The U-shaped association between serum osmolality and 28-day mortality in patients with sepsis: a retrospective cohort study

BACKGROUND

Sepsis is a recognized global health challenge that places a considerable disease burden on countries. Although there has been some progress in the study of sepsis, the mortality rate of sepsis remains high. The relationship between serum osmolality and the prognosis of patients with sepsis is unclear.

METHOD

Patients with sepsis who met the criteria in the Medical Information Mart for Intensive Care IV database were included in the study. Hazard ratios (HRs) and 95% confidence intervals (CIs) were determined using multivariable Cox regression. The relationship between serum osmolality and the 28-day mortality risk in patients with sepsis was investigated using curve fitting, and inflection points were calculated.

RESULTS

A total of 13,219 patients with sepsis were enrolled in the study; the mean age was 65.1 years, 56.9 % were male, and the 28-day mortality rate was 18.8 %. After adjusting for covariates, the risk of 28-day mortality was elevated by 99% (HR 1.99, 95%CI 1.74-2.28) in the highest quintile of serum osmolality (Q5 >303.21) and by 59% (HR 1.59, 95%CI 1.39-1.83) in the lowest quintile (Q1 ≤285.80), as compared to the reference quintile (Q3 291.38-296.29). The results of the curve fitting showed a U-shaped relationship between serum osmolality and the risk of 28-day mortality, with an inflection point of 286.9 mmol/L.

CONCLUSION

There is a U-shaped relationship between serum osmolality and the 28-day mortality risk in patients with sepsis. Higher or lower serum osmolality is associated with an increased risk of mortality in patients with sepsis. Patients with sepsis have a lower risk of mortality when their osmolality is 285.80-296.29 mmol/L.

Pelvic Floor Physical Therapy for Pelvic Floor Hypertonicity: A Systematic Review of Treatment Efficacy

INTRODUCTION

Hypertonicity of the pelvic floor (PFH) is a disabling condition with urological, gynecological and gastrointestinal symptoms, sexual problems and chronic pelvic pain, impacting quality of life. Pelvic floor physical therapy (PFPT) is a first-line intervention, yet no systematic review on the efficacy of PFPT for the treatment of PFH has been conducted.

OBJECTIVES

To systematically appraise the current literature on efficacy of PFPT modalities related to PFH.

METHODS

PubMed, Embase, Emcare, Web of Science, and Cochrane databases were searched from inception until February 2020. A manual search from reference lists of included articles was performed. Ongoing trials were reviewed using clinicaltrial.gov. Randomized controlled trials (RCTs), prospective - and retrospective cohorts and case-study analyses were included. Outcome measures were pelvic floor muscle tone and function, pain reports, sexual function, pelvic floor symptom scores, quality of life and patients' perceived effect.

RESULTS

The literature search resulted in 10 eligible studies including 4 RCTs, 5 prospective studies, and 1 case study published between 2000 and 2019. Most studies had a high risk of bias associated with the lack of a comparison group, insufficient sample sizes and non-standardized interventions. Six studies were of low and 4 of medium quality. All studies were narratively reviewed. Three of 4 RCTs found positive effects of PFPT compared to controls on five out of 6 outcome measures. The prospective studies found significant improvements in all outcome measures that were assessed. PFPT seems to be efficacious in patients with chronic prostatitis, chronic pelvic pain syndrome, vulvodynia, and dyspareunia. Smallest effects were seen in patients with interstitial cystitis and painful bladder syndrome.

CONCLUSION

The findings of this systematic review suggest that PFPT can be beneficial in patients with PFH. Further high-quality RCTs should be performed to confirm the effectiveness of PFPT in the treatment of PFH. van Reijn-Baggen DA, Han-Geurts IJM, Voorham-van der Zalm PJ, et al. Pelvic Floor Physical Therapy for Pelvic Floor Hypertonicity: A Systematic Review of Treatment Efficacy. Sex Med Rev 2021;XX:1-22.

