Notizen: Morphological and functional heterogeneity of the splenic macrophage (Mφ) population was studied in Leishmania donovani (LD) infected BALB/c mice. On a discontinuous percoll gradient two distinct Mφ populations were separated. They differed significantly in size as evident from Scanning Electron Microscopy (SEM). Morphologically, the bigger Mφ (LM) showed surface projections, whereas the smaller Mφ (SM) was round. As regards the antigen-presenting abilities, the LM of infected animals showed defective antigen-presenting abilities at a later stage of the disease, i.e. 6 months post infection (6I-LM) but not earlier, whereas the SM population remained functionally intact throughout the course of the infection. Further, the 6I-LM showed a much enhanced Ad status as compared to their controls. Interestingly, both the 6I-LM and the control set showed a comparable level of binding of a known Ad restricted peptide. Despite the presence of sufficient Ad molecules and the ability to bind the appropriate peptide, 6I-LM were unable to stimulate peptide specific T-cell hybridoma. Further, the 6I-LM showed an increase in membrane fluidity and distorted morphology with membrane fissure and blebs as evident from SEM. It is possible that an increase in the membrane fluidity may lead to the defective antigen-presenting ability of 6I-LM. Thus, the LD infection functionally keep the 6I-LM out of antigen presentation and this may contribute to the defective cell mediated immune response in leishmaniasis.

Notizen: The expression of chemokines and chemokine receptors was studied in Leishmania donovani (LD)-infected human mononuclear phagocytes and the human monocytic cell line THP1. Our studies showed that LD infection caused the upregulation of three β chemokines (macrophage inflammatory protein-1 alpha (MIP-1α), MIP-1β and RANTES (regulated on activation normal T cell expressed and secreted)), one α chemokine (interleukin-8 (IL-8)) and the CC chemokine receptor 5 (CCR5) but not CCR1, as evident from reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. The CCR5 upregulation in human mononuclear phagocytes and THP1 cells was also evident by confocal microscopy. The possible association of such upregulation in relation to Leishmania and human immunodeficiency virus (HIV) coinfection was discussed.

Notizen: Tetracyclines (TCN) were introduced in 1948 as broad-spectrum antibiotics that may be used in the treatment of many common infections in children and adults. One of the side-effects of tetracyclines is incorporation into tissues that are calcifying at the time of their administration. They have the ability to chelate calcium ions and to be incorporated into teeth, cartilage and bone, resulting in discoloration of both the primary and permanent dentitions. This permanent discoloration varies from yellow or gray to brown depending on the dose or the type of the drug received in relation to body weight. Minocycline hydrochloride, a semisynthetic derivative of tetracycline often used for the treatment of acne, has been shown to cause pigmentation of a variety of tissues including skin, thyroid, nails, sclera, teeth, conjunctiva and bone. Adult-onset tooth discoloration following long-term ingestion of tetracycline and minocycline has also been reported. The remarkable side-effect of minocycline on the oral cavity is the singular occurrence of “black bones”, “black or green roots” and blue-gray to gray hue darkening of the crowns of permanent teeth. The prevalence of tetracycline and minocycline staining is 3–6%. The mechanism of minocycline staining is still unknown. Most of the reviewed literature consisted of case reports; longitudinal clinical trials are necessary to provide more information on the prevalence, severity, etiology and clinical presentation of tetracycline and TCN-derivative staining in the adult population.

Notizen: Two experiments assessed the effect of current and elevated levels of ultravioletB (UV-B) radiation on forage crop production. The effect of current levels of UV-B radiation was assessed by comparing the growth of eight cultivars of four legume and four grass species for three growing seasons (1994–96) under simulated sward conditions in the field. An exclusion system using cellulose diacetate or polyester covers provided comparable growing conditions for the plants, except for the presence or absence of ambient UV-B radiation, respectively. The second experiment studied the effect of elevated levels of UV-B on eight cultivars of two legume and two grass species in the greenhouse under simulated sward conditions. Natural lighting with sufficient supplemental light was used to provide ideal growing conditions for a 16-h day length. Separate sets of UV lights were installed to provide UV-B levels at approximately the same intensity as would be found in mid summer, and 33% and 66% more than this value. A fourth treatment consisted of removing UV-B radiation by using a polyester filter. Plant production was measured in both experiments. In 1994, field herbage yields from all young grass and legume seedlings were not significantly affected by the exclusion of ambient UV-B radiation, with the exception of alfalfa. Intra-specific variations with alfalfa yields were found for reduced levels of UV-B radiation. In general, these trends persisted as stands matured during two post seeding years. In the second experiment, no significant differences were observed for all tested species with increasing levels of UV-B radiation, except with some alfalfa cultivars and one birdsfoot trefoil cultivar. Collectively, these results demonstrate that in the northern latitudes young and mature plants of the studied species are resistant to current and potentially higher levels of solar UV-B radiation, with the exception of some alfalfa cultivars. The yield of these cultivars increased under enhanced levels of UV-B radiation in the greenhouse and decreased when UV-B was excluded in the field.

