Polyphenolics of Salvia--a review.

Salvia is an important genus widely cultivated and used in flavouring and folk medicines. The genus has attracted great interest so much so that it has been the subject of numerous chemical studies. It is a rich source of polyphenols, with an excess of 160 polyphenols having been identified, some of which are unique to the genus. A large number of these polyphenolic compounds are apparently constructed from the caffeic acid building block via a variety of condensation reactions. The nature of these polyphenols which have been reported is compiled in this report together with some bioactivity data in an effort to show the rapid development in the phytochemistry and the therapeutic applications of the Salvia species.     

Ultrastructure of Sertoli-cell penetrating processes found in germ cells of the golden-mantled ground squirrel (spermophilus lateralis)

We have studied the ultrastructure of Sertoli-cell processes that extend into developing germ cells of the ground squirrel (Spermophilus lateralis). In other mammals it is speculated that these processes anchor germ cells to the seminiferous epithelium and transfer materials between Sertoli and germ cells. In the ground squirrel, Sertoli-cell projections first appear in round spermatids and consist of regions containing numerous mitochondria and intermediate filaments together with areas composed mainly of a fine filamentous matrix. Also present are what may be desmosomelike junctions with adjacent germ cells. During spermatogenesis, numerous changes in the penetrating processes and their internal composition occur. Especially significant are those occurring during the movement of residual cytoplasm basally over spermatid heads: some Sertoli-cell processes contain microtubules, mitochondria, and vesicular elements, but also present are regions that lack organelles and appear simply as thin lamellae of cytoplasm that line cavernous invaginations of the germ cell. Coated vesicles and pits are present in processes and adjacent germ-cell regions at all stages of spermatogenesis. Our observations are consistent with the suggestions that Sertoli-cell processes have an attachment function and that they also may facilitate the movement of residual cytoplasm into the epithelium. Further, they indicate that these structures might be involved with receptor-mediated edocytosis.     

Use of photoaffinity probes containing poly(ethylene glycol) spacers for topographical mapping of the cholecystokinin receptor complex

To further define the structure of the pancreatic cholecystokinin (CCK) receptor and the topographical distance relationships between its subunits, we developed a series of monofunctional photoaffinity probes in which a fixed receptor-binding domain was separated from a photolabile nitrophenylacetamido group by defined lengths of a flexible spacer. The well-characterized CCK receptor radioligand 125I-D-Tyr-Gly-[(Nle28,31)CCK-26-33] provided the receptor-binding component of the probes, while the polymer poly(ethylene glycol) (2, 4, 7, and 10 monomer units long) was used as the spacer. The patterns of affinity labeling of rat pancreatic plasma membranes were examined as a function of spacer length. This ranged from 7.3 to 16.2 A, as calculated by root-mean-square end-to-end distances and validated experimentally by time-resolved fluorescence resonance energy transfer measurements. All probes in the series specifically labeled the Mr = 85,000-95,000 glycoprotein with Mr = 42,000 core, which has been proposed to contain the hormone recognition site. In addition, when the spacer length reached 16.2 A, membrane proteins of Mr = 80,000 and Mr = 40,000 were specifically labeled. The product of endo-beta-N-acetylglucosaminidase F digestion of the Mr = 80,000 protein was Mr = 65,000, similar to a protein previously identified in affinity labeling experiments using a CCK-33-based probe. These observations are consistent with the Mr = 85,000-95,000 pancreatic protein representing the hormone-binding subunit of the CCK receptor, while proteins of Mr = 80,000 and Mr = 40,000 may represent noncovalently associated subunits sited within 16.2 A of the binding domain.(ABSTRACT TRUNCATED AT 250 WORDS)     

Promotion of tumor growth by transfecting antisense DNA to suppress endogenous H-2Kk MHC gene expression in AKR mouse thymoma

Many AKR spontaneous thymomas are reported to express different amounts of the major histocompatibility complex class I H-2Kk molecules. Moreover, H-2Kk-deficient AKR tumor cells are found to be more malignant when compared to tumor cells that express abundant levels of the H-2Kk molecules. To corroborate further the role of H-2Kk in tumorigenesis of AKR leukemia, we have, in this study, expressed antisense H-2Kk RNA in a high-H-2Kk-expressing and poorly tumorigenic AKR thymoma cell line 369. The down-regulation of H-2Kk molecules in the transfected 369 clones rendered them more tumorigenic in syngeneic AKR/J mice. The increase in oncogenicity correlates well with a concomitant reduction in their susceptibility to tumor-specific cytotoxic T lymphocytes in vitro. These results suggest the relevance of H-2Kk molecules in the immune surveillance of AKR tumors.     

