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1.
Sci Rep ; 14(1): 16221, 2024 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-39003385

RESUMEN

In East Africa, community-based conservation models (CBCMs) have been established to support the conservation of wildlife in fragmented landscapes like the Tarangire Ecosystem, Tanzania. To assess how different management approaches maintained large herbivore populations, we conducted line distance surveys and estimated seasonal densities of elephant, giraffe, zebra, and wildebeest in six management units, including three CBCMs, two national parks (positive controls), and one area with little conservation interventions (negative control). Using a Monte-Carlo approach to propagate uncertainties from the density estimates and trend analysis, we analyzed the resulting time series (2011-2019). Densities of the target species were consistently low in the site with little conservation interventions. In contrast, densities of zebra and wildebeest in CBCMs were similar to national parks, providing evidence that CBCMs contributed to the stabilization of these migratory populations in the central part of the ecosystem. CBCMs also supported giraffe and elephant densities similar to those found in national parks. In contrast, the functional connectivity of Lake Manyara National Park has not been augmented by CBCMs. Our analysis suggests that CBCMs can effectively conserve large herbivores, and that maintaining connectivity through CBCMs should be prioritized.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Herbivoria , Animales , Conservación de los Recursos Naturales/métodos , Tanzanía , Elefantes/fisiología , Dinámica Poblacional , Densidad de Población , Jirafas/fisiología , Equidae/fisiología
2.
Trends Ecol Evol ; 38(7): 666-680, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36935248

RESUMEN

Community-based conservation can support livelihoods and biodiversity, while reinforcing local and Indigenous values, cultures, and institutions. Its delivery can help address cross-cutting global challenges, such as climate change, conservation, poverty, and food security. Therefore, understanding trends in community-based conservation is pertinent to setting and implementing global goals. We undertook a horizon scan to prioritize 15 emerging threats and opportunities expected to impact the future effectiveness of community-based conservation. Topics relate to global biodiversity policy; human rights; shifting human geography; inclusion, diversity, equity, and access; conservation finance and income; and economic reforms. Our findings offer guidance on strengthening community-based conservation to achieve global environmental and development goals.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Humanos , Cambio Climático , Predicción , Geografía
4.
J Am Acad Orthop Surg ; 30(13): e894-e898, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35383608

RESUMEN

Bone marrow stromal cells are regulated by the chemical and physical features of a biomaterial surface. When grown on titanium (Ti) and Ti alloy surfaces, such as titanium-aluminum-vanadium, with specific topographies that mimic the microscale, mesoscale, and nanoscale features of an osteoclast resorption pit, they undergo a rapid change in cell shape to assume a columnar morphology typical of a secretory osteoblast. These cells exhibit markers associated with an osteoblast phenotype, including osteocalcin and osteopontin, and they secrete factors associated with osteogenesis, including bone morphogenetic protein 2, vascular endothelial growth factor, and neurotrophic semaphorins. The pathway involves a shift in integrin expression from α5ß1 to α2ß1 and signaling by Wnt5a rather than Wnt3a. Conditioned media from these cultures can stimulate vasculogenesis by human endothelial cells and osteoblastic differentiation of marrow stromal cells not grown on the biomimetic substrate, suggesting that the surface could promote osteogenesis in vivo through similar mechanisms. In vivo studies using a variety of animal models confirm that implants with biomimetic surfaces result in improved osseointegration compared with Ti implants with smooth surfaces, as do meta-analyses comparing clinical performance of implant surface topographies.


