Intrafractional motion detection for spine SBRT via X-ray imaging using ExacTrac Dynamic.

Purpose: Due to its close vicinity to critical structures, especially the spinal cord, standards for safety for spine stereotactic body radiotherapy (SBRT) should be high. This study was conducted, to evaluate intrafractional motion during spine SBRT for patients without individualized immobilization (e.g., vacuum cushions) using high accuracy patient monitoring via orthogonal X-ray imaging. Methods: Intrafractional X-ray data were collected from 29 patients receiving 79 fractions of spine SBRT. No individualized immobilization devices were used during the treatment. Intrafractional motion was monitored using the ExacTrac Dynamic (ETD) System (Brainlab AG, Munich, Germany). Deviations were detected in six degrees of freedom (6 DOF). Tolerances for repositioning were 0.7 mm for translational and 0.5° for rotational deviations. Patients were repositioned when the tolerance levels were exceeded. Results: Out of the 925 pairs of stereoscopic X-ray images examined, 138 (15 %) showed at least one deviation exceeding the predefined tolerance values. In all 6 DOF together, a total of 191 deviations out of tolerance were recorded. The frequency of deviations exceeding the tolerance levels varied among patients but occurred in all but one patient. Deviations out of tolerance could be seen in all 6 DOF. Maximum translational deviations were 2.6 mm, 2.3 mm and 2.8 mm in the lateral, longitudinal and vertical direction. Maximum rotational deviations were 1.8°, 2.6° and 1.6° for pitch, roll and yaw, respectively. Translational deviations were more frequent than rotational ones, and frequency and magnitude of deviations showed an inverse correlation. Conclusion: Intrafractional motion detection and patient repositioning during spine SBRT using X-ray imaging via the ETD System can lead to improved safety during the application of high BED in critical locations. When using intrafractional imaging with low thresholds for re-positioning individualized immobilization devices (e.g. vacuum cushions) may be omitted.

The role of online MR-guided multi-fraction stereotactic ablative radiotherapy in lung tumours.

Background: The aim of this prospective observational study was to evaluate the dosimetry benefits, changes in pulmonary function, and clinical outcome of online adaptive MR-guided SBRT. Methods: From 11/2020-07/2022, 45 consecutive patients with 59 lesions underwent multi-fraction SBRT (3-8 fractions) at our institution. Patients were eligible if they had biopsy-proven NSCLC or lung cancer/metastases diagnosed via clinical imaging. Endpoints were local control (LC) and overall survival (OS). We evaluated PTV/GTV dose coverage, organs at risk exposure, and changes in pulmonary function (PF). Acute toxicity was classified per the National Cancer Institute-Common Terminology Criteria for Adverse Events version 5.0. Results: The median PTV was 14.4 cm3 (range: 3.4 - 96.5 cm3). In total 195/215 (91%) plans were reoptimised. In the reoptimised vs. predicted plans, PTV coverage by the prescribed dose increased in 94.6% of all fractions with a median increase in PTV VPD of 5.6% (range: -1.8 - 44.6%, p < 0.001), increasing the number of fractions with PTV VPD ≥ 95% from 33% to 98%. The PTV D95% and D98% (BED10) increased in 93% and 95% of all fractions with a median increase of 7.7% (p < 0.001) and 10.6% (p < 0.001). The PTV D95% (BED10) increased by a mean of 9.6 Gy (SD: 10.3 Gy, p < 0.001). At a median follow-up of 21.4 months (95% CI: 12.3-27.0 months), 1- and 2-year LC rates were 94.8% (95% CI: 87.6 - 100.0%) and 91.1% (95% CI: 81.3 - 100%); 1- and 2-year OS rates were 85.6% (95% CI: 75.0 - 96.3%) and 67.1 % (95% CI: 50.3 - 83.8%). One grade ≥ 3 toxicity and no significant reduction in short-term PF parameters were recorded. Conclusions: Online adaptive MR-guided SBRT is an effective, safe and generally well tolerated treatment option for lung tumours achieving encouraging local control rates with significantly improved target volume coverage.

Proteome profiling of enriched membrane-associated proteins unraveled a novel sophorose and cello-oligosaccharide transporter in Trichoderma reesei.

