Reductions of vascular endothelial growth factor and placental growth factor concentrations in severe preeclampsia

OBJECTIVE

The aim of this study was to determine whether plasma concentrations of vascular endothelial growth factor and placental growth factor are altered in women with severe preeclampsia.

STUDY DESIGN

We performed a case-control study to compare plasma concentrations of vascular endothelial growth factor and placental growth factor between women with severe preeclampsia and normotensive women admitted for delivery. Twenty-one women with severe preeclampsia were matched for gestational age and ethnicity with 21 normotensive women. Vascular endothelial growth factor and placental growth factor concentrations were measured with a specific antigen-capture enzyme-linked immunosorbent assay.

RESULTS

Women with severe preeclampsia demonstrated significantly lower plasma concentrations of both vascular endothelial growth factor (6.36 +/- 3.96 pg/mL vs 18.65 +/- 5.98 pg/mL; P <.0001) and placental growth factor (138 +/- 119 pg/mL vs 531 +/- 340 pg/mL; P <.0001) than did women with normotensive pregnancy. Logistic regression analysis showed an independent association between plasma vascular endothelial growth factor concentration and plasma placental growth factor concentration and preeclampsia.

CONCLUSION

Patients with severe preeclampsia had decreased maternal serum concentrations of both vascular endothelial growth factor and placental growth factor.

Mediastinal staging of non-small-cell lung cancer with positron emission tomography

To determine the usefulness of positron emission tomography with fluoro-2-deoxyglucose (PET-FDG) in assessing mediastinal disease in patients with non-small-cell lung cancer (NSCLC) and to compare its yield to that of computed tomography (CT), we performed a prospective consecutive sample investigation in a university hospital and its related clinics. In 30 patients with NSCLC with clinical stage I (T1-2, NO, MO) disease, we compared the results of chest CT and PET-FDG with the findings at surgical exploration of the mediastinum. Seven (77%) of nine patients with surgically proven mediastinal metastasis were identified by the PET-FDG results, with four false-positives in 21 patients with negative lymph node dissections (p = 0.004). Using the results of pathologic examination of mediastinal lymph nodes as the criterion standard, the diagnostic sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) for PET-FDG imaging of mediastinal metastases were 78%, 81%, 80%, 64%, and 89%, respectively. The sensitivity, specificity, accuracy, PPV, and NPV for chest CT in the detection of mediastinal metastasis were 56%, 86%, 77%, 63%, and 87%, respectively. CT and PET-FDG results agreed in 21 patients. The diagnostic accuracy of the combined imaging modalities was 90%. We concluded that mediastinal uptake of FDG correlates with the extent of mediastinal involvement of NSCLC and may contribute to preoperative staging. PET-FDG imaging complements chest CT in the noninvasive evaluation of NSCLC, and strategies for its use merit further investigation.

In vitro susceptibilities of wild-type or drug-resistant hepatitis B virus to (-)-beta-D-2,6-diaminopurine dioxolane and 2'-fluoro-5-methyl-beta-L-arabinofuranosyluracil

Prolonged treatment of chronic hepatitis B virus (HBV) infection with lamivudine ([-]-beta-L-2',3'-dideoxy-3' thiacytidine) or famciclovir may select for viral mutants that are drug resistant due to point mutations in the polymerase gene. Determining whether such HBV mutants are sensitive to new antiviral agents is therefore important. We used a transient transfection system to compare the sensitivities of wild-type HBV and four lamivudine- and/or famciclovir-resistant HBV mutants to adefovir [9-(2-phosphonyl-methoxyethyl)-adenine; PMEA] and the nucleoside analogues (-)-beta-D-2, 6-diaminopurine dioxolane (DAPD) and 2'-fluoro-5-methyl-beta-L-arabinofuranosyluracil (L-FMAU). The drug-resistant mutants contained amino acid substitutions in the polymerase protein. We found that the M550I and M550V plus L526M substitutions, which confer lamivudine resistance, did not confer cross-resistance to adefovir or DAPD, but conferred cross-resistance to L-FMAU. The M550V substitution in isolation conferred a similar phenotype to M550I, except that it did not confer significant resistance to L-FMAU. The L526M substitution, which is associated with famciclovir resistance, conferred cross-resistance to L-FMAU but not to adefovir or DAPD. Inhibition of HBV secretion by DAPD, L-FMAU, and adefovir did not always correlate with inhibition of the generation of intracellular HBV replicative intermediates, suggesting that these analogs may preferentially inhibit specific stages of the viral replication cycle.

