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1.
Aesthetic Plast Surg ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578308

RESUMO

BACKGROUND: Levator aponeurectomy is a common operation for mild to moderate blepharoptosis. The accuracy of ptosis correction relied on intraoperative judgement when patients were under local anesthesia. For patients who must receive the operation under general anesthesia, it would be an issue to determine how much length of levator aponeurosis to shorten. To solve this issue, we collected data from patients who underwent the operation under local anesthesia and concluded an algorithm. METHODS: This single-center, prospective bivariate regression study allocated patients of mild to moderate congenital blepharoptosis who received levator aponeurectomy under local anesthesia. Preoperative MRD1 and levator function, intraoperative amount of levator aponeurotic shortening, and postoperative MRD1 were measured. The follow-up period was right after the operation. RESULTS: Twenty-nine patients were included in this trial. Two subjects exited because of not receiving allocated operation and data of the other 27 subjects (including 34 eyelids) were analyzed. A scatter diagram was drawn where x axis referred to levator function and y axis referred to the ratio of the amount of shortening of levator aponeurosis over the height of MRD1 correction. Linear regression showed y = - 0.2717*x + 5.026, R2 = 0.8553. CONCLUSION: A modified algorithm to predict the amount of shortening of levator aponeurosis based on levator function and height of ptosis correction was concluded with better accuracy and clinical feasibility. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

2.
Medicina (Kaunas) ; 60(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38541224

RESUMO

Background and Objectives: This study examined the influence of stationary bikes and elliptical machines on knee movement and joint load during exercise. Materials and Methods: Twelve healthy male participants engaged in pedaling exercises on stationary bikes and elliptical machines at speeds of 50 and 70 revolutions per minute (rpm). Knee movement and joint load were assessed using a motion analysis system. Results: The results indicated that elliptical machines induced higher knee joint torque compared to stationary bikes. Notably, peak torque occurred at different joint angles, with stationary bikes reaching an earlier peak at 70°-110° and elliptical machines showing a later peak at 135°-180°. Increased pedaling speed correlated with higher peak knee joint torque on both machines. With the elliptical machine, a higher pedaling frequency correlated with increased peak forces on the knee and ankle joints, as well as vertically. Interestingly, both types of equipment were associated with enhanced peak knee joint torques during high-speed pedaling. Conversely, constant pedaling on elliptical machines limited the ankle angle and could induce inward rotation. Conclusions: This study focused on knee joint torque variations during pedaling on indoor stationary bicycles and elliptical machines. Elliptical machines showed higher peak values of forces and torque, particularly during the propulsive and recovery phases, indicating potential challenges to the knee joint. Notably, peak pedal angles occurred earlier on indoor stationary bicycles, emphasizing the impact of equipment choice on joint kinetics.


Assuntos
Ciclismo , Articulação do Joelho , Humanos , Masculino , Fenômenos Biomecânicos , Joelho , Extremidade Inferior
3.
New Phytol ; 238(6): 2594-2606, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36918476

RESUMO

Secondary invasions in which nontarget invaders expand following eradication of a target invader commonly occur in habitats with multiple invasive plant species and can prevent recovery of native communities. However, the dynamics and mechanisms of secondary invasion remain unclear. Here, we conducted a common garden experiment to test underlying mechanisms of secondary invasion for 14 nontarget invaders after biological control of Ambrosia artemisiifolia in two consecutive years. We found secondary invasion for all tested nontarget invaders, but secondary invasiveness (change relative to natives) varied with species and time. Specifically, secondary invasiveness depended most strongly on phylogenetic relatedness between the target and nontarget invaders in the first year with closely related nontarget invaders being most invasive. By contrast, secondary invasiveness in the second year was mostly driven by functional traits with taller nontarget invaders or those with higher specific leaf area, or smaller seeds especially invasive. Our study indicates that secondary invasion is likely to occur wherever other invasive plants co-occur with an invasive species targeted for control. Furthermore, the most problematic invaders will initially be species closely related to the target invader but then species with rapid growth and high reproduction are most likely to be more aggressive secondary invaders.


