28 research outputs found
Sample collection from asteroid (162173) Ryugu by Hayabusa2: Implications for surface evolution
International audienc
Molecular Mechanisms Associated with Nicotine Pharmacology and Dependence.
Tobacco dependence is a leading cause of preventable disease and death worldwide. Nicotine, the main psychoactive component in tobacco cigarettes, has also been garnering increased popularity in its vaporized form, as derived from e-cigarette devices. Thus, an understanding of the molecular mechanisms underlying nicotine pharmacology and dependence is required to ascertain novel approaches to treat drug dependence. In this chapter, we review the field's current understanding of nicotine's actions in the brain, the neurocircuitry underlying drug dependence, factors that modulate the function of nicotinic acetylcholine receptors, and the role of specific genes in mitigating the vulnerability to develop nicotine dependence. In addition to nicotine's direct actions in the brain, other constituents in nicotine and tobacco products have also been found to alter drug use, and thus, evidence is provided to highlight this issue. Finally, currently available pharmacotherapeutic strategies are discussed, along with an outlook for future therapeutic directions to achieve to the goal of long-term nicotine cessation
ORIGIN AND PREVALENCE OF HUMAN T-LYMPHOTROPIC VIRUS TYPE 1 (HTLV-1) AND TYPE 2 (HTLV-2) AMONG INDIGENOUS POPULATIONS IN THE AMERICAS
Human T-lymphotropic virus type 1 (HTLV-1) is found in indigenous peoples of the Pacific Islands and the Americas, whereas type 2 (HTLV-2) is widely distributed among the indigenous peoples of the Americas, where it appears to be more prevalent than HTLV-1, and in some tribes of Central Africa. HTLV-2 is considered ancestral in the Americas and is transmitted to the general population and injection drug users from the indigenous population. In the Americas, HTLV-1 has more than one origin, being brought by immigrants in the Paleolithic period through the Bering Strait, through slave trade during the colonial period, and through Japanese immigration from the early 20th century, whereas HTLV-2 was only brought by immigrants through the Bering Strait. The endemicity of HTLV-2 among the indigenous people of Brazil makes the Brazilian Amazon the largest endemic area in the world for its occurrence. A review of HTLV-1 in all Brazilian tribes supports the African origin of HTLV-1 in Brazil. The risk of hyperendemicity in these epidemiologically closed populations and transmission to other populations reinforces the importance of public health interventions for HTLV control, including the recognition of the infection among reportable diseases and events
HTLV-1 antibodies in serum and cerebrospinal fluid in tropical spastic paraparesis in Brazil
HTLV-l antibodies were investigated in serum and in CSF of 150 patients with neurologic disorders mainly myelopathies. The patients were considered into three groups according to the possible relationship of their disease to the presence of HTLV-l antibodies: no relationship risk (control group), occasional risk group, and possible risk group. In this latter are 56 patients with crural spastic paraparesis or paraplegia of unknown etiology (SP). HTLV-l antibodies were tested by the passive particle-agglutination method for anti-ATLA antibody detection. The search was negative in all patients of the control group, and positive (serum and/or CSF) in 16.5% of the patients from the second group and in 55.4% of the SP patients group. Clinical patterns in SP cases with HTLV-l antibodies were those of tropical spastic paraparesis (TSP). CSF patterns considered (cytology, protein content and gamma-globulins rate) were different between TSP group with HTLV-l antibodies in CSF and SP group with no HTLV-l antibodies detection either in serum or in CSF. The difference was significant. Results of this investigation confirm the high incidence of TSP in Brazil, and bring additional indication for searching HTLV-l antibodies in the CSF