Atresia de coana bilateral en adulto con malformación craneofacial asociada: un diagnóstico poco habitual / Bilateral choanal atresia in adult with associated craneofacial malformation: an unusual diagnosis

La atresia de coana es una rara malformación congénita improbable de encontrar de forma bilateral en un adolescente o adulto. Hasta la fecha, no se ha descrito ningún caso de atresia bilateral en un adulto con una malformación asociada de cabeza y cuello que haya requerido tratamiento conjunto. El tratamiento de elección de la atresia de coana bilateral continúa siendo la cirugía endoscópica, con controversia en el uso intraoperatorio de mitomicina o la colocación de stents para evitar estenosis. Lo que no está claro es el orden de tratamiento y la simultaneidad del procedimiento si se asocian otras posibles patologías que tengan una indicación quirúrgica. Presentamos un caso clínico que cumple con todos estos requisitos.

Choanal atresia is a rare congenital malformation that is unlikely to be found bilaterally and is seldom diagnosed in adulthood. To date, no clinical case of bilateral atresia has been described with a head and neck malformation that requires surgical treatment in an adult. The preferred treatment is still endoscopic sinonasal surgery with discrepancies of the use or not of intraoperative topical mitomycin or the placement of stents to avoid restenosis. What is not clear is the order of treatment and simultaneity of the procedure with other possible associated pathologies that have a surgical indication. We present a clinical case that meets all these requirements.

Patologías benignas y variantes que captan 68Ga-DOTATATE en PET/TC / Benign Pathology And Variants With Uptake In 68ga-Dotatate Pet/Ct Studies

Objetivos: Valorar las variantes fisiológicas, anatómicas y lesiones benignas en estudios por tomografía computada por emisión de positrones (PET/TC) con Galio 68 (68Ga)-DOTATATE. Materiales y métodos: Se revisaron en forma retrospectiva los informes de PET/TC con 68Ga-DOTATATE y se seleccionaron aquellos en los cuales se mencionaran palabras en el reporte relacionadas a variantes anatómicas, fisiológicas y tumores benignos. El grado de captación del 68Ga-DOTATATE fue evaluado de forma cualitativa y cuantitativa mediante la medición del valor estandarizado de captación máximo (SUVmax). Se consignó la localización del hallazgo, el valor de SUVmax y la imagen morfológica por tomografía computada (TC). Todos los casos fueron controlados mediante evolución clínica y hallazgos imagenológicos. Resultados: De un total de 772 informes de PET/TC se obtuvo un total de 28 pacientes con 33 variantes o tumores benignos, 14 mujeres y 14 hombres con edad promedio de 63 años. Las captaciones se clasificaron en cuatro grupos: variantes anatómicas y/o fisiológicas (n = 15), dependientes de la actividad osteoblástica (n=4), dependientes de actividad inflamatoria (n = 10) y tumores benignos no neuro-endócrinos (n = 4). Discusión: Los receptores de somatostatina se localizan no sólo en el sistema neuroendócrino sino también en otros tejidos. Las variantes fisiológicas, anatómicas y tumores benignos que expresan estos receptores pueden inducir a un error diagnóstico. Conclusión: Las variantes fisiológicas y lesiones benignas (tumorales e inflamatorias) pueden captar 68Ga-DOTATATE ya que sus tejidos pueden expresar receptores de somatostatina. El análisis semiológico del componente tomográfico de este método de imágenes híbrido, permite la orientación diagnóstica, optimizando el rendimiento del estudio PET/TC.

Purpose: To evaluate the physiological, anatomical variants and benign lesions in positrón emission computed tomography (PET/CT) studies with 68Ga-DOTATATE. Materials and methods: We retrospectively reviewed PET/CT reports scanned with 68Ga-DOTATATE and selected those that contained words in the report related to anatomical, physiological variants and benign tumors. The degree of 68Ga-DOTATATE uptake was evaluated qualitatively and quantitatively by measuring the standarized uptake max value (SUVmax value). The anatomical location, SUVmax value and morphological CT image findings were recorded. All cases had clinical and imaging follow-up. Results: From a total of 772 PET/CT reports, 28 patients were obtained with 33 benign variants or tumors, 14 females and 14 males with a median age of 63 years. Uptake patterns were classified into four groups: anatomic and physiological variants (15), dependent on osteoblastic activity (4), dependent on inflammatory activity (10) and non-neuro-endocrine benign tumors (4). Discussion: Somatostatin receptors are overexpressed not only in the neuroendocrine system but also in other tissues. Physiological, anatomical variants and benign tumors expressing these receptors may be misleading. In the present work the frequency of this finding is 5.1%. Conclusion: Physiological variants and benign lesions (tumor and inflammatory) can accumulate 68Ga-DOTATATE since their tissues can express somatostatin receptors. The semiologic analysis of the tomographic component of this hybrid method enhances the diagnostic efficacy, optimizing PET/CT study performance.

