Search

Background. There are limited data on high-risk human papillomavirus (hr-HPV) genotypes among HIV-positive women in Africa, and little is known about their relationship with cervical cytology in these populations. Methods. We conducted a cross-sectional study among 194 HIV-positive women (143 from Tanzania, and 51 from South Africa) to evaluate HPV genotypes among HIV-positive women with normal and abnormal cytology. Cervical samples were genotyped for HPV types, and slides were evaluated for atypical squamous cell changes according to the Bethesda classification system. Results. Prevalence of high grade squamous intraepithelial dysplasia (HSIL) was 9%. Overall, more than half (56%) of women were infected with an hr-HPV type; 94% of women with HSIL (n=16), 90% of women with LSIL (n=35), and 42% of women within normal limits (WNL) (n=58) tested positive for hr-HPV. Overall, the most prevalent hr-HPV subtypes were HPV16 (26%) and HPV52 (30%). Regional differences in the prevalence of HPV18 and HPV35 were found. Conclusion. Regional differences in HPV genotypes among African women warrant the need to consider different monitoring programmes for cervical preneoplasia. HPV-based screening tests for cervical preneoplasia would be highly inefficient unless coupled with cytology screening of the HPV-positive sample, especially in HIV-positive women.

Objective: The objective was to examine the use of a tailor-made DNA microarray containing probes representing the vaginal microbiota to examine bacterial vaginosis. Study Design: One hundred one women attending a health center for HIV testing in South Africa were enrolled. Stained, liquid-based cytology slides were scored for bacterial vaginosis. An inventory of organisms was obtained using microarray technology, probing genera associated with bacterial vaginosis in more detail, namely Gardnerella, Atopobium, Dialister, Leptotrichia, Megasphaera, Mobiluncus, Peptostreptococcus, Prevotella, and Sneathia. Results: Of 101 women, 34 were diagnosed positive for bacterial vaginosis. This condition was associated with an increased microbial diversity. It is no longer useful to base the diagnosis of bacterial vaginosis on Gardnerella alone. Rather, its presence with Leptotrichia and Prevotella species, and especially Atopobium was more indicative of an aberrant state of the vaginal flora. Conclusion: To understand the vaginal microbiota in more detail, microarray-based identification can be used after microscopic scoring. © 2011 Mosby, Inc. All rights reserved.

Data acquired with the COBE Differential Microwave Radiometer (DMR) provide a unique opportunity to observe simultaneous emission from cosmic gamma-ray bursts in the previously unexplored microwave region of the spectrum. We have searched the COBE DMR time-ordered data sets for instances when one of the DMR horns (FWHM ~ 7°) was pointing in the direction of a gamma-ray burst at the time of burst occurrence. During the overlap period 1991 April-December corresponding to the first public release of COBE data, 210 Compton Gamma Ray Observatory (CGRO)/BATSE gamma-ray bursts listed in the Third BATSE (3B) Catalog were viewable by the COBE DMR. For five of these events the DMR was pointing within 7° of the burst positions at the exact moment of burst occurrence. For another four events the DMR was pointed within 2° of the BATSE positions within 10 s of the burst trigger time. No obvious microwave emission (at 31.5, 53, or 90 GHz), with upper limits in the 10-100 kJy range, can be associated with any of these events. The COBE DMR has a relatively low sensitivity for the detection of point sources within its field of view. A positive detection of a gamma-ray burst by the COBE DMR would imply that the integrated microwave flux must be of the same order as the energy observed in gamma rays. By extending an acceptance window in time of up to 20 minutes before and after a gamma-ray burst another 60 bursts are sampled by the DMR, whose signals are analyzed statistically. We conclude that the "average" gamma-ray burst produces less than about 7-42 kJy in simultaneous microwave radiation.

We are investigating the COBE DMR data at instances of known γ-ray bursts (GRBs) when any of the six DMR horn directions was coincident with the direction of a burst. The BATSE instrument on board GRO has detected 207 bursts during the eight-month period of overlap corresponding to the current release of COBE data. The odds of a GRB occurring within the DMR field of view are near one coincidence per year. Here we report on one such serendipitous observation in 1991, GRB 911226, for which a detailed analysis is currently in progress.

