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At least 19 recordsLinked to original sources
PubMed1992

[A study on reaction mechanism of sodium lauryl sulfate-hemoglobin (SLS-Hb), Part 1].

The cyanmethemoglobin (HiCN) method has been adopted as the international standard procedure for hemoglobin (Hb) determinations due to the accuracy and stability of result. However, the presence of potassium cyanide (KCN) and potassium ferricyanide (K3-Fe(CN)6) in the reagents has raised problems of laboratory and environmental pollution. In 1981, Oshiro and colleagues developed a cyanide free method of Hb determination that is based on a low toxicity compound Sodium Lauryl Sulfate (SLS). The SLS-Hb method provides stable SLS-Hb formation through the following steps. 1) Reaction of SLS to erythrocytic membrane (disruption of the erythrocytic membrane). 2) Conformation change of Hb by SLS. 3) Iron oxidation by oxygen (Fe2+----Fe2+). 4) Formation of stable SLS-Hb (coordination of SLS). The paper presents several findings on the reaction mechanism of the SLS-Hb method.

Blood Cell Count↗
PubMedDate not supplied

[SLS--a new type of polynucleotide chain folding].

Short tandem repeats (5-8 base pairs) are not uncommon in the prokaryotic and eukaryotic DNA. Regions with such sequence motifs, when under superhelical stress, manifest unusual sensitivity to single-strand specific nuclease. To explain this, it has been suggested that one DNA thread should be shifted relatively to another, so that they could form two single-stranded loops protruding from the opposite chains and separated on the DNA helix by the length of a direct repeat. The structure was proposed to play a role in the regulation of transcription, organization of chromatin and in the recombination. Such type of folding could have been extra-stabilized by base pairing between the loops. This attractive possibility of the interloop minihelix formation requires a delicate stereochemical analysis and direct experimental support. Formation of the interloop minihelix in the Slipped Loop Structure (SLS) was tested by a chemical modification method at one nucleotide level resolution. The results show that bases located within the proposed interloop helix are well protected from the probes used. This fact encourages us to publish a 3-D model for the SLS-form DNA (and RNA). The SLS is characterized by a remarkable symmetry having three mutually perpendicular dyad axes. Scanning the bank of nucleotide sequences has revealed more than 500 sites, the transcripts of which are capable of folding into the SLS form, which allow us to regard the SLS form as a novel universal structural form. Remarkably, the abundance of SLS in intrones three times exceeds that of the coding sequences. This may reflect a functional role (or roles) of the SLS conformation.

Animals↗
PubMed1989

Post-application occlusion substantially increases the irritant response of the skin to repeated short-term sodium lauryl sulfate (SLS) exposure.

Occlusion often, but not always, enhances percutaneous absorption and thus may facilitate skin irritation. Quantitative data about the impact occlusivity may have on minimal irritant stimuli to which the skin is exposed in daily life, and which may lead to chronic irritant contact dermatitis, are however lacking. Irritant stimuli were administered by repeated application of sodium lauryl sulfate (SLS) in an open application procedure. After the open exposure, the skin was either left open or occluded with plastic. Skin irritancy was assessed by means of visual grading and by transepidermal water loss (TEWL) measurements. Post-exposure occlusive treatment markedly enhanced the irritant response. 5 consecutive daily applications produced more irritation, with or without occlusion, than alternate day application. Occlusion may be a relevant factor in the development of irritant contact dermatitis from certain chemicals.

Administration, Cutaneous↗
PubMed1992

Calcium antagonists in sodium lactobionate sucrose solution for rat liver preservation.

