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1.
Sci Rep ; 14(1): 16772, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039098

RESUMO

Secondary tropical forests are at the forefront of deforestation pressures. They store large amounts of carbon, which, if compensated for to avoid net emissions associated with conversion to non-forest uses, may help advance tropical forest conservation. We measured above- and below-ground carbon stocks down to 1 m soil depth across a secondary forest and in oil palm plantations in Malaysia. We calculated net carbon losses when converting secondary forests to oil palm plantations and estimated payments to avoid net emissions arising from land conversion to a 22-year oil palm rotation, based on land opportunity costs per hectare. We explored how estimates would vary between forests by also extracting carbon stock data for primary forest from the literature. When tree and soil carbon was accounted for, payments of US$18-51 tCO2-1 for secondary forests and US$14-40 tCO2-1 for primary forest would equal opportunity costs associated with oil palm plantations per hectare. If detailed assessments of soil carbon were not accounted for, payments to offset opportunity costs would need to be considerably higher for secondary forests (US$28-80 tCO2-1). These results show that assessment of carbon stocks down to 1 m soil depth in tropical forests can substantially influence the estimated value of avoided-emission payments.


Assuntos
Carbono , Conservação dos Recursos Naturais , Florestas , Solo , Clima Tropical , Solo/química , Carbono/análise , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Árvores , Malásia
2.
Glob Chang Biol ; 27(13): 3066-3078, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33949757

RESUMO

Trees in northern latitude ecosystems are projected to experience increasing drought stress as a result of rising air temperatures and changes in precipitation patterns in northern latitude ecosystems. However, most drought-related studies on high-latitude boreal forests (>50°N) have been conducted in North America, with few studies quantifying the response in European and Eurasian boreal forests. Here, we tested how daily whole-tree transpiration (Q, Liters day-1 ) and Q normalized for mean daytime vapor pressure deficit (QDZ , Liters day-1 kPa-1 ) were affected by the historic 2018 drought in Europe. More specifically, we examined how tree species, size, and topographic position affected drought response in high-latitude mature boreal forest trees. We monitored 30 Pinus sylvestris (pine) and 30 Picea abies (spruce) trees distributed across a topographic gradient in northern Sweden. In general, pine showed a greater QDZ control compared to spruce during periods of severe drought (standardized precipitation-evapotranspiration index: SPEI < -1.5), suggesting that the latter are more sensitive to drought. Overall, QDZ reductions (using non-drought QDZ as reference) were less pronounced in larger trees during severe drought, but there was a species-specific pattern: QDZ reductions were greater in pine trees at high elevations and greater in spruce trees at lower elevations. Despite lower QDZ during severe drought, drought spells were interspersed with small precipitation events and overcast conditions, and QDZ returned to pre-drought conditions relatively quickly. This study highlights unique species-specific responses to drought, which are additionally driven by a codependent interaction among tree size, relative topographic position, and unique regional climate conditions.


Assuntos
Picea , Taiga , Secas , Ecossistema , Europa (Continente) , Florestas , América do Norte , Suécia , Árvores
3.
Hum Ecol Interdiscip J ; 49(3): 239-247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33343057

RESUMO

Forests have long been locations of contestation between people and state bureaucracies, and among the knowledge frameworks of local users, foresters, ecologists, and conservationists. An essential framing of the debate has been between the categories of primary and secondary forest. In this introduction to a collection of papers that address the questions of what basis, in what sense, and for whom primary forest is 'primary' and secondary forest is 'secondary,' and whether these are useful distinctions, we outline this debate and propose a new conceptual model that departs from the simple binary of primary and secondary forests. Rather, we propose that attention should be given to the nature of the disturbance that may alter forest ecology, the forms of regeneration that follow, and the governance context within which this takes place.

