Molecular analyses of a repetitive DNA sequence in wheat (Triticum aestivum L.).

A repetitive sequence designated WE35 was isolated from wheat genomic DNA. This sequence consists of a 320-bp repeat unit and represents approximately 0.002% of the total wheat DNA. It is unidirectionally distributed either continuously or discretely in the genome. Ladder-like banding patterns were observed in Southern blots when the wheat genomic DNA was restricted with endonuclease enzymes EcoRI, HincII, NciI, and NdeI, which is characteristic for tandemly organized sequences. Two DNA fragments in p451 were frequently associated with the WE35 repetitive unit in a majority of lambda wheat genomic clones. A 475-bp fragment homologous to the 5'-end long terminal repeat (LTR) of cereal retroelements was also found in some lambda wheat genomic clones containing the repetitive unit. Physical mapping by fluorescence in situ hybridization (FISH) indicated that one pair of wheat chromosomes could be specifically detected with the WE35 positive probe p551. WE35 can be considered a chromosome-specific repetitive sequence. This repetitive unit could be used as a molecular marker for genetic, phylogenetic, and evolutionary studies in the tribe Triticeae.

Imported African tick bite fever: a case report.

We describe a patient with African tick-bite fever who acquired his infection while visiting rural areas of South Africa and then became sick after returning to the United States. The dominant clinical feature of his illness was the presence of multiple, ulcerated lesions (tache noires). Physicians in the United States and other non-African countries who see travelers returning from southern parts of Africa who give a history of recent tick bite and/or present with multiple, crusted or vesicular skin lesions should be alert to this diagnosis and institute treatment with doxycycline.

Follicular mucinosis as a presenting sign of acute myeloblastic leukemia.

Follicular mucinosis is often associated with mycosis fungoides and has been rarely observed to occur with other neoplastic and inflammatory conditions. We describe a 60-year-old patient with follicular mucinosis who later developed acute myelogenous leukemia. This is the first reported case of follicular mucinosis as a presenting sign of acute myeloblastic leukemia in the absence of mycosis fungoides or leukemia cutis.

The great imitator: Rocky Mountain spotted fever occurring after hospitalization for unrelated illnesses.

We describe two patients who had Rocky Mountain spotted fever after they were admitted to the hospital for emergency and elective surgical procedures. We initially thought one patient had a hospital-acquired infection; the correct diagnosis was deduced from epidemiologic clues elicited by consultants. These two cases were also unusual in that one patient had a recurrent rash after an abbreviated course of low-dose doxycycline therapy and the other patient had transient and self-limiting postinfectious polyneuropathy. These cases illustrate that community-acquired infection with Rickettsia rickettsii can occur simultaneously with other disease processes and sometimes mimic a nosocomial infection.

Venous ulcers.

Successful therapy of venous ulcers combines local wound treatment modalities and ambulatory hemodynamic support to control the underlying disease. Compression bandaging reduces or eliminates edema, and a moist wound environment not only debrides necrotic tissue but also aids development of granulation tissue, a prerequisite for epidermal repair. We have occluded chronic wounds, known to be heavily colonized, with a hydrocolloid dressing for up to 7 days and found that soft-tissue infections occurred in only 1% of all dressing changes in our clinic, compared with 6.5% generally reported in the literature. In venous ulcers, resident bacteria may be beneficial in that their proteolytic activity assists with autolysis of fibrinopurulent wound exudate. The importance of lysing fibrin and reducing the number of existing fibrin "cuffs," thereby improving local tissue oxygenation and nutrient/waste exchange, is not completely understood; however, this phenomenon, in part, may explain the excellent clinical results obtained with one type of hydrocolloid dressing (DuoDERM), which has been shown to lyse fibrin more effectively than other types of moisture-retentive and hydrocolloid dressings.

Atypical presentation of inflammatory bowel disease in the elderly.

