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1.
Nat Plants ; 10(6): 1039-1051, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38816498

RESUMO

Cotton (Gossypium hirsutum L.) is the key renewable fibre crop worldwide, yet its yield and fibre quality show high variability due to genotype-specific traits and complex interactions among cultivars, management practices and environmental factors. Modern breeding practices may limit future yield gains due to a narrow founding gene pool. Precision breeding and biotechnological approaches offer potential solutions, contingent on accurate cultivar-specific data. Here we address this need by generating high-quality reference genomes for three modern cotton cultivars ('UGA230', 'UA48' and 'CSX8308') and updating the 'TM-1' cotton genetic standard reference. Despite hypothesized genetic uniformity, considerable sequence and structural variation was observed among the four genomes, which overlap with ancient and ongoing genomic introgressions from 'Pima' cotton, gene regulatory mechanisms and phenotypic trait divergence. Differentially expressed genes across fibre development correlate with fibre production, potentially contributing to the distinctive fibre quality traits observed in modern cotton cultivars. These genomes and comparative analyses provide a valuable foundation for future genetic endeavours to enhance global cotton yield and sustainability.


Assuntos
Genoma de Planta , Gossypium , Melhoramento Vegetal , Gossypium/genética , Gossypium/crescimento & desenvolvimento , Melhoramento Vegetal/métodos , Fibra de Algodão , Variação Genética , Fenótipo
2.
Cureus ; 16(1): e51864, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38327927

RESUMO

A complete ureteral triplication is a rare congenital urinary tract anomaly that typically presents in childhood. This is an exceedingly rare case of an adult male presenting with right pyelonephritis and flank pain who was subsequently diagnosed with a right type I ureteral triplication associated with an obstructed megaureter inserted into the prostatic urethra. This patient underwent a right partial nephrectomy to remove the dilated and non-functional upper renal segment leaving behind a blind ending ureteral remnant. Following partial nephrectomy, the patient's flank pain and recurrent urinary tract infections resolved despite persistent dilation of the ureteral remnant. While a standard method of surgical management for a triplicated ureter has not been well established in the adult population, in this case, partial nephrectomy has demonstrated efficacy while avoiding more invasive procedures.

3.
Case Rep Urol ; 2022: 9966553, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246551

RESUMO

Introduction: Bladder neck abscesses are rare urologic pathologies with very few cases published in modern literature. This report explores a case of a bladder neck mass incidentally found on computed tomography (CT) imaging in a patient with an iliopsoas abscess. Case Presentation. We present a case of a 60-year-old woman who was recently treated for sepsis secondary to an iliopsoas abscess in July of 2022. A CT scan revealed an indeterminate structure in the posterior inferior left paramedian bladder wall. During a cystoscopy with transurethral resection of the mass, an abscess was uncovered and evacuated. A postoperative Foley catheter was left in place, and the patient recovered without any complications. Conclusion: At the time of publication, the patient feels well and denies pain or lower urinary tract symptoms. Although bladder abscesses are exceptionally rare, incidental findings during cystoscopy may warrant further investigation in patients with comorbid abscesses.

4.
Cureus ; 13(9): e18185, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34707958

RESUMO

Purpose To examine dosimetric and clinical outcomes for Cs-131 radioactive seed implant compared to Pd-103 and I-125.  Background/Significance Cs-131 is a novel isotope with relatively short half-life (9.7 days) that may have clinical advantages in seed implant treatments of prostate cancers. There may be a shorter duration of symptoms and increased PSA control rates. Methods We performed a retrospective study in which clinical and dosimetric outcomes were compared for 186 prostate implants performed over a ten-year time period at three different Ascension hospitals. Isotopes that were used included Cs-131 (n=66; half-life 9.7 days), I-125 (n=60; half-life 60 days), and Pd-103 (n=60; half-life 17 days) Results The implants used standard radiation dosages. These were 145 Gy for I-125 alone or 109 Gy when combined with external beam radiation. In the case of Cs-131 used alone, the dose was 115 Gy or 85 Gy when combined with an external beam. For Pd-103, 125 Gy was used for monotherapy and 90 Gy when combined with an external beam. The Cs-131 dosimetry was found to be similar to I-125 and Pd-103 on a quantitative basis. However, there was better homogeneity, and the delivered activity per seed and the number of seeds employed were greater compared to other isotopes. We compared the corrected total source strengths (i.e. normalized to sample mean values) and were able to demonstrate similar distributions for the three isotopes. Dosimetric analysis also suggested there was superior homogeneity with Cs-131. The median PSA value at 60 months was 0.11 ng/ml. There were only a few PSA failures in the three groups of cases, nonetheless, the Cs-131 had the fewest.  Conclusions One attractive option for men with early-stage prostate cancer is interstitial brachytherapy. The use of the shorter-acting Cs-131 isotope may be expected to have dose-related side effects that resolve more rapidly. This series suggests a trend for improved PSA control outcomes for Cs-131 patients compared with I-125 and Pd-103.