Influence of Suboptimal Hydration on the Immune Response

BACKGROUND

A healthy immune system is a subtle orchestration of the innate and adaptive immune systems that efficiently detect and process foreign antigens while tolerating the self. The influence of hypertonicity on the immune system is poorly understood [1-16].

SUMMARY

In vitro studies suggest that hypertonicity influences innate and adaptive immunity on several cellular and molecular levels. This influence tends to be pro-inflammatory, but not always. Other cofactors include the duration of exposure to hypertonicity (chronic versus acute), the location in the body, and the timing with priming of the immune system. Recent publications about high salt diet in vitro and in animal models of multiple sclerosis (MS) suggest an influence on the TH17 autoimmune pathway, that does not translate into the human disease in vivo. Key Messages: The influence of hypertonicity on the immune system is complex and depends on multiple factors, such as temporality with immune priming and length of exposure. Since findings in animal models did not always translate into human diseases, further studies are needed to specify the consequences of acute or chronic hypertonicity in healthy subjects or patients with autoimmune diseases such as MS. Further studies need to be conducted in animal models and in humans to better understand the influence of suboptimal hydration on the immune system and on autoimmune diseases, and address its clinical relevance.

Hypotheses about sub-optimal hydration in the weeks before coronavirus disease (COVID-19) as a risk factor for dying from COVID-19

To address urgent need for strategies to limit mortality from coronavirus disease 2019 (COVID-19), this review describes experimental, clinical and epidemiological evidence that suggests that chronic sub-optimal hydration in the weeks before infection might increase risk of COVID-19 mortality in multiple ways. Sub-optimal hydration is associated with key risk factors for COVID-19 mortality, including older age, male sex, race-ethnicity and chronic disease. Chronic hypertonicity, total body water deficit and/or hypovolemia cause multiple intracellular and/or physiologic adaptations that preferentially retain body water and favor positive total body water balance when challenged by infection. Via effects on serum/glucocorticoid-regulated kinase 1 (SGK1) signaling, aldosterone, tumor necrosis factor-alpha (TNF-alpha), vascular endothelial growth factor (VEGF), aquaporin 5 (AQP5) and/or Na⁺/K⁺-ATPase, chronic sub-optimal hydration in the weeks before exposure to COVID-19 may conceivably result in: greater abundance of angiotensin converting enzyme 2 (ACE2) receptors in the lung, which increases likelihood of COVID-19 infection, lung epithelial cells which are pre-set for exaggerated immune response, increased capacity for capillary leakage of fluid into the airway space, and/or reduced capacity for both passive and active transport of fluid out of the airways. The hypothesized hydration effects suggest hypotheses regarding strategies for COVID-19 risk reduction, such as public health recommendations to increase intake of drinking water, hydration screening alongside COVID-19 testing, and treatment tailored to the pre-infection hydration condition. Hydration may link risk factors and pathways in a unified mechanism for COVID-19 mortality. Attention to hydration holds potential to reduce COVID-19 mortality and disparities via at least 5 pathways simultaneously.

The effects of serial casting on lower limb function for children with Cerebral Palsy: a systematic review with meta-analysis

Background

Lower limb serial casting is commonly used therapeutically in paediatric clinical practice with some evidence to support its efficacy. This systematic review aimed to determine the effects of serial casting in isolation or combination with other therapies for the management of lower limb dysfunction in children with Cerebral Palsy (CP).

Methods

A systematic literature search was conducted in February 2019 across eight databases (PUBMED, EMBASE, CINAHL, PEDro, OTSeeker, Cochrane, Scopus and Proquest) using key terms ‘Cerebral Palsy’ and ‘serial casting’ and associated synonyms. A meta-synthesis and meta-analysis were undertaken when sufficient results were available showing the effect of serial casting on functional outcomes including: Ankle range of motion; neurological measures of hypertonicity and spasticity, functional gait measures and; gross motor function.

