Occurrence of the angiotensin-converting enzyme inhibiting tripeptides Val-Pro-Pro and Ile-Pro-Pro in different cheese varieties of Swiss origin

The contents of the 2 antihypertensive peptides Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) were determined in 101 samples from 10 different Swiss cheese varieties using HPLC with subsequent triple mass spectrometry. In the category of extra hard and hard cheeses, the Protected Denomination of Origin cheeses Berner Alpkäse and Berner Hobelkäse, L'Etivaz à rebibes, Le Gruyère, Sbrinz, Emmentaler (organic and conventional) and in the category of semihard cheeses, the varieties Tilsiter, Appenzeller 1/4 fat and full fat, Tête de Moine, and Vacherin fribourgeois were screened in the study. The average concentration of the sum of VPP and IPP in the screened cheese varieties varied to a large extent, and substantial variations were obtained for individual samples within the cheese varieties. The lowest average concentration of the 2 tri-petides was found in L'Etivaz à rebibes (n = 3) at 19.1 mg/kg, whereas Appenzeller 1/4 fat (n = 4) contained the greatest concentration at 182.2 mg/kg. In individual samples, the total concentration of VPP and IPP varied between 1.6 and 424.5 mg/kg. With the exception of a 10-yr-old cheese, VPP was always present at greater concentrations than IPP. Milk pretreatment, cultures, scalding conditions, and ripening time were identified as the key factors influencing the concentration of these 2 naturally occurring bioactive peptides in cheese. The results of the present study show that various traditional cheese varieties contain, on average, similar concentrations of the 2 antihypertensive peptides to the recently developed fermented milk products with blood pressure-lowering property. This may serve as a basis for the development of a functional cheese with blood pressure-lowering property.

Destruction of spores on building decontamination residue in a commercial autoclave

The U.S. Environmental Protection Agency conducted an experiment to evaluate the effectiveness of a commercial autoclave for treating simulated building decontamination residue (BDR). The BDR was intended to simulate porous materials removed from a building deliberately contaminated with biological agents such as Bacillus anthracis (anthrax) in a terrorist attack. The purpose of the tests was to assess whether the standard operating procedure for a commercial autoclave provided sufficiently robust conditions to adequately destroy bacterial spores bound to the BDR. In this study we investigated the effects of several variables related to autoclaving BDR, including time, temperature, pressure, item type, moisture content, packing density, packing orientation, autoclave bag integrity, and autoclave process sequence. The test team created simulated BDR from wallboard, ceiling tiles, carpet, and upholstered furniture, and embedded in the BDR were Geobacillus stearothermophilus biological indicator (BI) strips containing 10(6) spores and thermocouples to obtain time and temperature profile data associated with each BI strip. The results indicated that a single standard autoclave cycle did not effectively decontaminate the BDR. Autoclave cycles consisting of 120 min at 31.5 lb/in2 and 275 degrees F and 75 min at 45 lb/in2 and 292 degrees F effectively decontaminated the BDR material. Two sequential standard autoclave cycles consisting of 40 min at 31.5 lb/in2 and 275 degrees F proved to be particularly effective, probably because the second cycle's evacuation step pulled the condensed water out of the pores of the materials, allowing better steam penetration. The results also indicated that the packing density and material type of the BDR in the autoclave could have a significant impact on the effectiveness of the decontamination process.

A thermal spin transition in [Co(bpy)3][LiCr(ox)3] (ox = C2O4(2-); bpy = 2,2'-bipyridine)

In the three-dimensional oxalate network structures [M(II)(bpy)3][M(I)-M(III)(ox)3] (ox= C2O4(2-); bpy = 2,2'-bipyridine) the negatively charged oxalate backbone provides perfect cavities for tris-bipyridyl complex cations. The size of the cavity can be adjusted by variation of the metal ions of the oxalate backbone. In [Co(bpy)3][NaCr(ox)3], the [Co(bpy)3]2 + complex is in its usual 4T1(t2g5e(g)2) high-spin ground state. Substituting Na+ by Li+ reduces the size of the cavity. The resulting chemical pressure destabilises the high-spin state of [Co(bpy)3]2+ to such an extent that the 2E(t2g6e(g)1) low-spin state becomes the actual ground state. As a result. [Co(bpy)3][LiCr(ox)3] becomes a spin-crossover system, as shown by temperature-dependent magnetic susceptibility measurements and single-crystal optical spectroscopy, as well as by an X-ray structure determination at 290 and 10 K.

