Feasibility of Tc-99 m sestamibi uptake quantification with few-projection emission tomography.

BACKGROUND: Molecular breast imaging uses Tc-99 m sestamibi to obtain functional images of the breast. Determining the Tc-99 m sestamibi uptake in volumes of interest in the breast may be useful in assessing the response to neoadjuvant chemotherapy or for the purposes of breast cancer risk assessment. PURPOSE: To determine, using Monte Carlo simulation, if emission tomography can be used to quantify the uptake of Tc-99 m sestamibi in molecular breast imaging and if so, to determine the accuracy as a function of the number of projections used in the reconstruction process. METHODS: In this study, two voxelized breast models are implemented with different ratios of fibroglandular to fatty tissue and tumoral masses of varying dimensions. Monte Carlo simulation is used to calculate sets of projections, which assumes that each tumoral mass contains a given Tc-99 m activity. Projections are also calculated for a calibration phantom in order to correlate the known activity with the image pixel value. For each case, the total number of calculated projections is 36 and the reconstruction is carried out for 36, 18, 9, 7 and 5 projections, respectively, using an open source image reconstruction toolbox. RESULTS: Study data show that determination of Tc-99 m sestamibi uptake with and average error of 7% can be carried out with as little as 7 projections. CONCLUSIONS: Molecular breast emission tomography enables to accurately determine the Tc-99 m sestamibi tumoral mass uptake with the number of projections very close to the number of images currently acquired in clinical practice.

Inequity Analysis in Faculty Recognition Awards at a School of Medicine.

As part of developmental networks, sponsors help provide recognition and visibility opportunities to their faculty protégés. Recognition awards given to the School of Medicine (SOM) faculty are an important mechanism for acknowledging what is valued in academic medicine. Beyond their impact on individual careers, awards help define the culture and climate of an organization. The literature suggests inequities in recognition awards for women and racial/ethnic underrepresented minority faculty. The study's purpose was to examine the characteristics of the awardees relative to the SOM faculty in a minority-serving institution in a minority-majority state. In this observational cross-sectional study, 47 SOM faculty were recognized between 2000-2023 as Regents' Lecturers (9), Regents' Professors (20), Community Engagement Awardees (5), and Gold-headed Cane Awardees (13). SOM sought nominations which a search committee competitively reviewed. Award recipients were characterized by their department, rank, academic track, degree, country of origin, sex, and race/ethnicity, and were compared to all SOM faculty. Male faculty were more likely than women faculty to receive an award (p=0.04). Faculty with tenure, Ph.D. degree, or Professor rank were more likely to receive an award than their counterparts (p<0.001, all analyses). Faculty in basic and diagnostic specialties were more likely to receive an award than medical or surgical specialties (p<0.001). Although rates of awards for racial/ethnic URM faculty were about half that of non-URM faculty, this difference did not reach statistical significance (p=0.14). In addition to demonstrating sex-related inequity in awards, recognized faculty are traditionally associated with the scholarship of discovery compared to other models of scholarship or clinical activity. Sponsors should promote women, physicians, and clinician educators for recognition awards to advance their academic careers. SOM leaders need to examine award criteria and processes to ensure recognition of the diversity of talents and achievements that are critical to the future of academic medicine.

Manejo de pacientes en cirugía oral y maxilofacial durante el periodo de crisis y de control posterior de la pandemia de COVID-19 / Management of patients in oral and maxillofacial surgery during the stage of crisis and subsequent control of COVID-19 pandemic

La pandemia por la nueva infección respiratoria conocida como enfermedad coronavirus 2019 (COVID-19), causada por el virus SARS-CoV-2, ha desencadenado una perturbación sin precedentes en la actividad habitual de los servicios de cirugía oral y maxilofacial en España, retrasando la atención rutinaria de pacientes e intervenciones quirúrgicas programadas. Los cirujanos orales y maxilofaciales son uno de los colectivos sanitarios con mayor riesgo de infección nosocomial por el estrecho contacto que se produce con los pacientes asintomáticos y sintomáticos con infección por SARS-CoV-2 a través de la cavidad oral y orofaringe. El propósito del presente documento ha sido actualizar la evidencia disponible para el manejo y tratamiento seguro y efectivo en consulta, cirugías ambulatorias, programadas y urgentes y hospitalización, minimizando al mismo tiempo, tanto como sea posible, el riesgo de contagio para el cirujano oral y maxilofacial, personal sanitario y pacientes. Este documento pretende esclarecer los aspectos más significativos y crear un protocolo común de manejo de pacientes con COVID-19 en cirugía oral y maxilofacial durante la fase aguda de propagación y de control posterior de la pandemia en nuestro país