Results

Twenty-five articles from 3219 possible citations were included. Serial casting was found to be effective for: Improving ankle dorsiflexion (DF) passive range of motion (PROM) in the immediate to short-term, decreasing hypertonicity measured by Modified Ashworth Scale (MAS) in the short-term and, enhancing functional gait outcomes in the mid-term. Serial casting with or without botulinum toxin type-A (BTX-A) did not significantly affect gross motor capacity measured by Gross Motor Function Measure (GMFM). Serial casting with pharmacological intervention achieved significantly more DF PROM than serial casting alone (MD − 3.19 degrees; 95% CI − 5.76 to − 0.62; P = 0.01; I² = 0%), however the clinical importance of improving ankle DF PROM by an additional three degrees remains unclear.

Conclusions

Lower limb serial casting, improves several outcomes relevant to lower limb function supporting its clinical use for improving DF PROM, reducing hypertonicity and improving gait in children with CP. Further research using stronger methodological study designs, is indicated to explore long-term effects of serial casting on functional lower limb outcomes such as gross motor function in children with CP. Clinicians can use this information when developing individualised treatment plans for children who have CP during shared decision-making consultations.

Dialysis-associated hyperglycemia: manifestations and treatment

PURPOSE

Dialysis-associated hyperglycemia (DAH), is associated with a distinct fluid and electrolyte pathophysiology. The purpose of this report was to review the pathophysiology and provide treatment guidelines for DAH.

METHODS

Review of published reports on DAH. Synthesis of guidelines based on these reports.

RESULTS

The following fluid and solute abnormalities have been identified in DAH: (a) hypoglycemia: this is a frequent complication of insulin treatment and its prevention requires special attention. (b) Elevated serum tonicity. The degree of hypertonicity in DAH is lower than in similar levels of hyperglycemia in patients with preserved renal function. Typically, correction of hyperglycemia with insulin corrects the hypertonicity of DAH. (c) Extracellular volume abnormalities ranging from pulmonary edema associated with osmotic fluid shift from the intracellular into the extracellular compartment as a consequence of gain in extracellular solute (glucose) to hypovolemia from osmotic diuresis in patients with residual renal function or from fluid losses through extrarenal routes. Correction of DAH by insulin infusion reverses the osmotic fluid transfer between the intracellular and extracellular compartments and corrects the pulmonary edema, but can worsen the manifestations of hypovolemia, which require saline infusion. (d) A variety of acid-base disorders including ketoacidosis correctable with insulin infusion and no other interventions. (e) Hyperkalemia, which is frequent in DAH and is more severe when ketoacidosis is also present. Insulin infusion corrects the hyperkalemia. Extreme hyperkalemia at presentation or hypokalemia developing during insulin infusion require additional measures.

CONCLUSIONS

In DAH, insulin infusion is the primary management strategy and corrects the fluid and electrolyte abnormalities. Patients treated for DAH should be monitored for the development of hypoglycemia or fluid and electrolyte abnormalities that may require additional treatments.

Hypertonicity primes malignant melanoma cells for apoptosis

The tumor environment critically influences responsiveness of cancer cells to chemotherapies, most of which activate the mitochondria-regulated (intrinsic) apoptotic cascade to kill malignant cells. Especially skin tumors encounter an environment with remarkable biophysical properties. Cutaneous accumulation of Na⁺ locally establishes osmotic pressure gradients in vivo (hypertonicity or hyperosmotic stress), but whether cutaneous hypertonicity is a factor that modulates the responsiveness of skin cancers to therapeutic apoptosis-induction has thus far not been investigated. Here, we show that hyperosmotic stress lowers the threshold for apoptosis induction in malignant melanoma, the deadliest form of skin cancer. Hypertonic conditions enforce addiction to BCL-2-like proteins to prevent initiation of the mitochondria-regulated (intrinsic) apoptotic pathway. Essentially, hyperosmotic stress primes mitochondria for death. Our work identifies osmotic pressure in the tumor microenvironment as a cell extrinsic factor that modulates responsiveness of malignant melanoma cells to therapy.

