Are Maori under-served for cardiac interventions?

AIMS

To examine hospitalisation rates for selected heart-disease-related diagnoses by age, gender, ethnicity and deprivation.

METHODS

Four years' data on publicly-funded hospital discharges for: (i) heart failure and (ii) cardiac interventions were cross-classified by age group, gender, ethnicity (Maori/non-Maori) and deprivation (NZDep96). Population hospitalisation rates were calculated and displayed in multi-dimensional trellis graphs.

RESULTS

The graphs show patterns of hospitalisation for chosen variables simultaneously. The expected increase in heart failure with age is found, as is an increase for the cardiac group up to ages 65-74 years. Clear gender differences were found. A further increase of heart failure with higher deprivation is evident throughout. For cardiac interventions, the relationship with deprivation is complex. Differences by ethnicity are disturbing. Hospitalisation rates for heart failure for Maori are typically more than double the non-Maori rates. In contrast, for the cardiac group Maori intervention rates are much lower.

CONCLUSIONS

Graphical analysis that displays age, gender, ethnicity and deprivation simultaneously provides great insight into hospitalisation rates. Ethnic differences are particularly concerning and raise important questions about how well Maori needs are being met and how equitable is access to cardiac interventions for Maori.

HIV infection in families of HIV-positive and 'at-risk' HIV-negative women

Research of HIV infection within the family has focused upon sexual partners and vertical transmission. The scope of the problem of multiple infections and clustering of HIV among family members has, thus far, been less extensively explored. The objectives of this study are to investigate HIV infection in family members of HIV-seropositive and HIV-seronegative high-risk women and to consider the impact of multiple HIV infections within the family. Baseline data were evaluated from a prospective observational cohort of 871 HIV-seropositive and 439 seronegative at-risk women who are participants in a longitudinal study of HIV in women at four sites in the USA (Montefiore, Bronx, NY; Johns Hopkins University, Baltimore, MD; Brown University, Providence, RI; Wayne State University, Detroit, MI). Women were asked if anyone close to them had HIV/AIDS or had died from HIV/AIDS. Responses which included HIV-positive family members were analyzed. In the seropositive cohort, 35% (307/871) of the women had a family member with HIV infection. Of these 307 women, 38% reported having a sibling, 24% a husband and 27% had more than one family member with HIV/AIDS. Forty-nine per cent of Latina women, 34% of black women, and 21% of white women reported having a family member with HIV/AIDS. Using logistic regression analysis, we found that Latina and black women were significantly more likely than white women to have a sibling, extended family member or more than one family member with HIV/AIDS. Compared to seropositive women, seronegative high-risk women enrolled in this study appear equally likely to have an HIV-infected family member. In this study of HIV-positive women and high-risk seronegative women, a third reported having multiple family members with HIV infection, most often in a sibling. The high prevalence of HIV within families, particularly in the families of Latina and black women, mandates attention in planning both prevention and care.

Characterization of the Hox cluster from the mosquito Anopheles gambiae (Diptera: Culicidae)

The Hox genes have been found to encode transcription factors, which specify the morphological identity of structures along the anteroposterior axis of animals ranging from worms to mice. The canonical set of nine genes is organized in a cluster in the genome of several protostomes and deuterostomes. However, within insects, whereas the Hox genes are organized in a single cluster in the beetle Tribolium castaneum, they are split into two separate groups in the flies Drosophila melanogaster and Drosophila virilis. The significance of a split Hox cluster is unknown and has been observed in only one organism outside the Drosophila lineage: the nematode Caenorhabditis elegans. We have cloned a majority of the Hox genes from the mosquito Anopheles gambiae (Diptera: Culicidae) and compared their genomic organization with that of Tribolium and Drosophila to determine if a split Hox cluster is found in dipterans aside from the Drosophilidae. We find that the Hox genes in Anopheles, as in Tribolium, are organized in a single cluster that spans a genomic region of at least 700 kb. This finding suggests that, within the insect genome, the partition of the Hox cluster may have evolved exclusively within the Drosophila lineage. The genomic structures of the resident genes, however, appear to be largely conserved between A. gambiae and D. melanogaster.

