Controlled trial of the effects of 1,25-dihydroxycholecalciferol in patients treated with regular dialysis

In a double-blind controlled study, 15 patients received 1,25-dihydroxycholecalciferol (1,25[OH]2D3) (0.5-1.5 microgram/day) and 16 patients received vitamin D3 (D3) (400-1,200 IU/day). The patients receiving 1,25(OH)2D3 had a rise in mean serum calcium concentration from 9.05 +/- 0.15 to 10.25 +/- 0.20 mg/dl (p less than .001) with a return to 9.37 +/- 0.16 (p less than .001) in the post-control period; however, hypercalcemia (greater than 11.5 mg/dl) occurred in 5 of 15 patients. Likewise, patients who received 1,25(OH)2D3 but not those given D3 had a reversible decrease in immunoreactive parathyroid levels. 9 of 12 patients given D3 had serial iliac crest bipsies showing histologic deterioration, while 6 of 7 patients who received 1,25(OH)2D3 were improved or unchanged (p less than 0.025). Bone mineral and calcium content decreased in patients on D3 (p less than .05) but not in those on 1,25(OH)2D3. We conclude that the administration of 1,25(OH)2D3 to dialysis patients: (1) has a calcemic effect. (2) decreases levels of immunoreactive parathyroid hormone, and (3) is associated with histologic improvement in bone disease.

Lipid peroxide of human skin

Lipid peroxide in human skin surface lipids was investigated. The correlation between the amount of lipid peroxide and the total amount of lipids in skin surface lipids was determined by statistical analysis. Furthermore, the correlation between lipid peroxide and squalene in skin surface lipids was also proved. These results suggest that the major source of lipid peroxide in skin surface is squalene, and that lipid peroxidation is enhanced by external factors such as ultraviolet light irradiation.

Deposits of plasma proteins in the skin during treatment with carbamazepine and diphenylhydantoin

Biopsies from skin of normal appearance from 18 patients treated with carbamazepine and diphenylhydantoin were investigated by a direct immunofluorescence technique. Seventeen had deposits of plasma proteins at the dermoepidermal junction, 16 had deposits in the vessel walls, and one had autofluorescence of the nuclei in the epidermis and vessel walls. These findings did not correlate with changes in serum IgG, IgA, IgM, IgD, IgE or alpha 2-macroglobulin. Eight patients had elevated alkaline phosphatase, 4 elevated IgG and one elevated IgA. Three had low values of IgA, and all had normal values of IgM, IgD and IgE, and blood cells. In three patients, carbamazepine was withdrawn, whereupon the deposits disappeared in two and decreased in the third, who changed to another drug. The changes were quantitatively and qualitatively similar to those seen in systemic lupud erythematosus induced by these drugs.

Cathepsin D: specificity of peptide-bond cleavage in type-I collagen and effects on type-III collagen and procollagen

1. Cathepsin D, purified from bovine thymus, has a limited proteolytic effect on types I and III bovine collagens. The alpha 1 (I) chain was cleaved in native or denatured collagen only within the carboxy-terminal extra-helical sequence, the major site being between resides C6 (Leu) and C7 (Ser). The alpha 2 chain was unaffected in native collagen but was slowly cleaved between residues 782 (Phe) and 783 (Leu) in the denatured form. Cleavages, at 45 degrees C, in type III collagen occur within the extra-helical amino-terminal sequence, on the carboxy-terminal side of the lysine residue involved in intermolecular cross-linking. All three sites of action are within sequences of general hydrophobic character. 2. The very restricted cleavage of peptide bonds in denatured collagens can be ascribed to the infrequent occurrence of groupings of more than two hydrophobic residues and to the high content of the conformation-limiting residues proline and hydroxyproline. 3. The previously demonstrated failure of cathepsin D to solubilize a representative proportion of type III collagen from the fibres of bovine skin collagen [P.G. Scott and C.H. Pearson (1978) Biochem, Soc, Trans. 6, 1197-1199] may be explained by lack of ability of the enzyme to act on this collagen at 25 degrees C, in such a manner as to separate molecules joined by intermolecular cross-links involving the amino-terminal extrahelical region of the molecule.

Complementary expression of melanosomal antigens and constant expression of pigment-independent antigen during the evolution of melanocytic tumours

We have generated monoclonal antibodies (MoAbs) against melanosomal proteins (MoAb 1C11 and MoAb HMSA-1) and a cytoplasmic protein strongly synthesized in neoplastic melanocytes but not associated with melanogenesis (MoAb 7H11). An immunohistochemical study of paraffin sections showed that nearly 90% of epidermal neoplastic melanocytes, including melanomas, expressed 1C11 antigen, whereas this antigen was poorly preserved in dermal melanocytic cells except melanomas. HMSA-1 antigen was expressed in a complementary manner to 1C11 antigen, being found in dermal naevus cells but not generally in the epidermal regions, except for dysplastic naevi and melanomas. In contrast, 7H11 antigen was distributed in nearly 90% of melanocytic tumours except solar lentigo and lentigo maligna lesions. The failure of MoAb 1C11 to react with dermal melanocytes may reflect a subtle alteration in melanogenesis during tumour evolution. Overall, the combined use of MoAbs serves as an accurate diagnosis of melanocytic tumours, the pigment-independent MoAb 7H11 being particularly useful for amelanotic and metastatic lesions.

