PubMed Health⌕ Search

Biomedical subjects

J Vissers

Publications and source records attributed to J Vissers.

3 recordsLinked to original sources

Comparative genomic hybridization for cytogenetic evaluation of stillbirth.

OBJECTIVE: To ascertain the feasibility and reliability of comparative genomic hybridization for cytogenetic evaluation of macerated stillbirths. MATERIALS: We examined ten stillborn fetuses above 15 weeks' gestation whose karyotypes were unknown because of tissue culture failure. Sixteen fetuses that were successfully karyotyped using prenatal or postnatal tissues were also examined as controls, including five pregnancy terminations with autosomal aneuploidy, one with sex chromosome aneuploidy, one with a chromosomal deletion; five macerated fetuses with normal karyotypes, three with autosomal aneuploidy, and one with sex chromosome aneuploidy and discrepancy between chorionic villi and fetus. RESULTS: All comparative genomic hybridization analyses in fresh and macerated tissues were successful except for one. All normal karyotypes and aneuploidies were confirmed. Comparative genomic hybridization failed in one fetus with a deletion of the short arm of chromosome 18. In the stillborn fetuses without known karyotypes, one aberrant profile was found; however, the results were not confirmed with interphase fluorescence in situ hybridization. In one fetus triploidy was diagnosed with DNA flow cytometry. CONCLUSION: Comparative genomic hybridization is a valuable backup technique for aneuploidy screening in tissues from macerated stillborn fetuses when tissue culture fails. Gains or losses can subsequently be confirmed by fluorescence in situ hybridization, using DNA probes that focus on specific loci of a chromosome.

Aneuploidy↗

Selecting a suitable appointment system in an outpatient setting.

One of the principal causes of waiting time in outpatient departments is the lack of well-designed appointment systems. A conceptual framework is given for dealing with existing appointment systems and to explain their working. The variables that play a role with respect to the appointment system are discussed. All different appointment systems can be compared according to their effect on the patients' waiting time and the physician's idle time, when the systems are expressed in terms of a new variable called "prepunctuality." Prepunctuality means the difference between the time of a patient's arrival at the clinic and the expected time of treatment, and is caused by the patient's own earliness, physician's lateness and the earliness induced by the appointment system chosen. The relationship between prepunctuality and both waiting and idle time was investigated by means of a computer simulation model. In this way, the consequences of using different appointment systems have been clarified, expressed in mean waiting time for the patient and total idle time for the physician. Given certain standards for waiting and idle time, the calculated results can be used to determine an appropriate appointment system and the corresponding waiting and idle time for the range of most common clinic situations. Examples are given to illustrate how these results can be used.

Ambulatory Care Facilities↗