[Changes in OCTA-related parameters and their impact on retinal sensitivity after ILM flap inversion surgery in patients with IMH]

Objective: To analyze the changes in optical coherence tomography angiography(OCTA)-related parameters before and after idiopathic macular hole (IMH) internal limiting membrane (ILM) flap inversion surgery and assess their impact on retinal sensitivity. Methods: A retrospective case series study was conducted, collecting clinical data of 30 patients (30 eyes) diagnosed with IMH who underwent vitrectomy combined with ILM flap inversion surgery at Shanxi Eye Hospital, affiliated with Shanxi Medical University, between January 2020 and December 2021. Visual acuity and best-corrected visual acuity were examined preoperatively and at 1, 3, and 6 months postoperatively. Microperimetry measured retinal sensitivity (RS), and OCTA measured retinal thickness (RT) as well as vessel density (VD) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Statistical analysis was performed using t-tests, repeated measures analysis of variance, and Pearson correlation analysis. Results: Thirty patients with IMH (30 eyes) were included, with 3 males (3 eyes) and 27 females (27 eyes). The mean age was (62.5±3.0) years, and the follow-up time was (96.3±1.3) days, with a 100% closure rate of macular holes postoperatively. RT in the macular was significantly lower at 1, 3, and 6 months postoperatively compared to preoperative values (F=46.21, P<0.001). The RT in the upper macular region showed statistically significant differences at different time points (P<0.001). VD in the SCP layer showed no significant differences between the upper and lower macular regions at various time points (F=3.21, P=0.601). VD in the upper region of the DCP layer increased at 1, 3, and 6 months postoperatively (P<0.001). RS in the macular was higher at 1, 3, and 6 months postoperatively compared to preoperative values (F=52.01, P<0.001). RS in the lower macular region increased at 3 and 6 months postoperatively (P<0.001), while in the upper region, it increased only at 6 months postoperatively (P<0.001). There was a positive correlation between RS and RT at 1 and 3 months postoperatively, but not at 6 months postoperatively in the upper macular region (r=0.40, P=0.071). In the lower macular region, there was a positive correlation between RS and RT at 1 and 3 months postoperatively (P<0.001). There was no correlation between RS in the upper macular region at 6 months postoperatively and preoperative RT (r=0.43, P=0.072), but there was a positive correlation with RT at 3 months postoperatively (r=0.58, P=0.041). Conclusions: After idiopathic macular hole internal limiting membrane flap inversion surgery, the OCTA-related parameters have changed. There are transient changes in deep vascular parameters and thinning of the retinal layers at the ILM inversion site, leading to decreased sensitivity.

[A case-control study on the relationship between DNA methylation and occupational noise hearing loss]

Objective: To explore the relationship between DNA methylation and occupational noise-induced hearing loss. Methods: A case-control study was conducted. People with hearing loss induced by occupational noise were recruited as the case group and those with normal hearing but still exposed to occupational noise were recruited as the control group. A total of 60 participants were included, of which 30 participants were in the case group and 30 in the control group. The methylation level was detected by 850k genome-wide DNA methylation chip technology. The significance of differential methylated position (DMP) was tested by R-packet 'Champ'. The differential methylated region (DMR) was analyzed by using Champ's Bumphunter algorithm. Cluster profiler was used to analyze the gene list for GO and KEGG pathway enrichment. Results: There was significant difference between two groups in binaural high-frequency average hearing threshold (P<0.05), but there was no significant difference in age, smoking, drinking, hypertension, physical exercise and cumulative noise exposure. The results of DMP and DMR analysis showed that 713875 sites were detected in the case group and the control group, and 439 methylation sites with significant difference, accounting for 0.06%; 650 regions were detected, and 72 methylation regions with significant differences, accounting for 11.08%. Compared with the control group, the results of GO enrichment analysis showed that the case group had statistically significant differences in four pathways: axogenesis of projection neurons in the central nervous system, neuronal development in the central nervous system, axogenesis of neurons in the central nervous system and neuronal differentiation in the central nervous system. KEGG enrichment analysis showed that there were significant differences in sphingolipid metabolism, aldosterone synthesis and secretion, primary bile acid biosynthesis pathway between the case group and the control group. Conclusion: The occurrence of occupational noise-induced hearing loss may be related to the regulation of gene expression related to axogenesis of projection neurons in the central nervous system, development of neurons in the central nervous system, axogenesis of neurons in the central nervous system, differentiation of neurons in the central nervous system, sphingolipid metabolism, aldosterone synthesis and secretion, primary bile acid biosynthesis and gene methylation related to metabolism.

