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Ma̅nuka honey is known for its strong bioactivity, which arises from the autocatalytic conversion of 1,3-dihydroxyacetone (dihydroxyacetone, DHA) in the floral nectar of Leptospermum scoparium(Myrtaceae) to the non-peroxide antibacterial compound methylglyoxal during honey maturation. DHA is also a minor constituent of the nectar of several other Leptospermumspecies. This study used high-performance liquid chromatography to test whether DHA was present in the floral nectar of five species in other genera of the family Myrtaceae: Ericomyrtus serpyllifolia(Turcz.) Rye, Chamelauciumsp. Bendering (T.J. Alford 110), Kunzea pulchella(Lindl.) A.S. George, Verticordia chrysanthaEndl., and Verticordia pictaEndl. DHA was found in the floral nectar of two of the five species: E. serpyllifoliaand V. chrysantha. The average amount of DHA detected was 0.08 and 0.64 μg per flower, respectively. These findings suggest that the accumulation of DHA in floral nectar is a shared trait among several genera within the family Myrtaceae. Consequently, non-peroxide-based bioactive honey may be sourced from floral nectar outside the genus Leptospermum.

Objective: To review clinical data on the use of long-acting bronchodilator agents as monotherapy and in combination for the treatment of moderate-to-severe chronic obstructive pulmonary disease (COPD).Data Sources: A literature search was performed via MEDLINE (1966–April 2008). In addition, references from publications identified were reviewed. These searches were limited to human data published in the English language. Searches used the following terms: COPD, long-acting β2-agonisls, long-acting anticholinergics, combination therapy, pharmacoeconomics, safety, tiotropium, salmeterol, and formoterol.Study Selection and Data Extraction: Relevant information on the pharmacology, safety, efficacy, pharmacoeconomics, adherence, and available agents used in the treatment of COPD was selected. Randomized clinical trials and retrospective reviews were included.Data Synthesis: The Global Initiative for Chronic Obstructive Lung Disease guidelines provide general management recommendations to guide providers regarding treatment choices for COPD; however, they lack clarity regarding which long-acting bronchodilator to use and when combining agents becomes appropriate. Prospective trials evaluating short-acting anticholinergics and long-acting β2-agonists have utilized spirometric endpoints that relate most to short-term symptomatic relief. Tiotropium trials have focused more on patient-oriented outcomes, with data being reported for one year. Tiotropium significantly lowers exacerbation rates and improves health resource usage as well as health-related quality of life. Tiotropium also provides superior bronchodilation and improvement in dyspnea at all timo points, although onset of bronchodilation is slower than with long-acting β2-agonists. Combining these agents has been shown to decrease daytime rescue inhaler use, improve morning and evening peak expiratory flow rates, and improve bronchodilator efficacy compared with monotherapy. Pharmacoeconomic data lend support to the recommendation of tiotropium as a first-line long-acting agent.Conclusions: Tiotropium appears to be the best option as a first-line drug for patients with moderate-to-severe COPD because of its ability to sustain bronchodilator effect, improve quality of life, reduce COPD exacerbations, and reduce health resource usage. Patients who remain symptomatic may benefit from the addition of a long-acting β2-agonist to tiotropium monotherapy.

OBJECTIVE: To review data concerning combined angiotensin-converting enzyme (ACE) inhibitor and angiotensin II receptor blocker (ARB) therapy for hypertension.DATA SOURCES: MEDLINE (1966–April 2003), IPA (1970–April 2003), and EMBASE (1974–April 2003) with search terms of ACE inhibitor, angiotensin receptor blocker, essential hypertension, and combination therapy.DATA SYNTHESIS: ACE inhibitors provide incomplete blockade of the renin–angiotensin system, sometimes leading to loss of blood pressure control. Addition of ARBs may in theory further reduce blood pressure. Studies of combined ACE inhibitor and ARB therapy for managing hypertension were evaluated.CONCLUSIONS: While studies have shown statistically significant blood pressure reductions with ACE/ARB combination therapy, clinical significance is lacking. Further trials are needed before routine use of the combination can be recommended.

The alternative oxidase is found in the inner mitochondrial membranes of plants and some fungi and protists. A monoclonal antibody raised against the alternative oxidase from the aroid lily Sauromatum guttatumhas been used extensively to detect the enzyme in these organisms. Using an immunoblotting strategy, the antibody binding site has been localised to the sequence RADEAHHRDVNH within the soybean alternative oxidase 2 protein. Examination of sequence variants showed that A2 and residues C‐terminal to H7 are required for recognition by the monoclonal antibody raised against the alternative oxidase. The recognition sequence is highly conserved among all alternative oxidase proteins and is absolutely conserved in 12 of 14 higher plant sequences, suggesting that this antibody will continue to be extremely useful in studying the expression and synthesis of the alternative oxidase.

