Localization of three types of the inositol 1,4,5-trisphosphate receptor/Ca(2+) channel in the secretory granules and coupling with the Ca(2+) storage proteins chromogranins A and B

Although the role of secretory granules as the inositol 1,4,5-trisphosphate (IP(3))-sensitive intracellular Ca(2+) store and the presence of the IP(3) receptor (IP(3)R)/Ca(2+) channel on the secretory granule membrane have been established, the identity of the IP(3)R types present in the secretory granules is not known. We have therefore investigated the presence of different types of IP(3)R in the secretory granules of bovine adrenal medullary chromaffin cells using immunogold electron microscopy and found the existence of all three types of IP(3)R in the secretory granules. To determine whether these IP(3)Rs interact with CGA and CGB, each IP(3)R isoform was co-transfected with CGA or CGB into NIH3T3 or COS-7 cells, and the expressed IP(3)R isoform and CGA or CGB were co-immunoprecipitated. From these studies it was shown that all three types of IP(3)R form complexes with CGA and CGB in the cells. To further confirm whether the IP(3)R isoforms and CGA and CGB form a complex in the secretory granules the potential interaction between all three isoforms of IP(3)R and CGA and CGB was tested by co-immunoprecipitation experiments of the mixture of secretory granule lysates and the granule membrane proteins. The three isoforms of IP(3)R were shown to form complexes with CGA and CGB, indicating the complex formation between the three isoforms of IP(3)R and CGA and CGB in the secretory granules. Moreover, the pH-dependent Ca(2+) binding property of CGB was also studied using purified recombinant CGB, and it was shown that CGB bound 93 mol of Ca(2+)/mol with a dissociation constant (K(d)) of 1.5 mm at pH 5.5 but virtually no Ca(2+) at pH 7.5. The high capacity, low affinity Ca(2+)-binding property of CGB at pH 5.5 is comparable with that of CGA and is in line with its role as a Ca(2+) storage protein in the secretory granules.

Anticancer effect of a lentiviral vector capable of expressing HIV-1 Vpr

A lentiviral vector capable of expressing the HIV-1 vpr gene (Vpr lentiviral vector) was constructed, and its in vivo anticancer effect was determined against cutaneous tumors derived from the AT-84 oral cancer cells in immunocompetent mice. A single intratumoral injection of the Vpr lentiviral vector not only significantly reduced the primary tumor volume but also completely regressed tumors in >40% of animals. More interestingly, the mice of which the primary tumors were completely regressed by the Vpr lentiviral vector were additionally protected from a secondary challenge of AT-84 cells. These data suggest that the Vpr lentiviral vector elicits its anticancer activity in part by the activation of the immune system. The above suggestion is additionally supported by the failure of the lentiviral vector to demonstrate anticancer activity in immunocompromised nude or SCID mice. The Vpr lentiviral vector offers a powerful new strategy for cancer gene therapy and may be useful for the control of solid tumors, such as human oral squamous cell carcinomas.

Elevated expression of hTERT is associated with dysplastic cell transformation during human oral carcinogenesis in situ

PURPOSE

Telomerase is a ribonucleoprotein complex composed of the catalytic protein subunit (human telomerase reverse transcriptase or hTERT) and the RNA template. This enzyme activity is a necessary and rate-limiting step of cellular immortalization and could provide a unique marker of aberrant cells, which may selectively be targeted. The current study was undertaken to quantitatively determine the degree of telomerase activation during multistage oral carcinogenesis using paraffin-embedded tissue samples.

EXPERIMENTAL DESIGN

hTERT expression level was quantitatively compared between normal and cancerous oral tissues by real-time reverse-transcription-PCR (RT-PCR). Also, the presence of hTERT transcript in individual cells was surveyed in the biopsy specimens with varying degrees of histopathology by in situ RT-PCR.

RESULTS

Low level of hTERT amplification was detected by real-time RT-PCR in most (11/13) normal human oral mucosa. hTERT expression was also detected in the majority (11/12) of squamous cell carcinoma tissues, and the level was significantly (P < 0.05) elevated, on the average, by a factor >6.9. By in situ RT-PCR, hTERT expression was not noted in normal epithelium (0/10) nor in mild dysplasia (0/7) but was detected in moderate dysplasia (4/5) and in those tissues with a higher grade of histopathology: severe dysplasia (3/3) and invasive carcinoma (4/4).

