B and T Lymphocyte Densities Remain Stable With Age in Human Cortex.

One hallmark of human aging is increased brain inflammation represented by glial activation. With age, there is also diminished function of the adaptive immune system, and modest decreases in circulating B- and T-lymphocytes. Lymphocytes traffic through the human brain and reside there in small numbers, but it is unknown how this changes with age. Thus we investigated whether B- and T-lymphocyte numbers change with age in the normal human brain. We examined 16 human subjects in a pilot study and then 40 human subjects from a single brain bank, ranging in age from 44-96 years old, using rigorous criteria for defining neuropathological changes due to age alone. We immunostained post-mortem cortical tissue for B- and T-lymphocytes using antibodies to CD20 and CD3, respectively. We quantified cell density and made a qualitative assessment of cell location in cortical brain sections, and reviewed prior studies. We report that density and location of both B- and T-lymphocytes do not change with age in the normal human cortex. Solitary B-lymphocytes were found equally in intravascular, perivascular, and parenchymal locations, while T-lymphocytes appeared primarily in perivascular clusters. Thus, any change in number or location of lymphocytes in an aging brain may indicate disease rather than normal aging.

Microstructure of Human Corpus Callosum across the Lifespan: Regional Variations in Axon Caliber, Density, and Myelin Content.

The myeloarchitecture of the corpus callosum (CC) is characterized as a mosaic of distinct differences in fiber density of small- and large-diameter axons along the anterior-posterior axis; however, regional and age differences across the lifespan are not fully understood. Using multiecho T2 magnetic resonance imaging combined with multi-T2 fitting, the myelin water fraction (MWF) and geometric-mean of the intra-/extracellular water T2 (geomT2IEW) in 395 individuals (7-85 years; 41% males) were examined. The approach was validated where regional patterns along the CC closely resembled the histology; MWF matched mean axon diameter and geomT2IEW mirrored the density of large-caliber axons. Across the lifespan, MWF exhibited a quadratic association with age in all 10 CC regions with evidence of a positive linear MWF-age relationship among younger participants and minimal age differences in the remainder of the lifespan. Regarding geomT2IEW, a significant linear age × region interaction reflected positive linear age dependence mostly prominent in the regions with the highest density of small-caliber fibers-genu and splenium. In all, these two indicators characterize distinct attributes that are consistent with histology, which is a first. In addition, these results conform to rapid developmental progression of CC myelination leveling in middle age as well as age-related degradation of axon sheaths in older adults.

Early neutrophil count relates to infarct size and fatal outcome after large hemispheric infarction.

AIMS: To investigate the relationship between peripheral leukocyte dynamics and the outcome of large hemispheric infarction (LHI) patients. METHODS: Patients with acute LHI admitted to the neuro-intensive care unit of Xuanwu Hospital from 2013 to 2017 were prospectively enrolled and followed up for 6 months after LHI. RESULTS: A total of 84 LHI patients were included, 38 patients suffered brain herniation and 20 patients died from stroke. Compared to patients with benign course, LHI patients with fatal outcome showed larger infarcts and more severe brain edema (P < .01), as well as increased WBC and neutrophil counts throughout the first week after stroke (P < .05). Correlation analysis revealed that neutrophil counts on D2 after LHI positively correlated with infarct and edema volumes measured from CT/MRI (R2  = 0.22 and R2  = 0.15, P < .01) and negatively correlated with Glasgow Coma Scale (ρ = -0.234, P < .05). Patients with D2 neutrophils > 7.14 × 109 /L had higher risk of brain herniation [odds ratio (OR) = 7.5, 95% CI: 2.0-28.1, P = .001], and patients with D2 neutrophils > 7.79 × 109 /L had a higher risk of death (OR = 5.8, 95% CI: 1.2-27.0, P = .015). CONCLUSION: Early peripheral neutrophil count after stroke relates to infarct size and the fatal outcome of LHI patients, which might help guiding acute LHI management such as reduction of intracranial pressure and potential antiinflammatory therapy in the future.

