Outcomes of Salvage Surgery Versus Non-Salvage Surgery for Initially Unresectable Hepatocellular Carcinoma After Conversion Therapy with Transcatheter Arterial Chemoembolization Combined with Lenvatinib Plus Anti-PD-1 Antibody: A Multicenter Retrospective Study.

BACKGROUND: Combination treatment with transcatheter arterial chemoembolization (TACE), lenvatinib, and anti-programmed death-1 (anti-PD-1) antibodies (triple therapy) has a high rate of tumor response and converted resection for initially unresectable hepatocellular carcinoma (uHCC) patients. This study aimed to assess the outcomes of salvage surgery in uHCC patients after conversion therapy with triple therapy. METHODS: uHCC patients who met the criteria for hepatectomy after receiving triple therapy as first-line treatment were eligible for inclusion in this study. The overall survival (OS) and progression-free survival (PFS) rates in patients who received salvage surgery (SR group) and those who did not (non-SR group) were compared. RESULTS: Of the 144 patients assessed, 91 patients underwent salvage surgery and 53 did not. The OS rates in the SR group were significantly better than those in the non-SR group. The 1- and 2-year OS rates in the SR group were 92.0% and 79.9%, respectively, whereas those in the non-SR group were 85.5% and 39.6 %, respectively (p = 0.007); however, there was no significant difference in the PFS rates. Upon further stratification, OS and PFS were significantly better in the SR group than in the non-SR group in patients who were assessed as partial responses (PR), while there was no significant difference in patients who were assessed as complete response (CR). CONCLUSIONS: Salvage surgery is recommended and is associated with a favorable prognosis for uHCC patients who were assessed as PR after conversion therapy, however it may not be necessary for uHCC if CR was achieved.

Electroacupuncture with intermittent wave stimulation as rehabilitation approach for chronic Bell's palsy: a randomized controlled trial.

PURPOSE: To evaluate the effectiveness and safety of electroacupuncture (EA) using intermittent wave stimulation in enhancing facial symmetry and nerve function in chronic Bell's palsy patients. METHODS: A 6-week assessor-blinded, randomized trial followed by an 18-week observational period was conducted. Sixty individuals with chronic Bell's palsy, showing no signs of recovery after 12 months, were equally divided to receive either 18 sessions of EA using intermittent wave stimulation or Transcutaneous Electrical Stimulation (TES), administered thrice weekly over 6 weeks. The primary outcome measure was the change in the total facial nerve index (TFNI) score from baseline to Week 6, with secondary outcomes including TFNI scores at Weeks 12 and 24, as well as the change in Sunnybrook Facial Grading System (SFG) score from baseline to Week 6, and SFG scores at Weeks 12 and 24. RESULTS: The EA group showed a significant improvement, with a mean total facial nerve index score increase of 24.35 (4.77) by Week 6 compared with 14.21 (5.12) in the Transcutaneous Electrical Stimulation group (P<.001). This superiority persisted during the 24-week follow-up. While no significant difference was observed in the Sunnybrook Facial Grading System score change from baseline to Week 6, variations were noted at Weeks 12 and 24. No major adverse effects were reported. CONCLUSION: EA with intermittent wave stimulation notably enhanced facial symmetry in chronic Bell's palsy patients over Transcutaneous Electrical Stimulation by Week 6, maintaining this edge throughout the follow-up.

Elevated Interleukin-37 Associated with Dengue Viral Load in Patients with Dengue Fever.

Dengue remains a public health issue worldwide. Similar to chronic infectious diseases, stimulation of cytokine production is not enough to drive immune effector cells for effective virus clearance. One possible mechanism is the virus induces a large number of negative stimulatory cytokines inhibiting immune response. Interleukin 37 (IL-37) plays a crucial regulatory role in infection and immunity, inhibits innate and adaptive immunity as an anti-inflammatory cytokine by inhibiting proinflammatory mediators and pathways. To date, there are few studies reporting correlations between dengue fever (DF) and IL-37. In this study we found that the serum IL-37b and IL-37b-producing monocytes in patients were significantly increased in DF patients. A majority of the IL-37b produced by DF patients was produced by monocytes, not lymphocytes. Increased levels of IL-6, IL-10, and IFN-α were also found in DF patients. However, we failed to detect IL-1ß, IL-17A and TNF-α in plasma, because of off-target. In our study, there was no relation between IL-6, IL-10, and IFN-α expressions and IL-37b in serum (P > 0.05). The IL-37b-producing monocytes were negatively correlated with the level of IFN-α in serum and platelet count, and positively correlated with lymphocytes percentage (P < 0.05, respectively). Additionally, serum DENV nonstructural protein 1 levels were positively correlated with monocytes percentages (P < 0.05). Our data represents findings for IL-37b expression and its potential mechanisms in DF patients' immune response.

miR-24-3p Regulates Epithelial-Mesenchymal Transition and the Malignant Phenotype of Pancreatic Adenocarcinoma by Regulating ASF1B Expression.