Vaginal lactobacilli assessed by PCR-based microarray and PCR-based genotyping of HPV in South African women at risk for HIV and BV. Vaginal lactobacilli can be defined by microarray techniques in fixed cervical samples of South African women. Cervical brush samples suspended in the coagulant fixative BoonFix of one hundred women attending a health centre for HIV testing in South Africa were available for this study. In the Ndlovu Medical Centre in Elandsdoorn, South Africa, identification of 18 hr-HPV genotypes was done using the INNO-LiPA method. An inventory of lactobacilli organisms was performed using microarray technology. On the basis of the Lactobacillus and Lactobacillus biofilm scoring, the cases were identified as Leiden bacterial vaginosis (BV) negative (BV-; n = 41), Leiden BV intermediate (BV±; n = 25), and Leiden BV positive (BV+; n = 34). Fifty-one women were HIV positive and 49 HIV negative. Out of the 51 HIV positive women, 35 were HPV infected. These 51 HIV positive women were frequently infected with HPV16 and HPV18. In addition, HPV35, HPV52, HPV33, and HPV66 were often detected in these samples. Lactobacillus salivarius and Lactobacillus iners were the most prevalent lactobacilli as established by the microarray technique. In women with HPV infection, the prevalence of Lactobacillus crispatus was significantly reduced. In both HIV and HPV infection, a similar (but not identical) shift in the composition of the lactobacillus flora was observed. We conclude that there is a shift in the composition of vaginal lactobacilli in HIV-infected women. Because of the prominence of HPV35, HPV52, HPV33, and HPV66, vaccination for exclusively HPV16 and HPV18 might be insufficient in South African HIV+ women. Copyright © 2012 Wiley Periodicals, Inc.

Metaplastic cells with nebular cytoplasmic changes in the cervical smear are classified in the Dutch coding system for cervical screening as KOPAC O8 cells. Since these nebulated cells are already documented by Papanicolaou, we refer to these cells as Papanicolaou's nebular cells. We examined the simultaneous presence of these characteristic metaplastic cells and high-grade squamous intraepithelial lesion (HSIL) in a population-based data base from January 1991 and December 1996. The odds ratio (OR) of nebular cells concurring with HSIL increases with age. For the age cohort 30 years, the OR was 7.8 with a 95% confidence interval (CI) of 4.4–13.9. For the age cohort 60 years, the OR was 35.3 with a 95% CI of 7.8–159.2. Aiming to determine the nature of these nebular metaplastic cells, we performed Chlamydia and HPV PCR on 587 and 1,483 smears, respectively. With an OR of 0.9 [0.3–2.4] it is unlikely that Chlamydia plays a role in the appearance of these nebular cells in the smear. This study shows that with an OR of 5.9 [1.7–21.3] HPV is not only related to large koilocytosis but also to a nebular change of small metaplastic cells. This study reports that nebular changes of small metaplastic cells are related to cervical cancer and to HPV infection. Diagn. Cytopathol. 2012. © 2010 Wiley Periodicals, Inc.

The Dutch cytological coding system, KOPAC, enables to code for eight inflammatory events, that is koilocytosis (related to human papillomavirus (HPV)), Trichomonas, dysbacteriosis [related to bacterial vaginosis (BV)], Candida, Gardnerella, Actinomyces, Chlamydia, and non-specific inflammation (leucocytosis). This study presents an analysis of 1,008,879 smears. Of each smear, the age of the woman and the reason for smear taking (screening or indication) was available. The cytoscores (per mille) for these codes were calculated. For the screening smears, the cytoscores were for koilocytosis (HPV) 2.6, for Trichomonas vaginalis 1.9, for dysbacteriosis 31.4, for Candida albicans 9.8, for Gardnerella vaginalis 0.7, for Actinomyces 6.9, for Chlamydia 0.8, and for non-specific inflammatory changes 66.4. For the calculation of the Odds Ratio (OR), normal smears were used as a reference. The cytoscores for Chlamydia and Gardnerella covaried with high grade SIL (HSIL), with an OR of 7 and 12, respectively. In addition, the OR for Trichomonas vaginalis, for dysbacteriosis, and for leucocytosis proved to be significantly high in the indication smears. This study provides an oversight of HSIL and the full range of cervical infections as detected by cytology, proving that this infectious byproduct of screening can be very valuable. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc.

