Accidental ingestion of multiple magnetic beads by children and their impact on the gastrointestinal tract: a single-center study.

OBJECTIVE: In this study, we aimed to enhance the treatment protocols and help understand the harm caused by the accidental ingestion of magnetic beads by children. METHODS: Data were collected from 72 children with multiple gastrointestinal perforations or gastrointestinal obstructions. The 72 pediatric patients were divided into a perforation and a non-perforation group. The data collected for the analysis included the gender, age, medical history, place of residence (rural or urban), and symptoms along with the educational background of the caregiver, the location and quantity of any foreign bodies discovered during the procedure, whether perforation was confirmed during the procedure, and the number of times magnetic beads had been accidentally ingested. RESULTS: The accuracy rate of preoperative gastrointestinal perforation diagnosis via ultrasound was 71%, while that of the upright abdominal X-ray method was only 46%. In terms of symptoms, the risk of perforation was 13.844 and 12.703 times greater in pediatric patients who experienced vomiting and abdominal pain with vomiting and abdominal distension, respectively, compared to patients in an asymptomatic state. There were no statistical differences between the perforation and the non-perforation groups in terms of age, gender, medical history, and the number of magnetic beads ingested (P > 0.05); however, there were statistical differences in terms of white blood cell count (P = 0.048) and c-reactive protein levels (P = 0.033). A total of 56% of cases underwent a laparotomy along with perforation repair and 19% underwent gastroscopy along with laparotomy. All pediatric patients recovered without complications following surgery. CONCLUSION: Abdominal ultrasonography and/or upright abdominal X-ray analyses should be carried out as soon as possible in case of suspicion of accidental ingestion of magnetic beads by children. In most cases, immediate surgical intervention is required. Given the serious consequences of ingesting this type of foreign body, it is essential to inform parents and/or caregivers about the importance of preventing young children from using such products.

Inhibition of endogenous hydrogen sulfide production suppresses the growth of nasopharyngeal carcinoma cells.

Hydrogen sulfide (H2 S) has been widely recognized as one of gasotransmitters. Endogenous H2 S plays a crucial role in the progression of cancer. However, the effect of endogenous H2 S on the development of nasopharyngeal carcinoma (NPC) is still unknown. In this study, aminooxyacetic acid (AOAA, an inhibitor of cystathionine-ß-synthase), dl-propargylglycine (PAG, an inhibitor of cystathionine-γ-lyase), and l-aspartic acid (l-Asp, an inhibitor of 3-mercaptopyruvate sulfurtransferase) were adopted to detect the role of endogenous H2 S in NPC growth. The results indicated that the combine (PAG + AOAA + l-Asp) group had higher inhibitory effect on the growth of NPC cells than the PAG, AOAA, and l-Asp groups. There were similar trends in the levels of apoptosis and reactive oxygen species (ROS). In addition, the combine group exhibited lower levels of phospho (p)-extracellular signal-regulated protein kinase but higher expressions of p-p38 and p-c-Jun N-terminal kinase than those in the AOAA, PAG, and l-Asp groups. Furthermore, the combine group exerted more potent inhibitory effect on NPC xenograft tumor growth without obvious toxicity. In summary, suppression of endogenous H2 S generation could dramatically inhibit NPC growth via the ROS/mitogen-activated protein kinase pathway. Endogenous H2 S may be a novel therapeutic target in human NPC cells. Effective inhibitors for H2 S-producing enzymes could be designed and developed for NPC treatment.

Actinomycin D: a novel Pseudomonas aeruginosa quorum sensing inhibitor from the endophyte Streptomyces cyaneochromogenes RC1.

The infections caused by Pseudomonas aeruginosa are difficult to treat due to its multidrug resistance. A promising strategy for controlling P. aeruginosa infection is targeting the quorum sensing (QS) system. Actinomycin D isolated from the metabolite of endophyte Streptomyces cyaneochromogenes RC1 exhibited good anti-QS activity against P. aeruginosa PAO1. Actinomycin D (50, 100, and 200 µg/mL) significantly inhibited the motility as well as reduced the production of multiple virulence factors including pyocyanin, protease, rhamnolipid, and siderophores. The images of confocal laser scanning microscopy and scanning electron microscopy revealed that the treatment of actinomycin D resulted in a looser and flatter biofilm structure. Real-time quantitative PCR analysis showed that the expression of QS-related genes lasI, rhlI, rhlR, pqsR, pslA, and pilA were downregulated dramatically. The production of QS signaling molecules N-(3-oxododecanoyl)-L-homoserine lactone and N-butanoyl-L-homoserine lactone were also decreased by actinomycin D. These findings suggest that actinomycin D, a potent in vitro anti-virulence agent, is a promising candidate to treat P. aeruginosa infection by interfering with the QS systems.

