Propofol-induced myoclonus during maintenance of anaesthesia

Myoclonus is a known side effect of propofol and can interfere with surgery and possibly precipitate patient injury. Here, we report a 23-year-old patient undergoing an L5 osteoblastoma resection with a predominantly propofol-based anaesthetic who developed intra-operative myoclonus. Other adjuncts included ketamine, lidocaine and fentanyl infusions. The myoclonus did not improve after deepening the anaesthetic with propofol, opioid boluses or discontinuation of the lidocaine infusion. The myoclonus ceased after reducing the propofol infusion and increasing the ketamine and opioid infusions. The remainder of the intra-operative course was uneventful. This report details our intra-operative management of propofol-induced cortical reflex myoclonus and discusses our institution's experience with treating this phenomenon.

A Once Malignant Malady: the Story of Schizophrenia and the Path to Prevention

Schizophrenia is synonymous in the public’s mind with madness. To see someone experiencing a florid psychosis, who has lost the ability to distinguish between the real and the imagined, is to know that you are in the presence of insanity. Schizophrenia has existed for centuries. It’s one of the leading causes of disability in the world, with a lifetime prevalence of about 1 percent of the population. That’s 3.3 million people in the US and 78 million worldwide. Schizophrenia afflicts rich and poor, genders, all races and ethnic groups. Schizophrenia has been subject to many misconceptions, from spiritual affliction to social deviance, psychodynamic conflicts to romanticized notions of iconoclastic creativity. Perhaps, the most significant myth about the disease is that there are no effective treatments or cure. But the reality couldn’t be more different: today’s treatments are effective and often lifesaving. Beginning in the mid-twentieth century, scientific progress has enhanced our understanding of schizophrenia as a brain disorder that disrupts thought, perception, and emotion. Findings of abnormalities in brain structure, biochemical analytes and genetic mutations have revealed its causal mechanisms and have guided the search for effective pharmacologic and psychosocial treatments. This presentation traces the evolution of our social and scientific understanding of Schizophrenia. It will elucidate how science and medicine dispelled the superstition and myth surrounding this ancient malady of the mind and forged a path toward its understanding as a brain disorders and offers affected people, not just humane treatment, but the promise of its ultimate prevention.

Disclosure

No significant relationships.

miR-200 promotes the mesenchymal to epithelial transition by suppressing multiple members of the Zeb2 and Snail1 transcriptional repressor complexes

The miR-200 family promotes the epithelial state by suppressing the Zeb1/Zeb2 epithelial gene transcriptional repressors. To identify other miR-200-regulated genes, we isolated mRNAs bound to transfected biotinylated miR-200c in mouse breast cancer cells. In all, 520 mRNAs were significantly enriched in miR-200c binding at least twofold. Putative miR-200-regulated genes included Zeb2, enriched 3.5-fold in the pull down. However, Zeb2 knockdown does not fully recapitulate miR-200c overexpression, suggesting that regulating other miR-200 targets contributes to miR-200's enhancement of epithelial gene expression. Candidate genes were highly enriched for miR-200c seed pairing in their 3'UTR and coding sequence and for genes that were downregulated by miR-200c overexpression. Epidermal growth factor receptor and downstream MAPK signaling pathways were the most enriched pathways. Genes whose products mediate transforming growth factor (TGF)-β signaling were also significantly overrepresented, and miR-200 counteracted the suppressive effects of TGF-β and bone morphogenic protein 2 (BMP-2) on epithelial gene expression. miR-200c regulated the 3'UTRs of 12 of 14 putative miR-200c-binding mRNAs tested. The extent of mRNA binding to miR-200c strongly correlated with gene suppression. Twelve targets of miR-200c (Crtap, Fhod1, Smad2, Map3k1, Tob1, Ywhag/14-3-3γ, Ywhab/14-3-3β, Smad5, Zfp36, Xbp1, Mapk12, Snail1) were experimentally validated by identifying their 3'UTR miR-200 recognition elements. Smad2 and Smad5 form a complex with Zeb2 and Ywhab/14-3-3β and Ywhag/14-3-3γ form a complex with Snail1. These complexes that repress transcription assemble on epithelial gene promoters. miR-200 overexpression induced RNA polymerase II localization and reduced Zeb2 and Snail1 binding to epithelial gene promoters. Expression of miR-200-resistant Smad5 modestly, but significantly, reduced epithelial gene induction by miR-200. miR-200 expression and Zeb2 knockdown are known to inhibit cell invasion in in vitro assays. Knockdown of each of three novel miR-200 target genes identified here, Smad5, Ywhag and Crtap, also profoundly suppressed cell invasion. Thus, miR-200 suppresses TGF-β/BMP signaling, promotes epithelial gene expression and suppresses cell invasion by regulating a network of genes.

In silico prediction of Ara h 2 T cell epitopes in peanut-allergic children

BACKGROUND

Despite the frequency and severity of peanut allergy, the only approved treatment is strict avoidance. Different types of immunotherapy with crude peanut extract are not universally effective and have been associated with relatively high adverse reaction rates.

OBJECTIVE

We sought to determine whether in silico predictive algorithms were useful in identifying candidate peptides for an Ara h 2 peptide-based vaccine using peanut-allergic patients' peripheral blood mononuclear cells (PBMCs) in vitro. A human leucocyte antigen (HLA) distribution analysis was also performed.

METHODS

Major histocompatibility complex (MHC)-class II-binding peptides were predicted using NetMHCIIpan-2.0 and NetMHCII-2.2 algorithms. PBMCs from 80 peanut-allergic patients were stimulated with overlapping 20-mer Ara h 2 peptides. Cell supernatant cytokine profiles were evaluated by multiplex assays. HLA-DRB1* and HLA-DQB1* typing were performed.

RESULTS

Four regions of overlapping sequences induced PBMC proliferation and predominant Th2 cytokine production. HLA genotyping showed 30 different DRB1* allele specificities and eight DQ serological specificities. The in silico analysis revealed similar relevant regions and predicted identical or similar core 9-mer epitopes to those identified in vitro. If relevant peptides, as determined by either in vitro or in silico analysis (15 peptides and 9 core epitopes respectively), were used in a peptide-based vaccine, they would cover virtually all subjects in the cohort studied.

