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1.
Proc Natl Acad Sci U S A ; 120(23): e2221840120, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37252998

RESUMEN

Afforestation and reforestation (AR) on marginal land are nature-based solutions to climate change. There is a gap in understanding the climate mitigation potential of protection and commercial AR with different combinations of forest plantation management and wood utilization pathways. Here, we fill the gap using a dynamic, multiscale life cycle assessment to estimate one-century greenhouse gas (GHG) mitigation delivered by (both traditional and innovative) commercial and protection AR with different planting density and thinning regimes on marginal land in the southeastern United States. We found that innovative commercial AR generally mitigates more GHGs across 100 y (3.73 to 4.15 Giga tonnes of CO2 equivalent (Gt CO2e)) through cross-laminated timber (CLT) and biochar than protection AR (3.35 to 3.69 Gt CO2e) and commercial AR with traditional lumber production (3.17 to 3.51 Gt CO2e), especially in moderately cooler and dryer regions in this study with higher forest carbon yield, soil clay content, and CLT substitution. In a shorter timeframe (≤50 y), protection AR is likely to deliver higher GHG mitigation. On average, for the same wood product, low-density plantations without thinning and high-density plantations with thinning mitigate more life cycle GHGs and result in higher carbon stock than that of low-density with thinning plantations. Commercial AR increases the carbon stock of standing plantations, wood products, and biochar, but the increases have uneven spatial distributions. Georgia (0.38 Gt C), Alabama (0.28 Gt C), and North Carolina (0.13 Gt C) have the largest carbon stock increases that can be prioritized for innovative commercial AR projects on marginal land.


Asunto(s)
Gases de Efecto Invernadero , Madera , Madera/metabolismo , Agricultura Forestal , Suelo , Carbono/metabolismo , Georgia
2.
J Drugs Dermatol ; 23(1): 1325-1331, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38206149

RESUMEN

BACKGROUND: A phase 4, prospective, open-label, multicenter study showed that treatment with deoxycholic acid injections (ATX-10) followed by a hyaluronic acid filler (VYC-20L) is safe and effective for reducing submental fullness and improving jawline definition. OBJECTIVE: To quantify changes in the jawline and submental area using 3-dimensional (3D) photogrammetry and conduct an immunohistochemical analysis of submental tissue.  Methods: Participants received 1 to 6 ATX-101 treatments (8 weeks apart) followed by VYC-20L (optional touch-up after 14 days). Changes from baseline in jawline and submental volumes, submental major and minor strain events, submental skin displacement, and submental angles were quantified using photogrammetry. Submental skin biopsies (N=13) were excised for histologic analysis. Treatment-emergent adverse events (TEAEs) were monitored. RESULTS: Fifty-three participants were treated. From baseline to the final study visit, the mean volume increased for the jawline and decreased for the submental area. There was a larger percentage change from baseline in the minor versus major strain event, indicating greater skin surface compression than expansion within the submental area. Mean change from baseline in submental skin position indicated superior and posterior movement from a lateral perspective, while the mean submental angle decreased between baseline and exit. Collagen I and III expression significantly increased from baseline (P<0.05). All participants reported at least 1 TEAE; the majority were mild or moderate in severity. CONCLUSIONS: Dual-modality treatment with ATX-101 and VYC-20L reduces submental fat and improves jawline definition with quantifiable changes in jawline volume, submental volume, strain, skin displacement, and angle, as well as collagen expression. J Drugs Dermatol. 2024;23(1):1325-1331.        doi:10.36849/JDD.7458.