Glucocorticoid-associated maternal hyperglycemia: a randomized trial of insulin prophylaxis

OBJECTIVES

To study the degree and timing of maternal hyperglycemia following betamethasone therapy in nondiabetic patients and establish a prophylactic dose of insulin.

METHODS

Forty-five patients receiving betamethasone 12 mg i.m. at 7 AM on two consecutive days were randomized to no insulin (n = 20), low-dose insulin (n = 18), and high-dose insulin (n = 7) protocols. Each treatment group received s.c. insulin at 7 AM on the 2 days of betamethasone therapy (20 units NPH/10 units regular, and 40 units NPH/20 units regular, respectively). Capillary plasma glucose measurements were obtained at fasting and 2 h after meals for 3 days. A multivariate normal regression model was used to estimate and compare mean glucose levels.

RESULTS

Eighty-five percent of patients who did not receive insulin exhibited hyperglycemia at levels previously associated with fetal acidosis. Significant differences in mean postprandial plasma glucose levels were found between the no-treatment and insulin groups on days 1 and 2. No significant differences were noted between groups on day 3.

CONCLUSIONS

Transient maternal hyperglycemia occurs in a consistent pattern in nondiabetic patients receiving betamethasone, which can be limited by the concurrent use of insulin. Further studies to assess fetal acidosis in this setting are warranted.

Pregnancy and pregnancy outcome in hepatitis C type 1b

A large cohort of rhesus-negative women in Ireland were inadvertently infected with hepatitis C virus following exposure to contaminated anti-D immunoglobulin in 1977-8. This major iatrogenic episode was discovered in 1994. We studied 36 women who had been infected after their first pregnancy, and compared them to an age- and parity-matched control group of rhesus-positive women. The presence of hepatitis C antibody was confirmed in all 36 by enzyme-linked immunosorbent assay and by recombinant immunoblot assay, while 26 (72%) of the cohort were HCV-RNA-positive (type 1b) on PCR testing. In the 20 years post-infection, all members of the study group had at least one pregnancy, and mean parity was 3.5. They had a total of 100 pregnancies and 85 of these went to term. There were four premature births, one being a twin pregnancy, and 11 spontaneous miscarriages. One miscarriage occurred in the pregnancy following HCV infection. There were two neonatal deaths due to severe congenital abnormalities in the PCR-positive women. Of the children born to HCV-RNA positive mothers, only one (2.3%) tested positive for the virus. Significant portal fibrosis on liver biopsy was confined to HCV-RNA-positive mothers apart from one single exception in the antibody-positive HCV-RNA-negative group. Comparison with the control group showed no increase in spontaneous miscarriage rate, and no significant difference in obstetric complications; birth weights were similar for the two groups.

Outcome of very low birth weight infants with histopathologic chorioamnionitis

OBJECTIVE

To determine neonatal outcome at 7 months of corrected age in very low birth weight (VLBW) infants with placental chorioamnionitis.

METHODS

We conducted a cohort study of 287 VLBW infants delivered as a result of preterm premature rupture of membranes (PROM) or preterm labor. Control subjects (n = 123) had placentas with absent umbilical cord inflammation and absent or low-grade membrane inflammation. Case subjects (n = 164) had moderate membrane inflammation or any umbilical cord inflammation. Neonatal and 7-month outcomes were compared. A power analysis showed that 98 total subjects were needed to reject the two-sided null hypothesis with a difference in mean Bayley index scores of at least 8.

RESULTS

Infants in the study group had significantly more preterm PROM, antenatal antibiotics, lower birth weight, lower gestational age, longer duration of ruptured membranes, and clinical chorioamnionitis. Intraventricular hemorrhage occurred more commonly in infants with placentas demonstrating chorioamnionitis (relative risk = 1.6, 95% confidence interval 1.1, 2.4, P =.013). One hundred sixty-seven (69%) of the 243 surviving infants had 7-month follow-up. There was no difference between cases and controls in mean Bayley mental developmental index (93 compared with 90, P =.25), psychomotor developmental index (89 compared with 90, P =.68), or in the number of infants that were developmentally delayed.