Managing life-threatening hemoptysis: has anything really changed?

STUDY OBJECTIVES

To delineate current chest clinicians' approaches to the management of patients with life-threatening hemoptysis.

DESIGN

Survey during a computer-assisted interactive continuing medical education presentation.

SETTING

The 1998 American College of Chest Physicians (ACCP) Annual Scientific Assembly.

PARTICIPANTS

Chest clinicians attending the respiratory emergency symposium.

RESULTS

Most clinicians (86%) had cared for patients with life-threatening hemoptysis, and 28% had cared for patients with fatal events during the previous year. Those clinicians favored management in the ICU setting (95%) with early endotracheal intubation (85%), and they tended to use a large-bore, single-lumen endotracheal tube (57%). The majority (64%) favored the early performance of diagnostic bronchoscopy during the first 24 h. Most clinicians (79%) used the flexible instrument, a higher frequency than respondents at a similar symposium on hemoptysis at the 1988 ACCP meeting (48%; p < 0.0001). Most current clinicians (77%) had experience with endobronchial measures to control bleeding, but few (14%) found them to be consistently worthwhile. Chest CT scanning was often helpful in diagnosis (55%). In their management of bleeding, half of these clinicians favored the use of interventional angiography, even in operable patients, which is a substantial change from 1988 when 23% had favored this approach (p < 0.0001).

CONCLUSIONS

During the past decade, life-threatening hemoptysis has remained an important problem. Flexible bronchoscopy and interventional angiography have become increasingly established, more widely accepted approaches to patient care.

Interaction of immunoactive monokines (interleukin 1 and tumor necrosis factor) in the bivalve mollusc Mytilus edulis

Mytilus edulis has been the subject of recent studies to determine whether the relationship between the immune and neuroendocrine systems seen in vertebrates also exists in invertebrates. The effects of mammalian monokines were studied in Mytilus immunocytes previously shown to produce and react to opioid peptides. These invertebrate cells respond to interleukin 1 (IL-1) and tumor necrosis factor (TNF), both in vitro and in vivo, in a manner similar to that of human granulocytes. As in the mammalian monokine network, the effect of IL-1 on the immunocytes is brought about, at least in part, by its stimulatory effect on the formation of TNF. In addition, the presence of immunoreactive IL-1 and TNF in Mytilus hemolymph was demonstrated.

Education and experience improve transbronchial needle aspiration performance

To determine whether the diagnostic yield of transbronchial needle aspiration (TBNA) improves over time and to obtain insights about factors influencing its performance, we reviewed our experience during a 3-yr period. After serial multifaceted educational interventions directed toward bronchoscopists and their technical staff, TBNA yield increased significantly from 21.4 to 47.6% (p < 0.001). More frequent and more detailed notations in bronchoscopy reports (p < 0.05), a lower frequency of cytopathology specimens contaminated by endobronchial material (p < 0.05), and higher yields in patients with small cell carcinoma (p < 0.01) suggested that bronchoscopists' TBNA proficiency had increased. More frequent diagnoses with small cell carcinoma and fewer cytologically unsatisfactory specimens (p < 0.01) suggested that education of bronchoscopy technicians, and use of a direct smear technique for specimen preparation also contributed to improved TBNA yield. Increased experience with TBNA and focused education regarding its performance can enhance the role of this procedure in diagnosis and staging of patients with lung cancer.