A Simplified Geometric Model to Predict Nasal Spray Deposition in Children and Adults

A mathematical approach was developed to estimate spray deposition patterns in the nasal cavity based on the geometric relationships between the emitted spray plume and the anatomical dimensions of the nasal valve region of the nasal cavity. Spray plumes were assumed to be spherical cones and the nasal valve region was approximated as an ellipse. The effect of spray plume angle (15–85°) on the fraction of the spray able to pass through the nasal valve (deposition fraction) was tested for a variety of nasal valve (ellipse) shapes and cross-sectional areas based on measured dimensions from pediatric and adult nasal cavities. The effect of the distances between the tip of the nasal spray device and the nasal valve (0.2–1.9 cm) on the deposition fraction was also tested. Simulation results show that (1) decreasing spray plume angles resulted in higher deposition fractions, (2) deposition fraction was inversely proportional to the spray distance and the nasal valve (ellipse) major/minor axis ratio, and (3) for fixed major/minor axis ratios, improved deposition occurred with larger nasal valve cross-sectional areas. For a typical adult nasal valve, plume angles of less than 40° emitted from a distance of 1 cm resulted depositions greater than 90% within the main nasal cavity, whereas for a 12-year-old child, only the most narrow plume angles (<?20°) administered resulted in significant deposition beyond the nasal valve.     

Kernel Architecture of the Genetic Circuitry of the Arabidopsis Circadian System

A wide range of organisms features molecular machines, circadian clocks, which generate endogenous oscillations with ~24 h periodicity and thereby synchronize biological processes to diurnal environmental fluctuations. Recently, it has become clear that plants harbor more complex gene regulatory circuits within the core circadian clocks than other organisms, inspiring a fundamental question: are all these regulatory interactions between clock genes equally crucial for the establishment and maintenance of circadian rhythms? Our mechanistic simulation for Arabidopsis thaliana demonstrates that at least half of the total regulatory interactions must be present to express the circadian molecular profiles observed in wild-type plants. A set of those essential interactions is called herein a kernel of the circadian system. The kernel structure unbiasedly reveals four interlocked negative feedback loops contributing to circadian rhythms, and three feedback loops among them drive the autonomous oscillation itself. Strikingly, the kernel structure, as well as the whole clock circuitry, is overwhelmingly composed of inhibitory, rather than activating, interactions between genes. We found that this tendency underlies plant circadian molecular profiles which often exhibit sharply-shaped, cuspidate waveforms. Through the generation of these cuspidate profiles, inhibitory interactions may facilitate the global coordination of temporally-distant clock events that are markedly peaked at very specific times of day. Our systematic approach resulting in experimentally-testable predictions provides insights into a design principle of biological clockwork, with implications for synthetic biology.     

$1 DNA barcodes for reconstructing complex phenomes and finding rare species in specimen‐rich samples

Several of the biggest challenges in taxonomy and systematics are related to a toxic mixture of small size, abundance, and rarity. There are too many species in groups with too few taxonomists and many of these species are very rare and hard to find because they are hidden in mass samples. To make matters worse, these species often have life‐history stages that are morphologically so different that it is difficult to identify them as semaphoronts of the same species. We demonstrate that these biodiversity challenges can be addressed with cost‐effective molecular markers. Here, we describe a next‐generation‐sequencing protocol that can yield barcodes at a chemical cost of < 0.40 USD per specimen. We use this protocol to generate molecular markers for 1015 specimens of tropical midges (Diptera: Chironomidae). The barcodes cluster into 52–61 molecular operational taxonomic units (OTUs) depending on whether Objective Clustering (OC), Generalized Mixed Yule Coalescent (GMYC), or Poisson Tree Process (PTP) is used. More than half of the putative species are rare (< 10 specimens) and we are able to match larvae and adults for 24 of these OTUs. We argue that the proposed protocol will help with processing specimen‐rich biodiversity samples at low cost.     