Overexpression of miR-329-3p sensitizes osteosarcoma cells to cisplatin through suppression of glucose metabolism by targeting LDHA.

Osteosarcoma (OS) is one of the most frequent malignant bone tumor types. Traditional treatments of OS involve standard chemotherapy or combination with radiation before and after surgery. Cisplatin is one of the most effective chemotherapeutic drugs used for treating osteosarcoma. However, patients with advanced tumor stages develop cisplatin resistance, leading to a major clinical challenge. In this study, we investigated the roles of miR-329-3p in cisplatin sensitivity of osteosarcoma cells. We found miR-329-3p was significantly downregulated in osteosarcoma tissues compared with normal bone tissues. Overexpression of miR-329-3p suppressed osteosarcoma cell proliferation. Moreover, we observed low-toxic cisplatin treatments suppressed miR-329-3p but higher concentrations of cisplatin-induced miR-329-3p expression. In addition, miR-329-3p was significantly downregulated in cisplatin-resistant Saos-2 cells which displayed elevated glucose metabolism. Overexpression of miR-329-3p significantly impaired glucose metabolism of Saos-2 cells. Bioinformatics analysis and luciferase assay consistently demonstrated the glycolysis enzyme, lactate dehydrogenase-A (LDHA) was a direct target of miR-329-3p in osteosarcoma cells. Rescue experiments revealed restoration of LDHA in miR-329-3p-overexpressed cisplatin-resistant cells effectively recovered glucose metabolism, resulting in increased cisplatin resistance. This study demonstrates a miR-329-3p-LDHA-glucose metabolism-cisplatin resistance axis in osteosarcoma cells, providing a miRNA-based therapeutic strategy against chemoresistant osteosarcoma.

The effects of m 6A modification in central nervous system function and disease.

N 6-methyladenosine (m 6A) is an important RNA modification, which is highly active in brain tissues, participates in global intracellular mRNA metabolism, and regulates gene expression and a variety of biological processes. Stable m 6A modification contributes to the normal embryonic brain development and memory formation and plays an important role in maintaining the functions of the central nervous system. However, changes in the level of m 6A modification and the expression of its related proteins cause abnormal nervous system functions, including brain tissue development retardation, axon regeneration disorders, memory changes, and stem cell renewal and differentiation disorders. Recent studies have also found that m 6A modification and its related proteins play key roles in the development of various nervous system diseases, such as Alzheimer's disease, Parkinson's disease, fragile X-chromosome syndrome, depression and glioblastoma. In this review, we summarize the research progresses of m 6A modification regulation mechanism in the central nervous system in recent years, and discusses the effects of gene expression regulation mediated by m 6A modification on the biological functions of the central nervous system and related diseases, thereby providing some insights on the new research targets and treatment directions for the central nervous system diseases.

Tumour necrosis factor-α-induced protein 8-like 2 is a novel regulator of proliferation, migration, and invasion in human rectal adenocarcinoma cells.

Tumour necrosis factor-α-induced protein 8-like 2 (TIPE2) is a tumour suppressor in many types of cancer. However, the mechanism of action of TIPE2 on the growth of rectal adenocarcinoma is unknown. Our results showed that the expression levels of TIPE2 in human rectal adenocarcinoma tissues were higher than those in adjacent non-tumour tissues. Overexpression of TIPE2 reduced the proliferation, migration, and invasion of human rectal adenocarcinoma cells and down-regulation of TIPE2 showed reverse effects. TIPE2 overexpression increased apoptosis through down-regulating the expression levels of Wnt3a, phospho (p)-ß-Catenin, and p-glycogen synthase kinase-3ß in rectal adenocarcinoma cells, however, TIPE2 knockdown exhibited reverse trends. TIPE2 overexpression decreased autophagy by reducing the expression levels of p-Smad2, p-Smad3, and transforming growth factor-beta (TGF-ß) in rectal adenocarcinoma cells, however, TIPE2 knockdown showed opposite effects. Furthermore, TIPE2 overexpression reduced the growth of xenografted human rectal adenocarcinoma, whereas TIPE2 knockdown promoted the growth of rectal adenocarcinoma tumours by modulating angiogenesis. In conclusion, TIPE2 could regulate the proliferation, migration, and invasion of human rectal adenocarcinoma cells through Wnt/ß-Catenin and TGF-ß/Smad2/3 signalling pathways. TIPE2 is a potential therapeutic target for the treatment of rectal adenocarcinoma.