The effects of the calcium antagonists, chlorpromazine (CPZ), nisoldipine (NIS), trifluoperazine (TFP), and nicardipine (NIC) were compared in rat livers following either 20- or 30-hr ice storage in sodium lactobionate sucrose solution (SLS). Survivals beyond 7 days after orthotopic liver transplantation following 20-hr cold storage were 1/14 in the University of Wisconsin solution, 4/14 in SLS, 4/8 in UW+CPZ, 7/8 in SLS+CPZ. Survivals beyond 7 days after OLT following 30-hr cold storage were 3/8 in SLS+CPZ, 3/8 in SLS+NIS, 2/8 in SLS+TFP, 0/8 in SLS+NIC, and 0/8 in SLS alone. Survival rates were significantly (P less than 0.05) better in both SLS+CPZ and SLS+NIS than in UW and SLS alone. The effluent lactate dehydrogenase (LDH) levels and pH changes were measured at the time of OLT. After 20 hr, LDH levels were 525 +/- 78 IU/L (mean +/- SEM) in UW, 492 +/- 44 in SLS, 322 +/- 35 in UW+CPZ, and 290 +/- 39 in SLS+CPZ. After 30 hr, LDH values were 416 +/- 40 in SLS+CPZ, 450 +/- 25 in SLS+NIS, 448 +/- 21 in SLS+TFP, 573 +/- 18 in SLS+NIC, and 614 +/- 68 in SLS. The LDH levels for SLS+CPZ and SLS+NIS were significantly lower than those of SLS and UW (P less than 0.01). The pH changes in the effluent were significantly less in both the CPZ and NIS groups (P less than 0.01). This study demonstrated improved liver preservation by the use of a simplified colloid-free lactobionate solution containing sodium as the principal cation. The addition of CPZ or NIS to the solution demonstrated the same potency for significant improvement in efficacy of this solution, while NIC was ineffective.

Adenosine↗
PubMed1991

Biophysical alteration of lung surfactant by extracts of cotton dust.

Byssinosis, a lung disease that can affect cotton mill workers, may be caused in part by lipopolysaccharides (LPS) from Gram negative bacteria. In vitro, LPS complexes with sheep lung surfactant (SLS). To determine whether LPS in extracts of cotton dust alters the biophysical characteristics of lung surfactant, aqueous extracts (1.0% w:v) of sterile surgical cotton (SSC) and a bulk raw cotton dust (1182DB) were prepared. Aliquots of the soluble extracts were incubated with SLS and studied by sucrose gradient centrifugation, surface tension analysis, and high pressure liquid chromatography (HPLC). The chromatography was employed to analyse for 3-hydroxymyristate (3-HM), a fatty acid indicating LPS. Also, purified Enterobacter agglomerans LPS and 3-HM as controls and as mixtures with SLS, were studied by HPLC. Sucrose gradient centrifugation showed that SLS-SSC, SLS-1182DB, and the SLS control had similar densities that differed from the remaining controls. The SLS-1182DB exhibited a floccule absent in the other samples. Surface tension values of SLS-SSC and SLS-1182DB differed significantly from all controls but only slightly from one another. 3-Hydroxymyristate was detected by HPLC in the 3-HM control, EA-LPS, SLS-EA-LPS, and SLS-1182DB, but not in SLS-SSC or the remaining controls. Apparently, 3-HM was below the HPLC detection range in SSC. The data indicate that LPS in the 1182DB, SSC and EA-LPS samples complexed with SLS. Floccule development in SLS-1182DB but not in SLS-EA-LPS suggests a further component(s) present in the bulk raw cotton dust, as well as LPS, which complexes with SLS. The data suggest that biophysical alterations to lung surfactant may play a part in the pathogenesis of byssinosis.

Animals↗
PubMed1991

Successful 20-hour rat liver preservation with chlorpromazine in sodium lactobionate sucrose solution.

