Accessory cell ability of Langerhans cells for superantigen is resistant to ultraviolet-B light

We examined the effects of ultraviolet-B (UVB) irradiation on the accessory cell ability of Langerhans cells (LC) to induce a T-cell response to a superantigen, staphylococcal enterotoxin B (SEB). The ability of LC-enriched epidermal cells (LC-EC) to evoke a T-cell response to SEB was retained at the doses of UVB (up to 40 mJ/cm2) that profoundly affected the antigen-presenting function of LC-EC for a hapten, trinitrophenyl (TNP), and a protein antigen, conalbumin. Thus, the LC accessory function for superantigens is more resistant to UVB irradiation than that for ordinary antigens. This UVB resistance is presumably due to no requirement of antigen processing for superantigens as chemically fixed or chloroquine-treated LC-EC still retained their ability to induce T-cell responses to SEB. Higher doses of UVB (more than 60 mJ/cm2) reduced the accessory cell ability of LC-EC for SEB up to 50% of control. The addition of monoclonal antibodies against adhesion molecules between LC and T cells to the culture resulted in a substantial suppression of the T-cell response to SEB induced by nonirradiated LC-EC, while the UVB-irradiated LC-EC-induced T-cell response was not significantly blocked with these monoclonal antibodies. This suggested that the reduction of LC ability for superantigen by high doses of UVB is at least partly due to the impairment of adhesion molecules on LC by UVB irradiation.

Keratinocyte differentiation is induced by cell-permeant ceramides and its proliferation is promoted by sphingosine

Ceramide and sphingosine have been suggested to be intracellular modulators of cell growth and differentiation. The effects of these sphingolipids on the growth and differentiation of keratinocytes were examined using cultured human keratinocytes (the squamous cell carcinoma cell line, DJM-1). The synthetic short-chain cell-permeant analogues of ceramides, N-acetylsphingosine, N-hexanoylsphingosine and N-octanoylsphingosine, significantly promoted differentiation as confirmed by upregulation of cornified envelope formation, synthesis of involucrin and increased transglutaminase activity, and inhibited proliferation as shown by a reduction in cell numbers, DNA amount and thymidine incorporation. Generally, these activities were greater the longer the N-acyl carbon chain. On the other hand, sphingosine at an appropriate concentration modestly stimulated the proliferation of cultured cells. Our results suggest the possibility that the growth and differentiation of keratinocytes are at least partially regulated by ceramide and sphingosine.

[Quantitative flow-cytometric analysis of CD34-positive stem cells in peripheral blood stem cell harvests]

The percentage of CD34-positive cells (the CD34-positive rate) in peripheral blood stem cell harvests (PBSCH) was determined using two color flow cytometric methods, i.e., representation in a histogram (the histogram method) and the two-dimensional side scatter-fluorescence representation (the SSC-FL method). For all samples examined, the CD34-positive rate obtained using the histogram method was higher than that obtained using the SSC-FL method. This finding was probably due to the fact that some monocytes non-specifically reacted with anti-CD34 monoclonal antibody, and the histogram method could not distinguish these non-specifically stained cells from CD34-positive precursor cells. On the other hand, the SSC-FL method seemed to yield a more accurate measurement of the percentage of CD34-positive cells in PBSCH samples. Based on this finding, it is recommended that the histogram method, which is currently used at most commercial laboratories, be reviewed in favor of the SSC-FL method when the CD34-positive cell rate of PBSCH is to be determined.

Familial congenital hypopituitarism with central diabetes insipidus

Congenital hypopituitarism (CH) presenting with central diabetes insipidus is typically associated with midline facial deformities or ophthalmological abnormalities. We present three brothers with CH and central diabetes insipidus not associated with any of these predisposing conditions. All three subjects presented with clinical features typical for CH (neonatal hypoglycemia, short stature, protruding forehead, and microgenitalia). All had hypoplastic genitalia indicating in utero gonadotropin deficiency, and all had complete GH deficiency. One represented low levels of thyroid hormones and TSH, indicating central hypothyroidism. Water deprivation examination in two of the brothers demonstrated complete arginine vasopressin deficiency in one and partial deficiency in the other. Magnetic resonance imaging indicated absence of the pituitary stalk, severe hypoplastic anterior pituitary in all three brothers, and absence of any posterior pituitary gland in two of the three. The other sibling had an ectopic posterior pituitary. This first report of familial CH with central diabetes insipidus may represent a previously unknown midline anomaly and provide new insights into the genetic control of pituitary and hypothalamic development.