BACKGROUND: Trichoderma reesei is an organism extensively used in the bioethanol industry, owing to its capability to produce enzymes capable of breaking down holocellulose into simple sugars. The uptake of carbohydrates generated from cellulose breakdown is crucial to induce the signaling cascade that triggers cellulase production. However, the sugar transporters involved in this process in T. reesei remain poorly identified and characterized. RESULTS: To address this gap, this study used temporal membrane proteomics analysis to identify five known and nine putative sugar transporters that may be involved in cellulose degradation by T. reesei. Docking analysis pointed out potential ligands for the putative sugar transporter Tr44175. Further functional validation of this transporter was carried out in Saccharomyces cerevisiae. The results showed that Tr44175 transports a variety of sugar molecules, including cellobiose, cellotriose, cellotetraose, and sophorose. CONCLUSION: This study has unveiled a transporter Tr44175 capable of transporting cellobiose, cellotriose, cellotetraose, and sophorose. Our study represents the first inventory of T. reesei sugar transportome once exposed to cellulose, offering promising potential targets for strain engineering in the context of bioethanol production.

Mind the Gap: A Questionnaire on the Distance between Diagnostic Advances and Clinical Practice in Skin Cancer Treatment.

Background and Objectives: Significant progress has been made in skin cancer diagnosis, with a surge in available technologies in recent years. Despite this, the practical application and integration of these technologies in dermatology and plastic surgery remain uneven. Materials and Methods: A comprehensive 20-question survey was designed and distributed using online survey administration software (Google Forms, 2018, Google, Mountain View, CA, USA) from June 2023 to September 2023. The survey aimed to assess the knowledge and utilization of dermatologic diagnostic advancements among plastic surgeons in various European countries. Results: Data were obtained from 29 plastic surgeons across nine European countries, revealing a notable gap between diagnostic technologies and their routine use in surgical practice. The gap for some technologies was both cognitive and applicative; for electrical impedance spectroscopy (EIS) and multispectral imaging, only 6.9% of the sample knew of the technologies and no surgeons in the sample used them. In the case of other technologies, such as high-frequency ultrasound (HFUS), 72.4% of the sample knew about them but only 34.5% used them, highlighting a more significant application problem. Conclusions: Spotlighting this discrepancy provides a valuable foundation for initiating collaborative efforts between units and facilitating knowledge exchange among diverse specialists. This, in turn, contributes to advancing clinical practice by integrating the innovative opportunities presented by ongoing research.

Continuity of care for patients recovering from Covid-19 under the angle of clinical management principles.

OBJECTIVE: To analyze the strategies used by nurses at a university hospital to ensure continuity of care at hospital discharge for patients recovered from Covid-19, under the angle of the principles of clinical management. METHOD: A descriptive study with a qualitative approach, carried out with seven nurses on duty in the medical and gynecology/obstetrics clinics of a university hospital in the Midwest region of the country. The data was processed using IRaMuTeQ software and analyzed using Content Analysis. RESULTS: The data resulted in five classes by the Descending Hierarchical Classification (DHC), which made up two categories: "Practices developed by nurses for continuity of care in the hospital environment" and "Continuity of care during discharge to the home". The strategies used by the nurses were: daily care systematized in the nursing process and guidance both for preparation and for the day of discharge. CONCLUSION: The absence of an institutional protocol for safe discharge, as well as the position of nurse coordinator to manage the discharge of patients with Covid-19, can compromise the continuity of care for these patients.

Prevalence of Psychiatric Disorders in Aesthetic Surgery.

PURPOSE: Our study aimed to characterize and objectify the prevalence of psychiatric disorders and the use of psychotropic drugs in patients interested in undergoing aesthetic surgery. The psychiatric profile of this population is particularly interesting and is related to self-perception and the general concept of beauty. METHODS: We conducted an observational, retrospective, and bicenter study of 2092 patients seen in plastic surgery departments. Data on general characteristics, pathology, psychiatric history (PH), use of psychotropic drugs, addictions, surgical requests, and surgical complications were recorded and analyzed. RESULTS: Based on our inclusion criteria, we selected 524 patients. The prevalence of psychiatric disorders was 32.25%. The prevalence of depressive disorders (19.27%), anxiety disorders (8.21%), and sleep-wake cycle disorders (7.06%) should be noted. Comparing the population with psychiatric history (PH+) and without psychiatric history (PH-), significant differences were found in patient ethnicity, addictions (tobacco, 37.50% vs 15.00%; drugs, 3.26% vs 0.59%), and comorbidities. In the 66.86% (n = 113) of PH+ patients, the plastic surgeon did not record the presence of psychiatric disorders in the medical record. DISCUSSION: This study offers a broad view of the prevalence and characteristics of psychiatric disorders and the use of psychotropic drugs among patients who want to undergo aesthetic surgery. The prevalence of psychiatric problems in the study population is higher than in the general population (32.25% vs 15.02%). CONCLUSIONS: Our results suggest that plastic surgeons should be properly trained to manage these patients. A multidisciplinary approach involving plastic surgeons, psychiatrists, and psychologists is advocated.