[Effects of unsafe sexual behavior and sexual orientation on previous HIV testing and HIV testing willingness among college students in Harbin]

Objective: To analyze the effects of unsafe sexual behavior and sexual orientation on previous HIV testing and HIV testing willingness among college students in Harbin, to provide a theoretical basis for promoting and promoting HIV testing among them. Methods: A cross-sectional survey design was used to place the automatic vending machine of HIV urine test kit in 9 universities in Harbin from December 2017 to January 2018. The questionnaire star was used to design and recruit college students to carry out an anonymous online survey. The estimated sample size was 6 659. A multivariate logistic regression model was used to analyze the effects of unsafe sexual behavior and sexual orientation on previous HIV testing and HIV testing willingness among college students. WPS 2016 was used to sort out the database, and SPSS 21.0 software was used for statistical analysis. Results: A total of 60 849 valid questionnaires were collected. 19.1% (11 189/58 605) of college students reported having sex. College students who used condoms correctly every time, occasionally or never during sex in the past six months 58.5% (6 206/10 603), 25.2%(2 669/10 603)and 16.3% (1 728/10 603), respectively. Heterosexuality, homosexuality and bisexuality accounted for 94.1% (54 393/57 823), 2.4% (1 369/57 823) and 3.5% (2 061/57 823), respectively. The HIV testing willingness of college students was 73.3% (44 572/60 849). The proportion of previous HIV testing was 10.3% (951/9 241). Results of the multivariate logistic analysis showed that compared with the college students who used condoms correctly whenever they had sex in the past six months, there was no significant difference in the proportion of previous HIV testing among college students who sometimes/occasionally used or never used condoms (OR=0.94,95%CI:0.69-1.29; OR=1.11,95%CI:0.73-1.67), but their willingness to HIV testing was lower (OR=0.79, 95%CI:0.71-0.89; OR=0.48, 95%CI:0.42-0.55); Compared with heterosexual college students, homosexual or bisexual college students have a higher proportion of previous HIV testing (OR=2.62, 95%CI:1.62-4.24; OR=2.04, 95%CI:1.25-3.32), but have lower HIV testing willingness (OR=0.76, 95%CI: 0.62-0.93; OR=0.64, 95%CI: 0.53-0.77). Conclusions: Unsafe sexual behavior existed among college students in Harbin, and college students with weak awareness of HIV prevention also have weak awareness of testing. Behavioral intervention should be strengthened and HIV testing promoted. Compared with heterosexuals, homosexual or bisexual college students had a higher proportion of previous HIV testing, but their willingness to test was lower. The HIV detection mode with better concealment, accuracy, and convenience should be promoted on the college's campus.

[Analysis of the level of T lymphocyte subsets and the relationship with the prognosis of pulmonary fibrosis in patients with paraquat poisoning]

Objective: To analyze the levels of T lymphocyte subsets (CD3, CD4, CD8 and CD4/CD8) in patients with paraquat poisoning, and to explore the relationship between the changes of T lymphocyte subsets and the prognosis of pulmonary fibrosis. Methods: In October 2019, a total of 47 patients with oral 20% paraquat low water solvent poisoning in Guangzhou 12th people's Hospital from June 2018 to June 2019 were selected as the research objects. Patients were divided into early death group (16 cases died within 2 weeks) and non early death group (31 cases survived more than 2 weeks) . The non early death group was divided into pulmonary fibrosis group (23 cases) and normal lung group (8 cases) . 20 healthy people in the same period were randomly selected as the control group. The neutrophils (N) , C reaction protein (CRP) , alanine aminotransferase (ALT) , creatinine (Cr) , amylase (aAMY) , creatine kinase isoenzyme (CKMB) , pH, HCO(3)(-), blood oxygen saturation (SO(2)) and lactic acid (Lac) of patients poisoned within 3 d were examined every day. Independent sample t-test was used for inter group comparison, and paired sample t-test was used for intra group comparison. Results: Compared with non early death group, the levels of N, CRP, ALT, Cr, aAMY, CKMB and Lac in early death group increased (P<0.05) , while pH and HCO(3)(-) decreased (P<0.05) . Compared with the control group, the levels of CD3, CD4 and CD4/CD8 were decreased on the first day in the early death group and non early death group (P<0.05) , and the levels of CD3, CD4 and CD4/CD8 were decreased on the 15th day in the pulmonary fibrosis group (P<0.05) . Compared with the normal lung group, the levels of CD3, CD4 and CD4/CD8 in the pulmonary fibrosis group decreased on the 15th day (P<0.05) . Conclusion: The persistent low cellular immune function in patients with paraquat poisoning is related to the progress of pulmonary fibrosis, which is an important factor affecting the prognosis of patients with pulmonary fibrosis.

