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1.
Front Aging Neurosci ; 15: 1155630, 2023.
Article in English | MEDLINE | ID: mdl-37469955

ABSTRACT

Introduction: Aberrant activation of Extracellular Signal-Regulated Kinase (ERK) signaling is associated with Alzheimer's disease (AD) pathogenesis. For example, enhanced ERK signal activation mediated by Apolipoprotein E4 (APOE4), which is a critical genetic risk factor for AD, increases the transcription of amyloid precursor protein (APP). We hypothesize that O-linked N-acetylglucosamine (O-GlcNAc) regulates the phosphorylation and activation of ERK. O-GlcNAc is a single sugar post-translational modification that dynamically cycles on and off proteins in response to nutrient changes by the action of the enzymes O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively. However, O-GlcNAc quickly returns to a baseline level after stimulus removal (called O-GlcNAc homeostasis). Methods: We did a serum reactivation time-course followed by western blot in SH-SY5Y neuroblastoma cells after long-term O-GlcNAcase (OGA) inhibition by Thiamet-G (TMG) treatment, O-GlcNAc transferase (OGT) knock-down (KD) and OGA KD. Brain tissues of C57BL6/J mice and 5XFAD Alzheimer's disease mice intra-peritoneally injected with TMG for 1 month and C57BL6/J mice intra-peritoneally injected with TMG for 6 months were also used for western blot. Results: We found that ERK1/2 phosphorylation at Thr 202/Tyr204 and Thr183/Tyr185 (p-ERK) are amplified and hence ERK1/2 are activated after long-term OGA inhibition in SH-SY5Y cells. In addition to pharmacological treatment, genetic disruption of O-GlcNAc by OGT KD and OGA KD also increased p-ERK in SH-SY5Y cells suggesting O-GlcNAc homeostasis controls ERK signaling. To determine how O-GlcNAc regulates p-ERK, we probed the expression of phosphorylated mitogen-activated protein kinase-kinase (p-MEK) which phosphorylates and activates ERK and Dual specificity phosphatase-4 (DUSP4) which dephosphorylates and inactivates ERK in SH-SY5Y cells. p-MEK increases in TMG treated and OGT KD cells whereas total DUSP4 decreases in OGT KD and OGA KD cells with serum reactivation time course. Next, we probed the role of OGA inhibition in regulating ERK activation using mice brain-tissue samples. Interestingly, 6-month intra-peritoneal TMG injection in C57BL/6J mice showed an increase in amplitude of p-ERK and APP protein levels, indicating long-term OGA inhibition potentially contributes to AD progression. Furthermore, 1-month TMG injection was sufficient to increase the amplitude of p-ERK in 5XFAD AD mice brains suggesting AD phenotype contributes to the acceleration of ERK activation mediated by OGA inhibition. Conclusion: Together, these results indicate that disruptions to O-GlcNAc homeostasis amplify ERK signal activation in AD.

3.
Front Sociol ; 8: 1191080, 2023.
Article in English | MEDLINE | ID: mdl-38328739

ABSTRACT

To what extent do Americans racially discriminate against doctors? While a large literature shows that racial biases pervade the American healthcare system, there has been no systematic examination of these biases in terms of who patients select for medical treatment. We examine this question in the context of the ongoing global COVID-19 pandemic, where a wealth of qualitative evidence suggests that discrimination against some historically marginalized communities, particularly Asians, has increased throughout the United States. Conducting a well-powered conjoint experiment with a national sample of 1,498 Americans, we find that respondents do not, on average, discriminate against Asian or doctors from other systematically minoritized groups. We also find no consistent evidence of treatment effect heterogeneity; Americans of all types appear not to care about the racial identity of their doctor, at least in our study. This finding has important implications for the potential limits of American prejudice.