Anti-silencing function protein 1 homolog B (ASF1B) has been implicated in the occurrence and development of cancers. The present work explored the functional role and the expression regulation of ASF1B in pancreatic ductal adenocarcinoma (PDAC). Based on the real-time quantitative PCR (qRT-PCR) and immunohistochemistry (IHC), ASF1B was significantly upregulated in PDAC tissues. High expression of ASF1B was associated with a poor overall survival (OS) and recurrence-free survival (DFS) in the PDAC patients. ASF1B also showed a relatively higher expression in PDAC cells (AsPC-1, PANC-1) when compared with human pancreatic ductal epithelial cells (HPDFe-6). CCK8 and clone formation assay demonstrated that silencing ASF1B impaired the proliferation in PANC-1 and AsPC-1 cells, and Annexin V-PI staining showed an increased level of apoptosis upon ASF1B silencing. ASF1B silencing also suppressed the migration and invasion in PDAC cells, as revealed by Transwell assays. We further showed that miR-24-3p was downregulated in PDAC tissues and cells, which functionally interacted with ASF1B by dual-luciferase reporter assay. miR-24-3p negatively regulated ASF1B expression to modulate the malignant phenotype of PDAC cells. ASF1B shows high expression in PDAC, which promotes the malignancy and EMT process of PDAC cells. miR-24-3p is a negative regulator of ASF1B and is downregulated in PDAC cells. Our data suggest that targeting ASF1B/miR-24-3p axis may serve as an intervention strategy for the management of PDAC.

Impact of Bile Duct Tumor Thrombus on the Long-Term Surgical Outcomes of Hepatocellular Carcinoma Patients: A Propensity Score Matching Analysis.

BACKGROUND: Hepatectomy with tumor thrombectomy is the preferred treatment option for hepatocellular carcinoma (HCC) patients with bile duct tumor thrombus (BDTT); however, the impact of BDTT on their prognosis is unclear. OBJECTIVE: We aimed to investigate the long-term surgical outcomes of HCC patients with BDTT. METHODS: The data of HCC patients with and without BDTT who underwent hepatectomy were retrospectively reviewed and the long-term outcomes were compared. For propensity score matching (PSM) analysis, patients were matched in a 1:1 ratio. Subgroup analysis was conducted according to the American Joint Committee on Cancer (AJCC) staging system. RESULTS: Before PSM, HCC patients with BDTT had more advanced tumor stages and adverse clinicopathological features. Recurrence-free survival (RFS) and overall survival (OS) were significantly higher in the non-BDTT group before PSM (RFS, p < 0.001; OS, p < 0.001), while after PSM, the BDTT group had significantly poorer RFS (p = 0.025). There was no difference in OS between the groups (p = 0.588). Subgroup analysis showed that RFS and OS in AJCC stage I-II patients were significantly poorer in the BDTT group; no differences were found in the AJCC stage III group before or after PSM. When the presence of BDTT was recommended to increase the AJCC staging system by one stage in AJCC stage I-II patients, the predictive ability for RFS and OS was higher. CONCLUSIONS: BDTT was associated with significantly poorer long-term surgical outcomes in AJCC stage I-II patients. A modified AJCC staging system including BDTT status in stage I-II might have a better prognostic ability.

