Quantitative chromogenic immunohistochemical image analysis in cellprofiler software.

Visual grading of chromogenically stained immunohistochemical (IHC) samples is subjective, time consuming, and predisposed to considerable inter- and intra-observer variations. The open-source digital analysis software, CellProfiler has been extensively used for fluorescently stained cells/tissues; however, chromogenic IHC staining is routinely used in both pathological and research diagnostics. The current investigation aimed to compare CellProfiler quantitative chromogenic IHC analyses against the gold standard manual counting. Oral mucosal biopsies from patients with chronic graft-versus-host disease were stained for CD4. Digitized images were manually counted and subjected to image analysis in CellProfiler. Inter-observer and inter-platform agreements were assessed by scatterplots with linear regression and Bland-Altman plots. Validation comparisons between the manual counters demonstrated strong intra-observer concordance (r2 = 0.979), particularly when cell numbers were less than 100. Scatterplots and Bland-Altman plots demonstrated strong agreement between the manual counters and CellProfiler, with the number of positively stained cells robustly correlating (r2 = 0.938). Furthermore, CellProfiler allowed the determination of multiple variables simultaneously, such as area stained and masking to remove any nonstained tissue and white gaps, which also demonstrated reliable agreement (r2 = >0.9). CellProfiler demonstrated versatility with the ability to assess large numbers of images and allowed additional parameters to be quantified. CellProfiler allowed rapid high processing capacity of chromogenically stained chronic inflammatory tissue that was reliable, accurate, and reproducible and highlights potential applications in research diagnostics.

Milk processing quality of suckled/milked goats: effects of milk accumulation interval and milking regime.

Milk with a high concentration of fat and casein is required for cheese production, and these components have a major impact for both quality and yield of the curd. Recent observations have shown that suckling can elevate milk fat concentration in goats and our aim was therefore to check the hypothesis that animal welfare and cheese-processing properties of goat milk could be optimised by appropriate management of suckled/milked goats. Twelve Swedish dairy goats were kept together with one kid each in 4 different mixed management-systems (milking combined with partial suckling) in a cross-over design. Two milk accumulation intervals were tested; Short = dams and kids were together for 16 h (T16) and Long = ; dams and kids were together for 8 h (T8 h). In addition, two milking regimes were used; Suckled Before Milking = S and Milked Before Suckling = M. Milk accumulation interval referred to how long dams and kids were separated. The milk yield available for processing (milk offtake), was weighed and analysed from each milking occasion and the suckled milk yield was estimated by a weigh-suckle-weigh method (WSW) in combination with observing the suckling behaviour during the free suckling periods. Milking managements, such as 'suckling before milking (S)', increased milk fat concentration compared to milking before suckling (M) and 'Short accumulation treatments (T16)' gave higher milk fat, casein concentration and individual curd yield (%) compared to the 'Long accumulation treatment (T8)'. The total individual curd yield (g) was the same despite treatment, but the animal welfare was most likely higher in T16 where dams and kids spent more time together.

Bovine chromosomal regions affecting rheological traits in rennet-induced skim milk gels.

Optimizing cheese yield and quality is of central importance to cheese manufacturing. The yield is associated with the time it takes before the gel has an optimal consistency for further processing, and it is well known that gel formation differs between individual milk samples. By identifying genomic regions affecting traits related to rennet-induced gelation, the aim of this study was to identify potential candidate genes affecting these traits. Hence, rennet-induced gelation, including rennet coagulation time, gel strength, and yield stress, was measured in skim milk samples collected from 379 animals of the Swedish Red breed using low-amplitude oscillation measurements. All animals had genotypes for almost 621,000 segregating single nucleotide polymorphisms (SNP), identified using the Bovine HD SNPChip (Illumina Inc., San Diego, CA). The genome was scanned for associations, haplotypes based on SNP sets comprising highly associated SNP were inferred, and the effects of the 2 most common haplotypes within each region were analyzed using mixed models. Even though the number of animals was relatively small, a total of 21 regions were identified, with 4 regions showing association with more than one trait. A major quantitative trait locus for all traits was identified around the casein cluster explaining between 9.3 to 15.2% of the phenotypic variation of the different traits. In addition, 3 other possible candidate genes were identified; that is, UDP-N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyl-transferase 1 (GALNT1), playing a role in O-glycosylation of κ-casein, and 2 cathepsins, CTSZ and CTSC, possibly involved in proteolysis of milk proteins. We have shown that other genes than the casein genes themselves may be involved in the regulation of gelation traits. However, additional analysis is needed to confirm these results. To our knowledge, this is the first study identifying quantitative trait loci affecting rennet-induced gelation of skim milk through a high-density genome-wide association study.

