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Towards Biogeomorphic River Restoration: Vegetation as a Critical Driver of Physical...
Rossa O'Briain
Dov Corenblit

Rossa O'Briain

and 3 more

November 20, 2023
The current focus of river restoration on flow and sediment transfer without proper consideration of vegetation as a key structuring agent, beyond its stabilising effect, is too simplistic. We contend that vegetation has an essential role in shaping the physical fluvial environment and should be considered equally alongside hydrogeomorphic processes in restoration projects. In support, we introduce engineer plants as important controls, along with flowing water and transported sediments, on the morphodynamics of river systems and associated physical habitat development. The effect of vegetation on channel planform is then summarised, the influence of vegetation on hydrogeomorphic connectivity is outlined, and then the role of vegetation in landform development and habitat provision, as encapsulated in the fluvial biogeomorphic succession model, is described. We then present examples demonstrating how vegetation has contributed to the recovery of degraded rivers through biogeomorphic processes. Finally, we advance the concept of biogeomorphic river restoration by proposing principles to support a closer synthesis of the component sciences and list key areas for practitioners to focus on.
Assessing Motivational Biases in Brain and Behavior: Event-Related Potential and Resp...
Christopher Sege
James Lopez

Christopher Sege

and 3 more

November 20, 2023
The Approach-Avoidance Task (AAT) is designed to 1) measure the implicit motivated action biases that are instantiated by emotional stimuli, and 2) assess the changes in such biases that drive psychiatric disorder. To establish AAT sensitivity to emotional action bias at a neural level, some work has measured event-related potential (ERP) correlates — however, a lack of research with unpleasant, pleasant, and neutral stimuli together and also a common focus on psychiatric disorder-matched (rather than generally evocative) content limits foundational conclusions that can be drawn. In current research, then, 38 subjects completed an AAT where normative (rather than idiosyncratic) unpleasant, pleasant, and neutral images were shown with a color border indicating if a joystick should be rapidly pushed or pulled to decrease or increase image size. Using generally arousing stimuli, response times (RTs) were found to be faster on unpleasant push compared to unpleasant pull trials, t(37)=2.4, p=.02, and 32-sensor electroencephalography (EEG) also revealed that amplitude of a stimulus-response conflict-related ERP – the N200 – was reduced on unpleasant compared to neutral push trials and un-pleasant push compared to unpleasant pull trials, t(32)=5.5, p<.001. In addition, preliminary exploration of individual differences suggested that relevant variables of dimensional trait anxiety, depression, and anxiety disorder treatment seeking status did not impact RT- or N200-indicated emotional biases. Together, then, findings are consistent with a neurobehavioral avoidance bias for unpleasant stimuli while also suggesting a need to further test whether selecting images for idiosyncratic relevance is critical to revealing individual variations in emotional bias.
SUCCESSFUL RAPID LIPOSOMAL AMPHOTERICIN-B DESENSITIZATION IN PEDIATRIC CASE SERIES AN...
Emine Misirlioglu
Cankat Geniş

Emine Misirlioglu

and 5 more

November 20, 2023
Background: Amphotericin B is the broadest-spectrum polyene group antifungal agent. In the presence of an infection caused by a fungal agent resistant to alternative antifungal drugs, desensitization may be the only option to continue treatment. However, there is insufficient information and consensus regarding Amphotericin B desensitization protocols in the pediatric age group. Objective: In this study, we present our experience with five cases where successful desensitization protocols were applied with Liposomal Amphotericin B (AmBisome®; LAMB), along with a review of the literature on pediatric cases. We also provide a sample desensitization protocol that we successfully applied. Methods: In this retrospective study, pediatric patients who continued their treatment with the successful rapid desensitization protocol conducted at the Pediatric Allergy and Immunology Clinic of the Ministry of Health Ankara City Hospital between September 2019 and September 2023 were examined. In our study, desensitization protocols were applied based on Castell et al.’s desensitization protocol. Results: Between 2019 and 2023, five patients aged between 5 and 12 years, including three with hematologic malignancies, one with tuberculosis meningitis, and one with chronic granulomatous disease, were referred to us due to the development of anaphylaxis during their treatment with LAMB. Anaphylaxis is diagnosed clinically, considering the European Academy of Allergy and Clinical Immunology (EAACI). A 16-step desensitization protocol was prepared using LAMB solutions at four different dilutions (0.001 mg/ml, 0.01 mg/ml, 0.1 mg/ml, 1 mg/ml). Each solution consisted of four steps with a 15-minute infusion for each step. Patients was premedicated with 1 mg/kg/dose methylprednisolone and an antihistamine. Conclusion: The data we present on the successful application of a sample protocol to five cases, particularly in a pediatric setting, is a significant and valuable contribution to the field. This can provide important insights and potentially serve as a reference for medical professionals working with similar cases in the future.
Covid-19 Vaccine-Induced (IgG4) Autoimmune Disease: Case Study with Therapeutic and D...
gregory maguire