[ABO gene subtypes and gene expression analysis in three cases of hematological malignancies patients]

Objective: To explore the application and discovery of genotyping, gene sequencing, and gene expression analysis in the determination of ABO blood group subtypes and antigen expression abnormalities in hematological malignancies patients. Methods: From June 2019 to May 2020, three clinical cases were found with forward and reverse ABO typing discrepancy or atypical serologic agglutination pattern in the laboratory and blood transfusion department of Hebei Yanda Ludaopei Hospital were selected. Sequence-specific primer PCR (PCR-SSP) and Sanger sequencing of ABO gene coding regions were performed to determine the ABO genotypes, and whole transcriptome sequencing was used to analyze ABO and FUT1 gene expression levels. Results: A 12-year-old female acute lymphoblastic leukemia patient was determined as O.01.02 and BA.04 sub-genotype, corresponding to the serological B(A) subtype, and her ABO gene expression was normal (354.80). A 41-year-old female acute myeloid leukemia patient was determined as A1.02 and B.01 genotype, corresponding to the serological A(1)B phenotype, and her ABO gene expression was significantly reduced (45.70). A 42-year-old male with myelodysplastic syndrome and myelofibrosis was determined as A1.02 and A2.05 sub-genotype, corresponding to the serological A(1) and A(2) phenotype, respectively, and his ABO expression was negative. FUT1 expression was in the normal range in all three cases. The clinical blood product infusion strategy was formulated according to the genotype and the corresponding immunological subtype, and no significant transfusion-related adverse reactions occurred. Conclusion: Blood group sub-genotypes or aberrant gene expression can lead to ambiguities in serological blood group determination in hematological malignancies patients. ABO genotyping and gene expression analysis can help in this scenario and escort blood product infusion safety.

[Effects and mechanism of mitochondrial transcription factor A and cytochrome c oxidase pathway in the energy production of hypoxic cardiomyocytes of rats regulated by tumor necrosis factor receptor associated protein 1]

