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PubMed1995

A method for determination of total glutathione and total cysteine as S-carboxymethyl derivatives by using an amino acid analyzer, and its application to samples from rat liver, kidney and blood after intraperitoneal administration of 2-(4-carboxy-D-gluco-tetrahydroxybutyl)thiazolidine-4-carboxylic acid.

The effects of intraperitoneal administration of 2-(4-carboxy-D-gluco-tetrahydroxybutyl)thiazolidine-4-carboxylic acid (CGUA), a cysteine derivative conjugated with glucuronic acid, on total glutathione and total cysteine contents in rat tissues were investigated. Total glutathione (GSH and GSSG) and total cysteine (cysteine and cystine) were determined by a new method consisting of preparation of S-carboxymethylglutathione (CMSG) and S-carboxymethylcysteine (CMC), respectively, and subsequent analyses with an amino acid analyzer. CGUA was determined by a coloration method employing an acidic ninhydrin reagent. Total cysteine contents in liver, kidney and plasma rapidly increased to 2.3, 2.7 and 6.5 times the levels of the controls, respectively, after CGUA administration at a dose of 5 mmol/kg of body weight. Total glutathione content did not change significantly in the liver or blood except for the kidney with a significant increase during the first 1-h period after administration. CGUA content increased markedly in these tissues, especially in the kidney, and 30% of administered CGUA was excreted in urine within 2h. These results indicate that CGUA is converted into cysteine in vivo, suggesting the usefulness of this compound for protection of the kidney and the liver.

Animals↗
PubMed1986

Taurine concentrations in fetal, neonatal and pregnant rats.

The concentrations of taurine in the fetal and neonatal organs, and the maternal organs, plasma and urine of rats between the 15th day of gestation and the 21st day after birth were determined using an automatic amino acid analyzer. In the fetal liver and brain and in the placenta, the taurine concentration was the highest of all ninhydrin positive compounds. In the fetal liver and placenta, the concentrations of taurine increased significantly with the gestational days. Concentrations of taurine in the brain were much higher in the fetus and neonate than that in the adult. Moreover, the total amount of taurine per fetus increased markedly after the 15th day of gestation, and near term, reached almost the same amount as in the adult rat liver. In contrast to this, a significant decrease was observed in the taurine concentration in the maternal liver and muscle near term. The concentration of taurine in the urine of pregnant rats decreased near term, but in the plasma of pregnant rats the concentration of taurine did not change during pregnancy.

Amino Acids↗
PubMed1978

The effect of intrasulcular toothbrushing on the amount of sulcular fluid.

Nineteen young adult Caucasian males had an average Gingival Score of 0.47. Each was asked to demonstrate his present method of toothbrushing. Thirteen used a scrub method, and six combined the scrub and roll methods. Sulcular fluid measurements were taken from the facial aspect of the mandibular left second bicuspid using filter paper strips stained with ninhydrin. An average value of 0.94 mm was obtained. Intrasulcular brushing was performed in the mandibular left posterior segment, for 30 seconds daily for 40 days. The brushing was done by the investigator on 28 days and by the subjects on 12 days. The average Gingival Index score following intrasulcular brushing was 0.26. Sulcular fluid measurements were again taken from the mandibular left second bicuspid. A decreased amount of sulcular fluid was found in six subjects, while nine exhibited an increase and four showed no change. An average sulcular fluid measurement of 0.87 mm resulted following the experimental brushing period. From these data, it can be concluded that, within the limitations of this study, intrasulcular brushing had no significant effect on the amount of gingival fluid.

Adolescent↗
PubMed1984

Relative error (variability) associated with an improved instrument for measuring gingival crevicular fluid.