gregory maguire

November 20, 2023
IntroductionWhether one has been infected with SARS-CoV-2 or had the Covid-19 vaccine, a robust innate and adaptive immune response is elicited. Recent studies provide evidence that the adaptive immune response can persist at high levels for over 6 months after vaccination as measured by sera antibody titers (Doria-Rose et al, 2021). Sera antibody titers against the SARS-CoV-2 virus are significantly higher in the vaccinated compared to those who are infected (Assis et al, 2021; Bartsch et al, 2021). For an unknown number of people, either of these events may lead to autoimmune disease (Guimarães et al, 2015); here called SARS-CoV-2 induced autoimmune disease (Ehrenfeld et al, 2020), and Covid-19 vaccine induced autoimmune disease (Toussirot and Bereau, 2015; Segal and Shoenfeld, 2018). While the two conditions may share similar mechanisms of an impaired, hyper immune response, long Covid may have additional mechanisms such as viral persistence (Wang et al 2020; Neurath et al, 2021). Viral persistence, even at low levels, can lead to a number of consequences, including the release of miRNA packaged into exosomes that induces a pro-inflammatory, Warburg-like effect in surrounding cells (Yoshikawa et al, 2019; Proal and VanElzakker, 2021). Common to both conditions, i.e vaccine induced and Covid-19 induced autoimmunity, susceptibility to infection or severe outcomes may include the effects of previous infections or vaccinations. For example, superantigen-mediated T cell activation can trigger broad B cell activation, and production of autoantibodies against a range of tissues has been shown in multi-inflammatory syndrome (Consiglio et al, 2020), and in patients with acute COVID-19. The spike protein, whether a part of the virion or of the Covid-19 vaccine, contains a superantigenic motif known to elicit a hyperinflammatory adaptive immune response (Cheng et al, 2020). Evidence also finds that the spike protein drives NLRP3 inflammasome activation in human microglia (Albornoz et al, 2022), a possible mechanism in developing neurological symptoms following Covid-19 infection or vaccination. One explanation for this happening is that the virus, or vaccine related proteins, can now target vascular endothelial cells and disseminate to the CNS through a hematogenous mechanism. Once at the blood-brain-barrier (BBB), SARS-CoV-2 or vaccine related protein, binds the zonulin receptor and promotes zonulin release. Then zonulin, via PAR2, induces blood-brain-barrier (BBB) disruption allowing the virus or protein to enter. Disruption of barrier function in epithelial and endothelial cells has been found by UC Berkeley scientists to be mediated by the spike protein alone (Biering et al, 2022), meaning that the spike protein made by mRNA vaccines can mediate this disruption of barrier function. Further, PEG has never been used in an approved vaccine until the mRNA vaccines, and its presence in Pfizer-BioNTech and Moderna-1273 vaccines has raised concerns about possible anaphylactic and fusogenic adverse effects (Sfera et al, 2022). Another concern is that PEG promotes temporary permeabilization of the BBB, a property used by the pharmaceutical industry for drug delivery to the CNS (Rabenel et al, 2020). This may account, in part, for the VAERS-reported neuropsychiatric symptoms, including neurodegenerative disorders (Frontera et al, 2022). Many excipients other than PEG are also used in the mRNA vaccines, and they too may be causative for adverse events (Borgsteede et al, 2021). “Hyper accelerated reviews” of these vaccines by the FDA has been questioned by many scientists, including Dr. Marion Gruber, Ph.D., director of the FDA’s Office of Vaccines Research and Review (Brennan, 2023). In other words, safety and efficacy analysis of mRNA vaccines for Covid-19 have been substandard.Also, chronic activation of the immune system by viral persistence (or vaccine persistence, depending on how long the spike protein is made) can induce autoimmune responses, and molecular mimicry between components of a pathogen and host tissue can lead to specific post-infectious autoimmunity. Structural similarity between human neuronal antigens and SARS-CoV-2 proteins exists. A particular form of autoimmunity described in long COVID is postural orthostatic tachycardia syndrome, a form of autonomic dysregulation that is possibly induced by functional autoantibodies that target G protein–coupled receptors on neurons (Brodin et al, 2022). Another type of autoimmunity relevant to SARS-CoV-2 infection is the production of neutralizing autoantibodies to type I interferons, explaining a sizeable fraction of cases of hypoxemic COVID-19 pneumonia (Bastard et al, 2021). If such neutralizing autoantibodies are present before SARS-CoV-2 infection, due to prior infections or vaccinations, then a patient is clearly at risk of developing severe acute COVID-19 or vaccine induced autoimmune disease. Neutralizing autoantibodies may also appear after SARS-CoV-2 infection, in which case they might instead enable viral persistence, the formation of a viral reservoir and long COVID. That Covid-19 induced autoimmune disease and Covid-19 vaccine induced autoimmune disease share common mechanisms is further evidenced by a recent report that a healthcare professional had her vaccine induced autoimmune disease exacerbated by a breakthrough Covid-19 infection (Staahl, 2022).
Nanoindentation Tip mechanics ascribing bluntness during fracture of thin coatings
A S Bhattacharyya

