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Notes: This study compared the fine structure of macromelanosomes with that of giant melanosome complexes formed through melanosomal autophagocytosis in nevocytes and melanocytes of nevocellular nevi, lentigo simplex and malignant melanoma. While macromelanosomes were found only on rare occasions in these pigmentary disorders [2 of 79 nevocellular nevi (2 junctional nevi), 3 of 12 lentigo simplex and 2 of 93 malignant melanoma], the giant autophagic melanosome complexes were always present, indicating that macromelanosomes are not synthesized simply through melanosomal autophagocytosis. Although both macromelanosomes and giant melanosome complexes exhibited acid phosphatase activity similar to melanosomes, they showed many different ultrastructural features. Characteristically, macromelanosomes contained numerous vesiculoglobular bodies, whereas these bodies were absent in giant melanosome complexes. In those tissues where the presence of macromelanosomes had been ruled out by light microscopy, none of the giant melanosome complexes revealed ultrastructural features indicative of macromelanosomes. Various phases of melanosomal degradation were seen, indicating that they were not simply end-products of lysosomal degradation of melanosomes. It was thought that the key process in the development of macromelanosomes was the accumulation of vesiculoglobular bodies.

Notes: In order to characterize the benign and malignant proliferation of lymphoid cells in skin, we compared surface markers and cytoplasmic organelles of cells in cutaneous lymphoid hyperplasia (CLH), lymphomatoid papulosis (LP), mycosis fungoides (MF), Sézary's syndrome (SS) and primary cutaneous malignant lymphoma (ML). The immunohistochemical study showed cells with both T- and B-cell markers in CLH, LP and early MF, whereas cells with only the T-cell marker were seen in late MF, SS and ML. T-cells in all cutaneous lesions possessed the surface marker common to T-cells of peripheral lymph nodes, and not that of central thymus cells. Cutaneous T-cells contained clustered or scattered dense core granules. Although no specific organelles indicative of benign or malignant lymphoid proliferation were found, there were several ultrastructural features that could help identifying each form of cutaneous lymphoid lesions. These included clustered or scattered dense-core granules, the variable degree of nuclear convolutions as well as dendritic arborization, and the presence or absence of 10 nm filaments.

Notes: In order to identify a means to reduce the scar formation of the skin after incision, this study examined the wound healing effect of bFGF in humans. BFGF was administered at dose of 0.1 and 1 μg per cm of sutured immediately after an operation. The drug was injected once into the dermis of the margins of wounds using a 27 G needle attached to a 1-ml syringe to the patients. The lengths of the treated wounds varied from 1.5 cm to 23 cm, and the subjects were 2 to 76 years old. Sutured wounds after excision of skin tumors from the face, trunk and limbs and the sutured wounds such as those at the donor sites of full thickness skin grafts were treated with low dose bFGF injections. Postoperative administration of bFGF, inhibited scaring and accelerated healing without any serious side effects. Although double–blind studies are needed, we expect that so-called scar-less surgery may be possible by establishing of more sophisticated methods for administering bFGF and its combination with other drugs and/or gene therapy in the future.

Notes: Apoptosis has been shown to play an important role in the regulation of wound healing, and growth factors can mediate this process. In this study, we examined the relationship between the degree of healing and the level of apoptosis in full-thickness-incisional skin wounds, which were treated by conventional suturing with or without intradermal injection of bFGF (0.1 μg and 1 μg/cm of wound). The width of wound tissue showed that the degree of granulation formation in the 1 μg-bFGF-treated group significantly increased on day 7, whereas the degree of scar formation significantly decreased on days 14 and 28. Similarly, apoptotic cells significantly increased in the number on day 4 in the 1 μg-bFGF-treated group compared with that of the control group (p = 0.024), and decreased on days 14 and 28. These findings therefore, suggest that the accelerated apoptosis in the bFGF-treated wounds contributes to the decreased cellularity in inflammatory change through elimination of cells with apoptosis, which resulted also in the reduction of scar formation. It therefore hypothesized that apoptosis is involved in the maturation of an acute wound into scar formation, and that bFGF can accelerate this process.

Notes: Hepatocyte growth factor (HGF) is a ligand for the c-Met receptor tyrosine kinase. This study was aimed to characterize the role of the HGF gene combined with basic fibroblast growth factor (bFGF) protein in wound healing by administering both of them locally to acute incisional skin wounds created on the backs of rats. The bFGF protein and the HGF gene were administered intradermally after incisional surgery. Apoptotic cells in wound lesions were identified by the terminal deoxynucleotide transferase-mediated nick-end labeling method, as well as by immunological detection of active caspase-3. While there was almost complete suppression of apoptosis with well-organized wound healing in animals treated with the HGF gene, the combination of bFGF protein and the HGF gene paradoxically resulted in less scarring along with the promotion of apoptosis. Histopathological examination revealed that scar formation was least apparent in rats treated with both bFGF and the HGF gene compared with controls or those treated with the bFGF or the HGF gene alone. It is thought that the combined administration of bFGF and the HGF gene immediately after skin incision may make the healing process occur closer to tissue regeneration through the induction of apoptosis, which occurred 1 week after surgery. HGF supplementation through gene therapy combined with bFGF protein may be an effective strategy for treating wounds, as it increases the apparent regeneration of the dermis to allow for “scarless wound healing.”

