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1.
Mol Pharm ; 19(7): 2549-2563, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35583476

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by increased levels of desmoplasia that contribute to reduced drug delivery and poor treatment outcomes. In PDAC, the stromal content can account for up to 90% of the total tumor volume. The complex interplay between stromal components, including pancreatic cancer-associated fibroblasts (PCAFs), and PDAC cells in the tumor microenvironment has a significant impact on the prognoses and thus needs to be recapitulated in vitro when evaluating various treatment strategies. This study is a systematic evaluation of photodynamic therapy (PDT) in 3D heterotypic coculture models of PDAC with varying ratios of patient-derived PCAFs that simulate heterogeneous PDAC tumors with increasing stromal content. The efficacy of antibody-targeted PDT (photoimmunotherapy; PIT) using cetuximab (a clinically approved anti-EGFR antibody) photoimmunoconjugates (PICs) of a benzoporphyrin derivative (BPD) is contrasted with that of liposomal BPD (Visudyne), which is currently in clinical trials for PDT of PDAC. We demonstrate that both Visudyne-PDT and PIT were effective in heterotypic PDAC 3D spheroids with a low stromal content. However, as the stromal content increases above 50% in the 3D spheroids, the efficacy of Visudyne-PDT is reduced by up to 10-fold, while PIT retains its efficacy. PIT was found to be 10-, 19-, and 14-fold more phototoxic in spheroids with 50, 75, and 90% PCAFs, respectively, as compared to Visudyne-PDT. This marked difference in efficacy is attributed to the ability of PICs to penetrate and distribute homogeneously within spheroids with a higher stromal content and the mechanistically different modes of action of the two formulations. This study thus demonstrates how the stromal content in PDAC spheroids directly impacts their responsiveness to PDT and proposes PIT to be a highly suited treatment option for desmoplastic tumors with particularly high degrees of stromal content.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Fotoquimioterapia , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Microambiente Tumoral , Verteporfina , Neoplasias Pancreáticas
2.
Biol Lett ; 18(8): 20220223, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35975628

RESUMEN

Sleep is one of the few truly ubiquitous animal behaviours, and though many animals spend enormous periods of time asleep, we have only begun to understand the consequences of sleep disturbances. In humans, sleep is crucial for effective communication. Birds are classic models for understanding the evolution and mechanisms of human language and speech. Bird vocalizations are remarkably diverse, critical, fitness-related behaviours, and the way sleep affects vocalizations is likely similarly varied. However, research on the effects of sleep disturbances on avian vocalizations is shockingly scarce. Consequently, there is a critical gap in our understanding of the extent to which sleep disturbances disrupt communication. Here, we argue that sleep disturbances are likely to affect all birds' vocal performance by interfering with motivation, memory consolidation and vocal maintenance. Further, we suggest that quality sleep is likely essential when learning new vocalizations and that sleep disturbances will have especially strong effects on learned vocalizations. Finally, we advocate for future research to address gaps in our understanding of how sleep influences vocal learning and performance in birds.


Asunto(s)
Sueño , Pájaros Cantores , Vocalización Animal , Animales , Aves , Aprendizaje , Sueño/fisiología
3.
Prev Med ; 156: 106960, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35065979

RESUMEN

The global confrontation with COVID-19 has not only diverted current healthcare resources to deal with the infection but has also resulted in increased resources in the areas of testing and screening, as well as educating most of the global public of the benefits of vaccination. When the COVID-19 pandemic eventually recedes, the opportunity must not be missed to ensure that these newly created resources are maintained and redeployed for use in testing and immunisation against other vaccine-preventable infectious diseases. A notable example is infection by human papillomavirus (HPV), the commonest sexually transmitted human virus and the leading cause of a variety of cancers in both men and women, such as cervical, head and neck, anal, vaginal, vulvar and penile cancers. The most important is cervical cancer, the objective of the global elimination goals targeting the vaccination of young female and male adolescents, screening all women and treatment of all infected women. As the campaigns to control SARS-CoV-2, the eradication of HPV-induced cancers also relies on effective prevention and control programs. The lessons learned and the technical, logistical and human resources which have been established to combat COVID-19 by vaccination and testing must be applied to the eradication of other infections which affect the global population. This commentary summarizes the opportunities that the COVID-19 pandemic has created for HPV prevention and control, lists the already available tools for HPV control, and emphasizes the potential public health threats amidst the ongoing COVID-19 pandemic.