A S Bhattacharyya

November 20, 2023
Nanoindentation is used for the determination of mechanical properties of thin-coatings comprising a mixture of hard phases. The load-depth plots represent minor fracture (energy ~ pJ) taken place due to assorted crystallization on the surface. The tip movement during the fracture is influenced by strain hardening due to brittle to ductile transformation and the amount of tip-bluntness as evident from the fractorial normal stiffness.
Wake structures and performances of wind turbine rotor with harmonic surging motions...
Wei YU
YuanTso Li

Wei YU

and 2 more

November 19, 2023
Previous numerical studies suggested the motions of Floating Offshore Wind Turbines (FOWTs) may enhance their wake recovery rates due to having different modes of wake dynamics from the bottom-mounted counterparts. However, the majority of previous research were conducted with models having relatively low fidelities and/or focusing on laminar inflow conditions. Models with lower fidelities are not able to capture the dynamics of tip-vorticies reliably while inflow conditions without turbulence are unrealistic out in the fields. In light of this, this paper performed high fidelity numerical simulations (large eddy simulation with actuator line technique) using full scale surging (prescribed and harmonic) FOWT rotor with different inflow turbulence intensities and multiple surging settings systematically to better understand the wake dynamics of FOWT. The results showed that the differences of wake structures between fixed and (harmonic) surging rotors were pronounced when under laminar inflow conditions, where the Surging Induced Periodic Coherent Structures (SIPCS) could be detected straightforwardly; while the differences were much less significant when under inflow conditions with realistic turbulence intensities, and the SIPCS were clearly revealed only after phase-locked averaging. Moreover, when under laminar inflow conditions, the values of mean disk-averaged streamwise velocity at x/D=8 could be above 30% larger for the surging cases than the fixed case, while the increases were down to around 0 .5∼2% when under inflow conditions with realistic turbulence intensities.
Tailoring S-H Binding Strength of a Sulfur-Rich NiS Cocatalyst for Boosting Visible L...
Khakemin Khan
Zia Ur Rehman