Immunohistochemical study of the abnormal cells in Langerhans cell histiocytosis (histiocytosis x)

The immunophenotypic properties of the abnormal cells in routine specimens from 16 cases of Langerhans cell histiocytosis (LCH) were examined. In five cases, cryostat sections were also available. The abnormal cells expressed a similar phenotype and were positive for HLA-DR, S-100 protein, peanut agglutinin (PNA), CD1a, CD4 and several macrophage-associated markers, including CD11c, CDw32 and CD68 (the latter detectable in routine sections with antibody KP1). Staining with CD14, CD35 (C3b receptor), and CD11b (C3bi receptor) was negative with the exception of one of the cases in which a proportion of the cells showed faint positivity with CD11b. Staining for pan-T-cell (CD2, CD3, CD5) and pan-B-cell (CD19, CD22) antigens was negative in all lesions. It is concluded that LCH expresses a characteristic phenotype with some heterogeneity with regard to macrophage markers and that immunohistochemical methods in cryostat sections and routine specimens form a useful supplement to other techniques for the diagnosis of this condition.

Effects of aging and xerosis on the amino acid composition of human skin

Amino acid compositions of skin samples from young and old subjects and from age-matched donors with dry skin syndrome (xerosis) were examined. The amino acid contents of the free amino acid (FAA) fraction, soluble hydrolysate (SH) fraction, and whole cell hydrolysate (WCH) were determined. The greatest differences were observed between the FAA compositions of the young and old normal subjects. Xerosis did not appear to affect the amino acid compositions of samples from young subjects as much as old subjects. Overall, the effect of aging on the amino acid contents was more pronounced than the effect of xerosis. The amino acid composition of the FAA showed a high degree of similarity to filaggrin, whereas the WCH showed a similarity to keratin.

A critical crosslink region in human-bone-derived collagen type I. Specific cleavage site at residue Leu95

Collagen was extracted from human adult bone by limited pepsin digestion and collagen types were purified by consecutive salt precipitation first under neutral and then under acid conditions. In SDS/PAGE, all collagen type I preparations showed a protein band [alpha 1s(I)] migrating between alpha 1(I) and alpha 2(I) as well as a band [alpha 2s(I)] migrating in front of alpha 2(I). The collagenous nature of the pepsin-stable alpha 1s(I) protein was clearly demonstrated by digestion with human-leucocyte-derived collagenase, immunoblotting with antibodies against collagen type I and amino acid analysis. Partial amino acid sequencing of alpha 1(I) and alpha 1s(I) identified alpha 1s(I) as a shortened alpha 1(I) chain due to a specific cleavage site between residues Leu95 and Asp96 which is in close vicinity to the hydroxylysine-derived crosslink at position 87. In circular dichroism, the proportion of thermally labile collagen molecules was proportional to the amount of shortened alpha 1(I) and alpha 2(I) chains, respectively. The melting temperature was found to be 36 +/- 0.5 degrees C as judged from circular dichroism and susceptibility to proteolysis. Our data provide clear evidence that a shortened alpha 1-derived collagen chain can be extracted from human adult bone whereas it is hardly found in human skin. The unique cleavage site might provide important information about the collagen I molecule embedded in the calcified matrix of human bone.

Cutaneous interstitial fluid protein concentrations in the inflammatory syndrome: pharmacological consequences

Concentrations of alpha 1 acid glycoprotein, albumin, transferrin, haptoglobin, immunoglobulins G, A, M and apolipoprotein B were measured in serum and suction blister fluid from a group of individuals presenting a biologically proven inflammatory syndrome, and from a control group. Protein values in suction blister fluid did not change from the 2nd to the 3rd h after the beginning of blister formation. The ratio of the concentration of proteins in blister fluid and serum did not differ significantly between the groups. However, a 25% decrease in blister fluid albumin and a 100% increase in blister fluid alpha 1 acid glycoprotein, recorded in the inflammatory group, were worth noting, since they possibly influence the tissular distribution of some protein-binding drugs. Finally, an inverse relationship was established between the blister fluid/serum concentration ratio and the respective molar mass of each protein.

Immunohistologic abnormalities of the microfibrillar-fiber system in the Marfan syndrome

BACKGROUND

Indirect-immunofluorescence studies of skin and cultured dermal fibroblasts from patients with the Marfan syndrome demonstrate apparent deficiency of one element of connective tissue--the microfibrillar-fiber system--in assays using specific antibodies against fibrillin, a major microfibrillar protein. This study was designed to test whether these immunostaining abnormalities are consistent and diagnostic features of the disease.

