Ultrastructural observations on mitochondria and microvesicles in renal oncocytoma, chromophobe renal cell carcinoma, and eosinophilic variant of conventional (clear cell) renal cell carcinoma

On light microscopic examination, the morphologically overlapping features of granular eosinophilic cytoplasm in renal oncocytoma and the eosinophilic variants of chromophobe renal cell carcinoma and conventional (clear cell) renal cell carcinoma may pose difficulties in diagnosis. We investigated the ultrastructure of 5 renal oncocytomas, 7 eosinophilic variants of chromophobe renal cell carcinoma, and 5 eosinophilic variants of conventional (clear cell) renal cell carcinoma. Special attention was paid to mitochondria and microvesicles and interrelations thereof. The electron microscopic features were correlated with the light microscopic findings. All of the tumors had abundant mitochondria. Although abundant microvesicles were present in all of the chromophobe renal cell carcinomas, scant numbers of microvesicles were also sometimes present in renal oncocytomas (2 of 5) and in the eosinophilic variant of conventional (clear cell) renal cell carcinoma (1 of 5). The mitochondria in all three types of renal neoplasms studied differed in morphology, being predominantly uniform and round with predominantly lamellar cristae in renal oncocytoma, variable in shape and size with predominantly tubulocystic cristae in chromophobe renal cell carcinoma, and swollen and pleomorphic with rarefied matrix and attenuated cristae in the eosinophilic variant of conventional (clear cell) renal cell carcinoma. Variable numbers of mitochondria in all of the chromophobe renal cell carcinomas had outpouchings of the outer membranes, some of which carried parts of inner membrane within them. These outpouchings closely resembled the nearby cytoplasmic microvesicles, as did the tubulocystic cristae of the mitochondria. Some microvesicles contained homogeneous, electron-dense, finely granular matrix, similar to that seen in mitochondria. In one of seven chromophobe renal cell carcinomas, microvesicles were present in rough endoplasmic reticulum, and in two others, mitochondria were present within some vesicles. These features strongly suggest a close relationship between the microvesicles and mitochondria. Based on the role of vesicle formation in normal mitochondriogenesis, and some of our observations, we propose that defective mitochondriogenesis may be the source of microvesicles in chromophobe renal cell carcinomas.

Diarylheptanoids with in vitro inducible nitric oxide synthesis inhibitory activity from Alnus hirsuta

Four diarylheptanoids were isolated from the leaf of Alnus hirsuta (Betulaceae) and have been assessed for nitric oxide (NO) production inhibitory effects in vitro. Oregonin (1) and hirsutanonol (2) were found to be potent inducible nitric oxide synthase (iNOS) inhibitors. Compounds 1 and 2 showed inhibition of NO synthesis in dose-dependent manners by murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). Their 50% inhibitory concentrations (IC50) were 3.8 and 14.3 microM, respectively. The inhibitory effects of these compounds on NO synthesis were due to suppression of iNOS mRNA expression as determined by Northern blotting.

A case of mycosis fungoides after CD30 positive anaplastic large cell lymphoma

A 55-year-old woman presented with mycosis fungoides (MF) after the total excision of primary cutaneous CD30+ anaplastic large cell lymphoma (ALCL). In the specimens obtained from the nodule of CD30+ ALCL and the plaque lesion of MF, the same pattern of T-cell receptor gene rearragement was detected.

New paradigm, new market and new theatre in ergonomics

Change is the only constant in today's technology-driven world. As industry moves towards an unprecedented revolution, the momentum and impact of the change are both rapid and profound. This will affect our profession drastically. We will need to redefine our goals and strategies to cope with these new challenges. In this paper, a new paradigm of thinking, a new market for our discipline and a new theatre of ergonomics in the future are proposed and explained.

Linear eruptions of the nose in childhood: a form of lichen striatus?