We investigated the effect of the addition of chlorpromazine to a new, simplified organ preservation solution, sodium lactobionate sucrose (SLS), for 20-hour hypothermic rat liver preservation. Survival beyond 7 days after orthotopic transplantation of the stored liver was eight of eight rats in control groups (immediate transplantation, less than 1-hour preservation), one of 14 rats with the University of Wisconsin (UW) solution, four of 14 rats with SLS, seven of eight rats with SLS + chlorpromazine, 1 mg/L, and seven of eight rats with SLS + chlorpromazine, 10 mg/L. The differences is survival between UW and SLS and between SLS and SLS + chlorpromazine were significant (p less than 0.05). Lactic dehydrogenase levels in the effluent after reflushing through the portal vein at the time of transplantation were 145 +/- 20 IU/L (mean +/- SEM) in the controls, 525 +/- 78 IU/L in UW, 492 +/- 44 IU/L in SLS, 290 +/- 39 IU/L in SLS + chlorpromazine, 1 mg/L, 290 +/- 11 IU/L in SLS + chlorpromazine, 10 mg/L. The values for the SLS + chlorpromazine were significantly lower than for SLS and UW (p less than 0.05). The pH of the effluent was 7.10 +/- 0.10 in controls, 6.42 +/- 0.12 in UW, 6.64 +/- 0.18 in SLS, and 7.07 +/- 0.02 in SLS + chlorpromazine, 1 mg/L and 10 mg/L. The pH drop was significantly greater in the groups without chlorpromazine (p less than 0.01). This study shows that superior rat liver preservation was achieved with a simplified lactobionate solution containing sodium as the principal cation, sucrose in place of raffinose, and omitting the colloid and several of the other UW components. The addition of low concentrations of chlorpromazine further enhanced the effectiveness of this solution, without the need for donor pretreatment.

Adenosine↗
PubMed1992

Carrier detection for Sjögren-Larsson syndrome.

Sjögren-Larsson syndrome (SLS) is an autosomal recessive disorder associated with reduced activity of the fatty alcohol: NAD+ oxidoreductase complex (FAO). Recent studies indicate that SLS patients are specifically deficient in the fatty aldehyde dehydrogenase (FALDH) component of FAO. To investigate the possibility of carrier detection for SLS, FAO and FALDH activities were measured in cultured skin fibroblasts from normal controls, obligate SLS heterozygotes, and SLS homozygotes using the 18-carbon substrates octadecanol and octadecanal. Three of 11 heterozygotes for SLS had FAO activities that were within the normal range; the other 8 SLS heterozygotes had FAO activities below normal. In contrast, fibroblast FALDH activity was more effective than FAO in discriminating SLS heterozygotes from normal controls. FALDH activity (nmol min-1 (mg protein)-1) in normal controls was 8.54 +/- 1.16 (mean +/- SD; range 6.95-10.77; n = 12) and in SLS heterozygotes was 5.12 +/- 1.31 (range 3.28-6.96; n = 11), or 60 +/- 15% of mean normal activity. One SLS heterozygote had an FALDH activity within the lower range of normal; this heterozygote had an FAO activity below normal. None of the SLS heterozygotes had an FAO or FALDH activity that was in the range of that measured in SLS homozygotes. These results indicate that measurement of FAO and FALDH activities in cultured skin fibroblasts using 18-carbon substrates is useful for SLS carrier detection.

Alcohol Oxidoreductases↗
PubMed1976

Relationship of cellular potential hemolysin in group A streptococci to extracellular streptolysin S.

The relationship of streptolysin S (SLS) and a cellular potential hemolysin (PH) activatable by sonication was examined in strain C203S (a known high producer of SLS), its SLS(-) mutant (C203U), and in 20 other group A streptococci of various M and T serotypes. All strains shown to form SLS (ribobycleic acid (RNA)-core SLS) contained PH. The two strains lacking PH were the only ones that did not produce SLS In strain C203S, formation of SLS bycells incubated with RNA-core for 60 min at 47 C in a nongrowth basal medium (Bernheimer's basal medium) was followed by a marked decrease (99.6% loss) of PH titer. Without stimulation of SLS production by addition of RNA-sore, the same incubation resulted in a progressive but less marked fall (38.8%loss in 60 min) of PH titer: these cells produced disproportionately low titers of SLS on subsequent addition of RNA-core. This effect of prior incubation in Bernheimer's basal medium on SLS titer was partially nullified by use of fresh medium after 30 min, but not after 60 min, and did not occur during 60 min of incubation at OC. These results provide additional evidence for a precursor-product relationship between PH and SLS. They also suggest that a medium factor (or factors) is utilized or destroyed at 37 C and that this factor is essential to both the stability of PH and its efficient conversion to SLS.