CONCLUSIONS AND CLINICAL RELEVANCE

Four dominant regions in Ara h 2 have been identified, containing sequences that could serve as potential candidates for peptide-based immunotherapy. MHC-class II-based T cell epitope prediction algorithms for HLA-DR and -DQ loci accurately predicted Ara h 2 T cell epitopes in peanut-allergic subjects, suggesting their potential utility in a peptide-based vaccine design for food allergy.

Use of hyaluronan in the selection of sperm for intracytoplasmic sperm injection (ICSI): significant improvement in clinical outcomes--multicenter, double-blinded and randomized controlled trial

STUDY QUESTION

Does the selection of sperm for ICSI based on their ability to bind to hyaluronan improve the clinical pregnancy rates (CPR) (primary end-point), implantation (IR) and pregnancy loss rates (PLR)?

SUMMARY ANSWER

In couples where ≤65% of sperm bound hyaluronan, the selection of hyaluronan-bound (HB) sperm for ICSI led to a statistically significant reduction in PLR.

WHAT IS KNOWN AND WHAT THIS PAPER ADDS

HB sperm demonstrate enhanced developmental parameters which have been associated with successful fertilization and embryogenesis. Sperm selected for ICSI using a liquid source of hyaluronan achieved an improvement in IR. A pilot study by the primary author demonstrated that the use of HB sperm in ICSI was associated with improved CPR. The current study represents the single largest prospective, multicenter, double-blinded and randomized controlled trial to evaluate the use of hyaluronan in the selection of sperm for ICSI.

DESIGN

Using the hyaluronan binding assay, an HB score was determined for the fresh or initial (I-HB) and processed or final semen specimen (F-HB). Patients were classified as >65% or ≤65% I-HB and stratified accordingly. Patients with I-HB scores ≤65% were randomized into control and HB selection (HYAL) groups whereas patients with I-HB >65% were randomized to non-participatory (NP), control or HYAL groups, in a ratio of 2:1:1. The NP group was included in the >65% study arm to balance the higher prevalence of patients with I-HB scores >65%. In the control group, oocytes received sperm selected via the conventional assessment of motility and morphology. In the HYAL group, HB sperm meeting the same visual criteria were selected for injection. Patient participants and clinical care providers were blinded to group assignment.

PARTICIPANTS AND SETTING

Eight hundred two couples treated with ICSI in 10 private and hospital-based IVF programs were enrolled in this study. Of the 484 patients stratified to the I-HB > 65% arm, 115 participants were randomized to the control group, 122 participants were randomized to the HYAL group and 247 participants were randomized to the NP group. Of the 318 patients stratified to the I-HB ≤ 65% arm, 164 participants were randomized to the control group and 154 participants were randomized to the HYAL group.

MAIN RESULTS AND THE ROLE OF CHANCE

HYAL patients with an F-HB score ≤65% demonstrated an IR of 37.4% compared with 30.7% for control [n = 63, 58, P > 0.05, (95% CI of the difference −7.7 to 21.3)]. In addition, the CPR associated with patients randomized to the HYAL group was 50.8% when compared with 37.9% for those randomized to the control group (n = 63, 58, P > 0.05). The 12.9% difference was associated with a risk ratio (RR) of 1.340 (RR 95% CI 0.89–2.0). HYAL patients with I-HB and F-HB scores ≤65% revealed a statistically significant reduction in their PLR (I-HB: 3.3 versus 15.1%, n = 73, 60, P = 0.021, RR of 0.22 (RR 95% CI 0.05–0.96) (F-HB: 0.0%, 18.5%, n = 27, 32, P = 0.016, RR not applicable due to 0.0% value) over control patients. The study was originally planned to have 200 participants per arm providing 86.1% power to detect an increase in CPR from 35 to 50% at α = 0.05 but was stopped early for financial reasons. As a pilot study had demonstrated that sperm preparation protocols may increase the HB score, the design of the current study incorporated a priori collection and analysis of the data by both the I-HB and the F-HB scores. Analysis by both the I-HB and F-HB score acknowledged the potential impact of sperm preparation protocols.

BIAS, CONFOUNDING AND OTHER REASONS FOR CAUTION

Selection bias was controlled by randomization. Geographic and seasonal bias was controlled by recruiting from 10 geographically unique sites and by sampling over a 2-year period. The potential for population effect was controlled by adjusting for higher prevalence rates of >65% I-HB that naturally occur by adding the NP arm and to concurrently recruit >65% and ≤65% I-HB subjects. Monitoring and site audits occurred regularly to ensure standardization of data collection, adherence to the study protocol and subject recruitment. Subgroup analysis based on the F-HB score was envisaged in the study design.

GENERALIZABILITY TO OTHER POPULATIONS

The study included clinics using different sperm preparation methods, located in different regions of the USA and proceeded in every month of the year. Therefore, the results are widely applicable.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by Biocoat, Inc., Horsham, PA, USA. The statistical analysis plan and subsequent analyses were performed by Sherrine Eid, a biostatistician. The manuscript was prepared by Kathryn C. Worrilow, Ph.D. and the study team members. Biocoat, Inc. was permitted to review the manuscript and suggest changes, but the final decision on content was exclusively retained by the authors. K.C.W is a scientific advisor to Biocoat, Inc. S.E. is a consultant to Biocoat, Inc. D.W. has nothing to disclose. M.P., S.S., J.W., K.I., C.K. and T.E. have nothing to disclose. G.D.B. is a consultant to Cooper Surgical and Unisense. J.L. is on the scientific advisory board of Origio.

TRIAL REGISTRATION NUMBER

NCT00741494.