4.
Glob Chang Biol ; 25(9): 2900-2914, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31166650

RESUMO

There is evidence that anthropogenic nitrogen (N) deposition enhances carbon (C) sequestration in boreal forest soils. However, it is unclear how free-living saprotrophs (bacteria and fungi, SAP) and ectomycorrhizal (EM) fungi responses to N addition impact soil C dynamics. Our aim was to investigate how SAP and EM communities are impacted by N enrichment and to estimate whether these changes influence decay of litter and humus. We conducted a long-term experiment in northern Sweden, maintained since 2004, consisting of ambient, low N additions (0, 3, 6, and 12 kg N ha-1  year-1 ) simulating current N deposition rates in the boreal region, as well as a high N addition (50 kg N ha-1  year-1 ). Our data showed that long-term N enrichment impeded mass loss of litter, but not of humus, and only in response to the highest N addition treatment. Furthermore, our data showed that EM fungi reduced the mass of N and P in both substrates during the incubation period compared to when only SAP organisms were present. Low N additions had no effect on microbial community structure, while the high N addition decreased fungal and bacterial biomasses and altered EM fungi and SAP community composition. Actinomycetes were the only bacterial SAP to show increased biomass in response to the highest N addition. These results provide a mechanistic understanding of how anthropogenic N enrichment can influence soil C accumulation rates and suggest that current N deposition rates in the boreal region (≤12 kg N ha-1  year-1 ) are likely to have a minor impact on the soil microbial community and the decomposition of humus and litter.


Assuntos
Micorrizas , Nitrogênio , Carbono , Solo , Microbiologia do Solo , Suécia
5.
Angew Chem Int Ed Engl ; 58(8): 2241-2245, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30589173

RESUMO

Owing to the strong nonpolar bonds involved, selective C-H functionalization of methane and ethane to esters remains a challenge for molecular homogeneous chemistry. We report that the computationally predicted main-group p-block SbV (TFA)5 complex selectively functionalizes the C-H bonds of methane and ethane to the corresponding mono and/or diol trifluoroacetate esters at 110-180 °C with yields for ethane of up to 60 % with over 90 % selectivity. Experimental and computational studies support a unique mechanism that involves SbV -mediated C-H activation followed by functionalization of a SbV -alkyl intermediate.

6.
Nat Ecol Evol ; 2(9): 1443-1448, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30013133

RESUMO

Effective societal responses to rapid climate change in the Arctic rely on an accurate representation of region-specific ecosystem properties and processes. However, this is limited by the scarcity and patchy distribution of field measurements. Here, we use a comprehensive, geo-referenced database of primary field measurements in 1,840 published studies across the Arctic to identify statistically significant spatial biases in field sampling and study citation across this globally important region. We find that 31% of all study citations are derived from sites located within 50 km of just two research sites: Toolik Lake in the USA and Abisko in Sweden. Furthermore, relatively colder, more rapidly warming and sparsely vegetated sites are under-sampled and under-recognized in terms of citations, particularly among microbiology-related studies. The poorly sampled and cited areas, mainly in the Canadian high-Arctic archipelago and the Arctic coastline of Russia, constitute a large fraction of the Arctic ice-free land area. Our results suggest that the current pattern of sampling and citation may bias the scientific consensuses that underpin attempts to accurately predict and effectively mitigate climate change in the region. Further work is required to increase both the quality and quantity of sampling, and incorporate existing literature from poorly cited areas to generate a more representative picture of Arctic climate change and its environmental impacts.


Assuntos
Mudança Climática , Regiões Árticas , Ecossistema , Viés de Seleção , Análise Espacial
7.
Environ Sci Pollut Res Int ; 24(34): 26160-26171, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28386895

RESUMO

Increased atmospheric nitrogen (N) deposition is known to alter ecosystem carbon source-sink dynamics through changes in soil CO2 fluxes. However, a limited number of experiments have been conducted to assess the effects of realistic N deposition in the Mediterranean Basin, and none of them have explored the effects of N addition on soil respiration (R s ). To fill this gap, we assessed the effects of N supply on R s dynamics in the following two Mediterranean sites: Capo Caccia (Italy), where 30 kg ha-1 year-1 was supplied for 3 years, and El Regajal (Spain), where plots were treated with 10, 20, or 50 kg N ha-1 year-1 for 8 years. Results show a complex, non-linear response of soil respiration (R s ) to N additions with R s overall increasing at Capo Caccia and decreasing at El Regajal. This suggests that the response of R s to N addition depends on dose and duration of N supply, and the existence of a threshold above which the N introduced in the ecosystem can affect the ecosystem's functioning. Soil cover and seasonality of precipitations also play a key role in determining the effects of N on R s as shown by the different responses observed across seasons and in bare soil vs. the soil under canopy of the dominant species. These results show how increasing rates of N addition may influence soil C dynamics in semiarid ecosystems in the Mediterranean Basin and represent a valuable contribution for the understanding and the protection of Mediterranean ecosystems.