CONCLUSION

Despite a higher frequency of intraventricular hemorrhage, no difference in developmental scores was detected at 7 months of corrected age in VLBW infants with histologic chorioamnionitis.

Staff ratios in intensive care: are they adequate?

The Department of Health (DoH) (2000) review of adult critical care services recommends a move away from the rigid 1:1 nurse/patient staffing ratio that operates within intensive care units (ICUs) to a more flexible system based on the assessment of nursing workload.

The utilization of the healthcare assistant role in intensive care

The increasing role of healthcare assistants (HCAs) in intensive care in relation to patient monitoring has raised concerns among some clinical managers, particularly where such roles are not underpinned by a sound knowledge base and critical reasoning ability. This article describes a study which was undertaken in an attempt to identify how HCAs are currently utilized within the general intensive care environment. The results show a wide variation between units in relation to the activities undertaken by HCAs, their training and the levels of remuneration. This article seeks to open up the debate as to whether or not nurses should be challenging the nursing care that is now delivered by non-nurses and makes recommendations for the way forward in this area.

Linkage of familial schizophrenia to chromosome 13q32

Over the past 4 years, a number of investigators have reported findings suggestive of linkage to schizophrenia, with markers on chromosomes 13q32 and 8p21, with one recent study by Blouin et al. reporting significant linkage to these regions. As part of an ongoing genome scan, we evaluated microsatellite markers spanning chromosomes 8 and 13, for linkage to schizophrenia, in 21 extended Canadian families. Families were analyzed under autosomal dominant and recessive models, with broad and narrow definitions of schizophrenia. All models produced positive LOD scores with markers on 13q, with higher scores under the recessive models. The maximum three-point LOD scores were obtained under the recessive-broad model: 3.92 at recombination fraction (theta).1 with D13S793, under homogeneity, and 4.42 with alpha=.65 and straight theta=0 with D13S793, under heterogeneity. Positive LOD scores were also obtained, under all models, for markers on 8p. Although a maximum two-point LOD score of 3.49 was obtained under the dominant-narrow model with D8S136 at straight theta=0.1, multipoint analysis with closely flanking markers reduced the maximum LOD score in this region to 2. 13. These results provide independent significant evidence of linkage of a schizophrenia-susceptibility locus to markers on 13q32 and support the presence of a second susceptibility locus on 8p21.

Genetics in the study of mosquito susceptibility to Plasmodium

Within the past several years, a number of powerful genetic and genomic tools have been developed for use in research on the African malaria vector Anopheles gambiae. While these tools have been developed with a broad range of potential applications in mind, they have been particularly useful in advancing the effort to clone a set of An. gambiae genes that enable a refractory strain of this mosquito to encapsulate and kill a wide variety of different malaria parasites to which this mosquito is normally fully susceptible. This paper describes the latest progress in this map-based cloning research, which involves the collaborative contributions of a number of different laboratories in Europe and the United States.

A comparison of bronchodilator therapy delivered by nebulization and metered-dose inhaler in mechanically ventilated patients

BACKGROUND

The optimal method of delivering bronchodilators in mechanically ventilated patients is unclear. The purpose of this study was to compare the pulmonary bioavailability of albuterol delivered by the nebulizer, the metered-dose inhaler (MDI) and spacer, and the right-angle MDI adaptor in ventilated patients using urinary analysis of drug levels.

METHODS

Mechanically ventilated patients who had not received a bronchodilator in the previous 48 h and who had normal renal function were randomized to receive the following: (1) five puffs (450 microg) of albuterol delivered by the MDI with a small volume spacer; (2) five puffs of albuterol delivered by the MDI port on a right-angle adaptor; or (3) 2.5 mg albuterol delivered by a nebulizer. Urine was collected 6 h after the administration of the drug, and the amounts of albuterol and its sulfate conjugate were determined in the urine by a chromatographic assay.

