Interim 18F-FDG-PET based response-adaptive dose escalation of proton therapy for head and neck cancer: a treatment planning feasibility study.

BACKGROUND: Image-driven dose escalation to tumor subvolumes has been proposed to improve treatment outcome in head and neck cancer (HNC). We used 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) acquired at baseline and into treatment (interim) to identify biologic target volumes (BTVs). We assessed the feasibility of interim dose escalation to the BTV with proton therapy by simulating the effects to organs at risk (OARs). METHODS: We used the semiautomated just-enough-interaction (JEI) method to identify BTVs in 18F-FDG-PET images from nine HNC patients. Between baseline and interim FDG-PET, patients received photon radiotherapy. BTV was identified assuming that high standardized uptake value (SUV) at interim reflected tumor radioresistance. Using Eclipse (Varian Medical Systems), we simulated a 10% (6.8 Gy(RBE1.1)) and 20% (13.6 Gy(RBE1.1)) dose escalation to the BTV with protons and compared results with proton plans without dose escalation. RESULTS: At interim 18F-FDG-PET, radiotherapy resulted in reduced SUV compared to baseline. However, spatial overlap between high-SUV regions at baseline and interim allowed for BTV identification. Proton therapy planning demonstrated that dose escalation to the BTV was feasible, and except for some 20% dose escalation plans, OAR doses did not significantly increase. CONCLUSION: Our in silico analysis demonstrated the potential for interim 18F-FDG-PET response-adaptive dose escalation to the BTV with proton therapy. This approach may give more efficient treatment to HNC with radioresistant tumor subvolumes without increasing normal tissue toxicity. Studies in larger cohorts are required to determine the full potential for interim 18F-FDG-PET-guided dose escalation of proton therapy in HNC.

Mechanistic insights into G-protein coupling with an agonist-bound G-protein-coupled receptor.

G-protein-coupled receptors (GPCRs) activate heterotrimeric G proteins by promoting guanine nucleotide exchange. Here, we investigate the coupling of G proteins with GPCRs and describe the events that ultimately lead to the ejection of GDP from its binding pocket in the Gα subunit, the rate-limiting step during G-protein activation. Using molecular dynamics simulations, we investigate the temporal progression of structural rearrangements of GDP-bound Gs protein (Gs·GDP; hereafter GsGDP) upon coupling to the ß2-adrenergic receptor (ß2AR) in atomic detail. The binding of GsGDP to the ß2AR is followed by long-range allosteric effects that significantly reduce the energy needed for GDP release: the opening of α1-αF helices, the displacement of the αG helix and the opening of the α-helical domain. Signal propagation to the Gs occurs through an extended receptor interface, including a lysine-rich motif at the intracellular end of a kinked transmembrane helix 6, which was confirmed by site-directed mutagenesis and functional assays. From this ß2AR-GsGDP intermediate, Gs undergoes an in-plane rotation along the receptor axis to approach the ß2AR-Gsempty state. The simulations shed light on how the structural elements at the receptor-G-protein interface may interact to transmit the signal over 30 Å to the nucleotide-binding site. Our analysis extends the current limited view of nucleotide-free snapshots to include additional states and structural features responsible for signaling and G-protein coupling specificity.

Thermal Reactivation of Hydrated Cement Paste: Properties and Impact on Cement Hydration.

In this research, the properties and cementitious performance of thermally activated cement pastes (referred to as DCPs) are investigated. Hydrated pastes prepared from Portland cement and slag blended cement were subjected to different thermal treatments: 350 °C for 2 h, 550 °C for 2 h, 550 °C for 24 h and 750 °C for 2 h. The properties and the reactivity as SCM of the DCPs were characterised as well as their effect on the mechanical performance and hydration of new blended cements incorporating the DCPs as supplementary cementitious materials (SCMs). It was observed that the temperature and duration of the thermal treatment increased the grindability and BET specific surface area of the DCP, as well as the formation of C2S phases and the reactivity as SCM. In contrast, the mechanical strength results for the blended cements indicated that thermal treatment at 350 °C for 2 h provided better performance. The hydration study results showed that highly reactive DCP interfered with the early hydration of the main clinker phases in Portland cement, leading to early setting and slow strength gain. The effect on blended cement hydration was most marked for binary Portland cement-DCP blends. In contrast, in the case of ternary slag cement-DCP blends the use of reactive DCP as SCM enabled to significantly increase early age strength.

