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1.
iScience ; 27(4): 109569, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38623329

ABSTRACT

Preeclampsia (PE) is a hypertensive pregnancy disorder with increased risk of maternal and fetal morbidity and mortality. Abnormal extravillous trophoblast (EVT) development and function is considered to be the underlying cause of PE, but has not been previously modeled in vitro. We previously derived induced pluripotent stem cells (iPSCs) from placentas of PE patients and characterized abnormalities in formation of syncytiotrophoblast and responses to changes in oxygen tension. In this study, we converted these primed iPSC to naïve iPSC, and then derived trophoblast stem cells (TSCs) and EVT to evaluate molecular mechanisms underlying PE. We found that primed (but not naïve) iPSC-derived PE-EVT have reduced surface HLA-G, blunted invasive capacity, and altered EVT-specific gene expression. These abnormalities correlated with promoter hypermethylation of genes associated with the epithelial-mesenchymal transition pathway, specifically in primed-iPSC derived PE-EVT. Our findings indicate that abnormal epigenetic regulation might play a role in PE pathogenesis.

2.
Curr Opin Physiol ; 352023 Oct.
Article in English | MEDLINE | ID: mdl-37873030

ABSTRACT

Endothelial caveolae are essential for a wide range of physiological processes and have emerged as key players in vascular biology. Our understanding of caveolar biology in endothelial cells has expanded dramatically since their discovery revealing critical roles in mechanosensation, signal transduction, eNOS regulation, lymphatic transport, and metabolic disease progression. Furthermore, caveolae are involved in the organization of membrane domains, regulation of membrane fluidity, and endocytosis which contribute to endothelial function and integrity. Additionally, recent advances highlight the impact of caveolae-mediated signaling pathways on vascular homeostasis and pathology. Together, the diverse roles of caveolae discussed here represent a breadth of cellular functions presenting caveolae as a defining feature of endothelial form and function. In light of these new insights, targeting caveolae may hold potential for the development of novel therapeutic strategies to treat a range of vascular diseases.

3.
PLoS One ; 17(11): e0277420, 2022.
Article in English | MEDLINE | ID: mdl-36378663

ABSTRACT

Helminth infections are cryptic and can be difficult to study in wildlife species. Helminth research in wildlife hosts has historically required invasive animal handling and necropsy, while results from noninvasive parasite research, like scat analysis, may not be possible at the helminth species or individual host levels. To increase the utility of noninvasive sampling, individual hosts can be identified by applying molecular methods. This allows for longitudinal sampling of known hosts and can be paired with individual-level covariates. Here we evaluate a combination of methods and existing long-term monitoring data to identify patterns of cestode infections in gray wolves in Yellowstone National Park. Our goals were: (1) Identify the species and apparent prevalence of cestodes infecting Yellowstone wolves; (2) Assess the relationships between wolf biological and social characteristics and cestode infections; (3) Examine how wolf samples were affected by environmental conditions with respect to the success of individual genotyping. We collected over 200 wolf scats from 2018-2020 and conducted laboratory analyses including individual wolf genotyping, sex identification, cestode identification, and fecal glucocorticoid measurements. Wolf genotyping success rate was 45%, which was higher in the winter but decreased with higher precipitation and as more time elapsed between scat deposit and collection. One cestode species was detected in 28% of all fecal samples, and 38% of known individuals. The most common infection was Echinococcus granulosus sensu lato (primarily E. canadensis). Adult wolves had 4x greater odds of having a cestode infection than pups, as well as wolves sampled in the winter. Our methods provide an alternative approach to estimate cestode prevalence and to linking parasites to known individuals in a wild host system, but may be most useful when employed in existing study systems and when field collections are designed to minimize the time between fecal deposition and collection.


