Evidence for a stimulatory effect of high potassium diet on renal kallikrein

Evidence for stimulatory effect of high potassium diet on renal kallikrein. Considerable evidence indicates that the connecting tubule cells, a type of cell of the distal nephron which seems to participate on potassium secretion, may be the place where renal kallikrein is synthetized. As potassium secretion and kallikrein synthesis may occur in the same cells, we studied the effect of high potassium diet on renal kallikrein production. The kallikrein containing cells from rats fed a normal and high potassium diet were evaluated using a combination of morphometric analysis, conventional electron microscopy, and ultrastructural immunocytochemistry. High potassium diet produced hypertrophy and hyperplasia of the kallikrein containing cells. Hyperplasia was sustained by an increased number of immunoreactive cells/mm2 (151 ± 14 vs. 86.4 ± 12, P < 0.01), an increased number of binucleated immunoreactive cells/mm2 (11.90 ± 2.1 vs. 3.77 ± 0.17, P < 0.005), and by the presence of mitosis. Cell hypertrophy was sustained by an increased cross–sectional area of immunoreactive cells (µ2) (320.4 ± 21 vs. 104.5 ± 6.1, P < 0.001), by an increased area of basal plasma membrane infoldings, by an hypertrophy of the components of the Golgi complex, hypertrophy of the components of the rough endoplasmic reticulum, and by a larger number of secretory–like vesicles containing kallikrein. The rats fed with high potassium diet had higher values on urinary kallikrein excretion–amidase activity (3.70 ± 0.51 vs. 2.01 ± 0.37 units/day, P < 0.02), higher values on potassium excretion (18.8 ± 1.7 vs. 1.31 ± 0.1 mmol/day, P < 0.001), and higher urinary volume (51.5 ± 5.3 vs. 12.2 ± 1.6 ml/day, P < 0.001). The increased size of the kallikrein containing cells correlated with kallikrein excretion (r = 0.7013, P < 0.002). These results suggest that high potassium diet stimulates the kallikrein containing cells of the distal nephron producing hyperplasia and hypertrophy. Taken the ultrastructural changes together with the increased urinary excretion of kallikrein, the results suggest that a high potassium diet increased the synthesis and secretion of kallikrein. The nature of this stimulatory effect cannot be elucidated from the present study

Ontogeny of bradykinin B2 receptors in the rat kidney: Implications for segmental nephron maturation

Ontogeny of bradykinin B2 receptors in the rat kidney: Implications for segmental nephron maturation. Kinins modulate renal function, yet their role in the developing kidney is largely unknown. To explore the developmental role of the kallikrein-kinin system, we examined the postnatal ontogeny and intrarenal localization of B2 receptors in the rat. Northern blot analysis and RT-PCR documented the expression of B2 receptor mRNA in the kidney and extrarenal tissues of fetal, neonatal and adult animals. The abundance of B2 receptor mRNA is 10- to 30-fold higher in neonatal than adult tissues in the following order: kidney > heart > aorta > lung > brain. Receptor autoradiography revealed a gradual shift in the localization of bradykinin binding sites from the outer cortex in the newborn to the outer medulla in weanling and maturing rats. The almost complete displacement of [125I]tyr0-bradykinin by HOE-140 indicates that the majority of kinin receptors in the developing kidney belong to the B2 type. Immunolocalization studies using antipeptide antibodies directed against various portions of the receptor revealed that B2 receptors are first expressed on the luminal aspect of the upper limb of S-shaped bodies and differentiating cortical collecting ducts. In marked contrast, the metanephric mesenchyme, pretubular aggregates and glomeruli display weak or no B2 receptor immunoreactivity. Following completion of nephrogenesis, B2 receptor expression shifts to both luminal and basolateral aspects of connecting tubules and collecting ducts. The results demonstrate that bradykinin B2 receptor gene expression is activated in the developing kidney and cardiovascular system. The spatially restricted expression of B2 receptors in the differentiating epithelium of the distal nephron, the site of kinin formation, supports the hypothesis that kinins are paracrine modulators of segmental nephron maturation

CompareML: A Novel Approach to Supporting Preliminary Data Analysis Decision Making