Multiple endocrine neoplasia type 1 involving both the liver and lung: a case report.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant tumor syndrome with a high degree of heterogeneity in clinical phenotypes, generally involving the parathyroid, anterior pituitary, and enteropancreas. In recent years, several new insights into the clinical features of MEN1 have been reported in the literature. However, it is not clear whether MEN1-associated primary tumors can occur in the liver. CASE PRESENTATION: We report the case of a 52-year-old man with multiple endocrine neoplasia type 1 diagnosed by genetic sequencing. After uniportal thoracoscopic right middle lobectomy, laparoscopic radical resection of the liver tumors, and radiofrequency ablation of the parathyroid space, the parathyroid hormone level decreased from 177 pg/ml to a normal level (20 pg/ml). No local tumor recurrence was observed during a follow-up of 5 months. CONCLUSION: We report the first case of MEN1 with simultaneous liver and lung involvement in which the patient underwent radical resection of the tumors, and we propose the possibility that the liver and other nonendocrine organs may also develop diseases associated with MEN1; although, this view needs further verification. Gene detection has crucial clinical significance for guiding diagnosis and treatment.

The reference genome and transcriptome of the limestone langur, Trachypithecus leucocephalus, reveal expansion of genes related to alkali tolerance.

BACKGROUND: Trachypithecus leucocephalus, the white-headed langur, is a critically endangered primate that is endemic to the karst mountains in the southern Guangxi province of China. Studying the genomic and transcriptomic mechanisms underlying its local adaptation could help explain its persistence within a highly specialized ecological niche. RESULTS: In this study, we used PacBio sequencing and optical assembly and Hi-C analysis to create a high-quality de novo assembly of the T. leucocephalus genome. Annotation and functional enrichment revealed many genes involved in metabolism, transport, and homeostasis, and almost all of the positively selected genes were related to mineral ion binding. The transcriptomes of 12 tissues from three T. leucocephalus individuals showed that the great majority of genes involved in mineral absorption and calcium signaling were expressed, and their gene families were significantly expanded. For example, FTH1 primarily functions in iron storage and had 20 expanded copies. CONCLUSIONS: These results increase our understanding of the evolution of alkali tolerance and other traits necessary for the persistence of T. leucocephalus within an ecologically unique limestone karst environment.

KDF1 Novel Variant Causes Unique Dental and Oral Epithelial Defects.

Keratinocyte differentiation factor 1 (KDF1) is a recently identified and rare candidate gene for human tooth agenesis; however, KDF1-related morphological characteristics and pathological changes in dental tissue and the oral epithelium remain largely unknown. Here, we employed whole-exome sequencing (WES) and Sanger sequencing to screen for the suspected variants in a cohort of 151 tooth agenesis patients, and we segregated a novel KDF1 heterozygous missense variation, c.920G>C (p.R307P), in a non-syndromic tooth agenesis family. Essential bioinformatics analyses and tertiary structural predictions were performed to analyze the structural changes and functional impacts of the novel KDF1 variant. The subsequent functional assessment using a TOP-flash/FOP-flash luciferase reporter system demonstrated that KDF1 variants suppressed the activation of canonical Wnt signaling in 293T cells. To comprehensively investigate the KDF1-related oral morphological anomalies, we performed scanning electron microscopy and ground section of the lower right lateral deciduous incisor extracted from #285 proband, and histopathological assessment of the gingiva. The phenotypic analyses revealed a series of tooth morphological anomalies related to the KDF1 variant R307P, including a shovel-shaped lingual surface of incisors and cornicione-shaped marginal ridges with anomalous morphological occlusal grooves of premolars and molars. Notably, keratinized gingival epithelium abnormalities were revealed in the proband and characterized by epithelial dyskeratosis with residual nuclei, indistinct stratum granulosum, epithelial hyperproliferation, and impaired epithelial differentiation. Our findings revealed new developmental anomalies in the tooth and gingival epithelium of a non-syndromic tooth agenesis individual with a novel pathogenic KDF1 variant, broadening the phenotypic spectrum of KDF1-related disorders and providing new evidence for the crucial role of KDF1 in regulating human dental and oral epithelial development.

RhFGF21 Protects Epidermal Cells against UVB-Induced Apoptosis through Activating AMPK-Mediated Autophagy.

