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1.
Immunology ; 166(2): 238-248, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35290663

RESUMEN

Sialic acid-binding immunoglobulin-type lectins (Siglecs) are a family of immunoglobulin-type lectins that mediate protein-carbohydrate interactions via sialic acids attached to glycoproteins or glycolipids. Most of the CD33-related Siglecs (CD33rSiglecs), a major subfamily of rapidly evolving Siglecs, contain a cytoplasmic signaling domain consisting of the immunoreceptor tyrosine-based inhibitory motif (ITIM) and immunoreceptor tyrosine-based switch motif (ITSM) and mediate suppressive signals for lymphoid and myeloid cells. While most CD33rSiglecs are expressed by innate immune cells, such as monocytes and neutrophils, to date, the expression of Siglecs in human T cells has not been well appreciated. In this study, we found that Siglec-5, a member of the CD33rSiglecs, is expressed by most activated T cells upon antigen receptor stimulation. Functionally, Siglec-5 suppresses T cell activation. In support of these findings, we found that Siglec-5 overexpression abrogates antigen receptor induced activation of NFAT and AP-1. Furthermore, we show that GBS ß-protein, a known bacterial ligand of Siglec-5, reduces the production of cytokines and cytolytic molecules by activated primary T cells in a Siglec-5 dependent manner. Our data also show that some cancer cell lines express a putative Siglec-5 ligand(s), and that the presence of soluble Siglec-5 enhances tumor-cell specific T cell activation, suggesting that some tumor cells inhibit T cell activation via Siglec-5. Together, our data demonstrate that Siglec-5 is a previously unrecognized inhibitory T cell immune checkpoint molecule and suggest that blockade of Siglec-5 could serve as a new strategy to enhance anti-tumor T cell functions.


Asunto(s)
Antígenos CD , Antígenos de Diferenciación Mielomonocítica , Proteínas de Punto de Control Inmunitario , Lectinas , Linfocitos T , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Humanos , Proteínas de Punto de Control Inmunitario/metabolismo , Inmunoglobulinas , Lectinas/metabolismo , Ligandos , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico , Linfocitos T/metabolismo , Tirosina
2.
Mol Biol Evol ; 38(1): 48-57, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-32667997

RESUMEN

Direct comparisons between historical and contemporary populations allow for detecting changes in genetic diversity through time and assessment of the impact of habitat fragmentation. Here, we determined the genetic architecture of both historical and modern lions to document changes in genetic diversity over the last century. We surveyed microsatellite and mitochondrial genome variation from 143 high-quality museum specimens of known provenance, allowing us to directly compare this information with data from several recently published nuclear and mitochondrial studies. Our results provide evidence for male-mediated gene flow and recent isolation of local subpopulations, likely due to habitat fragmentation. Nuclear markers showed a significant decrease in genetic diversity from the historical (HE = 0.833) to the modern (HE = 0.796) populations, whereas mitochondrial genetic diversity was maintained (Hd = 0.98 for both). Although the historical population appears to have been panmictic based on nDNA data, hierarchical structure analysis identified four tiers of genetic structure in modern populations and was able to detect most sampling locations. Mitogenome analyses identified four clusters: Southern, Mixed, Eastern, and Western and were consistent between modern and historically sampled haplotypes. Within the last century, habitat fragmentation caused lion subpopulations to become more geographically isolated as human expansion changed the African landscape. This resulted in an increase in fine-scale nuclear genetic structure and loss of genetic diversity as lion subpopulations became more differentiated, whereas mitochondrial structure and diversity were maintained over time.