Características de la córnea donante mediante microscopia endotelial / Donor cornea characterization by endothelial microscopy

RESUMEN Objetivo: Determinar las características del endotelio corneal mediante microscopia endotelial. Métodos: Se realizó un estudio descriptivo y retrospectivo en córneas donantes del banco de ojos del Instituto Cubano de Oftalmología "Ramón Pando Ferrer" en el período de enero a junio del año 2019. La muestra estuvo conformada por 224 córneas donantes. Las variables del estudio fueron: edad, cirugías previas, gerontoxón, pterigion, defectos epiteliales, infiltrado corneal, opacidad corneal, edema, pigmentos endoteliales, guttas, desprendimiento de la Descemet, densidad celular, hexagonalidad y polimegatismo. Resultados: El gerontoxon fue el hallazgo más frecuente (56,69 por ciento); la densidad celular media fue de 2 501 cel/mm2; el coeficiente de variación medio fue 43,32 y la hexagonalidad media 50,02. La densidad celular endotelial entre 2 000 y 2 500 cel/mm2 fue más frecuente entre 60 y 79 años de edad (76,72 por ciento), mientras que entre 20 y 29 años todas las córneas donantes presentaron una densidad endotelial mayor de 2 500 cel/mm2. Conclusiones: En el examen biomicroscópico de la córnea donante fue más frecuente el gerontoxon. Por microscopia endotelial la mayoría de las córneas fueron aptas para trasplante corneal. Un endotelio corneal con densidad celular mayor de 2 500 cel/mm2 no es exclusivo de córneas con menos de 60 años de edad(AU)

ABSTRACT Objective: Determine the characteristics of the corneal endothelium by endothelial microscopy. Methods: A retrospective descriptive study was conducted of donor corneas from the eye bank of Ramón Pando Ferrer Cuban Institute of Ophthalmology from January to June 2019. The sample was 224 donor corneas. The variables analyzed were age, previous surgery, gerontoxon, pterygium, epithelial defects, corneal infiltrate, corneal opacity, edema, endothelial pigments, guttae, Descemet's membrane detachment, cell density, hexagonality and polymegethism. Results: Gerontoxon was the most common finding (56.69 percent), mean cell density was 2 501 cell/mm2, mean variation coefficient was 43.32 and mean hexagonality was 50.02. Endothelial cell density from 2 000 to 2 500 cell/mm2 was more common in the 60-79 years age group (76.72 percent), whereas in the 20-29 years age group all the donor corneas had an endothelial density above 2 500 cell/mm2. Conclusions: Gerontoxon was the most common finding in the biomicroscopic examination of the cornea. Endothelial microscopy found that most corneas were suitable for corneal transplantation. A corneal endothelium with a cell density above 2 500 cell/mm2 is not exclusive of corneas under 60 years of age(AU)

Mice With Decreased Number of Interneurons Exhibit Aberrant Spontaneous and Oscillatory Activity in the Cortex.

GABAergic (γ-aminobutyric acid) neurons are inhibitory neurons and protect neural tissue from excessive excitation. Cortical GABAergic neurons play a pivotal role for the generation of synchronized cortical network oscillations. Imbalance between excitatory and inhibitory mechanisms underlies many neuropsychiatric disorders and is correlated with abnormalities in oscillatory activity, especially in the gamma frequency range (30-80 Hz). We investigated the functional changes in cortical network activity in response to developmentally reduced inhibition in the adult mouse barrel cortex (BC). We used a mouse model that displays ∼50% fewer cortical interneurons due to the loss of Rac1 protein from Nkx2.1/Cre-expressing cells [Rac1 conditional knockout (cKO) mice], to examine how this developmental loss of cortical interneurons may affect basal synaptic transmission, synaptic plasticity, spontaneous activity, and neuronal oscillations in the adult BC. The decrease in the number of interneurons increased basal synaptic transmission, as examined by recording field excitatory postsynaptic potentials (fEPSPs) from layer II networks in the Rac1 cKO mouse cortex, decreased long-term potentiation (LTP) in response to tetanic stimulation but did not alter the pair-pulse ratio (PPR). Furthermore, under spontaneous recording conditions, Rac1 cKO brain slices exhibit enhanced sensitivity and susceptibility to emergent spontaneous activity. We also find that this developmental decrease in the number of cortical interneurons results in local neuronal networks with alterations in neuronal oscillations, exhibiting decreased power in low frequencies (delta, theta, alpha) and gamma frequency range (30-80 Hz) with an extra aberrant peak in high gamma frequency range (80-150 Hz). Therefore, our data show that disruption in GABAergic inhibition alters synaptic properties and plasticity, while it additionally disrupts the cortical neuronal synchronization in the adult BC.

