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Mohammad El Tahlawi

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Background: Congenital pulmonary stenosis (PS) is a progressive disease. Balloon pulmonary valvuloplasty (BPV) is the treatment of choice in valvular PS. Aim: We aim to study the relationship between biomarkers and echocardiographic markers in valvular PS and to assess the impact of BPV on these markers. Patients & Methods Patients with moderate and severe valvular PS amenable for BPV were recruited. Serum troponin I was measured. Echocardiographic assessment of PS and right ventricular (RV)function were done. All patients underwent BPV. Troponin level and echocardiographic data were re-assessed two weeks & six months after BPV. Results: Fifty patients with valvular PS were recruited. There was significant correlation between peak SPG and troponin (p < 0.001). Troponin was significantly decreased 2 weeks after BPV. Similarly, there was an initial improvement in RV function. After 6 months of follow up, we divided patients into 2 groups: Group-A: 36 patients with no restenosis. Group-B: 14 patients with restenosis. There were high significant differences between both groups regarding troponin level and RV functions with re-elevated troponin in group-B that correlated with peak PG (r= 0.9, p < 0.001). RV function parameters in group-B became significantly worse 6 months after BPV than those after the initial 2 weeks. Conclusion Troponin correlates with the severity of PS and associates with RV dysfunction. Both troponin & RV functions improved with BPV. Recurrent elevation of troponin and impairment of RV function are associated with PV restenosis and could be set as an indication for repeated balloon dilatation of PV.

Brian Kirsch

and 9 more

Noredin Rostami

and 3 more

Wind erosion is one of the desertification results and is among the natural processes that mostly occur under dry conditions and high wind velocity. Using oil-mulches is one of the common methods to stabilize sand dunes. The current study aimed to investigate the short-term effects of oil-mulch on vegetation attributes (i.e., cover and diversity) and rangeland condition score (RCS) using integrated ecological and remote sensing-based approaches in arid regions of Southwestern Iran. A vegetation survey was carried out in 2019 in the oil-mulched and control area, and a remotely sensed vegetation index (MSAVI) was calculated for 2017 and 2019. The results indicate that one year after treatment, compared to the control area, vegetation cover (30 ± 17.11 vs. 17 ± 5.44 %) and litter (4.6 ± 2.18 vs. 0.94 ± 1.55 %) increased significantly in the oil-mulched area, while bare soil (65.20 ± 17.34 vs. 82.31 ± 5.84 %) decreased. Further, diversity indices (Species evenness, Shannon, and Simpson indices) declined by applying oil-mulch (88%, 63%, and 71%, respectively). The rangeland condition score was significantly higher in the oil-mulched area than in the control area (22 ± 1.86 vs. 12 ± 0.88; P < 0.001). Comparing MSAVI between 2017 and 2019 showed that vegetation cover increased 44.8%. Based on the results, it can be suggested that planting native palatable species in an oil-mulched area with the exclusion of livestock grazing is likely to increase the benefits of oil-mulch treatment and will lead to better rangeland condition score.

Filiz Özdemir

and 1 more

Background: Hippotherapy is recognized as an integrative therapy in rehabilitation programs as it provides a basis for neurological function and sensory processing. The aim of this study is to evaluate the effects of hippotherapy on posture and trunk control in children with spastic diplegic cerebral palsy. Materials and Methods: This study which a pre-test/post-test quasi experimental model with a control group was included 24 participants aged 7-12 years. In addition to routine physiotherapy and rehabilitation program for participants in experimental group, hippotherapy training sessions lasting 30 minutes were given once a week for 12 weeks each, under the direction of a physiotherapist. Postural alignment changes were evaluated by using New York Posture Rating Chart (NYPR). Trunk Impairment Scale (TIS) was used to evaluate trunk control. Results: The mean age was 13.62 ± 3.17 years. Mean body mass index (BMI) was 23.34 ± 3.38 kg / m2. There was no statistically significant difference between groups in terms of age, gender, BMI, and GMFCS (p> 0.05 for all). There was no difference in NYPR results between the groups (p> 0.05). Total TIS score and static sub-parameter scores were higher in experimental group, after the treatment (p <0.05), whereas there was no difference in terms of dynamic and coordination sub-parameters. Conclusions: We concluded that hippotherapy is a viable treatment strategy to obtain functional results in children with spastic diplegic cerebral palsy. However, we emphasize that effectiveness of hippotherapy in different age groups should be investigated with larger sample groups.