Genomics, Transcriptomics and Methylomics: Alternative Approaches for the Analysis of Serotonin System and Antipsychotic Response

Serotonin receptors blockade is the major basis for the action of atypical antipsychotic drugs. Genetic factors affecting the density and/or function of serotonergic receptors, transporters and enzymes may therefore affect antipsychotic response. This exploratory study investigates the effect of ten polymorphisms from HTR1A, HTR1D, HTR2A, HTR3A, HTR3B, HTR4, HTR6, SLC6A4, TPH1, TPH2 genes on antipsychotic response in a sample of 289 patients with DSM-diagnosis of schizophrenia. Clinical Response was assessed using Brief Psychiatric Rating Scale (BPRS). Response was determined as 20% reduction improvement of BPRS compared to baseline. Selection of the biological relevant interactions, regardless the phenotype was performed using different statistics strategies regardless the phenotype to investigate epistasis within the serotonin system. the test for relevant interaction selection showed that 5HT4 and 5HT6 can be in epistatic relationship. the single locus analysis of these two receptor polymorphisms showed no significant results and the logistic regression model incorporating both genes, the clinical and demographic variables was not significant. Even this result is not significant, this strategy aimed to investigate the epistatic effect among genes could be useful for finding relevant biological interaction among genetic variants. Furthermore we are currently analyzing the methylation level of HTR2A in responders and non-responders, this epigenetic analysis will be very valuable in adding more information to the classic pharmacogenetic studies.

Genomewide association for schizophrenia in the CATIE study: results of stage 1

Little is known for certain about the genetics of schizophrenia. The advent of genomewide association has been widely anticipated as a promising means to identify reproducible DNA sequence variation associated with this important and debilitating disorder. A total of 738 cases with DSM-IV schizophrenia (all participants in the CATIE study) and 733 group-matched controls were genotyped for 492,900 single-nucleotide polymorphisms (SNPs) using the Affymetrix 500K two-chip genotyping platform plus a custom 164K fill-in chip. Following multiple quality control steps for both subjects and SNPs, logistic regression analyses were used to assess the evidence for association of all SNPs with schizophrenia. We identified a number of promising SNPs for follow-up studies, although no SNP or multimarker combination of SNPs achieved genomewide statistical significance. Although a few signals coincided with genomic regions previously implicated in schizophrenia, chance could not be excluded. These data do not provide evidence for the involvement of any genomic region with schizophrenia detectable with moderate sample size. However, a planned genomewide association study for response phenotypes and inclusion of individual phenotype and genotype data from this study in meta-analyses hold promise for eventual identification of susceptibility and protective variants.

Focal adhesion kinase is required for CXCL12-induced chemotactic and pro-adhesive responses in hematopoietic precursor cells

Hematopoietic stem/progenitor cells (HSC/P) reside in the bone marrow in distinct anatomic locations (niches) to receive growth, survival and differentiation signals. HSC/P localization and migration between niches depend on cell-cell and cell-matrix interactions, which result from the cooperation of cytokines, chemokines and adhesion molecules. The CXCL12-CXCR4 pathway, in particular, is essential for myelopoiesis and B lymphopoiesis but the molecular mechanisms of CXCL12 action remain unclear. We previously noted a strong correlation between prolonged CXCL12-mediated focal adhesion kinase (FAK) phosphorylation and sustained pro-adhesive responses in progenitor B cells, but not in mature B cells. Although FAK has been well studied in adherent fibroblasts, its function in hematopoietic cells is not defined. We used two independent approaches to reduce FAK expression in (human and mouse) progenitor cells. RNA interference (RNAi)-mediated FAK silencing abolished CXCL12-induced responses in human pro-B leukemia, REH cells. FAK-deficient REH cells also demonstrated reduced CXCL12-induced activation of the GTPase Rap1, suggesting the importance of FAK in CXCL12-mediated integrin activation. Moreover, in FAK(flox/flox) hematopoietic precursor cells, Cre-mediated FAK deletion resulted in impaired CXCL12-induced chemotaxis. These studies suggest that FAK may function as a key intermediary in signaling pathways controlling hematopoietic cell lodgment and lineage development.

The silent treatment: siRNAs as small molecule drugs

As soon as RNA interference (RNAi) was found to work in mammalian cells, research quickly focused on harnessing this powerful endogenous and specific mechanism of gene silencing for human therapy. RNAi uses small RNAs, less than 30 nucleotides in length, to suppress expression of genes with complementary sequences. Two strategies can introduce small RNAs into the cytoplasm of cells, where they are active - a drug approach where double-stranded RNAs are administered in complexes designed for intracellular delivery and a gene therapy approach to express precursor RNAs from viral vectors. Phase I clinical studies have already begun to test the therapeutic potential of small RNA drugs that silence disease-related genes by RNAi. This review will discuss progress in developing and testing small RNAi-based drugs and potential obstacles.

The Bcl-2 family pro-apoptotic molecule, BNIP3 regulates activation-induced cell death of effector cytotoxic T lymphocytes

BNIP3 is a recently described pro-apoptotic member of the Bcl-2 family and in BNIP3 cDNA-transfected cell lines, cell death occurs via a caspase-independent pathway with opening of the mitochondrial permeability transition (PT) pore and rapid loss of mitochondrial transmembrane potential (Delta psi m). However, its expression or function in physiologic cell types is not known. Our results using the T-cell receptor transgenic mice P14, specific for lymphocyte choreomeningitis virus (LCMV) glycoprotein, show that in contrast to the other Bcl-2 family pro-apoptotic molecules, BNIP3 is transcriptionally highly up-regulated in effector cytotoxic T lymphocytes (CTL). Because CTL have a propensity to undergo activation-induced cell death (AICD) upon restimulation, we tested for other features associated with BNIP3-induced cell death. AICD of CTL was caspase-independent as determined by measuring caspase activation during target cell killing as well as by lack of inhibition with caspase inhibitors. Moreover, similar to BNIP3-induced cell death, CTL apoptosis was associated with increased production of reactive oxygen species and decreased Delta psi m. Finally, retroviral transduction of BNIP3 antisense RNA diminished AICD in effector CTL. These results suggest that BNIP3 may play an important role in T-cell homeostasis by regulating effector CTL numbers.