Glucocorticoid receptor activation induces decrease of hippocampal astrocyte number in rats.

RATIONALE: The decrease of astrocyte number and hypothalamic-pituitary-adrenal (HPA) axis overactivity are observed in individuals with major depressive disorder. Elevated levels of glucocorticoids induced by hyperactivation of the HPA axis may result in glucocorticoid receptor (GR) activation. However, it is unclear whether there is a direct link between GR activation and the decrease of astrocyte number. METHODS: Animals were exposed to chronic unpredictable stress (CUS) for 28 days and treated with continuous subcutaneous injections of vehicle or corticosterone (CORT; 40 mg/kg/day) for 21 days. We then administered mifepristone on day 21 after CUS and on day 18 after the CORT treatment. We observed behavioral deficits in the sucrose preference test, open field test, and forced swim test. Protein expression was analyzed using immunofluorescence (IF) and western blot (WB). RESULTS: Animals exposed to CUS exhibited behavioral deficits in tests measuring anhedonia, anxiety, and despair state. They also had decreases in glial fibrillary acidic protein (GFAP) expression and numbers of GFAP-positive cells in the hippocampus. The behavioral and cellular alterations induced by CUS were reversed by subchronic treatment with the GR antagonist mifepristone. We also found that the subcutaneous injection of glucocorticoids may induce depression-like behavior and reduce GFAP protein expression in rats, which was similarly reversed by mifepristone. CONCLUSIONS: These findings provide experimental evidence that GR activation due to elevated CORT levels induces the decrease of hippocampal astrocyte number in rats.

High Frequency of Tc22 and Th22 Cells in Myasthenia Gravis Patients and Their Significant Reduction after Thymectomy.

OBJECTIVES: Myasthenia gravis (MG) is an autoimmune disease accompanied by a thymic pathology and in most patients thymectomy (TE) is used as the therapeutic approach. Both B and T cells play an important role in MG pathogenesis. METHODS: Twelve pre- and post-TE MG patients and 12 healthy controls (HCs) were enrolled. The mean percentages of Th22 and Tc22 cells were evaluated in MG patients (before and 6 months after TE) and HCs. RESULTS: The mean percentage of Tc22 cells in pre-TE patients was significantly higher than in HCs (p < 0.05), and after TE Tc22 cells significantly decreased compared to pre-TE (p < 0.05). The frequency of Th22 cells in pre-TE MG patients was not significantly different from HCs, but after TE Th22 cells were significantly decreased compared to pre-TE (p < 0.05). CONCLUSION: Our findings suggest a possible role of Th22 and Tc22 in MG pathogenesis.

Magnitudes biológicas que tiene interés medir de modo urgente / Biological markers in emergency laboratory

No disponible

Citotoxicidad del 1-O-undecilglicerol sobre células de mama humanas mediante análisis de células en tiempo real / Cytotoxicity of 1-O-undecylglycerol in human breast cells by Real Time Cell Analysis

Objetivos: Estudiar el efecto del 1-O-undecilglicerol sobre la proliferación de células de cáncer de mama MCF-7 y de mama normales 184B5. Métodos: Se realizó seguimiento a tiempo real de la viabilidad de ambas líneas celulares, con empleo del analizador de células en tiempo real. Se determinó la densidad celular apropiada para el estudio, y se trataron las células con dos concentraciones de 1-O-undecilglicerol durante 48 horas. Se compararon las pendientes del índice celular en cada experimento. Resultados: El 1-O-undecilglicerol redujo significativamente la proliferación de las células MCF-7, mientras que fue poco citotóxico sobre las células 184B5 hasta 75μM. A la concentración de 150μM fue citotóxico para ambas líneas, pero invirtió la pendiente del índice celular de las células de cáncer de mama. Conclusiones: El 1-O-undecilglicerol podría ser candidato para futuros estudios en modelos in vivo de cáncer de mama, así como para la profundización en el mecanismo involucrado en este efecto

