The spectrum of morphological findings in pediatric central nervous system MN1-fusion-positive neuroepithelial tumors.

PURPOSE: Central nervous system high-grade neuroepithelial tumor with MN1 alteration (CNS-HGNET-MN1) is a rare entity defined by its DNA methylation pattern and pathologically considered to be high-grade with mixed patterns, stromal hyalinization, and with astrocytic differentiation. Our aim was to present six pediatric cases to contribute to the characterization of this group of tumors. MATERIAL AND METHODS: Six female patients aged 4 to 12 years with CNS tumors with MN1 alteration identified using genome-wide methylation arrays and/or RT-PCR were included. Clinicopathological, morphological, immunohistochemical, and molecular findings were analyzed. RESULTS: Tumor location was the parietal lobe in four and the intramedullary spinal cord in two. Two were morphologically diagnosed as ependymomas, one as gliofibroma, one as a HGNET-MN1 altered and the other two were difficult to classify. All were well-defined tumors, with a cystic component in three. Only two tumors had extensive stromal hyalinization, three had pseudopapillary formations, and four had other patterns. Multinucleated, clear, and rhabdoid cells were present. Necrosis and histiocyte clusters were also observed. Proliferative index was >10 in four. GFAP, EMA, CK, and SYN were variable, while Olig2 staining was mostly positive. Four of six patients with supratentorial tumors and complete resections were alive and tumor free after 2 to 10 years of follow-up. The two cases with medullary involvement and incomplete resections were alive and undergoing treatment 2 years after surgery. CONCLUSION: Neuroepithelial-MN1 tumors are challenging and suspicion requires molecular confirmation. Our pediatric data contribute to the knowledge for accurate diagnosis. Although further studies with a larger number of cases should be conducted in order to draw more robust conclusions regarding clinico-pathological features, here we present valuable pediatric data to increase the knowledge that may lead to the accurate management of this group of tumors.

A Single Dose of a Hybrid hAdV5-Based Anti-COVID-19 Vaccine Induces a Long-Lasting Immune Response and Broad Coverage against VOC.

Most approved vaccines against COVID-19 have to be administered in a prime/boost regimen. We engineered a novel vaccine based on a chimeric human adenovirus 5 (hAdV5) vector. The vaccine (named CoroVaxG.3) is based on three pillars: (i) high expression of Spike to enhance its immunodominance by using a potent promoter and an mRNA stabilizer; (ii) enhanced infection of muscle and dendritic cells by replacing the fiber knob domain of hAdV5 by hAdV3; (iii) use of Spike stabilized in a prefusion conformation. The transduction with CoroVaxG.3-expressing Spike (D614G) dramatically enhanced the Spike expression in human muscle cells, monocytes and dendritic cells compared to CoroVaxG.5 that expressed the native fiber knob domain. A single dose of CoroVaxG.3 induced a potent humoral immunity with a balanced Th1/Th2 ratio and potent T-cell immunity, both lasting for at least 5 months. Sera from CoroVaxG.3-vaccinated mice was able to neutralize pseudoviruses expressing B.1 (wild type D614G), B.1.117 (alpha), P.1 (gamma) and B.1.617.2 (delta) Spikes, as well as an authentic P.1 SARS-CoV-2 isolate. Neutralizing antibodies did not wane even after 5 months, making this kind of vaccine a likely candidate to enter clinical trials.

[Neurology and COVID-19: Case Series of Neurological Complications in 96 patients Admitted at a University Hospital]. / Neurología hospitalaria y COVID-19: serie de 96 pacientes evaluados en un hospital universitario.

BACKGROUND: There are multisystemic consequences secondary to SARS- CoV-2 infection. AIM: To characterize neurological complications in patients admitted due to SARS-CoV-2 infection. METHODS: Review of medical records of patients aged over 15 years with COVID-19 evaluated by the neurology team between April and August 2020 at a university hospital. Severity of the infection, referral reasons, neurological diagnoses and laboratory results were registered. The diagnoses were defined by consensus among the members of the hospital neurology group. Cerebrovascular and inflammatory diseases of the central and peripheral nervous system were defined as "probably associated" or "possibly associated" to COVID-19. RESULTS: Ninety-six patients had at least 1 new neu- rological complication. 74% were admitted due to pneumonia and 20% due to a neurological disease. The most common reasons for neurological referral were impaired consciousness (39%), focal neurological deficit (24%), headache (9%) and seizures (5%). The most relevant neurological diagnoses were delirium in 48 patients, stroke in 24, critical illness polyneuropathy and myopathy in 17, seizures in 14, brachial plexopathy in 3, compressive neuropathies in 5, encephalitis in 1, possible vasculitis in 1 and Guillain-Barré syndrome in 1. Stroke and epilepsy were associated with increased length of hospital stay, but without differences in mortality. CONCLUSIONS: The spectrum of neurological complications of COVID-19 is wide. There are clinical entities typical of critically ill patients and also diseases associated directly and indirectly with the SARS-CoV2 infection.

