ABSTRACT
Siberia has undergone dramatic climatic changes due to global warming in recent decades. Yet, the ecological responses to these climatic changes are still poorly understood due to a lack of data. Here, we use a unique data set from the Russian 'Chronicles of Nature' network to analyse the long-term (1976-2018) phenological shifts in leaf out, flowering, fruiting and senescence of 67 common Siberian plant species. We find that Siberian boreal forest plants advanced their early season (leaf out and flowering) and mid-season (fruiting) phenology by -2.2, -0.7 and -1.6 days/decade, and delayed the onset of senescence by 1.6 days/decade during this period. These mean values, however, are subject to substantial intraspecific variability, which is partly explained by the plants' growth forms. Trees and shrubs advanced leaf out and flowering (-3.1 and -3.3. days/decade) faster than herbs (-1 day/decade), presumably due to the more direct exposure of leaf and flower buds to ambient air for the woody vegetation. For senescence, we detected a reverse pattern: stronger delays in herbs (2.1 days/decade) than in woody plants (1.0-1.2 days/decade), presumably due to the stronger effects of autumn frosts on the leaves of herbs. Interestingly, the timing of fruiting in all four growth forms advanced at similar paces, from 1.4 days/decade in shrubs to 1.7 days/decade in trees and herbs. Our findings point to a strong, yet heterogeneous, response of Siberian plant phenology to recent global warming. Furthermore, the results highlight that species- and growth form-specific differences among study species could be used to identify plants particularly at risk of decline due to their low adaptive capacity or a loss of synchronization with important interaction partners.
Subject(s)
Climate Change , Trees , Global Warming , Plant Leaves , Seasons , TemperatureABSTRACT
BACKGROUND AND AIMS: Fruiting remains under-represented in long-term phenology records, relative to leaf and flower phenology. Herbarium specimens and historical field notes can fill this gap, but selecting and synthesizing these records for modern-day comparison requires an understanding of whether different historical data sources contain similar information, and whether similar, but not equivalent, fruiting metrics are comparable with one another. METHODS: For 67 fleshy-fruited plant species, we compared observations of fruiting phenology made by Henry David Thoreau in Concord, Massachusetts (1850s), with phenology data gathered from herbarium specimens collected across New England (mid-1800s to 2000s). To identify whether fruiting times and the order of fruiting among species are similar between datasets, we compared dates of first, peak and last observed fruiting (recorded by Thoreau), and earliest, mean and latest specimen (collected from herbarium records), as well as fruiting durations. KEY RESULTS: On average, earliest herbarium specimen dates were earlier than first fruiting dates observed by Thoreau; mean specimen dates were similar to Thoreau's peak fruiting dates; latest specimen dates were later than Thoreau's last fruiting dates; and durations of fruiting captured by herbarium specimens were longer than durations of fruiting observed by Thoreau. All metrics of fruiting phenology except duration were significantly, positively correlated within (r: 0.69-0.88) and between (r: 0.59-0.85) datasets. CONCLUSIONS: Strong correlations in fruiting phenology between Thoreau's observations and data from herbaria suggest that field and herbarium methods capture similar broad-scale phenological information, including relative fruiting times among plant species in New England. Differences in the timing of first, last and duration of fruiting suggest that historical datasets collected with different methods, scales and metrics may not be comparable when exact timing is important. Researchers should strongly consider matching methodology when selecting historical records of fruiting phenology for present-day comparisons.
Subject(s)
Fruit , Plant Leaves , Flowers , Massachusetts , PlantsABSTRACT
Salivary antimicrobial protein (AMP) expression is a primary determinant of mucosal immunity. This expression can be altered by exercise. While salivary IgA has been extensively studied, less is known about Lysozyme (Lys) and Lactoferrin (Lac). Knowledge on how sex and menstrual phase affect mucosal immunity is also limited. The purpose of this study was to examine how sex, menstrual phase, and exercise impact IgA, Lys, and Lac expression. Men (n = 9) and women (n = 9) ran for 45 min at 75% VO2(peak). Women were tested in the follicular and luteal phase. Saliva was collected pre-exercise, immediately post-exercise and 1 h postexercise. Pre-exercise, women had higher secretion rates of IgA compared to men (154 +/- 106 vs 85 +/- 44 microg/min) (p < 0.05). Lac secretion rate increased with exercise in both sexes and remained above baseline 1 h after exercise in men (7460 +/- 4839 ng/min), but had returned to pre-exercise levels at 1 h post-exercise in women (5720 +/- 4661 ng/min) (time * sex interaction, p < 0.05). Men had higher secretion rates of Lys (p < 0.05) at each time point compared to women (Men pre-exercise: 31042 +/- 23132, post-exercise: 29521 +/- 13205, 1 h post-exercise: 41229 +/- 31270 ng/min vs Women pre-exercise: 11585 +/- 10367, post-exercise: 22719 +/- 19452, 1 h post-exercise: 17303 +/- 11419 ng/min). Both sexes increased the secretion rate of Lys and Lac with exercise, whereas IgA was unchanged. Menstrual phase did not affect IgA, Lys, or Lac and men and women did not differ in saliva flow rates. In conclusion, regularly menstruating women who are not taking hormonal contraceptives differently express AMPs compared to men.