Khakemin Khan

and 9 more

November 19, 2023
Transition-metal chalcogenides (MSx) have been shown to be promising low-cost cocatalysts for photocatalytic H2 production. Their performance as cocatalysts, however, is limited due to lack of exposed sulfur (S) sites due to their strong binding with adsorbed atomic hydrogen (S-H). To address this issue, Herein, we demonstrate a unique approach via surface doping of phosphorus (P) atoms into CdS nanorods and fabricated NiS on CdS-P to maintain active site-electron enriched control and electronic structural modification of active S sites. Such a simple nanostructured design exhibits a remarkable improvement in photocatalytic H2 production as 44.39 mmol g-1h-1 under visible light, with an apparent quantum efficiency of 41% at ~ 420 nm. This enhanced photocatalytic hydrogen evolution has been attributable to the modified internal electric field, which accelerates electrons to the surface of NiS for the reduction of hydrogen into H2 instead of adhering to it. Various characterization, such as XPS demonstrate phosphorous doping play a key role in transferring of free electron from CdS to NiS to induce electron-enriched Sδ- active centers resulting in a decrease S-H binding force and boosting photocatalytic hydrogen production. This work describes a broad method for maintaining the number of active sites while tailoring the binding strength between active sites and hydrogen adsorbates.
Theoretical insights into He/CH4 separation by MXene nanopore
Zenan Shi
Shouwei Liao

Zenan Shi

and 3 more

November 19, 2023
Natural gas is currently the main industrial source of helium, thus He/CH4 separation has become increasing important, where two-dimensional materials have been considered to be a potential solution, but the gas transport mechanism within nanopores is not yet clear. Here, both non-equilibrium molecular dynamics (NEMD) and equilibrium MD (EMD) were employed to study the transport of He/CH4 through nanopores of different MXenes with various pore diameters (d), nanopores’ density and functional groups, which shows two main transport mechanisms, molecular sieving or Knudsen diffusion. Small d is found to be crucial for the molecular sieving mechanism and consequently, high He/CH4 selectivity (SHe/CH4). The density profiles of He/CH4 along permeation direction from EMD simulations were used to predict SHe/CH4 and permeance for the gas passing through different nanopores, yielding results well agreeing with NEMD simulations. This work provides theoretical insights into gas transport in MXene nanopore for future nanopore designing engineering.
Optimizing Water Disinfection: A CFD Study on Microorganisms Collision against a Trip...
Leonardo Gadelha Tumajan Costa de Melo
Frederico Duarte de Menezes

Leonardo Gadelha Tumajan Costa de Melo

and 5 more

November 19, 2023
A document by Leonardo Gadelha Tumajan Costa de Melo. Click on the document to view its contents.
Experimental assessment of EAIRMS normalization methodologies for environmental stabl...
Sawyer Balint
Morgan Schwartz

Sawyer Balint

and 5 more

November 19, 2023
RATIONALE: In stable isotope mass spectrometry, isotope values are normalized to internationally recognized reference scales using certified reference materials and working standards. Numerous techniques exist for performing this normalization, but these methodologies need to be experimentally assessed to compare their impact on reproducibility of isotope results. METHODS: We tested normalization methods by the number of standards used, their matrix, their isotope range, and whether normalization required extrapolating beyond the isotope range. Using 8 certified reference materials and 5 working standards on a ThermoFinnigan Delta-V IRMS and Elementar VisION IRMS for nitrogen and carbon isotope composition via solid combustion with an elemental analyzer, we computed every possible isotope normalization (n=6272). Additionally, we assessed how sample matrix impacted linearity effects on both instruments. RESULTS: Normalizations composed of three or four reference materials had better performance than one-point and two-point methods, especially when the normalization was matrix-mixed or extrapolated, and normalizations with an isotope range greater than 15‰ were more accurate under these conditions. Normalizations that were matrix-matched and were not extrapolated exhibited the highest accuracy. Linearity effects were found to exceed instrument precision by two orders of magnitude irrespective of sample matrix and were not predicted by reference gas diagnostics. CONCLUSIONS: To maximize interlaboratory comparability of isotope results, operators of EAIRMS systems should use at least 3 calibration standards to construct their normalizations, select standards with a large isotope range to avoid extrapolation, and match the matrix of their standards to their samples to the best extent possible.
The effect of separate and combined visual evaluation of imaging performed in supine...
Ozan Kandemir

