Moderate/Severe Hyponatremia Increases the Risk of Death among Hospitalized Chinese Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome Patients

Objectives

To evaluate whether the serum sodium concentration is associated with the progression and long-term prognosis of Chinese HIV/AIDS patients.

Methods

Three hundred and eighty seven hospitalized patients were recruited into this retrospective cohort study. The strata of serum sodium concentration were moderate/severe hyponatremia, mild hyponatremia and normonatremia. Disease progression was estimated using CD4 counts and the WHO clinical stage. Correlation analysis was used to evaluate the serum sodium concentration with disease progression. The Kaplan-Meier method and the Cox proportional hazards model were used to analyze the effect of different serum sodium levels on survival.

Results

In this study 206 patients (53.2%) had hyponatremia, including 10.6% patients with moderate/severe hyponatremia and 42.6% with mild hyponatremia. The serum sodium concentration was significantly correlated with the HIV/AIDS progression (P<0.001). During the follow-up, 100 patients (25.6%) died. The cumulative survival rates of HIV/AIDS patients were 47.8%±8.5% in patients with moderate/severe hyponatremia, 59.8%±5.0% with mild hyponatremia and 79.9%±3.4% with normonatremia (log-rank P<0.001). After adjusting for sex, age, WHO stage, CD4 count, hemoglobin and albumin, the relative hazard was 3.5 (95% CI: 1.9–6.5) for patients with moderate/severe hyponatremia (P<0.001), and 1.5 (95% CI: 0.9–2.4) for those with mild hyponatremia (P = 0.161), compared with normonatremic patients.

Conclusions

The serum sodium level is closely correlated with the severity of patients. Only moderate/severe hyponatremia affects the prognosis of Chinese HIV/AIDS patients. Earlier intensive medical managements(including HAART)are necessary to increase the survival rates of Chinese HIV/AIDS patients with moderate/severe hyponatremia.     

Expression of the hyperpolarization-activated cyclic nucleotide-gated cation channel HCN4 during mouse heart development

HCN4 is a hyperpolarization-activated nucleotide-gated cation channel involved in the generation of the I(f) current that drives cardiac pacemaker activity. Previous studies have demonstrated that HCN4 is highly expressed in a restricted manner in adult sinoatrial (SA) node [Eur. J. Biochem. 268 (2001) 1646]. However, its developmental expression pattern is unknown. We have examined expression of HCN4 mRNA during mouse heart development. HCN4 mRNA was first detected in the cardiac crescent at embryonic day (ED) 7.5. At ED 8 it was symmetrically located in the most caudal portion of the heart tube, the sinus venosus where pacemaker activity has previously been reported [Am. J. Physiol. 212 (1967) 407]. With further development, HCN4 expression became asymmetrically distributed, occupying the dorsal wall of the right atria, and was progressively restricted to the junction of the right atrial appendage and the superior vena cava. The site of HCN4 expression in late embryonic heart coincided with the location of the SA node in postnatal and adult heart [Cardiovasc. Res. 52 (2001) 51]. Our results suggest that HCN4 may be a unique marker of the developing SA node.     

Geometrical versus Random β-TCP Scaffolds: Exploring the Effects on Schwann Cell Growth and Behavior

Numerous studies have demonstrated that Schwann cells (SCs) play a role in nerve regeneration; however, their role in innervating a bioceramic scaffold for potential application in bone regeneration is still unknown. Here we report the cell growth and functional behavior of SCs on β-tricalcium phosphate (β-TCP) scaffolds arranged in 3D printed-lattice (P-β-TCP) and randomly-porous, template-casted (N-β-TCP) structures. Our results indicate that SCs proliferated well and expressed the phenotypic markers p75^LNGFR and the S100-β subunit of SCs as well as displayed growth morphology on both scaffolds, but SCs showed spindle-shaped morphology with a significant degree of SCs alignment on the P-β-TCP scaffolds, seen to a lesser degree in the N-β-TCP scaffold. The gene expressions of nerve growth factor (β-ngf), neutrophin–3 (nt–3), platelet-derived growth factor (pdgf-bb), and vascular endothelial growth factor (vegf-a) were higher at day 7 than at day 14. While no significant differences in protein secretion were measured between these last two time points, the scaffolds promoted the protein secretion at day 3 compared to that on the cell culture plates. These results together imply that the β-TCP scaffolds can support SC cell growth and that the 3D-printed scaffold appeared to significantly promote the alignment of SCs along the struts. Further studies are needed to investigate the early and late stage relationship between gene expression and protein secretion of SCs on the scaffolds with refined characteristics, thus better exploring the potential of SCs to support vascularization and innervation in synthetic bone grafts.     

大鼠脑内代谢型谷氨酸受体5亚型(mGluR5)定位分布的免疫细胞化学研究

本研究用免疫细胞化学技术观察了大鼠脑内参与兴奋性突触传递的代谢型谷氨酸受体5亚型(mGluR5)的精确定位分布.mGluR5阳性浓染的神经元胞体和纤维密集地分布于大脑皮质浅层、嗅球、伏核、尾壳核、前脑基底部、隔区、苍白球、腹侧苍白球、海马CA1和CA2区、下丘中央核、被盖背侧核和三叉神经脊束核尾侧亚核浅层;淡染而稀疏的mGluR5阳性神经元胞体和纤维见于屏状核、终纹床核、杏仁中央核、丘脑部分核团、上丘浅灰质层、外侧丘系背侧核和延髓中央灰质.     

The heterotrimeric G‐protein β subunit,AGB1, plays multiple roles in the Arabidopsis salinity response

Salinity stress includes both osmotic and ionic toxicity. Sodium homeostasis is influenced by Na⁺ uptake and extrusion, vacuolar Na⁺ compartmentation and root to shoot Na⁺ translocation via transpiration. The knockout mutant of the Arabidopsis heterotrimeric G‐protein Gβ subunit, agb1, is hypersensitive to salt, exhibiting a leaf bleaching phenotype. We show that AGB1 is mainly involved in the ionic toxicity component of salinity stress and plays roles in multiple processes of Na⁺ homeostasis. agb1 mutants accumulate more Na⁺ and less K⁺ in both shoots and roots of hydroponically grown plants, as measured by inductively coupled plasma atomic emission spectrometry. agb1 plants have higher root to shoot translocation rates of radiolabelled ²⁴Na⁺ under transpiring conditions, as a result of larger stomatal apertures and increased stomatal conductance. ²⁴Na⁺ tracer experiments also show that ²⁴Na⁺ uptake rates by excised roots of agb1 and wild type are initially equal, but that agb1 has higher net Na⁺ uptake at 90 min, implicating possible involvement of AGB1 in the regulation of Na⁺ efflux. Calcium alleviates the salt hypersensitivity of agb1 by reducing Na⁺ accumulation to below the toxicity threshold. Our results provide new insights into the regulatory pathways underlying plant responses to salinity stress, an important agricultural problem.