Asunto(s)
Alphapapillomavirus , COVID-19 , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Neoplasias del Cuello Uterino , Adolescente , COVID-19/prevención & control , Femenino , Humanos , Masculino , Pandemias/prevención & control , Papillomaviridae , Infecciones por Papillomavirus/epidemiología , Vacunas contra Papillomavirus/uso terapéutico , SARS-CoV-2 , Neoplasias del Cuello Uterino/diagnóstico , Vacunación
4.
Br J Cancer ; 124(4): 831-841, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33257839

RESUMEN

BACKGROUND: The host adaptive immune response helps determine which cervical HPV infections persist and progress to precancer and cancer, and systematic characterisation of T-cell infiltration would help inform key steps in cervical carcinogenesis. METHODS: A systematic review and meta-analysis were conducted of infiltrating T-cells in normal cervix, low-grade lesions, high-grade lesions, and invasive cancers including epithelial, stromal, and total tissue and the following markers: CD3, CD4, CD8, FoxP3, CD25, and the CD4:CD8 ratio. An additional qualitative review summarised longitudinal data on associations between infiltrating T-cells and cervical disease persistence, regression, progression, or prognosis. RESULTS: There were fewer CD3+, CD4+, and CD8+ cells in cervical lesions and more cells in cancers compared to normal epithelium. FoxP3 and CD25+ regulatory T-cell infiltration is high in persistent and precancerous lesions, and longitudinal data show improved outcomes with lower regulatory T-cell levels. CONCLUSIONS: Successful immune evasion may reduce T-cell infiltration in HPV infected and precancerous epithelium, while invasive cancers are highly immunogenic, and regulatory T-cell infiltration increases with cervical disease progression. Understanding these factors may have prognostic value and could aid in novel treatment development and clinical guidelines, but published data are highly heterogeneous and leave important gaps to be filled by future studies.


Asunto(s)
Linfocitos Infiltrantes de Tumor/inmunología , Infecciones por Papillomavirus/inmunología , Linfocitos T/inmunología , Neoplasias del Cuello Uterino/inmunología , Carcinogénesis/inmunología , Carcinogénesis/patología , Femenino , Humanos , Linfocitos Infiltrantes de Tumor/patología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/patología , Linfocitos T/patología , Neoplasias del Cuello Uterino/patología
5.
Prev Med ; 144: 106321, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33678229

RESUMEN

Prophylactic HPV vaccination has been a great public health success. For >20 years, clinical trials were conducted with the 2-, 4-, and/or 9-valent vaccines in young-adult females, mid-adult women, males, and adolescents. In all studies, the vaccines were highly efficacious, immunogenic, and well tolerated. Following vaccine licensure and utilization in national vaccine programs globally (real-world settings primarily in high income countries), numerous studies demonstrated that the vaccines continue to have an excellent safety profile and have dramatically reduced the incidence of genital warts, HPV vaccine-type prevalence, and precancerous lesions. Thirty-eight clinical trials with the currently licensed HPV vaccines are ongoing. Key questions being addressed in new trials include: efficacy against persistent infection and immunogenicity of a 1-dose regimen; efficacy of 3 doses in 20-45-year-old females; use in postpartum women and immunocompromised individuals (HIV, liver and kidney transplants); dose sparing via intradermal administration; use in combination with a PD1 monoclonal antibody in patients with cervical cancer; impact on recurrent disease in women undergoing cervical conization; persistence of protection; and use to prevent oropharyngeal cancer. Additional clinical research that should be conducted includes: long-term follow-up, particularly of 1- and 2-dose regimens; further evaluation of flexible 2-dose regimens; immunogenicity of 1- or 2-dose regimens in persons ≥15 years old and immunocompromised populations; safety and immunogenicity of 1 or 2 doses in children <9 years old; assessment of the vaccine in the prevention of transmission; interchangeability with newer HPV vaccines; additional concomitant use studies; and prevention of penile cancer and recurrent respiratory papillomatosis.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Infecciones del Sistema Respiratorio , Neoplasias del Cuello Uterino , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Papillomavirus/prevención & control , Salud Pública , Neoplasias del Cuello Uterino/prevención & control , Adulto Joven
6.
Environ Manage ; 66(1): 30-41, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32318754

