What (If Anything) is Wrong with High-Frequency Trading?

This essay examines three potential arguments against high-frequency trading and offers a qualified critique of the practice. In concrete terms, it examines a variant of high-frequency trading that is all about speed-low-latency trading-in light of moral issues surrounding arbitrage, information asymmetries, and systemic risk. The essay focuses on low-latency trading and the role of speed because it also aims to show that the commonly made assumption that speed in financial markets is morally neutral is wrong. For instance, speed is a necessary condition for low-latency trading's potential to cause harm in "flash crashes." On the other hand, it also plays a crucial role in a Lockean defense against low-latency trading being wasteful developed in this essay. Finally, this essay discusses the implications of these findings for related high-frequency trading techniques like futures arbitrage or latency arbitrage-as well as for an argument as to why quote stuffing is wrong. Overall, the qualifications offered in this essay act as a counterbalance to overblown claims about trading at high speeds being wrong.

Comparison of Uptake and Prices of Biosimilars in the US, Germany, and Switzerland.

Importance: Biologics account for a substantial proportion of health care expenditures. Their costs have been projected to reach US $452 billion in global spending by 2022. Given recent expiration of patent protection of biologics, a shift toward greater follow-on competition among biosimilars would be expected that would allow greater uptake and lower drug costs. Objective: To assess uptake and prices of biosimilars in the US compared with 2 European countries (Germany and Switzerland) with national mechanisms for drug price negotiation. Design, Setting, and Participants: In this cohort study, biologics and biosimilars that were approved in the US, Germany, and Switzerland until August 2020 were identified. Prices and sales data were extracted from public and commercial databases for the years 2011 to 2020. Data were analyzed from August 1, 2021, to February 28, 2022. Main Outcomes and Measures: Descriptive statistics were used to show temporal trends in the uptake of biosimilars and relative prices compared with those of reference products (ie, biologic agents) for each country. Descriptive analysis was also performed to compare the uptake of biosimilars between the 3 countries limited to biologics that have biosimilars on the market in all countries. To test if biosimilar awareness in each country increased over the last decade, a linear least squares regression was applied. Results: The study cohort included 15 biosimilars and 6 biologics for the US, 52 biosimilars and 15 biologics for Germany, and 28 biosimilars and 13 biologics for Switzerland. Uptake of biosimilars increased over time in all countries. On average, the biosimilar market share at launch was highest in Germany; however, it increased at the fastest rate in the US. Monthly treatment costs of biosimilars in the US were a median of 1.94 (IQR, 1.78-2.44) and 2.74 (IQR, 1.91-3.46) higher than corresponding costs in Germany and Switzerland, respectively. Conclusions and Relevance: The findings of this cohort study suggest that more biosimilars have been marketed in Germany and Switzerland than in the US. Policies that counter anticompetitive practices in the US could allow biosimilars to enter the market sooner and could also lower health care costs with improved access. Awareness of biosimilars should be promoted to increase uptake of biosimilars globally.

Price changes and within-class competition of cancer drugs in the USA and Europe: a comparative analysis.