5.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260382

RESUMO

Despite decades of policy that strives to reduce nutrient and sediment export from agricultural fields, surface water quality in intensively managed agricultural landscapes remains highly degraded. Recent analyses show that current conservation efforts are not sufficient to reverse widespread water degradation in Midwestern agricultural systems. Intensifying row crop agriculture and increasing climate pressure require a more integrated approach to water quality management that addresses diverse sources of nutrients and sediment and off-field mitigation actions. We used multiobjective optimization analysis and integrated three biophysical models to evaluate the cost-effectiveness of alternative portfolios of watershed management practices at achieving nitrate and suspended sediment reduction goals in an agricultural basin of the Upper Midwestern United States. Integrating watershed-scale models enabled the inclusion of near-channel management alongside more typical field management and thus directly the comparison of cost-effectiveness across portfolios. The optimization analysis revealed that fluvial wetlands (i.e., wide, slow-flowing, vegetated water bodies within the riverine corridor) are the single-most cost-effective management action to reduce both nitrate and sediment loads and will be essential for meeting moderate to aggressive water quality targets. Although highly cost-effective, wetland construction was costly compared to other practices, and it was not selected in portfolios at low investment levels. Wetland performance was sensitive to placement, emphasizing the importance of watershed scale planning to realize potential benefits of wetland restorations. We conclude that extensive interagency cooperation and coordination at a watershed scale is required to achieve substantial, economically viable improvements in water quality under intensive row crop agricultural production.


Assuntos
Agricultura/economia , Agricultura/normas , Análise Custo-Benefício , Modelos Teóricos , Qualidade da Água/normas , Orçamentos , Comportamento Cooperativo , Geografia , Minnesota
6.
Transfusion ; 61(1): 24-28, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33084098

RESUMO

BACKGROUND: Greater use of unrelated donors to support hematopoietic cell transplantation can be hampered by unavailability of registrants when identified as potential candidates for donation. METHODS: Multivariate analysis was performed to identify donor factors associated with availability for verification of human leukocyte antigen typing (VT) needed before donor activation. All VT requests for registrants on the Canadian Blood Services Stem Cell Registry between 1 January and 31 December 2018 were reviewed (n = 1358). RESULTS: Potential donors identified by transplant centers were categorized as available at the time of VT but ineligible for medical or other reasons (n = 130 and excluded from further analysis), available (n = 622) or unavailable (n = 566) due to scheduling, loss of interest, and/or inability to contact. With multivariate analysis, registrants who previously donated blood, those recruited online or from blood donation clinics, and a shorter interval between registration and VT request were significantly correlated with increased donor availability. Donor sex and geographic location, however, displayed no correlation. CONCLUSION: Online registration and recruitment at whole blood donation centers should be enhanced to increase the availability of registrants at VT. More insight is needed to maintain registrant availability following community in-person recruitment events, especially if the interval between registration and activation is prolonged. Recruitment of male registrants who are well informed should not negatively impact availability.


Assuntos
Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/imunologia , Teste de Histocompatibilidade/métodos , Células-Tronco de Sangue Periférico/imunologia , Doadores de Tecidos/provisão & distribuição , Bancos de Sangue , Doadores de Sangue , Canadá , Feminino , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Análise Multivariada , Sistema de Registros , Adulto Jovem
7.
Evolution ; 74(10): 2250-2264, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32786005

RESUMO

Negative interactions between species can generate divergent selection that causes character displacement. However, other processes cause similar divergence. We use spatial and temporal replication across island populations of Anolis lizards to assess the importance of negative interactions in driving trait shifts. Previous work showed that the establishment of Anolis sagrei on islands drove resident Anolis carolinensis to perch higher and evolve larger toepads. To further test the interaction's causality and predictability, we resurveyed a subset of islands nine years later. Anolis sagrei had established on one island between surveys. We found that A. carolinensis on this island now perch higher and have larger toepads. However, toepad morphology change on this island was not distinct from shifts on six other islands whose Anolis community composition had not changed. Thus, the presence of A. sagrei only partly explains A. carolinensis trait variation across space and time. We also found that A. carolinensis on islands with previously established A. sagrei now perch higher than a decade ago, and that current A. carolinensis perch height is correlated with A. sagrei density. Our results suggest that character displacement likely interacts with other evolutionary processes in this system, and that temporal data are key to detecting such interactions.