Genetic parameters for rennet- and acid-induced coagulation properties in milk from Swedish Red dairy cows.

Milk coagulation is an important processing trait, being the basis for production of both cheese and fermented products. There is interest in including technological properties of these products in the breeding goal for dairy cattle. The aim of the present study was therefore to estimate genetic parameters for milk coagulation properties, including both rennet- and acid-induced coagulation, in Swedish Red dairy cattle using genomic relationships. Morning milk samples and blood samples were collected from 395 Swedish Red cows that were selected to be as genetically unrelated as possible. Using a rheometer, milk samples were analyzed for rennet- and acid-induced coagulation properties, including gel strength (G'), coagulation time, and yield stress (YS). In addition to the technological traits, milk composition was analyzed. A binary trait was created to reflect that milk samples that had not coagulated 40min after rennet addition were considered noncoagulating milk. The cows were genotyped by using the Illumina BovineHD BeadChip (Illumina Inc., San Diego, CA). Almost 600,000 markers remained after quality control and were used to construct a matrix of genomic relationships among the cows. Multivariate models including fixed effects of herd, lactation stage, and parity were fitted using the ASReml software to obtain estimates of heritabilities and genetic and phenotypic correlations. Heritability estimates (h(2)) for G' and YS in rennet and acid gels were found to be high (h(2)=0.38-0.62) and the genetic correlations between rennet-induced and acid-induced coagulation properties were weak but favorable, with the exception of YSrennet with G'acid and YSacid, both of which were strong. The high heritability (h(2)=0.45) for milk coagulating ability expressed as a binary trait suggests that noncoagulation could be eliminated through breeding. Additionally, the results indicated that the current breeding objective could increase the frequency of noncoagulating milk and lead to deterioration of acid-induced coagulation through unfavorable genetic associations with protein content (0.38) and milk yield (-0.61 to -0.71), respectively. The outcome of this study suggests that by including more detailed compositional traits genetically associated with milk coagulation or by including milk coagulation properties directly within the breeding goal, it appears possible to breed cows that produce milk better suited for production of cheese and fermented products.

Effects of breed and casein genetic variants on protein profile in milk from Swedish Red, Danish Holstein, and Danish Jersey cows.

In selecting cows for higher milk yields and milk quality, it is important to understand how these traits are affected by the bovine genome. The major milk proteins exhibit genetic polymorphism and these genetic variants can serve as markers for milk composition, milk production traits, and technological properties of milk. The aim of this study was to investigate the relationships between casein (CN) genetic variants and detailed protein composition in Swedish and Danish dairy milk. Milk and DNA samples were collected from approximately 400 individual cows each of 3 Scandinavian dairy breeds: Swedish Red (SR), Danish Holstein (DH), and Danish Jersey (DJ). The protein profile with relative concentrations of α-lactalbumin, ß-lactoglobulin, and α(S1)-, α(S2)-, κ-, and ß-CN was determined for each milk sample using capillary zone electrophoresis. The genetic variants of the α(S1)- (CSN1S1), ß- (CSN2), and κ-CN (CSN3) genes for each cow were determined using TaqMan SNP genotyping assays (Applied Biosystems, Foster City, CA). Univariate statistical models were used to evaluate the effects of composite genetic variants, α(S1)-ß-κ-CN, on the protein profile. The 3 studied Scandinavian breeds differed from each other regarding CN genotypes, with DH and SR having similar genotype frequencies, whereas the genotype frequencies in DJ differed from the other 2 breeds. The similarities in genotype frequencies of SR and DH and differences compared with DJ were also seen in milk production traits, gross milk composition, and protein profile. Frequencies of the most common composite α(S1)-ß-κ-CN genotype BB/A(2)A(2)/AA were 30% in DH and 15% in SR, and cows that had this genotype gave milk with lower relative concentrations of κ- and ß-CN and higher relative concentrations of αS-CN, than the majority of the other composite genotypes in SR and DH. The effect of composite genotypes on relative concentrations of the milk proteins was not as pronounced in DJ. The present work suggests that a higher frequency of BB/A(1)A(2)/AB, together with a decrease in BB/A(2)A(2)/AA, could have positive effects on DH and SR milk regarding, for example, the processing of cheese.

