Acquired sensorimotor polyneuropathy in an adolescent boy with primary intracranial sarcoma.

Acquired polyneuropathies (PN) are rare in childhood and adolescent. We report on a 15-year-old male patient who presented with progressive gait instability, ataxia, neuropathic pain, distal muscle weakness and progressive loss of ambulation. Nerve conduction studies (NCS) revealed a progressive demyelinating sensorimotor polyneuropathy predominantly of the lower limbs. Cerebrospinal fluid (CSF) analyses revealed a cytoalbuminologic dissociation. Extensive diagnostic workup for autoantibodies and inflammatory markers was inconclusive. Corticosteroids and intravenous immunoglobulins did not affect. Cranial MRI revealed leptomeningeal enhancement of the cerebellum and the brainstem. Brain biopsy of the cerebellar lesions revealed an unclassifiable sarcoma. The patient was treated according to the CWS guidance study resulting in a decrease in enhanced lesion size. After two years NCS still revealed a demyelinating sensorimotor PN. This case report describes for the first time the clinical course of a chronic PN, putative paraneoplastic, associated with isolated unclassifiable CNS-sarcoma in an adolescent patient. Paraneoplastic pathogenesis should be considered in an unusual sequence of subacute progressive neurological symptoms even in children and adolescents.

Frequency of participation and association with functioning in adolescents born extremely preterm - Findings from a population-based cohort in northern Germany.

BACKGROUND: Outcomes after extremely preterm birth (<28 weeks gestation) have been studied intensely, and follow-up into adulthood is well-established. Following the introduction of the International Classification of Functioning, Disability and Health, participation has been recognized to be a relevant outcome in rehabilitation research. During adolescence, participation is crucial to adapting to new social roles. The aim of our study was to investigate participation in the domains Autonomy, Relationships and Community Recreation. METHODS: Participation was assessed as part of a cross-sectional, population-based study in a German federal state examining all adolescents born between January 1997 and December 1999 at under 27 weeks gestation. Of the surviving 90 adolescents, 72 (80%) were followed-up at age 14 to 17. Frequency of participation was assessed using the short form of the Questionnaire of Young People's Participation and compared to matched peers. Associations with physical, cognitive, and psychological functioning and contextual factors were examined using multivariate regression. RESULTS: Frequency of participation in Autonomy, Relationships, and Community Recreation in adolescents born extremely preterm was significantly lower than that of matched peers from the general population (p < 0,001). Lower frequency of participation in Autonomy and Relationships was associated with severe physical and cognitive impairment, and psychological problems. Fifty-seven percent of the adjusted variance in Autonomy and 31% of the adjusted variance in Relationships was explained by our regression models. CONCLUSION: Further research is warranted to investigate additional factors associated with the restricted frequency of participation of adolescents born preterm to design suitable interventions for improving participation.

Marijuana use in potential liver transplant candidates.

Concern exists that liver transplant center substance abuse policies may have an inappropriate and disproportionate impact on marijuana users. Our hypothesis is that patients with chronic liver disease who were marijuana users will have inferior survival. This is a retrospective (1999-2007) cohort study. The primary outcome measure is time-dependent, adjusted patient survival from the time of liver transplant evaluation. The primary exposure variable is a positive cannabinoid toxicology screen during the liver transplant evaluation period. Overall, 155 patients qualified as marijuana users while 1334 patients were marijuana non-users. Marijuana users were significantly (p < 0.05) younger (48.3 vs. 52.1), more likely to be male (78.1% vs. 63.0%), have hepatitis C (63.9% vs. 40.6%) and were less likely to receive a transplant (21.8% vs. 14.8%). Marijuana users were more likely to use tobacco, narcotics, benzodiazepines, amphetamines, cocaine or barbiturates (p < 0.05). Unadjusted survival rates were similar between cohorts. Upon multivariate analysis, MELD score, hepatitis C and transplantation were significantly associated with survival, while marijuana use was not (HR 1.09, 95% CI 0.78-1.54). We conclude that patients who did and did not use marijuana had similar survival rates. Current substance abuse policies do not seen to systematically expose marijuana users to additional risk of mortality.