Assuntos
Comportamento Animal , Evolução Biológica , Comportamento Competitivo , Lagartos/anatomia & histologia , Dedos do Pé/anatomia & histologia , Distribuição Animal , Animais , Ecossistema , Feminino , Florida , Ilhas , Masculino
8.
Transfusion ; 59(7): 2382-2388, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31002398

RESUMO

BACKGROUND: Launched in 2013, Canadian Blood Services' Cord Blood Bank (CBS' CBB) has built a high-quality, ethnically diverse cord blood repository that aims to reduce ethnic disparity in accessing suitable units for transplantation. METHODS AND RESULTS: As of December 2016, 2000 units have been banked. The self-reported maternal ethnicity was 58% non-Caucasian. Overall, 26% of units were classified as multi-ethnicity with Caucasian (84%) most frequently observed in combination with Asian, First Nations (predominant indigenous peoples in Canada south of the Arctic Circle), or African ethnicity. Utilization scores that incorporate total nucleated and CD34+ cell counts in the CBS' CBB were associated with greater likelihood of utilization compared with the international inventory of units (p < 0.05). The distribution of utilization scores was similar for Caucasians compared with non-Caucasians (p < 0.05). Using HLA genotypes of cord blood units and their mothers, we determined probable ethnic assignments for each haplotype using HaploStats (National Marrow Donor Program). Significant increases in HLA-match likelihoods are predicted for all ethnicities as the inventory grows to its target of 10,000 units and the gap in HLA-match likelihoods for Caucasian and non-Caucasian patients progressively declines. CONCLUSIONS: The CBS' CBB inventory is predicted to have high HLA-matching likelihoods across a broad spectrum of ethnic groups, improving access to high-quality stem cell products for all patients.


Assuntos
Bancos de Sangue , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Etnicidade , Sangue Fetal , Teste de Histocompatibilidade , Canadá , Feminino , Humanos , Masculino
9.
Genetica ; 146(6): 443-459, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30244302

RESUMO

Invasive species are a major threat to global biodiversity. The US state of Florida is especially susceptible to the spread of exotic reptiles due to its subtropical climate, disturbed habitats, and robust pet trade. The Argentine black-and-white tegu (Salvator merianae) is a large, omnivorous lizard currently established in two different regions of Southern Florida. These two populations pose potential threats to sensitive ground nesting species such as gopher tortoises, American crocodiles, and migratory birds. At present, the introduction histories of these populations and the degree to which they are connected by gene flow are largely unknown. To address these issues, we genotyped S. merianae from Hillsborough and Miami-Dade Counties at ten microsatellite loci to assess intrapopulation genetic diversity, the degree of gene flow between populations, and compare the plausibilities of several potential introduction scenarios. Our results indicate that both populations have low genetic diversity [mean number of effective alleles across loci in both populations = 2.09 and are highly differentiated from each other (GST = 0.170; G″ST = 0.545)]. In addition, our results suggest that these populations underwent a bottleneck event prior to their divergence. We discuss what our results suggest about the histories of Florida's invasive tegu populations, as well as how they inform ongoing management strategies.


Assuntos
Efeito Fundador , Fluxo Gênico , Espécies Introduzidas , Répteis/genética , Animais , Florida , Polimorfismo Genético
10.
Biol Blood Marrow Transplant ; 24(4): 861-865, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29253552