Assuntos
Ecossistema , Plantas , Filogenia , Espécies Introduzidas , Sementes
4.
Ecol Appl ; : e2805, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36583667

RESUMO

Temporal fluctuation in nutrient availability generally promotes the growth of exotic plant species and has been recognized as an important driver of exotic plant invasions. However, little is known about how the impact of fluctuating nutrients on exotic species is dependent on the availability of other resources, although most ecosystems are experiencing dramatic variations in a wide variety of resources due to global change and human disturbance. Here, we explored how water availability mediates the effect of nutrient pulses on the growth of six exotic and six native plant species. We subjected individual plants of exotic and native species to well watered or water stressed conditions. For each level of water availability, we added equivalent amounts of nutrients at a constant rate, as a single large pulse, or in multiple small pulses. Under well watered conditions, nutrient pulses promoted exotic plant growth relative to nutrients supplied constantly, while they had no significant effect on natives. In contrast, under water stressed conditions, water deficiency inhibited the growth of all exotic and native species. More importantly, nutrient pulses did not increase plant growth relative to nutrients supplied constantly and these phenomena were observed for both exotic and native species. Taken together, our study shows that the impact of fluctuating nutrient availability on the growth of exotic plant species strongly depends on the variation of other resources, and that the positive effect of nutrient pulses under well watered conditions disappears under water stressed conditions. Our findings suggest that the variation in multiple resources may have complex feedback on exotic plant invasions and, therefore, it is critical to encompass multiple resources for the evaluation of fluctuating resource availability effects on exotic plant species. This will allow us to project the invasive trajectory of exotic plant species more accurately under future global change and human disturbance.

5.
Ann Bot ; 124(5): 819-827, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31318017

RESUMO

BACKGROUND AND AIMS: The strengths of biotic interactions such as herbivory are expected to decrease with increasing latitude for native species. To what extent this applies to invasive species and what the consequences of this variation are for competition among native and invasive species remain unexplored. Here, herbivore impacts on the invasive plant Alternanthera philoxeroides and its competition with the native congener A. sessilis were estimated across latitudes in China. METHODS: An common garden experiment spanning ten latitudinal degrees was conducted to test how herbivore impacts on A. philoxeroides and A. sessilis, and competition between them change with latitude. In addition, a field survey was conducted from 21°N to 36.8°N to test whether A. philoxeroides invasiveness changes with latitude in nature as a result of variations in herbivory. KEY RESULTS: In the experiment, A. sessilis cover was significantly higher than A. philoxeroides cover when they competed in the absence of herbivores, but otherwise their cover was comparable at low latitude. However, A. philoxeroides cover was always higher on average than A. sessilis cover at middle latitude. At high latitude, only A. sessilis emerged in the second year. Herbivore abundance decreased with latitude and A. philoxeroides emerged earlier than A. sessilis at middle latitude. In the field survey, the ratio of A. philoxeroides to A. sessilis cover was hump shaped with latitude. CONCLUSION: These results indicate that herbivory may promote A. philoxeroides invasion only at low latitude by altering the outcome of competition in favour of the invader and point to the importance of other factors, such as earlier emergence, in A. philoxeroides invasion at higher latitudes. These results suggest that the key factors promoting plant invasions might change with latitude, highlighting the importance of teasing apart the roles of multiple factors in plant invasions within a biogeographic framework.


Assuntos
Amaranthaceae , Herbivoria , China , Espécies Introduzidas , Plantas
6.
ISME J ; 12(12): 2811-2822, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30013163

RESUMO

Soil biota community structure can change with latitude, but the effects of changes on native plants, invasive plants, and their herbivores remain unclear. Here, we examined latitudinal variation in the soil biota community associated with the invasive plant Alternanthera philoxeroides and its native congener A. sessilis, and the effects of soil biota community variation on these plants and the beetle Agasicles hygrophila. We characterized the soil bacterial and fungal communities and root-knot nematodes of plant rhizospheres collected from 22 °N to 36.6 °N in China. Soil biota community structure changed with latitude as a function of climate and soil properties. Root-knot nematode abundance and potential soil fungal pathogen diversity (classified with FUNGuild) decreased with latitude, apparently due to higher soil pH and lower temperatures. A greenhouse experiment and lab bioassay showed native plant mass, seed production, and mass of beetles fed native foliage increased with soil collection latitude. However, there were no latitudinal patterns for the invasive plant. These results suggest that invasive and native plants and, consequently, their herbivores have different responses to latitudinal changes in soil-borne enemies, potentially creating spatial variation in enemy release or biotic resistance. This highlights the importance of linking above- and below-ground multitrophic interactions to explore the role of soil biota in non-native plant invasions with a biogeographic approach.


