SEARCH · PubMed Health

Results for “Pasteurization”

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 127 records · Page 7Linked to original sources

PubMedDate not supplied

[Pathogenicity expressed by inhibition of the Pasteur effect].

The experiments carried out demonstrate that under the influence of tetanus exotoxin, Gram-negative bacteria endotoxins, staphylococcal infection and infestation with Tr. spiralis, inhibition of the Pasteur effect occurs. Recently published data show that the same manifestation of pathogenicity is induced by diphtheria alpha and delta exotoxin, staphylococcal toxin, Pseudomonas aeruginosa exotoxin, staphylococcal enterotoxin, streptolysin O, infections with Cl. perfringens, Pasteurella and Rickettsia and hepatitis viruses in man. These data confirm a previous hypothesis according to which inhibition of the Pasteur effect represents the expression and metabolic measure of pathogenicity and toxicity. The inhibitory effect was proportional to the amount of pathogenic agent or toxin, just as the respective anatoxin or toxin + endotoxin mixture does not influence the Pasteur effect. The metabolic criteria of the Pasteur effect, i.e. inhibition of hyperlactacidaemia and decrease of the organic P/inorganic P ratio, are thus the direct indices of pathogenicity and toxigenicity. This also accounts for deep alteration of the Pasteur effect in infections generating states of infectious and endotoxinic shock.

Animals↗

PubMedDate not supplied

Rapid impedance method for predicting the potential shelf life of packaged pasteurized milk.

The potential shelf life of packaged pasteurized milk was studied using a rapid impedance method. The results showed a high correlation between the shelf life of Fengxing and Xiang Man-lou pasteurized milks and between the detection time and the logarithm of colony-forming units per milliliter. The impedance detection time was measured after preliminary incubation at 30 degrees C for 6 h for 100 and 200 microL milk samples, or at 37 degrees C for 6 h for 100-400 microL milk samples for Fengxing pasteurized milk, and after 6 h preliminary incubation at 30 degrees C for 300 and 400 microL milk samples or 6 h at 37 degrees C for 100-400 microL milk samples for Xiang Man-lou pasteurized milk. Regressive equations were then constructed to predict the potential shelf life. Compared with the traditional method, the impedance method plus pre-incubation of milk at elevated temperatures (30 and 37 degrees C) was rapid, accurate, and convenient. The entire estimation process was completed within 11-14 and 14-20 h for Fengxing and Xiang Man-lou pasteurized milks, respectively.

Animals↗

PubMedDate not supplied

Histological findings in a human autogenous pasteurized bone graft.

BACKGROUND: Autogenous bone graft after pasteurization is one of the most valuable procedures for reconstruction of large bone defects following excision of malignant musculoskeletal tumors. To date, there have been no documented histological reports on pasteurized bone grafts, apart from short-term histological results. CASE REPORT: We treated a 27-year-old male with a periosteal chondrosarcoma of the tibia by wide excision and reimplantation of the large pasteurized bone. Biopsy specimens harvested from the pasteurized bone over 3 years after reimplantation were evaluated histologically. The graft cortices remained totally necrotic with empty osseous lacuna, whereas the architecture of the acellular cortical bones was still maintained without microfractures. Deposited seams of woven bone existed focally on the surface of the acellular trabeculae. CONCLUSION: Our medium-term histological outcome suggests the limitations of incorporating a pasteurized hone graft, but also advocates its role as a useful temporary material for the reconstruction of massive bone defects.

Adult↗

PubMed1989

Institut Pasteur v. United States: the AIDS patent dispute, the Contract Disputes Act and the international exchange of scientific data.

In the case of Institut Pasteur v. United States, the Institut Pasteur (Pasteur) claimed that the National Cancer Institute (NCI) had breached express and implied contracts to share research on AIDS virus samples provided to NCI by Pasteur. NCI scientists allegedly used the samples to acquire information which allowed NCI to file patent applications for an AIDS blood test kit. The United States Claims Court dismissed the complaint by holding that the Institut Pasteur had not complied with certain administrative procedures required by the Contract Disputes Act before bringing its suit. The United States Court of Appeals for the Federal Circuit reversed the decision of the Claims Court by holding that the disputed contracts did not fit within the scope of the Contract Disputes Act. Soon after the Court of Appeals decision, President Reagan and Prime Minister Chirac announced a settlement agreement whereby the lawsuit was to be dropped, American and French scientists were to share credit for having discovered the AIDS virus, and both parties to the suit were to share the patent rights for the AIDS blood test kit. This settlement suggest that international legal disputes involving urgent scientific and medical matters may require dispute resolution techniques that serve as alternatives to national courts.

Academies and Institutes↗

PubMed1977

[Coliform bacteria in raw and pasteurized milk].

