14 research outputs found
Hybridization in parasites: consequences for adaptive evolution, pathogenesis and public health in a changing world
[No abstract available
Blending of animal colour patterns by hybridization
Biologists have long been fascinated by the amazing diversity of animal colour patterns. Despite much interest, the underlying evolutionary and developmental mechanisms contributing to their rich variety remain largely unknown, especially the vivid and complex colour patterns seen in vertebrates. Here, we show that complex and camouflaged animal markings can be formed by the 'blending' of simple colour patterns. A mathematical model predicts that crossing between animals having inverted spot patterns (for example, 'light spots on a dark background' and 'dark spots on a light background') will necessarily result in hybrid offspring that have camouflaged labyrinthine patterns as 'blended' intermediate phenotypes. We confirmed the broad applicability of the model prediction by empirical examination of natural and artificial hybrids of salmonid fish. Our results suggest an unexplored evolutionary process by means of 'pattern blending', as one of the possible mechanisms underlying colour pattern diversity and hybrid speciation
Addressing the disparities in dementia risk, early detection and care in Latino populations: Highlights from the Second Latinos and Alzheimer's Symposium
The Alzheimer's Association hosted the second Latinos & Alzheimer's Symposium in May 2021. Due to the COVID-19 pandemic, the meeting was held online over 2 days, with virtual presentations, discussions, mentoring sessions, and posters. The Latino population in the United States is projected to have the steepest increase in Alzheimer's disease (AD) in the next 40 years, compared to other ethnic groups. Latinos have increased risk for AD and other dementias, limited access to quality care, and are severely underrepresented in AD and dementia research and clinical trials. The symposium highlighted developments in AD research with Latino populations, including advances in AD biomarkers, and novel cognitive assessments for Spanish-speaking populations, as well as the need to effectively recruit and retain Latinos in clinical research, and how best to deliver health-care services and to aid caregivers of Latinos living with AD
Effects of Cu/Zn Superoxide Dismutase (sod1) Genotype and Genetic Background on Growth, Reproduction and Defense in Biomphalaria glabrata
Resistance of the snail Biomphalaria glabrata to the trematode Schistosoma mansoni is correlated with allelic variation at copper-zinc superoxide dismutase (sod1). We tested whether there is a fitness cost associated with carrying the most resistant allele in three outbred laboratory populations of snails. These three populations were derived from the same base population, but differed in average resistance. Under controlled laboratory conditions we found no cost of carrying the most resistant allele in terms of fecundity, and a possible advantage in terms of growth and mortality. These results suggest that it might be possible to drive resistant alleles of sod1 into natural populations of the snail vector for the purpose of controlling transmission of S. mansoni. However, we did observe a strong effect of genetic background on the association between sod1 genotype and resistance. sod1 genotype explained substantial variance in resistance among individuals in the most resistant genetic background, but had little effect in the least resistant genetic background. Thus, epistatic interactions with other loci may be as important a consideration as costs of resistance in the use of sod1 for vector manipulation
Prediction of Opioid-Induced Respiratory Depression on Inpatient Wards Using Continuous Capnography and Oximetry: An International Prospective, Observational Trial.
BACKGROUND: Opioid-related adverse events are a serious problem in hospitalized patients. Little is known about patients who are likely to experience opioid-induced respiratory depression events on the general care floor and may benefit from improved monitoring and early intervention. The trial objective was to derive and validate a risk prediction tool for respiratory depression in patients receiving opioids, as detected by continuous pulse oximetry and capnography monitoring.
METHODS: PRediction of Opioid-induced respiratory Depression In patients monitored by capnoGraphY (PRODIGY) was a prospective, observational trial of blinded continuous capnography and oximetry conducted at 16 sites in the United States, Europe, and Asia. Vital signs were intermittently monitored per standard of care. A total of 1335 patients receiving parenteral opioids and continuously monitored on the general care floor were included in the analysis. A respiratory depression episode was defined as respiratory rate ≤5 breaths/min (bpm), oxygen saturation ≤85%, or end-tidal carbon dioxide ≤15 or ≥60 mm Hg for ≥3 minutes; apnea episode lasting \u3e30 seconds; or any respiratory opioid-related adverse event. A risk prediction tool was derived using a multivariable logistic regression model of 46 a priori defined risk factors with stepwise selection and was internally validated by bootstrapping.
