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1.
J Invertebr Pathol ; 200: 107969, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37423339

RESUMO

The two-spotted lady beetle, Adalia bipunctata L., displays warning colouration that is reinforced by the production of adaline and adalinine. These alkaloids are thought to provide defense against predation throughout all life stages of A. bipunctata and may play a role in the insect immune system. Vairimorpha (Nosema) adaliae, a microsporidium described from A. bipunctata, has minimal effects on its host (delayed larval development) when reared under optimum conditions but stress factors are shown to affect the development of microsporidiosis. The objectives of this study were to determine the effects of V. adaliae on relative alkaloid content (adaline) during A. bipunctata development, and to evaluate the combined effects of physical stress and infection on adult beetles (relative alkaloid content and infection load). First-instar larvae were isolated from uninfected and V. adaliae-infected colonies. Eggs and first-instar larvae were immediately prepared for alkaloid analysis, whereas late-instar larvae, pupae and adults were systematically processed when each reached their designated developmental stage. Upon eclosion, a subsample of beetles was exposed to varying amounts of physical agitation: control (no shaking), alternate shaking (every other day), and daily shaking. Immediately following these stress trials, alkaloid samples were collected for analysis and spore loads were assessed. Overall, relative adaline proportions increased from egg to adult. Uninfected individuals had significantly higher relative proportions of adaline than did infected individuals during early development; however, adaline content was higher in infected A. bipunctata from the third-instar onwards, when compared to their uninfected counterparts. Following exposure to physical agitation on alternate days, uninfected adults had a significantly higher relative proportion of adaline than did infected adults. Interestingly, exposure to different levels of agitation had no significant effect on alkaloid production for either uninfected or infected beetles. Mean spore counts were significantly higher for adults that were exposed to daily shaking when compared to individuals from the control and alternate shaking groups. From a biological perspective, one would expect to observe differences in alkaloid production through coccinellid development, as each successive life stage faces different external pressures and risks. When infected with the microsporidium V. adaliae, however, adaline production was reduced during early development but increased significantly in late life stages.


Assuntos
Alcaloides , Besouros , Nosema , Animais , Esporos Fúngicos , Larva
2.
J Invertebr Pathol ; 196: 107855, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36410528

RESUMO

Honey is known for its antibacterial and antifungal properties. Manuka honey was examined for its potential to manage the microsporidium Vairimorpha (Nosema) adaliae infecting Adalia bipunctata larvae. Development time for uninfected larvae fed aphids and water was 13.0 ± 0.2 days, which did not differ significantly from larvae fed aphids and manuka honey. Development of V. adaliae-infected larvae fed aphids and water was 16.3 ± 0.5 days, compared to 15.0 ± 0.2, 15.2 ± 0.3, and 15.6 ± 0.2 days for larvae fed aphids and 5 %, 10 %, or 15 % manuka honey, respectively. Development time was shorter for all honey treatments, but only those fed 5 % manuka differed significantly from the control. Control adults had 19.4 ± 3.0 spores/120 µm2, compared to 19.0 ± 2.0, 19.1 ± 2.1, and 14.3 ± 2.2, for adults provided with 5 %, 10 %, and 15 % honey, respectively. Although spore loads did not differ significantly (p > 0.05), lighter infections were observed in the group fed 15 % manuka.


Assuntos
Afídeos , Besouros , Mel , Nosema , Animais , Besouros/microbiologia , Larva , Água
3.
J Invertebr Pathol ; 175: 107443, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32687835

RESUMO

The effects of food availability and infection with the microsporidium Nosema adaliae on alkaloid production in the two-spotted lady beetle, Adalia bipunctata L., was examined. Alkaloid production (relative percent adaline in reflex-fluid) and pathogen load (spore counts) were quantified for both uninfected and N. adaliae-infected A. bipunctata. Alkaloid content was significantly higher for beetles fed irregularly than for those fed daily. For beetles infected with N. adaliae, spore counts were significantly higher for those fed irregularly compared to those fed daily. These results suggest that adaline content in reflex-fluid is influenced by infection and that irregular food supply increases pathogen load.