Lipopolysaccharide induces memory-processing deficits in day-old chicks.

Recent evidence has demonstrated that immune activation can result in cognitive deficits due to the actions of the proinflammatory cytokines. These series of studies examined the effects of peripheral administration of lipopolysaccharide (LPS) on the memory processes of day-old chicks trained on a single-trial passive-avoidance task. LPS impaired performance in a dose- and time-dependent manner. Maximal impairment was produced by a dose of 2.5-mg/kg LPS administered 60 min prior to training. Retention tests revealed that deficits in memory processing appeared between 10 and 20 min posttraining. These results demonstrate an inhibitory effect of LPS on memory processing at the transition point from short-term memory to intermediate-term memory.

Protein transfer of glycosyl-phosphatidylinositol-B7-1 into tumor cell membranes: a novel approach to tumor immunotherapy.

Modification of tumor cells with one or more costimulatory adhesion molecules has been proposed as a means to develop therapeutic cancer vaccines for use in human immunotherapy. Expression of B7-1 (CD80) in tumors by gene transfer creates an immunogenic tumor cell that induces antitumor immunity and protects mice from further challenge with wild-type tumor cells. In this report, we demonstrate that protein transfer of glycosyl-phosphatidylinositol (GPI)-anchored costimulatory molecules into tumor cell membranes could be used as an alternative to gene transfer for tumor immunotherapy. Incubation of isolated tumor membranes with purified GPI-anchored B7-1 results in stable incorporation of B7-1 on tumor cell membranes within a few hours. Immunization of C57BL/6 mice with EG7 tumor membranes modified to express GPI-B7-1 by protein transfer induces tumor-specific T-cell proliferation and CTLs. In addition, immunization with these EG7 membranes protects mice from parental tumor challenge. The protein transfer approach used here does not require foreign vectors or live tumor cells and is completed within a matter of hours. Irradiated cells or membrane preparations from fresh or frozen tumor tissue can be used. Therefore, protein transfer of glycolipid-anchored molecules provides an efficient and novel approach to modify tumor membranes for human immunotherapy. This approach is not limited to costimulatory molecules because any cell surface protein can be converted to a GPI-anchored form by recombinant techniques.

Detection of a soluble form of B7-1 (CD80) in synovial fluid from patients with arthritis using monoclonal antibodies against distinct epitopes of human B7-1.

The costimulatory molecule B7-1 (CD80) has been shown to be an important component for T cell immune responses. We have generated several monoclonal antibodies (PSRM-1, -2, -3, -6, and -7) against B7-1 using a human glycosylphosphatidylinositol-anchored B7-1 (GPI-B7-1) as an antigen. These monoclonal antibodies are able to detect B7-1 by flow cytometry, ELISA, and Western blotting. One antibody in particular, PSRM-3, blocks the CD28/CTLA-4 interaction with B7-1 and consequently blocks costimulation of T cells. The other PSRM monoclonal antibodies did not compete with PSRM-3 for recognition of B7-1 and also failed to block B7-1 interaction with CTLA-4 and CD28, indicating that these antibodies bind to different epitopes. PSRM-3 and -7 detect phosphatidylinositol-specific phospholipase C-released soluble GPI-B7-1 in a sandwich ELISA. We used this sandwich ELISA to assay for the presence of a soluble form of B7-1 in synovial fluids of arthritis patients. By sandwich ELISA, B7-1 was detected in the synovial fluid of 5/11 patients with rheumatoid arthritis, 5/5 patients with osteoarthritis, and 2/6 patients with other forms, including crystalline-induced arthritis. The presence of soluble B7-1 was confirmed by immunoprecipitation using PSRM-3-coupled Sepharose beads. The source and function of soluble B7-1 are unknown at present; it is possible, however, that the soluble form of B7-1 molecule may play a local immunoregulatory role which may suppress or induce inflammation depending upon whether it interacts with the T cell costimulatory CD28 molecule or the negative signaling CTLA-4 molecule.

