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1.
Proc Natl Acad Sci U S A ; 121(17): e2307220121, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38621138

RESUMEN

The expansion of the oil palm industry in Indonesia has improved livelihoods in rural communities, but comes at the cost of biodiversity and ecosystem degradation. Here, we investigated ways to balance ecological and economic outcomes of oil palm cultivation. We compared a wide range of production systems, including smallholder plantations, industrialized company estates, estates with improved agronomic management, and estates with native tree enrichment. Across all management types, we assessed multiple indicators of biodiversity, ecosystem functions, management, and landscape structure to identify factors that facilitate economic-ecological win-wins, using palm yields as measure of economic performance. Although, we found that yields in industrialized estates were, on average, twice as high as those in smallholder plantations, ecological indicators displayed substantial variability across systems, regardless of yield variations, highlighting potential for economic-ecological win-wins. Reducing management intensity (e.g., mechanical weeding instead of herbicide application) did not lower yields but improved ecological outcomes at moderate costs, making it a potential measure for balancing economic and ecological demands. Additionally, maintaining forest cover in the landscape generally enhanced local biodiversity and ecosystem functioning within plantations. Enriching plantations with native trees is also a promising strategy to increase ecological value without reducing productivity. Overall, we recommend closing yield gaps in smallholder cultivation through careful intensification, whereas conventional plantations could reduce management intensity without sacrificing yield. Our study highlights various pathways to reconcile the economics and ecology of palm oil production and identifies management practices for a more sustainable future of oil palm cultivation.


Asunto(s)
Arecaceae , Aceites Industriales , Ecosistema , Bosques , Biodiversidad , Agricultura , Árboles , Aceite de Palma , Conservación de los Recursos Naturales
2.
Appl Environ Microbiol ; 90(3): e0127823, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38334406

RESUMEN

Clostridioides difficile represents a major burden to public health. As a well-known nosocomial pathogen whose occurrence is highly associated with antibiotic treatment, most examined C. difficile strains originated from clinical specimen and were isolated under selective conditions employing antibiotics. This suggests a significant bias among analyzed C. difficile strains, which impedes a holistic view on this pathogen. In order to support extensive isolation of C. difficile strains from environmental samples, we designed a detection PCR that targets the hpdBCA-operon and thereby identifies low abundances of C. difficile in environmental samples. This operon encodes the 4-hydroxyphenylacetate decarboxylase, which catalyzes the production of the antimicrobial compound para-cresol. Amplicon-based analyses of diverse environmental samples demonstrated that the designed PCR is highly specific for C. difficile and successfully detected C. difficile despite its absence in general 16S rRNA gene-based detection strategies. Further analyses revealed the potential of the hpdBCA detection PCR sequence for initial phylogenetic classification, which allows assessment of C. difficile diversity in environmental samples via amplicon sequencing. Our findings furthermore showed that C. difficile strains isolated under antibiotic treatment from environmental samples were originally dominated by other strains according to PCR amplicon results. This provided evidence for selective cultivation of under-represented but antibiotic-resistant isolates. Thereby, we revealed a substantial bias in C. difficile isolation and research.IMPORTANCEClostridioides difficile is a main cause of diarrheic infections after antibiotic treatment with serious morbidity and mortality worldwide. Research on this pathogen and its virulence has focused on bacterial isolation from clinical specimens under antibiotic treatment, which implies a substantial bias in isolated strains. Comprehensive studies, however, require an unbiased strain collection, which is accomplished by isolation of C. difficile from diverse environmental samples and avoidance of antibiotic-based enrichment strategies. Thus, isolation can significantly benefit from our C. difficile-specific detection PCR, which rapidly verifies C. difficile presence in environmental samples and further allows estimation of the C. difficile diversity by using next-generation sequencing.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , ADN Ambiental , Humanos , Clostridioides , ARN Ribosómico 16S/genética , Filogenia , Antibacterianos/farmacología , Reacción en Cadena de la Polimerasa , Infecciones por Clostridium/microbiología
3.
Nature ; 618(7964): 316-321, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37225981

RESUMEN

In the United Nations Decade on Ecosystem Restoration1, large knowledge gaps persist on how to increase biodiversity and ecosystem functioning in cash crop-dominated tropical landscapes2. Here, we present findings from a large-scale, 5-year ecosystem restoration experiment in an oil palm landscape enriched with 52 tree islands, encompassing assessments of ten indicators of biodiversity and 19 indicators of ecosystem functioning. Overall, indicators of biodiversity and ecosystem functioning, as well as multidiversity and ecosystem multifunctionality, were higher in tree islands compared to conventionally managed oil palm. Larger tree islands led to larger gains in multidiversity through changes in vegetation structure. Furthermore, tree enrichment did not decrease landscape-scale oil palm yield. Our results demonstrate that enriching oil palm-dominated landscapes with tree islands is a promising ecological restoration strategy, yet should not replace the protection of remaining forests.


