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1.
Transfusion ; 64 Suppl 2: S27-S33, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38251751

RESUMO

BACKGROUND: Whole blood (WB) collections can occur downrange for immediate administration. An important aspect of these collections is determining when the unit is sufficiently full. This project tested a novel method for determining when a field collection is complete. METHODS: The amount of empty space at the top of WB units, destined to become LTOWB or separated into components, that were collected at blood centers or hospitals was measured by holding a WB unit off the ground and placing the top of a piece of string where the donor tubing entered the bag. The string was marked where it intersected the top of the column of blood in the bag and measured from the top. The WB units were also weighed. RESULTS: A total of 15 different bags, two of which were measured in two different filling volumes, from 15 hospitals or blood centers were measured and weighed. The most commonly used blood bag, Terumo Imuflex SP, had a median string length of 9 mm (range: 2-24 mm) and weighed a median of 565.1 g (range: 524.8-636.7 g). CONCLUSION: Pieces of string can be precut to the appropriate length depending on the type of bag before a mission where field WB collections might be required and a mark placed on the bag before the collection commences to indicate when the unit is full.


Assuntos
Doadores de Sangue , Humanos , Bancos de Sangue , Coleta de Amostras Sanguíneas/métodos , Coleta de Amostras Sanguíneas/instrumentação
2.
Eur J Haematol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989562

RESUMO

BACKGROUND: 6-mercaptopurine is a cornerstone of maintenance therapy for pediatric ALL. Response to 6MP is typically determined by the ANC. Therapeutic ANC range while receiving 6MP is between 500 and 1500/µL. In addition to desired myelosuppression, 6MP is associated with multiple adverse drug effects. Increased doses of 6MP can lead to therapeutic ANC values; however, patients may experience adverse effects before obtaining therapeutic myelosuppression, often deemed "skewed metabolism." Allopurinol may potentially correct skewed 6MP metabolism. PROCEDURE: Pediatric patients with ALL with 6MMP and 6TGN metabolites drawn during maintenance therapy were analyzed for allopurinol use. The primary outcome evaluated the percentage of time spent in therapeutic ANC range before and after allopurinol initiation. In addition, the difference in 6MMP:6TGN ratios before and after allopurinol initiation, incidence of hepatotoxicity, and rates of relapse, were analyzed. RESULTS: Ninety-five patients were included for analysis. Thirty-two (34%) patients received allopurinol. There were no significant differences in baseline demographics between the patients who received allopurinol and those who did not. When comparing ANC values pre- and post-allopurinol initiation, a statistically significant increase in the percentage of time spent in therapeutic range was observed (27% vs. 43%; p = .03). In addition, when comparing metabolite ratios pre- and post-allopurinol initiation, a statistically significant decrease in 6MMP:6TGN metabolite ratio values was observed (86.7 vs. 3.6; p < .0001). CONCLUSIONS: Allopurinol significantly increased the percent time in therapeutic ANC range and can be safely utilized to significantly lower the ratio of 6MMP:6TGN metabolites, alleviating the undesirable side effects of 6MMP, and optimizing the anti-leukemic effects associated with 6TGN.