Ultraviolet irradiation, especially ultraviolet B (UVB) irradiation, increases the risks of various skin diseases, such as sunburn, photo-aging and cancer. However, few drugs are available to treat skin lesions. Therefore, the discovery of drugs to improve the health of irradiated skin is urgently needed. Fibroblast growth factor 21 (FGF21) is a metabolic factor that plays an important role in the protection and repair of various types of pathological damage. The effects of FGF21 on skin injury caused by UVB-irradiation were the focus of this study. We found that UVB irradiation promoted the expression of FGF21 protein in mouse epidermal cells, and exogenous recombinant human FGF21 (rhFGF21) protected mouse skin tissue against UVB-induced injury. RhFGF21 inhibited the inflammatory responses and epidermal cell apoptosis as well as promotion of autophagy in UVB-irradiated mice. Moreover, we found that rhFGF21 protected HaCaT cells against UVB-induced apoptosis, and the protective effect was enhanced by treatment with an autophagy activator (rapamycin) but was inhibited by treatment with an autophagy inhibitor (3-methyladenine, 3MA). AMP-activated protein kinase (AMPK), as a cellular energy sensor, regulates autophagy. RhFGF21 increased the expression of p-AMPK protein in epidermal cells irradiated with UVB in vivo and in vitro. Moreover, rhFGF21 increased autophagy levels and the viability were diminished by treatment with an AMPK inhibitor (compound C). RhFGF21 protects epidermal cells against UVB-induced apoptosis by inducing AMPK-mediated autophagy.

Genomic Mechanisms of Physiological and Morphological Adaptations of Limestone Langurs to Karst Habitats.

Knowledge of the physiological and morphological evolution and adaptation of nonhuman primates is critical to understand hominin origins, physiological ecology, morphological evolution, and applications in biomedicine. Particularly, limestone langurs represent a direct example of adaptations to the challenges of exploiting a high calcium and harsh environment. Here, we report a de novo genome assembly (Tfra_2.0) of a male François's langur (Trachypithecus francoisi) with contig N50 of 16.3 Mb and resequencing data of 23 individuals representing five limestone and four forest langur species. Comparative genomics reveals evidence for functional evolution in genes and gene families related to calcium signaling in the limestone langur genome, probably as an adaptation to naturally occurring high calcium levels present in water and plant resources in karst habitats. The genomic and functional analyses suggest that a single point mutation (Lys1905Arg) in the α1c subunit of the L-type voltage-gated calcium channel Cav1.2 (CACNA1C) attenuates the inward calcium current into the cells in vitro. Population genomic analyses and RNA-sequencing indicate that EDNRB is less expressed in white tail hair follicles of the white-headed langur (T. leucocephalus) compared with the black-colored François's langur and hence might be responsible for species-specific differences in body coloration. Our findings contribute to a new understanding of gene-environment interactions and physiomorphological adaptative mechanisms in ecologically specialized primate taxa.

PRRX1 deficiency induces mesenchymal-epithelial transition through PITX2/miR-200-dependent SLUG/CTNNB1 regulation in hepatocellular carcinoma.

Metastasis is a major obstacle to better prognosis in patients with hepatocellular carcinoma (HCC). Mesenchymal-epithelial transition (MET) is the driving force for metastatic colonization in which E-cadherin re-expression is a critical procedure. It has been reported that the loss of paired-related homeobox transcription factor 1 (PRRX1) is required for cancer cell metastasis. However, the role of PRRX1 in MET and how its downregulation triggers E-cadherin re-expression are unknown. In this study, we performed a systematic, mechanistic study regarding the role of PRRX1 in MET of HCC. We observed PRRX1 downregulation in HCC tissues, which correlated with early metastasis and short overall survival. Overexpression of PRRX1 induced epithelial-mesenchymal transition (EMT), but did not promote metastasis formation, while knockdown of PRRX1 promoted metastasis and colonization of circulating HCC cells as shown in animal model. PRRX1 protein levels reversely correlated with E-cadherin levels in HCC cell lines. PRRX1 knockdown promoted E-cadherin re-expression and cell proliferation and inhibited cell invasion and migration. The microarray results showed that PRRX1 deficiency regulated extracellular matrix (ECM) interaction, focal adhesion, TGF-ß signaling and cancer pathways. PRRX1 knockdown upregulated paired-like homeodomain 2 (PITX2) and inhibited catenin beta 1 (CTNNB1) and SNAIL family zinc finger 2 (SLUG). Silencing of PITX2 reversed CTNNB1 and SLUG inhibition and E-cadherin re-expression. PITX2 upregulation increased miR-200a and miR-200b/429, which further inhibited the transcription of CTNNB1 and SLUG, respectively, thus abrogating the inhibitory effect on E-cadherin. In conclusion, our data showed that the downregulation of PRRX1 induced E-cadherin re-expression through PITX2/miR-200a/CTNNB1 and PITX2/miR-200b/429/SLUG pathway.

