Showing papers on "Blisters published in 1982"

Frost Blisters of the Bear Rock Spring Area near Fort Norman, N.W.T.

Abstract: Frost mounds of the frost blister type form every winter at the site of a group of cold mineralized springs on the east side of Bear Rock near Fort Norman, Northwest Territories, Canada. During each of four years of observation (1975-1978) three to five frost blisters formed, with measured heights ranging from 1.4 to 4.9 m, and with horizontal dimensions between 20 and 65 m. Locations of the blisters varied somewhat, presumably in response to differences in temperature regime and snow cover. Mature frost blisters consisted of a layer of frozen ground ... and a layer of ice ... covering a cavity which in some cases was over 4.0 m high. The cavities contained water during formation of the frost blisters; they were empty by spring. Time-lapse photography revealed that frost blisters can grow as fast as 0.55 m/d, and that some of them fracture, drain and partially subside one or more times before reaching their full height. During the summer, degradation occurs as a result of thawing and slumping of the soil cover and by melting and collapse of the ice layer; portions of the ice layer, or an uncollapsed section of a frost blister, can survive until the second summer after their formation. Water chemistry and isotope studies revealed that the frost blisters are formed by pressure build-up in subsurface water below seasonal frost and that the ice layers accumulate by gradual downward freezing in a closed (or intermittently opened) system filled with water derived from the Bear Rock spring system. Similar frost blisters are found in other areas of groundwater discharge in a variety of locations. Key words: frost blisters, hydraulic uplift, springs, icings, permafrost, environmental isotopes, time-lapse photography

System for monitoring the operation of a machine for producing blister packages or the like

Abstract: A preheated carrier strip of thermoplastic material passes successively through a molding station in which blisters are formed therein, a filling station in which goods to be packaged are introduced into these blisters, a sealing station in which a metallic cover strip is fused onto the carrier strip for hermetically closing the filled blisters, and a cutting station in which the resulting composite tape is divided into individual packages each having one or more rows of blisters. The tape is positively entrained by the two transport rollers, which have peripheral indentations engaged by its blisters, and forms a loop of variable length between these rollers to allow for their instantaneous speed differences. A first photodetector scans the carrier strip between the filling and sealing stations and, on sensing an empty blister, causes the actuation of a perforator punching a hole into a part of the cover strip subsequently coming to overlie the incompletely filled row of blisters. An error pulse simultaneously loaded into a shift register actuates, after a suitable delay, a sorter downstream of the cutting station to eliminate the defective package from the regular machine output. A resulting control pulse, read out from an earlier stage of the shift register, causes the generation of an alarm signal if it does not coincide with a reference pulse from a second photodetector positioned to sense the punched hole between the downstream transport roller and the cutting station.

Basement membrane components and galactosylhydroxylysyl glucosyltransferase in suction blisters of human skin

Abstract: SUMMARY Basement membrane components and collagen biosynthesis were studied in suction blisters in human skin. The basement membrane components were characterized by immunofluorescence using specific antibodies to type IV collagen, laminin and fibronectin, and collagen biosynthesis was studied by assaying galactosylhydroxylysyl glucosyltransferase. In suction blisters, the separation of epidermis and dermis occurred above the lamina lucida, indicating that the basement membrane, composed of lamina lucida and lamina dcnsa, forms a mechanically strong entity. During the regeneration phase of blisters, type IV collagen and laminin were not observed in the old epidermal blister roof. This indicates that keratinocytes when separated from the underlying basement membrane or connective tissue do not synthesize laminin or type IV collagen. GalactosylhydroxylysyJ glucosyltransferase activity could be demonstrated in blister fluid and was about the same as in serum when expressed on the basis of protein in fresh blisters. It increased by 2–3 fold during the repair of blisters, indicating that there was local production of this enzyme. Further studies revealed that pure epidermis contained galactosylhydroxylysyl glucosyltransferase and hydroxyproline and this suggests that epidermis may synthesize some collagen type which, according to these studies, is not type IV (basement membrane) collagen.

Does cantharides blister fluid provide access to the peripheral compartment

Abstract: The pharmacokinetics of bendroflumethiazide (BFT) was investigated following the oral administration of 10 mg to 3 healthy volunteers. Each subject participated twice in the study. BFT was determined in plasma and cantharides blister fluid from 1/2 to 30 h post administration. Blister fluid was obtained from blisters 10–22 h old. Plasma levels were fitted to a tri-exponential equation and the concentration of the drug in the peripheral compartment was calculated from the microscopic rate constants. In 5 of 6 cases investigated, cantharides blister fluid levels paralleled the concentration of the drug in the peripheral compartment. The mean blister fluid levels exceeded the calculated concentration in Compartment 2 1.46 fold. In one case, the blister fluid level paralleled the plasma level. This subject clearly differed from the others as more than 10 h were required for blister formation in her. The results suggest that following the administration of BFT, cantharides blister fluid behaves as part of the peripheral compartment. The possible value of studying blister fluid levels in pharmacokinetic investigations is discussed.

The healing of suction blisters in pig skin

Abstract: The healing of intact suction blisters in pig skin was studied using fluorescein-labelled lectins as well as conventional histological techniques. After blistering, initially overt separation was observed at the dermo-epidermal junction, but the separated epidermis appeared to re-attach within 9 h. Massive infiltration of the dermis and the epidermis by inflammatory cells, including eosinophils, was observed. By day 4 focal detachment of the epidermis occurred spontaneously, and towards day 9 the appearance of the blistered areas had almost returned to normal, apart from isolated patches of thin epidermis devoid of rete ridges. It is proposed that the sloughing of the epidermis on day 4 is related to the presence of inflammatory cells and that the restoration of normal dermo-epidermal relations is dependent on the basement membrane zone remaining intact. The secondary blistering seen in day 4 specimens and the inflammatory cell involvement are in many ways similar to the blistering processes observed in certain human cutaneous disorders, such as dermatitis herpetiformis and bullous pemphigoid, and therefore suction blisters in pig skin might provide a suitable animal model for these diseases.

Helium bubble and blister formation for Ni and an amorphous Fe-Ni-Mo-B alloy during 5 keV implantation at 300 K

Abstract: Results are presented for helium bubble formation in Ni and amorphous Fe40Ni38Mo4Bl8 during 5 keV He-implantation at 300 K. The formation of helium blisters on the surface is also reported.

Immediate effect of ultraviolet‐B radiation on epidermal lysosomal hydrolases

Abstract: SUMMARY The immediate effect of ultraviolet-B radiation on epidermal lysosomal enzymes in vivo was studied by irradiating the roof of suction blisters. The activities of ten lysosomal hydrolases were determined in the blister fluid and in the epidermal homogenates. The enzyme values were decreased in the irradiated epidermis compared with the non-irradiated epidermis of control suction blisters, but the values found in the fluid of irradiated blisters were not decreased compared with control fluid.