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Background: Clinical and experimental evidence have shown that renal denervation, by removing both the sympathetic and afferent nerves, improves arterial hypertension and renal function in chronic kidney disease (CKD). Given the key role of renal sympathetic innervation in maintaining sodium and water homeostasis, studies have indicated that the total removal of renal nerves leads to impaired compensatory mechanisms during hemodynamic challenges., Method: In the present study, we hypothesized that afferent (or sensory) fibers from the diseased kidney contribute to sympathetic overactivation to the kidney and other target organ, such as the splanchnic region, contributing to hypertension in CKD. We used a method to remove selectively the afferent renal fibers (periaxonal application of 33 mmol/l capsaicin) in a rat model of CKD, the 5/6 nephrectomy., Results: Three weeks after afferent renal denervation (ARD), we found a decrease in mean arterial pressure (∼15%) and normalization in renal and splanchnic sympathetic nerve hyperactivity in the CKD group. Interestingly, intrarenal renin--angiotensin system, as well as renal fibrosis and function and proteinuria were improved after ARD in CKD rats., Conclusion: The findings demonstrate that afferent fibers contribute to the maintenance of arterial hypertension and reduced renal function that are likely to be mediated by increased sympathetic nerve activity to the renal territory as well as to other target organs in CKD.

The ablation of renal nerves, by destroying both the sympathetic and afferent fibers, has been shown to be effective in lowering blood pressure in resistant hypertensive patients. However, experimental studies have reported that the removal of sympathetic fibers may lead to side effects, such as the impairment of compensatory cardiorenal responses during a hemodynamic challenge. In the present study, we evaluated the effects of the selective removal of renal afferent fibers on arterial hypertension, renal sympathetic nerve activity, and renal changes in a model of renovascular hypertension. After 4 weeks of clipping the left renal artery, afferent renal denervation (ARD) was performed by exposing the left renal nerve to a 33 mM capsaicin solution for 15 min. After 2 weeks of ARD, we found reduced MAP (~ 18%) and sympathoexcitation to both the ischemic and contralateral kidneys in the hypertensive group. Moreover, a reduction in reactive oxygen species was observed in the ischemic (76%) and contralateral (27%) kidneys in the 2K1C group. In addition, ARD normalized renal function markers and proteinuria and podocin in the contralateral kidney. Taken altogether, we show that the selective removal of afferent fibers is an effective method to reduce MAP and improve renal changes without compromising the function of renal sympathetic fibers in the 2K1C model. Renal afferent nerves may be a new target in neurogenic hypertension and renal dysfunction.

The underlying mechanisms by which renal denervation (RD) decreases blood pressure (BP) remain incompletely understood. In this study, we investigated the effects of ischemic kidney denervation on different sympathetic outflows, brain and renal expression of angiotensin-II receptors, oxidative stress and renal function markers in the 2-kidney, 1-clip (2K-1C) rat model. Surgical RD was performed in Wistar male rats 4-5 weeks after clip implantation. After 10 days of RD, BP, and the activity of sympathetic nerves projecting to the contralateral kidney (rSNA) and splanchnic region were partially reduced in 2K-1C rats, with no change in systemic renin-angiotensin system (RAS). To distinguish the effects of RD from the reduction in BP, 2K-1C rats were treated with hydralazine by oral gavage (25 mg/kg/day for 1 week). RD, but not hydralazine, normalized oxidative stress in the sympathetic premotor brain regions and improved intrarenal RAS, renal injury, and proteinuria. Furthermore, different mechanisms led to renal injury and oxidative stress in the ischemic and contralateral kidneys of 2K-1C rats. Injury and oxidative stress in the ischemic kidney were driven by the renal nerves. Although RD attenuated rSNA, injury and oxidative stress persisted in the contralateral kidney, probably due to increased BP. Therefore, nerves from the ischemic kidney at least partially contribute to the increase in BP, sympathetic outflows, brain oxidative stress, and renal alterations in rats with renovascular hypertension. Based on these findings, the reduction in oxidative stress in the brain is a central mechanism that contributes to the effects of RD on Goldblatt hypertension.

