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1.
Proc Biol Sci ; 285(1873)2018 02 28.
Article in English | MEDLINE | ID: mdl-29491171

ABSTRACT

Given that few ecosystems on the Earth have been unaffected by humans, restoring them holds great promise for stemming the biodiversity crisis and ensuring ecosystem services are provided to humanity. Nonetheless, few studies have documented the recovery of ecosystems globally or the rates at which ecosystems recover. Even fewer have addressed the added benefit of actively restoring ecosystems versus allowing them to recover without human intervention following the cessation of a disturbance. Our meta-analysis of 400 studies worldwide that document recovery from large-scale disturbances, such as oil spills, agriculture and logging, suggests that though ecosystems are progressing towards recovery following disturbances, they rarely recover completely. This result reinforces conservation of intact ecosystems as a key strategy for protecting biodiversity. Recovery rates slowed down with time since the disturbance ended, suggesting that the final stages of recovery are the most challenging to achieve. Active restoration did not result in faster or more complete recovery than simply ending the disturbances ecosystems face. Our results on the added benefit of restoration must be interpreted cautiously, because few studies directly compared different restoration actions in the same location after the same disturbance. The lack of consistent value added of active restoration following disturbance suggests that passive recovery should be considered as a first option; if recovery is slow, then active restoration actions should be better tailored to overcome specific obstacles to recovery and achieve restoration goals. We call for a more strategic investment of limited restoration resources into innovative collaborative efforts between scientists, local communities and practitioners to develop restoration techniques that are ecologically, economically and socially viable.


Subject(s)
Biodiversity , Conservation of Natural Resources/methods , Ecosystem , Earth, Planet
2.
Ann Surg Oncol ; 24(8): 2089-2094, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28224364

ABSTRACT

BACKGROUND: Although a well-established causative relationship exists between smoking and several epithelial cancers, the association of smoking with metastatic progression in melanoma is not well studied. We hypothesized that smokers would be at increased risk for melanoma metastasis as assessed by sentinel lymph node (SLN) biopsy. METHODS: Data from the first international Multicenter Selective Lymphadenectomy Trial (MSLT-I) and the screening-phase of the second trial (MSLT-II) were analyzed to determine the association of smoking with clinicopathologic variables and SLN metastasis. RESULTS: Current smoking was strongly associated with SLN metastasis (p = 0.004), even after adjusting for other predictors of metastasis. Among 4231 patients (1025 in MSLT-I and 3206 in MSLT-II), current or former smoking was also independently associated with ulceration (p < 0.001 and p < 0.001, respectively). Compared with current smoking, never smoking was independently associated with decreased Breslow thickness in multivariate analysis (p = 0.002) and with a 0.25 mm predicted decrease in thickness. CONCLUSION: The direct correlation between current smoking and SLN metastasis of primary cutaneous melanoma was independent of its correlation with tumor thickness and ulceration. Smoking cessation should be strongly encouraged among patients with or at risk for melanoma.


Subject(s)
Melanoma/pathology , Sentinel Lymph Node/pathology , Skin Neoplasms/secondary , Smoking/adverse effects , Female , Follow-Up Studies , Humans , International Agencies , Lymph Node Excision , Lymphatic Metastasis , Male , Melanoma/etiology , Melanoma/surgery , Middle Aged , Prognosis , Prospective Studies , Sentinel Lymph Node/surgery , Sentinel Lymph Node Biopsy , Skin Neoplasms/etiology , Skin Neoplasms/pathology , Skin Neoplasms/surgery , Melanoma, Cutaneous Malignant
4.
JAMA Netw Open ; 7(2): e2354751, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38319662

ABSTRACT

Importance: While smoking is associated with a decreased incidence of cutaneous melanoma, the association of smoking with melanoma progression and death is not well defined. Objective: To determine the association of smoking with survival in patients with early-stage primary cutaneous melanoma. Design, Setting, and Participants: This cohort study performed a post hoc analysis of data derived from the randomized, multinational first and second Multicenter Selective Lymphadenectomy Trials (MSLT-I and MSLT-II). Participants were accrued for MSLT-I from January 20, 1994, to March 29, 2002; MSLT-II, from December 21, 2004, to March 31, 2014. Median follow-up was 110.0 (IQR, 53.4-120.0) months for MSLT-I and 67.6 (IQR, 25.8-110.2) months for MSLT-II. Patients aged 18 to 75 years with clinical stages I or II melanoma with a Breslow thickness of 1.00 mm or greater or Clark level IV to V and available standard prognostic and smoking data were included. Analyses were performed from October 4, 2022, to March 31, 2023. Exposure: Current, former, and never smoking. Main Outcomes and Measures: Melanoma-specific survival of patients with current, former, and never smoking status was assessed for the entire cohort and for nodal observation and among subgroups with sentinel lymph node biopsy (SLNB)-negative and SLNB-positive findings. Results: Of 6279 included patients, 3635 (57.9%) were men, and mean (SD) age was 52.7 (13.4) years. The most common tumor location was an extremity (2743 [43.7%]), and mean (SD) Breslow thickness was 2.44 (2.06) mm. Smoking status included 1077 (17.2%) current, 1694 (27.0%) former, and 3508 (55.9%) never. Median follow-up was 78.4 (IQR, 30.5-119.6) months. Current smoking was associated with male sex, younger age, trunk site, thicker tumors, tumor ulceration, and SLNB positivity. Current smoking was associated with a greater risk of melanoma-associated death by multivariable analysis for the entire study (hazard ratio [HR], 1.48 [95% CI, 1.26-1.75]; P < .001). Former smoking was not. The increased risk of melanoma-specific mortality associated with current smoking was greatest for patients with SLNB-negative melanoma (HR, 1.85 [95% CI, 1.35-2.52]; P < .001), but also present for patients with SLNB-positive melanoma (HR, 1.29 [95% CI, 1.04-1.59]; P = .02) and nodal observation (HR, 1.68 [95% CI, 1.09-2.61]; P = .02). Smoking at least 20 cigarettes/d doubled the risk of death due to melanoma for patients with SLNB-negative disease (HR, 2.06 [95% CI, 1.36-3.13]; P < .001). Conclusions and Relevance: The findings of this cohort study suggest that patients with clinical stage I and II melanoma who smoked had a significantly increased risk of death due to melanoma. Smoking status should be assessed at time of melanoma diagnosis and may be considered a risk factor for disease progression.