Studied were 360 samples of raw and 1404 samples of pasteurized milk, collected from three milk centers, for the presence of coliform bacteria. It was found that the coli titer of the raw milk varied from 10(-5) up to 10(-7), depending on the season. The regimes of pasteurization applied kill 100 per cent of the present coli organisms. After the thermic treatment the milk was additionally contaminated with coli forms from the containers and the equipment in dependence on the conditions of washing and disinfection. The coli titer of the pasteurized milk varied from 1 to 10(-3). A total of 602 strains of coliform bacteria were isolated from the pasteurized and the raw milk; the bacteria were differentiated by the scheme of Kauffmann. Most commonly encountered were the coli forms of the following genera:Citrobacter (35 per cent), Enterobacter (29.8 per cent), Klebsiella (23.9 per cent), and Escherichia (11.3 per cent). The following species were prevailing in raw milk: Kl. aerogenes, Ent. aerogenes, Ent. cloacae, C. freundi, and C. intermedium. In pasteurized milk dominating were Kl. aerogenes, C. freundi. Ent. aerogenes, and Ent. cloacae.

Animals↗

PubMedDate not supplied

Pooled pasteurized breast milk and untreated own mother's milk in the feeding of very low birth weight babies: a randomized controlled trial.

It has been shown that milk derived from mothers with term infants is not optimal for premature babies. There is also concern about the effect of heat sterilizing breast milk. At Baragwanath Hospital, the majority of mothers remain with and care for their premature babies. Over many years, pooled pasteurized breast milk has been fed to these babies before direct breast feeding is instituted. A study was done to compare feeding pooled pasteurized breast milk and untreated own mother's milk to very low birth weight babies. There was a significantly more rapid weight gain both in terms of regaining birth weight and, from this point, to reaching a weight of 1,800 g when using untreated own mother's milk. This occurred in spite of the fact that there was little difference, especially in terms of energy content, between the two types of breast milk. This was due to the fact that the pooled pasteurized milk was also largely obtained from mothers of premature babies. It is suggested from our data that slower weight gain in the group receiving the pooled pasteurized milk could be due to the pasteurization, which probably destroys heat-labile milk lipase.

Body Weight↗

PubMed1980

[Mathematical model for carbohydrate energy metabolism. Mechanism of the Pasteur effect].

The simple mathematical model based on the stoichiometric structure of carbohydrate metabolism and the only allosteric regulation presented, i. e. activation of phosphofructokinase by AMP, was used to study the mechanism of the Pasteur effect, e. g. interrelationship of glycolysis, the Krebs cycle and H-transporting shuttles at varying rates of oxidative phosphorylation and ATPase load. It was shown that the mechanism of the Pasteur effect is based on the presence of two negative feed-back mechanisms in carbohydrate metabolism, namely by the level of ATP in glycolysis and by the level of mitochondrial NADH in the Krebs cycle and H-transporting shuttles. It was also shown that the value and sign of the Pasteur effect depend on the level of ATPase load. The role of this phenomenon in stabilization of ATP in the cell is discussed. The effects of changes in the allosteric properties of phosphofructokinase and low activity of H-transporting shuttles on the Pasteur effect was studied. It was shown that the low values of the pasteur effect in tumour tissues are mainly determined by an insufficient activity of oxidative phosphorylation.

Adenosine Triphosphatases↗

PubMed1984

A multistate outbreak of infections caused by Yersinia enterocolitica transmitted by pasteurized milk.

In June and July 1982, a large interstate outbreak of Yersinia enterocolitica infections caused by an unusual serotype occurred in Tennessee, Arkansas, and Mississippi. Eighty-six percent of cases had enteritis characterized by fever, abdominal pain, and diarrhea. In three separate case-control studies, drinking milk pasteurized by plant A was statistically associated with illness. In a survey of randomly chosen households, 8.3% of persons who recalled having drunk milk from plant A during the suspect period experienced a yersiniosislike illness. Inspection of the plant and cultures of the available raw and pasteurized milk did not reveal the source or mechanism of contamination or a breach in normal pasteurizing technique. Although outbreaks of enteric disease caused by pasteurized milk are rare in the United States, the ability of Y enterocolitica to grow in milk at refrigeration temperatures makes pasteurized milk a possible vehicle for virulent Y enterocolitica. The extent to which milk is responsible for sporadic cases of yersiniosis is unknown.

Adolescent↗

PubMed1995

[1995--the year of L. Pasteur].

1995 was proclaimed by UNESCO and by the Pasteur Institute in Paris as the year of L. Pasteur. 1995 is the 100th anniversary of his death. The author of the submitted paper describes the life and work of this genius and at the same time gives an account of the most important contributions of Pasteur's research activities for natural and medical sciences. Pasteur's work is developed further not only in Pasteur's Institute in Paris but also in other research centres worldwide, incl. the Czech and Slovak Republic.