The occurrence of noncoagulating milk and the association of bovine milk coagulation properties with genetic variants of the caseins in 3 Scandinavian dairy breeds.

Substantial variation in milk coagulation properties has been observed among dairy cows. Consequently, raw milk from individual cows and breeds exhibits distinct coagulation capacities that potentially affect the technological properties and milk processing into cheese. This variation is largely influenced by protein composition, which is in turn affected by underlying genetic polymorphisms in the major milk proteins. In this study, we conducted a large screening on 3 major Scandinavian breeds to resolve the variation in milk coagulation traits and the frequency of milk with impaired coagulation properties (noncoagulation). In total, individual coagulation properties were measured on morning milk collected from 1,299 Danish Holstein (DH), Danish Jersey (DJ), and Swedish Red (SR) cows. The 3 breeds demonstrated notable interbreed differences in coagulation properties, with DJ cows exhibiting superior coagulation compared with the other 2 breeds. In addition, milk samples from 2% of DH and 16% of SR cows were classified as noncoagulating. Furthermore, the cows were genotyped for major genetic variants in the αS1- (CSN1S1), ß- (CSN2), and κ-casein (CSN3) genes, revealing distinct differences in variant frequencies among breeds. Allele I of CSN2, which had not formerly been screened in such a high number of cows in these Scandinavian breeds, showed a frequency around 7% in DH and DJ, but was not detected in SR. Genetic polymorphisms were significantly associated with curd firming rate and rennet coagulation time. Thus, CSN1S1 C, CSN2 B, and CSN3 B positively affected milk coagulation, whereas CSN2 A(2), in particular, had a negative effect. In addition to the influence of individual casein genes, the effects of CSN1S1-CSN2-CSN3 composite genotypes were also examined, and revealed strong associations in all breeds, which more or less reflected the single gene results. Overall, milk coagulation is under the influence of additive genetic variation. Optimal milk for future cheese production can be ensured by monitoring the frequency of unfavorable variants and thus preventing an increase in the number of cows producing milk with impaired coagulation. Selective breeding for variants associated with superior milk coagulation can potentially increase raw milk quality and cheese yield in all 3 Scandinavian breeds.

Evaluation of the stability of furosemide in tablet form during six-month storage in spaceflight and peculiarities of its pharmacokinetics and pharmacodynamics under conditions of anti-orthostatic hypokinesia.

OBJECTIVES: The present study investigated the stability of furosemide under space-flight conditions on board the International Space Station, as well as its pharmacokinetics and pharmacodynamics under conditions simulating exposure to some space-flight factors. METHODS: Quantitative analysis of furosemide tablets by HPLC was performed before spaceflight (background), then after six months storage under normal ground conditions (control) and under spaceflight conditions (SF). The pharmacokinetics and pharmacodynamics of furosemide were studied in six healthy volunteers after a single oral dose of 40 mg under normal conditions (background) and under anti-orthostatic hypokinesia (ANOH). RESULTS: Quantitative content of furosemide in tablets before SF was 40.19 ± 0.28 mg (100.47 ± 0.71%), after 6 months storage: under normal conditions (control) - 39.9 ± 0.39 mg (99.73 ± 0.98%), under SF - 39.24 ± 0.72 mg (98.11 ± 1.80%), which was within the prescribed limits. Studying basic hemodynamic parameters showed that in ANOH conditions 6 h after furosemide administration there was a statistically significant increase of the stroke volume (SV) (+36.5 Δ%), a tendency for increasing of the stroke index (SI) (+36.5 Δ%) and decreasing of the total peripheral resistance (TPR) (-21.9 Δ%) compared to baseline study. CONCLUSIONS: It has been established that various factors of space flight (overloading, excessive vibration, microgravity, etc.) do not negatively influence the stability of furosemide in tablet form during storage for 6 months on board the International Space Station.