There are a large number of machine learning algorithms as well as a wide range of libraries and services that allow one to create predictive models. With machine learning and artificial intelligence playing a major role in dealing with engineering problems, practising engineers often come to the machine learning field so overwhelmed with the multitude of possibilities that they find themselves needing to address difficulties before actually starting on carrying out any work. Datasets have intrinsic properties that make it hard to select the algorithm that is best suited to some specific objective, and the ever-increasing number of providers together make this selection even harder. These were the reasons underlying the design of CompareML, an approach to supporting the evaluation and comparison of machine learning libraries and services without deep machine learning knowledge. CompareML makes it easy to compare the performance of different models by using well-known classification and regression algorithms already made available by some of the most widely used providers. It facilitates the practical application of methods and techniques of artificial intelligence that let a practising engineer decide whether they might be used to resolve hitherto intractable problems. Thus, researchers and engineering practitioners can uncover the potential of their datasets for the inference of new knowledge by selecting the most appropriate machine learning algorithm and determining the provider best suited to their data

The Crystal Structure of Nitrosomonas Europaea Sucrose Synthase Reveals Critical Conformational Changes and Insights into the Sucrose Metabolism in Prokaryotes

In this paper we report the first crystal structure of a prokaryotic sucrose synthase from the non-photosynthetic bacterium Nitrosomonas europaea. The obtained structure was in an open form, whereas the only other available structure from the plant Arabidopsis thaliana was in a closed conformation. Comparative structural analysis revealed a “hinge-latch” combination, which is critical to transition between the open and closed forms of the enzyme. The N. europaea sucrose synthase shares the same fold as the GT-B family of the retaining glycosyltransferases. In addition, a triad of conserved homologous catalytic residues in the family showed to be functionally critical in the N. europaea sucrose synthase (Arg567, Lys572, Glu663). This implies that sucrose synthase shares not only a common origin with the GT-B family, but also a similar catalytic mechanism. The enzyme preferred transferring glucose from ADP-glucose rather than UDP-glucose like the eukaryotic counterparts. This predicts that these prokaryotic organisms have a different sucrose metabolic scenario from plants. Nucleotide preference determines where the glucose moiety is targeted after sucrose is degraded

Combined quantitative measures of ER, PR, HER2, and KI67 provide more prognostic information than categorical combinations in luminal breast cancer.

Although most women with luminal breast cancer do well on endocrine therapy alone, some will develop fatal recurrence thereby necessitating the need to prospectively determine those for whom additional cytotoxic therapy will be beneficial. Categorical combinations of immunohistochemical measures of ER, PR, HER2, and KI67 are traditionally used to classify patients into luminal A-like and B-like subtypes for chemotherapeutic reasons, but this may lead to the loss of prognostically relevant information. Here, we compared the prognostic value of quantitative measures of these markers, combined in the IHC4-score, to categorical combinations in subtypes. Using image analysis-based scores for all four markers, we computed the IHC4-score for 2498 patients with luminal breast cancer from two European study populations. We defined subtypes (A-like (ER + and PR + : and HER2- and low KI67) and B-like (ER + and/or PR + : and HER2 + or high KI67)) by combining binary categories of these markers. Hazard ratios and 95% confidence intervals for associations with 10-year breast cancer-specific survival were estimated in Cox proportional-hazard models. We accounted for clinical prognostic factors, including grade, tumor size, lymph-nodal involvement, and age, by using the PREDICT-score. Overall, Subtypes [hazard ratio (95% confidence interval) B-like vs. A-like = 1.64 (1.25-2.14); P-value < 0.001] and IHC4-score [hazard ratio (95% confidence interval)/1 standard deviation = 1.32 (1.20-1.44); P-value < 0.001] were prognostic in univariable models. However, IHC4-score [hazard ratio (95% confidence interval)/1 standard deviation = 1.24 (1.11-1.37); P-value < 0.001; likelihood ratio chi-square (LRχ2) = 12.5] provided more prognostic information than Subtype [hazard ratio (95% confidence interval) B-like vs. A-like = 1.38 (1.02-1.88); P-value = 0.04; LRχ2 = 4.3] in multivariable models. Further, higher values of the IHC4-score were associated with worse prognosis, regardless of subtype (P-heterogeneity = 0.97). These findings enhance the value of the IHC4-score as an adjunct to clinical prognostication tools for aiding chemotherapy decision-making in luminal breast cancer patients, irrespective of subtype

Seguimiento de un sistema combinado de tratamiento de líquidos cloacales con un reactor UASB y lagunas de estabilización