Assuntos
Alcaloides/biossíntese , Besouros/microbiologia , Controle de Insetos , Nosema/fisiologia , Controle Biológico de Vetores , Animais , Besouros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia
4.
J Invertebr Pathol ; 172: 107353, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179087

RESUMO

Nosema adaliae, a microsporidian pathogen described from the two-spotted lady beetle, Adalia bipunctata L., delays larval development when A. bipunctata is reared under laboratory conditions at 25 °C. In nature, lady beetles often experience a wide range of environmental temperatures, but little is known regarding the effects of microsporidian pathogens on lady beetles when they are reared at higher and lower temperatures. In this study, the effects of elevated rearing temperatures and microsporidiosis were observed on larval development time and mortality, sex ratios, alkaloid content (adaline and adalinine), and adult morphometrics. Uninfected larvae (24 h-old) were provided either an uninfected or N. adaliae-infected conspecific egg and subsequently reared at three temperatures (25 °C, 27.5 °C or 30 °C). After the egg was eaten, larvae were provided a diet of green peach aphids and their development was recorded daily. Following eclosion, a subsample of adults were photographed for microscopic measurements and reflex-fluid was collected for alkaloid analysis using gas chromatography-mass spectrometry. Afterwards, all individuals were examined to determine the number that had become infected, and the same subsample was used to assess the severity of infection. Development time was delayed significantly for larvae that consumed a N. adaliae-infected egg, and infected larvae took significantly longer to develop at 25 °C than at 27.5 °C or 30 °C. No differences were observed for larval mortality or sex ratios. The relative proportion of adaline increased when larvae were reared at 30 °C, but adaline concentration was not affected by the pathogen, N. adaliae. Adults reared at 25 °C had larger body measurements when compared to those reared at 27.5 °C and 30 °C. Overall, adults that had eaten a N. adaliae-infected A. bipunctata egg as larvae had similar body measurements to those that ate an uninfected egg. When comparing male and female measurements, a significant interaction between infection status, temperature and sex was observed for elytra length and head capsule width only. These measurements were similar for uninfected and N. adaliae-infected females across all temperatures. However, when reared at 25 °C, uninfected males had significantly smaller elytra and head capsules than did infected males; but when reared at 30 °C, no significant difference was observed for these measurements. Both percent infection and average spore count decreased at 27.5 °C and 30 °C. These results suggest that temperatures above 25 °C have a mitigating effect against N. adaliae in A. bipunctata.


Assuntos
Alcaloides/biossíntese , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Besouros , Nosema/fisiologia , Piperidinas/metabolismo , Temperatura , Animais , Besouros/crescimento & desenvolvimento , Besouros/metabolismo , Besouros/microbiologia , Feminino , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/microbiologia , Masculino , Controle Biológico de Vetores , Razão de Masculinidade
5.
J Invertebr Pathol ; 161: 7-13, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30580010

RESUMO

Two species of microsporidia have been described from lady beetles that are commercially available for biological control: Nosema adaliae from the two-spotted lady beetle, Adalia bipunctata L., and Tubulinosema hippodamiae from the convergent lady beetle, Hippodamia convergens Guérin-Méneville. These pathogens delay larval development under controlled conditions, but little is known regarding the effects that microsporidia cause when their hosts are subjected to stressful conditions that are often experienced in nature. In this study, the combined effects of microsporidiosis (N. adaliae on A. bipunctata and T. hippodamiae on H. convergens) and irregular food availability were observed on host fitness (larval development and mortality, sex ratios, and adult morphometrics). For each beetle species, 24 h-old larvae were provided either an uninfected or microsporidia-infected conspecific egg. After the egg was eaten, some larvae were provided an abundance of aphids daily, whereas others were provided aphids on an irregular basis. Development was delayed significantly for larvae that consumed a microsporidia-infected egg, and for those fed irregularly. For A. bipunctata, a significant interaction was observed between infection status and food availability. This suggests that N. adaliae-infected A. bipunctata larvae that have an irregular supply of aphids undergo further developmental delays than those with a generous food supply. This interaction was not observed for T. hippodamiae-infected H. convergens. For both species, larval mortality and sex ratios did not differ significantly, regardless of infection status or food availability. Adults that were fed daily as larvae were significantly larger than those fed irregularly. However, the elytra of N. adaliae-infected A. bipunctata were significantly larger than the elytra of their uninfected cohorts, and T. hippodamiae-infected H. convergens had wider pronota and head capsules than uninfected H. convergens. Because N. adaliae and T. hippodamiae prolong larval development of their respective hosts under controlled conditions, one would expect these pathogens to cause more profound effects when their hosts experience stressful conditions. The results from this study indicate that this was the case for A. bipunctata, but not for H. convergens.