BACKGROUND: Cancer drugs are a major component of pharmaceutical spending in the USA and Europe. The number of approved cancer drugs continues to increase. More new drugs with overlapping mechanisms of action and similar approved indications might be expected to decrease prices within drug classes. We compared patterns of price changes for cancer drugs within the same class in the USA and in two European countries (Germany and Switzerland) with national mechanisms for drug price negotiation. METHODS: For this comparative analysis, we identified cancer drugs approved for the treatment of solid cancers in the USA and Europe (Germany and Switzerland) between Jan 1, 2009, and Dec 31, 2020, using the US Food and Drug Administration's Drugs@FDA database and the European Medicines Agency's publicly available database. We considered cancer drugs as within-class competitors if they were approved for the same indication and had the same biological mechanism. We calculated monthly treatment prices for each drug, median price changes at launch and over time, and differences within and across drug classes. European price data were converted to US dollars by applying the exchange rates on Dec 1, 2020, and prices were adjusted for inflation. Median changes in the drugs' monthly treatment prices at 2 and 4 years after market entry across and within drug classes were also assessed. For the USA, correlations in relative price changes between all pairs of drugs within and across drug classes were calculated with Spearman's rank correlation. FINDINGS: Our study cohort comprised 12 drug classes covering nine indications. With the exception of one drug, increasing prices were observed within and across all drug classes in the USA (median 6·07% [range -3·60 to 33·83] 2 years after market entry, and 15·31% [-4·15 to 54·64] 4 years after market entry). By contrast, in Europe, prices generally decreased over time or did not increase more than inflation (2 years after market entry: -21·01% [range -50·72 to 12·71] in Germany and -1·48% [-26·81 to 1·69] in Switzerland; 4 years after market entry: -25·54% [-51·81 to 11·63] in Germany and -13·02% [-43·83 to 18·31] in Switzerland). In the USA, most prices changes within and across drug classes occurred at the end and beginning of the year (ie, from Dec 1 to Jan 31). In the USA, correlation for price changes was r=0·29 (SD 0·36) for within-class drugs and r=0·28 (0·36) for drugs across drug classes. INTERPRETATION: Competition within classes of cancer drugs generally did not constrain rising prices in the USA. Price negotiations, as practised in Germany or Switzerland, could help address the high prices of cancer drugs in the USA. FUNDING: Swiss Cancer Research Foundation (Krebsforschung Schweiz), Swiss National Science Foundation, and Arnold Ventures.

Occurrence and aetiology of subclinical mastitis in water buffalo in Bangladesh.

Subclinical mastitis (SCM) in water buffalo is a production disease associated with decreased milk yield and impaired milk quality and safety. Water buffalo is an important livestock species in Bangladesh, but information about the occurrence and aetiology of SCM in this species is scarce. A cross-sectional study was conducted as part of the Udder Health Bangladesh Programme to (i) determine the occurrence of SCM and bulk milk somatic cell count (SCC) in water buffalo in Bangladesh, (ii) identify pathogens causing SCM and (iii) evaluate penicillin resistance in isolated staphylococci strains. Sixteen buffalo farms in the Bagerhat and Noakhali regions of Bangladesh were selected for study and a bulk milk sample was collected from each farm. In addition, 299 udder quarter milk samples were collected from 76 animals. The bulk milk samples were assessed by direct SCC and the quarter milk samples by California mastitis test (CMT). The occurrence of SCM calculated at quarter and animal level was 42.5 and 81.6%, respectively. Milk samples from 108 CMT-positive quarters in 48 animals and 38 randomly selected CMT-negative quarters in 24 animals were investigated using bacteriological culture. Estimated mean bulk milk SCC was 195 000 cells/ml milk (range 47 000- 587 000 cells/ml milk). On culture, estimated quarter-level intramammary infection (IMI) was 40.4%. The identity of isolated bacteria was confirmed by MALDI-TOF mass spectrometry. Non-aureus staphylococci (NAS) were the most common pathogens (24.7%) and, among 36 NAS tested, 36.1% were resistant to penicillin. Thus there was high occurrence of SCM on the study farms, with relatively high penicillin resistance in NAS. Further studies are needed to identify underlying risk factors and develop an udder health control strategy for water buffalo in Bangladesh.

Patients' access to drugs with rebates in Switzerland - Empirical analysis and policy implications for drug pricing in Europe.

BACKGROUND: Many European countries introduced (confidential) rebates in the past years. Authorities and manufacturers argue that this strategy allows reduction of spending on high-cost drugs, and quick access of innovative drugs. We evaluated these arguments using Switzerland as an example, one of the last countries with transparent rebates. METHODS: We identified all drugs granted rebates in Switzerland and all new drugs without rebates between January 2012 and October 2020. We assessed the amount of introduced drugs with and without rebates over time, clinical benefit of drugs with rebates, and duration between approval and price determination. FINDINGS: Our study cohort included 51 drugs with rebates, the majority were cancer drugs (32; 63%). 15/51 (29%) had high clinical benefit, 25/51 (49%) low benefit and for 11/51 (22%) benefit could not be assessed. The number of drugs with rebates increased in recent years. Time duration between approval and price determination was 302 days in median for drugs with and 106 days for drugs without rebates. INTERPRETATION: Drugs with rebates may hamper access to drugs and lead to overpayment. Improving transparency on actual drug prices and stronger cooperation between countries could help national authorities to make better informed pricing decisions, and improve access of innovative drugs to patients. FUNDING: This study was partially funded by the Swiss Cancer Research Foundation (Krebsforschung Schweiz) and the Swiss National Foundation (SNF).