Staging by positron emission tomography predicts survival in patients with non-small cell lung cancer

BACKGROUND

Positron emission tomography (PET) scanning is used increasingly to detect and stage lung cancer, but the test performance characteristics and relationship of PET to patient outcomes remain undefined.

OBJECTIVE

To determine the test performance characteristics and relationship of PET scanning stage to patient outcomes relative to the 1997 International System for the Staging of Lung Cancer.

DESIGN

Survival analysis using pathologic staging as the criterion standard for comparison of survival as predicted by staging by PET and CT.

SETTING

University-based hospital.

PATIENTS

All consecutive patients undergoing PET scanning for the evaluation of possible non-small cell lung cancer (NSCLC) during a 5-year period.

MAIN OUTCOME MEASURES

Long-term survival of patients with NSCLC after staging by PET.

RESULTS

One hundred fifty-two thoracic PET scans were obtained for the staging of possible NSCLC during a 5-year period. One hundred twenty-three patients (81%) demonstrated increased (18)F-fluorodeoxyglucose uptake. The overall sensitivity and specificity of PET for detecting malignancy were 95% and 67%, respectively, compared with 100% and 27% for chest CT. PET and CT had similar accuracy for staging the overall extent of disease (91% and 89%, respectively). PET stage correlated highly with survival using either nodal location or overall stage (p = 0.003, p = 0.002), as did pathologic staging (p = 0.0001, p = 0.0001). CT scan results did not accurately predict survival (p = 0.608, p = 0.338).

CONCLUSION

PET scanning is a highly sensitive technologic advance in detecting and staging of thoracic malignancy and may more accurately predict the likelihood of long-term survival in patients with NSCLC than chest CT does.

Pulmonary cryptococcosis in the immunocompetent host. Therapy with oral fluconazole: a report of four cases and a review of the literature

Isolated pulmonary cryptococcosis (IPC) is an infrequently diagnosed infection, the management of which is not well defined. In past years, IPC traditionally has not been treated in the immunocompetent host, given its perceived benign and self-limited course and the toxicity associated with amphotericin B. However, some patients manifest prominent and disabling symptoms, and infection occasionally may disseminate. Fluconazole is active against Cryptococcus neoformans, is easily administered, and has an excellent safety profile. We present four healthy hosts with IPC who were treated with oral fluconazole for 6 to 8 weeks. A review of the literature was conducted to identify other cases of IPC in healthy hosts who were also treated with fluconazole. Our results and the limited experience reported in the literature suggest that fluconazole may be an appropriate choice for the treatment of IPC in the immunocompetent host. Indications for treatment are not defined, but symptomatic patients, those with multiple nodules or extensive infiltrates on chest radiographs, and/or those testing positive for serum cryptococcal antigen might be potential candidates for therapy.

Effectiveness of a croup clinical pathway in the management of children with croup presenting to an emergency department

OBJECTIVE

The aim of this study was to evaluate the safety and effectiveness of a clinical pathway for croup in an emergency department (ED).

METHODOLOGY

This before-and-after intervention study on all consecutive children aged 6 months to 10 years who presented to our ED with moderate/severe croup was conducted over a 6-month period. Children with a clinical croup score (CSS) of 2 or more and resting stridor were considered eligible for entry into the study. Children were treated with either oral dexamethasone, or a combination of oral dexamethasone suspension and nebulized adrenaline. Children were clinically assessed, observed in the emergency short-stay ward and discharged or admitted according to the clinical pathway. The following outcomes were measured: admission rates, hospital re-presentation, length of stay, and adverse clinical events. Children in the post-intervention group were followed up by telephone within 48 h of discharge.