Neurología hospitalaria y COVID-19: serie de 96 pacientes evaluados en un hospital universitario / Neurology and COVID-19: Case Series of Neurological Complications in 96 patients Admitted at a University Hospital

Background: There are multisystemic consequences secondary to SARS- CoV-2 infection. Aim: To characterize neurological complications in patients admitted due to SARS-CoV-2 infection. Methods: Review of medical records of patients aged over 15 years with COVID-19 evaluated by the neurology team between April and August 2020 at a university hospital. Severity of the infection, referral reasons, neurological diagnoses and laboratory results were registered. The diagnoses were defined by consensus among the members of the hospital neurology group. Cerebrovascular and inflammatory diseases of the central and peripheral nervous system were defined as "probably associated" or "possibly associated" to COVID-19. Results: Ninety-six patients had at least 1 new neu- rological complication. 74% were admitted due to pneumonia and 20% due to a neurological disease. The most common reasons for neurological referral were impaired consciousness (39%), focal neurological deficit (24%), headache (9%) and seizures (5%). The most relevant neurological diagnoses were delirium in 48 patients, stroke in 24, critical illness polyneuropathy and myopathy in 17, seizures in 14, brachial plexopathy in 3, compressive neuropathies in 5, encephalitis in 1, possible vasculitis in 1 and Guillain-Barré syndrome in 1. Stroke and epilepsy were associated with increased length of hospital stay, but without differences in mortality. Conclusions: The spectrum of neurological complications of COVID-19 is wide. There are clinical entities typical of critically ill patients and also diseases associated directly and indirectly with the SARS-CoV2 infection.

Efectos de la actividad locomotriz voluntaria gestacional sobre la morfología cardiaca en crías murinas / Effects of gestational voluntary locomotor activity on cardiac morphology in murine offspring

RESUMEN: El objetivo del presente estudio es analizar los efectos de la actividad locomotriz voluntaria gestacional, como un tipo de entrenamiento físico, sobre la morfología de la bomba cardíaca de la cría, en modelo murino de la cepa CF-1. 12 hembras gestantes fueron divididas aleatoriamente en un grupo control y un grupo que realizó actividad locomotriz voluntaria, accediendo a una rueda de actividad durante los primero 12 días de gestación. Se evaluó la morfología cardiaca mediante cortes transversales, midiendo espesor y área de las paredes del ventrículo derecho, ventrículo izquierdo y septum, tanto en valores absolutos como en valores relativos a la masa corporal del individuo. Se observó que la masa corporal de las crías control (GC) fue significativamente mayor que las del grupo cuyas hembras accedieron a la rueda de actividad (GE) (p<0.01). Solo hubo diferencias en los valores absolutos de espesores y áreas miocárdicas de ventrículo derecho, entre el grupo GE y GC (p<0.05), pero al evaluar los espesores y áreas relativos a la masa corporal se observó que las crías del grupo GE presentaron espesores y áreas significativamente mayores que las que grupo GC (p<0.01). En conclusión, la actividad física gestacional altera el desarrollo morfológico de la bomba cardíaca en ratones CF-1, aumentando significativamente el espesor y área de las paredes miocárdicas en relación a la masa corporal total de la cría.