3.
J Immunol ; 209(9): 1674-1690, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36150727

RESUMO

Immunomodulatory (IM) metabolic reprogramming in macrophages (Mϕs) is fundamental to immune function. However, limited information is available for human Mϕs, particularly in response plasticity, which is critical to understanding the variable efficacy of immunotherapies in cancer patients. We carried out an in-depth analysis by combining multiplex stable isotope-resolved metabolomics with reversed phase protein array to map the dynamic changes of the IM metabolic network and key protein regulators in four human donors' Mϕs in response to differential polarization and M1 repolarizer ß-glucan (whole glucan particles [WGPs]). These responses were compared with those of WGP-treated ex vivo organotypic tissue cultures (OTCs) of human non-small cell lung cancer. We found consistently enhanced tryptophan catabolism with blocked NAD+ and UTP synthesis in M1-type Mϕs (M1-Mϕs), which was associated with immune activation evidenced by increased release of IL-1ß/CXCL10/IFN-γ/TNF-α and reduced phagocytosis. In M2a-Mϕs, WGP treatment of M2a-Mϕs robustly increased glucose utilization via the glycolysis/oxidative branch of the pentose phosphate pathway while enhancing UDP-N-acetyl-glucosamine turnover and glutamine-fueled gluconeogenesis, which was accompanied by the release of proinflammatory IL-1ß/TNF-α to above M1-Mϕ's levels, anti-inflammatory IL-10 to above M2a-Mϕ's levels, and attenuated phagocytosis. These IM metabolic responses could underlie the opposing effects of WGP, i.e., reverting M2- to M1-type immune functions but also boosting anti-inflammation. Variable reprogrammed Krebs cycle and glutamine-fueled synthesis of UTP in WGP-treated OTCs of human non-small cell lung cancer were observed, reflecting variable M1 repolarization of tumor-associated Mϕs. This was supported by correlation with IL-1ß/TNF-α release and compromised tumor status, making patient-derived OTCs unique models for studying variable immunotherapeutic efficacy in cancer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , beta-Glucanas , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Glucosamina/metabolismo , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Interleucina-10 , Neoplasias Pulmonares/metabolismo , Macrófagos , NAD/metabolismo , Fagocitose , Triptofano/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Difosfato de Uridina/metabolismo , Uridina Trifosfato/metabolismo , beta-Glucanas/metabolismo
4.
Transfusion ; 63 Suppl 3: S222-S229, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37042672

RESUMO

INTRODUCTION: Limb and junctional hemorrhage are leading causes of potentially preventable death among trauma casualties. Hemorrhage control for these regions could be achieved by direct or indirect pressure. The manual pressure points (MPP) involves applying manual pressure on the arterial supply to occlude distal blood flow without the need for specialized equipment. STUDY DESIGN AND METHODS: Prospective, non-randomized, human volunteer, controlled environment study involving 38 healthy military caregivers, with 26 participants attending a short instructional session. During a medical exercise, participants were requested to apply pressure on the supraclavicular and femoral points aiming to stop regional blood flow, measured by distal pulse palpation. The measures recorded included achievement of distal pulse cessation, success in achieving cessation for a full minute, and subjects' pain scores reported after each attempt. RESULTS: All participants succeeded in achieving distal pulse cessation for both the supraclavicular and femoral points for a full minute. The median time to initial success was 3.0 (interquartile range 2.0-5.0) seconds in the supraclavicular point and 4.5 (interquartile range 3.0-6.0) seconds in the femoral point. Pain scores ranging between 0 and 3 were reported by most subjects during supraclavicular (68.4%) and femoral occlusion (84.2%). CONCLUSION: The MPP technique was highly effective in occluding distal palpable pulses in healthy volunteers when applied to the supraclavicular and femoral arteries. Brief instruction on the technique can potentially improve the chances of achieving hemorrhage control within 5 s. Further research is required to determine efficacy among different populations and providers with varying experience levels.


Assuntos
Hemodinâmica , Hemorragia , Humanos , Estudos Prospectivos , Hemorragia/etiologia , Artéria Femoral/lesões , Dor
5.
Pediatr Blood Cancer ; 70(7): e30365, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37073741