This investigation was undertaken to compare the variability in a new Periotron model 6000 to the variability in the previous Periotron model 600 and to the variability of the ninhydrin area method (NAM) for measuring quantities of fluid collected on filter paper strips. A Hamilton microliter syringe was used to deliver normal human serum to filter paper strips. Strips receiving varying quantities were randomly and blindly assigned to Periotron models 6000 and 600 until 10 strips containing each of 0.15, 0.30, 0.45, 0.60, 0.75, 0.90 and 1.05 microliter had been read using model 6000 and 10 strips containing each of 0.15, 0.30 and 0.45 microliter had been read using model 600. All strips were subsequently read using the NAM. The entire procedure was repeated using distilled water containing 0.1% methyl green. Coefficients of variation (CV) were computed for all sets of data. In all cases the CVs for the Periotron 6000 were significantly smaller than those for the Periotron 600 or the NAM. Pooled estimates of CVs (0.15-0.45 microliter) for the Periotron models 6000 and 600 were 0.054 and 0.116, respectively, (P less than or equal to 0.005) with serum and 0.059 and 0.095, respectively, (P less than or equal to 0.05) with distilled water containing 0.1% methyl green. Pooled estimates of CVs (0.15-1.05 microliter) for the Periotron model 6000 and the same strips subsequently measured with the NAM were 0.046 and 0.069, respectively, (P less than or equal to 0.005) with serum and 0.055 and 0.076, respectively, (P less than or equal to 0.001) with distilled water containing 0.1% methyl green.(ABSTRACT TRUNCATED AT 250 WORDS)

Equipment Design↗
PubMedDate not supplied

An integrated chemical, thermal, and microbiological approach to compost stability evaluation.

The evaluation of compost stability is of the utmost importance for the reliability of composting as a recycling strategy. To date there is no single parameter that can give a sure indication of the stability of composts from different starting materials. This paper investigates different methods of evaluating the dynamics of transformation of materials and the stability level of the end products in a composting process. The following parameters were determined on compost samples of different ages from cotton (Gossypium herbaceum L.) cardings and yard wastes: humification index (HI), degree of humification (DH), thermogravimetry (TG) microbial biomass C (B(C)), and ninhydrin-reactive N (B(NIN)). Finally, from TG, derivative thermogravimetry (DTG) and differential scanning calorimetry (DSC) thermal stability parameters were deduced. Humification parameters in the end products (0.2 and 81% for HI and DH, respectively) showed the effective stability reached by the organic matter (OM). Thermal analysis evidenced the presence of two main organic pools with different thermal stability. During composting a relative increase in the more stable organic pool was indicated by the variation of the thermostability index R1 from 0.41 to 0.74. The parameter R1 was significantly correlated with both HI (r = -0.94; P < 0.05) and DH (r = 0.97; P < 0.05). Microbial biomass content dynamics reflected the availability of readily decomposable substrates. The ratio between B(NIN) and total N in the end product was 0.96%, indicating a good stability level. The simultaneous application of different approaches, considering different properties of composting materials, provides a more complete description of the stability and quality reached by the organic materials.

Biodegradation, Environmental↗
PubMed2006

Evaluation of extracted organic carbon and microbial biomass as stability parameters in ligno-cellulosic waste composts.

Extracted organic C and microbial biomass were evaluated as stability parameters in 3 different ligno-cellulosic waste composts. Organic C was extracted by both water and alkali and further separated in humic-like carbon (HLC) and nonhumic carbon (NHC). Conventional humification parameters, such as humification index and degree of humification were calculated from NHC and HLC. Microbial biomass carbon (B(C)) was determined as an indicator of the degree of biochemical transformation, whereas ninhydrin reactive N (B(NIN)) was measured to obtain the stability parameter B(NIN)/N(TOT) (N(TOT), total N). The water-extracted organic C did not provide reliable information on the transformations underwent by the ligno-cellulosic wastes during composting, since its content remained almost unaltered during the whole process. In contrast, parameters based on the alkali-extracted organic C and microbial biomass clearly reflected organic matter (OM) changes during the process. There was an increase in the net amount of HLC in the alkali extracts throughout composting, especially in the first 7 to 12 wk of the process, as well as a relative enrichment of HLC with respect to NHC. Values of humification index and degree of humification in end products were consistent with an adequate level of compost stability. The stability parameter B(NIN)/N(TOT) showed to be a reliable indicator of stability in ligno-cellulosic wastes. Parameters based on the alkali-extracted C and microbial biomass clearly reflected the transformation of the OM during composting and can be used as stability parameters in ligno-cellulosic waste composts.

