Immunologic changes after transfusion of autologous or allogeneic buffy coat-poor versus white cell-reduced blood to patients undergoing arthroplasty. I. Proliferative T-cell responses and the balance of helper and suppressor T cells

BACKGROUND

Donor white cells (WBCs) contained in red cell (RBC) transfusions are thought to provoke down-regulation of T-cell-mediated immunity. This study investigated this topic in otherwise healthy patients receiving buffy coat-depleted or WBC-filtered RBCs and undergoing standardized perioperative management.

STUDY DESIGN AND METHODS

Patients undergoing elective orthopedic surgery (primary hip and knee replacement surgery) were enrolled in a prospective study. Perioperative changes in T-cell proliferation (stimulation with phytohemagglutinin and mixed lymphocyte culture) and T-cell balance (T-lymphocytes, helper T cells, and suppressor T cells) were compared after random assignment to allogeneic buffy coat-depleted (Group 2, n = 8) or WBC-reduced RBC (Group 3, n = 11) transfusion regimens. Recipients of autologous buffy coat-depleted RBC transfusions (n = 15) served as controls (Group 1).

RESULTS

Compared to that in autologous transfusion recipients, alloantigen-induced T-cell proliferation was significantly reduced in recipients of allogeneic WBC-reduced RBCs (Day 3, p = 0.0274). After the transfusion of allogeneic buffy coat-depleted RBCs, a weak trend toward decreased T-cell proliferation was observed (p = 0.0933) and the numbers of CD4+ T cells were also significantly lower (Day 7, p = 0.0389). On Day 10, alloantigen-induced T-cell proliferation remained significantly below baseline after transfusion of WBC-reduced RBCs (p = 0.05), the numbers of CD3+ cells decreased in allogeneic RBC recipients (Group 2, p = 0.078; Group 3, p = 0.05), and those of CD8+ cells decreased significantly after the transfusion of allogeneic buffy coat-depleted RBCs (p = 0.0234) concomitant with an increased CD4:CD8 ratio (p = 0.0391).

CONCLUSION

Results of the present study confirm the hypothesis of impaired T-cell-mediated immunity after allogeneic transfusion.

Photoinduced orientation of azo dye in various polymer matrices

Photoinduced dichroism in various polymers containing the same azo dye has been studied. "Angular hole burning" and molecular reorientation have been identified by analysis of dichroism dynamics at various probe wavelengths. The glass-transition temperature T(g) is of major relevance for the reorientation of optically active molecules. For low T(g) (below ambient temperature) thermal diffusion impedes anisotropy buildup. For higher T(g) the angular distribution induced by the polarized pump beam is frozen. We propose a simple model based on diffusion rates in trans and cis molecules.

Temperature effects on the discharge frequency of primary and secondary endings of isolated cat muscle spindles recorded under a ramp-and-hold stretch

The effects of changes in temperature on primary and secondary endings of isolated cat muscle spindles were investigated under ramp-and-hold stretches and different degrees of pre-stretch. Temperature-induced alterations of the discharge frequency were compared over a temperature range of 25-35 degrees C. Both primary and secondary endings responded to warming with increasing discharge frequencies when the spindle was pre-stretched by 5-10% of its in situ length. The following differences between the temperature effects on primary and secondary endings were observed: (1) The temperature coefficients (Q(10)) obtained from the discharge frequencies during the dynamic and static phase of a stretch were similar for endings of the same type, but they were larger in primary endings (range of Q(10): 2.3-3.3; mean: 2.9) than in secondary endings (range of Q(10): 1.6-2.2; mean: 2.0); (2) With primary endings, but not with secondary endings, the temperature sensitivity (imp s(-1) degrees C(-1)) was larger during the dynamic phase than during the static phase of a stretch; (3) In primary endings, the fast and slow adaptive components occurring in the discharge frequency during the static phase of a stretch clearly increased with warming while in secondary endings, the slow decay was less affected, and the fast decay showed no change; (4) In relaxed spindles, the excitatory effect of warming was overlaid by a strong inhibitory effect as soon as the temperature exceeded about 30 degrees C, resulting in an abrupt cessation of the background activity in most secondary endings, but not usually in primary endings. In general, warming induced an enhanced stretch sensitivity in both types of ending, and additionally an inhibitory effect that is obvious only in secondary endings of relaxed spindles. The different effects of temperature on the discharge frequency of primary and secondary afferents are assumed to be caused by different properties of their sensory membranes.