France↗

PubMed1979

The Pasteur effect and catabolite repression in an oxidative yeast, Kluyveromyces lactis.

The presence of the Pasteur effect in Kluyveromyces lactis grown in glucose was shown by azide-stimulated glucose fermentation. Extracts from these cells contained ATP-sensitive phosphofructokinase activity. Cells grown on succinate oxidized glucose slowly at first without azide-stimulated rates of fermentation. Phosphofructokinase in these cells was ATP-insensitive. The activity of NAD+-isocitrate dehydrogenase in cell extracts did not require AMP activation. These results suggested the presence of a Pasteur effect in glucose-grown but not in succinate-grown K. lactis, mediated by (a) ATP inhibition of phosphofructokinase (b) possibly via feedback control of glucose transport, but not by AMP activation of isocitrate dehydrogenase. Azide inhibition of the Pasteur effect during growth of the cells did not lead to catabolite repression of respiratory activity. The results therefore suggest that the Pasteur effect does not inhibit the development of a Crabtree effect in oxidative yeasts.

Adenosine Triphosphate↗

PubMed1996

The Pasteur effect in facultative anaerobic metazoa.

The existence and the regulatory mechanisms of the Pasteur effect in facultative anaerobic metazoa are discussed. There are three reasons for the controversy surrounding this phenomenon. 1) The different definitions of the Pasteur effect, 2) the antagonistic effect of metabolic depression and its species specific response to hypoxia, as well as 3) the laboratory-specific differences in the experimental procedures for analyzing the Pasteur effect and its regulation. This review aims to clarify the confusion about the existence of the Pasteur effect in facultative anaerobic metazoa and to offer possible molecular mechanisms.

Adenosine Triphosphate↗

PubMed2003

Radiographic analysis of pasteurized autologous bone graft.

OBJECTIVE: Local malignant bone tumor excision followed by pasteurization and subsequent reimplantation is a unique technique for reconstruction after resection of primary bone sarcomas. The purpose of this investigation was to assess the normal and abnormal long-term radiographic findings of intercalary and osteo-chondral pasteurized bone graft/implant composite. DESIGN AND PATIENTS: The long-term radiographic findings of pasteurized bone grafts used in reconstruction after resection of bone and soft tissue sarcomas in relation to patients' clinical data were reviewed retrospectively. Thirty-one patients (18 females, 13 males; age range 7-77 years, mean 30 years) who underwent surgery between April 1990 and January 1997 at the authors' institute constituted the material of this study. They were followed up for at least 3 years or until the patient's death (mean 69 months). The International Society of Limb Salvage graft evaluation method that assesses the fusion, resorption, fracture, graft shortening, fixation, subluxation, joint narrowing and subchondral bone was used for evaluation of the radiographs. RESULTS AND CONCLUSIONS: Twenty-one patients (68%) showed complete incorporation of graft and eight patients (26%) had partial incorporation. The overall radiographic evaluation rate was 81%. Fracture (10%) and infection (16%) were the main complications. No local recurrence was detected. These results indicate that pasteurization of bone is a useful option for reconstruction after resection of malignant bone tumors.

Adult↗

PubMed2000

Pasteurized intercalary autogenous bone graft: radiographic and scintigraphic features.

OBJECTIVE: Pasteurized autogenous bone graft sterilized at a low temperature (60 degrees C) is one option for reconstruction after resection of bone and soft tissue tumors. The purpose of this investigation was to assess the normal and abnormal radiographic and scintigraphic findings of pasteurized intercalary autogenous bone graft after resection of bone and soft tissue sarcomas. DESIGN: This was a retrospective evaluation of the radiography and bone scintigraphy findings in patients after treatment of bone and soft tissue sarcomas using an intercalary pasteurized autogenous bone graft. PATIENTS: Among 10 consecutive patients, eight had intercalary grafts, and they constitute the subjects of this study. All available radiography and bone scintigraphy findings were reviewed for the healing process and the possibility of complications. RESULTS AND CONCLUSIONS: Healing and incorporation of the graft were observed in five patients during the follow-up, but the other three did not heal satisfactorily. Rapid incorporation of pasteurized autogenous bone graft can be demonstrated by means of radiography and bone scintigraphy.

Adolescent↗

PubMed2003

Reconstruction with autologous pasteurized whole knee joint II: application for osteosarcoma of the proximal tibia.

Reconstruction of the knee joint for osteosarcoma of the proximal tibia is a formidable challenge. Here we present two patients whose knees were reconstructed with autologous grafts of whole-knee joint treated by extracorporeal pasteurization. Incorporation at the junction between host and pasteurized bone was evident. On the other hand, direct reattachment of the patellar tendon to the pasteurized tibia was not successful in case 1. In case 2, in contrast, the patella was divided followed by successful reconstruction at the osseous site. Avoiding reattachment of pasteurized ligamentous structure is recommended. The operation protocol is not ideal but so far may be superior to other reconstruction procedures because there are many fundamental complications such as low long-term survival of a massive prosthesis and the lethal risk of transfection (e.g. human immunodeficiency virus); moreover, immunological responses of the allograft can be avoided.

