Novel variants and uncommon cases among southern Chinese children with X-linked hypophosphatemia

PURPOSE

X-linked hypophosphatemia (XLH) is the most common inherited renal phosphate wasting disorder and is often misdiagnosed as vitamin D deficiency. This study aims to provide clinical and mutational characteristics of 65 XLH pediatric patients in southern China.

METHODS

In this work, a combination of DNA sequencing and qPCR analysis was used to study the PHEX gene in 80 pediatric patients diagnosed with hypophosphatemia. The clinical and laboratory data of confirmed 65 XLH patients were assessed and analyzed retrospectively.

RESULTS

In 65 XLH patients from 61 families, 51 different variants in the PHEX gene were identified, including 23 previously reported variants and 28 novel variants. In this cohort of XLH patients, the c.1601C>T(p.Pro534Leu) variant appears more frequently. Fourteen uncommon XLH cases were described, including four boys with de novo mosaic variants, eight patients with large deletions and a pair of monozygotic twins. The clinical manifestations in this cohort are very similar to those previously reported.

CONCLUSION

This study extends the mutational spectrum of the PHEX gene, which will contribute to accurate diagnosis. This study also suggests a supplementary qPCR or MLPA assay may be performed along with classical sequencing to confirm the gross insertion/deletion.

Effect of bradykinin on rats with thromboangiitis obliterans through PI3K/Akt signaling pathway

OBJECTIVE

To explore the effect of bradykinin on rats with thromboangiitis obliterans (TAO) through the phosphatidylinositol 3-hydroxy kinase/protein kinase B (PI3K/Akt) signaling pathway.

MATERIALS AND METHODS

The female Wistar rats were injected with lauric acid via the femoral artery to establish the TAO model, and they were randomly divided into control group (healthy rats), model group (TAO rats) and bradykinin group (TAO rats injected with bradykinin B2 receptor-specific inhibitor). The control was set in each group before the operation. The level of serum bradykinin in each group was detected via enzyme-linked immunosorbent assay (ELISA), and the reactive oxygen species (ROS) level, Caspase-3 activity and PI3K/Akt protein concentration in vascular tissues were measured via ELISA, Western blotting, ROS assay, and Caspase-3 activity assay, respectively. Moreover, the specific therapeutic mechanism of bradykinin was analyzed.

RESULTS

In control group, the intima of the lower extremity venous tissues was smooth, the extima had no evident changes, and there was no inflammatory cell invasion around the arteries and veins. In model group, there was massive inflammatory cell invasion into the lower extremity venous tissues. In bradykinin group, fibrosis and atrophy occurred in venous tissues, the extima was thickened without fibrosis, and there was phagocytosis of neutrophils and mononuclear macrophages around the arteries and veins, as well as massive inflammatory infiltration. The PI3K/Akt protein concentration in lower extremity venous tissues was the highest in control group and the lowest in bradykinin group, and there were statistically significant differences (p<0.01). At 24 h after administration of doxorubicin (DOX), the level of ROS in lower extremity venous tissues was higher in bradykinin group than that in model group (p<0.05), and it was also higher in model group than that in control group (p<0.05). Besides, the activity of Caspase-3 in lower extremity venous tissues was significantly increased in bradykinin group compared with that in model group and control group, while it was slightly higher in model group than that in control group (p<0.05).

CONCLUSIONS

The low expression of bradykinin can promote TAO in rats by the mechanism that it inhibits the PI3K/Akt signaling pathway to raise the oxidative stress level, thereby aggravating TAO.