Subject(s)
Amylases/analysis , Exercise/physiology , Immunity, Mucosal , Immunoglobulin A, Secretory/analysis , Lactoferrin/analysis , Menstrual Cycle/immunology , Muramidase/analysis , Running/physiology , Saliva/chemistry , Salivary Proteins and Peptides/analysis , Sex Characteristics , Anthropometry , Estradiol/blood , Exercise Test , Female , Heart Rate , Humans , Male , Oxygen Consumption , Progesterone/blood , Saliva/metabolism , Secretory Rate , Young AdultABSTRACT
BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has increased the rate of nurses leaving practice, which has highlighted the importance of new graduate nurse orientation. The literature has limited recommendations for orientation strategies. METHOD: The goal of this study was to determine what changes have occurred in orientation processes for new graduate nurses since the COVID-19 pandemic. A survey of nurse leaders was used to examine changes and opportunities. RESULTS: Leaders are more intentional with orientation processes, including frequent check-ins and increased discussion of time management, difficult conversations, and workplace violence. Individualized orientation plans are used, along with a stronger focus on nurse wellness. CONCLUSION: Recommendations include continuing support after orientation is completed and partnering with academia to provide content on stress management and wellness. Innovative and cost-effective transition to practice programs are needed to meet the needs of new nurses. [J Contin Educ Nurs. 2024;55(7):345-350.].
Subject(s)
COVID-19 , Inservice Training , SARS-CoV-2 , Humans , COVID-19/nursing , COVID-19/epidemiology , Male , Female , Adult , Middle Aged , Inservice Training/organization & administration , Follow-Up Studies , Pandemics , Nursing Staff, Hospital/education , Surveys and Questionnaires , Education, Nursing, Continuing/organization & administrationABSTRACT
To select residues in coagulation factor XIa (FXIa) potentially important for substrate and inhibitor interactions, we examined the crystal structure of the complex between the catalytic domain of FXIa and the Kunitz protease inhibitor (KPI) domain of a physiologically relevant FXIa inhibitor, protease nexin 2 (PN2). Six FXIa catalytic domain residues (Glu(98), Tyr(143), Ile(151), Arg(3704), Lys(192), and Tyr(5901)) were subjected to mutational analysis to investigate the molecular interactions between FXIa and the small synthetic substrate (S-2366), the macromolecular substrate (factor IX (FIX)) and inhibitor PN2KPI. Analysis of all six Ala mutants demonstrated normal K(m) values for S-2366 hydrolysis, indicating normal substrate binding compared with plasma FXIa; however, all except E98A and K192A had impaired values of k(cat) for S-2366 hydrolysis. All six Ala mutants displayed deficient k(cat) values for FIX hydrolysis, and all were inhibited by PN2KPI with normal values of K(i) except for K192A, and Y5901A, which displayed increased values of K(i). The integrity of the S1 binding site residue, Asp(189), utilizing p-aminobenzamidine, was intact for all FXIa mutants. Thus, whereas all six residues are essential for catalysis of the macromolecular substrate (FIX), only four (Tyr(143), Ile(151), Arg(3704), and Tyr(5901)) are important for S-2366 hydrolysis; Glu(98) and Lys(192) are essential for FIX but not S-2366 hydrolysis; and Lys(192) and Tyr(5901) are required for both inhibitor and macromolecular substrate interactions.
