Methylene blue as an adjuvant during cardiopulmonary resuscitation: an experimental study in rats.

INTRODUCTION: Methylene Blue (MB) has been shown to attenuate oxidative, inflammatory, myocardial, and neurological lesions during ischemia-reperfusion and has great potential during cardiac arrest. This study aimed to determine the effects of MB combined with epinephrine during cardiac arrest on myocardial and cerebral lesions. METHOD: Thirty-eight male Wistar rats were randomly assigned to four groups: the sham group (SH, n = 5), and three groups subjected to cardiac arrest (n = 11/group) and treated with EPI 20 µg.kg-1 (EPI), EPI 20 µg.kg-1 + MB 2 mg.kg-1 (EPI + MB), or saline 0.9% 0.2 ml (CTL). Ventricular fibrillation was induced by direct electrical stimulation in the right ventricle for 3 minutes, and anoxia was maintained for 5 minutes. Cardiopulmonary Resuscitation (CPR) consisted of medications, ventilation, chest compressions, and defibrillation. After returning to spontaneous circulation, animals were observed for four hours. Blood gas, troponin, oxidative stress, histology, and TUNEL staining measurements were analyzed. Groups were compared using generalized estimating equations. RESULTS: No differences in the Returning of Spontaneous Circulation (ROSC) rate were observed among the groups (EPI: 63%, EPI + MB: 45%, CTL: 40%, p = 0.672). The mean arterial pressure immediately after ROSC was higher in the EPI+MB group than in the CTRL group (CTL: 30.5 [5.8], EPI: 63 [25.5], EPI+MB: 123 [31] mmHg, p = 0.007). Serum troponin levels were high in the CTL group (CTL: 130.1 [333.8], EPI: 3.70 [36.0], EPI + MB: 43.7 [116.31] ng/mL, p < 0.05). CONCLUSION: The coadministration of MB and epinephrine failed to yield enhancements in cardiac or brain lesions in a rodent model of cardiac arrest.

Diffuse large B-cell lymphoma: morphologic and immunohistochemical analysis of bone marrow for staging, with emphasis on lymphoid aggregates.

Diffuse large B-Cell lymphoma (DLBCL) may infiltrate bone marrow (BM) and evaluation of BM plays an important role in DLBCL staging. This study used BM samples from DLBCL patients for staging and analyzed the use of immunohistochemistry in the diagnostic management of these cases by the pathologist. Patients with DLBCL submitted to BM biopsy/aspiration for staging were studied according to clinical aspects, morphologic aspects, and expression of CD20 and CD3. The characteristics of lymphoid aggregates in the bone marrow and the power of histopathological diagnosis were studied, with immunohistochemistry as the gold standard for the decision of a neoplastic infiltration definition. An isolated morphological analysis showed low sensitivity (42.9%) for lymphoma detection in BM, which is disadvantageous. The median of three lymphoid aggregates in the BM (p-value = 0.02) and the presence of increased reticulin fibers (grade 2) in the lymphoid aggregate (p-value = 0.01) had significant associations with neoplastic infiltration. A morphological analysis must be accompanied by an immunohistochemical analysis in all cases, or when this is not possible, in cases with two or more lymphoid aggregates or an increase of reticulin within them.

Indeterminate thyroid cytology: detecting malignancy using analysis of nuclear images.

BACKGROUND: Thyroid nodules diagnosed as 'atypia of undetermined significance/follicular lesion of undetermined significance' (AUS/FLUS) or 'follicular neoplasm/suspected follicular neoplasm' (FN/SFN), according to Bethesda's classification, represent a challenge in clinical practice. Computerized analysis of nuclear images (CANI) could be a useful tool for these cases. Our aim was to evaluate the ability of CANI to correctly classify AUS/FLUS and FN/SFN thyroid nodules for malignancy. METHODS: We studied 101 nodules cytologically classified as AUS/FLUS (n = 68) or FN/SFN (n = 33) from 97 thyroidectomy patients. Slides with cytological material were submitted for manual selection and analysis of the follicular cell nuclei for morphometric and texture parameters using ImageJ software. The histologically benign and malignant lesions were compared for such parameters which were then evaluated for the capacity to predict malignancy using the classification and regression trees gini model. The intraclass coefficient of correlation was used to evaluate method reproducibility. RESULTS: In AUS/FLUS nodule analysis, the benign and malignant nodules differed for entropy (P < 0.05), while the FN/SFN nodules differed for fractal analysis, coefficient of variation (CV) of roughness, and CV-entropy (P < 0.05). Considering the AUS/FLUS and FN/SFN nodules separately, it correctly classified 90.0 and 100.0% malignant nodules, with a correct global classification of 94.1 and 97%, respectively. We observed that reproducibility was substantially or nearly complete (0.61-0.93) in 10 of the 12 nuclear parameters evaluated. CONCLUSION: CANI demonstrated a high capacity for correctly classifying AUS/FLUS and FN/SFN thyroid nodules for malignancy. This could be a useful method to help increase diagnostic accuracy in the indeterminate thyroid cytology.