RESULTS

There were 157 patients recruited in the pre-intervention group and 110 in the post-intervention group. Significant reductions were reported in the length of stay (18.9 h compared with 5.2 h), hospital admission (52.9% compared with 18.0%) and intensive care admission (10.2% compared with 0.0%) after the introduction of the croup clinical pathway. No children in the study experienced an adverse clinical event. Follow-up interviews of parents indicated that the new treatment strategy was well received.

CONCLUSION

The use of the croup clinical pathway in the ED is safe and effective in guiding consistent management, resulting in reduced admission rates, earlier discharge home, and no reported adverse events.

Oropharyngeal cancer in the elderly

PURPOSE

The poor prognosis of elderly patients in many cancers may be due to less thorough investigation and less aggressive treatment because of the perception that radical treatment will be poorly tolerated and that elderly patients have a limited life expectancy. We wished to assess whether older age is associated with (a) less radical treatment, (b) poorer outcome, or (c) greater toxicity, after adjusting for other possible contributing factors.

METHODS AND MATERIALS

A retrospective study of patients with loco-regional oropharyngeal cancer treated between January 1980 and December 1985 was conducted. Patients were treated with radiotherapy, surgery, chemotherapy, or combinations. Cox regression was used to assess age effects while allowing for the influence of other factors.

RESULTS

Eighty-eight patients were treated radically and 16 palliatively. Treatment intent (radical or palliative) did not appear to be related to age, before (p = 0.42) or after adjusting for other factors (p = 0.34). In a selected group of 86 radically treated patients ages ranged from 33 to 85 (median 60). There were 35 loco-regional failures and 58 deaths (38 related to oropharyngeal cancer). Older patients were prescribed and received lower doses of radiation. However, older age was not related to the risk of loco-regional recurrence (p = 0.96) or shorter survival (p = 0.67), and was not associated with duration of treatment interruption or severity of toxicity after adjustment for prognostic factors. There was some suggestion of a higher risk of recurrence with increasing age for patients under 70 years but with a risk for patients over 70 at least equal to that of the youngest group. Elderly patients in our study may have been a selected group.

CONCLUSION

Older patients with loco-regional oropharyngeal cancer, or at least a subset of them, appear to be able to tolerate radical courses of radiotherapy, and to have similar outcomes as do younger patients.

Sustained expression of high levels of human factor IX from human cells implanted within an immunoisolation device into athymic rodents

Immunoisolation of allogeneic cells within a membrane-bound device is a unique approach for gene therapy. We employed an immunoisolation device that protects allograft, but not xenograft, cells from destruction, to implant a human fibroblast line (MSU 1.2) in athymic rodents. Cells, transduced with the MFG-human factor IX retroviral vector, and expressing 0.9 microg/10(6) cells/day in vitro, were implanted in rats (four 40-microl devices, each containing 2 x 10(7) cells, two subcutaneously, two in epididymal fat) and in mice (two 20-microl devices, each containing 2 x 10(6) cells, subcutaneously). Plasma factor IX levels increased for 50 days, reaching maxima of 203 ng/ml (rat) and 597 ng/ml (mouse), and both continued at greater than 100 ng/ml for more than 140 days. A clone derived from the transduced cells, making 5 microg of factor IX/10(6) cells/day, was implanted within a device (one 20-microl device containing 2.5 x 10(6) cells), or without a device (1 x 10(7) cells implanted freely), either subcutaneously or in epididymal fat. The freely implanted cells expressed transiently, reaching more than 100 ng/ml in each site by day 4, but dropped to zero by day 20 (subcutaneous) or day 90 (epididymal fat). In devices, levels gradually increased to 100 ng/ml (subcutaneous) or 300 ng/ml (epididymal fat), remaining high for more than 100 days. These results show long-term, high-level expression of a human protein: (1) when cells are implanted within a cell transplantation device, but not when the cells are freely implanted, and (2) from a transgene driven by a viral promoter. An alloprotective device will enable the use of cloned cell lines that can be subjected to stringent quality control assessment that is impossible to achieve with autologous approaches.