7.
JAMA Dermatol ; 157(6): 716-720, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33978670

ABSTRACT

Importance: In response to the coronavirus disease 2019 (COVID-19) pandemic, 2 mRNA vaccines (Pfizer-BioNTech and Moderna) received emergency use authorization from the US Food and Drug Administration in December 2020. Some patients in the US have developed delayed localized cutaneous vaccine reactions that have been dubbed "COVID arm." Objective: To describe the course of localized cutaneous injection-site reactions to the Moderna COVID-19 vaccine, subsequent reactions to the second vaccine dose, and to characterize the findings of histopathologic examination of the reaction. Design, Setting, and Participants: This retrospective case series study was performed at Yale New Haven Hospital, a tertiary medical center in New Haven, Connecticut, with 16 patients referred with localized cutaneous injection-site reactions from January 20 through February 12, 2021. Main Outcomes and Measures: We collected each patient's demographic information, a brief relevant medical history, clinical course, and treatment (if any); and considered the findings of a histopathologic examination of 1 skin biopsy specimen. Results: Of 16 patients (median [range] age, 38 [25-89] years; 13 [81%] women), 14 patients self-identified as White and 2 as Asian. The delayed localized cutaneous reactions developed in a median (range) of 7 (2-12) days after receiving the Moderna COVID-19 vaccine. These reactions occurred at or near the injection site and were described as pruritic, painful, and edematous pink plaques. None of the participants had received the Pfizer-BioNTech vaccine. Results of a skin biopsy specimen demonstrated a mild predominantly perivascular mixed infiltrate with lymphocytes and eosinophils, consistent with a dermal hypersensitivity reaction. Of participants who had a reaction to first vaccine dose (15 of 16 patients), most (11 patients) developed a similar localized injection-site reaction to the second vaccine dose; most (10 patients) also developed the second reaction sooner as compared with the first-dose reaction. Conclusions and Relevance: Clinical and histopathologic findings of this case series study indicate that the localized injection-site reactions to the Moderna COVID-19 vaccine are a delayed hypersensitivity reaction. These reactions may occur sooner after the second dose, but they are self-limited and not associated with serious vaccine adverse effects. In contrast to immediate hypersensitivity reactions (eg, anaphylaxis, urticaria), these delayed reactions (dubbed "COVID arm") are not a contraindication to subsequent vaccination.


Subject(s)
COVID-19 Vaccines/adverse effects , COVID-19/prevention & control , Drug Eruptions/epidemiology , Injection Site Reaction/epidemiology , 2019-nCoV Vaccine mRNA-1273 , Adult , Aged , Aged, 80 and over , Connecticut/epidemiology , Drug Eruptions/diagnosis , Drug Eruptions/drug therapy , Drug Eruptions/immunology , Female , Histamine Antagonists/therapeutic use , Humans , Injection Site Reaction/diagnosis , Injection Site Reaction/drug therapy , Injection Site Reaction/immunology , Male , Middle Aged , Retrospective Studies , Skin/immunology , Skin/pathology
10.
Pediatr Dermatol ; 36(4): e91-e92, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30994203

ABSTRACT

Lichen aureus is a pigmented purpuric dermatosis that tends to occur on the lower extremities, and linear morphea is an inflammatory disease of the dermis and subcutaneous fat that leads to a scarlike induration. We present a pediatric case of linear morphea developing in the same anatomic distribution as prior lichen aureus. Due to the possible progression of lichen aureus to morphea described herein and the difficulty in diagnosing early morphea, close follow-up may be considered for pediatric patients who present with this pigmented purpuric dermatosis.


Subject(s)
Folic Acid/administration & dosage , Methotrexate/administration & dosage , Scleroderma, Localized/drug therapy , Scleroderma, Localized/pathology , Steroids/therapeutic use , Administration, Oral , Administration, Topical , Biopsy, Needle , Child , Diagnosis, Differential , Drug Therapy, Combination , Exanthema/diagnosis , Exanthema/etiology , Humans , Immunohistochemistry , Leg Dermatoses/diagnosis , Leg Dermatoses/etiology , Male , Prognosis , Pruritus/diagnosis , Pruritus/etiology , Scleroderma, Localized/complications , Scleroderma, Localized/diagnosis , Treatment Outcome
11.
AIDS Res Hum Retroviruses ; 30(11): 1017-22, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24857015