Demographic Study and Description of the Surgical Demand in Aesthetic Surgery.

BACKGROUND: The demand for aesthetic surgery presents a continuously growing trend over the years. The population wishing to undergo this type of surgery presents unique characteristics that are profoundly different in motivational, demographic, and clinical features from patients in other specialties. OBJECTIVES: The aim of our multicenter study is to objectively define the surgical demand and the demographic characteristics of our patients comparing them with general population. We try to better define who are our patients. METHODS: We conducted an observational, multicenter, retrospective study analyzing 3329 consultations involving a total of 2092 patients between January 2019 and June 2019. Based on the inclusion criteria, we selected 524 patients whose demographic characteristics, body mass index, addictions, comorbidities, and aesthetic surgery demand were analyzed. RESULTS: The mean age of our population is 38.58 years (female-to-male ratio, 9:1). The mean body mass index is 27.50 (5.23). A total of 22.90% of the sample have smoking habits, 3.63% have alcohol addiction, 1.53% have drugs addiction, and 53.63% of the population have relevant comorbidities.The 56.68% of the patients have already undergone surgery. The conversion rate of our first consultations to surgery is 49.05%. The most requested operation is abdominoplasty (36.45%), followed by liposuction (22.90%), breast reduction (17.56%), mastopexy (14.79%), and rhinoplasty (7.63%). CONCLUSIONS: This topic is downplayed and seldom studied in the literature; our effort is to make patient profiling crucial and evidence-based in aesthetic surgery.

Exploring students' perspectives from two Canadian dental schools toward online learning experiences.

OBJECTIVES: The utilization of online teaching and learning in dental education has grown during the past two academic years. In addition to its numerous advantages, the modality also has its limitations. The objective of this qualitative study was to explore the perceptions of oral health sciences students at the University of British Columbia (UBC) and the University of Toronto (UofT) regarding their experiences with online learning over the course of 2 pandemic-impacted years. METHODS: Interpretive Description was used as a methodology to guide semi-structured data collection. Individual interviews and focus groups were conducted with graduate and undergraduate dental and dental hygiene students at UBC and UofT. Qualitative data were coded and analyzed using a thematic approach. RESULTS: A total of 31 interviews and 4 focus groups were conducted. Online teaching and learning demonstrated many advantages, including flexibility, sustainability of curricular content, and promoting inclusivity in the classroom. Students indicated that due to online learning, there were opportunities to gain resources in practicing self-care and additional time to connect with family. Reported limitations of online classrooms included the loss of attentiveness, challenging content, and logistical challenges. Isolation and physical symptoms experienced in online classrooms with prolonged screen times were described as potential threats. CONCLUSIONS: The results of this study call for developing a structured and sustainable blended approach that balances the limitations of online classrooms with the interaction and engagement of in-person classrooms and patient care experiences. Based on the students' perspectives toward online learning, a road map was provided to dental educators to consider when designing future dentistry curricula.

Design, synthesis, and biological evaluation of new arjunolic acid derivatives as anticancer agents.

Arjunolic acid (AA) is a pentacyclic triterpenoid with promising anticancer properties. A series of novel AA derivatives containing a pentameric A-ring with an enal moiety, combined with additional modifications at C-28, were designed and prepared. The biological activity on the viability of human cancer and non-tumor cell lines was evaluated in order to identify the most promising derivatives. Additionally, a preliminary study of the structure-activity relationship was carried out. The most active derivative, derivative 26, also showed the best selectivity between malignant cells and non-malignant fibroblasts. For compound 26, the anticancer molecular mechanism of action in PANC-1 cells was further studied and the results showed that this derivative induced a cell-cycle arrest at G0/G1 phase and significantly inhibited the wound closure rate of PANC-1 cancer cells in a concentration-dependent manner. Additionally, compound 26 synergistically increased the cytotoxicity of Gemcitabine, especially at a concentration of 0.24 µM. Moreover, a preliminary pharmacological study indicated that at lower doses this compound did not demonstrate toxicity in vivo. Taken together, these findings suggest that compound 26 may be a valuable compound for the development of new pancreatic anticancer treatment, and further studies are needed to explore its full potential.