RESULTS

Thirty patients were studied, 10 in each group: their mean age and serum creatinine level were 62 years and 1.3 mg/dL, respectively. With the MDI and spacer, (mean +/- SD) 169+/-129 microg albuterol (38%) was recovered in the urine; with the nebulizer, 409+/-515 microg albuterol (16%) was recovered in the urine; and with the MDI port on the right-angle adaptor, 41+/-61 microg albuterol (9%) was recovered in the urine (p = 0.02 between groups). The level of albuterol in the urine was below the level of detection in four patients in whom the drug was delivered using the right-angle MDI adaptor.

CONCLUSION

The three delivery systems varied markedly in their efficiency of drug delivery to the lung. As previous studies have confirmed, this study has demonstrated that using an MDI and spacer is an efficient method for delivering inhaled bronchodilators to the lung. The pulmonary bioavailability was poor with the right-angle MDI port. This port should not be used to deliver bronchodilators in mechanically ventilated patients.

Comparison of maternal serum total activin A and inhibin A in normal, preeclamptic, and nonproteinuric gestationally hypertensive pregnancies

OBJECTIVE

The aim of the study was to compare maternal serum levels of activin A and inhibin A in pregnancy complicated by preeclampsia, pregnancy complicated by gestational hypertension, and normal pregnancy from 25 to 42 weeks' gestation.

STUDY DESIGN

Activin A and inhibin A levels were measured by 2-site enzyme-linked immunosorbent assay in 60 subjects with preeclampsia, 60 control normotensive pregnant women matched for gestational age, and 51 unmatched subjects with gestational hypertension.

RESULTS

Activin A levels were higher in the preeclampsia group (median 31.5 ng/mL and interquartile range 10.5 ng/mL) than in the control group (median 10.6 ng/mL and interquartile range 9.5 ng/mL, P <.0001) and the gestational hypertension group (median 21.4 ng/mL and interquartile range 15.2 ng/mL, P <.003). Inhibin A levels were greater in the preeclampsia group (median 1833 pg/mL and interquartile range 1464 pg/mL) than in control subjects (median 698 pg/mL and interquartile range 583 pg/mL, P <.0001). Control levels were significantly related to gestational age.

CONCLUSIONS

Levels of both analytes were greater in preeclampsia and activin A levels were greater in gestational hypertension than in normotensive pregnancy. These analytes may prove to be clinically useful laboratory markers for preeclampsia.

Distribution of uranium in rats implanted with depleted uranium pellets

During the Persian Gulf War, soldiers were injured with depleted uranium (DU) fragments. To assess the potential health risks associated with chronic exposure to DU, Sprague Dawley rats were surgically implanted with DU pellets at 3 dose levels (low, medium and high). Biologically inert tantalum (Ta) pellets were used as controls. At 1 day and 6, 12, and 18 months after implantation, the rats were euthanized and tissue samples collected. Using kinetic phosphorimetry, uranium levels were measured. As early as 1 day after pellet implantation and at all subsequent sample times, the greatest concentrations of uranium were in the kidney and tibia. At all time points, uranium concentrations in kidney and bone (tibia and skull) were significantly greater in the high-dose rats than in the Ta-control group. By 18 months post-implantation, the uranium concentration in kidney and bone of low-dose animals was significantly different from that in the Ta controls. Significant concentrations of uranium were excreted in the urine throughout the 18 months of the study (224 +/- 32 ng U/ml urine in low-dose rats and 1010 +/- 87 ng U/ml urine in high-dose rats at 12 months). Many other tissues (muscle, spleen, liver, heart, lung, brain, lymph nodes, and testicles) contained significant concentrations of uranium in the implanted animals. From these results, we conclude that kidney and bone are the primary reservoirs for uranium redistributed from intramuscularly embedded fragments. The accumulations in brain, lymph nodes, and testicles suggest the potential for unanticipated physiological consequences of exposure to uranium through this route.