Effect of storage and separation of milk at udder quarter level on milk composition, proteolysis, and coagulation properties in relation to somatic cell count.

Coagulation properties of milk are altered by elevated somatic cell count (SCC), partly due to increased proteolytic and lipolytic activity in the milk and, thereby, degradation of protein and fat during storage. Milk is commonly stored on the farm at cooling conditions for up to 2 d before transport to the dairy for processing. This study evaluated the effects of storage on milk with altered composition due to high SCC and the effects of exclusion of milk from individual udder quarters with high SCC on milk composition, proteolysis, and coagulation properties. Udder-quarter milk and cow-composite milk samples from 13 cows having at least 1 quarter with SCC above 100,000 cells/mL were collected on 1 occasion. In addition, commingled milk from only healthy quarters (<100,000 cells/mL) of each cow was collected, representing a cow sample where milk with elevated SCC was excluded. The milk samples were analyzed for total protein content; protein content in the whey fraction; casein, fat, and lactose contents; SCC; proteolysis; curd yield; coagulation time; and total bacterial count, on the day of sampling and after 2 and 5 d of storage at +4°C. In addition to SCC, duration of storage and total bacterial count had an effect on milk quality. The content of total protein, fat and protein contents in the whey fraction, and curd yield were found to have different storage characteristics depending on the level of SCC at udder-quarter level. The exclusion of milk from udder quarters with elevated SCC decreased the content of total protein and protein content in the whey fraction and increased the content of lactose at cow level. However, the effect of separating milk at udder-quarter level needs to be further studied at bulk tank level to evaluate the effect on overall total milk quality.

Day-to-day variation in milk yield and milk composition at the udder-quarter level.

Automatic in-line measurement of milk composition and milk yield could be a useful tool in management of the dairy herd. Data on milk components and milk yield provide information on milk quality alterations and cow health status but are also useful in planning feeding and breeding. In automatic milking systems, udder quarters are milked individually, enabling analysis and recording at the udder-quarter level. Frequent records of components require knowledge about day-to-day variations. A component with greater day-to-day variation needs more frequent sampling when used as a diagnostic tool and for management decisions. Earlier studies have described the day-to-day variations in milk components for cow composite milk, but with the quarter milking technique and the possible sampling at the udder-quarter level, knowledge about day-to-day variations at the udder-quarter level is needed. In this study, udder-quarter and cow composite milk samples were collected from 42 consecutive milkings of 10 cows during 21 d. Milk yield was recorded and the milk was analyzed for total protein, whey protein, casein, fat, lactose, and somatic cell count. The results showed that the day-to-day variations and mean values for 4 healthy udder quarters within a cow were similar. In addition, different milk components had different levels of day-to-day variation, the least variation being found in lactose (0.9%) and the greatest in fat (7.7%). This suggests that repeated milk sampling and analysis at the udder-quarter level can be used to detect alterations in composition and cow health and would, thus, be helpful in the management of the dairy herd.

Effects on blood pressure after treatment of obstructive sleep apnoea with a mandibular advancement appliance - a three-year follow-up.

Obstructive sleep apnoea (OSA) is a highly prevalent sleep disorder; it affects 4% of males and 2% of females. Hypertension has been shown to occur in 28-57% of OSA patients. There is a steady increase in evidence linking OSA to long-term cardiovascular morbidity including hypertension. The purpose of this study was to investigate whether mandibular advancement oral appliance (OA) treatment of OSA affects the patient's blood pressure (BP) in a 3-month and a 3-year perspective. Twenty-nine consecutive patients, with verified OSA defined as apnoea index (AI) >5 per hour and/or apnoea/hypopnoea index (AHI) > or =10 per hour, received an OA as treatment. BP was measured on three occasions; before treatment, after 3 months of treatment, and after 3 years of treatment. BP was measured with an electronic blood pressure monitor. The treatment effect of OA was measured after 3 months by repeated somnographic registration while the patient was wearing the OA. A treatment response was defined as AHI < 10; this was achieved in 25 of 29 patients (86%) at the 3-month evaluation. Significant reductions in blood pressure were attained between baseline and the 3-month evaluation (P < 0.001) and these changes remained at the 3-year follow-up in both systolic BP of -15.4 +/- 18.7 mm Hg and diastolic BP of -10.3 +/- 10.0 mm Hg. OA therapy reduced blood pressure in both a 3-month and a 3-year perspective in patients with OSA.