Se estudia el comportamiento de un sistema combinado de tratamiento de líquidos cloacales, de escala piloto, compuesto por un reactor UASB y lagunas de estabilización (tratamiento terciario) durante aproximadamente 800 días de operación. Se determinó la remoción de materia orgánica en el sistema y se compara con resultados previos obtenidos con el sistema compuesto por dos reactores UASB – lagunas. La remoción de materia orgánica media en el Reactor UASB fue de aproximadamente 72%, con una concentración de salida promedio de 100,6 mg/L mientras que la remoción total en el Sistema Combinado fue del 73% a lo largo de toda la experiencia. El sistema combinado Reactor UASB- Lagunas es una opción atractiva para el tratamiento de líquidos cloacales en regiones subtropicales.The behavior of an anaerobic- aerobic Combined System for sewage treatment, pilot plant size, was studied for an operating period of nearly 800 days. The system, made up by one UASB reactor and stabilization ponds in series, was compared with another system of two UASB reactors and ponds previously studied, measuring the removal of organic matter (as % of removed COD) of the whole system and its components. In the UASB Reactor the average COD removal was nearly 72% and average COD effluent concentration was 100,0 mg /L, while in the whole Combined System COD removal was 73% during all the operating period. The Combined System UASB Reactor- Stabilization Ponds constitutes an attractive option for sewage treatment in subtropical regions.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Seguimiento de un sistema combinado de tratamiento de líquidos cloacales con un reactor UASB y lagunas de estabilización

Se estudia el comportamiento de un sistema combinado de tratamiento de líquidos cloacales, de escala piloto, compuesto por un reactor UASB y lagunas de estabilización (tratamiento terciario) durante aproximadamente 800 días de operación. Se determinó la remoción de materia orgánica en el sistema y se compara con resultados previos obtenidos con el sistema compuesto por dos reactores UASB – lagunas. La remoción de materia orgánica media en el Reactor UASB fue de aproximadamente 72%, con una concentración de salida promedio de 100,6 mg/L mientras que la remoción total en el Sistema Combinado fue del 73% a lo largo de toda la experiencia. El sistema combinado Reactor UASB- Lagunas es una opción atractiva para el tratamiento de líquidos cloacales en regiones subtropicales.The behavior of an anaerobic- aerobic Combined System for sewage treatment, pilot plant size, was studied for an operating period of nearly 800 days. The system, made up by one UASB reactor and stabilization ponds in series, was compared with another system of two UASB reactors and ponds previously studied, measuring the removal of organic matter (as % of removed COD) of the whole system and its components. In the UASB Reactor the average COD removal was nearly 72% and average COD effluent concentration was 100,0 mg /L, while in the whole Combined System COD removal was 73% during all the operating period. The Combined System UASB Reactor- Stabilization Ponds constitutes an attractive option for sewage treatment in subtropical regions.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Seguimiento de un sistema combinado de tratamiento de líquidos cloacales con un reactor UASB y lagunas de estabilización

Se estudia el comportamiento de un sistema combinado de tratamiento de líquidos cloacales, de escala piloto, compuesto por un reactor UASB y lagunas de estabilización (tratamiento terciario) durante aproximadamente 800 días de operación. Se determinó la remoción de materia orgánica en el sistema y se compara con resultados previos obtenidos con el sistema compuesto por dos reactores UASB – lagunas. La remoción de materia orgánica media en el Reactor UASB fue de aproximadamente 72%, con una concentración de salida promedio de 100,6 mg/L mientras que la remoción total en el Sistema Combinado fue del 73% a lo largo de toda la experiencia. El sistema combinado Reactor UASB- Lagunas es una opción atractiva para el tratamiento de líquidos cloacales en regiones subtropicales.The behavior of an anaerobic- aerobic Combined System for sewage treatment, pilot plant size, was studied for an operating period of nearly 800 days. The system, made up by one UASB reactor and stabilization ponds in series, was compared with another system of two UASB reactors and ponds previously studied, measuring the removal of organic matter (as % of removed COD) of the whole system and its components. In the UASB Reactor the average COD removal was nearly 72% and average COD effluent concentration was 100,0 mg /L, while in the whole Combined System COD removal was 73% during all the operating period. The Combined System UASB Reactor- Stabilization Ponds constitutes an attractive option for sewage treatment in subtropical regions.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES