Population genetics and ecological niche of invasive Aedes albopictus in Mexico.

The Asian tiger mosquito Aedes albopictus (Skuse), is one of the most invasive mosquito species worldwide. In Mexico it is now recorded in 12 states and represents a serious public health problem, given the recent introduction of Chikungunya on the southern border. The aim of this study was to analyze the population genetics of A. albopictus from all major recorded foci, and model its ecological niche. Niche similarity with that from its autochthonous distribution in Asia and other invaded countries were analyzed and its potential future expansion and potential human exposure in climate change scenarios measured. We analyzed 125 sequences of a 317 bp fragment of the cyt b gene from seven A. albopictus populations across Mexico. The samples belong to 25 haplotypes with moderate population structuring (Fst=0.081, p<0.02) and population expansion. The most prevalent haplotype, found in all principal sites, was shared with the USA, Brazil, France, Madagascar, and Reunion Island. The ecological niche model using Mexican occurrence records covers 79.7% of the country, and has an 83% overlap with the Asian niche projected to Mexico. Both Neotropical and Nearctic regions are included in the Mexican niche model. Currently in Mexico, 38.6 million inhabitants are exposed to A. albopictus, which is expected to increase to 45.6 million by 2070. Genetic evidence supports collection information that A. albopictus was introduced to Mexico principally by land from the USA and Central and South America. Prevalent haplotypes from Mexico are shared with most invasive regions across the world, just as there was high niche similarity with both natural and invaded regions. The important overlap with the Asian niche model suggests a high potential for the species to disperse to sylvatic regions in Mexico.

Familial glioblastoma.

The authors describe a family with three members affected by glioblastoma. The proband patient, a 7 year-old girl, developed a rare complication, a pulmonary metastasis. Chromosomal analysis of her peripheral blood lymphocytes showed a normal karyotype (46, XX), without structural abnormalities. Cytogenetic study of the tumor cells disclosed several abnormalities: 46, XX, 7q-/46, XX, -2, 4p-, 7p-, +15/46, XX. Some aspects about genetics of glial neoplasms are discussed.

[Perimesencephalic subarachnoid hemorrhage nonaneurysmatic: report of a case and literature review]. / Hemorragia subaracnóidea perimesencefálica não-aneurismática. Apresentação de caso e revisão de literatura.

A 42 year-old man with subarachnoid hemorrhage was admitted in our Service (Hunt & Hess grade II). CT-scan disclosed predominantly perimesencephalic subarachnoid hemorrhage. Digital subtraction angiographic study did not disclose either cerebral aneurysm or any other potential site of intracranial bleeding. The evolution was uneventful. A DSA was repeated one month later and was negative. Four months later, the patient was asymptomatic. The authors review the literature and emphasize the importance in recognizing this benign clinical form of nonaneurysmatic subarachnoid hemorrhage.