METHODS

We studied patients with either the Marfan syndrome or various other inherited connective-tissue disorders and normal subjects according to a single-blind protocol in which coded samples of skin, fibroblast cultures, or both were analyzed without knowledge of the clinical diagnosis and classified as "Marfan" or "non-Marfan" before the sample codes were broken.

RESULTS

Of the 27 patients with the Marfan syndrome, 24 were correctly identified by the decreased content of microfibrillar fibers in their skin, cultured fibroblasts, or both; in contrast, 19 of 25 patients with other heritable disorders of connective tissue and all 13 normal subjects were correctly classified as "non-Marfan" by these assays (P less than 0.001).

CONCLUSIONS

These results document consistent, relatively specific abnormalities of microfibrillar fibers in the Marfan syndrome. The biomechanical incompetence of these structural elements, due to quantitative or qualitative abnormalities, may account for the pleiotropic clinical manifestations of the disease. Therefore, various defects in the expression, structure, assembly, or degradation of the constituent structural glycoprotein (or glycoproteins) of microfibrils may be implicated in the causation of the Marfan syndrome.

Properties and nature of a cysteine proteinase inhibitor located in keratohyalin granules of rat epidermis

The pI 4.7, 14.5 kDa hematoxylin-stainable protein (HSP) from rat epidermis inhibited the activities of the cysteine proteinases papain, ficin, cathepsins B, H and L with similar inhibitory characteristics as recombinant cystatin-alpha. Proteinases of other classes were not inhibited. The inhibitory activity of HSP was heat stable in the wide pH range of 3.0-10.0. Polyclonal antibodies against HSP cross-reacted with cystatin-alpha and the molecular mass of HSP was similar to that of cystatin-alpha, though its isoelectric point was different. The in vivo location of both HSP and cystatin-alpha is on keratohyalin granules in epidermis as detected by indirect immunofluorescence technique using individual antibodies. Therefore it is highly probable that HSP is a cystatin-alpha derivative or a very similar proteinase inhibitor belonging to a family of cystatins.

A method for the sequence analysis of dermatan sulphate

We are attempting to develop methods for the sequencing of glycosaminoglycans from their reducing end. Here we describe a procedure for the analysis of dermatan sulphate from pig skin. The glycosaminoglycan is released from its parent proteoglycan by exhaustive proteolysis by using both endo- and exo-peptidases. The amino group of the residual serine residue is conjugated with a p-hydroxyphenyl group, which in turn is iodinated with 125I (the Bolton-Hunter reagent, BHR). The ion-exchange-purified end-labelled dermatan sulphate is then degraded partially or completely by various enzymic or chemical means to yield fragments extending from the labelled serine residue to the point of cleavage. The various products are separated by gradient PAGE, detected by autoradiography and quantified by videodensitometry. Complete digestion with chondroitin ABC lyase affords the labelled fragment delta HexA-GalNAc(-SO4)-GlcA-Gal-Gal-Xyl-Ser(-BHR). The structure was confirmed by sequential degradation from the non-reducing end by chondroitin AC lyase, HgCl2, and beta-galactosidase. Periodate oxidation cleaves most of the Xyl even without treatment with alkaline phosphatase, showing that Xyl is not substituted with phosphate. Results from partial and selective periodate oxidation indicate that most of the non-sulphated IdoA residues are located towards the non-reducing end. Partial or complete digestions with testicular hyaluronidase (in the presence of an excess of beta-glucuronidase) or chondroitin AC lyase identify the positions of GlcA residues. The results confirm that HexA next to Gal is always GlcA. Moreover, GlcA is common in the first three disaccharide repeats. Results with testicular hyaluronidase indicate that the distribution of clustered GlcA-GalNAc repeats is periodic and peaks at positions 1-3, 8-9 and around 25. Although there must be chains that contain IdoA in nearly all of the available positions, regions that have not been fully processed during biosynthesis are markedly non-random.

In the absence of a downstream element, the apolipoprotein E gene is expressed at high levels in kidneys of transgenic mice

Human apolipoprotein (apo) E gene constructs with 30 or 5 kilobases of 5'-flanking and 1.5 kilobases of 3'-flanking regions were used to create transgenic mice. High levels of human apoE mRNA were present in the transgenic kidney, but none was detected in the liver, which is normally the major source of apoE. When a construct with 5 kilobases of 5'- and 23 kilobases of 3'-flanking regions was used, only trace levels of human apoE mRNA were detected in the kidney, whereas high levels were found in the liver. These results indicated that regulatory elements downstream of the human apoE gene interacted with the transcription initiation complex to stimulate gene expression in the liver while suppressing expression in the kidney. In each case, human apoE was secreted into the plasma. The source of human apoE in the transgenic kidney was the epithelial cells lining the proximal tubule and Bowman's capsule.