CONCLUSIONS

These results indicate that enhanced expression of telomerase activity occurs early during human oral carcinogenesis and support the critical role of telomerase in the development of human oral cancer.

c-Myc and Sp1/3 are required for transactivation of hamster telomerase catalytic subunit gene promoter

The hamster and human TERT promoters share common critical protein binding sites, such as the GC-box or E-box, which is known to be a binding site for Sp1/Sp3 transcriptional factors and c-Myc, respectively. Our previous data demonstrated that Sp1/Sp3 synergistically transactivate the hamster TERT (hamTERT) promoter. In this study, we determined the role of c-Myc in the regulation of hamTERT, and analyzed the relative significance of GC-boxes and the E-box for transcriptional activation of hamster TERT. Wild-type, mutated E-box or mutated GC-box hamTERT core promoter reporter was introduced into 293T cells in combination with murine or human Myc expression vectors. The promoter activity was determined using the luciferase assay, and the transfection efficiency was normalized with CAT activity. The electrophoretic mobility shift assay (EMSA) was done to prove the nuclear protein binding activity of the GC-box (region II) or E-box. Overexpression of murine or human Myc transactivated hamTERT core promoter activity. Inversion mutation in the E-box or substitution mutation in the GC-boxes abrogated endogenous or Myc induced hamTERT transactivation. Region II is the single most important Sp1/3 binding site in transcriptional activation, and multiple combined mutations in the GC-boxes abolished the hamTERT promoter activity. These results indicate that c-Myc and Sp1/3 are the major regulatory determinants of the hamTERT transcriptional activation. The mechanism of TERT gene activation during immortalization and carcinogenesis may be conserved among species.

Changes in external ear resonance after 3 types of surgery in the patients with chronic otitis media

OBJECTIVE

This study was designed to identify the external ear resonance characteristics of patients with tympanic membrane perforation and to investigate subsequent changes in external ear resonance, depending on the length of the postoperative period and which of 3 different types of operation was performed: tympanoplasty with canal wall-up mastoidectomy, epitympanoplasty, and canal wall-down mastoidectomy.

STUDY DESIGN AND SETTING

A total of 227 ears of 188 patients and 96 control ears comprised the study. We measured the gain and frequency of the first peak of external ear resonance with a real ear analyzer.

RESULTS

Gain and frequency of the first peak recorded in the preoperative group did not differ from those of the control group. However, negative peaks appeared around 1 to 1.5 kHz in half of these ears. The gain increased markedly in all 3 postoperative groups. The canal wall-down mastoidectomy and epitympanoplasty groups showed significantly lower frequencies compared with the tympanoplasty with canal wall-up mastoidectomy and control groups, but there was no difference between them. The increased gain diminished over time, but the peak gain did not equalize with that of the controls, even after 15 months.

CONCLUSIONS

Additional gain should be considered of around 1 to 1.5 kHz for hearing aid users with tympanic membrane perforation. Postoperative changes in external ear resonance should be expected in patients with chronic otitis media, suggesting that fine readjustments of the hearing aid may be necessary.

A case of glomerulonephritis in association with pyogenic liver abscess

Glomerulonephritis associated with visceral abscess is being increasingly recognized. The association of glomerulonephritis with visceral suppuration in the absence of endocarditis was first described by Whitworth and associates. Abscesses were most frequently located in the respiratory tract but have been reported at numerous other sites, including appendix, uterus, aorto-femoral bypass graft and cutaneous wound. This report documents the apparently rare occurrence of glomerulonephritis with acute renal failure in association with pyogenic liver abscess. The need for awareness of glomerulonephritis as a cause of acute renal failure in pyogenic liver abscess is highlighted.

Decussation patterns of the platysma in Koreans

The importance of the platysma muscle in plastic surgery is well known. During surgery, we have observed that the platysmal fibres do not merely decussate and interlace from each side but that sometimes one side of the muscle overlaps and covers the other side. The aim of this study was to clarify the precise anatomical variations in the decussation and overlapping patterns of the platysma muscle in 70 Korean cadavers. We defined three groups (types I--III) and four patterns (types A--D) according to the length of decussation and the pattern of overlapping, respectively. In 60 specimens (85.7%) we observed decussation and in 10 (14.3%) we did not. In type I there was 0--20 mm of decussating fibres below the mandibular border (43% of specimens). In type II, the decussation of fibres extended over more than 20 mm (43% of specimens). Type III had no decussation (14% of specimens). The proportions of type A (interlacing pattern), type B (right dominant), type C (left dominant) and type D (no decussation) were 41%, 29%, 16% and 14%, respectively. In 45% of the specimens, one side of the platysma covered and overlapped the other side. This is relevant to the removal of the subplatysmal fat in corset platysmaplasty, submental Z-plasty and vertical myectomy of the platysma muscle.

