Applanation resonance tonometry for intraocular pressure in humans

Glaucoma is a group of diseases associated with optic nerve damage and loss of visual field. The aetiology is not completely understood, but one of the major risk factors is elevated intraocular pressure (IOP). Reliable methods for measuring the IOP are therefore important. The aim of the study was to investigate the ability of the applanation resonance tonometry (ART) system, based on continuous force and area recording, to measure IOP in humans. Both the phase of initial indentation (IOPIndentation) and the phase when the sensor was removed (IOPRemoval) from the cornea were analysed. The Goldmann applanation tonometry (GAT) was used as reference method. The study included 24 healthy volunteers with normal IOP and 24 patients with elevated IOP. The correlation and standard deviation (SD) between IOPIndentation and IOPGAT was R = 0.92 (p < 0.001), SD = 3.6 mmHg, n = 104, and between IOPRemoval and IOPGAT R = 0.94 (p < 0.001), SD = 3.1 mmHg, n = 104. In conclusion, resonance sensor technology has made it possible to introduce a new multi-point method for measuring IOP, and the method is relevant for measuring IOP in humans. The study indicates that with further development towards elimination of position dependence, the ART has the potential to become a useful clinical instrument for IOP measurement.     

Genetic association signal near NTN4 in Tourette syndrome

Tourette syndrome (TS) is a neurodevelopmental disorder with a complex genetic etiology. Through an international collaboration, we genotyped 42 single nucleotide polymorphisms (p < 10⁻³) from the recent TS genomewide association study (GWAS) in 609 independent cases and 610 ancestry‐matched controls. Only rs2060546 on chromosome 12q22 (p = 3.3 × 10⁻⁴) remained significant after Bonferroni correction. Meta‐analysis with the original GWAS yielded the strongest association to date (p = 5.8 × 10⁻⁷). Although its functional significance is unclear, rs2060546 lies closest to NTN4, an axon guidance molecule expressed in developing striatum. Risk score analysis significantly predicted case–control status (p = 0.042), suggesting that many of these variants are true TS risk alleles. Ann Neurol 2014;76:310–315     

Factors Predicting Long-Term Survival Following Pancreatic Resection for Ductal Adenocarcinoma of the Pancreas: 40 Years of Experience

Background

Long-term survival after resection for pancreas carcinoma has rarely been reported. Factors influencing long-term survival are still under debate. The aim of this study was to define predictors for long-term survival.

Methods

Between 1972 and 2004, a total of 415 patients underwent resection. Data were collected in a prospective data base. Data of 360 patients were available for further analysis in 2011. All specimens of long-term survivors were histologically reviewed.

Results

Long-term survivors (n?=?69) had a median survival of 91 months. Pathological re-evaluation of all specimens re-confirmed the diagnosis. Predictive factors for long-term survival in univariate analysis were no preoperative biliary stent, low CA 19-9 level, lack of blood transfusion, R0 resection, tumour diameter, and -grading, absence of lymph node or distant metastases, lymphangiosis, and perineural infiltration. Adjuvant chemotherapy showed a significant influence on overall survival but not on long-term survival. In multivariate analysis, lymph node ratio and volume of blood transfusion were predictors of long-term survival.

Conclusion

Nearly 20 % of patients with pancreas carcinoma who undergo surgical resection have a chance of long-term survival. Survival beyond 5 years is predicted by clinical and tumour-specific factors. Adjuvant chemotherapy might prolong overall survival but is, according to these results, unable to contribute to long-term survival. There is still a risk of recurrence after a 5- or even a 12-year mark. Survival beyond 5 or even 12 years, therefore, does not assure cure.     

Diagnostic Potential of a Luminex-Based Coronavirus Disease 2019 Suspension Immunoassay (COVID-19 SIA) for the Detection of Antibodies against SARS-CoV-2

Due to the current, rapidly increasing Coronavirus disease 2019 (COVID-19) pandemic, efficient and highly specific diagnostic methods are needed. The receptor-binding part of the spike (S) protein, S1, has been suggested to be highly virus-specific; it does not cross-react with antibodies against other coronaviruses. Three recombinant partial S proteins of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) expressed in mammalian or baculovirus-insect cells were evaluated as antigens in a Luminex-based suspension immunoassay (SIA). The best performing antigen (S1; amino acids 16-685) was selected and further evaluated by serum samples from 76 Swedish patients or convalescents with COVID-19 (previously PCR and/or serologically confirmed), 200 pre-COVID-19 individuals (180 blood donors and 20 infants), and 10 patients with acute Epstein-Barr virus infection. All 76 positive samples showed detectable antibodies to S1, while none of the 210 negative controls gave a false positive antibody reaction. We further compared the COVID-19 SIA with a commercially available enzyme immunoassay and a previously evaluated COVID-19 rapid antibody test. The results revealed an overall assay sensitivity of 100%, a specificity of 100% for both IgM and IgG, a quantitative ability at concentrations up to 25 BAU/mL, and a better performance as compared to the commercial assays, suggesting the COVID-19 SIA as a most valuable tool for efficient laboratory-based serology.     

Dogs as Sentinels for Flavivirus Exposure in Urban,Peri-Urban and Rural Hanoi,Vietnam

Diseases caused by flaviviruses, including dengue fever and Japanese encephalitis, are major health problems in Vietnam. This cross-sectional study explored the feasibility of domestic dogs as sentinels to better understand risks of mosquito-borne diseases in Hanoi city. A total of 475 dogs serum samples from 221 households in six districts of Hanoi were analyzed by a competitive enzyme-linked immunosorbent assay (cELISA) for antibodies to the pr-E protein of West Nile virus and other flaviviruses due to cross-reactivity. The overall flavivirus seroprevalence in the dog population was 70.7% (95% CI = 66.4–74.8%). At the animal level, significant associations between seropositive dogs and district location, age, breed and keeping practice were determined. At the household level, the major risk factors were rural and peri-urban locations, presence of pigs, coil burning and households without mosquito-borne disease experience (p < 0.05). Mosquito control by using larvicides or electric traps could lower seropositivity, but other measures did not contribute to significant risk mitigation of flavivirus exposure in dogs. These results will support better control of mosquito-borne diseases in Hanoi, and they indicate that dogs can be used as sentinels for flavivirus exposure.     

Enhancement by Interferon of the Expression of Surface Antigens on Murine Leukemia L 1210 Cells

Preparations of mouse interferon enhanced the expression of surface antigens of murine leukemia L 1210 cells, as determined by their alloantibody-absorbing capacity. The factor responsible for the enhancement of surface antigen expression could not be dissociated from the antiviral activity of interferon by standard physicochemical means. Likewise, interferon did not increase the antibody-absorbing capacity of an interferon-resistant subline of L 1210 cells. We conclude that interferon treatment of L 1210 cells is accompanied by modifications of the cell surface.