Assuntos
Ecossistema , Nitrogênio/química , Solo/química , Sequestro de Carbono , Itália , Nitrogênio/metabolismo , Plantas , Estações do Ano , Microbiologia do Solo , Espanha
8.
Ecology ; 97(4): 1012-22, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27220217

RESUMO

The central role that ectomycorrhizal (EM) symbioses play in the structure and function of boreal forests pivots around the common assumption that carbon (C) and nitrogen (N) are exchanged at rates favorable for plant growth. However, this may not always be the case. It has been hypothesized that the benefits mycorrhizal fungi convey to their host plants strongly depends upon the availability of C and N, both of which are rapidly changing as a result of intensified human land use and climate change. Using large-scale shading and N addition treatments, we assessed the independent and interactive effects of changes in C and N supply on the transfer of N in intact EM associations with -15 yr. old Scots pine trees. To assess the dynamics of N transfer in EM symbioses, we added trace amounts of highly enriched 5NO3(-) label to the EM-dominated mor-layer and followed the fate of the 15N label in tree foliage, fungal chitin on EM root tips, and EM sporocarps. Despite no change in leaf biomass, shading resulted in reduced tree C uptake, ca. 40% lower fungal biomass on EM root tips, and greater 15N label in tree foliage compared to unshaded control plots, where more 15N label was found in fungal biomass on EM colonized root tips. Short-term addition of N shifted the incorporation of 15N label from EM fungi to tree foliage, despite no significant changes in below-ground tree C allocation to EM fungi. Contrary to the common assumption that C and N are exchanged at rates favorable for plant growth, our results show for the first time that under N-limited conditions greater C allocation to EM fungi in the field results in reduced, not increased, N transfer to host trees. Moreover, given the ubiquitous nature of mycorrhizal symbioses, our results stress the need to incorporate mycorrhizal dynamics into process-based ecosystem models to better predict forest C and N cycles in light of global climate change.


Assuntos
Carbono/metabolismo , Florestas , Micorrizas/fisiologia , Nitrogênio/metabolismo , Pinus sylvestris/microbiologia , Árvores/microbiologia , Pinus sylvestris/fisiologia , Simbiose , Árvores/fisiologia
10.
J Hand Surg Am ; 40(4): 773-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25746143

RESUMO

PURPOSE: A retrospective review of a single institution's experience with idiopathic carpal tunnel syndrome (CTS) in children and adolescents was performed to evaluate management and outcomes in an effort to establish a treatment protocol. METHODS: All patients diagnosed with idiopathic CTS from ages 1 to 16 years of age between 1983 and 2013 were reviewed. The results of diagnostic testing and efficacy of therapeutic interventions were analyzed. The Boston Carpal Tunnel Questionnaire was sent to all patients following medical or surgical management. RESULTS: A total of 20 patients with 31 involved wrists met criteria for entrance into the study. The mean age at diagnosis was 14.4 years. Orthosis fabrication was used as the initial treatment in 30 of 31 wrists and was successful in completely alleviating symptoms in 9 of 30 wrists. A steroid injection was performed in 11 of 31 wrists, completely relieving symptoms in 5 of 11 wrists. Carpal tunnel release was performed in 10 of 31 wrists. Following surgery, patients had complete relief of symptoms in 5 of 10 wrists and partial relief of symptoms in 5 of 10 wrists. Questionnaire response incidence was 55% (11 of 20), with an average long-term follow-up of 17.6 years. Eight questionnaire respondents continued to have mild to moderate symptoms while performing activities of daily living. CONCLUSIONS: Once metabolic, anatomical, and hereditary causes of pediatric CTS are ruled out, a reasonable treatment course should follow that of adults with orthosis fabrication, followed by injection, and then surgery for those that are refractory to nonsurgical treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.


Assuntos
Síndrome do Túnel Carpal/terapia , Atividades Cotidianas , Adolescente , Corticosteroides/administração & dosagem , Síndrome do Túnel Carpal/etiologia , Síndrome do Túnel Carpal/cirurgia , Criança , Pré-Escolar , Terapia Combinada , Feminino , Humanos , Injeções Intra-Articulares , Masculino , Mucopolissacaridoses/complicações , Aparelhos Ortopédicos , Estudos Retrospectivos , Resultado do Tratamento , Articulação do Punho/efeitos dos fármacos
11.
Sci Rep ; 5: 8280, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25655192

RESUMO

Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the (15)N:(14)N ratio of soil organic matter across climate gradients provide key insights into understanding global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in (15)N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ(15)N was invariant with MAT. At the global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ(15)N showed no consistent trends across global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and global budgets of gaseous N loss.