Machine Learning-Based Prediction of Cattle Activity Using Sensor-Based Data.

Livestock monitoring is a task traditionally carried out through direct observation by experienced caretakers. By analyzing its behavior, it is possible to predict to a certain degree events that require human action, such as calving. However, this continuous monitoring is in many cases not feasible. In this work, we propose, develop and evaluate the accuracy of intelligent algorithms that operate on data obtained by low-cost sensors to determine the state of the animal in the terms used by the caregivers (grazing, ruminating, walking, etc.). The best results have been obtained using aggregations and averages of the time series with support vector classifiers and tree-based ensembles, reaching accuracies of 57% for the general behavior problem (4 classes) and 85% for the standing behavior problem (2 classes). This is a preliminary step to the realization of event-specific predictions.

Time-resolved cryo-EM of G-protein activation by a GPCR.

G-protein-coupled receptors (GPCRs) activate heterotrimeric G proteins by stimulating guanine nucleotide exchange in the Gα subunit1. To visualize this mechanism, we developed a time-resolved cryo-EM approach that examines the progression of ensembles of pre-steady-state intermediates of a GPCR-G-protein complex. By monitoring the transitions of the stimulatory Gs protein in complex with the ß2-adrenergic receptor at short sequential time points after GTP addition, we identified the conformational trajectory underlying G-protein activation and functional dissociation from the receptor. Twenty structures generated from sequential overlapping particle subsets along this trajectory, compared to control structures, provide a high-resolution description of the order of main events driving G-protein activation in response to GTP binding. Structural changes propagate from the nucleotide-binding pocket and extend through the GTPase domain, enacting alterations to Gα switch regions and the α5 helix that weaken the G-protein-receptor interface. Molecular dynamics simulations with late structures in the cryo-EM trajectory support that enhanced ordering of GTP on closure of the α-helical domain against the nucleotide-bound Ras-homology domain correlates with α5 helix destabilization and eventual dissociation of the G protein from the GPCR. These findings also highlight the potential of time-resolved cryo-EM as a tool for mechanistic dissection of GPCR signalling events.

Discrimination/Classification of Edible Vegetable Oils from Raman Spatially Solved Fingerprints Obtained on Portable Instrumentation.

Currently, the combination of fingerprinting methodology and environmentally friendly and economical analytical instrumentation is becoming increasingly relevant in the food sector. In this study, a highly versatile portable analyser based on Spatially Offset Raman Spectroscopy (SORS) obtained fingerprints of edible vegetable oils (sunflower and olive oils), and the capability of such fingerprints (obtained quickly, reliably and without any sample treatment) to discriminate/classify the analysed samples was evaluated. After data treatment, not only unsupervised pattern recognition techniques (as HCA and PCA), but also supervised pattern recognition techniques (such as SVM, kNN and SIMCA), showed that the main effect on discrimination/classification was associated with those regions of the Raman fingerprint related to free fatty acid content, especially oleic and linoleic acid. These facts allowed the discernment of the original raw material used in the oil's production. In all the models established, reliable qualimetric parameters were obtained.

Carcinosarcoma uterino presentándose como masa cervical ­ reporte de un caso

El carcinosarcoma es un tumor poco frecuente que se presenta principalmente en el tracto genital femenino. Su característica más importante es la presencia sincrónica de un componente epitelial maligno (carcinoma) y un componente mesenquimal maligno (sarcoma). Estudios recientes demuestran que la mayoría de las veces el componente sarcomatoso se origina de una diferenciación metaplásica del componente epitelial. Debido a su poca frecuencia, no se conoce con certeza la relación entre las distintas presentaciones histológicas con los posibles factores de riesgo asociados, el pronóstico y la respuesta terapéutica. En este trabajo se reportaron las características histopatológicas y la expresión inmunohistoquímica de un caso de carcinosarcoma uterino en una paciente de 73 años que se presentó inicialmente como una masa cervical. El patrón microscópico documentado fue el de un tumor epitelial de bajo grado asociado a un componente mesenquimal con diferenciación rabdomiosarcomatosa (inmunohistoquímica positiva para desmina y miogenina). La documentación fenotípica es importante para en un futuro desarrollar posibles opciones terapéuticas dirigidas a los distintos patrones histológicos y determinar su posible asociación con factores de riesgo. (provisto por Infomedic International)

