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1.
Sci Total Environ ; 915: 170157, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38242447

RESUMO

Changes in habitat characteristics are known to have profound effects on biotic communities and their functional traits. In the context of an urban-rural gradient, urbanisation drastically alters abiotic characteristics, e.g., by increasing environmental temperatures and through light pollution. These abiotic changes significantly impact the functional traits of organisms, particularly insects. Furthermore, changes in habitat characteristics also drive changes in the behavioural traits of animals, allowing them to adapt and thrive in new environments. In our study, we focused on the synanthropic ant species Lasius niger as a model organism. We conducted nocturnal field observations and complemented them with laboratory experiments to investigate the influence of night warming (NW) associated with Urban Heat Islands (UHI), light pollution (ALAN), and habitat type on ant foraging behaviour. In addition, we investigated the influence of elevated temperatures on brood development and worker mortality. Our findings revealed that urban populations of L. niger were generally more active during the night compared to their rural counterparts, although the magnitude of this difference varied with specific city characteristics. In laboratory settings, higher temperatures and continuous illumination were associated with increased activity level in ants, again differing between urban and rural populations. Rural ants exhibited more locomotion compared to their urban counterparts when maintained under identical conditions, which might enable them to forage more effectively in a potentially more challenging environment. High temperatures decreased the developmental time of brood from both habitat types and increased worker mortality, although rural colonies were more strongly affected. Overall, our study provides novel insights into the influence of urban environmental stressors on the foraging activity pattern and colony development of ants. Such stressors can be important for the establishment and spread of synanthropic ant species, including invasive ones, and the biotic homogenization of anthropogenic ecosystems.


Assuntos
Formigas , Ecossistema , Animais , Cidades , Níger , Temperatura Alta
2.
Insectes Soc ; 65(2): 275-280, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29706662

RESUMO

Ant richness and abundance are negatively affected by the invasion of alien goldenrods (Solidago sp.). However, little is known about the mechanisms standing behind the impact of the invaders on ant life history, such as colony investments in growth and reproduction. We examined this problem of the investments of Myrmica rubra ant colonies living in different grasslands invaded and non-invaded by goldenrods. Altogether, 47 colonies were analysed; and for each colony, we calculated the number of queens, workers and the production of young workers, gynes, and males. We found that colonies from invaded meadows are smaller in size, but have a similar number of adult queens compared to colonies from non-invaded sites. We also found different brood investments among colonies from invaded and non-invaded meadows-colonies from non-invaded meadows produce more young workers and invest more in growth, whereas colonies from invaded meadows invest more in reproduction through higher gyne production. Male production was at a similar level in colonies from both habitat types. The observed patterns may be explained by the effect of various environmental factors occurring in both grassland types, such as stress in changed habitats, higher competition among gynes in non-invaded grasslands, or finally, by the adaptive colony-level response of ants to stress. The higher production of gynes observed in the invaded grasslands may support dispersal and enhance the probability of establishing a colony in a more favourable location.

3.
Sci Rep ; 6: 38416, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27929100

RESUMO

The neuropeptide oxytocin has been shown to affect social interaction. Meanwhile, the underlying mechanism remains highly debated. Using an interpersonal finger-tapping paradigm, we investigated whether oxytocin affects the ability to synchronise with and adapt to the behaviour of others. Dyads received either oxytocin or a non-active placebo, intranasally. We show that in conditions where one dyad-member was tapping to another unresponsive dyad-member - i.e. one was following another who was leading/self-pacing - dyads given oxytocin were more synchronised than dyads given placebo. However, there was no effect when following a regular metronome or when both tappers were mutually adapting to each other. Furthermore, relative to their self-paced tapping partners, oxytocin followers were less variable than placebo followers. Our data suggests that oxytocin improves synchronisation to an unresponsive partner's behaviour through a reduction in tapping-variability. Hence, oxytocin may facilitate social interaction by enhancing sensorimotor predictions supporting interpersonal synchronisation. The study thus provides novel perspectives on how neurobiological processes relate to socio-psychological behaviour and contributes to the growing evidence that synchronisation and prediction are central to social cognition.


