Clinician Attitudes Toward Suicide Prevention Practices and Their Implementation: Findings From the System of Safety Study

OBJECTIVE

The authors aimed to assess clinicians' attitudes toward suicide-related practices and their implementation, across roles and settings, before implementation of the Zero Suicide model in a health care system.

METHODS

Clinicians (N=5,559) were invited to complete a survey assessing demographic characteristics; confidence and self-reported suicide-related practice; leadership buy-in; and attitudes toward suicide prevention, safety planning, and continuous quality improvement (CQI).

RESULTS

Of 1,224 respondents, most felt confident conducting suicide screening but less confident performing other suicide-related care. Provider role and care setting were significantly associated with confidence (p<0.001, Kruskal-Wallis H test) and practice (p<0.001, Kruskal-Wallis H test) of providing suicide prevention care, with behavioral health providers and providers in the emergency department (ED) reporting the highest confidence. Attitudes toward safety planning were more positive among women (p<0.001, t test) and behavioral health providers (p<0.001, F test) than among their counterparts or peers. Positive attitudes toward CQI were significantly associated with male sex (p=0.01), non-White race (p=0.03), younger age (p=0.02), fewer years working in health care (p<0.001), administrative role (p<0.001), working in the ED (p<0.001), outpatient settings (p<0.02), and medical provider role (p<0.001).

CONCLUSIONS

Behavioral health providers and those in the ED reported feeling prepared to deliver suicide-related care, with nurses feeling less confident and less supported. Initiatives to improve suicide-related care should account for clinical role and care setting during planning. CQI could help engage a broader range of clinicians in suicide-related care improvements.

Performance of Rapid Antigen Tests to Detect Symptomatic and Asymptomatic SARS-CoV-2 Infection : A Prospective Cohort Study

BACKGROUND

The performance of rapid antigen tests (Ag-RDTs) for screening asymptomatic and symptomatic persons for SARS-CoV-2 is not well established.

OBJECTIVE

To evaluate the performance of Ag-RDTs for detection of SARS-CoV-2 among symptomatic and asymptomatic participants.

DESIGN

This prospective cohort study enrolled participants between October 2021 and January 2022. Participants completed Ag-RDTs and reverse transcriptase polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 every 48 hours for 15 days.

SETTING

Participants were enrolled digitally throughout the mainland United States. They self-collected anterior nasal swabs for Ag-RDTs and RT-PCR testing. Nasal swabs for RT-PCR were shipped to a central laboratory, whereas Ag-RDTs were done at home.

PARTICIPANTS

Of 7361 participants in the study, 5353 who were asymptomatic and negative for SARS-CoV-2 on study day 1 were eligible. In total, 154 participants had at least 1 positive RT-PCR result.

MEASUREMENTS

The sensitivity of Ag-RDTs was measured on the basis of testing once (same-day), twice (after 48 hours), and thrice (after a total of 96 hours). The analysis was repeated for different days past index PCR positivity (DPIPPs) to approximate real-world scenarios where testing initiation may not always coincide with DPIPP 0. Results were stratified by symptom status.

RESULTS

Among 154 participants who tested positive for SARS-CoV-2, 97 were asymptomatic and 57 had symptoms at infection onset. Serial testing with Ag-RDTs twice 48 hours apart resulted in an aggregated sensitivity of 93.4% (95% CI, 90.4% to 95.9%) among symptomatic participants on DPIPPs 0 to 6. When singleton positive results were excluded, the aggregated sensitivity on DPIPPs 0 to 6 for 2-time serial testing among asymptomatic participants was lower at 62.7% (CI, 57.0% to 70.5%), but it improved to 79.0% (CI, 70.1% to 87.4%) with testing 3 times at 48-hour intervals.

LIMITATION

Participants tested every 48 hours; therefore, these data cannot support conclusions about serial testing intervals shorter than 48 hours.

CONCLUSION

The performance of Ag-RDTs was optimized when asymptomatic participants tested 3 times at 48-hour intervals and when symptomatic participants tested 2 times separated by 48 hours.

PRIMARY FUNDING SOURCE

National Institutes of Health RADx Tech program.

Design and implementation of a digital site-less clinical study of serial rapid antigen testing to identify asymptomatic SARS-CoV-2 infection

Background

Rapid antigen detection tests (Ag-RDT) for SARS-CoV-2 with emergency use authorization generally include a condition of authorization to evaluate the test's performance in asymptomatic individuals when used serially. We aim to describe a novel study design that was used to generate regulatory-quality data to evaluate the serial use of Ag-RDT in detecting SARS-CoV-2 virus among asymptomatic individuals.

Methods

This prospective cohort study used a siteless, digital approach to assess longitudinal performance of Ag-RDT. Individuals over 2 years old from across the USA with no reported COVID-19 symptoms in the 14 days prior to study enrollment were eligible to enroll in this study. Participants throughout the mainland USA were enrolled through a digital platform between October 18, 2021 and February 15, 2022. Participants were asked to test using Ag-RDT and molecular comparators every 48 hours for 15 days. Enrollment demographics, geographic distribution, and SARS-CoV-2 infection rates are reported.

Key Results

A total of 7361 participants enrolled in the study, and 492 participants tested positive for SARS-CoV-2, including 154 who were asymptomatic and tested negative to start the study. This exceeded the initial enrollment goals of 60 positive participants. We enrolled participants from 44 US states, and geographic distribution of participants shifted in accordance with the changing COVID-19 prevalence nationwide.

Conclusions

The digital site-less approach employed in the "Test Us At Home" study enabled rapid, efficient, and rigorous evaluation of rapid diagnostics for COVID-19 and can be adapted across research disciplines to optimize study enrollment and accessibility.