Asunto(s)
Biodiversidad , Productos Agrícolas , Restauración y Remediación Ambiental , Aceite de Palma , Árboles , Bosques , Aceite de Palma/provisión & distribución , Árboles/fisiología , Agricultura/métodos , Naciones Unidas , Clima Tropical , Productos Agrícolas/provisión & distribución , Restauración y Remediación Ambiental/métodos
4.
Int J Mol Sci ; 22(10)2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-34068175

RESUMEN

Low phosphorus (P) availability is a major limiting factor for potatoes. P fertilizer is applied to enhance P availability; however, it may become toxic when plants accumulate at high concentrations. Therefore, it is necessary to gain more knowledge of the morphological and biochemical processes associated with P deficiency and toxicity for potatoes, as well as to explore an alternative approach to ameliorate the P deficiency condition. A comprehensive study was conducted (I) to assess plant morphology, mineral allocation, and metabolites of potatoes in response to P deficiency and toxicity; and (II) to evaluate the potency of plant growth-promoting rhizobacteria (PGPR) in improving plant biomass, P uptake, and metabolites at low P levels. The results revealed a reduction in plant height and biomass by 60-80% under P deficiency compared to P optimum. P deficiency and toxicity conditions also altered the mineral concentration and allocation in plants due to nutrient imbalance. The stress induced by both P deficiency and toxicity was evident from an accumulation of proline and total free amino acids in young leaves and roots. Furthermore, root metabolite profiling revealed that P deficiency reduced sugars by 50-80% and organic acids by 20-90%, but increased amino acids by 1.5-14.8 times. However, the effect of P toxicity on metabolic changes in roots was less pronounced. Under P deficiency, PGPR significantly improved the root and shoot biomass, total root length, and root surface area by 32-45%. This finding suggests the potency of PGPR inoculation to increase potato plant tolerance under P deficiency.


Asunto(s)
Fósforo/metabolismo , Desarrollo de la Planta , Rhizobiaceae/fisiología , Solanum tuberosum/anatomía & histología , Solanum tuberosum/metabolismo , Estrés Fisiológico , Hojas de la Planta/anatomía & histología , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Raíces de Plantas/anatomía & histología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Solanum tuberosum/crecimiento & desarrollo , Solanum tuberosum/microbiología
5.
Am J Hum Genet ; 99(4): 894-902, 2016 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-27616477

RESUMEN

To safeguard the cell from the accumulation of potentially harmful metabolic intermediates, specific repair mechanisms have evolved. APOA1BP, now renamed NAXE, encodes an epimerase essential in the cellular metabolite repair for NADHX and NADPHX. The enzyme catalyzes the epimerization of NAD(P)HX, thereby avoiding the accumulation of toxic metabolites. The clinical importance of the NAD(P)HX repair system has been unknown. Exome sequencing revealed pathogenic biallelic mutations in NAXE in children from four families with (sub-) acute-onset ataxia, cerebellar edema, spinal myelopathy, and skin lesions. Lactate was elevated in cerebrospinal fluid of all affected individuals. Disease onset was during the second year of life and clinical signs as well as episodes of deterioration were triggered by febrile infections. Disease course was rapidly progressive, leading to coma, global brain atrophy, and finally to death in all affected individuals. NAXE levels were undetectable in fibroblasts from affected individuals of two families. In these fibroblasts we measured highly elevated concentrations of the toxic metabolite cyclic-NADHX, confirming a deficiency of the mitochondrial NAD(P)HX repair system. Finally, NAD or nicotinic acid (vitamin B3) supplementation might have therapeutic implications for this fatal disorder.