Symptomatic Hyperglycemia in a Patient with Dialysis Ascites

An anuric woman with ascites rapidly developed extreme hyperglycemia and seizures after hemodialysis. During development of hyperglycemia, the decrease in serum sodium concentration (Δ[Na]) was nearly twice the value predicted by a formula accounting for the degree of hyperglycemia and the intracellular-to-extracellular volume ratio. The prediction assumed that ascitic fluid is part of the extracellular volume. Potential contributors to the development of seizures include the rapid development of severe hypertonicity, a remote history of seizure disorder and development of dialysis disequilibrium syndrome. Observations in peritoneal dialysis suggest that fluid with sodium concentration lower than in the ascitic fluid is transferred from the abdominal cavity into the blood during rapid development of hyperglycemia. In this case, Δ[Na], which determines the tonicity level expected after correction of hyperglycemia, resulted from exit of both intracellular and ascitic fluid into the extracellular compartment and, therefore, ascitic fluid functions as an extension of the intracellular fluid.

Hyperthermia and Rigidity Following Overdose of an Unknown Drug; A Case Report and Literature Review

Drug induced hyperthermia is a rare presentation which can rapidly lead to gross metabolic abnormality and death. These presentations are further complicated by the wide range of potentially causative agents. We present a case of rigidity and hyperthermia, following overdose of an initially unknown substance leading to challenging management decisions in the Emergency Department. This case was later identified as Serotonin Syndrome. The patient presented with trismus which was managed with rapid sequence induction of anaesthesia to allow airway protection. On extubation a significant degree of laryngeal oedema complicated weaning, a possible complication of Serotonin Syndrome not previously described in the literature. We discuss the pathophysiology of Serotonin Syndrome, important differentials and practical considerations in managing hypertonicity of unknown origin in a young person.

Fluid balance concepts in medicine: Principles and practice

The regulation of body fluid balance is a key concern in health and disease and comprises three concepts. The first concept pertains to the relationship between total body water (TBW) and total effective solute and is expressed in terms of the tonicity of the body fluids. Disturbances in tonicity are the main factor responsible for changes in cell volume, which can critically affect brain cell function and survival. Solutes distributed almost exclusively in the extracellular compartment (mainly sodium salts) and in the intracellular compartment (mainly potassium salts) contribute to tonicity, while solutes distributed in TBW have no effect on tonicity. The second body fluid balance concept relates to the regulation and measurement of abnormalities of sodium salt balance and extracellular volume. Estimation of extracellular volume is more complex and error prone than measurement of TBW. A key function of extracellular volume, which is defined as the effective arterial blood volume (EABV), is to ensure adequate perfusion of cells and organs. Other factors, including cardiac output, total and regional capacity of both arteries and veins, Starling forces in the capillaries, and gravity also affect the EABV. Collectively, these factors interact closely with extracellular volume and some of them undergo substantial changes in certain acute and chronic severe illnesses. Their changes result not only in extracellular volume expansion, but in the need for a larger extracellular volume compared with that of healthy individuals. Assessing extracellular volume in severe illness is challenging because the estimates of this volume by commonly used methods are prone to large errors in many illnesses. In addition, the optimal extracellular volume may vary from illness to illness, is only partially based on volume measurements by traditional methods, and has not been determined for each illness. Further research is needed to determine optimal extracellular volume levels in several illnesses. For these reasons, extracellular volume in severe illness merits a separate third concept of body fluid balance.

A Quick Reference on Hypernatremia

Hypernatremia most commonly is associated with water loss in excess of sodium or salt gain (typically associated with restriction of access to water). Most of the signs of hypernatremia arise from the central nervous system; the more rapid the development of hypernatremia, the more severe the neurologic signs are likely to be. Anorexia, lethargy, vomiting, muscular weakness, behavioral changes, disorientation, ataxia, seizures, coma, and death have been identified in dogs and cats with hypernatremia and hypertonicity.