Hemoptysis: clinicians' perspectives

Clinicians who were interested and considerably experienced in assessing patients with hemoptysis were surveyed during a computer-assisted interactive presentation at the 1988 ACCP Annual Scientific Assembly. The approach to ambulatory patients with minor bleeding was consistent with recently published guidelines: fiberoptic bronchoscopy has a central role, with a less apparent impact of other new technologies. Although specific diagnostic results were significantly more useful (p less than 0.01), even nonspecific bronchoscopy findings were though to have clinical value. External factors such as medicolegal concerns and obligations to provide service were acknowledged to influence selection of patients for bronchoscopy, and community-based clinicians cited such effects more often than academicians (p less than 0.02). Approaches to patients with massive hemoptysis reflected caution essential to acute management. Bronchoscopy was performed earlier (p less than 0.01) than in patients with minor bleeding, but opinions differed regarding instrument selection, the best method of airway support, and the roles of interventional angiography. This survey suggests that real-world settings are addressed incompletely by published experiences accumulated in tertiary centers. Clarification of optimum approaches to patients with hemoptysis requires further input from practicing clinicians.

Clinical associations of anosognosia in mild cognitive impairment and Alzheimer's disease

AIMS AND OBJECTIVE

While loss of insight of cognitive deficits is a common phenomenon in patients with Alzheimer's disease (AD), there is a lack of consensus regarding the presence of impaired insight among patients with mild cognitive impairment (MCI). We aim to investigate the clinical, cognitive, and behavioral associations of anosognosia in AD and MCI subjects.

METHODS

A consecutive series of 87 subjects (30 healthy older patients, 21 MCI, and 36 AD) each accompanied by a caregiver, underwent clinical assessment including the evaluation of insight using the Anosognosia Questionnaire for Dementia (AQD). We also separately assessed Intellectual Function (AQD-IF) and Behavior domains of the AQD scale. Regression models were subsequently used to investigate associations of AQD scores with cognitive and other neuropsychiatric symptoms, including depression and apathy.

RESULTS

Both AD and MCI groups demonstrated significant anosognosia compared with the healthy control group. In the AD group, 55.6% had "Mild Anosognosia," and 27.8% had "Severe Anosognosia." In the MCI group, 42.9% showed "Mild Anosognosia," and 9.5% had "Severe Anosognosia." Greater levels of AQD-Total and AQD-IF were associated with lower Mini-mental state examination and higher apathy scores in the AD group. In the MCI group, caregiver burden was significantly associated with AQD-Total (p = 0.016) and AQD-IF (p = 0.039).

CONCLUSION

The results indicated that anosognosia is common in both AD and MCI patients and associated with cognitive dysfunction and apathy in AD. The findings of this study warrant further research to delineate the mechanisms of anosognosia as it poses a challenge to treatment outcomes.

Baseline oxygen saturation predicts exercise desaturation below prescription threshold in patients with chronic obstructive pulmonary disease

BACKGROUND

Recent studies of exercise-induced hypoxemia in patients with chronic obstructive pulmonary disease (COPD) have shown that oxygen supplementation during exertion increases exercise tolerance and alleviates dyspnea. Although measurements of forced expiratory volume in 1 second and diffusion capacity for carbon monoxide (DLCO) are known to predict exercise-induced desaturation in patients with COPD, baseline oxygen saturation has never been studied as a predictor of exercise-induced desaturation.

METHODS

A retrospective analysis was performed of 100 consecutive patients with forced expiratory volume in 1 second-forced vital capacity ratio of 70% or less who underwent exercise testing for desaturation. Any desaturation to 88% or less with exercise was considered significant. Nineteen patients with total lung capacity of 80% or less were excluded to avoid evaluating those with combined obstructive and restrictive defects; 81 patients remained available for study.