The pandemic due to the new respiratory infection known as coronavirus 2019 disease (COVID-19), caused by the SARS-CoV-2 virus, has triggered an unprecedented disruption in the normal activity of oral and maxillofacial surgery departments in Spain, delaying routine patient care and elective surgical interventions. Oral and maxillofacial surgeons are one of the healthcare groups with the highest risk of nosocomial infection because of the close contact that occurs with asymptomatic and symptomatic patients with SARS-CoV-2 infection through the oral cavity and oropharynx. The purpose of this document has been to update the available evidence for the safe and effective management and treatment in outpatient clinic, ambulatory, elective and emergency surgeries, and hospitalization, while minimizing as much as possible the risk of infection for the oral and maxillofacial surgeon, health workers and patients. This document aims to clarify the most significant aspects and create a common protocol for the management of patients with COVID-19 in oral and maxillofacial surgery during the acute stage of spread and subsequent control of the pandemic in our country

A versatile Johansson-type tender x-ray emission spectrometer.

We present a high energy resolution x-ray spectrometer for the tender x-ray regime (1.6-5.0 keV) that was designed and operated at Stanford Synchrotron Radiation Lightsource. The instrument is developed on a Rowland geometry (500 mm of radius) using cylindrically bent Johansson analyzers and a position sensitive detector. By placing the sample inside the Rowland circle, the spectrometer operates in an energy-dispersive mode with a subnatural line-width energy resolution (∼0.32 eV at 2400 eV), even when an extended incident x-ray beam is used across a wide range of diffraction angles (∼30° to 65°). The spectrometer is enclosed in a vacuum chamber, and a sample chamber with independent ambient conditions is introduced to enable a versatile and fast-access sample environment (e.g., solid/gas/liquid samples, in situ cells, and radioactive materials). The design, capabilities, and performance are presented and discussed.

Cartilage oligomeric matrix protein contributes to the development and metastasis of breast cancer.

Cartilage oligomeric matrix protein (COMP) is a soluble pentameric protein expressed in cartilage and involved in collagen organization. Tissue microarrays derived from two cohorts of patients with breast cancer (n=122 and n=498) were immunostained, revealing varying expression of COMP, both in the tumor cells and surrounding stroma. High levels of COMP in tumor cells correlated, independently of other variables, with poor survival and decreased recurrence-free survival. Breast cancer cells, MDA-MB-231, stably expressing COMP were injected into the mammary fat pad of SCID (CB-17/Icr-Prkdcscid/Rj) mice. Tumors expressing COMP were significantly larger and were more prone to metastasize as compared with control, mock-transfected, tumors. In vitro experiments confirmed that COMP-expressing cells had a more invasive phenotype, which could in part be attributed to an upregulation of matrix metalloprotease-9. Furthermore, microarray analyses of gene expression in tumors formed in vivo showed that COMP expression induced higher expression of genes protecting against endoplasmic reticulum stress. This observation was confirmed in vitro as COMP-expressing cells showed better survival as well as a higher rate of protein synthesis when treated with brefeldin A, compared with control cells. Further, COMP-expressing cells appeared to undergo a metabolic switch, that is, a Warburg effect. Thus, in vitro measurement of cell respiration indicated decreased mitochondrial metabolism. In conclusion, COMP is a novel biomarker in breast cancer, which contributes to the severity of the disease by metabolic switching and increasing invasiveness and tumor cell viability, leading to reduced survival in animal models and human patients.

Experimental simulation of decoherence in photonics qudits.

We experimentally perform the simulation of open quantum dynamics in single-qudit systems. Using a spatial light modulator as a dissipative optical device, we implement dissipative-dynamical maps onto qudits encoded in the transverse momentum of spontaneous parametric down-converted photon pairs. We show a well-controlled technique to prepare entangled qudits states as well as to implement dissipative local measurements; the latter realize two specific dynamics: dephasing and amplitude damping. Our work represents a new analogy-dynamical experiment for simulating an open quantum system.

Micosis fungoide con afectación cerebral como primera manifestación extracutánea / Cerebral Involvement as the First Extracutaneous Manifestation of Mycosis Fungoides

No disponible

Experimental characterization of two spatial qutrits using entanglement witnesses.

We present an experimental technique for a complete characterization of entanglement in a two-qutrit state generated using transverse spatial correlations of two parametric down-converted photons. We verify entanglement for a particular case via entanglement witness operators which are decomposed into a sum of local observables of single path and superposition projection operators. Experimentally, these operators are accomplished by using a spatial light modulator and a polarizing beam splitter which allow to modulate the amplitude of individually chosen path states. The quantification of entanglement is computed by the negativity obtained from the expectation values of the entanglement witnesses implemented.

