469 resultados para Tribe Paini
Resumo:
Diaugia angusta Perty, 1833 is a Neotropical species of Tachinidae (Diptera) reported here as a parasitoid of Metamasius ensirostris (Germar, 1824) and M hemipterus (Linnaeus, 1758) (Coleoptera: Dryophthoridae) in Brazil. Several species of Dryophthoridae and Curculionidae cause damage to bromeliad and palm species, and most are regarded as pests. In the present study, the male and female of D. angusta are morphologically characterized and illustrated to provide a means for the identification of this parasitoid. Data obtained from preliminary field research show that natural parasitism of Metamasius pupae by D. angusta varies by year but can reach nearly 30%. A network of parasitoid-host interactions among tachinid parasitoids and coleopteran hosts reported as bromeliad and palm pests (Dryophthoridae and Curculionidae) in the Americas indicates that the species of the tribe Dexiini sensu lam (including D. angusta) might be promising as biological control agents of these pests.
Resumo:
Fungus-growing ants of the genus Mycetarotes are among the least studied in the tribe Attini. This report documents nest architecture and worker population numbers for 19 nests of M. parallelus and 5 nests of M. acutus, including the first such report for M. acutus. This new information is integrated with the scant biological information reported on Mycetarotes to date. The resulting picture of Mycetarotes life history, as well as the relative ease with which large numbers of nests can be collected and observed in the field, suggest that Mycetarotes (particularly M. parallelus) is an ideal model system for the study of coevolution of lower-attine ants and their cultivated fungi.
Resumo:
Studies indicate that overweight and obesity protect against HIV-disease progression in antiretroviral therapy (ART)-naïve patients. We examined retrospectively the relationship of overweight/obesity with HIV-disease progression in ART-naïve HIV+ adults in Botswana in a case-control study with 18-month follow-up, which included 217 participants, 139 with BMI 18.0-24.9 kg/m 2 and 78 with BMI ≥25 kg/m2. Archived plasma samples were used to determine inflammatory markers: leptin and bacterial endotoxin lipopolysaccharide (LPS), and genotype single nucleotide polymorphisms (SNPs) of the Fat Mass and Obesity Associated Gene (FTO). ^ At baseline, BMI was inversely associated with risk for AIDS-defining conditions (HR=0.218; 95%CI=0.068, 0.701, P=0.011), and higher fat mass was associated with reduced risk of the combined outcome of CD4+cell count ≤250/µL and AIDS-defining conditions, whichever occurred earlier (HR=0.918; 95%CI=0.847, 0.994, P=0.036) over 18 months, adjusting for age, gender, marriage, children, and baseline CD4+cell count and HIV-viral load. ^ FTO-SNP rs17817449 was associated with BMI (OR=1.082; 95%CI=1.001, 1.169; P=0.047). Fat mass was associated with the risk alleles of rs1121980 (OR=1.065; 95%CI=1.009, 1.125, P=0.021), rs8050136 (OR=1.078; 95%CI=1.021, 1.140; P=0.007), and rs17817449 (OR=1.086; 95%CI=1.031, 1.145; P=0.002), controlling for age, gender, tribe, total energy intake, and activity. There were no associations of SNPs with markers of disease progression. ^ Leptin levels were positively associated with BMI (β=1.764; 95%CI=0.788, 2.739; P=0.022) and fat mass (β=0.112; 95%CI=0.090, 0.135; P<0.001), but inversely with viral load (β=-0.305; 95%CI=-0.579, -.031; P=0.030). LPS levels were inversely associated with BMI (OR=0.790, 95%CI=0.630, 0.990; P=0.041), and fat mass (OR=0.852, 95%CI=0.757, 0.958; P=0.007) and directly with viral load (OR=2.608, 95%CI=1.111, 6.124; P=0.028), adjusting for age, gender, smoking and %fat mass. ^ In this cohort, overweight/obesity predicted slower HIV-disease progression. Obesity may confer an advantage in maintaining fat stores to support the overactive immune system. FTO-SNPs may contribute to the variation in fat mass; however, they were not associated with HIV-disease progression. Our findings suggest that the obesity paradox may be explained by the association of increased LPS with lower BMI and higher viral load; while viral load decreased with increasing leptin levels. Studies in African populations are needed to clarify whether genetic variation and inflammation mediate the obesity paradox in HIV-disease progression.^
Resumo:
The tribe Longidorini within the subfamily Longidorinae (Longidorus spp. and Paralongidorus spp.) and the subfamily Xiphineminae (Xiphinema spp.) are two large nematode groups with about 260 and 230 known species, respectively. They are globally two important groups of ectoparasitic nematodes considered to be major pests because of their activity as vectors of important plant nepovirus, with some species included in the list of quarantine pathogenic organisms in many European countries. Knowledge of the biodiversity and occurrence of this nematode group is a prerequisite for the establishment of sound management strategies and control measures. According to data collected from the databases (such as EPPO, FSTA, and Web of Science) and published in specialised literature, a total of 15 Longidorus, 1 Paralongidorus and 40 Xiphinema species have been recorded as present in Portugal. However, the taxonomic status of some species is controversial, and thus needs to be clarified. A comprehensive review for unravelling the biodiversity and occurrence of nematode species of the genus Longidorus, Paralongidorus and Xiphinema in Portugal is herein provided. This review includes an updated checklist of species with information on the localities, host plants and geographical distribution. Additionally, maps on the species distributions of Longidorinae and Xiphineminae nematodes present in Continental Portugal and the Portuguese Macaronesian islands are provided, as well as unpublished data on authors and comments on the current taxonomic status. Finally, new insights and directions for future research on Longidoridae in Portugal are presented.