Ester and hydroxamate analogues of methionyl and isoleucyl adenylates as inhibitors of methionyl-tRNA and isoleucyl-tRNA synthetases

The structure activity relationship on a series of ester and hydroxamate analogues of methionyl and isoleucyl adenylate has been investigated through introducing linkers between the 1'-position of ribose and adenine surrogates as methionyl-tRNA, and isoleucyl-tRNA synthetase inhibitors, respectively. The results indicate that ester analogue 23 was found to be a potent inhibitor of Escherichia coli methionyl-tRNA synthetase, and its interaction with the active site was proposed by a molecular modeling study.

In vitro replication and differentiation of normal human oral keratinocytes

The replication kinetics and cytological changes of normal human oral keratinocytes (NHOK) isolated from the basal surface of oral epithelial sheet and cultured as dispersed cells in low (0.15 mM) Ca(2+) medium without serum were analyzed. Replicating NHOK were quantitated by cell count and identified by [(3)H]thymidine uptake. Cell morphology was analyzed by phase contrast and transmission electron microscopy, and by cytochemical staining for endogenous beta-galactosidase (beta-gal) activity, involucrin, and cytokeratin types 1 and 10 (K1/K10). Primary NHOK obtained from 15 different donors whose ages ranged from 21 to 62 years consistently showed three distinct phases of replication, i.e., exponential, senescing, and senescent, which were independent of the donors' age. Initially, the cells replicated exponentially for a period of 20 days with a doubling time of 26.6 +/- 3.5 h. They then gradually entered replication arrest over a period of 18 days. The cells underwent a maximum of 22.1 +/- 2.8 population doublings. The onset of gradual replication arrest coincided with an increase in the fraction of cells, which stopped DNA synthesis within a maximum of 48 h and which stained for beta-gal. The fraction of terminally differentiated cells stained for K1/K10 did not increase until nearly all the cells had stopped replicating (senescent phase) and maximal beta-gal staining had been reached. Subsequently, the percentage of beta-gal stained cells actually decreased while the percentage of those stained for K1/K10 increased to a maximum of 80-90% within 2-3 weeks. Exposure of exponentially replicating NHOK to 5-aza-2'-deoxycytidine (5-aza CdR) inhibited DNA replication within 18-48 h and induced terminal differentiation 6 days later. In contrast, exposure of these cells to 1.5 mM Ca(2+) induced expression of involucrin and K1/K10 within 48 h without inhibiting DNA synthesis. Thus, replication arrest preceded differentiation in NHOK serially subcultured in vitro; however, differentiation could be induced without replication arrest.

Coupling of the inositol 1,4,5-trisphosphate receptor and chromogranins A and B in secretory granules

The secretory granules of neuroendocrine cells which contain large amounts of Ca(2+) and chromogranins have been demonstrated to release Ca(2+) in response to inositol 1,4,5-trisphosphate (IP(3)). Moreover, chromogranin A (CGA) has been shown to interact with several secretory granule membrane proteins, including the IP(3) receptor (IP(3)R). To determine whether the IP(3)Rs interact directly with chromogranins A and B (CGB), two major proteins of the secretory granules, we have used purified IP(3)R from bovine cerebellum in the interaction study with CGA and CGB, and have shown that chromogranins A and B directly interact with the IP(3)R at the intravesicular pH 5.5. Immunogold cytochemical study using the IP(3)R and CGA antibodies indicated that IP(3)R-labeled gold particles were localized in the periphery of the secretory granules, indicating the presence of the IP(3)Rs on the secretory granule membrane. To determine whether the IP(3)R and chromogranins A and B are physically linked in the cells, bovine type 1 IP(3)R (IP(3)R-1) and CGA or CGB are co-transfected into COS-7 cells and co-immunoprecipitation was carried out. Immunoprecipitation of the cell extracts demonstrated the presence of CGA-IP(3)R-1 and CGB-IP(3)R-1 complexes, respectively, indicating the complex formation between the IP(3)R and chromogranins A and B in native state.

