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1.
J Patient Cent Res Rev ; 11(2): 81-87, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044850

RESUMO

Purpose: The impact of central nervous system (CNS) prophylaxis in diffuse large B-cell lymphoma (DLBCL) is contentious. The CNS International Prognostic Index (IPI) calculator offers prognostic guidance in identifying those patients who may be at highest risk of disease progression or relapse to the CNS. However, it is unclear whether this tool has guided clinician decision-making in a real-world setting. Studies have suggested that CNS prophylaxis may not offer clinically significant benefit in terms of preventing CNS disease progression. Given this, we investigated the utilization of CNS prophylaxis within our own population and documentation of the CNS-IPI score. Methods: We retrospectively evaluated patients with newly diagnosed DLBCL between January 1, 2014, and December 31, 2017. Patients were assessed for receipt of CNS prophylaxis in the form of intrathecal (IT) chemotherapy and/or high-dose intravenous (IV) methotrexate. CNS-IPI scores were calculated for all patients who received CNS prophylaxis or those who experienced CNS disease. Long-term outcomes at five years from diagnosis included CNS progression/relapse and survival. Results: Of 234 patients who met criteria, 20 (8.6%) received either IV methotrexate or IT chemotherapy; most received IT methotrexate. No patients in the IT prophylaxis group developed CNS disease, while two of eight IV methotrexate patients experienced CNS disease involvement. The incidence of CNS progression was 3.7% in the no prophylaxis group and 10% in those who received prophylaxis. Conclusions: This study revealed low utilization of CNS prophylaxis and CNS-IPI documentation in a community hospital system. Given large differences between groups, claims of CNS prophylaxis efficacy are unable to be made. CNS relapse rates were consistent with existing literature and promote continued evaluation of the utility of current CNS prophylaxis approaches in DLBCL. New unambiguously effective therapeutic approaches are needed and may encourage a higher rate of standardized use.

2.
J Evol Biol ; 29(10): 1968-1976, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27306988

RESUMO

Large brains (relative to body size) might confer fitness benefits to animals. Although the putative costs of well-developed brains can constrain the majority of species to modest brain sizes, these costs are still poorly understood. Given that the neural tissue is energetically expensive and demands antioxidants, one potential cost of developing and maintaining large brains is increased oxidative stress ('oxidation exposure' hypothesis). Alternatively, because large-brained species exhibit slow-paced life histories, they are expected to invest more into self-maintenance such as an efficacious antioxidative defence machinery ('oxidation avoidance' hypothesis). We predict decreased antioxidant levels and/or increased oxidative damage in large-brained species in case of oxidation exposure, and the contrary in case of oxidation avoidance. We address these contrasting hypotheses for the first time by means of a phylogenetic comparative approach based on an unprecedented data set of four redox state markers from 85 European bird species. Large-brained birds suffered less oxidative damage to lipids (measured as malondialdehyde levels) and exhibited higher total nonenzymatic antioxidant capacity than small-brained birds, whereas uric acid and glutathione levels were independent of brain size. These results were not altered by potentially confounding variables and did not depend on how relative brain size was quantified. Our findings partially support the 'oxidation avoidance' hypothesis and provide a physiological explanation for the linkage of large brains with slow-paced life histories: reduced oxidative stress of large-brained birds can secure brain functionality and healthy life span, which are integral to their lifetime fitness and slow-paced life history.


Assuntos
Aves/fisiologia , Encéfalo/anatomia & histologia , Estresse Oxidativo , Animais , Antioxidantes , Tamanho do Órgão , Filogenia
3.
Rev Sci Instrum ; 86(3): 033507, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25832229

RESUMO

X-ray emission from a molybdenum X-pinch has been investigated as a potential probe for the high pressure states made in dynamic compression experiments. Studies were performed on a novel 300 kA, 400 ns generator which coupled the load directly to a low inductance capacitor and switch combination. The X-pinch load consisted of 4 crossed molybdenum wires of 13 µm diameter, crossed at an angle of 62°. The load height was 10 mm. An initial x-ray burst generated at the wire crossing point, radiated in the soft x-ray range (hυ < 10 keV). This was followed, 2-5 ns later, by at least one harder x-ray burst (hυ > 10 keV) whose power ranged from 1 to 7 MW. Time integrated spectral measurements showed that the harder bursts were dominated by K-alpha emission; though, a lower level, wide band continuum up to at least 30 keV was also present. Initial tests demonstrated that the source was capable of driving Laue diffraction experiments, probing uncompressed samples of LiF and aluminium.