RESUMO

BACKGROUND: Survival for children with metastatic hepatoblastoma (HB) remains suboptimal. We report the response rate and outcome of two courses of vincristine/irinotecan/temsirolimus (VIT) in children with high-risk (HR)/metastatic HB. PROCEDURES: Patients with newly diagnosed HB received HR window chemotherapy if they had metastatic disease or a serum alpha-fetoprotein (AFP) level less than 100 ng/mL. Patients received vincristine (days 1 and 8), irinotecan (days 1-5), and temsirolimus (days 1 and 8). Cycles were repeated every 21 days. Responders had either a 30% decrease using RECIST (Response Evaluation Criteria in Solid Tumors) criteria OR a 90% (>1 log10 decline) AFP decline after two cycles. Responders received two additional cycles of VIT intermixed with six cycles of cisplatin/doxorubicin/5-fluorouracil/vincristine (C5VD). Nonresponders received six cycles of C5VD alone. RESULTS: Thirty-six eligible patients enrolled on study. The median age at enrollment was 27 months (range: 7-170). Seventeen of 36 patients were responders (RECIST and AFP = 3, RECIST only = 4, AFP only = 10). The median AFP at diagnosis was 222,648 ng/mL and the median AFP following two VIT cycles was 19,262 ng/mL. Three-year event-free survival was 47% (95% confidence interval [CI]: 30%-62%), while overall survival was 67% (95% CI: 49%-80%). CONCLUSION: VIT did not achieve the study efficacy endpoint. Temsirolimus does not improve the response rate seen in patients treated with vincristine and irinotecan (VI) alone as part of the initial treatment regimen explored in this study. Additionally, AFP response may be a more sensitive predictor of disease response than RECIST in HB.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Criança , Humanos , Hepatoblastoma/patologia , Irinotecano/uso terapêutico , Vincristina , Neoplasias Hepáticas/patologia , alfa-Fetoproteínas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resultado do Tratamento
6.
Nature ; 546(7656): 65-72, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569811

RESUMO

Biodiversity enhances many of nature's benefits to people, including the regulation of climate and the production of wood in forests, livestock forage in grasslands and fish in aquatic ecosystems. Yet people are now driving the sixth mass extinction event in Earth's history. Human dependence and influence on biodiversity have mainly been studied separately and at contrasting scales of space and time, but new multiscale knowledge is beginning to link these relationships. Biodiversity loss substantially diminishes several ecosystem services by altering ecosystem functioning and stability, especially at the large temporal and spatial scales that are most relevant for policy and conservation.


Assuntos
Biodiversidade , Atividades Humanas , Animais , Conservação dos Recursos Naturais , Política Ambiental , Extinção Biológica , Análise Espaço-Temporal , Especificidade da Espécie
7.
J Pediatr Hematol Oncol ; 45(7): e921-e923, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37526359

RESUMO

BACKGROUND: Infantile myofibromatosis (IM) is a rare benign tumor of infancy. Cases with solitary and multicentric disease usually spontaneously regress, but multicentric disease with visceral involvement carries a poor prognosis. Few cases of multicentric disease with central nervous system (CNS) involvement have been reported, and none report survival. OBSERVATIONS: We present a newborn with multicentric IM with cutaneous, visceral, and CNS involvement. She was treated with vinblastine, methotrexate, and the novel addition of intrathecal methotrexate with treatment response after 1 year of therapy. CONCLUSIONS: Multicentric IM with CNS involvement can be successfully treated with a multimodal approach of chemotherapy with the addition of intrathecal methotrexate and surgery.


Assuntos
Metotrexato , Miofibromatose , Recém-Nascido , Feminino , Humanos , Metotrexato/uso terapêutico , Miofibromatose/terapia , Miofibromatose/patologia , Vimblastina/uso terapêutico
8.
Vascular ; 31(2): 234-243, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34963378