Effect of minor milk proteins in chymosin separated whey and casein fractions on cheese yield as determined by proteomics and multivariate data analysis.

The objective of this work was to find regressions between minor milk proteins or protein fragments in the casein or sweet whey fraction and cheese yield because the effect of major milk proteins was evaluated in a previous study. Proteomic methods involving 2-dimensional gel electrophoresis and mass spectrometry in combination with multivariate data analysis were used to study the effect of variations in milk protein composition in chymosin separated whey and casein fractions on cheese yield. By mass spectrometry, a range of proteins significant for the cheese yield was identified. Among others, a C-terminal fragment of beta-casein had a positive effect on the cheese yield expressed as grams of cheese per 100 g of milk, whereas several other minor fragments of beta-, alpha(s1)-, and alpha(s2)-casein had positive effects on the transfer of protein from milk to cheese. However, the individual effect of each identified protein was relatively low. Therefore, further studies of the relations between different proteins/peptides in the rennet casein or sweet whey fractions and cheese yield are needed for advanced understanding and prediction of cheese yield.

Effect of protein composition on the cheese-making properties of milk from individual dairy cows.

The objective of this study was to evaluate the effect of variations in milk protein composition on milk clotting properties and cheese yield. Milk was collected from 134 dairy cows of Swedish Red and White, Swedish Holstein, and Danish Holstein-Friesian breed at 3 sampling occasions. Concentrations of alphaS1-, beta-, and kappa-casein (CN), alpha-lactalbumin, and beta-lactoglobulin (LG) A and B were determined by reversed phase liquid chromatography. Cows of Swedish breeds were genotyped for genetic variants of beta- and kappa-CN. Model cheeses were produced from individual skimmed milk samples and the milk clotting properties were evaluated. More than 30% of the samples were poorly coagulating or noncoagulating, resulting in weak or no coagulum, respectively. Poorly and noncoagulating samples were associated with a low concentration of kappa-CN and a low proportion of kappa-CN in relation to total CN analyzed. Furthermore, the kappa-CN concentration was higher in milk from cows with the AB genotype than the AA genotype of kappa-CN. The concentrations of alphaS1-, beta-, and kappa-CN and of beta-LG B were found to be significant for the cheese yield, expressed as grams of cheese per one hundred grams of milk. The ratio of CN to total protein analyzed and the beta-LG B concentration positively affected cheese yield, expressed as grams of dry cheese solids per one hundred grams of milk protein, whereas beta-LG A had a negative effect. Cheese-making properties could be improved by selecting milk with high concentrations of alphaS1-, beta-, and kappa-CN, with high kappa-CN in relation to total CN and milk that contains beta-LG B.

Mass balance of trace elements in Walker branch watershed: relation to coal-fired steam plants.