4.
J Evol Biol ; 26(4): 878-88, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23489329

RESUMO

Natural selection is considered a major force shaping brain size evolution in vertebrates, whereas the influence of sexual selection remains controversial. On one hand, sexual selection could promote brain enlargement by enhancing cognitive skills needed to compete for mates. On the other hand, sexual selection could favour brain size reduction due to trade-offs between investing in brain tissue and in sexually selected traits. These opposed predictions are mirrored in contradictory relationships between sexual selection proxies and brain size relative to body size. Here, we report a phylogenetic comparative analysis that highlights potential flaws in interpreting relative brain size-mating system associations as effects of sexual selection on brain size in shorebirds (Charadriiformes), a taxonomic group with an outstanding diversity in breeding systems. Considering many ecological effects, relative brain size was not significantly correlated with testis size. In polyandrous species, however, relative brain sizes of males and females were smaller than in monogamous species, and females had smaller brain size than males. Although these findings are consistent with sexual selection reducing brain size, they could also be due to females deserting parental care, which is a common feature of polyandrous species. Furthermore, our analyses suggested that body size evolved faster than brain size, and thus the evolution of body size may be confounding the effect of the mating system on relative brain size. The brain size-mating system association in shorebirds is thus not only due to sexual selection on brain size but rather, to body size evolution and other multiple simultaneous effects.


Assuntos
Encéfalo/anatomia & histologia , Charadriiformes/anatomia & histologia , Seleção Genética , Animais , Evolução Biológica , Peso Corporal , Charadriiformes/classificação , Charadriiformes/genética , Feminino , Masculino , Modelos Biológicos , Tamanho do Órgão , Fenótipo , Filogenia , Fatores Sexuais , Comportamento Sexual Animal , Testículo/anatomia & histologia
5.
J Evol Biol ; 23(5): 1064-74, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20345813

RESUMO

Many mammals have brains substantially larger than expected for their body size, but the reasons for this remain ambiguous. Enlarged brains are metabolically expensive and require elongated developmental periods, and so natural selection should have favoured their evolution only if they provide counterbalancing advantages. One possible advantage is facilitating the construction of behavioural responses to unusual, novel or complex socio-ecological challenges. This buffer effect should increase survival rates and favour a longer reproductive life, thereby compensating for the costs of delayed reproduction. Here, using a global database of 493 species, we provide evidence showing that mammals with enlarged brains (relative to their body size) live longer and have a longer reproductive lifespan. Our analysis supports and extends previous findings, accounting for the possible confounding effects of other life history traits, ecological and dietary factors, and phylogenetic autocorrelation. Thus, these findings provide support for the hypothesis that mammals counterbalance the costs of affording large brains with a longer reproductive life.


Assuntos
Encéfalo/anatomia & histologia , Longevidade/fisiologia , Mamíferos/anatomia & histologia , Reprodução/fisiologia , Animais , Pesos e Medidas Corporais , Modelos Lineares , Mamíferos/fisiologia , Tamanho do Órgão/fisiologia , Filogenia , Fatores de Tempo
6.
J Am Dent Assoc ; 134(3): 331-4, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12699047

RESUMO

BACKGROUND: Human papillomaviruses, or HPV, are etiologic agents of all types of warts, including those associated with sexual transmission. Although previously rare in children, condylomata acuminata in the mouth have been reported for the past 10 to 15 years, and the possibility of sexual abuse needs to be considered. CASE DESCRIPTION: A 4-year-old boy with poor dental health presented with a wartlike mass on his upper lip, as well as two similar penile lesions. The lesions, cauliflowerlike and pedunculated in appearance, were excised, underwent biopsies and were subtyped via in situ hybridization. All of the lesions tested positive for HPV subtypes 6 and 11, which are the subtypes most often associated with anogenital warts (condylomata acuminata). Although both parents reported having genital warts, the specific mode of transmission to the child was not determined. CLINICAL IMPLICATIONS: Cases of oral condylomata acuminata in children need to be treated as possible instances of sexual abuse, and it is incumbent on the dentist to alert the appropriate community agency for follow-up.


Assuntos
Condiloma Acuminado/patologia , Doenças Labiais/patologia , Abuso Sexual na Infância , Pré-Escolar , Transmissão de Doença Infecciosa , Humanos , Masculino , Papillomaviridae/isolamento & purificação , Doenças do Pênis/patologia
7.
J Parasitol ; 87(5): 1187-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11695394

RESUMO

Feather mites (Astigmata) are distributed around the world, living on the feathers of birds, but their mechanisms for transmission among hosts are not fully understood. There is anecdotal evidence of feather mites attached to louseflies (Diptera: Hippoboscidae), suggesting that feather mites may use these flies as a mode of phoretic transmission among birds. Two bird-lousefly associations (alpine swift Apus melba-Crataerina melbae and feral pigeon Columba livia-Pseudolynchia canariensis) were inspected to test the hypothesis that feather mites use hippoboscid flies as major mode of transmission. Both bird species showed a high prevalence and abundance of feather mites and louseflies. However, no feather mites were found attached to the 405 louseflies inspected, although skin mites (Epidermoptidae and Cheyletiellidae) were found on louseflies collected from feral pigeons. This study suggests that feather mites do not use hippoboscid flies as a major mode of transmission among birds.


Assuntos
Doenças das Aves/parasitologia , Columbidae/parasitologia , Dípteros/parasitologia , Insetos Vetores/parasitologia , Ácaros/fisiologia , Animais , Doenças das Aves/transmissão , Plumas/parasitologia , Espanha
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