cohort Study
Yen Chu Huang
Meng-Che Wu

Yen Chu Huang

and 3 more

January 17, 2021
Background Among respiratory diseases, asthma is one of the most burdensome disorder worldwide. Growing evidence disclose gut dysbiosis may contribute to asthma via the gut-lung axis. Constipation can lead to alteration of the gut microflora. The clinical impact of constipation on asthma has not been researched. Therefore, we aim to assess the risk of asthma in constipated patients by a nationwide population-based cohort study. Methods We analyzed 82421 constipated patients and 82421 individuals without constipation between 1999 and 2013 from the Taiwanese National Health Insurance Research Database. Analysis of propensity score was utilized to match age, gender, comorbidities, and medications at a ratio of 1:1. Besides, multiple Cox regression analysis was performed to evaluate the adjusted hazard ratio of asthma. Furthermore, sensitivity tests and a stratified analysis were conducted. Results The incidence of asthma was 10.8 per 1,000 person-years in the constipation group, which was higher than the rate of 5.6 per 1,000 person-years observed in the non-constipation group. After adjustment for age, gender, comorbidities, and medications, constipated patients had a 1.91-fold greater risk of asthma compared to those without constipation (adjusted hazard ratio [aHR]: 1.91 (95% C.I. 1.84-1.99). In subgroup analyses, patients aged 20-39 years had a 2.04-fold highest risk of asthma in the constipation cohort (aHR:2.04, 95% CI, 1.84-2.26). Besides, the severity of constipation is associated with an increased risk of asthma; the aHR was 1.76 (1.69-1.85), 2.15(2.03-2.27), and 2.29(2.10-2.49) for < 3 times, 3-12 times, and ≥12 times of laxatives prescription within one year, respectively. (p<0.001) Moreover, constipated patients had a higher likelihood of asthma, regardless of gender, comorbidities, and medications. Conclusion Constipation relates to a significantly increased risk of asthma. Physicians should be aware of the possibility of asthma in constipated people. Further research is warranted to investigate the possible pathological mechanisms of this association.
Corticosteroid therapy for 2019-nCoV infected patients: a case series of 8 mechanical...
Mabrouk AL-Rasheedi
Yasir Alhazmi

Mabrouk AL-Rasheedi

and 6 more

January 17, 2021
Objective To report a series of eight cases of severe acute respiratory syndrome due to 2019-nCoV infection (Covid-19- Bilateral infiltration) who were successfully treated with high-dose short-term corticosteroid therapy.
Hospital survival associated with the use of thromboprophylaxis in patients with seve...
Víctor M. Camarillo Nava
José Vicente  Rosas

Víctor M. Camarillo Nava

and 6 more

January 17, 2021
Hospital survival associated with the use of thromboprophylaxis in patients with severe COVID-19 infection Survival and thromboprophylaxis in COVID-19 Abstract Introduction: It has been described that patients with severe or critical infection by COVID-19 suffer an inflammatory state that conditions a high thrombotic risk. However, there is little information on how to address thrombotic risk, coagulopathy, and anticoagulant therapy in these patients. Objective: To evaluate the use of thromboprophylaxis in patients with severe COVID-19 infection associated with longer survival. Material and methods: Retrospective cohort study, in a 2nd level hospital. 340 records of patients hospitalized for severe COVID-19 infection were reviewed, and 171 were included in the final analysis. Sociodemographic data, previous pathologies, days of hospital stay, respiratory parameters were evaluated; blood gas, hematic cytometry, DHL, C-reactive protein (CRP), antiviral treatment, thromboprophylaxis, use of steroids and use of antibiotics, the study variable was survival associated with the use of LMWH. Descriptive, inferential statistics, univariate and multiple models were used. Results: Advanced age, PaO2 / FiO2 index> 200 and high CRP were associated with a higher probability of death. And the greater the number of days of use of thromboprophylaxis; the higher the degree of protection. The PaO2 / FiO2 index> 200 (adjusted HR 0.270; 95%CI;. 0.100-0.727) and greater number of days with thromboprophylaxis (adjusted HR, 0.576; 95%CI;. 0.460 – 0.721) during hospitalization, were factors associated with hospital survival. Conclusions: In this study we found evidence to recommend the use of thromboprophylaxis from the first hours of admission in adult patients with severe COVID-19 as long as there are no contraindications for it, due to the increase in hospital survival. KEY WORDS: Thromboprophylaxis, LMWH, SARS-CoV-2, survival, Severe COVID-19 infection.
Are Average Platelet Volume (MPV), Red Cell Distribution Width (RDW) and Platelet Dis...
Erkan Dalbaşı
Omer Lutfi Akgül