Asunto(s)
Colágeno , Mandíbula , Humanos , Estudios Prospectivos , Biopsia , Ácido Desoxicólico
3.
Phytother Res ; 38(3): 1522-1554, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38281731

RESUMEN

COVID-19, which was first identified in 2019 in Wuhan, China, is a respiratory illness caused by a virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although some patients infected with COVID-19 can remain asymptomatic, most experience a range of symptoms that can be mild to severe. Common symptoms include fever, cough, shortness of breath, fatigue, loss of taste or smell and muscle aches. In severe cases, complications can arise including pneumonia, acute respiratory distress syndrome, organ failure and even death, particularly in older adults or individuals with underlying health conditions. Treatments for COVID-19 include remdesivir, which has been authorised for emergency use in some countries, and dexamethasone, a corticosteroid used to reduce inflammation in severe cases. Biological drugs including monoclonal antibodies, such as casirivimab and imdevimab, have also been authorised for emergency use in certain situations. While these treatments have improved the outcome for many patients, there is still an urgent need for new treatments. Medicinal plants have long served as a valuable source of new drug leads and may serve as a valuable resource in the development of COVID-19 treatments due to their broad-spectrum antiviral activity. To date, various medicinal plant extracts have been studied for their cellular and molecular interactions, with some demonstrating anti-SARS-CoV-2 activity in vitro. This review explores the evaluation and potential therapeutic applications of these plants against SARS-CoV-2. This review summarises the latest evidence on the activity of different plant extracts and their isolated bioactive compounds against SARS-CoV-2, with a focus on the application of plant-derived compounds in animal models and in human studies.


Asunto(s)
COVID-19 , Plantas Medicinales , Animales , Humanos , Anciano , SARS-CoV-2 , Inflamación , Fitoquímicos
4.
Biomacromolecules ; 23(7): 3031-3040, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35748772

RESUMEN

Biomaterials capable of precisely controlling the delivery of agrochemicals/biologics/drugs/fragrances have significant markets in the agriscience/healthcare industries. Here, we report the development of degradable electroactive polymers and their application for the controlled delivery of a clinically relevant drug (the anti-inflammatory dexamethasone phosphate, DMP). Electroactive copolymers composed of blocks of polycaprolactone (PCL) and naturally occurring electroactive pyrrole oligomers (e.g., bilirubin, biliverdin, and hemin) were prepared and solution-processed to produce films (optionally doped with DMP). A combination of in silico/in vitro/in vivo studies demonstrated the cytocompatibility of the polymers. The release of DMP in response to the application of an electrical stimulus was observed to be enhanced by ca. 10-30% relative to the passive release from nonstimulated samples in vitro. Such stimuli-responsive biomaterials have the potential for integration devices capable of delivering a variety of molecules for technical/medical applications.


Asunto(s)
Materiales Biocompatibles , Polímeros , Electricidad , Pirroles
5.
Ecol Appl ; 30(5): e02093, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32065685

RESUMEN

The Amazon harbors one of the most diverse tree floras on earth, and most species depend on mutualists for pollination and seed dispersal. This makes them susceptible to reproductive decline in fragmented forest because many of these mutualists suffer area-related extinction in fragments. It remains unknown, however, whether this highly biodiverse tree flora will reproduce and ultimately persist in fragmented forest. We conducted a 2-yr study of seed fall in an experimentally fragmented, highly diverse Central Amazonian forest. We determined the effect of fragment size (1, 10, 100 ha and continuous forest control) on the density, species richness, functional diversity and functional composition of seeds separated into two data sets: dispersed tree seeds, and undispersed tree seeds. Our results show a 3× reduction in the density of undispersed, non-pioneer tree seeds in fragments of all sizes, indicating reduced seed production of the non-pioneer tree community. The density of dispersed tree seeds was reduced by 6× in fragments of all sizes, while species richness was reduced by 6× in 1-ha fragments and by 3× in 10- and 100-ha fragments compared to intact forest. This provides evidence of reduced community-wide seed dispersal, which became more pronounced with declining fragment size. The functional diversity (FRic) of dispersed tree seeds was reduced 9.6× in small fragments, and significant shifts in the functional composition for 8 of the 10 reproductive and ecological traits studied were identified, suggesting compromised ecosystem functioning. These functional compositional shifts provide evidence for disrupted mutualistic processes in fragments, which include loss of pollination by bees, especially small eusocial (meliponid) bees, and loss of dispersal by primates and large birds, which reduced the frequency of large-seeded tree species. Fragments also lost rare and mature-forest species, and collectively these changes suggest that future tree communities in fragmented Amazonian landscapes will retain a taxonomically and functionally impoverished species pool with a biased functional composition unless efforts are undertaken to conserve dispersal by large frugivores and pollination by meliponid bees.