Molecular Mediation of Prion-like α-Synuclein Fibrillation from Toxic PFFs to Nontoxic Species

Braak's theory described Parkinson's disease (PD) progression as prion-like α-synuclein (αSyn) spreading, which fundamentally subverts the understanding of pathogenesis. The pathological αSyn spreading pathway includes uptake, propagation, and release. However, the previous disease models were limitedly focusing on amyloid propagation/aggregation, which significantly impedes the mechanism exploration in spreading pathways and related therapeutic development. The spreading model can be achieved using recombinant αSyn preformed fibrils (PFFs), which seeds endogenous αSyn monomer to aggregation and causes substantial pathology and neurotoxicity. Here, we determined that dihydromyricetin (DHM), a natural flavonoid extracted from Ampelopsis grossedentata, can promote the fibrillization of prion-like PFF and induce propagation to form a distinct strain. Furthermore, administration of DHM significantly reduced prion-like PFF-induced propagation and neurotoxicity. The discovery of inducing infectious and neurotoxic PFF to a nontoxic strain resulting in neuron protection via promoting the fibrillization of PFF rather than inhibiting advances the understanding of the prion-like spreading mechanism and helps in developing treatments against PD and related α-synucleinopathies.

Identification of the Potential Key Circular RNAs in Elderly Patients With Postoperative Cognitive Dysfunction

Background

Postoperative cognitive dysfunction (POCD) is one of the severe complications after surgery, inducing low life quality and high mortality, especially in elderly patients. However, the underlying molecular mechanism of POCD remains largely unknown, and the ideal biomarker for clinical diagnosis and prognosis is lacking. Circular RNAs (circRNAs), as a unique class of non-coding RNAs, were characterized by its stability and conservativeness, serving as novel biomarkers in various diseases. Nevertheless, the role of circRNAs in the occurrence of POCD remains elusive.

Methods

To investigate the differentially expressed circRNAs in the serum of POCD patients and its potential role in the development of POCD, we performed a circRNA microarray to screen the differentially expressed circRNAs in the serum samples from three patients of the POCD group and three paired patients of the non-POCD group. Subsequently, quantitative real-time polymerase chain reaction analysis (qRT-PCR) was utilized to verify the microarray data with the serum samples from 10 paired patients. Cytoscape software was used to construct the circRNA–miRNA–mRNA network for circRNAs with different expression levels as well as the target genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed the biological functions of the differentially expressed circRNAs target genes.

Results

In total, we have analyzed 10,198 circRNAs through the microarray. Compared with the non-POCD patient group, there were 210 differentially expressed circRNAs with 133 upregulated and 77 downregulated in the POCD group (≥2-fold differential expression, P ≤ 0.05). The qRT-PCR confirmed 10 circRNAs with different expressed levels, and the results were consistent with the microarray findings. Among them, hsa_circRNA_001145, hsa_circRNA_101138, and hsa_circRNA_061570 had the highest magnitude of change. The GO analysis showed that the differentially expressed circRNAs were associated with the regulation of the developmental process, cell-to-cell adhesion, and nervous system development. The KEGG analysis showed that the target genes of circRNAs were enriched in the MAPK signaling pathway and RAS signaling pathway. According to the targetscan7.1 and mirdbV5 databases, the circRNA–miRNA–mRNA network was constructed, and these results provided a vital landscape of circRNA expression profile in POCD.

Conclusions

Our study provides an essential perspective for the differential expression of circRNAs in POCD patients. Further studies need to be performed to explore their potential therapeutic roles in the development of POCD.

Parkin interacting substrate zinc finger protein 746 is a pathological mediator in Parkinson's disease

α-Synuclein misfolding and aggregation plays a major role in the pathogenesis of Parkinson's disease. Although loss of function mutations in the ubiquitin ligase, parkin, cause autosomal recessive Parkinson's disease, there is evidence that parkin is inactivated in sporadic Parkinson's disease. Whether parkin inactivation is a driver of neurodegeneration in sporadic Parkinson's disease or a mere spectator is unknown. Here we show that parkin in inactivated through c-Abelson kinase phosphorylation of parkin in three α-synuclein-induced models of neurodegeneration. This results in the accumulation of parkin interacting substrate protein (zinc finger protein 746) and aminoacyl tRNA synthetase complex interacting multifunctional protein 2 with increased parkin interacting substrate protein levels playing a critical role in α-synuclein-induced neurodegeneration, since knockout of parkin interacting substrate protein attenuates the degenerative process. Thus, accumulation of parkin interacting substrate protein links parkin inactivation and α-synuclein in a common pathogenic neurodegenerative pathway relevant to both sporadic and familial forms Parkinson's disease. Thus, suppression of parkin interacting substrate protein could be a potential therapeutic strategy to halt the progression of Parkinson's disease and related α-synucleinopathies.