Subject(s)
Cestoda , Cestode Infections , Helminths , Parasites , Wolves , Animals , Wolves/parasitology , Prevalence , Cestode Infections/epidemiology , Cestode Infections/veterinary , Cestode Infections/parasitology
4.
Stem Cell Reports ; 17(6): 1303-1317, 2022 06 14.
Article in English | MEDLINE | ID: mdl-35594858

ABSTRACT

Trophoblast stem cells (TSCs) have recently been derived from human embryos and early-first-trimester placenta; however, aside from ethical challenges, the unknown disease potential of these cells limits their scientific utility. We have previously established a bone morphogetic protein 4 (BMP4)-based two-step protocol for differentiation of primed human pluripotent stem cells (hPSCs) into functional trophoblasts; however, those trophoblasts could not be maintained in a self-renewing TSC-like state. Here, we use the first step from this protocol, followed by a switch to newly developed TSC medium, to derive bona fide TSCs. We show that these cells resemble placenta- and naive hPSC-derived TSCs, based on their transcriptome as well as their in vitro and in vivo differentiation potential. We conclude that primed hPSCs can be used to generate functional TSCs through a simple protocol, which can be applied to a widely available set of existing hPSCs, including induced pluripotent stem cells, derived from patients with known birth outcomes.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Cell Differentiation , Female , Humans , Placenta , Pregnancy , Trophoblasts
5.
Clin Appl Thromb Hemost ; 27: 10760296211018510, 2021.
Article in English | MEDLINE | ID: mdl-34047195

ABSTRACT

Uncontrolled bleeding associated with trauma and surgery is the leading cause of preventable death. Batroxobin, a snake venom-derived thrombin-like serine protease, has been shown to clot fibrinogen by cleaving fibrinopeptide A in a manner distinctly different from thrombin, even in the presence of heparin. The biochemical properties of batroxobin and its effect on coagulation have been well characterized in vitro. However, the efficacy of batroxobin on hemostatic clot formation in vivo is not well studied due to the lack of reliable in vivo hemostasis models. Here, we studied the efficacy of batroxobin and slounase, a batroxobin containing activated factor X, on hemostatic clot composition and bleeding using intravital microcopy laser ablation hemostasis models in micro and macro vessels and liver puncture hemostasis models in normal and heparin-induced hypocoagulant mice. We found that prophylactic treatment in wild-type mice with batroxobin, slounase and activated factor X significantly enhanced platelet-rich fibrin clot formation following vascular injury. In heparin-treated mice, batroxobin treatment resulted in detectable fibrin formation and a modest increase in hemostatic clot size, while activated factor X had no effect. In contrast, slounase treatment significantly enhanced both platelet recruitment and fibrin formation, forming a stable clot and shortening bleeding time and blood loss in wild-type and heparin-treated hypocoagulant mice. Our data demonstrate that, while batroxobin enhances fibrin formation, slounase was able to enhance hemostasis in normal mice and restore hemostasis in hypocoagulant conditions via the enhancement of fibrin formation and platelet activation, indicating that slounase is more effective in controlling hemorrhage.


Subject(s)
Batroxobin/therapeutic use , Blood Coagulation Tests/methods , Blood Coagulation/drug effects , Hemorrhage/drug therapy , Hemostatics/therapeutic use , Animals , Batroxobin/pharmacology , Hemostatics/pharmacology , Humans , Male , Mice
6.
Int J Pharm Pract ; 27(5): 408-423, 2019 Oct.
Article in English | MEDLINE | ID: mdl-30964225

ABSTRACT

OBJECTIVES: Potentially inappropriate medication (PIM) use in older adults is a prevalent problem associated with poor health outcomes. Understanding drivers of PIM use is essential for targeting interventions. This study systematically reviews the literature about the patient, clinician and environmental/system factors associated with PIM use in community-dwelling older adults in the United States. METHODS: PRISMA guidelines were followed when completing this review. PubMed and EMBASE were queried from January 2006 to September 2017. Our search was limited to English-language studies conducted in the United States that assessed factors associated with PIM use in adults ≥65 years who were community-dwelling. Two independent reviewers screened titles and abstracts. Reviewers abstracted data sequentially and assessed risk of bias independently. KEY FINDINGS: Twenty-two studies were included. Nineteen examined patient factors associated with PIM use. The most common statistically significant factors associated with PIM use were taking more medications, female sex, and higher outpatient and emergency department utilization. Only three studies examined clinician factors, and few were statistically significant. Fifteen studies examined system-level factors such as geographic region and health insurance. The most common statistically significant association was the south and west geographic region relative to the northeast United States. CONCLUSIONS: Amongst older adults, women and persons on more medications are at higher risk of PIM use. There is evidence that increased healthcare use is also associated with PIM use. Future studies are needed exploring clinician factors, such as specialty, and their association with PIM prescribing.


