Isolation and characterization of human and rabbit sperm tail fibrous sheath

Using mechanical and chemical dissection methods, fibrous sheath was isolated both from normal ejaculated human spermatozoa and from rabbit cauda epididymal spermatozoa. The same techniques did not produce a pure preparation of fibrous sheath from ejaculated rabbit spermatozoa, suggesting that further cross-linking and stabilization of sperm structures occurs in response to components of the seminal plasma. The isolation procedures were monitored by phase contrast microscopy and the purity of the fibrous sheath was verified by electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human fibrous sheath revealed at least 14 protein bands of which the most intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5 kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid composition of the purified fibrous sheath from human and rabbit spermatozoa was similar, being high in aspartic acid and/or asparagine and glutamic acid and/or glutamine, serine, alanine, leucine, lysine and glycine, but low in histidine, tyrosine and isoleucine. This composition is similar to that reported for the rat and suggests that mammalian sperm tail fibrous sheaths are composed of similar types of proteins, although there are apparent differences in protein components between species.      

Gene-based strategies for the immunotherapy of cancer

 T lymphocytes play a crucial role in the host’s immune response to cancer. Although there is ample evidence for the presence of tumor-associated antigens on a variety of tumors, they are seemingly unable to elicit an adequate antitumor immune response. Modern cancer immunotherapies are therefore designed to induce or enhance T cell reactivity against tumor antigens. Vaccines consisting of tumor cells transduced with cytokine genes in order to enhance their immunogenicity have been intensely investigated in the past decade and are currently being tested in clinical trials. With the development of novel gene transfer technologies it has now become possible to transfer cytokine genes directly into tumors in vivo. The identification of genes encoding tumor-associated antigens and their peptide products which are recognized by cytotoxic T lymphocytes in the context of major histocompatibility complex class I molecules has allowed development of DNA-based vaccines against defined tumor antigens. Recombinant viral vectors expressing model tumor antigens have shown promising results in experimental models. This has led to clinical trials with replication-defective adenoviruses encoding melanoma-associated antigens for the treatment of patients with melanoma. An attractive alternative concept is the use of plasmid DNA, which can elicit both humoral and cellular immune responses following injection into muscle or skin. New insights into the molecular biology of antigen processing and presentation have revealed the importance of dendritic cells for the induction of primary antigen-specific T cell responses. Considerable clinical interest has arisen to employ dendritic cells as a vehicle to induce tumor antigen-specific immunity. Advances in culture techniques have allowed the generation of large numbers of immunostimulatory dendritic cells in vitro from precursor populations derived from blood or bone marrow. Experimental immunotherapies which now transfer genes encoding tumor-associated antigens or cytokines directly into professional antigen-presenting cells such as dendritic cells are under evaluation in preclinical studies at many centers. Gene therapy strategies such as in vivo cytokine gene transfer directly into tumors as well as the introduction of genes encoding tumor-associated antigens into antigen-presenting cells hold considerable promise for the treatment of patients with cancer. Received: 20 January 1997 / Accepted: 17 February 1997     

Elastin point mutations cause an obstructive vascular disease, supravalvular aortic stenosis

Supravalvular aortic stenosis (SVAS) is an inherited obstructive vascular disease that affects the aorta, carotid, coronary and pulmonary arteries. Previous molecular genetic data have led to the hypothesis that SVAS results from mutations in the elastin gene, ELN. In these studies, the disease phenotype was linked to gross DNA rearrangements (35 and 85 kb deletions and a translocation) in three SVAS families. However, gross rearrangements of ELN have not been identified in most cases of autosomal dominant SVAS. To define the spectrum of ELN mutations responsible for this disorder, we refined the genomic structure of human ELN and used this information in mutational analyses. ELN point mutations co-segregate with the disease in four familial cases and are associated with SVAS in three sporadic cases. Two of the mutations are nonsense, one is a single base pair deletion and four are splice site mutations. In one sporadic case, the mutation arose de novo. These data demonstrate that point mutations of ELN cause autosomal dominant SVAS.      

