PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Cold Chain”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources

Mechanism for adaptive modification during cold acclimation of phospholipid acyl chain composition in Tetrahymena. II. Activities of 2-acyl-sn-glycerol-3-phosphorylcholine and 2-acyl-sn-glycerol-3- phosphorylethanolamine acyltransferases involving the reacylation.

The deacylation-reacylation process is very important for the alteration of phospholipid fatty acyl composition on lowering of growth temperature in Tetrahymena pyriformis (Kameyama, Y., Yoshioka, S. and Nozawa, Y., (1984) Biochim. Biophys. Acta 793, 28-33). Microsomes isolated from Tetrahymena cells have reacylation activities not only for 1-acyl-sn-glycerol-3-phosphorylcholine (1-acyl-GPC) and 1-acyl-sn-glycerol-3-phosphorylethanolamine (1-acyl-GPE) but also for 2-acyl-GPC and 2-acyl-GPE. Unsaturated fatty acyl-CoAs were in general much better substrates than saturated fatty acyl-CoAs for acylations of 1-acyl-GPC and 1-acyl-GPE. The acylation rates for 1-acyl-GPE were almost the same in palmitoleoyl-CoA, oleoyl-CoA, linoleoyl-CoA and gamma-linoleoyl-CoA. However, the acylation activity for 1-acyl-GPC was more than 2-fold higher with palmitoleoyl-CoA than with any other unsaturated fatty acyl-CoAs. In contrast, both 2-acyl-GPC and 2-acyl-GPE acyltransferases did not show a distinct preference for various acyl-CoAs, although palmitoyl-CoA was incorporated into both 2-acylphospholipids at higher rates than into 1-acylphospholipids. These specificities for various acyl-CoAs of 1-acyl- and 2-acyl-GPC and 1-acyl- and 2-acyl-GPE acyltransferases were not changed in the microsomes isolated from cells grown isothermally at 39 degrees C and 15 degrees C and cells shifted from 39 degrees C to 15 degrees C. However, the acylating ratio of linoleoyl-CoA to palmitoyl-CoA, which were chosen as typical unsaturated and saturated fatty acyl-CoAs, in the microsomes from cells grown at 15 degrees C was 1.5-3.0-times higher than in the microsomes from 39 degrees C-grown cells in four acyltransferase activities. These results suggest that the changes of acyl-CoA specificities in reacylation enzyme activities during temperature down-shift would make little contribution to the increase in unsaturated fatty acids in phospholipids, although reacylating enzymes from isothermally grown cells at lower temperature would partially participate in those increases.

Acclimatization↗

Fibrinogen synthesis by megakaryocyte rich human marrow cell concentrates.

A rapid method is described for the production of a human marrow cell suspension highly enriched in megakaryocytes. These concentrates were incubated with radiolabelled amino-acids, and cell lysates were then analysed for fibrinogen synthesis. Neosynthesized proteins were detected by immunoprecipitation, immuno-affinity chromatography and electrophoresis. Fluorography of the electrophoresis gels showed three radioactive bands corresponding to the three chains of cold fibrinogen. Immunoblotting and autoradiography of bidimensional, nonreduced-reduced electrophoresis gels showed that these three proteins were joined by disulfide bonds in the cell. These results suggest that megakaryocytes synthesize fibrinogen, and imply that platelet fibrinogen is of megakaryocytic origin.

Autoradiography↗

Raynaud's phenomenon in chain saw users. Hot and cold finger systolic pressures and nailfold capillary findings.

To gain insight into the physiopathology of Raynaud's phenomenon of occupational origin, finger systolic pressures under heat and cold, and results of nailfold capillary microscopy, were examined in 29 lumberjacks with Raynaud's phenomenon vibration syndrome (pathological group) and 24 lumberjacks without it (non-pathological group), and compared with the same values in 26 healthy matched manual workers not using a vibrating tool (controls). Vibration syndrome physiopathology seemed multifactorial, combining 5 features: a rise in brachial diastolic and systolic pressures in the pathological group compared with the two other groups. In lumberjacks with Raynaud's phenomenon, these rises seemed to be acquired, since they were not found when the workers were engaged; a reduction in the number of nailfold capillaries (9.4 +/- 2 per mm in the pathological group vs 11 +/- 2.5 in the controls, P less than 0.025); a rise in the brachial digital systolic gradient (P less than 0.025) in the pathological versus the non-pathological lumberjack group abnormal cold vascular tone, since at 15 degrees C finger systolic pressures in the pathological group were lower than pressures in both the control and non-pathological groups (P less than 0.05 and P less than 0.01, respectively), and at 10 degrees C, they were lower in the pathological than in the control group (P less than 0.01); Within the pathological group, individual paired comparisons between the most and least symptomatic finger revealed a rise in the cold vascular tone, and a reduction in the number of nailfold capillaries in the most symptomatic finger compared to the least symptomatic finger.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗

Topographic expression of p21WAF1/SDI1/CIP1, bcl2, and p53 is altered at the early stage of colorectal carcinogenesis.