12.
Glob Chang Biol ; 21(8): 3169-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25711504

RESUMO

It is proposed that carbon (C) sequestration in response to reactive nitrogen (Nr ) deposition in boreal forests accounts for a large portion of the terrestrial sink for anthropogenic CO2 emissions. While studies have helped clarify the magnitude by which Nr deposition enhances C sequestration by forest vegetation, there remains a paucity of long-term experimental studies evaluating how soil C pools respond. We conducted a long-term experiment, maintained since 1996, consisting of three N addition levels (0, 12.5, and 50 kg N ha(-1) yr(-1) ) in the boreal zone of northern Sweden to understand how atmospheric Nr deposition affects soil C accumulation, soil microbial communities, and soil respiration. We hypothesized that soil C sequestration will increase, and soil microbial biomass and soil respiration will decrease, with disproportionately large changes expected compared to low levels of N addition. Our data showed that the low N addition treatment caused a non-significant increase in the organic horizon C pool of ~15% and a significant increase of ~30% in response to the high N treatment relative to the control. The relationship between C sequestration and N addition in the organic horizon was linear, with a slope of 10 kg C kg(-1) N. We also found a concomitant decrease in total microbial and fungal biomasses and a ~11% reduction in soil respiration in response to the high N treatment. Our data complement previous data from the same study system describing aboveground C sequestration, indicating a total ecosystem sequestration rate of 26 kg C kg(-1) N. These estimates are far lower than suggested by some previous modeling studies, and thus will help improve and validate current modeling efforts aimed at separating the effect of multiple global change factors on the C balance of the boreal region.


Assuntos
Sequestro de Carbono , Carbono/análise , Nitrogênio/análise , Taiga , Ecossistema , Solo/química , Microbiologia do Solo , Suécia
13.
J Plast Reconstr Aesthet Surg ; 68(3): 395-402, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25488326

RESUMO

BACKGROUND: Enhanced recovery after surgery (ERAS) pathways have been shown in multiple surgical specialties to decrease hospital length of stay (LOS) after surgery, but they have not been described for patients undergoing microvascular breast reconstruction. STUDY DESIGN: A standardized ERAS pathway was developed through multidisciplinary collaboration which addressed all phases of surgical care for patients undergoing free-flap breast reconstruction using an abdominal donor site. Two surgeons used the ERAS pathway, and results were compared with a historical cohort of the same 2 surgeons' patients treated by traditional care after surgery (TRAS). All patients underwent surgery between September 2010 and September 2013. The primary outcome measure was hospital LOS. RESULTS: A total of 100 patients were analyzed: 49 in the ERAS cohort, and 51 in the TRAS cohort, with a total of 181 flaps. Mean hospital LOS was shorter with ERAS than TRAS (3.9 vs 5.5 days; P<0.001). Total inpatient postoperative opioid usage for the first 3 days, in oral morphine equivalents, was less for ERAS than TRAS (167.3 vs 574.3 mg; P<0.001), a decrease of 71%, with similar pain scores for the 2 groups. Overall 30-day major complication rates were not significantly different between the groups (P=0.21). CONCLUSIONS: The initiation of an ERAS pathway significantly decreased hospital LOS in our study. The pathway also significantly decreased the amount of opioids used postoperatively by 71%, without a consequent increase in patient-reported pain.


Assuntos
Tempo de Internação/estatística & dados numéricos , Mamoplastia/métodos , Microcirurgia , Retalhos Cirúrgicos , Cicatrização/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Manejo da Dor , Medição da Dor , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
14.
Ecol Evol ; 4(15): 3015-26, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25247059