Facial erythema and pigmentation as an initial manifestation of chronic graft-versus-host disease

Two bone marrow transplant recipients developed chronic graft-versus-host disease, presenting with a mild erythematous, pigmented eruption only on the face three and ten months after transplantation. Histologically, the lesions showed liquefaction degeneration of basal keratinocytes and incontinence of melanin in the upper dermis with a mild infiltrate of T-lymphocytes. These findings suggest that such a facial eruption occasionally may represent an initial manifestation of chronic GVHD.

Evaluation of ultraviolet-A protection by sunscreen agents using a mouse model of contact photoallergy

This study was conducted to investigate in vivo evaluation of protectiveness by sunscreens in the UVA range using a mouse model of contact photoallergy (CPS) to 3,3',4',5-tetrachlorosalicylanilide (TCSA). Mice were sensitized with TCSA painting plus UVA irradiation (TCSA/UVA) on the abdomen and, 5 days later, challenged with TCSA/UVA on the earlobe. Each of four sunscreen agents, benzophenone-3, Parsol 1789, p-aminobenzoic acid, and 2-ethyl-hexyl-p-methoxycinnamate, was applied to the earlobes before irradiation. Their protective efficacy was evaluated in the degree of inhibition of both ear swelling responses and TCSA-epidermal cell photoadduct formation. Two UVA-absorbing sunscreens, benzophenone-3 and Parsol 1789, dramatically inhibited the ear swelling response, while the two UVB-absorbers exhibited a much less suppressive effect. The UVA-absorbing agents functioned via inhibiting the formation of TCSA-epidermal cell photoadducts. This method is thought to be useful for in vivo estimation of UVA protection provided by sunscreens against the exquisite sensitivity involved in photoallergy.

Cutaneous T-cell lymphoma with massive co-infiltration of polyclonal B cells

A 76-year-old man presented with a 3-month history of a cutaneous nodule on the right thigh. The tumour was composed of CD3+, large atypical cells, and CD20+, small normal-appearing cells. Flow cytometry showed that CD20+ cells outnumbered CD3+ cells. By Southern blot hybridization analyses, the malignant cells were shown to be of T-cell origin, because of the presence of rearranged bands for the beta chain of the T-cell receptor, but not for the immunoglobulin heavy chain. This case represents a T-cell lymphoma intermingled with a large number of non-neoplastic B cells.

Disseminated pagetoid reticulosis: need for long-term follow-up

A 54-year-old woman had an erythematous plaque on the left index finger for 2 years. Histologically there was a dense infiltrate of atypical mononuclear cells in the epidermis that produced a pagetoid appearance. A diagnosis of localized pagetoid reticulosis was made. Three years after total removal of the finger lesion, erythematous plaques appeared on her left thigh, followed by the development of similar plaques on the right thigh and lower abdomen. Histologically these skin lesions had the same pagetoid appearance as the plaque on the finger. This suggested development of the disseminated type of pagetoid reticulosis, long after removal of the initial skin lesion.

Different effects between antihypertensive drugs on nephrotic-range proteinuria in renovascular hypertension

A 61-year-old man developed renovascular hypertension characterized by nephrotic-range proteinuria. When he was treated with a calcium channel blocker, glomerular filtration fraction was 0.26 and massive proteinuria ranging from 10 to 15 g/day persisted. An angiotensin-converting enzyme inhibitor markedly reduced the proteinuria to 1-2 g/day with a filtration fraction of 0.20. After the antihypertensive drug was switched to a beta-blocker, the filtration fraction was 0.23 and urinary protein excretion was 3-4 g/day. Blood pressure control was comparable by each drug. These findings suggest a role of intraglomerular hydraulic mechanism in the etiology of massive proteinuria in renovascular hypertension.

Pemphigus associated with metastatic carcinoid

Patients with pemphigus are occasionally associated with neoplasms. We report a case of pemphigus with carcinoid. To our knowledge, this is the first case of coexistence of pemphigus and carcinoid.

