Antigen-driven CD8 + T cell clonal expansion is a prominent feature of MASH in humans and mice

Background and Aims

Chronic liver disease due to metabolic dysfunction-associated steatohepatitis (MASH) is a rapidly increasing global epidemic. MASH progression is a consequence of the complex interplay between inflammatory insults and dysregulated hepatic immune responses. T lymphocytes have been shown to accumulate in the liver during MASH, but the cause and consequence of T cell accumulation in the liver remain unclear. Our study aimed to define the phenotype and T cell receptor diversity of T cells from human cirrhotic livers and an animal model of MASH to begin resolving their function in disease.

Approach and Results

In these studies, we evaluated differences in T cell phenotype in the context of liver disease we isolated liver resident T cell populations from individuals with cirrhosis and a murine model of MASH. Using both 5' single cell sequencing and flow cytometry we defined the phenotype and T cell receptor repertoire of liver resident T cells during health and disease.

Conclusions

MASH-induced cirrhosis and diet-induced MASH in mice resulted in the accumulation of activated and clonally expanded T cells in the liver. The clonally expanded T cells in the liver expressed markers of chronic antigenic stimulation, including PD1 , TIGIT and TOX . Overall, this study establishes for the first time that T cells undergo antigen-dependent clonal expansion and functional differentiation during the progression of MASH. These studies could lead to the identification of potential antigenic targets that drive T cell activation, clonal expansion, and recruitment to the liver during MASH.

Outcomes of Preperitoneal Packing and Angioembolization for Hemorrhage Control in Hemodynamically Unstable Pelvic Fractures: A Systematic Review and Meta-Analysis

BACKGROUND

Hemodynamically unstable pelvic fractures are often life-threatening injuries; however, the optimal management remains uncertain. This systematic review and meta-analysis aim to evaluate the most appropriate primary management of hemorrhage in adult patients with hemodynamically unstable pelvic fractures by comparing outcomes following the initial use of preperitoneal packing (PPP) vs angioembolization (AE).

METHODS

A systematic search of PubMed, Embase, Google Scholar, and ProQuest databases was conducted following PRISMA guidelines. Studies assessing hemorrhage management in trauma patients with hemodynamically unstable pelvic fractures were included. The data extracted from selected articles included patient demographics, study design, and outcomes such as 24-hour PRBC transfusions, in-hospital mortality, and DVT rate.

RESULTS

Eight articles were included in the systematic review. Among the included studies, 2040 patients with hemodynamically unstable pelvic fractures were analyzed. Meta-analyses revealed that treatment with PPP was associated with fewer 24-hour PRBC transfusions (mean difference = -1.0, 95% CI: -1.8 to -.2) than AE. However, no significant differences were noted in in-hospital mortality (RR: .91, 95% CI: .80-1.05) and the rate of deep vein thrombosis (RR: .89, 95% CI: .62-1.28) between groups.

CONCLUSION

The findings of this study suggest that primary management with PPP was associated with fewer 24-hour PRBC transfusions compared to AE. The choice of primary management with PPP or AE did not significantly impact in-hospital mortality. Future studies should address clinical outcomes and the factors that affect them to better understand the impact of different management strategies and direct the creation of practice management guidelines.

The Association Between Gender and Clinical Outcomes in Patients With Moderate to Severe Traumatic Brain Injury: A Systematic Review and Meta-Analysis

INTRODUCTION

Traumatic brain injuries (TBIs) are a significant cause of morbidity and mortality in the United States. but have a disproportionate impact on patients based on gender. This systematic review and meta-analysis aim to compare gender differences in clinical outcomes between male and female adult trauma patients with moderate and severe TBI.

METHODS

Studies assessing gender differences in outcomes following TBIs on PubMed, Google Scholar, EMBASE, and ProQuest were searched. Meta-analysis was performed for outcomes including in-hospital mortality, hospital length of stay, intensive care unit length of stay, and Glasgow outcome scale (GOS) at 6 mo.

RESULTS

Eight studies were included for analysis with 26,408 female and 63,393 male patients. Meta-analysis demonstrated that males had a significantly lower risk of mortality than females (RR: 0.88; 95% CI 0.78, 0.99; P = 0.0001). Females had a shorter hospital length of stay (mean difference -1.4 d; 95% CI - 1.6 d, -1.2 d). No significant differences were identified in intensive care unit length of stay (mean difference -3.0 d; 95% CI -7.0 d, 1.1 d; P = 0.94) or GOS at 6 mo (mean difference 0.2 d; 95% CI -0.9 d, 1.4 d; P = 1).

CONCLUSIONS

Compared to male patients, female patients with moderate and severe TBI had a significantly higher in-hospital mortality risk. There were no significant differences in long-term outcomes between genders based on GOS at 6 mo. These findings warrant further investigation into the etiology of these gender disparities and their impact on additional clinical outcome measures.

Evaluating Clinical Outcomes of Laparoscopic Subtotal and Total Cholecystectomy for Complicated Acute Cholecystitis: A Systematic Review and Meta-Analysis

INTRODUCTION

This systematic review and meta-analysis aimed to compare clinical outcomes in patients with complicated acute cholecystitis undergoing laparoscopic total vs subtotal cholecystectomy.

METHODS

This systematic review and meta-analysis was conducted according to PRISMA guidelines and queried PubMed, Embase, ProQuest, Google Scholar, and Cochrane databases from inception to May 2023. The primary outcome was complication rates including common bile duct injury, wound infection, reoperation, bile leak, retained stones, and subhepatic collection, whereas secondary outcomes were in-hospital mortality and hospital length of stay.

RESULTS

A total of 7 studies with 135,233 cases were included for meta-analysis. Patients who underwent laparoscopic total cholecystectomy had a significantly lower risk of postoperative bile leaks (RR: .15; 95% CI: .03, .80) and subhepatic fluid collection (RR: 0.19; 95% CI: .06, .63) and were 2.94 times less likely to die compared to those who underwent subtotal cholecystectomy (RR .34; 95% CI: .15, .77). Patients who underwent subtotal cholecystectomy had significantly longer hospital length of stay (mean difference 1.0 days; 95% CI: .5 days, 1.4 days).

CONCLUSIONS

In adult patients presenting with complicated cholecystitis, management with laparoscopic subtotal cholecystectomy presents a unique complication profile with increased risk of postoperative bile leak and subhepatic fluid collection, in-hospital mortality, and longer hospital length-of-stay when used as an alternative approach to laparoscopic total cholecystectomy. Further research into the most appropriate clinical scenarios and patient populations for the use of the subtotal cholecystectomy approach may prove useful in improving its associated outcomes.

