The use of zootherapeutics in folk veterinary medicine in the district of Cubati, Paraíba State, Brazil

Background

Viewed through the micro focus of an interpretive lens, medical anthropology remains mystified because interpretivist explanations seriously downplay the given context in which individual health seeking-behaviours occur. This paper draws upon both the interpretivist and political economy perspectives to reflect on the ethno medical practices within the Korean-Australian community in Sydney.

Methods

We draw on research data collected between 1995 and 1997 for an earlier study of the use of biomedical and traditional medicine by Korean-Australians in Sydney. A total of 120 interviews were conducted with a range of participants, including biomedical doctors, traditional health professionals, Korean community leaders and Korean migrants representing a range of socio-economic backgrounds and migration patterns.

Results and Discussion

First, the paper highlights the extent to which the social location of migrants in a host society alters or restructures their initial cultural practices they bring with them. Second, taking hanbang medicine in the Korean-Australian community as an illustrative case, the paper explores the transformation of the dominant biomedicine in Australia as a result of the influx of ethnomedicine in the era of global capitalism and global movement.

Conclusion

In seeking to explain the popularity and supply of alternative health care, it is important to go beyond the culture of each kind of health care itself and to take into consideration the changes occurring at societal, national and global levels as well as consequential individual response to the changes. New social conditions influence the choice of health care methods, including herbal/alternative medicine, health foods and what are often called New Age therapies.     

Evaluation of the prevalence and economic burden of adverse drug reactions presenting to the medical emergency department of a tertiary referral centre: a prospective study

Background  

Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India     

Changes in Brazilian Drosophilidae (Diptera) assemblages across an urbanisation gradient

The present study aims to characterise the assemblages of Drosophilidae sampled from four sites subject to different levels of urbanisation, in the city of Florianópolis, South Brazil. Five samples were collected between August 2000 and August 2001 and five between August 2002 and August 2003 in each site. A gradual change in the dominant species was observed in the urbanisation gradient, with an increase in relative abundance of exotic species in urban areas. Among the native species, the relative abundance of Drosophila capricorni Dobzhansky & Pavan had an expressive decrease. In the other hand the richness in the low urbanisation site increased, probably due to the presence of urban gardens. The diversity index did not vary significantly among sites, but its correlation with evenness and richness changed.     

Study of the Drosophilidae (Diptera) communities on Atlantic Forest islands of Santa Catarina State, Brazil

A study of the community dynamics of Drosophilidae was carried out in six insular communities and two others on the mainland. Seasonal collections were carried out throughout two years in Santa Catarina State, southern of Brazil. The diversity index calculations show high values when compared with temperate climate communities. The sites on the mainland (Serra do Tabuleiro) presented the highest diversity, which was measured by the Diversity Index (H'). These sites are covered by primary Atlantic Forest and theoretically should have a higher variation of ecological niches. A dendogram showing the similarity between the communities, calculated by Morisita Index, points to a level of similarity equal to 60% for all communities. In this diagram, we can see two clades: one on the mainland and the other on the islands. The six island sites are grouped into one clade and separated into two subclades, one including the sites on Santa Catarina Island and the other consisting of the islands adjacent to this last and very much larger one. These groupings show the very important role of the spatial component on the prediction of the structure of the communities. This fact raises the discussion about the high complexity of the Atlantic Forest ecosystem and consequently the unpredictability of its fauna, highlighting the need of its conservation.     

Detecting Protein–Protein Interactions in Living Cells: Development of a Bioluminescence Resonance Energy Transfer Assay to Evaluate the PSD-95/NMDA Receptor Interaction

The PDZ domain mediated interaction between the NMDA receptor and its intracellular scaffolding protein, PSD-95, is a potential target for treatment of ischemic brain diseases. We have recently developed a number of peptide analogues with improved affinity for the PDZ domains of PSD-95 compared to the endogenous C-terminal peptide of the NMDA receptor, as evaluated by a cell-free protein–protein interaction assay. However, it is important to address both membrane permeability and effect in living cells. Therefore a bioluminescence resonance energy transfer (BRET) assay was established, where the C-terminal of the NMDA receptor and PDZ2 of PSD-95 were fused to green fluorescent protein (GFP) and Renilla luciferase (Rluc) and expressed in COS7 cells. A robust and specific BRET signal was obtained by expression of the appropriate partner proteins and subsequently, the assay was used to evaluate a Tat-conjugated peptide for its ability to disrupt the PSD-95/NMDA receptor interaction in living cells.     