Subject(s)
Amyloid beta-Protein Precursor/physiology , Catalytic Domain , Factor XIa/antagonists & inhibitors , Factor XIa/physiology , Amino Acid Sequence , Amino Acid Substitution , Aprotinin , Catalysis , Humans , Kinetics , Protease Inhibitors , Protein Structure, TertiaryABSTRACT
As a result of the COVID-19 pandemic, newly graduating nurses have entered into rapidly changing clinical environments, experiencing healthcare in a manner for which they were not fully prepared. The purpose of this study is to describe the lived experience of these newly graduated registered nurses (RNs) who transitioned to practice during the COVID-19 pandemic, and to gain understanding of how to better prepare future graduates for similar situations. A multisite qualitative phenomenological design was used in this study of 12 frontline nurses that graduated in the spring of 2020 and transitioned into their new role as RNs. A trained research team conducted semistructured interviews and completed a thematic analysis of the data. The results were six themes that emerged from the study participants' interviews: (1) fear, (2) emotional conflict, (3) self-doubt, (4) alone, (5) communication barriers, and (6) finding the positive.
Subject(s)
COVID-19 , Nurses , Humans , Pandemics , Professional Practice , Qualitative ResearchABSTRACT
Temperate understory plant species are at risk from climate change and anthropogenic threats that include increased deer herbivory, habitat loss, pollinator declines and mismatch, and nutrient pollution. Recent work suggests that spring ephemeral wildflowers may be at additional risk due to phenological mismatch with deciduous canopy trees. The study of this dynamic, commonly referred to as "phenological escape", and its sensitivity to spring temperature is limited to eastern North America. Here, we use herbarium specimens to show that phenological sensitivity to spring temperature is remarkably conserved for understory wildflowers across North America, Europe, and Asia, but that canopy trees in North America are significantly more sensitive to spring temperature compared to in Asia and Europe. We predict that advancing tree phenology will lead to decreasing spring light windows in North America while spring light windows will be maintained or even increase in Asia and Europe in response to projected climate warming.
Subject(s)
Deer , Animals , Temperature , Seasons , Trees , Climate ChangeABSTRACT
Concord, Massachusetts, USA has served as an active location for phenological observations since philosopher and naturalist Henry David Thoreau began recording plant and animal occurrence and phenology in 1851. Since that time, numerous naturalists, scientists, and researchers have continued this tradition, creating an invaluable time series of 758 species in a single location. In total, 13,441 phenological records, spanning 118 years, now exist, with observations of many species ongoing. Relative abundance data for an additional 200 plant species is also provided. Thoreau's published journals and records in Special Collections libraries at the Concord Free Public Library, Harvard University, Peabody Essex Museum, and Morgan Library and Museum provide insight into his methods of routinely walking around Walden Pond, through natural areas, and within the town of Concord, seeking the first leaf or flower on plants, seasonal observations of migratory birds, and fruit maturation times. Several amateur naturalists, and most recently the present research group, have followed this method of regularly searching Concord for the earliest signs of seasonal events, visiting many of the same locations including Walden Pond, the site made famous by Thoreau. While Thoreau's observations were initially made out of a curious desire to document the natural world, these data have led to dozens to contemporary studies, addressing timely issues such as climate change, conservation, ecology, and invasive species. This time series of data, initiated by Thoreau and continued by others, has resulted in dozens of peer-reviewed publications, a popular science book, and numerous educational and outreach opportunities. These data grow increasingly valuable with time and as new and creative studies are undertaken with Thoreau's historic records. No copyright restrictions apply to the use of this data set other than citing this publication.
Subject(s)
Flowers , Plants , Animals , Birds , Climate Change , Humans , Massachusetts , Plant Leaves , SeasonsABSTRACT
Aortoesophageal fistula (AEF) formation nearly always results in catastrophic consequences. As a result of its development being extremely rare, many may never consider it in their differential. Although prognosis is extremely grim, early diagnosis and intervention is considered the optimal means to enhance one's prognosis. We present a case of AEF formation secondary to a Stanford B aortic dissection, along with a review of literature and terminology involved in describing such pathology.
Subject(s)
Aortic Aneurysm, Abdominal/pathology , Aortic Aneurysm, Thoracic/pathology , Aortic Diseases/pathology , Aortic Dissection/complications , Esophageal Fistula/pathology , Fistula/pathology , Aortic Dissection/pathology , Autopsy , Fatal Outcome , Female , Humans , Middle AgedABSTRACT
Atopic dermatitis is a common entity encountered in clinical practice. A subgroup within the atopic dermatitis cohort may develop viral infection on skin lesions appearing as a vesiculopapular pattern. This process is termed eczema herpeticum and may pose a challenge to the clinician as it can appear similar to orthopoxvirus infections, most notably smallpox and monkeypox. Because these conditions are considered as potential bioterrorism threats, confirmatory testing via histological examination, viral culture, immunohistochemical staining or PCR is recommended. Additionally, antiviral therapy should be promptly initiated as eczema herpeticum can disseminate or become superinfected with bacterial species. Early recognition and good communication with pathology can reduce morbidity and confirm the disease process.