Performance of Rapid Antigen Tests to Detect Symptomatic and Asymptomatic SARS-CoV-2 Infection

Background

Performance of rapid antigen tests for SARS-CoV-2 (Ag-RDT) varies over the course of an infection, and their performance in screening for SARS-CoV-2 is not well established. We aimed to evaluate performance of Ag-RDT for detection of SARS-CoV-2 for symptomatic and asymptomatic participants.

Methods

Participants >2 years old across the United States enrolled in the study between October 2021 and February 2022. Participants completed Ag-RDT and molecular testing (RT-PCR) for SARS-CoV-2 every 48 hours for 15 days. This analysis was limited to participants who were asymptomatic and tested negative on their first day of study participation. Onset of infection was defined as the day of first positive RT-PCR result. Sensitivity of Ag-RDT was measured based on testing once, twice (after 48-hours), and thrice (after 96 hours). Analysis was repeated for different Days Post Index PCR Positivity (DPIPP) and stratified based on symptom-status.

Results

In total, 5,609 of 7,361 participants were eligible for this analysis. Among 154 participants who tested positive for SARS-CoV-2, 97 were asymptomatic and 57 had symptoms at infection onset. Serial testing with Ag-RDT twice 48-hours apart resulted in an aggregated sensitivity of 93.4% (95% CI: 89.1-96.1%) among symptomatic participants on DPIPP 0-6. Excluding singleton positives, aggregated sensitivity on DPIPP 0-6 for two-time serial-testing among asymptomatic participants was lower at 62.7% (54.7-70.0%) but improved to 79.0% (71.0-85.3%) with testing three times at 48-hour intervals.

Discussion

Performance of Ag-RDT was optimized when asymptomatic participants tested three-times at 48-hour intervals and when symptomatic participants tested two-times separated by 48-hours.

Finding a Needle in a Haystack: Design and Implementation of a Digital Site-less Clinical Study of Serial Rapid Antigen Testing to Identify Asymptomatic SARS-CoV-2 Infection

Background

Rapid antigen tests (Ag-RDT) for SARS-CoV-2 with Emergency Use Authorization generally include a condition of authorization to evaluate the test's performance in asymptomatic individuals when used serially.

Objective

To describe a novel study design to generate regulatory-quality data to evaluate serial use of Ag-RDT in detecting SARS-CoV-2 virus among asymptomatic individuals.

Design

Prospective cohort study using a decentralized approach. Participants were asked to test using Ag-RDT and molecular comparators every 48 hours for 15 days.

Setting

Participants throughout the mainland United States were enrolled through a digital platform between October 18, 2021 and February 15, 2022. Ag-RDTs were completed at home, and molecular comparators were shipped to a central laboratory.

Participants

Individuals over 2 years old from across the U.S. with no reported COVID-19 symptoms in the 14 days prior to study enrollment were eligible to enroll in this study.

Measurements

Enrollment demographics, geographic distribution, and SARS-CoV-2 infection rates are reported.

Key Results

A total of 7,361 participants enrolled in the study, and 492 participants tested positive for SARS-CoV-2, including 154 who were asymptomatic and tested negative to start the study. This exceeded the initial enrollment goals of 60 positive participants. We enrolled participants from 44 U.S. states, and geographic distribution of participants shifted in accordance with the changing COVID-19 prevalence nationwide.

Limitations

New, complex workflows required significant operational and data team support. Conclusions: The digital site-less approach employed in the 'Test Us At Home' study enabled rapid, efficient, and rigorous evaluation of rapid diagnostics for COVID-19, and can be adapted across research disciplines to optimize study enrollment and accessibility.

Comparison of Rapid Antigen Tests' Performance Between Delta and Omicron Variants of SARS-CoV-2 : A Secondary Analysis From a Serial Home Self-testing Study

BACKGROUND

It is important to document the performance of rapid antigen tests (Ag-RDTs) in detecting SARS-CoV-2 variants.

OBJECTIVE

To compare the performance of Ag-RDTs in detecting the Delta (B.1.617.2) and Omicron (B.1.1.529) variants of SARS-CoV-2.

DESIGN

Secondary analysis of a prospective cohort study that enrolled participants between 18 October 2021 and 24 January 2022. Participants did Ag-RDTs and collected samples for reverse transcriptase polymerase chain reaction (RT-PCR) testing every 48 hours for 15 days.

SETTING

The parent study enrolled participants throughout the mainland United States through a digital platform. All participants self-collected anterior nasal swabs for rapid antigen testing and RT-PCR testing. All Ag-RDTs were completed at home, whereas nasal swabs for RT-PCR were shipped to a central laboratory.

PARTICIPANTS

Of 7349 participants enrolled in the parent study, 5779 asymptomatic persons who tested negative for SARS-CoV-2 on day 1 of the study were eligible for this substudy.

MEASUREMENTS

Sensitivity of Ag-RDTs on the same day as the first positive (index) RT-PCR result and 48 hours after the first positive RT-PCR result.

RESULTS

A total of 207 participants were positive on RT-PCR (58 Delta, 149 Omicron). Differences in sensitivity between variants were not statistically significant (same day: Delta, 15.5% [95% CI, 6.2% to 24.8%] vs. Omicron, 22.1% [CI, 15.5% to 28.8%]; at 48 hours: Delta, 44.8% [CI, 32.0% to 57.6%] vs. Omicron, 49.7% [CI, 41.6% to 57.6%]). Among 109 participants who had RT-PCR-positive results for 48 hours, rapid antigen sensitivity did not differ significantly between Delta- and Omicron-infected participants (48-hour sensitivity: Delta, 81.5% [CI, 66.8% to 96.1%] vs. Omicron, 78.0% [CI, 69.1% to 87.0%]). Only 7.2% of the 69 participants with RT-PCR-positive results for shorter than 48 hours tested positive by Ag-RDT within 1 week; those with Delta infections remained consistently negative on Ag-RDTs.