Aim: To study the effect of 1-O-undecylglycerol on the proliferation of human breast cancer cells MCF-7 and 184B5 normal breast cells. Methods: Real time following of both cell lines was performed, by Real Time Cell Analyzer. Appropriated cell density was selected, and cells were treated with two concentrations of 1-O-undecylglycerol for 48 hours. Cell index slopes were compared in each experiment. Results: 1-O-undecylglycerol induced significant reduction of MCF-7 cell viability, and was less cytotoxic on 184B5 cells with 75μM. At 150μM was cytotoxic for both lines, but cell index slope of breast cancer cells was negative. Conclusion: 1-O-undecilglicerol could be a candidate for future studies in in vivo models of breast cancer, and for further experiments about the mechanism involved in this effect

Biphasic response in number of stem cells and endothelial progenitor cells after left ventricular assist device implantation: A 6month follow-up.

BACKGROUND: Continuous blood flow could have deleterious effects on endothelium and vascular health. This could have serious consequences in patients with heart failure treated with continuous flow left ventricular assist devices (LVAD). Therefore, we studied effect of LVAD on three circulating vascular biomarkers: stem cells (SC), endothelial progenitor cells (EPC) and microparticles (MP). METHODS: In 23 patients (5 women) with end-stage heart failure, SC, EPC and MP were measured before, and 3 and 6months after implantation of LVAD (HeartMate II). SC were defined using determination of surface antigen expression as mononuclear CD34+/CD45low+ cells and EPC as mononuclear CD34+/CD45low+/KDR+ cells. MP concentrations were determined by ELISA method. RESULTS: Three months after LVAD implantation numbers of SC and EPC significantly decreased (p=0.01 and p=0.001, respectively). On the contrary, between 3rd and 6th month after implantation they significantly increased (p=0.006 and p=0.003, respectively).MP did not change significantly during the study despite exerting similar trend as SC and EPC. CONCLUSIONS: Observed biphasic changes of SC and EPC might reflect two processes. First, shortly after LVAD implantation, improved tissue perfusion could lead to decrease in ischemic stimuli and ensuing decrease of SC and EPC. Second, continuous flow between 3rd and 6th month produced by LVAD could lead to increase of SC and EPC through activation of endothelium. This explanation could be supported also by similar trend in the changes of concentrations of MP.

Human Traumatic Brain Injury Results in Oligodendrocyte Death and Increases the Number of Oligodendrocyte Progenitor Cells.

Oligodendrocyte (OL) death may contribute to white matter pathology, a common cause of network dysfunction and persistent cognitive problems in patients with traumatic brain injury (TBI). Oligodendrocyte progenitor cells (OPCs) persist throughout the adult CNS and may replace dead OLs. OL death and OPCs were analyzed by immunohistochemistry of human brain tissue samples, surgically removed due to life-threatening contusions and/or focal brain swelling at 60.6 ± 75 hours (range 4-192 hours) postinjury in 10 severe TBI patients (age 51.7 ± 18.5 years). Control brain tissue was obtained postmortem from 5 age-matched patients without CNS disorders. TUNEL and CC1 co-labeling was used to analyze apoptotic OLs, which were increased in injured brain tissue (p < 0.05), without correlation with time from injury until surgery. The OPC markers Olig2, A2B5, NG2, and PDGFR-α were used. In contrast to the number of single-labeled Olig2, A2B5, NG2, and PDGFR-α-positive cells, numbers of Olig2 and A2B5 co-labeled cells were increased in TBI samples (p < 0.05); this was inversely correlated with time from injury to surgery (r = -0.8, p < 0.05). These results indicate that severe focal human TBI results in OL death and increases in OPCs postinjury, which may influence white matter function following TBI.