Assuntos
Besouros/crescimento & desenvolvimento , Microsporídios , Microsporidiose , Nosema , Animais , Agentes de Controle Biológico , Besouros/microbiologia , Comportamento Alimentar , Larva/crescimento & desenvolvimento , Larva/microbiologia , Microsporidiose/microbiologia
6.
Clin Obes ; 7(6): 368-376, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28871633

RESUMO

Aintree LOSS is a community-based, multidisciplinary weight management programme for patients with severe and complex obesity, focusing on a flexible and individualized service with follow-up for up to 2 years. We evaluated all 2472 patients referred to the service between October 2009 and 2013. Demographic data were recorded at baseline, with the Index of Multiple Deprivation (IMD) used to measure socioeconomic deprivation. Weight was recorded at each visit. Mean body mass index at baseline was 45.6 (standard deviation 6.8), and 58.9% of patients lived in areas in the most deprived decile nationally. Of 2315 appropriate referrals, 1249 (55.1%) attended >2 visits; mean final weight loss was 3.50 ± 8.55 kg, and 24.1% achieved ≥5% weight loss. Of the patients, 754 (33.3%) attended for over 6 months; mean final weight loss was 4.94 ± 10 kg, and 34% achieved 5% weight loss. Multivariate logistic regression analysis showed increasing age, residence in a less deprived area and sleep apnoea to be independently associated with attendance for >6 months, and there was a linear relationship between 6-month attendance and deprivation quintile. Year-on-year analyses showed improvement in engagement over time, coinciding with efforts to improve access to the service. This work shows a multidisciplinary, community-based weight loss programme prioritizing a fully flexible and individualized approach functioning effectively in real-world practice. Maintaining engagement remains a challenge in weight loss programmes, and our results suggest younger patients living in areas with greater deprivation should be a target for efforts to improve engagement.


Assuntos
Obesidade/psicologia , Participação do Paciente/psicologia , Programas de Redução de Peso/métodos , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Cooperação do Paciente , Características de Residência , Redução de Peso , Adulto Jovem
7.
Int J Obes (Lond) ; 41(6): 853-865, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28077863

