Rhoptry antigens as Toxoplasma gondii vaccine target

Toxoplasmosis is a cosmopolitan zoonotic infection, caused by a unicellular protozoan parasite known as Toxoplasma gondii that belongs to the phylum Apicomplexa. It is estimated that over one-third of the world's population has been exposed and are latently infected with the parasite. In humans, toxoplasmosis is predominantly asymptomatic in immunocompetent persons, while among immunocompromised individuals may be cause severe and progressive complications with poor prognosis. Moreover, seronegative pregnant mothers are other risk groups for acquiring the infection. The life cycle of T. gondii is very complex, indicating the presence of a plurality of antigenic epitopes. Despite of great advances, recognize and construct novel vaccines for prevent and control of toxoplasmosis in both humans and animals is still remains a great challenge for researchers to select potential protein sequences as the ideal antigens. Notably, in several past years, constant efforts of researchers have made considerable advances to elucidate the different aspects of the cell and molecular biology of T. gondii mainly on microneme antigens, dense granule antigens, surface antigens, and rhoptry proteins (ROP). These attempts thereby provided great impetus to the present focus on vaccine development, according to the defined subcellular components of the parasite. Although, currently there is no commercial vaccine for use in humans. Among the main identified T. gondii antigens, ROPs appear as a putative vaccine candidate that are vital for invasion procedure as well as survival within host cells. Overall, it is estimated that they occupy about 1%–30% of the total parasite cell volume. In this review, we have summarized the recent progress of ROP-based vaccine development through various strategies from DNA vaccines, epitope or multi epitope-based vaccines, recombinant protein vaccines to vaccines based on live-attenuated vectors and prime-boost strategies in different mouse models.

In Vitro Evaluation of Fusiform-Shaped Stents for Wide-Neck Intracranial Aneurysm Treatment / 신경중재치료의학

PURPOSE: Wide-neck aneurysms (WNAs) associated with a dilated parent artery (PA) are not uncommon morphological abnormalities and usually cause inappropriate wall apposition and incomplete neck coverage of a tubular stent in stent-assisted coiling of aneurysms. We aimed to introduce a fusiform-shaped stent (FSS) and test its effectiveness in treating intracranial WNAs associated with a dilated PA using a three-dimensional (3D) model. MATERIALS AND METHODS: Two FSS types were designed with the middle one-third segment dilated by 10% (FSS10) and 20% (FSS20) and were compared with the tubular-shaped stent (TSS). A patient-specific 3D WNA model was prototyped and produced, and in vitro stent placement was performed. Angiographic images of the three stent types were analyzed and compared using predetermined parameters. RESULTS: The stent lumens were significantly larger in FSS10 and FSS20 than in TSS in the middle segments (P=0.046), particularly FSS20 (P=0.018). The non-covered area at the ostium tended to be smaller in FSS10 and FSS20 than in TSS, but the difference was not significant (P>0.05). The stent length was significantly longer in FSS10 and FSS20 than in TSS. The stent cell size was significantly larger in FSS than in TSS. CONCLUSION: Better vessel wall apposition and aneurysmal neck coverage was observed for FSS than for TSS. No significant difference was observed between FSS10 and FSS20.

Red blood cell distribution width is a independent prognostic indicator for mortality in patients with HBV related acute-on-chronic liver failure / 南方医科大学学报