Asunto(s)
Dispersión de Semillas , Árboles , Animales , Abejas , Ecosistema , Bosques , Semillas
6.
Microsurgery ; 40(2): 189-199, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31225680

RESUMEN

BACKGROUND: Vascularised composite allo-transplantation (VCA) is emerging as a tailored approach for complex tissue reconstruction. This study focuses on the quadriceps VCA as a potential solution for tissue repair, following trauma, necrotising fasciitis/myositis, or tumor ablation. METHODS: Dissections were undertaken in 10 adult cadaveric lower limbs to characterize the blood supply to the quadriceps femoris for en bloc muscle allo-transplantation. A mock cadaveric transplantation was performed to (a) define the best neurovascular VCA design and (b) test the feasibility of the procedure. A review of 54 archival radiograph studies from the institution was also performed to further evaluate the muscle vasculature. RESULTS: In two lower limbs, the quadriceps VCA was harvested designed on the common and superficial femoral vessels and nerve, which revealed a lengthy and bloody dissection, especially of the veins, which could increase clinically with the inability to use a tourniquet for most of the dissection. However, review of our previous archival studies showed that all four quadriceps muscles are supplied within the lateral circumflex femoral angiosome. In a further eight lower limbs, the quadriceps femoris muscle group consistently received its blood supply from the lateral circumflex femoral angiosome, verified by selective lead oxide injections of this artery. The vastus medialis appeared to have a more tenous blood supply distally based on this angiosome. A successful mock cadaveric transplant was performed based on this data. CONCLUSIONS: We suggest that the best neuromuscular quadriceps VCA should be (a) designed on the lateral circumflex femoral pedicle, (b) should be raised from distal to proximal, and (c) should include the descending genicular vessels as a potential supplemental supply to vastus medialis, should all four muscles be required.


Asunto(s)
Fémur , Músculo Cuádriceps , Adulto , Aloinjertos , Cadáver , Estudios de Factibilidad , Humanos
7.
Am J Bot ; 106(5): 656-666, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31034587

RESUMEN

PREMISE: Water deficit and drought conditions are increasing in intensity, frequency, and duration in the Iberian Peninsula. We observed natural variation in leaf traits across the range of Quercus suber L. (cork oak), an ecologically important species within this region. Stomatal traits (e.g., pore length, maximum aperture) and carbon isotope composition (δ13 C) provide an opportunity to examine the integrative effects of drought and dry-season intensity on leaf development, maximum stomatal conductance, and adaptation to precipitation regimes. METHODS: Gross leaf traits (e.g., area, thickness), stomatal traits (e.g., pore length, size, aperture), and carbon isotope discrimination were measured in Q. suber leaves, and maximum stomatal conductance to water vapor (gwmax ) was calculated. Trees were sampled from nine natural populations across a climate gradient in the Iberian Peninsula, including trees from two genetic lineages. Linear mixed models compared total water deficit to leaf traits, accounting for tree and site as random effects. RESULTS: Quercus suber gross leaf morphology remained consistent across the climate gradient, but increasing water deficit was correlated with smaller stomata at the leaf level and low δ13 C at the tree level. No traits were significantly different between the two genetic lineages. CONCLUSIONS: While there were no significant differences in gross leaf morphology across the climate gradient or between the genetic lineages, stomatal traits and δ13 C responded to climate, suggesting that Q. suber can inhabit a range of environments in the Iberian Peninsula via micro-adjustments of the trait that controls water loss into the atmosphere.