RESUMO

Overfeeding experiments, in which we impose short-term positive energy balance, help unravel the cellular, physiological and behavioural adaptations to nutrient excess. These studies mimic longer-term mismatched energy expenditure and intake. There is considerable inter-individual heterogeneity in the magnitude of weight gain when exposed to similar relative caloric excess reflecting variable activation of compensatory adaptive mechanisms. Significantly, given similar relative weight gain, individuals may be protected from/predisposed to metabolic complications (insulin resistance, dyslipidaemia, hypertension), non-alcoholic fatty liver disease and cardiovascular disease. Similar mechanistic considerations underpinning the heterogeneity of overfeeding responses are pertinent in understanding emerging metabolic phenotypes, for example, metabolically unhealthy normal weight and metabolically healthy obesity. Intrinsic and extrinsic factors modulate individuals' overfeeding response: intrinsic factors include gender/hormonal status, genetic/ethnic background, baseline metabolic health and cardiorespiratory fitness; extrinsic factors include macronutrient (fat vs carbohydrate) content, fat/carbohydrate composition and overfeeding pattern. Subcutaneous adipose tissue (SAT) analysis, coupled with metabolic assessment, with overfeeding have revealed how SAT remodels to accommodate excess nutrients. SAT remodelling occurs either by hyperplasia (increased adipocyte number) or by hypertrophy (increased adipocyte size). Biological responses of SAT also govern the extent of ectopic (visceral/liver) triglyceride deposition. Body composition analysis by DEXA/MRI (dual energy X-ray absorptiometry/magnetic resonance imaging) have determined the relative expansion of SAT (including abdominal/gluteofemoral SAT) vs ectopic fat with overfeeding. Such studies have contributed to the adipose expandability hypothesis whereby SAT has a finite capacity to expand (governed by intrinsic biological characteristics), and once capacity is exceeded ectopic triglyceride deposition occurs. The potential for SAT expandability confers protection from/predisposes to the adverse metabolic responses to overfeeding. The concept of a personal fat threshold suggests a large inter-individual variation in SAT capacity with ectopic depot expansion/metabolic decompensation once one's own threshold is exceeded. This review summarises insight gained from overfeeding studies regarding susceptibility to obesity and related complications with nutrient excess.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Suscetibilidade a Doenças , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/etiologia , Hipernutrição/complicações , Gordura Subcutânea/patologia , Absorciometria de Fóton , Adiposidade , Composição Corporal , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Humanos , Resistência à Insulina/fisiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Hipernutrição/metabolismo , Hipernutrição/fisiopatologia , Gordura Subcutânea/diagnóstico por imagem , Triglicerídeos/metabolismo , Aumento de Peso/fisiologia
8.
Phys Rev Lett ; 119(26): 261802, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29328732

RESUMO

We construct asymptotically safe extensions of the standard model by adding gauged vectorlike fermions. Using large number-of-flavor techniques we argue that all gauge couplings, including the hypercharge and, under certain conditions, the Higgs coupling, can achieve an interacting ultraviolet fixed point.

9.
J Clin Neurosci ; 33: 198-204, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27469409

RESUMO

Patients with voltage-gated potassium channel (VGKC)-complex antibodies are increasingly recognized as having central, peripheral or combined phenotypes. With increasing awareness, more patients are tested and the clinical spectrum is expanding. Consequently, clinicians may be uncertain as to which patients should or should not be tested. Previous studies have identified common clinical features, but none has looked at the usefulness of these in predicting seropositive disease. We conducted a case-control study of patients tested for VGKC-complex antibodies over 10years at a regional tertiary neurology centre determining which clinical/biochemical features were associated with antibody-positive disease. We found a marked increase in the numbers tested, although the percentage positive remained low. Antibody titre was highest in central disease (p<0.001). Time from presentation to testing was shorter in those with VGKC-disease (p=0.01). Seizures were present in 11 (69%) of those with VGKC-disease versus three (18%) without (odds ratio [OR] 10.3, 95% confidence interval [CI]: 2.0-52.7, p=0.005). There was an inverse correlation between the antibody titre and serum sodium. A multivariate model selected seizures and hyponatraemia as predictive of VGKC disease (sensitivity 75% and specificity 82%); faciobrachial dystonic movements were specific but insensitive. Interestingly serum alkaline phosphatase was higher in those with VGKC-disease (p=0.016) and highest in those with peripheral disease (p=0.015). An ALP>70u/L was strongly associated with antibody positivity (OR 4.11 95% CI: 1.43-11.8, p=0.007) with a sensitivity of 74.2%. The presence of seizures, faciobrachial movements, and hyponatraemia should raise suspicion of VGKC-disease; alkaline phosphatase may represent a novel biomarker, particularly in those with peripheral disease.