We report four children with linear eruptions on the nose, with overlapping features of lichen striatus and linear cutaneous lupus erythematosus. However, linear lupus erythematosus has rarely been reported, and lichen striatus, although classically linear, rarely affects the face. The linear distribution of lesions from the glabella to the ala nasi may represent distribution following Blaschko's lines.

Inhibition of cyclooxygenase-2 expression by diarylheptanoids from the bark of Alnus hirsuta var. sibirica

Two known diarylheptanoids, oregonin (1), (5S)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-3-one-5-O-beta-D-xylopyranosi de and hirsutanonol (2), (5S)-1,7-bis-(3,4-dihydroxyphenyl)-5-hydroxyheptane-3-one isolated from the bark of Alnus hirsuta var. sibirica, showed significant inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cyclooxygenase-2 (COX-2) expression in immortalized human breast epithelial MCF10A cells.

Hyalinizing Spitz nevus

A seventeen-year-old Korean girl had a reddish-brown papular lesion on the nose. Histopathologically, it proved to be a "hyalinizing Spitz nevus" with the characteristic features of a discohesive growth pattern of nevus cells and hyalinized stroma. Immunohistochemical stains showed positive reactivity of nevus cells with S-100 protein and Vimentin and negative stainings with HMB45, CD68, CEA and low molecular weight cytokeratin. Hyalinizing Spitz nevus may represent a variant in the spectrum of Spitz nevus.

Effect of vitamin D nutrition on parathyroid adenoma weight: pathogenetic and clinical implications

In primary hyperparathyroidism, adenoma size is a major determinant of disease severity and manner of presentation, but the reason for the large variation in size (>100-fold) is unknown. One factor could be the level of vitamin D nutrition, because in India, where vitamin D deficiency is endemic, adenomas are larger and the disease more severe than in the U.S. Accordingly, we determined the relationship between vitamin D nutrition, as measured by serum levels of 25-hydroxyvitamin D (25OHD), and parathyroid gland weight, expressed on a logarithmic scale, in 148 U.S. patients with primary hyperparathyroidism. A significant inverse relationship was found between log gland weight as dependent variable and serum 25OHD as independent variable (r = -0.365; P < 0.0001). The only other influence on gland weight was a weak inverse correlation with age. Log gland weight as an independent variable was significantly related to adjusted calcium, PTH, and alkaline phosphatase (AP) as dependent variables. In 51 patients with serum 25OHD levels less than 15 ng/mL, gland weight, PTH, AP, and adjusted calcium were each significantly higher than in 97 patients with 25OHD levels of 15 ng/mL or more, but 1,25-dihydroxyvitamin D levels were similarly increased in both groups. In the former group the response of adjusted calcium to PTH was blunted, and the response of AP was enhanced, based on significant differences in regression slopes (P = 0.0004 and 0.0022, respectively). Suboptimal vitamin D nutrition stimulates parathyroid adenoma growth by a mechanism unrelated to hypocalcemia or 1,25-dihydroxyvitamin D deficiency and reduces the calcemic response to PTH, so that a higher PTH level and more parathyroid cells are needed to raise the patient's serum calcium to the level corresponding to the increased set-point that is characteristic of the disease. Improved vitamin D nutrition in the population is partly, perhaps largely, responsible for the historical changes in disease severity and manner of presentation that have occurred over the last 50 yr.