LIMITATION

A testing frequency of 48 hours does not allow a finer temporal resolution of the analysis of test performance, and the results of Ag-RDTs are based on self-report.

CONCLUSION

The performance of Ag-RDTs in persons infected with the SARS-CoV-2 Omicron variant is not inferior to that in persons with Delta infections. Serial testing improved the sensitivity of Ag-RDTs for both variants. The performance of rapid antigen testing varies on the basis of duration of RT-PCR positivity.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute of the National Institutes of Health.

Feasibility of At-Home Serial Testing Using Over-the-Counter SARS-CoV-2 Tests With a Digital Smartphone App for Assistance: Longitudinal Cohort Study

BACKGROUND

The ongoing SARS-CoV-2 pandemic necessitates the development of accurate, rapid, and affordable diagnostics to help curb disease transmission, morbidity, and mortality. Rapid antigen tests are important tools for scaling up testing for SARS-CoV-2; however, little is known about individuals' use of rapid antigen tests at home and how to facilitate the user experience.

OBJECTIVE

This study aimed to describe the feasibility and acceptability of serial self-testing with rapid antigen tests for SARS-CoV-2, including need for assistance and the reliability of self-interpretation.

METHODS

A total of 206 adults in the United States with smartphones were enrolled in this single-arm feasibility study in February and March 2021. All participants were asked to self-test for COVID-19 at home using rapid antigen tests daily for 14 days and use a smartphone app for testing assistance and to report their results. The main outcomes were adherence to the testing schedule, the acceptability of testing and smartphone app experiences, and the reliability of participants versus study team's interpretation of test results. Descriptive statistics were used to report the acceptability, adherence, overall rating, and experience of using the at-home test and MyDataHelps app. The usability, acceptability, adherence, and quality of at-home testing were analyzed across different sociodemographic, age, and educational attainment groups.

RESULTS

Of the 206 enrolled participants, 189 (91.7%) and 159 (77.2%) completed testing and follow-up surveys, respectively. In total, 51.3% (97/189) of study participants were women, the average age was 40.7 years, 34.4% (65/189) were non-White, and 82% (155/189) had a bachelor's degree or higher. Most (n=133/206, 64.6%) participants showed high testing adherence, meaning they completed over 75% of the assigned tests. Participants' interpretations of test results demonstrated high agreement (2106/2130, 98.9%) with the study verified results, with a κ score of 0.29 (P<.001). Participants reported high satisfaction with self-testing and the smartphone app, with 98.7% (157/159) reporting that they would recommend the self-test and smartphone app to others. These results were consistent across age, race/ethnicity, and gender.

CONCLUSIONS

Participants' high adherence to the recommended testing schedule, significant reliability between participants and study staff's test interpretation, and the acceptability of the smartphone app and self-test indicate that self-tests for SARS-CoV-2 with a smartphone app for assistance and reporting is a highly feasible testing modality among a diverse population of adults in the United States.

Longitudinal Analysis of SARS-CoV-2 Vaccine Breakthrough Infections Reveals Limited Infectious Virus Shedding and Restricted Tissue Distribution

Background

The global effort to vaccinate people against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during an ongoing pandemic has raised questions about how vaccine breakthrough infections compare with infections in immunologically naive individuals and the potential for vaccinated individuals to transmit the virus.

Methods

We examined viral dynamics and infectious virus shedding through daily longitudinal sampling in 23 adults infected with SARS-CoV-2 at varying stages of vaccination, including 6 fully vaccinated individuals.

Results

The durations of both infectious virus shedding and symptoms were significantly reduced in vaccinated individuals compared with unvaccinated individuals. We also observed that breakthrough infections are associated with strong tissue compartmentalization and are only detectable in saliva in some cases.

Conclusions

Vaccination shortens the duration of time of high transmission potential, minimizes symptom duration, and may restrict tissue dissemination.

Daily longitudinal sampling of SARS-CoV-2 infection reveals substantial heterogeneity in infectiousness

The dynamics of SARS-CoV-2 replication and shedding in humans remain poorly understood. We captured the dynamics of infectious virus and viral RNA shedding during acute infection through daily longitudinal sampling of 60 individuals for up to 14 days. By fitting mechanistic models, we directly estimated viral expansion and clearance rates and overall infectiousness for each individual. Significant person-to-person variation in infectious virus shedding suggests that individual-level heterogeneity in viral dynamics contributes to 'superspreading'. Viral genome loads often peaked days earlier in saliva than in nasal swabs, indicating strong tissue compartmentalization and suggesting that saliva may serve as a superior sampling site for early detection of infection. Viral loads and clearance kinetics of Alpha (B.1.1.7) and previously circulating non-variant-of-concern viruses were mostly indistinguishable, indicating that the enhanced transmissibility of this variant cannot be explained simply by higher viral loads or delayed clearance. These results provide a high-resolution portrait of SARS-CoV-2 infection dynamics and implicate individual-level heterogeneity in infectiousness in superspreading.

Comparison of Rapid Antigen Tests' Performance between Delta (B.1.61.7; AY.X) and Omicron (B.1.1.529; BA1) Variants of SARS-CoV-2: Secondary Analysis from a Serial Home Self-Testing Study

Background

There is a need to understand the performance of rapid antigen tests (Ag-RDT) for detection of the Delta (B.1.61.7; AY.X) and Omicron (B.1.1.529; BA1) SARS-CoV-2 variants.