Subject(s)
Inappropriate Prescribing/prevention & control , Independent Living , Potentially Inappropriate Medication List/statistics & numerical data , Aged , Aged, 80 and over , Female , Humans , Inappropriate Prescribing/statistics & numerical data , Male , Polypharmacy , Sex Factors , United States
7.
PLoS One ; 14(4): e0214823, 2019.
Article in English | MEDLINE | ID: mdl-30947305

ABSTRACT

REDD+ projects primarily focus on reducing carbon emissions from deforestation and forest degradation in developing countries. These projects are regularly evaluated against their core objective of conserving carbon stocks, but their contribution to biodiversity conservation has rarely been assessed. To assess the conservation value of the area and the relative performance of a REDD+ land use plan in Yaeda Valley, a semi-arid savannah ecosystem in northern Tanzania, we implemented an annual wildlife monitoring scheme. Based on direct sightings and indirect signs of wildlife, obtained from stratified walking transects conducted annually from 2015-2018, we estimated annual trends of mammal species richness and wildlife densities in three REDD+ and three non-REDD+ land-use strata. Our surveys document a near complete mammal community in the area. Species accumulation curves, and subsequent statistical comparisons, indicated highest mammal species richness in the woodland habitats (both REDD+ and non REDD+ strata) as compared to more human and livestock impacted areas, and suggested constant species richness from 2015-2018. To estimate stratum- and year-specific livestock and wildlife densities (cattle, donkey, goat and sheep combined, Thomson's gazelle, Kirk's dik-dik) and wildlife sign densities (aardvark, bushbuck, bushpig, Kirk's dik dik, eland, elephant, Maasai giraffe, greater kudu, hyena, impala, lesser kudu, warthog, wildebeest, Plains zebra), we fitted species-specific detection functions in a distance sampling framework. Species-specific densities varied between 2015 and 2018 and showed substantial increases and occasional declines in other species-stratum combinations. However, population growth rates were not systematically associated with specific land-use strata. Although our results do not explicitly provide evidence that REDD+ land-use plans directly co-benefit wildlife conservation, they show that REDD+ areas have the potential to maintain intact wildlife assemblages. To ensure effective long-term conservation outcomes, we advocate for a more formal integration of wildlife conservation goals in the REDD+ scheme.


Subject(s)
Animals, Wild , Conservation of Natural Resources/methods , Animals , Biodiversity , Carbon , Ecosystem , Environmental Monitoring , Forests , Humans , Livestock , Mammals , Natural Resources , Population Dynamics , Species Specificity , Tanzania
8.
Thromb Res ; 171: 155-159, 2018 11.
Article in English | MEDLINE | ID: mdl-30312801

ABSTRACT

INTRODUCTION: Recent genome wide association studies (GWAS) identified a novel susceptibility locus for thrombosis, harbouring the SLC44A2 gene which encodes the Solute Carrier Family 44 Member 2 protein (SLC44A2). Thus far, SLC44A2 has not been studied in the context of thrombosis, and may be a unique contributor to thrombotic disease. Here we utilize mice lacking SLC44A2 (Slc44a2-/-) to evaluate a possible role of SLC44A2 in hemostasis. METHODS: Slc44a2-/- mice were evaluated in key aspects of normal hemostasis including a challenge of vascular damage by applying laser induced injury to the cremaster muscle arteriole. RESULTS: Slc44a2-/- mice had comparable levels of thrombin generation and gene expression of coagulation related genes, as compared to littermate wild type controls. Lower levels of circulating plasma Von Willebrand factor (VWF) were measured in Slc44a2-/- mice, while no difference in VWF multimerization or vascular localization was detected. Upon in vivo laser injury of the cremaster arterioles, we detected an impairment of clot formation for Slc44a2-/- mice. CONCLUSIONS: Although mice lacking SLC44A2 are normal for several hemostasis parameters, we do observe a reduction of plasma VWF levels and an altered response upon vascular damage, which suggests that SLC44A2 contributes to hemostasis upon injury. These findings are in line with the reported GWAS data and support further research on SLC44A2 in thrombosis.