A case of bullous systemic lupus erythematosus

We report a case of bullous systemic lupus erythematosus (SLE). The patient suddenly presented with a widespread blistering eruption on the trunk and neck during the course of treatment of SLE. A skin biopsy specimen showed subepidermal blisters, and direct immunofluorescence (IF) revealed deposition of IgA, IgG and IgM at the dermoepidermal junction. Indirect IF showed linear IgG deposition along the base of 1 M NaCl-split skin. Rapid resolution of the blisters occurred following treatment with dapsone 50 mg daily.

Acidic fibroblast growth factor facilitates generation of long-term potentiation in rat hippocampal slices

In the present study, effects of acidic fibroblast growth factor (aFGF, 0.5-2.5 ng/ml) on synaptic transmission were investigated in rat hippocampal slices. Stimulation was applied to Schaffer collateral/commissural afferents and evoked spikes were recorded in CA1 pyramidal cell layer. Continuous perfusion of slices with aFGF slightly decreased the basal amplitude of the spikes and significantly increased the paired-pulse facilitation. When brief tetanic stimulation (7 impulses at 100 Hz) was applied 30 min after the perfusion of aFGF, aFGF-treated slices enhanced the magnitude of short-term potentiation after the tetanus and facilitated the generation of long-term potentiation. aFGF also enhanced post-tetanic potentiation directly after the tetanus. These effects of aFGF were dose-dependent. The enhancement of short-term potentiation and facilitation of the generation of long-term potentiation were not evident when aFGF was applied with or 10 min after the tetanus. The results suggest that aFGF is implicated in modulation of synaptic efficacy and can activate some mechanisms related to the generation of long-term potentiation.

[Extracapsular tumor invasion in renal cell carcinoma: with special reference to limitation of surgical enucleation]

To elucidate the feasibility of surgical enucleation, the incidence of extracapsular tumor invasion in 30 cases of renal cell carcinoma with a diameter less than 5 cm was examined, based on the classification of extracapsular tumor invasion into three patterns, namely microinvasion, nodular invasion, and daughter tumors. Of the 30 cases of renal cell carcinoma, 22 cases (73%) revealed extracapsular tumor invasion. And the incidence of microinvasion, nodular invasion and daughter tumors was 7 cases (23%), 9 cases (30%) and 6 cases (20%), respectively. But the incidence of these three patterns of extracapsular tumor invasion correlated neither with the size of renal cell carcinoma nor with pT classification. There was a tendency for extracapsular tumor invasion to occur near the renal hilar site of the renal cell carcinoma, where the tumor vessels were rich, penetrated and twined around the tumor capsule, resulting in the disruption of the tumor capsule. These three patterns of invasion was located within 1 cm in distance from the tumor capsules in all cases. In conclusion, because of limited radicality achieved by tumor enucleation even in the case of pT1, partial nephrectomy was recommended in the presence of a normal contralateral kidney.

Inhibitory effect of melanin pigment on sensitization and elicitation of murine contact photosensitivity: mechanism of low responsiveness in C57BL/10 background mice

We have shown that murine contact photosensitivity (CPS) to 3,3',4',5-tetrachlorosalicylanilide (TCSA) is genetically controlled mainly by the major histocompatibility complex. The H-2b,d haplotypes are closely associated with high responders, whereas mice with the H-2k are non-responders. Irrespective of their H-2 haplotypes, the C57BL/10 (B10) background strains, including B10, B10.D2, B10.A, and B10.BR, possessing black fur color, were low or nonresponders in CPS to TCSA. In B10 mice, however, high-sensitivity responses were induced when subcutaneous inoculation of epidermal cells (ECs) photomodified in vitro with TCSA was used for both immunization and challenge, suggesting that the epicutaneous route for induction and elicitation is defective in B10 background mice. F1 mice obtained by crossing high-responder BALB/c and low-responder B10 mice, possessing agouti fur color, were non-responders of CPS. The magnitude of CPS in the F2 mice derived from F1 (BALB/c X B10) siblings varied from low to high. When these F2 mice were divided into five groups with regard to fur color, the magnitude of reaction was correlated with the fur color and there was inverse relationship between the magnitude of CPS and the amount of melanin pigment in earlobe ECs. Furthermore, the in vivo formation of TCSA-EC photoadducts was negatively correlated to the melanin amount in earlobes. These observations suggested that the failure in CPS of the B10 background mice stems from inability of in vivo photocoupling of TCSA to ECs, presumably due to absorption of ultraviolet radiation by melanin pigment.