Typical Lung Carcinoids with Metastasis: Potential Role of MicroRNAs in the Regulation of Adaptive Immunity Associated with Disease: a Case Study.

BACKGROUND/AIMS: Lung carcinoids are uncommon neuroendocrine tumours. Molecular features of lung carcinoids have been poorly defined. microRNAs (miRNAs) are potent gene expression regulators with important roles in cancer development and progression. However, little is known on the role of miRNAs in the pathogenesis of lung carcinoids. Our goals were to identify commonly deregulated miRNAs in a rare case of lung carcinoid of typical histology with metastasis, as well as map miRNA target genes in pathways potentially associated with disease development and progression. METHODS: miRNA expression profiles were assessed using the TaqMan Low Density Arrays, which is a platform including 384 miRNAs. miRNA profiles were generated in the tumor and its corresponding lymph node metastasis, compared to reference normal lung tissues. Furthermore, miRNA expression was validated in a separate, publicly available external dataset (n=19 typical lung carcinoids; 2/19 were metastatic tumors, compared to six normal lung tissues, GSE77380). Following this analysis, computational tools were applied for data interpretation. miRTarBase was used to determine miRNA-target genes, followed by ToppGene Suite analysis to identify pathways and biological functions. In addition, the expression of genes targeted by miRNAs was validated in a second, separate external dataset (n=13 tumour samples, GSE35679). GEO2R data analysis tool was used in both validation analyses (miRNAs and genes). RESULTS: We identified 15 commonly significantly downregulated miRNAs (fold change, FC≥2 and p<0.05) in the tumour and its paired metastasis, with further decreasing levels in the metastatic lesion. Downregulation of miR-126-3p and miR-146b-5p was validated in the external dataset GSE77380. In addition, SOX2 and TCF4 genes, targeted by miR-126-3p, were consistently overexpressed in a subset of six typical lung carcinoids from the external dataset GSE35679. Pathways analysis showed that miRNAs miR-126-3p and miR-146b-5p target genes with a role in the regulation of adaptive immune response. CONCLUSION: Our results contribute to the identification of miRNA expression changes in a typical lung carcinoid and its corresponding lymph node metastasis. Down-regulated levels of miR-126-3p and miR-146b-5p and target gene over-expression could play a role in the progression of this case of primary typical lung carcinoid to regional metastasis. Identified miRNAs and target genes are potential candidates for validation in a larger number of cases.

Follicular thyroid lesions: is there a discriminatory potential in the computerized nuclear analysis?

BACKGROUND: Computerized image analysis seems to represent a promising diagnostic possibility for thyroid tumors. Our aim was to evaluate the discriminatory diagnostic efficiency of computerized image analysis of cell nuclei from histological materials of follicular tumors. METHODS: We studied paraffin-embedded materials from 42 follicular adenomas (FA), 47 follicular variants of papillary carcinomas (FVPC) and 20 follicular carcinomas (FC) by the software ImageJ. Based on the nuclear morphometry and chromatin texture, the samples were classified as FA, FC or FVPC using the Classification and Regression Trees method. RESULTS: We observed high diagnostic sensitivity and specificity rates (FVPC: 89.4% and 100%; FC: 95.0% and 92.1%; FA: 90.5 and 95.5%, respectively). When the tumors were compared by pairs (FC vs FA, FVPC vs FA), 100% of the cases were classified correctly. CONCLUSION: The computerized image analysis of nuclear features showed to be a useful diagnostic support tool for the histological differentiation between follicular adenomas, follicular variants of papillary carcinomas and follicular carcinomas.

Acute lymphoblastic leukemia: primary bone manifestation with hypercalcemia in a child / Leucemia linfoblástica aguda: manifestação óssea primária com hipercalcemia em criança

ABSTRACT Primary bone manifestation associated with hypercalcemia is an infrequent presentation of acute lymphoblastic leukemia (ALL) in children. An 8-year-old girl was admitted with bone and abdomen pain, vomiting, fever, headache, anemia, elevated serum calcium and normal parathyroid hormone levels. Bone radiographs: osteolytic lesions. Bone marrow biopsy showed an infiltration by ALL with immunohistochemical positivity for CD45, CD20, CD79a, TdT and CD10, clinically characterized by hypercalcemia, multifocal osteolytic lesions and single cytopenia. Bone marrow biopsy was a relevant aid in establishing the diagnosis of multifocal osteolytic lesions, associated with hypercalcemia.