Assuntos
Relações Interpessoais , Liderança , Ocitocina/fisiologia , Administração Intranasal , Adolescente , Adulto , Humanos , Masculino , Ocitocina/administração & dosagem , Ocitocina/metabolismo
4.
Ann Oncol ; 27(10): 1887-94, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27502703

RESUMO

BACKGROUND: Concurrent chemoradiation is the standard of care in non-operable stage III non-small-cell lung cancer (NSCLC). Data have suggested a benefit of dose escalation; however, results from the randomized dose-escalation trial RTOG 0617 revealed a lower survival rate with high-dose radiation. To evaluate the impact of dose escalation on overall survival (OS) in stage III NSCLC treated with chemoradiotherapy outside the controlled setting of a randomized trial, we carried out an observational, population-based investigation of the National Cancer Database (NCDB). PATIENTS AND METHODS: A total of 33 566 patients with stage III NSCLC treated with chemoradiation from 2004 to 2012 and radiation doses between 59.4 and 85 Gy were included. The primary end point was OS, with median survival calculated via Kaplan-Meier. Univariate, multivariable and propensity-score matching analyses were carried out. RESULTS: Patients were stratified by dose with median OS of: 18.8, 19.8 and 21.6 months for cohorts receiving 59.4-60, 61-69 and ≥70 Gy, respectively (P < 0.001). Granular dose analyses were carried out demonstrating increased OS with increasing radiation dose: median survival of 18.8, 21.1, 22.0 and 21.0 months for 59.4-60, 66, 70 and ≥71 Gy, respectively. While 66, 70 and ≥71 Gy resulted in increased OS in comparison with 59.4-60 Gy, no significant difference in OS was observed when comparing 66 with ≥71 Gy (P = 0.38). CONCLUSIONS: Dose escalation above 60 Gy was associated with improved OS in this cohort of stage III NSCLC patients treated with chemoradiotherapy. A plateau of benefit was observed, with no additional improvement in OS with increased dose (≥71 Gy) compared with 66-70 Gy. With evidence suggesting worse OS and quality of life with increased dose, these data support investigation of the role of intermediate-dose radiation, and in the absence of randomized evidence, may be leveraged to justify utilization of intermediate-dose radiation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Quimiorradioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Ensaios Clínicos como Assunto , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida , Dosagem Radioterapêutica
5.
Anal Chem ; 85(19): 9092-100, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23947293

RESUMO

In this manuscript, we discuss the development and clinical use of a thermoplastic modular microsystem for the high-throughput analysis of CTCs directly from whole blood. The modular system offers some innovative features that address challenges currently associated with many CTC platforms; it can exhaustively process 7.5 mL of blood in less than 45 min with recoveries >90%. In addition, the system automates the postselection CTC processing steps and thus, significantly reduces assay turnaround time (from selection to enumeration <1.5 h as compared to >8 h for many reported CTC platforms). The system is composed of 3 functional modules including (i) a thermoplastic CTC selection module composed of high aspect ratio (30 µm × 150 µm) channels containing anti-EpCAM antibodies that is scalable in terms of throughput by employing channel numbers ranging from 50 to 320; the channel number is user selected to accommodate the volume of blood that must be processed; (ii) an impedance sensor module for label-less CTC counting; and (iii) a staining and imaging module for the placement of released cells into a 2D array within a common imaging plane for phenotypic identification. To demonstrate the utility of this system, blood samples from patients with local resectable and metastatic pancreatic ductal adenocarcinoma (PDAC) were analyzed. We demonstrate the ability to select EpCAM positive CTCs from PDAC patients in high purity (>86%) and with excellent yields (mean = 53 CTCs per mL for metastatic PDAC patients) using our modular system. In addition, we demonstrate the ability to detect CTCs in PDAC patients with local resectable disease (mean = 11 CTCs per mL).