Asunto(s)
Clima , Sequías , Rasgos de la Historia de Vida , Hojas de la Planta/fisiología , Quercus/fisiología , Isótopos de Carbono/análisis , Hojas de la Planta/anatomía & histología , Quercus/anatomía & histología , Estaciones del Año , España
8.
Mycorrhiza ; 27(4): 311-319, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27924430

RESUMEN

Nitrogen (N) and phosphorus (P) deposition are increasing worldwide largely due to increased fertilizer use and fossil fuel combustion. Most work with N and P deposition in natural ecosystems has focused on temperate, highly industrialized, regions. Tropical regions are becoming more developed, releasing large amounts of these nutrients into the atmosphere. Nutrient enrichment in nutrient-poor systems such as tropical montane forest can represent a relatively large shift in nutrient availability, especially for sensitive microorganisms such as arbuscular mycorrhizal fungi (AMF). These symbiotic fungi are particularly critical, given their key role in ecosystem processes affecting plant community structure and function.To better understand the consequences of nutrient deposition in plant communities, a long-term nutrient addition experiment was set up in a tropical montane forest in the Andes of southern Ecuador. In this study, we investigated the impacts of 7 years of elevated N and P on AMF root colonization potential (AMF-RCP) through a greenhouse bait plant method in which we quantified root colonization. We also examined the relationship between AMF-RCP and rarefied tree diversity.After 7 years of nutrient addition, AMF-RCP was negatively correlated with soil P, positively correlated with soil N, and positively correlated with rarefied tree diversity. Our results show that AMF in this tropical montane forest are directly affected by soil N and P concentrations, but may also be indirectly impacted by shifts in rarefied tree diversity. Our research also highlights the need to fully understand the benefits and drawbacks of using different sampling methods (e.g., AMF-RCP versus direct root sampling) to robustly examine AMF-plant interactions in the future.


Asunto(s)
Bosques , Micorrizas/fisiología , Nitrógeno/fisiología , Fósforo/fisiología , Ecuador , Hongos , Raíces de Plantas/microbiología , Suelo/química , Microbiología del Suelo
9.
Ecol Appl ; 26(8): 2367-2373, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27907255

RESUMEN

Remote sensing is increasingly needed to meet the critical demand for estimates of forest structure and composition at landscape to continental scales. Hyperspectral images can detect tree canopy properties, including species identity, leaf chemistry and disease. Tree growth rates are related to these measurable canopy properties but whether growth can be directly predicted from hyperspectral data remains unknown. We used a single hyperspectral image and light detection and ranging-derived elevation to predict growth rates for 20 tropical tree species planted in experimental plots. We asked whether a consistent relationship between spectral data and growth rates exists across all species and which spectral regions, associated with different canopy chemical and structural properties, are important for predicting growth rates. We found that a linear combination of narrowband indices and elevation is correlated with standardized growth rates across all 20 tree species (R2  = 53.70%). Although wavelengths from the entire visible-to-shortwave infrared spectrum were involved in our analysis, results point to relatively greater importance of visible and near-infrared regions for relating canopy reflectance to tree growth data. Overall, we demonstrate the potential for hyperspectral data to quantify tree demography over a much larger area than possible with field-based methods in forest inventory plots.


Asunto(s)
Bosques , Árboles , Clima Tropical , Demografía , Hojas de la Planta
10.
Oecologia ; 179(1): 293-305, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25990298

RESUMEN

Adaptations to resource availability strongly shape patterns of community composition along successional gradients in environmental conditions. In the present study, we examined the extent to which variation in functional composition explains shifts in trait-based functional strategies in young tropical secondary forests during the most dynamic stage of succession (0-20 years). Functional composition of two size classes in 51 secondary forest plots was determined using community-weighted means of seven functional traits, which were intensively measured on 55 woody plant species (n = 875-1,761 individuals). Along the successional gradient in forest structure, there was a significant and consistent shift in functional strategies from resource acquisition to resource conservation. Leaf toughness and adult plant size increased significantly, while net photosynthetic capacity (A(mass)) decreased significantly during succession. Shifts in functional strategies within size classes for A(mass) and wood density also support the hypothesis that changes in functional composition are shaped by environmental conditions along successional gradients. In general, 'hard' functional traits, e.g., A(mass) and leaf toughness, linked to different facets of plant performance exhibited greater sensitivity to successional changes in forest structure than 'soft' traits, such as leaf mass area and leaf dry matter content. Our results also suggested that stochastic processes related to previous land-use history, dispersal limitation, and abiotic factors explained variation in functional composition beyond that attributed to deterministic shifts in functional strategies. Further data on seed dispersal vectors and distance and landscape configuration are needed to improve current mechanistic models of succession in tropical secondary forests.