RESUMO

Although it is well known that nitrogen (N) additions strongly affect ectomycorrhizal (EM) fungal community composition, less is known about how different N application rates and duration of N additions affect the functional role EM fungi play in the forest N cycle.We measured EM sporocarp abundance and species richness as well as determined the δ (15)N in EM sporocarps and tree foliage in two Pinus sylvestris forests characterized by short- and long-term N addition histories and multiple N addition treatments. After 20 and 39 years of N additions, two of the long-term N addition treatments were terminated, thereby providing a unique opportunity to examine the temporal recovery of EM sporocarps after cessation of high N loading.In general, increasing N availability significantly reduced EM sporocarp production, species richness, and the amount of N retained in EM sporocarps. However, these general responses were strongly dependent on the application rate and duration of N additions. The annual addition of 20 kg·N·ha(-1) for the past 6 years resulted in a slight increase in the production and retention of N in EM sporocarps, whereas the addition of 100 kg·N·ha(-1)·yr(-1) during the same period nearly eliminated EM sporocarps. In contrast, long-term additions of N at rates of ca. 35 or 70 kg·N·ha(-1)·yr(-1) for the past 40 years did not eliminate tree carbon allocation to EM sporocarps, although there was a decrease in the abundance and a shift in the dominant EM sporocarp taxa. Despite no immediate recovery, EM sporocarp abundance and species richness approached those of the control 20 years after terminating N additions in the most heavily fertilized treatment, suggesting a recovery of carbon allocation to EM sporocarps after cessation of high N loading.Our results provide evidence for a tight coupling between tree carbon allocation to and N retention in EM sporocarps and moreover highlight the potential use of δ (15)N in EM sporocarps as a relative index of EM fungal sink strength for N. However, nitrogen additions at high dosage rates or over long time periods appear to disrupt this feedback, which could have important ramifications on carbon and nitrogen dynamics in these forested ecosystems.

16.
Plast Reconstr Surg Glob Open ; 1(9): e81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25289275

RESUMO

SUMMARY: Proximal, posterior thigh wounds from oncologic or traumatic defects can be difficult wounds to reconstruct if local flap options have been sacrificed during the trauma or oncologic resection. Free flap options to cover these defects are also difficult because of the lack of convenient recipient vessels in the region. The authors present 2 cases (oncologic and traumatic) wherein a myocutaneous anterolateral thigh (ALT) flap was harvested and tunneled from the anterior muscle compartment to the posterior muscle compartment of the thigh through a medially based transmuscular tunnel, decreasing the required pedicle distance to the wound. This technique of transmuscular tunneling of the ALT flap expands the indications and utility of the ALT flap to cover posterior thigh wounds.

17.
Am J Ind Med ; 54(9): 672-80, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21557282

RESUMO

BACKGROUND: Our goal was to examine the effect of the World Trade Center (WTC) attack and subsequent New York City Fire Department (FDNY) rescue/recovery activities on firefighter retirements. We also analyzed the financial impact associated with the increased number and proportion of service-connected "accidental" disability retirements on the FDNY pension system. METHODS: A total of 7,763 firefighters retired between 9/11/1994 and 9/10/2008. We compared the total number of retirements and the number and proportion of accidental disability retirements 7 years before and 7 years after the WTC attack. We categorized WTC-related accidental disability retirements by medical cause and worked with the New York City Office of the Actuary to approximate the financial impact by cause. RESULTS: In the 7 years before 9/11 there were 3,261 retirements, 48% (1,571) of which were accidental disability retirements. In the 7 years after 9/11, there were 4,502 retirements, 66% (2,970) were accidental disability retirements, of which 47% (1,402) were associated with WTC-related injuries or illnesses. After 9/11, the increase in accidental disability retirements was, for the most part, due to respiratory-related illnesses. Additional increases were attributed to psychological-related illnesses and musculoskeletal injuries incurred at the WTC site. Pension benefits associated with WTC-related accidental disability retirements have produced an increased financial burden of over $826 million on the FDNY pension system. CONCLUSIONS: The WTC attacks affected the health of the FDNY workforce resulting in more post-9/11 retirements than expected, and a larger proportion of these retirees with accidental disability pensions.


Assuntos
Bombeiros/estatística & dados numéricos , Pneumopatias/epidemiologia , Pensões/estatística & dados numéricos , Aposentadoria/estatística & dados numéricos , Adulto , Avaliação da Deficiência , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia
18.
Clin Exp Immunol ; 164 Suppl 1: 27-30, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21447128