Long-Term Outcomes of Anatomic Versus Nonanatomic Resection in Hepatocellular Carcinoma Patients with Bile Duct Tumor Thrombus: A Propensity Score Matching Analysis.

BACKGROUND: Anatomic resection (AR) of the liver is generally recommended in hepatocellular carcinoma (HCC) patients. However, the benefits of AR and nonanatomic resection (NAR) in HCC patients with bile duct tumor thrombus (BDTT) are unknown. This study aimed to compare long-term outcomes of AR and NAR in HCC patients with BDTT after curative resection. PATIENTS AND METHODS: A total of 175 consecutive HCC patients with BDTT after curative resection between April 2009 and December 2017 were included. One-to-one propensity score matching (PSM) was performed to minimize the influence of potential confounders. Recurrence-free survival (RFS) and overall survival (OS) were compared between the cohorts. RESULTS: After PSM, 120 patients were analyzed. The AR group had better RFS than the NAR group (P = 0.010). Even though there was no statistically significant difference in OS (P = 0.140, power = 0.33), the 3- and 5-year OS rates in the AR group (52.4% and 44.2%, respectively) were obviously higher than those in the NAR group (35.4% and 30.4%, respectively). When patients were further stratified according to tumor size, better RFS and OS were observed in patients with small (≤ 5 cm) tumors after AR (P < 0.001 and P = 0.004, respectively). Multivariate analysis identified AR (P = 0.024) as an independent favorable prognostic factor for RFS in HCC patients with BDTT. CONCLUSIONS: AR is recommended for HCC patients with BDTT, especially in patients with small (≤ 5 cm) tumors.

A nomogram based on combining systemic and hepatic inflammation markers for predicting microscopic bile duct tumour thrombus in hepatocellular carcinoma.

BACKGROUND: Bile duct invasion is a relatively rare event and is not well characterised in hepatocellular carcinoma (HCC). It remains very difficult to diagnose HCC with bile duct tumour thrombus (BDTT) before surgery. Increasing evidence has revealed that inflammation plays a critical role in tumorigenesis. This study aimed to develop nomograms based on systemic and hepatic inflammation markers to predict microscopic BDTT (micro-BDTT) before surgery in HCC. METHODS: A total of 723 HCC patients who underwent hepatectomy as initial therapy between January 2012 and June 2020 were included in the study. Logistic regression analysis was used to identify independent risk factors for micro-BDTT. The nomograms were constructed using significant predictors, including α-fetoprotein (AFP), alkaline phosphatase (ALP), direct bilirubin (DB), prognostic nutritional index (PNI), and γ-glutamyl transferase (γ-GT)/alanine aminotransferase (ALT). The prediction accuracies of the nomograms were evaluated using the area under the receiver operating characteristic (ROC) curve. RESULTS: AFP, ALP, DB, PNI, and γ-GT/ALT were independent risk factors for predicting micro-BDTT (P = 0.036, P = 0.004, P = 0.013, P = 0.012, and P = 0.006, respectively), which were assembled into the nomograms. The area under the ROC curve of the nomograms combining PNI and γ-GT/ALT for predicting micro-BDTT was 0.804 (95% confidence interval [CI]: 0.730-0.878). The sensitivity and specificity values when used in predicting micro-BDTT before surgery were 0.739 (95% CI: 0.612-0.866) and 0.781 (95% CI: 0.750-0.813), respectively. CONCLUSIONS: The nomogram based on combining systemic and hepatic inflammation markers is suitable for predicting micro-BDTT before surgery in HCC patients, leading to a rational therapeutic choice for HCC.

Quantitative prediction of bone mineral density by using bone turnover markers in response to antiresorptive agents in postmenopausal osteoporosis: A model-based meta-analysis.

