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We generalize the total variation restoration model, introduced by Rudin, Osher, and Fatemi in 1992, to matrix-valued data, in particular, to diffusion tensor images (DTIs). Our model is a natural extension of the color total variation model proposed by Blomgren and Chan in 1998. We treat the diffusion matrix D implicitly as the product D = LL(T), and work with the elements of L as variables, instead of working directly on the elements of D. This ensures positive definiteness of the tensor during the regularization flow, which is essential when regularizing DTI. We perform numerical experiments on both synthetical data and 3D human brain DTI, and measure the quantitative behavior of the proposed model.

This paper presents several models for investigating whether the HLA allogenotypes DR1/Br, DR3 and DR10 are genetic markers for a predisposition of experiencing unexplained recurrent foetal losses. A total of 199 women from 113 families answered questionnaires concerning their pregnancies and 145 of these women were HLA typed. The analysis of the data is complicated as dependencies between pregnancy outcomes are expected. The main purpose of the paper is to illustrate how such analyses can be performed using Bayesian graphical models and Gibbs sampling. The analyses are made using the programs BUGS and CODA. Markov chain Monte Carlo analyses within a Bayesian framework have become easier with the introduction of these programs. However, experience shows that some caution is required so we recommend making some initial analyses using very simple models and perhaps approximative methods, followed by a model development introducing increasing complexity., (Copyright 2000 John Wiley & Sons, Ltd.)

Objective: To investigate whether active immunization with third party leukocytes improves pregnancy outcome in women with unexplained recurrent miscarriages., Design: A double-blind prospective placebo-randomized trial., Patients: Sixty-six patients with unexplained recurrent miscarriages achieved pregnancy after having received active immunization or placebo., Interventions: Among the patients who achieved pregnancy, 43 were immunized with third party leukocytes and 23 received autologous leukocytes., Main Outcome Measures: Frequency of new miscarriages in actively immunized women compared with placebo., Results: In the total group of patients, 71% of the actively immunized patients had a successful pregnancy compared with 48% of the placebo treated patients (not significant, RR = 0.6; 95% confidence limits = 0.3-1.1). In a subgroup of patients with primary recurrent miscarriages the success rate was 76% compared with 38% in the placebo group (p < 0.02, RR = 0.4; 95% confidence limits = 0.2-0.9). In this subset of patients, median birthweight was also significantly higher in actively immunized patients than in placebo treated patients (3445 g versus 3000 g; p < 0.05)., Conclusions: Active immunization did not provide any benefit in the overall group of women with recurrent miscarriages. However, among women with primary recurrent miscarriages it may improve outcome with respect to the number of livebirths and birthweight.

Pregnancy outcome was investigated: 1) in fifteen women suffering from idiopathic recurrent spontaneous abortion (RSA) and who had experienced pregnancies with two different partners, and 2) in the mothers, the sisters and wives of the brothers of 90 consecutively referred women with RSA. After adjusting for ascertainment bias, the patients with 2 partners had an abortion rate of 72% with the first spouse (significantly increased compared with the expected rate) and a nearly 100% abortion rate with the second spouse. This suggests that, in the main, RSA is not partner-specific. The sisters of the patients had suffered a significantly increased miscarriage rate (25.3%) compared with the observed rate in a Danish control group. The wives of the brothers had an abortion rate of 18.8%, which was not significantly increased vis-à-vis the controls. The sisters showed a lifetime incidence of RSA (10.6%) which was significantly greater than comparable estimates in the literature. These results suggest the existence of a familial predisposition to spontaneous abortion in families where RSA occurs.

85 women undergoing vacuum aspiration following miscarriage were studied. At the time of vacuum aspiration, immunofluorescent stainings for detection of C. trachomatis proved positive in 5.9% of the patients. Group B streptococci were isolated in 7.5%, coliforms in 3.5%, and Gardnerella vaginalis in 51% of the patients. The overall frequency of postabortal pelvic inflammatory disease (PID) was 3.5%, whereas 40% of chlamydia-positive women contracted postabortal PID (p less than 0.05). No significant relation between other microorganisms and postabortal PID was observed. The duration of postabortal bleeding was unrelated to the genital microbiologic flora. Based on anamnestic information about previous pregnancies and duration of preoperative bleeding it was possible to define subgroups at risk of harboring C. trachomatis and coliforms. The clinical significance of this is unknown.

In a study of the etiology of idiopathic habitual abortion, we have found 2 patients with a history of 5 and 4 spontaneous abortions respectively, possibly caused by autoimmune abnormalities. In the plasma of one of the patients we had found the presence of lupus anticoagulans and other lupus antibodies, whereas the other suffered from a latent autoimmune hepatitis. We describe the successful treatment of the 2 womens' subsequent pregnancies with subcutaneous heparin supplemented with acetylsalicylic acid.