RESUMEN

Cat ownership is increasing globally, representing a growing threat to urban wildlife. Although some cities have policies and strategies for managing owned cats, the companionship value placed on cats makes such management contentious. Prioritizing cat management in urban residential zones adjacent to large significant ecological areas (SEAs; areas designated on the basis of representativeness, threat status or rarity, diversity, connectedness, or uniqueness) could maximize return on management effort. Residents in these areas may place a relatively higher value on nature than residents in suburbs with minimal or no SEAs, and therefore may be comparatively more likely to perceive cats' wildlife impacts as important. We used a quantitative survey to compare SEA and non-SEA suburbs' residents' attitudes towards cat impacts and management in Tamaki Makaurau-Auckland, Aotearoa-New Zealand. Participants were asked to rate the importance of different feral and owned cat impacts, the importance of feral-cat control in different locations, and various ownership behaviors in terms of acceptability and best practice. SEA suburb residents placed more importance on wildlife predation impacts of feral cats and were more likely to regard 24-h cat confinement as best practice than non-SEA suburb residents. However, we also found that cat ownership and youth were negatively associated with perception of cat impacts, and owners were less likely to accept belled collars and cat confinement than nonowners. Therefore, although targeting SEA adjacent areas for cat management holds promise for reducing resident contention, proximity to such areas is a relatively minor influence for cat owners.


Asunto(s)
Actitud , Propiedad , Animales , Animales Salvajes , Gatos , Ciudades , Nueva Zelanda
7.
J Infect Dis ; 219(1): 41-49, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30085139

RESUMEN

Background: There are limited data regarding the duration of immunity induced by different human papillomavirus (HPV) vaccination schedules and the immunogenicity of a booster dose of both bivalent HPV vaccine (bHPV) or quadrivalent HPV vaccine (qHPV). Methods: Follow-up of a nonrandomized clinical trial to evaluate the 5-year antibody persistence of the bHPV in girls (age, 9-10 years) and women (age, 18-24 years). Noninferiority of the 2-dose versus 3-dose schedule among girls was evaluated at months 54 (n = 639) and 64 (n = 990). Girls vaccinated with a 2-dose schedule of bHPV or qHPV received a booster dose of either vaccine at month 61. Immunogenicity was measured using a virus-like particle-based enzyme-linked immunosorbent assay. Geometric mean titers (GMTs) for HPV16/18 were estimated after stratification by vaccination schedule and age group. Results: At months 54 and 64, the 2-dose schedule remained noninferior to the 3-dose schedule. GMTs remained above natural infection levels across all age groups up to 64 months. After the booster, anti-HPV16/18 GMTs increased exponentially with the same pattern, regardless of vaccine administered. No safety concerns were identified with the booster dose. Conclusions: A 2-dose schedule is highly immunogenic in girls, suggesting a high immune memory. Thus, a booster dose is likely to be unprofitable, considering the low global immunization coverage. Clinical Trials Registration: NCT01717118.


Asunto(s)
Vacuna Tetravalente Recombinante contra el Virus del Papiloma Humano Tipos 6, 11 , 16, 18/inmunología , Inmunización Secundaria , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/inmunología , Vacunación , Adolescente , Anticuerpos Antivirales/sangre , Niño , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Vacuna Tetravalente Recombinante contra el Virus del Papiloma Humano Tipos 6, 11 , 16, 18/administración & dosificación , Papillomavirus Humano 16/inmunología , Papillomavirus Humano 18/inmunología , Humanos , Esquemas de Inmunización , Ensayos Clínicos Controlados no Aleatorios como Asunto , Infecciones por Papillomavirus/sangre , Infecciones por Papillomavirus/inmunología , Vacunas contra Papillomavirus/administración & dosificación , Vacunas contra Papillomavirus/sangre , Adulto Joven
8.
Gen Comp Endocrinol ; 272: 1-8, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30419229