Measurements of bone mineral density. Mineral density in metabolic bone disease

Bone metabolism and thus bone remodelling and bone mineral content are profoundly influenced by many hormonal and metabolic factors. This review presents the state of the art procedures for bone mineral absorptiometry and examines the interactions of endocrine and metabolic diseases and bone mineral content. Preventive and therapeutic modalities of osteoporosis are discussed in this context.

Transcutaneous electrical nerve stimulation as an adjunct for controlling chemotherapy-induced nausea and vomiting in gynecologic oncology patients

BACKGROUND

To evaluate the efficacy of a miniaturized portable transcutaneous electrical nerve stimulation (TENS) unit (ReliefBand) as an adjunct to standard antiemetic therapy for controlling nausea and vomiting induced by cisplatin-based chemotherapy in gynecologic oncology patients.

METHODS

Forty-two patients were enrolled in a randomized, double-blind, placebo-controlled parallel-subjects trial with a follow-up crossover trial. All patients received a standardized antiemetic protocol, then wore the ReliefBand continuously for 7 days.

RESULTS

Thirty-two patients were evaluable for the parallel-subjects component, 16 in each group. The percentage of patients with absent or minimal nausea was 59% overall, which was similar to that for both the active (56%) and placebo (62%) groups. The incidence and severity of nausea and vomiting was similar for each group. Eighteen patients completed two consecutive cycles and were evaluable for the crossover component. The average age of the crossover patients and their dose intensity were comparable with those of the overall study population (56.3 versus 58.6 years and 22.7 versus 22.7 mg/m2/week, respectively). The percentage of cycles with absent or minimal nausea was 47% overall, which was similar to that of the active (50%) and placebo (44%) cycles. However, the severity of nausea was significantly lower in the active cycles during days 2 to 4. Patients averaged less than one episode of vomiting daily in each cycle.

CONCLUSIONS

The ReliefBand is an effective adjunct to standard antiemetic agents for controlling nausea induced by cisplatin-based chemotherapy in gynecologic oncology patients.

Volvoxrhodopsin, a light-regulated sensory photoreceptor of the spheroidal green alga Volvox carteri

Somatic cells of the multicellular alga Volvox carteri contain a visual rhodopsin that controls the organism's phototactic behavior via two independent photoreceptor currents. Here, we report the identification of an opsinlike gene, designated as volvoxopsin (vop). The encoded protein exhibits homologies to the opsin of the unicellular alga Chlamydomonas reinhardtii (chlamyopsin) and to the entire animal opsin family, thus providing new perspectives on opsin evolution. Volvoxopsin accumulates within the eyes of somatic cells. However, the vop transcript is detectable only in the reproductive eyeless gonidia and embryos. vop mRNA levels increase 400-fold during embryogenesis, when embryos develop in darkness, whereas the vop transcript does not accumulate when embryos develop in the light. An antisense transformant, T3, was generated. This transformant produces 10 times less volvoxopsin than does the wild type. In T3, the vop transcript is virtually absent, whereas the antisense transcript is predominant and light regulated. It follows that vop expression is under light-dependent transcriptional control but that volvoxopsin itself is not the regulatory photoreceptor. Transformant T3 is phototactic, but its phototactic sensitivity is reduced 10-fold relative to the parental wild-type strain HK10. Thus, we offer definitive genetic evidence that a rhodopsin serves as the photoreceptor for phototaxis in a green alga.