RESULTS

Nineteen (51%) of 37 patients with resting saturation of 95% or less desaturated with exercise as opposed to 7 (16%) of 44 with resting saturation of 96% or greater (P =.001). The sensitivity and the negative predictive value of baseline saturation of 95% or less as a screening test for exercise desaturation were 73% and 84%, respectively. If all patients with DLCO of 36% or less were excluded, 40 patients were left for study. Eight (40%) of 20 patients with baseline saturation of 95% or less compared with 0 of 20 with resting saturation of 96% or greater desaturated with exercise (P =.006). In this subset, the sensitivity and the negative predictive value of baseline saturation of 95% or less as a screening test for exercise desaturation both improved to 100%.

CONCLUSIONS

In patients with COPD, baseline saturation of 95% or less is a good screening test for exercise desaturation, especially in patients with DLCO greater than 36%. This readily available office screening procedure merits further study in larger prospective patient cohorts.

Direct sequencing of consensus primer generated PCR fragments of human papillomaviruses

Consensus primers specific for the L1 and E1 regions were used to amplify HPV DNA fragments. These fragments were then directly sequenced using the consensus primers as the sequencing primers. The linking of PCR amplification, direct sequencing, and computer data bank analysis provides a new approach in the detection of different HPVs and has several advantages over existing methodology. These advantages include increased precision in the rapid characterization of known HPVs, detection of mutations, and identification of new HPV types.

Evidence for the production and action of interleukin-10 in pituitary cells

1. Interleukin-10 (IL-10) has a wide range of activities in the immune system such as modulation of interferon-gamma (IFN-gamma) and antibody production. The neuropeptide hormone corticotropin (ACTH) has similar activities, suggesting that a bidirectional communication mechanism operates between the immune and the neuroendocrine system involving these two substances. 2. Murine pituitary tumor cells (AtT-20) were found to produce up to 3 ng/ml of IL-10. 3. Pituitary cell corticotropin production was enhanced by IL-10 treatment. 4. IL-10 induced the production of ACTH in mouse splenocytes. 5. Authenticity of pituitary-derived IL-10 was shown by the demonstration of identical nucleic acid sequences of reverse-transcribed, polymerase chain reaction amplified fragments of cDNA obtained from murine splenocytes, a murine pituitary tumor cell line, and freshly isolated murine pituitaries.

Thoracobiliary fistula

Thoracobiliary communications in the form of either pleurobiliary or bronchobiliary fistulas are reported complications of many diseases. A strong suspicion in the appropriate clinical setting is necessary to recognize this problem. Bilioptysis is the sine qua non of a bronchobiliary fistula. Diagnostic imaging studies are useful to identify the communication and to delineate its location. Although surgery is the optimal intervention, percutaneous drainage and intravenous antimicrobial therapy may offer the best therapeutic option in patients with metastatic cancer and limited physiologic reserve. We report a unique case of bronchobiliary fistula complicating a uterine leiomyosarcoma with hepatic metastases. Long-term palliation was achieved with percutaneous drainage and appropriate fluid and electrolyte replacement therapy.

Chronic antigen-specific immune-system activation may potentially be involved in the loosening of cemented acetabular components

Previous studies have attempted to determine whether aseptic loosening and osteolysis are caused by a T cell-mediated type IV hypersensitivity reaction or a nonspecific foreign body reaction involving phagocytic macrophages. The purpose of this study was to examine the role of the B7-CD28 costimulatory pathway (which is indicative of an activated immune response) in loosening and osteolysis of total joint replacements (TJRs). We harvested periprosthetic tissues from 24 loose, cemented, all polyethylene, acetabular components in patients undergoing revision total hip replacement surgery for aseptic loosening. Prostheses were classified radiographically as to whether ballooning, scalloping osteolysis was present or not. Monoclonal antibodies were used to identify macrophages, antigen presenting cells (APCs) expressing B7-1 or B7-2, total T lymphocytes, and T cells expressing CD28 or CTLA-4. The large numbers of positive cells, including macrophages, T cells, and APCs in both groups are substantially higher than previously reported. Macrophages constituted the predominant cell type, the majority of which were APCs. B7-1 was expressed by 18.3% of all cells, and B7-2 was expressed by 61.0% of cells. Despite the fact that there were no statistically significant differences in expression of proteins in the B7-CD28 pathway between the osteolytic and nonosteolytic groups, the magnitude of positive staining suggests that the process of aseptic loosening (not osteolysis) may involve proteins of the B7-CD28 pathway, particularly B7-2. One possible antigenic stimulus is protein-coated particulate wear debris from prosthetic materials.