BACKGROUND. Nearly every Dutch woman will be exposed to genital human papillomavirus (HPV) at least once during her lifetime, and most likely several times. In the current study, the authors investigated the prevalence of high-risk–HPV (HR-HPV) infection and the likelihood of progression to cervical intraepithelial neoplasia (CIN). METHODS. In this study, the course of HR-HPV infection in 703 women was observed. From a database of 720,016 negative cytology smears, the authors selected 703 women based on the availability of at least 2 HR-HPV polymerase chain reaction tests. The authors database stores not only the HPV data but also all other cytologic and histologic data, allowing the detection of women who progressed from negative cytology to CIN within a period of 10 years. RESULTS. Of the 703 selected women, 159 were found to have alternating HR-HPV infection (change from a negative HR-HPV test to a positive test or vice versa), 40 had a persistently positive HR-HPV test, and 504 women had a persistently negative HR-HPV test. The percentage of alternating HPV infection declined over time from 37% to 7%. Of the women age older than 40 years, 17% had an alternating HR-HPV infection, 2 of whom developed CIN. These findings led the authors to conclude that all the women in the current study with an increased risk of developing type 2 or 3 CIN were identified using 2 HPV tests. Women age older than 40 years still have a significant risk of acquiring a HR-HPV. CONCLUSIONS. In light of the current study findings, the authors believe it is worth considering the inclusion of women age 40 years and older who have negative cytology for HPV testing as part of the Dutch national screening program. Cancer (Cancer Cytopathol) 2006. © 2006 American Cancer Society.

The scheduling of a school, where students, teachers, rooms and lessons are to be assigned according the curriculum, is a large combinatorial optimization problem. It appears that there are many solutions for a medium‐sized Dutch secondary school, of the order of 102400. We have developed a computational method to find good solutions.

We report on an extension of earlier work to search the archival database of the Differential Microwave Radiometers (DMR) aboard the COBE satellite for evidence of transient events at microwave wavelengths associated with cosmic gamma-ray bursts (GRBs). Over its four-year lifetime the DMR experiment repeatedly surveyed the sky to measure fluctuations in the cosmic microwave background. On a number of occasions at least one of the horns of the DMR was also serendipitously pointing in the direction of a cosmic gamma-ray burst at the moment of burst occurrence. Our original investigation covered the eight-month period April–December 1991 when a number of GRBs were observed by the COBE/DMR at or within a few seconds of the CGRO/BATSE trigger time. Upper limits only were obtained for any simultaneous microwave flux from these events, in the range 7–42 kJy. Most recently, we have extended our search using the additional 24 months of COBE DMR data now publicly available, covering the time period January 1992 thr...

We report on the status of our ongoing project to search the database of the COBE Differential Microwave Radiometer (DMR) experiment for transient signals at microwave wavelengths simultaneous with cosmic gamma-ray bursts (GRBs). To date we have carried out a complete search of the DMR database using burst positions taken from the original BATSE 1B catalog for the eight-month period of overlap (May–December 1991) corresponding to the first public release of COBE data. We are currently repeating our original search of the COBE DMR database using the revised burst positions of the newly-released BATSE 3B catalog. Using BATSE 1B positions, at least two apparent simultaneous observations of GRBs by the COBE DMR occurred in 1991, along with a number of “near misses” within 30 seconds in time. At present, only upper limits to burst microwave emission are indicated. Even in the event of a non-detection of a GRB by the COBE DMR, unprecedented observational limits will still be obtained, constraining the predictio...

This paper describes an unusual mode of application of MemSys5, viz. its usefulness in finding inconsistencies in data or noise estimates. Some recommendations for users of MemSys5 is given at the end.

From the all-sky infra-red survey of the IRAS satellite, a dataset was prepared for an image reconstruction contest. The object for reconstruction was an image of the galaxy M51. The entries were judged by a panel of astronomers. The judging criterion was which entry brings out the most astronomy.

Some years ago, Willems & de Jong (1988) noticed that many carbon stars display an excess of emission at 60 µm and explained it by the presence of a fossil dust shell, containing only cold dust. This detached dust shell would be the result of an interruption of the mass loss, consequence of a thermal pulse. Detached shells around C stars have actually been mapped in the CO lines (Olofsson et al. 1992), and at 60µm (Waters et al. 1994). In 1992, Zijlstra et al. found about 100 M stars displaying an excess of emission at 60 µm, and proposed that interruptions of the mass loss due to thermal pulses is a general phenomenon on the AGB. This assumption is now supported by the theoretical calculations of Vassiliadis & Wood (1993). Here we present a detailed study of the 100 M stars of Zijlstra et al. in order to test the previous assumption.

The InfraRed Astronomical Satellite (IRAS) all-sky survey was designed and optimized for the detection of point sources. This allowed the survey to be conducted in the form of narrow strip scans with redundant coverage of the sky, but with non-uniform covering densities. The data shows in addition to point sources many sources of extended emission, which are best analyzed from images. However, the non-uniform coverage now forms a significant obstacle in the image (re-)construction. Low resolution images, such as in the Infrared Sky Survey Atlas, yield spatial resolutions of 5–10 times the IRAS telescope diffraction limit; HIRAS improves this to 1–2 times!