Continuity of care for patients recovering from Covid-19 under the angle of clinical management principles / Continuidad asistencial de los pacientes convalecientes de Covid-19 a la luz de los principios de gestión clínica / Continuidade do cuidado a pacientes recuperados da Covid-19 à luz dos princípios da gestão da clínica

ABSTRACT Objective: To analyze the strategies used by nurses at a university hospital to ensure continuity of care at hospital discharge for patients recovered from Covid-19, under the angle of the principles of clinical management. Method: A descriptive study with a qualitative approach, carried out with seven nurses on duty in the medical and gynecology/obstetrics clinics of a university hospital in the Midwest region of the country. The data was processed using IRaMuTeQ software and analyzed using Content Analysis. Results: The data resulted in five classes by the Descending Hierarchical Classification (DHC), which made up two categories: "Practices developed by nurses for continuity of care in the hospital environment" and "Continuity of care during discharge to the home". The strategies used by the nurses were: daily care systematized in the nursing process and guidance both for preparation and for the day of discharge. Conclusion: The absence of an institutional protocol for safe discharge, as well as the position of nurse coordinator to manage the discharge of patients with Covid-19, can compromise the continuity of care for these patients.

RESUMEN Objetivo: Analizar las estrategias utilizadas por el personal de enfermería de un hospital universitario para asegurar la continuidad asistencial al alta hospitalaria de pacientes recuperadas de Covid-19, a la luz de los principios de gestión clínica. Método: Estudio descriptivo con abordaje cualitativo, realizado con siete enfermeras de guardia en las consultas de medicina y ginecología/obstetricia de un hospital universitario de la región centro-oeste del país. Los datos se procesaron con el programa IRaMuTeQ y se analizaron mediante Análisis de Contenido. Resultados: Los datos resultaron en cinco clases por la Clasificación Jerárquica Descendente (CJD), que constituyeron dos categorías: "Prácticas desarrolladas por las enfermeras para la continuidad de los cuidados en el ambiente hospitalario" y "Continuidad de los cuidados durante el alta al domicilio". Las estrategias utilizadas por las enfermeras fueron: cuidados diarios sistematizados en el proceso de enfermería y orientación tanto para la preparación como para el día del alta. Conclusión: La ausencia de un protocolo institucional para el alta segura, así como del cargo de enfermera coordinadora para gestionar el alta de pacientes con covid-19, puede comprometer la continuidad de cuidados de estos pacientes.

RESUMO Objetivo: Analisar as estratégias utilizadas por enfermeiros de um hospital universitário para garantir continuidade do cuidado na alta hospitalar de pacientes recuperados da Covid-19, à luz dos princípios da gestão da clínica. Método: Estudo descritivo de abordagem qualitativa, realizado com sete enfermeiros plantonistas das clínicas médicas e ginecologia/obstetrícia de um hospital universitário da região centro-oeste do país. Os dados foram processados pelo software IRaMuTeQ e analisados pelo método de Análise de Conteúdo. Resultados: Os dados resultaram em cinco classes pela Classificação Hierárquica Descendente (CHD), que compôs duas categorias: "Práticas desenvolvidas pelos enfermeiros para a continuidade do cuidado no ambiente hospitalar" e "Continuidade do cuidado durante a alta hospitalar para o domicílio". As estratégias utilizadas pelos enfermeiros foram: cuidados diários sistematizados no processo de enfermagem e orientações tanto para o preparo quanto para o dia de alta. Conclusão: A ausência de protocolo institucional para alta segura, bem como o cargo de enfermeira coordenadora para gerenciar as altas dos pacientes com Covid-19 podem comprometer a continuidade do cuidado a esses pacientes.

Use of carbohydrate-directed enzymes for the potential exploitation of sugarcane bagasse to obtain value-added biotechnological products.