Biodegradation, Environmental↗
PubMed1985

Amino acid patterns in human gastric juice in health and gastric disease.

The amino acids in human gastric juice were measured in the hospital control (n = 9), gastric ulcer (n = 10), duodenal ulcer (n = 12), gastroduodenal ulcer (n = 9), and gastric cancer patients (n = 16) by high performance liquid chromatography, and the total of 15 kinds of amino acids was correlated with value determined by Ninhydrin method. The patients with gastric cancer had elevated levels of all amino acids, especially alanine, leucine, valine and threonine. In all but the gastric cancer disease groups, the aromatic amino acids, phenylalanine and tyrosine as well as leucine were at high levels in 15 amino acids. The different patterns of amino acids in these four groups tended to correlate with the variabilities of protein loss from the gastric wall.

Adolescent↗
PubMedDate not supplied

[Evaluation of sensitivity in the fasciocutaneous neurovascular medial plantar island flap in reconstruction of soft tissue defects in the calcaneal region].

The soft tissue cover in the calcaneal region represents one of the great problems in the reconstructive surgery. The distant skin, muscle and musculocutaneous flaps are subjected to ulcers even with the orthopedic shoes. The island fasciocutaneus mid sole neurocutaneous flap can be a good substitute for the soft tissue cover due to its anatomic structure. The flap has the required dimensions, sticks well to the bone and the movements and mobility of the patient is unrestricted. This paper analyses the sensitivity of the transposed flap and the sole distal to the secondary defect observed in 30 patients. The evaluation was made after tactile tests, two-point discrimination test, the warm-cold test, the electrostatus of medial plantar nerve (MPN), and the ninhydrin test. All the tests, including the electrostatus MPN, done after 3 weeks and 3 months after the surgery, showed successful recovery of sensitivity in the transposed medial plantar flap. The results monitored after three months showed that the speed of the neural conduction recovery was 70% of normal neural reaction speed of the MPN. The modified operative techniques provide safe dissection of the plantar nerve with minimal neuropraxia. The postoperative recovery of sensitivity was more rapid, and without loss of sensitivity on the sole.

Adult↗
PubMed1976

Osmotic adjustment in an estuarine population of Urosalpinx cinerea (Say, 1822) (Muricidae, Gastropoda).

Individuals from a subtidal, estuarine population of the common oyster drill, Urosalpinx cinerea (Say, 1822), were brought into the laboratory and tested for osmotic adjustment to changing salinity. Tissue variables monitored at seven experimental salinities ranging from 10 to 40% were tissue fluid osmolality, chloride, sodium, potassium, free amino acids (FAA), ninhydrin-positive substances (NPS) and water content. The results of this study demonstrate that the test animals did not exhibit anisosmotic regulation at any of the experimental salinities. However, the data do suggest a high degree of hyper-ionic regulation of potassium at all experimental salinities and a hyporegulation of sodium between the 25 and 40% salinities. Taurine, aspartic acid, alanine and glycine were the four FAA present in relatively consistent high amounts. These four amino acids comprised from 59.6 to 75.7% of the total FAA pools. It is postulated that the population does not maintain its euryhaline survival status through an osmoregulatory mechanism. Rather, the population has probably adapted physiologically to withstand dilution of its body fluids during spring conditions of low salinities.

Amino Acids↗
PubMed1980

Measurement of glycosylated amino acids and peptides from urine of diabetic patients using affinity chromatography.