Dapagliflozin in patients with type II diabetes mellitus, with and without elevated triglyceride and reduced high-density lipoprotein cholesterol levels.

BACKGROUND: Dapagliflozin is a selective sodium-glucose cotransporter 2 inhibitor that improves glycemic control in patients with type II diabetes mellitus (T2DM) by reducing renal glucose reabsorption. OBJECTIVE: The aim was to evaluate the lipid effects of dapagliflozin 10 mg or placebo in patients with T2DM with/without baseline elevated triglyceride and reduced high-density lipoprotein (HDL) cholesterol levels. METHODS: This was a post hoc analysis of 10 phase 3, placebo-controlled studies of dapagliflozin 10 mg (N = 2237) or placebo (N = 2164) administered for 24 weeks in patients with T2DM. Patients with elevated triglyceride (≥150 mg/dL [1.69 mmol/L]) and reduced HDL cholesterol levels (<40 mg/dL [1.04 mmol/L] in men; <50 mg/dL [1.29 mmol/L] in women) were included (group A). The reference group (group B) included patients who did not meet the defined lipid criteria. RESULTS: The effects of dapagliflozin on fasting lipid profiles were generally similar in the 2 lipid groups (ie, groups A and B) and, compared with placebo, were associated with minor increases in non-HDL cholesterol, low-density lipoprotein, and HDL cholesterol levels. The effects on triglyceride levels were inconsistent. The incidence of adverse events (AEs)/serious AEs, and AEs of genital infection, urinary tract infection, volume reduction, renal function, and hypoglycemia were similar in the 2 lipid groups. CONCLUSION: Patients with T2DM treated with dapagliflozin experienced minor changes in lipid levels; the changes were generally similar in the 2 lipid groups. The clinical significance of these changes in lipids is unclear, especially in view of the positive effects of dapagliflozin on other cardiovascular disease risk factors.

The effects of block training on pacing during 20-km cycling time trial.

The aim of this study was to determine the effects of block training (BL) on pacing during a 20-km hilly cycling time trial (TT) in trained cyclists. Twenty male cyclists were separated into 2 groups: control and BL. The training of each cyclist was monitored during a period of 3 weeks. In the first week cyclists performed an overload period of 7 consecutive days of high-intensity interval training followed by 2 weeks of normal training. Cyclists performed 1 TT before intervention and 2 TT after 7 and 14 days at the end of training. Each training session consisted of 10 sets of 3 repeated maximal-effort sprints (15, 30, and 45 s) with an effort/recovery duration ratio of 1:5. The main finding of this study was that the power output displayed a significantly higher start from the start until the halfway point of the TT (p < 0.05). Additionally, power output was characterized by a significant higher end spurt in the final 2 km in the BL after 2 weeks at the end of training (p < 0.05). In addition, after 2 weeks at the end of the overload period the distribution of cadence was significantly lower throughout the TT (p < 0.01). Therefore, a short period of consecutive days of intense training enhances cycling performance and changes the power output in the beginning and final part of the TT in trained cyclists.

Genome-wide analysis of DNA methylation in subjects with type 1 diabetes identifies epigenetic modifications associated with proliferative diabetic retinopathy.