Hemolysin Proteins↗
PubMed1988

Reaggregation behavior of different types of collagen in vitro: variations in the occurrence and structure of dimeric segment long-spacing collagen.

Segment long-spacing collagen (SLS) can be precipitated from solutions of collagen using ATP as the inducing agent. Dimeric SLS aggregates have been observed in addition to monomeric SLS. We have compared collagen types I, II, III, and V with respect to their ability to form dimeric SLS in vitro. These collagen types were isolated from bovine tissues and characterized by polyacrylamide slab gel electrophoresis of the respective alpha-chains. Only monomeric SLS can be detected in preparations of collagen types I and III. Dimeric SLS, on the other hand, accounts for the majority of the crystallites seen in preparations of collagen types II and V. Dimeric SLS from both collagen types II and V reveal overlap zones at the carboxy-terminal ends of the collagen molecules. However, dimeric SLS from collagen types II and V differ with respect to their overlap distances. Significant portions of the triple helical domains of collagen molecules are occupied by the overlap region of dimeric SLS from type II collagen. On the other hand, dimeric SLS from type V collagen is composed of molecules overlapping only at their short nonhelical telopeptides. It is concluded that the ability of collagen molecules to aggregate into dimeric SLS under defined experimental conditions is collagen type dependent.

Adenosine Triphosphate↗
PubMed1988

Sjögren-Larsson syndrome. Impaired fatty alcohol oxidation in cultured fibroblasts due to deficient fatty alcohol:nicotinamide adenine dinucleotide oxidoreductase activity.

Lipid metabolism was studied in cultured skin fibroblasts from patients with the inherited disorder, Sjögren-Larsson syndrome (SLS). Intact SLS fibroblasts incubated in the presence of [1-14C]palmitate accumulated more radioactive hexadecanol than did normal cells, whereas incorporation of radioactivity into other cellular lipids was unaltered. The hexadecanol content of SLS fibroblasts was abnormally elevated. Hexadecanol accumulation was not due to increased fatty alcohol synthesis nor its deficient utilization for glycerol ether synthesis. The half-life of intracellular hexadecanol loaded into SLS fibroblasts was increased (70 min) compared with normal (15 min), and intact SLS fibroblasts showed impaired oxidation of [14C]-hexadecanol to fatty acid. Fatty alcohol:NAD+ oxidoreductase, the enzyme catalyzing this reaction, was deficient in SLS fibroblasts. Mean total activity in SLS fibroblasts (n = 5) was 13% of that in normal fibroblasts, and palmitoyl CoA-inhibitable activity was 1% of normal. Fibroblasts from two obligate SLS heterozygotes had enzyme activities intermediate between that in normal fibroblasts and individuals with SLS. These results suggest that the primary defect in SLS is deficiency of fatty alcohol:NAD+ oxidoreductase. SLS represents the first inherited disorder in man associated with an isolated abnormality in fatty alcohol metabolism.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1991

Sjögren-Larsson syndrome. Deficient activity of the fatty aldehyde dehydrogenase component of fatty alcohol:NAD+ oxidoreductase in cultured fibroblasts.