Association of EGF receptor expression with proliferating cells and of ras p21 expression with differentiating cells in various skin tumours

The localization of DNA replicating cells, epidermal growth factor (EGF) receptor-expressing cells and ras oncogene product p21 (p-21ras) positive cells were examined in various skin tumours to elucidate the role of EGF receptor and p21ras in the epidermis. Normal skin, keratoacanthoma (KA), solar keratosis (SK), Bowen's disease (BD), squamous cell carcinoma (SCC), basal cell carcinoma (BCC) and extramammary Paget's disease (PD) were studied. EGF receptors were seen in proliferating layers, where DNA replicating cells localize, but p21ras was found in the more differentiated layers. We conclude that EGF receptor expression is closely associated with cellular proliferation, but p21ras may play a role in the differentiation of cells in various skin tumours.

Essential fatty acid nutrition of the American alligator (Alligator mississippiensis)

The essential fatty acid (EFA) nutrition of young American alligators (Alligator mississippiensis) was examined by feeding a variety of fats/oils with potential EFA activity. Over a 12-wk period, alligators fed diets containing 2.5 or 5.0% chicken liver oil grew longer and heavier and converted feed to body mass more efficiently than alligators fed other fat/oil combinations that lacked or contained only trace amounts of arachidonic acid [20:4(n-6)]. Alligators fed an EFA-deficient diet (containing only coconut fat as the dietary fat) were the slowest-growing animals and converted feed to body mass least efficiently. However, over a 41-wk feeding period, alligators fed this diet showed no obvious external signs of deficiency other than being reduced in size and unthrifty. Fatty acid composition of heart, liver, muscle, skin and adipose tissue lipids was influenced markedly by dietary fat composition. Tissues varied significantly in response to dietary fat composition. Heart lipids contained the lowest levels of short- and medium-chain fatty acids and the highest levels of arachidonic acid. Arachidonic acid levels were less influenced by diet than were levels of other 20- and 22-carbon polyunsaturated fatty acids. Radiotracer studies indicated that linoleic acid was converted to arachidonic acid in the liver. Nevertheless, tissue arachidonic acid levels also appeared to be maintained by concentration from dietary sources and selective conservation. It appears that a dietary source of arachidonic acid may be required for a maximum rate of growth.

In situ detection of basic fibroblast growth factor by highly specific antibodies

Basic fibroblast growth factor (bFGF) is thought to be of major importance for fibrosis and angiogenesis. Despite intensive studies dealing with the biochemistry and multiple biologic effects of bFGF, the cellular distribution is virtually unknown. Therefore, using the indirect immunoperoxidase technique, we examined the effect of bFGF on a large pattern of normal, inflammatory, and tumorous human tissues. Staining was performed on cryostat sections with a highly specific affinity-purified antiserum. In normal tissues, especially those of the thymus and placenta, mainly dendritic cells contained the growth factor. High levels of bFGF were also detected in basal cells and gland epithelial cells of skin biopsies. A conspicuous expression was observed in chronic inflammatory tissues corresponding to a generally pronounced proliferation of fibroblasts and endothelial cells in these situations. Tumors revealed a very heterogenous staining pattern. In some lesions, bFGF was predominantly present in infiltrating and endothelial cells. In several, neoplasms tumor cells exhibited an intensive staining. In some, especially vascular tumors, bFGF could not be detected. From the staining results it is concluded that angiogenesis is not simply controlled by the presence of bFGF but is mediated by a balance of several angiogenic inducers and inhibitors.

Human type VI collagen: isolation and characterization of alpha 1 and alpha 2 chains by two-dimensional preparative gel electrophoresis

Two 140 kDa collagenous glycoproteins were isolated from 5 M guanidinium chloride extracts of human uterine leiomyoma by two-dimensional preparative gel electrophoresis. The glycoproteins represented the major concanavalin A binding fraction of the extract and were also present in adult human skin. On two-dimensional gel electrophoresis the glycoproteins appeared as elongated spots, indicating variations of their isoelectric points from 5 to 6. These glycoproteins were disulfide-bonded components of high molecular mass protein and, after reduction, became sensitive to collagenase treatment that generated peptides corresponding in size to those of the noncollagenous domains of type VI collagen. Antisera raised against these purified glycoproteins reacted with either pepsin-derived alpha 1(VI) or pepsin-derived alpha 2(VI) chains but not with alpha 3(VI) chain of human type VI collagen. Reciprocally, these glycoproteins reacted with monoclonal antibodies against type VI collagen. These results indicate that the glycoproteins represent the integral alpha 1 and alpha 2 chains of type VI collagen. The globular domains of alpha 1(VI) and alpha 2(VI) chains remaining after collagenase treatment appeared on two-dimensional gel electrophoresis as elongated spots, suggesting that the noncollagenous portions determine the well known microheterogeneity of the molecule. The differences in isoelectric points between and within alpha chains may facilitate the formation of microfibrillar network.