Subject(s)
Gene Deletion , Hemostasis , Membrane Transport Proteins/genetics , Thrombosis/genetics , Animals , Female , Genome-Wide Association Study , Male , Mice , Mice, Inbred C57BL , Thrombosis/blood , von Willebrand Factor/analysis
9.
Urol Oncol ; 35(11): 647-658, 2017 11.
Article in English | MEDLINE | ID: mdl-28943200

ABSTRACT

BACKGROUND: The overuse of radiologic services, where imaging tests are provided in circumstances where the propensity for harm exceeds the propensity for benefit, comprises a risk to patient safety and a burden on health care systems. Advanced imaging in the staging of low-risk prostate cancer is considered an overused procedure by many professional societies, yet the determinants that drive this phenomenon are not fully appreciated. METHODS: We systematically searched published literature within MEDLINE and Embase from January 1998 to March 2017. We searched for studies conducted in the United States that contain original data and describe determinants associated with the overuse of imaging in low-risk prostate cancer. Paired reviewers independently screened abstracts, assessed quality, and extracted data. We synthesized the identified determinants as patient-level, clinician-level, or system-level factors of overuse. RESULTS: A total of 14 articles were included; the 13 empirical studies defined overuse as being the use of imaging that was discordant with clinical guidelines. Patient- and system-related factors were most commonly described as being associated with overuse; clinician-level determinants were examined infrequently. Older patient age (n = 5), more patient comorbidities (n = 7), and characteristics related to geography (n = 6), higher regional income (n = 6), and less education (n = 5) were the most consistently identified statistically significant determinants of overuse. Meaningful differences were detected between health care settings; large integrated health care systems provided less variable care and had lower rates of overuse. Clinical indicators related to prostate cancer were inconsistently associated with overuse. CONCLUSION: Many patient- and system-related determinants were identified as contributing to the overuse of advanced imaging to stage low-risk prostate cancer. Overuse may be the consequence of systematized clinician behavior and be relatively invariant of patient characteristics. The identified system-level determinants suggest that payment models that are not tied to volume or that reward, enhanced care co-ordination may curb overuse. We propose further examination of physician-level determinants and implore researchers to rank the relative importance of the identified factors and to test their influence through experimental and quasi-experimental methods.


Subject(s)
Diagnostic Imaging/methods , Prostate/diagnostic imaging , Prostatic Neoplasms/diagnostic imaging , Delivery of Health Care/standards , Diagnostic Imaging/adverse effects , Diagnostic Imaging/standards , Humans , Male , Prostate/pathology , Quality of Health Care/standards
10.
J Am Med Dir Assoc ; 18(9): 806.e1-806.e17, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28764876

ABSTRACT

BACKGROUND: Potentially inappropriate medications (PIMs) are widely used in institutionalized older adults, yet the key determinants that drive their use are incompletely characterized. METHODS: We systematically searched published literature within MEDLINE and Embase from January 1998 to March 2017. We searched for studies conducted in the United States that described determinants of PIM use in adults ≥60 years of age in a nursing home or residential care facility, in the emergency department (ED), or in the hospital. Paired reviewers independently screened abstracts and full-text articles, assessed quality, and extracted data. RESULTS: Among 30 included articles, 12 examined PIM use in the nursing home or residential care settings, 4 in the ED, 12 in acute care hospitals, and 2 across settings. The Beers criteria were most frequently used to identify PIM use, which ranged from 3.6% to 92.0%. Across all settings, the most common determinants of PIM use were medication burden and geographic region. In the nursing home, the most common additional determinants were younger age, and diagnoses of depression or diabetes. In both the ED and hospital, patients receiving care in the West, Midwest, and South, relative to the Northeast, were at greater risk of receiving a PIM. Very few studies examined clinician determinants of PIM use; geriatricians used fewer PIMs in the hospital than other clinicians. CONCLUSIONS: Among older adults, those who are on many medications are at increased risk for PIM use across multiple settings. We propose that careful testing of interventions that target modifiable determinants are indicated to assess their impact on PIM use.