Seasonal trends in milk quality in Ireland between 2007 and 2011.

The objectives of this study were to evaluate annual and seasonal trends in bulk tank somatic cell count (SCC), total bacterial count (TBC), and laboratory pasteurization count (LPC) in Ireland between 2007 and 2011 (inclusive), and to compare trends based on herd type and herd size. The unadjusted median SCC and TBC of all records were 266,000 and 17,000 cfu/mL, respectively. Data were transformed to log values and analyzed using a mixed model. Fixed effects included milk processor, year, month, and total monthly milk volume; milk producer was fitted as a random variable. After analysis, means were back transformed for interpretation. Annual SCC increased slightly from 259,000 cells/mL in 2007 to a peak of 272,647 cells/mL in 2009 and then declined slightly thereafter. Although statistically significant changes in annual TBC are probably not biologically relevant, values ranged between 23,922 and 26,290 cfu/mL. Annual LPC peaked in 2008 (265 cfu/mL), declined in 2009, and increased thereafter. Monthly mean SCC of all records increased from April onward, with the greatest increases seen from October to December, when the majority of cows entered late lactation. Monthly mean TBC exhibited a seasonal trend, whereby TBC was greatest at the beginning and end of the year, coinciding with winter housing. Seasonal milk production herds (n=8,002 herds) calve all cows in spring (February to April), whereas split-calving herds (n=1,829 herds) calve cows in the spring and autumn. From February to September, monthly SCC was lower for seasonal herds than for split-calving herds, whereas SCC was lower for split-calving herds for the remaining months. During winter (October to March), split-calving herds had lower monthly TBC than seasonal herds, most likely because of stricter regulations imposed upon them. Herd size was approximated using total annual milk production figures. Across all months, larger herds had lower SCC and TBC compared with smaller herds. No obvious improvements in milk quality were seen between 2007 and 2011. Farmers have the opportunity to improve milk quality by reducing bulk tank SCC in late lactation and by imposing stricter hygiene practices at the beginning and end of the year to overcome the seasonal variation of bulk tank TBC.

Loss of Glial Cells of the Hippocampus in a Rat Model of Post-traumatic Stress Disorder.

Single prolonged stress (SPS) rats is a rodent model of post traumatic stress disorder (PTSD). Abnormal hippocampal morphology and function were found in the PTSD patients. Our previous study has shown that SPS induce loss of hippocampal neurons. But the effects of SPS on glial cells in the hippocampus have not been evaluated. In the present study, wistar male rats were examined at 1, 4, 7, or 14 days after SPS. The morris water maze were performed to examine hippocampal-dependent cognition. The neurometabolite and morphological change in the hippocampal neurons and glial cells were investigated using in vivo proton magnetic resonance spectroscopy and transmission electron microscopy. Immunofluorescence histochemistry and western blotting for Glial fibrillary acidic protein (GFAP) was used to evaluate change of astrocytes. SPS rats showed increased escape latency. The significant reductions in N-acetylaspartate, creatine, and choline-containing compounds in the hippocampus of SPS rats were found. Moreover, abnormal morphological characteristics in glial cells of the SPS group were observed. The number of GFAP-positive cells, intensity of GFAP-ir and GFAP-protein within the hippocampus increased after SPS at 1 day, and then decreased. The findings suggested that SPS induced loss/impairment of glial cell in the hippocampus; also loss of glial cells may due to the astrocytes reduction within the hippocampus of SPS rats.

¿Es útil la reevaluación de cristales en el líquido sinovial? / Reassessment of crystals in synovial fluid: is it helpful?

