Malaria quantitative POC testing using magnetic particles, a paper microfluidic device and a hand-held fluorescence reader.

A point-of-care (POC) device is reported for highly sensitive and selective detection of Plasmodium falciparum lactate dehydrogenase (Pf-LDH), a biomarker of malaria infection, based on a single-step magneto-immunoassay, a single-use microfluidic paper device and a customized hand-held fluorescence reader. The single-step magneto-immunoassay consists in a single 5-min incubation of immuno-modified magnetic particles (c-MAb-MPs), biotinylated detection antibody (bd-MAb), and an enzymatic signal amplifier (Poly-HRP). After on-chip MP concentration and washing, signal generation is achieved by adding a fluorescent enzymatic substrate (QuantaRed). Fluorescence signal is measured using a low-cost customized, portable, and sensible fluorescent detector. The POC affords quantitative Pf-LDH detection in <20 min, with a detection limit of 0.92 ng mL-1 (equivalent to 4.6 parasites µL-1). Furthermore, Pf-LDH quantitation in clinical samples correlates with that provided by the reference ELISA, is more sensitive than a commercial rapid diagnostic test (RDT) and entails little user intervention. These results show that fluorescent paper-based microfluidic devices can be exploited to simplify magneto-immunoassay handling, taking this type of test closer to the requirements of POC testing.

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.

An internet of things-based intensity and time-resolved fluorescence reader for point-of-care testing.

A miniature internet of things (IoT)-based point-of-care testing (PoCT) fluorescence reader, able to perform both intensity and time-resolved measurements of different fluorescent tags, is presented. This low cost platform has been conceived for performing tests in low-resource and remote settings, displaying versatile performance and yet simple operation. It consists on an external case of 43 × 30 × 42 mm3 (built in a 3D-printer) where all the elements are fixed, including some basic optics (3 lenses and 2 filters), a laser diode and a custom designed Single-Photon Avalanche Diodes (SPADs) camera. Both, the laser and the camera are controlled by a Field Programmable Gate Array (FPGA) with IoT capabilities. The PoCT was validated by detecting Plasmodium antigen in a fluorescent enzyme-linked immunosorbent assay (ELISA) using a fluorescence substrate. The results were compared to those provided in parallel by two commercial fluorescent plate readers. As it will be shown, the PoCT fluorescent readout was more sensitive than its colorimetric counterpart. Furthermore, the PoCT displayed similar signal trends and levels of detection than the bulkier and more expensive commercial fluorescence plate readers. These results demonstrate that the PoCT platform developed could bring the performance of central laboratory assay techniques closer to the end-user level.

Intraindividual comparison of 68Ga-DOTATATE PET / CT vs 11C-Choline PET / CT in patients with prostate cancer in biochemical relapse: in vivo evaluation of the expression of somatostatin receptors. / Comparación intraindividual de la PET/TC con 68Ga-DOTATATE vs. PET/TC con 11C-colina en pacientes con cáncer de próstata en recaída bioquímica: evaluación in vivo de la expresión de receptores de la somatostatina.

BACKGROUND AND OBJECTIVES: To prospectively compare the detection rate of 68Ga-DOTATATE versus 11C-choline PET/CT in patients with prostate cancer in biochemical relapse, and to evaluate somatostatin receptor expression in vivo to plan targeted therapies (177Lu-DOTATATE). MATERIAL AND METHODS: We prospectively analysed 64 patients with biochemical relapse (median PSA: 4.25 ng/mL). A PET/CT was performed with 11C-choline, and another with 68Ga-DOTATATE. The SUVmax was measured in all lesions. The correlative images, histopathology and/or clinical and biochemical follow-up were taken as the reference standard. RESULTS: The overall detection rate per patient was 48.43% for 68Ga-DOTATATE and 46.87% for 11C-choline. The results were concordant in 53 cases (82.81%). The maximum SUV of 11C-choline was significantly higher than that of 68Ga-DOTATATE for all the concordant lesions (n=130): 6.17 (1.7-15.5) versus 4.38 (1.37-26.7), median (range) for each radiotracer, respectively (p < .0001). The sensitivity and specificity values per patient were the same for both techniques: 0.82 (0.65-0.93) and 0.9 (0.73-0.98), respectively. Although the difference was not significant, the sensitivity was lower in patients with lower PSA levels: 0.63 vs. 0.89; p=.13. A significant correlation was found between the SUVmax of both tracers (r = 0.41, n = 130, p <.0001). CONCLUSIONS: 68Ga-DOTATATE PET/CT and 11C-choline PET/CT seem to have a high capacity to detect pathological lesions in the assessment of patients with prostate cancer with biochemical relapse. Further studies are required to test the potential complementary value of these PET/CT techniques, and to evaluate the potential role of 8Ga-DOTATATE for planning somostatin receptor-mediated therapies (177Lu-DOTATATE).

Incidental focal colonic uptake in studies 18F-FDG PET/CT. / Hallazgo incidental de captación focal del colon en estudios 18F-FDG PET/TC.