Asunto(s)
Distribución Animal , Ecosistema , Variación Genética , Leones/genética , África , Animales , Femenino , Genoma Mitocondrial , Masculino , Filogeografía
3.
Immunology ; 163(3): 293-309, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33524161

RESUMEN

The fetal and neonatal immune systems are uniquely poised to generate tolerance to self, maternal and environmental antigens encountered in the womb and shortly after birth. However, the tolerogenic nature of fetal and neonatal immunity can be detrimental in the context of pathogens, leading to overwhelming bacterial infections or chronic viral infections. A variety of mechanisms contribute to fetal and neonatal tolerance, including a propensity to generate Foxp3+ regulatory T cells (Treg cells). However, the mechanism(s) of fetal Foxp3+ T-cell differentiation, the specific antigen-presenting cells required and factors that inhibit Treg generation after the neonatal period are poorly understood. Here, we demonstrate that a subset of CD14+ monocytes expressing the scavenger molecule, CD36, can generate CD4+ and CD8+ T cells that coexpress Foxp3 and T-bet from both umbilical cord blood. These Foxp3+ T-bet+ T cells potently suppress T-cell proliferation and ameliorate xenogeneic graft-versus-host disease. CD14+  CD36+ monocytes provide known Treg-inducing signals: membrane-bound transforming growth factor-beta and retinoic acid. Unexpectedly, adult peripheral blood monocytes are also capable of inducing Foxp3+ T cells from both cord blood and adult peripheral naïve T cells. The induction of Foxp3+ T cells in umbilical cord blood by monocytes was inhibited by the lymphoid fraction of adult peripheral blood cells. These studies highlight a novel immunoregulatory role of monocytes and suggest that antigen presentation by CD36hi monocytes may contribute to the peripheral development of Foxp3+ T-bet+ T cells with regulatory functions in both neonates and adults.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Enfermedad Injerto contra Huésped/inmunología , Monocitos/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Antígenos CD36/metabolismo , Diferenciación Celular , Células Cultivadas , Sangre Fetal/citología , Feto , Factores de Transcripción Forkhead/metabolismo , Humanos , Tolerancia Inmunológica , Terapia de Inmunosupresión , Activación de Linfocitos , Proteínas de Dominio T Box/genética , Trasplante Heterólogo
4.
Cytokine ; 143: 155519, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33858750

RESUMEN

Type I interferons (IFNs) inhibit angiogenesis, the sprouting of new blood vessels, during tissue development, remodeling, and tumor growth. One of the major targets type I IFNs inhibit are circulating monocytes, which promote vascular development by secreting growth factors, chemokines, and proteases. This study tested the hypothesis that IFN-ß directly inhibits monocyte chemotaxis towards VEGF. We were interested in looking at chemotaxis towards VEGF because VEGF is known to create a pro-angiogenesis environment by acting as a stimulator and chemotactic factor for endothelial cells and monocytes. Here, we demonstrate that IFN-ß, a type I IFN, downregulates neuropilin-1 (NRP-1) expression by human monocytes and inhibits chemotaxis induced by vascular endothelial growth factor (VEGF), a NRP-1 ligand. Together, the data suggest that IFN-ß directly downregulates NRP-1 expression in monocytes, thus inhibiting monocyte chemotaxis toward a VEGF enriched environment.


Asunto(s)
Quimiotaxis , Sangre Fetal/citología , Interferón beta/metabolismo , Monocitos/metabolismo , Neuropilina-1/sangre , Factor A de Crecimiento Endotelial Vascular/farmacología , Quimiotaxis/efectos de los fármacos , Células HEK293 , Humanos , Monocitos/efectos de los fármacos , Neuropilina-1/metabolismo , Células THP-1
5.
J Low Genit Tract Dis ; 18(2): 169-73, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24189309

RESUMEN

OBJECTIVES: To determine whether the 2011 electronic health record (EHR) changes led to improved compliance with cervical cancer screening and management of abnormal results in adolescent (<21 y) patients. MATERIALS AND METHODS: Two EHR prompts were implemented in May 2011. The first is a bright yellow alert that pops up whenever a Pap test is ordered in a patient younger than 21 years, recommending against routine screening. The second was a change in wording of the Pap order form, indicating that if Pap testing is done, human papillomavirus (HPV) testing is not appropriate in this age group. RESULTS: The overall rate of Pap testing decreased after the EHR changes (86/759 [11.3%] before vs 69/1,274 [5.4%] after, p < .0005). The rate of Pap testing without a valid indication such as a 12-month follow-up of previous abnormal results also decreased (66/759 [8.7%] before vs 49/1,274 [3.8%] after, p < .0005). Most Pap tests (77%, both before and after EHR changes) were ordered with reflex HPV testing if atypical squamous cells of undetermined significance. Use of the correct Pap order type (Pap alone, no HPV test) did not improve (16/86 [18.6%] vs 15/69 [22%], p = .0857). CONCLUSIONS: These prompts were associated with lower rates of unindicated Pap testing in adolescents but did not improve providers choosing the correct Pap type.