Basant Yadav

and 9 more

In semi-arid and arid regions, groundwater is the primary source for domestic, agricultural, and industrial supply. Scattered and erratic rainfall in these regions makes groundwater recharge more complex. Small-scale rainwater harvesting using both traditional and modern rainwater harvesting structures has been seen as a solution to the deepening groundwater crisis in India. In this study, shallow infiltration ponds locally known as Chaukas were studied to understand their groundwater recharge role and pastureland development. Potential groundwater recharge from these shallow infiltration ponds was estimated using the HYDRUS-1D model, simulating the sub-surface processes in the root zone. Field data collected in the year 2019 is used to calibrate the model for field conditions, while monsoon period data (July-August) of 2020 is used to validate the developed model. The developed model was then used to predict the potential groundwater recharge for the monsoon periods of the year 2019 and 2020.The shallow infiltration ponds allow approximately 5% additional rainfall to be available as potential recharge. The near soil surface moisture also helps develop natural grass cover used for pasture in the early dry periods. Analysis of the vegetation in the past 10 years suggests that these shallow infiltration ponds have converted barren lands into eco-hydrologically productive pasturelands. These Chauka systems have helped in sustainable water resources management in these water stressed regions along with the additional livelihood support through developed pasturelands for animal husbandry. They have potential wide application across India and beyond, as they simply require slightly sloping, barren land above an unconfined aquifer.

Yihan Li

and 4 more

Changbai Mountain is the source region of Songhua River, Tumen River and Yalu River. It is a famous concentrated distribution area of high quality mineral water in China, which has great economic value. Antu County is one of the main distribution areas of basalt and mineral water in Changbai Mountain. The distribution of mineral springs has a strong hydraulic relationship with surface water, which constitutes abundant recharge reserves. It is necessary to study the hydrochemical characteristics and relationship between surface water and mineral water, so as to provide a theoretical basis for further discussion on the formation process and rational utilization of mineral water resources in Changbai Mountain. 57 water samples from 2016 to 2020 were collected, including precipitation, mineral water and surface water. Geostatistics, Piper and Gibbs diagram are used to analyze the hydrochemical characteristics. Hydrochemical component tracing and stable environment isotope technology with end-number calculation are used to reveal the transformation relationship between mineral water and surface water. Results demonstrate: Surface water and mineral water are weak alkaline and low salinity. The hydrochemical type of mineral water is mainly HCO3-Na·Mg·Ca and of surface water is mainly HCO3-Na. The isotopes of precipitation are more enriched in summer due to the influence of water vapor source and temperature effect. The temporal and spatial differences between D and 18O of mineral water is obvious, and isotopes are enriched abundant in autumn. The recharge source and interaction between mineral water and surface water have changes in different periods. In summer, mineral springs in Erdaobai River and Sandaobai River watershed replenished surface water, and the recharge proportion is more than 60%. The interaction between Toudao Baihe river and mineral water is weak. In autumn, precipitation is the main recharge for mineral water and surface water.

Xiaodong Tang

and 1 more

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Oktay Ucer

and 3 more

Semih Ak

and 1 more

Background: Hookah is a tobacco product of Middle Eastern origin; however, its popularity increases in Europe and the US. Despite its frequent use, hookah’s potentially detrimental effects are underestimated due to the scarcity of the relevant research. Since septoplasty is one of the most commonly performed procedures of otolaryngology practice, we aimed to investigate the impact of hookah consumption on recovery after septoplasty. Methods: Patients who underwent septoplasty in Sanliurfa Training and Research Hospital Department of Otolaryngology between January 2017 and December 2019 were divided into four groups based on their history of hookah and cigarette smoking. The patients’ prospectively collected data, including demographic features, healing time, and presence or absence of septal perforation during follow-up, were compared between these four groups. Results: The entire cohort included 270 patients. The mean patient age was 29.2±5.8 years. One hundred and thirty-two (48.9%) patients were non-smokers, 96 (35.5%) were cigarette smokers, 27 (10%) were hookah smokers, and 15 (5.6%) consumed both tobacco products regularly. Mean healing time was 10 days, and septal perforation was encountered in 10 patients (3.7%). A comparison of the groups revealed that cigarette smoking did not impact septal perforation rates (p=0.326) but prolonged the healing time. However, hookah smoking with or without cigarette smoking significantly influenced septal perforation rates and healing times. Conclusion: Patients should be questioned about hookah smoking in addition to cigarette smoking before the septoplasty procedure. Patients with a positive history of hookah smoking should be followed closely in terms of delayed healing and increased septal perforation rates.