[Early diagnosis of hip dysplasia. Crippling disease for life. Consensus of the Mexican College of Orthopedics and Traumatology]. / El diagnóstico oportuno de la displasia de cadera. Enfermedad discapacitante de por vida. Consenso del Colegio Mexicano de Ortopedia y Traumatología.

The developmental dysplasia of the hip (DDH), where the spectrum of deformity varies from a slight mismatch in the articular surfaces between the ilium and femur, which will bring a premature wear of the joint, until the situation more serious when the femoral head is out of the acetabulum, causing a host of disorders side as curvature of the spine, significant shortening of the limb deformities in the knee and the contralateral hip, as well as causing pain and loss of joint mobility mentioned. All this makes the spectrum of abnormalities in a person being disabled with a social and economic burden for the family and society. "Preventing" a clinical entity such as developmental dysplasia of the hip does not mean to anticipate the presentation, because children continue to be born with this problem, but to have a program for early detection and early treatment and thus prevent the occurrence. The goal of this study was to provide the medical community that timely tool for prevention. When diagnosed and treated in a timely and favorable prognosis qualified for motor function and quality of life.

A clinical gamma camera-based pinhole collimated system for high resolution small animal SPECT imaging

The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target’s three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology.

A clinical gamma camera-based pinhole collimated system for high resolution small animal SPECT imaging.

The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target's three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology.

A combined study of behavior and Fos expression in limbic structures after re-testing Wistar rats in the elevated plus-maze.

The elevated plus-maze is an animal model used to study anxiety. In a second session, rats show a reduction in the exploratory behavior even when the two sessions are separated by intervals as large as 7 days. The aim of the present study was to investigate whether the reduction in the exploratory behavior is maintained after intervals larger than 7 days. Additionally, we aimed at investigating eventual correlations between behaviors in the plus-maze and activation of limbic structures as measured by Fos protein expression after the second session. Rats were tested for 5 min in the elevated plus-maze and re-tested 3, 9 or 33 days later. Other groups were tested only once. The rat brains were processed for immunohistochemical detection of Fos protein. The results show a decrease in the open arms exploration in the second trial with intervals of 3, 9 and 33 days. The expression of Fos protein in the piriform cortex, septal nucleus and paraventricular hypothalamic nucleus in the groups tested with intervals of 9 and 33 days were statistically different from the other groups. The alterations observed in exploratory behavior in the second session in the plus-maze did not correlate with Fos expression. In conclusion, although the specific test conditions were sufficient to evoke behavioral alterations in exploration in the elevated plus-maze, they were enough to induce significant Fos protein expression in piriform cortex, septal nucleus and thalamic and hypothalamic paraventricular nuclei but not in other areas such as dorsomedial nucleus of the hypothalamus and amygdala nuclei, known to be also active participants in circuits controlling fear and anxiety.

Methodological approaches to planar and volumetric scintigraphic imaging of small volume targets with high spatial resolution and sensitivity.

Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial resolution and sensitivity. Multipinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target's radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals.

Methodological approaches to planar and volumetric scintigraphic imaging of small volume targets with high spatial resolution and sensitivity

Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial resolution and sensitivity. Multipinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target’s radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals.

Deformidad podálica: presentación de un caso / Podalic deformity: a case report

Se presenta una paciente de 51 años de edad y blanca que fue operada de Hallux Valgus del pie izquierdo con la técnica de McBride modificada y que evolutivamente se le diagnosticó un Sudeck y presentó una severa deformidad en garras de los dedos que le dificultaba la marcha. El objetivo fue lograr un pie plantígrado con la técnica quirúrgica de plastias tendinosas de los extensores y flexores de los dedos del pie y las artrodesis metatarsofalángicas. A través de un abordaje dorsal del pie se pudo realizar las plastias tendinosas y las artrodesis de las cinco articulaciones metatarsofalángicas. Su evolución fue satisfactoria y a las 12 semanas ya la paciente podia caminar y calzar zapatos cómodos, a las 20 semanas se le dio el alta definitiva.