Analysis of uroliths from cats and dogs in New Zealand, 1993-96

AIMS

Canine and feline uroliths were analysed to determine the prevalence of particular types of urolith and the dog breeds at risk.

METHODS

Three hundred and sixty-nine uroliths recovered from 316 dogs and 53 cats between November 1993 and December 1996 were analysed by X-ray diffraction, and by infrared spectrometry where X-ray diffraction alone was non-diagnostic.

RESULTS

Bitches of small breeds especially Welsh corgi and Bichon frise, were most frequently affected. Struvite was the most common urolith (204 dogs). Oxalate (60 dogs) was the second most prevalent urolith identified, followed by cystine (24 dogs). The breeds producing cystine calculi were: Dalmatian, Bassett hound, Borzoi, Newfoundland, Shetland sheepdog, Labrador, Chihuahua, Fox terrier, English bulldog, Bichon frise, Doberman pinscher, Border collie. Silica uroliths were identified for the first time in New Zealand. All feline uroliths were struvite.

CONCLUSION

The results are useful in determining the prevalence of specific types of urolith in New Zealand and the breeds at risk of forming them.

Urinary and serum mutagenicity studies with rats implanted with depleted uranium or tantalum pellets

During the 1991 Persian Gulf War several US military personnel were wounded by shrapnel fragments consisting of depleted uranium. These fragments were treated as conventional shrapnel and were not surgically removed to spare excessive tissue damage. Uranium bioassays conducted over a year after the initial uranium injury indicated a significant increase in urine uranium levels above natural background levels. The potential mutagenic effects of depleted uranium are unknown. To assess the potential mutagenic effects of long-term exposure to internalized depleted uranium, Sprague-Dawley rats were implanted with depleted uranium and their urine and serum were evaluated for mutagenic potential at various times after pellet implantation using the Ames Salmonella reversion assay. Tantalum, an inert metal widely used in prosthetic devices was used for comparison. Enhancement of mutagenic activity in Salmonella typhimurium strain TA98 and the Ames II mixed strains (TA7001-7006) was observed in urine samples from animals implanted with depleted uranium pellets. In contrast, urine samples from animals implanted with tantalum did not show a significant enhancement of mutagenic activity in these strains. In depleted uranium-implanted animals, urine mutagenicity increased in a dose- and time-dependent manner demonstrating a strong positive correlation with urine uranium levels (r = 0.995, P < 0.001). There was no mutagenic enhancement of any bacterial strain detected in the sera of animals implanted with either depleted uranium or tantalum pellets. The results suggest that uranium content in the urine is correlated with urine mutagenicity and that urinary mutagenicity might be used as a biomarker to detect exposure to internalized uranium.

