Description of the immatures of the ant, Myrmelachista catharinae

The Neotropical ant genus Myrmelachista Roger comprises 69 described species and subspecies, and still is a poorly studied group. Larvae play a paramount role in colony nutrition in social hymenopterans and bear considerable value in the reconstruction of group phylogenies, however, they are generally neglected. Larvae of different instars of Myrmelachista catharinae Mayr (Hymenoptera: Formicidae) are herein described in detail by light and scanning electron microscopy. The number of larval instars was estimated as three based on the frequency distribution of maximum head capsule widths. The described larvae confirmed some traits typical of the genus: general shape of body and mandibles, general aspect and distribution of body hairs, and the number of sensilla on the palps and galea. Differently from other Myrmelachista larvae previously described, M. catharinae presented two distinct kinds of second instars, some additional types of body hairs, different number of antennal sensilla, and a distinct labrum shape. M. catharinae presented ten pairs of spiracles, which is the first record for this genus.

The Effect of Spatial Scale on Predicting Time Series: A Study on Epidemiological System Identification

A susceptible-infective-recovered (SIR) epidemiological model based on probabilistic cellular automaton (PCA) is employed for simulating the temporal evolution of the registered cases of chickenpox in Arizona, USA, between 1994 and 2004. At each time step, every individual is in one of the states S, I, or R. The parameters of this model are the probabilities of each individual (each cell forming the PCA lattice ) passing from a state to another state. Here, the values of these probabilities are identified by using a genetic algorithm. If nonrealistic values are allowed to the parameters, the predictions present better agreement with the historical series than if they are forced to present realistic values. A discussion about how the size of the PCA lattice affects the quality of the model predictions is presented. Copyright (C) 2009 L. H. A. Monteiro et al.

Detection of the bacterium, Xylella fastidiosa, in saliva of glassy-winged sharpshooter, Homalodisca vitripennis

Homalodisca vitripennis ( Germar) ( Hemiptera: Cicadellidae), the glassy- winged sharpshooter, is one of the most important vectors of the bacterium, Xylella fastidiosa subsp. piercei ( Xanthomonadales: Xanthomonadaceae) that causes Pierce's Disease in grapevines in California. In the present study we report a new method for studying pathogen transmission or probing behavior of H. vitripennis. When confined, H. vitripennis attempt to probe the surface of sterile containers 48 hours post- acquisition of X. f. piercei. The saliva deposited during attempted feeding probes was found to contain X. f. piercei. We observed no correlation between X. f. piercei titers in the foregut of H. vitripennis that fed on Xylella- infected grapevines and the presence of this bacterium in the deposited saliva. The infection rate after a 48 h post- acquisition feeding on healthy citrus and grapevines was observed to be 77% for H. vitripennis that fed on grapevines and 81% for H. vitripennis that fed on citrus, with no difference in the number of positive probing sites from H. vitripennis that fed on either grapevine or citrus. This method is amenable for individual assessment of X. f. piercei- infectivity, with samples less likely to be affected by tissue contamination that is usually present in whole body extracts.

South American spider mites: New hosts and localities

In order to contribute to taxonomic information on Tetranychid mites (Acari: Tetranychidae) in South America, surveys were conducted in Brazil (15 States and the Federal District) and Uruguay (one Department); 550 samples of 120 plant species were collected. Tetranychid mite infestations were confirmed in 204 samples, and 22 species belonging to seven genera of the Bryobiinae and Tetranychinae subfamilies were identified on 58 different host plants. Thirty-six new plant hosts were found in Brazil, South America, and worldwide for the following species: Eutetranychus banksi (McGregor); Mononychellus tanajoa (Bondar); Oligonychus anonae Paschoal; O. mangiferus (Rahman and Sapra); Tetranychus bastosi Tuttle, Baker and Sales; T. desertorum Banks, 1900, T. evansi Baker and Pritchard; T. ludeni Zacher; T. mexicanus (McGregor); T. neocaledonicus Andre; and T. urticae Koch. Four new localities in Brazil were reported for Eotetranychus tremae De Leon; O. anonae; Panonychus ulmi (Koch); and T. gloveri Baker and Pritchard.

Comparison of language impairment in late-onset depression and Alzheimer`s disease

Objectives: Depression and dementia are highly prevalent in the elderly. Language impairment is an inherent component of Alzheimer`s disease (AD), which can also be encountered in depressed patients. The aim of this study wasto compare the profiles of language abilities in late-onset depression and mild AD groups. Methods: We studied 25 patients with late-onset depression (mean age 73.6 +/- 6.6 years; schooling 9.1 +/- 5.7 years) and 30 patients with mild AD (77.6 +/- 5.4 years; 7.5 +/- 7.1 years) using the Arizona Battery for Communication Disorders of Dementia (ABCD), compared to a group of 30 controls (73.8 +/- 5.8 years; 9.1 +/- 5.4 years). Cut-off scores to discriminate between Controls x Depression and Depression x AD were determined. Results: Depressed patients` scores were similar to AD in confrontation naming, concept definition, following commands, repetition and reading comprehension (sentence). Episodic memory and mental status subtests were useful in differentiating depressed patients from AD, a result that was reproduced when using analysis of covariance to control for the effect of age in the same subtests (p = 0.01 and 0.04, respectively). Conclusion: Language impairment resembling AD was found in the aforementioned language subtests of the ABCD in elderly depressed patients; the mental status and episodic memory subtests were useful to discriminate between AD and depression. The ABCD has proven to be a suitable tool for language evaluation in this population and should aid in the differentiation of AD and pseudodementia (as that of depression).