Glycogen synthase kinase 3beta: a novel marker and modulator of inflammatory injury in chronic renal allograft disease.

One key cell-signaling event central to inflammation in kidney diseases, including chronic renal allograft dysfunction or disease (CRAD), is the activation of NF-kappaB, which controls transcription of numerous proinflammatory mediators. Glycogen synthase kinase (GSK) 3beta is an indispensable element of NF-kappaB activation, however, the exact role of GSK3beta in the pathogenesis of inflammatory kidney diseases like CRAD is uncertain and was examined. Immunohistochemistry staining of GSK3beta was weak in normal kidneys, but was markedly induced in inflamed allograft kidneys, with prominent cytoplasmic staining of tubular cells in areas of inflammation. Net GSK3beta activity is regulated by inhibitory phosphorylation of its serine 9 residue, and this occurred in CRAD. Thus, the magnitude of GSK3beta inactivation was inversely correlated with the degree of injury as assessed by Banff criteria. In vitro in cultured human tubular epithelial cells, GSK3beta overexpression augmented, while GSK3beta silencing diminished proinflammatory cellular responses to TNF-alpha stimulation, including NF-kappaB activation and expression of chemokines MCP-1 and RANTES. These inflammatory responses were obliterated by GSK3beta inhibitors. Collectively, GSK3beta plays an important role in mediating proinflammatory NF-kappaB activation and renal inflammation. Suppression of GSK3beta activity might represent a novel therapeutic strategy to treat CRAD.

An economic model of haemophilia in Mexico.

A model was developed to assess the lifetime costs and outcomes associated with haemophilia in Mexico. A retrospective chart review of 182 type A haemophiliacs was conducted for patients aged 0-34 years receiving one of three treatments: (i) cryoprecipitate at clinic; (ii) concentrate at home; or (iii) concentrate at clinic. Patients treated at home experienced 30% less joint damage, used 13-54% less factor VIII, had four times fewer clinic visits, and utilized half as many hospital days than those treated at a clinic. For cryoprecipitate at clinic patients, the annual incidence rates of HCV and HIV were calculated to be 3.6% and 1.4% respectively. The life expectancy for patients receiving cryoprecipitate and those receiving concentrate was estimated to be 49 years and 69 years respectively, with 58% of cryoprecipitate patients predicted to die of AIDS before age 69. Across the lifespan, the average annual cost of care was US$11,677 (MN$110,464) for cryoprecipitate at clinic patients, US$10,104 (M$95,580) for concentrate at home patients and US$18,819 (MN$178,027) for concentrate at clinic patients. Using a 5% discount rate, the incremental lifetime cost per year of life added for treatment with concentrate at home compared with cryoprecipitate at a clinic was US$738 (MN$6981). Rank order stability analysis demonstrated that the model was most sensitive to the cost of fVIII. These results indicate that treatment with concentrate at home compared with cryoprecipitate at a clinic substantially improves clinical outcomes at reduced annual cost levels.

Preparation and thermoluminescence properties of aluminium oxide doped with europium.

There is little information concerning the use of rare earths as dopants of Al2O3. This paper presents the preparation method and the results of studying the thermoluminescence characteristics of Al2O3:Eu exposed to ultraviolet light. Phosphor powder was obtained by the evaporation method. Optimum dopant concentration was 10% at an evaporation temperature of 700 degrees C. The powder obtained was submitted to thermal treatments at high temperatures in order to stabilise the traps. Diffraction patterns showed amorphous powder up to 500 degrees C; as the temperature was raised crystalline phases of Al2O3 appeared. The photoluminescence spectrum induced by 250 nm UV light exhibited four well defined peaks characteristic of the Eu3+ ion. The glow curve exhibited two peaks at 180 and 350 degrees C. The sensitivity of Al2O3:Eu was 10 times lower than Al2O3:C. The thermoluminescence response was linear from 2.4 to 3000 microJ.cm(-2) of spectral irradiance, and the fading 2% in a month. From these results it can be concluded that Al2O3:Eu has potential as an UV dosemeter.

[Periodical EEG pattern modifications in herpetic encephalitis treated with acyclovir]. / Modificaciones del patrón EEG periódico en las encefalitis herpéticas tratadas con aciclovir.

The presence of PLED or localized or lateralized periodic activity in encephalitis strongly suggests that the encephalitis is due to the herpes simplex virus. Nevertheless, there has been controversy over its clinical significance. In addition, since the introduction of antiviral drugs in the treatment of herpes encephalitis in its initial stages, the prognosis of the disease has improved. We studied nine patients all diagnosed as having herpes encephalitis and treated with acyclovir. The presence or absence of periodic activity and its characteristics were analyzed. It was seen that either there was no such activity, or if there was, it was not exactly as classically described.