BACKGROUND: Epigenetic variation has been linked to several human diseases. Proliferative diabetic retinopathy (PDR) is a major cause of vision loss in subjects with diabetes. However, studies examining the association between PDR and the genome-wide DNA methylation pattern are lacking. Our aim was to identify epigenetic modifications that associate with and predict PDR in subjects with type 1 diabetes (T1D). METHODS: DNA methylation was analyzed genome-wide in 485,577 sites in blood from cases with PDR (n = 28), controls (n = 30), and in a prospective cohort (n = 7). False discovery rate analysis was used to correct the data for multiple testing. Study participants with T1D diagnosed before 30 years of age and insulin treatment within 1 year from diagnosis were selected based on 1) subjects classified as having PDR (cases) and 2) subjects with T1D who had had diabetes for at least 10 years when blood DNA was sampled and classified as having no/mild diabetic retinopathy also after an 8.7-year follow-up (controls). DNA methylation was also analyzed in a prospective cohort including seven subjects with T1D who had no/mild diabetic retinopathy when blood samples were taken, but who developed PDR within 6.3 years (converters). The retinopathy level was classified by fundus photography. RESULTS: We identified differential DNA methylation of 349 CpG sites representing 233 unique genes including TNF, CHI3L1 (also known as YKL-40), CHN2, GIPR, GLRA1, GPX1, AHRR, and BCOR in cases with PDR compared with controls. The majority of these sites (79 %) showed decreased DNA methylation in cases with PDR. The Natural Killer cell-mediated cytotoxicity pathway was found to be significantly (P = 0.006) enriched among differentially methylated genes in cases with PDR. We also identified differential DNA methylation of 28 CpG sites representing 17 genes (e.g. AHRR, GIPR, GLRA1, and BCOR) with P <0.05 in the prospective cohort, which is more than expected by chance (P = 0.0096). CONCLUSIONS: Subjects with T1D and PDR exhibit altered DNA methylation patterns in blood. Some of these epigenetic changes may predict the development of PDR, suggesting that DNA methylation may be used as a prospective marker of PDR.

Steroid responsive encephalopathy associated with autoimmune thyroiditis following ipilimumab therapy: a case report.

BACKGROUND: Ipilimumab is a cytotoxic T-lymphocyte-associated protein 4 receptor antibody used for immunotherapy in cancer. Several immune-related adverse events are known. Steroid responsive encephalopathy associated with autoimmune thyroiditis is an autoimmune encephalopathy associated with Hashimoto's Disease and elevated serum levels of the related antibodies (anti-thyroid-peroxidase antibody or anti-thyroglobulin antibody). Our case implies that steroid responsive encephalopathy associated with autoimmune thyroiditis may be another previously unreported side effect of ipilimumab therapy. CASE PRESENTATION: We report the case of a 64 years old caucasian patient with prostatic cancer who received ipilimumab therapy in a clinical trial. He presented with aphasia, tremor and ataxia, myocloni, hallucinations, anxiety and agitation in turns with somnolence. Cranial nerves, deep tendon reflexes, motor and sensory functions were normal. Electroencephalography showed background slowing but no epileptic discharges. Brain magnetic resonance imaging was normal and showed no signs of hypophysitis. Cerebrospinal fluid findings ruled out infection and neoplastic meningitis. Anti-thyroid antibodies (anti-thyroid-peroxidase antibody and anti-thyroglobulin antibody) were heavily increased. Assuming steroid responsive encephalopathy associated with autoimmune thyroiditis the patient was treated with 1,000 mg methylprednisolone i.v. for 3 days and continued with 1 mg/kg orally. On the 3rd day of treatment the patient's condition started to improve. Within the next few days he gradually returned to his previous state, and electroencephalography eventually showed only slight slowing. Seven months later the patient's condition was stable, and anti-thyroid antibodies were no more detectable. CONCLUSION: Steroid responsive encephalopathy associated with autoimmune thyroiditis may be a hitherto unrecognized complication of ipililumab treatment and should be taken into consideration in patients developing central nervous symptoms undergoing this treatment.

Photocoagulation of human retinal pigment epithelium in vitro: unravelling the effects on ARPE-19 by transcriptomics and proteomics.

