Biochemical and immunochemical analysis of the arrangement of connexin43 in rat heart gap junction membranes

A 43 × 10^3 M_r protein (designated connexin43 or Cx43) is a major constituent of heart gap junctions. The understanding of its arrangement in junctional membranes has been extended by means of site-directed antibodies raised against synthetic peptides of Cx43. These represent part of the first extracellular loop (EL-46), the cytoplasmic loop (CL-100), the second extracellular loop (EL-186) and carboxy-terminal sequences (CT-237 and CT-360). All of the antibodies raised reacted with their respective peptides and the Cx43 protein on Western blots. By immunoelectron microscopy two of the antibodies (CL-100 and CT-360) were shown to label the cytoplasmic surface of isolated gap junction membranes. Immunofluorescent labeling at locations of neonatal cardiac myocyte-myocyte apposition required an alkali/urea treatment when the EL-46 and EL-186 antibodies were used. Immunoblot analysis of endoproteinase Lys-C-digested gap junctions revealed that the Cx43 protein passed through the lipid bilayer four times. Alkaline phosphatase digestion of isolated junctions was used to show that the CT-360 antibody recognized many phosphorylated forms of Cx43. Our results unequivocally confirm models of the organization of Cx43 that were based on a more limited set of data and a priori considerations of the sequence

Periglacial Features From Morfee Mountain, North-Central British Columbia

Six periglacial features (sorted polygons, sorted steps, sorted nets, sorted stripes, sorted circles, felsenmeer and a possible altiplanation terrace) are described from a new location in Central British Columbia (locally known as Morfee Mountain, 55 deg. 26 sec. N, 123 deg. 02 sec. W) between 1300-1650 m elevation. These features are local in distribution over an area of several square km. Observations on specific features indicate a continuum of intermediate forms between sorted nets, sorted polygons and sorted stripes. The elevation of these features supports the suggestion of Brown and Pewe (1973) that the lower elevation of permafrost and periglacial features should rise progressively southward along a north-south transect through the Western Cordillera

A Rare Form of Silene acaulis L. (moss Campion) from British Columbia

While conducting an Ecological Reserves survey of Morfee Mountain in North Central British Columbia (55° 26' N, 123° 04' W) during mid-July 1971, the author noted an interesting variation of flower colour in Silene acaulis L. subsp. subacaulescens (F.N. Williams) Hult. The flower colours of Silene acaulis are usually purple, pink or lavender throughout its range. The majority of the individuals of this species on Morfee Mountain conformed to the usual flower colour. However, one individual plant with pure white petals was observed .... The specimen was collected near the British Columbia Telephone Company microwave relay station on Morfee Mountain at an elevation of about 1700 m. ... Although the white-flowered form of Silene acaulis is not unknown, Hultén (1968) notes that this form is rare, thus making the find an interesting observation for both the amateur botanist and the more serious student of intraspecific variation in plants

Northern Canadian Gardening: Compost Piles as a Means of Extending the Growing Range of Northern Crops

... The use of compost piles for growing frost-sensitive crops with long growing seasons holds considerable promise as a technique for northern domestic gardening, incorporating the benefits of direct garden seeding with those of conventional hot beds. The owners of most of the 50 gardens examined in Dawson in 1980 (McCracken and Revel, 1982) composted organic wastes, though none of them used compost piles for crop production. The abundance of compost piles and the successful growth of the volunteer cucumbers we observed suggests that this technique could be widely used throughout the north by those who wish to grow warmer-climate crops without a greenhouse, and without the need for bedding-out plants

Domestic and Commercial Vegetable Gardening in Dawson City, Yukon Territory, 1980

Canadian subarctic agriculture has not been a widespread practice. Because of increasing northern populations associated with industrial development, and the high cost of fresh produce, the practicality and success of subarctic gardening are examined. Dawson City was chosen for study because of its long history of gardening. In 1980 there were 50 domestic gardens, 56 greenhouses, and three commercial gardens which supplied produce both locally and to Whitehorse and Inuvik. The study documents the following crops: cabbage, cauliflower, broccoli, Brussels sprouts, carrots, turnips, kohlrabi, radish, beans, peas, potatoes, lettuce, kale, beetroot, Swiss chard, celery, onions, cucumber, tomatoes, zucchini, corn, peppers, leeks, squash, sunflowers and a large variety of herbs. The specific crop varieties used by gardeners are noted along with observations on their relative success, planting and harvesting dates and special gardening practices.Key words: agriculture, gardening, vegetable cultivationMots clés: agriculture, jardinage, culture de légume

Interferon Beta 2/Interleukin-6 and Interleukin-3 Synergize in Stimulating Proliferation of Human Early Hematopoietic Progenitor Cells.

Early 4-hydroxyperoxycyclophosphamide (4-HC) resistant hematopoietic progenitor cells (pre-colony-forming units, pre-CFU) were evaluated by a two-step liquid culture system, (earlier progenitors), pre-CFU, as well as by the conventional semi-solid mixed colony assay (later progenitors) for their growth response to interleukin-6 (IL-6), interleukin-3 (IL-3), and a combination of both factors. The effect of the IL-6/IL-3 combination was compared to that of IL-1/IL-3. IL-3 alone proved less effective in supporting earlier pre-CFU cells than later progenitor cells. In a previous work IL-6 promoted the growth of early multipotential progenitor cells circulating in hairy cell leukemia (HCL) patients. IL-6 alone did not stimulate growth of either early or later normal progenitor cells. However, a significant synergistic effect was obtained when IL-6 and IL-3 were added together (p \u3c0.05). IL-6/IL-3 synergism was more potent than IL-1/IL-3 in promoting growth of colonies. The previously described synergistic effect of IL-1/IL-3 seems to be independent of IL-6. Thus, our results suggest that the multifunctional cytokine IL-6, may be of use in shortening the engraftment time in bone marrow transplantation