An affinity chromatography system has been developed that retains glycosylated amino acids and peptides. Using this system, synthetic 14C-glycosylated lysine (reduced with NaB3H4) was completely separated from a mixture of reduced 14C-glycosylated lysine and unmodified 3H-lysine. Amino acid analysis of the retained peak from hydrolyzed human diabetic hemoglobin previously reduced with NaB3H4 revealed an equimolar mixture of glycosylated valine and glycosylated lysine, in agreement with previously published data obtained using other methodologies. These data demonstrate that in alkaline solution, the NaB3H4-reducible breakdown products of nonenzymatically glycosylated proteins are adsorbed to m-aminophenyl boronic acid immobilized on Bio-Gel P-6, while nonglycosylated amino acids are not. This affinity chromatography system should facilitate the rapid evaluation of nonenzymatic glycosylation in a large number of diabetic tissues. Levels of retained compounds in urine from diabetic and normal patients were determined by measuring ninhydrin-positive material. Amino acid analysis of NaB3H4-reduced hydrolysates of these peaks showed that glycosylated lysine was the major borohydride-reducible adduct present (67%--86%). Linear regression analysis showed that the quantity of excreted compounds in normals correlated with body weight (r = 0.63). The mean level (mumol leucine-equivalent/24 h/kg body weight) in diabetics was over 1.5 times that found in urine from normal subjects (P < 0.005).

Carbon Radioisotopes↗
PubMed1989

Protease activity in pancreatic islet isolation by enzymatic digestion.

Commercial Collagenase* prepared from Clostridium histolyticum is widely used in isolation of pancreatic islets. It is known that the enzyme is very impure and that there are substantial variations in effectiveness between batches. Our studies suggest that one of the impurities of importance in islet isolation is a protease that has not been very well characterized. Comparison of two batches of enzyme, one of which was known to give good yields of islets and the other poor yields, showed that they had very similar activity against collagen (measured by digestion of insoluble collagen followed by assay of soluble products with ninhydrin) but substantially different activities against azocasein as measured by optical density increase (measured by release of dye). Eighteen batches of Collagenase were examined for efficiency in islet isolation, and the yields obtained correlated with manufacturer's data of activity against casein. The data show that low caseinase activity is associated with performance in islet isolation (r = .5 after adjusting for collagenase activity). The effect of supplementing a batch of collagenase, known to be poor in isolating islets, with proteolytic enzymes was investigated. Trypsin and papain had apparently no effect, but dispase significantly increased yield. Dispase alone failed to digest pancreas. Size-exclusion high-performance liquid chromatography identified a peak associated with high protease activity and efficiency in islet isolation, having an Mr of approximately 30,000, compared to 78,000 for collagenase. The protease, like collagenase, is inhibited by EDTA. Increased Ca2+ and Mg2+ (up to 10 mM) did not affect activity. Both the protease and collagenase are stable under normal use but are inactivated by heating at 56 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Effect of monensin and a protonophore on protein degradation, peptide accumulation, and deamination by mixed ruminal microorganisms in vitro.

Mixed ruminal bacteria (80 mg N/liter) degraded casein and soluble soy protein rapidly (.68 and .72 mg N/[liter.min], respectively), but ammonia was produced at a slower rate (.08 and .10 mg N/[liter.min], respectively). Because there was little increase in cell protein, ammonia production could not account for all the degraded protein. Large quantities of non-ammonia, non-protein nitrogen (NAN-NPN) accumulated, and this NAN-NPN reacted more strongly (2- to 14-fold) with ninhydrin after it was treated with 6 N HCl (110 degrees C, 24 h) or pronase E. Even after 96 h of incubation, 10% of the protein N was still found in the NAN-NPN pool. Monensin had little effect on protein degradation, but it caused a large decrease in ammonia production (P less than .05) and an increase in NAN-NPN (P less than .05). These results indicated that significant quantities of peptide N could not be degraded by ruminal microorganisms and that monensin could increase peptide flow from the rumen. Because 3,3',4',5-tetrachlorosalicylanide, a protonophore that inhibits both Gram-positive and Gram-negative bacteria, did not cause a greater decrease (P greater than .05) in ammonia than monensin, an ionophore that is primarily effective against Gram-positive bacteria, it seemed that the "protein sparing" of monensin could largely be explained by its inhibition of Gram-positive bacteria.