The effects of the number and frequency of physical therapy treatments on selected outcomes of treatment in patients with anterior cruciate ligament reconstruction.

Health care reform will quite possibly change the delivery of physical therapy by demanding physical therapists to be more accountable for providing appropriate, yet cost-effective treatment. The purpose of this study was to retrospectively compare the results after anterior cruciate ligament (ACL) reconstruction between two groups of patients with different numbers and frequencies of physical therapy visits postoperatively. Two random samples of 100 patients from a total of 1,345 patients identified as undergoing ACL reconstruction from 1990 through 1993 were included. Group A patients attended physical therapy regularly and participated in a home exercise program, while patients in Group B attended limited physical therapy visits and also performed a prescribed home exercise program. Both groups followed the same postoperative rehabilitation program for early range of motion, early weight bearing, and muscle control. The outcome variables measured 1, 6, and 12 months postoperatively included the number of structured visits to physical therapy, range of motion, isokinetic strength testing, and subjective rating. Group A averaged 20 visits in the first 6 months while Group B averaged seven visits. The results revealed no significant difference for flexion, isokinetic strength, or subjective rating. There was a significant difference for hyperextension (Group A, 2 degrees; Group B, 6 degrees). The results of this investigation indicated that by following a structured physical therapy program postoperatively, it is possible for patients to achieve a successful outcome with a limited number of routine physical therapy visits.

Changes of volume substitution for the treatment of hemorrhage within 10 years and their costs.

Whereas 10 years ago blood loss was substituted by whole blood application together with colloidal or crystalloid substitutes, this behavior changed to a distinct therapy according to the changed laboratory parameters with the application of red cell concentrates together with fresh frozen plasma (FFP). By means of two representative operations (resection of sigma and hemicolectomy) the behavior of volume application and the substitution of blood and blood components were controlled for the years 1980 and compared with the behavior of 1990. In addition to that the costs for both behaviors were calculated and compared. The volume substitution of altogether 176 patients was investigated. 87 patients were operated in the year 1980 and 89 patients in the year 1990. 60% sigma resection were observed on both decades. The analysis revealed that the main substitute (60%) was whole blood in the year 1980 whereas in the year 1990 only 3% of the patients were treated with whole blood. A reverse development was observed with the application of red cell concentrates which was only 2% in the year 1980 but 54% in the year 1990. Unexpectedly the consumption of FFP remained nearly constant in both decades whereas the administration of 5% albumin increased from 40% to 80%. Also the behavior with regard to colloidal substitutes changed markedly within the 2 decades. Dextran and gelatin preparations were exclusively applied in the year 1980 and starch preparations in mainly the year 1990. This changed behavior was responsible for an increase of the costs of 100 $US for every patient. Although the changed behavior can be explained with advantages for the patient but this must be paid by an increase of the costs.

A novel Tth111I restriction fragment length polymorphism (RFLP) allows tracing of X-chromosome inactivation in the (Xid) heterozygote.

The X-linked immunodeficiency (Xid) in CBA/N mice serves as a model for the X-linked agammaglobulinemia (XLA) syndrome in man. X-chromosome inactivation in F1 heterozygotes derived from CBA/N (Xxid/Xxid) and B6.Pgk-1a (X+/Y) was investigated by monitoring the methylation status of the individual Pgk-1 alleles, Pgk-1b and Pgk-1a, respectively, using a novel Tth111I RFLP. Results indicate that in circulating B lymphocytes of female heterozygotes, only the X chromosomes carrying the normal alleles (X+) are active (nonrandom inactivation of the X chromosome), whereas in non-B cells both the X chromosomes (X+ and Xxid) are active (random inactivation of the X chromosome). These results were further confirmed by direct evaluation of transcription of the Btk gene, the gene mutated both in Xid and in XLA.

Induction of autologous tumor-specific cytotoxic T-lymphocyte activity against a human renal carcinoma cell line by B7-1 (CD8O) costimulation.