Assessing the ecological risk of heavy metal sediment contamination from Port Everglades Florida USA

Port sediments are often contaminated with metals and organic compounds from anthropogenic sources. Remobilization of sediment during a planned expansion of Port Everglades near Fort Lauderdale, Florida (USA) has the potential to harm adjacent benthic communities, including coral reefs. Twelve sediment cores were collected from four Port Everglades sites and a control site; surface sediment was collected at two nearby coral reef sites. Sediment cores, sampled every 5 cm, were analyzed for 14 heavy metals using inductively coupled plasma-mass spectrometry. Results for all three locations yielded concentration ranges (µg/g): As (0.607-223), Cd (n/d-0.916), Cr (0.155-56.8), Co (0.0238-7.40), Cu (0.004-215), Pb (0.0169-73.8), Mn (1.61-204), Hg (n/d-0.736), Mn (1.61-204), Ni (0.232-29.3), Se (n/d-4.79), Sn (n/d-140), V (0.160-176), and Zn (0.112-603), where n/d = non-detected. The geo-accumulation index shows moderate-to-strong contamination of As and Mo in port sediments, and potential ecological risk indicates moderate-to-significantly high overall metal contamination. All four port sites have sediment core subsamples with As concentrations above both threshold effect level (TEL, 7.24 µg/g) and probable effect level (PEL, 41.6 µg/g), while Mo geometric mean concentrations exceed the background continental crust level (1.5 µg/g) threshold. Control site sediments exceed TEL for As, while the reef sites has low to no overall heavy metal contamination. Results of this study indicate there is a moderate to high overall ecological risk from remobilized sediment due to metal contamination. Due to an imminent dredging at Port Everglades, this could have the potential to harm the threatened adjacent coral communities and surrounding protected habitats.

The Parallel Structure-Activity Relationship Screening of Three Compounds Identifies the Common Agonist Pharmacophore of Pyrrolidine Bis-Cyclic Guanidine Melanocortin-3 Receptor (MC3R) Small-Molecule Ligands

The melanocortin receptors are involved in numerous physiological pathways, including appetite, skin and hair pigmentation, and steroidogenesis. In particular, the melanocortin-3 receptor (MC3R) is involved in fat storage, food intake, and energy homeostasis. Small-molecule ligands developed for the MC3R may serve as therapeutic lead compounds for treating disease states of energy disequilibrium. Herein, three previously reported pyrrolidine bis-cyclic guanidine compounds with five sites for molecular diversity (R1-R5) were subjected to parallel structure-activity relationship studies to identify the common pharmacophore of this scaffold series required for full agonism at the MC3R. The R2, R3, and R5 positions were required for full MC3R efficacy, while truncation of either the R1 or R4 positions in all three compounds resulted in full MC3R agonists. Two additional fragments, featuring molecular weights below 300 Da, were also identified that possessed full agonist efficacy and micromolar potencies at the mMC5R. These SAR experiments may be useful in generating new small-molecule ligands and chemical probes for the melanocortin receptors to help elucidate their roles in vivo and as therapeutic lead compounds.

Outcomes of Transfusion With Whole Blood, Component Therapy, or Both in Adult Civilian Trauma Patients: A Systematic Review and Meta-Analysis

INTRODUCTION

This systematic review and meta-analysis was conducted to compare outcomes, including transfusion volume, complications, intensive care unit length of stay, and mortality for adult civilian trauma patients transfused with whole blood (WB), components (COMP), or both (WB + COMP).

METHODS

A systematic review and meta-analysis were conducted using studies that evaluated outcomes of transfusion of WB, COMP, or WB + COMP for adult civilian trauma patients. A search of PubMed, Embase, and Cochrane from database inception to March 3, 2022 was conducted. The search resulted in 18,400 initial articles with 16 studies remaining after the removal of duplicates and screening for inclusion and exclusion criteria.

RESULTS

This study identified an increased risk of 24-h mortality with COMP versus WB + COMP (relative risk: 1.40 [1.10, 1.78]) and increased transfusion volumes of red blood cells with COMP versus WB at 6 and 24 h, respectively (-2.26 [-3.82, -0.70]; -1.94 [-3.22, -0.65] units). There were no differences in the calculated rates of infections or intensive care unit length of stay between WB and COMP, respectively (relative risks: 1.35 [0.53, 3.46]; -0.91 [-2.64, 0.83]).

CONCLUSIONS

Transfusion with WB + COMP is associated with lower 24-h mortality versus COMP and transfusion with WB is associated with a lower volume of red blood cells transfused at both 6 and 24 h. Based on these findings, greater utilization of whole blood in civilian adult trauma resuscitation may lead to improved mortality and reduced transfusion requirements.

Comparing Outcomes of Appendectomy Versus Non-operative Antibiotic Therapy for Acute Appendicitis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

Acute appendicitis is one of the most common etiologies of an acute abdomen in the emergency department and first-line standard surgical care for the condition has recently been reconsidered. We aim to evaluate the effectiveness and outcomes of surgical intervention versus non-operative antibiotic therapy in the treatment of acute appendicitis in adult and pediatric patients.

METHODS

A literature search was conducted using PubMed, Google Scholar, and EMBASE. The search included all studies until January 15th, 2022. Preferred Reporting Items for Systematic reviews and Meta-Analysis guidelines were followed for abstracting data and assessing data quality and validity. Data were independently extracted by the authors of the study. Meta-analysis was performed and Cohen's Q test for heterogeneous effects was performed to determine if fixed or random-effects models were appropriate for use.

RESULTS

Twelve randomized controlled trials investigating a total of 3703 acute appendicitis patients met inclusion criteria and were included in the meta-analysis. In the systematic review, eleven RCTs demonstrated that appendectomy had improved effectiveness compared to non-operative antibiotic management. The meta-analysis demonstrated that patients undergoing appendectomy had significantly higher treatment effectiveness compared with antibiotics-only treatment (98.4% vs. 73.3%, P < .0001). The meta-analysis did demonstrate a significant .54-day reduction in hospital length of stay for the appendectomy group compared to the non-operative antibiotic therapy group.

CONCLUSIONS

Surgical intervention is associated with increased effectiveness of treatment and reduced in-hospital length of stay among patients with acute appendicitis. Guidelines established by institutions and surgical organizations should indicate appendectomy as the standard and superior treatment option for patients presenting with acute appendicitis.

Beta-Blocker Therapy in Patients With Severe Traumatic Brain Injury: A Systematic Review and Meta-Analysis

INTRODUCTION

Traumatic brain injury (TBI), a leading cause of morbidity and mortality among trauma patients worldwide, poses the risk of secondary neurological insult due to significant catecholamine surge. We aim to investigate the effectiveness and outcomes of beta-blocker administration in patients with severe TBI.

METHODS

A search through PubMed, EMBASE, JAMA network, and Google Scholar databases was conducted for relevant peer-reviewed original studies published before February 15, 2022. A standard random-effects model was used, as justified by a high Cohen's Q test.

RESULTS

Twelve studies met inclusion criteria and were included in the meta-analysis. Severe TBI patients who were administered beta-blockers had a significantly reduced incidence of in-hospital mortality compared to the non-beta-blocker group (14.5% vs 19.2%). However, the beta-blocker group was reported to have a significantly greater number of ventilator days (5.58 vs 2.60 days). Similarly, intensive care unit (9.00 vs 6.84 days) and hospital (17.30 vs 11.02 days) lengths of stay (LOS) were increased in the beta-blocker group compared to those who were not administered beta-blocker therapy, but only the difference in hospital-LOS was significant.