Human papillomavirus and mixed epithelial tumors of the endometrium

Strong epidemiological evidence links human papilloma viruses (HPV) with the development of cervical intraepithelial neoplasia (CIN) and invasive cancers of the uterine cervix. The localization of HPV DNA sequences high up in the female genital tract (in benign and malignant lesions) is not that uncommon, but its precise significance is uncertain. In particular, the detection of HPV DNA sequences by polymerase chain reaction (PCR) needs careful interpretation, because the source of the amplicon may emanate from tumor cells, direct contamination from the cervix, or possibly from extratumoral sites in the endometrium. We have previously reported the identification of koilocyte-like changes in the squamous epithelium of some endometrial adenoacanthomas. Adenoacanthomas (adenocarcinoma with squamous metaplasia) are mixed epithelial tumors arising in the endometrium composed of malignant glandular areas admixed with benign metaplastic squamous epithelium. The rarer adenosquamous carcinoma containing both malignant glandular and squamous areas is also described. The origin of benign/malignant squamous epithelial islands in endometrial tumors has been the subject of speculation, with some investigators considering an origin from metaplastic glandular endometrial cells. In this study, we examined 10 normal endometrial samples, 20 adenocarcinomas, 41 adenocarcinomas with squamous metaplasia, and two adenosquamous carcinomas, (including control cervical material where possible) for the presence of HPV DNA sequences using nonisotopic in situ hybridization (NISH), type-specific HPV PCR, general primer PCR (to detect sequenced and unsequenced HPVs), and PCR in situ hybridization (PCR-ISH). We did not identify HPV DNA sequences in normal endometrial tissue. In adenocarcinomas (endometrioid type), HPV was only identified in 2 of 20 cases by PCR, both of which were HPV 11 positive. We were unsuccessful in identifying HPV in endometrial carcinomas by NISH or by PCR-ISH, raising the possibility of contamination from the cervix in the two positive cases. In adenoacanthomas, a low-risk HPV type (HPV 6) was found in 19 of 41 cases. NISH signals were intranuclear in location in squamous regions of adenoacanthomas. Additional positive nuclei were uncovered using PCR-ISH, which increases the sensitivity of standard NISH detection. HPV DNA sequences were located in some malignant endometrial glandular epithelial cells, but this accounted for a minority of samples. HPV DNA sequences were not detected in extraepithelial sites. Mixed infection by two different HPV types was identified in two cases. Most cases showed similar HPV types in cervical and endometrial lesions, although discordant cases were uncovered. In adenosquamous carcinomas, one case showed mixed infection with HPV 6 and 33 by PCR. The apparent segregation of low-risk HPV type (HPV 6) with benign squamous metaplastic epithelium in adenocarcinoma with squamous metaplasia, and high-risk type (HPV 33) with malignant squamous epithelium in adenosquamous carcinoma, raises important questions in relation to the role of HPVs in mixed epithelial tumors of the endometrium and their interplay in the pathogenesis of squamous metaplasia at extracervical sites.

Use of a quantitative trait to map a locus associated with severity of positive symptoms in familial schizophrenia to chromosome 6p

A number of recent linkage studies have suggested the presence of a schizophrenia susceptibility locus on chromosome 6p. We evaluated 28 genetic markers, spanning chromosome 6, for linkage to schizophrenia in 10 moderately large Canadian families of Celtic ancestry. Parametric analyses of these families under autosomal dominant and recessive models, using broad and narrow definitions of schizophrenia, produced no significant evidence for linkage. A sib-pair analysis using categorical disease definitions also failed to produce significant evidence for linkage. We then conducted a separate sibpair analysis using scores on positive-symptom (psychotic), negative-symptom (deficit), and general psychopathology-symptom scales as quantitative traits. With the positive symptom-scale scores, the marker D6S1960 produced P = 1.2 x 10(-5) under two-point and P = 5.4 x 10(-6) under multipoint analyses. Using simulation studies, we determined that these nominal P values correspond to empirical P values of .034 and .0085, respectively. These results suggest that a schizophrenia susceptibility locus on chromosome 6p may be related to the severity of psychotic symptoms. Assessment of behavioral quantitative traits may provide increased power over categorical phenotype assignment for detection of linkage in complex psychiatric disorders.

Alterations in exon 1 of c-myc and expression of p62c-myc in cervical squamous cell carcinoma

AIMS

To examine human papillomavirus (HPV) positive and negative squamous cell carcinomas of the cervix for structural alterations in exon 1 c-myc; and to investigate the expression pattern of p62, the protein product of c-myc.

MATERIAL

Archival paraffin wax embedded tissues of cervical squamous cell carcinomas, stage I and II, retrieved from the files of the department of pathology, University College Cork, Ireland: 40 cases were examined for alterations in exon 1 of c-myc; 57 cases were used for immunocytochemical p62 analysis.

METHODS

c-myc exon 1 PCR on HPV positive and negative stage I and II cervical squamous cell carcinomas was performed using primers designed to fragile sites in exon 1 of the c-myc oncogene, which are frequently involved in translocation phenomena and deletions in other neoplasms. This region is bordered by two promoter sequences P1 and P2. In addition, the expression of p62 was evaluated using the monoclonal antibody Mycl-9E10.