Statistical shape analysis of neuroanatomical structures based on medial models

Knowledge about the biological variability of anatomical objects is essential for statistical shape analysis and discrimination between healthy and pathological structures. This paper describes a novel approach that incorporates the variability of an object population into the generation of a characteristic 3D shape model. The proposed shape representation is a coarse-scale sampled medial description derived from a fine-scale spherical harmonics (SPHARM) boundary description. This medial description is composed of a net of medial samples (m-rep) with fixed graph properties. The medial model is computed automatically from a predefined shape space using pruned 3D Voronoi skeletons. A new method determines the stable medial branching topology from the shape space. An intrinsic coordinate system and an implicit correspondence between shapes is defined on the medial manifold. Several studies of biological structures clearly demonstrate that the novel representation has the promise to describe shape changes in a natural and intuitive way. A new medial shape similarity study of group differences between monozygotic and dizygotic twins in lateral ventricle shape demonstrates the meaningful and powerful representation of local and global form.

Granzyme A activates an endoplasmic reticulum-associated caspase-independent nuclease to induce single-stranded DNA nicks

The cytotoxic T lymphocyte protease granzyme A (GzmA) initiates a novel caspase-independent cell death pathway characterized by single-stranded DNA nicking. The previously identified GzmA substrate SET is in a multimeric 270-420-kDa endoplasmic reticulum-associated complex that also contains the tumor suppressor protein pp32. GzmA cleaved the nucleosome assembly protein SET after Lys(176) and disrupted its nucleosome assembly activity. The purified SET complex required only GzmA to reconstitute single-stranded DNA nicking in isolated nuclei. DNA nicking occurred independently of caspase activation. The SET complex contains a 25-kDa Mg(2+)-dependent nuclease that degrades calf thymus DNA and plasmid DNA. Thus, GzmA activates a DNase (GzmA-activated DNase) within the SET complex to produce a novel form of DNA damage during cytotoxic T lymphocyte-mediated death.

Correlates of substance misuse in patients with first-episode schizophrenia and schizoaffective disorder

OBJECTIVE

To identify factors associated with substance misuse in first-episode patients with schizophrenia or schizoaffective disorder.

METHOD

Twenty-seven patients with a past or current history of substance misuse were compared with 91 patients with no history of misuse on demographic and psychopathological measures before being treated for their first episode of psychosis, and on cognitive measures after 6 months of treatment.

RESULTS

There were no statistically significant differences between groups for sex, schizophrenia subtype, marital status, education, family history of schizophrenia, course of illness, age of onset, baseline symptoms, time to treatment response, medication side effects, attention span, memory and executive functioning. However, dual diagnosis patients were found to have a higher parental social class, better premorbid cognitive functioning, higher IQ and better language skills.

CONCLUSION

First-episode patients with a history of substance misuse have higher intellectual functioning, which may be associated with higher premorbid socioeconomic status and cognitive functioning.

Effector differentiation is not prerequisite for generation of memory cytotoxic T lymphocytes

The lineage relationship between short-lived effector T cells and long-lived memory cells is not fully understood. We have described T-GFP mice previously, in which naive and early activated T cells express GFP uniformly, whereas cells that have differentiated into effector cytotoxic T cells selectively lose GFP expression. Here we studied antigen-specific CD8 T cell differentiation using T-GFP mice crossed to the TCR transgenic (Tg) mice P14 (specific for the lymphocytic choriomeningitis virus glycoprotein peptide, gp33-41). After activation with antigenic peptide, P14XT-GFP CD8(+) T cells cultured in high-dose IL-2 developed into cells with effector phenotype and function: they were blastoid, lost GFP expression, expressed high levels of activation and effector markers, and were capable of immediate cytotoxic function. In contrast, cells cultured in IL-15 or low-dose IL-2 never developed into full-fledged effector cells. Rather, they resembled memory cells: they were smaller, were GFP(+), did not express effector markers, and were incapable of immediate cytotoxicity. However, they mediated rapid-recall responses in vitro. After adoptive transfer, they survived in vivo for at least 10 weeks and mounted a secondary immune response after antigen rechallenge that was as potent as endogenously generated memory cells. In addition to providing a simple means to generate memory cells in virtually unlimited numbers, our results suggest that effector differentiation is not a prerequisite for memory cell generation.

Dressed to kill? A review of why antiviral CD8 T lymphocytes fail to prevent progressive immunodeficiency in HIV-1 infection

CD8 T cells play an important role in protection and control of HIV-1 by direct cytolysis of infected cells and by suppression of viral replication by secreted factors. However, although HIV-1-infected individuals have a high frequency of HIV-1-specific CD8 T cells, viral reservoirs persist and progressive immunodeficiency generally ensues in the absence of continuous potent antiviral drugs. Freshly isolated HIV-specific CD8 T cells are often unable to lyse HIV-1-infected cells. Maturation into competent cytotoxic T lymphocytes may be blocked during the initial encounter with antigen because of defects in antigen presentation by interdigitating dendritic cells or HIV-infected macrophages. The molecular basis for impaired function is multifactorial, due to incomplete T-cell signaling and activation (in part related to CD3zeta and CD28 down-modulation), reduced perforin expression, and inefficient trafficking of HIV-specific CD8 T cells to lymphoid sites of infection. CD8 T-cell dysfunction can partially be corrected in vitro with short-term exposure to interleukin 2, suggesting that impaired HIV-specific CD4 T helper function may play a significant causal or exacerbating role. Functional defects are qualitatively different and more severe with advanced disease, when interferon gamma production also becomes compromised.

Olanzapine for schizophrenia refractory to typical and atypical antipsychotics: an open-label, prospective trial

The role of olanzapine in treatment-resistant schizophrenia is still unresolved. This article presents an open-label, prospective, 14-week trial with olanzapine in patients with schizophrenia and schizoaffective disorder selected for unambiguous resistance to either clozapine or risperidone and to typical antipsychotics. Forty-three inpatients (mean age, 41.6 years; mean duration of illness, 21.7 years) were enrolled and treated after cross-titration from their previous antipsychotic treatment with olanzapine 10 to 40 mg daily without any concomitant antipsychotic medication. Patients were evaluated with the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions Scale, and the Extrapyramidal Symptom Rating Scale. The change with olanzapine treatment was associated with a PANSS total score improvement of 3.7 (SD = 15.6; not significant). There was a significant improvement for the PANSS cognitive and depression/anxiety factors, whereas the PANSS excitement factor worsened. The improvement rate was superior in patients receiving olanzapine doses higher than 20 mg. A total of 16.7% of patients reached response criteria set forth by a previous study. There was a significant decrease in extrapyramidal side effects (t = 2.04; p < 0.05) and statistically significant, yet modest, weight gain. These results indicate that olanzapine is only modestly effective in these severely treatment-resistant patients with schizophrenia. However, a trial with olanzapine can be recommended in these patients before moving to augmentation strategies, given the lack of proven alternatives and the observation that 16.7% of patients reached the response criteria.