Asunto(s)
Detección Precoz del Cáncer/estadística & datos numéricos , Registros Electrónicos de Salud , Adhesión a Directriz , Neoplasias del Cuello Uterino/diagnóstico , Adolescente , Femenino , Humanos , Estudios Retrospectivos , Adulto Joven
6.
J Low Genit Tract Dis ; 18(1): 26-30, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23959296

RESUMEN

OBJECTIVE: To determine whether compliance with guidelines for cervical cancer screening, particularly use of the human papillomavirus (HPV) test in adult (aged ≥21 y) women, improves with the implementation of educational prompts in the electronic health record (EHR). MATERIALS AND METHODS: Two EHR-based interventions aimed at reducing unindicated HPV tests were implemented in the EHR in late June 2010. The Pap order form was revised with a descriptor next to the cotest (Pap plus HPV test) option advising that this is not for screening in women younger than 30 years, and a link to the American Society for Colposcopy and Cervical Pathology Web site was made available on the EHR home page. Charts of adult women with HPV results from January to December 2010 were reviewed. Appropriateness of HPV test ordering before (period A: from January to June) and after (period B: from July to December) the interventions were compared using the χ(2) test of association. RESULTS: A total of 3,564 HPV tests were performed on adult women at Loyola University Medical Center in 2010. During period A, 1,709 tests were ordered compared with 1,855 tests ordered during period B (p = .014). The proportion of HPV tests without an appropriate indication decreased significantly after the EHR changes (20% for period A vs 13% for period B, p < .0005). This significant decrease was seen in both primary care (22% in period A vs 12% in period B, p < .0005) and obstetrics and gynecology (Ob/Gyn) (19% vs 13%, p < .0005). CONCLUSIONS: Electronic health record-based tools improve compliance with cervical cancer screening guidelines.


Asunto(s)
Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/estadística & datos numéricos , Registros Electrónicos de Salud , Pruebas de ADN del Papillomavirus Humano/métodos , Pruebas de ADN del Papillomavirus Humano/estadística & datos numéricos , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Adulto , Femenino , Adhesión a Directriz/estadística & datos numéricos , Humanos , Persona de Mediana Edad , Papillomaviridae/genética , Estudios Retrospectivos , Adulto Joven
7.
PLoS One ; 19(8): e0308068, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39141605

RESUMEN

In Africa, humans and large carnivores compete over access to resources, including prey. Disturbance by humans to kills made by carnivores, often for purposes of obtaining all or portions of the carcass, constitutes a form of human-wildlife conflict. However the occurrence of this practice, known as human kleptoparasitism, and its impact on carnivores has received little scientific attention. We obtained expert opinions from African lion researchers and stakeholders via a standardized questionnaire to characterize the geographic extent and frequency of human kleptoparasitism as it occurs in modern times. Our survey found modern human kleptoparasitism on kills made by lions, and possibly other large carnivores in Africa, to be geographically more widespread than previously reported. Meat lost to humans requires carnivores to hunt and kill additional prey thereby causing stress, increasing their energetic costs and risks of natural injury, and exposing them to risk of direct injury or death from human usurpers. Because of their conspicuous behaviors and tendency towards killing large-bodied prey, lions are particularly susceptible to humans detecting their kills. While human kleptoparasitism was geographically widespread, socio-economic factors influenced the frequency of occurrence. Prey type (wild game or domestic livestock) influenced human attitudes towards meat theft; ownership allows for legal recovery of livestock carcasses, while possessing wild game meat is mostly illegal and may incur penalties. Meat theft was associated with other illegal activities (i.e., illegal mining) and most prevalent among people of low income, including underpaid game scouts. Despite quantifiable costs to carnivores of human disturbance to their kills, the majority of experts surveyed reported a lack of knowledge on this practice. We propose that human disturbance at kills, especially loss of prey through human kleptoparasitism, constitutes an important anthropogenic threat that may seriously impact energy budgets of individual lions and other scavengers when meat and carcasses are removed from the ecosystem, and that the costs incurred by carnivores warrants further investigation.