Assuntos
Autoanticorpos/análise , Canais de Potássio de Abertura Dependente da Tensão da Membrana/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Distonia/etiologia , Feminino , Humanos , Hiponatremia/etiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Convulsões/etiologia , Adulto Jovem
10.
Phys Rev Lett ; 117(2): 022002, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27447501

RESUMO

We investigate the recent evidence for a charged X(5568) meson as an exotic open-flavor tetraquark state sub[over ¯]d[over ¯] with J^{P}=0^{+}/1^{+} in the framework of QCD sum rules. We use the color antisymmetric [3[over ¯]_{c}]_{su}⊗[3_{c}]_{b[over ¯]d[over ¯]} tetraquark currents in both scalar and axial-vector channels to perform evaluations and numerical analyses. Our results imply that the X(5568) can be interpreted as both the scalar sub[over ¯]d[over ¯] tetraquark state and the axial-vector one, which are in good agreement with the experimental measurement. We also discuss the possible decay patterns of the X(5568) and suggest to search for its neutral partner in the radiative decay into B_{s}^{0}γ and B_{s}^{*}γ, which can be used to determine its spin-parity quantum numbers. Moreover, we predict its charmed partner state around 2.55 GeV with the quark content suc[over ¯]d[over ¯] and J^{P}=0^{+}/1^{+}.

11.
Phys Rev Lett ; 115(17): 172001, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26551105

RESUMO

Inspired by P(c)(4380) and P(c)(4450) recently observed by LHCb, a QCD sum rule investigation is performed, by which they can be identified as exotic hidden-charm pentaquarks composed of an anticharmed meson and a charmed baryon. Our results suggest that P(c)(4380) and P(c)(4450) have quantum numbers J(P)=3/2(-) and 5/2(+), respectively. Furthermore, two extra hidden-charm pentaqurks with configurations D̅Σ(c)(*) and D̅(*)Σ(c)(*) are predicted, which have spin-parity quantum numbers J(P)=3/2(-) and J(P)=5/2(+), respectively. As an important extension, the mass predictions of hidden-bottom pentaquarks are also given. Searches for these partners of P(c)(4380) and P(c)(4450) are especially accessible at future experiments like LHCb and BelleII.

12.
Obes Rev ; 16(3): 248-58, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25580667

RESUMO

Obesity is associated with a profound impairment in the ability to perform the basic physical activities required for everyday function. This impacts on quality of life and contributes to disability. Bariatric surgery leads to weight loss and metabolic improvements in severe obesity; however, less is known about its effect on physical functioning. This narrative review summarizes current evidence on the effect of bariatric surgery on this outcome with a consideration of the mechanisms involved. Nine longitudinal observational studies reporting objective measures of physical functioning were identified. Inclusion criteria, follow-up time and outcomes reported varied considerably between studies and sample sizes were small. They all showed a significant improvement in performance following surgery despite variations in baseline patient characteristics. Additionally, six studies were found in which subjects were subjected to exercise testing protocols. Performance of the test protocol improved in all. Where reported, peak oxygen uptake related to body weight improved; however, absolute values were either unchanged or decreased. In conclusion, observational evidence suggests that patients' physical functioning improves following bariatric surgery. More evidence is required regarding mechanisms involved; however, it may be due to improved efficiency in performing activities as opposed to absolute improvements in cardiorespiratory or muscle function.


Assuntos
Atividades Cotidianas/psicologia , Cirurgia Bariátrica , Obesidade Mórbida/fisiopatologia , Qualidade de Vida/psicologia , Redução de Peso , Medicina Baseada em Evidências , Humanos , Estudos Longitudinais , Obesidade Mórbida/psicologia , Obesidade Mórbida/cirurgia , Estudos Observacionais como Assunto , Resultado do Tratamento
13.
J Dairy Sci ; 98(3): 1759-71, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547297