We analyzed the expression of p21, bcl2, and p53 in normal and different pathologic mucosa of the human colorectum using immunohistochemistry and cold polymerase chain reaction-single strand conformation polymorphism. The topography of normal mucosa showed; bcl2 and p53 expression restricted to basal epithelial cells and p21 expressed only in superficial epithelial cells. This topographic expression was altered in hyperplastic polyps and adenomas. Hyperplastic polyps revealed absence of or weak bcl2 expression and strong p21 expression without topography. In adenomas, whereas bcl2 expression increased and extended to parabasal and superficial dysplastic epithelium, the increase of p21 expression was limited to surface dysplastic epithelium. p53 was weakly expressed throughout the full thickness of dysplastic epithelium. Bcl2 expression in adenomas was stronger than in carcinomas; p53 expression was converse and p21 expression was variable. In carcinomas, this topographic expression was largely abrogated but p53 mutation (36%) was more frequent than in adenomas (2%). In carcinomas, p21 and p53 expression correlated inversely, but there was no relationship with bcl2. These results suggest that there is precisely ordered topographic pattern of p21, bcl2, and wild p53 expression in normal colorectal cells, but this becomes disordered during the early stage of colorectal carcinogenesis.

Colorectal Neoplasms↗

[Yersinia enterolitica infections: 2. Impact on human health].

The clinical picture of yersiniosis in humans and its prevalence in the human population is described in detail. Mass production of animals, development of meat factories based on sophisticated chains of cold storage units and international trade of meat products and animals are believed to be the reasons for the increasing prevalence of yersiniosis in humans. In Germany, anti-Yersinia antibodies are found in up to 40% of the average population. The financial losses for the national economy cannot be judged. Of special interest for industrial medicine are sequelae-like reactive arthritis in exposed occupational groups such as veterinarians or butchers. However, the lack of national and international data makes the assessment of the potential of yersiniosis as a zoonosis difficult. Therefore, intensive and interdisciplinary research is needed to close the gaps described. Already proven and proposed countermeasures at the different stages of mass production of animals and reglementations for international trade of meat products and animals are introduced. The need for development not only of cheap and rapid diagnostic tools but also for countermeasures and treatment strategies is discussed.

Animals↗

WHO immunization programme and hospital procedure in the Melut district, upper Nile region, south Sudan, in the year 1983 (report).

During the year 1983 the immunization programme according to the WHO-standard was finally started in the Melut region. The tables give details on the extension of tetanus immunization for neonatal tetanus, DPT (diphtheria, pertussis, tetanus) and also measles in the Melut hospital in 1983. For the first time, a functioning chain of cold storage units could be installed in this hospital. From March to November, 1983 details of mother-child care and ambulant patient care were also recorded.

Adult↗

[Neuromeningeal listeriosis in adults. Clinical aspects and contribution of cotrimoxazole in monotherapy].

A series of 28 patients suffering from neuromeningeal listeriosis is reported. This disease is consecutive to infection by Listeria monocytogenes--an ubiquitous and opportunistic Gram-positive bacillus--and has become a public health problem: its incidence is increasing and its prognosis is very severe despite the development of new bacteriological identification methods. Human beings are contaminated by food, which explains the frequent outbreaks of epidemics which are widely publicized, the infection being one of the consequences of the unprecedented development of the food industry and the cold food chain. The predominant clinical picture is one of non-specific meningoencephalitis. In about 50 percent of the cases the subjects infected are "immunodepressed" and/or more than 60 years' old. The diagnosis is difficult since the bacteriological identification is delayed (direct examination of the cerebrospinal fluid is rarely positive) and this fluid may be sterile (hence the value of blood cultures). A probability treatment therefore must be initiated before the diagnosis is confirmed if an unfavourable outcome is to be avoided. In Listeria monocytogenes infection cotrimoxazole administered alone seems to be a better antibacterial therapy than the reference ampicillin-aminoside combination.

Adolescent↗

Ferritin from the spleen of the Antarctic teleost Trematomus bernacchii is an M-type homopolymer.

Ferritin from the spleen of the Antarctic teleost Trematomus bernacchii is composed of a single subunit that contains both the ferroxidase center residues, typical of mammalian H chains, and the carboxylate residues forming the micelle nucleation site, typical of mammalian L chains. Comparison of the amino-acid sequence with those available from lower vertebrates indicates that T. bernacchii ferritin can be classified as an M-type homopolymer. Interestingly, the T. bernacchii ferritin chain shows 85.7% identity with a cold-inducible ferritin chain of the rainbow trout Salmo gairdneri. The structural and functional properties indicate that cold acclimation and functional adaptation to low temperatures are achieved without significant modification of the protein stability. In fact, the stability of T. bernacchii ferritin to denaturation induced by acid or temperature closely resembles that of mesophilic mammalian ferritins. Moreover iron is taken up efficiently and the activation energy of the reaction is 74.9 kJ.mol(-1), a value slightly lower than that measured for the human recombinant H ferritin (80.8 kJ.mol(-1)).

Amino Acid Sequence↗

Myosin light chain phosphorylation is correlated with cold-induced changes in platelet shape.

Chilling induces shape changes in platelets from disks to spheres with abundant filopodia. Such changes were time-dependent and correlated well with the phosphorylation of 20-kDa myosin light chain (LC20). Both the shape changes and the phosphorylation were reversible. After the platelets had been chilled, myosin became incorporated into the Triton X-insoluble fraction. When the chilled platelets were immunocytochemically stained, anti-myosin antibody was localized with filamentous structures inside the filopodia. These results suggest that LC20 phosphorylation and subsequent interactions with actin filaments play a crucial role in the cold-induced changes in platelet shape and in the formation of filopodia.

Blood Platelets↗