Asunto(s)
Conservación de los Recursos Naturales , Leones , Carne , Conducta Predatoria , Animales , Humanos , Conservación de los Recursos Naturales/economía , África , Caza , Encuestas y Cuestionarios , Animales Salvajes
8.
J Low Genit Tract Dis ; 17(2): 175-81, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23343700

RESUMEN

OBJECTIVE: This study aimed to determine whether electronic medical record (EMR)-based tools influence providers' compliance with guidelines for cervical cancer screening in adolescent (<21 y) patients. MATERIALS AND METHODS: Three EMR-based tools to educate providers on cervical cancer screening guidelines were implemented midyear in 2010. Charts of adolescents with Pap and/or human papillomavirus results from January to December 2010 were reviewed. Physicians' demographic data were collected. Appropriateness of the index Pap and follow-up were determined using American Society for Colposcopy and Cervical Pathology guidelines. RESULTS: A total of 380 Pap tests were completed on 374 adolescents. Fewer Pap tests were done after the EMR interventions (229 vs 151, p < .0005). The proportion of Pap tests ordered by primary care providers was significantly higher than obstetrician-gynecologists (Ob/Gyns) (70% vs 30%, p < .0005). The number of Pap tests done by Ob/Gyns decreased 60% after EMR interventions (from 82 to 33, p < .0005) and that done by primary care physicians decreased 20% (from 147 to 118, p = .08). Indicated Pap tests were more often ordered by Ob/Gyn than by primary care, especially after EMR changes (31.4% vs 7.6%, p < .0005). Reflex human papillomavirus testing (if atypical squamous cells of undetermined significance) was high (74%) and did not improve after the EMR changes (72% vs 76%). The rate of co-testing in adolescents decreased in the primary care department after the EMR changes (13% vs 6%, p = .049). CONCLUSIONS: Electronic medical record prompts improved compliance with cervical cytology guidelines for adolescents, suggesting that EMR may be an important tool to enhance compliance with changing recommendations.


Asunto(s)
Detección Precoz del Cáncer/normas , Registros Electrónicos de Salud/estadística & datos numéricos , Adhesión a Directriz , Pautas de la Práctica en Medicina , Neoplasias del Cuello Uterino/diagnóstico , Adolescente , Femenino , Humanos , Estudios Retrospectivos , Frotis Vaginal/estadística & datos numéricos , Frotis Vaginal/tendencias , Adulto Joven
9.
J Ark Med Soc ; 108(13): 300-3, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22799134

RESUMEN

Putting patients at the center of health care is the basic premise of the Patient Centered Medical Home (PCMH). Our clinic, the Family Medical Center (FMC) is located at the University of Arkansas for Medical Sciences campus and has over 23,000 annual patient visits. In 2008, we decided to apply for the National Committee for Quality Assurance' (NCQA) PCMH recognition and had made several process changes at our clinic to meet the requirements. In 2010, FMC was the first clinic in Arkansas to be recognized by NCQA as a Level 3 PCMH. In this article, we share the actions taken and lessons learned in bringing home the PCMH to our practice.


Asunto(s)
Centros Médicos Académicos/organización & administración , Atención Dirigida al Paciente/organización & administración , Arkansas , Registros Electrónicos de Salud/organización & administración , Accesibilidad a los Servicios de Salud/organización & administración , Humanos , Evaluación de Programas y Proyectos de Salud , Sistema de Registros
10.
PeerJ ; 9: e11313, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33976987

