NHS patients' perspective on complementary medicine: a survey.

OBJECTIVES: To examine patients' reasons for seeking complementary and alternative medicine (CAM) in the National Health Service, including the nature and duration of the patient's main health problem, the impact of CAM on this, satisfaction with clinical care, and usage of conventional prescription medication. DESIGN: Survey (n=499). SETTING: Out-patient Department, The Royal London Homeopathic Hospital, a National Health Service facility dedicated to CAM. RESULTS: Five hundred and six questionnaires were returned, 499 were analysed. Patients' most frequent reasons for seeking CAM were that other treatment had not helped, and concerns about or experience of adverse treatment reactions. Two hundred and ninety-seven patients (63%) had had their main problem for more than 5 years. Musculoskeletal system problems were the most frequent diagnostic group (n=151, 32%). Satisfaction with clinical care was high (443/490: 90%). Three hundred and eighty patients (81%) indicated their main problem had improved very much, moderately or slightly. Of the 262 patients who had been taking prescription medicines when they first attended, 76 (29%) had stopped, and 84 (32%) had reduced their intake. CONCLUSIONS: The results suggest that orthodox medicine is not meeting the needs of some patients and that CAM may wholly or partly substitute for conventional medicines. Most patients indicated their problem had improved with CAM. Implications for future research are discussed.

Evolution of a light-harvesting protein by addition of new subunits and rearrangement of conserved elements: crystal structure of a cryptophyte phycoerythrin at 1.63-A resolution.

Cryptophytes are unicellular photosynthetic algae that use a lumenally located light-harvesting system, which is distinct from the phycobilisome structure found in cyanobacteria and red algae. One of the key components of this system is water-soluble phycoerythrin (PE) 545 whose expression is enhanced by low light levels. The crystal structure of the heterodimeric alpha(1)alpha(2)betabeta PE 545 from the marine cryptophyte Rhodomonas CS24 has been determined at 1.63-A resolution. Although the beta-chain structure is similar to the alpha and beta chains of other known phycobiliproteins, the overall structure of PE 545 is novel with the alpha chains forming a simple extended fold with an antiparallel beta-ribbon followed by an alpha-helix. The two doubly linked beta50/beta61 chromophores (one on each beta subunit) are in van der Waals contact, suggesting that exciton-coupling mechanisms may alter their spectral properties. Each alpha subunit carries a covalently linked 15,16-dihydrobiliverdin chromophore that is likely to be the final energy acceptor. The architecture of the heterodimer suggests that PE 545 may dock to an acceptor protein via a deep cleft and that energy may be transferred via this intermediary protein to the reaction center.

Introducing complementary medicine into the medical curriculum.

We surveyed the deans of British medical schools to determine the provision of complementary medicine in the undergraduate curriculum. We also sampled medical students at one British medical school to determine their knowledge of, and views on instruction in, complementary medicine. There is little education in complementary medicine at British medical schools, but it is an area of active curriculum development. Students' levels of knowledge vary widely between different therapies. Most medical students would like to learn about acupuncture, hypnosis, homoeopathy and osteopathy. We conclude that complementary medicine should be included in the medical undergraduate curriculum. This could be done without a great increase in teaching of facts, and could serve as a vehicle to introduce broader issues, as recommended by the General Medical Council.

Two distinct forms of the peridinin-chlorophyll a-protein from Amphidinium carterae.

Peridinin-chlorophyll a-proteins (PCPs) have been purified by combination of ammonium sulphate precipitation and cation exchange chromatography. The amino acid sequences of several of the most abundant forms have been deduced by direct protein sequencing and from DNA and indicate a highly conserved multi-gene family. At least two of the PCP genes are tandemly arranged. A novel form of the protein was also obtained in low yield with fewer peridinins (six vs eight) per chlorophyll a and with a different molecular mass (34 kDa vs 32 kDa) of its apoprotein. It had only 31% sequence identity with any of the more abundant PCP forms but retained a two-domain structure.