CD8 T cells specific for human immunodeficiency virus, Epstein-Barr virus, and cytomegalovirus lack molecules for homing to lymphoid sites of infection

CD8 T cells are classified as naïve, effector, or memory cells on the basis of CD45RA, CD62L, and CCR7 expression. Sequential engagement of cell-surface CD62L and CCR7 receptors is required for efficient trafficking to lymphoid tissue by means of high endothelial venules. Naïve CD8 T cells are CCR7(+)CD62L(+) CD45RA(+), whereas long-term memory cells are CCR7(+)CD62L(+)CD45RA(-). Effector cytotoxic T cells are thought to be CCR7(-)CD45RA(+). The distribution of CD8 subsets and cytolytic protein expression in healthy donors and donors seropositive for human immunodeficiency virus (HIV) were compared. In HIV-infected subjects, CCR7(-) CD8 T cells expanded at the expense of naïve and long-term memory cells. In both healthy donors and HIV-infected donors, CCR7(+) CD8 T cells were uniformly negative for perforin. In all subsets, perforin and granzyme A were not coordinately expressed, with perforin expression being more tightly regulated. The properties of CD8 T cells specific for cytomegalovirus, Epstein-Barr virus (EBV), and HIV were studied by staining with major histocompatibility complex peptide tetramers. Antigen-specific cells for chronic infections with these viruses were uniformly CCR7(-) and predominantly CD62L(-). In 2 HIV-seropositive donors, 3- to 4-fold fewer EBV-tetramer-positive cells were present in lymph nodes compared with blood. Antigen-specific CD8 T cells are therefore preferentially excluded from lymphoid sites, even when infection is primarily in lymphoid tissue. This may protect lymphoid tissues from immunopathological changes but compromise immune defense against viruses, such as HIV and EBV, that target lymphocytes. HIV-specific CD8 T cells do not express CD45RA, whereas EBV- and CMV-specific CD8 T cells are heterogeneous in CD45RA(+) expression. Lack of CD45RA expression may indicate incomplete differentiation of HIV-specific CD8 T cells to cytotoxic T cells.

Lack of utility of intestinal fatty acid binding protein levels in predicting intestinal allograft rejection

INTRODUCTION

The enterocyte-specific protein, intestinal fatty acid binding protein (I-FABP), is detectable in serum only after intestinal injury. Previous studies in animals suggest that I-FABP might be a useful marker of intestinal allograft rejection.

MATERIALS AND METHODS

I-FABP was repetitively measured in nine intestinal transplant recipients and correlated with findings of surveillance endoscopy.

RESULTS

Average interval between I-FABP determination and biopsy was 3.4 days (SD=4.2 days). Average number of rejection episodes per patient totalled 1.6+/-1.2. General linear modeling demonstrated no tendency for increases in serum FABP to precede histologic graft rejection (P=0.263). Restriction of the analysis to I-FABP determinations 1 day before or on the day of biopsy failed to affect these results. Minor increases in I-FABP were often associated with histologically normal grafts, whereas rejection often occurred when I-FABP was not detectable.

DISCUSSION

Serum I-FABP levels do not predict clinical intestinal allograft rejection.

Usefulness of blood culture for hospitalized patients who are receiving antibiotic therapy

We conducted a retrospective study to determine the yield of blood samples drawn for culture during the initial 72 h of antibiotic therapy given to 139 patients who were admitted to the hospital for community-acquired infections or fever. The yield of these blood cultures was predictable and rarely (in only 1 patient [0.72%]) isolated new pathogens.

Granzymes A and B directly cleave lamins and disrupt the nuclear lamina during granule-mediated cytolysis

Cytotoxic T lymphocytes (CTL) induce apoptosis by engaging death receptors or by exocytosis of cytolytic granules containing granzyme (Gzm) proteases and perforin. The lamins, which maintain the structural integrity of the nuclear envelope, are cleaved by caspases during caspase-mediated apoptosis. Although death receptor engagement and GzmB activate caspases, CTL also induce apoptosis during caspase blockade. Both GzmA and GzmB directly and efficiently cleave laminB in vitro, in situ in isolated nuclei and in cells loaded with perforin and Gzms, even in the presence of caspase inhibitors. LaminB is cleaved by GzmA at concentrations of 3 nM, but GzmB is 50 times less active. GzmA cuts laminB at R392; GzmB cuts at the caspase VEVD231 site. Characteristic laminB fragments generated by Gzm proteolysis also are observed during CTL lysis, even in the presence of caspase inhibitors or in cells overexpressing bcl-2. Lamins A/C are direct substrates of GzmA, but not GzmB. GzmA and GzmB therefore directly target critical caspase substrates in caspase-resistant cells.

Effectiveness of second-generation antipsychotics in patients with treatment-resistant schizophrenia: a review and meta-analysis of randomized trials

OBJECTIVE

The authors conducted a review and meta-analysis of studies that compared the efficacy and tolerability of typical and second-generation antipsychotics for patients with treatment-resistant schizophrenia.

METHOD

A systematic search revealed 12 controlled studies (involving 1,916 independent patients), which were included in the review. For the seven studies that compared clozapine to a typical antipsychotic, a meta-analysis was performed to examine clozapine's effects on overall psychopathology, response rate, extrapyramidal symptoms, and tardive dyskinesia.

