- Email: [email protected]
Tracking down the origins of HIV
78
News & Comment
Cannabis goes to high court The US Supreme court will consider the federal government’s arguments to ban medicinal marijuana because it compromises drug laws and has no currently accepted medical use. This development coincides with scientific efforts to more thoroughly investigate the effect of marijuana. The National Institutes of Health and institutions such as Center for Medicinal Cannabis Research at the University at San Diego are currently funding studies investigating the effect of the drug on nausea, vomiting, weight loss, muscle spasticity, and pain that is associated with peripheral neuropathy. Although the main active ingredient in marijuana, delta-9-tetrahydrocannabinol (THC), is available in pill form, it has been argued that smoked marijuana is more effective because it rapidly reaches the brain and can be easily titrated. Furthermore, others argue that the other chemicals in smoked marijuana, while making the drug ‘messy’ by traditional pharmaceutical parameters, are essential for its effects. Studies will hopefully have insights in time for the Supreme Court hearing next year. (LO)
TRENDS in Neurosciences Vol.24 No.2 February 2001
columns in cat form at a time that coincides exactly with the ‘critical period’ in the animal, in which shutting one eye disrupts the architecture of columns. By contrast, Crowley and Katz report that these columns appear in ferret before the critical period, and that removal of input from one eye has little effect in altering the anatomical appearance of columns. Additional studies are required to investigate if these columns indeed respond functionally to alternating eyes but, at the very least, scientists will be forced to rethink the idea that neural activity induces cortical organization. Crowley and Katz propose that this organization is initially caused by innate molecules that guide growing axons to their location in developing brain. Science (2000) 290, 1321–1324. (LO)
Sorting out epilepsy Presynaptic kainate receptors with distinct subunit composition could provide the key for unraveling the physiology of epilepsy. A recent study by Contractor et al. using genetargeted (mGluR5−/− and mGluR6−/−) mice to determine the receptor subunits involved in the modulation of glutamate release in the hippocampus, a brain structure that is damaged in epileptiform-type seizures. The authors concluded that receptor subunit mGluR6 is critical for mossy fiber and collateral inputs to the CA3 area, whereas a complex mix of mGluR5 and mGluR6 are required for the increase in the perforant path synaptic input onto CA3 neurons. These results further clarify the receptor compositions that underlie the activation of signaling pathways leading to synaptic hyperexcitability and neuronal cell loss. J. Neurosci. (2000) 20, 8269–8278. (SS)
Another way of looking at visual development Neuroscientists from Duke University have reported new insights on an established view of visual development. Previous studies by Nobel Laureates David Hubel and Torsten Wiesel showed that ocular dominance http://tins.trends.com
Tracking down the origins of HIV
of this study by Rampon et al. indicate that several genes are upregulated under these conditions, such as those with known functions in neuronal structure and synaptic transmission. Although structural reorganization of the brain and changes in performance in rodents against an enriched background have been reported since the 1940s, the development of new techniques for analyzing gene expression will allow novel approaches for answering the of question whether brain function is amenable to being shaped and ‘nurtured’ by environmental cues. Proc. Natl. Acad. Sci. U. S. A. (2000) 97, 12880–12884. (SS)
New Current Opinion title February sees the launch of a new review journal from the publisher of Trends in Neurosciences, Current Opinion in Pharmacology. The latest in the Current Opinion series, the new journal will follow the same formula of dedicating each bimonthly issue to one or two specific subject areas, covering developments in the past 12 months. Reviews will be commissioned by specialist Section Editors, appointed by Chief Editors Robert Ruffolo and Norman G. Bowery. The first issue will focus on Neuroscience, with Section Editors Anthony Dickenson, Jerry Gebhart and Ray Hill. The latest contents listing is available at www.current-opinion.com.