Microorganisms, such as fungi and bacteria, are crucial players in the production of enzymatic cocktails for biomass hydrolysis or the bioconversion of plant biomass into products with industrial relevance. The biotechnology industry can exploit lignocellulosic biomass for the production of high-value chemicals. The generation of biotechnological products from lignocellulosic feedstock presents several bottlenecks, including low efficiency of enzymatic hydrolysis, high cost of enzymes, and limitations on microbe metabolic performance. Genetic engineering offers a route for developing improved microbial strains for biotechnological applications in high-value product biosynthesis. Sugarcane bagasse, for example, is an agro-industrial waste that is abundantly produced in sugar and first-generation processing plants. Here, we review the potential conversion of its feedstock into relevant industrial products via microbial production and discuss the advances that have been made in improving strains for biotechnological applications.

Intrafractional monitoring of patients using four different immobilization mask systems for cranial radiotherapy.

Background and purpose: Patients receiving cranial radiotherapy are immobilized with a thermoplastic mask to restrict patient motion. Depending on the target volume margins and treatment dose, different mask systems are used. Intrafractional movements can be monitored using stereoscopic X-ray imaging. The aim of the present work was to compare the magnitudes of intrafractional deviation for different mask systems. Material and methods: Four different head mask systems (open face mask, open mask, stereotactic mask, double mask) used in the treatment of 40 patients were investigated. In total 487 treatment fractions and 3708 X-ray images were collected. Deviations were calculated by comparison of the acquired X-ray images with digitally reconstructed radiographs. The results of intrafractional X-ray deviations for translational and rotational axes were compared between the different mask systems. Results: Deviations were below 0.6 mm for translations and below 0.6° for rotations for all mask systems. Along the lateral and longitudinal directions the stereotactic mask was superior, while along the vertical direction the double mask showed the lowest deviations. For low rotational deviations the double mask is the best amongst all other mask systems. Conclusion: As expected, the lowest movement was shown using cranial stereotactic mask systems. The results have shown deviations lower than 0.6 mm and 0.6° using any of the four thermoplastic mask systems.

Diversity of Phospholipases A2 from Bothrops atrox Snake Venom: Adaptive Advantages for Snakes Compromising Treatments for Snakebite Patients.

The evolution of snake venoms resulted in multigene toxin families that code for structurally similar isoforms eventually harboring distinct functions. PLA2s are dominant toxins in viper venoms, and little is known about the impact of their diversity on human envenomings and neutralization by antivenoms. Here, we show the isolation of three distinct PLA2s from B. atrox venom. FA1 is a Lys-49 homologue, and FA3 and FA4 are catalytic Asp-49 PLA2s. FA1 and FA3 are basic myotoxic proteins, while FA4 is an acid non-myotoxic PLA2. FA3 was the most potent toxin, inducing higher levels of edema, inflammatory nociception, indirect hemolysis, and anticoagulant activity on human, rat, and chicken plasmas. FA4 presented lower anticoagulant activity, and FA1 had only a slight effect on human and rat plasmas. PLA2s presented differential reactivities with antivenoms, with an emphasis on FA3, which was not recognized or neutralized by the antivenoms used in this study. Our findings reveal the functional and antigenic diversity among PLA2s from B. atrox venom, highlighting the importance of assessing venom variability for understanding human envenomations and treatment with antivenoms, particularly evident here as the antivenom fails to recognize FA3, the most active multifunctional toxin described.

ExacTrac Dynamic workflow evaluation: Combined surface optical/thermal imaging and X-ray positioning.

In modern radiotherapy (RT), especially for stereotactic radiotherapy or stereotactic radiosurgery treatments, image guidance is essential. Recently, the ExacTrac Dynamic (EXTD) system, a new combined surface-guided RT and image-guided RT (IGRT) system for patient positioning, monitoring, and tumor targeting, was introduced in clinical practice. The purpose of this study was to provide more information about the geometric accuracy of EXTD and its workflow in a clinical environment. The surface optical/thermal- and the stereoscopic X-ray imaging positioning systems of EXTD was evaluated and compared to cone-beam computed tomography (CBCT). Additionally, the congruence with the radiation isocenter was tested. A Winston Lutz test was executed several times over 1 year, and repeated end-to-end positioning tests were performed. The magnitude of the displacements between all systems, CBCT, stereoscopic X-ray, optical-surface imaging, and MV portal imaging was within the submillimeter range, suggesting that the image guidance provided by EXTD is accurate at any couch angle. Additionally, results from the evaluation of 14 patients with intracranial tumors treated with open-face masks are reported, and limited differences with a maximum of 0.02 mm between optical/thermal- and stereoscopic X-ray imaging were found. As the optical/thermal positioning system showed a comparable accuracy to other IGRT systems, and due to its constant monitoring capability, it can be an efficient tool for detecting intra-fractional motion and for real-time tracking of the surface position during RT.