Objective: To investigate the effects and mechanism of mitochondrial transcription factor A (TFAM) and cytochrome c oxidase (COX) pathway in the energy production of hypoxic cardiomyocytes of rats regulated by tumor necrosis factor receptor associated protein 1 (TRAP1). Methods: The cardiomyocytes were isolated from 135 neonatal Sprague-Dawley rats (aged 1-3 d) and cultured for the following experiments. (1) Cells were collected and divided into normoxia blank control (NBC) group, hypoxia blank control (HBC) group, hypoxia+ TRAP1 over-expression control (HTOC) group, and hypoxia+ TRAP1 over-expression (HTO) group according to the random number table (the same grouping method below), with 1 bottle in each group. Cells in NBC group were cultured routinely, cells in HBC group were cultured in hypoxic condition for 6 hours after routine culture, cells in HTOC and HTO groups were respectively added with TRAP1 over-expression empty virus vector and TRAP1 over-expression adenovirus vector virus suspension for transfection for 48 hours after routine culture and then cultured in hypoxic condition for 6 hours. The protein expression of TFAM of cells in each group was detected by Western blotting. (2) Cells were collected and divided into NBC, HBC, HTOC, HTO, HTO+ TFAM interference control (HTOTIC), and HTO+ TFAM interference (HTOTI) groups, with 1 well in each group. Cells in the former 4 groups were dealt with the same methods as the corresponding groups in experiment (1). Cells in HTOTIC and HTOTI groups were respectively added with TFAM interference empty virus vector and TFAM interference adenovirus vector virus suspension for transfection for 48 hours, and the other processing methods were the same as those in HTO group. The content of ATP of cells in each group was determined by ATP determination kit and microplate reader, and the COX activity of cells in each group was determined by COX activity assay kit and microplate reader. (3) Cells were collected and divided into NBC group, normoxia+ sodium azide (NSA) group, HBC group, and hypoxia+ sodium azide (HSA) group, with 1 well in each group. Cells in NBC and HBC groups were respectively dealt with the same methods as the corresponding groups in experiment (1). Cells in NSA and HSA groups were respectively added with 32 nmol sodium azide at 30 min before experiment or hypoxia, and then cells in HSA group were cultured in hypoxic condition for 6 hours. The content of ATP was determined by the same method as above. The above three experiments were repeated for three times. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: (1) Compared with that in NBC group, the protein expression of TFAM of cells in HBC group was significantly decreased (P<0.01). Compared with that in HBC group or HTOC group, the protein expression of TFAM of cells in HTO group was significantly increased (P<0.01). (2) Compared with 0.552±0.041 and 1.99±0.15 in NBC group, the COX activity (0.270±0.044) and ATP content (1.09±0.11) of cells in HBC group were significantly decreased (P<0.01). Compared with 0.269±0.042 and 1.17±0.12 in HBC group and those in HTOC group, the COX activity (0.412±0.032 and 0.404±0.016) and ATP content (1.75±0.06 and 1.69±0.07) of cells in HTO and HTOTIC groups were significantly increased (P<0.01). Compared with those in HTO and HTOTIC groups, the COX activity (0.261±0.036) and ATP content (1.23±0.07) of cells in HTOTI group were significantly decreased (P<0.01). (3) Compared with that in NBC group, the ATP content of cells in NSA and NBC groups was significantly decreased (P<0.01). Compared with that in HBC group, the ATP content of cells in HSA group was significantly decreased (P<0.01). Conclusions: TRAP1 can increase the COX activity of cardiomyocytes by raising the expression of TFAM, and finally alleviate the impairment in energy production of cardiomyocytes caused by hypoxia.

[Association between GSTP1 gene polymorphisms and susceptibility to noise-induced hearing loss]

Objective: To investigate the association between the single nucleotide polymorphisms (SNPS) at rs1695 and rs6591256 in glutathione S-transferase P1 (GSTP1) gene and susceptibility to noise-induced hearing loss in Chinese Han workers exposed to noise. Methods: Using the 1: 1 nested case-control study and taking 6297 workers exposed to noise in a steel plant in Henan province as the cohort study population in July 2019, we screened those who have been exposed to noise for ≥3 years and whose binaural high frequency (3000, 4000, 6000 Hz) average hearing threshold is ≥40 dB (A) into the case group. The control group was selected according to the matching criteria of the same sex, same type of work, and the age difference was not more than 5 years old, and the working age difference was not more than 2 years. 276 subjects were selected into the case group and the control group respectively. The medium and high throughout single nucleotide polymorphism typing technology (SNPscanTM technology) was used to detect the polymorphism of three nucleotide sites of GSR gene, and conditional logistic regression was used to analyze the relationship between single nucleotide polymorphism (SNP) and NIHL, and the relationship between different polymorphic sites and the risk of NIHL after adjusting covariates. After stratification with different cumulative noise exposure (CNE) , Conditional logistic regression analysis was used to analysis the risk of NIHL at different loci. Results: The mean and standard deviation of age of the selected subjects was (40.28±8.00) , the mean and standard deviation of noise-exposed working years was (18.7±8.92) years. The range of noise exposure levels and comulative noise exposure were 80.05-93.35dB (A) and 86.83-107.92 dB (A) ·year, respectively. Compared with the control group, there were no statistically significant differences in age, noise-exposured working years, intensity of noise exposure, CNE, gender, drinking, hypertension prevalence and noise exposure level in the hearing loss group (P>0.05) , while there were statistically difference in smoking, binaural high-frequency average hearing threshold and binaural speech frequency (P<0.05) . After adjusting for smoking, drinking, hypertension and other factors, in the co-dominant model, compared with GGgenotype, the risk of NIHL was higher in rs1002149 GT genotype and rs2251780 GA genotype (OR=1.558, 95%CI: 1.028-2.361; OR=1.550, 95%CI: 1.020-2.355, P<0.05) ; compared with TT/GT genotype, the rs1002149 TT genotype has a higher risk of developing NIHL (OR=1.494, 95%CI: 1.002-2.228, P<0.05) , while rs3779647 genotype had no relationship with the risk of NIHL (P>0.05) . In the equivalent sound level (L(Aeq)) of noise >85 dB (A) stratification, compared with GG genotype, carrying rs1002149 GT genotype and rs2251780 GT genotype has higher risk of nihl (OR=1.801, 95%CI: 1.093-2.967; OR=1.720, 95%CI: 1.050-2.817, P<0.05) . Haplotype analysis of two sites, rs1002149 and rs2251780, was not found to be related to NIIHL susceptibility. Conclusion: The allele G of rs1695 and rs6591256 may be risk factors of NIHL.