Cheek and tongue pressures in the molar areas and the atmospheric pressure in the palatal vault in young adults

The pressures acting on the maxillary and mandibular posterior teeth from the tongue and cheeks were measured in 24 adults aged 22-29 years. In addition, the pressure in the palatal vault was recorded. The pressure at two maxillary (buccal and lingual) and two mandibular (buccal and lingual) measuring points, and in the palatal vault was recorded simultaneously. Repeated recordings of the pressures at rest, and during chewing and swallowing were made. The pressures at rest were of similar magnitude (about 2 g/cm2) at the buccal and lingual sides of the mandibular posterior teeth. The median resting pressure at the maxillary posterior teeth was 2.7 g/cm2 on the buccal side and 1.0 g/cm2 on the lingual side. The difference in the maxilla was significant, but not in the mandible. It was concluded that the equilibrium of tooth position is maintained by the pressure from the cheeks and the tongue. During chewing and swallowing the pressures on the lingual side of the teeth were greater than those on the buccal side. At rest about half of the subjects had a negative pressure at the palatal vault, but no correlations between the resting pressure at the palatal vault and the resting pressures on the teeth were found.

[Lactose in human nutrition]

The disaccharide lactose is naturally present as a component of foods in milk and dairy products. In the gastrointestinal tract, lactose is hydrolysed by the enzyme beta-galactosidase (lactase) into glucose and galactose. These components are absorbed. In most people lactase activity decreases at the age of approximately 2 years of age. After this lactose intake can cause symptoms of bloating, flatulence, abdominal pain and diarrhoea due to the lactose reaching the large intestine. This phenomenon is called lactose intolerance. It is generally recommended that these people abandon the consumption of milk and dairy products. However, most lactose-intolerant people are able to digest small amounts of milk (approximately 200 ml). They can also consume cheese without (hard and semi-hard cheese) or only low lactose content (only present in 10% of soft cheese). These products are a very important source of calcium.

[Lactose intolerance and consumption of milk and milk products]

The disaccharide lactose is present as a natural component of foods only in milk and dairy products. In the gastrointestinal tract, lactose is hydrolysed by the enzyme beta-galactosidase (lactase) into glucose and galactose. These components are absorbed. With the exception of the caucasian race, the lactase activity decreases in most people at an age of 4 to 6 years. Lactose intake can cause symptoms of bloating, flatulence, abdominal pain, and diarrhea due to the lactose reaching the large intestine. This phenomenon is called lactose intolerance. It is generally recommended to those persons that they refrain from the consumption of milk and dairy products. However, most lactose intolerant people are able to digest small amounts of milk. They can also consume cheese that contains no (hard and semi-hard) or only small amounts of lactose (present in only 10% of soft cheeses). These products are very important sources of calcium. Compared to milk, the lactose content of yogurt is usually lower by about one third. Studies during the last 10 years have shown that in spite of its lactose content yogurt is very well tolerated by lactose intolerant persons. This advantage is ascribed to the presence of living lactic acid bacteria in fermented dairy products which survive passage through the stomach and also to the lactase present in these products.

Radiolysis of DNA in the presence of a protein studied by HPL-gel chromatography

The influence of bovine serum albumin (BSA) on the radiolysis of double-stranded DNA was studied by measuring the loss of highly polymerized DNA with HPL-gel chromatography. The scavenger capacity of BSA for OH.-radicals kBSA [BSA] was kept constant. at 7.8 x 10(5) s-1, when DNA (0.1 mg/ml) was irradiated under different gas conditions (air, N2 and N2O), at pH 7 and 5 and with different ionic conditions. The resulting protein radicals react with DNA producing DNA protein crosslinks and DNA double-strand breaks. The yield and the kind of DNA damage depend on the nature of the protein radicals and their association with DNA. High phosphate concentration prevents the association of BSA with DNA and causes a reduction of the protection by BSA against double-strand break-age of DNA. Radiolysis in the presence of BSA in perchlorate solution leads to more strand breakage and less protein crosslinking than in phosphate solution because perchlorate is more chaotropic than phosphate. Changing the pH from 7 to 5 increases the protection by BSA against DNA strand breakage.