Asunto(s)
Oseointegración , Osteogénesis , Animales , Diferenciación Celular/fisiología , Células Endoteliales , Humanos , Oseointegración/fisiología , Osteogénesis/fisiología , Propiedades de Superficie , Titanio , Factor A de Crecimiento Endotelial Vascular
6.
J Dr Nurs Pract ; 12(2): 148-158, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32745028

RESUMEN

BACKGROUND: Osteoarthritis (OA) is a serious public health problem that affects millions in the United States (Hootman & Helmick, 2006). National health objectives indicate an urgent need to increase the number of people educated about the causes, prevention, and treatment of OA (Sleath, Cahoon, Sloane, & Callahan, 2008). The most effective OA reduction strategies include health education, health promotion, and self-management education (Schulz, et al., 2015). Studies examining the design and implementation of education are limited. Researchers have established the a link between improving knowledge and improved health outcomes; reduced pain, increased mobility, improved joint health, and delayed surgery (Szychlinska, Leonardi, Al-Qahtani, M., Mobasheri, & Musumeci, 2016). Beneficial interventions may decrease the disability associated with OA and the need for more invasive treatments (Sharma, 2016). In our previous article titled Components of an Effective Osteoarthritis Self-Management Program, provided components needed for program implementation and how to measure the program's success by using the nursing Health Belief Model. OBJECTIVE: The purpose of this program evaluation is to improve program information and increase patient knowledge. METHOD: This evaluation used two mixed methods: (a) standardized survey (Figure 1), (b) instructor interview (Figure 2). Both evaluations were conducted by the authors with defined methods and conditions discussed under sections Participant Survey Method and Instructor Interview Method. RESULTS: The program evaluation goal was met with positive reviews from all 67 participants who attended the program. Instructor interviews uncovered reasons for volunteering and gathered data used for future recommendations. CONCLUSION: This program evaluation will provide tools for program implementation and evaluation by health organizations with the long-term aim of reducing the burden of OA and healthcare costs.

7.
Open Orthop J ; 12: 105-114, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29619124

RESUMEN

BACKGROUND: Over the past decade, phenotypes have been used to help categorize knee osteoarthritis patients relative to being subject to disease, disease progression, and treatment response. A review of potential phenotype selection is now appropriate. The appeal of using phenotypes is that they most rely on simple physical examination, clinically routine imaging, and demographics. The purpose of this review is to describe the panoply of phenotypes that can be potentially used in osteoarthritis research. METHODS: A search of PubMed was used singularly to review the literature on knee osteoarthritis phenotypes. RESULTS: Four phenotype assembly groups were based on physical features and noninvasive imaging. Demographics included metabolic syndrome (dyslipidemia, hypertension, obesity, and diabetes). Mechanical characteristics included joint morphology, alignment, the effect of injury, and past and present history. Associated musculoskeletal disorder characteristics included multiple joint involvement, spine disorders, neuromuscular diseases, and osteoporosis. With the knee as an organ, tissue characteristics were used to focus on synovium, meniscus, articular cartilage, patella fat pad, bone sclerosis, bone cysts, and location of pain. DISCUSSION: Many of these phenotype clusters require further validation studies. There is special emphasis on knee osteoarthritis phenotypes due to its predominance in osteoarthritic disorders and the variety of tissues in that joint. More research will be required to determine the most productive phenotypes for future studies. CONCLUSION: The selection and assignment of phenotypes will take on an increasing role in osteoarthritis research in the future.

8.
J Eval Clin Pract ; 24(3): 600-606, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29380477

RESUMEN

RATIONALE, AIMS, AND OBJECTIVES: As the Sustainable Development Goals are rolled out worldwide, development leaders will be looking to the experiences of the past to improve implementation in the future. Systems thinking and complexity science (ST/CS) propose that health and the health system are composed of dynamic actors constantly evolving in response to each other and their context. While offering practical guidance for steering the next development agenda, there is no consensus as to how these important ideas are discussed in relation to health. This systematic review sought to identify and describe some of the key terms, concepts, and methods in recent ST/CS literature. METHOD: Using the search terms "systems thinkin * AND health OR complexity theor* AND health OR complex adaptive system* AND health," we identified 516 relevant full texts out of 3982 titles across the search period (2002-2015). RESULTS: The peak number of articles were published in 2014 (83) with journals specifically focused on medicine/healthcare (265) and particularly the Journal of Evaluation in Clinical Practice (37) representing the largest number by volume. Dynamic/dynamical systems (n = 332), emergence (n = 294), complex adaptive system(s) (n = 270), and interdependent/interconnected (n = 263) were the most common terms with systems dynamic modelling (58) and agent-based modelling (43) as the most common methods. CONCLUSIONS: The review offered several important conclusions. First, while there was no core ST/CS "canon," certain terms appeared frequently across the reviewed texts. Second, even as these ideas are gaining traction in academic and practitioner communities, most are concentrated in a few journals. Finally, articles on ST/CS remain largely theoretical illustrating the need for further study and practical application. Given the challenge posed by the next phase of development, gaining a better understanding of ST/CS ideas and their use may lead to improvements in the implementation and practice of the Sustainable Development Goals.