Ammonia↗
PubMed1980

Degradation of soluble and insoluble proteins by Bacteroides amylophilus protease and by rumen microorganisms.

Various soluble and insoluble proteins (6.25 mg) were incubated at 37 C with partially purified protease from Bacteroides amylophilus (156 micrograms) in 2.0 ml of .1 M potassium phosphate buffer, pH 7.6, for 2, 4, 6 and 18 hr, and the liberated amino acids were determined by the ninhydrin method. Results showed that (1) although soluble, serum albumin and ribonuclease A were resistant to hydrolysis; (2) soluble and insoluble proteins of soybean meal were hydrolyzed at almost identical rates; (3) soluble proteins from soybean meal, rapeseed meal and casein were hydrolyzed at different rates, and (4) treatment of resistant proteins (serum albumin, ribonuclease A and insoluble fish meal and rapeseed meal proteins) with mercaptoethanol in 8 M urea or oxidation with performic acid rendered these proteins susceptible to hydrolysis. It is concluded that (1) solubility or insolubility of a protein is not by itself an indication of the protein's resistance or susceptibility to hydrolysis by rumen bacterial protease; (2) structural characteristics of the properties which renders feed protein resistant to degradation is the presence of crosslinking disulfide bonds.

Animals↗
PubMed1981

Effect of monensin on breakdown of protein by ruminal microorganisms in vitro.

The effects of monensin on N metabolism by ruminal microorganisms in a semicontinuous culture system were determined. Rumen fluid inoculum was obtained from steers fed a hay-concentrate diet (60:40 ratio on a dry matter basis) containing 33 ppm monensin. Treatments were 0, 1 and 4 mg monensin/kg of incubation mixture, with starch, glucose, cellulose and casein used as the energy and protein sources. Casein degradation decreased linearly (P less than .01) with increasing levels of monensin, as did production of ammonia-N (P less than .05) and microbial N (P less than .01). Increases were observed in nonammonia, nonmicrobial N (P less than .01), alpha-amino N (P less than .10) an total peptides (P less than .001). The culture supernatant was fractionated on a Sephadex G-10 column to separate peptides. With the 4 mg/kg treatment, the percentage of the total ninhydrin positive material eluted at an elution volume:void volume ratio of 1.5 or less was greater than the percentage eluted with the 0 or 1 mg/kg treatments (P less than .025). Acetate production and molar proportion decreased (P less than .001), while propionate production was unchanged. Methane production decreased slightly (P less than .10). Cellulose degradation was markedly inhibited (P less than .001) by monensin treatment.

Ammonia↗
PubMed1986

Comparison of various amino acids for estimation of microbial nitrogen in digesta.

Methods of estimating microbial N in digesta were compared, and two simplified methods were described for separation of diaminopimelic acid (DAP) from methionine in acid hydrolysates of biological samples using an automated amino acid analyzer. Recoveries of DAP when added to bacterial, abomasal and feed samples were 92 to 98%. All samples analyzed (bacteria, protozoa and several feedstuffs) contained detectable DAP (or another amino acid with similar elution time). Apparent DAP-N (percentage of total sample N) in feeds ranged from 12 to 78% of bacterial DAP-N concentration. These values are greater than can be accounted for by bacterial contamination. Correction for apparent dietary DAP was appropriate when using this microbial marker. Reasonable estimation of bacterial N was made in abomasal digesta of steers fed high-grain diets using DAP, lysine or combinations of DAP and leucine or lysine and leucine. There was excellent agreement among these marker methods in ranking dietary treatment regimens with respect to bacterial N present in the abomasum. The use of leucine alone, or the combination of DAP and lysine, gave nonrealistic values. Two-amino-ethylphosphonic acid (AEP) was not detected in acid hydrolysates of mixed ruminal protozoa or abomasal digesta. Two other ninhydrin-reactive compounds with elution times close to AEP were detected in all samples analyzed, which may have been identified as AEP in other studies. It was concluded that corrected DAP and lysine were the best estimates of bacterial N and AEP was precluded as a marker of protozoal N.