RESULTS

The meta-analysis confirmed that treatment-resistant schizophrenic patients have more favorable outcomes when treated with clozapine rather than a typical antipsychotic, as reflected by Brief Psychiatric Rating Scale total score, categorical response rate, Scale for the Assessment of Negative Symptoms score, Simpson-Angus Rating Scale score, and compliance rate. Clozapine also conferred benefits on the sickest treatment-resistant schizophrenic patients. Patients treated with olanzapine also had more favorable outcomes with regard to categorical response and compliance rates.

CONCLUSIONS

In the aggregate, the results of a meta-analysis indicated that clozapine exhibits superiority over typical antipsychotics in terms of both efficacy (as measured by improvement in overall psychopathology) and safety (in terms of reduced extrapyramidal side effects). However, the magnitude of the clozapine treatment effect was not consistently robust. Efficacy data for other second-generation antipsychotics in the treatment of patients with refractory schizophrenia were inconclusive. There is, therefore, a growing need to consider new and different treatment strategies, whether they be adjunctive or monotherapeutic, for schizophrenia that continues to be resistant or only partially responsive to treatment.

Longitudinal study of brain morphology in first episode schizophrenia

BACKGROUND

Beginning with Kraepelin, schizophrenia has been viewed as a progressive disorder. Although numerous studies of the longitudinal course of schizophrenia have demonstrated the clinical deterioration that occurs predominantly in the early stages of the illness, the pathophysiology of this clinical phenomenon has not been established. This aspect of the illness may be of critical importance to understanding the pathogenesis of schizophrenia and determining preventive therapeutic strategies. Abnormalities in brain morphology have been consistently described in schizophrenia, but it is not known when in the natural history of the illness they arise and whether they are progressive. Previous studies of brain morphology have been inconclusive, in part because of the variability of methods for image acquisition and analysis, assessment of patients already at chronic stages of their illness with extensive prior treatment exposure, and inadequate periods of follow-up.

METHODS

To address these questions we examined 107 patients in their first episode of schizophrenia or schizoaffective disorder and 20 healthy volunteers using high resolution magnetic resonance imaging (MRI) and clinical assessments of psychopathology and treatment outcome for periods of up to 6 years. Fifty-one patients and 13 control subjects had MRIs after at least 12 months of follow-up.

RESULTS

Results confirm the findings of ventricular enlargement and anterior hippocampal volume reductions in first episode schizophrenia patients that have been previously reported. In addition, we found changes in selected structures over time in relation to treatment outcome, including increases in ventricular volume that were associated with poor outcome patients. Contrary to our hypothesis, there were no significant reductions in cortical and hippocampal volumes over time.

CONCLUSIONS

The finding of progressive ventricular enlargement in patients with poor outcome schizophrenia is consistent with the hypothesis that persistent positive and negative symptoms result in progressive brain changes in the form of ventricular enlargement, possibly due to neurodegeneration rather than the confounding effects of treatment. Future studies of first episodes of schizophrenia should utilize higher resolution imaging techniques that compare clinically well characterized patients with and without poor outcome and recurrent symptoms to control subjects who are well matched to patients for age and gender. There is also a need to control for treatment effects of typical antipsychotic medication on brain structure.

Induction of rapid histone degradation by the cytotoxic T lymphocyte protease Granzyme A

The cytotoxic T lymphocyte protease granzyme A induces caspase-independent cell death in which DNA single-strand nicking is observed instead of oligonucleosomal fragmentation. Granzyme A is a specific tryptase that concentrates in the nucleus of targeted cells and synergistically enhances DNA fragmentation induced by the caspase activator granzyme B. Here we show that granzyme A treatment of isolated nuclei enhances DNA accessibility to exogenous endonucleases. In vitro and after cell loading with perforin, GrnA completely degrades histone H1 and cleaves core histones into approximately 16-kDa fragments. Histone digestion provides a mechanism for unfolding compacted chromatin and facilitating endogenous DNase access to DNA during T cell and natural killer cell granule-mediated apoptosis.

Augmentation therapy reduces frequency of lung infections in antitrypsin deficiency: a new hypothesis with supporting data

STUDY OBJECTIVES

To propose an hypothesis that antiprotease augmentation therapy reduces the incidence of lung infections in alpha(1)-antitrypsin (AAT)-deficient patients, and to present supporting data.

DESIGN

The proposed concept is based on a survey taken via the Internet of patients receiving augmentation therapy for 1 to 10 years compared to similar patients not receiving such therapy.

SETTING

A questionnaire was submitted to patients with a ZZ phenotype for AAT deficiency to determine whether those receiving antitrypsin augmentation therapy were aware of any personal benefit, and whether the therapy had an effect on the frequency of lung infections.

PATIENTS

Ninety-six adult patients receiving human alpha(1)-proteinase inhibitor (alpha(1)-PI) responded, as did 47 similar patients not receiving augmentation therapy.

RESULTS

Seventy-four of 89 patients who had received alpha(1)-PI infusions for > 1 year believed that they had definitely benefited from such therapy. Fifty-six of the 74 patients claiming a benefit attributed this to a reduction in the number of lung infections since starting therapy with alpha(1)-PI infusions. Before starting alpha(1)-PI, the majority of patients had three to five infections per year, dropping to zero to one infection per year during alpha(1)-PI therapy (p < 0. 001).

CONCLUSIONS

Replacement therapy for AAT deficiency-associated emphysema appears to be associated with a marked reduction in the frequency and severity of lung infections. This association must be evaluated further in future, more rigid, prospective studies of AAT augmentation therapy. Findings support the hypothesis that antiprotease therapy with alpha(1)-PI reduces the incidence of lung infections in addition to slowing the deterioration of lung function and causing a reduction in mortality.