Carcinosarcoma is a rare tumor occurring mainly in the female genital tract. Its most important characteristic is the synchronous presence of a malignant epithelial component (carcinoma) and a malignant mesenchymal component (sarcoma). Recent studies show that most of the time the sarcomatous component originates from a metaplastic differentiation of the epithelial component. Due to its infrequency, the relationship between the different histologic presentations with possible associated risk factors, prognosis and therapeutic response is not known with certainty. In this paper we report the histopathologic features and immunohistochemical expression of a case of uterine carcinosarcoma in a 73-year-old female patient who initially presented as a cervical mass. The microscopic pattern documented was that of a low-grade epithelial tumor associated with a mesenchymal component with rhabdomyosarcomatous differentiation (positive immunohistochemistry for desmin and myogenin). Phenotypic documentation is important for future development of possible therapeutic options targeting the different histologic patterns and determining their possible association with risk factors. (provided by Infomedic International)

Ictericia obstructiva secundaria a un pseudoaneurisma de arteria mesentérica superior / Obstructive jaundice secondary to a pseudoaneurysm of the superior mesenteric artery

Los pseudoaneursimas de arteria mesentérica superior son una entidad rara, generalmente asintomáticos pero que pueden debutar con dolor abdominal, masa pulsátil o shock, siendo excepcional la ictericia como forma de presentación. El diagnóstico se realiza mediante pruebas de imagen (TC) y en la actualidad el abordaje endovascular es el más extendido reservándose la cirugía abierta en casos seleccionados. Describimos el caso de una paciente con un pseudoaneurisma de la AMS de 86mm con compresión de la vía biliar extrahepática. (AU)

Linfoma de Hodgkin anal primario y tumor neuroendocrino intestinal sincrónicos: a propósito de un caso y revisión de la literatura / Primary rectal Hodgkin's lymphoma and synchronous small bowel neuroendocrine tumor: Case report and literature review

Resumen La localización extranodal gastrointestinal del linfoma de Hodgkin comprende el 5% de todos los linfomas. Dentro de este grupo, el linfoma anal primario representa menos del 0,05%, siendo por tanto una entidad extremadamente rara. Por otro lado, los tumores neuroendocrinos son un grupo heterogéneo de neoplasias relativamente poco frecuentes, pero de localización fundamentalmente digestiva. La asociación entre un linfoma de Hodgkin de localización anal y un tumor neuroendocrino intestinal no ha sido descrita previamente en la literatura, pero no es en absoluto raro que los tumores neuroendocrinos puedan coexistir con otro tipo de neoplasias. Los autores presentan el caso infrecuente de presentación de linfoma Hodgkin de localización anal asociado a un tumor neuroendocrino intestinal en una paciente mujer de 74 años, describiéndose la clínica, resultados de pruebas complementarias y tratamiento recibido.

Abstract Extranodal gastrointestinal Hodgkin's lymphoma comprises 5% of all lymphomas. In this group, primary rectal lymphoma represents less than 0.05%; thus, it is an extremely rare entity. On the other hand, neuroendocrine tumors are a heterogeneous group of infrequent neoplasms, mainly of digestive location. The association between a rectal Hodgkin's lymphoma and an intestinal neuroendocrine tumor has not been previously described in the literature, but it is not at all uncommon for neuroendocrine tumors to coexist with other types of neoplasms. The authors present a rare case of rectal Hodgkin's lymphoma associated with an intestinal neuroendocrine tumor in a 74-year-old female patient, describing the symptoms, complementary test results, and treatment.

Follow-up to the baby friendly hospital initiative in two hospitals of the Mexican Social Security Institute / Seguimiento de la iniciativa hospital amigo del niño y la niña en dos hospitales del Instituto Mexicano del Seguro Social