PEST-containing nuclear protein mediates the proliferation, migration, and invasion of human neuroblastoma cells through MAPK and PI3K/AKT/mTOR signaling pathways.

BACKGROUND: PEST-containing nuclear protein (PCNP), a novel nuclear protein, is involved in cell proliferation and tumorigenesis. However, the precise mechanism of action of PCNP in the process of tumor growth has not yet been fully elucidated. METHODS: ShRNA knockdown and overexpression of PCNP were performed in human neuroblastoma cells. Tumorigenic and metastatic effects of PCNP were examined by tumor growth, migration, and invasion assays in vitro, as well as xenograft tumor assay in vivo. RESULTS: PCNP over-expression decreased the proliferation, migration, and invasion of human neuroblastoma cells and down-regulation of PCNP showed reverse effects. PCNP over-expression increased protein expressions of cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, and cleaved poly adenosine diphosphate-ribose polymerase, as well as ratios of B-cell lymphoma-2 (Bcl-2)-associated X protein/Bcl-2 and Bcl-2-associated death promoter/B-cell lymphoma-extra large in human neuroblastoma cells, however PCNP knockdown exhibited reverse trends. PCNP over-expression increased phosphorylations of extracellular signal-regulated protein kinase 1/2, p38, c-Jun N-terminal kinase, as well as decreased phosphorylations of phosphatidylinositol 3-kinase (PI3K), Akt, and mammalian target of rapamycin (mTOR), nevertheless PCNP knockdown exhibited opposite effects. Furthermore, PCNP over-expression significantly reduced the growth of human neuroblastoma xenograft tumors by down-regulating angiogenesis, whereas PCNP knockdown markedly promoted the growth of human neuroblastoma xenograft tumors through up-regulation of angiogenesis. CONCLUSIONS: PCNP mediates the proliferation, migration, and invasion of human neuroblastoma cells through mitogen-activated protein kinase and PI3K/AKT/mTOR signaling pathways, implying that PCNP is a therapeutic target for patients with neuroblastoma.

[The application of CRISPR/Cas9 genome editing technology in cancer research].

The CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease) genome editing technology has become more and more popular in gene editing because of its simple design and easy operation. Using the CRISPR/Cas9 system, researchers can perform site-directed genome modification at the base level. Moreover, it has been widely used in genome editing in multiple species and related cancer research. In this review, we summarize the application of the CRISPR/Cas9 system in cancer research based on the latest research progresses as well as our understanding of cancer research and genome editing techniques.

Inhibition of EGFR-induced glucose metabolism sensitizes chondrosarcoma cells to cisplatin.

Chondrosarcomas are malignant cartilage-forming tumors which are resistant to conventional chemotherapy and radiotherapy. By searching in Oncomine which is a cancer microarray database and web-based data mining platform, we found Glut1 and LDHA were upregulated in human chondrosarcoma patient samples. In this study, we reported total epidermal growth factor receptor (EGFR) expression and phosphorylated EGFR were highly activated in human chondrosarcoma cell lines. In addition, overexpression of EGFR contributed to cisplatin resistance. EGFR promoted glucose metabolism of chondrosarcoma cells through the upregulation of glycolysis key enzymes. Interestingly, cisplatin-resistant chondrosarcoma cells showed upregulated glucose metabolism and EGFR signaling pathway. Finally, we demonstrated that the combination of either EGFR inhibitor or anaerobic glycolysis inhibitor with cisplatin showed synergistically inhibitory effects on cisplatin-resistant chondrosarcoma cells through the inducements of apoptosis and cell cycle arrest. Our project proposed a novel function of EGFR in the regulation of glucose metabolism in chondrosarcoma cells and contributed to the development of therapeutic strategies for the clinical treatment of chondrosarcoma patient.

Clinical characteristics of sudden hearing loss during pregnancy.