OBJECTIVE@#To establish a model for predicting the short-term prognosis of patients with HBV-related acute-onchronic liver failure (HBV-ACLF) based on red blood cell distribution width (RDW) and the model for end-stage liver disease (MELD) scores.@*METHODS@#A total of 245 patients with HBV-ACLF were retrospectively analyzed for their clinical data and results of routine hematological tests, liver function, renal function, coagulation test, HBV-DNA, and other indicators at admission. Univariate analysis and binary logistic regression analysis were used to test the short-term risk factors for death of the patients, and the MELD-RDW model was established. The accuracy of each index and the established model was verified using the ROC curve.@*RESULTS@#The surviving patients with HBV-ACLF had significantly decreased RDW (14.97 ± 1.38) and MELD score (23.54±4.35) compared with those in the patients dead within 90 days (17.05±2.92 and 28.95±5.99, respectively). Multivariate analysis indicated that RDW was a significant independent prognostic factor for mortality in patients with HBVACLF (OR=1.840, 95%CI: 1.47902.289, < 0.005). The risk assessment model was [logisticMELD-RDW]=-9.375+0.582×RDW- 0.091×ALB-0.05×PTA+0.186×MELD. The area under the ROC curve of MELD score combined with RDW was 0.878, which was higher than RDW (0.724) and MELD score (0.780) alone.@*CONCLUSIONS@#RDW is an independent prognostic indicator for mortality in patients with HBV-ACLF. Compared with MELD score, the risk assessment model based on MELD and RDW has a greater value in predicting the short-term prognosis of patients with HBV-ACLF.

Pulmonary Hypertension in Connective Tissue Disease is Associated with the New York Heart Association Functional Class and Forced Vital Capacity, But Not with Interstitial Lung Disease

OBJECTIVE: Pulmonary hypertension (PH) develops frequently in connective tissue diseases (CTD) and is an important prognostic factor. The aim of this study was to assess the prevalence of PH in patients with CTD by non-invasive echocardiography and analyze the potential biomarkers for helping to detect PH. METHODS: All Korean patients with CTD who had dyspnea on exertion or interstitial lung disease (ILD) were screened for PH with echocardiography and clinical data were collected from four hospitals. RESULTS: Among 196 patients with CTD, 108 (55.1%) had ILD and 21 had PH defined as >40 mmHg. Of the 21 patients with PH, 10, 4, and 3 patients had systemic sclerosis, systemic lupus erythematosus, and mixed connective tissue disease, respectively. There was no difference in the incidence of PH according to the presence of ILD; 12 patients (11.1%) with ILD had PH and 9 patients (10.2%) without ILD had PH. The results of the pulmonary function test, total cholesterol, red cell volume distribution width, alkaline phosphatase, and the New York Heart Association (NYHA) functional class III or IV differed significantly according to the presence of PH. In multiple regression analysis, NYHA functional class III or IV (odd ratio [OR]=7.3, p=0.009) and forced vital capacity (OR=0.97, p=0.043) were independent predictive factors of PH. CONCLUSION: PH is not associated with the presence of ILD in Korean patients with CTD. On the other hand, NYHA functional class III or IV and decreased forced vital capacity indicate the presence of PH in connective tissue disease.

Up-regulation of NHE8 by somatostatin ameliorates the diarrhea symptom in infectious colitis mice model

Na⁺/H⁺ exchangers (NHEs) have been shown to be involved in regulating cell volume and maintaining fluid and electrolyte homeostasis. Pooled evidences have suggested that loss of Na⁺/H⁺ exchanger isoform 8 (NHE8) impairs intestinal mucosa. Whether NHE8 participates in the pathology of infectious colitis is still unknown. Our previous study demonstrated that somatostatin (SST) could stimulate the expression of intestinal NHE8 so as to facilitate Na⁺ absorption under normal condition. This study further explored whether NHE8 participates in the pathological processes of infectious colitis and the effects of SST on intestinal NHE8 expression in the setting of infectious colitis. Our data showed that NHE8 expression was reduced in Citrobacter rodentium (CR) infected mice. Up-regulation of NHE8 improved diarrhea symptom and mucosal damage induced by CR. In vitro, a similar observation was also seen in Enteropathogenic E. coli (EPEC) infected Caco-2 cells. Seglitide, a SST receptor (SSTR) 2 agonist, partly reversed the inhibiting action of EPEC on NHE8 expression, but SSTR5 agonist (L-817,818) had no effect on the expression of NHE8. Moreover, SST blocked the phosphorylation of p38 in EPEC-infected Caco-2 cells. Taken together, these results suggest that enhancement of intestinal NHE8 expression by SST could ameliorate the symptoms of mice with infectious colitis.

