Fire over the past decade has affected forests in the San Bernardino Mountains of southern California, providing an excellent opportunity to examine how this disturbance, and subsequent post-fire salvage logging, influenced California spotted owl (Strix occidentalis occidentalis) breeding-season site occupancy dynamics there and in the nearby San Jacinto Mountains. Using occupancy survey data from 2003 to 2011 for all-detections and pairs-only data, we estimated annual extinction and colonization probabilities at 71 burned and 97 unburned breeding-season sites before and after fire, while controlling for confounding effects of non-fire-related temporal variation and among-site differences in habitat characteristics. We found no statistically significant effects of fire or salvage logging on occupancy dynamics of spotted owls of southern California. However, we found some evidence that fire and logging effects could be biologically meaningful. For pairs data, the model-averaged mean of fire-related effects on colonization and extinction probabilities resulted in a 0.062 lesser site-occupancy probability in burned sites 1-year post-fire relative to unburned sites. Post-fire salvage logging reduced occupancy an additional 0.046 relative to sites that only burned. We documented a threshold-type relationship between extinction and colonization probabilities and the amount of forested habitat (conifer or hardwood tree cover types) that burned at high severity within a 203-ha core area around spotted owl nests and roost centroids. Sites where approximately 0-50 ha of forested habitat within the core area burned at high severity had extinction probabilities similar to unburned sites, but where more than approximately 50 ha of forested habitat burned severely, extinction probability increased approximately 0.003 for every additional hectare severely burned. The majority (75%) of sites burned below this threshold. Sites where high-severity fire affected >50 ha of forested habitat could still support spotted owls, so all burned sites should be monitored for occupancy before management actions such as salvage logging are undertaken that could be detrimental to the subspecies. We also recommend that managers strive to reduce human-caused ignitions along the wildland-urban interface, particularly at lower elevations where owl sites are at higher risk of extinction from fire. Ó 2013 The Wildlife Society.

Background Recent studies have suggested a blunted immune response to messenger RNA vaccines in solid organ transplant (SOT) recipients. Given the paucity of data on adenovirus vector vaccines use in immunosuppressed SOT recipients, we sought to describe the safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine in a heart transplant population. Methods Heart transplant recipients aged 18 – 70 years scheduled to receive 2 doses of the ChAdOx1 nCoV-19 vaccine were enrolled into a prospective study involving serum analysis to define their antibody response. An antibody concentration against the spike protein receptor-binding domain of ≥0.8 U/ml was deemed a detectable antibody response. Results A total of 99 heart transplant recipients (mean age 51±12.5 years, 28% female) were enrolled. No major adverse events were recorded after vaccination; minor symptoms included injection site pain (24%), fatigue (21%) and headache (14%). Of 7 patients with prior SARS-CoV-2 confirmed by PCR testing, all (100%) had detectable antibody responses following 1 st and 2 nd vaccine doses. In those with no prior SARS-CoV-2 infection (n=92), 24% (n=22) showed an antibody response after dose 1, increasing to 34.8% (n=32) after dose 2, p<0.001. Chronic kidney disease (CKD) stage ≥3 (OR 4.7, 95%CI 1.5-15, p=0.009) and mycophenolate use (OR 4.1, 95%CI 1.2-14, p=0.02) were independently associated with a non-detectable antibody response. Conclusions Almost two-thirds of heart transplant recipients aged 18-70 years without a history of prior SARS-CoV-2 infection failed to develop a detectable antibody response following administration of the ChAdOx1 nCoV-19 vaccine. Patient phenotyping may help predict which patients are less likely to develop detectable antibody responses.

This paper reports the successful fabrication of an impedance-based miniaturized biosensor and its application for ultrasensitive Prostate-Specific Antigen (PSA) detection in standard and real human plasma solution, spiked with different PSA concentrations. The sensor was fabricated using photolithographic techniques, while monoclonal antibodies specific to human PSA were used as primary capture antibodies. Electrochemical impedance spectroscopy (EIS) was employed as a detection technique. The sensor exhibited a detection limit of 1 pg/ml for PSA with minimal nonspecific binding (NSB). This detection limit is an order of magnitude lower than commercial PSA ELISA assays available on the market. The sensor can be easily modified into an array for the detection of other biomolecules of interest, enabling accurate, ultrasensitive, and inexpensive point-of-care sensing technologies.

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In this study, the upregulated expression level of vascular endothelial growth factor (VEGF) in a pulmonary endothelial cell line (HPMEC-ST1.6R) infected with dengue virus serotypes 1, 2, 3, and 4 (DENV-1, -2, -3 and -4), was investigated. This cell line exhibits the major constitutive and inducible endothelial cell characteristics, as well as angiogenic response. Infection by all four DENV serotypes was confirmed by an observed cytopathic effect (CPE), as well as RT-PCR (reversetranscription polymerase chain reaction) assays. As we had previously reported, the DENVinfected HPMEC-ST1.6R cells exhibited an elongated cytoplasmic morphology, possibly representing a response to VEGF and activation of angiogenesis. In this study, increase in VEGF expression level at designated time points of 0, 8, 24, 96 and 192 hours post-infection was investigated, using a microbead-based Bio-Plex immunoassay. Increased level of VEGF expression in infected-HPMEC-ST1.6R was detected at 8 hours post-infection. Interestingly, VEGF expression level began to decrease up to 96 hours post-infection, after which an upsurge of increased VEGF expression was detected at 192 hours post-infection. This profile of VEGF upregulated expression pattern associated with DENV infection appeared to be consistent among all four DENV-serotypes, and was not observed in mock-infected cells. In this study, the expression level of VEGF, a wellestablished vascular permeabilizing agent was shown to be elevated in a time-dependent manner, and exhibited a unique dual-response profile, in a DENV-infected endothelial cell. The experimental observation described here provided additional insights into potential mechanism for VEGFmediated vascular leakage associated with DENV, and support the idea that there are potential applications of anti-VEGF therapeutic interventions for prevention of severe DENV infections.