PURPOSE: Despite the extensive use of retinal photocoagulation for ischaemia and vascular leakage in retinal vascular disease, the molecular mechanisms behind its clinical beneficial effects are still poorly understood. One important target of laser irradiation is the retinal pigment epithelium (RPE). In this study, we aimed at identifying the isolated effects of photocoagulation of RPE at both the mRNA and protein expression levels. METHODS: Human ARPE-19 cells were exposed to photocoagulation. Gene expression and protein expression were compared to untreated cells using microarray and liquid chromatography-mass spectrometry analysis. Genes and proteins queried by microarray and mass spectrometry were subjected to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database pathway analyses. RESULTS: Laser irradiation resulted in an induction of the cytoprotective heat-shock protein subfamily Hsp70 as well as in a suppression of the vascular permeability factor carbonic anhydrase 9 (CA9). These expression patterns were evident at both the mRNA and protein levels. KEGG pathway analyses revealed genes and proteins involved in cellular turnover, repair and inflammation. CONCLUSIONS: By characterizing the transcriptional and translational effects of laser coagulation on the RPE cells in culture, we have revealed responses, which might contribute to some of the beneficial effects obtained by photocoagulation for ischaemia and vascular leakage in retinal vascular disease.

Incorporating parasite data in population structure studies of South African sardine Sardinops sagax.

A multidisciplinary approach has been applied to examine the population structure of sardine Sardinops sagax off South Africa, where this species supports significant fisheries and is also of ecological and eco-tourism importance. Observations of discontinuous sardine distribution patterns, discrete spawning grounds and significant spatial differences in a variety of phenotypic characteristics have suggested the existence of discrete western, southern and eastern sardine sub-populations or stocks. The use of parasites as biological tags to elucidate sardine population structure has recently been investigated, and strong spatial gradients around South Africa in the prevalence, mean infection intensity and mean abundance of a digenean 'tetracotyle' type metacercarial endoparasite considered to be of the genus Cardiocephaloides and found in the humours of fish eyes support and have proved particularly convincing evidence for the sardine multiple stock hypothesis. A discontinuous distribution in the occurrence of another parasite, the coccidean Eimeria sardinae found in fish testes, has provided additional but weaker evidence of discrete stocks. These results have contributed to a changed understanding of the population structure of South African sardine and have significant implications for management of the fisheries for this species.

GAD autoantibody affinity in adult patients with latent autoimmune diabetes, the study participants of a GAD65 vaccination trial.

OBJECTIVE: Patients with latent autoimmune diabetes in adults (LADA) express autoantibodies against the 65-kDa isoform of GAD (GADA). Intervention with recombinant human GAD65 formulated with aluminium hydroxide (GAD-alum) given twice subcutaneously to LADA patients at intervals of 4 weeks was safe and did not compromise ß-cell function in a Phase II clinical trial. GADA affinity has been shown to predict progression to type 1 diabetes. Here, we asked whether GADA affinity was affected by the GAD65 antigen-specific vaccination and/or associated with ß-cell function in participants of this trial. RESEARCH DESIGN AND METHODS: GADA affinity was measured in sera of 46 LADA patients obtained prior to the first week and 20 weeks after the second injection with GAD-alum or placebo using competitive binding experiments with [125I]-labeled and unlabeled human GAD65. RESULTS: At baseline, GADA affinities ranged from 1.9 × 10(7) to 5.0 × 10(12) L/mol (median 2.8 × 10(10) L/mol) and were correlated with GADA titers (r = 0.47; P = 0.0009), fasting (r = -0.37; P = 0.01) and stimulated (r = -0.40; P = 0.006) C-peptide concentrations, and HbA1c (r = 0.39; P = 0.007). No significant changes in affinity were observed from baseline to week 24. Patients with GADA affinities in the lower first quartile (<4 × 10(9) L/mol) had better preserved fasting C-peptide concentrations at baseline than those with higher affinities (mean 1.02 vs. 0.66 nmol/L; P = 0.004) and retained higher concentrations over 30 months of follow-up (mean 1.26 vs. 0.62 nmol/L; P = 0.01). CONCLUSIONS: Intervention with GAD-alum in LADA patients had no effect on GADA affinity. Our data suggest that patients with low GADA affinity have a prolonged preservation of residual ß-cell function.

Cardiovascular disease in relation to diabetes status in immigrants from the Middle East compared to native Swedes: a cross-sectional study.