Abstract Background: The Baby Friendly Hospital Initiative has proven to be effective to increase exclusive and prolonged breastfeeding. Material and methods: Longitudinal study, in two hospitals of second level, in the period from 2015 to 2018. A percentage above 85% in each step was considered acceptable. The statistical analysis was descriptive using student's t test to compare the mean between the two hospitals and ANOVA to compare the mean throughout time in SPSS v.25. Results: Steps 1 and 7 were different between the hospitals with p = 0.010 and p = 0.023, respectively. In the follow-up, General Zone Hospital No. 5 kept steps 1, 2, 3, 7, 8, and 9 above 85%, while those who did not were steps 4, 5, 6, and 10, p = 0.37. Steps of General Hospital No. 15 that remained over 85% were 1, 3, 7, and 9; those that oscillated over time with a <85% rating were steps 2, 4, 5, 6, 8, and 10, p = 0.003. Conclusion: Monitoring child-friendly hospitals allow us to observe areas of opportunity to strengthen training for both clinical and non-clinical staff, pregnant women, the general population, and to improve exclusive and prolonged breastfeeding.

Resumen Introducción: La Iniciativa Hospital Amigo del Niño y la Niña ha probado ser efectiva para mejorar la lactancia materna exclusiva y prolongada. Material y métodos: Estudio longitudinal, en dos hospitales de segundo nivel, en el periodo de 2015 a 2018. Un porcentaje superior al 85% en cada paso se consideró aceptable. El análisis estadístico fue descriptivo, utilizando la prueba t de Student para comparar las medias entre los dos hospitales y el análisis de la varianza para compararlas a lo largo del tiempo empleando el programa SPSS v.25. Resultados: Los pasos 1 y 7 variaron entre los hospitales (con p = 0.010 y p = 0.023, respectivamente). En el seguimiento, el Hospital General de Zona (HGZ) 5 mantuvo los pasos 1, 2, 3, 7, 8 y 9 por encima del 85%, y < 85% los pasos 4, 5, 6 y 10 (p = 0.37). Las medidas del HGZ 15 que se mantuvieron > 85% fueron 1, 3, 7 y 9; aquellos que oscilaron a lo largo del tiempo con una calificación < 85% fueron los pasos 2, 4, 5, 6, 8 y 10 (p = 0.003). Conclusión: Estos seguimientos permiten observar áreas de oportunidad para reforzar la capacitación al personal clínico y no clínico como a las mujeres embarazadas, a la población en general y para mejorar la lactancia materna exclusiva y prolongada.

Hemosuccus pancreaticus: rara asociación entre pancreatitis aguda, alcoholismo y sesiones vasculares en la circulación esplácnica / Hemosuccus Pancreaticus: an unusual association of acute pancreatitis, alcoholism and vascular abnormalities of the splanchnic circulation

La pancreatitis aguda o crónica puede resultar en lesiones del conducto pancreático, además, la corrosión por el jugo pancreático puede provocar la ruptura de la pared vascular periférica, lo que conduce a hemosuccus pancreático (HP) definido como el sangrado del conducto pancreático a través de la ampolla de Vater. El sangrado suele ser intermitente, repetitivo y, a menudo, no lo suficientemente grave, como para causar inestabilidad hemodinámica. La mayoría de los pacientes tiene antecedentes de enfermedades pancreáticas originales y cuando esto no se cumple, debe incluirse en el diagnóstico diferencial para alcohólicos crónicos con hemorragia digestiva alta intermitente. Presentamos una forma clínica atípica en un paciente masculino de 55 años de edad, con antecedentes de HTA, alcoholismo y aneurisma de la aorta abdominal, quien consultó por dolor tipo cólico en abdomen superior, náuseas y vómitos; luego se asoció disminución del estado de conciencia, alternando con episodios de agitación psicomotriz y primo convulsión generalizada. Una vez ingresado, sucedieron varios episodios de melena. La tomografía abdominal mostró aumento de tamaño y densidad (unidades hounsfield de 58-61) en cabeza y cuerpo del páncreas, por lo que se realizó una angiografía abdominal con protocolo de páncreas y se evidenció doble lesión aneurismática de la arteria esplénica y la arteria gástrica. Falleció en el postoperatorio(AU)