Asunto(s)
Adaptación Biológica , Bosques , Fotosíntesis , Árboles/crecimiento & desarrollo , Clima Tropical , Humanos , Panamá , Fotosíntesis/fisiología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Árboles/fisiología
11.
Ann Plast Surg ; 74(5): 621-32, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-23038130

RESUMEN

BACKGROUND: Despite a plethora of monitoring techniques reported in the literature, only a small number of studies directly address clinical relevant end points, such as the flap salvage rate and false-positive rate. METHOD: We conducted a systematic review of current evidence regarding the postoperative monitoring of microvascular free-tissue transfer via extensive electronic and manual search and perusing databases, such as PubMed, Cochrane, American College of Physicians (ACP) Journal Club, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Excerpta Medica Database (EMBASE), and Ovid MEDLINE. The included literature (n = 184 publications) was critically appraised using March 2009 Oxford Centre for Evidence-Based Medicine definitions, focusing on the evidence for the efficacy of each technique in improving the flap salvage rate of compromised flaps. RESULT: There is a paucity of outcome-based studies, with only implanted Doppler probes, near-infrared spectroscopy, laser Doppler flowmetry, quantitative fluorimetry, and digital photography assessment using smartphones having been demonstrated in comparative studies to improve flap salvage rate. Currently, the implantable Doppler probe is the technique with the largest number of comparative studies and case series to demonstrate its effectiveness compared with clinical monitoring. CONCLUSIONS: Future studies need to evaluate the most promising monitoring techniques further with a focus on assessing clinically relevant outcomes, such as the flap salvage rate and the false-positive rate, and not simple clinical series reporting patient and physician satisfaction.


Asunto(s)
Colgajos Tisulares Libres/irrigación sanguínea , Supervivencia de Injerto , Monitoreo Fisiológico/métodos , Cuidados Posoperatorios/métodos , Temperatura Corporal , Fluorometría , Humanos , Microdiálisis , Aplicaciones Móviles , Oximetría , Fotograbar , Fotopletismografía , Espectroscopía Infrarroja Corta , Ultrasonografía Doppler
12.
Ann Plast Surg ; 73(3): 352-7, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23788141

RESUMEN

BACKGROUND: Despite the widespread use of autologous fat grafting in both reconstructive and cosmetic surgery, volume retention remains a significant problem. We aimed to critically appraise the current body of literature in fat grafting to provide a framework to guide application and comparison. METHOD: Search of scientific databases and gray literature was conducted. Articles examining nonadipogenic applications of adipose tissue and those specific to breast reconstruction were excluded. RESULTS: One hundred three articles were included. These fell under the headings of donor site, effect of infiltration solution, harvest method, effect of centrifugation, reinjection method, supplementation, the role of adipose-derived stem cells, and scaffolding. CONCLUSIONS: Despite the significant research effort in this field, there remains no consensus as to the optimum technique. This stems from the vast array of research methods and short follow-up durations. Further, extrapolation of in vitro results to clinical settings has led to many conflicting practices.


Asunto(s)
Tejido Adiposo/trasplante , Adipocitos , Humanos , Trasplante Autólogo/métodos
13.
Ann Plast Surg ; 73(1): 92-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23657044

RESUMEN

In recent times, there has been evolving interest in the fascial structure of the ear, especially in relation to otoplasty techniques. Although the fascial tissues used in these procedures are referred to as "postauricular/retroauricular fascia," the sparse anatomical studies that exist use this terminology to describe what is the adjacent thicker and more fibrous structure of the superficial temporal area continuous with the mastoid region, rather than the tissue actually used in these procedures which is adherent to the posterior surface of the ear. There are clear clinical differences in the properties of these two structures, and this study set out to identify the anatomical nature of these differences, looking in detail at the anatomy and vascularity of the fascia directly posterior and adherent to the ear itself, highlighting its unique properties, and how it interfaces with the rest of the fascia. We provide a nomenclature to differentiate the fascia adherent to the posterior of the ear (the intrinsic postauricular fascia) from the more fibrous tissues continuous with the scalp fascia (the extrinsic postauricular fascia). Clinical applications for the fascia are suggested based on the vascularity and anatomy described, and our clinical experience.