Subject(s)
Melanoma , Skin Neoplasms , Humans , Male , Female , Melanoma/epidemiology , Melanoma/surgery , Skin Neoplasms/epidemiology , Skin Neoplasms/surgery , Cohort Studies , Smoking/epidemiology , Tobacco Smoking
5.
Ecol Evol ; 8(15): 7500-7521, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30151166

ABSTRACT

Snakes represent a sizable fraction of vertebrate biodiversity, but until recently, data on their demography have been sparse. Consequently, generalizations regarding patterns of variation are weak and the potential for population projections is limited. We address this information gap through an analysis of spatial and temporal variation in demography (population size, annual survival, and realized population growth) of the Lake Erie Watersnake, Nerodia sipedon insularum, and a review of snake survival more generally. Our study spans a period during which the Lake Erie Watersnake was listed as threatened under the U.S. Endangered Species Act, recovered, and was delisted. We collected capture-mark-recapture data at 14 study sites over 20 years, accruing 20,000 captures of 13,800 individually marked adults. Lake Erie Watersnakes achieve extraordinary abundance, averaging 520 adults per km of shoreline (ca. 260 adult per ha) at our study sites (range = 160-1,600 adults per km; ca. 80-800 adults per ha) and surpassing population recovery and postdelisting monitoring criteria. Annual survival averages 0.68 among adult females and 0.76 among adult males, varies among sites, and is positively correlated with body size among study sites. Temporal process variance in annual survival is low, averaging 0.0011 or less than 4% of total variance; thus, stochasticity in annual survival may be of minor significance to snake extinction risk. Estimates of realized population growth indicate that population size has been stable or increasing over the course of our study. More generally, snake annual survival overlaps broadly across continents, climate zones, families, subfamilies, reproductive modes, body size categories, maturation categories, and parity categories. Differences in survival in relation to size, parity, and maturation are in the directions predicted by life history theory but are of small magnitude with much variation around median values. Overall, annual survival appears to be quite plastic, varying with food availability, habitat quality, and other ecological variables.

6.
PLoS One ; 12(2): e0171368, 2017.
Article in English | MEDLINE | ID: mdl-28158256

ABSTRACT

Global forest restoration targets have been set, yet policy makers and land managers lack guiding principles on how to invest limited resources to achieve them. We conducted a meta-analysis of 166 studies in naturally regenerating and actively restored forests worldwide to answer: (1) To what extent do floral and faunal abundance and diversity and biogeochemical functions recover? (2) Does recovery vary as a function of past land use, time since restoration, forest region, or precipitation? (3) Does active restoration result in more complete or faster recovery than passive restoration? Overall, forests showed a high level of recovery, but the time to recovery depended on the metric type measured, past land use, and region. Abundance recovered quickly and completely, whereas diversity recovered slower in tropical than in temperate forests. Biogeochemical functions recovered more slowly after agriculture than after logging or mining. Formerly logged sites were mostly passively restored and generally recovered quickly. Mined sites were nearly always actively restored using a combination of planting and either soil amendments or recontouring topography, which resulted in rapid recovery of the metrics evaluated. Actively restoring former agricultural land, primarily by planting trees, did not result in consistently faster or more complete recovery than passively restored sites. Our results suggest that simply ending the land use is sufficient for forests to recover in many cases, but more studies are needed that directly compare the value added of active versus passive restoration strategies in the same system. Investments in active restoration should be evaluated relative to the past land use, the natural resilience of the system, and the specific objectives of each project.


