A case report of an unexpected colonic polyp: cavernous hemangioma

Mascarenhas Miguel,Morais Rui,Teixeira Regina,Macedo Guilherme 대한대장항문학회 2023 Annals of Coloproctolgy Vol.39 No.3

Cavernous hemangiomas of the colon are rare, benign vascular lesions, and the site most commonly affected is the rectosigmoid junction. Surgical treatment is recommended for large diffuse lesions but in the presence of pedunculated lesions, endoscopic resection should be preferred if possible. We report a case of a 65-year-old man referred for colonoscopy after positive fecal occult blood, that revealed at the level of the sigmoid colon, a wide base pedunculated polyp (35 mm) occupying more than half of the lumen, with the covering mucosa with a vinous appearance. In order to remove the lesion, a detachable snare was placed and polypectomy was performed. During the procedure, the detachable snare was cut with active bleeding, controlled after clip placement and diluted adrenaline injection. Afterwards, histology revealed a polypoid lesion with a hyperplastic mucosa and submucosal plane expanded by numerous thick-walled vessels in the context of a cavernous colonic hemangioma.

Simulation-based education for selected communication skills: exploring the perception of post-graduate dental students

Sharon Mascarenhas,Manal Al-Halabi,Farah Otaki,Mohamed Nasaif,Dave Davis 한국의학교육학회 2021 Korean journal of medical education Vol.33 No.1

Purpose: The role of simulation-based education (SBE) in enhancing communication has been established in the literature. To ensure achieving desired outcomes from SBE initiative, the individual learners, their experiences, and environments need to be considered. This study aimed at exploring the perception of post-graduate dental students regarding their participation in SBE sessions, around selected communication skills, designed in alignment with the assumptions of adult learning theory and steps of Kolb’s experiential learning cycle. Methods: This study utilized a qualitative design. Six focus-group sessions were conducted following the SBE sessions. The generated data was inductively investigated using a multi-staged participant-focused approach to thematic analysis, based upon constructivist epistemology. NVivo was utilized to facilitate text Fragments’ coding and categorization. Results: Forty-three post-graduate dental students participated. The analysis resulted in 16 categories spread across five sequential phases of the SBE experience. The “input” theme referred to the resources needed for the SBE process, and included three categories: facilities, personnel, and teaching materials. The second theme included steps of SBE “process”: pre-brief, simulation, and debrief. The third, fourth, and fifth themes constituted the short- and longer-term results of the SBE intervention. The participants reported instant benefits on confidence in their expertise in communicating with patients and their guardians. Additionally, perceived effects on the empathy and professionalism were reported. Conclusion: SBE, that is based upon adult and experiential learning theories, and developed after thorough consideration of the individual learners, and their experiences and learning environments, holds potential in enhancing communication skills among post-graduate dental students.

Catalytic hydrogenation of organic dyes by Ag nanoparticles on reduced graphene oxide

Bruno C. Mascarenhas,Laudemir C. Varanda 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Stable, efficient, and reusable catalysts for wastewater treatment, promoting the catalytic elimination ofenvironmental pollutants remains a current challenge. This work shows a one-pot synthesize Agnanoparticles (AgNPs) supported on reduced graphene oxide (rGO/Ag) as a nanocatalyst. Morphological control of AgNPs was achieved by adding NH4OH during the nucleation and growth processesleading to the spherical nanoparticles with average size of 9 ± 3 nm). Temperature increase promotesdecrease of the oxygenated functional groups on rGO sheets, with an ID/IG = 0.57 at 300 C. Catalyticactivity of rGO/Ag was investigated through the catalytic hydrogenation of methylene blue (MB) and rhodamineB (RhB) in the presence of NaBH4 as a reducing agent. The proposed mechanism is based on thetransfer of 2e and 1H+ between the nanocatalyst and the dye molecules. Dyes adsorption on the catalystis a rate-determining step and was accelerated by the rGO support. X-ray photoelectron spectroscopyanalysis before and after successive catalytic cycles indicated that the catalyst integrity was maintained,with a slight decrease in the silver amount from 4.53 to 3.78 at%. The decolorization reaction followed thepseudo-first-order kinetics model for both dyes, and our results showed an efficiency of around 30%higher than similar methods.

Does the general public have concerns with dental anesthetics?

