Screening for CLCN5 mutation in renal calcium stone formers patients

Thirty-five patients (23 males and 12 females), age 35 +/- 13 years old, presenting either idiopathic calcium nephrolithiasis, nephrocalcinosis or mild renal failure with idiopathic calcium nephrolithiasis were selected for the analysis of low molecular weight proteinuria and the possible mutations occurrence in the chloride channel gene CLCN5. The urinary ratio of beta2-microglobulin and creatinine (beta2M/Cr) was very high in a transplanted woman with nephrocalcinosis (> 3.23 mg/mmol) and slightly high in five patients (> 0.052 or < 1.0 mg/mmol) with multiple urological manipulations. Other studied patients showed beta2M/Cr ratio at normal range (0.003-0.052 mg/mmol) without gender difference (p > 0.05). Mutation analysis of CLCN5 gene was performed in 26 patients of 35 selected (11 with idiopathic hypercalciuria; 6 men with normal calciuria; 3 with mild renal insufficiency and 6 with nephrocalcinosis) and was normal in all subjects even in those with abnormal molecular weight proteinuria. Conclusion: CLCN5 gene mutation is not a common cause of kidney stone disease or nephrocalcinosis in a group of Brazilian patients studied.     

Multiple sequences in the C terminus of MaxiK channels are involved in expression, movement to the cell surface, and apical localization

Apical expression of the large-conductance, calcium- and voltage-activated potassium (MaxiK) channel in the cortical collecting duct is responsible for flow-stimulated potassium secretion. Here, we identify two cytoplasmic regions controlling apical expression of the MaxiK channel. Disruption of the proximal region results in the intracellular retention of the MaxiK channel without affecting channel assembly, thereby reducing surface expression. Coexpression of the WT channel with this mutant results in a reduction of WT MaxiK channel at the cell surface. Our data indicate that this proximal region is necessary for export of the MaxiK channel from the endoplasmic reticulum as a way to assess the final assembly of the channel. Deletion of a more distal region disrupts apical sorting, resulting in a nonpolarized distribution of the channel without impairing its surface delivery. In summary, we have found that sequences of amino acids in the C terminus of the MaxiK channel operate after the channel is assembled into a multimer and play a role in its expression, movement to the cell surface, and apical localization.     

Association of achalasia and pulmonary Mycobacterium fortuitum infection

A case of achalasia complicated by Mycobacterium fortuitum pulmonary infection and empyema is reported. This association has been documented in the medical literature. Possible mechanisms explaining this association are discussed.     

Bronchopulmonary dysplasia: radiographic appearance in middle childhood

Chest radiographs were compared for three groups of children 8-9 years old: 23 survivors of bronchopulmonary dysplasia (BPD), 33 survivors of hyaline membrane disease without BPD, and 35 survivors of premature birth without neonatal respiratory problems. Only four children in the second group and three in the third had abnormal lungs. Linear shadows, apparently representing strands of fibrosis or deep pleural fissuring, were seen more frequently (15 of 23) in the BPD group than in the others (P less than .0001). Seventeen children in the BPD group had definite pulmonary abnormalities, none of them severe. The anteroposterior dimension of the chest in survivors of BPD tended to be decreased (P less than .001 vs that of reported control subjects).     

A phase II,double-blind,randomized, placebo-controlled clinical trial of tgAAVCF using maxillary sinus delivery in patients with cystic fibrosis with antrostomies

tgAAVCF, an adeno-associated cystic fibrosis transmembrane conductance regulator (CFTR) viral vector/gene construct, was administered to 23 patients in a Phase II, double-blind, randomized, placebo-controlled clinical trial. For each patient, a dose of 100,000 replication units of tgAAVCF was administered to one maxillary sinus, while the contralateral maxillary sinus received a placebo treatment, thereby establishing an inpatient control. Neither the primary efficacy endpoint, defined as the rate of relapse of clinically defined, endoscopically diagnosed recurrent sinusitis, nor several secondary endpoints (sinus transepithelial potential difference [TEPD], histopathology, sinus fluid interleukin [IL]-8 measurements) achieved statistical significance when comparing treated to control sinuses within patients. One secondary endpoint, measurements of the anti-inflammatory cytokine IL-10 in sinus fluid, was significantly (p < 0.03) increased in the tgAAVCF-treated sinus relative to the placebo-treated sinus at day 90 after vector instillation. The tgAAVCF administration was well tolerated, without adverse respiratory events, and there was no evidence of enhanced inflammation in sinus histopathology or alterations in serum-neutralizing antibody titer to adeno-associated virus (AAV) capsid protein after vector administration. In summary, this Phase II trial confirms the safety of tgAAVCF but provides little support of its efficacy in the within-patient controlled sinus study. Various potentially confounding factors are discussed.     

振幅型光栅法人眼调制传递函数测定的理论分析

目的:介绍测量视网膜调制传递函数的方法和光学原理,验证振幅型正弦光栅加零级空间滤波的方法测量视网膜调制传递函数使测量仪器小型化的可行性。方法:目前测量仪器中获得两相干点光源主要是使用平行板法、双道威棱镜法和光栅法3种,从理论上分析比较3种方法的优劣性,并重点分析矩形光栅、振幅型正弦光栅的各级衍射光强分布特点。结果:①平板法和双道威棱镜法可获得两相干点光源,也是在视网膜调制传递函数测量仪中应用比较成熟的技术,其光学原理简单,获得相干点光源的相干性良好,光强稳定。另外,使用双道威棱镜法时,可以用电位带动反射镜的移动来控制两点光源的间距,易于装置的智能化控制,但所设计的仪器外观尺寸较大,移动性较差,不利于测量装置的手持式和小型化发展。②矩形光栅法可以实现仪器的小型化,但由于矩形光栅的衍射图样是单缝衍射图样与多光束干涉图样相互调制的结果,即衍射光强的多光束干涉条纹干扰测量结果。③振幅型正弦光栅的透过率函数可以实现0￣1,以余弦波形式对入射光波产生振幅调制,且衍射光强只有三级谱线(0级和±1级),且±1级谱线的光强分布具有对称性,只要进行零级空间滤波,就可以得到作为视标调制度的两个点光源。结论:振幅型正弦光栅加零级空间滤波可以获得相干性良好相干点光源,并且可以实现测量仪器的小型化。     

Correlation between DNA transfer and cystic fibrosis airway epithelial cell correction after recombinant adeno-associated virus serotype 2 gene therapy

Recombinant adeno-associated virus serotype 2 (rAAV2)-based human gene therapy for cystic fibrosis has progressed through a series of preclinical studies and phase I and II clinical trials. This agent has shown an encouraging safety profile, consistent levels of DNA transfer, and positive evidence of short-term clinical improvement in lung function in a prospective, placebo-controlled phase II trial of aerosol administration. Nonetheless, it has been difficult to assess the relationship between its molecular action and the observed clinical improvements, because of the lack of positive results from a highly specific assay for vector mRNA. This issue is further complicated by the fact that the clinical vector utilizes a small cryptic rAAV2 promoter sequence that is less robust for mRNA expression than typical viral promoters. In this paper, we report the results of more sensitive assays performed on primary nasal cells harvested from rAAV2-CFTR gene therapy recipients. These studies demonstrate a correlation between the presence of rAAV2-CFTR vector genomes, CFTR mRNA expression, and cAMP-activated chloride channel function in these cells. The observation of sizeable physiological correction in the face of low mRNA levels may reflect the regulatory role of low levels of CFTR protein as an activator of other chloride channels.