Asunto(s)
Atención a la Salud , Análisis de Sistemas
9.
Acad Radiol ; 24(2): 175-183, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28010915

RESUMEN

RATIONALE AND OBJECTIVES: Subchondral insufficiency fractures (SIF), previously termed spontaneous osteonecrosis of the knee, are marked by a sudden onset of severe pain. Other than the size of the lesion, prediction for progression to joint replacement is difficult. The objective was to determine if quantitative analysis of bone texture using digital tomosynthesis imaging would be useful in predicting more rapid progression to joint replacement. MATERIALS AND METHODS: Tomosynthesis studies of 30 knees with documented SIF were quantified by fractal, mean intercept length (MIL), and line fraction deviation analyses. Fractal dimension, lacunarity, MIL, and line fraction deviation variables measured from these analyses were then correlated to short interval progression to joint replacement surgery. RESULTS: Higher odds for joint replacement were related to higher values of the standard deviation of slope lacunarity and to morphometric measures (eg, MIL). CONCLUSIONS: Using digital tomosynthesis images for bone texture assessment may help distinguish condylar bone response in SIF, potentially acting as a clinically relevant predictive tool. In the future, contrasting SIF to the more gradual long-term process of osteoarthritis, there may be a better understanding of the different mechanisms for the two conditions.


Asunto(s)
Fracturas por Estrés/diagnóstico , Traumatismos de la Rodilla/diagnóstico , Osteonecrosis/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Fractales , Humanos , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad
10.
Am J Orthop (Belle Mead NJ) ; 44(6): E184-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26047003

RESUMEN

Reports in the literature have suggested a causal relationship between knee arthroscopy and spontaneous osteonecrosis of the knee (SONK). We conducted a study to determine if there are imaging characteristics associated with SONK and if there is a relationship between arthroscopy and SONK. In this retrospective review, we compared preoperative and postoperative findings in 11 patients (12 joints) who developed SONK after arthroscopy with findings in 11 age- and sex-matched controls who did not develop SONK after arthroscopy. There were no significant preoperative radiologic differences between the SONK and control groups. All 12 SONK lesions seen on magnetic resonance imaging were in the medial femoral condyle. Six SONK knees developed the lesion after arthroscopy, and 6 had SONK lesions before arthroscopy. Eleven of the 12 SONK knees had a medial meniscal tear, compared with 8 medial meniscal tears and 3 lateral meniscal tears in the control group. Eight SONK knees and 5 control patients had medial meniscal extrusion of more than 3 mm. A causal relationship between knee arthroscopy and SONK is questionable.


Asunto(s)
Artroscopía/efectos adversos , Fémur/patología , Articulación de la Rodilla/patología , Osteonecrosis/etiología , Adulto , Anciano , Femenino , Humanos , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteonecrosis/patología , Estudios Retrospectivos
11.
Pain Manag ; 4(6): 427-36, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25494694

RESUMEN

Knee osteoarthritis (KOA) is the most common degenerative arthritis and is treated by a wide range of practitioners. Treatment planning requires knowledge of the knee joint components and the influence of systemic and environmental factors. The treatment of KOA has changed little in 50 years. We are entering a new stage where KOA is now being viewed as an organ in failure. Neurotransmission of pain is both peripheral and central. Medical treatment can influence both pathways. Current guidelines for treatment have more rigid criteria based on the literature. In the future, the use of genetic-based biomarkers, clinical patterns of response and imaging characteristics will likely create subgroups of individuals who could benefit from improved designer therapies.