Objective: The objective of this study was to explore the clinical characteristics and management of sudden hearing loss (HL) during pregnancy, thus better guiding the clinical practice. Methods: The clinical and follow-up data of 17 patients (17 ears) with sudden HL during pregnancy were analyzed retrospectively (the observe group). Twelve nonpregnant female patients (12 ears) with sudden HL of similar clinical characteristics were selected as the control group. The prognosis of the two groups was compared. All the patients were followed up after delivery, and two of them were readmitted to the hospital 1-2 months after delivery. Results: The observe group had better improvement in hearing and a higher response rate compared to the control group. The pure tone hearing and speech recognition rate of patients could still be improved after the readmitted treatment, and the hearing could partially recover spontaneously during follow-up. The laboratory indicators that affect the inflammatory response and coagulation pathway were significantly different between the two groups. Conclusions: The hearing condition of sudden HL during pregnancy is severe, and the prognosis of these patients is better than nonpregnant patients of similar clinical characteristics. Postpartum treatment is still effective, and some patients showed self-healing with time during follow-up. The inflammatory response and coagulation function may affect the hearing of patients through a metabolic pathway.

The Emerging Roles of Hydrogen Sulfide in Ferroptosis.

Significance: Ferroptosis, a form of regulated cell death characterized by a large amount of lipid peroxidation-mediated membrane damage, joins the evolution of multisystem diseases, for instance, neurodegenerative diseases, chronic obstructive pulmonary disease, acute respiratory distress syndrome, osteoporosis, osteoarthritis, and so forth. Since being identified as the third gasotransmitter in living organisms, the intricate role of hydrogen sulfide (H2S) in ferroptosis has emerged at the forefront of research. Recent Advances: Novel targets in the relevant metabolic pathways have been found, including transferrin receptor 1, cystine/glutamate antiporter, and others, coupled with the exploration of new signaling pathways, particularly the p53 signaling pathway, the nitric oxide/nuclear factor erythroid 2-related factor 2 signaling pathway, and so on. Many diseases such as emphysema and airway inflammation, myocardial diseases, endothelial dysfunction in aging arteries, and traumatic brain injury have recently been found to be alleviated directly by H2S inhibition of ferroptosis. Safe, effective, and tolerable novel H2S donors have been developed and have shown promising results in phase I clinical trials. Critical Issues: Complicated cross talk between the ferroptosis signaling pathway and oncogenic factors results in the risk of cancer when inhibiting ferroptosis. Notably, targeted delivery of H2S is still a challenging task. Future Directions: Discovering more reliable and stable novel H2S donors and achieving their targeted delivery will enable further clinical trials for diseases associated with ferroptosis inhibition by H2S, determining their safety, efficacy, and tolerance.

Increased expression of ABCB6 enhances protoporphyrin IX accumulation and photodynamic effect in human glioma.

BACKGROUND: Glioma recurrence usually occurs close to the tumor resection margins as a result of residual infiltrating glioma cells. 5-aminolevulinic acid (ALA) fluorescence-guided resection of gliomas has been demonstrated to enhance discrimination of tumor tissue and to improve survival. ALA-based photodynamic therapy is an effective albeit still experimental adjuvant treatment option for gliomas. However, insufficient protoporphyrin IX (PpIX) accumulation may limit the benefits of fluorescence-guided resection and photodynamic therapy. METHODS: We investigated the expression of the ATP-binding cassette transporter ABCB6, which regulates porphyrin synthesis, in surgical specimens from human gliomas and manipulated ABCB6 in human glioma cell lines. RESULTS: Our findings demonstrated that expression levels of ABCB6 were greatly elevated in human gliomas compared with normal brain tissues and correlated with World Health Organization histologic grade. A previously undescribed finding was that ABCB6 mRNA expression in solidly fluorescing tumor tissues was higher than that in vaguely fluorescing tumors, suggesting that ABCB6 may be at least in part responsible for PpIX accumulation in glioma cells. Accordingly, ABCB6 overexpression in glioma cell lines caused a marked increase in intracellular levels of PpIX, and was more sensitive to ALA-induced photodynamic therapy-events that could be prevented by silencing ABCB6 via siRNA treatment. CONCLUSIONS: Our findings indicate a crucial role of ABCB6 in ALA metabolism and accumulation of PpIX in glioma. ABCB6 overexpression is a potential approach to enhance accumulation of PpIX for optimizing the subjective discrimination of vague fluorescence and improving the efficacy of ALA-based photodynamic therapy.

[Clinical and prognostic analyses of juvenile sudden sensorineural hearing loss].

