Herbal medicine use in the districts of Nakapiripirit, Pallisa, Kanungu, and Mukono in Uganda

ABSTRACT: BACKGROUND: Traditional medicine (TM) occupies a special place in the management of diseases in Uganda. Not with standing the many people relying on TM, indigenous knowledge (IK) related to TM is getting steadily eroded. To slow down this loss it is necessary to document and conserve as much of the knowledge as possible. This study was conducted to document the IK relevant to traditional medicine in the districts of Mukono, Nakapiripirit, Kanungu and Pallisa, in Uganda. METHODS: An ethnobotanical survey was conducted between October 2008 and February 2009 using techniques of key informant interviews and household interviews. RESULTS: The common diseases and conditions in the four districts include malaria, cough, headache, diarrhea, abdominal pain, flu, backache and eye diseases. Respondents stated that when they fall sick they self medicate using plant medicines or consult western-trained medicine practitioners. Self medication using herbal medicines was reported mostly by respondents of Nakapiripirit and Mukono. Respondents have knowledge to treat 78 ailments using herbal medicines. 44 species, mentioned by three or more respondents have been prioritized. The most frequently used part in herbal medicines is the leaf, followed by the stem and root. People sometime use animal parts, soil, salt and water from a grass roof, in traditional medicines. Herbal medicines are stored for short periods of time in bottles. The knowledge to treat ailments is acquired from parents and grandparents. Respondents' age and tribe appears to have a significant influence on knowledge of herbal medicine, while gender does not. CONCLUSION: This survey has indicated that IK associated with TM stills exists and that TM is still important in Uganda because many people use it as a first line of health care when they fall sick. Age and tribe influence the level of IK associated with herbal medicine, but gender does not.     

Glutamine synthetase in the phloem plays a major role in controlling proline production

To inhibit expression specifically in the phloem, a 274-bp fragment of a cDNA (Gln1-5) encoding cytosolic glutamine synthetase (GS1) from tobacco was placed in the antisense orientation downstream of the cytosolic Cu/Zn superoxide dismutase promoter of Nicotiana plumbaginifolia. After Agrobacterium-mediated transformation, two transgenic N. tabacum lines exhibiting reduced levels of GS1 mRNA and GS activity in midribs, stems, and roots were obtained. Immunogold labeling experiments allowed us to verify that the GS protein content was markedly decreased in the phloem companion cells of transformed plants. Moreover, a general decrease in proline content in the transgenic plants in comparison with wild-type tobacco was observed when plants were forced to assimilate large amounts of ammonium. In contrast, no major changes in the concentration of amino acids used for nitrogen transport were apparent. A (15)NH(4)(+)-labeling kinetic over a 48-hr period confirmed that in leaves of transgenic plants, the decrease in proline production was directly related to glutamine availability. After 2 weeks of salt treatment, the transgenic plants had a pronounced stress phenotype, consisting of wilting and bleaching in the older leaves. We conclude that GS in the phloem plays a major role in regulating proline production consistent with the function of proline as a nitrogen source and as a key metabolite synthesized in response to water stress.     

Pheomelanin as a Binding Site for Drugs and Chemicals

Certain drugs and chemicals, such as chloroquine, chlorpromazine, and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), are bound to melanin and retained in pigment cells for long periods. This specific retention in pigmented tissues can cause adverse effects in the skin, eye, inner ear, and pigmented nerve cells of the substantia nigra of the brain. To date, all studies have been focused on eu- and neuromelanin. In the present study, we show that chloroquine, chlorpromazine, chlomipramine, paraquat, acridine orange, and nickel, which are bound to eumelanin, also bind to synthetic pheomelanin, but the binding to pheomelanin is lower. The binding varied with the cysteine content and pH, and the results indicate that the binding is complex and includes ionic interactions. In addition, we have shown that these substances also bind to synthetic thiourea-containing melanin, but to quite a low extent. We also present a microautoradiographic study on the binding of ¹⁴C-chloroquine to natural pheomelanin in vivo in yellow mice C57BL (A^y/a). Black (C57/BL) and albino (NMRI) mice were used as controls. The autoradiography demonstrated a pronounced uptake of chloroquine in the hair follicles and the dermal melanocytes in the ear of yellow mice, which was comparable to the corresponding accumulation of label in black mice. In the albino mouse, the uptake was lower and more homogeneously distributed in the skin. These results suggest that the toxicologi-cal risks of melanin-related adverse effects are applicable to persons with a high content of pheomelanin in the skin and hair.     

SV40 large T antigen is modified with O-linked N-acetylglucosamine but not with other forms of glycosylation

SV40 large T antigen has been reported to be modified with several different sugars including N-acetylglucosamine, galactose, and mannose. In this report we have reexamined the glycosylation of T antigen and found that while we could detect modification with N-acetylglucosamine, we could not detect any other sugars on the protein. Surprisingly, even though [3H]galactose could be metabolically incorporated into the protein, analysis showed that all of the radioactivity in T antigen had been converted to other species. The N-acetylglucosamine was demonstrated to be linked to the protein in the form of O-linked N- acetylglucosamine, the best characterized form of nuclear and cytoplasmic glycosylation in mammalian systems. We have localized the major site of glycosylation to the amino terminal portion of the molecule. Analysis of mutated T antigen where serines 111/112 were substituted with alanine suggest that these residues constitute a glycosylation site on the protein. These two serines fall within a typical O-linked N-acetylglucosamine glycosylation site (PSS) and are also known to be phosphorylated. Thus, it is likely that competition between phosphorylation and glycosylation occurs at this site.      