Acute or chronic pancreatitis can result in lesions of the pancreatic duct; in addition, corrosion by the pancreatic juice can cause the rupture of the peripheral vascular wall, which leads to pancreatic hemosuccus defined as bleeding from the pancreatic duct through the Vater ampulla. Bleeding is often intermittent, repetitive, and often not severe enough to cause hemodynamic instability. Most of the cases have a history of strictly pancreatic original diseases, when this is not the case, the PH should be included in the differential diagnosis for chronic alcoholics with intermittent upper gastrointestinal bleeding, We report here an atypical presentation in a 55-year-old male patient with a history of hypertension, alcoholism and an abdominal aortic aneurysm. He consulted for colicky abdominal pain in the upper abdomen, nausea and vomiting; subsequently he presented decreased consciousness, alternating with episodes of psychomotor agitation and generalized seizures. Once hospitalized he had several bouts of melena. The abdominal tomography showed an increase in the size and density (hounsfield units of 58-61) of the head and body of the pancreas. An abdominal angiography with a pancreas protocol was performed, which evidenced a double aneurismal lesion of the splenic and gastric arteries. The patient died after surgery(AU)

Linfoma MALT de localización colónica: a propósito de un caso y revisión de la literatura / Colonic MALT Lymphoma. Case report and literature review

Resumen El linfoma MALT es una forma poco frecuente de linfoma no Hodking de células B de bajo grado, que se desarrolla a expensas del tejido linfoide de las membranas mucosas. La localización más frecuente a nivel gastrointestinal es el estómago relacionando con la infección por Helicobacter pylori. El linfoma MALT colónico es una entidad extremadamente rara y cuya incidencia no supera el 5% de los casos en países asiáticos, con series porcentualmente menores al 2,5%, siendo la ubicación de este tipo de linfoma la más inusual de todo el tracto digestivo en comparación con otras neoplasias malignas que afectan al colon. Los autores exponen el caso infrecuente de presentación de linfoma tipo MALT de localización colónica en un paciente varón de 51 años, describiendo la clínica, los resultados de pruebas complementarias y el tratamiento recibido por el paciente.

Abstract MALT lymphoma is a rare form of low-grade non-Hodking B-cell lymphoma, which develops at the expense of lymphoid tissue of the mucous membranes. The most frequent location at the gastrointestinal level is the stomach related to the infection by Helicobacter pylori. Colonic MALT lymphoma is an extremely rare entity and the incidence of which does not exceed 5% of cases in Asian countries, with a series of less than 2.5%, with the location of this type of lymphoma being the most unusual of the entire digestive tract compared to other malignant neoplasms that affect the colon. The authors present the infrequent case of presentation of MALT-type lymphoma of colonic location in a 51-year-old male patient, describing the clinic, the results of complementary tests and the treatment received by the patient.

Salmonella enteritidis como causa de gangrena de Fournier / Fournier's gangrene caused by Salmonella enteritidis

La gangrena de Fournier es una fascitis necrotizante perineal grave atribuida a la acción sinérgica de diversos patógenos asociados a factores predisponentes del huésped, como la inmunosupresión. A pesar de que se han descripto manifestaciones extraintestinales de salmonelosis, es infrecuente su identificación como agente causal de infecciones de partes blandas; menos común aún es su implicación en la gangrena de Fournier. Nuestro objetivo es describir la presentación, manejo y desenlace de un caso de gangrena de Fournier con cultivos positivos para Salmonella enteritidis.

Fournier's Gangrene is a severe perineal necrotizing fasciitis attributed to the synergistic action of various pathogens associated with host predisposing factors, such as immunosuppression. Although extraintestinal manifestations of salmonellosis have been described, its identification as a causative agent of soft tissue infections is infrequent and its involvement in the Fournier's Gangrene is even less common. Our objective is to describe the presentation, management and outcome of a Fournier's Gangrene case with positive cultures for Salmonella enteritidis.

Carcinoma neuroendocrino rectal: Una neoplasia infrecuente / Neuroendocrine rectal carcinoma: An infrequent tumor

Resumen El carcinoma neuroendocrino (CNE) es una entidad infrecuente encontrándose usualmente al diagnóstico en estadios avanzados. El tratamiento suele ser combinado, quirúrgico junto a quimiorradioterapia. Presentamos el caso de una mujer de 73 años estudiada por síndrome constitucional y rectorragias. Tras completar estudios fue diagnosticada de CNE rectal pobremente diferenciado a 5 cm del margen anal con adenopatías mesorrectales. Inicio quimioterapia de inducción con respuesta parcial y se realizó resección anterior de recto ultrabaja con anastomosis primaria e ileostomia en asa derivativa, con histología de CNE de células grandes pT2N0 Mx. Posteriormente recibió quimioterapia adyuvante. El CNE rectal es una neoplasia rara, presente entre la 4o-7o década de la vida y con sintomatología similar al adenocarcinoma colorrectal, siendo un tumor poco diferenciado y muy agresivo. El papel de la neo adyuvancia es fundamental dado que suele ser una enfermedad avanzada al diagnóstico, disminuye el tamaño del tumor primario y permite realizar posteriormente resecciones oncológicas.