Assuntos
Amaranthaceae/microbiologia , Biota , Besouros/fisiologia , Microbiologia do Solo , Solo/parasitologia , Amaranthaceae/crescimento & desenvolvimento , Amaranthaceae/parasitologia , Animais , Bactérias , China , Clima , Fungos/fisiologia , Geografia , Espécies Introduzidas , Nematoides/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Rizosfera , Sementes/crescimento & desenvolvimento , Sementes/microbiologia , Sementes/parasitologia
7.
New Phytol ; 211(4): 1371-81, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27094757

RESUMO

Climate warming may affect biological invasions by altering competition between native and non-native species, but these effects may depend on biotic interactions. In field surveys at 33 sites in China along a latitudinal and temperature gradient from 21°N to 30.5°N and a 2-yr field experiment at 30.5°N, we tested the role of the biocontrol beetle Agasicles hygrophila in mediating warming effects on competition between the invasive plant Alternanthera philoxeroides and the native plant Alternanthera sessilis. In surveys, native populations were perennial below 25.8°N but only annual populations were found above 26.5°N where the invader dominated the community. Beetles were present throughout the gradient. Experimental warming (+ 1.8°C) increased native plant performance directly by shifting its lifecycle from annual to perennial, and indirectly by releasing the native from competition via disproportionate increases in herbivory on the invader. Consequently, warming shifted the plant community from invader-dominated to native-dominated but only in the presence of the beetle. Our results show that herbivores can play a critical role in determining warming effects on plant communities and species invasions. Understanding how biotic interactions shape responses of communities to climate change is crucial for predicting the risk of plant invasions.


Assuntos
Amaranthaceae/fisiologia , Mudança Climática , Besouros/fisiologia , Espécies Introduzidas , Controle Biológico de Vetores , Animais , Biomassa , Germinação , Modelos Biológicos , Caules de Planta/anatomia & histologia , Análise de Regressão , Plântula/fisiologia , Sementes/fisiologia , Especificidade da Espécie
8.
Ecol Lett ; 18(1): 48-56, 2015 01.
Artigo em Inglês | MEDLINE | ID: mdl-25376303

RESUMO

Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from annual to perennial. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species.


Assuntos
Amaranthaceae , Agentes de Controle Biológico , Mudança Climática , Besouros , Herbivoria , Animais , China , Ecossistema , Espécies Introduzidas
9.
Chin Med J (Engl) ; 124(19): 2993-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22040542

RESUMO

BACKGROUND: Acute severe biliary pancreatitis (ASBP) is a severe and fatal disease, and the expenditure is huge and therapeutic effects are still not satisfactory. This study aimed to improve the therapeutic effects and reduce the expenditure of ASBP treatment. METHODS: One hundred and five patients diagnosed with ASBP were referred to our department from January 2004 to July 2009. Diagnosis was based on the 2007 criteria of the Chinese Society of Surgery. Patients were divided into two groups; the E group: 50 patients who underwent endoscopic retrograde choledochopancreatography (ERCP) + endoscopic sphincterotomy (EST) + endoscopic lithotripsy basket (ESR) + endoscopic retrograde biliary drainage (ERBD) and enteral nutrition (EN), and the R group: 55 patients who underwent traditional treatment without ERCP. Subsequently, subjective symptoms, signs, biochemical analysis, serum endotoxin, tumor necrosis factor a, grades by computed tomography (CT), cost of hospitalization and length of stay were compared between the two groups. RESULTS: All enrolled patients complied well with all therapeutic regimens. Endoscopic therapy that combined EN could significantly improve symptoms, clinical signs, laboratory values, tumor necrosis factor a and endotoxin while significantly reducing hospital expenditure and length of hospital stay. The experimental findings revealed that there were obvious advantages in the E group compared with the R group. CONCLUSIONS: Endoscopic therapy combined with EN is an effective, safe and economic therapeutic regimen of ASBP.


Assuntos
Endoscopia do Sistema Digestório , Nutrição Enteral , Pancreatite/terapia , Doença Aguda , Colangiopancreatografia Retrógrada Endoscópica , Drenagem , Feminino , Cálculos Biliares/complicações , Humanos , Litotripsia , Masculino , Pessoa de Meia-Idade , Pancreatite/etiologia , Esfinterotomia Endoscópica
10.
Res Microbiol ; 162(7): 671-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21704702