Methods

Participants without any symptoms were enrolled from October 18, 2021 to January 24, 2022 and performed Ag-RDT and RT-PCR tests every 48 hours for 15 days. This study represents a non-pre-specified analysis in which we sought to determine if sensitivity of Ag-RDT differed in participants with Delta compared to Omicron variant. Participants who were positive on RT-PCR on the first day of the testing period were excluded. Delta and Omicron variants were defined based on sequencing and date of first RT-PCR positive result (RT-PCR+). Comparison of Ag-RDT performance between the variants was based on sensitivity, defined as proportion of participants with Ag-RDT+ results in relation to their first RT-PCR+ result, for different duration of testing with rapid Ag-RDT. Subsample analysis was performed based on the result of participants' second RT-PCR test within 48 hours of the first RT-PCR+ test.

Results

From the 7,349 participants enrolled in the parent study, 5,506 met the eligibility criteria for this analysis. A total of 153 participants were RT-PCR+ (61 Delta, 92 Omicron); among this group, 36 (23.5%) tested Ag-RDT+ on the same day, and 84 (54.9%) tested Ag-RDT+ within 48 hours as first RT-PCR+. The differences in sensitivity between variants were not statistically significant (same-day: Delta 16.4% [95% CI: 8.2-28.1] vs Omicron 28.2% [95% CI: 19.4-38.6]; and 48-hours: Delta 45.9% [33.1-59.2] vs. Omicron 60.9% [50.1-70.9]). This trend continued among the 86 participants who had consecutive RT-PCR+ result (48-hour sensitivity: Delta 79.3% [60.3-92.1] vs. Omicron: 89.5% [78.5-96.0]). Conversely, the 38 participants who had an isolated RT-PCR+ remained consistently negative on Ag-RDT, regardless of the variant.

Conclusions

The performance of Ag-RDT is not inferior among individuals infected with the SARS-CoV-2 Omicron variant as compared to the Delta variant. The improvement in sensitivity of Ag-RDT noted with serial testing is consistent between Delta and Omicron variant. Performance of Ag-RDT varies based on duration of RT-PCR+ results and more studies are needed to understand the clinical and public health significance of individuals who are RT-PCR+ for less than 48 hours.

Longitudinal Assessment of Diagnostic Test Performance Over the Course of Acute SARS-CoV-2 Infection

BACKGROUND

Serial screening is critical for restricting spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by facilitating timely identification of infected individuals to interrupt transmission. Variation in sensitivity of different diagnostic tests at different stages of infection has not been well documented.

METHODS

In a longitudinal study of 43 adults newly infected with SARS-CoV-2, all provided daily saliva and nasal swabs for quantitative reverse transcription polymerase chain reaction (RT-qPCR), Quidel SARS Sofia antigen fluorescent immunoassay (FIA), and live virus culture.

RESULTS

Both RT-qPCR and Quidel SARS Sofia antigen FIA peaked in sensitivity during the period in which live virus was detected in nasal swabs, but sensitivity of RT-qPCR tests rose more rapidly prior to this period. We also found that serial testing multiple times per week increases the sensitivity of antigen tests.

CONCLUSIONS

RT-qPCR tests are more effective than antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (given timely results reporting). All tests showed >98% sensitivity for identifying infected individuals if used at least every 3 days. Daily screening using antigen tests can achieve approximately 90% sensitivity for identifying infected individuals while they are viral culture positive.

Longitudinal analysis of SARS-CoV-2 vaccine breakthrough infections reveal limited infectious virus shedding and restricted tissue distribution

The global effort to vaccinate people against SARS-CoV-2 in the midst of an ongoing pandemic has raised questions about the nature of vaccine breakthrough infections and the potential for vaccinated individuals to transmit the virus. These questions have become even more urgent as new variants of concern with enhanced transmissibility, such as Delta, continue to emerge. To shed light on how vaccine breakthrough infections compare with infections in immunologically naive individuals, we examined viral dynamics and infectious virus shedding through daily longitudinal sampling in a small cohort of adults infected with SARS-CoV-2 at varying stages of vaccination. The durations of both infectious virus shedding and symptoms were significantly reduced in vaccinated individuals compared with unvaccinated individuals. We also observed that breakthrough infections are associated with strong tissue compartmentalization and are only detectable in saliva in some cases. These data indicate that vaccination shortens the duration of time of high transmission potential, minimizes symptom duration, and may restrict tissue dissemination.

Daily sampling of early SARS-CoV-2 infection reveals substantial heterogeneity in infectiousness

The dynamics of SARS-CoV-2 replication and shedding in humans remain poorly understood. We captured the dynamics of infectious virus and viral RNA shedding during acute infection through daily longitudinal sampling of 60 individuals for up to 14 days. By fitting mechanistic models, we directly estimate viral reproduction and clearance rates, and overall infectiousness for each individual. Significant person-to-person variation in infectious virus shedding suggests that individual-level heterogeneity in viral dynamics contributes to superspreading. Viral genome load often peaked days earlier in saliva than in nasal swabs, indicating strong compartmentalization and suggesting that saliva may serve as a superior sampling site for early detection of infection. Viral loads and clearance kinetics of B.1.1.7 and non-B.1.1.7 viruses in nasal swabs were indistinguishable, however B.1.1.7 exhibited a significantly slower pre-peak growth rate in saliva. These results provide a high-resolution portrait of SARS-CoV-2 infection dynamics and implicate individual-level heterogeneity in infectiousness in superspreading.

A Mother's Story, Mitogenome Relationships in the Genus Rupicapra

Simple Summary

Two species of chamois (Rupicapra rupicapra and R. pyrenaica) are currently recognized by taxonomy and further subdivided into seven and three subspecies, respectively. However, recent research based on molecular markers finds this classification questionable. We aim to increase the resolution of published research on chamois phylogeny by including mitogenomes of all available subspecies, including the previously unpublished mitogenomes of R. r. balcanica and R. r. tatrica subspecies. The inferred phylogeny based on the full mitogenomes confirms the previously reported genus subdivision in three clades and its monophyletic positioning within the Caprinae. Phylogeny and taxonomy of Rupicapra species thus remain controversial prompting for the inclusion of archeological remains to solve the controversy.