ABSTRACT

Empirical testing of candidate vaccines has led to the successful development of a number of lifesaving vaccines. The advent of new tools to manipulate antigens and new methods and vectors for vaccine delivery has led to a veritable explosion of potential vaccine designs. As a result, selection of candidate vaccines suitable for large-scale efficacy testing has become more challenging. This is especially true for diseases such as dengue, HIV, and tuberculosis where there is no validated animal model or correlate of immune protection. Establishing guidelines for the selection of vaccine candidates for advanced testing has become a necessity. A number of factors could be considered in making these decisions, including, for example, safety in animal and human studies, immune profile, protection in animal studies, production processes with product quality and stability, availability of resources, and estimated cost of goods. The "immune space template" proposed here provides a standardized approach by which the quality, level, and durability of immune responses elicited in early human trials by a candidate vaccine can be described. The immune response profile will demonstrate if and how the candidate is unique relative to other candidates, especially those that have preceded it into efficacy testing and, thus, what new information concerning potential immune correlates could be learned from an efficacy trial. A thorough characterization of immune responses should also provide insight into a developer's rationale for the vaccine's proposed mechanism of action. HIV vaccine researchers plan to include this general approach in up-selecting candidates for the next large efficacy trial. This "immune space" approach may also be applicable to other vaccine development endeavors where correlates of vaccine-induced immune protection remain unknown.


Subject(s)
Communicable Diseases/epidemiology , Drug Discovery/methods , Drug Discovery/standards , Vaccines/immunology , Vaccines/isolation & purification , Animals , Clinical Trials as Topic , Humans , Vaccination/methods , Vaccines/adverse effects
12.
Ann Bot ; 111(4): 629-39, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23404991

ABSTRACT

BACKGROUND AND AIMS: Crop models for herbaceous ornamental species typically include functions for temperature and photoperiod responses, but very few incorporate vernalization, which is a requirement of many traditional crops. This study investigated the development of floriculture crop models, which describe temperature responses, plus photoperiod or vernalization requirements, using Australian native ephemerals Brunonia australis and Calandrinia sp. METHODS: A novel approach involved the use of a field crop modelling tool, DEVEL2. This optimization program estimates the parameters of selected functions within the development rate models using an iterative process that minimizes sum of squares residual between estimated and observed days for the phenological event. Parameter profiling and jack-knifing are included in DEVEL2 to remove bias from parameter estimates and introduce rigour into the parameter selection process. KEY RESULTS: Development rate of B. australis from planting to first visible floral bud (VFB) was predicted using a multiplicative approach with a curvilinear function to describe temperature responses and a broken linear function to explain photoperiod responses. A similar model was used to describe the development rate of Calandrinia sp., except the photoperiod function was replaced with an exponential vernalization function, which explained a facultative cold requirement and included a coefficient for determining the vernalization ceiling temperature. Temperature was the main environmental factor influencing development rate for VFB to anthesis of both species and was predicted using a linear model. CONCLUSIONS: The phenology models for B. australis and Calandrinia sp. described development rate from planting to VFB and from VFB to anthesis in response to temperature and photoperiod or vernalization and may assist modelling efforts of other herbaceous ornamental plants. In addition to crop management, the vernalization function could be used to identify plant communities most at risk from predicted increases in temperature due to global warming.


Subject(s)
Flowers/growth & development , Magnoliopsida/physiology , Models, Biological , Photoperiod , Linear Models , Portulacaceae/physiology , Temperature , Time Factors
14.
Ann Bot ; 108(1): 215-20, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21586530

ABSTRACT

BACKGROUND AND AIMS: The time at which plants are transferred to floral inductive conditions affects the onset of flowering and plant morphology, due to juvenility. Plants of Brunonia australis and Calandrinia sp. were used to investigate whether Australian native ephemeral species show a distinct juvenile phase that can be extended to increase vegetative growth and flowering. METHODS: The juvenile phase was quantified by transferring seedlings from less inductive (short day and 30/20°C) to inductive (vernalization or long day) conditions at six different plant ages ranging from 4 to 35 d after seed germination. An increase in days to first visible floral bud and leaf number were used to signify the end of juvenility. KEY RESULTS: Brunonia australis was receptive to floral inductive long day conditions about 18-22 d after seed germination, whereas plants aged 4-35 d appeared vernalization sensitive. Overall, transferring plants of B. australis from short to long day conditions reduced the time to anthesis compared with vernalization or constant short day conditions. Calandrinia sp. showed a facultative requirement for vernalization and an insensitive phase was not detected. Floral bud and branch production increased favourably as plant age at time of transfer to inductive conditions increased. Younger plants showed the shortest crop production time. CONCLUSIONS: Both species can perceive the vernalization floral stimulus from a very young age, whereas the photoperiodic stimulus is perceived by B. australis after a period of vegetative growth. However, extending the juvenile phase can promote foliage development and enhance flower production of both species.