RESULTS: One or more respiratory depression episodes were detected in 614 (46%) of 1335 general care floor patients (43% male; mean age, 58 ± 14 years) continuously monitored for a median of 24 hours (interquartile range [IQR], 17-26). A multivariable respiratory depression prediction model with area under the curve of 0.740 was developed using 5 independent variables: age ≥60 (in decades), sex, opioid naivety, sleep disorders, and chronic heart failure. The PRODIGY risk prediction tool showed significant separation between patients with and without respiratory depression (P \u3c .001) and an odds ratio of 6.07 (95% confidence interval [CI], 4.44-8.30; P \u3c .001) between the high- and low-risk groups. Compared to patients without respiratory depression episodes, mean hospital length of stay was 3 days longer in patients with ≥1 respiratory depression episode (10.5 ± 10.8 vs 7.7 ± 7.8 days; P \u3c .0001) identified using continuous oximetry and capnography monitoring.
CONCLUSIONS: A PRODIGY risk prediction model, derived from continuous oximetry and capnography, accurately predicts respiratory depression episodes in patients receiving opioids on the general care floor. Implementation of the PRODIGY score to determine the need for continuous monitoring may be a first step to reduce the incidence and consequences of respiratory compromise in patients receiving opioids on the general care floor
Mate choice drives evolutionary stability in a hybrid complex
Previous studies have shown that assortative mating acts as a driver of speciation by countering
hybridization between two populations of the same species (pre-zygotic isolation) or
through mate choice among the hybrids (hybrid speciation). In both speciation types, assortative
mating promotes speciation over a transient hybridization stage. We studied mate
choice in a hybrid vertebrate complex, the allopolyploid fish Squalius alburnoides. This complex
is composed by several genomotypes connected by an intricate reproductive dynamics.
We developed a model that predicts the hybrid complex can persist when females
exhibit particular mate choice patterns. Our model is able to reproduce the diversity of population
dynamic outcomes found in nature, namely the dominance of the triploids and the
dominance of the tetraploids, depending on female mate choice patterns and frequency of
the parental species. Experimental mate choice trials showed that females exhibit the preferences
predicted by the model. Thus, despite the known role of assortative mating in driving
speciation, our findings suggest that certain mate choice patterns can instead hinder
speciation and support the persistence of hybrids over time without speciation or extinction
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Pectoralis Plane Block for Pacemaker Insertion: A Successful Primary Anesthetic
Effective anesthesia, analgesia, and hemodynamic stability is important to maintain during pacemaker implantation surgery, especially in the elderly population and patients with compromised cardiac function. As a strategy to avoid the need for intravenous (IV) anesthetics, peripheral nerve block techniques may be used in these specific cases. We report a case of successful pacemaker implantation surgery in a patient with severe Aortic Stenosis (AS) and Sick Sinus Syndrome (SSS) using unilateral pectoralis plane block for surgical anesthesia. Since general anesthesia was considered risky, monitored anesthesia care utilizing peripheral nerve block was planned. A single shot left side pectoralis plane block (PECS II) was done under ultrasound guidance injecting a total of 20 mL of 0.5% Ropivacaine with 1% Lidocaine. No sedation was needed. The patient tolerated the procedure with no significant hemodynamic changes. Patient did not require opioids post-operative and was discharged home in stable condition the next day. This case highlights that PECS block can also provide effective surgical anesthesia for relatively long procedures avoiding the risk of complications associated with IV anesthesia in high risk cardiovascular patients. Additionally, these blocks can provide an opioid sparing option for post-operative management in pacemaker implantation surgeries
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Anesthetic Management for Pediatric Liver Transplantation in a Patient With Propionic Acidemia: A Case Report
Propionic acidemia is an inborn error of metabolism characterized by accumulation of propionic acid due to deficiency of propionyl-CoA carboxylase. Main stay of treatment focuses on reducing dietary protein. However, orthotropic liver transplantation decreases the frequency of metabolic decompensations and improves life expectancy. We report a case of a 4-year-old boy undergoing orthotropic liver transplantation to treat propionic acidemia. This case highlights the use of intraoperative monitoring of metabolic markers like urine ketones, arterial ammonia, and lactate levels as these patients are at risk for hyperammonemia and metabolic acidosis. Also, the relevance in outcomes when performing early extubation in fast-tracking recovery
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Addressing the disparities in dementia risk, early detection and care in Latino populations: Highlights from the second Latinos & Alzheimer's Symposium.
The Alzheimer's Association hosted the second Latinos & Alzheimer's Symposium in May 2021. Due to the COVID-19 pandemic, the meeting was held online over 2 days, with virtual presentations, discussions, mentoring sessions, and posters. The Latino population in the United States is projected to have the steepest increase in Alzheimer's disease (AD) in the next 40 years, compared to other ethnic groups. Latinos have increased risk for AD and other dementias, limited access to quality care, and are severely underrepresented in AD and dementia research and clinical trials. The symposium highlighted developments in AD research with Latino populations, including advances in AD biomarkers, and novel cognitive assessments for Spanish-speaking populations, as well as the need to effectively recruit and retain Latinos in clinical research, and how best to deliver health-care services and to aid caregivers of Latinos living with AD