Ozan Kandemir

November 20, 2023
Introduction:99mTc-methoxy-isobutyl-isonitrile myocardial perfusion imaging (99mTc-MIBI MPI), is the most commonly used noninvasive stress imaging method for the diagnosis of coronary artery disease (CAD) (J1). However, despite its overall effectiveness, the interpretation of MPI is complex due to potential imaging artifacts, including those related to the patient and equipment (J). Soft tissue attenuation, such as that caused by breast position or the diaphragm, is one of the most common factors that can reduce the test accuracy for detecting CAD and affect image quality. (G4). To reduce the factors that decrease quality, methods such as electrocardiography-gated imaging, attenuation correction software, and changing the patient’s position have been proposed (G4, G5). MPI is conventionally performed in the supine position (Y). However, different positions are now being used to achieve better imaging quality (G).One approach that has been reported to improve the diagnostic accuracy of MPI is the use of a supine-prone combination rather than supine MPI alone (C).In recent years, numerous studies have shown significant reductions in both diagnostic performance and patient radiation exposure when using ”stress-first” imaging, such that a normal stress study can eliminate the need for subsequent rest imaging (A31, A32, A33, A34). The normal stress study will eliminate the need for subsequent rest imaging, thereby reducing the examination time, radiation dose, and the doses of radiopharmaceuticals used.In cases of diaphragmatic or breast attenuation, the absence of perfusion defects in stress-prone imaging can help exclude ischemic heart disease, especially when combined with a supine study, thereby reducing the need for rest imaging (O).It has been reported that the addition of prone MPI to supine MPI increases the diagnostic accuracy in populations consisting of both women and men (C6, C7, C8). However, data directly comparing these two imaging strategies, especially in cohorts consisting solely of men, are limited (C).Despite its potential to increase diagnostic accuracy, the combined supine-prone MPI is not widely utilized.In our study, we retrospectively investigated the effect of stress supine-only, stress prone-only, and combined stress supine-prone MPS studies on the need for rest imaging in male patients without known coronary artery disease in whom there is limited data in the literature.
Predatory and pseudo-scientific journals: It is not always about monetary gain!
Itamar Ashkenazi

Itamar Ashkenazi

November 27, 2023
Itamar Ashkenazi M.D.Technion – Israel Institute of TechnologyCorresponding author: Itamar AshkenaziFaculty of MedicineTechnion - Israel Institute of TechnologyEfron Street. 1, Haifa, IsraelORCID 0000-0002-6305-4159i_ashkenazi@yahoo.comAuthor contributions – As the sole author of this manuscript, I have contributed substantially to evaluating the data presented (study findings) and manuscript writing. No other individuals were involved in collecting the data and writing the manuscript.Funding declaration – none received.Presentation declaration – The legal aspects with the ethical approval of the experiment previously published by the journal and discussed in this manuscript were presented to the Swedish National Board for Assessment of Research Misconduct (Npof), the Örebro University, the Technion-Israel Institute of Technology, and the Örebro County Board. Preliminary data on the JEVTM statistics, among other journals, was presented in 2022 in meetings on publication ethics held in Portugal and Israel.Conflict of interest statement - The author is acquainted with three of the four researchers of the experiment described in this manuscript (BK, DS, and TH). The author has previously reported other instances of potential research and publication misconduct performed mainly by one of the researchers to the relevant authorities. If it were not for the lenient approach of the relevant authorities, we would likely not be discussing the Journal of Endovascular Resuscitation and Trauma Management’s form of handling scholarly publications since its inaugural issue.Ethics statement – I am the sole author of this manuscript. No other person contributed. Both informed consent and ethical committee approval are irrelevant in this case. This manuscript was first submitted for publication in the Journal of Endovascular Resuscitation and Trauma Management, allowing them to respond to my concerns. However, they opted not to publish it.Data Availability statement - Raw data will be provided by the author (i_ashkenazi@yahoo.com).   
Refractory Hyperkalemia with Hyporeninemic Hypoaldosteronism in Type 2 Diabetes Melli...
Anil Nepali
Prakriti Adhikari

Anil Nepali

and 2 more

November 18, 2023
A document by Anil Nepali. Click on the document to view its contents.
Vulvar Crohn’s Disease Ulcers: A Case Report
Lama  Al-Darwish
Naram   Khalayli

Lama Al-Darwish

and 3 more

November 18, 2023
IntroductionCutaneous manifestations of Crohn’s disease(CD) are classified into reactive, specific, and associated (1).Vulvar CD is rare and associated with intestinal lesions, and skin manifestations, especially pyoderma gangrenosum. It may precede the digestive manifestations of CD in 25% of cases (2).The prevalence of vulvar ulcers in inflammatory bowel disease(VCD) ranges from 0.4% to 2% (1, 3). We report a rare case of VCD in a 32-year-old Syrian female patient.
Electricity pylons are used by olive baboons (Papio anubis) as sleeping sites in Laik...
Laiyon Lenguya
Lolimo Ewaton