Fiberoptic bronchoscopy in coronary care unit patients: indications, safety, and clinical implications

STUDY OBJECTIVES

To evaluate the indications, safety, therapeutic impact, and outcome of fiberoptic bronchoscopy (FOB) in coronary care unit (CCU) patients.

DESIGN

Retrospective review of all CCU patients undergoing FOB during a 6-year period.

SETTING

Tertiary care university hospital.

RESULTS

Among 8,330 patients admitted to the CCU; 40 (0.5%) patients underwent FOB to evaluate pulmonary abnormalities, most often (78%) to appraise clinically suspected pneumonia. Thirty-five (88%) patients were intubated and 21 (53%) had acute myocardial infarction (MI) before FOB. There were two major complications (bleeding, intubation) occurring within 24 h of FOB, one of which appeared due to the procedure. No episodes of chest pain or ischemic events were recorded and no significant increase in major complications was noted in MI patients (3% vs 5%). Patients having FOB within 10 days of MI had higher survival (79%) than those undergoing FOB later (29%) (p = 0.05). Seven different bacterial pathogens were isolated in 6 (15%) patients, probably reflecting prior empiric antibiotics in 32 (80%) patients. Therapy was changed in 64% of patients in whom a potential pathogen was identified. Despite alterations in treatment, patients with clinically suspected pneumonia and any organisms isolated by FOB had greater mortality (79% vs 31%, p = 0.003) than those with sterile FOB cultures.

CONCLUSION

FOB may be diagnostically useful in the evaluation of pulmonary abnormalities in selected patients with acute cardiac disease, can be performed safely, and may influence management decisions. Positive bronchoscopy cultures often influence therapy but are associated with higher mortality, suggesting a lethal effect of nosocomial pneumonia in this subset of CCU patients. The risks of FOB must be weighed with the impact of FOB results on patient outcome, and its role requires further investigation.

Characterization of a hepatitis C virus-like particle vaccine produced in a human hepatocyte-derived cell line

An effective immune response against hepatitis C virus (HCV) requires the early development of multi-specific class 1 CD8+ and class II CD4+ T-cells together with broad neutralizing antibody responses. We have produced mammalian-cell-derived HCV virus-like particles (VLPs) incorporating core, E1 and E2 of HCV genotype 1a to produce such immune responses. Here we describe the biochemical and morphological characterization of the HCV VLPs and study HCV core-specific T-cell responses to the particles. The E1 and E2 glycoproteins in HCV VLPs formed non-covalent heterodimers and together with core protein assembled into VLPs with a buoyant density of 1.22 to 1.28 g cm-3. The HCV VLPs could be immunoprecipited with anti-ApoE and anti-ApoC. On electron microscopy, the VLPs had a heterogeneous morphology and ranged in size from 40 to 80 nm. The HCV VLPs demonstrated dose-dependent binding to murine-derived dendritic cells and the entry of HCV VLPs into Huh7 cells was blocked by anti-CD81 antibody. Vaccination of BALB/c mice with HCV VLPs purified from iodixanol gradients resulted in the production of neutralizing antibody responses while vaccination of humanized MHC class I transgenic mice resulted in the prodution of HCV core-specific CD8+ T-cell responses. Furthermore, IgG purified from the sera of patients chronically infected with HCV genotypes 1a and 3a blocked the binding and entry of the HCV VLPs into Huh7 cells. These results show that our mammalian-cell-derived HCV VLPs induce humoral and HCV-specific CD8+ T-cell responses and will have important implications for the development of a preventative vaccine for HCV.

