The stumptailed macaque as a model for androgenetic alopecia: Effects of topical minoxidil analyzed by use of the folliculogram

The use of the stumptailed macaque, which possesses hereditary balding characteristics similar in many respects to that of androgenetic alopecia in humans, enables us to obtain a morphometric assessment of the rate of cyclic change of the hair follicle. The analysis of folliculograms results in data that can determine the rate of cyclic progression (resting to regrowing phase, and regrowing to late anagen phase) and the overall change in follicular size. Topical minoxidil apparently activates the resting follicles in the bald scalp and stimulates their cyclic progression. It also increases DNA synthesis, resulting in relative enlargement of the growing anagen follicles. All minoxidil-treated animals had hair regrowth, although in varying degrees of restoration to the prebald condition and after varying durations of treatment. In general, the response was greater in the younger, early-bald stumptailed macaques compared with the older, advancedbald animals. The degree of response varied from regrowth of thicker, darker hairs over the entire bald area, with folliculograms showing corresponding large proportions of late anagen follicles, to the arresting of the balding process, with folliculograms showing maintenance of moderate populations of anagen follicles. Cessation of topical minoxidil treatment resulted in a renewal of the balding process, with folliculograms demonstrating increases in the proportion of resting follicles. This withdrawal from treatment apparently had no effect on hair regrowth during subsequent reapplications of minoxidil. Such treatment resulted in regrowth similar to that in the first treatment phase. Continuous treatment of topical minoxidil for 4 years has not resulted in systemic or local side effects in these animals.     

Attitudes toward an unsolicited approach in relation to status of genetic disease: Exemplified by α1‐antitrypsin deficiency

Knowledge of a genetic disease in an individual raises the questions of whether and how this information should be communicated to his or her family. The aim of the present study was to provide factual information about attitudes towards an unsolicited approach from a physician regarding genetic counseling within affected families. We performed a questionnaire study among patients with α₁‐antitrypsin deficiency, their examined and unexamined relatives, and a control group of Danish citizens. Of 2,146 subjects, the questionnaires were returned by 1,761 (82%), and 1,609 (75%) wanted to participate. Stepwise logistic regression showed that phenotype/subgroup, having descendants, and being female were significantly related to the approval of an unsolicited approach and the informing of relatives. Provided it was difficult for the index case to inform relatives about their risk and about his/her disease, then a total of 75.8% would not proscribe an unsolicited approach by the physician. Most of those for proscribing an unsolicited approach found that relatives should be informed in advance by the index case. The control group of randomly chosen Danes was the most skeptical towards an unsolicited approach. Most individuals found that genetic risk information should be shared with relatives at‐risk. A flexible information policy by the health care system based on active approach towards relatives is acceptable to 75 to 95% of individuals in order to ensure diffusion of genetic risk information within families segregating for a genetic disease with a modifiable outcome. Am. J. Med. Genet. 94:207–213, 2000. © 2000 Wiley‐Liss, Inc.     

Human T-lymphotropic virus (HTLV) types I and II infection in sexual contacts and family members of blood donors who are seropositive for HTLV type I or II. American Red Cross HTLV-I/II Collaborative Study Group

Interviews and laboratory testing were conducted for 168 contacts referred by former blood donors identified as seropositive for antibody to human T-lymphotropic virus type I (HTLV-I) or type II (HTLV-II). Thirty-two (28%) of 114 heterosexual contacts of seropositive donors, including 12 women and 20 men, were found to be antibody positive. None of 40 offspring (except one adult man who reported sexual contact in Puerto Rico) or 14 other (nonspousal) family members were seropositive. Thirty-one of the seropositive contacts were typeable as having either HTLV-I (52%) or HTLV-II (48%). Assessment of couples found that the median duration of the sexual relationship was significantly longer (p = 0.03) for those in which both partners were infected than in discordant pairs. Analysis of risk history data for 22 infected couples revealed that, in three cases, risk factors (Japanese ancestry or sexual contact with an injecting drug user) could be identified in the women, but not in their male partners. Among couples in which the male had the greater risk history, the risk factor was either a history of transfusion, birth or sexual exposure in an endemic area, or injected drug use. Counseling strategies for individuals with HTLV-I or HTLV-II infection should take into account the relatively high seroprevalence in their partners and should address the potential for sexual transmission in both directions.     

Computer-aided design of facial prostheses by means of 3D-data acquisition and following symmetry analysis

The aim of this study was to investigate whether a method of designing digital models of facial prostheses was suitable for patients with orbital defects. 32 patients were included in a retrospective study. 23 of them already had a facial prosthesis. 3D-data of the faces were acquired optically using fringe projection technique without and with (if available) the facial prosthesis in place. The healthy side of the surface models was mirrored to reconstruct the defect area. By generating a NURBS-model, the edges of the virtual prostheses were adapted to the defect region. The CAD models were stored in STL format as templates for facial prostheses. Using an automatically calculated asymmetry index (AI), four situations of the digitized facial surface were analysed for symmetry: 1. with defect area excluded, 2. with mirrored healthy surface, 3. with digital CAD template, and 4. with manually produced facial prosthesis inserted (if available). Mean AI values were 6.05 ± 3.26 (situation 1), 4.79 ± 2.51 (situation 2), 5.12 ± 2.61 (situation), and 6.74 ± 2.77 (situation 4). Additionally, the CAD templates were rated by three anaplastologists. Ratings did not differ significantly. They partially agreed with the three statements “The CAD prosthesis fits harmoniously within the face”, “The CAD prosthesis could be used for a wax pattern during conventional fabrication” and “The CAD prosthesis and the wax pattern reduce workload”. The results indicate that the presented technique has the potential to increase facial symmetry and facilitate the technical procedure. However, symmetry alone is not a sufficient criterion for design of a facial prosthesis.     

3D printed simulation models based on real patient situations for hands‐on practice

During the last few years, the curriculum of many dentistry schools in Germany has been reorganised. Two key aspects of the applied changes are the integration of up‐to‐date teaching methods and the promotion of interdisciplinarity. To support these efforts, an approach to fabricating individualised simulation models for hands‐on courses employing 3D printing is presented. The models are based on real patients, thus providing students a more realistic preparation for real clinical situations. As a wide variety of dental procedures can be implemented, the simulation models can also contribute to a more interdisciplinary dental education. The data used for the construction of the models were acquired by 3D surface scanning. The data were further processed with 3D modelling software. Afterwards, the models were fabricated by 3D printing with the PolyJet technique. Three models serve as examples: a prosthodontic model for training veneer preparation, a conservative model for practicing dental bonding and an interdisciplinary model featuring carious teeth and an insufficient crown. The third model was evaluated in a hands‐on course with 22 fourth‐year dental students. The students answered a questionnaire and gave their personal opinion. Whilst the concept of the model received very positive feedback, some aspects of the implementation were criticised. We discuss these observations and suggest ways for further improvement.