Docking studies on novel analogues of 8 methoxy fluoroquinolones against GyrA mutants of Mycobacterium tuberculosis

Background

Modeling of transmembrane domains (TMDs) requires correct prediction of interfacial residues for in-silico modeling and membrane insertion studies. This implies the defining of a target sequence long enough to contain interfacial residues. However, too long sequences induce artifactual polymorphism: within tested modeling methods, the longer the target sequence, the more variable the secondary structure, as though the procedure were stopped before the end of the calculation (which may in fact be unreachable). Moreover, delimitation of these TMDs can produce variable results with sequence based two-dimensional prediction methods, especially for sequences showing polymorphism. To solve this problem, we developed a new modeling procedure using the PepLook method. We scanned the sequences by modeling peptides from the target sequence with a window of 19 residues.

Results

Using sequences whose NMR-structures are already known (GpA, EphA1 and Erb2-HER2), we first determined that the hydrophobic to hydrophilic accessible surface area ratio (ASAr) was the best criterion for delimiting the TMD sequence. The length of the helical structure and the Impala method further supported the determination of the TMD limits. This method was applied to the IL-2Rβ and IL-2Rγ TMD sequences of Homo sapiens, Rattus norvegicus, Mus musculus and Bos taurus.

Conclusions

We succeeded in reducing the variation in the TMD limits to only 2 residues and in gaining structural information.     

Microbial controls on DMSP degradation and DMS formation in the Sargasso Sea

Bacterial degradation of dimethylsulfoniopropionate (DMSP) represents one of the main sources of the climatically–active trace gas dimethylsulfide (DMS) in the upper ocean. Short-term enrichment studies to stimulate specific pathways of DMSP degradation in oligotrophic waters from the Sargasso Sea were used to explore regulatory connections between the different bacterial DMSP degradation steps and determine potential biological controls on DMS formation in the open ocean. Experiments were conducted with surface water at the BATS station in the western North Atlantic Ocean. We added selected organic substrates (25 nmol L^?1 final concentration) to induce different steps of DMSP degradation in the microbial community, and then measured DMSP dynamics (assimilation and turnover rates), DMS yields (using ³⁵sulfur-DMSP tracer), and bacterial production rates. In most treatments, the main fate of consumed S-DMSP was excretion as a non-volatile S product. ³⁵S-DMSP tracer turnover rates (accumulation + assimilation + excretion of transformed products as DMS or others) increased upon addition of DMSP and glucose, but not acrylate, methymercaptopropionate (MMPA), methanethiol, DMS or glycine betaine. DMS yields from ³⁵S-DMSP never exceeded 16 % except in a short term DMSP enrichment, for which the yield reached 45 % (±17 %). Results show that availability of non-sulfur containing labile C sources (glucose, acrylate) decreased bacterial DMS production while stimulating bacterial heterotrophic production, and suggest an influence of bacterial sulfur demand in controlling DMS-yielding pathways. However, regulatory effects on ³⁵S-DMSP fate were not consistent across all reduced sulfur compounds (i.e., methanethiol or MMPA), and may reflect alternate roles of DMSP as a bacterial energy source and osmolyte.     

Calf thymus high mobility group proteins are nonenzymatically glycated but not significantly glycosylated

Over the past decade, there have been many reports suggesting the presence of complex carbohydrates on nuclear and cytoplasmic proteins in mammalian cells. Some of the most often cited of these reports deal with the glycosylation of the high mobility group (HMG) proteins. These are relatively abundant chromosomal proteins that are known to be associated with nucleosomes and actively transcribed regions of chromatin. The original report describing HMG protein glycosylation presented several lines of evidence suggesting that these proteins are glycosylated, including carbohydrate compositional analysis and periodic-acid Schiff staining. We have attempted to repeat these observations with more highly purified protein than was utilized in the original study. Using carbohydrate compositional analysis performed by high pH anion exchange chromatography coupled to pulsed-amperometric detection, we saw no evidence for significant glycosylation of these proteins. In addition, we found no evidence for the presence of O- GlcNAc, a well known form of nuclear glycosylation. The HMG proteins did react with periodate, suggesting the presence of a modification containing cis-diols on the protein. Several tryptic peptides isolated from HMG 14 and 17 which retained the periodate reactivity had in common lysine residues, suggesting a potential modification of the straightepsilon-amino groups of lysines such as nonenzymatic glycation. Western blot analysis of the HMG proteins using anti-advanced glycation endproducts (AGE) antibodies confirmed the presence of glycation products on the HMG proteins.