Introduction: Stereotactic radiosurgery (SRS) is increasingly used as a minimally invasive alternative in many neurosurgical conditions, including benign and malignant tumors, vascular malformations, and functional procedures. As for any surgical procedure, strict safety guidelines and checklists are necessary to avoid errors and the inherent unnecessary complications. With regard to the former, other groups have already reported human and/or technical errors. We describe our safety checklist for Gamma Knife radiosurgical procedures., Methods: We describe our checklist protocol after an experience gained over 1500 radiosurgical procedures, using Gamma Knife radiosurgery, performed over a period of 8 years, while employing the same list of items. Minor implementation has been performed over time to address some safety issues that could be improved., Results: Two types of checklist are displayed. One is related to the indications when a specific tissue volume is irradiated, including tumors or vascular disorders. The second corresponds to functional disorders, such as when the dose is prescribed to one specific point. Using these checklists, no human error had been reported during the past 8 years of practice in our institution., Conclusion: The use of a safety checklist for SRS procedures promotes a zero-tolerance attitude for errors. This can lower the complications and is of major help in promoting multidisciplinary cooperation. We highly recommend the use of such tool, especially in the context of the increased use of SRS in the neurosurgical field.

Presympathetic neurons in the rostral ventrolateral medulla (RVLM) including the adrenergic cell groups play a major role in the modulation of several reflexes required for the control of sympathetic vasomotor tone and blood pressure (BP). Moreover, sympathetic vasomotor drive to the kidneys influence natriuresis and diuresis by inhibiting the cAMP/PKA pathway and redistributing the Na + /H + exchanger isoform 3 (NHE3) to the body of the microvilli in the proximal tubules. In this study we aimed to evaluate the effects of renal afferents stimulation on (1) the neurochemical phenotype of Fos expressing neurons in the medulla oblongata and (2) the level of abundance and phosphorylation of NHE3 in the renal cortex. We found that electrical stimulation of renal afferents increased heart rate and BP transiently and caused activation of tyrosine hydroxylase (TH)-containing neurons in the RVLM and non-TH neurons in the NTS. Additionally, activation of the inhibitory renorenal reflex over a 30-min period resulted in increased natriuresis and diuresis associated with increased phosphorylation of NHE3 at serine 552, a surrogate for reduced activity of this exchanger, in the contralateral kidney. This effect was not dependent of BP changes considering that no effects on natriuresis or diuresis were found in the ipsilateral-stimulated kidney. Therefore, our data show that renal afferents leads to activation of catecholaminergic and non-catecholaminergic neurons in the medulla oblongata. When renorenal reflex is induced, NHE3 exchanger activity appears to be decreased, resulting in decreased sodium and water reabsorption in the contralateral kidney., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Caring for young infants can be stressful. Non-accidental brain or head injury (shaken baby syndrome) is a result of parental stress, and a lack of knowledge of how to respond to a crying infant and the dangers of shaking a child. This article demonstrates the value of international collaboration in projects to prevent child maltreatment. It includes reports of prevention of shaken baby syndrome programmes in Australia, Hungary, Greece, Brazil and Turkey.

Objective: To review the scientific literature on pediatric abusive head trauma as a form of physical abuse against infants and young children, highlighting the prevalence, signs and symptoms, consequences, risk factors for its occurrence, and prevention strategies., Data Source: The MEDLINE, SciELO, LILACS, and Web of Science databases from 2001 to 2012 were reviewed, using the terms "shaken baby syndrome" and "abusive head trauma" in English, Spanish, and Portuguese., Data Synthesis: Pediatric abusive head trauma is defined as injury to the skull or intracranial contents of a infant or child younger than 5 years due to intentional abrupt impact and/or violent shaking. It occurs mainly in infants and children under 1 year of age, and may result in severe consequences, from physical or mental disabilities to death. Although there are specific signs for this form of abuse, they can be mistaken for common illnesses in children or accidental head injury; thus, clinical training of professionals involved in the assessment of cases to attain the correct diagnosis is crucial. Prevention strategies should include early identification of cases, as well as parental education on child development, especially on the infant's crying pattern., Conclusions: Considering the severity of abusive head trauma in children, it is critical that prevention strategies be implemented and evaluated in the Brazilian context. It is suggested that its incidence indicators be assessed at the national level., (Copyright © 2013 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)

We assessed the quality of hand hygiene among healthcare workers at a pediatrics hospital in Rio de Janeiro, Brazil. Hand hygiene was performed in 491 (34%) of 1,455 opportunities. Of these hand hygiene events, correct performance was observed in only 173 (35%). Multivariate analysis revealed that correct performance of hand hygiene was associated with the use of an alcohol-based product and a lack of jewelry (for all events) and employment in an infirmary with a comparatively higher ratio of nurses to patients (for events involving nurses).