Asunto(s)
Oído Externo/anatomía & histología , Oído Externo/cirugía , Fascia/anatomía & histología , Procedimientos de Cirugía Plástica/métodos , Técnicas Cosméticas , Oído Externo/irrigación sanguínea , Fascia/irrigación sanguínea , Humanos , Labio/cirugía , Procedimientos Quirúrgicos Otológicos , Rinoplastia , Colgajos Quirúrgicos , Terminología como Asunto
14.
BMJ Open ; 14(3): e077733, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38503414

RESUMEN

INTRODUCTION: Young people aged 18-24 years old are a key demographic target for eliminating HIV transmission globally. Pre-exposure prophylaxis (PrEP), a prevention medication, reduces HIV transmission. Despite good uptake by gay and bisexual men who have sex with men, hesitancy to use PrEP has been observed in other groups, such as young people and people from ethnic minority backgrounds. The aim of this study was to explore young people's perceptions and attitudes to using PrEP. DESIGN: A qualitative transcendental phenomenological design was used. PARTICIPANTS AND SETTING: A convenience sample of 24 young people aged between 18 and 24 years was recruited from England. METHODS: Semistructured interviews and graphical elicitation were used to collect data including questions about current experiences of HIV care, awareness of using PrEP and decision-making about accessing PrEP. Thematic and visual analyses were used to identify findings. RESULTS: Young people had good levels of knowledge about HIV but poor understanding of using PrEP. In this information vacuum, negative stigma and stereotypes about HIV and homosexuality were transferred to using PrEP, which were reinforced by cultural norms portrayed on social media, television and film-such as an association between using PrEP and being a promiscuous, white, gay male. In addition, young people from ethnic minority communities appeared to have negative attitudes to PrEP use, compared with ethnic majority counterparts. This meant these young people in our study were unable to make decisions about when and how to use PrEP. CONCLUSION: Findings indicate an information vacuum for young people regarding PrEP. A strength of the study is that theoretical data saturation was reached. A limitation of the study is participants were largely from Northern England, which has low prevalence of HIV. Further work is required to explore the information needs of young people in relation to PrEP.


Asunto(s)
Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Masculino , Humanos , Adolescente , Adulto Joven , Adulto , Homosexualidad Masculina , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Etnicidad , Grupos Minoritarios , Inglaterra
15.
Clin Anat ; 26(5): 584-91, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22887027

RESUMEN

Postoperative spinal wound dehiscence is a significant complication following the posterior midline approach. It is postulated that this approach disrupts the vasculature supplying the paraspinal muscles and overlying skin. Although the spinal vasculature has been investigated previously, the smaller arterioles have not been described in the context of the posterior midline approach. Eight cadaveric neck and posterior torso specimens were dissected after injection with a radio-opaque lead oxide mixture and subsequent radiographs taken were analyzed. The deep cervical, vertebral, superficial cervical, and occipital arteries consistently supplied the cervical paraspinal muscles. The latter two arteries also vascularized the overlying skin. The deep cervical arteries were found to be located lateral to the C3 to C6 vertebrae, vulnerable to damage with the posterior approach. In the thoracic region, the superior and posterior intercostal arteries consistently supplied the spinal muscles. In all specimens, two small anastomotic vessels posterior to the laminae were found connecting the intercostal artery perforators. Both the arterial perforators and their anastomotic channels were situated in the surgical field and susceptible to damage with the posterior approach. It is likely that the disruption in spinal vasculature contributes to the multifactorial problem of wound dehiscence with the posterior midline approach.