SUMMARY: The objective of the present study is to analyze the effects of gestational voluntary locomotor activity, as a type of physical training, on the morphology of the offspring´s heart pump, in a murine model of the CF-1 strain. Twelve (12) pregnant females were randomly divided in a control group and a group performing voluntary locomotor activity, by accessing an activity wheel during the first 12 days of gestation. Cardiac morphology was evaluated using cross sections, measuring thickness and area of the walls of the right ventricle, left ventricle, and septum, both in absolute values and values relative to the individual's body mass. It was observed that the body mass of the control pups (CG) was significantly higher than those of the group whose females accessed the activity wheel (GE) (p <0.01). Differences were observed only in absolute values of thickness and myocardial areas of the right ventricle, between the GE and GC group (p <0.05). However, when evaluating the thickness and areas relative to body mass, it was observed that the offspring of the GE group presented thicknesses and areas significantly larger than those in the GC group (p <0.01). In conclusion, gestational physical activity alters the morphological development of the heart pump in CF-1 mice, significantly increasing the thickness and area of the myocardial walls in relation to offspring total body mass.

Application of Synthetic Tumor-Specific Promoters Responsive to the Tumor Microenvironment.

Activity of endogenous promoters can be altered by including additional responsive elements (REs). These elements can be responsive to features of the tumor environment or alternatively to signaling pathways specifically activated in cancer cells. These REs incorporated into tumor-specific promoters can improve cancer targeting, the replicative capacity, and lytic activity of conditionally replicative adenovirus. Here we outline an approach to incorporate hypoxia and inflammation REs into a specific fragment of the SPARC promoter and the steps to clone a nucleosome positioning sequence (NPS ) identified in the osteocalcin promoter that contains a Wnt RE upstream of a heterologous synthetic promoter.

Geographic latitude and sleep duration: A population-based survey from the Tropic of Capricorn to the Antarctic Circle.

The impact of latitude on sleep duration remains virtually unexplored, even though latitude exerts profound influences on daylight duration. Using Chile as a one-country model, we explored on the potential associations between sleep duration and latitude. Based on the 2nd Chilean Health Survey, we identified reported sleep data during spring of people living from north to south in Chilean cities, located between 18°29'S to 53°18'S (4329 km distance at same longitude). A total of n = 2493 participants were included (mean age 45.3 ± 18.4 years, 41.8% males). Mean sleep duration on workdays and weekends was 7.42 ± 1.71 h, and 7.91 ± 2.13 h, respectively, ranging from 7.91 ± 1.92 h in the north to 8.33 ± 1.89 h in the south, such that more northern latitudes (i.e., 18°29'S to 39°50'S) slept less compared to more southern latitudes (i.e., 51°43'S-53°18'), even after controlling for age, gender, and socioeconomic status. In the logistic regression models, men residing at northern latitudes exhibited an odds ratio of 3.348 [95% CI: 1.905-5.882; p < 0.0001] for having shorter sleep on weekends than their southern counterparts. Latitude appears to strongly affect reported sleep patterns, leading to longer sleep duration with increasing latitude, particularly in men during weekends. Whether environmental factors such as photoperiod are causally involved in theses associations needs to be elucidated in future studies.

[Human papillomavirus testing in cervical cancer screening at a public health service of Santiago, Chile]. / Examen de detección de virus papiloma humano en el tamizaje de cáncer cervicouterino en un Servicio de Salud de Santiago, Chile.

BACKGROUND: Molecular techniques for human papillomavirus (HPV) detection have a good performance as screening tests and could be included in cervical cancer early detection programs. We conducted a population-based trial comparing HPV detection and Papanicolaou as primary screening tests, in a public health service in Santiago, Chile. AIM: To describe the experience of implementing this new molecular test and present the main results of the study. MATERIAL AND METHODS: Women aged 25 to 64 enrolled in three public health centers were invited to participate. In all women, samples were collected for Papanicolaou and HPV DNA testing, and naked-eye visual inspection of the cervix with acetic acid was performed. Women with any positive screening test were referred to the local area hospital for diagnostic confirmation with colposcopy and biopsy of suspicious lesions. RESULTS: Screening results were obtained for 8265 women, of whom 931 (11.3%) were positive to any test. The prevalence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was 1.1%; nine women had invasive cervical cancer. Sensitivities for the detection of CIN2+ were 22.1% (95% confidence interval (CI) 16.4-29.2) for Papanicolaou and 92.7% (95% CI 84.4-96.8) for HPV testing; specificities were 98.9% (95% CI 98.7-99.0) and 92.0% (95% CI 91.4-92.6) respectively. CONCLUSION: This experience showed that the implementation of a molecular test for cervical cancer screening is not a major challenge in Chile: it was well accepted by both the health team and the participants, and it may improve the effectiveness of the screening program.

