Faculty Bibliography

BACKGROUND: Osseous metaplasia of the endometrium is a rare disorder and can be associated with infertility. Although successful diagnosis and treatment have been widely reported, correct diagnosis in many cases still represents a challenge. CASE: A 40-year-old woman complaining of infertility presented with a diagnosis of retained intrauterine device (IUD) on ultrasound. Hysteroscopy revealed a normal endometrial cavity, but no IUD was visualized. Curettage pathology specimens showed chronic endometritis and calcification. Repeat hysteroscopy was performed because of persistent echogenic foci in the endometrium on follow-up ultrasound. Several irregular and calcified plaques were successfully removed. CONCLUSION: Osseous metaplasia can be misdiagnosed because of its rare incidence. Physicians should be aware of osseous metaplasia in the differential diagnosis of patients with uncertain history who present with a sonographic image resembling an IUD

Tumor necrosis factor (TNF) is a prototypic proinflammatory cytokine that contributes significantly to the development of immunopathology in various disease states. A complication of TNF blockade therapy, which is used increasingly for the treatment of chronic inflammatory diseases, is the reactivation of latent tuberculosis. This study used a low-dose aerogenic model of murine tuberculosis to analyze the effect of TNF neutralization on disease progression in mice with chronic tuberculous infections. Histological, immunohistochemical, and flow cytometric analyses of Mycobacterium tuberculosis-infected lung tissues revealed that the neutralization of TNF results in marked disorganization of the tuberculous granuloma, as demonstrated by the dissolution of the previously described B-cell-macrophage unit in granulomatous tissues as well as by increased inflammatory cell infiltration. Quantitative gene expression studies using laser capture microdissected granulomatous lung tissues revealed that TNF blockade in mice chronically infected with M. tuberculosis leads to the enhanced expression of specific proinflammatory molecules. Collectively, these studies have provided evidence suggesting that in the chronic phase of M. tuberculosis infection, TNF is essential for maintaining the structure of the tuberculous granuloma and may regulate the granulomatous response by exerting an anti-inflammatory effect through modulation of the expression of proinflammatory mediators

The granulomatous reaction is the hallmark of the host response to infection with Mycobacterium tuberculosis. Despite its apparent importance to host defence against the tubercle bacillus, the granulomatous response remains to be completely defined. The present study used histological, immunohistochemical and flow-cytometric analyses to characterize pulmonic granulomatous tissues of tuberculous mice and humans. The kinetics of recruitment of neutrophils, macrophages, dendritic cells, and T and B lymphocytes into the lungs of mice infected aerogenically with the virulent Erdman strain of M. tuberculosis was evaluated in detail in both the acute and persistent phase of infection. A hypoxia-sensing compound based on the 2-nitroimidazole structure (EF5), together with immunohistochemical studies targeting endothelial cells were used to examine the relative oxygen tension in tuberculous granulomatous tissues in mice. The results have provided evidence that: (i) the granulomatous tissues are a highly organized structure whose formation is regulated by orderly recruitment of specific immune cells exhibiting distinct spatial relationship with one another; (ii) the granulomatous reaction, at least in the mouse, may represent an exaggerated response to the tubercle bacillus that can play a role in the development of immunopathology; (iii) B lymphoid aggregates are a prominent feature in both murine and human granulomatous tissues, although the immune cells that are most prominently associated with these clusters vary among the two species; (iv) murine tuberculous granulomatous tissues are relatively aerobic, suggesting that mouse models of persistent tuberculosis may not be suitable for the study of any hypoxic response of M. tuberculosis