It is presented a white female, 51-years-old patient that was operated on, by suffering from Hallux Valgus in the left foot, by means of McBride modified technique being later diagnosed a Sudeck and presented a severe deformity in claws of the fingers that complicated her to walk. The objective of this work was to achieve a plantigrade foot by putting into practice the tendinous plasties surgical technique of the extensors and flexores of the toes and the metatarsophalangeal arthrodesis. Through a dorsal approach of the foot could be carried out the tendinous plasties and the arthrodesis of the five metatarsophalangeal joints. Her evolution was satisfactory; 12 weeks later the patient could already walk and wear comfortable shoes and after 20 weeks she was finally discharged.

Muscarinic acetylcholine neurotransmission enhances the late-phase of long-term potentiation in the hippocampal-prefrontal cortex pathway of rats in vivo: a possible involvement of monoaminergic systems.

The prefrontal cortex is continuously required for working memory processing during wakefulness, but is particularly hypoactivated during sleep and in psychiatric disorders such as schizophrenia. Ammon's horn CA1 hippocampus subfield (CA1) afferents provide a functional modulatory path that is subjected to synaptic plasticity and a prominent monoaminergic influence. However, little is known about the muscarinic cholinergic effects on prefrontal synapses. Here, we investigated the effects of the muscarinic agonist, pilocarpine (PILO), on the induction and maintenance of CA1-medial prefrontal cortex (mPFC) long-term potentiation (LTP) as well as on brain monoamine levels. Field evoked responses were recorded in urethane-anesthetized rats during baseline (50 min) and after LTP (130 min), and compared with controls. LTP was induced 20 min after PILO administration (15 mg/kg, i.p.) or vehicle (NaCl 0.15 M, i.p.). In a separate group of animals, the hippocampus and mPFC were microdissected 20 min after PILO injection and used to quantify monoamine levels. Our results show that PILO potentiates the late-phase of mPFC LTP without affecting either post-tetanic potentiation or early LTP (20 min). This effect was correlated with a significant decrease in relative delta (1-4 Hz) power and an increase in sigma (10-15 Hz) and gamma (25-40 Hz) powers in CA1. Monoamine levels were specifically altered in the mPFC. We observed a decrease in dopamine, 5-HT, 5-hydroxyindolacetic acid and noradrenaline levels, with no changes in 3,4-hydroxyphenylacetic acid levels. Our data, therefore, suggest that muscarinic activation exerts a boosting effect on mPFC synaptic plasticity and possibly on mPFC-dependent memories, associated to monoaminergic changes.

Fracturas de cadera: 1995-2005 / Hip fractures: 1995-2005

Se realizó un estudio descriptivo y retrospectivo de 681 pacientes ingresados en el Servicio de Ortopedia y Traumatología del Hospital General Docente Roberto Rodríguez Fernández de Morón en el período comprendido entre enero de 1995 a diciembre del 2005, con el diagnóstico de Fractura de Cadera. El objetivo general fue determinar las posibles causas del síndrome y los objetivos específicos fueron determinar las distintas variables sociodemográficas (edad, sexo, raza, municipio, antecedentes patológicos personales), clasificación de la fractura, implante empleado, complicaciones. Del universo de estudio el 84,6 por ciento pertenecía a la raza blanca y el 68.4 por ciento al sexo femenino. La incidencia fue mayor en el grupo de edades de 71-80 años para un 30 por ciento. La caída de los pies fue la causa de la fractura en el 95 por ciento de los casos. Las fracturas extracapsulares fueron las más frecuentes (68,3 por ciento). El municipiop con mayor incidencia fue Morón (32,74 por ciento). Los implantes más frecuentemente empleados fueron los clavos placa AO de 130º en 320 pacientes (47 por ciento) seguidos por la artroplastia parcial en 154 casos (22,6 por ciento). La hipertensión arterial en 169 pacientes (24,8 por ciento) y la cardiopatía isquémica en 151 casos (22,1 por ciento) fueron los antecedentes patológicos más frecuentemente encontrados. 22,02 por ciento de los pacientes ingresados por fractura presentaron algún tipo de complicación poistquirúrgica; siendo la bronconeumonía en 102 pacientes (68 por ciento) la complicación más frecuente.