Examen de detección de virus papiloma humano en el tamizaje de cáncer cervicouterino en un Servicio de Salud de Santiago, Chile / Human papillomavirus testing in cervical cancer screening at a public health service of Santiago, Chile

Background: Molecular techniques for human papillomavirus (HPV) detection have a good performance as screening tests and could be included in cervical cancer early detection programs. We conducted a population-based trial comparing HPV detection and Papanicolaou as primary screening tests, in a public health service in Santiago, Chile. Aim: To describe the experience of implementing this new molecular test and present the main results of the study. Material and Methods: Women aged 25 to 64 enrolled in three public health centers were invited to participate. In all women, samples were collected for Papanicolaou and HPV DNA testing, and naked-eye visual inspection of the cervix with acetic acid was performed. Women with any positive screening test were referred to the local area hospital for diagnostic confirmation with colposcopy and biopsy of suspicious lesions. Results: Screening results were obtained for 8265 women, of whom 931 (11.3%) were positive to any test. The prevalence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) was 1.1%; nine women had invasive cervical cancer. Sensitivities for the detection of CIN2+ were 22.1% (95% confidence interval (CI) 16.4-29.2) for Papanicolaou and 92.7% (95% CI 84.4-96.8) for HPV testing; specificities were 98.9% (95% CI 98.7-99.0) and 92.0% (95% CI 91.4-92.6) respectively. Conclusion: This experience showed that the implementation of a molecular test for cervical cancer screening is not a major challenge in Chile: it was well accepted by both the health team and the participants, and it may improve the effectiveness of the screening program.

Enhanced CRAd activity using enhancer motifs driven by a nucleosome positioning sequence.

Cancer development involves changes driven by the epigenetic machinery, including nucleosome positioning. Recently, the concept that adenoviral replication may be driven by tumor specific promoters (TSPs) gained support, and several conditionally replicative adenoviruses (CRAd) exhibited therapeutic efficacy in clinical trials. Here, we show for the first time that placing a nucleosome positioning sequence (NPS) upstream of a TSP combined with Wnt-responsive motifs (pART enhancer) enhanced the TSP transcriptional activity and increased the lytic activity of a CRAd. pART enhanced the transcriptional activity of the gastrointestinal cancer (GIC)-specific REG1A promoter (REG1A-pr); moreover, pART also increased the in vitro lytic activity of a CRAd whose replication was driven by REG1A-Pr. The pART enhancer effect in vitro and in vivo was strictly dependent on the presence of the NPS. Indeed, deletion of the NPS was strongly deleterious for the in vivo antitumor efficacy of the CRAd on orthotopically established pancreatic xenografts. pART also enhanced the specific activity of other heterologous promoters; moreover, the NPS was also able to enhance the responsiveness of hypoxia- and NFκB-response elements. We conclude that NPS could be useful for gene therapy approaches in cancer as well as other diseases.

Screening trial of human papillomavirus for early detection of cervical cancer in Santiago, Chile.

Cervical cancer mortality in Chile is four times higher than in developed countries. We compared the accuracy of human papillomavirus (HPV) DNA testing and conventional Papanicolaou (Pap) testing to detect prevalent precancerous and cancerous lesions in the routine clinical practice of the public health system. Women aged 25 years and older residing in the area covered by three primary care centers of Santiago, Chile, were invited to participate. Eligible women received both HPV DNA (Hybrid Capture 2) and Pap testing. Women positive by either test (Pap: ASCUS+, HC2: RLU/CO ≥ 1.0) underwent colposcopy and biopsy, as did a sample of double-negative women with an abnormal cervix at visual inspection or with risk factors for cervical lesions. Crude and verification bias-corrected sensitivities and specificities were estimated. In total, 8,265 women (98.8% of eligible) had complete screening results. Of these, 10.7% were HPV positive, 1.7% were Pap positive and 1.1% were positive by both tests. In all, 931 (11.3%) women were screen-positive, of whom 94.3% attended colposcopy. Additionally, 295 control women were invited for colposcopy, of whom 78% attended. In all, 42 CIN2, 45 CIN3 and 9 cancers were identified. Verification bias-corrected sensitivity for CIN2+ (95% confidence interval) was 92.7% (84.4-96.8) for HPV and 22.1% (16.4-29.2) for Pap; corresponding specificities were 92.0% (91.4-92.6) and 98.9% (98.7-99.0). In conclusion, in routine clinical practice in a developing country, HPV testing was four times more sensitive for CIN2+ than Pap testing, identifying three times more CIN2+ lesions; HPV testing was easily implemented in our established cervical cancer prevention program.