Erkan Dalbaşı

and 1 more

January 17, 2021
Background: Acute appendicitis (AA) is the most common cause of surgery performed for acute abdomen. The standard treatment for AA patients has been appendectomy for more than a century. use of broad-spectrum antibiotics, the medical treatment option has come to the fore in the treatment of uncomplicated AA. Aim: Evaluate whether WBC, platelet count, MPV, PDW, RDW, and C-reactive protein (CRP) values of patients diagnosed with uncomplicated AA clinically, with laboratory tests and radiologically with abdominal CT could be a marker for choosing medical or surgical treatment. Material and Method: 519 patients aged between 20 and 65 years who were diagnosed with uncomplicated AA by abdominal CT in our centre between January 2016 and January 2019 were retrospectively analysed. . The presence of at least one of the criteria of 7 mm or more appendix diameter and oedema or fluid accumulation around the appendix was accepted as uncomplicated AA. After the diagnosis of AA, 223 patients were treated medically, while 296 patients underwent laparoscopic appendectomy. The first group included patients who were treated medically and the second group included patients who underwent laparoscopic appendectomy. Results: Group 2 patients had higher mean platelet count (p <.005) and RDW (p = .003) values compared to Group 1 patients, while mean PDW (p <.001) values were lower compared to those of Group 1 patients. The differences between the mean WBC, CRP and MPV values of the groups were not statistically significant (p>0.05). Conclusions: The standard treatment for acute appendicitis is surgery. Recently, studies supporting antibiotic therapy have been conducted in patients diagnosed with AA. As a result, we think that PDW, RDW, and platelet values in patients diagnosed with uncomplicated AA may be a guide in choosing patients to be treated with surgery or antibiotics. Key Words: acute appendicitis, laparoscopic appendectomy, antibiotic therapy.
The COVID-19 Epidemic in Madagascar: clinical description and laboratory results of t...
Rindra Randremanana
Soa-Fy Andriamandimby

Rindra Randremanana

and 29 more

January 17, 2021
Background: Following the first detection of SARS-CoV-2 in passengers arriving from Europe on 19 March 2020, Madagascar took several mitigation measures to limit the spread of the virus in the country. Methods: Nasopharyngeal and/or oropharyngeal swabs were collected from travellers to Madagascar, suspected SARS-CoV-2 cases, and contact of confirmed cases. Swabs were tested at the national reference laboratory using real-time RT-PVR. Data collected from patients were entered in an electronic database for subsequent statistical analysis. All distribution of laboratory confirmed cases were mapped and six genomes of viruses were fully sequenced. Results: Overall, 26,415 individuals were tested for SARS-CoV-2 between 18 March and 18 September 2020, of whom 21.0% (5,553/26,145) returned positive. Among laboratory-confirmed SARS-CoV-2 positive patients, the median age was 39 years (CI95%: 28-52), and 56.6% (3,311/5,553) were asymptomatic at the time of sampling. The probability of testing positive increased with age with the highest adjusted odds ratio of 2.2 [95% CI: 1.9-2.5] for individuals aged 49 years and more. Viral strains sequenced belong to clades 19A, 20A, and 20B in favour of several independent introduction of viruses. Conclusions. Our study describes the first wave of the COVID-19 in Madagascar. Despite early strategies in place Madagascar could not avoid the introduction and spread of the virus. More studies are needed to estimate the true burden of disease and make public health recommendations for a better preparation to another wave.
Plasticity of rosette size in response to nitrogen availability is controlled by an R...
Gustavo Duarte
Prashant Pandey