Relationship between serum levels of methylguanidine and glycemic control in IDDM children

OBJECTIVE

To examine the serum levels of methylguanidine in IDDM children and compare them with markers for glycemic control. Reports have indicated that active oxygen, which damages various tissues, increases in diabetes mellitus. The increase of active oxygen is one of the risk factors for diabetic complications. The synthesis of methylguanidine, a metabolic product of guanidine, is mainly regulated by active oxygen.

RESEARCH DESIGN AND METHODS

Forty-eight children with IDDM (mean age 13.3 yr) and 17 age-matched nondiabetic control subjects were studied. Diabetic children were divided into a well-controlled group (HbA1c < 8%, n = 24) and a poorly controlled group (HbA1c > 8%, n = 24). Serum concentrations of methylguanidine were measured by enzymatic assay.

RESULTS

Levels of methylguanidine in the poorly controlled group (1.31 +/- 0.08 microM) were significantly higher than those in both the well-controlled group (0.85 +/- 0.08 microM) and the control group (0.59 +/- 0.11 microM), respectively (P < 0.01). Methylguanidine levels showed a positive correlation with the levels of HbA1c (P < 0.01) or fructosamine (P < 0.01). No significant correlations were noted between methylguanidine levels and age, sex, duration of diabetes, or insulin dose.

CONCLUSIONS

Our data indicate that the levels of methylguanidine in IDDM children might be affected by glycemic control and that the determination of serum methylguanidine levels could be a useful test for evaluating the state of diabetic control.

Newborn rabbit gastric smooth muscle cell culture: EGF and TGF-alpha are potent mitogens

Epidermal growth factor (EGF) and transforming growth factor-alpha (TGF-alpha) are two in a family of growth-promoting peptides for many gastrointestinal epithelia. This study was designed to assess their mitogenic effect on cultured gastric myocytes and to characterize specific EGF receptors on these cells. Single myocytes were isolated from newborn rabbit gastric fundus and placed into tissue culture. The composition of the culture at confluence as assessed by immunostaining with smooth muscle actin-specific monoclonal antibody (CGA7) was > 95% myocytes. To assess the effect of putative growth factors, freshly isolated myocytes were incubated in Dulbecco's modified Eagle's (DME) medium containing 1% fetal bovine serum in the presence or absence of growth factors. After 6 days, cells were incubated in serum-free medium with [3H]thymidine (1 microCi/ml) in the continued presence or absence of growth factors. After 24 h, EGF and TGF-alpha but not insulin-like growth factor I (IGF-I) induced a dose-dependent increase in [3H]thymidine incorporation. Ten nanomolar EGF or TGF-alpha increased [3H]thymidine incorporation more than sixfold over control. EGF was more potent than was TGF-alpha, with apparent median effective dose (ED50) values of 64 +/- 14 pM and 166 +/- 62 pM (p < 0.05), respectively. EGF bound to cultured myocytes with Kd = 7.6 +/- 1.8 nM and Bmax = 27 +/- 11 pmol/mg DNA or 440,000 receptors/cell. TGF-alpha competed for binding at these receptors. Although IGF-I did not stimulate thymidine incorporation, specific high-affinity receptors for IGF-I were detected on gastric myocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Dose-dependent differences in the profile of mutations induced by (+)-7R,8S-dihydroxy-9S,10R-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene in the coding region of the hypoxanthine (guanine) phosphoribosyltransferase gene in Chinese hamster V-79 cells