CONCLUSIONS

Beta-blockers have significantly decreased in-hospital mortality in patients with severe TBI despite being associated with an increase in ventilator days and hospital-LOS. The administration of beta-blocker therapy in the management of severe TBI may be warranted and should be discussed in future guidelines.

Identification of B Cell and T Cell Epitopes Using Synthetic Peptide Combinatorial Libraries

This article presents a combinatorial library method that consists of the synthesis and screening of mixture-based synthetic combinatorial libraries of peptide molecules to identify B and T cell epitopes. The protocols employ peptide libraries to identify peptides recognized by MAbs and T cells. The first protocol uses a positional scanning peptide library made up of hexapeptides to identify antigenic determinants recognized by MAbs. The 120 mixtures in the hexapeptide library are tested for their inhibitory activity in a competitive ELISA. The second protocol uses a decapeptide library to identify T cell peptide ligands. The 200 mixtures of the decapeptide library are tested for their ability to induce T cell activation. Support protocols cover optimization of the assay conditions for each MAb or T cell, to achieve the best level of sensitivity and reproducibility, and preparation of a hexapeptide library, along with deconvolution approaches. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Screening peptide library for antibody inhibition Basic Protocol 2: Screening a peptide library to identify CD4⁺ Or CD8⁺ T cell ligands Support Protocol 1: Optimizing antigen and antibody concentrations for screening assay Support Protocol 2: Preparing a positional scanning peptide library.

Healthcare Understanding of COVID-19 Antibody

Objective

: The SARS-CoV-2 pandemic has shed light on the difficulties in spreading uniform information. We rely on national and international organizations to provide scientifically accurate information to the public at large. With so many different sources of information, often not scientific, there appears to be an incomplete understanding of many aspects of SARS-CoV-2 infection. We sought to gain information about healthcare worker understanding of the implications of a positive serum COVID-19 antibody test result. We identified a broad range of responses among all categories of healthcare workers in our facility. Most notably we found that there was not complete understanding that there can be asymptomatic spread of COVID-19 infection.

Methods

: We provided health literacy and opinion questions to the healthcare workers of our facility.

Results

: Upon analysis of the data, we identified many differences in level of understanding among our healthcare workers.

Conclusion

: We identified a lack of consensus on important details leading to potentially growing uncertainty with respect to SARS-COV-2 antibody. A diminished health literacy with respect to antibody testing could potentially suggest future issues with understanding the importance of vaccination benefits.

Functional Mixture-Based Positional Scan Identifies a Library of Antagonist Tetrapeptide Sequences (LAtTeS) with Nanomolar Potency for the Melanocortin-4 Receptor and Equipotent with the Endogenous AGRP(86-132) Antagonist

The melanocortin-4 receptor (MC4R) plays an important role in appetite. Agonist ligands that stimulate the MC4R decrease appetite, while antagonist compounds increase food consumption. Herein, a functional mixture-based positional scan identified novel MC4R antagonist sequences. Mixtures comprising a library of 12,960,000 tetrapeptides were screened in the presence and absence of the NDP-MSH agonist. These results led to the synthesis of 48 individual tetrapeptides, of which 40 were screened for functional activity at the melanocortin receptors. Thirteen compounds were found to possess nanomolar antagonist potency at the MC4R, with the general tetrapeptide sequence Ac-Aromatic-Basic-Aromatic-Basic-NH₂. The most notable results include the identification of tetrapeptide 48 [COR1-25, Ac-DPhe(pI)-Arg-Nal(2')-Arg-NH₂], an equipotent MC4R antagonist to agouti-related protein [AGRP(86-132)], more potent than miniAGRP(87-120), and possessing 15-fold selectivity for the MC4R versus the MC3R. These tetrapeptides may serve as leads for novel appetite-inducing therapies to treat states of negative energy balance, such as cachexia and anorexia.

CD4+ T cells in the lungs of acute sarcoidosis patients recognize an Aspergillus nidulans epitope

Löfgren’s syndrome (LS) is an acute form of sarcoidosis characterized by a genetic association with HLA-DRB1*03 (HLA-DR3) and an accumulation of CD4⁺ T cells of unknown specificity in the bronchoalveolar lavage (BAL). Here, we screened related LS-specific TCRs for antigen specificity and identified a peptide derived from NAD-dependent histone deacetylase hst4 (NDPD) of Aspergillus nidulans that stimulated these CD4⁺ T cells in an HLA-DR3–restricted manner. Using ELISPOT analysis, a greater number of IFN-γ– and IL-2–secreting T cells in the BAL of DR3⁺ LS subjects compared with DR3⁺ control subjects was observed in response to the NDPD peptide. Finally, increased IgG antibody responses to A. nidulans NDPD were detected in the serum of DR3⁺ LS subjects. Thus, our findings identify a ligand for CD4⁺ T cells derived from the lungs of LS patients and suggest a role of A. nidulans in the etiology of LS.

Single cell analysis of host response to helminth infection reveals the clonal breadth, heterogeneity, and tissue-specific programming of the responding CD4+ T cell repertoire

The CD4⁺ T cell response is critical to host protection against helminth infection. How this response varies across different hosts and tissues remains an important gap in our understanding. Using IL-4-reporter mice to identify responding CD4⁺ T cells to Nippostrongylus brasiliensis infection, T cell receptor sequencing paired with novel clustering algorithms revealed a broadly reactive and clonally diverse CD4⁺ T cell response. While the most prevalent clones and clonotypes exhibited some tissue selectivity, most were observed to reside in both the lung and lung-draining lymph nodes. Antigen-reactivity of the broader repertoires was predicted to be shared across both tissues and individual mice. Transcriptome, trajectory, and chromatin accessibility analysis of lung and lymph-node repertoires revealed three unique but related populations of responding IL-4⁺ CD4⁺ T cells consistent with T follicular helper, T helper 2, and a transitional population sharing similarity with both populations. The shared antigen reactivity of lymph node and lung repertoires combined with the adoption of tissue-specific gene programs allows for the pairing of cellular and humoral responses critical to the orchestration of anti-helminth immunity.

Using various “omic” approaches, the CD4⁺ T cell receptor (TCR) repertoire was explored after primary helminth infection. Infection generated a broadly reactive and clonally diverse CD4⁺ T cell response with the most prevalent clonotypes and predicted antigen specificities residing in both the lung and lung-draining lymph nodes. Tissue-specific programming of responding CD4⁺ T cells directed the establishment of committed Tfh and Th2 cells, both critical for driving distinct hallmarks of type-2 inflammation. These datasets help to explore the diverse yet tissue-specific nature of anti-helminth immunity.

Association of hypothermia with increased mortality rate in SARS-CoV-2 infection

OBJECTIVE

Patients were observed to have variable temperatures. The objective of this study was to identify whether hypothermia in a patient infected with SARS-CoV-2 was associated with a higher than expected mortality.

METHODS

In total, 331 charts from patients hospitalized with SARS-CoV-2 between March 9 and April 20, 2020 were reviewed.