Balancing high accrual and ethical recruitment in paediatric oncology: a qualitative study of the 'look and feel' of clinical trial discussions

Background  

High accrual to clinical trials enables new treatment strategies to be tested rapidly, accurately and with generalisability. Ethical standards also must be high so that participation is voluntary and informed. However, this can be difficult to achieve in trials with complex designs and in those which are closely embedded in clinical practice. Optimal recruitment requires a balance of both ethical and accrual considerations. In the context of a trial of stratified treatments for children with acute lymphoblastic leukaemia (UKALL2003) we examined how recruitment looked to an observer and how it felt to the parents, to identify how doctors' communication could promote or inhibit optimal recruitment.     

Daily rhythm of vigilance assessed by temporal resolution of the visual system

To assess the daily distribution of temporal resolution in visual detection, binocular double-pulse resolution (DPR) was measured over a 24 h period in six healthy subjects. DPR showed a significant daily variation with an amplitude for the foveal stimulus of up to 60%. Like in other vigilance-dependent daily rhythms, optimal performance occurred around midday. The DPR measurements described here are an excellent method for assessment of vigilance and mental alertness (e.g. in pharmacological studies). They show strong time-of-day differences, are highly reliable across successive measurements, and can be fully automated.     

Intra-arterial chemotherapy with methotrexate and 5-fluorouracil in extensive locoregional recurrences of cervix cancer

The significance of intra-arterial cytostatic drug infusion in connection with histologically confirmed recurrences of squamous carcinomas was investigated within a clinical controlled trial between 1978 and 1985. Patients selection according to strict precaution in consideration of the factors influencing prognosis. After clinical examination, computer-tomographic, sono- and angiographic staging ten patients received MTX and 5FU i.a., completed by intra-venous CMFV-treatment in cases with objective remission of disease (therapy arm A). Six women received FACV-combination only systemically (therapy arm B). One partial (PR) and fife moderate remissions (MR) were achieved by intra-arterial chemotherapy in early time. The median duration of survival was 7.5 month for patients in therapy arm A. Significant prolongation of cumulative survival time (p less than 0.05) was determined only by remission of disease in patients with grade performance status 0-1 WHO. Intra-arterial chemotherapy showed lower toxicity versus systemic FACV- or CMFV-treatment. No complications of using prolonged i.a. infusion by Seldinger's technique were encountered. Further studies for within interdisciplinary scientific research in more chemosensitive malignancies of the female genital tract are warranted.     

Course of pregnancy and labor following cytostatic treatment of trophoblastic tumors

In our department 24 patients underwent treatment of invasive trophoblastic tumours from 1975 to 1984. In 13 cases we were dealing with invasive bladder moles and in 11 cases with chorionic carcinoma. Nine women became pregnant, among them one case of chorionic carcinoma. Eight women were delivered of a viable child on average 30 months after the end of the treatment, whereas one patient wanted termination of pregnancy. Six women had undergone a methotrexate monotherapy before, two women a sequential treatment with methotrexate + actinomycine D. The undisturbed pregnancies and births of eight healthy babies point to an unimpaired fertility after chemotherapy of trophoblastic tumours.     

Dispensary program in cytostatic long-term therapy of gynecologic malignancies

The growing importance of medical malignancy treatment leads to a quick increase of the number of cases which need treatment by cytotoxic drugs. This necessitates comprehensive follow-up care programs coping both with medical and individual requirements of patients. Long-term-chemotherapy requires intensive control and well-organized oncological, psychical and social care. These functions may be realized by oncological centres only by way of effective interdisciplinary co-operation incorporating regional health-service facilities. The model of care, elaborated in 1974 in the Gynecological Clinic of the Medical Academy Dresden, represents a close connection between in-patient intensive diagnostics and therapy and specialized predominantly out-patient long-term-therapy. The program of follow-up care introduced takes into account the efforts for greater therapeutical security, improvement of the quality of life and social rehabilitation.