RESUMEN

Determining the incidence and causes of craniodental damage in wild carnivores is often constrained by limited access to specimens with associated ecological data, such as prey type and abundance. We assessed dental condition and cranial injuries in lion, leopard, and spotted hyena in relation to prey and predator populations in Zambia's Luangwa Valley, where large prey are more abundant and lion and leopard more numerous, and the Greater Kafue Ecosystem, where smaller prey species are more prevalent and lion and leopard less common. In Luangwa, lions had significantly higher rates of tooth fracture, and blunt trauma injuries attributable to prey-handling, compared to Kafue lions. In contrast, leopards in both regions had similar rates of tooth wear and breakage. Overall, lions showed a significantly higher tooth fracture rate than leopards on a per tooth basis. Spotted hyenas had the highest rates of tooth wear and fracture among all three carnivores, and greatly exceeded previously recorded rates based on historical samples. Despite larger numbers of lion and leopard in Luangwa, there was no difference in incidence of intraspecific injuries between regions. These results are consistent with a greater abundance of large prey species, especially buffalo, in the diets of Luangwa lions, and previous work showing a reliance on smaller prey species in Kafue throughout the large carnivore guild.

11.
Patient Educ Couns ; 103(8): 1568-1573, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32143986

RESUMEN

OBJECTIVE: Uterine leiomyomata are a frequent indication for women seeking gynecologic care [1]. The objective of our study was to assess whether patient knowledge about leiomyomata, anxiety, or satisfaction with counseling differed in patients who received multimedia counseling versus standard counseling. METHODS: Women with leiomyomata who presented to the gynecology clinic at a single institution were randomized to standard counseling or multimedia counseling using the drawMD OB/GYN iPad™ application. Participants completed a pre-counseling questionnaire, received the designated method of counseling, and completed a post-counseling questionnaire. Outcomes of the study included assessment of patient knowledge, satisfaction, and anxiety. RESULTS: Seventy-two participants were randomized. There was no significant difference in post-counseling anxiety between the groups (p = 0.86). For both groups, anxiety significantly improved after counseling. Both groups were satisfied with the counseling they received, however, there was no difference between groups. Participants in both groups significantly improved their knowledge about fibroids post-counseling. CONCLUSION: Counseling of patients with leiomyomata improves patient satisfaction and knowledge. The addition of a multimedia tool may or may not enhance patient counseling. PRACTICE IMPLICATIONS: This is the first prospective, randomized controlled trial evaluating the impact of a multimedia tool on patient education and counseling for patients with leiomyomata.


Asunto(s)
Consejo , Conocimientos, Actitudes y Práctica en Salud , Leiomioma/psicología , Multimedia , Educación del Paciente como Asunto/métodos , Adulto , Ansiedad , Femenino , Humanos , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Satisfacción del Paciente
12.
PLoS One ; 14(5): e0217179, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31150429

RESUMEN

The Luangwa Valley in eastern Zambia is a transverse offshoot of the Great Rift Valley system. This region appears to have an isolating effect as evidenced by suspected endemic subspecies, such as the Cookson's wildebeest and Thornicroft's giraffe. Recent mitochondrial DNA studies demonstrated that African lions in Zambia consist of two highly diverse eastern and western sub-populations. Herein, we report nuclear and mitochondrial DNA results from 409 lions that support this population substructure across Zambia but proposes only partial isolation of the Luangwa Valley with more movement between the populations than previously thought. Population assignment analysis identifies two populations with little evidence of admixture assigning lions to either the eastern or western sub-populations. A high occurrence of private alleles and clear evidence for a Wahlund effect further justify the presence of a highly structured population. But, while mitochondrial DNA analysis still shows little to no matrilineal gene flow (FST = 0.53) between sub-populations, microsatellite analysis suggests there is gene flow (FST = 0.04) with low but significant isolation-by-distance and an average of 6 migrants per generation. Evidence of isolation-by-distance is also found in factorial correspondence analysis with the Lower Zambezi National Park and eastern corridor clusters overlapping isolated clusters of the Luangwa Valley and western sub-population. From this evidence, the Luangwa Valley appears separated from the western sub-population with some dispersal through the southern regions of the eastern sub-population. Both the eastern and western sub-populations have high heterozygosity (0.68 and 0.69, respectively) and genetic diversity (0.47 and 0.50, respectively) values, indicative of genetically healthy populations.