OBJECTIVES: To assess the frequency of focal colonic uptake as an incidental observation in 18F-FDG PET/CT studies, and to correlate this finding with histopathological results. MATERIAL AND METHODS: Out of a total of 3,176 PET/CT studies with 18F-FDG systematic analysis was carried out on 30 studies in which colonic focal uptake was observed. Patients with known colorectal neoplasia were excluded. The maximum standardised uptake values (SUVm) and the morphological findings provided by the CT were recorded. The studies were reported by a radiologist and a nuclear medicine doctor. The findings were compared with endoscopy and pathology findings. RESULTS: Of the 30 patients with focal hypermetabolic lesions of the colon (0.94%), 15 were men and 15 were women with ages between 27 and 73 (mean 55 years). The reasons for PET/CT were bronchopulmonary cancer (4), breast cancer (4), tumour of unknown origin (4), melanoma (3), renal carcinoma (3), cervical neoplasia (2), adenocarcinoma of ovary (2), and others (8). Of the 23 colonoscopies performed, 10 patients (43.4%) had malignant lesions, 6 (26.1%) had pre-malignant lesions, and in 7 patients (30.4%) no lesion was identified or was benign. No endoscopy was performed on 7 patients for various reasons (patient refusal to perform the study, advanced oncological disease). An analysis was performed with the SUVm, with no statistically significant differences being found between malignant-premalignant lesions and benign lesions. CONCLUSIONS: Focal uptake in the colon of 18F-FDG has clinical relevance, and is mainly associated with morphological lesions in CT. It should be evaluated, as it may be a second tumour or a pre-malignant lesion. It is recommended that all focal uptakes of the colon be evaluated with endoscopy.

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.

Influence of copigmentation and phenolic composition on wine color.

Chromatic characteristics and their relationships with copigmentation and phenolic composition were studied in 160 bottled red wines. Free anthocyanins, copigmented anthocyanins and polymeric pigments contributing to color were calculated according to Boulton protocol and related to main changes produced in wine visible spectra after destroying any copigmented anthocyanins effect. Color differences between copigmented and non copigmented wines were quantified and related with ageing, cultivar and phenolic profile. Phenomenon of co-pigmentation visually increases the colour at 420, 520 and 620 nm for most of wines. Copigmented wines showed a mean value of 8.26 CIELab units higher than non copigmented (ΔEab(c-nc)), being this shift deeper for young wines than for aged wines. Copigmentation mostly changed hue and decreased L, a* and b* values therefore resulted into purplish and darker wine. Visual variations in color caused by copigmentation was related to particularly anthocyanins and copigments (mostly flavonols and hydroxycinnamic acids).

Effects of low intensity vibration on bone and muscle in rats with spinal cord injury.

UNLABELLED: Spinal cord injury (SCI) causes rapid and marked bone loss. The present study demonstrates that low-intensity vibration (LIV) improves selected biomarkers of bone turnover and gene expression and reduces osteoclastogenesis, suggesting that LIV may be expected to benefit to bone mass, resorption, and formation after SCI. INTRODUCTION: Sublesional bone is rapidly and extensively lost following spinal cord injury (SCI). Low-intensity vibration (LIV) has been suggested to reduce loss of bone in children with disabilities and osteoporotic women, but its efficacy in SCI-related bone loss has not been tested. The purpose of this study was to characterize effects of LIV on bone and bone cells in an animal model of SCI. METHODS: The effects of LIV initiated 28 days after SCI and provided for 15 min twice daily 5 days each week for 35 days were examined in female rats with moderate severity contusion injury of the mid-thoracic spinal cord. RESULTS: Bone mineral density (BMD) of the distal femur and proximal tibia declined by 5 % and was not altered by LIV. Serum osteocalcin was reduced after SCI by 20 % and was increased by LIV to a level similar to that of control animals. The osteoclastogenic potential of bone marrow precursors was increased after SCI by twofold and associated with 30 % elevation in serum CTX. LIV reduced the osteoclastogenic potential of marrow precursors by 70 % but did not alter serum CTX. LIV completely reversed the twofold elevation in messenger RNA (mRNA) levels for SOST and the 40 % reduction in Runx2 mRNA in bone marrow stromal cells resulting from SCI. CONCLUSION: The findings demonstrate an ability of LIV to improve selected biomarkers of bone turnover and gene expression and to reduce osteoclastogenesis. The study indicates a possibility that LIV initiated earlier after SCI and/or continued for a longer duration would increase bone mass.

Postinjury treatment with rolipram increases hemorrhage after traumatic brain injury.