Despite multiple invasive diagnostic procedures including exploratory laparotomy and surgical resection, our patient's diagnosis remained an enigma. However, given the clinical scenario and the documented PG, a trial of steroids was warranted. The patient has fared well since her treatment, with resolution of all her symptoms. We feel confident that her disease process is most consistent with, and is most likely, Crohn's disease. There are several lessons to be learned from this case: 1) Inflammatory bowel disease can present at any age and belongs in a clinician's differential diagnosis of fever and diarrhea. 2) Failure to consider IBD in an elderly patient may lead to significant delay in diagnosis, and may expose the patient to unnecessary and sometimes dangerous intervention. 3) IBD in the elderly generally follows the same clinical patterns seen in younger patients. 4) Appropriate therapy can lead to prompt control or even resolution of the signs and symptoms of IBD.

Management of chronic and problem lower extremity wounds.

With simple, inexpensive therapy, virtually all venous ulcers heal without the need for hospitalization, skin grafting, growth factors, hyperbaric oxygen, or debilitating bed rest. Although the future promises to yield a greater understanding about the nature of these wounds and ways to treat them, one can benefit the vast majority of patients with available technology. Few therapeutic experiences are as gratifying as healing a patient's debilitating chronic wound.

Treatment of leg ulcers.

Leg ulcers represent the most common chronic wound in our population. This devastating problem often cripples patients, many of whom are in the prime of their working years. The resulting morbidity and financial cost are extraordinary. Fortunately, with the right approach, the vast majority heal with simple ambulatory outpatient therapy. The essential requirements for treating leg ulcers include a thorough understanding of lower extremity anatomy, vascular hemodynamics, and the management of trophic and inflammatory skin changes.

Treatment of lymphangioma circumscriptum with tunable dye laser.

We present the case of a patient with lymphangioma circumscriptum that was successfully treated with a flashlamp pulsed dye laser. Dermatologists are aware of the use of the pulsed dye laser for the treatment of port-wine stains and other vascular lesions. This case report illustrates the usefulness of the pulsed dye laser for the treatment of another common dermatologic condition.

Merkel cell tumor.

A case of a rapidly growing Merkel cell tumor occurring on the lower extremity in an 83-year-old woman is reported. A brief review of the clinical characteristics of this tumor as well as its immunohistochemical and ultrastructural features are presented.

Letterer-Siwe disease in an adult.

Letterer-Siwe disease, a proliferative disorder of Langerhans' cells, usually affects children during the first year of life. A 67-year-old woman is described here whose initial manifestation was a characteristic skin eruption. The clinical, pathologic, and ultrastructural features of Letterer-Siwe disease are reviewed and their role in diagnosis discussed.

Primary lymphocutaneous Nocardia brasiliensis infection.

We report a rare case of primary lymphocutaneous Nocardia brasiliensis infection occurring in an elderly diabetic man maintained on long-term therapy with prednisone. The mode of inoculation was that of a puncture wound caused by a contaminated needle that occurred one month prior to the development of the clinically apparent infection. The course of this patient's infection was protracted and required two surgical procedures and several months of antibiotic therapy. A review of 15 previously reported cases is presented as well as a discussion of appropriate medical therapy.

Familial aggregation of melanoma, basal cell carcinoma, and gastric adenocarcinoma.

A family with four cases of melanoma, seven cases of basal cell carcinoma, and two cases of gastric adenocarcinoma, is described. The proband, who had three different primary tumors, died of gastric cancer, as did his father. Four of the proband's six siblings were affected with melanoma or basal cell cancer, as were two of his three children. Both daughters of one melanoma patient developed basal cell cancers. No spouses were affected, the cases were widely separated in time and place, and no unusual exposures were reported. HLA analysis of affected and unaffected first-degree relatives showed no association with antigens previously described in familial melanoma or segregation with a specific HLA haplotype. Although there was no association with HLA phenotype, these results suggest that melanoma, basal cell carcinoma, and gastric adenocarcinoma can be inherited in an autosomally dominant pattern similar to other familial tumor syndromes.