Current Use and Complementary Value of Combining in Vivo Imaging Modalities to Understand the Renoprotective Effects of Sodium-Glucose Cotransporter-2 Inhibitors at a Tissue Level.

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) were initially developed to treat diabetes and have been shown to improve renal and cardiovascular outcomes in patients with- but also without diabetes. The mechanisms underlying these beneficial effects are incompletely understood, as is the response variability between- and within patients. Imaging modalities allow in vivo quantitative assessment of physiological, pathophysiological, and pharmacological processes at kidney tissue level and are therefore increasingly being used in nephrology. They provide unique insights into the renoprotective effects of SGLT2i and the variability in response and may thus contribute to improved treatment of the individual patient. In this mini-review, we highlight current work and opportunities of renal imaging modalities to assess renal oxygenation and hypoxia, fibrosis as well as interaction between SGLT2i and their transporters. Although every modality allows quantitative assessment of particular parameters of interest, we conclude that especially the complementary value of combining imaging modalities in a single clinical trial aids in an integrated understanding of the pharmacology of SGLT2i and their response variability.

Estudo dos efeitos desencadeados pelo veneno de Bothrops moojeni na síntese de mediadores inflamatórios em pré- adipócitos e os mecanismos envolvidos

Snakebites constitute an important public health problem, recognized by World Health Organization. In Brazil, Bothrops genus snakes are responsible for the major number of registered envenomation cases. Among this genus, the species B. moojeni is known for the severity of local inflammatory response. However, systemic repercussions of bothropic envenomation are still not well stablished. In this context, adipose tissue is a metabolically active organ, known for producing many proinflammatory mediators. Preadipocytes and adipocytes are important cell types that constitute this tissue and possess the capacity of synthetize components that drive to inflammation. Therefore, this study aims to investigate the effects of B. moojeni whole venom (BmV), in cultured preadipocytes, with focus on: i) release of cytokines and chemokines (TNF-α, IL-6, IL-10, MCP-1 and KC); ii) release of prostaglandin E2 (PGE2); iii) protein expression of cyclooxygenase-1 and -2 (COX-1 and -2); iv) participation of COX-1, -2, and PGE2 receptors (EP1-4) on PGE2 release; v) activation of transcription factor NF-κB; vi) participation of NF-κB on PGE2 release and COX-2 protein expression; and vii) preadipocytes differentiation into mature adipocytes. Moreover, the venom effects in adipocytes were investigated, focusing on: i) PGE2 release and ii) COX-2 protein expression. In order to this, 3T3-L1 preadipocytes were cultured in DMEM medium, with 10% BFS, 1% L-glutamine and antibiotics until confluence. Next, they were incubated with DMEM only, or TNF-α (20 ng/mL), or BmV (1 μg/mL) for different experimental periods of time. TNF-α, IL-6, IL- 10, MCP-1, KC and PGE2 concentration, in supernatants, was evaluated by ELISA. COX-1, -2, and P-NF-κB protein expression was determined by Western blotting analysis. COX-1, -2, EP1-4 receptors and NF-κB participation on PGE2 release were evaluated utilizing pharmacological treatments with specific inhibitors and/or antagonists. BmV effect on preadipocytes differentiation into mature adipocytes was evaluated according to protocol previously described in literature. Taken together, results obtained show that BmV activates proinflammatory pathways in preadipocytes and mature adipocytes. This venom acts on these cells stimulating the synthesis of cytokines that regulate inflammation (IL-6 and IL-10), or that possess chemotactic activity (KC), besides PGE2. Moreover, BmV was capable of activating mature adipocytes to PGE2 synthesis. In preadipocytes, COX-1 and -2 and EP1 receptor are important factors of venom-induced mechanisms involved in PGE2 release, with COX-2 protein expression increased in this process. It was also demonstrated NF-κB participation in PGE2 synthesis by preadipocytes. Finally, BmV is able to enhance preadipocytes differentiation into mature adipocytes. Taken together, this work indicates that adipose tissue cells are targets for BmV and must collaborate to the biosynthesis of inflammatory mediators involved in bothropic envenoming pathophysiology.