RESUMO

OBJECTIVE: Practice patterns and durability of parallel stent graft techniques in complex endovascular aneurysm repair (EVAR) remain poorly defined. We aimed to quantify and compare the impact of renal chimney intra-aortic stent length (IASL) on geometric deformations of renal arteries in complex EVAR. METHODS: Thirty-eight nonconsecutive patients underwent EVAR utilizing parallel stent graft techniques (chimney EVAR [chEVAR], n = 28; chimney endovascular aneurysm sealing [chEVAS], n = 10) between 2010 and 2016. A total of 59 renal chimney stent grafts were used. Geometric quantification was derived from three-dimensional model-based centerline extraction. Renal chimney intra-aortic stent length (IASL) was defined as the length of chimney stent that extended from the proximal edge of the chimney stent to the ostium of the corresponding renal artery. RESULTS: Mean IASL for both left and right renal arteries in the cohort was 35.7 mm. Renal arteries containing chimney IASL <30 mm trended toward a greater branch angle (135.4 vs. 127.8°, p = .06). Left renal arteries showed significantly greater branch angle among those with IASL <40 mm (135.5 vs. 121.7°, p = .045). Mean IASL for renal arteries in chEVAR was significantly longer compared to chEVAS (39.2 vs. 26.3 mm, p = .003). No difference was noted in overall branch angle or end-stent angle based on procedure type. ChEVAR with IASL <30 mm had significantly greater end-stent angle (48.2 vs. 33.5°, p = .03). In contrast, chEVAS patients showed no difference in end-stent angle based on IASL thresholds, but did have significantly greater branch angle among those with IASL <30 mm when grouped by both all renal arteries (133.5 vs. 113.5°, p = .004) and right renal arteries (134.3 vs. 111.6°, p = .02). CONCLUSIONS: Renal chimney stents with longer IASL appear to exhibit less renal artery deformation, suggesting a more gradual and perpendicular transition of the chimney stent across the renal ostium.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/métodos , Correção Endovascular de Aneurisma , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Resultado do Tratamento , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Aortografia/métodos , Stents , Desenho de Prótese
9.
Int J Mol Sci ; 24(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37834060

RESUMO

GM2 gangliosidoses are a group of neurodegenerative lysosomal storage disorders that are characterized by the accumulation of GM2 gangliosides (GM2), leading to rapid neurological decline and death. The hydrolysis of GM2 requires the specific synthesis, processing, and combination of products of three genes-HEXA, HEXB, and GM2A-within the cell's lysosomes. Mutations in these genes result in Tay-Sachs disease, Sandhoff disease, or AB-variant GM2 gangliosidosis (ABGM2), respectively. ABGM2, the rarest of the three types, is characterized by a mutation in the GM2A gene, which encodes the GM2 activator (GM2A) protein. Being a monogenic disease, gene therapy is a plausible and likely effective method of treatment for ABGM2. This study aimed at assessing the effects of administering a one-time intravenous treatment of single-stranded Adeno-associated virus serotype 9 (ssAAV9)-GM2A viral vector at a dose of 1 × 1014 vector genomes (vg) per kilogram per mouse in an ABGM2 mouse model (Gm2a-/-). ssAAV9-GM2A was administered at 1-day (neonatal) or 6-weeks of age (adult-stage). The results demonstrated that, in comparison to Gm2a-/- mice that received a vehicle injection, the treated mice had reduced GM2 accumulation within the central nervous system and had long-term persistence of vector genomes in the brain and liver. This proof-of-concept study is a step forward towards the development of a clinically therapeutic approach for the treatment of patients with ABGM2.


Assuntos
Gangliosidoses GM2 , Doença de Tay-Sachs , Humanos , Animais , Camundongos , Dependovirus/genética , Sorogrupo , Doença de Tay-Sachs/terapia , Gangliosidoses GM2/genética , Gangliosidoses GM2/terapia , Proteína Ativadora de G(M2)/genética , Terapia Genética
10.
Cancer ; 128(5): 1057-1065, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34762296