Induction of human immunodeficiency virus (HIV)-specific CD8 T-cell responses by Listeria monocytogenes and a hyperattenuated Listeria strain engineered to express HIV antigens

Induction of cell-mediated immunity may be essential for an effective AIDS vaccine. Listeria monocytogenes is an attractive bacterial vector to elicit T-cell immunity to human immunodeficiency virus (HIV) because it specifically infects monocytes, key antigen-presenting cells, and because natural infection originates at the mucosa. Immunization with recombinant L. monocytogenes has been shown to protect mice from lymphocytic choriomeningitis virus, influenza virus, and tumor inoculation. L. monocytogenes expressing HIV gag elicits sustained high levels of Gag-specific cytotoxic T lymphocytes (CTLs) in mice. We have examined the ability of Listeria to infect human monocytes and present HIV antigens to CD8 T lymphocytes of HIV-infected donors to induce a secondary T-cell immune response. Using this in vitro vaccination protocol, we show that L. monocytogenes expressing the HIV-1 gag gene efficiently provides a strong stimulus for Gag-specific CTLs in HIV-infected donor peripheral blood mononuclear cells. Listeria expressing Nef also elicits a secondary in vitro anti-Nef CTL response. Since L. monocytogenes is a pathogen, before it can be seriously considered as a human vaccine vector, safety concerns must be addressed. We therefore have produced a highly attenuated strain of L. monocytogenes that requires D-alanine for viability. The recombinant bacteria are attenuated at least 10(5)-fold. We show that when these hyperattenuated bacteria are engineered to express HIV-1 Gag, they are at least as efficient at stimulating Gag-specific human CTLs in vitro as wild-type recombinants. These results suggest that attenuated Listeria is an attractive candidate vaccine vector to induce T-cell immunity to HIV in humans.

Impaired function of circulating HIV-specific CD8(+) T cells in chronic human immunodeficiency virus infection

The functional status of circulating human immunodeficiency (HIV)-specific CD8 T cells in chronically infected subjects was evaluated. By flow cytometry, only 5 of 7 subjects had detectable CD8 T cells that produced IFN-gamma after stimulation with HIV-infected primary CD4 T cells. In 2 subjects, the frequency of IFN-gamma-producing cells increased 4-fold when IL-2 was added to the culture medium; in another subject, IFN-gamma-producing cells could be detected only after IL-2 was added. IFN-gamma-producing cells ranged from 0.4% to 3% of CD8 T cells. Major histocompatibility complex-peptide tetramer staining, which identifies antigen-specific T cells irrespective of function, was used to evaluate the proportion of HIV-specific CD8 T cells that may be nonfunctional in vivo. CD8 T cells binding to tetramers complexed to HIV gag epitope SLYNTVATL and reverse transcriptase epitope YTAFTIPSI were identified in 9 of 15 and 5 of 12 HLA-A2-expressing seropositive subjects at frequencies of 0.1% to 1.1% and 0.1 to 0.7%, respectively. Freshly isolated tetramer-positive cells expressed a mixed pattern of memory and effector markers. On average, IFN-gamma was produced by less than 25% of tetramer-positive CD8 T cells after stimulation with the relevant gag or reverse transcriptase peptide. In all subjects tested, freshly isolated CD8 T cells were not cytolytic against peptide-pulsed B lymphoblastoid cell line or primary HIV-infected CD4 T-cell targets. Exposure to IL-2 enhanced the cytotoxicity of CD8 T cells against primary HIV-infected CD4 targets in 2 of 2 subjects tested. These results suggest that a significant proportion of HIV-specific CD8 T cells may be functionally compromised in vivo and that some function can be restored by exposure to IL-2.

MOMMA. Multi-centered On-going Mothers Monitoring Algorithm for perinatal behavioral health

Depression during pregnancy and after delivery is a problem for the mother and poses a threat to the health of the fetus, the infant, and the family members. Low birth-weight babies have an increased risk for impaired cognitive function, cardiac disease, vascular disease, and diabetes. The incidence of depression during pregnancy and after delivery transforms an individual psychological problem into a problem of public health. The Multi-centered Ongoing Mothers Monitoring Algorithm for Perinatal Behavioral Health offers a structured approach to diagnosis and treatment of depression during pregnancy and after delivery. MOMMA serves as a model of care which can be offered to other hospitals.

Laryngeal manipulation

This article presents the authors' philosophy regarding the use of physical manipulation of the larynx and the neck in patients presenting with voice disorders from the context of the anatomy and physiology of the larynx. The biomechanics of the laryngeal structures are reviewed. Potential indications for manipulation are discussed. The examination of the larynx and perilaryngeal structures is presented from a mechanical standpoint. Some basic tenets in laryngeal manipulation, including potential risks and contraindications, are offered.

Electrocardiographic ST-segment changes during acute, severe isovolemic hemodilution in humans

BACKGROUND

Controversy exists regarding the lowest blood hemoglobin concentration that can be safely tolerated. The authors studied healthy resting humans to test the hypothesis that acute isovolemic reduction of blood hemoglobin concentration to 5 g/dl would produce an imbalance in myocardial oxygen supply and demand, resulting in myocardial ischemia.

METHODS

Fifty-five conscious healthy human volunteers were studied. Isovolemic removal of aliquots of blood reduced blood hemoglobin concentration from 12.8 +/- 1.2 to 5.2 +/- 0.5 g/dl (mean +/- SD). Removed blood was replaced simultaneously with intravenous fluids to maintain constant isovolemia. Hemodynamics and arterial oxygen content (Cao2) were measured before and after removal of each aliquot of blood. Electrocardiographic (ECG) changes were monitored continuously using a Holter ECG recorder for detection of myocardial ischemia.

RESULTS

During hemodilution, transient, reversible ST-segment depression developed in three subjects as seen on the electrocardiogram during hemodilution. These changes occurred at hemoglobin concentrations of 5-7 g/dl while the subjects were asymptomatic. Two of three subjects with ECG changes had significantly higher heart rates than those without ECG changes at the same hemoglobin concentrations. When evaluating the entire study period, the subjects who had ECG ST-segment changes had significantly higher maximum heart rates than those without ECG changes, despite having similar baseline values.

CONCLUSION

With acute reduction of hemoglobin concentration to 5 g/dl, ECG ST-segment changes developed in 3 of 55 healthy conscious adults and were suggestive of, but not conclusive for, myocardial ischemia. The higher heart rates that developed during hemodilution may have contributed to the development of an imbalance between myocardial supply and demand resulting in ECG evidence of myocardial ischemia. However, these ECG changes appear to be benign because they were reversible and not accompanied by symptoms.

