PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “REFRIGERATION”

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 19 recordsLinked to original sources
PubMed2002

PIV measurement and numerical analysis of a new refrigeration compartment of a refrigerator.

A new cooling duct system was developed in order to increase the refrigerator performance in terms of uniform temperature distribution particle image velocimetry (PIV) and the commercial software FLUENT was used to compare the performance of the conventional cooling system with the new cooling system. The new cooling system effectively cooled the door basket region, thus increasing the uniformity of the temperature distribution in the refrigeration compartment.

Equipment Design↗
PubMed1997

Temperature distribution and prevalence of Listeria spp. in domestic, retail and industrial refrigerators in Greece.

The present paper examined the presence of Listeria spp. in the environment of domestic, retail and industrial refrigerators. From 136 household refrigerators, 136 surface samples were taken from the walls or shelves, and 125 from cheese compartments. Only two refrigerators harboured L. monocytogenes. From 228 food store refrigerators, 335 samples were taken. Of these, 118 were in in contact with cheeses, 69 with sausages, 21 with cheese and sausages, 20 with miscellaneous products and 107 from refrigerator handles. Listeria spp. and L. monocytogenes were found in 3.1% and 1.7%, of the samples respectively. Listeria spp. was not detected in any of the nine dairy plant refrigerators examined. Listeria monocytogenes and L. innocua were found in 4.5 and 36.4%, respectively, of the 22 refrigerators inside meat processing plants, with only one of 22 refrigerators handles being positive for L. monocytogenes. Temperature distribution in the refrigerators was also investigated. Fifty five per cent of the 136 domestic and 32% of the 228 retail store refrigerators had temperatures of greater than or equal to 9 degrees C. The range of refrigeration temperatures of the industrial refrigerators was 0-2 degrees C for meat plants and 2-7 degrees C for dairy plants. No correlation of any kind could be established between the prevalence of Listeria spp. and the temperature of the various refrigerators due to the low number of positive samples.

Food Microbiology↗
PubMed2001

Refrigeration of donor cells in preparation for bovine somatic nuclear transfer.

In mammals, preparation of donor cells for somatic nuclear transfer is very important because the character of the donor cell directly affects the efficiency and outcome of transfer. The protocols used most commonly for donor preparation are (i) disaggregating cells from fresh tissue 1-2 h before micromanipulation or (ii) trypsinizing cultured cells temporarily, after special treatments for 3-8 days (for example, serum starvation). In this study, a new simple protocol was designed, whereby the donor cells (cumulus cells) used in bovine somatic nuclear transfer were refrigerated. In brief, cultured cells at 80-100% confluency were detached using trypsin, washed by centrifugation, aliquoted into different vials and refrigerated at 4 degrees C. The density of viable cells was decreased after day 1 of refrigeration; however, the rate of decrease tended to slow down with increasing duration of refrigeration. Cells refrigerated for 15 days were seeded at a density of 5 x 10(4) ml(-1) and reached 70% confluency after day 2 of culture. Most cells had the normal number of chromosomes (2n = 60). Cells chilled at 4 degrees C for different durations were removed from refrigeration and immediately subjected to micromanipulation. The in vitro development of reconstructed embryos (fusion rates, cleavage rates, morula and blastocyst rates) indicated that there were no significant differences among treatment groups regardless of the duration of refrigeration (0-2 weeks) of the donor cells. Reconstructed embryos were transferred into the uteri of recipient cows. No significant differences were observed in established early pregnancies between embryos derived from the non-refrigerated donor cells and those derived from refrigerated donor cells. This study indicates that refrigeration of donor cells for 1-2 weeks is a feasible protocol for preparing donor cells for bovine somatic nuclear transfer, and does not compromise development in vitro and early development in vivo.

Animals↗
PubMed2003

Refrigeration of rainbow trout gametes and embryos.