Chinese hamster V-79 cells were exposed to a high dose (0.30-0.48 microM; 32% cell survival), an intermediate dose (0.04-0.10 microM; 100% cell survival) or a low dose (0.01-0.02 microM; 97% cell survival) of (+)-7R,8S-dihydroxy-9S,10R-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene [(+)-BPDE] which is the ultimate carcinogenic metabolite of benzo(a)pyrene. The mutation frequency for cells treated with dimethyl sulfoxide vehicle or with low, intermediate or high dose of (+)-BPDE were 1, 10, 52 or 514 8-azaguanine-resistant colonies/10(5) survivors, respectively. Independent 8-azaguanine-resistant clones were isolated, and complementary DNAs were prepared by reverse transcription. The coding region of the hypoxanthine (guanine) phosphoribosyltransferase (HPRT) gene was amplified by the polymerase chain reaction and sequenced. Altogether, 368 (+)-BPDE-induced mutant clones were examined. At all doses, base substitutions were the most prevalent mutations observed (about 72% of the mutant clones), followed by exon deletions (about 26% of the mutant clones) and frame-shift mutations (about 6% of the mutant clones). At the high cytotoxic dose, 7 of 120 base substitutions occurred at AT base pairs (6%) and 113 at GC base pairs (94%). At the intermediate noncytotoxic dose, 20 of 82 base substitutions occurred at AT base pairs (24%) and 62 at GC base pairs (76%). At the low noncytotoxic dose, 27 of 76 base substitutions were at AT base pairs (36%) and 49 were at GC base pairs (64%). The results indicated that decreasing the dose of (+)-BPDE decreased the proportion of mutations at GC base pairs and increased the proportion of mutations at AT base pairs. At the dose of (+)-BPDE was decreased, there was a dose-dependent decrease in the proportion of GC-->TA transversions (from 69% to 42% of the base substitutions) and a dose-dependent increase in the proportion of AT-->CG transversions (from 1% to 25% of the base substitutions). The data also indicated dose-dependent differences in (+)-BPDE-induced exon deletions and hot spots for base substitutions at GC and AT base pairs. Although more than 99% of the (+)-BPDE-induced mutations at guanine occurred on the nontranscribed strand of DNA, (+)-BPDE-induced mutations at adenine occurred on both the transcribed and nontranscribed strands. The ratio of mutations at adenine on the transcribed strand to mutations at adenine on the nontranscribed strand was 35:19 in (+)-BPDE-treated V-79 cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Enhancement of ascites on MRI following intravenous administration of Gd-DTPA

OBJECTIVE

The enhancement of ascites following intravenous administration of Gd-DTPA on MRI was investigated.

MATERIALS AND METHODS

Magnetic resonance imaging was performed in 20 patients with ascites (8 peritoneal carcinomatosis, 2 tuberculous peritonitis, 8 liver cirrhosis, 1 nephrotic syndrome, 1 peritoneal adhesion), and T1-weighted SE images were obtained before and 15-20 min following intravenous administration of Gd-DTPA (0.1 mmol/kg).

RESULTS

There were 10 exudative ascites and 10 transudative ascites. Eight of 10 exudative ascites showed enhancement, in contrast to none of 10 transudative ascites. The precontrast signal intensity ratios (SIRs) of exudative ascites were significantly higher (p < 0.05) than those of transudative ascites, and the postcontrast SIRs of exudative ascites were significantly higher (p < 0.01) than those of transudative ascites. This difference was thought to be caused by increased peritoneal permeability and higher protein concentration in the cases with exudative ascites in this study.

CONCLUSION

It is concluded that enhancement of ascites on MRI obtained 15-20 min after intravenous administration of Gd-DTPA is not an uncommon finding in exudative ascites (especially associated with peritoneal carcinomatosis).

Transfer of autoimmune diabetes from diabetic NOD mice to NOD athymic nude mice: the roles of T cell subsets in the pathogenesis