Asunto(s)
Osteoartritis de la Rodilla/etiología , Manejo del Dolor , Dolor/etiología , Humanos , Mediadores de Inflamación/metabolismo , Osteoartritis de la Rodilla/metabolismo , Dolor/metabolismo
12.
Arch Osteoporos ; 9: 194, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25234658

RESUMEN

UNLABELLED: The term insufficiency fracture implies inadequate bone and is applied to some subchondral knee magnetic resonance images. We reviewed bone mineral density, body mass index, meniscal extrusion, comorbidities, and demographics in 32 knee insufficiency fracture patients. Only five were osteoporotic. Meniscal extrusion was predominant. PURPOSE: The literature supports systemic osteoporosis as a risk fracture for spontaneous osteonecrosis of the knee (SONK). SONK is also called a subchondral insufficiency fracture. Recognizing that insufficiency fracture and SONK are related, we designed this retrospective study to determine if knee subchondral insufficiency fractures were associated with osteoporosis based on bone mineral density. METHODS: Based on magnetic resonance imaging findings, 32 patients were diagnosed as having an insufficiency fracture by an orthopaedic surgeon with magnetic resonance imaging confirmation by a musculoskeletal radiologist. We reviewed body mass index, age, sex, comorbidities, demographics, and bone mineral density using both T-scores and Z-scores. RESULTS: The average age was 70, and only five patients were osteoporotic. Twenty-six of the 32 patients were female. The average age-related Z-score was 1 standard deviation above normal. CONCLUSIONS: We conclude that osteoporosis is not the underlying cause of this disorder in the majority of patients.


Asunto(s)
Fracturas por Estrés/etiología , Traumatismos de la Rodilla/etiología , Osteonecrosis/etiología , Osteoporosis/complicaciones , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Densidad Ósea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Lesiones de Menisco Tibial
13.
Mil Med ; 179(8): 815-20, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25102523

RESUMEN

Military personnel have a greater risk of developing osteoarthritis (OA) than the general population. OA is a chronic, painful, and debilitating disease with a high cost burden. Compared with the general population, a higher prevalence of post-traumatic OA has been reported in the military. Using recent literature, we aim to improve the understanding of post-traumatic OA, with an exploration of the pathophysiology of OA. Our review encompasses the current treatment modalities for alleviating the pain from OA with a focus on viscosupplementation. A multimodal approach may be beneficial for the relief of OA pain and improvement of function in military personnel with early OA, and may lower the cost burden.


Asunto(s)
Artralgia/tratamiento farmacológico , Personal Militar , Osteoartritis/tratamiento farmacológico , Viscosuplementación , Viscosuplementos/uso terapéutico , Artralgia/etiología , Humanos , Osteoartritis/etiología , Estados Unidos
15.
J Arthroplasty ; 29(6): 1243-7, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24360489

RESUMEN

In the early phases, subchondral insufficiency fractures and rapidly destructive osteoarthritis of the hip are often mistaken for osteonecrosis of the hip. Three hip measures were used comparing combined subchondral insufficiency fractures and rapidly destructive 18 osteoarthritis patients to 18 osteonecrosis patients. Due to the rarity of these conditions there was no statistical power. Initial diagnoses for the osteoarthritis patients were recorded. The osteoarthritis group had significantly higher means for Tönnis angle (P < 0.001), lateral center edge angle (P = 0.006), and acetabular extrusion index (P = 0.014). Only 7 of the 18 patients were initially diagnosed without reservation as subchondral insufficiency fracture or rapidly destructive osteoarthritis. Using hip measures will reduce the misdiagnosis of rapid onset osteoarthritis of the hip for osteonecrosis.