RESUMO

Cooling systems used to reduce heat stress in dairy operations require high energy, water usage, or both. Steady increases in electricity costs and reduction of water availability and an increase in water usage regulations require evaluation of passive cooling systems to cool cows and reduce use of water and electricity. A study was conducted to evaluate the use of heat exchangers buried 25 cm below the surface as components in a conductive system for cooling cows. Six cows were housed in environmentally controlled rooms with tie-stall beds, which were equipped with a heat exchanger and filled with 25 cm of either sand or dried manure. Beds were connected to supply and return lines and individually controlled. Two beds (one per each kind of bedding material) constituted a control group (water off), and the other 4 (2 sand and 2 dried manure) used water at 7°C passing through the heat exchangers (water on). The experiment was divided in 2 periods of 40 d, and each period involved 3 repetitions of 3 different climates (hot and dry, thermo neutral, and hot and humid). Each cow was randomly assigned to a different treatment after each repetition was over. Sand bedding remained cooler than dried manure bedding in all environments and at all levels of cooling (water on or off). Bed temperatures were lower and heat flux higher during the bed treatment with sand and water on. We also detected a reduction in core body temperatures, respiration rates, rectal temperatures, and skin temperatures of those cows during the sand and water on treatment. Feed intake and milk yield numerically increased during the bed treatment with sand and water on for all climates. No major changes were observed in the lying time of cows or the composition of the milk produced. We conclude that use of heat exchangers is a viable adjunct to systems that employ fans, misters, and evaporative cooling methods to mitigate effects of heat stress on dairy cows. Sand was superior to dried manure as a bedding material in combination with heat exchangers.


Assuntos
Criação de Animais Domésticos , Bovinos/fisiologia , Indústria de Laticínios/economia , Indústria de Laticínios/métodos , Animais , Roupas de Cama, Mesa e Banho/veterinária , Temperatura Corporal , Ambiente Controlado , Feminino , Temperatura Alta , Lactação , Leite/economia , Distribuição Aleatória , Taxa Respiratória , Água
14.
Phys Rev Lett ; 112(17): 171602, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24836235

RESUMO

We consider the generation of dark matter mass via radiative electroweak symmetry breaking in an extension of the conformal standard model containing a singlet scalar field with a Higgs portal interaction. Generating the mass from a sequential process of radiative electroweak symmetry breaking followed by a conventional Higgs mechanism can account for less than 35% of the cosmological dark matter abundance for dark matter mass M(s)>80 GeV. However, in a dynamical approach where both Higgs and scalar singlet masses are generated via radiative electroweak symmetry breaking, we obtain much higher levels of dark matter abundance. At one-loop level we find abundances of 10%-100% with 106 GeV80 GeV detection region of the next generation XENON experiment.

15.
J Invertebr Pathol ; 115: 108-15, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24135414

RESUMO

The two-spotted lady beetle, Adalia bipunctata L., is a tree-dwelling lady beetle endemic to parts of Europe, Central Asia and North America that is commercially available for aphid control in Europe and North America. Lady beetles host a wide variety of symbionts including parasitoids, viruses, eugregarines, fungi, bacteria, nematodes and microsporidia. Four species of microsporidia have been described from lady beetles, and an undescribed microsporidium was recently isolated from local populations of A. bipunctata in Nova Scotia, Canada. In a previous study, this pathogen prolonged the development of A. bipunctata larvae but had no effect on adult fecundity, longevity or sex ratios. The objective of this study was to formally describe the microsporidium by means of its ultrastructure, tissue pathology and molecular characterization. All stages of the microsporidium were diplokaryotic and developed in direct contact with the host cell cytoplasm. Mature spores measured 4.25±0.09×1.82±0.03µm (SE, n=49, from micrographs) and fresh spores measured 6.10±0.06×3.01±0.05µm (±SE, n=60; range: 5.0-6.9×2.18-3.86µm). The polar filament was isofilar with 10-18 coils that were frequently arranged in a single row. The lamellar polaroplast was not typically visible and spores contained a relatively small posterior vacuole. Both the flight muscles and fat body were heavily infected and a large number of spores were observed within and between the cells of these tissues. The ovaries, developing oocytes, spermatocytes and accessory glands within the testes, midgut epithelium, Malpighian tubules, ileum, colon, and ventral nerve cord were also infected but not as heavily. Connective tissue near the cuticle and surrounding the trachea were lightly infected. The presence of spores in both the alimentary canal and ovaries (particularly within developing oocytes) suggests that the microsporidium can be transmitted per os (horizontally) and transovarially (vertically). Molecular analysis of the genome of the microsporidium described in this study was 97% similar to Nosema bombi and 96% similar to Nosema thomsoni, Nosema vespula and Nosema oulemae. Based on information gained during this study, we propose that the microsporidium in A. bipunctata be given the name Nosema adaliae sp. nov.