RESUMO

BACKGROUND: The Children's Oncology Group (COG) adopted cisplatin, 5-flourouracil, and vincristine (C5V) as standard therapy after the INT-0098 legacy study showed statistically equivalent survival but less toxicity in comparison with cisplatin and doxorubicin. Subsequent experience demonstrated doxorubicin to be effective in patients with recurrent disease after C5V, and this suggested that it could be incorporated to intensify therapy for patients with advanced disease. METHODS: In this nonrandomized, phase 3 COG trial, the primary aim was to explore the feasibility and toxicity of a novel therapeutic cisplatin, 5-flourouracil, vincristine, and doxorubicin (C5VD) regimen with the addition of doxorubicin to C5V for patients considered to be at intermediate risk. Patients were eligible if they had unresectable, nonmetastatic disease. Patients with a complete resection at diagnosis and local pathologic evidence of small cell undifferentiated histology were also eligible for an assessment of feasibility. RESULTS: One hundred two evaluable patients enrolled between September 14, 2009, and March 12, 2012. Delivery of C5VD was feasible and tolerable: the mean percentages of the target doses delivered were 96% (95% CI, 94%-97%) for cisplatin, 96% (95% CI, 94%-97%) for 5-fluorouracil, 95% (95% CI, 93%-97%) for doxorubicin, and 90% (95% CI, 87%-93%) for vincristine. Toxicity was within expectations, with death as a first event in 1 patient. The most common adverse events were febrile neutropenia (n = 55 [54%]), infection (n = 48 [47%]), mucositis (n = 31 [30%]), hypokalemia (n = 39 [38%]), and elevated aspartate aminotransferase (n = 28 [27%]). The 5-year event-free and overall survival rates for the 93 patients who did not have complete resection at diagnosis were 88% (95% CI, 79%-93%) and 95% (95% CI, 87%-98%), respectively. CONCLUSIONS: The addition of doxorubicin to the previous standard regimen of C5V is feasible, tolerable, and efficacious, and this suggests that C5VD is a good regimen for future clinical trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Hepatoblastoma , Neoplasias Hepáticas , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/efeitos adversos , Doxorrubicina/efeitos adversos , Estudos de Viabilidade , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Vincristina/efeitos adversos
11.
Transfusion ; 62 Suppl 1: S122-S129, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35733031

RESUMO

BACKGROUND: Based on previous experiments in nonhuman primates, we hypothesized that DO2 crit in humans is 5-6 ml O2 ·kg-1  min-1 . STUDY DESIGN AND METHODS: We measured the compensatory reserve (CRM) and calculated oxygen delivery (DO2 ) in 166 healthy, normotensive, nonsmoking subjects (97 males, 69 females) during progressive central hypovolemia induced by lower body negative pressure as a model of ongoing hemorrhage. Subjects were classified as having either high tolerance (HT; N = 111) or low tolerance (LT; N = 55) to central hypovolemia. RESULTS: HT and LT groups were matched for age, weight, BMI, and vital signs, DO2 and CRM at baseline. The CRM-DO2 relationship was best fitted to a logarithmic model in HT subjects (amalgamated R2  = 0.971) and a second-order polynomial model in the LT group (amalgamated R2  = 0.991). Average DO2 crit for the entire subject cohort was estimated at 5.3 ml O2 ·kg-1  min-1 , but was ~14% lower in HT compared with LT subjects. The reduction in DO2 from 40% CRM to 20% CRM was 2-fold greater in the LT compared with the HT group. CONCLUSIONS: Average DO2 crit in humans is 5.3 ml O2 ·kg-1  min-1 , but is ~14% lower in HT compared with LT subjects. The CRM-DO2 relationship is curvilinear in humans, and different when comparing HT and LT individuals. The threshold for an emergent monitoring signal should be recalibrated from 30% to 40% CRM given that the decline in DO2 from 40% CRM to 20% CRM for LT subjects is located on the steepest part of the CRM-DO2 relationship.


Assuntos
Hipovolemia , Pressão Negativa da Região Corporal Inferior , Animais , Pressão Sanguínea , Feminino , Hemodinâmica , Hemorragia , Humanos , Masculino , Oxigênio , Consumo de Oxigênio , Sinais Vitais
12.
J Pediatr Hematol Oncol ; 44(7): 398-401, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35180762

RESUMO

6-mercaptopurine is a mainstay of acute lymphoblastic leukemia treatment. It has a narrow therapeutic window, dictated by its metabolite, thioguanine and 6-methylmercaptopurine. Skin manifestations usually consist of mild facial rash or hypersensitivity exanthems. We report a child who developed a painful acral rash and mucositis while undergoing maintenance therapy for B-cell acute lymphoblastic leukemia without infectious or known drug etiology. Thiopurine metabolites were skewed toward 6-methylmercaptopurine. Two weeks after allopurinol was added and 6-mercaptopurine (6-MP) dose adjusted, the cutaneous manifestations and other constitutional symptoms resolved. We posit that the rash was because of 6-MP toxicity related to skewed metabolism, adding to the growing list of toxicity related to altered 6-MP metabolism.