Asunto(s)
Migración Animal , Monitoreo del Ambiente/métodos , Variación Genética , Genética de Población , Leones/genética , Animales , ADN Mitocondrial/genética , Femenino , Geografía , Masculino
14.
Immunol Lett ; 193: 51-57, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29180044

RESUMEN

It has been generally considered that the perinatal immune system is less inflammatory compared to the adult system and type 2 responses predominate perinatal immune responses against antigens. Indeed, previous studies in mice showed that there are cell-intrinsic differences between neonatal and adult CD4T cells. However, studies on human cord blood and infant blood demonstrated that human perinatal T cells do not produce elevated levels of Th2 cytokines with the exception of IL-13. These data raise the question if human T cells in the perinatal blood fundamentally differ from adult T cells. To decipher differences between human perinatal and adult T cells, we performed a focused comparative analysis on purified naïve CD4T cells from umbilical cord blood (UCB) and adult peripheral blood. Our data demonstrate naïve CD4T cells from UCB differ from adult naïve CD4T cells in surface expression of CD26, dipeptidyl peptidase-4. While only a fraction of effector/memory T cells from adult blood express CD26, practically all T cells from UCB express high levels of CD26. We also determined that Th1/Th2 polarizing conditions induce UCB CD4T cells to produce higher levels of IFN-γ and IL-5 compared to adult CD4T cells, respectively. These data demonstrate intrinsic differences between UCB and adult naive CD4T cells and suggest that human perinatal immune responses involve more complex mechanisms than the previously thought Th2-dominant responses.


Asunto(s)
Dipeptidil Peptidasa 4/metabolismo , Sangre Fetal/inmunología , Células Th2/inmunología , Adulto , Células Cultivadas , Femenino , Humanos , Tolerancia Inmunológica , Inmunofenotipificación , Recién Nacido , Interferón gamma/metabolismo , Interleucina-5/metabolismo , Activación de Linfocitos , Embarazo , Balance Th1 - Th2
15.
PLoS One ; 12(10): e0187003, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29049374

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0153648.].

16.
PLoS One ; 11(4): e0153648, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27089506

RESUMEN

Improved age estimation of African lions Panthera leo is needed to address a number of pressing conservation issues. Here we present a formula for estimating lion age to within six months of known age based on measuring the extent of pulp closure from X-rays, or Ratio Of tooth AReas (ROAR). Derived from measurements taken from lions aged 3-13 years for which exact ages were known, the formula explains 92% of the total variance. The method of calculating the pulp/tooth area ratio, which has been used extensively in forensic science, is novel in the study of lion aging. As a quantifiable measure, ROAR offers improved lion age estimates for population modeling and investigations of age-related mortality, and may assist national and international wildlife authorities in judging compliance with regulatory measures involving age.


Asunto(s)
Determinación de la Edad por los Dientes/métodos , Envejecimiento/fisiología , Diente/diagnóstico por imagen , Animales , Femenino , Leones , Masculino , Dinámica Poblacional , Análisis de Regresión , Difracción de Rayos X
17.
PLoS One ; 10(2): e0117237, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25693191

RESUMEN

Sport hunting has reportedly multiple benefits to economies and local communities; however, few of these benefits have been quantified. As part of their lease agreements with the Zambia Wildlife Authority, sport hunting operators in Zambia are required to provide annually to local communities free of charge i.e., provision a percentage of the meat obtained through sport hunting. We characterized provisioning of game meat to rural communities by the sport hunting industry in Zambia for three game management areas (GMAs) during 2004-2011. Rural communities located within GMAs where sport hunting occurred received on average > 6,000 kgs per GMA of fresh game meat annually from hunting operators. To assess hunting industry compliance, we also compared the amount of meat expected as per the lease agreements versus observed amounts of meat provisioned from three GMAs during 2007-2009. In seven of eight annual comparisons of these GMAs, provisioning of meat exceeded what was required in the lease agreements. Provisioning occurred throughout the hunting season and peaked during the end of the dry season (September-October) coincident with when rural Zambians are most likely to encounter food shortages. We extrapolated our results across all GMAs and estimated 129,771 kgs of fresh game meat provisioned annually by the sport hunting industry to rural communities in Zambia at an approximate value for the meat alone of >US$600,000 exclusive of distribution costs. During the hunting moratorium (2013-2014), this supply of meat has halted, likely adversely affecting rural communities previously reliant on this food source. Proposed alternatives to sport hunting should consider protein provisioning in addition to other benefits (e.g., employment, community pledges, anti-poaching funds) that rural Zambian communities receive from the sport hunting industry.


