Author Correction: Identifying long-term stable refugia for relict plant species in East Asia.

In the original version of this Article, an incorrect sample size was provided for the number of relict species (443 instead of 442) and the number of relict forests (423 instead of 422). These errors have been corrected in both the PDF and HTML versions of the Article.

Identifying long-term stable refugia for relict plant species in East Asia.

Today East Asia harbors many "relict" plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions. We further use Ecological Niche Modeling to show that these patterns align with maps of climate refugia, and we predict species' chances of persistence given the future climatic changes expected for East Asia. By 2070, potentially suitable areas with high richness of relict species will decrease, although the areas as a whole will probably expand. We identify areas in southwestern China and northern Vietnam as long-term climatically stable refugia likely to preserve ancient lineages, highlighting areas that could be prioritized for conservation of such species.

Semi-rational screening of the inhibitors and ß-lactam antibiotics against the New Delhi metallo-ß-lactamase 1 (NDM-1) producing E. coli.

Bacteria containing bla NDM-1 gene are a growing threat to almost all clinically ß-lactam antibiotics. Especially, the New Delhi metallo-ß-lactamase (NDM-1) has become a potential public survival risk. In this study, a novel and efficient strategy for inhibitors and ß-lactam antibiotics screening using recombinant New Delhi metallo-beta-lactamase (NDM-1) was developed. First, the gene of bla NDM-1 were identified and cloned from multi-drug resistance of Acinetobacter baumannii isolate; by the means of protein expression and purification, recombinant NDM-1 activity was up to 68.5 U ml-1, and high purity NDM-1 protein with activity of 347.4 U mg-1 was obtained. Finally, for NDM-1, the inhibitors (aspergillomarasmine A (AMA) and EDTA) with high affinity (HI) and the ß-lactam antibiotics (imipenem) with low affinity (LA) were screened out. Surprisingly, the inhibition of the NDM-1 was enhanced by the use of inhibitor combinations (AMA-EDTA (1 : 2)), where the IC50 of AMA-EDTA was reduced by 88% and 95%, respectively, comparing to the AMA and EDTA alone. More interesting, AMA-EDTA could restore the activity of imipenem when tested against NDM-1 expressing strains (E. coli and Acinetobacter baumannii), with a working time of 120 min and 330 min, respectively. This method is expected to be used in high-throughput screening, drug redesign (including new inhibitors and drugs) and "old drug new use".

Factores de riesgo de las infecciones nosocomiales en pacientes que reciben oxigenación por membrana extracorpórea / Risk factors for nosocomial infections in patients receiving extracorporeal membrane oxygenation supportive therapy

Antecedentes y objetivo: El objetivo de este estudio fue analizar los factores de riesgo de la infección nosocomial (IN) en pacientes que reciben soporte de extracorporeal membrane oxygenation (ECMO, «oxigenación por membrana extracorpórea»). Pacientes y métodos: Se recolectaron los datos clínicos de las IN de los pacientes que recibieron tratamiento de soporte ECMO, analizándose retrospectivamente. Resultados: Entre los 75 pacientes con ECMO, se encontró que 20 habían desarrollado IN (tasa de infección del 26,7%), aislándose un total de 58 patógenos, incluyendo 43 cepas de bacterias gramnegativas (74,1%) y 15 cepas de bacterias grampositivas (25,9%). Las cepas resistentes a múltiples fármacos se hallaban altamente concentradas, componiéndose principalmente de Acinetobacter baumannii, Pseudomonas aeruginosa y estafilococos coagulasa negativos. La incidencia de IN se relacionó con la duración del tratamiento de soporte ECMO y la estancia hospitalaria total, siendo las diferencias estadísticamente significativas (p<0,05). Un período prolongado de soporte ECMO ampliaba la estancia hospitalaria, aunque no incrementaba la tasa de mortalidad. Sin embargo, la elevación del nivel de ácido láctico incrementaba la tasa de mortalidad en esta población de estudio. Conclusiones: Las IN secundarias asociadas a ECMO guardaron una correlación considerable con la duración de la estancia hospitalaria y la duración del soporte ECMO. Por tanto, para reducir la incidencia de las IN asociadas a ECMO, deberán aplicarse estrategias en aras de reducir la duración del tratamiento de soporte ECMO y evitar la hospitalización prolongada, cuando ello sea posible (AU)

Background and objective: The aim of this study was to analyze risk factors for nosocomial infection (NI) in patients receiving extracorporeal membrane oxygenation (ECMO) support. Patients and methods: Clinical NI data were collected from patients who received ECMO support therapy, and analyzed retrospectively. Results: Among 75 ECMO patients, 20 were found to have developed NI (infection rate 26.7%); a total of 58 pathogens were isolated, including 43 strains of gram-negative bacteria (74.1%) and 15 strains of gram-positive bacteria (25.9%). Multi-drug resistant strains were highly concentrated and were mainly shown to be Acinetobacter baumannii, Pseudomonas aeruginosa, and coagulase-negative staphylococci. Incidence of NI was related to the duration of ECMO support therapy and the total length of hospital stay, and the differences were statistically significant (P<.05). A prolonged period of ECMO support extended the hospital stay, but it did not increase the mortality rate. However, an elevated level of lactic acid increased the mortality rate in this study population. Conclusions: ECMO-associated secondary NIs correlated significantly with the length of hospital stay and with the duration of ECMO support. Therefore, to reduce the incidence of ECMO-associated NIs, preventive strategies that aim to shorten the duration of ECMO support therapy and avoid lengthy hospitalization should be applied, wherever possible (AU)

Risk factors for nosocomial infections in patients receiving extracorporeal membrane oxygenation supportive therapy. / Factores de riesgo de las infecciones nosocomiales en pacientes que reciben oxigenación por membrana extracorpórea.