RESUMO

A novel and multiple metal(loid)-resistant strain Comamonas testosteroni S44 with a high Zn(2+) resistance level (10 mM) was isolated. To understand the molecular basis for the high zinc resistance, whole genome sequencing was performed and revealed a large number of genes encoding putative metal(loid) resistance proteins, mobile genetic elements (MGEs) and horizontal gene transfer (HGT) events that may have occurred to adapt to a metal(loid)-contaminated environment. In particular, 9 putative Zn(2+) transporters [4 znt operons encoding putative Zn(2+)-translocating P-type ATPases and 5 czc operons encoding putative RND-driven (resistance, nodulation, cell division protein family)] tripartite protein complexes were identified. Real-time RT-PCR analysis revealed that the four zntA-like genes were all induced by Zn(2+), while czcA genes were either Zn(2+)-induced or downregulated by Zn(2+). Furthermore, a zntR1A1 operon encoding a ZntR-type regulator and a P-type ATPase was studied in detail. The zntR1 deletion strain (S44ΔzntR1) displayed intermediate resistance to Zn(2+) (6 mM) and accumulated more intracellular Zn(2+). Reporter gene expression assays indicated that ZntR1 responded to Zn(2+), Cd(2+) and Pb(2+), with Zn(2+) being the best inducer. Gene transcription analysis indicated that ZntR1 was a regulator for transcription of zntA1, while other putative ZntR-type regulators may also regulate the transcription expression of zntA1.


Assuntos
Comamonas testosteroni/genética , Genoma Bacteriano , Zinco/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transporte Biológico , Comamonas testosteroni/classificação , Comamonas testosteroni/isolamento & purificação , Comamonas testosteroni/metabolismo , Regulação Bacteriana da Expressão Gênica , Dados de Sequência Molecular , Microbiologia do Solo
11.
Int J Syst Evol Microbiol ; 61(Pt 8): 1906-1911, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20833883

RESUMO

A Gram-positive-staining, aerobic, moderately halophilic bacterium, designated strain Y32(T), was isolated from subsurface soil of the Sanwei salt field, Yancheng, Jiangsu province, South-east China. The cell-wall peptidoglycan type of strain Y32(T) was meso-diaminopimelic acid. The menaquinone was menaquinone-7 (MK-7). The major fatty acids were anteiso-C(15 : 0) and iso-C(15 : 0) and the DNA G+C content of strain Y32(T) was 40.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Y32(T) was closely related to the type strains of the genus Pontibacillus. The 16S rRNA gene sequence similarities of strain Y32(T) with the type strains of species of the genus Pontibacillus were 97.8 % (Pontibacillus marinus KCTC 3917(T)), 96.9 % (Pontibacillus chungwhensis BH030062(T)), 96.8 % (Pontibacillus litoralis JSM 072002(T)) and 96.0 % (Pontibacillus halophilus JSM 076056(T)). DNA-DNA relatedness between strain Y32(T) and P. marinus KCTC 3917(T) was 42 %. On the basis of phenotypic, chemotaxonomic and phylogenetic evidences, strain Y32(T) was found to be affiliated to the genus Pontibacillus, but was clearly differentiated from other members of this genus. Strain Y32(T) represents a novel member of the genus, for which the name Pontibacillus yanchengensis sp. nov. is proposed. The type strain is Y32(T) ( = CGMCC 1.10680(T) = CCTCC AB209311(T) = NRRL B-59408(T)).


Assuntos
Bacillaceae/classificação , Bacillaceae/isolamento & purificação , Cloreto de Sódio/metabolismo , Microbiologia do Solo , Bacillaceae/genética , Bacillaceae/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
12.
J Hazard Mater ; 185(2-3): 682-8, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-20952126

RESUMO

Lysinibacillus fusiformis ZC1 isolated from chromium (Cr) contaminated wastewater of a metal electroplating factory displayed high chromate [Cr(VI)] resistance with a minimal inhibitory concentration (MIC) of 60mM in R2A medium. L. fusiformis ZC1 showed resistances to multiple metals (Cu, Ni, Co, Hg, Cd and Ag) and a metalloid (As). This bacterium exhibited an extremely rapid Cr(VI) reduction capability. It almost completely reduced 1mM K(2)CrO(4) in 12h. The Cr(VI) reduction ability of L. fusiformis ZC1 was enhanced by sodium acetate and NADH. By whole genome sequence analysis, strain ZC1 was found to contain large numbers of metal(loid) resistance genes. Specifically, a chrA gene encoding a putative chromate transporter conferring chromate resistance was identified. The chromate resistance was constitutive in both phenotypic and gene expression analyses. Furthermore, we found a yieF gene and several genes encoding reductases that were possibly involved in chromate reduction. Expression of adjacent putative chromate reduction related genes, nitR and yieF, was found to be constitutive. The large numbers of NADH-dependent chromate reductase genes may be responsible for the rapid chromate reduction in order to detoxify Cr(VI) and survive in the harsh wastewater environment.