Sjögren-Larsson syndrome (SLS) is an inherited disorder associated with impaired fatty alcohol oxidation due to deficient activity of fatty alcohol:NAD+ oxidoreductase (FAO). FAO is a complex enzyme which consists of two separate proteins that sequentially catalyze the oxidation of fatty alcohol to fatty aldehyde and fatty acid. To determine which enzymatic component of FAO was deficient in SLS, we assayed fatty aldehyde dehydrogenase (FALDH) and fatty alcohol dehydrogenase in cultured fibroblasts from seven unrelated SLS patients. All SLS cells were selectively deficient in the FALDH component of FAO, and had normal activity of fatty alcohol dehydrogenase. The extent of FALDH deficiency in SLS cells depended on the aliphatic aldehyde used as substrate, ranging from 62% of mean normal activity using propionaldehyde as substrate to 8% of mean normal activity with octadecanal. FALDH activity in obligate SLS heterozygotes was partially decreased to 49 +/- 7% of mean normal activity using octadecanal as substrate. Differential centrifugation studies in fibroblasts indicated that this FALDH enzyme was largely particulate; soluble FALDH activity was normal in SLS cells. Intact SLS fibroblasts oxidized octadecanol to fatty acid at less than 10% of the normal rate, but oxidized free octadecanal normally, suggesting that the FALDH affected in SLS is chiefly involved in the oxidation of fatty alcohol to fatty acid. These results show that the primary enzymatic defect in SLS is the FALDH component of the FAO complex, which leads to deficient oxidation of fatty aldehyde derived from fatty alcohol.

Alcohol Oxidoreductases↗
PubMed1992

Noninvasive measuring methods for the investigation of irritant patch test reactions. A study of patients with hand eczema, atopic dermatitis and controls.

The aim of the study was to assess the susceptibility of clinically normal skin to a standard irritant trauma under varying physiological and patophysiological conditions. Evaluation of skin responses to patch tests with sodium lauryl sulphate (SLS) was used for assessment of skin susceptibility. The following noninvasive measuring methods were used for evaluation of the skin before and after exposure to irritants: measurement of transepidermal water loss by an evaporimeter, measurement of electrical conductance by a hydrometer, measurement of skin blood flow by laser Doppler flowmetry, measurement of skin colour by a colorimeter and measurement of skin thickness by ultrasound A-scan. The studies were carried out on healthy volunteers and patients with eczema. In the first studies the standard irritant patch test for assessment of skin susceptibility was characterized and validated. SLS was chosen among other irritants because of its ability to penetrate and impair the skin barrier. The implications of use of different qualities of SLS was investigated. The applied noninvasive measuring methods were evaluated, and for quantification of SLS-induced skin damage measurement of TEWL was found to be the most sensitive method. Application of the standard test on clinically normal skin under varying physiological and patophysiological conditions lead to the following main results: Seasonal variation in skin susceptibility to SLS was found, with increased susceptibility in winter, when the hydration state of the stratum corneum was also found to be decreased. A variation in skin reactivity to SLS during the menstrual cycle was demonstrated, with an increased skin response at day 1 as compared to days 9-11 in the menstrual cycle. The presence of active eczema distant from the test site increased skin susceptibility to SLS, indicating a generalized hyperreactivity of the skin. Taking these sources of variation into account healthy volunteers and patients with hand eczema and atopic dermatits were studied and compared. In healthy volunteers increased baseline TEWL and increased light reflection from the skin, interpreted as "fair" skin, was found to be associated with increased susceptibility to SLS. Hand eczema patients were found to have fairer and thinner skin than matched controls. Increased susceptibility to SLS was found only in patients with acute eczema. Patients with atopic dermatitis had increased baseline TEWL as well as increased skin susceptibility as compared to controls. Skin susceptibility is thus influenced by individual- as well as environment-related factors. Knowledge of determinants of skin susceptibility may be useful for the identification of high-risk subjects for development of irritant contact dermatitis, and may help to prevent the formation of the disease.

Colorimetry↗
PubMed1989

Plaque inhibition by a combination of zinc citrate and sodium lauryl sulfate.