RESUMEN

Handling of avian study species is common in ecological research, yet few studies account for the impact of handling in nestlings where exposure to stress may result in negative lifetime fitness consequences. As a result, our understanding of stress reactivity in free-living avian young is limited. In this study we examined the cumulative impact of three levels of research-relevant handling (control, daily and every three days) on the development of the stress response, growth and condition of semi-precocial seabird chicks from near-hatching to near-fledging. By measuring corticosterone concentrations in plasma, we found that mottled petrel (Pterodroma inexpectata) chicks were capable of mounting a stress response comparable to adults from near-hatching. There were no differences in plasma corticosterone concentrations in initial samples (<4 min) between groups at six weeks of age, though by 12 weeks of age plasma corticosterone concentrations in initial samples collected from chicks handled daily were lower than chicks that were handled once every three days, and from control chicks. Corticosterone responses to handling were lower in chicks handled daily at six and 12 weeks of age when compared to other handling groups. Handling chicks daily or every three days had no negative effect on the growth or condition of chicks when compared to control chicks. These findings indicate that daily handling results in chicks became accustomed to handling, with no evidence that regular handling was detrimental to mottled petrel chicks. However, given the unique life-history characteristics of mottled petrels relative to closely related species, we caution that this finding may be species-specific, and wider testing is recommended.


Asunto(s)
Corticosterona/sangre , Estrés Fisiológico/fisiología , Animales , Pollos , Femenino , Manejo Psicológico
9.
Proc Natl Acad Sci U S A ; 112(20): E2648-57, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25941361

RESUMEN

Food availability is a primary driver of avian population regulation. However, few studies have considered the effects of what is essentially a massive supplementary feeding experiment: the practice of wild bird feeding. Bird feeding has been posited as an important factor influencing the structure of bird communities, especially in urban areas, although experimental evidence to support this is almost entirely lacking. We carried out an 18-mo experimental feeding study at 23 residential properties to investigate the effects of bird feeding on local urban avian assemblages. Our feeding regime was based on predominant urban feeding practices in our region. We used monthly bird surveys to compare avian community composition, species richness, and the densities of local species at feeding and nonfeeding properties. Avian community structure diverged at feeding properties and five of the commonest garden bird species were affected by the experimental feeding regime. Introduced birds particularly benefitted, with dramatic increases observed in the abundances of house sparrow (Passer domesticus) and spotted dove (Streptopelia chinensis) in particular. We also found evidence of a negative effect on the abundance of a native insectivore, the grey warbler (Gerygone igata). Almost all of the observed changes did not persist once feeding had ceased. Our study directly demonstrates that the human pastime of bird feeding substantially contributes to the structure of avian community in urban areas, potentially altering the balance between native and introduced species.


Asunto(s)
Biota , Aves/fisiología , Ciudades , Métodos de Alimentación/veterinaria , Análisis de Varianza , Animales , Humanos , Especies Introducidas , Nueva Zelanda , Densidad de Población
11.
Glob Chang Biol ; 20(9): 2800-14, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24446429

RESUMEN

Climate change may facilitate alien species invasion into new areas, particularly for species from warm native ranges introduced into areas currently marginal for temperature. Although conclusions from modelling approaches and experimental studies are generally similar, combining the two approaches has rarely occurred. The aim of this study was to validate species distribution models by conducting field trials in sites of differing suitability as predicted by the models, thus increasing confidence in their ability to assess invasion risk. Three recently naturalized alien plants in New Zealand were used as study species (Archontophoenix cunninghamiana, Psidium guajava and Schefflera actinophylla): they originate from warm native ranges, are woody bird-dispersed species and of concern as potential weeds. Seedlings were grown in six sites across the country, differing both in climate and suitability (as predicted by the species distribution models). Seedling growth and survival were recorded over two summers and one or two winter seasons, and temperature and precipitation were monitored hourly at each site. Additionally, alien seedling performances were compared to those of closely related native species (Rhopalostylis sapida, Lophomyrtus bullata and Schefflera digitata). Furthermore, half of the seedlings were sprayed with pesticide, to investigate whether enemy release may influence performance. The results showed large differences in growth and survival of the alien species among the six sites. In the more suitable sites, performance was frequently higher compared to the native species. Leaf damage from invertebrate herbivory was low for both alien and native seedlings, with little evidence that the alien species should have an advantage over the native species because of enemy release. Correlations between performance in the field and predicted suitability of species distribution models were generally high. The projected increase in minimum temperature and reduced frosts with climate change may provide more suitable habitats and enable the spread of these species.