RESUMO

Zika virus has emerged as a potential threat to the Canadian blood supply system. Stem cell donors within Canadian Blood Services' Cord Blood Bank (CBB) and OneMatch Stem Cell and Marrow Network (OM) now undergo screening measures designed to reduce the risk of Zika virus transmission. The impact these screening measures have on cord blood and unrelated adult stem cell donations is currently unknown. Among 146 donor workups initiated by OM between July 2016 and May 2017, 102 were completed and 44 workups were canceled. There were 17 potential donors (11.6%) with a risk of Zika virus exposure identified by the donor questionnaire (13 completed, 4 canceled workups). None of the workups involved a donor diagnosed with confirmed Zika virus within the past 6 months. Only 1 of the 44 canceled workups (and only 1 of 4 cases with a risk of Zika transmission) was canceled because of the risk of Zika transmission, and a backup donor was selected. Canadian Blood Services' CBB identified 25 of 875 cord blood units (2.9%) from women who donated their infants' cord blood and underwent screening that otherwise met the initial cell number thresholds for banking and had at least 1 risk factor for exposure to Zika virus. No women were diagnosed with Zika virus at any point of their pregnancy. All 25 units were discarded. Unrelated donors at OM have a higher incidence of a risk of exposure to Zika virus compared with cord blood donors. Only rarely did transplant centers cancel donor workups due to potential Zika virus exposure. The impact of screening for Zika virus exposure risk on cord blood banking was minor. Continued vigilance and surveillance is recommended.


Assuntos
Bancos de Sangue , Segurança do Sangue , Sangue Fetal , Inquéritos e Questionários , Doadores não Relacionados , Infecção por Zika virus/prevenção & controle , Zika virus , Adulto , Canadá , Feminino , Humanos , Masculino , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Fatores de Risco , Infecção por Zika virus/transmissão
11.
J Am Osteopath Assoc ; 116(9): 594-8, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27571296

RESUMO

BACKGROUND: The 3-piece inflatable penile prosthesis was introduced in 1973 as a treatment for men with erectile dysfunction. Consisting of 2 corporal cylinders, 1 pump, and a fluid-filled reservoir, the prosthesis is placed by blunt dissection into the retropubic space. The dissection for the reservoir is performed blindly into a space juxtaposed with nerves, vessels, and the bladder. OBJECTIVE: To propose a novel approach for inflatable penile prosthesis reservoir placement involving gentle dilation of the retropubic space using a Foley catheter balloon. METHODS: Patient medical records from 1 surgeon were reviewed. Patients did not have a history of pelvic surgery or prostatectomy. Each implant was approached using a penoscrotal incision, and the retropubic space was dilated with a 30-mL Foley catheter balloon filled to 100-mL capacity before reservoir placement. The postoperative visits were examined for complications, including reservoir infection and herniation. A literature search of penile prosthesis reservoir placement technique and complications (eg, herniation, infection) of reservoir placement was also performed. RESULTS: Fifteen patient records were examined. The reservoir herniation rate was 0% and the infection rate was 7%. The average reservoir herniation rate is reported to be 1% to 3%, and the average infection rate is reported to be 1% to 5%. CONCLUSION: The use of a Foley catheter balloon is a safe, atraumatic, cost-effective, and easily performed method of dilating the retropubic space for subsequent inflatable penile prosthesis reservoir placement.


Assuntos
Dilatação/instrumentação , Disfunção Erétil/cirurgia , Implante Peniano , Prótese de Pênis , Cateterismo Urinário/instrumentação , Cateteres Urinários , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
R Soc Open Sci ; 3(4): 150619, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27152204

RESUMO

Three separate breeding populations of the Nile monitor (Varanus niloticus) have been identified in Florida, USA, located in Cape Coral, West Palm Beach and Homestead Air Reserve Base. This large, predatory lizard could have negative effects on Florida's native wildlife. Here, we infer the source of the introduced populations using genetic and statistical approaches, as well as estimate the potential non-native distribution of V. niloticus in North America. We collected genetic data from 25 Florida individuals as well as utilized genetic datasets from reference individuals spanning the full native distribution throughout sub-Saharan Africa. Using occurrence data from the inferred source population and the full species range, we built ecological niche models (ENMs) and projected them onto North America to determine regions with suitable climate. Our results indicated that the introduced populations resulted from three separate introduction events, and all originated from the southern coastal region of West Africa. The ENM built from the West African source population predicted only the southernmost portions of North America to be suitable. Conversely, the model derived from the full species' range predicted suitable climates across a large portion of the United States. This information can be used to focus management and eradication efforts.