Subject(s)
Flowers/growth & development , Magnoliopsida/growth & development , Photoperiod , Cold Temperature , Flowers/metabolism , Magnoliopsida/metabolism , Seasons , Time Factors
15.
Sci Transl Med ; 3(79): 79ps13, 2011 Apr 20.
Article in English | MEDLINE | ID: mdl-21508308

ABSTRACT

Developing a vaccine against the human immunodeficiency virus (HIV) poses an exceptional challenge. There are no documented cases of immune-mediated clearance of HIV from an infected individual, and no known correlates of immune protection. Although nonhuman primate models of lentivirus infection have provided valuable data about HIV pathogenesis, such models do not predict HIV vaccine efficacy in humans. The combined lack of a predictive animal model and undefined biomarkers of immune protection against HIV necessitate that vaccines to this pathogen be tested directly in clinical trials. Adaptive clinical trial designs can accelerate vaccine development by rapidly screening out poor vaccines while extending the evaluation of efficacious ones, improving the characterization of promising vaccine candidates and the identification of correlates of immune protection.


Subject(s)
AIDS Vaccines , Clinical Trials as Topic , HIV Infections/immunology , HIV Infections/prevention & control , HIV-1/immunology , Research Design , AIDS Vaccines/administration & dosage , AIDS Vaccines/immunology , Animals , Disease Models, Animal , Humans , Treatment Outcome
16.
Rural Remote Health ; 10(2): 1333, 2010.
Article in English | MEDLINE | ID: mdl-20568911

ABSTRACT

The Cree of Northern Ontario, Canada, have proved resilient and adaptable to social and environmental changes. However, the rapidity of climate change impacts in the Hudson Bay Lowlands of the Canadian sub-Arctic is challenging this resiliency. A collaborative project conducted with the Weenusk First Nation at Peawanuck and researchers at Lakehead University used the concept of wellbeing to explore the impact of climate change on current subsistence activities, resource management, and conservation strategies, while considering the implications of globalization on climate change awareness. This article describes the analysis of 22 interviews conducted with members of the Weenusk First Nation at Peawanuck. Findings indicate that residents are concerned with a variety of changes in the environment and their ability to use the land. For example, they noted changes in travel routes on water and land, often attributing these to geomorphic changes in the coastal landscapes along Hudson Bay. They also noted the disappearance of particular insects and bird species, and variations in the distribution of particular fauna and flora. Possible impacts of these changes on the community's wellbeing and resiliency are examined. Another major theme that arose from the analysis was the impact of traditional modes of communication (eg traditional knowledge, radio, newspaper) and newer forms (eg satellite television and the internet) on Indigenous people's understanding of climate change. Given that few researchers have acknowledged or recognized the globalization of the moccasin telegraph (ie the traditional mode of communication between First Nations), a discussion of this phenomenon and its significance for understanding emerging knowledge systems in small, remote First Nation communities is central to this article.


Subject(s)
Climate Change , Communication , Indians, North American , Social Change , Adult , Culture , Female , Food , Health Status , Humans , Interviews as Topic , Male , Middle Aged , Ontario , Rural Health , Technology
17.
BMC Public Health ; 9: 452, 2009 Dec 06.
Article in English | MEDLINE | ID: mdl-19961625