Adolescent↗

PubMed2004

Reconstruction surgery for patients with musculoskeletal tumor, using a pasteurized autogenous bone graft.

BACKGROUND: The pasteurized autogenous bone graft (PABG) is a new method to reuse resected and diseased autogenous bones after heat treatment at a comparatively low temperature (60 degrees C-65 degrees C). METHODS: The subjects of this study were ten patients with musculoskeletal tumor who underwent surgery with a PABG in the 6 years between 1995 and 2000. RESULTS: The pasteurized bone developed into bone union in all patients, except for the elderly patients who required repeat surgery. There were no infected patients. The PABG was performed by three different types of reconstruction, a segmental method, an intercalary method, and a combination method with an artificial joint as a spacer. No local recurrence of tumor the pasteurized bone was observed from in any patient. CONCLUSION: The PABG appears to be a comparatively easy, safe, inexpensive, and effective reconstruction method for musculoskeletal tumors. The pasteurized autogenous bone graft (PABG) is a new method to reuse resected and diseased autogenous bones after heat treatment at a comparatively low temperature (60 degrees C-65 degrees C).

Adolescent↗

PubMed2006

Pasteurization is effective against multidrug-resistant bacteria.

BACKGROUND: The emergence and rapid spread of multidrug-resistant isolates causing nosocomial infections, particularly pandrug-resistant Acinetobacter baumannii, pandrug-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and extended-spectrum beta-lactamase-producing Enterobacteriaceae are of great concern worldwide. METHODS: This study investigated the efficacy of pasteurization against contamination of culture tubes and plastic bags by the above 4 important multidrug-resistant bacteria. A 5-mL bacterial suspension with approximately 10(5) and 10(9) cfu/mL of each organism was inoculated into 3 sets of plastic bags and culture tubes and subjected to pasteurization in a washer at 75 degrees C for 30 minutes. RESULTS: A nearly total eradication was found after pasteurization of these 4 drug-resistant pathogens. CONCLUSION: Pasteurization was highly effective against drug-resistant bacteria. Strict adherence to appropriate infection control management for respiratory circuits is important for reducing the spread of drug-resistant bacteria among ventilator-assisted patients.

Bacterial Infections↗

PubMed2002

Pasteurization of milk and the heat resistance of Mycobacterium avium subsp. paratuberculosis: a critical review of the data.

Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) causes Johne's disease in ruminants (including cattle, sheep and goats) and other animals, and may contribute to Crohn's disease in humans. This possibility, and the fact that M. paratuberculosis may be present in raw milk, make it important to ensure that the heat treatment specified for pasteurization of milk will give acceptable inactivation of this bacterium, with an adequate margin of safety. Published studies of the heat resistance of this bacterium in milk have given widely differing results. Possible reasons for these differences, and the technical problems involved in the work, are reviewed. It is concluded that there is a need (i) for the adoption of an agreed Performance Criterion for pasteurization of milk in relation to this bacterium, (ii) a need for definitive laboratory experiments to understand and determine the heat resistance of M. paratuberculosis, and (iii) a need for an assessment of whether the minimum heat treatments specified at present for pasteurization of milk (Process Criteria) will meet the Performance Criterion for M. paratuberculosis. Measures are also required to ensure that commercial processes deliver continually the specified heat treatment, and to ensure that post-pasteurization contamination is avoided.

Animals↗

PubMed1998

Predictive modelling of inactivation of Listeria spp. in bovine milk during high-temperature short-time pasteurization.

A linear model was derived to describe the thermal inactivation of Listeria innocua in bovine whole milk in a high-temperature short-time pilot scale pasteurizer. Integrated lethal effect, or pasteurization effect (PE), was obtained by converting times at different temperatures in the various sections of the pasteurizer to the equivalent time at the reference temperature (72 degrees C). PE was then related by a simple linear function to the log10 of the % viable counts with a power transformation of the PE values to improve the linear fit. R2 values for the five L. innocua trials varied from 0.728 to 0.974. Validation of this model with Listeria monocytogenes confirmed that L. monocytogenes was more heat sensitive. Inter-trial variation was incorporated into the model using the @RISK simulation software. Output from simulations confirmed that pasteurization at the IDF standard conditions of 72 degrees C for 15 sec can ensure at least an 11-log reduction of L. monocytogenes. The results showed that L. innocua may be used as a model microorganism to assess the thermal inactivation of L. monocytogenes, since its heat resistance is at least equal to or greater than that of the pathogenic species.

Animals↗