Razon, Jonathan,Mascarenhas, Ana Karina The Korean Dental Society of Anesthsiology 2021 Journal of Dental Anesthesia and Pain Medicine Vol.21 No.2

Background: Consumers and patients in the last two decades have increasingly turned to various internet search engines including Google for information. Google Trends records searches done using the Google search engine. Google Trends is free and provides data on search terms and related queries. One recent study found a large public interest in "dental anesthesia". In this paper, we further explore this interest in "dental anesthesia" and assess if any patterns emerge. Methods: In this study, Google Trends and the search term "dental pain" was used to record the consumer's interest over a five-year period. Additionally, using the search term "Dental anesthesia," a top ten related query list was generated. Queries are grouped into two sections, a "top" category and a "rising" category. We then added additional search term such as: wisdom tooth anesthesia, wisdom tooth general anesthesia, dental anesthetics, local anesthetic, dental numbing, anesthesia dentist, and dental pain. From the related queries generated from each search term, repeated themes were grouped together and ranked according to the total sum of their relative search frequency (RSF) values. Results: Over the five-year time period, Google Trends data show that there was a 1.5% increase in the search term "dental pain". Results of the related queries for dental anesthesia show that there seems to be a large public interest in how long local anesthetics last (Total RSF = 231) - even more so than potential side effects or toxicities (Total RSF = 83). Conclusion: Based on these results it is recommended that clinicians clearly advice their patients on how long local anesthetics last to better manage patient expectations.

Poster Session:PS 0569 ; Oncology : Pancreatic Cancer Causing Heart Failure

( Armando Lopes Braz ),( Tiago Mascarenhas ),( Conceicao Quadrado ),( Jose Braz Nogueira ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

A 67-year-old patient was sent to the internal medicine consultation due to dyspnea, orthopnea and lower limb edemas for 6 month, which got worse in the past 2 weeks, with diffi cult stabilization and control, even with intense therapy for heart failure. The therapy was improved and an echocardiogram was requested. One month later she was reevaluated showing no clinical improvement, so she was admitted in the internal medicine ward. The echocardiogram showed an ejection fraction of 21%, increased right chambers, severe pulmonary hypertension and left ventricle dilatation with depressed cardiac function. The therapy for heart failure was optimized and a ventilation-perfusion scyntigraphy was performed to evaluate the respiratory system. It revealed areas of pulmonary collapse and pulmonary embolism. On the ward she suffered a sudden episode of dyspnea and left leg edema and experienced severe pain. An ultrasound of the lower limbs proved the existence of bilateral severe deep venous thrombosis. For a further investigation the patient did a body CT-scan and cancer markers were searched. The CA19.9 was 253679 and there were several metastatic lesions on the liver and an infracentrimetic mass on the pancreatic tail on the CTScan. She started anticoagulation for prevention of other pulmonary embolism, while waiting for a pancreatic biopsy. The patient died 3 month after the diagnosis due to a sudden Myocardial infarction. The symptoms of heart failure dominated the whole clinical picture, being the DVT the wind of change to establish the diagnosis of pancreatic cancer, a scary disease that was silent for so long. This case shows the importance of the paraneoplastic symptoms such the bilateral DVT which was the important milestone for a further investigation and the fi nal diagnose.

Determination of Carrier Concentration in Ga1-xMnxAs Using Raman Spectrocopy

명제 성,A Mascarenhas,Cheongy Cheongy,N Samarth,S. H. Chunz 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.42 No.III

Ga$_{1-x}$Mn$_{x}$As with Curie temperatures ($T_c$) as high as 110 K has recently emerged as an important spintronic semiconductor material. The ferromagnetism in this material arises from the exchange interaction between the free carriers (holes) generated by Mn doping and the Mn$^{2+}$ ions. However, the accurate determination of the carrier concentration in Ga$_{1-x}$Mn$_{x}$As using standard transport techniques is extremely difficult because of the dominant anomalous Hall effect. We have performed spectroscopic measurements of the hole density in four Ga$_{1-x}$Mn$_{x}$As samples ($x = 0, 0.038, 0.061, 0.083$) using Raman scattering intensity analysis of the coupled plasmon-LO-phonon mode and the unscreened LO phonon. The unscreened LO phonon frequency linearly decreases as the Mn concentration increases up to 8.3 \%. The hole density determined from the Raman scattering exhibits a direct correlation to the observed $T_c$, providing an unambiguous means of determining the hole density in this important new class of ferromagnetic semiconductors.

Resonant Raman Study on the Nitrogen-Induced Electronic States in GaAs$_{1-x}$N$_{x}$

M. J. Seong,A. Mascarenhas,정현식,J. F. Geisz,M. C. Hanna,윤석현 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.1

Nitrogen-induced electronic states, encompassing E0 through E+, in GaAs1%) have been probed using resonant Raman scattering. We have observed strong Raman intensity resonance enhancement for the L and X zone boundary phonons as well as the zone center phonons for excitations near the E+ transition, which provides unambiguous evidence of signicant L and X components in the wave function of the nitrogen-induced E+ state in GaAs1 The resonant Raman scattering prole for the asymmetric line-width broadening of the LO phonon exhibits two distinct maxima attributed to states arising from a splitting of the quadruply degenerate conduction band near the L-point.