Recently mouse models have shown that expression of costimulatory molecules such as B7-1 on tumor cells can induce tumor-specific immunity, suggesting that tumor cells modified to express costimulatory molecules can be a potential tumor vaccine. To investigate the importance of B7-1 co-stimulation in induction of autologous tumor immunity in humans, we established a renal carcinoma cell line, RCC-1, from a tumor resection and studied the patient's antitumor immune responses in vitro. The RCC-1 cell line constitutively expressed major histocompatibility complex (MHC) class I, intercellular adhesion molecule (ICAM)-1, and leukocyte function-associated antigen (LFA)-3 molecules, and MHC class II molecules were induced by interferon-gamma (IFN-gamma) treatment in vitro. However, neither RCC-1- nor IFN-gamma-treated RCC-1 cells expressed B7-1, and both failed to induce T-cell proliferative responses in mixed lymphocyte and tumor cell reaction (MLTR) assays, suggesting that the costimulatory signals provided by cell adhesion molecules such as ICAM-1 and LFA-3 were not sufficient to elicit an antitumor immune response. However, on transfection of the human B7-1 into RCC-1, these cells were able to induce a significant T-cell proliferation in MLTR assays. This T-cell response could be blocked by anti-B7 mAb treatment of the tumor cells. RCC-1B7 cells also induced the generation of tumor-specific cytolytic T lymphocytes to the parent RCC-1 cells in vitro, with little nonspecific cytolysis of an unrelated RCC line, A498, or autologous phytohemagglutinin (PHA) blasts. This specific cytotoxicity could be abrogated by anti-CD8 mAb and complement treatment. In summary, our study indicates that B7-1-CD28 interaction plays a critical role in induction of autologous tumor-specific cytotoxic T lymphocytes (CTLs) in humans, suggesting that the costimulatory molecule transfected tumor cells could be useful in expanding tumor-specific autologous CTL in vitro for adoptive tumor immunotherapy.

Phase III randomized trial of interleukin-2 with or without lymphokine-activated killer cells in the treatment of patients with advanced renal cell carcinoma.

BACKGROUND: Treatment with interleukin-2 (IL-2) and lymphokine-activated killer cells (LAK) resulted in responses in some patients with advanced renal cell carcinoma (RCC). However, the relative therapeutic benefit of the addition of LAK to IL-2 was unknown. METHODS: A randomized Phase III trial was conducted in patients with RCC comparing continuous intravenous infusion (CI) IL-2 alone with CI IL-2 plus LAK. Interleukin-2 was administered at 3 x 10(6) U/m2/day on days 1-5, 13-17, 21-24, and 28-31. Patients on the LAK treatment arm underwent leukapheresis on days 8-10 and LAK cell reinfusion on days 13-15. The results are reported with long-term follow-up. The published experience with IL-2 alone or with the addition of LAK was investigated in a quantitative literature survey. The response proportions were studied by schedule (high dose bolus, moderate dose, low dose) and by concomitant administration of LAK. RESULTS: Seventy-one patients were treated, 36 on the IL-2 arm and 35 on the IL-2 plus LAK arm. Four patients (6%) had major responses (two complete, two partial). The median survival of all patients was 13 months (95% confidence interval [CI], 9-18 months). There were no differences between treatment arms with regard to response (P = 0.61) and survival (P = 0.67). More patients on the LAK arm experienced pulmonary toxicity (P = 0.008). The overall weighted response proportion was 16% (95% CI, 8%-24%) for the 39 published series of 1291 patients treated with IL-2. The 95% confidence intervals for response proportion overlapped when compared by schedule and by administration of LAK. CONCLUSIONS: The dose and schedule of IL-2 used in this study resulted in a low level of antitumor activity and the addition of LAK did not improve the response rate against RCC. Given the infrequent, but reproducible, responses with IL-2 and interferon-based regimens, continued investigation of these agents is warranted as is the study of new cytokines. Alternative treatment strategies should be studied in RCC and new agents and treatment regimens that appear promising in Phase II studies must be studied in randomized trials.

Construction, purification, and functional incorporation on tumor cells of glycolipid-anchored human B7-1 (CD80).