Gustavo Duarte

and 6 more

January 17, 2021
Nitrogen (N) is fundamental to plant growth, development, and yield. Genes underlying N utilization and assimilation are well characterized, but mechanisms underpinning plasticity of different phenotypes to varying amounts of N in the soil remain elusive. Here, using Arabidopsis thaliana accessions, we dissected the genetic architecture of plasticity in early and late rosette diameter, flowering time and yield in response to three levels of N in soil. Genome-wide association analysis identified three significant associations for phenotypic plasticity, one for early rosette diameter and two for flowering time. We confirmed that the gene At1g19880, hereafter named as PLASTICITY OF ROSETTE TO NITROGEN 1 (PROTON1), encoding for a regulator of chromatin condensation 1 (RCC1) family protein, conferred plasticity of rosette diameter in response to changes in N availability. The altered plasticities were a result of faster development under limiting N, and correlated with the plasticity in the levels of primary metabolites. By using different growth conditions for a subset of accessions, we showed that plasticities of growth and flowering-related traits in response to N availability differed between the environmental cues, indicating decoupled genetic programs regulating these traits. Our findings provide a prospective for identification of genes that stabilize performance under fluctuating environments.
In Vitro Scolicidal Effects of Sideritis perfoliata Aerial Part Extract against the P...
TUNCAY Çelik
Muhittin Önderci

TUNCAY Çelik

and 3 more

January 17, 2021
Background: Cystic echinococcosis (CE) is commonly located in the liver and lungs of affected hosts. Surgical management is one of the best choices for the treatment of hydatidosis and using effective scolicidal agents during hydatid surgery is essential to prevent secondary infection. The present study was designed to investigate the in vitro scolicidal activity of methanol extract of Sideritis perfoliata against the protoscoleces of hydatid cysts. Methods: The protoscoleces were collected from slaughtered livestock in Adiyaman and the effect of three concentrations of the aerial part extract of S. perfoliata (0.1mg/ml, 0.2mg/ml, and 0.4mg/ml) was assessed over three different exposure periods. All tests were carried in dublicate. Finally, the mortality of protoscoleces was assessed by the eosin exclusion test (0.1% eosin staining). Methanol extract of S. perfoliata was assessed by Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS). Results: The results showed that the scolicidal effect of this extract at exposure periods of 10, 20, and 30 min was 29.6, 32.5, and 43.6% at concentrations of 0.1mg/ml, 37.8, 50, and 58.1% at concentration of 0.2mg/ml and finally 57.9, 71.8, and 79.1% at concentration of 0.4mg/ml, respectively; indicating that the extract requiring a further time to display a potent protoscolicidal effects. Some phenolic acids such as fumaric acid (260,13mg/L), syringic acid (27,92mg/L) and caffeic acid (26,84mg/L) and a flavonoid, luteolin (11,23 mg/L) were detected in high concentrations. Conclusions: The present study has demonstrated that the methanol extract of S. perfoliata has high scolicidal power in vitro, although the low concentration of plant extract may provide a base for future treatment of hydatid cysts. However, more research on the in vivo efficacy of S. perfoliata extract and its potential side effects is recommended.
Evaluation of Iron Deficiency in COVID-19 Pneumonia
Ozge Oral Tapan
Canan Gursoy

Ozge Oral Tapan

and 5 more

January 17, 2021
Background: Inlate 2019, a new coronavirus disease was detected in Wuhan, China and called COVID-19. There are so many unknown factors about the virus. Iron metabolism is one of the topics have to be investigated for the development of therapeutic strategies for COVID-19. The aim of this study is to assess sequential changes in traditional biochemical iron status indicators during COVID-19 pneumonia. Methods: A case-control study. Case group was defined as pneumonia with PCR-confirmed SARS-CoV-2 and the control group consisted of patients with non-COVID-19 pneumonia. Biomarkers of anemia and iron metabolism, CRP, procalcitonin were analyzed. Demographic features, CT findings, SpO2, development of ARDS, ICU admission, duration of hospitalization, discharge status (event free survival or death) were evaluated. Results: 205 hospitalized patients with pneumonia were analyzed retrospectively. COVID-19 group was significantly younger than control group. 23 of 106 patients had critical COVID-19 infection. Comorbidity frequency and mortality rate of patients with COVID-19 pneumonia were significantly higher. Hb, RET-He, iron, TSAT, CRP, PCT and SpO2 were significantly lower. Hb, RET-He, iron, TSAT levels significantly correlated to lung aeration loss, hospitalization day and inflamatory markers in COVID-19 pneumonia. Conclusion: The patients with COVID-19 pneumonia had iron deficiency anemia even they were young. Iron deficiency may effect the lung aeration loss related to paranchimal infiltrations of COVID-19 and mortality of the patients with COVID-19 pneumonia. Our data indicates that iron deficiency is associated with longer hospital stays, lower oxygenation, higher CRP and procalsitonin.
SIR epidemiological model with ratio-dependent incidence: influence of preventive vac...
Uday Kumar
PARTHA MANDAL