RESULTS

The probability of death was 2.06 times higher for those with hypothermia than for those without (95% CI 1.25-3.38)]. In ventilated patients, there were 32 deaths. Of these, 75% had been hypothermic. In a prior review of 10 000 non-SARS-CoV-2 patients with sepsis, the mortality rate in patients with hypothermia was 47%. A review of previous studies demonstrated a range of expected mortality rates in patients with ventilator-dependent respiratory failure and sepsis. In comparison, our study showed that within a group of critically ill patients with SARS-CoV-2 and hypothermia, the mortality rate exceeded those rates.

CONCLUSION

Our review showed a significant association between hypothermia and death (p = 0.0033). Predictors of mortality in SARS-CoV-2 disease can expedite earlier aggressive care. Additionally, in areas with limited resources or overburdened healthcare systems, where there may be a need for resource allocation management, information about mortality risk may be helpful.

Beryllium-specific CD4+ T cells induced by chemokine neoantigens perpetuate inflammation

Discovering dominant epitopes for T cells, particularly CD4+ T cells, in human immune-mediated diseases remains a significant challenge. Here, we used bronchoalveolar lavage (BAL) cells from HLA-DP2-expressing patients with chronic beryllium disease (CBD), a debilitating granulomatous lung disorder characterized by accumulations of beryllium-specific (Be-specific) CD4+ T cells in the lung. We discovered lung-resident CD4+ T cells that expressed a disease-specific public CDR3β T cell receptor motif and were specific to Be-modified self-peptides derived from C-C motif ligand 4 (CCL4) and CCL3. HLA-DP2-CCL/Be tetramer staining confirmed that these chemokine-derived peptides represented major antigenic targets in CBD. Furthermore, Be induced CCL3 and CCL4 secretion in the lungs of mice and humans. In a murine model of CBD, the addition of LPS to Be oxide exposure enhanced CCL4 and CCL3 secretion in the lung and significantly increased the number and percentage of CD4+ T cells specific for the HLA-DP2-CCL/Be epitope. Thus, we demonstrate a direct link between Be-induced innate production of chemokines and the development of a robust adaptive immune response to those same chemokines presented as Be-modified self-peptides, creating a cycle of innate and adaptive immune activation.

Discovery of Nanomolar Melanocortin-3 Receptor (MC3R)-Selective Small Molecule Pyrrolidine Bis-Cyclic Guanidine Agonist Compounds Via a High-Throughput "Unbiased" Screening Campaign

The central melanocortin-3 and melanocortin-4 receptors (MC3R, MC4R) are key regulators of body weight and energy homeostasis. Herein, the discovery and characterization of first-in-class small molecule melanocortin agonists with selectivity for the melanocortin-3 receptor over the melanocortin-4 receptor are reported. Identified via "unbiased" mixture-based high-throughput screening approaches, pharmacological evaluation of these pyrrolidine bis-cyclic guanidines resulted in nanomolar agonist activity at the melanocortin-3 receptor. The pharmacological profiles at the remaining melanocortin receptor subtypes tested indicated similar agonist potencies at both the melanocortin-1 and melanocortin-5 receptors and antagonist or micromolar agonist activities at the melanocortin-4 receptor. This group of small molecules represents a new area of chemical space for the melanocortin receptors with mixed receptor pharmacology profiles that may serve as novel lead compounds to modulate states of dysregulated energy balance.

A Randomized Double-Blind Placebo-Controlled Phase II Trial of Dendritic Cell Vaccine ICT-107 in Newly Diagnosed Patients with Glioblastoma

PURPOSE

To evaluate the results of the randomized, double-blind, placebo-controlled phase II clinical trial of ICT-107 in patients with newly diagnosed glioblastoma.

PATIENTS AND METHODS

We conducted a double-blinded randomized phase II trial of ICT-107 in newly diagnosed patients with glioblastoma (GBM) and tested efficacy, safety, quality of life (QoL), and immune response. HLA-A1⁺ and/or -A2⁺-resected patients with residual tumor ≤1 cm³ received radiotherapy and concurrent temozolomide. Following completion of radiotherapy, 124 patients, randomized 2:1, received ICT-107 [autologous dendritic cells (DC) pulsed with six synthetic peptide epitopes targeting GBM tumor/stem cell-associated antigens MAGE-1, HER-2, AIM-2, TRP-2, gp100, and IL13Rα2] or matching control (unpulsed DC). Patients received induction ICT-107 or control weekly × 4 followed by 12 months of adjuvant temozolomide. Maintenance vaccinations occurred at 1, 3, and 6 months and every 6 months thereafter.

RESULTS

ICT-107 was well tolerated, with no difference in adverse events between the treatment and control groups. The primary endpoint, median overall survival (OS), favored ICT-107 by 2.0 months in the intent-to-treat (ITT) population but was not statistically significant. Progression-free survival (PFS) in the ITT population was significantly increased in the ICT-107 cohort by 2.2 months (P = 0.011). The frequency of HLA-A2 primary tumor antigen expression was higher than that for HLA-A1 patients, and HLA-A2 patients had higher immune response (via Elispot). HLA-A2 patients achieved a meaningful therapeutic benefit with ICT-107, in both the MGMT methylated and unmethylated prespecified subgroups, whereas only HLA-A1 methylated patients had an OS benefit.

CONCLUSIONS

PFS was significantly improved in ICT-107-treated patients with maintenance of QoL. Patients in the HLA-A2 subgroup showed increased ICT-107 activity clinically and immunologically.

Discovery of Polypharmacological Melanocortin-3 and -4 Receptor Probes and Identification of a 100-Fold Selective nM MC3R Agonist versus a μM MC4R Partial Agonist

The centrally expressed melanocortin-3 and melanocortin-4 receptors (MC3R and MC4R, respectively) are established targets to treat diseases of positive- and negative-energy homeostasis. We previously reported [ Doering , S. R. ; J. Med. Chem. 2017 , 60 , 4342 - 4357 ] mixture-based positional scanning approaches to identify dual MC3R agonist and MC4R antagonist tetrapeptides. Herein, 46 tetrapeptides were chosen for MC3R agonist screening selectivity profiles, synthesized, and pharmacologically characterized at the mouse melanocortin-1, -3, -4, and -5 receptors. Substitutions to the tetrapeptide template were selected solely based on MC3R agonist potency from the mixture-based screen. This study resulted in the discovery of compound 42 (Ac-Val-Gln-(pI)DPhe-DTic-NH₂), a full MC3R agonist that is 100-fold selective for the MC3R over the μM MC4R partial agonist pharmacology. This compound represents a first-in-class MC3R selective agonist. This ligand will serve as a useful in vivo molecular probe for the investigation of the roles of the MC3R and MC4R in diseases of dysregulated energy homeostasis.

Scaffold Ranking and Positional Scanning Identify Novel Neurite Outgrowth Promoters with Nanomolar Potency

Central nervous system (CNS) neurons typically fail to regrow their axons after injury. Injuries or neuropathies that damage CNS axons and disrupt neuronal circuitry often result in permanent functional deficits. Axon regeneration is therefore an intensely pursued therapeutic strategy for numerous CNS disorders. Phenotypic screens utilizing primary neurons have proven successful at identifying agents that promote axon regeneration in vivo. Here, we report the screening of mixture-based combinatorial small molecule libraries in a phenotypic assay utilizing primary CNS neurons and the discovery of neurite outgrowth promoters with low nanomolar potency.