Amino Acids↗
PubMed1976

The visibly fluorescent phospholipids of serum lipoproteins.

The blusih-white fluorescence exhibited by lipoproteins from human serum has been investigated. It appears that high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very low density lipoprotein (VLDL) all exhibit this fluorescence with excitation maximum at about 360 nm and fluorescence maximum at about 450 nm. The fluorescence resides in the phospholipid fraction of the lipoproteins and is not located in the fatty acids, since the water-soluble deacylated phospholipid fraction exhibited the same fluorescence. Upon electrophoresis of this fraction at pH 6.5 the fluorescent material carried a negative charge and moved a distance similar to glycerophosphoserine and glycerophosphoinositol, which both carry one negative charge. This negatively charged fluorescent product is ninhydrine negative, and gives a positive reaction for phosphate esters and 1,2-glycols. The detailed structure of the fluorescent product is not yet known. It is suggested that reactive aldehydes are involved in its formation from the aminophosphatides. Its possible relationship to tissue peroxidation is discussed.

Chromatography, Thin Layer↗
PubMed1988

Sustained delivery of difluoromethylornithine (DFMO) by means of implantable ceramic devices.

A total of 25 Sprague-Dawley albino male rats were assigned to five groups, each group consisting of five rats. Polylactic acid-impregnated ALCAP capsules filled with 40 mg DFMO were implanted subcutaneously (sc) or intraperitoneally (ip) in group I and II rats, respectively. Rats in group III were implanted with empty ALCAP capsules (ALCAP control). Group IV rats were administered orally 3% DFMO in drinking water. Rats in group V served as control. Blood samples were collected every week for six weeks via the tail artery. The concentration of DFMO was determined by a modified ninhydrin hydrindantin method. Data obtained in this investigation showed that the levels of DFMO in the serum of rats in groups I and II were 41.87 +/- 6.8 and 237.62 +/- 13.3 micrograms/mL, respectively. Body, spleen, liver, prostate, seminal vesicles, and testicular weights of the controls and DFMO treated rats were not significantly different (p less than 0.05) over the entire duration of this study. The diarrhea often noted in rats treated orally with DFMO was not observed in rats implanted with ALCAP capsules filled with DFMO. The results of this study suggest that (1) polymer-impregnated ALCAP ceramic capsules can be used to deliver DFMO in a sustained manner for long durations of time, (2) side effects associated with oral administration of DFMO can be avoided by using DFMO-filled ALCAP ceramic implants, and (3) a ceramic system can be designed to deliver DFMO and drugs such as DFMO in a sustained manner over long periods of time in humans.

Animals↗
PubMed1979

The neurovascular island pedicle flap.

Nine patients with irreparable damage to the nerves of the thumb, treated with a neurovascular island pedicle flap from the third or fourth finger to the defect thumb, have been re-examined 9 months to 8 years after the operation. Eight patients had a 2-point discrimination of less than 15 mm corresponding to the flap and all had a positive Ninhydrin test. Two had complete cortical reorientation and three partial reorientation. Six found the function of the thumb to be good or fair. Three described the result as poor and three had to be reoperated because of contractures of the donor finger and/or thumb. The method can be recommended for use in young, well motivated patients.

Adolescent↗