George Angelidis

and 3 more

COVID-19 and nuclear cardiology: Introducing the ‘’forward” virtual visit Angelidis G, Valotassiou V, Psimadas D, Georgoulias PNuclear Medicine Laboratory, University of Thessaly, Larissa, GreeceWe read with great interest the recent review article by Kaushik A, et al. concerning the potential role of digital health applications in the present pandemic situation [1]. As the authors noted, alternative tools are needed for the optimal management of cardiovascular patients, avoiding unnecessary visits to health care facilities. The severe acute respiratory syndrome – coronavirus – 2 (SARS-CoV-2) can invade the cardiovascular cells, potentially causing life-threatening cardiac impairment [2]. In particular, patients with pre-existing cardiovascular diseases are characterized by a higher risk of adverse cardiovascular events. Therefore, most of those referred for nuclear cardiology techniques are expected to be at higher risk of developing serious coronavirus disease 2019 (COVID-19) complications. However, the performance of the individually required diagnostic and follow-up procedures is important [3].Telemedicine applications have been used in public health emergencies, leading to several advantages in terms of safety and efficacy. In the field of nuclear cardiology, the initial evaluation of patients’ history and clinical features can take place remotely (‘’forward” virtual visit). This approach seems to be patient-centred (permitting an adequate case assessment) and conducive to self-quarantine (protecting patients, healthcare professionals, and the community from viral exposure). Importantly, possible clinical presentations of COVID-19 may be evaluated during the ‘’forward” virtual visit, as well as information regarding travel and exposure histories. Moreover, local epidemiological information may be used to adjust screening pattern, and special measures could be developed (such as isolation in dedicated ‘’hot” rooms) for patients with high-risk features. After the performance of the examination, telemedicine applications could be also used for the consultation with the patients.Telemedicine applications may contribute to a better adjustment of nuclear cardiology services under the current demanding circumstances. Of course, no telemedicine programme can be created overnight, but this approach may be of value not only during the next months but also after the end of COVID-19 pandemic [4]. For example, our nuclear medicine laboratory is located in central Greece providing services to inhabitants of mountain villages, and nearby small islands. Consequently, the use of telemedicine applications could aid our practice in the future as well, particularly during the winter months when travelling by car or sea travels may be extremely demanding.

Attila Mokánszki

and 8 more

Background Retinoblastoma (Rb) is a malignant tumor of the developing retina that affects children before the age of five years in association with inherited or early germline mutations of the RB1 gene. The genetic predisposition is also related with second primary malignancies arising de novo, or following radiotherapy which have become the leading cause of death in retinoblastoma survivors. Procedure We describe a retinoblastoma case with a novel RB1 and a synchronous MET aberration. Our goal was to identify all germline and somatic genetic alterations in available tissue samples from different time periods and to reconstruct their clonal relations using next generation sequencing (NGS). We also used structural and functional prediction of the mutant RB and MET proteins to find interactions between the defected proteins with potential causative role in the development of this uniqe form of retinoblastoma. Results In this study we detected a retinoblastoma case of non-parental origin with a novel RB1 c.2548C>T;p.(Gln850Ter) and a synchronous MET c.3029C>T;p.(Thr1010Ile) germline mutations. Following bilateral retinoblastoma the boy further developed at least four different manifestations of two independent osteosarcomas. Both histopathology and NGS findings supported the independent nature of a chondroblastic osteosarcoma of the irradiated facial bone followed by an osteoblastic sarcoma of the leg (tibia). Conclusions Because of the expanding number of registered Rb cases, the novel rare cases publication is very important to understand the molecular mechanism of this malignancy. We reported a novel form of Rb and consequential chondroblastic and osteoblastic osteosarcoma, the latter one developing pulmonary metastatses.