Os acidentes ofídicos constituem um importante problema de saúde pública, reconhecido pela Organização Mundial da Saúde. No Brasil, as serpentes do gênero Bothrops são responsáveis pelo maior número de envenenamentos registrados. Dentro deste gênero, a espécie B. moojeni é conhecida pela gravidade da resposta inflamatória exacerbada, no local da picada. No entanto, as repercussões sistêmicas do envenenamento botrópico, em diferentes tecidos, ainda não são bem estabelecidas. Neste contexto, o tecido adiposo é um órgão metabolicamente ativo, conhecido por produzir diversos mediadores pró-inflamatórios. Os pré-adipócitos e adipócitos são importantes tipos celulares que constituem este tecido e possuem a capacidade de sintetizar componentes que conduzem à inflamação. Sendo assim, o objetivo do presente estudo foi investigar os efeitos do veneno bruto de B. moojeni (VBm), em pré-adipócitos, em cultura, quanto a: i) liberação de citocinas e quimiocinas (TNF-α, IL-6, IL-10, MCP-1 e KC); ii) liberação de prostaglandina E2 (PGE2); iii) expressão proteica de ciclo-oxigenases-1 e -2 (COX-1 e -2); iv) participação das COX-1 e -2, e dos receptores de PGE2 (EP1-4) na liberação de PGE2; v) ativação do fator de transcrição NF-κB; vi) participação do NF-κB na liberação de PGE2 e na expressão proteica de COX-2; e vii) diferenciação de pré- adipócitos em adipócitos maduros. Ainda, o efeito do veneno em adipócitos foi investigado quando à: i) liberação de PGE2 e ii) expressão proteica de COX-2. Pré- adipócitos da linhagem 3T3-L1 foram cultivados em meio DMEM, contendo 10% de SFB, 1% de L-glutamina e antibiótico até a confluência. Em seguida, foram incubados com apenas DMEM, ou TNF-α (20 ng/mL), ou VBm (1 μg/mL) por diferentes períodos de tempo experimentais. A concentração de TNF-α, IL-6, IL-10, MCP-1 e KC, nos sobrenadantes, foi avaliada por ELISA. A expressão proteica de COX-1 e -2 e P-NF-κB foi determinada por Western blotting. A participação das COX-1 e -2, dos receptores EP1-4 e do NF-κB na liberação de PGE2 foi avaliada utilizando-se inibidores e/ou antagonistas específicos. O efeito do VBm na diferenciação de pré-adipócitos em adipócitos maduros foi avaliada seguindo protocolo descrito na literatura. Em conjunto, os resultados obtidos evidenciaram que o VBm ativa vias pró-inflamatórias em pré-adipócitos e adipócitos maduros. Este veneno atua sobre estas células estimulando a síntese de citocinas, que regulam a inflamação (IL-6 e IL-10), ou possuem atividade quimiotáxica (KC), além de PGE2. Além disso, o VBm foi capaz de ativar adipócitos maduros para a síntese de PGE2. Em pré-adipócitos, as COX-1 e -2 e o receptor EP1 são fatores importantes nos mecanismos desencadeados pelo veneno, que acarretam a liberação de PGE2, sendo que a COX-2 tem sua expressão proteica aumentada neste processo. Também foi demonstrada a participação do NF-κB na síntese de PGE2 em pré- adipócitos. Por fim, o VBm é capaz de aumentar a diferenciação de PAds em adipócitos maduros, provavelmente através dos mecanismos antilipolíticos da PGE2. Em conclusão, este trabalho aponta que as células do tecido adiposo são alvos do VBm e devem colaborar para a biossíntese de mediadores inflamatórios, envolvidos na fisiopatologia do envenenamento botrópico.

Pathophysiological Role of Synovitis in Hemophilic Arthropathy Development: A Two-Hit Hypothesis.

Despite an increasing access to prophylaxis with clotting factor concentrates, arthropathy still represents the main chronic complication of hemophilia. Whereas previous studies described hemophilic arthropathy (HA) as a degenerative arthropathy, somehow resembling osteoarthritis (OA), most recent evidence suggests that complex inflammatory and immunologic mechanisms are also involved in the pathophysiology of HA. In the present review, we described available data on major mechanisms leading to arthropathic changes in patients with hemophilia, with a specific focus on the role of synovium. The presence of hemosiderin in the joint space induces synovium proliferation, thus leading to formation of several lytic enzymes determining chondrocytes apoptosis and proteoglycans levels reduction. This leads to a direct joint "chemical" damage representing early damages in the pathogenesis of HA (first hit). In parallel, synovial membrane and synovial endothelial cells become a dynamic reservoir of inflammatory cells and mediators, and propagate the inflammatory response (second hit), switching the process from a chemical damage to an inflammatory damage. Overall, consistent data pointed out synovitis as the keystone in HA pathophysiology. This opens novel potential therapeutic targets in this clinical setting.

Should We Use Clinical Tools to Identify Disease Progression?