Effects of metformin on hyperglycemia in an experimental model of tacrolimus- and sirolimus-induced diabetic rats

BACKGROUND/AIMS: Metformin (MET) is a first-line drug for type 2 diabetes mellitus (DM); its effect on new-onset diabetes after transplantation caused by immunosuppressant therapy is unclear. We compared the effects of MET on DM caused by tacrolimus (TAC) or sirolimus (SRL). METHODS: DM was induced by injection of TAC (1.5 mg/kg) or SRL (0.3 mg/kg) for 2 weeks in rats, and MET (200 mg/kg) was injected for 2 more weeks. The effects of MET on DM caused by TAC or SRL were evaluated using an intraperitoneal glucose tolerance test (IPGTT) and by measuring plasma insulin concentration, islet size, and glucose-stimulated insulin secretion (GSIS). The effects of MET on the expression of adenosine monophosphate-activated protein kinase (AMPK), a pharmacological target of MET, were compared between TAC- and SRL-treated islets. RESULTS: IPGTT showed that both TAC and SRL induced hyperglycemia and reduced plasma insulin concentration compared with vehicle. These changes were reversed by addition of MET to SRL but not to TAC. Pancreatic islet cell size was decreased by TAC but not by SRL, but addition of MET did not affect pancreatic islet cell size in either group. MET significantly increased GSIS in SRL- but not in TAC-treated rats. AMPK expression was not affected by TAC but was significantly decreased in SRL-treated islets. Addition of MET restored AMPK expression in SRL-treated islets but not in TAC-treated islets. CONCLUSIONS: MET has different effects on hyperglycemia caused by TAC and SRL. The discrepancy between these drugs is related to their different mechanisms causing DM.

Induction of Apoptosis with Moringa oleifera Fruits in HCT116 Human Colon Cancer Cells Via Intrinsic Pathway

Moringa oleifera Lam (M. oleifera, Moringaceae) is a tree of the Moringaceae family that can reach a height of between 5 and 10 m. The current paper presents cytotoxic effect of M. oleifera fruits and its flavonoids 1 and 2. The viability of HCT116 human colon cancer cells were 38.5% reduced by 150 µg/mL of ethanolic extracts in a concentration-dependent manner; in addition, we observed the apoptotic features of cell shrinkage and decreased cell size. Bcl-2 family proteins were regulated as determined by Western blotting analysis, suggesting that M. oleifera fruits and their flavonoids 1 and 2 induced apoptosis through an intrinsic pathway. Based on our findings, 70% ethanolic extracts of M. oleifera fruits and flavonoids 1 and 2 might be useful as cytotoxic agents in colorectal cancer therapy.

Effects of AQP1 overexpression on morphology and water transport in mouse Schwann cells / 中华整形外科杂志

<p><b>OBJECTIVE</b>To determine the effect of AQP1 gene on facial nerve edema following injury through investigation of the relationship between the expression of AQP1 gene and Schwann cells swelling.</p><p><b>METHODS</b>The AQP1 expression in Schwann cells of mouse facial nerve tissues was detected by immunofluorescent staining. The transgenic protocol by lentivirus transduction was used to specifically upregulate AQP1 expression in Schwann cells. Lenti-AQP1 and CTRL (empty vector) transduced cells were observed during gene overexpression every 24 h for 6 days by using phase contrast microscopy. Cell volume of CTRL and Lenti-AQP1 treated cells was measured daily from the day of treatment, through day 6.</p><p><b>RESULTS</b>Schwann cell primary cultures maintained a high level of AQP1 water channels, representing an ideal cell model to study the role of AQP1 in the facial nerve. The expression of AQP1 mRNA and protein in Schwann cells infected with the Lenti-AQP1 was increased significantly compared with CTRL lentivirus (P < 0.05). Lenti-AQP1 caused cell swelling in cultured Schwann cells, as validated by cell volume determinations (P < 0.01).</p><p><b>CONCLUSIONS</b>AQP1 is an important factor responsible for the fast water transport of cultured Schwann cells. It plays an important role in facial nerve edema.</p>