Neuropeptides in skin from patients with atopic dermatitis: an immunohistochemical study

The distribution and localization of several neuropeptides were investigated in the lichenified lesions of 11 patients with atopic dermatitis using indirect immunofluorescence. Substance P-positive nerve fibres were observed in most of the cases of atopic dermatitis, but not in normal controls. Somatostatin immunoreactive nerves were not found in the skin of atopic dermatitis, whereas a normal pattern of immunoreactivity could be detected in most of the healthy subjects. Neuropeptide Y-positive dendritic epidermal cells were observed in lesional skin from patients with atopic dermatitis, but not in controls. Calcitonin gene-related peptide and vasoactive intestinal polypeptide immunoreactivity in patients with atopic dermatitis did not differ from that in healthy subjects. With galanin antiserum a diffuse intracellular staining was observed in the epidermis of both atopic patients and controls, while no positive staining was found with either neurotensin or neurokinin A antibodies in either group. These findings suggest a possible involvement of some neuropeptides in the pathomechanisms of atopic dermatitis.

Noninvasive measurements of bilirubin in the newborn

Technologic advances have allowed a means for more precise measurement of cutaneous bilirubin. These advances have led investigators to examine the correlation between cutaneous and blood bilirubin in hopes of either replacing or reducing the number of serum bilirubin values obtained. In the past other investigators attempted to do the same, using visual estimates of jaundice with and without the help of reference devices. The establishment of an acceptable correlation between cutaneous and serum bilirubin requires (1) accurate measurement of serum bilirubin, (2) accurate measurement of cutaneous bilirubin, and (3) steady-state conditions between the blood-cutaneous bilirubin "compartments." The accuracy with which cutaneous bilirubin can be measured appears similar or better than that with which serum bilirubin is measured; with older transcutaneous devices significant interobserver variability may exist. Bias in the form of other skin chromogens also interferes with accuracy. Rapid changes in serum or cutaneous bilirubin concentration or nonhomogeneous distribution of cutaneous bilirubin interferes with our knowledge of cutaneous-blood bilirubin kinetics. At present transcutaneous bilirubinometry cannot replace routine serum measurements, but both new and old transcutaneous devices can serve as effective screening devices. The choice of which device to use depends on its cost-effectiveness in any given clinical setting.

Characterisation of xenopsin immunoreactivity derived from pepsinised human skin and possible mechanism of in vivo generation

Human skin was subjected to a variety of extraction and enzymatic digestion procedures. Extracts and digests were subjected to neurotensin and xenopsin radioimmunoassays of known specificity. No neurotensin immunoreactivity was detected in any preparation with any region-specific antiserum. C-terminal xenopsin immunoreactivity was present in skin homogenates following incubation with both soluble and solid-phase pepsin and in those incubated with a leucocyte lysate or purified cathepsin D. The generation of xenopsin immunoreactivity was dependent on low pH and enzymes of pepsin-type specificity acting on a tissue precursor of approximately 30 kDa. Gel permeation chromatography of skin-derived xenopsin immunoreactivity identified a single molecular species larger than synthetic xenopsin which was resolved into two components by reverse-phase HPLC with retention times similar to synthetic xenopsin and kinetensin. Human skin thus contains a high-molecular-weight precursor protein and an endogenous acid protease, cathepsin D, capable of generating a peptide of similar size and C-terminal structure to amphibian xenopsin under acidic conditions such as might occur locally in wounds or at sites of inflammation.

Skin zinc concentrations in patients with varicose ulcers

The concentration of zinc in the skin has been determined noninvasively in patients with varicose vein ulcers. The examinations were performed with the use of diagnostic x-ray spectrometry, a method based on x-ray fluorescence for in vivo noninvasive evaluation of trace elements. Four skin foci were examined: at the periphery of the ulcer and control areas in a nonulcerated area in the diseased leg, in the noninvolved leg, and in the proximal inner surface of the arm. Zinc levels around the ulcer (mean +/- SD, 9.8 +/- 4.0 micrograms of zinc in 1 g of wet tissue) were higher than those in the nonulcerated skin in the diseased leg (6.9 +/- 3.0 micrograms/g, p greater than 0.05) and those in the noninvolved leg (5.4 +/- 2.0 micrograms/g, p less than 0.01). The concentration of zinc in the inner proximal surface of the arm (9.8 +/- 2.8 micrograms/g) was significantly higher than those of a control group (5.3 +/- 1.9 micrograms/g, p less than 0.01). These results suggest a defect of zinc distribution in patients with varicose vein ulcers.

Analysis of cultured chorionic villi in a case of osteogenesis imperfecta type II: implications for prenatal diagnosis

We examined collagens produced by cultured cells from skin, chorionic villi, and placental membranes of a 32 week fetus with osteogenesis imperfecta (OI) type II. We observed that skin fibroblasts synthesized two populations of pro alpha 1(I) chains of type I procollagen; one population was normal, while the other population had excessive post-translational modification. The thermal stability of helices containing the overmodified chains was reduced 1-2 degrees C. Most significantly, the cells cultured from chorionic villi produced type I collagen chains with the same electrophoretic abnormalities as the skin collagen. This suggests that chorionic villus sampling (CVS) is a means of prenatal diagnosis for families with a previous type II or type IV OI infant.