13.
J Hered ; 107(4): 349-62, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26971010

RESUMO

Invasive species are widely recognized as important drivers of the ongoing biodiversity crisis. The US state of Florida is especially susceptible to the proliferation of invasive reptiles, and nonnative lizards currently outnumber native lizard species. At present, there are 3 documented breeding populations of the Nile monitor (Varanus niloticus) in different regions of Southern Florida, and these populations are considered potential dangers to threatened, fossorial endemics, such as burrowing owls, American crocodiles, and gopher tortoises. Nevertheless, at present, both the introduction histories of these populations and the degree to which they are connected by gene flow are not known. To address these issues, we genotyped V. niloticus from Cape Coral, Homestead Air Reserve Base, and West Palm Beach at 17 microsatellite loci and conducted a variety of analyses to assess both intrapopulation genetic diversity, the degree of gene flow between populations, and the most likely introduction scenario. The results of our analyses demonstrate that all 3 populations have limited genetic diversity (mean number of effective alleles across loci in all 3 populations ~ 2.00) and are highly differentiated from one another (G ST = 0.268; G″ST = 0.628). Our results also suggest that these populations resulted from independent introduction events that occurred within the past few decades. Consequently, we advise that wildlife managers focus management efforts on containment of existing populations and intensification of monitoring efforts on potential migration corridors.


Assuntos
Variação Genética , Genética Populacional , Lagartos/genética , Dinâmica Populacional , Animais , Teorema de Bayes , Florida , Fluxo Gênico , Genótipo , Geografia , Desequilíbrio de Ligação , Repetições de Microssatélites , Densidade Demográfica
14.
J Lab Autom ; 21(4): 533-47, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26077162

RESUMO

Disease detection at the molecular level is driving the emerging revolution of early diagnosis and treatment. A challenge facing the field is that protein biomarkers for early diagnosis can be present in very low abundance. The lower limit of detection with conventional immunoassay technology is the upper femtomolar range (10(-13) M). Digital immunoassay technology has improved detection sensitivity three logs, to the attomolar range (10(-16) M). This capability has the potential to open new advances in diagnostics and therapeutics, but such technologies have been relegated to manual procedures that are not well suited for efficient routine use. We describe a new laboratory instrument that provides full automation of single-molecule array (Simoa) technology for digital immunoassays. The instrument is capable of single-molecule sensitivity and multiplexing with short turnaround times and a throughput of 66 samples/h. Singleplex and multiplexed digital immunoassays were developed for 16 proteins of interest in cardiovascular, cancer, infectious disease, neurology, and inflammation research. The average sensitivity improvement of the Simoa immunoassays versus conventional ELISA was >1200-fold, with coefficients of variation of <10%. The potential of digital immunoassays to advance human diagnostics was illustrated in two clinical areas: traumatic brain injury and early detection of infectious disease.


Assuntos
Automação Laboratorial/instrumentação , Automação Laboratorial/métodos , Técnicas de Laboratório Clínico/instrumentação , Técnicas de Laboratório Clínico/métodos , Imunoensaio/instrumentação , Imunoensaio/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador/instrumentação , Fatores de Tempo
15.
J Immunol Methods ; 424: 20-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25960176

RESUMO

We report a system and assay for performing fully-automated measurement of 6 proteins simultaneously with single molecule sensitivity. The system combines handling of samples, reagents, and consumables, with a module for imaging single molecule arrays (Simoa) to enable immunoassays that have high sensitivity (~fg/mL), are multiplexed, and are fully-automated. A 6-plex cytokine Simoa assay for IL-6, TNF-α, GM-CSF, IL-10, IL-1ß, and IL-1α was developed on the system. The assays had limits of detection in the range 0.01-0.03pg/mL, and the average imprecision (CV) of the Simoa signal was 4.2%. This assay was used to measure the concentrations of these cytokines in the plasma of patients with Crohn's Disease (CD), before and after treatment with anti-TNF-α antibody drugs, and in the serum of Type 1 diabetics. Concentrations of TNF-α and IL-6 in the CD samples determined using the fully-automated, multiplex Simoa assay had good correlation with the manual, single-plex assays previously reported. Drug treatment caused reductions in the mean concentration of all 6 cytokines in the plasma of CD patients. The concentrations of 4 cytokines were significantly higher in diabetics compared to healthy controls. The system could enable the widespread, multiplexed measurement of protein biomarkers with low abundance.