The presence of disability progression in multiple sclerosis (MS) is an important hallmark for MS patients in the course of their disease. The transition from relapsing remitting (RRMS) to secondary progressive forms of the disease (SPMS) represents a significant change in their quality of life and perception of the disease. It could also be a therapeutic key for opportunities, where approaches different from those in the initial phases of the disease can be adopted. The characterization of structural biomarkers (e.g., magnetic resonance imaging or neurofilament light chain) has been proposed to differentiate between both phenotypes. However, there is no definite threshold between them. Whether the risk of clinical progression can be predicted by structural markers at early disease phases is still a focus of clinical research. However, several theories and pathological evidence suggest that both disease phenotypes are part of a continuum with common pathophysiological mechanisms. In this case, the clinical evaluation of the patients would play a preponderant role above destruction biomarkers for the early identification of disability progression and SPMS. For this purpose, the use of clinical tools beyond the Expanded Disability Status Scale (EDSS) should be considered. Besides established functional tests such as the Multiple Sclerosis Functional Composite (MSFC), patient's neurological history or digital resources may help neurologists in the decision-taking. In this article, we discuss arguments for the use of clinical markers in the detection of secondary progressive MS and the characterization of progressive disease activity.

A New Look at the Structures of Old Sepsis Actors by Exploratory Data Analysis Tools.

Sepsis is a life-threatening condition that accounts for numerous deaths worldwide, usually complications of common community infections (i.e., pneumonia, etc), or infections acquired during the hospital stay. Sepsis and septic shock, its most severe evolution, involve the whole organism, recruiting and producing a lot of molecules, mostly proteins. Proteins are dynamic entities, and a large number of techniques and studies have been devoted to elucidating the relationship between the conformations adopted by proteins and what is their function. Although molecular dynamics has a key role in understanding these relationships, the number of protein structures available in the databases is so high that it is currently possible to build data sets obtained from experimentally determined structures. Techniques for dimensionality reduction and clustering can be applied in exploratory data analysis in order to obtain information on the function of these molecules, and this may be very useful in immunology to better understand the structure-activity relationship of the numerous proteins involved in host defense, moreover in septic patients. The large number of degrees of freedom that characterize the biomolecules requires special techniques which are able to analyze this kind of data sets (with a small number of entries respect to the number of degrees of freedom). In this work we analyzed the ability of two different types of algorithms to provide information on the structures present in three data sets built using the experimental structures of allosteric proteins involved in sepsis. The results obtained by means of a principal component analysis algorithm and those obtained by a random projection algorithm are largely comparable, proving the effectiveness of random projection methods in structural bioinformatics. The usefulness of random projection in exploratory data analysis is discussed, including validation of the obtained clusters. We have chosen these proteins because of their involvement in sepsis and septic shock, aimed to highlight the potentiality of bioinformatics to point out new diagnostic and prognostic tools for the patients.

Educational reform centered on independent study / 中华医学教育探索杂志

Reform was made on traditional education mode based on the criterion of undergraduate medical education at home and aboard.The reform includes the changes in teaching content,teaching methods and assessment methods in an aim to establish independent learning mode,cultivate students' self-study ability,initiative spirit and innovation ability.

Endolymphatic Hydrops: Pathophysiology and Etiology / 대한이비인후과학회지

Endolymphatic hydrops (EH) represents a histopathologic finding in which the structures bounding the endolymphatic space are distended by an enlargement of endolymphatic volume. EH primarily involves the cochlear duct and saccule but can involve the utricle and ampullae of the semicircular canals. EH is a consistent finding in patients with Meniere's disease, however, the reverse is not true. EH may occur as a consequence of a variety of disorders, including DFNA 9, Alport syndrome, serous labyrinthitis, suppurative labyrinthitis, otosyphilis, temporal bone fracture, surgical trauma, neoplasm, immune disorders, otosclerosis, or Paget's disease. The mechanism of development of hydrops is also unclear. This review provides information to understand the recent pathophysiologic mechanism and causal disoders in EH.

Phospholipase A2 changes and its significance on brain tissue of rat in severe acute pancreatitis / 药物分析学报

Objective To survey changes and the significance of phospholipase A2(PLA2) on brain tissue of SD rat in acute pancreatitis. Methods With retrograde injection of 3% taurocholate sodium into pancreatic and biliary duct, rat model of severe acute pancreatitis (SAP) was made,and it included four groups: the control group, the sham-operation group, the SAP group and the PLA2 inhibitor-treated group of SAP. Serum amylases, PLA2 and PLA2 in brain tissue were measured and the brain tissue changes were observed. Results There were no significant difference in serum amylases, PLA2 and PLA2 in brain tissue between the sham-operation and the control groups; the levels of serum amylases, PLA2 and PLA2 in brain tissue in the SAP group were higher than those in the control. In the SAP group expansion and hemorrhage of meninges, intracephalic arteriolar hyperemia, in meninges and cephalic-parenchyma infiltration of inflammatory cells and interval broaden were observed, significant differences were found between two groups.Compared with the SAP group, the level of serum amylase, PLA2 and PLA2 in brain tissue were reduced significantly in the treatment group of SAP. Pathological damages in the treatment group were significantly reduced when compared with the SAP group. Conclusion PLA2 might play an important role in brain tissue damages in severe acute pancreatitis.