Although great progress has been made in both the investigation and treatment of infertility, a considerable number of patients still fail to conceive. Spermatogenic failure and/or oocyte ageing appear to be responsible for a large proportion of cases. The use of donor gametes may bring legal, ethical and even social problems of acceptance that can discourage infertile couples from the donor route. Fortunately, emerging reproductive technologies and preliminary results from animal experiments provide some hope for alternative sources of gametes through which these infertile patients can finally conceive their own genetic child. In conjunction with intracytoplasmic sperm injection (ICSI), fertilization of human oocytes with immature sperm precursors, e.g. spermatids and even secondary spermatocytes, has resulted in healthy babies. Pregnancies have also resulted from the use of spermatids derived from in-vitro spermatogenesis. In the mouse, even primary spermatocytes appear able to participate in normal embryogenesis. In view of the possibility for transplantation and even xenotransplantation of spermatogonia to a host testis in animals, a similar use of human male stem cells might provide an attractive source for the treatment of males with arrested spermatogenesis, as well as male cancer patients. Transplantation of somatic cell nuclei and their haploidization within oocytes may prove to be a practical way of eradicating age-related aneuploidy and so constitute an innovative source of healthy oocytes. Most importantly, however, the safety of the procedures described here needs to be proven before their application to the human arena. Finally, we discuss the implications of cytoplasmic quality and of genetic imprinting in the context of these manipulations

In the last 3 years, several studies have shown that xenogeneic transplantation of rodent spermatogonia is feasible. The treatment of infertile patients with spermatogenic arrest using the injection of immature germ cells has yielded only poor results. We attempted to establish a complete spermatogenetic line in the testes of mutant aspermatogenic (W/Wv) and severe combined immunodeficient mice (SCID) transplanted with germ cells from azoospermic men. Spermatogenic cells were obtained from testicular biopsy specimens of men (average age of 34.3 +/- 9 years) undergoing infertility treatment because of obstructive and non-obstructive azoospermia. Testicular tissue was digested with collagenase to promote separation of individual spermatogenic cells. The germ cells were injected into mouse testicular seminiferous tubules using a microneedle (40 microm inner diameter) on a 10 ml syringe. To assess the penetration of the cell suspension into the tubules, trypan blue was used as an indicator. Mice were maintained for 50 to 150 days to allow time for germ cell colonisation and development prior to them being killed. Testes were then fixed for histological examination and approximately 100 cross-sectioned tubules were examined for human spermatogenic cells. A total of 26 testicular cell samples, 16 frozen and 10 fresh, were obtained from 24 men. The origin of the azoospermia was obstructive (OA) in 16 patients and non-obstructive (NOA) in 8 patients. The concentration of spermatogenic cells in the OA group was 6.6 x 10(6) cells/ml, and 1.3 x 10(6) cells/ml in the NOA group (p < 0.01). The different spermatogenic cell types were distributed equally in the OA samples, ranging from spermatogenia to fully developed spermatozoa, but in the NOA group the majority of cells were spermatogonia and spermatocytes. A total of 23 testes from 14 W/Wv mice and 24 testes from 12 SCID mice were injected successfully, as judged by the presence of spermatogenic cells in histological sections of testes removed immediately after the injection. However, sections from the remaining testes examined up to 150 days after injection showed tubules lined with Sertoli cells and xenogeneic germ cells were not found. The reason why the two strains of mouse used as recipients did not allow the implantation of human germ cells is probably due to interspecies specificity involving non-compatible cell adhesion molecules and/or immunological rejection

OBJECTIVE: To evaluate the incidence of sperm aneuploidy in men screened for infertility and identify any eventual relation with assisted reproductive outcome. DESIGN: Controlled prospective study. SETTING: University hospital-based IVF program. PATIENT(S): Infertile couples who were screened for sperm aneuploidy and evaluated for IVF treatment. INTERVENTION(S): Fluorescence in situ hybridization was used to identify chromosomes 18, 21, X, and Y. The assisted reproductive techniques of IVF and intracytoplasmic sperm injection were used for infertility treatment. MAIN OUTCOME MEASURE(S): The incidence of sperm aneuploidy, semen parameters, fertilization rate, pregnancy characteristics, and rate of neonatal malformations were determined. RESULT(S): Oligozoospermic and teratozoospermic men had a significantly higher incidence of chromosomal abnormalities than men with normal semen parameters (2.7% vs. 1.8%). The increased frequency of sperm aneuploidy did not appear to affect pregnancy losses or the occurrence of neonatal malformations. CONCLUSION(S): Suboptimal semen samples had a higher incidence of aneuploidy. In this study, the increased frequency of chromosomal abnormalities did not have a direct effect on the fertilization rate, pregnancy characteristics, or neonatal outcome