Subject(s)
Dermatitis, Atopic/complications , Kaposi Varicelliform Eruption/diagnosis , Adolescent , Antiviral Agents/therapeutic use , Diagnosis, Differential , Humans , Kaposi Varicelliform Eruption/complications , Kaposi Varicelliform Eruption/drug therapy , MaleABSTRACT
Heat poses an urgent threat to public health in cities, as the urban heat island (UHI) effect can amplify exposures, contributing to high heat-related mortality and morbidity. Urban trees have the potential to mitigate heat by providing substantial cooling, as well as co-benefits such as reductions in energy consumption. The City of Boston has attempted to expand its urban canopy, yet maintenance costs and high tree mortality have hindered successful canopy expansion. Here, we present an interactive web application called Right Place, Right Tree-Boston that aims to support informed decision-making for planting new trees. To highlight priority regions for canopy expansion, we developed a Boston-specific Heat Vulnerability Index (HVI) and present this alongside maps of summer daytime land surface temperatures. We also provide information about tree pests and diseases, suitability of species for various conditions, land ownership, maintenance tips, and alternatives to tree planting. This web application is designed to support decision-making at multiple spatial scales, to assist city officials as well as residents who are interested in expanding or maintaining Boston's urban forest.
Subject(s)
Conservation of Energy Resources/methods , Trees/growth & development , Agriculture , Boston , Decision Making , Hot Temperature , Urban RenewalABSTRACT
In 2009, the International Society for Heart and Lung Transplantation recognized the importance and challenges surrounding generic drug immunosuppression. As experience with generics has expanded and comfort has increased, substantial issues have arisen since that time with other aspects of immunomodulation that have not been addressed, such as access to medicines, alternative immunosuppression formulations, additional generics, implications on therapeutic drug monitoring, and implications for special populations such as pediatrics and older adults. The aim of this consensus document is to address critically each of these concerns, expand on the challenges and barriers, and provide therapeutic considerations for practitioners who manage patients who need to undergo or have undergone cardiothoracic transplantation.
Subject(s)
Consensus , Drugs, Generic/pharmacology , Graft Rejection/prevention & control , Immunosuppression Therapy/methods , Immunosuppressive Agents/pharmacology , Lung Transplantation , Drug Substitution , HumansABSTRACT
INTRODUCTION: We conducted a randomized, observer-blind, non-inferiority, parallel-group clinical study of diphtheria, tetanus, pertussis, hepatitis B, and Haemophilus influenzae type b conjugate (pentavalent) vaccination of infants in India. Goals were to determine whether the seropositivity rate after vaccination via disposable-syringe jet injector (DSJI) was non-inferior to that via needle and syringe (N-S), and to compare the safety of vaccination by the two methods. METHODS: Healthy children received a three-dose series of vaccine intramuscularly by DSJI or N-S beginning at 6-8 weeks of age. Immunoglobulin G antibody levels were measured by ELISA at 4-6 weeks after the third dose. The main secondary endpoint was safety, measured as injection site and systemic reactions. DISCUSSION: The study was stopped early out of caution beyond that specified in the protocol stopping criteria, after the Data Safety Committee noted a higher frequency of injection site reactions, especially moderate and severe, in the DSJI group. As a result, 128 subjects-DSJI group 61; N-S group 67-completed the study, rather than the 340 planned, and the study was not sufficiently powered to compare immunogenicity endpoints for the groups. Descriptive statistics indicate that seropositivity induced by vaccination with the DSJI was similar to that of N-S for all five antigens. Pentavalent vaccine includes whole-cell pertussis vaccine and an aluminum adjuvant, which may have contributed to the higher number of local reactions with the DSJI. The reactions caused no serious or long-term sequelae, and may be more acceptable in other populations or circumstances.US National Institutes of Health clinical trials identifier: NCT02409095.