Synthesis of the quinoline-linked triazolopyrimidine analogues and their interactions with the recombinant tobacco acetolactate synthase

Acetolactate synthase (ALS) is the first common enzyme in the biosynthesis of L-leucine, L-isoleucine, and L-valine. Triazolopyrimidine sulfonamide (TP) is a mixed-type inhibitor of ALS with respect to both pyruvate and thiamine pyrophosphate. In this study, we synthesized new substituted quinoline-linked TP analogues and several TP analogues which contained either unsubstituted aminoquinolines or amino isoquinolines. In addition, we examined the interactions of both the wild-type and the sulfonylurea-resistant recombinant tobacco ALS enzymes in a highly pure and active form with the quinoline-linked TP analogues, respectively. The wild-type tobacco ALS was extremely sensitive to inhibition by the quinoline-linked TP analogues. In contrast, the mutant tobacco ALS was insensitive to both the quinoline-linked triazolopyrimidine and the sulfonylurea herbicides. The results indicate that the ability of the quinoline-linked TP analogues to inhibit ALS is highly sensitive to substitution at the ortho position (C-7) and to the position of the ring nitrogen around the sulfonamide functionality (C-8).

Methionyl adenylate analogues as inhibitors of methionyl-tRNA synthetase

Four stable analogues of methionyl adenylate (3-6) were designed as inhibitors of methionyl-tRNA synthetase and synthesized from 2',3'-isopropylideneadenosine. They strongly inhibited aminoacylation activity of methionyl-tRNA synthetases isolated from Escherichia coli, Mycobacterium tuberculosis, Saccharomyces cerevisiae and human. Among the microorganisms tested, however, these chemicals showed the growth inhibition effect only on E. coli.

Methionine analogues as inhibitors of methionyl-tRNA synthetase

A series of methionine analogues have been synthesized as inhibitors of methionyl-tRNA synthetase and evaluated for their inhibitory activities of E. coli methionyl-tRNA synthetase and bacterial growth. Among them, L-methionine hydroxamate 20 has proved to be the best inhibitor of the enzyme with Ki = 19 microM and showed a growth inhibition against E.coli JM 109, P. vulganis 6059 and C. freundii 8090.

Coordinated expression of defense-related genes by TMV infection or salicylic acid treatment in tobacco

To understand the coordinated functions of the different classes of defense-related genes expressed in plant disease resistance, the expression patterns of pathogenesis related (PR) protein genes and genes involved in antioxidation and the production of secondary metabolites were examined. The expression patterns of the respective defense-related genes were monitored following TMV infection or salicylic acid treatment. Northern blot analyses showed that PR genes such as PR-1, beta-1,3-glucanase and chitinase were strongly induced in tobacco leaves upon TMV infection or salicylic acid treatment. 3-Hydroxy-3-methylglutaryl CoA reductase (HMGR) and phenylalanine ammonialyase (PAL), involved in isoprenoid and phenylpropanoid biosynthesis, respectively, were mildly induced at the late stage of normal hypersensitive response (HR) or after salicylic acid treatment when compared with the PR-gene expressions. However, in acute HR, they were strongly expressed at the early stage. Interestingly, the expression of the antioxidative genes, anionic peroxidase and ascorbate peroxidase, were inversely expressed following TMV infection and salicylic acid treatment. Differential expression of 3 groups of genes involved in plant defense responses are discussed in relation to different signal transduction pathways.

Immortalization of human oral keratinocytes is associated with elevation of telomerase activity and shortening of telomere length

Telomerase is a ribonucleoprotein complex that synthesizes TTAGGG repeat sequences at the ends of mammalian chromosomes. Its activity is found in most cancer cells and few rare normal somatic cells. To investigate whether telomerase activity and telomere length of normal human oral keratinocytes (NHOK) are altered by <high risk> human papillomaviruses (HPV), we transfected primary NHOK with type 16 HPV (HPV-16) genome and determined the activity of telomerase. HPV transfection extended the life span of NHOK and eventually induced immortalization of cells. Moderate telomerase activity was consistently observed in rapidly proliferating NHOK, and activity was not changed in HPV-16 transfected cells with extended life span. However, the activity was sharply increased when cells passed the crisis stage. Telomere length, which remained constant at approximately 6.8 kb during serial passages of NHOK, progressively shortened in HPV DNA transfected cells during the period of extended life span and continued until crisis, after which it stabilized at approximately 5 kb. These results demonstrate that immortalization of NHOK with HPV-16 DNA is associated with the activation of telomerase.