Notizen: In November 1997, approximately 1 year before being evaluated at the Mayo Clinic, Rochester, a 63-year-old woman presented with erosive tongue lesions that were diagnosed by her physician as oral lichen planus. The lesions responded well to 3 months of treatment with systemic and topical corticosteroids and topical antiyeast medication. She stopped taking the medications and had a relapse. A few months after the oral lesions developed, her left eyelid became ptotic. Results of magnetic resonance imaging of her brain were normal, and the ptosis resolved spontaneously after 2 weeks. One year later, her right eyelid began to droop, and the results of edrophonium testing were positive. She was prescribed prednisone, 30 mg daily, and pyridostigmine, as needed. The ptosis improved, but never fully resolved. Radiography revealed a left ‘‘thyroid nodule,’' but computed tomography did not show a mediastinal mass. She was advised to have the ‘‘nodule’' removed surgically and came to the Mayo Clinic, Rochester, for a second opinion.Her medical history was significant for the following: tinnitus, glaucoma, early bilateral cataracts, and long-standing hypertension, for which she took losartan, 50 mg twice daily. Other medications included: prednisone, 30 mg daily; pyridostigmine as needed; famotidine, 40 mg daily; and eyedrops for glaucoma. She denied any history of hyperthyroidism or hypothyroidism, head and neck irradiation, family history of thyroid disease, or diplopia. Hepatitis serologic studies revealed hepatitis B exposure and recovery, hepatitis C immunity, and a previous hepatitis A viral infection.On examination at the Mayo Clinic, Rochester, an erosive hypertrophic plaque was noted on the posterior dorsal half of the tongue, and vesicles and erythematous erosions on the hard and soft palates ( 〈link href="#f2.1"〉Fig. 1a). A lace-like white pattern was seen on the buccal mucosa bilaterally, and a small erosive patch on the left buccal mucosa ( 〈link href="#f2.1b"〉Fig. 1b). Ocular and nasal mucous membranes were normal in appearance, and there were no pertinent skin findings. Dermatopathologic examination of an excisional biopsy specimen from the left dorsum of the tongue demonstrated an ulcer with epitheliomatous hyperplasia and a granulomatous reaction, presumably due to yeast infection. Silver staining showed hyphae and yeast at the base of the tongue ulcer. The results of the direct immunofluorescence study were negative and revealed no lichenoid changes on hematoxylin and eosin staining. Indirect immunofluorescence testing of the serum revealed a 1 : 80 titer of basement membrane zone antibodies, reflecting pemphigoid. This test was positive on repeat study. Salt-split skin on monkey esophagus revealed an epidermal pattern of basement membrane zone antibodies. Treatment included fluocinonide gel applied to the involved areas four times daily and oral antiyeast therapy (fluconazole, 200 mg once daily by mouth) while the rest of the evaluation was being completed.〈figure xml:id="f2.1"〉1(a)〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD035-2:IJD_035_2_f1a"/〉Erosive hypertrophic tongue plaque.〈figure xml:id="f2.1b"〉 (b)  〈mediaResource alt="image" href="urn:x-wiley:00119059:IJD035-2:IJD_035_2_f1b"/〉Erosive patch on the buccal mucosa.As part of the evaluation of the ptosis, a myasthenia gravis antibody panel was performed. It revealed the following abnormalities: striated muscle antibody at 1 : 480 (reference range, 〈1 : 60), acetylcholine receptor binding antibody at 6.33 nmol/L (reference range, ≤ 0.02 nmol/L), acetylcholine receptor blocking antibody at 31% (reference range, 0–25%), and acetylcholine receptor modulating antibody at 100% (reference range, 0–20%), suggesting thymoma. Treatment included pyridostigmine, 30–45 mg 3–4 times daily, to control the myasthenia symptoms, while the ill-defined neck mass was being evaluated.A mildly enlarged thyroid was noted on physical examination. Hematology panel revealed thyroid-stimulating hormone (TSH) levels in the low normal range; the thyroid microsomal antibody was normal. Chest radiography showed minor tracheal deviation, and a previous computed tomogram showed what appeared to be a 3-cm enlarged mass in the thyroid. Ultrasonographically guided thyroid biopsy did not show malignancy, but a benign mesenchymal-type tumor was found and surgical excision was planned. Intraoperatively, a thymoma of the left cervical thymic tongue was found.At 6 months' follow-up, the ptosis and oral mucosal lesions had improved significantly, although she continued topical corticosteroid therapy intermittently for minor erosive oral disease.