Structural basis of light harvesting by carotenoids: peridinin-chlorophyll-protein from Amphidinium carterae.

Peridinin-chlorophyll-protein, a water-soluble light-harvesting complex that has a blue-green absorbing carotenoid as its main pigment, is present in most photosynthetic dinoflagellates. Its high-resolution (2.0 angstrom) x-ray structure reveals a noncrystallographic trimer in which each polypeptide contains an unusual jellyroll fold of the alpha-helical amino- and carboxyl-terminal domains. These domains constitute a scaffold with pseudo-twofold symmetry surrounding a hydrophobic cavity filled by two lipid, eight peridinin, and two chlorophyll a molecules. The structural basis for efficient excitonic energy transfer from peridinin to chlorophyll is found in the clustering of peridinins around the chlorophylls at van der Waals distances.

The light-harvesting chlorophyll a-c-binding protein of dinoflagellates: a putative polyprotein.

The principle light-harvesting chlorophyll a-c-binding protein of Amphidinium carterae of 19 kDa is encoded as a polyprotein translated from a 6.1 kb mRNA. The cDNA sequences indicate that each derived polypeptide is contiguous with the next and that the mature peptides are formed by cleavage at a C-terminal arginine residue. Comparison of the amino-acid sequences shows the Amphidinium protein to be most closely related to the fucoxanthin-chlorophyll-protein (Fcp) of Phaeodactylum and less related to the chlorophyll a-b-binding (Cab) proteins including those from Euglena.

Crystallization and preliminary X-ray analysis of a peridinin-chlorophyll a protein from Amphidinium carterae.

Crystals of a water-soluble (Mr approximately 39,000) peridinin-chlorophyll a protein from Amphidinium carterae are reported. The crystals diffract to 2.2 A and belong to a monoclinic (B2) and a triclinic (P1) space group. Spectra of the protein in the crystal and in solution are almost identical.

Spread of organisms with novel genotypes: thoughts from an ecological perspective.

One category of objection to the release of organisms produced by genetic engineering is based on the fear that such organisms may persist in the environment and damage existing ecosystems. An assessment of environmental risk thus involves an ecological question analogous to the introduction of exotic species which has been known to produce serious ecological disruptions. An investigation of the literature on exotic introductions reveals, however, that foreign species do not invariably produce adverse changes. Ecologists believe that only a fraction of immigrating species actually produces ecological dislocation while the majority probably fail to penetrate existing biotic assemblages. Stressed or simplified environments are, however, more vulnerable to successful invasion. Unfortunately, because very little information has ever been collected to document the number or causes of failed introductions, it is impossible to quantify the probability that any introduced species will or will not cause serious disturbance purely on the basis of historical evidence. The development and spread of genotypes that confer resistance to chemical control agents in insects and microorganisms is also analogous to genetic engineering in that human activity contributes to the spread of new genotypes. In both groups of organisms, resistant genotypes can come to predominate in even geographically widespread populations with great rapidity. Resistance to pesticides in insects is usually found to be determined by single genes. In bacteria, antibiotic resistance genes are usually, if not always, associated with the extrachromosomal genetic elements known as plasmids. Bacteria seem to be able to transmit plasmid-borne genes between species and genera with facility. The ease with which new genes can be inserted into bacteria via plasmid vectors in recombinant technology is thus a two-edged sword. It may be very difficult to keep inserted genes isolated in single bacterial strains. The evaluation of the literature on which this report is based suggests that an ecological approach for risk assessment is appropriate. Microorganisms, for which genetic engineering is of most immediate importance, exhibit the same ecological properties as higher organisms. The proportion of an organism's genome which is novel has no direct correlation with the magnitude of impact such a change may have in economic, medical, or ecological terms. Meaningful probabilities for persistence of engineered organisms in the environment will have to be generated by experiment, probably with model microbial ecosystems.

Relative flatness measurement of uncoated optical flats.

A method is described for measuring the relative flatness of uncoated precision optical flats to lambda/1000. The method uses scanning interferometry and can be made automatic fairly readily.