Hypertonicity: Clinical entities, manifestations and treatment

Hypertonicity causes severe clinical manifestations and is associated with mortality and severe short-term and long-term neurological sequelae. The main clinical syndromes of hypertonicity are hypernatremia and hyperglycemia. Hypernatremia results from relative excess of body sodium over body water. Loss of water in excess of intake, gain of sodium salts in excess of losses or a combination of the two are the main mechanisms of hypernatremia. Hypernatremia can be hypervolemic, euvolemic or hypovolemic. The management of hypernatremia addresses both a quantitative replacement of water and, if present, sodium deficit, and correction of the underlying pathophysiologic process that led to hypernatremia. Hypertonicity in hyperglycemia has two components, solute gain secondary to glucose accumulation in the extracellular compartment and water loss through hyperglycemic osmotic diuresis in excess of the losses of sodium and potassium. Differentiating between these two components of hypertonicity has major therapeutic implications because the first component will be reversed simply by normalization of serum glucose concentration while the second component will require hypotonic fluid replacement. An estimate of the magnitude of the relative water deficit secondary to osmotic diuresis is obtained by the corrected sodium concentration, which represents a calculated value of the serum sodium concentration that would result from reduction of the serum glucose concentration to a normal level.

Active and Passive Components of Pelvic Floor Muscle Tone in Women with Provoked Vestibulodynia: A Perspective Based on a Review of the Literature

AIM

Pelvic floor muscle (PFM) dysfunctions, especially elevated tone or tension, are suggested to play an important role in the pathophysiology of provoked vestibulodynia (PVD). However, the involvement of the PFMs remains misunderstood as the assessment of muscle tone is complex and requires a thorough understanding of muscle physiology in relation to the characteristics and limitations of current PFM assessment tools. The aim of this review was to describe the structures and mechanisms involved in muscle tone in normally innervated muscle, and to discuss and relate these concepts to the PFM findings in women with PVD.

METHODS

A narrative overview of the literature retrieved from searches of electronic databases and hand searches.

RESULTS

Muscle tone in a normally innervated muscle comprises both active (contractile) and passive (viscoelastic) components. Current methods for evaluating PFM tone such as digital palpation, ultrasound imaging, pressure perineometry, dynamometry, and electromyography may evaluate different components. Research findings suggestive of PFM hypertonicity in women with PVD include elevated general PFM tone, changes in viscoelastic properties, and at least in some women, abnormal increases in electrogenic activity.

CONCLUSION

There is a growing body of evidence to support the involvement of PFM hypertonicity in the pathophysiology of PVD. Limitations of the instruments as well as their properties should be considered when evaluating PFM tone in order to obtain better insight into which component of PFM tone is assessed. Future research is required for further investigating the underlying mechanisms of PFM hypertonicity, and studying the specific effects of physiotherapeutic interventions on PFM tone in women with PVD.

Quantitative evaluation of Oryeongsan and its action on water regulation in renal inner medullary collecting duct cells

ETHNOPHARMACOLOGICAL RELEVANCE

Oryeongsan (ORS, Wulingsan) has been reported to possess renal protective effects from renal diseases such as diabetes-induced renal damage, and nephrocalcinosis.

AIM OF THE STUDY

This study was conducted to evaluate the quantitative analysis and the inhibitory effect of ORS on hypertonic stress-induced water channel and apoptosis in murine inner medullary collecting duct cell line (mIMCD-3).

MATERIALS AND METHODS

Chromatographic and NMR spectroscopic analysis were performed and water balance regulation was determined by Western blot, RT-PCR, and immunofluorescnece.