Asunto(s)
Araliaceae/crecimiento & desarrollo , Arecaceae/crecimiento & desarrollo , Cambio Climático , Especies Introducidas , Modelos Biológicos , Psidium/crecimiento & desarrollo , Demografía , Análisis Factorial , Nueva Zelanda , Plaguicidas/toxicidad , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo
12.
J Pathol ; 231(3): 354-66, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23913724

RESUMEN

In cervical carcinomas, high-risk human papillomavirus (HR-HPV) may be integrated into host chromosomes or remain extra-chromosomal (episomal). We used the W12 cervical keratinocyte model to investigate the effects of HPV16 early gene depletion on in vitro cervical carcinogenesis pathways, particularly effects shared by cells with episomal versus integrated HPV16 DNA. Importantly, we were able to study the specific cellular consequences of viral gene depletion by using short interfering RNAs known not to cause phenotypic or transcriptional off-target effects in keratinocytes. We found that while cervical neoplastic progression in vitro was characterized by dynamic changes in HPV16 transcript levels, viral early gene expression was required for cell survival at all stages of carcinogenesis, regardless of viral physical state, levels of early gene expression or histology in organotypic tissue culture. Moreover, HPV16 early gene depletion induced changes in host gene expression that were common to both episome-containing and integrant-containing cells. In particular, we observed up-regulation of autophagy genes, associated with enrichment of senescence and innate immune-response pathways, including the senescence-associated secretory phenotype (SASP). In keeping with these observations, HPV16 early gene depletion induced autophagy in both episome-containing and integrant-containing W12 cells, as evidenced by the appearance of autophagosomes, punctate expression of the autophagy marker LC3, conversion of LC3B-I to LC3B-II, and reduced levels of the autophagy substrate p62. Consistent with the reported association between autophagy and senescence pathways, HPV16 early gene depletion induced expression of the senescence marker beta-galactosidase and increased secretion of the SASP-related protein IGFBP3. Together, these data indicate that depleting HR-HPV early genes would be of potential therapeutic benefit in all cervical carcinogenesis pathways, regardless of viral physical state. In addition, the senescence/SASP response associated with autophagy induction may promote beneficial immune effects in bystander cells.


Asunto(s)
Autofagia , Transformación Celular Viral/genética , Senescencia Celular , Papillomavirus Humano 16/genética , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Autofagia/genética , Línea Celular Tumoral , Senescencia Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Regulación Viral de la Expresión Génica , Humanos , Proteínas Oncogénicas Virales/genética , Proteínas E7 de Papillomavirus/genética , Infecciones por Papillomavirus/complicaciones , Fenotipo , Plásmidos , Interferencia de ARN , ARN Mensajero/metabolismo , ARN Viral/metabolismo , Proteínas Represoras/genética , Factores de Tiempo , Transfección , Neoplasias del Cuello Uterino/genética , Integración Viral
13.
Oecologia ; 176(1): 117-27, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24989119

RESUMEN

Although selection by herbivores for increased feeding deterrence in hostplants is well documented, selection for increased oviposition deterrence is rarely examined. We investigated chemical mediation of oviposition by the parsnip webworm (Depressaria pastinacella) on its principal hostplant Pastinaca sativa to determine whether ovipositing adults choose hostplants based on larval suitability and whether hostplants experience selection for increased oviposition deterrence. Webworms consume floral tissues and florivory selects for increased feeding deterrents; moths, however, oviposit on leaves of pre-bolting plants. Exclusive use of different plant parts for oviposition and larval feeding suggests oviposition should select for increased foliar deterrents. Recent webworm colonization of New Zealand (NZ) allowed us to assess phenotypic changes in foliar chemicals in response to webworm oviposition. In a common garden experiment, we compared NZ populations with and without a history of infestation from 2004 to 2006 for changes in leaf chemistry in response to oviposition. Three leaf volatiles, cis- and trans-ocimene, and ß-farnesene, elicit strong responses in female moth antennae; these compounds were negatively associated with oviposition and are likely oviposition deterrents. Leaf ß-farnesene was positively correlated with floral furanocoumarins that deter florivory; greater oviposition on plants with low floral furanocoumarins indicates that moths preferentially oviposit on parsnips most suitable for larval growth. Unlike florivory, high oviposition on leaves did not lower plant fitness, consistent with the fact that NZ parsnip foliar chemistry was unaffected by 3-6 years of webworm infestation. Thus, in this system, selection by ovipositing moths on foliar chemistry is weaker than selection by larvae on floral chemistry.