Asunto(s)
Errores Diagnósticos/prevención & control , Articulación de la Cadera/diagnóstico por imagen , Osteoartritis de la Cadera/diagnóstico por imagen , Osteonecrosis/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Pesos y Medidas Corporales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/diagnóstico , Osteonecrosis/diagnóstico , Radiografía , Adulto Joven
16.
Rheumatol Int ; 33(8): 2169-73, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22451021

RESUMEN

This study examined whether a non-thermal, non-invasive, pulsed electromagnetic field (PEMF), known to modulate the calmodulin (CaM)-dependent nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway, could reduce pain in early knee OA. This randomized, placebo-controlled, double-blind pilot clinical study enrolled 34 patients. Patient selection required initial VAS ≥4, 2 h of standing activity per day, and no recent interventions such as cortisone injections or surgery. Results showed VAS pain score decreased in the active cohort by 50 ± 11% versus baseline starting at day 1 and persisting to day 42 (P < 0.001). There was no significant decrease in VAS versus baseline at any time point in the sham cohort (P = 0.227). The overall decrease in mean VAS score for the active cohort was nearly threefold that of the sham cohort (P < 0.001). The results suggest that non-thermal, non-invasive PEMF therapy can have a significant and rapid impact on pain from early knee OA and that larger clinical trials are warranted.


Asunto(s)
Campos Electromagnéticos , Magnetoterapia/métodos , Osteoartritis de la Rodilla/terapia , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Proyectos Piloto , Resultado del Tratamiento
19.
J Long Term Eff Med Implants ; 22(3): 237-342, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23582115

RESUMEN

BACKGROUND AND PURPOSE: Developing successful musculoskeletal scaffolds for specific tissue replacement has many challenges. Ideal scaffolds support the physiologic needs of the ingrowth tissue until new cells establish a matrix approximating the biomechanical properties of the original tissue or organ construct. Short- and long-term effects on matrix formation and surrounding tissue are critical for clinical applications. METHOD: This is a review of scaffold development of alginate, fibrin, and poly glycolic and polylactic acid scaffolds by three laboratories. RESULTS: Varied chain structures of alginate modified with an RGD-containing peptide sequence (G4RGDY) promotes cell multiplication. Given the proper mix of chain size and radiation used to reduce chain size, the adjusted rate of degradation showed no long-term effect at 21 weeks in vitro. To date, there are no long-term fibrin-based scaffold constructs. Plasmid DNA-laden 75:25 PLGA microspheres were able to have the microsphere incorporated into the polymer solution, resulting in sustained plasmid DNA release for more than 70 days without significant surrounding tissue effects. CONCLUSION: Years of research on the same construct are required before long-term effects of tissue engineering scaffolds can be determined.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Fibrina/química , Ácido Láctico/química , Ácido Poliglicólico/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Humanos , Ensayo de Materiales , Sistema Musculoesquelético , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
20.
J Long Term Eff Med Implants ; 22(3): 245-51, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23582117

RESUMEN

BACKGROUND: Body mass index (BMI) uses height and weight to determine relative fat content. BMI is used in numerous epidemiologic and mechanical studies of hip and knee osteoarthritis (OA). There are more precise, but cumbersome and expensive, measurements of the contribution of body fat to BMI. Our hypotheses were that there would be a large variation in relative mid-thigh bone, muscle, and fat width within specific BMI range and that relative widths change with age and sex. METHODS: The hospital IRB approved a retrospective review of 340 patients who had a recent knee radiograph for knee OA. Using 5.08-cm (2-inch) increments, six groups were created. At height-adjusted reference points on the lower mid-thigh total thigh diameter (TD), muscle diameter (MD), bone diameter (BD), and nonfat diameter (NFD) were measured. Relative widths within BMI groups (<25, 25-30, 30-40, >40) were compared to age and sex. RESULTS: MD, BD, and NFD ratios showed a wide variation in all BMI groups. As would be expected MD, BD, and NFD ratios decreased with increasing BMI. These ratios did not significantly change with age. However, the MD ratio remains similar for each BMI in men, in women it decreases with BMI. CONCLUSION: Adding relative thigh measurements to BMI data could enhance mechanical and epidemiologic studies.


Asunto(s)
Adiposidad , Índice de Masa Corporal , Tamaño Corporal , Muslo/diagnóstico por imagen , Factores de Edad , Composición Corporal , Huesos/diagnóstico por imagen , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Músculos/diagnóstico por imagen , Radiografía , Estudios Retrospectivos , Factores Sexuales
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