Phakomatous choristoma: a case report and review of the literature

Phakomatous choristoma is a rare congenital lesion of the eyelid that can be clinically and/or histologically mistaken for a cyst, cutaneous adnexal neoplasm, or an ocular adnexal oncocytoma. Only 13 such cases have been previously described, mostly in the English language ophthalmic literature. Zimmerman reported the first case in 1971 and proposed the lesion to be of lenticular anlage origin, a theory that has been widely accepted. We report an additional case occurring in an 8-week-old male infant with a firm nodule of the right lower eyelid that was present since birth. A 15 x 12 x 2 mm circumscribed solid nodule with a homogenously white cut surface was surgically excised. Histologically, this lesion was comprised of cuboidal cells forming cystically dilated and irregularly branched ducts and cords within a densely fibrotic stroma. Also present were eosinophilic basement membranelike material, psammoma body-like calcifications and intraluminal degenerated ghost cells. The immunohistochemical profile of the epithelial cells included strong immunoreactivity for vimentin, focal weak staining for S-100, and negative staining for cytokeratin, epithelial membrane antigen, synaptophysin, and chromogranin. The irregularity of the ducts and cords of epithelial cells within the densely fibrotic stroma resembled an infiltrative neoplasm of cutaneous adnexal or lacrimal duct origin. However, the site of involvement, the peculiar basement membrane material, ghost cells, and immunohistochemical profile were features that helped to distinguish phakomatous choristoma from an infiltrative carcinoma. The correct identification of this lesion is essential to avoid an aggressive surgical excision, thus sparing the eyelid and lacrimal system. The purpose of this article is to bring attention to this rare entity, because it has not been described in either the dermatology or dermatopathology literature and furthermore, is not mentioned in any of the major dermatopathology texts.

Diarylheptanoids from the leaves of Alnus hirsuta Turcz

Diarylheptanoids, (5S)-1,7-bis-(3,4-dihydroxyphenyl)-5-hydroxyheptane-3-one (1, hirsutanonol), (5S)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-3-one-5-O-beta-D-xylopyranosi de (2, oregonin), (5R)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-beta-D-xylopyranoside (3), and (5R)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-beta-D-glucopyranoside (4) were isolated from the leaves of Alnus hirsuta Turcz. The structures of these compounds were identified based on the spectral and physicochemical data.

Genetic changes in sweat gland carcinomas

The molecular pathogenesis of malignant appendageal tumors is poorly understood. Immunohistochemical staining, polymerase chain reaction (PCR)-based loss of heterozygosity (LOH) and sequencing analyses were performed in a mixed group of 21 sweat gland carcinomas. LOH was mostly confined to the chromosome arm 17p. None of the remaining 17 tumors showed LOH at any loci. Nuclear accumulation of p53 protein was observed in 3 tumors, all of which also showed LOH of 17p. One eccrine gland adenocarcinoma showed allelic loss of 17p and a Cys 176 Arg mutation in the p53 gene. The other three tumors that showed LOH of 17p, however, had wild-type p53 genes. A clear transition from benign eccrine poroma to porocarcinoma that was associated with p53 protein stabilization and allelic loss was observed in one tumor. One eccrine porocarcinoma/undifferentiated adnexal carcinoma showed prominent microsatellite instability, probably reflecting an underlying defect in DNA mismatch repair. Overexpression of erbB-2 was observed in three tumors. The low frequencies of LOH and p53 alterations in sweat gland carcinomas contrasted with the multiple genetic defects normally observed in cutaneous squamous cell carcinomas, and may be partly explained by the relative protection of cutaneous appendages from ultraviolet light and other environmental mutagens.

Vasoactive intestinal polypeptide stimulates the proliferation of HaCaT cell via TGF-alpha

It is well known that psoriasis, an immunogenetic cutaneous disorder whose major pathogenic findings are epidermal hyperplasia and T-cell infiltration, is aggravated by psychological stresses. Although the exact mechanism is not yet clarified, antidromic secretion of neuropeptides by cutaneous nerve fibers is thought to be involved. In this study, we examined the effect and mechanism of vasoactive intestinal polypeptide (VIP), one of the major neuropeptides, on the proliferation of HaCaT cell which is a spontaneous, immortalized, human keratinocyte cell line. Twenty-four and 48 h after its addition, 1 pM to 100 nM of VIP increased the number of cells cultured with/without serum. We indirectly verified VIP(1)R on the surface of HaCaT cell based on the proliferative ability of various VIP families such as VIP, PACAP and secretin, and increased PKA level 30 min after stimulation. However, because H-89, a PKA inhibitor, did not inhibit the proliferative potential of VIP, its mitogenicity is not medicated through VIP(1)R. One nM VIP produced the TGF-alpha protein which is a strong mitogen of keratinocytes and increased in the psoriatic lesion 2.25 times more compared with the control. Genistein, a tyrosine kinase inhibitor, abrogated the mitogenic activity of VIP. Like VIP, VIP fragments, VIP(1-12) and VIP(10-28) also acted as a mitogen for HaCaT cells through the same mechanism. Collectively, our studies clearly show that VIP and its fragments stimulate keratinocyte growth, not through increased cAMP level, but through increased TGF-alpha protein production.