Researchers have proposed a new theory for the spread of HIV to humans based on the discovery of a 17th-century predecessor of the virus, common to humans and chimpanzees. Using genetic database analysis, the group has found that the most common form of AIDS, HIV-1 M, must have spread to humans long before the 1950s, during which the polio vaccination programs in Africa were thought to have contaminated African populations with the precursor virus found in chimps. The data suggests that transmission to man took place as a result of hunting chimpanzees for meat, and spread outwards from Africa with mass migration, decolonization and war. FASEB J. (2000) Ahead of print report. (SS)
Are you genetically fit? High-density oligonucleotide micro-array methods have been used to analyze gene expression in the brain in response to enriched environment training. The results
This months ‘In Brief’ articles were written by Sonia Sequeira ([email protected]) and Lianna Orlando ([email protected])
News & Comment
Cannabis goes to high court The US Supreme court will consider the federal government’s arguments to ban medicinal marijuana because it compromises drug laws and has no currently accepted medical use. This development coincides with scientific efforts to more thoroughly investigate the effect of marijuana. The National Institutes of Health and institutions such as Center for Medicinal Cannabis Research at the University at San Diego are currently funding studies investigating the effect of the drug on nausea, vomiting, weight loss, muscle spasticity, and pain that is associated with peripheral neuropathy. Although the main active ingredient in marijuana, delta-9-tetrahydrocannabinol (THC), is available in pill form, it has been argued that smoked marijuana is more effective because it rapidly reaches the brain and can be easily titrated. Furthermore, others argue that the other chemicals in smoked marijuana, while making the drug ‘messy’ by traditional pharmaceutical parameters, are essential for its effects. Studies will hopefully have insights in time for the Supreme Court hearing next year. (LO)
TRENDS in Neurosciences Vol.24 No.2 February 2001
columns in cat form at a time that coincides exactly with the ‘critical period’ in the animal, in which shutting one eye disrupts the architecture of columns. By contrast, Crowley and Katz report that these columns appear in ferret before the critical period, and that removal of input from one eye has little effect in altering the anatomical appearance of columns. Additional studies are required to investigate if these columns indeed respond functionally to alternating eyes but, at the very least, scientists will be forced to rethink the idea that neural activity induces cortical organization. Crowley and Katz propose that this organization is initially caused by innate molecules that guide growing axons to their location in developing brain. Science (2000) 290, 1321–1324. (LO)
Sorting out epilepsy Presynaptic kainate receptors with distinct subunit composition could provide the key for unraveling the physiology of epilepsy. A recent study by Contractor et al. using genetargeted (mGluR5−/− and mGluR6−/−) mice to determine the receptor subunits involved in the modulation of glutamate release in the hippocampus, a brain structure that is damaged in epileptiform-type seizures. The authors concluded that receptor subunit mGluR6 is critical for mossy fiber and collateral inputs to the CA3 area, whereas a complex mix of mGluR5 and mGluR6 are required for the increase in the perforant path synaptic input onto CA3 neurons. These results further clarify the receptor compositions that underlie the activation of signaling pathways leading to synaptic hyperexcitability and neuronal cell loss. J. Neurosci. (2000) 20, 8269–8278. (SS)
Another way of looking at visual development Neuroscientists from Duke University have reported new insights on an established view of visual development. Previous studies by Nobel Laureates David Hubel and Torsten Wiesel showed that ocular dominance http://tins.trends.com
Tracking down the origins of HIV
of this study by Rampon et al. indicate that several genes are upregulated under these conditions, such as those with known functions in neuronal structure and synaptic transmission. Although structural reorganization of the brain and changes in performance in rodents against an enriched background have been reported since the 1940s, the development of new techniques for analyzing gene expression will allow novel approaches for answering the of question whether brain function is amenable to being shaped and ‘nurtured’ by environmental cues. Proc. Natl. Acad. Sci. U. S. A. (2000) 97, 12880–12884. (SS)
New Current Opinion title February sees the launch of a new review journal from the publisher of Trends in Neurosciences, Current Opinion in Pharmacology. The latest in the Current Opinion series, the new journal will follow the same formula of dedicating each bimonthly issue to one or two specific subject areas, covering developments in the past 12 months. Reviews will be commissioned by specialist Section Editors, appointed by Chief Editors Robert Ruffolo and Norman G. Bowery. The first issue will focus on Neuroscience, with Section Editors Anthony Dickenson, Jerry Gebhart and Ray Hill. The latest contents listing is available at www.current-opinion.com.
Researchers have proposed a new theory for the spread of HIV to humans based on the discovery of a 17th-century predecessor of the virus, common to humans and chimpanzees. Using genetic database analysis, the group has found that the most common form of AIDS, HIV-1 M, must have spread to humans long before the 1950s, during which the polio vaccination programs in Africa were thought to have contaminated African populations with the precursor virus found in chimps. The data suggests that transmission to man took place as a result of hunting chimpanzees for meat, and spread outwards from Africa with mass migration, decolonization and war. FASEB J. (2000) Ahead of print report. (SS)
Are you genetically fit? High-density oligonucleotide micro-array methods have been used to analyze gene expression in the brain in response to enriched environment training. The results
This months ‘In Brief’ articles were written by Sonia Sequeira ([email protected]) and Lianna Orlando ([email protected])