Fluoride Induces a Volume Reduction in CA1 Hippocampal Slices Via MAP Kinase Pathway Through Volume Regulated Anion Channels

Regulation of cell volume is an important aspect of cellular homeostasis during neural activity. This volume regulation is thought to be mediated by activation of specific transporters, aquaporin, and volume regulated anion channels (VRAC). In cultured astrocytes, it was reported that swelling-induced mitogen-activated protein (MAP) kinase activation is required to open VRAC, which are thought to be important in regulatory volume decrease and in the response of CNS to trauma and excitotoxicity. It has been also described that sodium fluoride (NaF), a recognized G-protein activator and protein phosphatase inhibitor, leads to a significant MAP kinase activation in endothelial cells. However, NaF's effect in volume regulation in the brain is not known yet. Here, we investigated the mechanism of NaF-induced volume change in rat and mouse hippocampal slices using intrinsic optical signal (IOS) recording, in which we measured relative changes in intracellular and extracellular volume as changes in light transmittance through brain slices. We found that NaF (1~5 mM) application induced a reduction in light transmittance (decreased volume) in CA1 hippocampus, which was completely reversed by MAP kinase inhibitor U0126 (10 µM). We also observed that NaF-induced volume reduction was blocked by anion channel blockers, suggesting that NaF-induced volume reduction could be mediated by VRAC. Overall, our results propose a novel molecular mechanism of NaF-induced volume reduction via MAP kinase signaling pathway by activation of VRAC.

Fluoride Induces a Volume Reduction in CA1 Hippocampal Slices Via MAP Kinase Pathway Through Volume Regulated Anion Channels

Regulation of cell volume is an important aspect of cellular homeostasis during neural activity. This volume regulation is thought to be mediated by activation of specific transporters, aquaporin, and volume regulated anion channels (VRAC). In cultured astrocytes, it was reported that swelling-induced mitogen-activated protein (MAP) kinase activation is required to open VRAC, which are thought to be important in regulatory volume decrease and in the response of CNS to trauma and excitotoxicity. It has been also described that sodium fluoride (NaF), a recognized G-protein activator and protein phosphatase inhibitor, leads to a significant MAP kinase activation in endothelial cells. However, NaF's effect in volume regulation in the brain is not known yet. Here, we investigated the mechanism of NaF-induced volume change in rat and mouse hippocampal slices using intrinsic optical signal (IOS) recording, in which we measured relative changes in intracellular and extracellular volume as changes in light transmittance through brain slices. We found that NaF (1~5 mM) application induced a reduction in light transmittance (decreased volume) in CA1 hippocampus, which was completely reversed by MAP kinase inhibitor U0126 (10 µM). We also observed that NaF-induced volume reduction was blocked by anion channel blockers, suggesting that NaF-induced volume reduction could be mediated by VRAC. Overall, our results propose a novel molecular mechanism of NaF-induced volume reduction via MAP kinase signaling pathway by activation of VRAC.

5-Aza-2'-deoxycytidine acts as a modulator of chondrocyte hypertrophy and maturation in chick caudal region chondrocytes in culture / 대한해부학회지