RamA, a Protein Required for Reductive Activation of Corrinoid-dependent Methylamine Methyltransferase Reactions in Methanogenic Archaea

Archaeal methane formation from methylamines is initiated by distinct methyltransferases with specificity for monomethylamine, dimethylamine, or trimethylamine. Each methylamine methyltransferase methylates a cognate corrinoid protein, which is subsequently demethylated by a second methyltransferase to form methyl-coenzyme M, the direct methane precursor. Methylation of the corrinoid protein requires reduction of the central cobalt to the highly reducing and nucleophilic Co(I) state. RamA, a 60-kDa monomeric iron-sulfur protein, was isolated from Methanosarcina barkeri and is required for in vitro ATP-dependent reductive activation of methylamine:CoM methyl transfer from all three methylamines. In the absence of the methyltransferases, highly purified RamA was shown to mediate the ATP-dependent reductive activation of Co(II) corrinoid to the Co(I) state for the monomethylamine corrinoid protein, MtmC. The ramA gene is located near a cluster of genes required for monomethylamine methyltransferase activity, including MtbA, the methylamine-specific CoM methylase and the pyl operon required for co-translational insertion of pyrrolysine into the active site of methylamine methyltransferases. RamA possesses a C-terminal ferredoxin-like domain capable of binding two tetranuclear iron-sulfur proteins. Mutliple ramA homologs were identified in genomes of methanogenic Archaea, often encoded near methyltrophic methyltransferase genes. RamA homologs are also encoded in a diverse selection of bacterial genomes, often located near genes for corrinoid-dependent methyltransferases. These results suggest that RamA mediates reductive activation of corrinoid proteins and that it is the first functional archetype of COG3894, a family of redox proteins of unknown function.Most methanogenic Archaea are capable of producing methane only from carbon dioxide. The Methanosarcinaceae are a notable exception as representatives are capable of methylotrophic methanogenesis from methylated amines, methylated thiols, or methanol. Methanogenesis from these substrates requires methylation of 2-mercaptoethanesulfonic acid (coenzyme M or CoM) that is subsequently used by methylreductase to generate methane and a mixed disulfide whose reduction leads to energy conservation (1–4).Methylation of CoM with trimethylamine (TMA),⁴ dimethylamine (DMA), or monomethylamine (MMA) is initiated by three distinct methyltransferases that methylate cognate corrinoid-binding proteins (3). MtmB, the MMA methyltransferase, specifically methylates cognate corrinoid protein, MtmC, with MMA (see Fig. 1) (5, 6). The DMA methyltransferase, MtbB, and its cognate corrinoid protein, MtbC, interact specifically to demethylate DMA (7, 8). TMA is demethylated by the TMA methyltransferase (MttB) in conjunction with the TMA corrinoid protein (MttC) (8, 9). Each of the methylated corrinoid proteins is a substrate for a methylcobamide:CoM methyltransferase, MtbA, which produces methyl-CoM (10–12).Open in a separate windowFIGURE 1.MMA:CoM methyl transfer. A schematic of the reactions catalyzed by MtmB, MtmC, and MtbA is shown that emphasizes the key role of MtmC in the catalytic cycle of both methyltransferases. Oxidation to Co(II)-MtmC of the supernucleophilic Co(I)-MtmC catalytic intermediate inactivates methyl transfer from MMA to the thiolate of coenzyme M (HSCoM). In vitro reduction of the Co(II)-MtmC with either methyl viologen reduced to the neutral species or with RamA in an ATP-dependent reaction can regenerate the Co(I) species. In either case in vitro Ti(III)-citrate is the ultimate source of reducing power.CoM methylation with methanol requires the methyltransferase MtaB and the corrinoid protein MtaC, which is then demethylated by another methylcobamide:CoM methyltransferase, MtaA (13–15). The methylation of CoM with methylated thiols such as dimethyl sulfide in Methanosarcina barkeri is catalyzed by a corrinoid protein that is methylated by dimethyl sulfide and demethylated by CoM, but in this case an associated CoM methylase carries out both methylation reactions (16).In bacteria, analogous methyltransferase systems relying on small corrinoid proteins are used to achieve methylation of tetrahydrofolate. In Methylobacterium spp., CmuA, a single methyltransferase with a corrinoid binding domain, along with a separate pterin methylase, effect the methylation of tetrahydrofolate with chloromethane (17, 18). In Acetobacterium dehalogenans and Moorella thermoacetica various three-component systems exist for specific demethylation of different phenylmethyl ethers, such as vanillate (19) and veratrol (20), again for the methylation of tetrahydrofolate. Sequencing of the genes encoding the corrinoid proteins central to the archaeal and bacterial methylotrophic pathways revealed they are close homologs. Furthermore, genes predicted to encode such corrinoid proteins and pterin methyltransferases are widespread in bacterial genomes, often without demonstrated metabolic function. All of these corrinoid proteins are similar to the well characterized cobalamin binding domain of methionine synthase (21, 22).In contrast, the TMA, DMA, MMA, and methanol methyltransferases are not homologous proteins. The methylamine methyltransferases do share the common distinction of having in-frame amber codons (6, 8) within their encoding genes that corresponds to the genetically encoded amino acid pyrrolysine (23–25). Pyrrolysine has been proposed to act in presenting a methylammonium adduct to the central cobalt ion of the corrinoid protein for methyl transfer (3, 23, 26). However, nucleophilic attack on a methyl donor requires the central cobalt ion of a corrinoid cofactor is in the nucleophilic Co(I) state rather than the inactive Co(II) state (27). Subsequent demethylation of the methyl-Co(III) corrinoid cofactor regenerates the nucleophilic Co(I) cofactor. The Co(I)/Co(II) in the cobalamin binding domain of methionine synthase has an E_m value of -525 mV at pH 7.5 (28). It is likely to be similarly low in the homologous methyltrophic corrinoid proteins. These low redox potentials make the corrinoid cofactor subject to adventitious oxidation to the inactive Co(II) state (Fig. 1).During isolation, these corrinoid proteins are usually recovered in a mixture of Co(II) or hydroxy-Co(III) states. For in vitro studies, chemical reduction can maintain the corrinoid protein in the active Co(I) form. The methanol:CoM or the phenylmethyl ether:tetrahydrofolate methyltransferase systems can be activated in vitro by the addition of Ti(III) alone as an artificial reductant (14, 19). In contrast, activation of the methylamine corrinoid proteins further requires the addition of methyl viologen as a redox mediator. Ti(III) reduces methyl viologen to the extremely low potential neutral species. In vitro activation with these agents does not require ATP (5, 7, 9).Cellular mechanisms also exist to achieve the reductive activation of corrinoid cofactors in methyltransferase systems. Activation of human methionine synthase involves reduction of the co(II)balamin by methionine synthase reductase (29), whereas the Escherichia coli enzyme requires flavodoxin (30). The endergonic reduction is coupled with the exergonic methylation of the corrinoid with S-adenosylmethionine (27). An activation system exists in cellular extracts of A. dehalogenans that can activate the veratrol:tetrahydrofolate three-component system and catalyze the direct reduction of the veratrol-specific corrinoid protein to the Co(I) state; however, the activating protein has not been purified (31).For the methanogen methylamine and methanol methyltransferase systems, an activation process is readily detectable in cell extracts that is ATP- and hydrogen-dependent (32, 33). Daas et al. (34, 35) examined the activation of the methanol methyltransferase system in M. barkeri and purified in low yield a methyltransferase activation protein (MAP) which in the presence of a preparation of hydrogenase and uncharacterized proteins was required for ATP-dependent reductive activation of methanol:CoM methyl transfer. MAP was found to be a heterodimeric protein without a UV-visible detectable prosthetic group. Unfortunately, no protein sequence has been reported for MAP, leaving the identity of the gene in question. The same MAP protein was also suggested to activate methylamine:CoM methyl transfer, but this suggestion was based on results with crude protein fractions containing many cellular proteins other than MAP (36).Here we report of the identification and purification to near-homogeneity of RamA (reductive activation of methyltransfer, amines), a protein mediating activation of methylamine:CoM methyl transfer in a highly purified system (Fig. 1). Quite unlike MAP, which was reported to lack prosthetic groups, RamA is an iron-sulfur protein that can catalyze reduction of a corrinoid protein such as MtmC to the Co(I) state in an ATP-dependent reaction (Fig. 1). Peptide mapping of RamA allowed identification of the gene encoding RamA and its homologs in the genomes of Methanosarcina spp. RamA belongs to COG3894, a group of uncharacterized metal-binding proteins found in a number of genomes. RamA, thus, provides a functional example for a family of proteins widespread among bacteria and Archaea whose physiological role had been largely unknown.     