A study of beta 2-microglobulin skin deposits in dialyzed patients and healthy controls

This study reports on beta 2-microglobulin (beta 2M) deposits in the skin of 12 uremic patients and three kidney transplant recipients compared with eight healthy controls. Uremic patients were treated by hemodialysis (HD), hemofiltration (HF), hemodiafiltration (HDF), or continuous ambulatory peritoneal dialysis (CAPD) for a period lasting from 1 to 19 years. Congo red staining of the skin was negative in patients and controls. However, immunofluorescent staining with an anti-beta 2-microglobulin monoclonal antibody was positive in the skin of all patients and of six of the eight controls. Beta 2M skin deposition is more intense in patients than in controls and increases with patient age and the duration of dialysis. A stron correlation is observed between the extent of skin beta 2M deposits and clinical manifestations due to beta 2M deposits in internal organs. However, no correlation is found between beta 2M skin deposits and sex or beta 2M serum levels.

Partial characterization of dermatan sulfate by proton nuclear magnetic resonance spectroscopy

The degree of galactosamine N-acetylation, iduronic acid composition, and total uronic acid/hexosamine ratios of the three dermatan sulfates of human skin, DS18, DS28, and DS35 (M. O. Longas et al. (1987) Carbohydr. Res. 159, 127-136), were determined by Fourier transform, proton nuclear magnetic resonance (FT 1H NMR) spectroscopy. Analysis of DS of varying ages was conducted at 400 MHz and 60 degrees C. Chemical shifts for H-1, H-2, H-4, and H-5 of L-IdUA were independent of those for the respective protons of D-GalNAc and D-GlcUA. The resonance intensities of H-1 and acetamido methyl protons of D-GalNac did not display the expected 1:3 ratios. Therefore, their integration values were employed to estimate the percentage N-acetylation (N-CH3/3 H-1) which was corroborated chemically. The L-IdUA content, relative to total uronic acid, was calculated from signal intensities of H-1 of L-IdUA and D-GlcUA and ascertained by quantitative chemical methods. Total uronic acid/hexosamine ratios were determined from both 1H NMR spectroscopy and chemical analyses. The data show the following N-acetylation (N-CH3/3 H-1) of galactosamine in DS:DS18, 61-72% between 17 and 60 years, unaffected by senescence; DS28, 78-86% with no age-related trend; DS35, 101% at 19 years. Furthermore, in all ages investigated, the percentage (wt/wt) L-IdUA relative to total uronic acid was 42-44% for DS18 and 37-40% for DS28. At age 19 years, DS35 had a 29% (wt/wt) L-IdUA. The total uronic acid/hexosamine ratios for DS18 and DS28 varied from 1.40:1.0 to 1.70:1.0 irrespective of age.

Interleukin 2, soluble interleukin 2 receptor, and interferon-gamma in the suction blister fluids from psoriatic skin

Psoriasis represents inflammatory skin disorders characterized by significant changes in cellular immunity, particularly exhibiting alterations in T lymphocyte-related functions. Early psoriatic lesions have been reported to show an infiltration of activated helper T cells. Elevated levels of interleukin 2 (IL-2), IL-2 receptor (IL-2R), and interferon-gamma (INF-gamma) are associated with an early activation of T cells. To examine local activation of T cells in psoriatic skin, the amounts of activated T cell products, IL-2, secretory form of IL-2R (sIL-2R) and INF-gamma were measured in the fluids of suction blisters raised on psoriatic skin. sIL-2R levels were significantly elevated in the suction blister fluids raised on psoriatic involved skin compared with those on normal and psoriatic uninvolved skin. On the other hand, neither IL-2 or IFN-gamma was detected in the suction blister fluids either from normal, psoriatic uninvolved, or involved skin. However, we could detect IFN-gamma and IL-2 in the psoriatic scale extracts. Although we failed to detect IL-2 and IFN-gamma in the suction blister fluids, the increased levels of sIL-2R in the suction blister fluids from the psoriatic lesional skin indicate local activation of T cells in psoriatic lesional skin.

Effect of amiloride on electrolyte concentrations and rubidium uptake in principal and mitochondria-rich cells of frog skin

The role of mitochondria-rich cells (MR cells) in transepithelial Na transport was investigated by determining electrolyte concentrations and Rb uptake in individual cells of frog skin epithelium using electron microprobe analysis. Measurements were performed under control conditions and after blocking the transepithelial Na transport with amiloride. Under control conditions, Na and Cl concentrations of MR cells scattered much more than those of principal cells and ranged from a few up to more than 30 mmol/kg wet weight. Rb uptake from the basal side into individual MR cells also showed a large variation and was, on the average, much less pronounced than into the principal cells. In principal cells, amiloride reduced the Na concentration and Rb accumulation. In contrast, no effect was observed upon electrolyte concentration and Rb uptake of MR cells. Rb uptake was correlated to the Na concentration of MR cells both under control conditions and after amiloride. It is concluded that, in contrast to the principal cells, MR cells are not involved in amiloride-sensitive transepithelial Na transport and that their Na/K-pump activity is very low.

