Variations in the NMDA receptor subunit 2B gene (GRIN2B) and schizophrenia: a case-control study.

A well established model for the pathophysiology of schizophrenia postulates a role for the NMDA-mediated glutamate transmission. The human gene coding for the 2B subunit of the NMDA receptor (GRIN2B) is considered a candidate based on its selective expression in brain. To evaluate the hypothesis that GRIN2B acts as a major gene in determining susceptibility to schizophrenia, a case-control association study was performed. Five single nucleotide polymorphisms (SNPs) were genotyped in 188 Italian patients and 156 control subjects. The association study showed a marginally significant excess of homozygosity for the polymorphism located in the 3'UTR region (P = 0.04). No other difference in genotype and allele frequencies was found in schizophrenics as compared to the control series. The case-control study was also carried out on estimated haplotypes, confirming a trend for association (P = 0.04). These results suggest that GRIN2B variations might be linked with susceptibility to schizophrenia. Replication studies on larger samples are warranted to further test this hypothesis.     

Deep spatial profiling of human COVID-19 brains reveals neuroinflammation with distinct microanatomical microglia-T-cell interactions

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Development and characterization of a new monoclonal antibody against SARS-CoV-2 NSP12 (RdRp)

SARS-CoV-2 NSP12, the viral RNA-dependent RNA polymerase (RdRp), is required for viral replication and is a therapeutic target to treat COVID-19. To facilitate research on SARS-CoV-2 NSP12 protein, we developed a rat monoclonal antibody (CM12.1) against the NSP12 N-terminus that can facilitate functional studies. Immunoblotting and immunofluorescence assay (IFA) confirmed the specific detection of NSP12 protein by this antibody for cells overexpressing the protein. Although NSP12 is generated from the ORF1ab polyprotein, IFA of human autopsy COVID-19 lung samples revealed NSP12 expression in only a small fraction of lung cells including goblet, club-like, vascular endothelial cells, and a range of immune cells, despite wide-spread tissue expression of spike protein antigen. Similar studies using in vitro infection also generated scant protein detection in cells with established virus replication. These results suggest that NSP12 may have diminished steady-state expression or extensive posttranslation modifications that limit antibody reactivity during SARS-CoV-2 replication.     

Expression of nuclear insulin receptor substrate 1 in breast cancer

BACKGROUND: Insulin receptor substrate 1 (IRS-1), a cytoplasmic protein transmitting signals from the insulin and insulin-like growth factor 1 receptors, has been implicated in breast cancer. Previously, it was reported that IRS-1 can be translocated to the nucleus and modulate oestrogen receptor alpha (ERalpha) activity in vitro. However, the expression of nuclear IRS-1 in breast cancer biopsy specimens has never been examined. AIMS: To assess whether nuclear IRS-1 is present in breast cancer and non-cancer mammary epithelium, and whether it correlates with other markers, especially ERalpha. Parallel studies were carried out for the expression of cytoplasmatic IRS-1. METHODS: IRS-1 and ERalpha expression was assessed by immunohistochemical analysis. Data were evaluated using Pearson's correlation, linear regression and receiver operating characteristic analysis. RESULTS: Median nuclear IRS-1 expression was found to be low in normal mammary epithelial cells (1.6%) and high in benign tumours (20.5%), ductal grade 2 carcinoma (11.0%) and lobular carcinoma (approximately 30%). Median ERalpha expression in normal epithelium, benign tumours, ductal cancer grade 2 and 3, and lobular cancer grade 2 and 3 were 10.5, 20.5, 65.0, 0.0, 80 and 15%, respectively. Nuclear IRS-1 and ERalpha positively correlated in ductal cancer (p<0.001) and benign tumours (p<0.01), but were not associated in lobular cancer and normal mammary epithelium. In ductal carcinoma, both nuclear IRS-1 and ERalpha negatively correlated with tumour grade, size, mitotic index and lymph node involvement. Cytoplasmic IRS-1 was expressed in all specimens and positively correlated with ERalpha in ductal cancer. CONCLUSIONS: A positive association between nuclear IRS-1 and ERalpha is a characteristic for ductal breast cancer and marks a more differentiated, non-metastatic phenotype.     

Frequency and distribution of trisomy 11 in multiple myeloma patients: relation with overexpression of CCND1 and t(11;14)

Multiple myelomas (MM) recently have been stratified into five groups (TC1-TC5) on the basis of the presence of the recurrent IgH chromosomal translocation and cyclin D expression. Cyclin D1 is detectable in up to one third of MM patients and plays crucial role in the regulation of G1-S transition in cell cycle. To evaluate the mechanisms of cyclin D1 overexpression, fluorescence in situ hybridization analysis with specific probes for the CCND1 gene and t(11;14)(q13;q32) were performed on highly purified plasma cells from bone marrow samples of 30 MM patients at diagnosis. CCND1 gene overexpression was detected in 14/30 cases (46.6%). Patients with evidence of the t(11;14) showed strong nuclear staining for cyclin D1 (TC1 group) and 7/8 demonstrated CCND1 overexpression. The remaining 7/15 cases with increased CCND1 gene copy numbers lacked the t(11;14) and showed low to negative levels of cyclin D1 protein (TC2 group). Trisomy 11 was demonstrated in 2/8 cases carrying the t(11;14) (TC1), 6/7 overexpressing cyclin D1 without the translocation (TC2), and 4/15 negative for both alterations (TC3-TC5). According to our data, trisomy 11 does not appear to directly cause CCND1 gene overexpression because it was present in 4/15 patients without the overexpression of the CCND1 gene and in 2/8 patients carrying the t(11;14). One patient belonging to the TC2 group overexpressed cyclin D1 and lacked both trisomy and translocation, suggesting that cyclin D1 can be dysregulated by additional mechanisms. In the TC2 group, trisomy 11 may probably be considered as a recurrent polisomy of the hyperdiploid status.     