Panniculitis showing membranocystic changes in the dermatomyositis

Clinically obvious panniculitis in association with dermatomyositis is rare. We reported a patient with panniculitis showing membranocystic changes in the dermatomyositis.

Assessment of body composition using dual energy x-ray absorptiometry in patients with liver cirrhosis: comparison with anthropometry

OBJECTIVES

The aim of this study was to evaluate changes of body composition in cirrhotic patients. Dual energy x-ray absorptiometry (DEXA) and anthropometry were used, and the values obtained were compared.

METHODS

Mid-arm fat and muscle areas were calculated by anthropometry in 66 cirrhotic patients and 94 healthy controls. In 37 of the cirrhotic patients and 39 of the controls, fat mass, lean soft tissue mass and bone mineral contents were measured with DEXA.

RESULTS

The number of cirrhotic patients with measured values below the fifth percentile of normal controls was 21 (31.8%) by mid-arm fat area, six (9.1%) by mid-arm muscle area, 15 (40.5%) by fat mass and 0 (0%) by lean soft tissue mass. The fat mass in cirrhotic patients was less than in controls, whereas lean soft tissue mass and bone mineral content were not different. Fat depletion was severe in Child-class C patients and with severe ascites. Mid-arm fat area and fat mass showed close correlation (r = 0.85, p < 0.01), but mid-arm muscle area and lean soft tissue mass showed poor correlation (r = 0.32, p < 0.05).

CONCLUSION

Cirrhotic patients showed lower fat component, with preserved lean soft tissue mass and bone mineral content. In clinical practice, the measurement of mid-arm fat area was useful for the assessment of fat mass.

Immunohistochemical profile of myogenin and MyoD1 does not support skeletal muscle lineage in alveolar soft part sarcoma

BACKGROUND

The histogenesis of alveolar soft part sarcoma remains elusive. Myogenic origin is favored, although conflicting data on immunohistochemical demonstration of muscle-associated markers exist. Myogenin and MyoD1, transcription factors of the myogenic determination family, have crucial roles in commitment and differentiation of mesenchymal progenitor cells to myogenic lineage and in maintenance of skeletal muscle phenotype. Their immunohistochemical detection is specific in characterization of rhabdomyosarcoma.

METHODS

Antibodies for myogenin, MyoD1, desmin, and muscle-specific actin were employed on a large series of cases (n = 19) of formalin-fixed, paraffin-embedded alveolar soft part sarcoma.

RESULTS

Minimal scattered nuclear staining was seen with myogenin. All cases had pronounced, nonspecific granular cytoplasmic immunostaining with MyoD1; nuclei were negative. All tumors were negative for desmin and muscle-specific actin. Ultrastructural study in 10 cases failed to reveal features of skeletal muscle differentiation.

CONCLUSIONS

Cytoplasmic staining with MyoD1 in alveolar soft part sarcoma may correspond to cross-reactivity with an undetermined cytoplasmic antigen. The lack of immunostaining with myogenin, MyoD1, desmin, and muscle-specific actin provides evidence against a myogenic origin for alveolar soft part sarcoma.