RESUMO Apresentação óssea primária associada à hipercalcemia é manifestação clinicolaboratorial infrequente de leucemia linfoblástica aguda (LLA) em crianças. Relatamos o caso de uma criança do sexo feminino, 8 anos, admitida com dores ósseas e no abdômen associadas a vômitos, febre, cefaleia, anemia, hipercalcemia e níveis de paratormônio normais. Radiografias ósseas apresentaram lesões osteolíticas. Biópsia de medula óssea demonstrou infiltração por LLA com positividade imuno-histoquímica para CD45, CD79a, TdT e CD10, clinicamente caracterizada por hipercalcemia, lesões osteolíticas multifocais e citopenia única. A biópsia de medula óssea é importante ferramenta no estabelecimento do diagnóstico de lesões osteolíticas multifocais associada à hipercalcemia.

Pierre Robin sequence: case report, the relevance of autopsy / Sequência de Pierre Robin: relato de caso, a relevância da autópsia

ABSTRACTPierre Robin sequence is a neonatal disorder characterized by micrognathism, glossoptosis and cleft palate. We reported an autopsy case of a child whose malformations of the oropharynx were identified only at birth. The child was extremely preterm with severe neonatal depression and poor recovery, and the orofacial alterations prevented the correct treatment. There was facial disorder characterized by micrognathia associated with cleft palate and posterior displacement of the tongue, compressing the vallecula, structurally compatible with glossoptosis. This autopsy surpassed the scientific and epidemiological relevance, allowing the family genetic counseling and close monitoring of a subsequent pregnancy.

RESUMOSequência de Pierre Robin é uma doença neonatal caracterizada por micrognatismo, glossoptose e fenda palatina. Relatamos um caso de autópsia de uma criança cujas malformações da orofaringe somente foram identificadas ao nascimento. A criança era pré-termo extremo com depressão neonatal grave e má recuperação, e as malformações orofaciais impediram o correto tratamento. Havia alteração facial caracterizada por micrognatia associada a fenda palatina e posteriorização da língua, comprimindo a valécula, estruturalmente compatível com glossoptose. A autópsia extrapola as relevâncias científica e epidemiológica, permitindo o aconselhamento genético familiar e o monitoramento adequado da gestação subsequente.

The Th17 pathway in the peripheral lung microenvironment interacts with expression of collagen V in the late state of experimental pulmonary fibrosis.

BACKGROUND: Myofibroblasts derived from fibroblasts in the pathogenesis of pulmonary fibrosis causes excessive and disordered deposition of matrix proteins, including collagen V, which can cause a Th17-mediated immune response and lead to apoptosis. However, whether the intrinsic ability of lung FBs to produce the matrix depends on their site-specific variations is not known. AIM: To investigate the link between Th17 and collagen V that maintains pulmonary remodeling in the peripheral lung microenvironment during the late stage of experimental pulmonary fibrosis. METHODS: Young male mice including wild Balb/c mice (BALB, n=10), wild C57 Black/6J mice (C57, n=10) and IL-17 receptor A knockout mice (KO, n=8), were sacrificed 21 days after treatment with bleomycin. Picrosirius red staining, immunohistochemistry for IL-17-related markers and "in situ" detection of apoptosis, immunofluorescence for collagen types I and V, primary cell cultures from tissue lung explants for RT-PCR and electron microscopy were used. RESULTS: The peripheral deposition of extracellular matrix components by myofibroblasts during the late stage is maintained in C57 mice compared with that in Balb mice and is not changed in the absence of IL-17 receptor A; however, the absence of IL-17 receptor A induces overexpression of type V collagen, amplifies the peripheral expression of IL-17 and IL-17-related cytokines and reduces peripheral lung fibroblast apoptosis. CONCLUSION: A positive feedback loop between the expression patterns of collagen V and IL-17 may coordinate the maintenance of peripheral collagen I in the absence of IL-17 receptor A in fibrosis-susceptible strains in a site-specific manner.

Undergraduate research in medical education: a descriptive study of students' views.

BACKGROUND: Medical students engage in curricular and extracurricular activities, including undergraduate research (UR). The advantages, difficulties and motivations for medical students pursuing research activities during their studies have rarely been addressed. In Brazil, some medical schools have included undergraduate research into their curriculum. The present study aimed to understand the reality of scientific practice among medical students at a well-established Brazilian medical school, analyzing this context from the students' viewpoint. METHODS: A cross-sectional survey based on a questionnaire applied to students from years one to six enrolled in an established Brazilian medical school that currently has no curricular UR program. RESULTS: The questionnaire was answered by 415 students, 47.2% of whom were involved in research activities, with greater participation in UR in the second half of the course. Independent of student involvement in research activities, time constraints were cited as the main obstacle to participation. Among students not involved in UR, 91.1% said they favored its inclusion in the curriculum, since this would facilitate the development of such activity. This approach could signify an approximation between the axes of teaching and research. Among students who had completed at least one UR project, 87.7% said they would recommend the activity to students entering the course. CONCLUSION: Even without an undergraduate research program, students of this medical school report strong involvement in research activities, but discussion of the difficulties inherent in its practice is important to future developments.