Identification of a Novel Polyamine Scaffold With Potent Efflux Pump Inhibition Activity Toward Multi-Drug Resistant Bacterial Pathogens

We have previously reported the use of combinatorial chemistry to identify broad-spectrum antibacterial agents. Herein, we extend our analysis of this technology toward the discovery of anti-resistance molecules, focusing on efflux pump inhibitors. Using high-throughput screening against multi-drug resistant Pseudomonas aeruginosa, we identified a polyamine scaffold that demonstrated strong efflux pump inhibition without possessing antibacterial effects. We determined that these molecules were most effective with an amine functionality at R1 and benzene functionalities at R2 and R3. From a library of 188 compounds, we studied the properties of 5 lead agents in detail, observing a fivefold to eightfold decrease in the 90% effective concentration of tetracycline, chloramphenicol, and aztreonam toward P. aeruginosa isolates. Additionally, we determined that our molecules were not only active toward P. aeruginosa, but toward Acinetobacter baumannii and Staphylococcus aureus as well. The specificity of our molecules to efflux pump inhibition was confirmed using ethidium bromide accumulation assays, and in studies with strains that displayed varying abilities in their efflux potential. When assessing off target effects we observed no disruption of bacterial membrane polarity, no general toxicity toward mammalian cells, and no inhibition of calcium channel activity in human kidney cells. Finally, combination treatment with our lead agents engendered a marked increase in the bactericidal capacity of tetracycline, and significantly decreased viability within P. aeruginosa biofilms. As such, we report a unique polyamine scaffold that has strong potential for the future development of novel and broadly active efflux pump inhibitors targeting multi-drug resistant bacterial infections.

High-Throughput Flow Cytometry Screening of Multidrug Efflux Systems

The resistance nodulation cell division (RND) family of proteins are inner membrane transporters that associate with periplasmic adaptor proteins and outer membrane porins to affect substrate transport from the cytosol and periplasm in Gram-negative bacteria. Various structurally diverse compounds are substrates of RND transporters. Along with their notable role in antibiotic resistance, these transporters are essential for niche colonization, quorum sensing, and virulence as well as for the removal of fatty acids and bile salts. As such, RNDs are an attractive target for antimicrobial development. However, while enhancing the utility of antibiotics with an RND inhibitor is an appealing concept, only a small core of chemotypes has been identified as efflux pump inhibitors (EPIs). Thus, our key objective is the development and validation of an efflux profiling and discovery strategy for RND model systems. Here we describe a flow cytometric dye accumulation assay that uses fluorescein diacetate (FDA) to interrogate the model Gram-negative pathogens Escherichia coli, Franscisella tularensis, and Burkholderia pseudomallei. Fluorochrome retention is increased in the presence of known efflux inhibitors and in RND deletion strains. The assay can be used in a high-throughput format to evaluate efflux of dye-substrate candidates and to screen chemical libraries for novel EPIs. Triaged compounds that inhibit efflux in pathogenic strains are tested for growth inhibition and antibiotic potentiation using microdilution culture plates in a select agent Biosafety Level-3 (BSL3) environment. This combined approach demonstrates the utility of flow cytometric analysis for efflux activity and provides a useful platform in which to characterize efflux in pathogenic Gram-negative bacteria. Screening small molecule libraries for novel EPI candidates offers the potential for the discovery of new classes of antibacterial compounds.

Identification of Protein Palmitoylation Inhibitors from a Scaffold Ranking Library

The addition of palmitoyl moieties to proteins regulates their membrane targeting, subcellular localization, and stability. Dysregulation of the enzymes which catalyzed the palmitoyl addition and/or the substrates of these enzymes have been linked to cancer, cardiovascular, and neurological disorders, implying these enzymes and substrates are valid targets for pharmaceutical intervention. However, current chemical modulators of zDHHC PAT enzymes lack specificity and affinity, underscoring the need for screening campaigns to identify new specific, high affinity modulators. This report describes a mixture based screening approach to identify inhibitors of Erf2 activity. Erf2 is the Saccharomyces cerevisiae PAT responsible for catalyzing the palmitoylation of Ras2, an ortholog of the human Ras oncogene proteins. A chemical library developed by the Torrey Pines Institute for Molecular Studies consists of more than 30 million compounds designed around 68 molecular scaffolds that are systematically arranged into positional scanning and scaffold ranking formats. We have used this approach to identify and characterize several scaffold backbones and R-groups that reduce or eliminate the activity of Erf2 in vitro. Here, we present the analysis of one of the scaffold backbones, bis-cyclic piperazine. We identified compounds that inhibited Erf2 auto-palmitoylation activity using a fluorescence-based, coupled assay in a high throughput screening (HTS) format and validated the hits utilizing an orthogonal gel-based assay. Finally, we examined the effects of the compounds on cell growth in a yeast cell-based assay. Based on our results, we have identified specific, high affinity palmitoyl transferase inhibitors that will serve as a foundation for future compound design.

Discovery of Mixed Pharmacology Melanocortin-3 Agonists and Melanocortin-4 Receptor Tetrapeptide Antagonist Compounds (TACOs) Based on the Sequence Ac-Xaa1-Arg-(pI)DPhe-Xaa4-NH2

The centrally expressed melanocortin-3 and -4 receptors (MC3R/MC4R) have been studied as possible targets for weight management therapies, with a preponderance of studies focusing on the MC4R. Herein, a novel tetrapeptide scaffold [Ac-Xaa¹-Arg-(pI)DPhe-Xaa⁴-NH₂] is reported. The scaffold was derived from results obtained from a MC3R mixture-based positional scanning campaign. From these results, a set of 48 tetrapeptides were designed and pharmacologically characterized at the mouse melanocortin-1, -3, -4, and -5 receptors. This resulted in the serendipitous discovery of nine compounds that were MC3R agonists (EC₅₀ < 1000 nM) and MC4R antagonists (5.7 < pA₂ < 7.8). The three most potent MC3R agonists, 18 [Ac-Arg-Arg-(pI)DPhe-Tic-NH₂], 1 [Ac-His-Arg-(pI)DPhe-Tic-NH₂], and 41 [Ac-Arg-Arg-(pI)DPhe-DNal(2')-NH₂] were more potent (EC₅₀ < 73 nM) than the melanocortin tetrapeptide Ac-His-DPhe-Arg-Trp-NH₂. This template contains a sequentially reversed "Arg-(pI)DPhe" motif with respect to the classical "Phe-Arg" melanocortin signaling motif, which results in pharmacology that is first-in-class for the central melanocortin receptors.