A descriptive and retrospective study of 681 hospitalized patients in the Orthopaedic and Traumatology Service at Roberto Rodríguez Fernández General Teaching Hospital of Morón was carried out from January 1995 to December 2005, with a diagnosis of hip fracture. The general objective was to determine the possible causes of the syndrome and the specific objectives were to determine the different sociodemographic variables (age, sex, race, municipality, personal pathological records), classification of the fracture , implant used and complications. From the universe of study, 89,6 percent of the patients were white and 68,4 percent female. The incidence was higher in the group aged 71-80 years for a 30 percent. Falling was the cause of fracture in 95 percent of the cases. Extra-capsular fractures were the most frequuent (68,3 percent). Morón was the mucinipality with more incidence (32,74 percent). The most frequent implants used were the plate nails AO of 130o in 320 patients (47 percent) followed by partial arthroplasty in 154 cases (22,6 percent). Highblood pressure in 169 patients (24,6 percent) and ischemic heart disease in 151 cases (22,1 percent) were the pathological records more frequently found. 22,02 percent of the patients hospitalized due to fractures presented some kind of postsurgical complication: bronchopneumonia was the most frequent in 102 patients (68 percent).

[Value of radioguided surgery with dobutamine 99mTc-MIBI in persistent secondary hyperparathyroidism]. / Valor de la cirugía radioguiada con 99mTc-MIBI sensibilizada con dobutamina en el hiperparatiroidismo secundario persistente.

99mTc-MIBI is a radiopharmaceutical that has been successfully used for the detection of hyperfunctioning parathyroid glands and for radioguided surgery techniques. We report on the case of a 55 year old woman in hemodialysis, with secondary persistent hyperparathyroidism after total parathyroidectomy. The conventional double-phase 99mTc-MIBI parathyroid scintigraphy was negative. The study was repeated after sensibilization with intravenous low-dose dobutamine showing an area of increased focal uptake in the lower cervical region. With this finding, radioguided 99mTc-MIBI surgery was performed after dobutamine administration, using a hand held gamma probe. The technique was considered successful with the resection of parathyroid cervical tissue which was further confirmed as nodular hyperplasia. We conclude that this methodology has the potential of being a an useful tool for the intraoperative localization of remanent tissue in patients with secondary persistent/recurrent hyperparathyroidism.

Relación entre la expresión de Glicoproteína P y los hallazgos de la centellografía con Tc-99m MIBI en pacientes con cáncer mamario avanzado / Relation between P-glycoprotein expression and scintigraphic findings with Tc-99m MIBI in advanced breast cancer patients

En un estudio previo encontramos que el grado de captación tumoral pre-tratamiento de Tc-99m MIBI, un sustrato de transporte de la Glicoproteína P (Pgp), se correlaciona con la respuesta clínica a la quimioterapia basada en antraciclinas en pacientes con cáncer mamario avanzado (CMA). El objetivo del presente estudio fue determinar la relación entre la expresión tumoral de Pgp, el grado de captación tumoral de MIBI y la respuesta clínica a la quimioterapia en pacientes con CMA. Se estudiaron 27 lesiones correspondientes a 26 pacientes. La expresión de Pgp fue investigada previamente a la quimioterapia mediante inmunocitoquímica. Las imágenes centellográficas fueron realizadas dentro de la semana previa a la quimioterapia, 10 minutos (fase temprana) y 60 minutos (fase tardía) después de la inyección de 740-1110 MBq de Tc-99m MIBI. La captación lesional fue cuantificada mediante tasa de conteo tumor/fondo en las fases precoz (T/Fp) y tardía (T/Ft) del estudio. Ambos índices fueron superiores (p< 0.05) en las lesiones Pgp negativas (n=21) que en las Pgp positivas (n=6). Además, fueron más elevados en las lesiones respondedoras que en las no respondedoras (T/Fp 2.2 vs 1.4; T/Ft 1.8 vs 1.4; p< 0.05). Todas las lesiones con un índice T/Fp mayor de 1.5 respondieron a la quimioterapia. No se encontró asociación significativa entre la expresión de Pgp y la respuesta a la quimioterapia. Concluimos que la centellografía con MIBI puede predecir el fenotipo MDR1 y la respuesta a la quimioterapia basada en adriamicina en pacientes con CMA. El nivel de expresión de Pgp no sería útil para predecir dicha respuesta.