Notes: Summary Previous in vivo studies have shown that 4-S-cysteaminylphenol (4-S-CAP) and N-acetly-4-S- cysteaminylphenol (N-Ac-4-S-CAP) have antimelanoma effects and that N-Ac-4-S-CAP produced a 98% depigmentation of hair follicles of black mice. This study investigated the process of selective melanocytotoxicity by N-Ac-4-S-CAP through light and electron microscopy studies of hair follicles obtained from newborn black mice treated with N-Ac-4-S-CAP. Visible changes in follicular melanocytes were found 4h after intraperitoneal (i.p.) adminstration. Clumps of melanin granules and areas of melanocytic nuclear condensation were seen in the hair follicles. On electron microscopy there was progressive destruction of melanoctyes with swelling of membranous organelles, nuclear condensation, and vacuolation of the cytoplasm, culminating in completely necrotic cells. None of thes changes were demonstrated in the surrounding keratinocytes. N-Ac-4-S-CAP appears to have specific, cytotoxic effects on melanocytes actively producing eumelanin. The drug may not affect precursor or dormant melanocytes whic retain the ability to become active, melanin-producing cells.

Notes: A 21-year-old woman with recurrent skin lesions present since December 1992 was seen at the University of Alberta hospitals in 1994. The skin lesions consisted of pruritic, painful, erythematous, “beefy” plaques on the trunk and extremities and also of vesicles, bullae, and pustules on the ankles and hands. She experienced numerous flare-ups of her eruption that required hospital admission on five separate occasions. Each episode was associated with sweats, chills, and dizziness. Headaches, arthralgias, myalgias, and generalized fatigue occurred on occasion. Previous skin biopsies suggested Wells' syndrome. Detailed investigations did not reveal any underlying etiology.The patient was a single woman who had recently moved from New Brunswick to live with her aunt and two cousins in Edmonton and to find employment. She had previously been a healthy young woman until her episodes first began in December 1992. There was a personal history of childhood atopic dermatitis, but she denied any other manifestations of atopy. Her mother had recently passed away at the age of 37 from Hodgkin's lymphoma, otherwise the family history was unremarkable. At the time of this admission she was not taking any medications; however, during the previous months in New Brunswick she had been using numerous medications including prednisone, dapsone, colchicine, and an oral contraceptive for a functional ovarian cyst. Prednisone, up to 60 mg/day, had initially appeared beneficial for her skin lesions, but later her symptoms became resistant. In addition, she suffered from many side-effects induced by chronic corticosteroid usage, inciuding biurred vision, weight gain, striae, and irreguiar menstruai periods. She had not been on corticosteroids for the past 6 weeks, and none of the other medications were of benefit. In fact, she had suffered a severe idiosyncratic reaction to dapsone consisting of high fever, abdominai pain, and abnormal liver parameters. There was no significant travel history and she denied any drug abuse or HIV risk factors, the patient was an animal lover and often played for hours at a time with her aunt's dog and two cats. By coincidence, in New Brunswick she had also owned a dog and two cats. A review of systems was unremarkable. On physical examination, she was a moderately obese young woman who appeared cushingoid, but otherwise well. She was afebrile. Examination of the skin revealed multiple vesicles, bullae, and pustules on her hands and fingers, involving both dorsal and palmar surfaces and extending to her wrists (Fig. 1). Some of the lesions had broken open forming overlying crusts. A few bullae had become hemorrhagic. There was an obvious foul-smelling odor emanating from the lesions. Multiple small excoriations were present bilaterally on the shins and two erythematous, edematous papules were seen on the abdomen. A live flea was found in her suprapubic area. No other fleas were found. The rest of the general examination was unremarkable. Pertinent laboratory investigations revealed an absolute eosinophilia of 2700/mm3 (24% eosinophilia) with a white blood count (WBC) of 11,400/mm”. Swabs of hand lesions were culture-positive for multiple aerobes and anaerobes: 3+ growth of Staphylococcus aureus, 3+ growth of Haemophilus parainfluenza, 1 + growth of Coxiella oxytoca, 2+ growth of Streptococcus viridans, and 4-i- growth of mixed anaerobes. Virologic tests were negative. Examination of a skin biopsy specimen (Fig. 2) revealed multiple flame figures in the dermis with surrounding and interspersed eosinophils. Numerous eosinophils, / lymphocytes, and histiocytes were also present around small blood vessels. There were degenerative changes of the upper epidermis with spongiosis, suggestive of early intraepidermal vesicle formation. Direct immunofluorescence on skin specimens was negative. Skin prick testing with flea antigen was positive for immediate hypersensitivity, but negative for a delayed reaction after 48 h.On further questioning, the patient admitted that she had played with a cat just prior to her admission, which, unbeknownst to her at the time, was flea-infested. Her aunt strongly denied any fleas in the home environment, despite her pets. No other household members complained (5f insect bites or skin symptoms. The patient's skin improved remarkably with hospitalization and treatment with antibiotics; no new lesions developed while in hospital and she was discharged 12 days later. She continued to experience recurrent, sporadic eruptions that resolved without corticosteroids, but was later lost to follow-up when she returned home to New Brunswick.