Uday Kumar

and 4 more

January 17, 2021
In this paper, we study an SIR epidemic model with ratio dependent incident rate function. We explore the impact of vaccination and treatment on the transmission dynamics of the disease. The treatment control strategies depend on the availability of maximal treatment capacity: treatment rate is constant when the number of infected individuals is greater than the maximal capacity of treatment and proportional to the number of infected individuals when the number of infected individuals is less than the maximal capacity of treatment. The existence and stability of the endemic equilibria are governed by the basic reproduction number and treatment control strategies. By carrying out rigorous mathematical analysis and numerical evaluations, it has been shown that (1) the sufficiently large value of the preventive vaccination rate can control the spread of disease, (2) a threshold level of the psychological (or inhibitory) effects in the incidence rate function is enough to decrease the infective population. Model system also undergoes a transcritical and a saddle-node bifurcation with respect to disease contact rate. In the presence of treatment strategies, system have multiple endemic equilibria and undergoes a backward bifurcation. The number of infected individuals decreases with respect to maximal treatment capacity and disease dies out from the system for large capacity of the treatment when constant treatment strategy is applied. Further, it is also found that the spread of disease can be suppressed by increasing treatment rate. Sensitivity analysis shows that the transmission and treatment rates are most sensitive parameters on the model system.
Continuum of one-sign solutions of one-dimensional Minkowski-curvature problem with n...
Yanqiong Lu
Zhengqi Jing

Yanqiong Lu

and 1 more

January 17, 2021
In this work, we investigate the continuum of one-sign solutions of the nonlinear one-dimensional Minkowski-curvature equation $$-\big(u’/\sqrt{1-\kappa u’^2}\big)’=\lambda f(t,u),\ \ t\in(0,1)$$ with nonlinear boundary conditions $u(0)=\lambda g_1(u(0)), u(1)=\lambda g_2(u(1))$ by using unilateral global bifurcation techniques, where $\kappa>0$ is a constant, $\lambda>0$ is a parameter $g_1,g_2:[0,\infty)\to (0,\infty)$ are continuous functions and $f:[0,1]\times[-\frac{1}{\sqrt{\kappa}},\frac{1}{\sqrt{\kappa}}]\to\mathbb{R}$ is a continuous function. We prove the existence and multiplicity of one-sign solutions according to different asymptotic behaviors of nonlinearity near zero.
Some advances on essential spectra of one sided operator matrix with application
Marwa Belghith
Nedra Moalla

Marwa Belghith

and 2 more

January 17, 2021
This paper deals with a new description of the one sided operator matrix form, as a generalization of the case of the unbounded operator matrix with the non diagonal domain, to investigate some advances in the analysis of some essential spectra under weaker hypotheses then the one provided in the works of [17, 33]. An example of differential equations is tested to ensure the validity of the abstract results.
Complete eradication of chronic lymphocytic leukemia with unusual skin involvement of...
Maria Dimou
Theodoros Iliakis

Maria Dimou

and 5 more

January 17, 2021
A 51-year male patient presented with large skin masses of the chest wall that were pathologically proven to be chronic lymphocytic leukemia/small lymphocytic lymphoma(CLL/SLL) with Ki67:70%. The patient was treated with the time-limited Venetoclax/Obinutuzumab combination for 12 cycles and CLL/SLL including the skin component was set in complete remission.
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