AIMS: This study aimed to predict time course of bone mineral density (BMD) by using corresponding response of bone turnover markers (BTMs) in women with postmenopausal osteoporosis under antiresorptive treatments. METHODS: Data were extracted from literature searches in accessible public database. Time courses of percent change from baseline in serum C-telopeptide of type 1 collagen (sCTX) and N-telopeptide of type 1 collagen were described by complex exponential onset models. The relationship between BTM changes and BMD changes at lumbar spine and total hip was described using a multiscale indirect response model. RESULTS: The dataset included 41 eligible published trials of 5 US-approved antiresorptive agents (alendronate, ibandronate, risedronate, zoledronic acid and denosumab), containing over 28 800 women with postmenopausal osteoporosis. The time courses of BTM changes for different drugs were differentiated by maximal effect and onset rate in developed model, while sCTX responses to zoledronic acid and denosumab were captured by another model formation. Furthermore, asynchronous relationship between BTMs and BMD was described by a bone remodelling-based semimechanistic model, including zero-order production and first-order elimination induced by N-telopeptide of type 1 collagen and sCTX, separately. After external and informative validations, the developed models were able to predict BMD increase using 1-year data. CONCLUSION: This exploratory analysis built a quantitative framework linking BTMs and BMD among antiresorptive agents, as well as a modelling approach to enhance comprehension of dynamic relationship between early and later endpoints among agents in a certain mechanism of action. Moreover, the developed models can offer predictions of BMD from BTMs supporting early drug development.

High expression of OSR1 as a predictive biomarker for poor prognosis and lymph node metastasis in breast cancer.

PURPOSE: Oxidative stress-responsive kinase 1 (OSR1) plays a crucial role in regulating diverse cellular pathophysiologic functions, including ion homeostasis, development, differentiation, angiogenesis, invasive migration, and metastasis. Regardless, the clinical significance of OSR1 in breast cancer is scarce. The current study was conducted to evaluate the effect of OSR1 on the prognosis of patients with breast cancer with a long-term follow-up. METHODS: OSR1 expression in formalin-fixed and paraffin-embedded tissue specimens was analyzed. These specimens were collected from 551 evaluable breast cancer cases by immunohistochemistry (IHC). OSR1 expression was dichotomized based on the H-score in IHC. The effects of OSR1 levels on the clinicopathological attributes and survival prediction in patients with breast cancer were explored. RESULTS: Among 551 specimens, 183 (33.2%) exhibited high expression of OSR1 in tumor cells. High OSR1 levels were markedly correlated with histologic grade (P = 0.035), ER (P < 0.001) and PgR (P = 0.043) expression, lymph node involvement (P < 0.001), TNM stage (P < 0.001), and axillary surgery procedures (P = 0.003). Univariate analysis results indicate that patients with high OSR1 expression had significantly poor overall survival (P < 0.001), distant disease-free survival (P < 0.001), and breast cancer-specific survival (P < 0.001). Multivariable Cox regression analyses suggest that OSR1 expression was an independent predictive marker of poor prognosis and lymph node metastasis (HR 3.224, 95% CI 1.182-8.702, P = 0.023) in patients with breast cancer. CONCLUSIONS: Our findings indicate that OSR1 is a significantly independent prognosis index for patients with breast cancer with respect to distant disease-free survival, overall survival, and breast cancer-specific survival. High OSR1 expression caused an increase in deaths specifically attributed to breast cancer and was related to increased lymph node metastasis. However, the precise cellular mechanisms for OSR1 in breast cancer require further research.

Adaptive State Fidelity Estimation for Higher Dimensional Bipartite Entanglement.

An adaptive method for quantum state fidelity estimation in bipartite higher dimensional systems is established. This method employs state verifier operators which are constructed by local POVM operators and adapted to the measurement statistics in the computational basis. Employing this method, the state verifier operators that stabilize Bell-type entangled states are constructed explicitly. Together with an error operator in the computational basis, one can estimate the lower and upper bounds on the state fidelity for Bell-type entangled states in few measurement configurations. These bounds can be tighter than the fidelity bounds derived in [Bavaresco et al., Nature Physics (2018), 14, 1032-1037], if one constructs more than one local POVM measurements additional to the measurement in the computational basis.

A Missense Mutation A384P Associated with Human Hyperekplexia Reveals a Desensitization Site of Glycine Receptors.