[The humor characteristics of young epileptic patients and its correlation with depression]

Objective: To explore the characteristics of humor in young adult epileptic patients and examine the relationship between humor and depression. Methods: We recruited 55 young adult epileptic patients who visited outpatient clinic of the Department of Neurology of Yijishan Hospital of Wannan Medical College between October 2018 and March 2019 and 44 healthy controls to complete the multidimensional humor scale (MSHS), humor style questionnaire (HSQ) and Beck depression scale-Ⅱ (BDI-Ⅱ), and compared their differences between the two groups. Results: The results showed that the young adult patients with epilepsy (PWEs) were affected in humor creation, coping with humor and the totally scores of MSHS. The scores of humor creation, coping with humor and the totally scores of MSHS in the young epilepsy patients were 25.3±5.9, 16.7±5.0 and 61±10, which were significantly lower than those in the control group 29.8±6.1, 21.1±2.6 and 71±8. As for the humor style, self-defeating humor scores in PWEs were higher than controls 14±5 vs 9±3, and the self-enhancing humor scores were lower than controls 18±7 vs 23±6. The scores of BDI-Ⅱ in PWEs were significantly higher than those of normal controls 13±7 vs 6±4. Pearson's correlation test showed that the scores of BDI-Ⅱ were negatively correlated with humor creation, coping with humor, the totally scores of MSHS and self-enhancing humor scores (r=-0.566--0.721, P<0.05), while it was positively correlated with self-defeating humor scores (r=0.818, P<0.05). Among the clinically relevant factors, the scores of BDI-Ⅱ were correlated with seizure control and gender. Multiple stepwise linear regression showed that coping with humor, self-defeating and self-enhancing humor scores were closely related with depression in young epileptic adults. Conclusion: The young adults with epilepsy are affected in sense of humor and humor style, which are closely related with depression.

[The impact of KIT and other concomitant gene mutations on the prognoses of patients with core-binding factor acute myeloid leukemia]

Objective: To study the impact of KIT and other concomitant gene mutations on the prognoses of patients with core-binding factor acute myeloid leukemia (CBF-AML). Methods: A total of 104 newly diagnosed patients with CBF-AML in Hebei Yanda Lu Daopei Hospital from January 2014 to February 2018 were analyzed, and high-throughput gene sequencing for the detection of mutations among 58 genes was executed. Also, the clinical features of KIT mutation-positive CBF-AML (KIT+CBF-AML) patients and the effects of other concomitant gene mutations on the prognoses of patients were also analyzed. Results: A total of 56 cases (53.85%) with KIT mutations were found in 104 CBF-AML patients. Among this, KIT D816 mutation was the most common (32 patients), followed by the N822 mutation (17 patients). Patients with KIT+CBF-AML have a higher proportion of bone marrow blasts at the time of diagnoses and are more likely to have sex chromosome loss. Among the 52 patients with KIT+CBF-AML who were followed up, the allogeneic hematopoietic stem cell transplantation (allo-HSCT) group had a higher overall survival rate (OS) than that of the chemotherapy group (88.9% vs 57.1%, χ(2)=6.076, P<0.05). The event-free survival (EFS) and OS of patients with KIT+CBF-AML with FLT3 mutation were both significantly lower than those of the FLT3 mutation-negative group (EFS: 40.0% vs 72.3%, χ(2)=6.557, P<0.05; OS: 60.0% vs 87.2%, χ(2)=8.305, P<0.05). The OS of the patient with TET2 mutation was lower than that of the TET2 mutation-negative group (50.0% vs 87.5%, χ(2)=4.130, P<0.05). Conclusion: Patients with KIT+CBF-AML with concomitant gene mutations, especially FLT3 and TET2, have poor prognoses, which can be improved by allo-HSCT.

