Oscillations of Drops with Mobile Contact Lines on the International Space Station: Elucidation of Terrestrial Inertial Droplet Spreading.

We analyze shape oscillations of sessile water drops with fully mobile contact lines (CL) aboard the International Space Station. The unique microgravity environment enables the study of centimeter-sized droplets with associated inertial-capillary motions. Plane-normal substrate vibrations induce resonance behaviors quantified by frequency scans from which the natural frequencies and mode shapes are identified for nine different hydrophobic surfaces. Experimental observations agree well with, and validate, a recent spectral prediction of mobile CL sessile drop oscillations. The experimental findings help elucidate terrestrial droplet inertial spreading, a poorly understood phenomenon pervasive in many processes.

Finite-amplitude dynamics of coupled cylindrical menisci.

The cylindrical meniscus is a liquid/gas interface of circular-cap cross-section constrained along its axis and bounded by end-planes. The inviscid motions of coupled cylindrical menisci are studied here. Motions result from the competition between inertia and surface tension forces. Restriction to shapes that are of circular-cap cross-section leads to an ordinary differential equation (ode) model, with the advantage that finite-amplitude stability can be examined. The second-order nonlinear ode model has a Hamiltonian structure, showing dynamical behavior like the Duffing-oscillator. The energy landscape has either a single- or double-welled potential depending on the extent of volume overfill. Total liquid volume is a bifurcation parameter, as in the corresponding problem for coupled spherical-cap droplets. Unlike the spherical-cap problem, however, axial disturbances can also destabilize, depending on overfill. For large volumes, previously known axial stability results are applied to find the limit at which axial symmetry is lost and comparison is made to the Plateau-Rayleigh limit.

Palmar papillomatous lesions reminiscent of epidermal nevus in a case of focal dermal hypoplasia: a nosological consideration.

A 40-year-old woman with focal dermal hypoplasia had a palmar papillomatous lesion showing a linear arrangement and histopathological features compatible with a diagnosis of epidermal nevus. This unusual manifestation of focal dermal hypoplasia is difficult to categorize. Undoubtedly the lesion reflects functional X-chromosome mosaicism. Although the mechanism of lyonization may give rise to true epidermal nevi such as CHILD nevus, we prefer to classify the present skin lesion as a nevoid disorder and not as an epidermal nevus.

Topical immunotherapy of alopecia areata.

Topical immunotherapy has proven to be a highly rewarding treatment modality for extensive forms of AA. The method should be considered at this time to be in an experimental stage, and therefore hesitation to adopt it is understandable. However, other acceptable and effective modes of treatment are thus far lacking. Extensive AA is not merely a cosmetic problem. Affected individuals often experience a considerable subjective loss of quality of life, and in such cases topical immunotherapy should be considered.

Epidermal proliferation and keratinization following standardized elicitation with diphenylcyclopropenone.

Diphenylcyclopropenone (DCP) was applied to the upper arms of five alopecia areata patients using 10% of the concentration that had been applied previously to the scalp during topical immunotherapy. DCP applied in this concentration evoked a mild eczematous reaction. Biopsies were taken before DCP application and after 24, 48 and 96 h. A large increase in T-lymphocytes and CD14-positive cells in the dermis was seen after 24 h. Migration of these cells into the epidermis was mainly observed during the first 48 h. This was followed by epidermal proliferation as assessed by the number of Ki-67-positive nuclei and the degree of Ks8.12-binding. Both showed their main increase after 48 h; but after 24 h the increase of Ki-67-positive nuclei was significant (P < 0.04). Involucrin and filaggrin showed a gradual increase which became substantial after 96 h (both P < 0.04). As the invasion of inflammatory cells into the epidermis preceded the main increase in epidermal proliferation, cytokines are suggested as possible mediators for the initial phase of the proliferative response after DCP application.

Topical immunotherapy for alopecia areata: re-evaluation of 139 cases after an additional follow-up period of 19 months.

Within a group of 139 patients previously studied during treatment for alopecia areata with diphenylcyclopropenone (DCP), hair growth was re-evaluated after a period of 19 months following completion of our previous study. Fifty-four patients treated with DCP had total and 6 had partial but cosmetically acceptable regrowth. Twenty-five patients with total regrowth had stopped DCP treatment for a mean period of 15 months and had not relapsed. Nineteen of 28 patients who still applied DCP were in the process of stepwise discontinuation of treatment. Fifteen patients had subsequently been treated with squaric acid dibutylester (SADBE) after having acquired 'tolerance' to DCP; at the time of re-evaluation 3 of these patients had complete regrowth, and 4 patients had partial but cosmetically acceptable regrowth. Topical immunotherapy with DCP and SADBE had resulted in total regrowth in 57/139 patients (41.0%) and in partial but cosmetically satisfactory regrowth in 10/139 patients (7.2%). The type of involvement and duration of alopecia areata were factors of prognostic significance.

Prognostic factors in the treatment of alopecia areata with diphenylcyclopropenone.

One hundred thirty-nine patients with alopecia areata were treated with diphenylcyclopropenone. Before treatment, 85 patients had subtotal or total hair loss (greater than 90% bald area) and in the remaining patients scalp involvement was between 40% and 90%. The following three factors were found to be of prognostic significance: type of alopecia areata as documented before treatment, duration of the disease before therapy, and presence of nail changes. Other factors such as age at onset, sex, presence of atopic features, the extent of variation in the range of diphenylcyclopropenone concentrations during treatment, and sleep disturbances caused by pruritus did not influence the prognosis significantly.

Treatment of alopecia areata with diphenylcyclopropenone.

One hundred thirty-nine patients with severe alopecia areata (the majority with the subtotal, total, or universalis type) were treated with topical immunotherapy (diphenylcyclopropenone). Patients were initially treated unilaterally; the other side of the scalp served as a control. In 50.4% of the patients the response was either excellent (total regrowth) or satisfactory (subtotal regrowth with only a few remaining bald patches). The most frequent side effects were eczematous reactions with blistering, spreading of the induced contact eczema, and sleep disturbances.

The captopril test in the detection of renovascular disease in hypertensive patients.

A number of reports share the conclusion that the captopril test is an adequate screening procedure for the detection of renovascular disease among hypertensive patients. Therefore, we prospectively studied the value of this test in 149 consecutive hypertensive patients. The test was considered positive if plasma renin activity, after an oral dose of 25 mg of captopril, rose by more then 4.44 ng.L-1.s-1 (16.0 ng/mL per hour). The sensitivity of the test was 39%, the specificity was 96%, the positive predictive value was 81%, and the negative predictive value was 79%. No clinically important cutoff point identifying patients with renal artery stenosis could be detected in the values of baseline and stimulated plasma renin activity nor in baseline blood pressure or changes after captopril testing. The low sensitivity makes the captopril test unfit to be used as a screening procedure in an unselected hypertensive population.