Assuntos
Besouros/microbiologia , Nosema/fisiologia , Nosema/ultraestrutura , Animais
16.
J Invertebr Pathol ; 114(1): 53-60, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23727346

RESUMO

Lacewing larvae are generalist predators that are commercially available for aphid control on a variety of crops in both Europe and North America. Although lacewings are known for their symbiotic association with yeasts and bacteria, there are few reports of microsporidia in these natural enemies. An undescribed microsporidium was found in Chrysoperla carnea (Stephens) during the routine examination of specimens that were obtained from a commercial insectary for biological pest control. The objective of this study was to describe the pathogen by means of ultrastructure, molecular characterization and tissue pathology. All stages of the microsporidium were diplokaryotic and developed in direct contact with the host cell cytoplasm. Merogony and sporogony were not observed. Mature spores measured 3.49±0.10×1.52±0.05µm and had an isofilar polar filament with 8-10 coils that were frequently arranged in a single row, although double rows were also observed. Spores contained a lamellar polaroplast and a relatively small and inconspicuous polar vacuole was observed in the posterior region of about half of the spores that were examined. Tubular structures, similar in appearance to those in Nosema granulosis were observed in both sporonts and in spores. A cluster of small tubules was also observed in the posterior region of some spores. Microsporidian spores were observed in cells of the proventriculus, diverticulum and in epithelial cells of the posterior midgut. The Malpighian tubules, ileum, and rectum were heavily infected. Spores were also observed in the fat body, peripheral region of the ganglia, within and between the flight muscles, and beneath the cuticle. Although the tissues adjacent to the ovaries were heavily infected, microsporidian spores were not observed within the developing eggs. Pathogen transmission was not studied directly because it was difficult to maintain microsporidia-infected C. carnea in the laboratory. The presence of microsporidian spores in the alimentary canal suggests that the pathogen is transmitted per os and horizontal transmission may occur when infected larvae or adults are cannibalized by uninfected larvae. Molecular analysis of the microsporidian genome showed that the pathogen described in this study was 99% similar to Nosema bombycis, N. furnacalis, N. granulosis and N. spodopterae. Based on information gained during this study, we propose that the microsporidium in C. carnea be given the name Nosema chrysoperlae sp. nov.


Assuntos
Insetos/microbiologia , Nosema/ultraestrutura , Controle Biológico de Vetores , Animais , DNA Fúngico/química , Genoma Fúngico , Insetos/crescimento & desenvolvimento , Larva/microbiologia , Nosema/genética , Nosema/isolamento & purificação , Análise de Sequência de DNA , Esporos Fúngicos/genética
17.
Phys Rev Lett ; 110(15): 151601, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25167247

RESUMO

The mechanism of radiative electroweak symmetry breaking occurs through loop corrections, and unlike conventional symmetry breaking where the Higgs mass is a parameter, the radiatively generated Higgs mass is dynamically predicted. Padé approximations and an averaging method are developed to extend the Higgs mass predictions in radiative electroweak symmetry breaking from five- to nine-loop order in the scalar sector of the standard model, resulting in an upper bound on the Higgs mass of 141 GeV. The mass predictions are well described by a geometric series behavior, converging to an asymptotic Higgs mass of 124 GeV consistent with the recent ATLAS and CMS Collaborations observations. Similarly, we find that the Higgs self-coupling converges to λ=0.23, which is significantly larger than its conventional symmetry breaking counterpart for a 124 GeV Higgs mass. In addition to this significant enhancement of the Higgs self-coupling and HH→HH scattering, we find that Higgs decays to gauge bosons are unaltered and the scattering processes WL(+)WL(+)→HH, ZLZL→HH are also enhanced, providing signals to distinguish conventional and radiative electroweak symmetry breaking mechanisms.