Crystalline and amorphous gold in chrysiasis

Skin biopsy specimens from five patients (three females and two males) treated parenterally with gold were investigated using transmission electron microscopy. X-ray microanalysis and electron diffraction were used to determine the dermal heavy metal content. Additional sections were stained for light microscopic examination. The amount of elemental gold administered to the patients over a period of years to alleviate rheumatoid arthritis lay between a minimum of 4.0 g and a maximum of 10.0 g. In one and the same patient dermal histiocytic gold aggregations in sun-exposed areas of skin displayed a different pattern and divergent physiochemical states from the gold deposits in non-UV-exposed skin, where aurosome-like amorphous formations are found in the cells of the upper dermis. Additional spherical particles are associated predominantly with phagolysosomes in melanophages beneath solar-irradiated epidermis. Convergent beam electron diffraction proves the crystalline nature of the spherical auriferous deposits. The occurrence of skin rash was not related to different physicochemical states of the precious metal.

Effects of oil and water baths on the hydration state of the epidermis

The effects of bath-oil and tap-water baths were studied by non-invasive bioengineering methods. Measurements of water evaporation, electrical conductance and capacitance demonstrated an increase in cutaneous hydration for 20 min after both types of bath, with the larger increase occurring within the first 10 min. A small but significantly greater amount of water (12-27%) was bound in the skin following use of bath oil. However, measurements of evaporation, conductance and capacitance indicated no clear difference in the skin surface hydration following bath-oil and tap-water baths. Thus, the increase in the water-holding capacity of the skin resulting from bath oil is slight and of no real importance for skin-surface hydration immediately after bathing. There was no difference between 5-min and 20-min baths. Oil baths resulted in an increase in skin-surface lipids lasting at least 3 h, comparable to the effect of traditional moisturizing lotions. This lipidization of the skin surface may have protracted effects. In conclusion, the value of bath oil lies mainly in the general lipidization of the skin with potential improvement in dryness and scaling, i.e. effects which are complex and protracted. The direct hydration of the skin is of short duration and comparable to a tap-water bath. In comparison with lotions, use of an oil bath has the disadvantage that it is not practical for repeated daily treatment over the long period which is necessary for therapy to be effective. The present study on normal skin does not take into account other effects of bathing with or without the addition of oil.

Electrophoretic separation of nucleic acids: evaluation by video and photographic densitometry

The separation of DNA by gel electrophoresis provides a rapid method for determining size distributions of DNA in solution. Densitometric scanning of photographs of gels has been the standard method of analysis of agarose gels. However, analysis of photographs is complicated by the non-linear response of photographic film. Charged-coupled device video cameras have become popular for quantitative densitometry and we have used a charge-coupled device camera to image agarose gels to quantitate DNA damage. We compare video and photographic densitometry for quantitation of ultraviolet radiation (UV)-induced DNA damage and find that the two methods give equivalent results.

Automated image segmentation and serial section reconstruction in microscopy

A technique for automatic 3-D reconstruction of specifically stained features in televised serial histological sections has been developed using an image analyser. Images which included these features were individually converted to binary images, compiled, displayed to show the 3-D morphology and used to quantify the structure. The criteria necessary for producing valid reconstructions and the problems associated with the manipulation of images of fine detail, particularly those containing several thousand features, are illustrated by examples from skin.

Visible-light system for detecting doxorubicin contamination on skin and surfaces

A portable system that uses fluorescence stimulated by visible light to identify doxorubicin contamination on skin and surfaces was studied. When activated by violet-blue light in the 465-nm range, doxorubicin fluoresces, emitting orange-red light in the 580-nm range. The light source to stimulate fluorescence was a slide projector with a filter to selectively pass short-wave (blue) visible light. Fluorescence was both observed visually with viewing spectacles and photographed. Solutions of doxorubicin in sterile 0.9% sodium chloride injection were prepared in nine standard concentrations ranging from 2 to 0.001 mg/mL. Droplets of each admixture were placed on stainless steel, laboratory coat cloth, pieces of latex examination glove, bench-top absorbent padding, and other materials on which antineoplastics might spill or leak. These materials then were stored for up to eight weeks and photographed weekly. The relative ability of water, household bleach, hydrogen peroxide solution, and soap solution to deactivate doxorubicin was also measured. Finally, this system was used to inspect the antineoplastic-drug preparation and administration areas of three outpatient cancer clinics for doxorubicin contamination. Doxorubicin fluorescence was easily detectable with viewing spectacles when a slide projector was used as the light source. The photographic method was sensitive for doxorubicin concentrations from 2.0 to 0.001 mg/mL. Immersion of study materials in bleach for one minute eliminated detectable fluorescence. Doxorubicin contamination is detectable for at least eight weeks in the ambient environment. Probable doxorubicin contamination was detected in two of the three clinics surveyed. A safe, portable system that uses fluorescence stimulated by visible light is a sensitive method for detecting doxorubicin on skin and surfaces.