Poster Session : PS 0389 ; Infectious Disease ; Vasculitis Caused by Infectious Agent or Allergic Reaction

( Armando Lopes Braz ),( Tiago Mascarenhas ),( Conceicao Quadrado ),( Jose Braz Nogueira ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

The clinical case is about a 44 years old male patient who was transferred to our hospital due to vasculitis. He was living in Angola for 8 years, being healthy until 2 weeks before being transferred. He started to feel abdominal cramps, muscular and joint pain over a period of 3 days. He was admitted in a clinic suspecting of malaria, starting antimalarial medication. On the 3rd day, the blood results for infectious diseases and maliaria were negative. He stooped the treatment and was discharged. After 4 days the patient started to complain of the same symptoms aggravated with asthenia, tiredness and diarrhea. He was readmitted and treated with antibiotics. Three days later some petequial lesions appeared in the lower limbs, getting spread arms and ears. These lesions got bigger over the next 2 days becoming macules and then changed to penfi - goid lesions with central necroses. The lesions covered the all lower limbs and part of the upper limbs, spearing the trunk. Corticosteroids were added to the treatment but he got worse, being later transferred to our hospital. The fi rst evaluation revealed a severe lower limbs edema, hypoalbuminemia and renal failure. All the treatment was stooped apart of pain killers and done some skin biopsies. The result was positive for leukocytoclastic vasculitis. Because of the GIT symptoms an endoscopy and colonoscopy was performed. The gut was covered with extense ulcerative lesions and was identifi ed inside them CMV. The body CT and Abdominal ultrasound were normal. The patient started the treatment with Valaciclovir during 15 days, followed with 6 weeks of Ganciclovir. This case still covered in dough, because it`s impossible to know if the hypersensibility reaction to the anti-malary drugs started the vasculites, triggering the CMV infection or the CMV developed the vasculitis.

Case Report : Bilateral Osteochondritis Dissecans of the Femoral Condyles in Both Knees; A Report of Two Sibling Cases

( Jae Hoon Jeong ),( Randy Mascarenhas ),( Hang Seob Yoon ) 대한슬관절학회 2013 대한슬관절학회지 Vol.25 No.2

Osteochondritis dissecans (OCD) of both femoral condyles is very rare, with no previously reported cases of bilateral OCD of both knees in two siblings. We report on a brother and sister with both femoral condyle OCD with a description of surgical technique and clinical results. Fixation using headless compressive screws, osteochondral autologous transplantation and autologous chondrocyte implantation were all successful.

(Cyto)genomic and epigenetic characterization of BICR 10 cell line and three new established primary human head and neck squamous cell carcinoma cultures

Ilda P. Ribeiro,Joana M. Rodrigues,Alexandra Mascarenhas,Vanessa Marques,Francisco Caramelo,Maria J. Julião,Thomas Liehr,Joana B. Melo,Isabel M. Carreira 한국유전학회 2019 Genes & Genomics Vol.41 No.10

Background Head and neck squamous cell carcinoma cell lines are useful preclinical models to understand the molecular processes underlying the development of such tumors, and to establish targeted therapies. Objective We performed a comprehensive (cyto)genomic and epigenetic characterization of three new established primary human head and neck squamous cell carcinoma cultures and an established, yet undercharacterized cell line: BICR 10. Methods Karyotyping, multiplex fluorescence in situ hybridization, array comparative genomic hybridization and methylation- specific multiplex ligation-dependent probe amplification were applied. Results The three primary cultures turned out to be a near-triploid and BICR 10 near-diploid. Banding and molecular cytogenetic analysis revealed non-random numerical and structural aberrations. The most common rearrangements identified in BICR 10 cell line were non-complex derivatives of reciprocal translocations, in which the breakpoints often appeared in centromeric/near-centromeric regions. In the 3 primary cell cultures the most common rearrangements observed were iso- and derivatives chromosomes derived from translocations. Overall, gains of 7p, 8q and losses at 3p, 8p, 9p, 18q and Xp were present in all four studied samples. Among the analyzed genes, BICR 10 cell line exhibited enhanced methylation of gene promoter; however, in all studied samples PAX5, WT1 and GATA5 were methylated. Conclusion The here reported comprehensive characterization of BICR 10 cell line and the new established cultures enriches the resources available for head and neck cancer research, especially for testing therapeutic agents.