Efficacy and safety of troglitazone in the treatment of lipodystrophy syndromes

BACKGROUND

Troglitazone promotes adipocyte differentiation in vitro and increases insulin sensitivity in vivo. Therefore, troglitazone may have therapeutic benefit in lipoatrophic diabetes.

OBJECTIVE

To determine whether troglitazone ameliorates hyperglycemia and hypertriglyceridemia or increases fat mass in lipoatrophic patients.

DESIGN

Open-labeled prospective study.

SETTING

United States and Canada.

PATIENTS

20 patients with various syndromes associated with lipoatrophy or lipodystrophy.

INTERVENTION

6 months of therapy with troglitazone, 200 to 600 mg/d.

MEASUREMENTS

Levels of hemoglobin A1c triglycerides, free fatty acids, and insulin; respiratory quotient; percentage of body fat; liver volume; and regional fat mass.

RESULTS

In the 13 patients with diabetes who completed 6 months of troglitazone therapy, hemoglobin A1c levels decreased by a mean of 2.8% (95% CI, 1.9% to 3.7%; P < 0.001). In all 19 study patients, fasting triglyceride levels decreased by 2.6 mmol/L (230 mg/dL) (CI, 0.7 to 4.5 mmol/L [62 to 398 mg/dL]; P = 0.019) and free fatty acid levels decreased by 325 micromol/L (CI, 135 to 515 micromol/L; P = 0.035). The respiratory quotient decreased by a mean of 0.12 (CI, 0.08 to 0.16; P < 0.001), suggesting that troglitazone promoted oxidation of fat. Body fat increased by a mean of 2.4 percentage points (CI, 1.3 to 4.5 percentage points; P = 0.044). Magnetic resonance imaging showed an increase in subcutaneous adipose tissue but not in visceral fat. In one patient, the serum alanine aminotransferase level increased eightfold during the 10th months of troglitazone treatment but normalized 3 months after discontinuation of treatment Liver biopsy revealed an eosinophilic infiltrate, suggesting hypersensitivity reaction as a cause of hepatotoxicity.

CONCLUSION

Troglitazone therapy improved metabolic control and increased body fat in patients with lipoatrophic diabetes. The substantial benefits of troglitazone must be balanced against the risk for hepatotoxicity, which can occur relatively late in the treatment course.

Human immunodeficiency virus-specific circulating CD8 T lymphocytes have down-modulated CD3zeta and CD28, key signaling molecules for T-cell activation

Although human immunodeficiency virus (HIV)-infected subjects without AIDS have a high frequency of HIV-specific CD8 T lymphocytes, cellular immunity is unable to control infection. Freshly isolated lymphocytes often do not lyse HIV-infected targets in 4-h cytotoxicity assays. A large fraction of circulating CD8 T cells from HIV-infected donors down-modulate CD3zeta, the signaling component of the T-cell receptor complex, which is reexpressed in vitro coincident with the return of cytotoxic function. To investigate further the link between CD3zeta down-modulation and possible CD8 T-cell functional defects, we used flow cytometry to characterize further the properties of the CD3zeta-down-modulated subset. HIV-specific CD8 T cells, identified by tetramer staining, are CD3zeta(-). CD8 T cells with down-modulated CD3zeta also do not express the key costimulatory receptor CD28 and have the cell surface phenotype of activated or memory T cells (HLA-DR(+) CD62L(-)). After T-cell activation, CD3zeta-down-modulated cells express the activation marker CD69 but not the high-affinity interleukin 2 (IL-2) receptor alpha-chain CD25 and produce gamma interferon but not IL-2. Therefore HIV-specific CD8 T cells have down-modulated key signaling molecules for T-cell activation and costimulation and require exogenous cytokine stimulation. The typical impairment of HIV-specific CD4 T helper cells, which would normally provide specific CD8 T-cell stimulation, means that in vivo CTL function in vivo is compromised in most HIV-infected individuals. In AIDS patients, the functional defect is more severe, since CD3zeta is not reexpressed even after IL-2 exposure.

CD3zeta and CD28 down-modulation on CD8 T cells during viral infection

Down-modulation of CD3zeta expression on CD8 T lymphocytes occurs, independently of other T-cell receptor (TCR)-CD3 components, in tumor-infiltrating lymphocytes, human immunodeficiency virus infection, and autoimmune disease. These associations suggest that it might be related to chronic antigenic stimulation. CD3zeta down-modulation was found, however, in CD8 T cells that proliferate in response to acute viral infections. In 3 otherwise healthy donors with acute gastroenteritis, infectious mononucleosis, and Epstein-Barr virus/cytomegalovirus/mononucleosis, 30% to 60% of circulating CD8 T cells had down-modulated CD3zeta to below the level of detection. The CD3zeta-T cells were also CD28- but expressed the activation markers HLA-DR and CD57. CD3zeta-CD28- T cells are effector CTL because they express perforin and produce IFN-gamma, but not IL-2, on activation and contain the viral-specific cytotoxic T lymphocyte (CTL). However, CD3zeta-CD28-T cells generally do not express CD25 after anti-CD3 and anti-CD28 stimulation and are not cytotoxic until they are cultured with IL-2 overnight. Cytotoxicity coincides with the re-expression of CD3zeta but not CD28. Down-modulation of CD3zeta and CD28 on effector CTL may control CTL triggering and proliferation to prevent immunopathogenesis.

Genetically modified anthrax lethal toxin safely delivers whole HIV protein antigens into the cytosol to induce T cell immunity

Bacillus anthrax lethal toxin can be engineered to deliver foreign proteins to the cytosol for antigen presentation to CD8 T cells. Vaccination with modified toxins carrying 8-9 amino acid peptide epitopes induces protective immunity in mice. To evaluate whether large protein antigens can be used with this system, recombinant constructs encoding several HIV antigens up to 500 amino acids were produced. These candidate HIV vaccines are safe in animals and induce CD8 T cells in mice. Constructs encoding gag p24 and nef stimulate gag-specific CD4 proliferation and a secondary cytotoxic T lymphocyte response in HIV-infected donor peripheral blood mononuclear cells in vitro. These results lay the foundation for future clinical vaccine studies.