BACKGROUND AND OBJECTIVE: The aim of this study was to analyze risk factors for nosocomial infection (NI) in patients receiving extracorporeal membrane oxygenation (ECMO) support. PATIENTS AND METHODS: Clinical NI data were collected from patients who received ECMO support therapy, and analyzed retrospectively. RESULTS: Among 75 ECMO patients, 20 were found to have developed NI (infection rate 26.7%); a total of 58 pathogens were isolated, including 43 strains of gram-negative bacteria (74.1%) and 15 strains of gram-positive bacteria (25.9%). Multi-drug resistant strains were highly concentrated and were mainly shown to be Acinetobacter baumannii, Pseudomonas aeruginosa, and coagulase-negative staphylococci. Incidence of NI was related to the duration of ECMO support therapy and the total length of hospital stay, and the differences were statistically significant (P<.05). A prolonged period of ECMO support extended the hospital stay, but it did not increase the mortality rate. However, an elevated level of lactic acid increased the mortality rate in this study population. CONCLUSIONS: ECMO-associated secondary NIs correlated significantly with the length of hospital stay and with the duration of ECMO support. Therefore, to reduce the incidence of ECMO-associated NIs, preventive strategies that aim to shorten the duration of ECMO support therapy and avoid lengthy hospitalization should be applied, wherever possible.

Potential effects of climate change on geographic distribution of the Tertiary relict tree species Davidia involucrata in China.

This study, using species distribution modeling (involving a new approach that allows for uncertainty), predicts the distribution of climatically suitable areas prevailing during the mid-Holocene, the Last Glacial Maximum (LGM), and at present, and estimates the potential formation of new habitats in 2070 of the endangered and rare Tertiary relict tree Davidia involucrata Baill. The results regarding the mid-Holocene and the LGM demonstrate that south-central and southwestern China have been long-term stable refugia, and that the current distribution is limited to the prehistoric refugia. Given future distribution under six possible climate scenarios, only some parts of the current range of D. involucrata in the mid-high mountains of south-central and southwestern China would be maintained, while some shift west into higher mountains would occur. Our results show that the predicted suitable area offering high probability (0.5‒1) accounts for an average of only 29.2% among the models predicted for the future (2070), making D. involucrata highly vulnerable. We assess and propose priority protected areas in light of climate change. The information provided will also be relevant in planning conservation of other paleoendemic species having ecological traits and distribution ranges comparable to those of D. involucrata.

Utility of multiple-locus variant-repeat analysis method for the outbreak of the Pseudomonas aeruginosa isolates.

BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) predominated in hospitals. METHODS: In order to determine the source of the outbreak and take effective measures to prevent the spread, we tested their relationships between the strains. 97 P. aeruginosa samples were analyzed by multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) method. In order to identify a minimal subset that could provide high discrimination, we evaluated the ability of various VNTR sets. RESULTS: The result showed all of the 11 loci displayed high discrimination, and the lowest loci was ms223 (h = 0.59). The 97 strains were all discriminated (HGDI = 1.0000). The top 7-locus set produced a HGDI value of 1.0000, which was the same as the 11-locus set. The 4-locus set had a HGDI value of 0.9972 with a clustering rate of 11.3%. The strains were divided into four groups based on the phylogenetic clustering and genotypic characteristics. There were obvious differences among the four groups regarding the drug-resistance patterns of Imipenem, Ciprofloxacin, Ceftazidime, Levofloxacin, Meropenem, Piperacillin, Cefepime, Aztreonam (p < 0.05). CONCLUSIONS: In conclusion, the transmission of the strains was not found in this study. The 7-locus set yielded a high discrimination, while for an easier and more robust MLVA scheme, the number of markers can be reduced to 4 loci of ms212, ms211, ms213, and ms142. These four strains from four inpatients in the same ward displayed the same drug resistance spectrum. The MLVA genotype results showed the four strains had the same gene structures. The four patients were from the same treatment group. They showed the IMP-1 allele and belonged to the aac (6')-I type, and there was a deletion of the OprD2 gene in four strains, supporting the MLVA results in suggesting that they are similar.

Analytical performances and heart failure research of the BNP and NT-proBNP assays on the Cobas E601 and ADVIA Centaur.

BACKGROUND: The analytical performances of the NT-proBNP and BNP assays on the Cobas E601 and ADVIA Centaur were thoroughly evaluated. In addition, the values of BNP and NT-proBNP, which are heart failure markers, were compared in the diagnosis of HF patients with or without acute cerebral infarction since they could also be elevated in ischemic stroke. METHODS: Clinical and Laboratory Standards Institute (CLSI) documents were employed in the analytical evaluation of NT-proBNP and BNP assays on the Cobas E601 and ADVIA Centaur. Then 100 heart failure patients and 103 cerebral infarction complicated with heart failure patients, who had been diagnosed by clinical doctors blinded to NT-proBNP and BNP concentrations, were chosen to compare their values in the diagnosis of heart failure with or without acute cerebral infarction. RESULTS: The NT-proBNP and BNP methods are precise and accurate (total CV < 2.9%, deviation < 3.6%), have wide dynamic measuring ranges (8 pg/mL to 35 126 pg/mL and 2.0 pg/mL to 5094 pg/mL, respectively) with maximum dilutability of 1:2, and are free of common interferences. The most suitable sample types for NT-proBNP and BNP are serum and EDTA plasma, respectively, and both methods correlate well in simple-HF patients. Unlike BNP, the level of NT-proBNP is much higher in HF patients with acute cerebral infarction (p < 0.001). The Cobas E601 and ADVIA Centaur systems have good analytical performances. CONCLUSIONS: In HF patients with acute cerebral infarction, the NT-proBNP and BNP levels did not correlate and thus had implications for clinical diagnosis.