ABSTRACT

BACKGROUND: New Zealand rates of obesity and overweight have increased since the 1980s, particularly among indigenous Maori people, Pacific people and those living in areas of high deprivation. New Zealand's response to the obesity epidemic has been The Healthy Eating-Healthy Action: Oranga Kai - Oranga Pumau (HEHA) Strategy ('the Strategy'), launched in 2003. Because the HEHA Strategy explicitly recognises the importance of evaluation and the need to create an evidence base to support future initiatives, the Ministry of Health has commissioned a Consortium of researchers to evaluate the Strategy as a whole. METHODS: This paper discusses the Consortium's approach to evaluating the HEHA Strategy. It includes an outline of the conceptual framework underpinning the evaluation, and describes the critical components of the evaluation which are: judging to what extent stakeholders were engaged in the process of the strategy implementation and to what extent their feedback was incorporated in to future iterations of the Strategy (continuous improvement), to what extent the programmes, policies, and initiatives implemented span the target populations and priority areas, whether there have been any population changes in nutrition and/or physical activity outcomes or behaviours relating to those outcomes, and to what extent HEHA Strategy and spending can be considered value for money. DISCUSSION: This paper outlines our approach to evaluating a complex national health promotion strategy. Not only does the Evaluation have the potential to identify interventions that could be adopted internationally, but also the development of the Evaluation design can inform other complex evaluations.


Subject(s)
Diet , Health Promotion , Obesity/prevention & control , Primary Prevention/methods , Exercise , Health Plan Implementation , Health Services Research , Humans , New Zealand/epidemiology , Obesity/epidemiology , Outcome Assessment, Health Care
18.
N Z Med J ; 122(1289): 24-31, 2009 Feb 13.
Article in English | MEDLINE | ID: mdl-19305446

ABSTRACT

BACKGROUND: Liver transplantation (LT) is established treatment for adults and children with acute or chronic liver failure, however there are insufficient donor organs to meet demand and 14% of New Zealand patients have died waiting or were de-listed due to deterioration whilst on the waiting list. Live donor liver transplantation (LDLT) offers an alternative graft source that enables timely transplantation, but also carries the risk of morbidity and mortality for the donor. AIM: To report the initial experience with LDLT in New Zealand. METHODS: Review of donor and recipient outcomes for the first 20 cases. RESULTS: 129 potential live liver donors were assessed for 68 recipients. Donors were evaluated according to a multi-step protocol including independent donor advocacy. Twenty LDLT were performed on 7 adults and 13 paediatric recipients using 5 right lobe, 2 extended left lobe, 2 left lobe, and 11 left lateral section grafts. Five donors (25%) experienced postoperative complications, none of which were life-threatening. Four recipients had acute liver failure and 16 had chronic liver disease including one retransplant. There was a high rate of recipient biliary complications (40%) but graft and recipient survival is 100% to date. CONCLUSION: LDLT has been successfully introduced in New Zealand with good donor and recipient outcomes.


Subject(s)
Liver Transplantation/statistics & numerical data , Living Donors , Adult , Female , Humans , Length of Stay/statistics & numerical data , Liver Diseases/surgery , Male , Middle Aged , New Zealand , Postoperative Complications/epidemiology , Tissue and Organ Procurement/organization & administration , Treatment Outcome , Young Adult
20.
Science ; 321(5888): 530-2, 2008 Jul 25.
Article in English | MEDLINE | ID: mdl-18653883

ABSTRACT

The need to broaden research directed at answering fundamental questions in HIV vaccine discovery through laboratory, nonhuman primate (NHP), and clinical research has recently been emphasized. In addition, the importance of attracting and retaining young researchers, developing better NHP models, and more closely linking NHP and clinical research is being stressed. In an era of a level budget for biomedical research at the U.S. National Institutes of Health (NIH), HIV/AIDS vaccine research efforts will need to be carefully prioritized such that resources to energize HIV vaccine discovery can be identified. This article summarizes progress and challenges in HIV vaccine research, the priorities arising from a recent summit at NIAID, and the actions needed, some already under way, to address those priorities.


Subject(s)
AIDS Vaccines , Biomedical Research , HIV Infections/prevention & control , AIDS Vaccines/economics , AIDS Vaccines/immunology , Animals , Biomedical Research/economics , Controlled Clinical Trials as Topic , Disease Models, Animal , Financing, Government , HIV/immunology , HIV/physiology , HIV Antibodies/immunology , HIV Infections/immunology , HIV Infections/virology , Humans , Male , National Institute of Allergy and Infectious Diseases (U.S.)/economics , Primates , Research Support as Topic , T-Lymphocytes/immunology , United States , Virus Replication
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