Wnt/ß-catenin signaling enhances cyclooxygenase-2 (COX2) transcriptional activity in gastric cancer cells.

BACKGROUND: Increased expression of the cyclooxygenase-2 enzyme (COX2) is one of the main characteristics of gastric cancer (GC), which is a leading cause of death in the world, particularly in Asia and South America. Although the Wnt/ß-catenin signaling pathway has been involved in the transcriptional activation of the COX2 gene, the precise mechanism modulating this response is still unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we studied the transcriptional regulation of the COX2 gene in GC cell lines and assessed whether this phenomenon is modulated by Wnt/ß-catenin signaling. We first examined the expression of COX2 mRNA in GC cells and found that there is a differential expression pattern consistent with high levels of nuclear-localized ß-catenin. Pharmacological treatment with either lithium or valproic acid and molecular induction with purified canonical Wnt3a significantly enhanced COX2 mRNA expression in a dose- and time-dependent manner. Serial deletion of a 1.6 Kbp COX2 promoter fragment and gain- or loss-of-function experiments allowed us to identify a minimal Wnt/ß-catenin responsive region consisting of 0.8 Kbp of the COX2 promoter (pCOX2-0.8), which showed maximal response in gene-reporter assays. The activity of this pCOX2-0.8 promoter region was further confirmed by site-directed mutagenesis and DNA-protein binding assays. CONCLUSIONS/SIGNIFICANCE: We conclude that the pCOX2-0.8 minimal promoter contains a novel functional T-cell factor/lymphoid enhancer factor (TCF/LEF)-response element (TBE Site II; -689/-684) that responds directly to enhanced Wnt/ß-catenin signaling and which may be important for the onset/progression of GC.

[Undergraduate medical students' expectative of their desired profile as medical doctors]. / Expectativas de estudiantes de medicina de pregrado en relación al perfil de médico esperado.

BACKGROUND: During the last few years, multiple new medical schools have emerged in Chile, associated to the constant preoccupation to provide a good quality medical care. This created the need to evaluate medical training programs and to open a discussion about the attributes that a good physician should have. AIM: To evaluate the medical student's perception of the ideal medical doctor profile. MATERIAL AND METHODS: An analytical, descriptive and cross sectional study was designed. Eleven second year, 11 third year, nine fourth year, 13 fifth year, 6 sixth year and 8 seventh year students were studied. Data collection was gathered by focus groups. Codes and triangulation were used for data analysis. RESULTS: As attitudes and moral-ethical values, students valued the absence of discrimination a listening attitude and empathy. Among job related issues, they valued responsibility and punctuality. Emotional and legal self-care were valued as self related attitudes. Among skills, competences and capacities, a value was given to communicational skills, team work and professional easiness. Knowledge about medical and non medical topics was appraised. The valued attributes among duties and activities were patient diagnosis, treatment and education, team leadership and continuous medical training. CONCLUSIONS: These findings should help to design new curricula for medical schools.

[Human immunodeficiency virus (HIV) infection in pregnancy: antiretroviral treatment (ART) and mode of delivery]. / Infección por virus de inmunodeficiencia humana en el embarazo: tratamiento anti-retroviral y vía de parto.

Antiretroviral therapy (ART) administered to pregnant women infected with HIV diminishes the rate of perinatal viral transmission. This is true for mono-, bi-, or tri-therapy (HAART), with the greatest effects being seen in the latter case. Nevertheless, when these therapies are employed, potential risks to the mother and fetus must be considered. These risks include hyperglycemia, lactic acidosis, mitochondrial toxicity, cutaneous rash, hepatitis, hypertension, and premature labor. Elective caesarean section reduces the perinatal transmission of HIV in patients with or without monotherapy, but has not shown a benefit in patients on tri-therapy (HAART). This article reviews the evidence for and against antiretroviral therapy and elective caesarean section in the setting of HIV in pregnancy and proposes treatment guidelines for these patients.

Utilización de un índice clínico-ecográfico para la clasificación de los tumores de ovario

Diseñar un método que seleccione con cierta confiabilidad entre tumores benignos y malignos, de estos últimos poder seleccionar cuales verdaderamente requieren otros exámenes complementarios o de extensión