Direct Phenotypic Screening in Mice: Identification of Individual, Novel Antinociceptive Compounds from a Library of 734,821 Pyrrolidine Bis-piperazines

The hypothesis in the current study is that the simultaneous direct in vivo testing of thousands to millions of systematically arranged mixture-based libraries will facilitate the identification of enhanced individual compounds. Individual compounds identified from such libraries may have increased specificity and decreased side effects early in the discovery phase. Testing began by screening ten diverse scaffolds as single mixtures (ranging from 17,340 to 4,879,681 compounds) for analgesia directly in the mouse tail withdrawal model. The "all X" mixture representing the library TPI-1954 was found to produce significant antinociception and lacked respiratory depression and hyperlocomotor effects using the Comprehensive Laboratory Animal Monitoring System (CLAMS). The TPI-1954 library is a pyrrolidine bis-piperazine and totals 738,192 compounds. This library has 26 functionalities at the first three positions of diversity made up of 28,392 compounds each (26 × 26 × 42) and 42 functionalities at the fourth made up of 19,915 compounds each (26 × 26 × 26). The 120 resulting mixtures representing each of the variable four positions were screened directly in vivo in the mouse 55 °C warm-water tail-withdrawal assay (ip administration). The 120 samples were then ranked in terms of their antinociceptive activity. The synthesis of 54 individual compounds was then carried out. Nine of the individual compounds produced dose-dependent antinociception equivalent to morphine. In practical terms what this means is that one would not expect multiexponential increases in activity as we move from the all-X mixture, to the positional scanning libraries, to the individual compounds. Actually because of the systematic formatting one would typically anticipate steady increases in activity as the complexity of the mixtures is reduced. This is in fact what we see in the current study. One of the final individual compounds identified, TPI 2213-17, lacked significant respiratory depression, locomotor impairment, or sedation. Our results represent an example of this unique approach for screening large mixture-based libraries directly in vivo to rapidly identify individual compounds.

Combinatorial Libraries As a Tool for the Discovery of Novel, Broad-Spectrum Antibacterial Agents Targeting the ESKAPE Pathogens

Mixture based synthetic combinatorial libraries offer a tremendous enhancement for the rate of drug discovery, allowing the activity of millions of compounds to be assessed through the testing of exponentially fewer samples. In this study, we used a scaffold-ranking library to screen 37 different libraries for antibacterial activity against the ESKAPE pathogens. Each library contained between 10000 and 750000 structural analogues for a total of >6 million compounds. From this, we identified a bis-cyclic guanidine library that displayed strong antibacterial activity. A positional scanning library for these compounds was developed and used to identify the most effective functional groups at each variant position. Individual compounds were synthesized that were broadly active against all ESKAPE organisms at concentrations <2 μM. In addition, these compounds were bactericidal, had antibiofilm effects, showed limited potential for the development of resistance, and displayed almost no toxicity when tested against human lung cells and erythrocytes. Using a murine model of peritonitis, we also demonstrate that these agents are highly efficacious in vivo.

Identification of tetrapeptides from a mixture based positional scanning library that can restore nM full agonist function of the L106P, I69T, I102S, A219V, C271Y, and C271R human melanocortin-4 polymorphic receptors (hMC4Rs)

Human obesity has been linked to genetic factors and single nucleotide polymorphisms (SNPs). Melanocortin-4 receptor (MC4R) SNPs have been associated with up to 6% frequency in morbidly obese children and adults. A potential therapy for individuals possessing such genetic modifications is the identification of molecules that can restore proper receptor signaling and function. These compounds could serve as personalized medications improving quality of life issues as well as alleviating diseases symptoms associated with obesity including type 2 diabetes. Several hMC4 SNP receptors have been pharmacologically characterized in vitro to have a decreased, or a lack of response, to endogenous agonists such as α-, β-, and γ2-melanocyte stimulating hormones (MSH) and adrenocorticotropin hormone (ACTH). Herein we report the use of a mixture based positional scanning combinatorial tetrapeptide library to discover molecules with nM full agonist potency and efficacy to the L106P, I69T, I102S, A219V, C271Y, and C271R hMC4Rs. The most potent compounds at all these hMC4R SNPs include Ac-His-(pI)DPhe-Tic-(pNO2)DPhe-NH2, Ac-His-(pCl)DPhe-Tic-(pNO2)DPhe-NH2, Ac-His-(pCl)DPhe-Arg-(pI)Phe-NH2, and Ac-Arg-(pCl)DPhe-Tic-(pNO2)DPhe-NH2, revealing new ligand pharmacophore models for melanocortin receptor drug design strategies.

Conditional probabilistic analysis for prediction of the activity landscape and relative compound activities

Structure-property relationships and structure-activity relationships play an important role in many research areas, such as medicinal chemistry and drug discovery. Such methods, however, have focused on providing post-hoc descriptions of such relationships based on known data. The ability for these descriptions to remain relevant when considering compounds of unknown activity, and thus the prediction of activity and property landscapes using existing data, remains little explored. In this study, we present a novel method of evaluating the ability of a compound comparison methodology to provide accurate information about a set of unknown compounds and also explore the ability of these predicted activity landscapes to prioritize active compounds over inactive. These methods are applied to three distinct and diverse sets of compounds, each with activity data for multiple targets, for a total of eight target-compound set pairs. Six methodologically distinct compound comparison methods were evaluated. We show that overall, all compound comparison methods provided an improvement in structure-activity relationship prediction over random and were able to prioritize compounds in a superior manner to random sampling, but the degree of success and therefore applicability varied markedly.

Selective agonists and antagonists of formylpeptide receptors: duplex flow cytometry and mixture-based positional scanning libraries

The formylpeptide receptor (FPR1) and formylpeptide-like 1 receptor (FPR2) are G protein-coupled receptors that are linked to acute inflammatory responses, malignant glioma stem cell metastasis, and chronic inflammation. Although several N-formyl peptides are known to bind to these receptors, more selective small-molecule, high-affinity ligands are needed for a better understanding of the physiologic roles played by these receptors. High-throughput assays using mixture-based combinatorial libraries represent a unique, highly efficient approach for rapid data acquisition and ligand identification. We report the superiority of this approach in the context of the simultaneous screening of a diverse set of mixture-based small-molecule libraries. We used a single cross-reactive peptide ligand for a duplex flow cytometric screen of FPR1 and FPR2 in color-coded cell lines. Screening 37 different mixture-based combinatorial libraries totaling more than five million small molecules (contained in 5,261 mixture samples) resulted in seven libraries that significantly inhibited activity at the receptors. Using positional scanning deconvolution, selective high-affinity (low nM K(i)) individual compounds were identified from two separate libraries, namely, pyrrolidine bis-diketopiperazine and polyphenyl urea. The most active individual compounds were characterized for their functional activities as agonists or antagonists with the most potent FPR1 agonist and FPR2 antagonist identified to date with an EC₅₀ of 131 nM (4 nM K(i)) and an IC₅₀ of 81 nM (1 nM K(i)), respectively, in intracellular Ca²⁺ response determinations. Comparative analyses of other previous screening approaches clearly illustrate the efficiency of identifying receptor selective, individual compounds from mixture-based combinatorial libraries.