Laiyon Lenguya

and 2 more

November 18, 2023
Olive baboons (Papio anubis) use fixed, secure and naturally-occurring sleeping sites such as tall trees and rocky cliffs, as protection from predators. Although these sleeping sites are safe, they can be limited in availability. We documented olive baboons’ use of 45m tall high-tension electrical pylons (towers) as sleeping sites in Laikipia, Kenya. These observations suggest that olive baboons may use anthropic infrastructure for sleeping sites in areas where naturally occurring cliffs and tall trees are limited.
Stricture of esophagus due to ankylosing spondylitis : a case report and literature r...
tianjie han
junshan li

tianjie han

and 1 more

November 18, 2023
A document by tianjie han. Click on the document to view its contents.
Elusive mustelids – 18 months in the search of stoat (Mustela erminea) and weasel (M....
Sofie Nørgaard Konradsen
Linnea Worsøe Havmøller

Sofie Nørgaard Konradsen

and 4 more

November 18, 2023
Stoat (Mustela erminea) and weasel (M. nivalis) are hard to monitor as they are elusive of nature and leave few identifying marks in their surroundings. Stoat and weasel are both fully protected in Denmark and thought to be widely distributed throughout the country. Despite this stoat and weasel were listed on the Danish Red List as Near Threatened in 2019, as their densities and population trends are unknown. Using a modified novel camera trapping device, the Double-Mostela, specifically devel-oped to monitor and individually identify stoat and weasel, we attempted to make density estimates based on identification of individual stoats and weasels. We deployed camera traps both inside Double-Mostela traps and externally in three different study areas in Northern Zealand, Denmark, and tested commercial, American scent-based lures to attract stoat and weasel. We obtained trapping rates of 0.03 and 0.06 weasel per 100 camera trap days and 0.45 and 1.26 stoats per 100 camera trap days in two of the study areas, respectively. This is low compared to other countries and in one study area both species were absent. We found no effect of scent-based lures in attracting small mustelids com-pared to non-bait traps. Potential reasons behind low capture rates of weasel and stoat are land use changes over the last 200 years, predation from larger predators, birds of prey and free-roaming, domestic cats as well as unintended secondary poisoning with rodenticides. Due to the scarcity of weasel and stoat captures, we were unable to make density estimates based on identification of individuals, however, we identified potential features that could be used for identification and density estimates with more captures.
Cryptogenic Stroke in an Adult Sudanese Female with Interatrial Septal Aneurysm: A Ca...
Mahmoud  Salih Daoud
Ejlal Ahmed.E. Abushama

Mahmoud Salih Daoud

and 15 more

June 07, 2022
Cryptogenic Stroke in an Adult Sudanese Female with Interatrial Septal Aneurysm: A Case ReportMahmoud Hussien Salih Daoud1, Ejlal Ahmed.E. Abushama2, Abdallah H. Mahmmoud3, Mohammed Mahmmoud Fadelallah Eljack4, Khabab Abbasher Hussien Mohamed Ahmed5, Mazin S. Hassan Haroun6, Elfatih A. Hasabo7, Duaa Baderaldeen Ibraheem Elsheikh8, Sulieman Abdelkareim G. Mohammed9, Ahmed Eltayeb O. Eltayeb10, Yusif Abduelmagid M. Naimallah11, Alameen Ahmed Alameen Ahmed12, Mohamed Yusif Mohamed Yusif13, Asmaa Esam Abbas Mokhtar14, Sara Nasreldeen Ibrahim Awadalbari15, Rowida Babikir Osman Eltayeb16
Possible pathogenesis clue of Takotsubo syndrome: a case report.
Cunxue Pan
Mei Xu

Cunxue Pan

and 7 more

November 18, 2023
Possible Pathogenesis Clue of Takotsubo syndrome: a case report.
leiomyoma beyond uterus
Indhu S
Mohan Raj

Indhu S

and 2 more

November 18, 2023
Title :Leiomyoma beyond the uterus
ShabdSur: App that Transforms Documents into multilingual Audiobooks
Hamza Khan