Alendronate increases bone density and bone strength at the distal radius in postmenopausal women

In addition to the alendronate Osteoporosis Intervention Trial (FOSIT) core protocol 901-0A of 1908 enrolled patients, the use of peripheral quantitative computed tomography (pQCT) was explored for the assessment of response to therapy. Bone mineral and strength related parameters at two different sites at the distal radius were explored in a subset of the multicenter core study. One hundred and three patients were entered into the substudy and given either a daily dose of 10 mg of alendronate or placebo for 1 year. Measurements were done at months 0, 3, 6, and 12. Inclusion criteria were bone mineral density (BMD) measurements at the lumbar spine of -2 SD. The response to therapy was assessed by dual-energy X-ray absorptiometry in the lumbar spine and the hip, and by pQCT in the ultradistal and the shaft sites of the radius. In line with the FOSIT core study, alendronate increased BMD at the lumbar spine and the hip, and it decreased the serum biochemical markers of bone turnover. The substudy showed differences between the therapy and placebo group in trabecular bone density (8.4%, p = 0.095), in total density (6.8%, p = 0.009), and in the bone strength index (BSI) (15. 6 mm3, p = 0.037) at the ultradistal site due to treatment and no changes at the radius shaft. A significant correlation was observed between percentage changes from baseline in BMD of the lumbar spine, and in total density and bone strength at the ultradistal radius site in the treatment group, but not in the placebo group. Thus, the ultradistal radius site did respond to alendronate therapy. The increased bone density accompanied a significant gain in the BSI at the ultradistal site, a finding that might help explain the reduced wrist fractures in the alendronate Fracture Intervention Trial.

Are cumulus cells necessary for the spontaneous maturation of germinal vesicle-stage oocytes to metaphase II

PURPOSE

In this study we investigated the need of the support from cumulus cells for germinal-vesicle (GV) oocytes collected from stimulated ovaries to complete their maturation to metaphase II (MII).

METHODS

We compared the maturation rate of GV oocytes after coculture with cumulus cells (study group) with their spontaneous maturation in culture medium alone (control group).

RESULTS

Sixty-four and nine-tenths percent of the GV oocytes matured to metaphase II in the coculture group, and of these, 43.5% gave normal 2pn zygotes following intracytoplasmic sperm injection (ICSI), while 73.8% of the GV oocytes spontaneously matured to the MII stage and 30% of these reached the zygote stage after ICSI.

CONCLUSIONS

It is probable that a follicular factor is responsible for this arrested maturation in the human and that maturation occurs spontaneously when the oocytes are separated from their follicular fluid environment after collection.

Resuscitation in Europe: a tale of five European regions

AIM

To describe cardiac arrest data from five emergency medical services (EMS) systems in Europe with regard to survival from an out-of-hospital cardiac arrest.

METHODS

Based on recommendations from various countries in Europe EMS systems were approached with regard to survival from out-of-hospital cardiac arrest. Five EMS systems were asked to report their cardiac arrest data according to the Utstein style.

RESULTS

The five selected EMS systems were: Bonn (Germany), Göttingen (Germany), Helsinki (Finland), Reykjavik (Iceland) and Stavanger (Norway). For patients with a bystander witnessed arrest of cardiac aetiology the percentage of patients being discharged alive from hospital in these regions were: 21, 33, 23, 23 and 35. The corresponding percentages for patients fulfilling criteria as above and being found in ventricular fibrillation were: 32, 42, 32, 27 and 55.

CONCLUSIONS

Many EMS systems in Europe show extremely good results in terms of survival after an out-of-hospital cardiac arrest. Some of the results should be interpreted with caution since they were based on relatively small sample sizes. Furthermore, the results from one of the regions (Stavanger) was unit based and not community based.