An ER‐resident membrane protein complex regulates nicotinic acetylcholine receptor subunit composition at the synapse

Nicotinic acetylcholine receptors (nAChRs) are homo‐ or heteropentameric ligand‐gated ion channels mediating excitatory neurotransmission and muscle activation. Regulation of nAChR subunit assembly and transfer of correctly assembled pentamers to the cell surface is only partially understood. Here, we characterize an ER transmembrane (TM) protein complex that influences nAChR cell‐surface expression and functional properties in Caenorhabditis elegans muscle. Loss of either type I TM protein, NRA‐2 or NRA‐4 (n icotinic r eceptor a ssociated), affects two different types of muscle nAChRs and causes in vivo resistance to cholinergic agonists. Sensitivity to subtype‐specific agonists of these nAChRs is altered differently, as demonstrated by whole‐cell voltage‐clamp of dissected adult muscle, when applying exogenous agonists or after photo‐evoked, channelrhodopsin‐2 (ChR2) mediated acetylcholine (ACh) release, as well as in single‐channel recordings in cultured embryonic muscle. These data suggest that nAChRs desensitize faster in nra‐2 mutants. Cell‐surface expression of different subunits of the ‘levamisole‐sensitive’ nAChR (L‐AChR) is differentially affected in the absence of NRA‐2 or NRA‐4, suggesting that they control nAChR subunit composition or allow only certain receptor assemblies to leave the ER.