Prolonged access to early embryos composed of undifferentiated, totipotent blastomeres is desirable in situations when multiple collections of gametes are not possible. The objective of the present study is to examine whether the refrigeration of rainbow trout Oncorhynchus mykiss gametes and early embryos would be a suitable, reliable, and efficient tool for prolonging the availability of early developmental stages up to the advanced blastula stage. The study was conducted continuously during fall, winter, and spring spawning seasons. In all, more than 500 experimental variants were performed involving individual samples from 26 females and 33 males derived from three strains. These strains represented three possible circumstances. In optimal one, gametes from good quality donors were obtained soon after ovulation. In the two non-optimal sources, either donors were of poor genetic quality or gametes were collected from a distant location and transported as unfertilized gametes. A highly significant effect of variability of individual sample quality on efficiency of gamete and embryo refrigeration was revealed. The source of gametes significantly affected viability of refrigerated oocytes and embryos, but not spermatozoa. On average, oocytes from optimal source retained full fertilization viability for seven days of chilled storage, significantly longer than from non-optimal sources. Spermatozoa, regardless of storage method, retained full fertilization ability for the first week of storage. Refrigeration of embryos at 1.4+/-0.4 degrees C significantly slowed the development. Two- week-old embryos were still in blastula stage. Average survival rate of embryos refrigerated for 10 days and then transferred to regular incubation temperatures of 9-14 degrees C was 92% in optimal and 51 and 71% in non-optimal source variants. No effect of gamete and embryo refrigeration on the occurrence of developmental abnormalities was observed. Cumulative refrigeration of oocytes and embryos resulted in an average embryo survival rate of 71% in optimal source variants after 17 days of refrigeration (7 days oocytes+10 days embryos). The study shows that both gamete and embryo refrigeration can be successfully used as an efficient tool for prolonging availability of rainbow trout embryos in early developmental stages.

Animals↗
PubMed1984

Effects of overnight refrigeration on the microscopic evaluation of sputum.

Microscopic evaluation of sputum permits selection of specimens suitable for culture, assessment of likely pathogens, and the best interpretation of culture results. We prospectively evaluated 50 sputum specimens which were promptly submitted to our clinical laboratory; smears and cultures were performed both immediately and after 20 h of refrigeration. Specimens were grouped according to the numbers of squamous epithelial cells and neutrophils per low-power field present on coded Gram-stained smears. The numbers of bacteria in five oil immersion fields were used to characterize smears for predominant, mixed, or scanty forms. After refrigeration, only three specimens changed group from a definite loss of squamous epithelial cells, and only two changed group from a definite loss of neutrophils. Based on cellular composition, the majority of samples would have been processed identically both before and after refrigeration. In contrast, organism forms detected on smears and their relative quantities were dramatically altered after refrigeration. A predominant smear form was gained in 11 and lost in 8 refrigerated specimens. The frequent changes on smears observed overall resulted from both increases and decreases in numbers of bacteria and yeasts. The majority of sputum culture results were insignificantly affected by the refrigeration of specimens. We conclude that 20 h of refrigeration renders sputum useless for the microscopic evaluation of potential pathogens and the subsequent interpretation of culture results. However, overnight refrigeration does not affect the determination from smears of sputum suitability for culture based on cellular composition.

Bacteria↗
PubMed1986

Health effects among refrigeration repair workers exposed to fluorocarbons.

Refrigeration repair workers may be intermittently exposed to fluorocarbons and their thermal decomposition products. A case of peripheral neuropathy (distal axonopathy) in a commercial refrigeration repairman prompted an epidemiological investigation of the health of refrigeration repair workers. No additional cases of peripheral neuropathy were identified among the 27 refrigeration repair workers studied. A reference group of 14 non-refrigeration repair workers was also studied. No differences were noted between groups for the ulnar (motor and sensory), median (motor and sensory), peroneal, sural, or tibial nerve conduction velocities. Refrigeration repair workers reported palpitations and lightheadedness significantly more often than workers in the reference group. No clinical neurological or electroneurophysiological abnormalities were detected in eight refrigeration repair workers followed up for three years during continuous employment.

Adult↗
PubMed1989

Stability of famotidine in minibags refrigerated and/or frozen.