Asunto(s)
Arteriolas/anatomía & histología , Músculos Paraespinales/irrigación sanguínea , Dehiscencia de la Herida Operatoria/etiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piel/irrigación sanguínea , Columna Vertebral/anatomía & histología
16.
Glob Chall ; 7(8): 2300002, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37635699

RESUMEN

The release of metformin, a drug used in the treatment of cancer and diabetes, from poly(2-hydroxyethyl methacrylate), pHEMA, hydrogel-based microneedle patches is demonstrated in vitro. Tuning the composition of the pHEMA hydrogels enables preparation of robust microneedle patches with mechanical properties such that they would penetrate skin (insertion force of a single microneedle to be ≈40 N). Swelling experiments conducted at 20, 35, and 60 °C show temperature-dependent degrees of swelling and diffusion kinetics. Drug release from the pHEMA hydrogel-based microneedles is fitted to various models (e.g., zero order, first order, second order). Such pHEMA microneedles have potential application for transdermal delivery of metformin for the treatment of aging, cancer, diabetes, etc.

17.
Breast Cancer Res Treat ; 134(1): 181-98, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22270931

RESUMEN

OBJECTIVE: To identify possible avenues of sparing the internal mammary artery (IMA) for coronary artery bypass grafting (CABG) in women undergoing autologous breast reconstruction with deep inferior epigastric artery perforator (DIEP) flaps. BACKGROUND: Optimal autologous reconstruction of the breast and coronary artery bypass grafting (CABG) are often mutually exclusive as they both require utilisation of the IMA as the preferred arterial conduit. Given the prevalence of both breast cancer and coronary artery disease, this is an important issue for women's health as women with DIEP flap reconstructions and women at increased risk of developing coronary artery disease are potentially restricted from receiving this reconstructive option should the other condition arise. METHODS: The largest clinical and cadaveric anatomical study (n=315) to date was performed, investigating four solutions to this predicament by correlating the precise requirements of breast reconstruction and CABG against the anatomical features of the in situ IMAs. This information was supplemented by a thorough literature review. RESULTS: Minimum lengths of the left and right IMA needed for grafting to the left-anterior descending artery are 160.08 and 177.80 mm, respectively. Based on anatomical findings, the suitable options for anastomosis to each intercostals space are offered. In addition, 87-91% of patients have IMA perforator vessels to which DIEP flaps can be anastomosed in the first- and second-intercostal spaces. CONCLUSION: We outline five methods of preserving the IMA for future CABG: (1) lowering the level of DIEP flaps to the fourth- and fifth-intercostals spaces, (2) using the DIEP pedicle as an intermediary for CABG, (3) using IMA perforators to spare the IMA proper, (4) using and end-to-side anastomosis between the DIEP pedicle and IMA and (5) anastomosis of DIEP flaps using retrograde flow from the distal IMA. With careful patient selection, we hypothesize using the IMA for autologous breast reconstruction need not be an absolute contraindication for future CABG.


Asunto(s)
Neoplasias de la Mama/cirugía , Enfermedad de la Arteria Coronaria/cirugía , Anastomosis Interna Mamario-Coronaria/métodos , Mamoplastia , Microcirugia , Adulto , Anciano , Anciano de 80 o más Años , Mama/irrigación sanguínea , Neoplasias de la Mama/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Femenino , Humanos , Incidencia , Anastomosis Interna Mamario-Coronaria/estadística & datos numéricos , Mamoplastia/estadística & datos numéricos , Arterias Mamarias/diagnóstico por imagen , Arterias Mamarias/patología , Arterias Mamarias/cirugía , Persona de Mediana Edad , Radiografía , Trasplante Autólogo
18.
Histopathology ; 61(4): 702-10, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22734806

