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Context: Aldosterone-producing adenomas (APAs) are a common cause of primary aldosteronism (PA). Despite the discovery of somatic mutations in APA and the characterization of multiple factors regulating adrenal differentiation and function, the sequence of events leading to APA formation remains to be determined. Objective: We investigated the role of Wnt/β-catenin and adrenocorticotropin signaling, as well as elements of paracrine regulation of aldosterone biosynthesis in adrenals with APA and their relationship to intratumoral heterogeneity and mutational status. Methods: We analyzed the expression of aldosterone-synthase (CYP11B2), CYP17A1, β-catenin, melanocortin type 2 receptor (MC2R), phosphorlyated cAMP response element-binding protein (pCREB), tryptase, S100, CD34 by multiplex immunofluorescence, and immunohistochemistry-guided reverse transcription–quantitative polymerase chain reaction. Eleven adrenals with APA and 1 with micronodular hyperplasia from patients with PA were analyzed. Main outcome measures included localization of CYP11B2, CYP17A1, β-catenin, MC2R, pCREB, tryptase, S100, CD34 in APA and aldosterone-producing cell clusters (APCCs). Results: Immunofluorescence revealed abundant mast cells and a dense vascular network in APA, independent of mutational status. Within APA, mast cells were localized in areas expressing CYP11B2 and were rarely colocalized with nerve fibers, suggesting that their degranulation is not controlled by innervation. In these same areas, ß-catenin was activated, suggesting a zona glomerulosa cell identity. In heterogeneous APA with KCNJ5 mutations, MC2R and vascular endothelial growth factor A expression was higher in areas expressing CYP11B2. A similar pattern was observed in APCC, with high expression of CYP11B2, activated β-catenin, and numerous mast cells. Conclusion: Our results suggest that aldosterone-producing structures in adrenals with APA share common molecular characteristics and cellular environment, despite different mutation status, suggesting common developmental mechanisms. [ABSTRACT FROM AUTHOR]

Fibres and vessels represent the largest proportion of anatomical elements in hardwood tree species. They exert significant effects on various properties of the wood, which, consequently, have several implications for the use of the wood. However, the effect of these elements on wood combustion behaviour is still poorly analysed in the literature. The present study aimed to evaluate the effect of fibre and vessel biometry on wood combustibility. The length, width and cell wall thickness of fibre, diameter of the lumen, and length and width of vessels were measured from five native Miombo tree species in Mozambique, namely Brachystegia boehmii Taub., Brachystegia spiciformis Benth., Julbernardia globiflora (Benth.) Troupin, Parinari curatellifolia Planch. ex Benth. and Uapaca kirkiana Müll. Arg. The fibre quality index and cell wall thickness were determined based on fibre biometry. The flexibility coefficient and the wall fraction are inversely proportional indices and individually affected most of the combustion parameters. Wood ignition is driven by large lumen diameter and flexibility in fibres. In addition, cell wall thickness and a larger wall fraction increase wood combustion. [ABSTRACT FROM AUTHOR]

Objective: Primary aldosteronism (PA) is the most common form of secondar y and curable hypertension. Different germline and somatic mutations are found in aldosterone-produci ng adenoma (APA) and familial forms of the disease, while the causes of bilateral adrenal hyperplasia (BAH) remain largely unknown. Adrenalectomy is the recommended treatment for patients with APA; however, 6% of patients are no t cured and show persistent PA after surgery suggesting BAH. The objective of this study was to analyze clin ical data of patients with APA without biochemical success after adrenalectomy as well as the histological and gen etic characteristics of their adrenal glands. Design and methods: Clinical data of 12 patients with partial and absent biochemic al cure were compared to those from 39 PA patients with hormonal cure after surgery. Histologi cal, morphological, and genetic characterization of the adrenals was carried out by CYP11B2 and CYP11B1 immunostaining and by CYP11B2-guided NGS. Results: Patients with absent hormonal cure displayed a longer duration of arterial hypertension and lower lateralization index of aldosterone production. In ten patients, APAs expressing CYP11B2 were identified. No difference in histological and morphological characteristics was observed between patients with or without a hormonal cure. Somatic mutations in APA driver genes were identified in all CYP 11B2 positive APAs; CACNA1D mutations were the most frequent genetic abnormality. Conclusions: Patients with partial and absent biochemical cure were diagnos ed later and exhibited a lower lateralization index of aldosterone production, suggesting asymmetric aldosterone production in the context of BAH. Somatic mutations in adrenal glands from those patients indicat e common mechanisms underlying BAH and APA. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Primary aldosteronism (PA) is the most common form and an under-diagnosed cause of secondary arterial hypertension, accounting for up to 10% of hypertensive cases and associated to increased cardiovascular risk. PA is caused by autonomous overproduction of aldosterone by the adrenal cortex. It is mainly caused by a unilateral aldosteroneproducing adenoma (APA) or bilateral adrenal hyperplasia. Excess aldosterone leads to arterial hypertension with suppressed renin, frequently associated to hypokalemia. Mutations in genes coding for ion channels and ATPases have bee n identified in APA, explaining the pathophysiology of increased aldosterone production. Different inherited genetic abnormalities led to the distinction of four forms of familial hyperaldosteronism (type I to IV) and other genetic defects very likely remain to be identified. Somatic mutations are identified in APA, but also in aldosterone-produci ng cell clusters (APCCs) in normal adrenals, in image-negative unilateral hyperplasia, in transitional lesions and in APCC from adrenals with bilateral adrenal hyperplasia (BAH). Whether these structures are precursors of APA or whether somatic mutations occur in a proliferative adrenal cortex, is still a matter of debate. This review will summarize our knowledge on the molecular mechanisms responsible for PA and the recent discovery of new genes related to early-onset and familial forms of the disease. We will also address new issues concerning genomic and proteomic changes in adrenals with APA and discuss adrenal pathophysiology in relation to aldosterone-producing structures in the adrenal cortex. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this study was to determine the thermodynamic properties of the process of water sorption in forage turnip seeds. The equilibrium moisture content of forage turnip seeds was determined by the gravimetric-dynamic method for different values of temperature and water activity. According to the results, increasing the moisture content increases the energy required for the evaporation of water in forage turnip seeds, and the values of integral isosteric heat of desorption, within the moisture content range of 3.33 to 11.30 (% d.b.), varies from 4,222.70 to 2,870.34 kJ kg-1. With the elevation in the equilibrium moisture content, there is an increase in differential entropy and Gibbs free energy, which has positive values, demonstrating non-spontaneity in the process of desorption in the seeds. The theory of enthalpy-entropy compensation can be satisfactorily applied to the sorption phenomenon, and the process of water desorption of forage turnip seeds is controlled by enthalpy. [ABSTRACT FROM AUTHOR]