[Radiation-induced morphea]

Although the aetiology of morphea often remains unknown, various precipitating causes have been identified. Morphea is a rare development following irradiation. We observed a circumscribed scleroderma 14 years after x-ray-radiotherapy following surgery of breast cancer. Furthermore multiple weeping papules occurred within the radiation area. A relapse of the breast cancer was ruled out by histological examination which displayed a transepidermal elimination of acid mucin. The irradiation had obviously induced different reactions of the dermal fibroblasts (radiodermatitis, morphea, mucin production).

Venous thromboembolism at a young age in a brother and sister with coinheritance of homozygous 20210A/A prothrombin mutation and heterozygous 1691G/A factor V Leiden mutation

We report on members of a Turkish thrombophilic family with coinheritance of the prothrombin mutation PT20210A and the factor V Leiden mutation. The 23-year-old propositus and his elder sister both had episodes of venous theomboembolism at a young age (23 years and 26 years, respectively) and are homozygous for the PT20210A mutation and heterozygous for the factor V Leiden mutation. The 51-year-old father is suffering from coronary heart disease and is heterozygous for both thrombophilic mutations. The asymptomatic 43-year-old mother is heterozygous for the PT20210A mutation, but without activated protein C resistance. Two other children, a 20-year-old girl who is homozygous for the PT20210A mutation and a 13-year-old boy who is heterozygous for the PT20210A mutation, are both free from activated protein C resistance and thrombosis. This report provides further evidence for an early onset of thromboembolic disorders in individuals with an homozygous state of the prothrombin variant 20210A/A and coinheritance of another thrombophilic mutation. Consensus guidelines are required for the treatment and prophylaxis of patients and subjects who remain asymptomatic with homozygous or more than one heterozygous genetic defect associated with thrombophilia.

Investigation of solid-phase peptide synthesis by the near-infrared multispectral imaging technique: a detection method for combinatorial chemistry

A near-infrared (NIR) multispectral imaging spectrometer was used to monitor solid-phase peptide synthesis. This imaging spectrometer has fast scanning ability and high sensitivity because it is based on an acousto-optic tunable filter and a NIR InGaAs focal plane array camera. This NIR imaging instrument possesses all the advantages of conventional NIR spectrometers; namely, it can be used for noninvasive monitoring of the reactions and identification of the products during the solid-phase peptide synthesis of glycine, alanine, and valine mediated by aminomethylstyrene resin beads. The reaction was determined by monitoring either the decrease of the band at 1529 nm, which is due to the amine group on the beads, or the increase of the amide band generated at 1483 nm. The amine band at 1529 nm was also used to determine the presence of the Fmoc protecting groups and the efficiency of its removal. More importantly, this NIR imaging spectrometer has additional features that conventional NIR spectrometers cannot offer; namely, its ability to measure spectra at different positions within a sample. This feature was utilized for the first demonstration in which reactions of three different solid-phase peptide syntheses (in a three-compartment cell) were simultaneously monitored. As expected, the kinetics obtained for three reactions are similar to those obtained when the each of the reactions was individually determined. In this study, data recorded by 16 x 16 pixels were used to calculate a spectrum for each sample. However, a relatively good spectrum can be obtained by using data recorded by a single pixel. Since the NIR camera used in this camera is equipped with 240 x 320 pixels, this NIR mutispectral imaging technique is not limited to the three-compartment cell used in this study but rather can be used as the detection method for the solid-phase peptide synthesis in combinatorial chemistry.

A role for the immunoglobulin-like domain of the human IL-6 receptor. Intracellular protein transport and shedding