[Genetic characteristics and clinical outcomes of pediatric acute myeloid leukemia with NUP98-NSD1 fusion gene]

Objective: To investigate the genetic characteristics and clinical outcomes of pediatric acute myeloid leukemia patients with NUP98-NSD1 fusion gene. Methods: A total of 80 pediatric AML patients were enrolled in this study, and bone marrow specimens were collected at initial diagnosis and relapse. NUP98-NSD1 was screened by fluorescence in situ hybridization (FISH) and PCR. Other laboratory test results and clinical outcomes were further analyzed for the NUP98-NSD1 positive cases. Results: A total of eight patients (10.0%) were positive for NUP98-NSD1, which were all fusions of NUP98 exon12 and NSD1 exon 6. There were two M2, three M4, and three M5 cases according to the French-American-British classification. Seven patients had karyotype results at the time of initial diagnosis, and none of them had complicated karyotype abnormalities. Among these patients, two cases had normal karyotype, three cases had trisomy 8, one case had trisomy 6, and two cases had anomalies involving 9q13 or 9q21. Additional karyotypic abnormalities and clonal evolutions were observed during disease progression or relapse, five cases had 9q13 or 9q32 abnormalities. Five cases (62.5%) were positive with FLT3-ITD mutation. Patients were treated with DAE/NAE/HAE/IA chemotherapy. Three cases did not achieve remission after several courses of chemotherapy, and five cases achieved remission but relapsed in 1 to 19 months. Five cases underwent salvage allogeneic hematopoietic stem cell transplantation (allo-HSCT). Among whom, four died in 40 days to 4 months after transplantation, and one survived 8.5 months till the last follow-up. Conclusions: NUP98-NSD1 is a recurrent genetic abnormality with significant clinical prognostic significance, and this group of disease has unique clinical and genetic characteristics. NUP98-NSD1 should be screened by FISH or PCR for children with AML who are newly diagnosed or refractory and relapsed to identify the high-risk genetic marker.

Parathyroid hormone (1-34) promotes fracture healing in ovariectomized rats with type 2 diabetes mellitus

Ovariectomized (OVX) rats with type 2 diabetes mellitus (T2DM) with femur fracture received vehicle, insulin, or insulin plus parathyroid hormone (PTH) treatment for 2 and 3 weeks. Radiography, histomorphometry, histology, and immunohistochemistry in callus were evaluated.

INTRODUCTION

Reports about effects of PTH plus insulin on callus formation of osteoporotic fracture with T2DM were limited. This study was designed to investigate the effects of the combination of PTH and insulin on fracture healing in OVX rats with T2DM.

METHODS

Two-month-old female rats were randomly divided into five groups: normal fracture (F), OVX fracture (OF), T2DM + OVX fracture (DOF), insulin-treated (2-4 u/daylight, 4-6 u/night, DOFI), and treated with insulin and PTH (50 μg/kg/day, 5 days/week, DOFIP). A closed mid-shaft fracture was established in the right femurs of all rats after 6 weeks of OVX. Rats were euthanized at 2 and 3 weeks post-fracture according to the time schedule, respectively.

RESULTS

The administration of insulin alone or insulin combined with PTH significantly increased mineralized bone volume fraction (BV/TV) and connectivity density (Conn.D) compared with those of the DOF group at 3 weeks post-fracture and also increased cartilaginous callus area ratio in the DOFI and DOFIP groups at 2 weeks and bony callus area ratio in the DOFIP groups at both the 2 and 3 weeks post-fracture.

CONCLUSIONS

OVX rats with T2DM exhibited a marked delay in the fracture healing process; insulin treatment ameliorated these effects, and the healing process was enhanced following treatment with a combination of insulin and PTH.