RESULTS

Alterations in exon 1 of c-myc were shown in 7.5% of squamous cell carcinomas of the cervix. Changes in exon 1 and 2 of c-myc were also found in COLO 320 cells and Raji cells. These alterations were due to small deletions within exon 1 of c-myc, but point polymorphisms occurring within the priming sites (in one case) may also have occurred. The alterations uncovered appeared "clonal," as replicate samples showed the same amplicon band pattern. Expression of c-myc was variable, with cytoplasmic staining patterns predominating. All cases which showed exon 1 alterations were HPV positive and had strong nuclear positivity on p62 immunocytochemistry.

CONCLUSIONS

Alterations in exon 1 of c-myc occur in a minority of cervical cancers and there was increased expression of p62 in a cohort of HPV positive and negative cervical squamous cell carcinomas. Exon 1 alterations may provide an alternative route to c-myc activation in early squamous cell carcinoma.

Genotypic mapping of HPV and assessment of EBV prevalence in endocervical lesions

AIMS

To examine the prevalence of human papillomavirus (HPV) and Epstein-Barr virus (EBV) in low grade glandular intraepithelial lesions of the cervix, adenocarcinoma with high grade glandular intraepithelial lesions combined, and adenocarcinomas; and to perform a genotyping mapping analysis of endocervical carcinomas to determine the extent of HPV infections in such lesions.

MATERIAL

Archival paraffin wax embeded material from the files of the departments of pathology, National Maternity Hospital, Dublin, and University College Cork, Ireland.

METHODS

HPV prevalence was examined using type specific HPV PCR, general primer HPV PCR (pan HPV screen), nonisotopic in situ hybridisation (NISH), and PCR in situ hybridisation (PCR-ISH). In situ hybridisation was performed using fluorescein labelled oligonucleotide cocktail for eber transcripts of EBV. Genotypic analysis was performed, in all cases where possible, using a grid system.

RESULTS

HPV 16 and 18 were predominantly identified in low grade glandular intraepithelial lesions, high grade glandular intraepithelial lesions, and adenocarcinomas, with HPV prevalence increasing with grade of dysplasia. EBV was only identified in subepithelial lymphocytes in a minority of cases. No link could be shown between HPV and EBV in endocervical lesions. HPV infection was not clonal in endocervical cancer and coexistent adjacent cervical intraepithelial neoplasia, where present, tended to show a similar HPV type.

CONCLUSIONS

The restriction of HPV types 16 and 18 to endocervical lesions suggests that their effect is restricted and specific to endocervical mucosa, but the mechanism of interaction is currently unknown.

Flow cytometric analysis of platelet activation throughout normal gestation

OBJECTIVE

To measure platelet activation in normal pregnancy, before and after stimulation with agonists, with a whole blood flow cytometric technique.

METHODS

In a cross-sectional study, 5 mL of whole blood was collected from healthy volunteers (nine in the first trimester, ten in the second trimester, 35 in the third trimester, and 32 nonpregnant controls). Platelets were treated with an agonist (thrombin or U-46619, a thromboxane A2 analogue) or buffer and were exposed to saturating concentrations of monoclonal antibodies directed against platelet membrane glycoproteins (GPs): 7E3 (fibrinogen receptor GPIIb/IIIa), S12 (alpha granule marker P-selectin), and 6D1 (von Willebrand factor receptor GPIb). Mean fluorescence intensity was determined for 5000 platelets per sample by using a flow cytometer.

RESULTS

In the absence of agonist, no significant difference between groups was found in antibody binding. At no stage of pregnancy were circulating activated platelets detected. Platelets from third-trimester subjects bound significantly less 7E3 than platelets of controls or of first- or second-trimester subjects after stimulation with high-dose thrombin (P < .05 for all comparisons). Down-regulation of 6D1 on platelets after stimulation with high-dose U-46619 was significantly greater in third-trimester gravidas than in controls or first-trimester subjects (P < .05).

CONCLUSION

Pregnancy does not increase the percentage of activated platelets in the circulation. Platelet reactivity is altered in the third trimester, as evidenced by decreased antibody binding to fibrinogen receptor epitope and enhanced down-regulation of a von Willebrand factor receptor epitope.