Abstract

Although the two species of chamois (Rupicapra rupicapra and R. pyrenaica) are currently classified as least-concern by the IUCN (International Union for Conservation of Nature), inconsistencies on the subspecies classification reported in literature make it challenging to assess the conservation status of the single subspecies. Previous studies relying on mitochondrial genes, sometimes in combination with nuclear or Y-chromosome markers, reported the presence of clusters corresponding to the geographic distribution but highlighting ambiguities in the genus phylogeny. Here we report novel de novo assembled sequences of the mitochondrial genome from nine individuals, including previously unpublished R. r. balcanica and R. r. tatrica subspecies, and use them to untangle the genus phylogeny. Our results based on the full mitogenome inferred phylogeny confirm the previously reported genus subdivision in three clades and its monophyletic positioning within the Caprinae. Phylogeny and taxonomy of Rupicapra species thus remain controversial prompting for the inclusion of archeological remains to solve the controversy.

Longitudinal assessment of diagnostic test performance over the course of acute SARS-CoV-2 infection

What is already known about this topic?

Diagnostic tests and sample types for SARS-CoV-2 vary in sensitivity across the infection period.

What is added by this report?

We show that both RTqPCR (from nasal swab and saliva) and the Quidel SARS Sofia FIA rapid antigen tests peak in sensitivity during the period in which live virus can be detected in nasal swabs, but that the sensitivity of RTqPCR tests rises more rapidly in the pre-infectious period. We also use empirical data to estimate the sensitivities of RTqPCR and antigen tests as a function of testing frequency.

What are the implications for public health practice?

RTqPCR tests will be more effective than rapid antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (provided results reporting is timely). All modalities, including rapid antigen tests, showed >94% sensitivity to detect infection if used at least twice per week. Regular surveillance/screening using rapid antigen tests 2-3 times per week can be an effective strategy to achieve high sensitivity (>95%) for identifying infected individuals.

Observations on autochtonous liver flukes in wild ruminants in Slovakia

The aim of the study was monitoring of liver flukes in wild ruminants including red deer (Cervus elaphus), roe deer (Capreolus capreolus), fallow deer (Dama dama) and mouflon (Ovis musimon) in selected regions of Slovak Republic. Between 2014 – 2016 we examined 782 faecal samples from selected wild ruminants using coprological techniques and serological methods (ELISA detection of F. hepatica coproantigens). None of the samples was positive for the presence of Fasciola hepatica, 5.89 % of faecal samples were positive for Dicrocoelium dendriticum. Higher prevalence was recorded in mouflon (30.83 %), lower in red deer (1.49 %). D. dendriticum infection was not determined in fallow deer and roe deer. The seasonal distribution of dicrocoeliosis indicated a highest prevalence in autumn. Significantly higher prevalence was recorded in fenced rearing when compared with open hunting grounds, suggesting that animal agglomeration, constant use of the same areas and possible stress are the main risk factors. Parasitological examination of livers of hunted wild ruminants revealed dicrocoeliosis in mouflon.

A Study of Fish Lice (Argulus Sp.) Infection in Freshwater Food Fish

Argulus sp., commonly referred to as fish lice, are crustacean ectoparasites of fishes. The hematophagous parasites attach to and feed off the integument of their hosts. Outbreaks of epizootics have been reported worldwide, causing mass mortalities and having serious economic implications for fish farms and culture efforts. Argulus fish lice may also serve as vectors of infectious diseases and as intermediate hosts of other parasites. Two native European species, A. foliaceus and A. coregoni, as well as the invasive Japanese fish louse A. japonicus, have previously been recorded in Slovakia. This study investigated samples collected at fish farms and culture sites of Common carp (Cyprinus carpio L.), Pike-perch (Sander lucioperca L.) and Brook trout (Salvelinus fontinalis M.) in Eastern Slovakia, as well as samples collected from live fish imported to the Slovak Republic. A quantitative description of the of Argulus sp. was recorded from each locality. Samples from Common carp were identified as the invasive A. japonicus, and samples from Pike-perch and Brook trout were identified as A. foliaceus. Evidence of a mixed infection of Pike-perch with both A. foliaceus and A. japonicus was found in samples from Zemplínska Šírava, which was substantiated by electron microscopic examination. Morphometric characteristics were measured and averages and ranges produced for each species and sex.

Survival and Differentiation of Human Embryonic Stem Cell-Derived Neural Precursors Grafted Spinally in Spinal Ischemia-Injured Rats or in Naive Immunosuppressed Minipigs: A Qualitative and Quantitative Study

In previous studies, we have demonstrated that spinal grafting of human or rat fetal spinal neural precursors leads to amelioration of spasticity and improvement in ambulatory function in rats with spinal ischemic injury. In the current study, we characterize the survival and maturation of three different human embryonic stem (ES) cell line-derived neural precursors (hNPCs) once grafted into ischemia-injured lumbar spinal cord in rats or in naive immunosuppressed minipigs. Proliferating HUES-2, HUES-7, or HUES-9 colonies were induced to form embryoid bodies. During the nestin-positive stage, the rosettes were removed and CD184+/CD271-/CD44-/CD24+ population of ES-hNPCs FAC-sorted and expanded. Male Sprague–Dawley rats with spinal ischemic injury or naive immunosuppressed Gottingen–Minnesota minipigs received 10 bilateral injections of ES-NPCs into the L2–L5 gray matter. After cell grafting, animals survived for 2 weeks to 4.5 months, and the presence of grafted cells was confirmed after staining spinal cord sections with a combination of human-specific (hNUMA, HO14, hNSE, hSYN) or nonspecific (DCX, MAP2, CHAT, GFAP, APC) antibodies. In the majority of grafted animals, hNUMA-positive grafted cells were identified. At 2–4 weeks after grafting, double-labeled hNUMA/ DCX-immunoreactive neurons were seen with extensive DCX+ processes. At survival intervals of 4–8 weeks, hNSE+ neurons and expression of hSYN was identified. Some hSYN-positive terminals formed putative synapses with the host neurons. Quantitative analysis of hNUMA+ cells at 2 months after grafting showed comparable cell survival for all three cell lines. In the presence of low-level immunosuppression, no grafted cell survival was seen at 4.5 months after grafting. Spinal grafting of proliferating pluripotent HUES-7 cells led to consistent teratoma formation at 2–6 weeks after cell transplantation. These data show that ES-derived, FAC-sorted NPCs can represent an effective source of human NPCs to be used in CNS cell replacement therapies.