Relevant insights into onychomycosis' pathogenesis related to the effectiveness topical treatment.

Onychomycosis (OM) is a fungal infection, responsible for about 50% of nail diseases. OM has been attributed to the ability of fungi to naturally organize themselves into biofilms on nail surfaces. However, little is known about the exact role of the biofilm in the etiopathogenesis of OM, as well as its influence in the permeation of a topical treatment. The objectives of this study were to review the literature for topical OM treatments in clinical trials, assess the efficiency of these treatments, and discuss factors that could affect the success of these treatments. First, a systematic search of articles published in the MEDLINE database (PubMed) between January 2010 and December 2019 was conducted, focusing on drugs under clinical trials for the topical treatment of OM. Of the publications selected, it was clear that none of them had considered the fungi organized in biofilm. Therefore, we reflected on some important variables involved in OM, such as the nail structure and the mechanism of fungal invasion. Some methods, such as histopathologic analysis and spectroscopy techniques, were found to be effective in the detection of nail biofilm, and could be used in future drug permeation studies. This review allowed us to conclude that novel antifungals for the topical treatment of OM must consider the drug to permeate through biofilm. Natural products, such as propolis, seem strong candidates in this respect.

Dosimetric benefit of MR-guided online adaptive radiotherapy in different tumor entities: liver, lung, abdominal lymph nodes, pancreas and prostate.

BACKGROUND: Hybrid magnetic resonance (MR)-Linac systems have recently been introduced into clinical practice. The systems allow online adaption of the treatment plan with the aim of compensating for interfractional anatomical changes. The aim of this study was to evaluate the dose volume histogram (DVH)-based dosimetric benefits of online adaptive MR-guided radiotherapy (oMRgRT) across different tumor entities and to investigate which subgroup of plans improved the most from adaption. METHODS: Fifty patients treated with oMRgRT for five different tumor entities (liver, lung, multiple abdominal lymph nodes, pancreas, and prostate) were included in this retrospective analysis. Various target volume (gross tumor volume GTV, clinical target volume CTV, and planning target volume PTV) and organs at risk (OAR) related DVH parameters were compared between the dose distributions before and after plan adaption. RESULTS: All subgroups clearly benefited from online plan adaption in terms of improved PTV coverage. For the liver, lung and abdominal lymph nodes cases, a consistent improvement in GTV coverage was found, while many fractions of the prostate subgroup showed acceptable CTV coverage even before plan adaption. The largest median improvements in GTV near-minimum dose (D98%) were found for the liver (6.3%, p < 0.001), lung (3.9%, p < 0.001), and abdominal lymph nodes (6.8%, p < 0.001) subgroups. Regarding OAR sparing, the largest median OAR dose reduction during plan adaption was found for the pancreas subgroup (-87.0%). However, in the pancreas subgroup an optimal GTV coverage was not always achieved because sparing of OARs was prioritized. CONCLUSION: With online plan adaptation, it was possible to achieve significant improvements in target volume coverage and OAR sparing for various tumor entities and account for interfractional anatomical changes.

A Surgical Alternative in the Treatment of Hypopharyngeal Perforation.

Pharyngo-esophageal perforation is a rare, life-threatening complication of anterior cervical discectomy and fusion surgery with an incidence estimated to be between 0.2 and 1.51%. Early diagnosis and appropriate treatment of this complication is the key to reduce morbidity and mortality, as the main prognostic factor is the interval between the onset of the fistula, diagnosis and treatment. Conservative management has shown encouraging results in small and localized defects, whereas surgical approaches using flaps are to be considered for most of the cases. However, there is no clear consensus on the first choice of treatment in esophageal perforation. This case report presents the use of a supra-clavicular fascio-cutaneous pedicled propeller flap as a patch combined to primary repair of a hypopharyngeal perforation, 10 years after anterior cervical spine arthrodesis.