OBJECTIVE: To explore the clinical profiles of juvenile sudden sensorineural hearing loss (JSSNHL) and examine its clinical characteristics and prognosis. METHODS: A retrospective review was conducted for the clinical symptoms, audiological characteristics, hematological indices and prognosis in JSSNHL during the past 2 years (from June 2008 to November 2010). All patients were divided into 2 groups according to age, that is group childhood (A, 0-12 years old) and group adolescence (B, 13-18 years old). RESULTS: JSSNHL patients were rarely associated with "aural fullness" symptoms. Two groups of patients with "tinnitus" symptom accounted for 88.2% and 89.5%. Those with "vertigo" symptom accounted for 47.1% and 44.4% respectively. Most patients (81.6%) showed severe and profound hearing loss. The most common types of audiometric curve were flat and total deafness. Some obvious differences existed between two groups in hematological indices, such as platelet count, concentrations of electrolyte ions, mean corpuscular volume and mean corpuscular hemoglobin. Almost half of them (42.1%) improved hearing level during systemic medical treatment. The patients of two groups showed no significant difference in efficacies. And the hearing enhancement degree of patients in group B was more apparent than that of group A. CONCLUSIONS: JSSNHL has different clinical features in different age groups. And the outcomes of personalized treatment regimens may be further improved through classification and grading.

Chlorpyrifos exposure reduces reproductive capacity owing to a damaging effect on gametogenesis in the nematode Caenorhabditis elegans.

Previous studies have revealed that chlorpyrifos exposure adversely affects the reproductive capacity of male rodents. The present study investigated the reproductive toxicity of chlorpyrifos exposure and possible related mechanisms using the nematode Caenorhabditis elegans. L4 nematode larvae were exposed to chlorpyrifos at concentrations of 0.003, 0.03, 0.3 and 3.0 mg l(-1) for different durations. In addition to decreased brood size, reduced spermatid size, increased percentage of abnormal spermatids, suppressed spermatid activation and motility of sperm, damaged oocyte morphology, increased numbers of apoptotic cells and unfertilized oocytes were observed in nematodes exposed to various concentrations of chlorpyrifos. Moreover, expression patterns of the genes spe-10, spe-15, fer-1, prg-1, glp-1, mlh-1, cyb-3, ced-3, ced-4 and ced-9 (which are associated with spermatid size, spermatid activation and morphology, oocyte morphology, oocyte function, and apoptosis) were altered after chlorpyrifos exposure. Therefore, chlorpyrifos exposure may adversely affect fertility in nematodes by influencing both spermatogenesis and oogenesis. Alterations in the expression patterns of genes involved in gametogenesis may explain the corresponding changes in gametogenesis in nematodes exposed to chlorpyrifos. Hence, the model organism Caenorhabditis elegans is recommended for assessment of reproductive toxicity relating to gametogenesis.

[Follow-up of pediatric inflammatory bowel disease].

OBJECTIVE: To analyze the clinical characteristics and prognosis of pediatric inflammatory bowel disease (IBD) through a long-term follow-up so as to improve the diagnosis and management of IBD in children. METHODS: Seventy-three IBD patients admitted into our hospital from May 2000 to September 2010 were re-evaluated with the uniform diagnostic criteria proposed by the 2010 consensus diagnostic criteria for pediatric IBD. All patients were followed up by questionnaire, telephone and face-to-face interview. RESULTS: Among them, 56 cases (76.7%) (ulcerative colitis (UC): n = 34, Crohn's disease (CD): n = 22) were available for follow-up study. Among 34 UC cases, 13 cases had their diagnosis confirmed and 21 cases were diagnosed as probable UC. Meanwhile, among 22 CD cases, 14 and 8 had definite and probable diagnoses respectively. At diagnosis, 46.9% (15/32) of UC patients had extensive colitis, 40.6% (13/32) left-sided colitis while 72.7% (16/22) of CD patients with had ileocolonic. And 28 cases (82.4%) of UC patients and 20 cases (90.9%) of CD patients fulfilled the criteria for moderate to severe grade. Among 56 IBD cases, there was no death for CD, but 5 died for UC (14.7%). In the remaining 29 UC and 22 CD patients, 16 cases (55.2%) and 15 cases (68.2%) stayed symptom-free (P > 0.05). Moreover, 8 cases (27.6%) of UC and 3 cases (13.6%) of CD patients belonged to chronic relapsing type while 16 cases (55.2%) of UC and 15 cases (68.2%) of CD patients were of chronic persistent type. The physical activities of most IBD patients (n = 49) were unrestricted. The surgical rate for IBD was 19.6% (n = 11), 8.8% for UC (n = 3) and 36.4% for CD (n = 8) (P < 0.05). The incidences of surgical complications such as intestinal obstruction, intestinal perforation and hemorrhage of gastrointestinal tract were 7.1% (n = 4), 7.1% (n = 4) and 1.8% (n = 1). And it was more common in the CD group. CONCLUSIONS: Most IBD patients belong to chronic persistent type and then chronic relapsing type. Their physical activities are unrestricted. The surgical rate for CD is significantly higher than UC. And surgical complications such as intestinal obstruction, intestinal perforation and hemorrhage of gastrointestinal tract occur more frequently in the CD group.