Replicative senescence of normal human oral keratinocytes is associated with the loss of telomerase activity without shortening of telomeres

Telomerase activity was analyzed in 7 different cultures of secondary normal human oral keratinocytes (NHOKs), 1 normal human oral epithelial tissue specimen, 1 immortalized human oral keratinocyte (HOK) cell line, and 10 human oral cancer cell lines using the PCR-based telomeric repeat amplification protocol assay. Telomerase activity was found in all tested cells and tissue, but the activity in NHOKs and epithelial tissue was lower than that in other tested cell lines. Inasmuch as continued subculture of NHOKs results in replicative senescence, we investigated the association between telomerase activity and replicative senescence by evaluating the enzyme activity in NHOK cultures with different population doubling levels. Three different NHOK cultures were independently subcultured until these cells reached the postmitotic stage. Unlike in fibroblasts derived from the human oral cavity, significant telomerase activity was detected in rapidly proliferating NHOKs, and telomerase activity was barely detectable in the keratinocytes near and at senescence. However, the terminal restriction fragment consisting of telomeric DNA was found to be constantly maintained at approximately 6.0 kilobases in NHOKs without any detectable shortening of telomeres by subcultures. Intracellular p53 and p21WAF1/CIP1 protein levels in NHOKs were gradually and significantly diminished by the passage of cells. These data indicate that actively proliferating NHOKs contain telomerase activity and that replicative senescence of NHOKs is associated with the loss of telomerase activity without shortening of telomeres. However, replicative senescence of NHOKs is apparently not linked to an accumulation of wild-type p53 and/or p21WAF1/CIP1 proteins in these cells.

Soluble overexpression in Escherichia coli, and purification and characterization of wild-type recombinant tobacco acetolactate synthase

Acetolactate synthase (ALS) is the first common enzyme in the biosynthesis of L-leucine, L-isoleucine, and L-valine. The wild-type ALS gene from Nicotiana tabacum was cloned into the bacterial expression vector pGEX-2T. The resulting recombinant plasmid pGEX-ALS2 was used to transform Escherichia coli strain XL1-Blue, and the wild-type tobacco ALS (wALS) was expressed in the bacteria as a protein fused with glutathione S-transferase (GST). The fusion product GST-wALS was purified in a single step on a glutathione-Sepharose column. The purified GST-wALS was sensitive to a sulfonylurea herbicide, and was lost its sensitivity to end products, L-valine, L-leucine and L-isoleucine. These results suggest that the purified recombinant tobacco ALS was functionally active, and that the sulfonylureas may not bind to the feedback regulatory site on the plant ALS.

Purification and Characterization of Two Xylanases from Alkalophilic Cephalosporium sp. Strain RYM-202

Two different xylanases, CX-I and CX-II, from an alkalophilic fungus, Cephalosporium sp. strain RYM-202, have been purified to homogeneity. The enzymes had similar pH (7.5 to 8.0) and temperature (50(deg)C) optima and were stable over a wide pH range of 5.5 to 12.0. Both enzymes were shown to be cellulase-free endoxylanases with transglycosidation activity.

Aspergillus sinusitis: clinical aspects and treatment outcomes

Seventy-two cases of Aspergillus sinusitis were analyzed during a period of 14 years from January 1980 through October 1993. There were 60 cases of primary type and 12 cases of secondary type. The maxillary and ethmoid sinuses were most commonly affected in both primary and secondary types. The sphenoid sinus was commonly involved in secondary type. Fourteen (23%) cases of primary type and 4 (33%) cases of secondary type demonstrated sinus wall destruction on computed tomography or magnetic resonance images. Seventy percent of primary type and all cases of secondary type showed focal or diffuse areas of increased attenuation in the soft tissue mass on computed tomography scans. Sixteen cases assessed by magnetic resonance imaging showed decreased signal intensities on T1-weighted images and markedly reduced signal intensities on T2-weighted images. Fifty-nine (98%) of 60 cases of primary type were noninvasive, and 1 was invasive. In secondary type, 10 (83%) of 12 patients had noninvasive disease. The most common coexisting disease in secondary aspergillosis was diabetes mellitus. Thickened mucosa with necrotic brownish green material, which was the most common finding in both types, was found in 33 patients with primary type and in 5 with secondary type. Surgery was performed in most cases, among which 4 patients received chemotherapy after surgery with amphotericin B with or without flucytosine. All patients were cured without recurrence during a mean follow-up period of 13 months.