Interleukin (IL)-6, IL-11 and cililary neurotrophic factor (CNTF) belong to the same family of hematopoietic and neurotrophic cytokines. Their receptor complexes contain a cytokine-binding alpha receptor and the common glycoprotein (gp)130 subunit for signal transduction. The extracellular parts of the alpha-receptor subunits consist of a membrane-proximal cytokine-binding domain and an N-terminal immunoglobulin (Ig)-like domain with unknown function. We examined the role of the Ig-like domain of IL-6R by constructing deletion mutants lacking the Ig domain (IL-6RDeltaIg and soluble IL-6RDeltaIg). IL-6RDeltaIg was shed as effectively as wild-type IL-6R from transfected COS-7 cells upon 4beta-phorbol 12-myristate 13-acetate (PMA) treatment, whereas nonstimulated shedding of IL-6RDeltaIg was not observed. The shed sIL-6RDeltaIg from PMA-treated cells, as well as the transmembrane IL-6RDeltaIg, had the same biological activity as wild-type sIL-6R, as measured by the induction of haptoglobin secretion in HepG2-IL-6 cells and IL-6-dependent proliferation of IL-6RDeltaIg transfected BAF/gp130 cells. In COS-7 cells transfected with IL-6RDeltaIg or soluble IL-6RDeltaIg cDNA, transport of the deletion mutants through the secretory pathway appeared to be delayed because a sizeable proportion of the mutants was detected as an endo-beta-N-acetylglucosaminidase-sensitive intermediate, suggesting that transport and processing of the DeltaIg mutants on the secretory pathway were impaired. These experiments suggest that the Ig-like domain of the IL-6R is important for intracellular transport of IL-6R through the secretory pathway. Furthermore, the Ig-like domain is necessary for noninduced shedding of the IL-6R, whereas it has no function in PKC-dependent shedding of the IL-6R.

Histidine 179 mutants of GTP cyclohydrolase I catalyze the formation of 2-amino-5-formylamino-6-ribofuranosylamino-4(3H)-pyrimidinone triphosphate

GTP cyclohydrolase I catalyzes the conversion of GTP to dihydroneopterin triphosphate. The replacement of histidine 179 by other amino acids affords mutant enzymes that do not catalyze the formation of dihydroneopterin triphosphate. However, some of these mutant proteins catalyze the conversion of GTP to 2-amino-5-formylamino-6-ribofuranosylamino-4(3H)-pyrimidinone 5'-triphosphate as shown by multinuclear NMR analysis. The equilibrium constant for the reversible conversion of GTP to the ring-opened derivative is approximately 0.1. The wild-type enzyme converts the formylamino pyrimidine derivative to dihydroneopterin triphosphate; the rate is similar to that observed with GTP as substrate. The data support the conclusion that the formylamino pyrimidine derivative is an intermediate in the overall reaction catalyzed by GTP cyclohydrolase I.

Cervical cancer screening among Cambodian-American women

Southeast Asian women have higher invasive cervical cancer incidence rates and lower Pap testing frequencies than most other racial/ethnic groups in the United States. However, there is little information about the cervical cancer screening behavior of Cambodian-American women. Cambodian residents of Seattle were surveyed in person during late 1997 and early 1998. The PRECEDE model was used to guide the development of items that assessed predisposing, reinforcing, and enabling factors associated with cervical cancer screening participation. The estimated overall survey response was 72%. Four hundred thirteen women completed our questionnaire. Approximately one-quarter (24%) of the respondents had never had a Pap test, and over one-half (53%) had not been screened recently. The following variables were positively associated with a history of at least one Pap smear: younger age, greater number of years since immigration, belief about Pap testing for postmenopausal women, prenatal care in the United States, and physician recommendation. Women who believed in karma were less likely to have ever been screened for cervical cancer than those who did not. Six variables independently predicted recent screening: age; beliefs about regular checkups, cervical cancer screening for sexually inactive women, and the prolongation of life; having a female doctor; and a previous physician recommendation for Pap testing. The study findings indicate that culturally specific approaches might be effective in modifying the cervical cancer screening behavior of immigrant women. Programs targeting Cambodian-Americans are likely to be more effective if they are multifaceted and simultaneously address predisposing, reinforcing, and enabling factors.