Hyperekplexia, an inherited neuronal disorder characterized by exaggerated startle responses with unexpected sensory stimuli, is caused by dysfunction of glycinergic inhibitory transmission. From analysis of newly identified human hyperekplexia mutations in the glycine receptor (GlyR) α1 subunit, we found that an alanine-to-proline missense mutation (A384P) resulted in substantially higher desensitization level and lower agonist sensitivity of homomeric α1 GlyRs when expressed in HEK cells. The incorporation of the ß subunit fully reversed the reduction in agonist sensitivity and partially reversed the desensitization of α1A384P The heteromeric α1A384Pß GlyRs showed enhanced desensitization but unchanged agonist-induced maximum responses, surface expression, main channel conductance, and voltage dependence compared with that of the wild-type α1ß (α1WTß) GlyRs. Coexpression of the R392H and A384P mutant α1 subunits, which mimic the expression of the compound heterozygous mutation in a hyperekplexia patient, resulted in channel properties similar to those with α1A384P subunit expression alone. In comparison, another human hyperekplexia mutation α1P250T, which was previously reported to enhance desensitization, caused a strong reduction in maximum currents in addition to the altered desensitization. These results were further confirmed by overexpression of α1P250T or α1A384P subunits in cultured neurons isolated from SD rats of either sex. Moreover, the IPSC-like responses of cells expressing α1A384Pß induced by repeated glycine pulses showed a stronger frequency-dependent reduction than those expressing α1WTß. Together, our findings demonstrate that A384 is associated with the desensitization site of the α1 subunit and its proline mutation produced enhanced desensitization of GlyRs, which contributes to the pathogenesis of human hyperekplexia.SIGNIFICANCE STATEMENT Human startle disease is caused by impaired synaptic inhibition in the brainstem and spinal cord, which is due to either direct loss of GlyR channel function or reduced number of synaptic GlyRs. Considering that fast decay kinetics of GlyR-mediated inhibitory synaptic responses, the question was raised whether altered desensitization of GlyRs will cause dysfunction of glycine transmission and disease phenotypes. Here, we found that the α1 subunit mutation A384P, identified from startle disease patients, results in enhanced desensitization and leads to rapidly decreasing responses in the mutant GlyRs when they are activated repeatedly by the synaptic-like simulation. These observations suggest that the enhanced desensitization of postsynaptic GlyRs could be the primary pathogenic mechanism of human startle disease.

Expression, purification, and characterization of the Degludec precursor DesB30.

Diabetes is a chronic metabolic disease, for which recombinant human insulin is the most effective and mainstream treatment. DesB30 is an insulin analogue in which the B chain lacks amino acid 30 (Thr) compared with human insulin. This analogue can be used to produce the long-acting insulin Degludec or Detemir. In this study, a spacer peptide was added before the sequence of DesB30 and the C-peptide was replaced with AAK, a short connecting peptide. The target gene was cloned under the control of AOX1 and expressed as a secretory protein in Pichia pastoris. A high-yield recombination strain was selected by screening for resistance to G418. The basal salts medium was optimized and a lower salt concentration medium was found to show the best effects. Both media were used to compare the yield of high-density fermentation. The maximum yield reached 4.51 g/L in 1/2 basal salt medium, which is the highest reported yield to date. The insulin precursor, which is single-stranded, was purified by weak cation exchange chromatograph and preparative reversed-phase high-performance liquid chromatography (RP-HPLC), from which 73.39% of product was recovered at over 95% purity. The double-stranded protein (DesB30) was obtained by digesting the insulin precursor with trypsin. Using preparative RP-HPLC, the product was obtained with over 95% purity. Finally, the structure of DesB30 was confirmed.

Ultrafast Protonation of an Amide: Photoionization-Induced Proton Transfer in Phenol-Dimethylformamide Complex Cation.

In this study we explore the photoionization-induced proton transfer (PT) dynamics in the hydrogen-bonded complex of phenol (PhOH) and a simple amide, dimethylformamide (DMF). Neutral PhOH-DMF complexes produced in a supersonic expansion are photoionized by femtosecond 1 + 1 resonance-enhanced multiphoton ionization via its S1 state, and the subsequent PT dynamics occurring in the [PhOH-DMF]+ cation is probed by delayed pulses that lead to ion fragmentation. The experiments and density functional theory calculations reveal that the photoionization-induced PT proceeds in two consecutive steps of very different time scales. Upon femtosecond ionization the [PhOH-DMF]+ cation is initially prepared with a non-PT geometry close to that of the dominant neutral complex. The ionic system then rapidly relaxes into a configuration possessing both non-PT and PT characteristics in ∼0.5 ps. This partial-PT intermediate then undergoes a much slower barrier crossing in ∼25 ps to a more stable structure in which PT is more complete. The slow isomerization step not only corresponds to PT but also to a hydrogen-bonding site switching. The present study simulates a scenario of suddenly bringing a strong acid to the close vicinity of an amide to watch how protonation occurs. Our results suggest that the initial protonation of a peptide-like unit in acid-induced protein processes requires a relaxation time of ∼0.5 ps, which must be taken into account in complete descriptions of protein dynamics.