Limbic epileptogenicity, cell loss and axonal reorganization induced by audiogenic and amygdala kindling in wistar audiogenic rats (WAR strain).

Audiogenic seizures are a model of generalized tonic-clonic brainstem-generated seizures. Repeated induction of audiogenic seizures, in audiogenic kindling (AuK) protocols, generates limbic epileptogenic activity. The present work evaluated associations between permanence of AuK-induced limbic epileptogenicity and changes in cell number/gluzinergic terminal reorganization in limbic structures in Wistar audiogenic rats (WARs). Additionally, we evaluated histological changes after only amygdala kindling (AmK) and only AuK, and longevity of permanence of AuK-induced limbic epileptogenicity, up to 160 days. WARs and Wistar non-susceptible rats were submitted to AuK (80 stimuli) followed by both 50 days without acoustic stimulation and AmK (16 stimuli), only AmK and only AuK. Cell counting and gluzinergic terminal reorganization were assessed, respectively, by using Nissl and neo-Timm histochemistries, 24 h after the last AmK stimulus. Evaluation of behavioral response to a single acoustic stimulus after AuK and up to 160 days without acoustic stimulation was done in another group. AuK-induced limbic epileptogenicity developed in parallel with a decrease in brainstem-type seizure severity during AuK. AmK was facilitated after AuK. Permanence of AuK-induced limbic epileptogenicity was associated with cell loss only in the rostral lateral nucleus of amygdala. Roughly 20 generalized limbic seizures induced by AuK were neither associated with hippocampal cell loss nor mossy fiber sprouting (MFS). AmK developed with cell loss in hippocampal and amygdala nuclei but not MFS. Main changes of gluzinergic terminals after kindling protocols were observed in amygdala, perirhinal and piriform cortices. AuK and AuK-AmK induced a similar number and type of seizures, higher than in AmK. AmK and AuK-AmK were associated with broader cell loss than AuK. Data indicate that permanent AuK-induced limbic epileptogenicity is mainly associated to gluzinergic terminal reorganization in amygdala but not in the hippocampus and with no hippocampal cell loss. Few AmK-induced seizures are associated to broader and higher cell loss than a higher number of AuK-induced seizures.

Predictive value of (99m)Tc sestamibi scintigraphy in the evaluation of doxorubicin based chemotherapy response in patients with advanced breast cancer.

Resistance to doxorubicin based chemotherapy is a major therapeutic problem limiting advanced breast cancer treatment. 99mTc hexakis-2-methoxyisobutylisonitrile ((99m)Tc-MIBI) has been reported to be extruded from tumour cells by the P-glycoprotein and multidrug resistance protein encoded by MDR1 and MRP1 genes, respectively. These proteins are involved in the cellular efflux of several chemotherapeutic agents including doxorubicin. The aim of this study was to investigate the clinical value of a standard (99m)Tc-MIBI scintimammography technique in the prediction of response to chemotherapy in advanced breast cancer patients. Fifty-six lesions from 33 female patients with locally advanced (n=27) or recurrent breast cancer (n=6) were included in the study. MIBI scintigraphy was performed 2-8 days prior to chemotherapy (FAC regimen). Images were acquired 10 min and 1 h post-injection of 740-1110 MBq of (99m)Tc-MIBI. Tumour-to-normal background tissue uptake ratios were calculated on each lesion in the early (T/B(e)) and delayed phase of the study (T/B(d)). Both T/B(e) and T/B(d) ratios were significantly higher (P<0.0001) in responders (n=43) than nonresponders (n=13). Diagnostic values of (99m)Tc-MIBI in the prediction of chemotherapy response were evaluated using the arbitrary cut-off values of 1.5 for T/B(e) and 1.4 forT/B(d). Sensitivity, specificity, positive and negative predictive values were 88.4%, 92.3%, 97.4%, 70.6%; and 90.7%, 100.0%, 100.0%, 76.6%, for T/B(e) and T/B(d), respectively. We conclude that (99m)Tc-MIBI scintigraphy may be a clinically valuable tool for guiding chemotherapy in advanced breast cancer patients.