RESUMEN

AIMS: Important prognostic factors in patients with cutaneous melanoma include primary tumour thickness/depth of invasion, ulceration and mitotic rate, and the presence of tumour cells in regional lymph nodes. More recently, features of stromal components, such as blood and lymphatic vessel density, have been suggested as additional indicators of metastatic potential. Our aim was to investigate the relationship between tumour lymphatic vessels and lymph node metastasis. METHODS AND RESULTS: Metastasizing (n = 11) and non-metastasizing (n = 11) primary melanoma samples matched for depth/thickness, mitotic rate and ulceration were examined for lymphatic vessel density (LVD) in the primary tumour, using an antibody to podoplanin. Significant differences were found between LVD (vessels/unit area) in the peripheral (5.73 ± 0.67) versus central (1.72 ± 0.42) regions of the metastasizing tumour group (P < 0.001), and between LVD in the peripheral areas of metastasizing (5.73 ± 0.67) versus non-metastasizing (4.21 ± 0.37) tumours (P < 0.01). No overall difference was found between total average LVD in the two tumour groups or between their vessel morphology. CONCLUSION: Our results show that LVD is associated with risk of lymph node metastasis. Furthermore, the ratio of peripheral LVD:central LVD is a useful marker of primary melanomas that are likely to metastasize to lymph nodes.


Asunto(s)
Linfangiogénesis/fisiología , Vasos Linfáticos/patología , Melanoma/patología , Invasividad Neoplásica/patología , Neoplasias Cutáneas/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Biopsia del Ganglio Linfático Centinela
19.
Ann Plast Surg ; 68(6): 547-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22643100

RESUMEN

BACKGROUND: Historically, dissection of the temporoparietal fascia immediately above the zygomatic arch has been avoided due to the risk of transection of the temporofrontal rami of the facial nerve. METHODS: A total of 8 fresh cadaveric hemi-faces have been dissected to investigate the relationship of the temporofrontal rami of the facial nerve to the fascial layers in the temporal region. RESULTS: The relationship of the temporofrontal rami of the facial nerve to the fascial layers in the temporal region is variable, with some deep rami coursing below the parotid-temporal fascia and other superficial rami reaching the temporoparietal fascia before entering the lateral edge of the orbicularis oculi. CONCLUSIONS: Dissection of the temporoparietal fascia immediately above the zygomatic arch may place superficial branches of the temporofrontal rami at risk.


Asunto(s)
Nervio Facial/anatomía & histología , Fascia/anatomía & histología , Órbita/anatomía & histología , Cigoma/anatomía & histología , Cadáver , Disección/métodos , Humanos , Ritidoplastia/métodos , Hueso Temporal , Músculo Temporal
20.
Ann Plast Surg ; 69(1): 3-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22627495

RESUMEN

BACKGROUND: Although preoperative imaging of perforator vasculature in planning microvascular reconstruction is commonplace, there has not been any clear demonstration of the evidence for this practice, or data comparing the many available modalities in an evidence-based approach. This article aims to provide an objective, evidence-based review of the literature on this subject. METHODS: The evidence supporting the use of various modalities of imaging was investigated by performing focused searches of the PubMed and Medline databases. The articles were ranked according to the criteria set out in March 2009 Oxford Centre for Evidence-Based Medicine definitions. Endpoints comprised objective outcome data supporting the use of imaging, including flap loss, unplanned returns to theater, operative time reduction, and surgeon-reported stress. RESULTS: The objective high level of evidence for any form of preoperative perforator imaging is low with only small number of comparative studies or case series investigating computed tomographic angiography (CTA), magnetic resonance angiography, handheld Doppler, color duplex, and classic angiography. Of all modalities, there is a growing body of level 2b evidence supporting the use of CTA. CONCLUSION: While further multicenter trials testing hard outcomes are needed to conclusively validate preoperative imaging in reconstructive surgery, sufficient evidence exists to demonstrate that preoperative imaging can statistically improve outcomes, and that CTA is the current gold standard for perforator mapping.


Asunto(s)
Microcirugia/métodos , Procedimientos de Cirugía Plástica/métodos , Cuidados Preoperatorios/métodos , Colgajos Quirúrgicos/irrigación sanguínea , Angiografía/métodos , Humanos , Angiografía por Resonancia Magnética , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler en Color
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