Radiolysis of DNA studied by HPL-gel chromatography

Radiolytic loss of highly polymerized calf thymus DNA was measured by HPL-gel chromatography. Irradiation of DNA in 10(-2) mol dm-3 sodium phosphate under N2 and air caused the same loss. Under N2O this loss was doubled showing that the reactions of OH radicals mainly lead to strand breakage. The stability of the double helix is decisive for the yield of double strand breaks. In this work the radiation-induced degradation was altered by different sodium phosphate concentration, by substituting phosphate for perchlorate and by changing the temperature in the radiolysis of DNA under air. A decrease of the strength of non-covalent bonds in DNA always leads to an increase of degradation of DNA. Radiosensitivity of DNA is higher at pH 7 than at pH 9 or 5.

[Livedo reticularis and multiple vascular occlusions in a patient with HLA-B27-negative spondyloarthrosis and antiphospholipid antibodies]

We report the case of a 74-year-old patient with HLA-B27 negative spondylarthropathy presenting with acute disseminated vascular occlusions. The presence of livedo reticularis prompted a search for antiphospholipid antibodies which were found to be markedly elevated. Histopathological examination revealed noninflammatory vascular obstruction. The clinical evolution was rapidly fatal in spite of corticosteroid treatment. Livedo reticularis can be an important diagnostic clue to various types of underlying disease. Increased levels of antiphospholipid antibodies have been associated with thrombosis and thromboembolism, especially in the context of autoimmune diseases such as systemic lupus erythematosus. This paper reports antiphospholipid antibody-associated noninflammatory vascular occlusions in a patient with HLA-B27 negative spondylarthropathy. The pathogenetic mechanism of antiphospholipid antibody-mediated vascular occlusions is not completely understood and optimal therapy remains to be defined.

Short-term effect of whole milk and milk fermented by Pseudomonas fluorescens on plasma lipids in adult boars

The short-term effects of whole milk and milk fermented by Pseudomonas fluorescens, of the amino acid composition of the diet and of feeding frequency on the level of plasma lipids, were investigated in six 1-year-old adult boars. The experimental diets contained equal amounts of protein, carbohydrates, fat and cholesterol. After an adaptation period of 5 d for each experimental treatment, blood was collected at regular intervals during 48 h and plasma levels of cholesterol, triacylglycerol, high-density-lipoprotein (HDL)-cholesterol and low-density-lipoprotein (LDL)-cholesterol were examined. All variables except HDL-cholesterol showed distinct diurnal fluctuations, which were substantially influenced by feeding frequency. Variations in the amino acid composition of the experimental diets, which were within a physiological range, had no effect on the level of plasma lipids. Plasma lipid levels were significantly lower when the animals received the diets containing milk instead of the diet without milk: cholesterol, triacylglycerol, and LDL-cholesterol were reduced by 5.6, 5.8 and 10% respectively (pondered means) while HDL-cholesterol remained unaffected. Fermentation of whole milk by P. fluorescens reduced the lipid-lowering effect. Our findings suggest that the intake of diets containing milk results in a lower plasma cholesterol and LDL-cholesterol level than the intake of diets with a similar nutrient content which do not contain milk.

[Determination of retinol and alpha-tocopherol in milk and milk products using high-pressure liquid chromatography after saponification in serum vials]

An improved procedure is described for the determination of retinol and alpha-tocopherol in milk and dairy products using high-pressure liquid chromatography (HPLC). Samples are saponified in sealed 10-ml serum vials in the absence of oxygen, cooled and neutralized by injecting glacial acetic acid into the system. Retinyl acetate and 5,7-dimethyltocol respectively are used as the internal standards. The solution is extracted with hexane and the organic phase is cleaned up on a sodium sulphate/aluminium oxide column. The solution is evaporated under vacuum and dissolved in ethanol for HPLC analysis. A short reversed-phase column packed with RP-18, using methanol as the eluent, allows fast separations of both the vitamins.