The stability of famotidine 200 micrograms/ml in dextrose 5% injection (D5W) and in NaCl 0.9% (NS) solution in polyvinyl chloride (PVC) minibags was studied when these solutions were stored refrigerated at 4 degrees C for 14 days, or frozen at -20 degrees C for 28 days and then refrigerated for 14 days. Famotidine concentration was determined in the refrigerated samples immediately after compounding (time 0) and also on days 2, 4, 8, and 14 by high-performance liquid chromatography (HPLC). Famotidine concentration was determined by HPLC in frozen samples at time 0 and days 7, 14, 21, 28, 35, and 42. Solutions were also observed for visual changes and pH was tested at these time intervals. Results of the HPLC famotidine analysis demonstrated 94-107 percent recovery of famotidine in D5W and NS at 14 days in refrigerated samples and 98-100 percent recovery of famotidine in minibags frozen for 28 days then refrigerated for 14 days. Analysis of variance showed no time effect on the concentration of famotidine in refrigerated samples (p = 0.741). Linear regression of the frozen minibag data indicated no time effect. Famotidine 200 micrograms/ml is stable in dextrose 5% injection and NaCl 0.9% injection when stored in PVC bags at 4 degrees C for 14 days, or when frozen for 28 days and then subsequently refrigerated for 14 days.

Drug Stability↗
PubMed1998

Does refrigeration of urine alter culture results in hospitalized patients with neurogenic bladders?

A prospective, blinded study of 40 hospitalized spinal cord injured (SCI) patients was conducted to evaluate the effects of refrigeration on urinalysis and culture results. Urine samples were divided, with one aliquot examined within 4 hours and the other after 24 hours of refrigeration. Comparisons using Wilcoxon Signed Rank analysis showed no significant difference between fresh and refrigerated samples in white blood cell (WBC) count (z = -0.353, p = 0.724), number of bacteria (z = -0.772, p = 0.440), leukocytes (z = -0.277, p = 0.782), or colony counts of E. fecalis, E. coli, Citrobacter, Pseudomonas, Streptococcus, Yeast, or Acinetobacter (z = -1.00, p = 0.317; z = 0.00, p = 1.0; z = 0.00, p = 1.0; z = 0.00, p = 1.0; z = -1.00, p = 0.317; z = 0.00, p = 1.0; z = 0.00, p = 1.0, respectively). A statistically significant difference between fresh and refrigerated samples was found with "mixed" organisms (z = -2.565, p = 0.010) and a difference approaching significance was found with Staph aureus (z = -1.841, p = 0.066), both with colony counts of less than 50 k. No changes in cultures or colony counts occurred following refrigeration that would have resulted in altered treatment regimens. This study indicates that refrigeration of urine samples for up to 24 hours in the hospital setting rarely causes changes in identified organism type and causes no clinically significant changes in urinalysis or urine culture results in SCI patients.

Colony Count, Microbial↗
PubMed2001

The effect of refrigeration on the osmolality and pH of nonpreserved artificial tears containing carboxymethylcellulose.

INTRODUCTION: Nonpreserved artificial tears (NPAT) are a recommended treatment for dry eye. The manufacturers' instructions state to discard the container after initial opening and use. Some clinicians advocate the use and storage of NPAT in a zip-lock bag in a refrigerator for up to 12 h. The purpose of this study was to evaluate whether refrigeration of opened NPAT over a 12-h period had any effect on the pH or osmolality. METHODS: Forty individual carboxymethylcellulose NPAT samples were used in this study. The initial osmolality and pH of each sample were measured with a vapor pressure osmometer and electronic pH meter. The samples were refrigerated (4 degrees C) in closed zip-lock plastic bags for 12 h. After storage, the pH and osmolality of the samples were measured. The data were statistically analyzed for significant differences using a paired t-test. RESULTS: The mean initial pH and osmolality before refrigeration were 6.46 pH units and 304.10 mmol/kg, respectively. After refrigeration, the mean pH was 6.44 units, and mean osmolality was 305.87 mmol/kg. Paired t-tests revealed a nonsignificant difference (p > 0.05) for both pH and osmolality. CONCLUSION: Refrigeration of opened carboxymethylcellulose NPAT stored in closed zip-lock plastic bags does not have a significant effect on the osmolality or pH of the solution. Storage of NPAT containing carboxymethylcellulose is an acceptable practice with regards to stability of pH and osmolality.