Proliferative glomerulonephritis with unusual, organized, cylindrical deposits associated with angioimmunoblastic lymphadenopathy-like T-cell lymphoma.

We describe an elderly man who developed angioimmunoblastic lymphadenopathy-like T-cell lymphoma, followed by acute renal failure 2 months later. Renal biopsy revealed proliferative glomerulonephritis, which was characterized by enlarged glomeruli with increased cellularity, thickened capillaries, intracapillary inflammatory cells, focal necrosis, and fibrin extravasation. Immunofluorescence studies revealed capillary and mesangial deposits of IgG, IgM, IgA, Ig kappa, Ig lambda, and C3. Electron microscopy revealed unusual, organized, electron-dense deposits in the capillary walls and mesangium. The deposits occurred as accumulations of large rigid tubules or cylinders, which, in longitudinal section, were double-walled. In transverse section, the deposits were annular or horseshoe shaped and occasionally had a central filament. The morphologic characteristics of these deposits are different from those seen in cryoglobulinemia or fibrillary and immunotactoid glomerulopathies. The significance of these deposits is uncertain; they may represent a cryoglobulin or an abnormal serum protein related to angioimmunoblastic lymphadenopathy-like T-cell lymphoma. The findings in this case expand the morphologic spectrum of glomerular lesions that may be associated with malignant lymphoproliferative disorders and, particularly, angioimmunoblastic lymphadenopathy-like T-cell lymphoma.

Molecular heterogeneity of G-6-PD deficiency in Mexico.

DNA samples from seven G-6-PD deficient Mexican mestizo patients were analyzed. Three different G-6-PD genotypes were observed: G-6-PD A-202A/376G (three patients), G-6-PD A-376G/968C (three patients) and G-6-PD Seattle844C. The present results, along with previous reports, suggest not only G-6-PD A-genotypes are relatively common but also G-6-PD deficiency seems to be heterogeneous at DNA level in Mexico.

Systemic mast cell disease presenting with peripheral blood eosinophilia.

Patients with mast cell disease most frequently present with skin lesions (urticaria pigmentosa), with systemic involvement in many cases. However, a small subset of patients with systemic mast cell disease lacks skin lesions and, in these patients the correct diagnosis may be difficult to establish. Patients with systemic mast cell disease commonly have hematologic abnormalities, including eosinophilia in up to 20% of cases, but isolated eosinophilia has been reported rarely. We describe an 82-year-old woman who was admitted to Rhode Island Hospital for coronary artery disease and unstable angina. Incidentally, an absolute eosinophil count of 7.84 x 10(9)/L (normal, < 0.45 x 10(9)/L) was detected with moderate thrombocytopenia and mild anemia. Review of earlier records revealed that absolute eosinophilia had been present for approximately 4 months, initially without other hematologic abnormalities. Clinical work-up showed left upper quadrant tenderness. No skin lesions were identified. Bone marrow core biopsy revealed paratrabecular, perivascular, and medullary mast cell aggregates with eosinophils, suggestive of mast cell disease. At autopsy the diagnosis was confirmed. Mast cell aggregates were found in the liver, spleen, lymph nodes, and bone marrow, and chloroacetate esterase stain highlighted mast cell granules. The bone marrow was also hypercellular with granulocytic and eosinophilic hyperplasia, suggestive of a poorly defined myeloproliferative disorder. Patients with systemic mast cell disease initially may present with peripheral eosinophilia. Clinical suspicion of the diagnosis facilitates proper handling of the bone marrow core biopsy specimen to allow the demonstration of mast cell granules.

Hipertrofia prostatica benigna y cirugia abierta / HBP and open surgery

Se plantea la cirugía abierta como una alternativa en el tratamiento de la Hipertrofia prostática con el objetivo de resolver los problemas de la obstrucción urinaria clínica anatómica y funcionalmente. Conociendo algunas de las indicaciones se enumeran tres modalidades de cirugía abierta, se resaltan aspectos según la patología concomitante para escoger la técnica más efectiva y el menor número de complicaciones y los resultados logren el objetivo planteado

Fine needle aspiration cytology of primary squamous cell carcinoma of the thymus. A case report.

We present the cytologic findings of a rare case of primary thymic squamous cell carcinoma with ultrastructural examination and histologic confirmation of the tumor. The clinicopathologic features of thymic carcinomas are discussed. Although the cytodiagnosis of squamous cell carcinomas in general is not difficult, we have observed some cytologic (and histologic) features that we think are distinctive in thymic squamous carcinoma.