Neisseria meningitidis serogroup B outer membrane vesicle vaccine in adults with occupational risk for meningococcal disease

Vaccination provides a safe and effective means of reducing the risk of laboratory-acquired infection due to some Neisseria meningitidis serogroups. However, there is currently no serogroup B meningococcal vaccine licensed for use in the US. We used an investigational N. meningitidis serogroup B outer membrane vesicle (B:15:P1.7,16) vaccine produced by the National Institute of Public Health (NIPH) in Norway to immunize 20 researchers with occupational risk for disease. Three doses of vaccine were administered via intramuscular injection at 8-week intervals. The vaccine produced moderate or severe pain with 19 (33%) of the 58 doses administered. Reactions were similar following first, second and third doses. The number and severity of reactions peaked at 24 h postvaccination and then gradually waned. Of 16 vaccinees with results available from all blood draws, 12 (75%) showed a fourfold or greater rise in serum bactericidal activity (SBA) against the vaccine type-strain following two doses of vaccine, and 15 (94%) responded after three doses. Geometric mean titers increased by more than sixfold following two doses of vaccine when compared with prevaccination levels, and by more than 11-fold following a third dose. There was no significant difference between SBA measured using the vaccinee's own complement versus a donor complement source. The NIPH vaccine elicited an excellent bactericidal response against the vaccine type-strain in researchers with an occupational risk for disease. It may be useful for other laboratory personnel who routinely work with meningococcal strains containing similar outer membrane antigens. These findings reconfirm that the NIPH vaccine is immunogenic in adults and support the validity of using properly screened human donor complement in serum bactericidal assays against serogroup B meningococci.

Highly sensitive methods for quantitation of human immunodeficiency virus type 1 RNA from plasma, cells, and tissues

Precise and sensitive quantitation of viral RNA in specimens from human immunodeficiency virus (HIV) type 1 (HIV-1)-infected individuals has become an indispensable tool for the monitoring of the efficacy of highly active antiretroviral combination therapy. The present report describes reproducible and efficient protocols with enhanced sensitivity for quantitation of HIV-1 RNA from plasma, peripheral blood mononuclear cells, and tissues with Qiagen silica columns for RNA purification combined with the Roche Amplicor HIV-1 Monitor test for quantitative reverse transcription-PCR (RT-PCR). Extraction of RNA from 0.5 ml of plasma resulted in the detection of fewer than 20 HIV RNA copies/ml of plasma, equivalent to the centrifugation-based boosted RT-PCR assay. Silica extraction of cellular RNA resulted in the detection of fewer than 3 HIV-1 RNA copies/microg of total RNA. These techniques facilitate direct comparisons of viral loads between liquid and cellular specimens. Application of these sensitive methods may improve the assessment of the response to new antiretroviral regimens.

Correlation between coronary morphology and molecular markers of fibrinolysis in unstable angina pectoris

BACKGROUND

In acute coronary syndromes, marked alterations of coagulation and fibrinolysis have been observed, but no data are available concerning a possible relation to coronary stenosis morphology.

METHODS

Thirty one patients with unstable angina pectoris were included. Culprit stenosis morphology judged from coronary angiography was graded using the modified ACC/AHA classification. Molecular and functional markers of hemostasis and fibrinolysis were determined from venous plasma samples obtained at admission.

RESULTS

Patients with unstable angina pectoris had a moderate procoagulant state, especially a contact phase activation compared with age-matched controls (factor XII 93.9 +/- 5.6 vs 112.8 +/- 5.4%; P < 0.05; high molecular weight kininogen 55.3 +/- 5.4 vs 86.1 +/- 6.5%; P < 0.01). Thrombin-antithrombin (TAT) was not significantly elevated (7.6 +/- 1.9 vs 4.0 +/- 0.5 microg/l). Elevated plasminogen activator mass concentration (16.6 +/- 2.1 vs 5.4 +/- 0.6 ng/ml; P < 0.01) and plasminogen activator inhibitor (PAI) activity (9.9 +/- 3.0 vs 5.6 +/- 3.0 AU/ml; P < 0.05) indicated an alteration of the fibrinolysis. Complexity of coronary stenosis was positively correlated with tissue-type plasminogen activator (TPA) mass concentration (P < 0.01) and PAI activity (P < 0.05). No association was found to markers of a hypercoagulative state.

