A DNA sequence element that advances replication origin activation time in Saccharomyces cerevisiae.

Eukaryotic origins of DNA replication undergo activation at various times in S-phase, allowing the genome to be duplicated in a temporally staggered fashion. In the budding yeast Saccharomyces cerevisiae, the activation times of individual origins are not intrinsic to those origins but are instead governed by surrounding sequences. Currently, there are two examples of DNA sequences that are known to advance origin activation time, centromeres and forkhead transcription factor binding sites.

Helmets prevent motorcycle injuries with significant economic benefits.

Objective: The number of registered motorcycles in the United States has been steadily increasing, as have the number of motorcycle injuries and fatalities. The Midwest has the lowest incidence of helmet use in the country. Iowa in particular has no helmet law.

Tufted angioma.

A 4-month-old girl developed coalescing, red-purple, firm plaques with irregular borders and superimposed papules in the left groin. The lesions were tender to palpation and they slowly expanded and became thicker over the next year. Histopathologic evaluation showed multiple, discrete lobules of tightly packed capillaries in a 'cannonball' pattern within the dermis, which confirmed the diagnosis of tufted angioma.

The temporal program of chromosome replication: genomewide replication in clb5{Delta} Saccharomyces cerevisiae.

Temporal regulation of origin activation is widely thought to explain the pattern of early- and late-replicating domains in the Saccharomyces cerevisiae genome. Recently, single-molecule analysis of replication suggested that stochastic processes acting on origins with different probabilities of activation could generate the observed kinetics of replication without requiring an underlying temporal order. To distinguish between these possibilities, we examined a clb5Delta strain, where origin firing is largely limited to the first half of S phase, to ask whether all origins nonspecifically show decreased firing (as expected for disordered firing) or if only some origins ("late" origins) are affected.

ILVEN-like persistent psoriasiform dermatitis confined to a congenital Becker nevus.

A 10-year-old boy presented with a 5-year history of an intractably pruritic, recalcitrant psoriasiform plaque in a broad vertical band on the left buttock, with histologic as well as clinical features suggestive of an inflammatory linear verrucous epidermal nevus. This lesion was completely superimposed upon a congenital Becker nevus. We postulate that the restricted distribution and persistence of the psoriasiform plaque reflected an inflammatory response limited to the aberrant clone of cells composing the Becker nevus, a manifestation of cutaneous mosaicism that could be characterized as an "inflammatory Becker nevus.

"Pediatric blaschkitis": expanding the spectrum of childhood acquired Blaschko-linear dermatoses.

We describe two young children who developed relapsing, pruritic, papulovesicular eruptions in multiple bands along Blaschko lines on the neck, trunk, and extremities. Skin specimens in both revealed spongiotic dermatitis. This represents the first report of "blaschkitis" in children, providing further evidence that lichen striatus and blaschkitis are related acquired Blaschko-linear dermatoses that exist on a spectrum rather than as the childhood and adult form of a single disease entity.

Structural changes in Mcm5 protein bypass Cdc7-Dbf4 function and reduce replication origin efficiency in Saccharomyces cerevisiae.

Eukaryotic chromosomal replication is a complicated process with many origins firing at different efficiencies and times during S phase. Prereplication complexes are assembled on all origins in G(1) phase, and yet only a subset of complexes is activated during S phase by DDK (for Dbf4-dependent kinase) (Cdc7-Dbf4). The yeast mcm5-bob1 (P83L) mutation bypasses DDK but results in reduced intrinsic firing efficiency at 11 endogenous origins and at origins located on minichromosomes.

Keratosis follicularis (Darier-White disease), with an unusual palmoplantar keratoderma.

A 38-year-old woman presented with widespread, hyperkeratotic papules and plaques that had been present since childhood. Her mother, brother, and son have similar lesions. A diagnosis of keratosis follicularis was made, which has been treated with isotretinoin.

Hepatitis C virus infection, type III cryoglobulinemia, and necrotizing vasculitis.

A 53-year-old man with chronic hepatitis-C virus infection presented with livedo reticularis, purpura, and leg ulcers. A skin biopsy specimen showed a necrotizing vasculitis. The skin biopsy specimen and serology confirmed the diagnosis of type-III cryoglobulinemia.

Folliculotropic mycosis fungoides.

A 72-year-old man presented with a 4-year history of asymptomatic erythematous plaques on his face, neck, and scalp. He had no systemic symptoms or lymphadenopathy. Histopathologic examination of a skin biopsy specimen showed a dense, diffuse infiltrate of lymphocytes and plasma cells, with epidermotropism and folliculotropism.

Familial multiple angiolipomatosis.

An 80-year-old man presented with a 50-year history of asymptomatic, subcutaneous masses on the arms, trunk, and legs. His father and maternal grandmother had had similar lesions. Histopathologic examination showed a benign angiolipoma; the same diagnosis has been made on several previous biopsy specimens.

Acroangiodermatitis.

A 26-year-old man with a history of chronic primary lymphedema of the left lower extremity presented with elephantiasis, confluent, violaceous, mascerated plaques, and ulcers on the dorsal aspects of the toes of the left foot. Histopathologic examination showed a proliferation of small blood vessels associated with extravasated erythrocytes and hemosiderin deposits consistent with the diagnosis of acroangiodermatitis. Treatment of the focal ulcers includes compression therapy, local wound care, and surgical elimination of the shunt if there is an associated arteriovenous malformation.

Self-healing juvenile cutaneous mucinosis: cases highlighting subcutaneous/fascial involvement.

Background: Self-healing juvenile cutaneous mucinosis is a rare disease affecting young people characterized by transient cutaneous lesions and sometimes mild inflammatory symptoms. The deep dermal and subcutaneous features of this disorder have not yet been well described.

Objective: The purpose of our study was to present 3 cases of self-healing juvenile cutaneous mucinosis in which the histopathologic features caused diagnostic confusion between this disorder and proliferative fasciitis.

Genomic mapping of single-stranded DNA in hydroxyurea-challenged yeasts identifies origins of replication.

During DNA replication one or both strands transiently become single stranded: first at the sites where initiation of DNA synthesis occurs (known as origins of replication) and subsequently on the lagging strands of replication forks as discontinuous Okazaki fragments are generated. We report a genome-wide analysis of single-stranded DNA (ssDNA) formation in the presence of hydroxyurea during DNA replication in wild-type and checkpoint-deficient rad53 Saccharomyces cerevisiae cells. In wild-type cells, ssDNA was first observed at a subset of replication origins and later 'migrated' bi-directionally, suggesting that ssDNA formation is associated with continuously moving replication forks.

Postradiation sarcoma: case report and review of the potential complications of therapeutic ionizing radiation.

Background: Radiation therapy is an acceptable treatment choice for many cutaneous malignancies. A potential late sequela of ionizing radiation is the development of secondary neoplasms within the treatment field. Although there are well-known cutaneous syndromes in which the use of ionizing radiation is contraindicated, in other clinical situations, physicians may not fully realize the risks associated with this therapeutic modality.

Precalcaneal congenital fibrolipomatous hamartomas: report of occurrence in half brothers.

Precalcaneal congenital fibrolipomatous hamartomas are uncommon, congenital, nontender papules located on the medial plantar aspects of the heel. We report the occurrence of this rare disorder in two half brothers, suggesting that it may occur in a familial pattern.

Hypertrophic herpes simplex virus in HIV patients.

In conclusion, HSV lesions in HIV patients can present as chronic, hyperproliferative plaques as opposed to the classic acute ulcerative lesions. Knowledge of this presentation will motivate the physician to be diligent in the diagnostic workup. This may necessitate repeat biopsies and cultures.