Continuing to Confront COPD International Patient Survey: Economic Impact of COPD in 12 Countries

BackgroundThe Continuing to Confront COPD International Patient Survey estimated the prevalence and burden of COPD across 12 countries. Using data from this survey we evaluated the economic impact of COPD.MethodsThis cross-sectional, population-based survey questioned 4,343 subjects aged 40 years and older, fulfilling a case definition of COPD based on self-reported physician diagnosis or symptomatology. Direct cost measures were based on exacerbations of COPD (treated and those requiring emergency department visits and/or hospitalisation), contacts with healthcare professionals, and COPD medications. Indirect costs were calculated from work loss values using the Work Productivity and Activity Impairment scale. Combined direct and indirect costs estimated the total societal costs per patient.ResultsThe annual direct costs of COPD ranged from $504 (South Korea) to $9,981 (USA), with inpatient hospitalisations (5 countries) and home oxygen therapy (3 countries) being the key drivers of direct costs. The proportion of patients completely prevented from working due to their COPD ranged from 6% (Italy) to 52% (USA and UK) with 8 countries reporting this to be ≥20%. Total societal costs per patient varied widely from $1,721 (Russia) to $30,826 (USA) but a consistent pattern across countries showed greater costs among those with increased burden of COPD (symptoms, health status and more severe disease) and a greater number of comorbidities.ConclusionsThe economic burden of COPD is considerable across countries, and requires targeted resources to optimise COPD management encompassing the control of symptoms, prevention of exacerbations and effective treatment of comorbidities. Strategies to allow COPD patients to remain in work are important for addressing the substantial wider societal costs.     

Analysis of hybrid H-2D and L antigens with reciprocally mismatched aminoterminal domains: functional T cell recognition requires preservation of fine structural determinants

Studies of immune recognition of hybrid class I antigens expressed on transfected cells have revealed an apparent general requirement that the N(alpha 1) and C1(alpha 2) domains be derived from the same gene in order to preserve recognition by virus-specific H-2-restricted and allospecific T cells. One exception has been the hybrid DL antigen in which the N domain of H-2Ld has been replaced by that of H-2Dd. Cells bearing this molecule serve as targets for some virus and allospecific CTL. Because cells expressing the reciprocal hybrid LD (N domain of H-2Dd replaced by that of H-2Ld) antigen have not been available, it has not been possible to evaluate whether this exception stemmed from the relatedness of H-2Ld and H-2Dd or whether the DL antigen fortuitously preserved some function of the parent molecule as a rare exception. To assess this question, and to evaluate the contribution of the N and C1 domains of H-2Ld and H-2Dd to serologic and T cell recognition, we have constructed the reciprocal chimeric gene pLD (the N exon of H-2Ld substituted for that of H-2Dd), introduced this into mouse L cells by DNA-mediated gene transfer, and analyzed the expressed product biochemically, serologically, and functionally. Transformant L cells expressing either LD or DL antigens were both reactive with a number of anti-H-2Ld or anti-H-2Dd N/C1-specific monoclonal antibodies, indicating the preservation in the hybrid molecules of determinants controlled by discrete domains. Mab binding was generally greater with cells expressing hybrid DL antigen than with those transformants expressing LD molecules. Moreover, the amount of beta 2M associated with DL antigens was more than that associated with LD. Cells expressing hybrid DL antigens were recognized as targets by bulk and cloned allospecific anti-H-2Dd and anti-H-2Ld CTL, whereas cells expressing LD molecules were not recognized by any of the T cells tested. VSV-specific H-2Ld-restricted CTL failed to lyse VSV-infected targets expressing either DL or LD. These results indicate that T cell reactivity of cells expressing the DL hybrid antigen is an exception to the observed general requirement for class I antigens to possess matched N and C1 domains for functional T cell recognition by T cells restricted to parental antigens.(ABSTRACT TRUNCATED AT 400 WORDS)