RESULTS

Seven active principles (5-hydroxymethylfurfural, alismoxide, methyl(-)trans-cinnamate, adenine, guanosine, adenosine, and ferulic acid) in ORS were isolated and the structures were identified mainly by NMR spectroscopic analysis. In addition, contents of these metabolites in ORS were evaluated by HPLC analysis. Pretreatment with ORS significantly attenuated the hypertonic stress (175mM NaCl)-induced increase in protein levels of AQP2 and apical membrane insertion. ORS also attenuated osmolyte sodium-myo-inositol transporter (SMIT) expression and tonicity-responsive enhancer binding protein (TonEBP) mRNA under hypertonic stress. Those actions of ORS presented the similar effect of PKA inhibitor which AQP2 expression throughout the inhibition of vasopressin-mediated cAMP/PKA signal pathway. On the other hand, pretreatment with ORS attenuated hypertonic stress-induced cell death. Hypertonic stress-induced Bax or caspase-3 expression was decreased by ORS, resulting in anti-apoptotic effect.

CONCLUSIONS

The present data suggest that the beneficial effect of ORS in water balance and apoptosis against hypertonic stress of renal collecting ducts.

Role of nuclear factor of activated T-cells 5 in regulating hypertonic-mediated secretin receptor expression in kidney collecting duct cells

A growing body of evidence suggests that secretin (SCT) is an important element in the osmoregulatory pathway. It is interesting to note that both SCT and its receptor (SCTR) gene are activated upon hyperosmolality in the kidney. However, the precise molecular mechanisms underlying the induction of the SCTR gene expression in response to changes in osmolality have yet to be clarified. Detailed DNA sequence analysis of the promoter regions of the SCTR gene reveals the presence of multiple osmotic response elements (ORE). The ORE is the binding site of a key osmosensitive transactivator, namely, the nuclear factor of activated T-cells 5 (NFAT5). SCTR and NFAT5 are co-expressed in the kidney cortex and medulla collecting duct cells. We therefore hypothesize that NFAT5 is responsible for modulating SCTR expression in hypertonic environments. In this study, we found hypertonicity stimulates the promoter activities and endogenous gene expression of SCTR in mouse kidney cortex collecting duct cells (M1) and inner medulla collecting duct cells (mIMCD3). The overexpression and silencing of NFAT5 further confirmed it to be responsible for the up-regulation of the SCTR gene under hypertonic conditions. A significant increase in the interaction between NFAT5 and the SCTR promoter was also observed following chromatin immunoprecipitation assay. In vivo, osmotic stress up-regulates the SCTR gene in the kidney cortex and medulla of wild-type mice, but does not do so in NFAT5(+/-) animals. Hence, this study provides comprehensive information on how NFAT5 regulates SCTR expression in different osmotic environments.

How do kinases contribute to tonicity-dependent regulation of the transcription factor NFAT5?

NFAT5 plays a critical role in maintaining the renal functions. Its dis-regulation in the kidney leads to or is associated with certain renal diseases or disorders, most notably the urinary concentration defect. Hypertonicity, which the kidney medulla is normally exposed to, activates NFAT5 through phosphorylation of a signaling molecule or NFAT5 itself. Hypotonicity inhibits NFAT5 through a similar mechanism. More than a dozen of protein and lipid kinases have been identified to contribute to tonicity-dependent regulation of NFAT5. Hypertonicity activates NFAT5 by increasing its nuclear localization and transactivating activity in the early phase and protein abundance in the late phase. The known mechanism for inhibition of NFAT5 by hypotonicity is a decrease of nuclear NFAT5. The present article reviews the effect of each kinase on NFAT5 nuclear localization, transactivation and protein abundance, and the relationship among these kinases, if known. Cyclosporine A and tacrolimus suppress immune reactions by inhibiting the phosphatase calcineurin-dependent activation of NFAT1. It is hoped that this review would stimulate the interest to seek explanations from the NFAT5 regulatory pathways for certain clinical presentations and to explore novel therapeutic approaches based on the pathways. On the basic science front, this review raises two interesting questions. The first one is how these kinases can specifically signal to NFAT5 in the context of hypertonicity or hypotonicity, because they also regulate other cellular activities and even opposite activities in some cases. The second one is why these many kinases, some of which might have redundant functions, are needed to regulate NFAT5 activity. This review reiterates the concept of signaling through cooperation. Cells need these kinases working in a coordinated way to provide the signaling specificity that is lacking in the individual one. Redundancy in regulation of NFAT5 is a critical strategy for cells to maintain robustness against hypertonic or hypotonic stress.