A rabbit antiserum was raised against phosphoenolpyruvate carboxykinase (PCK) purified from Urochloa panicoides, a PCK-type C4 monocot. The antiserum was used to screen a cDNA expression library constructed from U. panicoides leaf poly(A)+RNA. Inserts from immunoreactive clones were used to rescreen the library and obtain three overlapping cDNAs comprising a 2220 bp composite sequence. The single complete open reading frame of 1872 bp encodes PCK1, a 624 amino acid polypeptide with a predicted molecular mass of 68474 Da. Comparison of PCK1 with other ATP-dependent PCKs indicates that PCK1 is significantly larger, mainly due to an N-terminal extension of greater than 65 residues, and reveals high sequence identity across the central portion of the protein, especially over seven sub-sequences. One of these sub-sequences spans motifs common to several ATP-utilising enzymes for phosphate and divalent cation binding. The anti-PCK antiserum recognises a 69 kDa polypeptide on immunoblots of either purified PCK or U. panicoides leaf extracts. However, polypeptides of 63, 62, 61 and 60 kDa are also immunoreactive. Amino terminal sequencing of polypeptides from preparations of purified PCK demonstrates that these smaller polypeptides are related to PCK1, and time course experiments show that these polypeptides arise from the breakdown of PCK during isolation. Northern blot analysis indicates that the 2.7 kb PCK mRNA is abundant in green leaves but not in roots or etiolated shoots. Moreover, PCK mRNA levels increase gradually during greening, reaching maximum levels after about 84 h.

The nucleotide sequence of the yeast nuclear AEP2gene, required for the expression of the mitochondrial DNA-encoded subunit 9 of ATP synthase, predicts a primary translation product of 67.5 kDa. The ATP13gene is allelic to AEP2but was reported to encode a protein of about 42 kDa in size. We thus investigated genetically and biochemically the size of the AEP2gene product. Genetic complementation assays using 3′ truncated AEP2genes, here shows that function is abolished by the removal of only 32 amino acids from the C-terminus of the predicted protein product. Cell-free translation of AEP2produces a 64 kDa polypeptide (consistent with the AEP2sequence) which is imported into mitochondria and processed to a 58 kDa product by the removal of a presequence of about 50 amino acids.

A 66 kDa protein, denoted P66, not hitherto classified as an integral component of yeast mitochondrial ATPase, is often observed in preparations of this enzyme complex. A physical association exists between P66 and the assembled ATPase complex since both components are coimmunoprecipitated by anti-F 1β monoclonal antibody. Two recombinant clones expressing proteins immunologically similar to P66 were isolated from a yeast genomic library in λgt11 by screening with a polyclonal anti-holo-ATPase antibody. Based on restriction site mapping and partial nucleotide sequence analysis, both clones encompass the gene encoding the yeast heat shock protein hsp60. The identification of P66 with hsp60, taken together with its demonstrated association with the mitochondrial ATPase complex, is consistent with recent suggestions that hsp60 is involved in assembly of the ATP synthase complex.

A 66 kDa protein, denoted P66, not hitherto classified as an integral component of yeast mitochondrial ATPase, is often observed in preparations of this enzyme complex. A physical association exists between P66 and the assembled ATPase complex since both components are coimmunoprecipitated by anti‐F1β monoclonal antibody. Two recombinant clones expressing proteins immunologically similar to P66 were isolated from a yeast genomic library in λgt11 by screening with a polyclonal anti‐holo‐ATPase antibody. Based on restriction site mapping and partial nucleotide sequence analysis, both clones encompass the gene encoding the yeast heat shock protein hsp60. The identification of P66 with hsp60, taken together with its demonstrated association with the mitochondrial ATPase complex, is consistent with recent suggestions that hsp60 is involved in assembly of the ATP synthase complex.

Mitochondria isolated from maize plants with S-type male-sterile cytoplasms are capable of synthesizing four species of RNA at concentrations of actinomycin D that eliminate all DNA-directed RNA synthesis. No RNA synthesis occurs under the same conditions with mitochondria from plants possessing normal (N) cytoplasm or with other subcellular fractions from plants with S cytoplasm. The actinomycin D-resistant RNA synthesis occurs within the mitochondria since the labeling of these species is unaffected by inclusion of RNase in the incubation medium and since they become completely sensitive to RNase upon lysis of the mitochondria with low concentrations of Triton X-100. Two of the actinomycin D-resistant products are double stranded. These are 2850 and 900 base pairs in length, whereas the remaining two are 2150 and 850 bases. The synthesis of all four RNAs occurs in at least five different accessions of S cytoplasm, suggesting it is a general feature of S mitochondria. The double-stranded RNAs show homology to single-stranded S mitochondrial RNA but not to N mitochondrial RNA. Our observations indicate that the replication of these RNAs occurs independently of mtDNA and that they thus represent a novel type of inheritable element in organelles, an RNA plasmid.

The alternative oxidase (AOX) is the terminal oxidase that comprises the cyanide-resistant respiratory pathway in plant mitochondria. While the role of AOX in plant thermogenesis is well established, its role in the reproductive development of non-thermogenic species is not well understood. AOXgenes can be separated into two groups based on sequence homology, AOX1and AOX2. Reverse genetic experiments carried out primarily in Arabidopsis and tobacco have largely focussed on examining the role of AOX1-type genes in stress responses. We recently reported a systematic characterisation of the reproductive phenotypes of three AOX2 antisense lines of soybean. This addendum summarises the key evidence in our recent paper that points to a role for AOX in the development and function of both male and female gametophytes. Furthermore, we discuss the relative importance of AOX in the reproductive biology of plant species examined to date and highlight practical implications of our findings to crop improvement research.