The solar nebula origin of (486958) Arrokoth, a primordial contact binary in the Kuiper Belt

The New Horizons spacecraft's encounter with the cold classical Kuiper Belt object (486958) Arrokoth (provisional designation 2014 MU₆₉) revealed a contact-binary planetesimal. We investigated how Arrokoth formed and found that it is the product of a gentle, low-speed merger in the early Solar System. Its two lenticular lobes suggest low-velocity accumulation of numerous smaller planetesimals within a gravitationally collapsing cloud of solid particles. The geometric alignment of the lobes indicates that they were a co-orbiting binary that experienced angular momentum loss and subsequent merger, possibly because of dynamical friction and collisions within the cloud or later gas drag. Arrokoth's contact-binary shape was preserved by the benign dynamical and collisional environment of the cold classical Kuiper Belt and therefore informs the accretion processes that operated in the early Solar System.

FeSe quantum dots for in vivo multiphoton biomedical imaging

An immense demand in biomedical imaging is to develop efficient photoluminescent probes with high biocompatibility and quantum yield, as well as multiphoton absorption performance to improve penetration depth and spatial resolution. Here, iron selenide (FeSe) quantum dots (QDs) are reported to meet these criteria. The synthesized QDs exhibit two- and three-photon excitation property at 800- and 1080-nm wavelengths and high quantum yield (ca. 40%), which are suitable for second-window imaging. To verify their biosuitability, poly(ethylene glycol)-conjugated QDs were linked with human epidermal growth factor receptor 2 (HER2) antibodies for in vitro/in vivo two-photon imaging in HER2-overexpressed MCF7 cells and a xenograft breast tumor model in mice. Imaging was successfully carried out at a depth of up to 500 μm from the skin using a nonlinear femtosecond laser at an excitation wavelength of 800 nm. These findings may open up a way to apply biocompatible FeSe QDs to multiphoton cancer imaging.

The Diagonal Branch to the Accompanying Vein Fistula After Rotational Atherectomy

We report a case of rotational-atherectomy induced fistula between the diagonal branch and the accompanying vein. Thus far, the patient has had no relevant symptoms; thus, no intervention has been undertaken. We will closely monitor the patient to determine future treatment.

Lipopolysaccharide induces epithelial-mesenchymal transition of alveolar epithelial cells cocultured with macrophages possibly via the JAK2/STAT3 signaling pathway

Epithelial-mesenchymal transition (EMT) plays a key role in the process of pulmonary fibrosis (PF). Increasing evidences have shown that exaggerated EMT in recurrent pulmonary injury mediates the early pathogenesis of PF. This study aimed to evaluate EMT of human alveolar epithelial cells (A549) when cocultured with human macrophages Tohoku hospital pediatrics-1 (THP-1) induced by lipopolysaccharide (LPS) and investigate the role of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. Firstly, we detected the inflammatory and EMT biomarkers in A549 cells monoculture and A549/THP-1 cells coculture in the presence or absence of LPS. Then, the activation of JAK2/STAT3 signaling pathway was determined in coculture. Interestingly, inflammatory markers, such as interleukin (IL)-6, matrix metalloproteinase (MMP)-9, transforming growth factor (TGF)-β, and collagen type 1 (COL-1), were enhanced in LPS treated coculture. Besides, the expression of E-cadherin decreased but α-smooth muscle actin expression increased, indicating the presence of EMT in A549 cells when cocultured with THP-1 macrophages. However, these phenotypes could not be observed in LPS-treated A549 cells monoculture. Meanwhile, JAK2/STAT3 signaling pathway was activated, and the STAT3 DNA-binding and inflammatory markers were inhibited by Stattic. Together, these findings demonstrate the key role of JAK2/STAT3 signaling pathway in LPS promoted EMT of A549 in the presence of THP-1 macrophages as an in vitro PF model.