This study was carried out to explore the effect of DNA hypomethylation on chondrocytes phenotype, in particular the effect on chondrocyte hypertrophy, maturation, and apoptosis. Chondrocytes derived from caudal region of day 17 embryonic chick sterna were pretreated with hypomethylating drug 5-aza-2'-deoxycytidine for 48 hours and then maintained in the normal culture medium for up to 14 days. Histological studies showed distinct morphological changes occurred in the pretreated cultures when compared to the control cultures. The pretreated chondrocytes after 7 days in culture became bigger in size and acquired more flattened fibroblastic phenotype as well as a loss of cartilage specific extracellular matrix. Scanning electron microscopy at day 7 showed chondrocytes to have increased in cell volume and at day 14 in culture the extracellular matrix of the pretreated cultures showed regular fibrillar structure heavily embedded with matrix vesicles, which is the characteristic feature of chondrocyte hypertrophy. Transmission electron microscopic studies indicated the terminal fate of the hypertrophic cells in culture. The pretreated chondrocytes grown for 14 days in culture showed two types of cells: dark cells which had condense chromatin in dark patches and dark cytoplasm. The other light chondrocytes appeared to be heavily loaded with endoplasmic reticulum indicative of very active protein and secretory activity; their cytoplasm had large vacuoles and disintegrating cytoplasm. The biosynthetic profile showed that the pretreated cultures were actively synthesizing and secreting type X collagen and alkaline phosphatase as a major biosynthetic product.

Hematologic and serum biochemical reference intervals of the Oriental white stork (Ciconia boyciana) and the application of an automatic hematologic analyzer

This study was conducted to establish accurate baseline values of clinical laboratory data with regard to age-related changes in the Oriental white stork (Ciconia boyciana). In addition, the availability of an automated hematological cell counter was evaluated. A total of 94 clinically normal storks, including 64 young storks ( 1 year old; 17 male and 13 female) were included. Hematological assays were performed using manual and automated cell counters and serum biochemistry profiles were examined using an automated analyzer. There were no significant differences in any parameters between male and female storks, while 16 parameters were significantly different between young and adult storks. Of these 16 parameters, total protein, albumin, aspartate aminotransferase, alanine aminotransferase, creatinine, triglyceride, total bilirubin, potassium, white blood cell count, packed cell volume, mean cell volume and hemoglobin levels were higher in adult storks than in young storks, while the latter showed higher glucose, uric acid and alkaline phosphatase levels, as well as a higher sodium/potassium ratio. The results presented herein will aid researchers who work for the conservation and rehabilitation of this endangered species.

Characterization of Senescence of Culture-expanded Human Adipose-derived Mesenchymal Stem Cells

BACKGROUND AND OBJECTIVES: Adipose-derived mesenchymal stem cells (ADSCs) are promising candidates in regenerative medicine. The need for in vitro propagation to obtain therapeutic quantities of the cells imposes a risk of impaired functionality due to cellular senescence. The aim of the study was to analyze in vitro senescence of previously cryopreserved human ADSCs subjected to serial passages in cell culture. METHODS AND RESULTS: ADSC cultures from 8 donors were cultivated until proliferation arrest was reached. A gradual decline of ADSC fitness was observed by altered cell morphology, loss of proliferative, clonogenic and differentiation abilities and increased β-galactosidase expression all of which occurred in a donor-specific manner. Relative telomere length (RTL) analysis revealed that only three tested cultures encountered replicative senescence. The presence of two ADSC subsets with significantly different RTL and cell size was discovered. The heterogeneity of ADSC cultures was supported by the intermittent nature of aging seen in tested samples. CONCLUSION: We conclude that the onset of in vitro senescence of ADSCs is a strongly donor-specific process which is complicated by the intricate dynamics of cell subsets present in ADSC population. This complexity needs to be carefully considered when elaborating protocols for personalized cellular therapy.

Estimation of the cultured cells' volume and surface area: application of stereological methods on vero cells infected by Rubella virus

Background: Morphological changes of the cells infected with rubella virus cannot be observed easily. Estimation of the size of the cultured cells can be a valuable parameter in this condition. This study was conducted to find answers to the following questions: - How much time after infection with rubella virus, the volume and surface area of the Vero cells and their nuclei get started to change? - How is it possible to apply stereological methods to estimate the volume and surface area of the cultured cells using the invariator, nucleator, and surfactor techniques?