Rapid scanning structure-activity relationships in combinatorial data sets: identification of activity switches

We present a general approach to describe the structure-activity relationships (SAR) of combinatorial data sets with activity for two biological endpoints with emphasis on the rapid identification of substitutions that have a large impact on activity and selectivity. The approach uses dual-activity difference (DAD) maps that represent a visual and quantitative analysis of all pairwise comparisons of one, two, or more substitutions around a molecular template. Scanning the SAR of data sets using DAD maps allows the visual and quantitative identification of activity switches defined as specific substitutions that have an opposite effect on the activity of the compounds against two targets. The approach also rapidly identifies single- and double-target R-cliffs, i.e., compounds where a single or double substitution around the central scaffold dramatically modifies the activity for one or two targets, respectively. The approach introduced in this report can be applied to any analogue series with two biological activity endpoints. To illustrate the approach, we discuss the SAR of 106 pyrrolidine bis-diketopiperazines tested against two formylpeptide receptors obtained from positional scanning deconvolution methods of mixture-based libraries.

A new record of whale shark Rhincodon typus in Brazilian waters: a report of association with Caranx crysos

In May 2011, a Rhincodon typus was sighted on the continental shelf of the central Brazilian coast, in the vicinity of a gas platform. During the video record, an interspecific following association was observed between a Caranx crysos school and the R. typus.

A novel method for the determination of isokinetic ratios and its application in the synthesis of two new positional scanning libraries

A novel method for the direct evaluation of the equimolarity of the compounds contained in a mixture is presented. We applied the method toward calculating isokinetic ratios for the reaction between the amine termini of a resin bound peptide fragment and a sulfonyl chloride to produce equal molar mixtures of sulfonamides. The results of this study and the application of the method to the synthesis of two new positional scanning synthetic combinatorial libraries (PS-SCL) are discussed.

Reef fish structure and distribution in a south-western Atlantic Ocean tropical island

The community structure of the reef fish fauna of Trindade Island, a volcanic oceanic island located 1160 km off the coast of Brazil, is described based on intensive visual censuses. Seventy-six species were encountered in 252 censuses, with mean ± S.E. of 99 ± 3 individuals and 15.7 ± 0.3 species 40 m(-2) transect. The average fish biomass, calculated from length-class estimation, was 22.1 kg 40 m(-2) transect. The species contributing most to biomass were, in decreasing order, Melichthys niger, Cephalopholis fulva, Kyphosus spp., Holocentrus adscensionis, Sparisoma amplum, Sparisoma axillare, Acanthurus bahianus and Epinephelus adscensionis. Carnivorous fishes were the largest trophic group in terms of biomass, followed by omnivores and roving herbivores. The two predominant types of reef habitat, fringing reefs built by coralline algae and rocky reefs made of volcanic boulders, showed significant differences in the biomass and the abundance of the trophic guilds. Within each habitat type, significant differences in species richness, density and biomass were detected among crest, slope and interface zones. Although similar in overall species composition to coastal reefs in Brazil, the fish fauna of Trindade Island shares certain characteristics, such as a high abundance of planktivores, with other Brazilian oceanic islands. Despite comparatively high fish biomass, including the macro-carnivorous species habitually targeted by fisheries, signs of overfishing were evident. These findings highlight the urgency for a conservation initiative for this isolated, unique and vulnerable reef system.

GM-CSF production allows the identification of immunoprevalent antigens recognized by human CD4+ T cells following smallpox vaccination

The threat of bioterrorism with smallpox and the broad use of vaccinia vectors for other vaccines have led to the resurgence in the study of vaccinia immunological memory. The importance of the role of CD4+ T cells in the control of vaccinia infection is well known. However, more CD8+ than CD4+ T cell epitopes recognized by human subjects immunized with vaccinia virus have been reported. This could be, in part, due to the fact that most of the studies that have identified human CD4+ specific protein-derived fragments or peptides have used IFN-γ production to evaluate vaccinia specific T cell responses. Based on these findings, we reasoned that analyzing a large panel of cytokines would permit us to generate a more complete analysis of the CD4 T cell responses. The results presented provide clear evidence that TNF-α is an excellent readout of vaccinia specificity and that other cytokines such as GM-CSF can be used to evaluate the reactivity of CD4+ T cells in response to vaccinia antigens. Furthermore, using these cytokines as readout of vaccinia specificity, we present the identification of novel peptides from immunoprevalent vaccinia proteins recognized by CD4+ T cells derived from smallpox vaccinated human subjects. In conclusion, we describe a “T cell–driven” methodology that can be implemented to determine the specificity of the T cell response upon vaccination or infection. Together, the single pathogen in vitro stimulation, the selection of CD4+ T cells specific to the pathogen by limiting dilution, the evaluation of pathogen specificity by detecting multiple cytokines, and the screening of the clones with synthetic combinatorial libraries, constitutes a novel and valuable approach for the elucidation of human CD4+ T cell specificity in response to large pathogens.

Use and implications of the harmonic mean model on mixtures for basic research and drug discovery

The use of the harmonic mean model for predicting the activities of a given mixture and its constituents has not previously been explored in the context of combinatorial libraries and drug discovery. Herein, the analyses of historical data confirm the harmonic mean as an accurate predictor of mixture activity. The implications of these results are discussed.

Effects of ayahuasca on psychometric measures of anxiety, panic-like and hopelessness in Santo Daime members

The use of the hallucinogenic brew ayahuasca, obtained from infusing the shredded stalk of the malpighiaceous plant Banisteriopsis caapi with the leaves of other plants such as Psychotria viridis, is growing in urban centers of Europe, South and North America in the last several decades. Despite this diffusion, little is known about its effects on emotional states. The present study investigated the effects of ayahuasca on psychometric measures of anxiety, panic-like and hopelessness in members of the Santo Daime, an ayahuasca-using religion. Standard questionnaires were used to evaluate state-anxiety (STAI-state), trait-anxiety (STAI-trait), panic-like (ASI-R) and hopelessness (BHS) in participants that ingested ayahuasca for at least 10 consecutive years. The study was done in the Santo Daime church, where the questionnaires were administered 1h after the ingestion of the brew, in a double-blind, placebo-controlled procedure. While under the acute effects of ayahuasca, participants scored lower on the scales for panic and hopelessness related states. Ayahuasca ingestion did not modify state- or trait-anxiety. The results are discussed in terms of the possible use of ayahuasca in alleviating signs of hopelessness and panic-like related symptoms.

Molecular characterization of a neutralizing murine monoclonal antibody against Tityus serrulatus scorpion venom

Monoclonal antibodies (mAbs) against Tityus serrulatus venom were obtained by the fusion of SP2/0 murine myeloma cells and spleen cells from BALB/c mice immunized with a toxic fraction (TstFG50) of the Tityus venom (this G50 chromatography fraction represents most of the toxicity of the crude venom) conjugated to bovine serum albumin (BSA) with glutaraldehyde. From the initial screening of over 200 hybridoma fusion wells, a panel of 9 anti-TstFG50 secreting hybridomas was established. The capacity of mAbs to neutralize the TstFG50 toxic fraction toxic was determined by in vitro neutralization assays and by inhibition of the binding of 125I-TsVII to its site on rat brain synaptosomes. Only mAbTs1 neutralized 50% of the toxic effects produced by scorpion venom and showed 35% inhibition of the binding of 125I-TsVII at 10(-7) M. To map the epitope recognized by the protective mAbTs1, we prepared a comprehensive series of overlapping 15-mer synthetic peptides covering the amino acid sequences of the four Tityus proteins. MAbTs1 reacted with peptide 26 of TsIV (KKSKDKKADSGYSYW), peptide 30 of TsVII (KKGSSGYSAWPASYS) and peptide 31 of TsNTxP (KKGSSGYSAWPASYS). MAbTs1 was not reactive with any peptide from TsII. The N-terminal lysine residue from the epitope was found to be critical for mAbTs1 binding. The epitope was positioned on the available three-dimensional structure of TsVII together with the recently identified residues from the pharmacophore of beta-scorpion toxins. The neutralizing properties of mAbTs1 might be explained by spatial vicinity of epitope residues with pharmacophore residues.