Expression, fermentation and purification of a predicted intrinsically disordered region of the transcription factor, NFAT5

Hypertonicity stimulates Nuclear Factor of Activated T-cells 5 (NFAT5) nuclear localization and transactivating activity. Many transcription factors are known to contain intrinsically disordered regions (IDRs) which become more structured with local environmental changes such as osmolality, temperature and tonicity. The transactivating domain of NFAT5 is predicted to be intrinsically disordered under normal tonicity, and under high NaCl, the activity of this domain is increased. To study the binding of co-regulatory proteins at IDRs a cDNA construct expressing the NFAT5 TAD was created and transformed into Escherichia coli cells. Transformed E. coli cells were mass produced by fermentation and extracted by cell lysis to release the NFAT5 TAD. The NFAT5 TAD was subsequently purified using a His-tag column, cation exchange chromatography as well as hydrophobic interaction chromatography and then characterized by mass spectrometry (MS).

Prolonged hypernatremia triggered by hyperglycemic hyperosmolar state with coma: A case report

A man with past lithium use for more than 15 years, but off lithium for two years and not carrying the diagnosis of diabetes mellitus or nephrogenic diabetes insipidus (NDI), presented with coma and hyperglycemic hyperosmolar state (HHS). Following correction of HHS, he developed persistent hypernatremia accompanied by large volumes of urine with low osmolality and no response to desmopressin injections. Urine osmolality remained < 300 mOsm/kg after injection of vasopressin. Improvement in serum sodium concentration followed the intake of large volumes of water plus administration of amiloride and hydrochlorothiazide. Severe hyperglycemia may trigger symptomatic lithium-induced NDI years after cessation of lithium therapy. Patients with new-onset diabetes mellitus who had been on prolonged lithium therapy in the past require monitoring of their serum sodium concentration after hyperglycemic episodes regardless of whether they do or do not carry the diagnosis of NDI.

Lethal neonatal rigidity and multifocal seizure syndrome--report of another family with a BRAT1 mutation

We describe two siblings born to consanguineous Arab-Muslim parents who presented in early infancy with myoclonic seizures, hypertonia and contractures, arrested head growth, inability to swallow, and bouts of apnea-bradycardia, culminating in cardiac arrest and death. Whole-genome sequencing yielded a c.1173delG mutation in the BRAT1 gene. Three recent reports identified mutations in the same gene in three infants from three Amish sibships, one Mexican neonate and two Japanese siblings with similar clinical manifestations. The authors speculated that the destabilization of the encoded protein may underlie the catastrophic epilepsy and corticobasal neuronal degeneration. We suggest that BRAT1 be added to the growing list of genes that are related to severe early infantile (neonatal) epileptic encephalopathy.

Canine paroxysmal movement disorders

Paroxysmal dyskinesias are episodic movement disorders characterized by muscle hypertonicity that can produce involuntary movements. Signs emanate from the central nervous system; consciousness is not impaired, ictal electroencephalography is normal, and there are no autonomic signs, distinguishing them from seizure disorders. In humans they are classified into 3 groups, each responding to different therapies. A mutation in the gene for brevican (BCAN) has been identified as the cause of Episodic Falling in Cavalier King Charles spaniels. Further elucidation of the genetic causes will enhance our ability to identify and treat these canine diseases.