Introducción. El recuento celular, el análisis de cristales y el estudio microbiológico del líquido sinovial (LS), son piezas claves en el diagnóstico y manejo del derrame articular pues conducen a decisiones clínicas y terapéuticas. El análisis de cristales suele realizarse en campo claro y con luz polarizada compensada (LPC). Depende de la experiencia del examinador y del número de cristales presentes. Para aumentar el rendimiento, se puede analizar el sedimento tras centrifugación. Hay autores que sugieren que la maduración in vitro de los cristales facilita su identificación tras 24 horas de la extracción. Otros sugieren que dicha demora deteriora la muestra. Nuestro objetivo es valorar si el re-examen del LS a las 24 horas puede aumentar el rendimiento diagnóstico para cristales. Material y métodos. Se analizaron durante 4 meses las muestras de LS remitidas para su análisis con LP y microscopía de campo claro; se realizó reevaluación a las 24 horas en todos los casos posibles. Resultados. Recibimos 174 LS, de los cuales 138 (79,3%) fueron negativos para el primer análisis y 36 positivos. En 84 casos (60,8%) se pudo realizar una evaluación a las 24 horas. En 10 casos (11,9%) se observaron cristales que no habían sido vistos en el primer análisis. Siempre se trató de cristales de pirofosfato cálcico dihidratado. El incremento de muestras positivas tras el segundo examen fue de un 27,8% (IC 95%: 13,1-42,4). Conclusión. El reanálisis de cristales en LS a las 24 horas debe considerarse en los casos de sospecha de artropatía microcristalina con primer examen negativo (AU)

Background. White blood cell counts, analysis of crystals in synovial fluid (SF) and microbiological studies are key measurements in the diagnosis and management of joint effusion. The results may lead to clinical and therapeutic decisions. The diagnosis of crystals in SF, usually performed by examination with compensated polarised light microscopy (PL), is not easy. It depends on the experience of the examiner and amount of crystals in the sample, which is sometimes very small. In order to increase the performance, analysis may be performed on the sediment after centrifugation. Some authors suggest that due to in vitro maturation of crystals, they can be more easily identified 24hours after extraction. Others suggest that the sample deteriorates. We question whether re-examination of SF can increase the diagnostic yield of this test. Methods. Over a 4 month period we analysed crystals in SF received in the laboratory using a PL and ordinary light microscopy. Where this was possible, the SF was examined again after 24hours. Results. We received 174 SF; 138 (79.3%) were negative for the first analysis. In 84 cases (60.8%) a re-evaluation could be made after 24hours by trained staff. In 10 cases (11.9%) crystals that had not been seen previously became apparent. In all cases they were calcium pyrophosphate dihydrate crystals. The number of positive fluids increased by 27.8% (95% CI: 13.1-42.4) after a second assay. Conclusions. The re-analysis of crystals in SF at 24hours should be considered in cases of high suspicion of microcrystalline arthropathy when the first test is negative (AU)

Flow cytometric analysis of micronuclei in mammalian cell cultures: past, present and future.

The relative simplicity of the in vitro micronucleus (MNvit) endpoint has made it amenable to several automated scoring approaches. Flow cytometry is one such scoring platform that has been successfully employed. This review describes the origins of the MNvit assay, as well as the evolution and properties of flow cytometry-based scoring systems. While the current state-of-the-art methods acquire micronucleus (MN) frequency data very efficiently, it is becoming clear that they also endow the assay with high information content. For instance, simultaneous with MN frequency determinations, several additional endpoints are acquired that provide insights into cytotoxicity, cell cycle perturbations and, in the event of MN induction, information about genotoxic mode of action. This review concludes with a discussion regarding data gaps and also recommendations for additional work that is needed to more fully realise the potential of flow cytometric MNvit scoring.

Involvement of insulin-like growth factor-I for the regulation of prolactin synthesis by estrogen and postnatal proliferation of lactotrophs in the mouse anterior pituitary.