BACKGROUND: Type 2 diabetes is highly prevalent in immigrants to Sweden from Iraq, but the prevalence of cardiovascular disease (CVD) and its risk factors are not known. In this survey we aimed to compare the prevalence of CVD and CVD-associated risk factors between a population born in Iraq and individuals born in Sweden. METHODS: This population-based, cross-sectional study comprised 1,365 Iraqi immigrants and 739 Swedes (age 30-75 years) residing in the same socioeconomic area in Malmö, Sweden. Blood tests were performed and socio-demography and lifestyles were characterized. To investigate potential differences in CVD, odds ratios (ORs) with 95% confidence intervals (CIs) were estimated by multivariate logistic regression analysis with adjustment for metabolic, lifestyle and psychosocial risk factors for CVD. Outcome measures were odds of CVD. RESULTS: There were no differences in self-reported prevalence of CVD between Iraqi- and Swedish-born individuals (4.0 vs. 5.5%, OR 0.9, 95% CI 0.4-1.8). However, the prevalence of type 2 diabetes was higher in Iraqi compared to Swedish participants (8.4 vs. 3.3%, OR = 4.2, 95% CI 2.6-6.7). Moreover, among individuals with type 2 diabetes, Iraqis had a higher prevalence of CVD (22.8 vs. 8.0%, OR = 4.2, 95% CI 0.9-20.0), after adjustment for age and sex. By contrast, among those without diabetes, immigrants from Iraq had a lower prevalence of CVD than Swedes (2.2 vs. 5.5%, OR = 0.6, 95% CI 0.3-0.9).Type 2 diabetes was an independent risk factor for CVD in Iraqis only (OR = 6.8, 95% CI 2.8-16.2). This was confirmed by an interaction between country of birth and diabetes (p = 0.010). In addition, in Iraqis, type 2 diabetes contributed to CVD risk to a higher extent than history of hypertension (standardized OR 1.5 vs. 1.4). CONCLUSIONS: This survey indicates that the odds of CVD in immigrants from Iraq are highly dependent on the presence or absence of type 2 diabetes and that type 2 diabetes contributes with higher odds of CVD in Iraqi immigrants compared to native Swedes. Our study suggests that CVD prevention in immigrants from the Middle East would benefit from prevention of type 2 diabetes.

Photocoagulation of human retinal pigment epithelial cells in vitro: evaluation of necrosis, apoptosis, cell migration, cell proliferation and expression of tissue repairing and cytoprotective genes.

AIMS: Sight-threatening diabetic retinopathy has been treated with photocoagulation for decades but the mechanisms behind the beneficial clinical effects are poorly understood. One target of irradiation and a potential player in this process is the retinal pigment epithelium (RPE). Here we establish an in vitro model for photocoagulation of human RPE cells. METHODS: ARPE-19 cells were exposed to photocoagulation and studied at various time points up to 168h. Lesion morphology, necrosis and apoptosis were investigated by light microscopy; LIVE/DEAD staining and measurements of lactate dehydrogenase activity; and TUNEL- and ELISA-based quantification of DNA fragments, respectively. Cell migration and proliferation were explored using docetaxel and mitomycin C; temporal and spatial changes in proliferation were assessed by confocal immunofluorescence of proliferating cell nuclear antigen. Gene expression was measured by qPCR. RESULTS: Photocoagulation of ARPE-19 resulted in denaturation of proteins and reproducible lesion formation. A transient peak in necrosis, followed by a peak in apoptosis was observed in cells within the lesions at 6h and 24h, respectively after photocoagulation. Cell proliferation was depressed during the first hours after photocoagulation, back to control levels at 24h and augmented in the following days. These effects were not limited to cells in the lesions, but also evident in neighbouring cells. Changes in cell proliferation during lesion repair were preceded by changes in cell migration. Altered mRNA expression of genes previously implicated in the regulation of cell proliferation (FOS, IL-1ß, IL-8, HMGA2), migration and tissue repairing (TGFBR2, ADAMTS6, TIMP3, CTGF) was observed, as well as increased expression of the alarmin IL33 and the cytoprotective gene HSPA6. CONCLUSIONS: Using a laser system and experimental settings that comply with standards used in clinical practice, we have established a suitable model for in vitro photocoagulation of human RPE cells to isolate their contribution to the beneficial effects of laser treatment.

Profile of intraocular tumour necrosis factor-α and interleukin-6 in diabetic subjects with different degrees of diabetic retinopathy.