Is (99m)Tc-sestamibi scintimammography complementary to conventional mammography for detecting breast cancer in patients with palpable masses?

UNLABELLED: The aim of this trial was to evaluate in developing countries from different regions the diagnostic performance of (99m)Tc-sestamibi scintimammography (SM) in palpable breast lesions and to verify the clinical usefulness of a joint evaluation with mammography and SM. METHODS: From 10 countries, a total of 238 patients with palpable breast masses (n = 245) were included in this prospective multicenter trial. Prone SM was performed 10 min and 60-90 min (157 patients) after injection using an isotime acquisition of 10 min. Mammography was assessed by the same dedicated imaging radiologist according to breast imaging reporting and data system (BI-RADS) categories for malignancy and breast density. Masked SM findings and mammography findings were checked for a correlation with histopathology findings for excisional biopsy samples. Diagnostic values for breast cancer detection were calculated per lesion. RESULTS: Histopathology revealed 189 cancerous lesions and 56 benign lesions. The sensitivity and specificity of SM were 0.83 and 0.77, respectively. SM diagnostic values did not depend on the incidence of breast cancer in the country of origin or on the timing of imaging (early vs. delayed scans). On mammography, the technique yielded a sensitivity and specificity of 0.85 and 0.66, with 27 mammograms classified as BI-RADS category 1, 33 as category 2, 5 as category 3, 56 as category 4, and 124 as category 5. Thirty-seven lesions were considered to show increased radiologic density. No significant difference was found in SM diagnostic values among different BI-RADS categories or between the groups with low and high breast density. A sensitivity of 96% was calculated when SM and mammography results were combined, with 75% of all false-negative mammography findings classified as true-positive results by SM. CONCLUSION: SM complements mammography in patients with palpable masses and negative mammography findings.

Audiogenic kindling in the Wistar rat: a potential model for recruitment of limbic structures.

Repetitive high intensity (110 dB) sound stimulation induces a forebrain-kindling phenomenon in animals predisposed to sound induced seizures. Wistar audiogenic rats (WARs) have been reported to develop a mixed brainstem-limbic seizure pattern, after more than five to ten stimuli. Besides the original brainstem wild running and tonic-clonic seizures, new behavioral patterns appear resembling those of electrical amygdala kindling. Although audiogenic kindling is a well-known phenomenon, electrographic limbic recruitment during the kindling has never been reported. Our objective was to use electrophysiology to test the hypothesis of gradual and sequential involvement of the amygdala and then cortex during audiogenic kindling. We used video-EEG recordings with cortical and deep electrode implants (inferior colliculus and basolateral amygdaloid nuclei) during audiogenic kindling on eight WARs, and their respective controls, submitted to a protocol of three acoustic stimuli per day. A new design for 'on site' source follower circuits was used in order to minimize noise during the recording of EEG data from the wild running episode and the subsequent tonic-clonic or motor limbic seizures. The video-EEG equipment assembled allowed synchronous recordings of both behavior and EEG. WARs first recordings showed electrodecremental responses after seizure onset and a probable epileptiform activity, particularly in the inferior colliculus, during the tonic phase of seizure. All animals showed very similar polyspike-wave activity in the amygdala, after behavioral seizure patterns (Racine's scale) occurred. The morphology of such epileptiform EEG activity is very similar to that reported for electrical amygdala kindling. Also, when audiogenic kindling continued, both inferior colliculus and cortical electrodes presented high amplitude and synchronized epileptiform polyspike activity.

Synthesis of terminal disaccharide elements corresponding to the Ogawa and Inaba antigenic determinant from Vibrio cholerae O1.

Vibrio cholerae O1 LPS terminal mono- and disaccharide elements were synthesized by reduction of the azido group in several 4-amino-4,6-dideoxy-D-mannose mono- and disaccharide derivatives, followed by coupling with 2, 4-di-O-acetyl-3-deoxy-L-glycero-tetronic acid in the presence of 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline. This compound represents a useful model in order to elucidate the size of the epitopes which define Ogawa and Inaba serotypes from Vibrio cholerae O1.