Extracellular RNAs-TLR3 signaling contributes to cognitive decline in a mouse model of postoperative cognitive dysfunction

Postoperative cognitive dysfunction (POCD) is considered a severe complication after surgery among elderly patients. Toll-like receptor 3 (TLR3) has recently been reported to play an important role in hippocampus-dependent working memory. However, the role of TLR3 in the development of POCD remains unclear. In the current study, we hypothesized that increased extracellular RNAs (exRNAs) during anesthesia and surgical operation, especially double stranded RNAs (dsRNAs), would activate TLR3 signaling pathways and mediate POCD. Using a mouse model of POCD, 20-22 months wild-type (WT) mice were undergoing unilateral nephrectomy and increased TLR3 expression levels and co-localization with neuronal and microglial cells were found in the surgery group compared with the sham group. Compared with WT mice, TLR3 knockout (KO, ^-/-) mice had improved hippocampus-dependent memory and attenuated production of inflammatory cytokines and apoptosis. Increased exRNAs and/or co-localization with TLR3 were found in both in vitro and in vivo models. Of note, TLR3/dsRNA complex inhibitor administration reduced hippocampal dsRNA level and TLR3 expression, attenuated hippocampal inflammatory cytokines production and apoptosis, and thus improved hippocampus-dependent memory. Our results indicate that exRNAs, especially dsRNAs, present under stressful conditions may trigger TLR3 activation and initiate the downstream inflammatory and apoptotic signaling, and play a substantial role in the development of POCD.

Identification of the Potential Key Long Non-coding RNAs in Aged Mice With Postoperative Cognitive Dysfunction

Postoperative cognitive dysfunction (POCD) is a significant complication of surgery, particularly in elderly patients. Emerging researches showed that long non-coding RNA (lncRNA) may play a vital role in the pathogenesis of POCD. Here we aimed to identify potential key lncRNAs involved in the development of POCD. LncRNA and mRNA expression profiles in hippocampal tissues from POCD and control mice were analyzed by microarray assay. Gene ontology (GO) and KEGG pathway enrichment analyses were conducted to probe the functions of dysregulated genes. Then, important factors of the mainly affected biological processes were measured in the hippocampus. Correlated coding–non-coding co-expression (CNC) networks were constructed. Finally, the potential key pairs of lncRNA and target mRNA implicated in POCD were probed. Our data showed that 868 differentially expressed lncRNAs and 690 differentially expressed mRNAs were identified in total. GO and KEGG analyses indicated that the differentially expressed genes were mainly associated with inflammatory and apoptotic signaling pathways. Surgery-induced inflammatory cytokines and apoptosis were significantly increased in hippocampal tissues of aged mice. In CNC network analysis, we found that LncRNA uc009qbj.1 was positively correlated with apoptosis-associated gene Vrk2 level. LncRNA ENSMUST00000174338 correlated positively with expression of the inflammation and apoptosis-associated gene Smad7. LncRNA NONMMUT00000123687 mediated gene expression by binding the inflammation-regulated transcription factor Meis2. Our results suggested that these potential key lncRNAs and mRNAs may play a crucial role in the development of POCD through mediating neuronal inflammation or apoptosis.

Phenotypic analysis of atopic dermatitis in children aged 1-12 months: elaboration of novel diagnostic criteria for infants in China and estimation of prevalence

BACKGROUND

Atopic dermatitis (AD) is the most common skin disorder in infancy. However, the diagnosis and definite significance of infantile AD remains a debated issue.

OBJECTIVE

To analyse the phenotypes of AD in infancy, to establish diagnostic criteria and to estimate the prevalence of this condition in China.