Hypertonic Saline Attenuates the Pro-metastatic Effects of LPS by Reducing Tumor Cell Migration, Proliferation and MMP-9 Expression

Background

Lipopolysaccharide (LPS) promotes tumor metastases. The aim of this study was to determine the ability of a hypertonic environment to attenuate the pro metastatic properties of LPS both in vitro, and in vivo.

Methods

LPS stimulated, and unstimulated, 4T1 tumor cells were cultured in either an isotonic or hypertonic environment. The effect on invasion, migration, pro-matellomatrixproteinase 9 (proMMP-9) expression, proliferation, and microscopic cell structure was assessed. Lung metastases were induced in C57 mice with systemic hypertonicity in unstimulated and stimulated mice. The metastatic burden was assessed by estimation of lung/body weight ratio, pleural nodules and clonogenic assay.

Results

In vitro, a hypertonic environment reduced proMMP-9 expression (0.012 versus 1.16, P < 0.001) invasion (0.06 versus 0.119, P = 0.005), tumor cell proliferation (0.035 versus 0.041, P = 0.001), while inducing structural changes to tumor cells reducing overall cell volume. In vivo, the induction of transient systemic hypertonicity reduced metastatic burden as demonstrated by reduced lung nodules (4 versus 8, P = 0.004) and colonies on clonogenic assay (12 versus 43, P = 0.04).

Conclusion

The in vitro exposure of tumor cells to a hypertonic environment reduces tumor cell migration and proliferation. Transient systemic hypertonicity can reduce the metastatic burden following intra-operative exposure to LPS in vivo.

Modulation of NFAT-5, an outlying member of the NFAT family, in human keratinocytes and skin

BACKGROUND

Cyclosporin A (CsA) and tacrolimus block T cell activation by inhibiting the phosphatase calcineurin and preventing translocation from the cytoplasm to the nucleus of the transcription factor Nuclear Factor of Activated T cells (NFAT). NFAT compose a family of transcription factors that are turned on during T cell activation.

AIMS

To study the expression of NFAT-5 mRNA and protein in normal human keratinocytes and to investigate the cellular and subcellular pattern of expression of NFAT-5 in normal human skin and psoriasis, and analyze effects of different agonists and ultraviolet radiation on NFAT-5 in normal human skin.

METHODS

Tissue cultures, Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR), Western analysis, immunostaining, confocal microscopy.

RESULTS

Sequencing of RT-PCR products confirmed the identity of the product that showed 100 % homology with the predicted NFAT-5 sequence. anti-NFAT-5 mainly detected a single band in cultured keratinocytes and dermal fibroblasts using Western analysis. Immunohistochemistry showed that epidermal keratinocytes and dermal fibroblasts in normal human and psoriatic skin express NFAT-5. NFAT-5 showed predominantly nuclear localization in epidermal keratinocytes and dermal fibroblasts within five normal adult skin biopsies. Our data also suggest that UV irradiation reduces NFAT-5 nuclear localization within the epidermis. Unlike NFAT 1-4, NFAT-5/TonEBP was localized to both nucleus and cytoplasm of cultured keratinocytes. Cyclosporin A induces nuclear membrane translocation of NFAT-5 in cultured keratinocytes and raffinose (a hypertonicity inducing agent) induces more nuclear localization of NFAT-5 compared to untreated cells. In addition, differentiation-promoting agonists that induce sustained rise in intracellular calcium did not result in changes in NFAT-5 localization in cultured keratinocytes.

CONCLUSION

These studies provide the first observation of expression of NFAT-5/TonEBP mRNA protein in cultured keratinocytes and dermal fibroblasts and possible functional regulation in cultured keratinocytes. CsA and raffinose effects on NFAT-5/TonEBP in cultured keratinocytes suggest diverse intracellular signaling pathways for NFAT-5/TonEBP in these cells, and that NFAT-5/TonEBP might function to translate different extracellular stimuli into appropriate functional responses.