Survey of knowledge, attitudes and practices for tuberculosis among general practitioners

SETTING

Representative sample survey of knowledge, attitudes and practices (KAP) for tuberculosis among private general practitioners (GPs) in 1993 in Korea,

OBJECTIVE

To investigate the KAP of general practitioners on the prevention and treatment of tuberculosis.

DESIGN

Questionnaire surveys were performed for 923 private general practitioners through 29 health centres.

RESULTS

49% of GPs considered that the Korean tuberculosis situation is not serious. 54% were worried about infection from patients. 47% answered that BCG vaccination causes untoward reactions with no or limited effectiveness. 47% considered the National Tuberculosis Programme (NTP) unfavourably. Over 50% did not consider sputum examination essential in case finding/diagnosis, and 75% in monitoring of treatment response. For initial treatment of active tuberculosis, only 11% were prescribing the current Korean NTP's six-month standard regimen. 73% were giving currently non-recommendable regimens, and 16% unacceptably bad regimens. However, this situation could be improved, as 80% of GPs expressed the wish to acquire knowledge.

CONCLUSION

Many misunderstandings were found in the field of transmission, BCG vaccination and the performance of the NTP; sputum examinations were considerably neglected in case finding/diagnosis and treatment monitoring. As for treatment, 89% were giving either non-recommendable regimens or bad regimens.

Effects of adenotonsillar hypertrophy on snoring in children

A prospective study was performed to evaluate the effects of adenotonsillar hypertrophy on snoring in children. Thirty male patients were grouped with respect to the severity of snoring and were evaluated in terms of the noise level of the snoring sound, the lowest arterial oxygen saturation, degree of palatine tonsillar hypertrophy, body mass index and cephalometric findings that included the adenoidal-nasopharyngeal ratio, the angle between the lines sella turcica/nasion and most posterior point of anterior maxilla/nasion, the angle between the lines sella turcica/nasion and most posterior point of anterior mandible/nasion, the posterior airway space, the distance from the sella to the nasion, lower face height and the distance from the basion to the posterior nasal spine. The noise level of the snoring sound, the lowest arterial oxygen saturation and the adenoidal-nasopharyngeal ratio showed a significant correlation with the severity of snoring, but the degree of palatine tonsillar hypertrophy and the body mass index failed to disclose any significant relationship.

Cholesterol biosynthesis from lanosterol: regulation and purification of rat hepatic sterol 8-isomerase

The membrane bound sterol-8-isomerase (isomerase) catalyzes the anaerobic conversion of sterol-8-ene to the sterol-7-ene isomer in eucaryotes. To examine the regulatory mechanism as well as molecular characteristics of the isomerase we investigated the consequences of alteration of the enzymic activity under various diet conditions. Feeding 5% cholesterol or 0.1% AY-9944 for a minimum of 2 days caused more than a 70% decrease in microsomal isomerase activity. Feeding 5% cholestyramine plus 0.1% lovastatin (CL-diet) for 7 days led to approximately 4.0-fold induction of the isomerase activity. In addition, diurnal variation in the enzymic activity was observed with this diet. Induction of the isomerase activity by the CL-diet was quantitatively reflected in an increase in the cholesterol synthetic rate in isolated rat hepatocytes. The isomerase was highly purified from liver of rats fed the CL-diet, and its molecular mass was determined to be 21,000 Da by denaturing sodium dodecylsulfate gel electrophoresis.

Koebner reaction in psoriasis due to secondary syphilis

A patient with a two-year history of psoriasis showed a widespread eruption that was clinically and histologically similar to psoriasis. Results of blood tests revealed syphilitic infection, appearing to be secondary syphilis. The flare-up of guttate psoriasis was considered to represent a Koebner phenomenon due to secondary syphilis.