METHODS

This is a multicentric study, in which 12 locations were chosen from different metropolitan areas of China. Following careful and complete history-taking and skin examination, the definite diagnosis of AD was made and the severity based on the SCORAD index was determined by local experienced dermatologists. Based on the detailed phenotyping, the major and representative clinical features of infantile AD were selected to establish the diagnostic criteria and evaluate their diagnostic efficacy.

RESULTS

A total of 5967 infants were included in this study. The overall point prevalence of AD was 30.48%. The infantile AD developed as early as at the second month of life, and its incidence peaked in the third month of life at 40.81%. The proportion of mild, moderate and severe AD was 67.40%, 30.57% and 2.03%, respectively. The most commonly seen manifestations in the infantile AD were facial dermatitis (72.07%), xerosis (42.72%) and scalp dermatitis (27.93%). We established the novel diagnostic criteria of infants, which included: (i) onset after 2 weeks of birth; (ii) pruritus and/or irritability and sleeplessness comparable with lesions; and (iii) all two items above with one of the following items can reach a diagnosis of AD: (i) eczematous lesions distributed on cheeks and/or scalp and/or extensor limbs, and (ii) eczematous lesions on any other parts of body accompanied by xerosis.

CONCLUSIONS

In China, the prevalence of AD in infancy is 30.48% according to clinical diagnosis of dermatologists. The novel Chinese diagnostic criteria for AD in infants show a higher sensitivity and comparable specificity.

[Acceptability of pre-exposure HIV prophylaxis clinical trial among MSM in Shenyang city]

Objective: To investigate the acceptability and related factors of an "on-demand" pre-exposure prophylaxis (PrEP) to prevent HIV transmission among MSM in Shenyang. Methods: MSM recruited by non-probability sampling method and questionnaire survey conducted by investigators to collect information on social and behavioral characteristics, awareness of PrEP, Truvada and the acceptability of two different PrEP-based trials. Multivariate logistic regression was employed for statistical analysis. Results: Among the 292 respondents, 34.2% had heard of PrEP and 58.2% (170/292) reported were interested in participating a PrEP trial- "on-demand" use or 48.3% (141/292) interested on "daily" use (χ(2)=5.785, P=0.02). Factors independently associated with those "on-demand" would include: having more than 2 male sexual partners during the past 6 month (aOR=1.7, 95%CI: 1.1-2.7), concerning on the positive effect of PrEP (vs. side effects) (aOR=6.4, 95%CI:2.2-18.9), having an HIV-infected sexual partners (aOR=8.1, 95%CI: 1.0-63.3) and self-reported high risk for HIV (aOR=2.6, 95%CI: 1.2-6.0). The last two factors were only associated with the "on-demand" group. Conclusions: "On-demand" PrEP (as opposed to daily) seemed a more feasible prevention strategy on HIV and particularly in those having high risk behavior of HIV. For those who could not follow the daily medication or having HIV risk perception, "On-demand" basis PrEP trial should be recommended for them to follow.

State transitions in the substantia nigra reticulata predict the onset of motor deficits in models of progressive dopamine depletion in mice

Parkinson's disease (PD) is a progressive neurodegenerative disorder whose cardinal motor symptoms are attributed to dysfunction of basal ganglia circuits under conditions of low dopamine. Despite well-established physiological criteria to define basal ganglia dysfunction, correlations between individual parameters and motor symptoms are often weak, challenging their predictive validity and causal contributions to behavior. One limitation is that basal ganglia pathophysiology is studied only at end-stages of depletion, leaving an impoverished understanding of when deficits emerge and how they evolve over the course of depletion. In this study, we use toxin- and neurodegeneration-induced mouse models of dopamine depletion to establish the physiological trajectory by which the substantia nigra reticulata (SNr) transitions from the healthy to the diseased state. We find that physiological progression in the SNr proceeds in discrete state transitions that are highly stereotyped across models and correlate well with the prodromal and symptomatic stages of behavior.