A mass balance study of trace element flows at the TVA Allen Steam Plant at Memphis showed that most of the released Hg, some Se, and probably most Cl and Br are discharged to the atmosphere as gases. The elements As, Cd, Cu, Ga, Mo, Pb, Sb, Se, and Zn were concentrated in fly ash compared to slag and were more concentrated in the ash discharged through the stack than in that collected by the precipitator, while Al, Ba, Ca, Ce, Co, Eu, Fe, Hf, K, La, Mg, Mn, Rb, Sm, Sr, Ta, Th, and Ti showed little preferential partitioning between the slag and the collected or discharged fly ash. The elements Cr, Cs, Na, Ni, U, and V exhibited behavior intermediate between the latter two groups. This information about stack emissions of trace elements from the Allen Plant was used to estimate the likely range of air concentrations and input (dry and wet deposition) to the Walker Branch Watershed. The watershed, which is on the ERDA reservation at Oak Ridge, is within 20 km of three coal-fired steam plants, two in the TVA system and one belonging to ERDA. The estimated input values are compared to measurements of Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn in wet precipitation falling on the watershed during 1973 and 1974. Dry deposition of these elements could not be measured directly but estimates indicated that this could be of the same order of magnitude as the rainwater input. A six-month mass balance indicated that the watershed efficiently retains Pb (97-98% of the atmospheric input,) Cu (82-84%), while Cr (69%), Mn (57%), Zn (73%), and Hg (69%) are less well retained.

Immunohistochemical localization of lactoferrin in bovine exocrine glands.

The localization of lactoferrin (LF) was studied in bovine exocrine glands by the peroxidase-antiperoxidase method. In general, LF immunoreactivity was demonstrated in most of the serous demilunes of the mixed glands and in some but not all acinar cells of the serous glands. LF was not detected in the acinar cells of the mucous glands. LF immunoreactive cells were seen in the nasal and tracheal glands. The lacrimal and mammary glands were stained intensely, while the sweat glands were not stained. In the major and minor salivary glands, LF immunoreactivity was demonstrated in the serous demilunes and acini of the mixed glands and in some serous cells of the pure serous parotid gland. LF immunoreactivity was not seen in the gastrointestinal tract and pancreas, but the serous gland in the lamina propria of the bile duct was stained positively. In the male reproductive tracts, the prostate and bulbourethral glands were stained positively, but the vesicular gland was negative. In the female reproductive system, the uterine and Bartholin glands, the epithelial cells of the cervix and ampulla of the uterine tube reacted positively. However, the lesser vestibular gland did not react for LF. The present findings, that LF was demonstrated in the exocrine glands located mainly in the gateways of the digestive, respiratory and reproductive systems, may morphologically support the antibacterial role of LF.

Are aldehydes in heat-sterilized peritoneal dialysis fluids toxic in vitro?

OBJECTIVE: Chemical analysis of several brands of peritoneal dialysis fluids (PD fluids) has revealed the presence of 2-furaldehyde, 5-HMF (5-hydroxymethylfuraldehyde), acetaldehyde, formaldehyde, glyoxal, and methylglyoxal. The aim of this study was to investigate if the in vitro side effects caused by glucose degradation products, mainly formed during heat sterilization, are due to any of these recently identified aldehydes. DESIGN: Cell growth media or sterile filtered PD fluids were spiked with different concentrations of thealdehydes. MEASUREMENTS: In vitro side effects were determined as the inhibition of cell growth of cultured mouse fibroblasts or stimulated superoxide radical release from human peritoneal cells. RESULTS: Our results demonstrate that the occurrences of 2-furaldehyde, 5-HMF, acetaldehyde, formaldehyde, glyoxal, or methylglyoxal in heat-sterilized PD fluids are probably not the direct cause of in vitro side effects. In order to induce the same magnitude of cell growth inhibition as the heat-sterilized PD fluids, the concentrations of 2-furaldehyde, glyoxal, and 5-HMF had to be 50 to 350 times higher than those quantified in the PD fluids. The concentrations of acetaldehyde, formaldehyde, and methylglyoxal observed in the heat-sterilized PD fluids were closer to the cytotoxic concentrations although still 3 to 7 times lower. CONCLUSION: Since none of these aldehydes caused in vitro toxicity at the tested concentrations, the toxicity found in PD fluids is likely to be due to another glucose degradation product, not yet identified. However, it is possible that these aldehydes may still have adverse effects for patients on peritoneal dialysis.

Heat sterilization of fluids for peritoneal dialysis gives rise to aldehydes.