18.
J Invertebr Pathol ; 109(2): 223-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22138254

RESUMO

Two-spotted lady beetles, Adalia bipunctata L. are available for biological pest control in North America. Lady beetles are known to host microsporidia and although these pathogens are able to infect more than one host under laboratory conditions, little is known regarding the effects of more than one microsporidian pathogen on host fitness. In this study, egg cannibalism was used to examine the effects of the microsporidium Tubulinosema hippodamiae from Hippodamia convergens and an undescribed microsporidium from A. bipunctata (alone and in combination) on A. bipunctata host fitness (larval development and mortality, sex ratio, adult fecundity and longevity). Development was prolonged significantly for larvae that were infected with the undescribed microsporidium but T. hippodamiae had no effect and as a result, conclusions could not be made regarding the effects of both pathogens on larval development. The two microsporidia had no effect on sex ratios (1♀:1♂) or on adult fecundity and longevity. Spores were detected in the majority of smear preparations of individuals that were fed microsporidia-infected eggs and molecular analysis confirmed the identity of both pathogens in sampled individuals. T. hippodamiae spores were smaller than spores of the undescribed microsporidium (3.76±0.03×2.32±0.02 µm and 5.43±0.06×2.75±0.03 µm, respectively) and although the former stained less intensely than did those of latter, spores of the two pathogens are difficult to differentiate when examined by light microscopy alone. The ability of some microsporidia to infect more than one lady beetle host makes it difficult to conclude with certainty as to the number of species that are present in infected Adalia when specimens are examined solely by light microscopy.


Assuntos
Besouros/microbiologia , Inseticidas , Microsporídios/patogenicidade , Microsporidiose/veterinária , Controle Biológico de Vetores/métodos , Animais , Feminino , Fertilidade , Interações Hospedeiro-Patógeno , Transmissão Vertical de Doenças Infecciosas , Larva/microbiologia , Longevidade , Masculino , Microsporídios/fisiologia , Microsporidiose/fisiopatologia , Microsporidiose/transmissão , Óvulo/microbiologia , Razão de Masculinidade
19.
Appl Radiat Isot ; 68(7-8): 1540-2, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20018519

RESUMO

Activity measurements of (3)H were performed using the triple to double coincidence ratio method for the 2009 international comparison organized by the Bureau International des Poids et Mesures (BIPM). The activity obtained by using the FPGA (field programmable gate array) acquisition system and software event analysis was compared to that using MAC3 (Module d'Acquisition de Coincidences triples). Agreement to better than 0.4% was obtained. The stability of sources prepared in Ultima Gold, Ultima Gold LLT, Insta-Gel Plus and Optiphase "Hisafe"-3 over 140 days is presented.

20.
J Hum Evol ; 55(1): 179-85, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18396318

RESUMO

We report here on the isotopic analysis (carbon and nitrogen) of collagen extracted from a Neanderthal tooth and animal bone from the late Mousterian site of Jonzac (Charente-Maritime, France). This study was undertaken to test whether the isotopic evidence indicates that animal protein was the main source of dietary protein for this relatively late Neanderthal, as suggested by previous studies. This was of particular interest here because this is the first isotopic study of a relatively late Neanderthal associated with Mousterian of Acheulian Tradition (MTA, dating to approximately 55,000 to 40,000 BP) technology. We found that the Jonzac Neanderthal had isotopic values consistent with a diet in which the main protein sources were large herbivores, particularly bovids and horses. We also found evidence of different dietary niches between the Neanderthal and a hyena at the site, with the hyena consuming mainly reindeer.


Assuntos
Colágeno/análise , Proteínas Alimentares/análise , Comportamento Alimentar , Hominidae/fisiologia , Animais , Osso e Ossos/química , Isótopos de Carbono/análise , França , Humanos , Isótopos de Nitrogênio/análise , Dente/química
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