Assuntos
Linfoma de Burkitt , Exantema , Leucemia-Linfoma Linfoblástico de Células Precursoras , Alopurinol/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Criança , Exantema/induzido quimicamente , Humanos , Mercaptopurina/análogos & derivados , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Tioguanina/metabolismo , Tioguanina/uso terapêutico
13.
Proc Natl Acad Sci U S A ; 116(42): 21061-21067, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31570612

RESUMO

Dispersal and adaptation both allow species to persist in changing environments. Yet, we have limited understanding of how these processes interact to affect species persistence, especially in diverse communities where biotic interactions greatly complicate responses to environmental change. Here we use a stochastic metacommunity model to demonstrate how dispersal and adaptation to environmental change independently and interactively contribute to biodiversity maintenance. Dispersal provides spatial insurance, whereby species persist on the landscape by shifting their distributions to track favorable conditions. In contrast, adaptation allows species to persist by allowing for evolutionary rescue. But, when species both adapt and disperse, dispersal and adaptation do not combine positively to affect biodiversity maintenance, even if they do increase the persistence of individual species. This occurs because faster adapting species evolve to hold onto their initial ranges (i.e., monopolization effects), thus impeding slower adapting species from shifting their ranges and thereby causing extinctions. Importantly, these differences in adaptation speed emerge as the result of competition, which alters population sizes and colonization success. By demonstrating how dispersal and adaptation each independently and interactively contribute to the maintenance of biodiversity, we provide a framework that links the theories of spatial insurance, evolutionary rescue, and monopolization. This highlights the expectation that the maintenance of biodiversity in changing environments depends jointly on rates of dispersal and adaptation, and, critically, the interaction between these processes.


Assuntos
Adaptação Fisiológica/fisiologia , Biodiversidade , Evolução Biológica , Ecossistema , Modelos Biológicos
14.
Am Nat ; 198(6): 694-705, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34762574

RESUMO

AbstractPredicting how ecological communities will respond to environmental change is challenging but highly relevant in this era of global change. Ecologists commonly use current spatial relationships between species and environmental conditions to make predictions about the future. This assumes that species will track conditions by shifting their distributions. However, theory and experimental evidence suggest that species interactions prevent communities from predictably tracking temporal changes in environmental conditions on the basis of current spatial relationships between species and environmental gradients. We tested this hypothesis by assessing the dynamics of protist species in replicated two-patch microcosm landscapes that experienced different regimes of spatial and temporal environmental heterogeneity (light vs. dark). Populations were kept in monocultures or polycultures to assess the effect of species interactions. In monocultures, abundances were predictable on the basis of current environmental conditions, regardless of whether the populations had experienced temporal environmental change. But in polycultures, abundances also depended on the history of the environmental conditions experienced. This suggests that because of species interactions, communities should respond differently to spatial versus temporal environmental changes. Thus, species interactions likely reduce the accuracy of predictions about future communities that are based on current spatial relationships between species and the environment.


Assuntos
Biota , Ecossistema
15.
Proc Biol Sci ; 288(1946): 20202779, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33715425

RESUMO

The biodiversity and ecosystem functioning (BEF) relationship is expected to be scale-dependent. The autocorrelation of environmental heterogeneity is hypothesized to explain this scale dependence because it influences how quickly biodiversity accumulates over space or time. However, this link has yet to be demonstrated in a formal model. Here, we use a Lotka-Volterra competition model to simulate community dynamics when environmental conditions vary across either space or time. Species differ in their optimal environmental conditions, which results in turnover in community composition. We vary biodiversity by modelling communities with different sized regional species pools and ask how the amount of biomass per unit area depends on the number of species present, and the spatial or temporal scale at which it is measured. We find that more biodiversity is required to maintain functioning at larger temporal and spatial scales. The number of species required increases quickly when environmental autocorrelation is low, and slowly when autocorrelation is high. Both spatial and temporal environmental heterogeneity lead to scale dependence in BEF, but autocorrelation has larger impacts when environmental change is temporal. These findings show how the biodiversity required to maintain functioning is expected to increase over space and time.