[Health aims of patients following myocardial infarct and heart surgery: are the goals realistic?]

134 patients (11 females and 123 males, mean age 52 years) taking part in our rehabilitation program after myocardial infarction or bypass surgery were asked to say what they were aiming for as far as exercise, smoking habits and body weight are concerned. Follow-up was carried out by a questionnaire 6 months later. 120 patients (90%) were prepared to engage in some exercise on a regular basis. 112 (86%) of the 130 patients surviving actually met the criteria at follow-up. On admission 15 patients were smokers and at discharge still 12; 9 of whom intended to stop smoking. This would have left a smoking fraction of 2%. At the key date, however, 19% were either still smokers or had become smokers again. Only 43 patients were able to lose as much weight as they intended. Yet during the follow-up period the average weight of all patients remained constant. In short, the aims of our coronary patients are pitched extraordinarily high. Regular exercise is achieved easily, but with regard to smoking habits and required loss of weight the intentions are obviously somewhat too optimistic.

[Vocational rehabilitation after an aortocornary bypass operation]

To elucidate the influence of coronary bypass surgery on vocational status we studied 238 male patients operated upon for stable angina (mean age 53.3 +/- 7.4 years). The postoperative follow-up was 3.7 +/- 0.7 years. 33 patients died or had to be excluded because they had retired. 113 (55%) of the remaining 205 patients participated in a formal rehabilitation program (group A), whereas 92 (45%) patients did not (group B). There was no significant difference between the two groups with regard to pre- or postoperative clinical and angiographic data, except a higher rate of preoperative unemployment and of patients unfit to work for more than 6 months before operation in group B. The overall preoperative employment rate was 48%, whereas 3.7 years after operation 62% of all the patients were working (p less than 0.005), a net gain of about 30%. Return to work was significantly influenced by the NYHA classification after operation, exercise capacity in the bicycle stress test, duration of preoperative unemployment, type of work and age at operation. In group A the postoperative employment rate was higher than in group B (72% vs. 51%), especially in patients who had not worked before operation (62% vs. 32%). It is concluded that after coronary artery bypass surgery a net gain in employment rate can be expected and a formal rehabilitation program may help the patients to resume work postoperatively. However, definite conclusions cannot be drawn because of the retrospective, nonrandomized design of the study.

Endoscopy as final arbiter in controlled clinical trials in peptic disorders

Endoscopy should not be the sole final arbiter in controlled clinical trials of peptic disorders. Data on the response of symptoms to treatment and the occurrence of side-effects may be not as 'hard' as endoscopically assessed 'healing' and 'relapse', but may be clinically more meaningful. Furthermore, in most recent trials, 'healing' and 'relapse' were poorly defined; important information on residual mucosal lesions after healing was often neglected.

Intracamerally applied prostacyclin raises the intraocular pressure in the rabbit

The effects of prostacyclin (PGI2) upon intraocular pressure and pupil size were examined in anaesthetized rabbits. Intracamerally applied PGI2 within the dosage range of 0.1 to 1.0/microgram led to an increase of the intraocular pressure (IOP) measured directly and continuously, and to a miosis. 6-oxo-PGF1 alpha, the product of hydrolysis of prostacyclin did not influence IOP or reaction of the pupil. Topical single doses of PGI2 of 4 to 80/micrograms on conjunctiva and cornea of the eye had no effect.