Notes: A 58-year-old Japanese man visited our clinic in December 2000 with a complaint of an erythematous plaque with reddish papules and pigmentation on the penis shaft and glans. He noticed the lesion 1 month before his visit. He denied any previous homosexual activity. His wife denied any genital skin lesion or gynecologic abnormality. No history of human immunodeficiency virus infection could be obtained.Physical examination of the skin lesion revealed an asymptomatic, flat-topped, approximately 10-mm-sized, reddish-brown keratotic plaque on the penis shaft. It showed an irregular surface, irregular border, and color variegation. Multiple, small, reddish-brown papules and plaques were distributed on the surrounding penis shaft and glans (〈link href="#f1"〉Fig. 1). The patient had no symptomatic signs. No lymphadenopathy was noted in the inguinal area.〈figure xml:id="f1"〉Figure 1 〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1307_1:IJD_1307_f1"/〉Clinical features of BP lesions on the penis. A keratotic plaque shows an irregular surface, irregular border, and color variegation, and is surrounded by small, reddish-brown papulesA biopsy specimen revealed parakeratosis and an irregularly acanthotic epidermis composed of abnormal keratinocytes exhibiting cellular atypia and mitotic figures. The tumor cells had large, hyperchromatic, and pleomorphic nuclei (〈link href="#f2"〉Fig. 2). These lesions were diagnosed as bowenoid papulosis (BP). For treatment, an operative excision with a 3 mm margin was performed.〈figure xml:id="f2"〉2〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1307_1:IJD_1307_f2"/〉Histologic features of the BP lesion. A parakeratotic and irregularly acanthotic epidermis is composed of abnormal keratinocytes exhibiting cellular atypia and mitotic figures. The tumor cells have large, hyperchromatic, and pleomorphic nucleiDNA was extracted from blocks of BP and non-BP, normal-looking skin tissue. Polymerase chain reaction (PCR) was performed utilizing L1 consensus primer set MY09 and MY11 (Bernard HU, Chan SY, Manos MM, et al. Identification and assessment of known and novel human papillomaviruses by polymerase chain reaction amplification, restriction fragment length polymorphisms, nucleotide sequence, and phylogenetic algorithms. J Infect Dis 1994; 170: 1077–1085). MY09/11 consensus PCR generated an approximately 450-base-pair fragment from all of the samples (〈link href="#f3"〉Fig. 3). Nucleotide sequencing revealed that the amplified L1 sequences were identical to that of human papillomavirus (HPV) type 16 (nucleotide positions 6582–7018). All of the L1 sequences from the BP lesion and the normal regions were identical. Our case contained the prototype sequence reported by Dürst et al. (Dürst M, Gissmann L, Ikenberg H, zur Hausen H. A papillomavirus DNA from a cervical carcinoma and its prevalence in cancer biopsy samples from different geographic regions. Proc Natl Acad Sci USA 1983; 80: 3812–3815).〈figure xml:id="f3"〉3〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1307_1:IJD_1307_f3"/〉Amplification of the L1 sequence from a BP lesion and surrounding tissues. The polymerase chain reaction was carried out using MY09 and MY11 consensus primers. Lanes from left to right: M, 1-kilobase ladder marker; N, negative control (H2O); P, positive control (HPV16 DNA); 1, DNA from BP lesion; 2 and 3, DNA from surrounding tissues consisting of normal skin. An arrow indicates the 450-base-pair bands

Notes: A case of a 17-year-old Japanese-Canadian boy with a 2-year history of skin lesions relevant to confluent and reticulated pa-pillomatosis (CRP) is reported with electron microscopic findings. He had scattered skin lesions of brownish-colored, rough-surfaced, fine-scaled patches and plaques distributed on the nape, shoulders, and both flanks, extending to the chest and back. Importantly, they showed reticular or confluent arrangement. There was no family history of the same skin lesions. The histology showed epidermal papillomatosis and mild acanthosis with a marked hyperkeratosis. Electron microscopically, the skin lesions consisted of the following abnormal findings: (1) a marked alteration of cornified cell structures showing snake coil-like, or triangle-like stacks, (2) a marked increase in the number of lamellar granules in the granular layer, (3). an increased number of melanosomes in the horny layers, and (4) no significant fine structural changes of epidermal melanocytes. This is the first electron microscopic report on CRP suggesting that the pathophysiology of this disease is related to abnormal keratinocyte differentiation.