Assuntos
Biodiversidade , Ecossistema , Biomassa
16.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201771

RESUMO

GM2 gangliosidosis disorders are a group of neurodegenerative diseases that result from a functional deficiency of the enzyme ß-hexosaminidase A (HexA). HexA consists of an α- and ß-subunit; a deficiency in either subunit results in Tay-Sachs Disease (TSD) or Sandhoff Disease (SD), respectively. Viral vector gene transfer is viewed as a potential method of treating these diseases. A recently constructed isoenzyme to HexA, called HexM, has the ability to effectively catabolize GM2 gangliosides in vivo. Previous gene transfer studies have revealed that the scAAV9-HEXM treatment can improve survival in the murine SD model. However, it is speculated that this treatment could elicit an immune response to the carrier capsid and "non-self"-expressed transgene. This study was designed to assess the immunocompetence of TSD and SD mice, and test the immune response to the scAAV9-HEXM gene transfer. HexM vector-treated mice developed a significant anti-HexM T cell response and antibody response. This study confirms that TSD and SD mouse models are immunocompetent, and that gene transfer expression can create an immune response in these mice. These mouse models could be utilized for investigating methods of mitigating immune responses to gene transfer-expressed "non-self" proteins, and potentially improve treatment efficacy.


Assuntos
Dependovirus/genética , Gangliosídeo G(M2)/metabolismo , Vetores Genéticos/administração & dosagem , Imunidade/imunologia , Doença de Sandhoff/imunologia , Doença de Tay-Sachs/imunologia , Cadeia alfa da beta-Hexosaminidase/genética , Animais , Modelos Animais de Doenças , Feminino , Terapia Genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Doença de Sandhoff/genética , Doença de Sandhoff/terapia , Doença de Tay-Sachs/genética , Doença de Tay-Sachs/terapia
17.
J Aquat Anim Health ; 33(1): 33-43, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33098130

RESUMO

Russian Sturgeon Acipenser gueldenstaedtii are an important, critically endangered, roe-producing species. Despite a wealth of knowledge pertaining to other members of family Acipenseridae, there is very limited published information regarding baseline blood analytes in Russian Sturgeon. The objectives of this study were (1) to establish reference intervals for a suite of hematological and biochemical data and (2) to compare plasma chemistry data to two point-of-care (POC) cartridges, tested on the VetScan iSTAT 1 analyzer, that use heparinized whole blood for the assessment of clinically normal, aquacultured adult Russian Sturgeon sedated with eugenol (AQUI-S 20E) at a single institution. Reference intervals are reported. The calculated hematocrit measured by the POC analyzer tended 4-5% lower than the spun packed cell volume, confirming the importance of spun packed cell volume as a reliable measurement of red blood cell mass. Various analytes, notably whole-blood urea nitrogen, glucose, sodium, total carbon dioxide, chloride, ionized calcium, and anion gap, were significantly different by both POC cartridges. This study successfully produced reference intervals for blood analytes in adult Russian Sturgeon under managed care and creates a foundation for future studies into the effects of extrinsic and intrinsic factors and variations of analytical methodologies on blood analytes in this species.


Assuntos
Análise Química do Sangue/veterinária , Peixes , Testes Hematológicos/veterinária , Plasma/química , Animais , Animais de Zoológico , Feminino , Masculino , Valores de Referência
18.
Ecol Lett ; 23(9): 1314-1329, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32672410