Assuntos
Separação Celular/métodos , Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes/patologia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Fenótipo , Células Tumorais Cultivadas
6.
Insectes Soc ; 58(3): 403-411, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21765539

RESUMO

Maculinea butterflies are social parasites of Myrmica ants. Methods to study the strength of host ant specificity in the Maculinea-Myrmica association include research on chemical and acoustic mimicry as well as experiments on ant adoption and rearing behaviour of Maculinea larvae. Here we present results of laboratory experiments on adoption, survival, development and integration of M. teleius larvae within the nests of different Myrmica host species, with the objective of quantifying the degree of specialization of this Maculinea species. In the laboratory, a total of 94 nests of four Myrmica species: M. scabrinodis, M. rubra, M.ruginodis and M. rugulosa were used. Nests of M. rubra and M. rugulosa adopted M. teleius larvae more readily and quickly than M. ruginodis colonies. No significant differences were found in the survival rates of M. teleius larvae reared by different ant species. Early larval growth of M. teleius larvae differed slightly among nests of four Myrmica host species. Larvae reared by colonies of M. rugulosa which were the heaviest at the beginning of larval development had the lowest mean larval body mass after 18 weeks compared to those reared by other Myrmica species. None of the M.teleius larvae was carried by M. scabrinodis or M. rubra workers after ant nests were destroyed, which suggests a lack of integration with host colonies. Results indicate that Myrmica species coming from the same site differ in their ability to adopt and rear M. teleius larvae but there was no obvious adaptation of this butterfly species to one of the host ant species. This may explain why, under natural conditions, all four ants can be used as hosts of this butterfly species. Slight advantages of particular Myrmica species as hosts at certain points in butterfly larval development can be explained by the ant species biology and colony structure rather than by specialization of M. teleius.

7.
Biomed Microdevices ; 10(1): 21-33, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17659445

RESUMO

A 96-well solid-phase reversible immobilization (SPRI) reactor plate was designed to demonstrate functional titer plate-based microfluidic platforms. Nickel, large area mold inserts were fabricated using an SU-8 based, UV-LIGA technique on 150 mm diameter silicon substrates. Prior to UV exposure, the prebaked SU-8 resist was flycut to reduce the total thickness variation to less than 5 mum. Excellent UV lithography results, with highly vertical sidewalls, were obtained in the SU-8 by using an UV filter to remove high absorbance wavelengths below 350 nm. Overplating of nickel in the SU-8 patterns produced high quality, high precision, metal mold inserts, which were used to replicate titer plate-based SPRI reactors using hot embossing of polycarbonate (PC). Optimized molding conditions yielded good feature replication fidelity and feature location integrity over the entire surface area. Thermal fusion bonding of the molded PC chips at 150 degrees C resulted in leak-free sealing, which was verified in leakage tests using a fluorescent dye. The assembled SPRI reactor was used for simple, fast purification of genomic DNA from whole cell lysates of several bacterial species, which was verified by PCR amplification of the purified genomic DNA.


Assuntos
DNA/isolamento & purificação , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos
8.
Postgrad Med ; 108(5): 111-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043084

RESUMO

Appropriate antidepressant dosing and trial duration are crucial for successful treatment of depression. Before prescribing an antidepressant, primary care physicians should take into account each patient's history, responses to previous antidepressants, depressive symptoms, coexisting illnesses, and current prescriptions. Physicians must be able to help patients manage side effects and know when to discontinue treatment, switch antidepressants, or refer patients to a psychiatrist.


Assuntos
Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Antidepressivos/efeitos adversos , Depressão/psicologia , Depressão/terapia , Esquema de Medicação , Humanos , Atenção Primária à Saúde , Psiquiatria , Encaminhamento e Consulta
9.
Anal Chem ; 72(16): 3793-804, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10959965