ABSTRACT
POEMS is a rare multisystem paraneoplastic syndrome featuring polyneuropathy, organomegaly, endocrinopathy, a monoclonal protein, and skin changes. In the relatively few reported biopsies of POEMS-associated cutaneous hyperpigmentation, the most common skin finding seen in patients with the disorder, only a non-specific inflammatory infiltrate has been demonstrated histologically. We present the case of a 79-year-old man with polyneuropathy, autoimmune thyroiditis, pancytopenia, and a history of lymphadenopathy who presented to the inpatient dermatology service with cutaneous hyperpigmentation. A skin biopsy of a hyperpigmented area showed a cutaneous lymphoplasmacytic infiltrate, prompting further investigation. A monoclonal IgM-lambda paraprotein was subsequently identified, leading to administration of combination chemotherapy for a diagnosis of POEMS syndrome. The novel finding of a lymphoplasmacytic infiltrate in POEMS-associated hyperpigmentation suggests a diagnostic role for skin biopsy in these patients.
Subject(s)
Hyperpigmentation/pathology , Immunoglobulin M/blood , Immunoglobulin lambda-Chains/blood , POEMS Syndrome/pathology , Paraproteinemias/blood , Paraproteinemias/pathology , Aged , Humans , Lymphocytes/pathology , Male , Plasma Cells/pathologyABSTRACT
Until recently, patients with relapsed Hodgkin's lymphoma after brentuximab vedotin (Bv) treatments had poor treatment outcomes. Checkpoint inhibitors such as nivolumab and pembrolizumab that bind to and inhibit programmed cell death protein-1 (PD-1), have demonstrated an overall response rate of 70% in Hodgkin's lymphoma patients; however, complete response is still low at 20% with median progression-free survival of 14 months. There are ongoing clinical studies to seek out synergistic combinations, with the goal of improving the complete response rates for the cure of Hodgkin's lymphoma. Although radiotherapy has a limited survival benefit in such refractory patients, several preclinical models and anecdotal clinical evidence have suggested that combining local tumor irradiation with checkpoint inhibitors can produce systemic regression of distant tumors, an abscopal effect. Most of these reported studies on the response with local conformal radiotherapy and checkpoint inhibitors in combination with the anti-cytotoxic T-lymphocyte associated antigen-4 (CTLA-4) antibody-ipilimumab are in melanoma. Here we report in our case series that the checkpoint inhibitors that block CTLA4 and B7-homolog 1 (B7-H1) or PD-1 in preclinical radiotherapy models have shown an increased the rate of tumor regression. Our case series demonstrates that combining local irradiation with anti-PD-1 checkpoint blockade treatment is feasible and synergistic in refractory Hodgkin's lymphoma. Correlative studies also suggest that the expression of programmed death-ligand 1 (PD-L1), DNA damage response and mutational tumor burden can be used as potential biomarkers for treatment response.
Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal/administration & dosage , Hodgkin Disease/drug therapy , Hodgkin Disease/radiotherapy , Adult , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/immunology , Biomarkers, Tumor/genetics , Brentuximab Vedotin , CTLA-4 Antigen/antagonists & inhibitors , CTLA-4 Antigen/immunology , Combined Modality Therapy , DNA Damage/drug effects , DNA Damage/radiation effects , Disease-Free Survival , Hodgkin Disease/pathology , Humans , Immunoconjugates/therapeutic use , Male , Nivolumab , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/immunology , Treatment OutcomeABSTRACT
BACKGROUND: We conducted a randomized, non-inferiority, clinical study of MMR vaccine by a disposable-syringe jet injector (DSJI) in toddlers in India in comparison with the conventional administration. METHODS: MMR vaccine was administered subcutaneously by DSJI or needle-syringe (N-S) to toddlers (15-18â¯months) who had received a measles vaccine at 9â¯months. Seropositivity to measles, mumps, and rubella serum IgG antibodies was assessed 35â¯days after vaccination. Non-inferiority was concluded if the upper limit of the 95% CI for the difference in the percent of seropositive between groups was less than 10%. Solicited reactions were collected for 14â¯days after vaccination by using structured diaries. RESULTS: In each study group, 170 subjects received MMR vaccine. On day 35, seropositivity for measles was 97.5% [95% CI (93.8%, 99.3%)] in the DSJI group and 98.7% [95% CI (95.5%, 99.8%)] in the N-S group; for mumps, 98.8% [95% CI (95.6%, 99.8%)] and 98.7% [95% CI (95.5%, 99.8%)]; and for rubella, 98.8% [95% CI (95.6%, 99.8%)] and 100% [95% CI (97.7%, 100.0%)]; none of the differences were significant. The day 35 post-vaccination GMTs in DSJI and N-S groups were measles: 5.48â¯IU/ml [95% CI (3.71, 8.11)] and 5.94â¯IU/ml [95% CI (3.92, 9.01)], mumps: 3.83 ISR [95% CI (3.53, 4.14)] and 3.66 ISR [95% CI (3.39, 3.95)] and rubella: 95.27â¯IU/ml [95% CI (70.39, 128.95)] and 107.06â¯IU/ml [95% CI (79.02, 145.06)]; none of the differences were significant. The DSJI group reported 173 solicited local reactions and the N-S group reported 112; most were mild grade. Of the total of 156 solicited systemic adverse events, most were mild, and incidence between the two groups was similar. CONCLUSIONS: MMR vaccination via DSJI is as immunogenic as vaccination by N-S. Safety profile of DSJI method is similar to N-S except for injection site reactions which are more with DSJI and are well-tolerated. Registration US National Institutes of Health clinical trials identifier - NCT02253407. Clinical trial registry of India identifier - CTRI/2013/05/003702.