RESUMO

The metacommunity concept has the potential to integrate local and regional dynamics within a general community ecology framework. To this end, the concept must move beyond the discrete archetypes that have largely defined it (e.g. neutral vs. species sorting) and better incorporate local scale species interactions and coexistence mechanisms. Here, we present a fundamental reconception of the framework that explicitly links local coexistence theory to the spatial processes inherent to metacommunity theory, allowing for a continuous range of competitive community dynamics. These dynamics emerge from the three underlying processes that shape ecological communities: (1) density-independent responses to abiotic conditions, (2) density-dependent biotic interactions and (3) dispersal. Stochasticity is incorporated in the demographic realisation of each of these processes. We formalise this framework using a simulation model that explores a wide range of competitive metacommunity dynamics by varying the strength of the underlying processes. Using this model and framework, we show how existing theories, including the traditional metacommunity archetypes, are linked by this common set of processes. We then use the model to generate new hypotheses about how the three processes combine to interactively shape diversity, functioning and stability within metacommunities.


Assuntos
Ecossistema , Modelos Biológicos , Biota , Ecologia , Dinâmica Populacional
19.
Ecol Lett ; 23(4): 757-776, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31997566

RESUMO

A rich body of knowledge links biodiversity to ecosystem functioning (BEF), but it is primarily focused on small scales. We review the current theory and identify six expectations for scale dependence in the BEF relationship: (1) a nonlinear change in the slope of the BEF relationship with spatial scale; (2) a scale-dependent relationship between ecosystem stability and spatial extent; (3) coexistence within and among sites will result in a positive BEF relationship at larger scales; (4) temporal autocorrelation in environmental variability affects species turnover and thus the change in BEF slope with scale; (5) connectivity in metacommunities generates nonlinear BEF and stability relationships by affecting population  synchrony at local and regional scales; (6) spatial scaling in food web structure and diversity will generate scale dependence in ecosystem functioning. We suggest directions for synthesis that combine approaches in metaecosystem and metacommunity ecology and integrate cross-scale feedbacks. Tests of this theory may combine remote sensing with a generation of networked experiments that assess effects at multiple scales. We also show how anthropogenic land cover change may alter the scaling of the BEF relationship. New research on the role of scale in BEF will guide policy linking the goals of managing biodiversity and ecosystems.


Assuntos
Biodiversidade , Ecossistema , Ecologia , Cadeia Alimentar
20.
J Gen Virol ; 101(7): 735-745, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32421489

RESUMO

Over the last decade, a number of USA aquaculture facilities have experienced periodic mortality events of unknown aetiology in their clownfish (Amphiprion ocellaris). Clinical signs of affected individuals included lethargy, altered body coloration, reduced body condition, tachypnea, and abnormal positioning in the water column. Samples from outbreaks were processed for routine parasitological, bacteriological, and virological diagnostic testing, but no consistent parasitic or bacterial infections were observed. Histopathological evaluation revealed individual cell necrosis and mononuclear cell inflammation in the branchial cavity, pharynx, oesophagus and/or stomach of four examined clownfish, and large basophilic inclusions within the pharyngeal mucosal epithelium of one fish. Homogenates from pooled external and internal tissues from these outbreaks were inoculated onto striped snakehead (SSN-1) cells for virus isolation and cytopathic effects were observed, resulting in monolayer lysis in the initial inoculation and upon repassage. Transmission electron microscopy of infected SSN-1 cells revealed small round particles (mean diameter=20.0-21.7 nm) within the cytoplasm, consistent with the ultrastructure of a picornavirus. Full-genome sequencing of the purified virus revealed a novel picornavirus most closely related to the bluegill picornavirus and other members of the genus Limnipivirus. Additionally, pairwise protein alignments between the clownfish picornavirus (CFPV) and other known members of the genus Limnipivirus yielded results in accordance with the current International Committee on Taxonomy of Viruses criteria for members of the same genus. Thus, CFPV represents a proposed new limnipivirus species. Future experimental challenge studies are needed to determine the role of CFPV in disease.


Assuntos
Doenças dos Peixes/virologia , Infecções por Picornaviridae/veterinária , Picornaviridae/classificação , Picornaviridae/genética , Animais , Biópsia , Linhagem Celular , Coinfecção , Doenças dos Peixes/diagnóstico , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Picornaviridae/isolamento & purificação
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