Subject(s)
Forests , Agriculture , Climate , Conservation of Natural Resources , Ecosystem
7.
Nat Commun ; 8: 14163, 2017 01 20.
Article in English | MEDLINE | ID: mdl-28106039

ABSTRACT

Ecosystem recovery from anthropogenic disturbances, either without human intervention or assisted by ecological restoration, is increasingly occurring worldwide. As ecosystems progress through recovery, it is important to estimate any resulting deficit in biodiversity and functions. Here we use data from 3,035 sampling plots worldwide, to quantify the interim reduction of biodiversity and functions occurring during the recovery process (that is, the 'recovery debt'). Compared with reference levels, recovering ecosystems run annual deficits of 46-51% for organism abundance, 27-33% for species diversity, 32-42% for carbon cycling and 31-41% for nitrogen cycling. Our results are consistent across biomes but not across degrading factors. Our results suggest that recovering and restored ecosystems have less abundance, diversity and cycling of carbon and nitrogen than 'undisturbed' ecosystems, and that even if complete recovery is reached, an interim recovery debt will accumulate. Under such circumstances, increasing the quantity of less-functional ecosystems through ecological restoration and offsetting are inadequate alternatives to ecosystem protection.


Subject(s)
Carbon Cycle , Ecosystem , Nitrogen Cycle , Agriculture , Biodiversity , Conservation of Natural Resources , Forests , Grassland , Mining , Wetlands
8.
Crit Rev Oncog ; 21(1-2): 75-81, 2016.
Article in English | MEDLINE | ID: mdl-27481004

ABSTRACT

Tumor-associated gangliosides have been investigated for their potential as antigenic targets for more than 35 years, culminating in the recent Food and Drug Administration approval of dinutuximab (Unituxin), an IgG antibody targeted against GD2, for the treatment of neuroblastoma in children. This review is focused on discoveries and development of therapeutic approaches involving human IgM antibodies directed against gangliosides, which occurred over the past 40 years at University of California-Los Angeles and the John Wayne Cancer Institute, where Dr. Donald Morton led the surgical oncology department until his death.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antigens, Neoplasm/immunology , Gangliosides/immunology , Immunoglobulin M/therapeutic use , Neoplasms/immunology , Neoplasms/therapy , Antibodies, Monoclonal/immunology , Antigenic Variation , Cancer Vaccines/immunology , G(M2) Ganglioside/immunology , Humans , Immunization, Passive , Immunoglobulin M/immunology , Immunotherapy , Molecular Targeted Therapy , Neoplasms/diagnosis
9.
PLoS One ; 11(1): e0146299, 2016.
Article in English | MEDLINE | ID: mdl-26730712

ABSTRACT

Body size, and, by extension, growth has impacts on physiology, survival, attainment of sexual maturity, fecundity, generation time, and population dynamics, especially in ectotherm animals that often exhibit extensive growth following attainment of sexual maturity. Frequently, growth is analyzed at the population level, providing useful population mean growth parameters but ignoring individual variation that is also of ecological and evolutionary significance. Our long-term study of Lake Erie Watersnakes, Nerodia sipedon insularum, provides data sufficient for a detailed analysis of population and individual growth. We describe population mean growth separately for males and females based on size of known age individuals (847 captures of 769 males, 748 captures of 684 females) and annual growth increments of individuals of unknown age (1,152 males, 730 females). We characterize individual variation in asymptotic size based on repeated measurements of 69 males and 71 females that were each captured in five to nine different years. The most striking result of our analyses is that asymptotic size varies dramatically among individuals, ranging from 631-820 mm snout-vent length in males and from 835-1125 mm in females. Because female fecundity increases with increasing body size, we explore the impact of individual variation in asymptotic size on lifetime reproductive success using a range of realistic estimates of annual survival. When all females commence reproduction at the same age, lifetime reproductive success is greatest for females with greater asymptotic size regardless of annual survival. But when reproduction is delayed in females with greater asymptotic size, lifetime reproductive success is greatest for females with lower asymptotic size when annual survival is low. Possible causes of individual variation in asymptotic size, including individual- and cohort-specific variation in size at birth and early growth, warrant further investigation.


Subject(s)
Body Size/physiology , Colubridae/physiology , Ecosystem , Physiological Phenomena/physiology , Age Factors , Algorithms , Animals , Body Temperature Regulation/physiology , Female , Fertility/physiology , Lakes , Male , Models, Biological , Reproduction/physiology , Sex Factors , Temperature
10.
Med Hypotheses ; 80(4): 425-30, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23375413

ABSTRACT

Natural anti-tumor IgM antibodies are prevalent in the serum of cancer patients and normal subjects. Extensive research has been directed toward the ultimate goal of achieving a therapeutic effect from these antibodies either augmented by vaccination or by passive infusion. To date, the therapeutic effects have been limited. This thesis asserts that thiols within solid tumors reduce pentameric IgM to monomeric or other subunit form resulting in inactivation of its complement fixing and cross linking apoptosis inducing properties. A rationale for this normal physiological inactivation mechanism, possibly necessary for wound healing and pregnancy, is proposed along with therapeutic approaches, which would potentially suppress IgM inactivation.


Subject(s)
Antibodies, Neoplasm/immunology , Apoptosis/immunology , Immunity, Innate/immunology , Immunoglobulin M/immunology , Models, Immunological , Neoplasms/immunology , Sulfhydryl Compounds/immunology , Animals , Humans , Neoplasms/pathology
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