To generate a potent cell-mediated immune response, at least two signals are required by T cells. One is engagement of the T-cell receptor with peptide-bearing major histocompatibility complex molecules. The other signal can be delivered by various molecules on the antigen-presenting cell, such as B7-1 (CD80). Many tumor cells escape immune recognition by failing to express these costimulatory molecules. Transfection of the B7 gene into some murine tumor cells allows for immune recognition and subsequent rejection of the parental tumor. We have studied an alternative approach for the introduction of B7-1 onto the surface of tumor cells. This method involves purified glycosyl-phosphatidylinositol (GPI)-anchored proteins which can spontaneously incorporate their lipid tail into cell membranes. We have created and purified a GPI-anchored B7-1 molecule (called GPI-B7) which is able to bind its cognate ligand, CD28, and incorporate itself into tumor cell membranes after a short incubation. Tumor cells that have been reconstituted with GPI-B7 can provide the costimulatory signal needed to stimulate T cells. These findings suggest an approach for the introduction of new proteins onto cell membranes to create an effective tumor vaccine for potential use in human immunotherapy.

Frequency of hypoxanthine guanine phosphoribosyltransferase (HPRT-) T cells in the peripheral blood of cardiac transplant recipients. A noninvasive technique for the diagnosis of allograft rejection.

BACKGROUND: Histological evaluation of serial endomyocardial biopsies performed at fixed time intervals after cardiac transplantation is the universal method used for the detection of cardiac rejection and assessment of the adequacy of antirejection therapy. No noninvasive methodology thus far investigated has achieved a high enough sensitivity and predictive accuracy to be considered as a potential replacement for endomyocardial biopsy in the detection of rejection in adults. The present study exploited the finding that the rate of spontaneous mutation in the hypoxanthine guanine phosphoribosyltransferase (HPRT) gene is higher in proliferating human T cells than in resting cells. Thus, it was reasoned that in the posttransplantation setting, the frequency of HPRT- cells in peripheral blood may provide an indirect measure of alloactivated T lymphocytes. METHODS AND RESULTS: This study consisted of determining the clonal frequency of HPRT- mutant cells (FMC/10(6) peripheral blood mononuclear cells [PBMCs]) within a total of 293 peripheral blood samples representing various numbers of sequential samples from each of 27 transplant recipients. These sequential samples represented time periods when endomyocardial biopsy specimens showed either (1) no evidence of rejection (n = 5 patients), (2) a single initial episode after transplantation of early (< 1 year) or late (> 1 year) rejection (n = 12 patients), or (3) multiple rejection episodes (n = 10 patients). Statistical analyses were used to quantify the time profiles of FMC/10(6) PBMCs in serial samples among transplant recipients and to determine the association of these profiles with both the onset of first rejection episodes and, in appropriate patients, the recurrence of rejection episodes. Data showed that PBMCs from patients with no evidence of rejection uniformly gave low values of < 6 FMC/10(6) cells, a frequency similar to that seen in healthy nontransplanted volunteers. In contrast, 19 of the 22 PBMC samples that were obtained from patients whose corresponding biopsy sample was diagnosed with a histological rejection grade of > or = 3 gave values of > 6 FMC/10(6) cells, 11 of which gave values > 50/10(6) cells (range, 146 to 46,982 FMC/10(6) cells). A significant association between the onset of first rejection and an increased rate of FMC/10(6) values was noted (P = .0001). The ability of a rising trend in FMC/10(6) values to correctly identify the onset of rejection was 81.8% and to correctly identify no rejection, 100%. In addition, a significant association between recurrent rejection episodes and persistence of high FMC/10(6) values in the weeks after treated rejection episodes was noted (P = .0003). The ability of a persistently elevated trend in values of FMC/10(6) cells to correctly identify recurrent rejection was 90% and to correctly identify no rejection, 100%. CONCLUSIONS: Increasing frequencies of HPRT- mutant cells in peripheral blood correlated with the onset of first rejection, and persistently elevated HPRT- mutant cells in the weeks after a treated rejection episode correlated with recurrent rejection. This quantitative noninvasive assay may thus serve as a useful adjunct to endomyocardial biopsy for monitoring post-cardiac transplantation patients, and its use as a prospective diagnostic tool merits further study.