Asunto(s)
Evolución Biológica , Herbivoria/fisiología , Especies Introducidas , Mariposas Nocturnas/fisiología , Oviposición/fisiología , Pastinaca/parasitología , Animales , Cromatografía de Gases , Furocumarinas/metabolismo , Illinois , Nueva Zelanda , Hojas de la Planta/metabolismo , Sesquiterpenos/metabolismo
14.
Clin Microbiol Rev ; 25(2): 215-22, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22491770

RESUMEN

Human papillomavirus (HPV) infection of the genital tract is common in young sexually active individuals, the majority of whom clear the infection without overt clinical disease. Most of those who do develop benign lesions eventually mount an effective cell-mediated immune (CMI) response, and the lesions regress. Regression of anogenital warts is accompanied histologically by a CD4(+) T cell-dominated Th1 response; animal models support this and provide evidence that the response is modulated by antigen-specific CD4(+) T cell-dependent mechanisms. Failure to develop an effective CMI response to clear or control infection results in persistent infection and, in the case of the oncogenic HPVs, an increased probability of progression to high-grade intraepithelial neoplasia and invasive carcinoma. Effective evasion of innate immune recognition seems to be the hallmark of HPV infections. The viral infectious cycle is exclusively intraepithelial: there is no viremia and no virus-induced cytolysis or cell death, and viral replication and release are not associated with inflammation. HPV globally downregulates the innate immune signaling pathways in the infected keratinocyte. Proinflammatory cytokines, particularly the type I interferons, are not released, and the signals for Langerhans cell (LC) activation and migration, together with recruitment of stromal dendritic cells and macrophages, are either not present or inadequate. This immune ignorance results in chronic infections that persist over weeks and months. Progression to high-grade intraepithelial neoplasia with concomitant upregulation of the E6 and E7 oncoproteins is associated with further deregulation of immunologically relevant molecules, particularly chemotactic chemokines and their receptors, on keratinocytes and endothelial cells of the underlying microvasculature, limiting or preventing the ingress of cytotoxic effectors into the lesions. Recent evidence suggests that HPV infection of basal keratinocytes requires epithelial wounding followed by the reepithelization of wound healing. The wound exudate that results provides a mechanistic explanation for the protection offered by serum neutralizing antibody generated by HPV L1 virus-like particle (VLP) vaccines.


Asunto(s)
Células Epiteliales/virología , Interacciones Huésped-Patógeno , Papillomaviridae/fisiología , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Humanos , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/inmunología
16.
J Exp Zool A Ecol Integr Physiol ; 341(7): 733-742, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38651561

RESUMEN

Vocalization is an important communication tool that can reflect many aspects of an individual's internal and external condition. This is especially true for birds. Previous research has shown that bird calls and songs change in response to a variety of potential stressors, although the extent and direction of the changes depend on the nature of the stressor and the environment. Circulating glucocorticoids, such as corticosterone, often increase in response to stressors and mediate some of the observed changes via alterations of the individual's physiological state. Acute elevations of corticosterone often occur as a physiological response to short-term stressors; however, the effects of this elevation on adult vocalizations have not been well documented. Here, we experimentally elevated corticosterone at two different levels using a noninvasive method and examined the effects on the vocal communication of male and female adult common mynas (Acridotheres tristis). Corticosterone elevation temporarily increased song output and some measures of song complexity, while call output decreased. These effects were dosage dependent (higher corticosterone levels had a stronger effect), most evident 40 min after ingestion, and some vocal changes were sex-specific. Future studies should investigate whether the changes in vocal performance due to elevated glucocorticoids have consequences for the birds' behavior, reproductive success, and survival.


Asunto(s)
Corticosterona , Vocalización Animal , Animales , Corticosterona/sangre , Vocalización Animal/fisiología , Masculino , Femenino , Pájaros Cantores/fisiología , Pájaros Cantores/sangre , Passeriformes/fisiología , Passeriformes/sangre
17.
Commun Biol ; 7(1): 575, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750083