Sexual behavior in pregnancy among Hong Kong Chinese women

Sexual behavior during pregnancy was examined in a retrospective study of 150 Hong Kong Chinese women interviewed in the immediate postpartum period. Sexual activity was found to decline abruptly during the first trimester of pregnancy, and continued to decrease in frequency as the pregnancy advanced. The frequency of intercourse was lower both before and during pregnancy than has been reported in similar studies among Western populations. There was no consistent relationship between age, parity, level of education, or employment status and sexual behavior either before or during pregnancy. These results suggest that a relatively conservative attitude toward sexual activity persists within this population.

The HLA-DR2 haplotype is associated with an increased proliferative response to the immunodominant CD4(+) T-cell epitope in human interferon-beta

Human CD4(+) T-cell epitopes were identified in interferon-beta (IFN-beta)-1b. A prominent peptide epitope region was found that induced a proliferative response in 16% of all donors tested. Responses corresponded to the presence of the HLA-DR2 haplotype. Responsive donors expressing the HLA-DQ6 allele showed an increased level of proliferation to the epitope as compared to peptide-responsive HLA-DQ6 negative donors. A similar result was found for HLA-DR15-expressing donors. PBMC from donors expressing HLA-DR15 were more likely to proliferate in response to IFN-beta in a whole-protein in vitro assay than donors who did not carry this haplotype. It is striking that the common DQ6 allele HLA-DQB1(*)0602 is found in linkage disequilibrium with HLA-DRB1(*)1501, and this combination defines the HLA genotype associated with the development of multiple sclerosis. The HLA association between a response to IFN-beta and MS might explain the prevalence of neutralizing antibody development, and may underlie the etiology of the disease.

The aluminum content of biological products containing aluminum adjuvants: determination by atomic absorption spectrometry

Aluminum compounds are used as adjuvants in certain types of vaccines, toxoids and allergenic extracts for human use. The most common Al compounds used in biological products to enhance the immune response are aluminum potassium sulphate (alum), aluminum hydroxide and aluminum phosphate. This study describes an atomic absorption spectrometric method for the determination of the Al content of Al adsorbed toxoid preparations and allergenic extracts at levels of less than 0.85 mg of Al per half millilitre human dose. Aliquots of the samples which contained Al suspensions were acid digested with nitric and sulphuric acid and analysed in the nitrous oxide-acetylene flame of an atomic absorption spectrometer. The 396.2 nm Al line was used for analysis. The Al content of the National Bureau of Standards (NBS) Standard Reference Material No. 1075a aluminum 2- ethylhexanoate was determined to within 1% of the NBS certificate value by this method. Atomic absorption results for the Al content of tetanus toxoids containing aluminum potassium sulphate and aluminum phosphate were compared with polarographic and inductively coupled argon plasma (ICP) emission spectrometry results. Reproducibility and recovery data for Al are tabulated for a variety of biological products containing aluminum phosphate, aluminum potassium sulphate and aluminum hydroxide adjuvants. In addition, ICP has been used to characterize the Al and P compositions of the precipitates and supernatant solutions which resulted from centrifuging toxoid suspensions that contained the three different Al adjuvants.

Endobronchial needle aspiration in the diagnosis of small-cell carcinoma

Endobronchial biopsy specimens of small-cell carcinoma often exhibit extensive crush artifact that precludes definitive diagnosis. Occasionally, cytologic study from the brushings and washings is also nondiagnostic, contributing to the frustration of the bronchoscopist. We reviewed our experience with this problem over the past 4 years. We identified five cases in which an endobronchial needle aspirate proved critical in establishing the diagnosis of small-cell carcinoma. We believe endobronchial needle aspiration is a valuable adjunct in the diagnosis of endobronchial small-cell carcinoma.