Methods: The cultured Vero cells were infected with rubella virus. The cells of the control and experimental groups were harvested at 2, 4, 8, 24, and 48 hours following the incubation period. The cells were processed and embedded in paraffin. Invariator, nucleator, and surfactor were applied to estimate the size of the Vero cells and their nuclei

Results: The cell volume was decreased by 15-24%, 48 hours after the infection in comparison to the non-infected cells. Besides, the cell surface area was decreased by 13%, 48 hours after the infection. However, no changes were detected in the nuclei. The values of the standard deviation and coefficient of variation of the cells, estimated by invariator, were lower compared to those measured by the nucleator or surfactor

Conclusion: In this study, the volume and surface area of the Vero cells were reduced by rubella virus 48 hours after infection. Invariator is a more precise method compared to nucleator or surfactor

Autism in Brazil: a systematic review of family challenges and coping strategies / Autismo no Brasil, desafios familiares e estratégias de superação: revisão sistemática

OBJECTIVE: To describe the challenges faced by families caring for children with autism spectrum disorder (ASD) in Brazil and the coping strategies employed. SOURCES: Systematic review of articles published until September of 2013, without language restrictions, using quality appraisal (AMSTAR and CASP/Oxford instruments). SUMMARY OF THE FINDINGS: The literature shows parental emotional overload as one of the main challenges faced by families, especially mothers. The main stressors were diagnostic postponement, difficulty dealing with the diagnosis and associated symptoms, and poor access to health services and social support. The predominant coping strategies found included information exchange between affected families and integrated healthcare network for patient and family support. CONCLUSION: ASD exerts strong influence on family dynamics, resulting in caregiver overload, especially in mothers. The Brazilian Unified Health System needs to provide comprehensive, continuous, and coordinated care to strengthen the patient-family dyad and promote the full development and societal inclusion of children with ASD. .

OBJETIVO: Descrever os desafios encontrados pelas famílias na convivência com crianças portadoras de transtorno do espectro autista (TEA) no Brasil e as estratégias de superação empregadas. FONTE DOS DADOS: Revisão sistemática da literatura com inclusão de artigos publicados até setembro de 2013, sem restrições de idioma. Os artigos incluídos foram submetidos à avaliação de qualidade metodológica por meio do Amstar e Casp/Oxford. SÍNTESE DOS DADOS: Incluem-se estudos provenientes de São Paulo e Rio Grande do Sul com alta e moderada qualidade metodológica. A literatura mostra sobrecarga emocional dos pais como um dos principais desafios encontrados pelas famílias, inclusive com grande tensão sobre as mães. Dentre os fatores relacionados ao estresse estão: postergação diagnóstica, dificuldade de lidar com o diagnóstico e com os sintomas associados, acesso precário ao serviço de saúde e apoio social. Dentre as estratégias de superação destacaram-se: troca de informações entre as famílias afetadas e assistência integralizada da rede de saúde no atendimento do paciente e suporte à família. CONCLUSÃO: Observou-se que o TEA exerce forte influência na dinâmica familiar com sobrecarga dos cuidadores, geralmente da mãe. O Sistema Único de Saúde necessita prover cuidado integral, longitudinal e coordenado com vistas ao fortalecimento do binômio paciente-família e o pleno desenvolvimento e a plena inserção dessas crianças na sociedade. .

Isolation, culture, and identification of human spermatogonial stem cells / 中华男科学杂志

<p><b>OBJECTIVE</b>To isolate, identify and culture human spermatogonial stem cells (SSC) and then obtain purified and enriched human SSCs for research and application.</p><p><b>METHODS</b>We detected the expression of CD90 in the human testis using the immunofluorescence technique and isolated human testicular spermatogenic cells by two-step enzymatic digestion, followed by differential plating and magnetic-activated cell sorting (MACS) with CD90 as an SSC marker. Then we identified the isolated CD90-positive spermatogenic cells by RT-PCR and immunocytochemistry, and meanwhile cocultured them with Sertoli cells in SG medium in vitro.</p><p><b>RESULTS</b>The isolated CD90-positive cells showed a relatively homogeneous characteristic in size and morphology and expressed the genes specific for human SSCs, with high expressions (90.5%) of GFRA1, GPR125, and UCHL1. After coculture with Sertoli cells in the SG medium for 2 weeks, the isolated CD90-positive cells maintained a good activity.</p><p><b>CONCLUSION</b>CD90 can be regarded as a speci- fic marker for human SSCs and used to obtain highly enriched human SSCs by differential plating and MACS. Furthermore, the isolated human SSCs can be cultured in SG medium in vitro.</p>