Estradiol (E2) stimulates not only secretion of prolactin (PRL) and proliferation of PRL-producing cells (PRL cells) in the anterior pituitary, but also the expression of growth factors. In insulin-like growth factor-I (IGF-I) knockout (KO) mice, the number of PRL cells is decreased and administration of IGF-I does not increase either the number of PRL cells or plasma PRL levels, indicating that IGF-I plays a pivotal role in PRL cells. The effect of E2 on PRL cells in KO mice was investigated by immunohistochemistry and real-time RT-PCR. The number of PRL cells in KO mice was significantly lower than in the wild-type (WT) control mice. E2 increased the PRL mRNA in WT and KO mice; however, an increase of PRL mRNA in KO was less than that in WT. In addition, no vasoactive intestinal peptide (VIP)-immunoreactive cells were found in KO mice, therefore IGF-I is essential for VIP expression. To investigate the roles of IGF-I on PRL cells in the postnatal development, double-immunostaining with PRL and BrdU was performed in WT and KO mice from days 5-20. The percentages of PRL cells and BrdU-labeled cells in the anterior pituitary of KO mice were lower than in WT mice. Thus, IGF-I may be responsible for proliferation and differentiation of PRL cells in this postnatal period. Differentiation and the proliferation of PRL cells are controlled by IGF-I during the postnatal development, and IGF may be a mediator of E2 action through VIP induction in PRL cells of adults.

Regulatory T cells in systemic lupus erythematosus: past, present and future.

Regulatory/suppressor T cells (Tregs) maintain immunologic homeo-stasis and prevent autoimmunity. In this article, past studies and recent studies of Tregs in mouse models for lupus and of human systemic lupus erythematosus are reviewed concentrating on CD4+CD25+Foxp3+ Tregs. These cells consist of thymus-derived, natural Tregs and peripherally induced Tregs that are similar phenotypically and functionally. These Tregs are decreased in young lupus-prone mice, but are present in normal numbers in mice with established disease. In humans, most workers report CD4+Tregs are decreased in subjects with active systemic lupus erythematosus, but the cells increase with treatment and clinical improvement. The role of immunogenic and tolerogenic dendritic cells in controlling Tregs is discussed, along with new strategies to normalize Treg function in systemic lupus erythematosus.

Del hemograma manual al hemograma de cuarta generación / From blood manual blood fourth generation

El hemograma o cuadro hemático es una de las pruebas que más se solicita al laboratorio clínico, y sin duda alguna, la prueba de laboratorio que más aporta al clínico en la evaluación de un paciente. Desde el punto de vista técnico se reconocen seis tipos de hemograma, que van desde los tradicionales que se hacen con métodos manuales hasta los más sofisticados que se hacen con métodos electrónicos que utilizan una combinación detecnologías. Se establecen los criterios que definen los tipos de hemograma y se analizan los parámetros desde el punto de vista metodológico, los valores de referencia, las indicaciones clínicas y los aspectos críticos de cada parámetro de acuerdo con la metodología utilizada.El médico debe solicitar el hemograma que le permita tener mayor certeza analítica posible en los parámetros reportados y el laboratorio clínico debe hacer la inversión tecnológica que le permita ofrecer resultados lo más precisos y exactos posible. Palabras clave: hemograma, cuadro hemático, recuento de células, laboratorio, utilidad clínica, valores de referencia.

Validity of bioluminescence measurements for noninvasive in vivo imaging of tumor load in small animals.

A relatively new strategy to longitudinally monitor tumor load in intact animals and the effects of therapy is noninvasive bioluminescence imaging (BLI). The validity of BLIf or quantitative assessment of tumor load in small animals is critically evaluated in the present review. Cancer cells are grafted in mice or rats after transfection with a luciferase gene--usually that of a firefly. To determine tumor load, animals receive the substrate agent luciferin intraperitoneally, which luciferase converts into oxyluciferin in an ATP-dependent manner Light emitted by oxyluciferin in viable cancer cells is captured noninvasively with a highly sensitive charge-coupled device (CCD) camera. Validation studies indicate that BLI is useful to determine tumor load in the course of time, with each animal serving as its own reference. BLI is rapid, easy to perform, and sensitive. It can detect tumor load shortly after inoculation, even when relatively few cancer cells (2500-10,000) are used. BLI is less suited for the determination of absolute tumor mass in an animal because of quenching of bioluminescence by tissue components and the exact location of tumors because its spatial resolution is limited. Nevertheless, BLI is a powerful tool for high-throughput longitudinal monitoring of tumor load in small animals and allows the implementation of more advanced orthotopic tumor models in therapy intervention studies with almost the same simplicity as when measuring traditional ectopic subcutaneous models in combination with calipers.