Ugur Balkanci

and 2 more

An Unusual Case of Necrotizing Pneumonia Presenting with Acute Kidney InjuryUgur Berkay Balkanci, MDSchool of Public Health, University of Minnesota, Minneapolis, MNDavid J. Sas, DODivision of Pediatric Nephrology and Hypertension, Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, MinnesotaNadir Demirel, MDDivision of Pediatric Pulmonology, Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, MinnesotaCorresponding Author:Nadir Demirel, MDDivision of Pediatric Pulmonology200 First Street SWRochester, MN 55906Tel. No.: 5075380754Fax No.: 5072840727Demirel.nadir@mayo.eduKey words: postinfectious glomerulonephritis, pneumothorax, complications, complicated pneumoniaFinancial Disclosure: The authors have indicated they have no financial relationships relevant to this article to disclose.Funding: No external funding.Short title: “An unusual case of necrotizing pneumonia”To the Editor:Lower respiratory tract infections are the most common reason for hospitalization in the pediatric age group in the United States. Although pneumonia is prevalent, complicated pneumonia such as empyema, lung abscess and necrotizing pneumonia (NP) is uncommon in children1. The prevalence of complicated pneumococcal pneumonia decreased significantly after the introduction of the thirteen-valent pneumococcal vaccine in 20101. NP in the pediatric population is a severe disease characterized by extensive destruction and liquefaction of the lung tissue resulting in loss of the pulmonary parenchymal architecture, cavitation of the lung, and pleural involvement. Renal complications of complicated pneumonia are rare and mostly reported as atypical hemolytic uremic syndrome (HUS)2. Post-infectious glomerulonephritis (PIGN) is an unexpected complication of bacterial pneumonia3.We report a six-year-old otherwise healthy fully vaccinated girl with a 4-day history of fever, abdominal pain, vomiting, non-bloody diarrhea, and poor oral intake. Parents reported decreased urine output and dark-colored urine on the day of admission. Initial evaluation revealed serum creatinine of 5.01 mg/dL and blood urea nitrogen of 86 mg/dL, elevated acute phase reactants suggesting acute kidney injury (AKI) in the setting of an undiagnosed acute infectious process. The patient was admitted with decreased effective circulatory volume. Urinalysis revealed hematuria with <25% dysmorphic red blood cells (RBCs), proteinuria, pyuria, and RBC casts and granular casts, suggestive of acute glomerulonephritis.She was started on intermittent hemodialysis at day 2 of admission to address uremia, fluid overload, and hyperphosphatemia. A renal biopsy revealed diffuse exudative glomerulonephritis, consistent with infection-related glomerulonephritis. ASO, Anti-DNase B were negative; C3, C4 levels were low. She was treated with pulse IV methylprednisolone 10mg/kg/day for three days. The first 5 days in the hospital, the patient remained afebrile and her lung exam was normal without respiratory symptoms.On day six of admission, she developed acute right-sided chest pain and shortness of breath during hemodialysis. Chest x-ray (CXR) revealed a large right-sided tension pneumothorax, prompting therapeutic chest tube placement. Repeat CXR revealed reexpansion of the right lung and a significant right upper lobe consolidation with an ovoid hyperlucency and an air-fluid level. A chest CT scan confirmed the diagnosis of NP with multiple cavities (Image).Flexible bronchoscopy was performed with bronchoalveolar lavage revealing 42% neutrophils and negative cultures. She was treated with broad spectrum intravenous antibiotics.During admission, she developed hypertension, well-controlled with scheduled enalapril and amlodipine, as well as isradipine as needed. On day 14 of admission, hemodialysis was discontinued as kidney function improved, and chest tube was removed. She was discharged at day 26 of admission on intravenous ceftriaxone and oral metronidazole to complete 30 days of treatment. A repeat chest CT at end of treatment showed complete resolution of NP. Renal functions and blood pressure normalized on follow up.NP is characterized by persistent high fevers and prolonged hospitalizations even with appropriate antibiotic treatment1. Most often, NP affects immunocompetent children with no underlying risk factors4. The pathophysiology of this complication is acute liquefactive necrosis of the lung parenchyma which results in the development of pneumatoceles4. The most common pathogen causing NP is Streptococcus pneumoniae followed by Staphylococcus aureus and Streptococcus pyogenes. Other rarer bacterial and viral pathogens are Mycoplasma pneumonia, Influenza, and Adenovirus1. Identifying the microbiologic pathogen can