Human respiratory coronavirus HKU1 versus other coronavirus infections in Italian hospitalised patients.

BACKGROUND: Human respiratory coronavirus (hCoV) HKU1 infections were reported for the first time in 2005 in Hong Kong. OBJECTIVE: To investigate epidemiological, clinical, and diagnostic features of HKU1 infections. STUDY DESIGN: Longitudinal, prospective study from November 2005 through May 2006 in a hospitalised patient population. RESULTS: Overall, 48/426 (11.3%) patients were found to be infected by hCoV acute respiratory tract infections (ARTI). Of these, 10 (19.2%) were caused by HKU1 (6 single infections and 4 coinfections) during the period January-May 2006. Diagnosis was made by using RT-PCR for all four hCoVs, and in parallel, in-house developed group-specific monoclonal antibodies (MAbs) for HKU1 and 229E. HKU1-specific MAb was able to retrospectively identify 8 of 10 HKU1 strains detected by RT-PCR. Phylogenetic analysis showed that four HKU1 strains were genotype A and six genotype B. In HKU1-infected patients, the predominant clinical symptom was rhinorrhea (nine patients). Within group II hCoV, HKU1-infected patients had a significantly lower rate of lower ARTI compared to OC43-infected patients. CONCLUSION: HKU1 hCoV strains circulated in northern Italy during the winter-spring season 2005-2006. Both HKU1 genotypes were detected. HKU1-specific MAb may contribute to the rapid diagnosis of HKU1 infections currently performed by RT-PCR.     

Thyrotoxic Periodic Paralysis: A Case Report and Literature Review

We describe a 37-year-old man with a 4-month history of episodic muscular weakness, involving mainly lower-limbs. Hypokalemia was documented in one episode and managed with intravenous potassium chloride. Hyperthyroidism was diagnosed 4 months after onset of attacks because of mild symptoms. The patient was subsequently diagnosed as having thyrotoxic periodic paralysis associated with Graves’ disease. Treatment with propranolol and methimazol was initiated and one year later he remains euthyroid and symptom free. Thyrotoxic periodic paralysis is a rare disorder, especially among Caucasians, but it should always be considered in patients with acute paralysis and hypokalemia, and thyroid function should be evaluated.     

Cytotoxicity and DNA-damage in human lung epithelial cells exposed to respirable alpha-quartz.

Occupational exposure to respirable crystalline silica is associated with the development of silicosis, lung cancer and airways diseases. In order to assess cytotoxic effects and direct-oxidative DNA damage induced by short-term exposure to different doses of respirable alpha-quartz (NIST SRM1878a), we conducted a study using A549 cells. The cells were exposed to alpha-quartz at 25, 50, 100 microg/ml for 4 h and analysed by scanning electron microscope (SEM) and LDH release assay for cytotoxic effect evaluation. Cells were also exposed to 10, 25, 50, 100 microg/ml of alpha-quartz for 2 h and 4 h and analysed by Fpg comet test to evaluate direct and oxidative DNA damage. SEM observations of treated cells showed bleb development at lower doses and alterations of microvilli morphology at the highest dose. A slight LDH release was found only at 100 microg/ml. Fpg comet test showed a dose-related oxidative DNA damage in cells exposed for 2 h to quartz. Cells exposed for 4h at the same concentrations showed a dose-related direct DNA damage and the presence of oxidative DNA damage at lower doses. The bleb induction on cell surface evidenced by SEM at lower doses correlates with the presence of oxidative DNA damage at 4 h. The cell surface modifications observed by SEM at 100 microg/ml indicate that high doses of quartz induce more evident cytotoxic effects confirmed by LDH analysis and correlate with the genotoxicity showed by comet assay.     

Alkaloids,amides and antispasmodic activity of Zanthoxylum hyemale

Two quinoline alkaloids, (-)-R-geilbalansine (1) and hyemaline (2), as well as aromatic amide, N-[2-(3,4-dimethoxyphenyl)-2-methoxyethyl)-2-methoxyethyl]benzamide (O-methylbalsamide) (3), were isolated as new natural products from the stem barks of Zanthoxylum hyemale, together with seven known compounds. Their structures were determined on the basis of spectroscopic data (IR, (1)H- and (13)C-NMR, MS). In addition, the antispasmodic activity of the crude extract of Z. hyemale and three other more abundant isolated compounds (4, 5 and 10) were studied in two different antispasmodic test models on isolated rat ileum and only the crude ethanolic extract presented antispasmodic activity.