Asunto(s)
Proteínas Portadoras/genética , Enfermedades Metabólicas/genética , Mutación , NAD/análogos & derivados , Enfermedades del Sistema Nervioso/genética , Racemasas y Epimerasas/genética , Proteínas Portadoras/metabolismo , Línea Celular , Preescolar , Resultado Fatal , Femenino , Fibroblastos , Humanos , Lactante , Masculino , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/patología , NAD/metabolismo , Enfermedades del Sistema Nervioso/metabolismo , Enfermedades del Sistema Nervioso/patología , Neuroimagen , Anomalías Cutáneas/genética , Anomalías Cutáneas/patología
7.
Lancet Oncol ; 14(9): 843-52, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23823158

RESUMEN

BACKGROUND: Although the survival of children and adolescents with malignant germ-cell tumours has improved greatly in recent years, the outcome remains poor for those with refractory or recurrent malignant germ-cell tumours. We aimed to determine whether objective tumour response could be achieved in patients with refractory or recurrent malignant germ-cell tumours with PEI-regional deep hyperthermia as salvage treatment. METHODS: Patients with refractory or recurrent non-testicular malignant germ-cell tumours after standard cisplatin-based chemotherapy were treated prospectively with PEI chemotherapy (cisplatin 40 mg/m(2), delivered intravenously on days 1 and 4; etoposide 100 mg/m(2), intravenously on days 1-4; and ifosfamide 1800 mg/m(2), intravenously on days 1-4) plus simultaneous 1-h regional deep hyperthermia (41-43°C) on days 1 and 4. Patients received three to four treatment courses at 21-day intervals until residual tumour resection was possible; they subsequently received one or two additional courses of PEI-regional deep hyperthermia. Local radiotherapy was given for incompletely resected tumours. Chemotherapy and hyperthermia toxic effects were assessed using WHO grading. The primary endpoint was the proportion of patients who had an objective response as assessed with Response Evaluation Criteria in Solid Tumors version 1.0 guidelines. Secondary endpoints were the event-free survival and overall survival after 5 years. This ongoing PEI-regional deep hyperthermia study (Hyper-PEI protocol) is registered at the German Cancer Society, number 50-2732. FINDINGS: 44 patients aged 7 months to 21 years (median 2 years 7 months) with refractory or recurrent malignant germ-cell tumours (nine patients with poor response, 23 patients with first relapse, 12 patients with multiple relapses) were included in this study. We identified 34 yolk sac tumours, eight embryonal carcinomas, one choriocarcinoma, and one dysgerminoma by histology analysis. Of the 35 patients who had sufficient clinical and radiographical data available for response assessment, 30 (86%) had an objective response to treatment (16 patients had complete remission and 14 had partial remission). 5-year event-free survival was 62% (95% CI 45-75), and 5-year overall survival was 72% (95% CI 55-83). The median follow-up of surviving patients was 82 months (range 9-195). WHO grade 3-4 neutropenia and thrombocytopenia occurred in all 181 chemotherapy cycles. Granulocytopenic fever, which required intercurrent hospital admission, was noted in 29 (66%) of 44 patients after 53 (29%) of 181 courses. Five patients experienced treatment-related grade-3 acute renal toxic effects. INTERPRETATION: A multimodal strategy integrating PEI-regional deep hyperthermia and tumour resection with or without radiation can successfully treat children and adolescents with refractory or recurrent malignant non-testicular germ-cell tumours. The long-term prognosis of patients with poor response or after first relapse was almost similar to those receiving first-line treatment. This strategy merits further investigation. FUNDING: Deutsche Krebshilfe eV, Bonn, Elterninitiative Kinderkrebsklinik Düsseldorf eV, the Barbara and Hubertus-Trettnerstiftung, and the Marie Quendt Fund.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resistencia a Antineoplásicos , Hipertermia Inducida , Recurrencia Local de Neoplasia/terapia , Neoplasias de Células Germinales y Embrionarias/terapia , Terapia Recuperativa , Adolescente , Adulto , Niño , Preescolar , Cisplatino/administración & dosificación , Terapia Combinada , Etopósido/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Ifosfamida/administración & dosificación , Lactante , Masculino , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Neoplasias de Células Germinales y Embrionarias/mortalidad , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Adulto Joven
8.
J Environ Radioact ; 80(3): 327-39, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15725506

RESUMEN

A project to characterize the radionuclide and chemical components in natural spring waters in the vicinity of Saratoga Springs, New York (USA) has been completed. As a result of the measured radionuclide and chemical content, eight springs were labeled as mineral waters, whereas three springs contained very low concentrations of these components. The mineral waters were highly enriched in alkaline and alkaline-earth elements, as well as chloride ions. Three isotopes of radium ((224)Ra, (226)Ra, (228)Ra) were detected in the mineral waters and reached concentrations of 1, 20, and 2 Bq/L, respectively. Overall, the (226)Ra isotope constituted about 80% of the total radioactivity measured in the water samples. Dissolved uranium concentrations in the mineral waters were very low (mean approximately 50 mBq/L).


Asunto(s)
Radón/análisis , Uranio/análisis , Abastecimiento de Agua/normas , Agua/química , Monitoreo del Ambiente , Concentración de Iones de Hidrógeno , New York
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