Combined application of ultrasound and SPECT/CT has incremental value in detecting parathyroid tissue in SHPT patients

PURPOSE

The goal of this study is to investigate whether combined application of ultrasound and 99mTc-sestamibi SPECT/CT had the incremental value in accurately detecting parathyroid tissue in patients with SHPT over either method alone.

PATIENTS AND METHODS

Sixty patients with SHPT on hemodialysis were evaluated preoperatively with parathyroid 99mTc-sestamibi SPECT/CT scintigraphy and ultrasound prior to parathyroidectomy. The sensitivity, specificity and accuracy of 99mTc-sestamibi SPECT/CT scintigraphy, ultrasound and combined application were determined respectively.

RESULTS

The sensitivity, specificity and accuracy of ultrasound were 81% (155/192), 47% (17/36) and 82% (172/228), respectively. The sensitivity, specificity and accuracy of 99mTc-sestamibi SPECT/CT were 85% (163/192), 58% (21/36) and 89% (184/228) respectively. The accuracy of 99mTc-sestamibi SPECT/CT in the diagnosis of parathyroid tissue in patients with SHPT is significantly higher than that of ultrasound. The sensitivity, specificity and accuracy of combined application of ultrasound and 99mTc-sestamibi SPECT/CT were 93% (178/192), 61% (22/36) and 97% (200/228). The sensitivity, specificity and accuracy of combined application of ultrasound and 99mTc-sestamibi SPECT/CT were higher than those of either ultrasound or 99mTc-sestamibi SPECT/CT.

CONCLUSIONS

The combined application of ultrasound and 99mTc-sestamibi SPECT/CT had incremental value in accurately detecting parathyroid tissue in patients with SHPT over either method alone.

Abnormal 5-HT modulation of stress behaviors in the Kv4.2 knockout mouse

The Kv4.2 gene codes for an essential subunit of voltage-gated A-type potassium channels that are involved in dendritic signal integration and synaptic plasticity. Detailed cellular characterization in CA1 pyramidal neurons of the hippocampus has shown that knocking out the Kv4.2 gene increases neuronal excitability and promotes long-term potentiation. However, the overall behavioral consequences of these modifications have not been fully explored. Given the growing connection between neuronal plasticity and affect processing in the hippocampus and other Kv4.2 expressing regions, we proposed to investigate whether the absence of this gene would alter the stress response of mice to the forced swimming and tail suspension tests (TSTs) for depression-like behavior. Kv4.2 knockout (KO) mice, generated in the 129SvEv background, demonstrated elevated immobility and a loss of swimming, as well as antidepressant resistance to the selective 5-HT reuptake inhibitor fluoxetine (FLX). Characterization of a relatively new head movement behavior category, responsive to serotonergic treatment in wildtype (WT) mice, supported conclusions of abnormal 5-HT modulation. Electrophysiology recordings in the prefrontal cortex showed a blunting of postsynaptic response to direct 5-HT application following a single period of swim stress only in the animals without the Kv4.2 subunit. Based on our findings, we hypothesize that Kv4.2 KO mice may have an exaggerated 5-HT response to stress leading to a premature desensitization of postsynaptic receptors and a loss of continued behavior modulation. These results may shed some light on the involvement of A-type potassium channels in the effective action of selective serotonin reuptake inhibitor (SSRI) antidepressants.

Searching for molecules mediating glial-neuronal communication

The newly identified axotactin (AXO) protein in Drosophila, a member of the neurexin superfamily, appears to be a key element that mediates the effects of glial cells on neuronal membrane excitability and synaptic plasticity.

A glial-neuronal signaling pathway revealed by mutations in a neurexin-related protein

In the nervous system, glial cells greatly outnumber neurons but the full extent of their role in determining neural activity remains unknown. Here the axotactin (axo) gene of Drosophila was shown to encode a member of the neurexin protein superfamily secreted by glia and subsequently localized to axonal tracts. Null mutations of axo caused temperature-sensitive paralysis and a corresponding blockade of axonal conduction. Thus, the AXO protein appears to be a component of a glial-neuronal signaling mechanism that helps to determine the membrane electrical properties of target axons.