RESUMEN

Despite extensive research on avian vocal learning, we still lack a general understanding of how and when this ability evolved in birds. As the closest living relatives of the earliest Passeriformes, the New Zealand wrens (Acanthisitti) hold a key phylogenetic position for furthering our understanding of the evolution of vocal learning because they share a common ancestor with two vocal learners: oscines and parrots. However, the vocal learning abilities of New Zealand wrens remain unexplored. Here, we test for the presence of prerequisite behaviors for vocal learning in one of the two extant species of New Zealand wrens, the rifleman (Acanthisitta chloris). We detect the presence of unique individual vocal signatures and show how these signatures are shaped by social proximity, as demonstrated by group vocal signatures and strong acoustic similarities among distantly related individuals in close social proximity. Further, we reveal that rifleman calls share similar phenotypic variance ratios to those previously reported in the learned vocalizations of the zebra finch, Taeniopygia guttata. Together these findings provide strong evidence that riflemen vocally converge, and though the mechanism still remains to be determined, they may also suggest that this vocal convergence is the result of rudimentary vocal learning abilities.


Asunto(s)
Pájaros Cantores , Vocalización Animal , Animales , Pájaros Cantores/fisiología , Conducta Social , Nueva Zelanda , Masculino , Aprendizaje , Femenino , Evolución Biológica
18.
Virol J ; 10: 137, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23634957

RESUMEN

BACKGROUND: The low-risk human papillomavirus types 6 and 11 are responsible for approximately 90% of anogenital wart cases, with approximately 190,000 new and recurrent cases reported in the UK in 2010. The UK has recently selected the quadrivalent HPV vaccine, which conveys protection against both HPV6 and HPV 11, as part of its immunisation programme for 2012 and it is expected that this will reduce disease burden in the UK. The aims of the study were to evaluate current strategies used for the monitoring of HPV infection in genital warts and to assess the suitability of laser-capture microdissection (LCM) as a technique to improve the understanding of the natural history of HPV types associated with genital wart lesions. METHODS: DNA and RNA were extracted from whole wart, surface swabs and LCM sections from 23 patients. HPV types present were determined using the Linear Array HPV Genotyping Test (Roche), with HPV DNA viral load and mRNA expression investigated using qPCR and qRT-PCR, respectively. RESULTS: Results indicated that swabbing the surface of warts does not accurately reflect potential causative HPV types present within a wart lesion, multiple HPV types being present on the surface of the wart that are absent in the lower layers of tissue isolated by LCM. Although it was shown that HPV DNA viral load does not directly correlate with HPV mRNA load, the presence of both DNA and mRNA from a single HPV type suggested a causative role in lesion development in 8/12 (66.6%) of patients analysed, with dual infections seen in 4/12 (33.3%) cases. HPV 6 and HPV 11 were present in more than 90% of the lesions examined. CONCLUSIONS: Surface swabbing of warts does not necessarily reflect the causative HPV types. HPV type specific DNA and mRNA loads do not correlate. HPV 6 and 11 were likely to be causally involved in over 90% of the lesions. Dual infections were also found, and further studies are required to determine the biological and clinical nature of dual/multiple infections and to establish the relationship of multiple HPV types within a single lesion.


Asunto(s)
Condiloma Acuminado/virología , Papillomaviridae/clasificación , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Coinfección/virología , ADN Viral/genética , Femenino , Perfilación de la Expresión Génica , Genotipo , Humanos , Papillomaviridae/genética , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reino Unido , Carga Viral
19.
Biol Lett ; 9(6): 20130746, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24284560

RESUMEN

Overlap in the form of sexual signals such as pheromones raises the possibility of reproductive interference by invasive species on similar, yet naive native species. Here, we test the potential for reproductive interference through heterospecific mate attraction and subsequent predation of males by females of a sexually cannibalistic invasive praying mantis. Miomantis caffra is invasive in New Zealand, where it is widely considered to be displacing the only native mantis species, Orthodera novaezealandiae, and yet mechanisms behind this displacement are unknown. We demonstrate that native males are more attracted to the chemical cues of introduced females than those of conspecific females. Heterospecific pairings also resulted in a high degree of mortality for native males. This provides evidence for a mechanism behind displacement that has until now been undetected and highlights the potential for reproductive interference to greatly influence the impact of an invasive species.


Asunto(s)
Conducta Animal , Mantódeos/fisiología , Conducta Predatoria , Conducta Sexual Animal , Animales , Canibalismo , Conducta Competitiva , Femenino , Especies Introducidas , Masculino , Preferencia en el Apareamiento Animal , Nueva Zelanda , Feromonas/fisiología , Reproducción/fisiología , Especificidad de la Especie
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