Development of myenteric plexus in human foetuses: a quantitative study / 대한해부학회지

Maturation of neurons of the myenteric plexus (MP) of human fetal sigmoid colon was studied at various weeks of gestation (WG). There is abundant literature on the development of MP in various segments of the gut but there are fewer reports on the development of MP in human sigmoid colon which is a site of various disorders. Sigmoid colonic segments from 12 aborted foetuses aged 14-23WG were processed for NADPH histochemistry. Stereologic evaluation of the neuronal cell profiles, numerical density, number of neurons per ganglion and myenteric fraction was conducted using using imageJ software. According to gestational age, foetuses were assigned into two groups (group 1 [n=7], less than 17WG). The overall size of neuronal cell profiles in the MP was significantly increased (P<0.05). The numerical density of neurons decreased in group 2 in comparison to group 1, the number of neurons per ganglion and myenteric fraction were increased in group 2 but all these were not statistically significant. This study revealed that the maturational event increases after 17WG and extensive innervations is established at 23WG. During prenatal life there is an increase in the neuronal cell size from 14-23WG signifying maturational process. Such studies are essential for clinicians and surgeons to correlate the normal and pathologic development of the enteric nervous system.

Use of Bioelectrical Impedance Analysis for Nutritional Treatment in Critically Ill Patients

Patients in the intensive care unit (ICU) easily have large amounts of extracellular fluids, such as edema or ascites, because of cardiovascular instability under septic conditions and also have high risk of malnutrition while staying in the ICU. Traditional nutritional assessment parameters like body mass index have a limitation in ICU patients due to muscle atrophy and decrease of lean body mass. Bioimpedence analyses (BIA) can be used to assess body composition and are useful in performance of nutritional assessments in ICU patients. BIA can simply and noninvasively estimate body composition (total body water, extracellular water, intracellular water, body cell mass, and free fat mass etc.) by sending a weak electric current through the body. In particular, phase angle (PhA, phase difference between the voltage applied to the impedance and the current driven through it), one of the parameters of BIA, is related to cell membrane integrity or cell size. Low PhA can possibly imply malnutrition and PhA has been reported as a useful indicator of clinical outcomes or prognosis of severe patients. Additional study with clinical application of BIA in ICU patients is needed in order to confirm the usefulness of BIA.

Scorpion toxin BmK I directly activates Nav1.8 in primary sensory neurons to induce neuronal hyperexcitability in rats

Voltage-gated sodium channels (VGSCs) in primary sensory neurons play a key role in transmitting pain signals to the central nervous system. BmK I, a site-3 sodium channel-specific toxin from scorpion Buthus martensi Karsch, induces pain behaviors in rats. However, the subtypes of VGSCs targeted by BmK I were not entirely clear. We therefore investigated the effects of BmK I on the current amplitude, gating and kinetic properties of Nav1.8, which is associated with neuronal hyperexcitability in DRG neurons. It was found that BmK I dose-dependently increased Nav1.8 current in small-sized (<25 μm) acutely dissociated DRG neurons, which correlated with its inhibition on both fast and slow inactivation. Moreover, voltage-dependent activation and steady-state inactivation curves of Nav1.8 were shifted in a hyperpolarized direction. Thus, BmK I reduced the threshold of neuronal excitability and increased action potential firing in DRG neurons. In conclusion, our data clearly demonstrated that BmK I modulated Nav1.8 remarkably, suggesting BmK I as a valuable probe for studying Nav1.8. And Nav1.8 is an important target related to BmK I-evoked pain.