Purification and optimization of functional reconstitution on the surface of leukemic cell lines of GPI-anchored Fc gamma receptor III.

Purified glycosyl phosphatidyl inositol (GPI)-anchored cell surface proteins can be reincorporated spontaneously into the cell membrane by incubating the cells with these proteins. This unique property provides a novel way of introducing cell surface receptors on live cell membranes without the use of gene transfection. Since any classical transmembrane cell surface protein can be converted to a GPI anchored protein by recombinant techniques, this method provides a means of studying ectodomain associated receptor functions on various cell types. Moreover, in some circumstances, it can be used to correct deficient cellular functions resulting from lack of cell surface protein expression. Using GPI-anchored Fc gamma receptor III (CD16B), a low affinity Fc gamma receptor, we have systematically studied the optimal conditions for reconstitution of a functional receptor on nucleated cells. CD16B is purified to homogeneity from neutrophil lysates by single step immunoaffinity chromatography. The purified CD16B is functionally active as evidenced by its ability to bind IgG opsonized erythrocytes. CD16B incorporation on nucleated cells is temperature dependent with an optimum of 37 degrees C. The level of expression of incorporated CD16B is also depend on the concentration of CD16B available and the duration of incubation. The incorporated CD16B retains its ability to bind ligand and also mediates endocytosis of the bound ligand. In summary, our results demonstrate that purified, functionally active GPI-anchored receptors can be expressed on desired cells in a controlled manner and retain some functional properties.

Expression of heat-stable antigen on tumor cells provides co-stimulation for tumor-specific T cell proliferation and cytotoxicity in mice.

Heat-stable antigen (HSA/J11d/possibly homologous to CD24), a cell adhesion molecule capable of providing a co-stimulatory signal for T cell proliferation, is expressed on B cells, activated T cells, monocytes, granulocytes, Langerhans cells and thymocytes. Recent studies have demonstrated that co-stimulatory signals provided by cell adhesion molecules such as B7-1 play an essential role in generation of an anti-tumor immune response. To examine whether the co-stimulatory signal provided by HSA can induce an anti-tumor immune response, we have transfected HSA cDNA into the murine melanoma cell line K1735M2, and examined the ability of this transfected cell line to induce tumor-specific T cell responses. The results demonstrate that spleen cells from mice immunized with HSA-transfected K1735M2 cells showed enhanced T cell proliferation in a mixed lymphocyte tumor reaction (MLTR) assay and also demonstrated a significant anti-tumor cytotoxicity to the parent tumor cell (K1735M2). This anti-tumor cytolytic activity could be abrogated by pretreatment of effector cells with anti-mouse CD8 monoclonal antibody and complement. Under similar conditions, spleen cells from C3H mice immunized with vector-transfected K1735M2 cells neither actively proliferate in an MLTR assay, nor did they exert significant cytolytic activity against the respective tumor cells. In summary, our study demonstrated that HSA can provide a co-stimulatory signal for the T cell immune response against tumor cells in a murine model.

Absence of CSF-1 in macrophage-deficient op/op mice has differential effects on macrophage colony stimulating activity (M-CSA) released by various organs and cells.