Combinational spinal GAD65 gene delivery and systemic GABA-mimetic treatment for modulation of spasticity

Background

Loss of GABA-mediated pre-synaptic inhibition after spinal injury plays a key role in the progressive increase in spinal reflexes and the appearance of spasticity. Clinical studies show that the use of baclofen (GABA_B receptor agonist), while effective in modulating spasticity is associated with major side effects such as general sedation and progressive tolerance development. The goal of the present study was to assess if a combined therapy composed of spinal segment-specific upregulation of GAD65 (glutamate decarboxylase) gene once combined with systemic treatment with tiagabine (GABA uptake inhibitor) will lead to an antispasticity effect and whether such an effect will only be present in GAD65 gene over-expressing spinal segments.

Methods/Principal Findings

Adult Sprague-Dawley (SD) rats were exposed to transient spinal ischemia (10 min) to induce muscle spasticity. Animals then received lumbar injection of HIV1-CMV-GAD65 lentivirus (LVs) targeting ventral α-motoneuronal pools. At 2–3 weeks after lentivirus delivery animals were treated systemically with tiagabine (4, 10, 20 or 40 mg/kg or vehicle) and the degree of spasticity response measured. In a separate experiment the expression of GAD65 gene after spinal parenchymal delivery of GAD65-lentivirus in naive minipigs was studied. Spastic SD rats receiving spinal injections of the GAD65 gene and treated with systemic tiagabine showed potent and tiagabine-dose-dependent alleviation of spasticity. Neither treatment alone (i.e., GAD65-LVs injection only or tiagabine treatment only) had any significant antispasticity effect nor had any detectable side effect. Measured antispasticity effect correlated with increase in spinal parenchymal GABA synthesis and was restricted to spinal segments overexpressing GAD65 gene.

Conclusions/Significance

These data show that treatment with orally bioavailable GABA-mimetic drugs if combined with spinal-segment-specific GAD65 gene overexpression can represent a novel and highly effective anti-spasticity treatment which is associated with minimal side effects and is restricted to GAD65-gene over-expressing spinal segments.

Chronic spinal compression model in minipigs: a systematic behavioral, qualitative, and quantitative neuropathological study

The goal of the present study was to develop a porcine spinal cord injury (SCI) model, and to describe the neurological outcome and characterize the corresponding quantitative and qualitative histological changes at 4-9 months after injury. Adult Gottingen-Minnesota minipigs were anesthetized and placed in a spine immobilization frame. The exposed T12 spinal segment was compressed in a dorso-ventral direction using a 5-mm-diameter circular bar with a progressively increasing peak force (1.5, 2.0, or 2.5 kg) at a velocity of 3 cm/sec. During recovery, motor and sensory function were periodically monitored. After survival, the animals were perfusion fixed and the extent of local SCI was analyzed by (1) post-mortem MRI analysis of dissected spinal cords, (2) qualitative and quantitative analysis of axonal survival at the epicenter of injury, and (3) defining the presence of local inflammatory changes, astrocytosis, and schwannosis. Following 2.5-kg spinal cord compression the animals demonstrated a near complete loss of motor and sensory function with no recovery over the next 4-9 months. Those that underwent spinal cord compression with 2 kg force developed an incomplete injury with progressive partial neurological recovery characterized by a restricted ability to stand and walk. Animals injured with a spinal compression force of 1.5 kg showed near normal ambulation 10 days after injury. In fully paralyzed animals (2.5 kg), MRI analysis demonstrated a loss of spinal white matter integrity and extensive septal cavitations. A significant correlation between the magnitude of loss of small and medium-sized myelinated axons in the ventral funiculus and neurological deficits was identified. These data, demonstrating stable neurological deficits in severely injured animals, similarities of spinal pathology to humans, and relatively good post-injury tolerance of this strain of minipigs to spinal trauma, suggest that this model can successfully be used to study therapeutic interventions targeting both acute and chronic stages of SCI.

Assessing statistical significance in microarray experiments using the distance between microarrays

We propose permutation tests based on the pairwise distances between microarrays to compare location, variability, or equivalence of gene expression between two populations. For these tests the entire microarray or some pre-specified subset of genes is the unit of analysis. The pairwise distances only have to be computed once so the procedure is not computationally intensive despite the high dimensionality of the data. An R software package, permtest, implementing the method is freely available from the Comprehensive R Archive Network at http://cran.r-project.org.