Assuntos
Automação , Citocinas/sangue , Imunoensaio/métodos , Doença de Crohn/sangue , Diabetes Mellitus/sangue , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoensaio/instrumentação , Reprodutibilidade dos Testes , Fluxo de Trabalho
16.
Int J Parasitol Parasites Wildl ; 4(3): 379-84, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26759792

RESUMO

Because shifts in host-parasite relationships can alter host populations, attention should be given to the parasites that introduced species take with them or acquire in their introduced range. The Cuban treefrog, Osteopilus septentrionalis, is a successful invasive species in Florida with its parasites in the native range being well-documented, but there is a void in the literature regarding what parasites were lost or introduced in its expansion. We necropsied 330 O. septentrionalis from Tampa, FL and compared their macroparasites to those of O. septentrionalis in their native range and to the parasites of anurans native to the Tampa, FL area to determine the species O. septentrionalis likely introduced or acquired in Florida. At least nine parasite species (Aplectana sp., Oswaldocruzia lenteixeirai, Cylindrotaenia americana, Physaloptera sp., Rhabdias sp., Centrorhynchus sp., unidentified trematode metacercariae, unidentified larval acuariids, and unidentified pentastomids) were isolated. We found no differences in parasite communities of adult male and female frogs, which averaged 19.36 parasite individuals and 1.39 parasite species per adult frog, and had an overall prevalence of 77.52%. Acuariid larvae were likely acquired by O. septentrionalis in FL because they are not found in their native range. O. lenteixeirai was likely introduced because it is commonly reported in O. septentrionalis' native range but has never been reported in FL-native anurans. Aplectana sp. is also likely introduced because it has been reported in several anurans in Cuba but only reported once in Florida. O. septentrionalis tended to harbor fewer of its native parasites in the introduced range, which is consistent with the enemy release hypothesis and potentially creates an immunological advantage for this invasive host. Because native populations can be threatened by introduced parasites, there is a need to further explore the frequency and rate at which non-native hosts introduce parasites.

17.
Proc Natl Acad Sci U S A ; 111(52): 18530-5, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25512489

RESUMO

A seasonally occurring summer hypoxic (low oxygen) zone in the northern Gulf of Mexico is the second largest in the world. Reductions in nutrients from agricultural cropland in its watershed are needed to reduce the hypoxic zone size to the national policy goal of 5,000 km(2) (as a 5-y running average) set by the national Gulf of Mexico Task Force's Action Plan. We develop an integrated assessment model linking the water quality effects of cropland conservation investment decisions on the more than 550 agricultural subwatersheds that deliver nutrients into the Gulf with a hypoxic zone model. We use this integrated assessment model to identify the most cost-effective subwatersheds to target for cropland conservation investments. We consider targeting of the location (which subwatersheds to treat) and the extent of conservation investment to undertake (how much cropland within a subwatershed to treat). We use process models to simulate the dynamics of the effects of cropland conservation investments on nutrient delivery to the Gulf and use an evolutionary algorithm to solve the optimization problem. Model results suggest that by targeting cropland conservation investments to the most cost-effective location and extent of coverage, the Action Plan goal of 5,000 km(2) can be achieved at a cost of $2.7 billion annually. A large set of cost-hypoxia tradeoffs is developed, ranging from the baseline to the nontargeted adoption of the most aggressive cropland conservation investments in all subwatersheds (estimated to reduce the hypoxic zone to less than 3,000 km(2) at a cost of $5.6 billion annually).

18.
Lab Chip ; 13(15): 2902-11, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23719780

RESUMO

We have developed a method that enables the multiplexed detection of proteins based on counting single molecules. Paramagnetic beads were labeled with fluorescent dyes to create optically distinct subpopulations of beads, and antibodies to specific proteins were then immobilized to individual subpopulations. Mixtures of subpopulations of beads were then incubated with a sample, and specific proteins were captured on their specific beads; these proteins were then labeled with enzymes via immunocomplex formation. The beads were suspended in enzyme substrate, loaded into arrays of femtoliter wells--or Single Molecule Arrays (Simoa)--that were integrated into a microfluidic device (the Simoa disc). The wells were then sealed with oil, and imaged fluorescently to determine: a) the location and subpopulation identity of individual beads in the femtoliter wells, and b) the presence or absence of a single enzyme associated with each bead. The images were analyzed to determine the average enzyme per bead (AEB) for each bead subpopulation that provide a quantitative parameter for determining the concentration of each protein. We used this approach to simultaneously detect TNF-α, IL-6, IL-1α, and IL-1ß in human plasma with single molecule resolution at subfemtomolar concentrations, i.e., 200- to 1000-fold more sensitive than current multiplexed immunoassays. The simultaneous, specific, and sensitive measurement of several proteins using multiplexed digital ELISA could enable more reliable diagnoses of disease.