Cutaneous extravascular necrotizing granuloma (Churg Strauss granuloma)

Churg Strauss granuloma (cutaneous extravascular necrotizing granuloma) is a distinct entity which is associated with systemic immunoreactive or autoimmune diseases in a majority of cases. Typically, Churg Strauss granuloma presents as symmetrical papules or nodules on the extremities. There are two histological patterns: the classic pattern reveals palisading granuloma with central degenerated collagen, interspersed polymorphonuclear leukocytes, and leukocytoclastic debris; the focal basophilic necrosis pattern does not show palisading granuloma. We report two cases of Churg Strauss granuloma with different histopathological patterns.

Congenital CD34-positive granular cell dendrocytosis

Granular cell tumors involving the skin are mostly acquired lesions. The Schwann cell origin of these lesions is supported by positive immunostaining for S-100 protein and myelin basic protein. S-100- granular cell lesions rarely have been described in association with fibrous papules or dermatofibromas. The congenital variety of S-100- granular cell tumors occurs almost exclusively in the gingiva. The cell origin of these lesions is not well delineated. We report a hitherto undescribed case of a congenital cutaneous lesion which is histologically characterized by diffuse dermal infiltrates of S-100- but CD34+ granular dermal dendrocytes. The granular appearance of these CD34+ dendrocytes is attributed to an abundance of phagolysosomes. The pathogenetic mechanism of this unusual lesion remains to be elucidated.

Pagetoid Merkel cell carcinoma: epidermal origin of the tumor

We report a case of intraepidermal Merkel cell carcinoma which occurred on the face of a 76-year-old white male. This slow-growing tumor was mostly confined in the epidermis and pilosebaceous apparatus where tumor cells spread in a pagetoid fashion forming tumor cell nests. Histologically it resembled a superficial spreading melanoma. A heavy lymphocytic infiltration was seen beneath the epidermal lesion as is often seen in pagetoid melanomas. Histochemical and ultrastructural features such as the presence of cytokeratin 20, synaptophysin, neuron specific enolase, desmosomes, and dense cored granules confirmed the diagnosis of Merkel cell carcinoma. Occasional mitotic cells and many apoptotic cells were found in the tumor. Dylon positive, amyloid depositions were seen in the lower epidermis and papillary dermis; they were probably derived from apoptotic tumor cells. It was thought that apoptosis limited the speed of growth of this tumor. We believe that this is probably the most convincing case of intraepidermal Merkel cell carcinoma originating from epidermal Merkel cells or its precursors (stem cells).

Spores and mycelia in cutaneous chromomycosis

In 2 cases of cutaneous chromomycosis, potassium hydroxide preparations of lesional crust/scale easily revealed characteristic Medlar bodies. However, in both instances mycelia were also demonstrated. This contradicts the prevailing belief that concomitant spores and mycelia are found only in cerebral chromomycosis.

Effect of rebamipide on the glycosaminoglycan content of the ulcerated rat stomach

To elucidate the mechanism of the anti-ulcer effect of rebamipide (2-(4-chlorobenzoylamino)-3-[2-(1H)-quinolinon-4-yl] propionic acid), changes in glycosaminoglycan (GAG), uronic acid and hexosamine contents of stomach tissue were examined in rats treated with the ulcer-inducing agents and/or rebamipide. Uronic acid and hexosamine contents in acid hydrolysates of stomach tissue were increased after diethyldithiocarbamate (DDC, 800 mg/kg, s.c.) or histamine (300 mg/kg, i.p.) treatment, and similar changes in the GAG, uronic acid, and hexosamine levels were observed in stomach tissue extracts. Pretreatment with rebamipide (60 mg/kg, i.p.) resulted in an additional increase in the contents of the above components after DDC or histamine treatment. However, rebamipide treatment alone did not increase the gastric contents of GAG and GAG components in normal rats. Gel filtration chromatography of extracted GAGs suggested that DDC, histamine and rebamipide treatments do not cause a change in the aggregated forms of gastric GAGs. These results suggest that rebamipide stimulates the GAG synthesis in the ulcerated stomach and that this effect may contribute to the healing process of gastric ulcer.