Carboxymethylcellulose Sodium↗
PubMedDate not supplied

Chondrocyte viability in refrigerated osteochondral allografts used for transplantation within the knee.

PURPOSE: To evaluate cell viability and matrix characteristics of refrigerated osteochondral allografts implanted up to 44 days after harvest. METHODS: Sixteen refrigerated allografts underwent histologic and ultrastructural examination and fluorescence excitation analysis prior to implantation. The average size of the graft implanted was 6.2 cm(2) (+/-3.4 cm(2)). Refrigerated allografts averaged 30 days (range, 17 to 44 days) from donor expiration to implantation. Nine specimens underwent cell viability testing. The percent viability of refrigerated allografts prior to implantation averaged 67%. RESULTS: No significant correlations were noted between histologic score, electron microscopy score, matrix staining percent (MSP) score, and viability. When time to implantation was assessed, an inverse correlation was noted with MSP score (r =.539) (P < 0.05), indicating less matrix staining in grafts refrigerated longer after harvest. CONCLUSION: The current data indicate that refrigerated osteochondral allografts can be maintained for up to 44 days with average chondrocyte viability of 67%.

Cartilage, Articular↗
PubMed2001

[Factors affecting the temperature of domestic refrigerators].

A survey was carried out in France in 1999 in order to know the air temperature in domestic refrigerators and the factors which may effect this temperature. Temperatures were recorded at three levels (top, middle and bottom of the refrigerator compartment). A questionnaire was filled to acquire the following information: characteristic of family (number of family members, age, profession, income...), characteristic of refrigerator (trade, type, age, temperature setting, refrigerating type...) and the use condition (room temperature, near by heat source, built in, door opening frequency...). The average temperature of the 119 surveyed refrigerators was 6.6 degrees C. Descriptive analysis and multi dimensional analysis of factors effecting refrigerator temperature were carried out. The classification tree and the segmentation confirm the influence of the use condition (frequency of door opening, temperature setting, near by heat source and built in). There is no direct effect of one factor but the combination of all of them.

Equipment Design↗
PubMed1979

Medications not to be refrigerated.

A survey of selected drug labelers was conducted to generate a list of drug products that should not be refrigerated. Letters asking for information on products adversely affected by refrigeration were mailed to 109 drug product labelers. A second letter was sent to nonresponders and to labelers providing incomplete information. Responses were received from 97 labelers, 43 of whom stated that none of their products would be harmed by refrigeration. Eleven labelers were unable to provide conclusive data or a list of specific drug products that refrigeration would harm. Lists of drug products not to be refrigerated were provided by 43 labelers, some including explanations of the adverse effects of refrigeration. Pharmacists may find the survey's data useful in their patient education activities.

Drug Labeling↗
PubMed1994

Clinical and laboratory comparison study of refrigerated and cryopreserved bone marrow for transplantation.

Refrigerated storage for short-term preservation of bone marrow is an alternative to cryopreservation where chemotherapeutic regimens include drugs with short in vivo half-lives. We performed a clinical and laboratory comparison of bone marrow stored at 4 degrees C for up to 9 days to bone marrow cryopreserved at -90 degrees C for autotransplantation. After adjusting for the confounding effects of disease type or sex, no clinically meaningful variation in post-transplant course between refrigerated storage and cryopreserved was found. Therefore, the data presented in this study suggest that the clinical recovery indices following transplantation between the two storage groups are essentially equivalent. One potential advantage to refrigerated storage, however, is that it may provide an opportunity for extended exposure to growth factors and/or purging agents in vitro prior to transplantation. To prepare for an in vitro analysis of this hypothesis, we concentrated the stem cell population and compared the nucleated cell recovery, viability and colony forming potential following refrigerated storage of whole bone marrow and buffy coat to cryopreserved bone marrow stored for the same interval. While the nucleated cell recovery for cryopreserved marrow was significantly greater than for refrigerated storage, the viability and colony forming potential of the refrigerated storage was superior or equivalent, independent of prior processing.

Adolescent↗