Subject(s)
Injections, Jet/instrumentation , Measles-Mumps-Rubella Vaccine/administration & dosage , Measles-Mumps-Rubella Vaccine/immunology , Disposable Equipment , Female , Humans , Immunogenicity, Vaccine , Infant , Injections, Jet/methods , Male , Measles/prevention & control , Measles-Mumps-Rubella Vaccine/adverse effects , Mumps/prevention & control , Rubella/prevention & control , SyringesSubject(s)
Heart Transplantation , Heart-Lung Transplantation , Lung Transplantation , Humans , Graft RejectionABSTRACT
Background This study shows the efficacy of treating complex cases neurobiologically using Self-Regulation Therapy (SRT®) within the context of return to work goals. Case presentation This is a single case study of a 32-year-old white female. This case study follows a client with concurrent diagnoses of post-traumatic stress disorder (PTSD), bipolar disorder I and substance abuse over the course of 2 years of treatment with SRT®. Using SRT® as primary modality and Likert Scale self-report on the Zettl Scale of Dysregulation, psychiatric medication monitoring and pharmaceutical tracking, this study shows session summaries and progress. Results After six sessions the client was cleared by her psychiatrist for return to work. Her medications were reduced and her post-traumatic symptoms abated. She no longer met diagnostic criteria for PTSD or substance abuse after nine sessions. She returned to work successfully and maintained sobriety and continued symptom reduction. Follow up over a 2-year time period showed consistency and continued improvements in both her professional and her personal life. Conclusions Clients with complex traumatic history with concurrent diagnosis are typically difficult to treat in traditional psychotherapy with limited long-term success. This creates challenges in therapy because the traumas occur during key developmental periods of life. This study shows the efficacy of treating complex cases neurobiologically using SRT®. Using SRT®, clinicians are able to address both developmental and complex trauma to reduce sympathetic arousal in the nervous system providing symptom reduction and even resolution of previous clinical diagnoses.
Subject(s)
Bipolar Disorder/therapy , Psychotherapy/methods , Return to Work , Self-Control , Stress Disorders, Post-Traumatic/therapy , Substance-Related Disorders/therapy , Adult , Bipolar Disorder/complications , Female , Humans , Stress Disorders, Post-Traumatic/complications , Substance-Related Disorders/complicationsABSTRACT
OBJECTIVES: To characterize and quantitate hemoglobin (Hb) variants discovered during biometric hemoglobin A1c (HbA1c) analyses in a large multiethnic population with a focus on the effect of variants on testing method and results. METHODS: In total, 13,913 individuals had their HbA1c measured via ion-exchange high-performance liquid chromatography. Samples that had a variant Hb detected or HbF fraction more than 25% underwent variant Hb characterization and confirmation by gel electrophoresis. RBC indices were also evaluated for possible concomitant thalassemia. RESULTS: Of the 13,913 individuals evaluated, 524 (3.77%) had an Hb variant. The prevalence of each variant was as follows: HbS trait (n = 396, 2.85%), HbSS disease (n = 4, 0.03%), HbC trait (n = 85, 0.61%), HbCC disease (n = 2, 0.01%), HbSC disease (n = 5, 0.04%), HbE trait (n = 18, 0.13%), HbD or G trait (n = 9, 0.06%), HbS ß-thalassemia + disease (n = 1, 0.01%), hereditary persistence of HbF (n = 2, 0.01%), and HbMontgomery trait (n = 1, 0.01%). Concomitant α-thalassemia was detected in 20 (3.82%) of the 524 individuals with an Hb variant. CONCLUSIONS: This study represents one of the largest epidemiologic investigations into the prevalence of Hb variants in a North American metropolitan, multiethnic workforce and their dependents and reinforces the importance of method selection in populations with Hb variants.