OBJECTIVE: To chemically identify and quantify glucose degradation products in heat sterilized fluids for peritoneal dialysis. DESIGN: Three different brands of commercial PD-fluids and one laboratory made fluid, sterilized either by heat or filtration, were investigated for the presence of aldehydes. MEASUREMENTS: Aldehydes were identified and quantified using high performance liquid chromatography and gas chromatography. RESULTS: The tested brands of heat sterilized PD-fluids were found to contain several different aldehydes while the sterile filtered PD-fluid contained none. The highest concentrations in commercial PD-fluids of these aldehydes were: acetaldehyde (420 microns), glyoxal (14 microns), methylglyoxal (12 microns) and formaldehyde (11 microns). Valeraldehyde was also identified but not quantified. The presence of 5-HMF (15 microns) and 2-furaldehyde (2 microns), which has been identified by others, was confirmed. CONCLUSIONS: The heat sterilization of commercial PD-fluids gives rise to several aldehydes which may contribute to adverse effects of PD-fluids on patients.

Emissions from unvented kerosene heaters.

Vapor-phase polynuclear aromatic hydrocarbon (PAH) emissions from unvented kerosene heaters were measured. During normal heater operations, tri- and tetra-cyclic PAHs were observed, whereas penta-, hexa- and hepta-cyclic PAHs were not observed. The convective-type heaters had significantly less PAH emissions than the radiant-type heaters. Emissions of particulate soot were also measured. The soot did not contain PAH. A two-compartment model is presented and used to simulate heater operation in a home. Certain simulated PAH levels are similar to that measured in the ambient air of large cities.

An immunohistochemical study on the development of progastricsin-immunoreactive cells in the bovine abomasal mucosa.

The development of progastricsin-immunoreactive cells in the abomasal mucosa of cattle fetuses was studied by immunohistochemistry. Progastricsin-immunoreactive cells were detected first in the fundic and pyloric regions of 52 cm in crown-rump length (CRL) fetuses (about 180 days of gestation). The frequency of occurrence of progastricsin-immunoreactive cells and the intensity of their immunoreactivity increased with the progress of gestation, but most of these immunoreactivities were restricted to the basal portion of the fundic and pyloric glands. After birth, in the fundic mucosa, progastricsin immunoreactivities were found not only in the chief cells but also in the surface mucous cells of the gastric pits. In the cow, the immunoreactivity of the surface mucous cells was even stronger than that of the chief cells. In the pyloric mucosa, progastricsin immunoreactivities were found in the gastric pits and in the basal portion of the pyloric glands, but they were organized in small groups and showed a patchy distribution in the basal portions.

Toxicity of effluent peritoneal dialysis fluid.

Commercial heat-sterilized fluids for peritoneal dialysis (PD) are unphysiological due to low pH, high osmolality, and the presence of several toxic glucose degradation products, formed during heat sterilization. These properties are all believed to negatively affect host defense in patients. Both the low pH and the high osmolality are known to equilibrate after being introduced into the abdominal cavity of patients. Cytotoxicity due to glucose degradation products has, however, not yet been studied in this respect. Effluent peritoneal dialysates were collected from patients after dwell times of 0, 5, 15, 30, 120, and 240 minutes. Cytotoxicity, measured as the inhibition of cell growth of a cultured fibroblast cell line (L929), osmolality, and pH were determined. PD fluids, due to the presence of degradation products, were found to remain cytotoxic after a dwell time of more than 30 minutes. However, after 4 hours no cytotoxicity could be observed in the effluent fluids. Osmolality slowly decreased during the entire dialysis period, while pH rapidly increased and was close to neutral within 5 minutes following instillation. It is concluded that the presence of glucose degradation in PD fluids may be as important as low pH and high osmolality for clinical complications.

Production of prochymosin, pepsinogen and progastricsin, and their cellular and intracellular localization in bovine abomasal mucosa.

A brief overview of research is presented on the production, cellular and intracellular localization of prochymosin, pepsinogen and progastricsin in bovine abomasal mucosa from fetus to adult. Prochymosin is produced early during gestation (10th week) and is significantly related to milk-feeding. Pepsinogen and progastricsin start to be produced later during gestation (20th week) and are produced in low amounts as long as the calf is fed milk. With age, pepsinogen becomes the dominating zymogen in the abomasal mucosa. Most of the cell types in the fundic gland have the ability to produce all three zymogens and are also found in the same individual secretory granules of these cells.