Diversity of phospholipases A2 from Bothrops atrox snake venom: adaptive advantages for snakes compromising treatments for snakebite patients

The evolution of snake venoms resulted in multigene toxin families that code for structurally similar isoforms eventually harboring distinct functions. PLA2s are dominant toxins in viper venoms, and little is known about the impact of their diversity on human envenomings and neutralization by antivenoms. Here, we show the isolation of three distinct PLA2s from B. atrox venom. FA1 is a Lys-49 homologue, and FA3 and FA4 are catalytic Asp-49 PLA2s. FA1 and FA3 are basic myotoxic proteins, while FA4 is an acid non-myotoxic PLA2. FA3 was the most potent toxin, inducing higher levels of edema, inflammatory nociception, indirect hemolysis, and anticoagulant activity on human, rat, and chicken plasmas. FA4 presented lower anticoagulant activity, and FA1 had only a slight effect on human and rat plasmas. PLA2s presented differential reactivities with antivenoms, with an emphasis on FA3, which was not recognized or neutralized by the antivenoms used in this study. Our findings reveal the functional and antigenic diversity among PLA2s from B. atrox venom, highlighting the importance of assessing venom variability for understanding human envenomations and treatment with antivenoms, particularly evident here as the antivenom fails to recognize FA3, the most active multifunctional toxin described.

Dosimetric comparison of MR-linac-based IMRT and conventional VMAT treatment plans for prostate cancer.

BACKGROUND: The aim of this study was to evaluate and compare the performance of intensity modulated radiation therapy (IMRT) plans, planned for low-field strength magnetic resonance (MR) guided linear accelerator (linac) delivery (labelled IMRT MRL plans), and clinical conventional volumetric modulated arc therapy (VMAT) plans, for the treatment of prostate cancer (PCa). Both plans used the original planning target volume (PTV) margins. Additionally, the potential dosimetric benefits of MR-guidance were estimated, by creating IMRT MRL plans using smaller PTV margins. MATERIALS AND METHODS: 20 PCa patients previously treated with conventional VMAT were considered. For each patient, two different IMRT MRL plans using the low-field MR-linac treatment planning system were created: one with original (orig.) PTV margins and the other with reduced (red.) PTV margins. Dose indices related to target coverage, as well as dose-volume histogram (DVH) parameters for the target and organs at risk (OAR) were compared. Additionally, the estimated treatment delivery times and the number of monitor units (MU) of each plan were evaluated. RESULTS: The dose distribution in the high dose region and the target volume DVH parameters (D98%, D50%, D2% and V95%) were similar for all three types of treatment plans, with deviations below 1% in most cases. Both IMRT MRL plans (orig. and red. PTV margins) showed similar homogeneity indices (HI), however worse values for the conformity index (CI) were also found when compared to VMAT. The IMRT MRL plans showed similar OAR sparing when the orig. PTV margins were used but a significantly better sparing was feasible when red. PTV margins were applied. Higher number of MU and longer predicted treatment delivery times were seen for both IMRT MRL plans. CONCLUSIONS: A comparable plan quality between VMAT and IMRT MRL plans was achieved, when applying the same PTV margin. However, online MR-guided adaptive radiotherapy allows for a reduction of PTV margins. With a red. PTV margin, better sparing of the surrounding tissues can be achieved, while maintaining adequate target coverage. Nonetheless, longer treatment delivery times, characteristic for the IMRT technique, have to be expected.

Gastric outlet obstruction - looking for a syndrome: Bouveret or Mirizzi?

INTRODUCTION AND IMPORTANCE: Gastric outlet obstruction can result from any pathological process that causes intrinsic blockage or extrinsic pressure on the distal stomach and duodenum. Gallstone related gastric outlet obstruction is a well-known entity classically due to a cholecystoenteric fistula formation. CASE PRESENTATION: We present here a case of a 36-year-old man who presented with right upper quadrant abdominal pain associated with marked nausea and vomiting. Abdominal CT scan done in the emergency department revealed a large impacted infundibular gallstone with signs of acute cholecystitis, associated with prominent gastric distention. Gastric outlet obstruction was due to stenosis at the duodenal level from external compression by the large impacted stone with no evidence of fistula. Laparoscopic cholecystectomy was performed with total resolution of symptoms. CLINICAL DISCUSSION: Gastric outlet obstruction can be secondary to many etiologies, and notably gallstone disease. Classically this is due to formation of a cholecystoenteric fistula and intrinsic obstruction by the migrated stone. Our case is unique in that a large impacted infundibular gallstone caused gastric outlet obstruction with absence of any fistula or gallstone migration. CONCLUSION: Gastric outlet obstruction due to external compression by a non-migrated gallstone is a rare undescribed entity. Surgical treatment should not be delayed to prevent complications and fistula formation.