RESUMO

Standard electrochemical data for high-quality, boron-doped diamond thin-film electrodes are presented. Films from two different sources were compared (NRL and USU) and both were highly conductive, hydrogen-terminated, and polycrystalline. The films are acid washed and hydrogen plasma treated prior to use to remove nondiamond carbon impurity phases and to hydrogen terminate the surface. The boron-doping level of the NRL film was estimated to be in the mid 1019 B/cm3 range, and the boron-doping level of the USU films was approximately 5 x 10(20) B/cm(-3) based on boron nuclear reaction analysis. The electrochemical response was evaluated using Fe-(CN)6(3-/4-), Ru(NH3)6(3+/2+), IrCl6(2-/3-), methyl viologen, dopamine, ascorbic acid, Fe(3+/2+), and chlorpromazine. Comparisons are made between the apparent heterogeneous electron-transfer rate constants, k0(app), observed at these high-quality diamond films and the rate constants reported in the literature for freshly activated glassy carbon. Ru(NH3)6(3+/2+), IrCl6(2-/3-), methyl viologen, and chlorpromazine all involve electron transfer that is insensitive to the diamond surface microstructure and chemistry with k0(app) in the 10(-2)-10(-1) cm/s range. The rate constants are mainly influenced by the electronic properites of the films. Fe(CN)6(3-/4-) undergoes electron transfer that is extremely sensitive to the surface chemistry with k0(app) in the range of 10(-2)-10(-1) cm/s at the hydrogen-terminated surface. An oxygen surface termination severely inhibits the rate of electron transfer. Fe(3+/2+) undergoes slow electron transfer at the hydrogen-terminated surface with k0(app) near 10(-5) cm/s. The rate of electron transfer at sp2 carbon electrodes is known to be mediated by surface carbonyl functionalities; however, this inner-sphere, catalytic pathway is absent on diamond due to the hydrogen termination. Dopamine, like other catechol and catecholamines, undergoes sluggish electron transfer with k0(app) between 10(-4) and 10(-5) cm/s. Converting the surface to an oxygen termination has little effect on k0(app). The slow kinetics may be related to weak adsorption of these analytes on the diamond surface. Ascorbic acid oxidation is very sensitive to the surface termination with the most negative Ep(ox) observed at the hydrogen-terminated surface. An oxygen surface termination shifts Ep(ox) positive by some 250 mV or more. An interfacial energy diagram is proposed to explain the electron transfer whereby the midgap density of states results primarily from the boron doping level and the lattice hydrogen. The films were additionally characterized by scanning electron microscopy and micro-Raman imaging spectroscopy. The cyclic voltammetric and kinetic data presented can serve as a benchmark for research groups evaluating the electrochemical properties of semimetallic (i.e., conductive), hydrogen-terminated, polycrystalline diamond.

10.
Vet Immunol Immunopathol ; 62(4): 297-307, 1998 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-9646435

RESUMO

The effect of two intravenous (i.v.) injections of low doses of lipopolysaccharide (LPS)(0.1 microgram/kg of body weight) administered at 7-day intervals on the systemic release of tumor necrosis factor (TNF) and interferon (IFN), on the rectal temperature, breathing and heart rate, and on packed cell volume (PCV), plasma glucose concentration, white blood cell (WBC) counts in 3-week-old calves, was estimated. The first injection of LPS caused a significant increase in breathing and heart rate, rectal temperature, prolonged hypoglycemia and leukopenia, but no significant changes in PCV were observed. TNF and IFN activity peaked at 2 h after LPS injection and disappeared from circulation by 4 h and 5 h, respectively. After the second injection of LPS, the reaction of calves was similar to that observed after the first injection, however, the breathing rate and TNF systemic production were significantly reduced. The results obtained indicate that a low dose of LPS leads to the development of 'late' tolerance manifested by hyporeactivity to TNF production but with maintained responsivity to IFN production, pyrogenic, hypoglycemic and leukemic response to the second injection of LPS. In conclusion, these results demonstrate that the tolerance response is not universal to all hematologic and immunologic parameters, and that the response needs to be evaluated with respect to the specific variable.


Assuntos
Bovinos/imunologia , Interferons/sangue , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Animais , Glicemia/metabolismo , Bovinos/sangue , Bovinos/fisiologia , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/fisiopatologia , Tolerância a Medicamentos , Endotoxemia/etiologia , Endotoxemia/fisiopatologia , Endotoxemia/veterinária , Índices de Eritrócitos , Febre/etiologia , Infecções por Bactérias Gram-Negativas/etiologia , Infecções por Bactérias Gram-Negativas/fisiopatologia , Infecções por Bactérias Gram-Negativas/veterinária , Frequência Cardíaca , Hipoglicemia/etiologia , Hipoglicemia/veterinária , Contagem de Leucócitos , Leucopenia/etiologia , Leucopenia/veterinária , Masculino , Respiração
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