The NOD mouse, which spontaneously develops insulitis and overt diabetes, is a model of autoimmune type I diabetes mellitus. To analyze of the roles of CD4+ and CD8+ T cells in the pathogenesis of this mouse, we have been doing a series of studies on the induction of insulitis and diabetes in NOD athymic nude mice by means of T cell transfer. To complement our previous study dealing with the induction of insulitis and cyclophosphamide-induced diabetes in recipients that had been reconstituted with each T cell subset derived from the nondiabetic mice, the present study was conducted to observe the transfer of spontaneous diabetes by injecting T cells harvested from diabetic mice. Any possible in vivo increase in the contaminating T cell subset was prevented by injecting the antibody homologous to it. Transfer of untreated or complement-treated splenic lymphocytes of diabetic mice containing both T cell subsets induced spontaneous diabetes 30 to 58 days after the cell transfer as well as insulitis, while spleen cells from nondiabetic mice rarely produced diabetes. On the other hand, transfer of either CD4+ cell-depleted or CD8+ cell-depleted splenic lymphocytes of diabetic mice did not cause diabetes at least up to 60 days after the cell transfer. Also, transfer of only the CD4+ T cell-depleted fraction did not cause insulitis. In contrast, transfer of only the CD8+ T cell-depleted fraction induced insulitis in all the recipients. However, insulitis was less potent in this group of mice than in the diabetic recipients given both subsets: only a low insulitis score was obtained and a number of beta-cells remained alive despite the insulitis in mice given the CD8+ T cell-depleted fraction, whereas islet damage was very severe and insulin-secreting beta-cells were no longer detected in the diabetic mice. Thus, the present results agree with the previous ones concerning transfer of diabetes, with the aid of cyclophosphamide treatment, by T cells of nondiabetic mouse origin. Consideration of our results together with earlier findings led to the conclusion that CD4+ T cells are primarily responsible for insulitis and that CD8+ T cells migrate into islets and are differentiated into mature killer cells against beta-cells with the aid of CD4+ T cells in both spontaneous and cyclophosphamide-induced diabetes.

Sequence specificity in the interaction of the four stereoisomeric benzo[c]phenanthrene dihydrodiol epoxides with the supF gene

The shuttle vector pS189 was treated with each of the four configurational isomers of benzo[c]phenanthrene 3,4-dihydrodiol 1,2-epoxide, and the modified DNA was used as a template in a polymerase arrest assay examining the supF gene. Sites at which polymerase (Sequenase, version 2.0) progress along the template was blocked were presumed to be at or near sites of adduct formation. The polymerase arrest sites were compared with recently reported mutation hotspots induced by these agents in this gene (Bigger et al., Proc. Natl. Acad. Sci. USA, 89: 368-372, 1992). For 31 of 32 mutation hotspots, a polymerase arrest band was present at or 1 or 2 nucleotides 3'- to that site, indicating that adduct formation tended to be associated with mutation hotspots. However, the arrest bands near mutation hotspots were not particularly prominent in all cases, and there were many sites of substantial polymerase arrest that were not in the vicinity of mutation hotspots. Thus, factors in addition to chemical selectivity must play key roles in determining sites of mutation.

A new point mutation in the deoxyribonucleic acid-binding domain of the vitamin D receptor in a kindred with hereditary 1,25-dihydroxyvitamin D-resistant rickets

Hereditary 1,25-dihydroxyvitamin D [1,25-(OH)2D]-resistant rickets (HVDRR) is a rare disorder characterized by rickets, alopecia, hypocalcemia, secondary hyperparathyroidism, and normal or elevated serum 1,25-dihydroxyvitamin D levels. We describe a patient with typical clinical characteristics of HVDRR, except that elevated levels of serum phosphorus were present coincident with increased levels of serum intact PTH. The patient was treated with high dose calcium infusion after an ineffective treatment with 1 alpha-hydroxyvitamin D3; serum calcium and phosphorus as well as intact PTH and alkaline phosphatase levels were normalized. Evaluation of phytohemagglutinin-activated lymphocytes derived from this patient revealed that 1,25-(OH)2D3 was unable to inhibit thymidine incooperation, a result that contrasts with the capacity of 1,25-(OH)2D3 to inhibit uptake into normal activated lymphocytes. 1,25-(OH)2D3 did not induce human osteocalcin promoter activity after transfection of this DNA linked to a reporter gene into patient cells. Cointroduction of a human vitamin D receptor (VDR) cDNA expression vector with the reporter plasmid, however, restored the hormone response. Evaluation of extracts from the patient cells for VDR DNA binding revealed a defect in DNA binding. Analysis of genomic DNA from the patient's cells by PCR confirmed the presence of a point mutation in exon 2 of the VDR. This exon directs synthesis of a portion of the DNA-binding domain of the receptor. We conclude that the genetic basis for 1,25-(OH)2D3 resistance in this kindred with VDR-positive HVDRR is due to a single base mutation in the VDR that leads to production of a receptor unable to interact appropriately with DNA.