RESUMO

Anti-neutrophil cytoplasmic antibodies (ANCA) have been associated with a spectrum of vasculitis that includes granulomatous polyangiitis (formerly known as Wegener's granulomatosis), microscopic polyangiitis, the Churg-Strauss syndrome, primary pauciimmune necrotizing and crescentic glomerulonephritis and related forms of vasculitis. In vitro, in vivo and clinical evidence support the conclusion that ANCA participate in the pathophysiology of this disease spectrum. Rituximab is a potent tool that can interrupt B cell-mediated immunity without major compromise of T cell-mediated immunity. Thus, it has great appeal as a tool to interrupt antibody-mediated autoimmune disease. The results of two prospective randomized trials confirm that rituximab can be effective as part of induction therapy for active ANCA-associated vasculitis. The safety profile for rituximab appears favourable relative to cyclophosphamide and steroids. However, there remain many patients who require individualized adjustments of ancillary therapy, as breakthrough disease, relapses and infectious complications do occur. Based on our current knowledge, rituximab should now be incorporated as part of induction therapy in many patients with ANCA-associated vasculitis. However, more work is needed to determine how rituximab may best be integrated into the overall immunosuppression of these patients.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Anticorpos Monoclonais Murinos/uso terapêutico , Fatores Imunológicos/uso terapêutico , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Feminino , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/imunologia , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Indução de Remissão , Rituximab , Resultado do Tratamento
19.
Mycorrhiza ; 21(6): 465-471, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21210158

RESUMO

Despite their prominent role for tree growth, few studies have examined the occurrence of ectomycorrhizal fungi in lowland, seasonally dry tropical forests (SDTF). Although fruiting bodies of boletes have been observed in a dry tropical forest on the Northern Yucatan Peninsula, Mexico, their occurrence is rare and their mycorrhizal status is uncertain. To determine the trophic status (mycorrhizal vs. saprotrophic) of these boletes, fruiting bodies were collected and isotopically compared to known saprotrophic fungi, foliage, and soil from the same site. Mean δ(15)N and δ(13)C values differed significantly between boletes and saprotrophic fungi, with boletes 8.0‰ enriched and 2.5‰ depleted in (15)N and (13)C, respectively relative to saprotrophic fungi. Foliage was depleted in (13)C relative to both boletes and saprotrophic fungi. Foliar δ(15)N values, on the other hand, were similar to saprotrophic fungi, yet were considerably lower relative to bolete fruiting bodies. Results from this study provide the first isotopic evidence of ectomycorrhizal fungi in lowland SDTF and emphasize the need for further research to better understand the diversity and ecological importance of ectomycorrhizal fungi in these forested ecosystems.


Assuntos
Isótopos de Carbono/análise , Classificação/métodos , Fungos/classificação , Fungos/isolamento & purificação , Micorrizas/classificação , Micorrizas/isolamento & purificação , Isótopos de Nitrogênio/análise , Árvores/microbiologia , Carpóforos/química , Carpóforos/classificação , Carpóforos/crescimento & desenvolvimento , Carpóforos/isolamento & purificação , Fungos/química , Fungos/crescimento & desenvolvimento , México , Micorrizas/química , Micorrizas/crescimento & desenvolvimento , Microbiologia do Solo , Clima Tropical
20.
J Am Coll Surg ; 211(4): 485-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20822739

RESUMO

BACKGROUND: Fast-track (FT) postoperative protocols have been shown to be highly beneficial in open colectomy. Some have questioned the necessity of an FT protocol in the setting of laparoscopic colectomy because hospital stays are short and morbidity is low compared with open surgery. We set out to determine whether an FT protocol has any utility in the setting of elective laparoscopic colectomy. STUDY DESIGN: A retrospective review was conducted on a cohort of 334 patients who underwent elective laparoscopic sigmoid resection for diverticulitis from 1998 to 2008, at Mayo Clinic, a tertiary care center in Rochester, MN. There were 235 patients who were managed with traditional postoperative care, and 99 who were managed with an FT protocol initiated in 2006. The main outcomes measures were time to soft diet, length of stay, overall morbidity, and readmission rate. RESULTS: Times to soft diet (mean 2.3 vs 3.6 days), and first bowel movement (mean 2.6 vs 3.5 days) were shorter in the FT group (p < 0.001). The median lengths of stay were 3 days (interquartile range 3 to 4 days) and 5 days (interquartile range 4 to 6 days) for the FT and non-FT groups, respectively (p < 0.001). Morbidity was significantly lower in the FT group compared with the non-FT group (15.2% vs 25.5%, p < 0.03). The 30-day readmission rate was 2.9% for the FT group and 7.6% for the non-FT group (p = NS). There were no deaths in either group. CONCLUSIONS: Even in patients undergoing laparoscopic colectomy, FT protocols further improve the speed of gastrointestinal recovery, shorten the length of stay, and decrease morbidity.


Assuntos
Colectomia , Doença Diverticular do Colo/cirurgia , Protocolos Clínicos , Colo Sigmoide/cirurgia , Convalescença , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Laparoscopia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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