CONCLUSION

These findings indicate a relation between alterations of the fibrinolytic system and coronary morphology, whereas the acute changes of coagulation occur independently of culprit stenosis complexity.

[Peritoneal mesothelioma--incidence and etiology]

A total of 70 malignant and 4 benign peritoneal mesotheliomas were diagnosed by the German Mesothelioma Registry between 1992 and 1998. Malignant mesotheliomas developed mainly in men (55/70); only one man had a benign peritoneal alteration. Age at first diagnosis of malignant mesotheliomas is about 59 years; the women are on average 4 years younger than the men. Mean survival time ranges about 1 year; in 6 of 38 patients longer survival times of up to 7 years are known. The epitheloid subtype predominates, but no effect on survival time is noticed. The percentage of patients with combined asbestos-associated lung fibrosis is higher than that for pleural mesotheliomas; these patients become ill about 6.5 years earlier. The latency period is 36 years on average. For most patients asbestos exposure is related to their occupation mainly in metal industries, asbestos industries, and in the building trade. There is no evidence for an induction of benign peritoneal alterations by asbestos dust.

Epidemic serogroup B meningococcal disease in Oregon: the evolving epidemiology of the ET-5 strain

CONTEXT

In 1993, Oregon's incidence of serogroup B meningococcal disease began to rise because of a highly clonal group of strains designated enzyme type 5 (ET-5), the first such increase observed in the United States.

OBJECTIVE

To evaluate the impact that the ET-5 strain has had on the epidemiology of meningococcal disease in Oregon.

DESIGN AND SETTING

Epidemiologic analysis of surveillance data on Oregon meningococcal disease cases from 1987 through 1996 and multilocus enzyme electrophoresis typing of serogroup B isolates from June 1993 through April 1995 and from April through June 1996.

PATIENTS

A total of 836 persons with invasive meningococcal disease.

MAIN OUTCOME MEASURES

Disease frequency and clonality of strains.

RESULTS

Serogroup B disease incidence rates more than doubled from the preepidemic period in 1987-1992 (1.0 case per 100000 population) to the recent epidemic period in 1995-1996 (2.2 cases per 100000). The age-specific incidence rate of serogroup B disease among those 15 through 19 years old increased 13-fold between the preepidemic period (0.5 case per 100000) and 1995-1996 (6.4 cases per 100000). However, the proportion of cases with meningococcemia and the case-fatality rate did not change. Of 99 Neisseria meningitidis isolates obtained from 1993-1995, 88 (89%) belonged to the ET-5 complex. Of these, 69 (78%) were a single clone, designated 301. Of 20 serogroup B isolates from 1996, 18 (90%) belonged to the ET-5 complex; 17 (94%) were the 301 clone.

CONCLUSION

Serogroup B meningococcal disease incidence continues at high levels in Oregon with increasing predominance of the ET-5 clonal strains.

Lack of association between Borna disease virus infection and neurological disorders among HIV-infected individuals

Viruses have been proposed as etiologic cofactors in the pathogenesis of HIV-related neurological disease. To investigate the etiologic potential of Borna disease virus (BDV) in these disorders, two populations were studied: (1) 27 prospectively identified patients with various neurological disorders were evaluated with BDV RT-PCR (CSF, PBMC), and BDV serology, and (2) a separate group of 25 retrospectively studied patients with AIDS dementia complex was evaluated using BDV serology only. A novel, BDV p40 gene RT-PCR assay was developed: conserved primers were used in a non-nested amplification, detecting less than 100 BDV RNA copies and all of nine wild-type, confirmed animal BDV infections. BDV seroprevalences were 12.5% and 8.0%, respectively, which are similar to the general HIV-infected population. None of the prospectively studied patients had detectable BDV RNA in their CSF or PBMC. Our findings do not support the hypothesis that BDV infections are responsible for HIV-related neurological disorders.