Hamza Khan

November 20, 2023
A document by Hamza Khan. Click on the document to view its contents.
Simultaneous occurrence of transient global amnesia and takotsubo syndrome triggered...
Claudia Stöllberger
J Finsterer

Claudia Stoellberger

and 1 more

November 18, 2023
Simultaneous occurrence of transient global amnesia and takotsubo syndrome triggered by caring for a terminally ill relative
Letter To the Editor
Elahe Abbaspour
Sahand Karimzadhagh

Elahe Abbaspour

and 1 more

November 18, 2023
Letter To the EditorWe read the article ”Retroperitoneal Schwannoma: Uncommon Location of a Benign Tumor” by Debaibi et al. 1 in the Journal of Clinical Case Reports in 2022 with great interest. While this research is undoubtedly valuable in contributing to our understanding of retroperitoneal schwannomas, it has come to our attention that certain aspects of the study merit further discussion and consideration.In the opening paragraph of the discussion section, the authors allude to the rarity of malignant transformation within schwannomas, except in cases of type 2 neurofibromatosis, citing Harhar et al. 20212. However, this statement is inaccurate, as Harhar et al. reported that up to 60% of individuals with Von Recklinghausen’s disease, specifically referring to neurofibromatosis type one, may undergo malignant transformation. Therefore, the assertion concerning type 2 neurofibromatosis lacks support from their reference. For the sake of clarity, farschtchi et al.3, in their article, also stated that “schwannomas in neurofibromatosis type 2 hardly ever undergo malignant transformation.”In the second paragraph of the discussion section, the authors refer to abdominal Magnetic Resonance Imaging (MRI) as the ”gold standard” for diagnosis, citing Radojkovic et al. 4 and Harhar et al. While Radojkovic et al. do emphasize the role of MRI in diagnosing soft-tissue tumors, it is crucial to clarify that MRI is not universally the gold standard for differentiating between benign and malignant lesions. Moreover, Harhar et al. acknowledge the lack of distinct imaging characteristics for retroperitoneal schwannomas on computed tomography (CT) and MRI scans. Since there is no gold standard diagnostic method for RSs5, establishing a definitive preoperative diagnosis of RSs remains challenging. However, the importance of contrast-enhanced CT as a primary imaging investigation, especially in differentiating various pathologies in the retroperitoneum, should be highlighted, as suggested by Messiou et al.6 in 2018. Despite the availability of numerous advanced imaging techniques, such as ultrasound (US), CT, and MRI, the absence of distinct imaging features limits our ability to diagnose RSs accurately, with less than 20% of all cases receiving a precise preoperative identification. 7Lastly, in the introduction section, the authors state that retroperitoneal schwannomas represent only 4% of all retroperitoneal tumors, citing Radojkovic et al. 2018. 4 However, I would like to point out that this specific reference is not mentioned anywhere in the manuscript. The accurate source for this information is Harhar et al. 2021. This discrepancy in referencing should be addressed and corrected, as the integrity of scientific literature relies on accurate and well-referenced information, especially in clinical case reports.Retroperitoneal schwannomas (RSs) are unusual tumors, accounting for only 1 to 3% of all schwannomas. They often go unnoticed due to the expansive and flexible nature of the retroperitoneal space, leading to delayed diagnosis and significant lesion growth. Definitive diagnosis of schwannomas is based on histopathological and immunohistochemical findings8. Characteristic histopathological changes are marked by elongated spindle cells forming hypercellular Antoni A areas with twisted nuclei and Verocay bodies, as well as hypocellular Antoni B regions exhibiting inflammatory cells, collagen bundles, and xanthomatous changes8,9. The primary treatment approach involves surgical removal, which can be accomplished through traditional open procedures or minimally invasive laparoscopy, often yielding positive therapeutic results5,10. However, this necessitates thorough preoperative planning and a multidisciplinary approach, given the complex nature of both diagnosis and treatment.
Hemoptysis secondary to Anomalous Origin of Right Pulmonary Artery from ascending aor...
Simran Nimal
Gowrishankar Palaniswamy

Simran Nimal

and 7 more

November 18, 2023
Title: Hemoptysis Secondary to Anomalous Origin of Right Pulmonary Artery from Ascending Aorta in a Young Male: A Case Report
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