Abstract Neuroendocrine carcinoma (NC) is an infrequent pathology that is usually found in the advanced stages. The treatment is surgery, and combined chemotherapy andradiotherapy. A 73-year old woman was being studied for constitutional syndrome and rectal bleeding. After which, she was diagnosed with a poorly differentiated rectal NC, 5 cm from de anal margin with mesorectal lymph nodes. Induction chemotheraphy was started with partial response. A low anterior resection of rectum was performed with primary anastomoses and diverting loop ileostomy. The histology result was a large-cell NC, staged as pT2N0 Mx. She then received adjuvant chemotherapy. Rectal NC is infrequent, and usually presents between the fourth and seventh decade of life. Its symptoms are similar to colorectal adenocarcinoma, but it has a lower grade of differentiation, and is more aggressive. Neoadjuvant treatment is essential as it usually a metastatic disease at diagnosis, and helps to decrease the tumor size, and allows oncological surgery to be performed later.

Embarazo heterotópico con las nuevas técnicas de reproducción asistida. Reporte de un caso / Heterotopic pregnancy with the new techniques of assisted reproduction. Case report

Resumen Mujer infértil, de 39 años, con diagnóstico de disminución de la reserva ovárica. Tenía 4 intentos previos de fertilización in vitro, sin éxito. Se le realizó fertilización in vitro con donación de óvulos. Fueron transferidos 2 embriones, y la paciente resultó embarazada. Dos semanas después se efectuó un ultrasonido vaginal y se encontró un saco gestacional intrauterino, con embrión y actividad cardiaca. El embarazo evolucionó bien hasta 3 semanas después de la prueba de embarazo, cuando presentó dolor en la fosa iliaca izquierda. Al revisarla se encontró resistencia muscular y rebote en la zona referida. Se efectuó un ultrasonido vaginal y se encontró un feto intrauterino con actividad cardiaca y embarazo ectópico tubario izquierdo. A la paciente se le practicó una laparotomía con incisión Pfannenstiel y se le realizó una salpingectomía izquierda. Después de la cirugía, fue tratada con inhibidores de las contracciones uterinas. El embarazo evolucionó satisfactoriamente hasta la semana 35, cuando presentó ruptura prematura de membranas. Se le realizó una cesárea y se obtuvo un producto masculino que pesó 2,500 g. El recién nacido desarrolló síndrome de dificultad respiratoria leve e hipertensión de la arteria pulmonar, que fueron tratados con agente surfactante y sildenafil; se le egresó en buenas condiciones.

Abstract We present the case of a 39-year-old infertile woman with the diagnosis of diminished ovarian reserve and a history of four previous attempts of in vitro fertilization, which were unsuccessful. She was treated by means of in vitro fertilization with oocyte donation, two embryos being transferred. Two weeks after embryo transfer, the pregnancy test was positive. Two weeks later a vaginal ultrasound was performed, finding an intrauterine gestational sac, within which an embryo with cardiac beat was detected. The pregnancy had a normal evolution until three weeks after the pregnancy test when the patient presented with left-sided lower abdominal pain. On examination, guarding and rebound signs in the left iliac fossa were positive. A vaginal ultrasound was performed, encountering both an intrauterine fetus with cardiac beat and a left tubal ectopic pregnancy. The patient was treated by means of Pfannenstiel incision laparotomy with a left salpingectomy. After surgery, the patient was treated with uterine contractility inhibitors. The pregnancy progressed without complications until the thirty-fifth week, when the patient presented premature rupture of membranes. A cesarean section was performed obtaining a live male, weighing 2500g. The newborn developed mild respiratory distress and pulmonary artery hypertension, for which a surfactant agent and sildenafil were administered. He was deemed healthy and egressed.

Estenosis rectal inflamatoria secundaria a Chlamydia trachomatis: a propósito de un caso / Rectal inflammatory stenosis secondary to Chlamydia trachomatis: a case report

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