Bacteriological tests demonstrated an additive inhibitory effect of ZnCl2 and sodium lauryl sulfate (SLS) on in vitro growth of Streptococcus sobrinus OMZ 176 and of Streptococcus sanguis ATCC 10556. As measured by atomic absorption spectrophotometry, the solubility of zinc citrate increased in the presence of SLS. After 48 h, the concentration of solubilized zinc from aqueous solutions of 5.0 mM zinc citrate was 12.0 mM versus 14.4 mM in the presence of 34.7 mM SLS. The plaque-inhibiting properties of aqueous solutions of 12.0 mM Zn2+ from zinc citrate, 34.7 mM SLS, and 14.4 mM Zn2+ from zinc citrate in combination with 34.7 mM SLS were examined in 7 volunteers. Plaque accumulations were assessed by using a method earlier described after 3 days of twice daily mouthrinses with 10 ml test solution, during which period no mechanical oral hygiene was performed. Compared to placebo, SLS and zinc citrate increased the frequency of plaque index score 0 by 52.9 and 98.3%, respectively, and SLS gave 36.9% and zinc citrate 55.7% less surfaces with scores 2 or 3 (p less than 0.05 in all cases). The combination of zinc citrate and SLS gave a threefold increase of plaque index score 0 and a 70.5% reduction of scores 2 or 3 (p less than 0.05).

Chemical Phenomena↗
PubMedDate not supplied

pH influence of surfactant-induced skin irritation. A non-invasive, multiparametric study with sodium laurylsulfate.

Even though various experimental methods have been proposed for in vitro testing of detergents such as LSL (sodium laurylsulfate) no absolutely relevant clinical information can be inferred from them as to the irritancy of a given compound. In particular the relative importance of pH needs further assessment. This study reports on in vivo evaluation of skin function changes under given experimental conditions with SLS applied at 3 different pH values. There is a dramatic increase of transepidermal water loss (TEWL), i.e. a substantial reduction in the barrier function of the skin, when SLS is applied under occlusion for 48 H. The alkaline control solution (NaOH pH 9) induced low-grade, but significant TEWL increases, as compared to the other controls (distilled water pH 7; HCl pH 5), which had no influence on TEWL. The changes obtained with the controls were much lower than those observed with SLS. The barrier-function changes induced by the surfactant SLS could, however, promote transepidermal passage of acid and/or alkaline molecules, hence increasing toxic damage of the skin; yet no such effects could be observed, indicating that the main effects are due to detergency. Assessment of cutaneous blood flow values (CBFV) by laser Doppler velocimetry showed increased values after SLS. When pH-adjusted SLS solutions were compared, there was neither a difference in relation to pH nor did the control solutions induce any significant CBFV change. This study reveals that TEWL and CBFV are probably the most reliable methods to investigate acute irritancy by SLS. Accordingly, pH cannot be considered as a major contributive factor of irritancy when SLS solutions are applied under occlusion (48 h).(ABSTRACT TRUNCATED AT 250 WORDS)

Acid-Base Equilibrium↗
PubMed1990

Stem-loop structures at the 3' end of tobacco Rubisco large subunit mRNA.

There are two inverted repeat nucleotide (nt) sequences, each capable of forming a stem-loop structure (sls) at the 3' end of the tobacco Rubisco large subunit mRNA (rbcL). The smaller sls is followed by a larger sls. The in vivo functions of the 3' sls of the rbcL mRNA were characterized using the Escherichia coli system. S 1 mapping of the rbcL transcripts synthesized in E. coli revealed that the 3' end of a major transcript in the bacterial cell is almost identical to the 3' end of authentic chloroplast (cp) rbcL mRNA. This native 3' end is located 4 nt downstream from the larger sls for the cp mRNA and 6 nt for the bacterial transcript, respectively. Deletion experiments show that the larger sls is essential for producing the native 3' end of rbcL mRNA in E. coli. The sls do not function as an efficient transcription terminator but can stabilize upstream mRNA segments in vivo.

Base Sequence↗