[Enzymatic and scintigraphic determined infarct size: significance for left ventricular function following infarct]

In a prospective study, the relationship between extent and location of myocardial infarction and the resulting left ventricular dysfunction was assessed and the question asked, how well these parameters may be assessed non-invasively a few weeks after the acute event. One hundred and fifty survivors of a first myocardial infarction were studied in the acute stage by serial ECG and CPK recordings and 5 weeks later by thallium201-(Tl)-scintigraphy and radionuclide angiocardiography. Myocardial damage was assessed enzymatically (maximal CPK; CPKmax) in the acute phase and scintigraphically in the subacute phase using a Tl-score considering extent (in percent of total myocardium in each projection) and severity (decrease in thallium-uptake) of scintigraphic infarct defects. There were significant correlations between Tl-score and max. CPK (r = .69) as well as between Tl-score and left ventricular ejection fraction (LVEF) (r = .65; p less than .001 each), but this correlation was better for subgroups with anterior vs. inferior infarctions (r = -.68 vs. r = -.59; p less than or equal to .001 for each). Furthermore, LVEF could be predicted based on the Tl-score: 88% of patients with values less than 7 had an LVEF of greater than 45%, whereas 77% of patients with a thallium-score of more than 12 had an LVEF less than 45%. Reproducibility of the Tl-score assessed in 30 patients over 3 months was excellent (r = .96) with low variability between the two analyses (+/- 1.5). Thus, after a first myocardial infarction, a direct relationship between enzymatically and scintigraphically, assessed infarct size and LVEF could be demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

[Xanthine oxidase in homogenized cow's milk and Oster's hypothesis: a review]

Oster has postulated that the enzyme xanthine oxidase in homogenized cow's milk is the cause of myocardial infarction and angina pectoris. This enzyme may be absorbed by ingestion, especially of the small particles of the fat globules, and then carried by lymph streams to the arterial vascular system, where it is deposited into the myocardium. Then it destroys the aldehydes liberated from the cell membrane-based plasmalogens. This results in the intimal damage to the cell membranes of the arterial intima and the myocardium and ultimately in the development of typical atherosclerotic lesions in the arteries. The presented review is a critical approach to this hypothesis. The following factors are discussed: - the influence of conditions prevailing in the intestine and the stomach on the activity of the xanthine oxidase in milk, - the possibility of this enzyme being absorbed in the intestine, - the formation of antibodies against absorbed xanthine oxidase and - the behaviour of xanthine oxidase administered intravenously. Compared with present knowledge, this theory gives little evidence only.

[Effect of 1,25-dihydroxycholecalciferol in renal osteopathy]

9 patients with advanced renal failure and renal osteodystrophy documented by iliac crest biopsy were treated with 1,25-dihydroxycholecalciferol (average dose 0.53 micrograms per day) for 6 months. Under 1,25-DHCC there was a statistically significant increase in serum calcium and decrease in serum alkaline phosphatase and immune parathyroid hormone. Histomorphometric evaluation of posttreatment bone biopsies showed reduction of osteoclastic resorption and endosteal fibrosis. Osteoid volume decreased in most cases. In 3 patients with predominant fibroosteoclasia, bone turnover practically normalized. Bone mineral content of the radius (photoabsorptiometry) did not change with treatment. Transient hypercalcemia occurred in 5 patients and was easily corrected by adjustment of 1,25-DHCC dosage.

[Harmlessness to human health of the mold cultures used in cheesemaking]

Mould cultures are used for the manufacture of soft and blue cheese. The report deals with the present stage of knowledge of the question of mycotoxin-producers in mould cultures used for cheesemaking. The PR-toxin was isolated repeatedly from Penicillium roqueforti strains which were incubated on special media, but also from P. roqueforti cultures used for cheese manufacture. However, cheese ripening conditions do not favor the production of this toxin. Other catabolites from P. roqueforti such als roquefortine and isofumigaclavine have been found in cheese, but there is not much known about their toxic effect. No cancerogenic mycotoxins have been discovered in these types of cheese, except alfatoxin M1, which might however originate from contaminated milk. It must be concluded that the occurrence of tumors after feeding of a pure P. camemberti var. candidum culture is due to the effect of mycotoxins. On the other hand, further animal experiments with various mould culture stains used for cheesemaking have not confirmed these findings. On the basis of the literature consulted it may be said that the use of mould cultures for cheesemaking does not involve any risk for human health, that means it is toxicologically harmless.