PCNP is a novel regulator of proliferation, migration, and invasion in human thyroid cancer.

Thyroid cancer (TC) has increased globally, with a prominent increase in small, papillary thyroid cancers. PEST-containing nuclear protein (PCNP), a nuclear protein, has been found to be associated with human cancers in recent years. However, the role and molecular mechanism of PCNP in thyroid cancer remain underexplored. In the present study, the results showed that the expression levels of PCNP in human thyroid tissues were higher than those in adjacent non-tumor tissues. Overexpression of PCNP reduced the proliferation, migration, and invasion of human thyroid cancer cells and down-regulation of PCNP showed reverse effects. In addition, PCNP regulated cell cycle arrest through modifications in the expression of cell cycle regulating genes and PCNP affected apoptosis via activation of ERK/JNK/p38 pathway in thyroid cancer cells. Moreover, PCNP overexpression promoted autophagy by reducing the expression levels of Wnt/ß-catenin pathway in TC cells, however, PCNP knockdown had opposite effects. Furthermore, PCNP overexpression reduced the growth of xenografted human thyroid cancer, whereas PCNP knockdown showed opposite trends. In conclusion, in vitro and in vivo data demonstrate that PCNP as a tumor suppressor gene may serve as a novel prognostic and potential therapeutic marker in human thyroid cancer.

ER stress mediated­autophagy contributes to neurological dysfunction in traumatic brain injury via the ATF6 UPR signaling pathway.

A major public health problem, traumatic brain injury (TBI) can cause severe neurological impairment. Although autophagy is closely associated with the pathogenesis of TBI, the role of autophagy in neurological deficits is unclear. The purpose of the present study was to investigate the molecular mechanisms of endoplasmic reticulum (ER) stress­induced autophagy and its detrimental effects on neurological outcomes following TBI. A rat model of TBI was established by controlled cortical impact. ER stress activation, autophagy induction and autophagic flux dysfunction were examined in the damaged hippocampus post­TBI. Pharmacological inhibition of ER stress significantly blocked post­traumatic autophagy activation, as evidenced by decreased conversion of microtubule­associated protein 1 light chain 3 (LC3)­I to LC3­II and Beclin­1 expression levels in the hippocampus region. Short hairpin RNA­mediated activating transcription factor 6 knockdown significantly prevented ER stress­mediated autophagy stimulation via targeting essential autophagic genes, including autophagy related (ATG)3, ATG9 and ATG12. Furthermore, neurological scores, foot fault test and Morris water maze were used to evaluate the neurological functions of TBI rats. The results revealed that the blockage of ER stress or autophagy attenuated TBI­induced traumatic damage and functional outcomes. In conclusion, these findings provided new insights into the molecular mechanisms of ER stress­induced autophagy and demonstrated its potential role in neurological deficiency following TBI.

Genetic Susceptibility Study of Chinese Sudden Sensorineural Hearing Loss Patients with Vertigo.