The absence of detectable levels of CSF-1 in op/op mice results in a marked deficiency of macrophage colony-stimulating activity (M-CSA) in both the unstimulated and postendotoxin sera of these animals. These deficiences are not secondary to the presence of an inhibitor of macrophage formation. In contrast, various organs, particularly the organs of endotoxin-treated op/op mice, released amounts of M-CSA comparable to those of normal mice. Similarly, mitogen-stimulated lymphoid cells from op/op mice released either similar or increased amounts of M-CSA compared to mitogen stimulated +/+ lymphoid cells. On the other hand, conditioned media from cultures of fibroblastoid cells obtained from primary and secondary cultures of op/op organs were nearly totally devoid of M-CSA. However, incubation of these op/op fibroblasts with endotoxin in vitro induced the easily and readily detectable levels of M-CSA. These data suggest that CSF-1 is most likely a major source of M-CSA in serum and postendotoxin serum, while its contribution to soluble M-CSA in other organs may be only partial. In addition, in specific circumstances, the induced release of other macrophage growth factors may partially compensate for CSF-1 deficiency. Furthermore, it appears that the generalized macrophage deficiency in op/op mice cannot be fully explained by the deficiency of soluble M-CSA (soluble CSF-1) and argues for an in vivo role of membrane-bound CSF-1. These data may be interpreted as supporting a model in which the regulation of CSF-1-dependent and CSF-1-independent macrophage production is carried out by partly unrelated mechanisms.

Evidence for simian immunodeficiency virus-specific IgM and IgG response in peripheral blood mononuclear cells of serum enzyme-linked immunosorbent assay-negative nonhuman primates.

In vitro polyclonal activation of peripheral blood mononuclear cells (PBMCs) from 70% of the simian immunodeficiency virus (SIV) serum enzyme-linked, immunosorbent assay (ELISA)-negative sooty mangabeys leads to synthesis and release of low but significant and reproducible levels of SIV-reactive antibodies, as determined by ELISA and Western blot analysis. The predominant isotype of SIV-reactive antibodies in the pokeweed mitogen (PWM) supernatant fluids from serum ELISA-negative mangabeys is IgM, whereas the predominant isotype of SIV-reactive antibodies in seropositive mangabeys is IgG. Depletion of CD8+ cells led to a marked increase in the levels of SIV-reactive antibodies detected in supernatant fluids from PWM-induced cultures from the serum ELISA-negative mangabeys. No evidence for such SIV-reactive antibodies has been found, to date, in similar unfractionated or CD8+ T-cell-depleted PWM-induced PBMC cultures from uninfected macaques. Supernatant fluids from PWM cultures of PBMCs from a select group of serum ELISA-negative mangabeys, when concentrated five times, were shown to give a Western blot profile against SIV, similar to the profile seen with plasma from seropositive infected macaques and mangabeys. Evidence is presented to show that these serum ELISA-negative mangabeys are most likely latently infected with SIV. This evidence, which was obtained in samples from such ELISA-negative mangabeys, includes the detection of reverse transcriptase activity and the presence of SIV p27 in supernatant fluids of phytohemagglutinin-stimulated PBMCs in vitro. In addition, the data show the presence of CD8+ T cells that regulate SIV-specific Ig synthesis and show the detection of gag sequences by the polymerase chain reaction. Thus, the PWM assay described herein may provide a valuable additional tool for detection of lentivirus infection before or in the absence of seroconversion.

Two measurement techniques for assessing subtalar joint position: a reliability study.

Proper assessment of the subtalar joint is critical for foot and ankle evaluation. Yet, reliability of open kinetic chain goniometric measurements of the subtalar joint has been poor. Two alternative techniques, navicular height and calcaneal position with an inclinometer, have been reported in the literature but lack reliability assessment. The purpose of this study was to determine the intertester and intratester reliability of navicular height and calcaneal position using an inclinometer. Thirty healthy, volunteer subjects (22 females, age 24 +/- 3.6 years; eight males, age 25 +/- 5.1 years) participated in this study. Two testers performed repeated measures on both feet of each subject (N = 60) during two testing sessions. Testers determined the 1) subtalar neutral position, 2) resting position, and 3) difference between these two measurements using an inclinometer for calcaneal position and navicular height. Intratester and intertester reliabilities (ICC 2, 1), standard errors of measurement, and 95% confidence intervals were determined. Intertester and intratester reliability for calcaneal position ranged from .68 to .91 for all measurements. Intertester and intratester reliability for navicular height ranged from .73 to .96 for all measurements. We conclude that these weight-bearing measurement techniques are reliable and acceptable for clinical and research purposes as measured. In addition, we hypothesize that these measurement techniques are simpler than previously described open kinetic chain methods.