Asunto(s)
Animales Salvajes , Carne , Recreación , Población Rural , Animales , Conservación de los Recursos Naturales/legislación & jurisprudencia , Abastecimiento de Alimentos , Zambia
18.
PLoS One ; 10(12): e0143827, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26674533

RESUMEN

Analysis of DNA sequence diversity at the 12S to 16S mitochondrial genes of 165 African lions (Panthera leo) from five main areas in Zambia has uncovered haplotypes which link Southern Africa with East Africa. Phylogenetic analysis suggests Zambia may serve as a bridge connecting the lion populations in southern Africa to eastern Africa, supporting earlier hypotheses that eastern-southern Africa may represent the evolutionary cradle for the species. Overall gene diversity throughout the Zambian lion population was 0.7319 +/- 0.0174 with eight haplotypes found; three haplotypes previously described and the remaining five novel. The addition of these five novel haplotypes, so far only found within Zambia, nearly doubles the number of haplotypes previously reported for any given geographic location of wild lions. However, based on an AMOVA analysis of these haplotypes, there is little to no matrilineal gene flow (Fst = 0.47) when the eastern and western regions of Zambia are considered as two regional sub-populations. Crossover haplotypes (H9, H11, and Z1) appear in both populations as rare in one but common in the other. This pattern is a possible result of the lion mating system in which predominately males disperse, as all individuals with crossover haplotypes were male. The determination and characterization of lion sub-populations, such as done in this study for Zambia, represent a higher-resolution of knowledge regarding both the genetic health and connectivity of lion populations, which can serve to inform conservation and management of this iconic species.


Asunto(s)
ADN Mitocondrial , Variación Genética , Haplotipos , Leones/genética , Alelos , Animales , Femenino , Frecuencia de los Genes , Geografía , Leones/clasificación , Masculino , Filogenia , Filogeografía , Polimorfismo de Nucleótido Simple , Zambia
19.
PLoS One ; 10(10): e0137975, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26466139

RESUMEN

The evolutionary history of a species is key for understanding the taxonomy and for the design of effective management strategies for species conservation. The knowledge about the phylogenetic position of the lion (Panthera leo) in West/Central Africa is largely based on mitochondrial markers. Previous studies using mtDNA only have shown this region to hold a distinct evolutionary lineage. In addition, anthropogenic factors have led to a strong decline in West/Central African lion numbers, thus, the conservation value of these populations is particularly high. Here, we investigate whether autosomal markers are concordant with previously described phylogeographic patterns, and confirm the unique position of the West/Central African lion. Analysis of 20 microsatellites and 1,454 bp of the mitochondrial DNA in 16 lion populations representing the entire geographic range of the species found congruence in both types of markers, identifying four clusters: 1) West/Central Africa, 2) East Africa, 3) Southern Africa and 4) India. This is not in line with the current taxonomy, as defined by the IUCN, which only recognizes an African and an Asiatic subspecies. There are no indications that genetic diversity in West/Central Africa lions is lower than in either East or Southern Africa, however, given this genetic distinction and the recent declines of lion numbers in this region, we strongly recommend prioritization of conservation projects in West/Central Africa. As the current taxonomic nomenclature does not reflect the evolutionary history of the lion, we suggest that a taxonomic revision of the lion is warranted.


Asunto(s)
ADN Mitocondrial/genética , Marcadores Genéticos/genética , Leones/genética , África Central , África Occidental , Animales , Evolución Biológica , Análisis por Conglomerados , Conservación de los Recursos Naturales , Evolución Molecular , Variación Genética , Geografía , Repeticiones de Microsatélite/genética , Filogenia , Filogeografía , Análisis de Componente Principal , Especificidad de la Especie
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