be challenging and is only made in 50% of cases1. In our case, we did not isolate the causative microorganism. NP typically resolves without residual morbidity, even after a protracted course1,4.Pleural involvement is almost universal in NP, and the course of pleural disease often determines duration and outcome, particularly as it relates to the complication of bronchopleural fistula (BPF)1. BPF is most likely due to the necrotic development of a connection between bronchial space and pleural space4. BPF formation is associated with a significantly longer hospital stay in children with NP4. Yet, most cases heal without surgical intervention4. Tension pneumothorax has been observed as a rare complication of NP1.Renal involvement in complicated pneumonia is rare. Atypical HUS has been reported as a complication of pneumonia, particularly associated with empyema. (most commonly due to invasive Streptococcus pneumoniae)2. In a case series of 37 cases of atypical HUS, 34 patients (92%) had pneumonia with 10 patients (29%) with NP5. Less commonly, pneumonia can be associated with PIGN. PIGN is the most common glomerulonephritis in children worldwide. Pneumonia-associated PIGN is rare. In a case series from the US, PIGN accounted for 0.15% of admissions for pneumonia and 0.39% of admissions for glomerulonephritis6. Pneumonia-associated PIGN is known to be caused by various bacterial pathogens including Streptococcus pneumoniae, Staphylococcus aureus, Mycoplasma pneumoniae, Chlamydia pneumoniae, Nocardia, and Coxiella burnetii3. Different from the usual presentation of the PIGN (in which the time interval between a pharyngeal group A Streptococcal infection and PIGN is 6 to 10 days), pneumonia-associated PIGN is usually concomitant with the pulmonary disease3,6.Our case is unusual in several ways: pneumonia-associated PIGN typically presents with respiratory symptoms first, and acute kidney injury developing during the course of pneumonia3. More surprisingly, the patient developed NP which is characterized by even more severe respiratory symptoms1. Yet, our patient presented without respiratory complaints and pneumonia became apparent only after the development of pneumothorax. We could only identify 2 cases of pneumonia-associated PIGN who presented with renal involvement before pulmonary complaints6,7. Also, previous cases in the literature of pneumonia-associated PIGN report mostly a non-complicated course of pulmonary disease3,6. In a case series of 11 children with pneumonia-associated PIGN, only one case developed a small empyema6. Similarly, the majority of the reported cases of pneumonia-associated PIGN describe a benign course of renal disease3,6. Our patient’s kidney failure progressed rapidly, and she required 2 weeks of intermittent hemodialysis and a three-day course of pulse steroid therapy. At present, systemic corticosteroids are not recommended for patients with complicated pneumonia. A Cochrane review including 17 randomized controlled trials, of which four were conducted on children, found that corticosteroid therapy reduced mortality and morbidity in adults with severe CAP, and morbidity, but not mortality, in adults and children with non-severe CAP1. We speculate that pulse steroid treatment may have modified the course of NP in our patient.This case suggests an atypical presentation of NP with predominant renal complications is possible. Pediatricians should be aware of renal complications of respiratory diseases. Systemic steroids should be considered in the treatment of NP.References:1. de Benedictis FM, Kerem E, Chang AB, Colin AA, Zar HJ, Bush A. Complicated pneumonia in children. Lancet 2020;396:786-798.2. Spinale JM, Ruebner RL, Kaplan BS, Copelovitch L. Update on Streptococcus pneumoniae associated hemolytic uremic syndrome. Curr Opin Pediatr 2013;25:203-208.3. Carceller Lechón F, de la Torre Espí M, Porto Abal R, Écija Peiró JL. Acute glomerulonephritis associated with pneumonia: a review of three cases. Pediatr Nephrol 2010;25:161-164.4. Sawicki GS, Lu FL, Valim C, Cleveland RH, Colin AA. Necrotising pneumonia is an increasingly detected complication of pneumonia in children. Eur Respir J 2008;31:1285-1291.5. Banerjee R, Hersh AL, Newland J, Beekmann SE, Polgreen PM, Bender J, Shaw J, Copelovitch L, Kaplan BS, Shah SS. Streptococcus pneumoniae-associated Hemolytic Uremic Syndrome Among Children in North America. Pediatr Infect Dis J 2011;30:736-739.6. Srivastava T, Warady BA, Alon US. Pneumonia-associated acute glomerulonephritis. Clin Nephrol 2002;57:175-182.7. Schachter J, Pomeranz A, Berger I, Wolach B. Acute glomerulonephritis secondary to lobar pneumonia. Int J Pediatr Nephrol 1987;8:211-214.

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