Assuntos
Bacillaceae/metabolismo , Cromatos/metabolismo , Genoma Bacteriano , Bacillaceae/genética , Bacillaceae/ultraestrutura , Sequência de Bases , Carbono/metabolismo , Primers do DNA , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
BMC Microbiol ; 10: 221, 2010 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-20723231

RESUMO

BACKGROUND: Chromium is a toxic heavy metal, which primarily exists in two inorganic forms, Cr(VI) and Cr(III). Chromate [Cr(VI)] is carcinogenic, mutational, and teratogenic due to its strong oxidizing nature. Biotransformation of Cr(VI) to less-toxic Cr(III) by chromate-resistant and reducing bacteria has offered an ecological and economical option for chromate detoxification and bioremediation. However, knowledge of the genetic determinants for chromate resistance and reduction has been limited so far. Our main aim was to investigate chromate resistance and reduction by Bacillus cereus SJ1, and to further study the underlying mechanisms at the molecular level using the obtained genome sequence. RESULTS: Bacillus cereus SJ1 isolated from chromium-contaminated wastewater of a metal electroplating factory displayed high Cr(VI) resistance with a minimal inhibitory concentration (MIC) of 30 mM when induced with Cr(VI). A complete bacterial reduction of 1 mM Cr(VI) was achieved within 57 h. By genome sequence analysis, a putative chromate transport operon, chrIA1, and two additional chrA genes encoding putative chromate transporters that likely confer chromate resistance were identified. Furthermore, we also found an azoreductase gene azoR and four nitroreductase genes nitR possibly involved in chromate reduction. Using reverse transcription PCR (RT-PCR) technology, it was shown that expression of adjacent genes chrA1 and chrI was induced in response to Cr(VI) but expression of the other two chromate transporter genes chrA2 and chrA3 was constitutive. In contrast, chromate reduction was constitutive in both phenotypic and gene expression analyses. The presence of a resolvase gene upstream of chrIA1, an arsenic resistance operon and a gene encoding Tn7-like transposition proteins ABBCCCD downstream of chrIA1 in B. cereus SJ1 implied the possibility of recent horizontal gene transfer. CONCLUSION: Our results indicate that expression of the chromate transporter gene chrA1 was inducible by Cr(VI) and most likely regulated by the putative transcriptional regulator ChrI. The bacterial Cr(VI)-resistant level was also inducible. The presence of an adjacent arsenic resistance gene cluster nearby the chrIA1 suggested that strong selective pressure by chromium and arsenic could cause bacterial horizontal gene transfer. Such events may favor the survival and increase the resistance level of B. cereus SJ1.


Assuntos
Bacillus cereus/genética , Bacillus cereus/metabolismo , Cromatos/metabolismo , Farmacorresistência Bacteriana , Genômica , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biotransformação , Cromatos/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Dados de Sequência Molecular , Oxirredução , Esgotos/microbiologia
14.
J Hazard Mater ; 176(1-3): 487-94, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20004516

RESUMO

The growth of Halobacillus sp. Y35 has been investigated in HGM hypersaline medium with different doses of As(III) and kaolin. The metabolic heat flux decreases with the increase in As(III) concentration, indicating that strain Y35 lowers their metabolic activity in order to resist the As(III) toxicity. Carbon dioxide flux, cell growth and protein synthesis rates, and total thermal effect have been, for the first time, successfully employed simultaneously to assess the effect of As(III) on strain Y35 in the absence and presence of kaolin. The relative adsorption capacity and adsorption intensity of kaolin for As(III) are higher with strain Y35 than that without strain Y35, demonstrating that it is possible to reduce the toxicity of As(III) to our environment by both using mineral adsorption and biosorption technology. Our work shows the potential application of kaolin and strain Y35 for the removal of As(III) from contaminated groundwater.


Assuntos
Arsênio/toxicidade , Euryarchaeota/efeitos dos fármacos , Caulim/farmacologia , Adsorção , Arsênio/química , Dióxido de Carbono , Metabolismo Energético , Recuperação e Remediação Ambiental , Euryarchaeota/crescimento & desenvolvimento , Caulim/química , Biossíntese de Proteínas , Purificação da Água/métodos
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