Insulin-like peptide genes in honey bee fat body respond differently to manipulation of social behavioral physiology

Nutrient sensitive insulin-like peptides (ILPs) have profound effects on invertebrate metabolism, nutrient storage, fertility and aging. Many insects transcribe ILPs in specialized neurosecretory cells at changing levels correlated with life history. However, the major site of insect metabolism and nutrient storage is not the brain, but rather the fat body, where functions of ILP expression are rarely studied and poorly understood. Fat body is analogous to mammalian liver and adipose tissue, with nutrient stores that often correlate with behavior. We used the honey bee (Apis mellifera), an insect with complex behavior, to test whether ILP genes in fat body respond to experimentally induced changes of behavioral physiology. Honey bee fat body influences endocrine state and behavior by secreting the yolk protein precursor vitellogenin (Vg), which suppresses lipophilic juvenile hormone and social foraging behavior. In a two-factorial experiment, we used RNA interference (RNAi)-mediated vg gene knockdown and amino acid nutrient enrichment of hemolymph (blood) to perturb this regulatory module. We document factor-specific changes in fat body ilp1 and ilp2 mRNA, the bee`s ILP-encoding genes, and confirm that our protocol affects social behavior. We show that ilp1 and ilp2 are regulated independently and differently and diverge in their specific expression-localization between fat body oenocyte and trophocyte cells. Insect ilp functions may be better understood by broadening research to account for expression in fat body and not only brain.

Constitutional Telomerase Mutations Are Genetic Risk Factors for Cirrhosis

Some patients with liver disease progress to cirrhosis, but the risk factors for cirrhosis development are unknown. Dyskeratosis congenita, an inherited bone marrow failure syndrome associated with mucocutaneous anomalies, pulmonary fibrosis, and cirrhosis, is caused by germline mutations of genes in the telomerase complex. We examined whether telomerase mutations also occurred in sporadic cirrhosis. In all, 134 patients with cirrhosis of common etiologies treated at the Liver Research Institute, University of Arizona, between May 2008 and July 2009, and 528 healthy subjects were screened for variation in the TERT and TERC genes by direct sequencing; an additional 1,472 controls were examined for the most common genetic variation observed in patients. Telomere length of leukocytes was measured by quantitative polymerase chain reaction. Functional effects of genetic changes were assessed by transfection of mutation-containing vectors into telomerase-deficient cell lines, and telomerase activity was measured in cell lysates. Nine of the 134 patients with cirrhosis (7%) carried a missense variant in TERT, resulting in a cumulative carrier frequency significantly higher than in controls (P = 0.0009). One patient was homozygous and eight were heterozygous. The allele frequency for the most common missense TERT variant was significantly higher in patients with cirrhosis (2.6%) than in 2,000 controls (0.7%; P = 0.0011). One additional patient carried a TERC mutation. The mean telomere length of leukocytes in patients with cirrhosis, including six mutant cases, was shorter than in age-matched controls (P = 0.0004). Conclusion: Most TERT gene variants reduced telomerase enzymatic activity in vitro. Loss-of-function telomerase gene variants associated with short telomeres are risk factors for sporadic cirrhosis. (HEPATOLOGY 2011;53:1600-1607)

CHRONOLOGICAL DISTRIBUTION OF BRAZILIAN GLYPTODON SP REMAINS: A DIRECT (14)C DATE FOR A SPECIMEN FROM IPORANGA, SAO PAULO, BRAZIL

Glyptodon sp. fossil remains can be found throughout Brazil. However, little information is available about their chronological distribution. With the intention to contribute to this issue, we present, as far as we know, the first direct radiocarbon date for 1 specimen of this genus found in Brazil. The osteoderm MZSP-PV660 found in Abismo do Fossil Cave (SP-145), Iporanga, Sao Paulo, Brazil, was dated by accelerator mass spectrometry at the Beta Analytic Radiocarbon Dating Laboratory. The (14)C date obtained was between 20,680 and 21,370 calibrated years before the present. Unfortunately, the scant (and often imprecise or unreliable) chronological data regarding this species and genus in Brazil and elsewhere in South America precludes a robust comparison among the dates available and the one presented here. Nevertheless, our finding supports the existence of this genus in South America at least until the Last Glacial Maximum.