Subject(s)
Clinical Decision-Making , Inappropriate Prescribing , Nursing Homes , Female , Humans , Long-Term Care , Male
11.
JMIR Res Protoc ; 5(2): e56, 2016 May 06.
Article in English | MEDLINE | ID: mdl-27153752

ABSTRACT

BACKGROUND: Clinical decision support (CDS), including computerized reminders for providers and patients, can improve health outcomes. CDS promoting influenza vaccination, delivered directly to patients via an electronic health record (EHR) patient portal and interactive voice recognition (IVR) calls, offers an innovative approach to improving patient care. OBJECTIVE: To test the effectiveness of an EHR patient portal and IVR outreach to improve rates of influenza vaccination in a large multispecialty group practice in central Massachusetts. METHODS: We describe a nonblinded, randomized controlled trial of EHR patient portal messages and IVR calls designed to promote influenza vaccination. In our preparatory phase, we conducted qualitative interviews with patients, providers, and staff to inform development of EHR portal messages with embedded questionnaires and IVR call scripts. We also provided practice-wide education on influenza vaccines to all physicians and staff members, including information on existing vaccine-specific EHR CDS. Outreach will target adult patients who remain unvaccinated for more than 2 months after the start of the influenza season. Using computer-generated randomization and a factorial design, we will assign 20,000 patients who are active users of electronic patient portals to one of the 4 study arms: (1) receipt of a portal message promoting influenza vaccines and offering online appointment scheduling; (2) receipt of an IVR call with similar content but without appointment facilitation; (3) both (1) and (2); or (4) neither (1) nor (2) (usual care). We will randomize patients without electronic portals (10,000 patients) to (1) receipt of IVR call or (2) usual care. Both portal messages and IVR calls promote influenza vaccine completion. Our primary outcome is percentage of eligible patients with influenza vaccines administered at our group practice during the 2014-15 influenza season. Both outreach methods also solicit patient self-report on influenza vaccinations completed outside the clinic or on barriers to influenza vaccination. Self-reported data from both outreach modes will be uploaded into the EHR to increase accuracy of existing provider-directed EHR CDS (vaccine alerts). RESULTS: With our proposed sample size and using a factorial design, power calculations using baseline vaccination rate estimates indicated that 4286 participants per arm would give 80% power to detect a 3% improvement in influenza vaccination rates between groups (α=.05; 2-sided). Intention-to-treat unadjusted chi-square analyses will be performed to assess the impact of portal messages, either alone or in combination with the IVR call, on influenza vaccination rates. The project was funded in January 2014. Patient enrollment for the project described here completed in December 2014. Data analysis is currently under way and first results are expected to be submitted for publication in 2016. CONCLUSIONS: If successful, this study's intervention may be adapted by other large health care organizations to increase vaccination rates among their eligible patients. CLINICALTRIAL: ClinicalTrials.gov NCT02266277; https://clinicaltrials.gov/ct2/show/NCT02266277 (Archived by WebCite at http://www.webcitation.org/6fbLviHLH).

12.
Patient Educ Couns ; 99(10): 1685-93, 2016 10.
Article in English | MEDLINE | ID: mdl-27067065

ABSTRACT

OBJECTIVE: To describe surrogate decision makers' (SDMs) perspectives on preventable breakdowns in care among critically ill patients. METHODS: We screened 70 SDMs of critically ill patients for those who identified a preventable breakdown in care, defined as an event where the SDM believes something "went wrong", that could have been prevented, and resulted in harm. In-depth interviews were conducted with SDMs who identified an eligible event. RESULTS: 32 of 70 participants (46%) identified at least one preventable breakdown in care, with a total of 75 discrete events. Types of breakdowns involved medical care (n=52), communication (n=59), and both (n=40). Four additional breakdowns were related to problems with SDM bedside access to the patient. Adverse consequences of breakdowns included physical harm, need for additional medical care, emotional distress, pain, suffering, loss of trust, life disruption, impaired decision making, and financial expense. 28 of 32 SDMs raised their concerns with clinicians, yet only 25% were satisfactorily addressed. CONCLUSION: SDMs of critically ill patients frequently identify preventable breakdowns in care which result in harm. PRACTICE IMPLICATIONS: An in-depth understanding of the types of events SDMs find problematic and the associated harms is an important step towards improving the safety and patient-centeredness of healthcare.


Subject(s)
Communication , Critical Illness , Decision Making , Medical Errors/prevention & control , Professional-Family Relations , Adult , Continuity of Patient Care , Critical Illness/therapy , Female , Humans , Intensive Care Units , Interviews as Topic , Male , Massachusetts , Middle Aged , Patient Safety , Qualitative Research
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