Differential extraction of keratin subunits and filaments from normal human epidermis

We have investigated keratin interactions in vivo by sequentially extracting water-insoluble proteins from normal human epidermis with increasing concentrations of urea (2, 4, 6, and 9.5 M) and examining each extract by one- and two-dimensional gel electrophoresis, immunoblot analysis using monoclonal anti-keratin antibodies, and EM. The viable layers of normal human epidermis contain keratins K1, K2, K5, K10/11, K14, and K15, which are sequentially expressed during the course of epidermal differentiation. Only keratins K5, K14, and K15, which are synthesized by epidermal basal cells, were solubilized in 2 M urea. Extraction of keratins K1, K2, and K10/11, which are expressed only in differentiating suprabasal cells, required 4-6 M urea. Negative staining of the 2-M urea extract revealed predominantly keratin filament subunits, whereas abundant intermediate-sized filaments were observed in the 4-urea and 6-M urea extracts. These results indicate that in normal human epidermis, keratins K5, K14, and K15 are more soluble than the differentiation-specific keratins K1, K2, and K10/11. This finding suggests that native keratin filaments of different polypeptide composition have differing properties, despite their similar morphology. Furthermore, the observation of stable filaments in 4 and 6 M urea suggests that epidermal keratins K1, K2, and K10/11, which ultimately form the bulk of the protective, nonviable stratum corneum, may comprise filaments that are unusually resistant to denaturation.

Retention of antimony in skin biopsies of leishmaniasis patients after treatment with N-methylglucamine antimoniate

Leishmaniasis patients were treated with N-methylglucamine antimoniate by intravenous injections of 10 or 20 mg of Sb per kilogram of body weight per day for 10 or 20 days. Digests of skin biopsies taken from the site of lesion before and after treatment were analyzed for antimony by instrumental neutron activation (INAA). The detection limit of the assay was 20 ng, and no Sb could be measured in digests of samples (less than 2.45 mg) taken before treatment. Biopsies taken after injections of Sb showed concentrations in the range of 8.32 to 70.68 ng/g skin. We discuss the usefulness of INAA in the study of Sb in small samples of tissues.

High levels of c-fos proto-oncogene expression in normal human adult skin

The proto-oncogene c-fos is thought to play an important role in the modulation of cell growth and differentiation. In normal tissues that have been studied to date, c-fos expression has been found to be regulated in a tissue-specific manner. Actually, little is known about its expression in normal human adult skin (NHAS). Moreover, the epidermis is a useful tissue to study the role of cellular oncogenes because keratinocytes can be observed simultaneously in their proliferative as well as differentiated state. We studied c-fos expression in NHAS using different molecular approaches which permit us to characterize and localize c-fos products within the epidermis, specifically, at the RNA level by Northern blot and in situ hybridization, and at the protein level by immunofluorescence and Western blotting. Here, we show that both c-fos mRNA and protein are present at high levels in NHAS. These results contrast with the low level of c-fos expression reported for most human adult tissues. Furthermore, c-fos expression is visible throughout the epidermal layers indicating that it is not restricted to proliferating basal cells. The epidermis, therefore, represents the first human adult tissue where c-fos is expressed at high levels in vivo and provides an interesting model to further elucidate the role of this proto-oncogene in normal and pathologic conditions.

Remarkable elevation of leukotriene B4 in rat skin after induction of UV photodermatitis

Leukotriene B4 in the skin was remarkably elevated in the rat, but not in the guinea pig or the mouse 48 h after UV-B irradiation. These results were consistent with interspecies difference of PMN infiltration caused by UV-B irradiation. LTB4 in the rat skin was determined by both high-performance liquid chromatography and radioimmunoassay. LTB4 in the rat skin started to increase 24 h after irradiation and became about 65-fold higher in the irradiated site than in the nonirradiated site at the end of 48 h. This elevation was strongly inhibited by topical application of two 5-lipoxygenase inhibitors, AA-861 and piriprost, although the inflammatory reaction or infiltration of polymorphonuclear leukocytes was not much improved.

Expression of catfish amino acid taste receptors in Xenopus oocytes

We demonstrate that poly (A+)RNA isolated from catfish barbels directs the expression of functional amino acid taste receptors in the Xenopus oocyte. The activity of these receptors is monitored in ovo by the two electrode voltage clamp technique. Specific conductance changes recorded in response to amino acid stimulation are analogous to those recorded electrophysiologically from intact catfish barbels. These responses exhibit specificity, reproducibility, rapid onset and termination, and desensitization to repetitive stimulation. A functional assay system that encompasses the full complement of transduction events from the ligand-receptor interaction to subsequent conductance changes is necessary to identify molecular components responsible for these events. Our results demonstrate that the Xenopus oocyte can be used to characterize and identify clones coding for amino acid taste receptors analogous to its use in studying receptor molecules for other neuroactive compounds.