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Notizen: Case 1 A 6-month-old boy presented to our clinic with a scalp lesion dating since birth (〈link href="#f1"〉Fig. 1). The lesion was in the form of an erythematous, dome-shaped nodule, measuring around 1.5 cm in diameter and having a slightly irregular surface. The lesion was nonitchy, nontender, and showed limited mobility. Our clinical differential diagnosis included: meningocele, hemangioma, dermoid cyst, and apocrine nevus. A computed tomography (CT) scan was performed to exclude possible intracranial connection, and the lesion was surgically excised.〈figure xml:id="f1"〉1〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1245:IJD_1245_f1"/〉Case 1: erythematous nodule on the occipital area of a 6-month-old boy. The lesion was clinically suggestive of apocrine nevus, dermoid cyst, or meningoceleHistopathologic examination (〈link href="#f2"〉Fig. 2) revealed a markedly dilated follicular cystic structure, with numerous sebaceous lobules arising from its wall. Other cystic structures containing keratin, but no hair, were also seen. There were numerous sebaceous lobules, excess fibrous tissue (showing a lamellar pattern around the cystic structures and sebaceous lobules), and excess fatty tissue, but no muscles of hair erection were found in the lesion. Clefts were seen separating the pericystic fibrous tissue from the rest of the dermis. Collections of blood vessels were detected in the lower part of the lesion. These features are characteristic and seen only in folliculo-sebaceous cystic hamartoma.〈figure xml:id="f2"〉2〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1245:IJD_1245_f2"/〉large infundibular cystic structure with numerous sebaceous lobules and rudimentary follicles arising from its wall. Individual sebaceous lobules are seen surrounding the cyst. Lamellar fibrous tissue is seen around the cyst and separated from the surrounding stroma by clear clefts. Numerous blood vessels, muscle fibers, and adipose tissue are seen in the lower part (× 100) Case 2 A 55-year-old woman presented with two erythematous, dome-shaped nodules on the scalp of more than 10 years' duration (〈link href="#f3"〉Fig. 3). Each lesion measured about 1 cm in diameter, exhibited soft consistency, and showed limited mobility. Apart from the unsightly appearance, the lesions were symptomless. The clinical differential diagnosis included: intradermal nevus, apocrine nevus, nevus sebaceous, and syringocystadenoma papilliferum.〈figure xml:id="f3"〉3〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1245:IJD_1245_f3"/〉Case 2: skin-colored nodules on the back of the scalp of a 55-year-old womanMicroscopic examination (〈link href="#f4"〉Fig. 4) revealed a mid-dermal cystic structure lined by follicular epithelium with numerous rudimentary hair follicles and sebaceous lobules arising from its wall. There were also numerous sebaceous lobules, as well as excess fibrous and fatty tissue. Clefts were seen separating the lamellar pericystic fibrous tissue from the rest of the dermis. These features are diagnostic of folliculo-sebaceous cystic hamartoma.〈figure xml:id="f4"〉4〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD1245:IJD_1245_f4"/〉Infundibular cystic structure not connected to the overlying epidermis showing the same features as in 〈link href="#f2"〉Fig. 2, with a large number of isolated sebaceous lobules. There is pericystic compact lamellar fibrous tissue separated from the surrounding stroma by clear clefts (× 100)

Notizen: Background  Familial gigantic melanocytosis (FGM) is a rare disorder first described in 1984 and termed “familial melanopathy with gigantic melanocytes”. The cause of the disorder is still unknown. Melanocytes in both hyper- and hypopigmented skin seem to be unable to deliver melanin to the surrounding keratinocytes.Objective  In this study, we report four new cases of FGM. Electron microscopic examination was performed in a trial to shed more light on the underlying defect in this disorder.Patients and methods  Patients were examined clinically and biopsies were taken from both hyperpigmented and hypopigmented areas, and divided into two parts; one part was processed for routine microscopic examination with hematoxylin and eosin and Masson Fontana stains. The other portion of the biopsy was fixed in glutraldhyde 3% and processed for electron microscopic (EM) examination.Results  By light microscopy, the patients’ skin showed areas of hyperpigmented basal cells alternating with poorly pigmented areas. Hair follicles in the scalp biopsies showed the same pathology. By EM, pigmented areas showed gigantic melanocytes and heavily pigmented keratinocytes. Nonpigmented areas showed poorly pigmented keratinocytes and fewer, but also gigantic melanocytes.Conclusions  The raindrop-like hypopigmentation in this disorder can be explained by a failure of melanocytes to deliver melanin to their surrounding keratinocytes. The cause of the presence of heavily pigmented keratinocytes in the hyperpigmented zones could not be determined. There is a strong possibility of a more widespread abnormality affecting not just the melanocytes.

Notizen: Basaloid follicular hamartoma (BFH) is a unique benign follicular hamartoma characterized by variable clinical presentations, identical histologic features and possible associations with numerous disorders.Basaloid follicular hamartoma may be hereditary or acquired. Hereditary cases may be either generalized or unilateral nevoid. Although the generalized forms are usually associated with systemic manifestations, such as myasthenia gravis,2 it may occasionally present without internal disorders. On the other hand, the acquired forms of BFH may present in the form of localized or solitary forms.Herein we present four cases of BFH, one of them (first case) represents a unique form of the generalized variant of BFH, showing no associated internal disorders.

Notizen: [Auszug] We have reported evidence for regularity in periodic awakening of ground squirrels from hibernation as follows: (1) hamsters and ground squirrels were maintained all summer at control temperatures with a daily cycle of 12 hr. of artificial light and 12 hr. of darkness; (2) they were then permitted ...

Notizen: Despite its wide acceptance in economics, the fundamental tenet of the theory of the firm is not without its critics. Questions related to the nature and role of the firm, its objectives, responsibilities and behavior have fueled much of the recent debate. Today, firms are being evaluated and scrutinized not merely on their economic performance, but also by the ethical standards they uphold. The case brought against Microsoft is an example of the tangled web that characterizes the economic, legal and ethical dimensions of business operations. This paper shows that as an economic entity, Microsoft employed strategies that were consistent with its long-run objective of profit maximization. In so doing, however, Microsoft violated anti-trust laws and was charged with illegal conduct. Despite the court ruling, economic and legal justifications continue to be a subject of debate amongst the different entities involved in this case. More so when ethical implications are considered, consensus becomes even harder to reach due to the subjective nature of the judgement.

Notizen: The dynamic responses of a bench-scale activated-sludge process to step changes and square-wave inputs in the feed flow and concentration were measured. Instrumentation permitted the continuous measurement of the oxygen uptake rate and dissolved organic carbon responses. Notable were the sensitivity of the oxygen uptake rate to process changes and the reliability of the dynamic oxygen electrode method. The responses were found to be greatly influenced by the organic loading, FS0/XV, which was incorporated into a load-dependent kinetics model. Simulations showd good agreement with experiment in the case of the square-wave disturbances. Because of the changing and complex nature of the activated sludge it was necessary to reestimate the parameter set for each run.