The pathology caused by traumatic brain injury (TBI) is exacerbated by the inflammatory response of the injured brain. Two proinflammatory cytokines that contribute to inflammation after TBI are tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß). From previous studies using the parasagittal fluid-percussion brain injury model, we reported that the anti-inflammatory drug rolipram, a phosphodiesterase 4 inhibitor, reduced TNF-α and IL-1ß levels and improved histopathological outcome when administered 30 min prior to injury. We now report that treatment with (±)-rolipram given 30 min after injury significantly reduced TNF-α levels in the cortex and hippocampus. However, postinjury administration of (±)-rolipram significantly increased cortical contusion volume and increased atrophy of the cortex compared with vehicle-treated animals at 10 days postinjury. Thus, despite the reduction in proinflammatory cytokine levels, histopathological outcome was worsened with post-TBI (±)-rolipram treatment. Further histological analysis of (±)-rolipram-treated TBI animals revealed significant hemorrhage in the contused brain. Given the well-known role of (±)-rolipram of increasing vasodilation, it is likely that (±)-rolipram worsened outcome after fluid-percussion brain injury by causing increased bleeding.

(99m)Tc glucarate as a potential radiopharmaceutical agent for assessment of tumor viability: from bench to the bed side.

Several radiotracers have been used for assessing cell death, whether by necrosis or apoptosis. (99m)Tc glucarate, which has initially been reported to be concentrating/accumulating in myocardial infarction or zones of cerebral injury, has also shown some tumor-seeking properties in a few preliminary studies. Under International Atomic Energy Agency (IAEA)'s coordinated research program, we report here the standardization, quality control, and clinical evaluation (detection, evaluation of response, and comparison with (18)F Fluorodeoxyglucose) of this tracer in well-characterized lung cancer and head neck malignancies in a single-arm prospective observational study. Forty-seven patients (29 inoperable lung carcinoma and 18 head and neck malignancies) were prospectively enrolled and underwent (99m)Tc glucarate imaging [whole body planar and single-photon emission computed tomography of the region of interest] 4-5 hours after injection of 20 mCi of the radiopharmaceutical. Excellent (99m)Tc glucarate concentration was noted in the target lesion in lung cancer and head and neck malignancies. The sensitivity was found to be better in lung cancer. Avid concentration of tracer was seen in the metastatic sites. During response evaluation, the glucarate concentration correlated well with the clinical and other radiological findings. (99m)Tc glucarate showed avid concentration of tracer in the tumor, suggesting it to be a potential tumor imaging agent which can be used for detection and assessment of therapeutic response in malignancy.

[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.

Effects of simvastatin on systemic inflammatory responses after cardiopulmonary bypass.

AIM: Cardiopulmonary bypass is associated with a complex systemic inflammatory response and the extent of their increase has been correlated with the development of postoperative complications. Recent studies suggest that treatment with statins is associated with a significant and marked decrease in inflammation-associated variables such as cytokines. Therefore, we investigated the effects of preoperative simvastatin treatment on systemic inflammatory response and perioperative morbidity after cardiopulmonary bypass. METHODS: A prospective, randomized study, was designed. Forty-four subjects undergoing elective coronary artery bypass grafting who fulfilled the inclusion criteria were randomized to treatment with simvastatin (20 mg/day, group A, N. 22) or control (group B, N. 22) before surgery. Plasma levels of interleukins (IL-6, IL-8, TNF-alpha), and systemic inflammatory response score (SIRS) were measured during the surgical intervention and over the following 48 postoperative hours. Cytokine levels were measured by enzyme-linked assays from plasma samples obtained at specific time points pre- and post-operation. RESULTS: In both groups the serum levels of the proinflammatory cytokines (IL-6, IL-8, TNF-alpha), and leukocytes, and the SIRS score increased significantly over the baseline, though no significant differences were observed between the two groups. The preoperative and postoperative course did not differ between both groups. CONCLUSIONS: In patients undergoing coronary artery bypass grafting with cardiopulmonary bypass, the administration of simvastatin doses not produce any changes in the inflammatory response as measured by the levels of IL-6, IL-8, TNF-alpha and SIRS score, nor does it reduce the complications after cardiac surgery.

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.

The inflammatory response to colloids and crystalloids used for pump priming during cardiopulmonary bypass.

BACKGROUND: Systemic inflammatory response frequently occurs after coronary artery bypass surgery and is strongly correlated with the risk of postoperative morbidity and mortality. This study tests the hypothesis that the priming of the extracorporeal circuit with colloid solutions results in less inflammation in patients undergoing cardiac surgery than priming with crystalloid solutions. METHODS: A prospective, randomized study was designed. Forty-four patients undergoing elective coronary artery bypass grafting were randomly allocated to one of two groups: 22 patients primed with Ringer's lactate (RL) solution and 22 patients primed with gelatin-containing solution during the surgery. Plasma levels of interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-alpha, C-reactive protein (CRP) and, complement 4 were measured during the surgical intervention and over the following 48 postoperative hours. Cytokine levels were measured by enzyme-linked assays from plasma samples obtained at specific time points pre- and post-operatively. RESULTS: In both groups the serum levels of the pro-inflammatory cytokines (IL-6, IL-8, TNF-alpha), CRP, complement 4, and leukocytes increased significantly over the baseline, although no significant differences were observed between the two groups. The operation time, blood loss, need for inotropic support, extubation time, and length of intensive care unit stay did not differ significantly between the two groups. CONCLUSION: Priming with gelatin vs. RL produces no significant differences in the inflammatory response in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass.

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.