Protein A/G dependent ELISA a promising diagnostic tool in Lyme disease seroprevalence in game animals and hunting dogs

One of the major problems in serodiagnosis in wild animals is unavailability of specific antiglobulin conjugate. Our study focuses on validation of Protein A/G dependent ELISA in game animals like deer and mouflons as well as in hunting dogs. Binding ability of Protein A/G-conjugate to antibodies was the highest in dogs followed by fallow deer and mouflons. Three different whole cell Borrelia antigens were used to evaluate antigen dependent variation. In new Protein A/G-ELISA the highest sensitivities (90.50%, deer; 85.37%, mouflon & 94.29%, dog) were obtained by B. garinii antigen, with no statistically significant variation (chi(2), P>0.05) among all other antigens used. Average seroprevalences observed in deer, mouflons and dogs were 44.90%, 29.41% and 30.43%, respectively. Marked influence of age on seroprevalence was noticed. Protein A/G-ELISA proved to be sensitive and promising diagnostic tool in serodiagnosis of Lyme disease in game ungulates and it can be used effectively for serosurvey in different wild mammals.

Probing the cysteine-34 position of endogenous serum albumin with thiol-binding doxorubicin derivatives. Improved efficacy of an acid-sensitive doxorubicin derivative with specific albumin-binding properties compared to that of the parent compound

We have recently proposed a macromolecular prodrug strategy for improved cancer chemotherapy based on two features (Kratz, F.; et al. J. Med. Chem 2000, 43, 1253-1256.): (a) rapid and selective binding of thiol-reactive prodrugs to the cysteine-34 position of endogenous albumin after intravenous administration and (b) release of the albumin-bound drug in the acidic environment at the tumor site due to the incorporation of an acid-sensitive bond between the drug and the carrier. To investigate this therapeutic strategy in greater depth, four (maleinimidoalkanoyl)hydrazone derivatives of doxorubicin were synthesized differing in the length of the aliphatic spacer (1, -(CH(2))(2)-; 2, -(CH(2))(3)-; 3, -(CH(2))(5)-; 4, -(CH(2))(7)-). The albumin-binding doxorubicin prodrugs, especially the (6-maleimidocaproyl)hydrazone derivative of doxorubicin (3), are rapidly and selectively bound to the cysteine-34 position of endogenous albumin. 3 was distinctly superior to the parent compound doxorubicin in three animal tumor models (RENCA, MDA-MB 435, and MCF-7) with respect to antitumor efficacy and toxicity.

Development and in vitro efficacy of novel MMP2 and MMP9 specific doxorubicin albumin conjugates

Two doxorubicin albumin conjugates (A-DP1 and A-DP2), which differ in their substrate specificity for the matrix metalloproteinases MMP2 and MMP9, were prepared by binding maleimide doxorubicin peptide derivatives to the cysteine-34 position of human serum albumin. The incorporated octapeptide, Gly-Pro-Gln-Arg-Ile-Ala-Gly-Gln, in A-DP2 is not cleaved by activated MMP2 and MMP9 in contrast to Gly-Pro-Leu-Gly-Ile-Ala-Gly-Gln incorporated in A-DP1 that is cleaved efficiently by activated MMP2 and MMP9 liberating a doxorubicin tetrapeptide. A-DP1 showed antiproliferative activity in a murine renal cell carcinoma line in the low micromolar range (IC(50) value approximately 0.2 microM).

[Follicular maturation, dizygotic twin conceptions and maternal age]

This note aims to given an interpretation of the "paradoxical" increase of dizygotic twin pregnancies (and more generally of multiple pregnancies) according to maternal age, when in parallel the number of growing follicles decreases strongly. From the analysis, through an allometric model, of the relative variations with age of the size of the various ovarian follicular compartments, it reinforces the hypothesis of the existence of an inhibition factor, whose level would depend on the size of the residual stock of follicles and which would act on one or several phases of the follicular development. It brings evidence for the major role that this factor might play in the regulation of the whole reproductive life of women (and probably other mammals).

Marker-derived phylogeny of European cattle supports demic expansion of agriculture

Using frequencies of 86 genes from 23 loci of blood group systems, blood and milk proteins, the genetic relationships among 14 cattle breeds including four native Balkan and four synthetic Balkan-Alp breeds were studied. The dendrogram and nonlinear map construction shows a consensus 'Balkan breed cluster', an 'Alp breed cluster', an unstable position of synthetic breeds and well-separated American breeds. Positive partial correlations between genetic distance and time elapsed since introduction of farming while keeping geographical distances constant, and regular patterns over thousands of kilometers indicate that large-scale cattle population movements together with human migration (in the Neolithic age) from the Near East into Europe across the Balkans are the most likely explanation for the genetic distances observed in our data. More recent breed differentiation and selection do not yet blur this initial pattern of European cattle populations.

The action of calcitonin gene-related peptide on astrocyte morphology and cyclic AMP accumulation in astrocyte cultures from neonatal rat brain

The actions of calcitonin gene-related peptide (CGRP) were investigated on 9- to 14-day-old astrocyte cultures obtained from the cerebra of 1- to 2-day-old rats. The morphological appearance of the cells was monitored by immunofluorescent staining of glial fibrillary acidic protein (GFAP), and the concentration of adenosine 3',5'-monophosphate (cyclic AMP) was measured in the cultures using radioimmunoassay. CGRP induced a morphological change in cultured astrocytes from rat brain. Flat, polygonal cells positive for GFAP became multipolar with many processes. In addition, CGRP stimulated the accumulation of cyclic AMP by up to 30-fold, half maximal stimulation being obtained at CGRP concentrations in the range 100-300 nM. These data provide evidence for the presence of functional CGRP receptors on astrocytes and suggest a role for CGRP as an intercellular messenger controlling the state of differentiation and activation of astroglial cells.