OBJECTIVE: To investigate the genetic causes of sudden sensorineural hearing loss (SSNHL) patients in China. This study focused on analyzing variations of coding sequence of common genes related to deafness, revealing the molecular pathogenesis of sudden deafness from a genomics perspective, discovering molecular markers associated with the onset of deafness, and then supplying prevention to high-risk populations, classifying disease according to accurate etiology, and choosing a much more precision therapy. METHODS: We retrospectively analyzed the clinical characteristics of 51 patients diagnosed as SSNHL with vertigo treated in the Chinese PLA General Hospital. In this study, mutation screening of 307 nuclear genes and mitochondrial genome responsible for human or mouse deafness was performed on the 51 cases of unilateral sudden deafness patients with vertigo. RESULTS: We identified 51 cases of unilateral sudden deafness, including 2 cases of low-mid frequency hearing impairment, 18 cases of mid-high frequency hearing loss, 11 cases of flat-type hearing loss, and 20 cases of all frequency hearing loss. Among the 51 cases, 8 (15.69%) cases of GJB2 heterozygous variations, 1 (1.96%) case of GJB3 heterozygous variations, 5 (9.8%) cases of SLC26A4 heterozygous variations, 2 (3.92%) cases of COCH heterozygous variations, 14 (27.45%) cases of CDH23 heterozygous variations, 14 (27.45%) cases of OTOF heterozygous variations, 1 (1.96%) case of SLC17A8 heterozygous variations and 2 (3.92%) cases of KCNE1 heterozygous variations. No mtDNA gene variations were identified. CONCLUSION: SSNHL has some relationship with hereditary in Chinese population, but its complex genetic pathogenic mechanisms need further study.

Screening mutations of OTOF gene in Chinese patients with auditory neuropathy, including a familial case of temperature-sensitive auditory neuropathy.

BACKGROUND: Mutations in OTOF gene, encoding otoferlin, cause DFNB9 deafness and non-syndromic auditory neuropathy (AN). The aim of this study is to identify OTOF mutations in Chinese patients with non-syndromic auditory neuropathy. METHODS: 73 unrelated Chinese Han patients with AN, including one case of temperature sensitive non-syndromic auditory neuropathy (TS-NSRAN) and 92 ethnicity-matched controls with normal hearing were screened. Forty-five pairs of PCR primers were designed to amplify all of the exons and their flanking regions of the OTOF gene. The PCR products were sequenced and analyzed for mutation identification. RESULTS: Five novel possibly pathogenic variants (c.1740delC, c.2975_2978delAG, c.1194T>A, c.1780G>A, c.4819C > T) were identified in the group of 73 AN patients, in which two novel mutant alleles (c.2975_2978delAG + c.4819C > T) were identified in one Chinese TS-NSRAN case. Besides, 10 non-pathogenic variants of the OTOF gene were found in AN patients and controls. CONCLUSIONS: Screening revealed that mutations in the OTOF gene account for AN in 4 of 73(5.5%) sporadic AN patients, which shows a lower genetic load of that gene in contrast to the previous studies based on other populations. Notably, we found two novel mutant alleles related to temperature sensitive non-syndromic auditory neuropathy. This mutation screening study further confirms that the OTOF gene contributes to ANs and to TS-NSRAN.

[Effects of GnRH analogues on MAPK pathway in rat Leydig cells].

OBJECTIVE: To investigate the effects of GnRH analogues GnRHa and GnRHant on the MAPK pathway in rat Leydig cells. METHODS: Rat Leydig cells were primarily cultured for 24 hours in vitro and serum-starved for 2 hours, followed by treatment with GnRHa (10(-7) mol/L) or GnRHant (10(-6) mol/L) for 0, 5, 15, 30, 60 and 90 minutes, with the 0 min group as the control. Then the protein levels of phosphorylated ERK (p-ERK) and phosphorylated p38 (p-p38) were detected by Western blot, and that of p-ERK determined by the same means after co-incubation of GnRHa or GnRHant with the PKC inhibitor GF109203X at 1, 5, 10 and 20 micromol/L. RESULTS: After stimulation of the Leydig cells with GnRHa or GnRHant for different times, the protein level of p-p38 showed no significant difference from that of the control group (P > 0.05). Then the Leydig cells were treated with GF109203X at different concentrations for 20 minutes and with addition of GnRHa for another 10 minutes. The level of p-ERK was significantly decreased (P < 0.05) by GF109203X at 10 and 20 micromol/L. Compared with the control, the p-ERK expression was increased by 65% at 15 minutes (P < 0.05) in the GnRHant stimulation group, by 81% (to the peak) at 30 minutes (P < 0.05), began to fall at 60 minutes, and returned to the base level at 90 minutes. The p-ERK level exhibited no significant difference from that of the control (P > 0.05) after treatment of the Leydig cells with different concentrations of GF109203X for 20 minutes and then with GnRHant for 30 minutes. CONCLUSION: The ERK MAPK activation induced by GnRHa depends on the PKC pathway, but not that induced by GnRHant. The p-38 MAPK pathway may not be involved in the effect of GnRH analogues on rat Leydig cells.