Assuntos
Ensaio de Imunoadsorção Enzimática/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Anticorpos Imobilizados/química , Desenho de Equipamento , Corantes Fluorescentes/química , Humanos , Interleucina-1alfa/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Imagem Óptica , Sensibilidade e Especificidade , Fator de Necrose Tumoral alfa/sangue
19.
J Vis Exp ; (70): e4009, 2012 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-23242132

RESUMO

Finding the cost-efficient (i.e., lowest-cost) ways of targeting conservation practice investments for the achievement of specific water quality goals across the landscape is of primary importance in watershed management. Traditional economics methods of finding the lowest-cost solution in the watershed context (e.g.,(5,12,20)) assume that off-site impacts can be accurately described as a proportion of on-site pollution generated. Such approaches are unlikely to be representative of the actual pollution process in a watershed, where the impacts of polluting sources are often determined by complex biophysical processes. The use of modern physically-based, spatially distributed hydrologic simulation models allows for a greater degree of realism in terms of process representation but requires a development of a simulation-optimization framework where the model becomes an integral part of optimization. Evolutionary algorithms appear to be a particularly useful optimization tool, able to deal with the combinatorial nature of a watershed simulation-optimization problem and allowing the use of the full water quality model. Evolutionary algorithms treat a particular spatial allocation of conservation practices in a watershed as a candidate solution and utilize sets (populations) of candidate solutions iteratively applying stochastic operators of selection, recombination, and mutation to find improvements with respect to the optimization objectives. The optimization objectives in this case are to minimize nonpoint-source pollution in the watershed, simultaneously minimizing the cost of conservation practices. A recent and expanding set of research is attempting to use similar methods and integrates water quality models with broadly defined evolutionary optimization methods(3,4,9,10,13-15,17-19,22,23,25). In this application, we demonstrate a program which follows Rabotyagov et al.'s approach and integrates a modern and commonly used SWAT water quality model(7) with a multiobjective evolutionary algorithm SPEA2(26), and user-specified set of conservation practices and their costs to search for the complete tradeoff frontiers between costs of conservation practices and user-specified water quality objectives. The frontiers quantify the tradeoffs faced by the watershed managers by presenting the full range of costs associated with various water quality improvement goals. The program allows for a selection of watershed configurations achieving specified water quality improvement goals and a production of maps of optimized placement of conservation practices.


Assuntos
Agricultura/métodos , Algoritmos , Conservação dos Recursos Naturais/métodos , Hidrologia/métodos , Modelos Teóricos , Recursos Hídricos , Análise Custo-Benefício , Movimentos da Água
20.
Lab Chip ; 12(5): 977-85, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22179487

RESUMO

We report a method for isolating individual paramagnetic beads in arrays of femtolitre-sized wells and detecting single enzyme-labeled proteins on these beads using sequential fluid flows in microfabricated polymer array assemblies. Arrays of femtolitre-sized wells were fabricated in cyclic olefin polymer (COP) using injection moulding based on DVD manufacturing. These arrays were bonded to a complementary fluidic structure that was also moulded in COP to create an enclosed device to allow delivery of liquids to the arrays. Enzyme-associated, paramagnetic beads suspended in aqueous solutions of enzyme substrate were delivered fluidically to the array such that one bead per well was loaded by gravity. A fluorocarbon oil was then flowed into the device to remove excess beads from the surface of the array, and to seal and isolate the femtolitre-sized wells containing beads and enzyme substrate. The device was then imaged using standard fluorescence imaging to determine which wells contained single enzyme molecules. The analytical performance of this device as the detector for digital ELISA compared favourably to the standard method, i.e., glass arrays mechanically sealed against a silicone gasket; prostate specific antigen (PSA) could be detected from 0.011 pg mL(-1) up to 100 pg mL(-1). The use of an enclosed fluidic device to isolate beads in single-molecule arrays offers a multitude of advantages for low-cost manufacturing, ease of automation, and instrument development to enable applications in biomarker validation and medical diagnosis.


Assuntos
Magnetismo , Nanopartículas/química , Polímeros/química , Cicloparafinas/química , Análise em Microsséries , Antígeno Prostático Específico/química
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