Dry skin, water, and lubrication

Lubrication of the skin will become more important as our population ages. Many excellent moisturizers are available for lubrication. Individual ingredients that are touted heavily are not as important as the total mixture. The single most important factor is the regular use of the products to prevent overdrying of the skin. How should we use this information to achieve our aims? 1. The frequency of bathing, showering, and cleansing should be reduced. The water should be kept at the coolest temperature practical, and one should get out as soon as possible. Sponge bathing should be encouraged. Bath oils make tubs slippery and are wiped off by towels. It is better to apply an emollient directly on skin that is still damp. 2. Room temperatures should be kept low and comfortable and humidity should be kept as high as possible without causing damage. 3. Overdrying should be avoided by limiting the exposure to soap, detergents, solvents, and water. In addition, friction from washcloths, rough clothing, and abrasives should be avoided. 4. Emollients should be used frequently and selected to be compatible with the individual's situation. Bedridden individuals should use petrolatum, whereas the ambulatory would be better served by the use of lotions and creams. 5. If itching is present or reticulated cracking (eczema craquelé) is seen, more aggressive treatment is indicated, including possible use of topical steroid preparations. 6. A preparation that is cosmetically acceptable, so that it will be used regularly, should be prescribed. One must emphasize its importance so that the individual avoids serious and chronic dermatitis.

[Preliminary results of noncontact temperature measuring using an infrared thermometer on the tarsus pf swine with osteoarthrosis tarsi deformans]

The surface temperature on tarsus of 54 performance tested boars of about 60 kg of Swedish Landrace was measured by means of infra-red thermometer at three measuring points (MP1, MP2 and MP3). MP1 was situated above the tuberculum of os metatarsale III or, as visualised in 21 slaughtered boars, above pathoanatomical alterations of osteoarthrosis tarsi deformans (OATD). MP2 was located directly medially and MP3 laterally from MP1. A clear palpatory symptom was found only with 10 boars, while all 21 slaughtered boars showed different morphological lesions of OATD. The average temperature at MP1 was 35.69 degrees C and was significantly higher (P = .01) than at MP2 (35.34) and MP3 (35.30). The temperature differences between MP1 and MP2 or MP3 were statistically reliable. Boars, who had a clear palpatory symptoms at tuberculum, showed an average temperature at MT1 of 36.27 degrees C, which was higher (P = .0114) than of those with an unclear palpatory symptom (35.64 degrees C). The results show that the temperature differences are the consequence of OATD.

Streaky pigmentation in a patient with acquired immune deficiency syndrome (AIDS)

We report a case of hyperpigmentation due to bleomycin treatment in a patient with acquired immune deficiency syndrome (AIDS). Although this type of hyperpigmentation has been previously seen in patients with cancer who are receiving bleomycin, this is, to our knowledge, the first reported case of bleomycin-induced hyperpigmentation in an AIDS patient and should be added to the growing list of cutaneous eruptions seen in these patients.

An unanticipated use of a topical cream

A sixteen-year-old black male, distraught over his acne, injected his face via syringe and needle with a topical cream. Within twelve hours, the injected lesions became red and edematous, and later tender. After treatment with oral prednisone and erythromycin, the lesions resolved. This case serves to illustrate the unexpected misuses of cosmetics, in this instance, a patient anxious only to improve his acne problem.

Epidemiologic investigation of respiratory effects related to environmental exposure to asbestos inside insulated buildings

The respiratory effects of environmental pollution by asbestos inside university buildings were studied by comparing radiographic, clinical, and functional parameters among three groups of workers with different levels of exposure. Eight hundred and twenty-eight (828) people who worked for at least 15 yr in asbestos-insulated buildings and who were without known occupational exposure to asbestos (environmentally exposed group [EE]) were compared to a group of 252 workers with occupational exposure (occupationally exposed group [OE]), used as positive control; and to a group of 350 people with no known exposure to asbestos (nonexposed group [NE]), within the same university. After adjustment for confounding variables, no differences could be seen between groups EE and NE. Group OE exhibited a higher prevalence of pleural changes and lower lung functions than groups EE and NE.

Cosmetics, Barnum, and science

The marketing and use of cosmetics can involve consumers, government regulators, and dermatologists. As practitioners, we should be aware of these interactions and of the role cosmetics play in the lives of our patients, in the marketplace, and in society as a whole.

Assessment of exposure to lead of the general population in the French community through biological monitoring

The aim of the council directive of 29 March 1977 of the European Community (1) is the screening for non-work-related lead exposure levels in the general populations of European (member) countries. In France, such testing was carried out in eight metropolitan areas (having more than 500,000 inhabitants), another eight "critical" areas surrounding industrial emission sources and one area (Vosges) having a high level of lead contamination in the water. In view of the reference values (maximum 35 micrograms/dl in an individual blood sample) adopted by the directive, the situation is most serious in the area where the exposure is due to the lead contamination in the water. Individuals here run a seven times greater risk of exceeding the 35 micrograms/dl blood-lead limit relative to urban populations where the lead comes mostly from vehicle emissions into the atmosphere (i.e. 9.3% of the blood-lead values of the Vosgian sample exceed 35 micrograms/dl; 3.5% for the industrial complexes which deal with lead and 1.4% for the urban zone). While these vehicle exhausts are the subject of much current concern, in perspective, the problem of lead pipe contaminated drinking water appears to be of far greater importance.

Algorithm for the grouping of contiguous geographical zones

In geographical epidemiology, the correlation between two variables is often studied, using as basic units those zones for which these variables are available. However, because of their geographical contiguity, it could be misleading to consider each of these zones as independent statistical units. Moreover, spatial distributions (either of the factor or of the disease) are often distributed in relatively simple patterns; these patterns may induce strong correlations. Thus, the general pattern of the spatial distribution of the variables should be investigated before any attempt to infer epidemiological interpretation of a relationship. This paper presents an algorithm to construct contiguous groupings which are similar enough with regard to one of the two variables considered and to thus divide the original set of geographical areas into contrasting zones. The algorithm is easy to compute and allows mapping of the geographical distribution of the variable studied. It also lessens the risk of duplication of basic information by reducing the autocorrelation of one of the variables.