PURPOSE: To assess and correlate the levels of inflammatory mediators in the eyes from non-diabetic and diabetic subjects without retinopathy (NDR), with non-proliferative diabetic retinopathy (NPDR) or with proliferative diabetic retinopathy (PDR) to corresponding erum levels. METHODS: The levels of interleukin 1ß, interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were analysed by an ELISA-mimicking technique in the vitreous from 26 diabetic subjects with active PDR and 27 non-diabetic subjects, or by a multiplex bead assay in the aqueous humour from 35 diabetic subjects with NDR/NPDR and 40 non-diabetic subjects. Intraocular protein production was estimated in vitreous specimens by calculating a vitreous/serum ratio. RESULTS: In the vitreous, IL-6 was higher in diabetic [157.5 (25.0-1401.0) pg/ml; median (min-max)] than in non-diabetic subjects [44.0 (5.0-4425) pg/ml; p = 0.021]. The vitreous/serum ratio was high (55.5:1 and 16:1, respectively), suggesting intraocular production. TNF-α was lower in diabetic [18.0 (8.0-46.0) pg/ml] than in non-diabetic subjects [22.0 (13.0-47.0) pg/ml; p = 0.034], but the vitreous/serum ratio was elevated in both groups (2:1 and 3.4:1, respectively). TNF-α levels were higher in serum from diabetic subjects [9.0 (5.0-53.0) pg/ml versus 6.7 (3.0-11.0) pg/ml; p < 0.001]. Aqueous levels of inflammatory mediators did not differ between diabetic subjects with NDR/NPDR and non-diabetic subjects despite elevated TNF-α in serum [27.8 (6.8-153.7) pg/ml versus 16.4 (4.1-42.4) pg/ml; p = 0.021]. CONCLUSION: Intraocular inflammation seems to be involved in PDR but does not seem to be prominent in early retinopathy stages, i.e. NDR or NPDR. Diabetic subjects have an overall increased inflammatory activity compared to non-diabetic subjects, as demonstrated by increased serum levels of TNF-α.

Inactivation of vaccinia virus by natural sunlight and by artificial UVB radiation.

This study determined the sensitivity of vaccinia virus, an orthopox virus commonly used as a surrogate for variola virus (etiological agent of smallpox), exposed to UVB radiation emitted by a solar simulator, or to direct natural sunlight. The data obtained indicate that: (1) the virucidal effect of natural sunlight can be mimicked adequately by an artificial light source with similar spectral characteristics in the UVB, (2) viral sensitivity to UVB or to solar radiation can be correlated with experimental data previously obtained with UVC, (3) the correlation factor between virus inactivation by solar radiation (measured at 300 ± 5 nm) and by UVC (254 nm) is between 33 and 60, and (4) the sensitivity of viruses either dry on glass surfaces or in liquid suspension is similar when in the presence of similar amounts of cellular debris and growth media. The findings reported in this study should assist in estimating the threat posed by the persistence of virus during epidemics or after an accidental or intentional release.

Role of pattern, regularity, and silent intervals in auditory stream segregation based on inter-aural time differences.

Tone triplets separated by a pause (ABA_) are a popular tone-repetition pattern to study auditory stream segregation. Such triplets produce a galloping rhythm when integrated, but isochronous rhythms when segregated. Other patterns lacking a pause may produce less-prominent rhythmic differences but stronger streaming. Here, we evaluated whether this difference is readily explained by the presence of the pause and potentially associated with the reduction of adaptation, or whether there is contribution of tone pattern per se. Sequences with repetitive ABA_ and ABAA patterns were presented in magnetoencephalography. A and B tones were separated by differences in inter-aural time differences (ΔITD). Results showed that the stronger streaming of ABAA was associated with a more prominent release from the adaptation of the P(1)m in auditory cortex. We further compared behavioral streaming responses for patterns with and without pauses, and varied the position of the pause and pattern regularity. Results showed a major effect of the pauses' presence, but no prominent effects of tone pattern or pattern regularity. These results make a case for the existence of an early, primitive streaming mechanism that does not require an analysis of the tone pattern at later stages suggested by predictive-coding models of auditory streaming. The results are better explained by the simpler population-separation model and stress the previously observed role of neural adaptation for streaming perception.