Fulminant hepatic failure: Wilson's disease or autoimmune hepatitis? Implications for transplantation

Fulminant hepatic failure (FHF) accounts for 10-15% of pediatric liver transplants in the USA annually. Because the onset of FHF may be the first presentation of Wilson's disease (WD) and autoimmune hepatitis (AIH) in previously asymptomatic adolescents, determination of the etiology of FHF is critical as treatment and prognosis differ between these two entities. Patients with AIH may be salvaged by medical treatment. On the contrary, liver transplantation is currently the only life saving therapeutic option available for patients with WD who present with fulminant liver failure. To establish the diagnosis of WD and AIH in the setting of FHF remains challenging for diagnosticians and decisions regarding liver transplantation may be necessary before a diagnosis is firmly established. We report a previously asymptomatic patient who presented with FHF and clinical and laboratory features suggestive of both WD and AIH and who underwent successful therapeutic liver transplantation before the diagnosis of WD could be confirmed.

The relationship between child temperament and early childhood caries

PURPOSE

Among the potential risk factors associated with nursing caries/baby bottle tooth decay--a subset of Early Childhood Caries (ECC)--is a "strong-tempered" behavioral style in the child. However, the few empirical studies that have investigated this description remain controversial. The research goal of this study was to operationalize the "strong-tempered" profile and investigate its association to parental feeding practices and ECC levels.

METHODS

In an observational-correlational study design, 58 children (ASA I), ages 18 to 70 months (M = 43 months, SD = 17), were reliably assessed for ECC levels by a clinical evaluator. A second evaluator, blind to ECC status, interviewed parents using a demographic survey, a feeding practices measure, and the EAS Temperament Survey for Children.

RESULTS

Multiple regression analyses indicated that none of the four temperament factors (Emotionality, Activity, Sociability, and Shyness) significantly predicted duration of feeding habit defined as the length of time in months that the child breast or bottle fed, whichever lasted the longest. However, the combination of greater duration of feeding habit and higher levels of Shyness predicted all three measures of ECC: the presence or absence of caries (r2 = .19, P < .001), the number of carious teeth (r2 = .23, P < .001) and the number of carious surfaces (r2 = .21, P < .001). Furthermore, the addition of Native status significantly increased the predictive value of all of three models (r2 = .37, r2 = .43, r2 = .29, respectively, Ps < .0001).

CONCLUSION

Temperament did not predict the duration of feeding habit but together, shyness and duration of feeding habit was associated with ECC.

Binding sites and actions of Tx1, a neurotoxin from the venom of the spider Phoneutria nigriventer, in guinea pig ileum

Tx1, a neurotoxin isolated from the venom of the South American spider Phoneutria nigriventer, produces tail elevation, behavioral excitation and spastic paralysis of the hind limbs after intracerebroventricular injection in mice. Since Tx1 contracts isolated guinea pig ileum, we have investigated the effect of this toxin on acetylcholine release, as well as its binding to myenteric plexus-longitudinal muscle membranes from the guinea pig ileum. [125I]-Tx1 binds specifically and with high affinity (Kd = 0.36 +/- 0.02 nM) to a single, non-interacting (nH = 1.1), low capacity (Bmax 1.1 pmol/mg protein) binding site. In competition experiments using several compounds (including ion channel ligands), only PhTx2 and PhTx3 competed with [125I]-Tx1 for specific binding sites (K0.5 apparent = 7.50 x 10(-4) g/l and 1.85 x 10(-5) g/l, respectively). PhTx2 and PhTx3, fractions from P. nigriventer venom, contain toxins acting on sodium and calcium channels, respectively. However, the neurotoxin PhTx2-6, one of the isoforms found in the PhTx2 pool, did not affect [125I]-Tx1 binding. Tx1 reduced the [3H]-ACh release evoked by the PhTx2 pool by 33%, but did not affect basal or KCl-induced [3H]-ACh release. Based on these results, as well as on the homology of Tx1 with toxins acting on calcium channels (omega-Aga IA and IB) and its competition with [125I]-omega-Cono GVIA in the central nervous system, we suggest that the target site for Tx1 may be calcium channels.

Temperament and trait anxiety as predictors of child behavior prior to general anesthesia for dental surgery

Children's individual styles of interaction with the environment (temperament) influence stable tendencies towards distress (trait anxiety) and context-specific manifestations of distress (state anxiety). Measures of temperament and trait anxiety were examined as predictors of state anxiety (i.e., disruptive behaviors) in the presurgical setting. During a 2-month period, 51 nonpremedicated, healthy children (M = 3 years of age) were consecutively studied-as they presented to a hospital setting for dental treatment under general anesthesia (GA). Using correlation and backward multiple regression analyses, one temperament category (shyness), but not trait anxiety (the revised CMAS), predicted disruptive behaviors (the revised MBPRS) during preseparation (r2 = .16, P = .0038) and separation (r2 = .09, P = .0281) from parents. Shyness, age, and gender best predicted disruptive behaviors during preseparation (multiple R2 = .31, P = .0005). Temperament (a) predicts children's distress in the presurgical setting, and (b) appears to be moderated by age, gender, and interpersonal factors. Awareness of temperamental influences can help predict children's behavior and aid in the presurgical care of children.

[The porcine valve prosthesis and pregnancy]

Anticoagulation is the chief problem during pregnancy of women with mechanical prosthetic valves. Many studies have investigated a nonthrombogenic valve. Since 1978 we have used a biological porcine prosthetic valves in 16 pregnancies, 11 patients with regular clinical electrocardiographic, echocardiographic and chest roentgenographic follow-up. The patients' ages were 19 to 32 years during pregnancy. Nine had mitral, one aortic and one mitro-aortic prosthesis. Two patients dropped out during the study so we completed it with 14 pregnancies. Six patients coursed with grade I heart failure (HYHA), five grade II and three grade IV. All of them were treated clinically. Four valves had dysfunction and calcification during pregnancy and two before pregnancy. The pregnancies resulted in three abortions, seven normal deliveries and four caesarean section with obstetric indication. Fetal distress was not observed during or after delivery. The physiopathology of valve dysfunction during pregnancy was discussed and it was concluded that the biologic porcine prosthetic valve allows hemodynamic stabilization. If dysfunction appears it may be clinically controlled without need of anticoagulation, risk of calcification nor dysfunction during pregnancy. The biologic valves are best indicated for women who wish to become pregnant after valve substitution.