[Phototherapeutic keratectomy for epithelial basement membrane dystrophy : Impact of excimer laser systems used on the changes of visual acuity, refraction and astigmatism]. / Phototherapeutische Keratektomie bei Epithel-Basalmembran-Dystrophie : Einfluss verwendeter Excimerlaser-Systeme auf die Entwicklung von Visus, Refraktion und Astigmatismus.

BACKGROUND: Excimer laser-assisted phototherapeutic keratectomy (PTK) has become established as the gold standard in treatment of epithelial basement membrane dystrophy (EBMD), commonly also known as map-dot-fingerprint dystrophy (MDF). At the Department of Ophthalmology, Saarland University Medical Center in Homburg/Saar, systems from Zeiss Meditec and Schwind have been used. The outcomes of both were compared in this study. PATIENTS AND METHODS: The retrospective study included patients who underwent PTK with a diagnosis of MDF between 2007 and 2017. A total of 170 operations were performed using Zeiss Meditec MEL-70 (Carl Zeiss Meditec AG, Jena, Germany) and 98 using a Schwind eye-tech-solutions Amaris 750S laser (Schwind eye-tech-solutions GmbH, Kleinostheim, Germany). Preoperative and postoperative data for visual acuity, refraction and astigmatism as well as curvature data from the Pentacam and endothelial cell count were collected. The follow-up period averaged 8 months. RESULTS: In both groups visual acuity postoperatively was significantly better (Zeiss: p < 0.001, Schwind p < 0.004). The improvement in the Schwind group was less than in the Zeiss group, which is the reason why there was a significant difference between the laser systems postoperatively (p < 0.017). There were no significant changes regarding the spherical equivalent after PTK. Regarding astigmatism, there was a significant decrease in the Zeiss group (p < 0.042), while it did not change significantly in patients treated with Schwind laser (p < 0.217). Overall, this led to a significant postoperative difference between both laser systems (p < 0.014). CONCLUSION: The PTK can be recommended as an effective treatment method for patients with EBMD, regardless of the laser systems used. Patients benefit from long relief from recurrences with improved or constant visual acuity and stable refraction.

Pharmacokinetic and pharmacodynamic properties of aerosolized ("vaped") THC in adolescent male and female rats.

RATIONALE: Adolescent exposure to ∆9-tetrahydrocannabinol (THC), the psychotropic constituent of cannabis, might affect brain development, and in rodent models leads to long-term behavioral and physiological alterations. Yet, the basic pharmacology of this drug in adolescent rodents, especially when ingested via ecologically relevant routes like aerosol inhalation, commonly referred to as "vaping," is still poorly characterized. Moreover, sex differences exist in THC metabolism, kinetics, and behavioral effects, but these have not been rigorously examined after vapor dosing in adolescents. OBJECTIVES: We investigated the pharmacokinetics and pharmacodynamics of aerosolized THC (30 min inhalation exposure, 25 or 100 mg/ml) in adolescent Wistar rats of both sexes. METHODS: Liquid chromatography/mass spectrometry analysis of THC and its major metabolites was conducted on blood plasma and brain tissue at 5, 30, 60, and 120 min following a 30-min aerosol dosing session. Effects on activity in a novel environment for 120 min after aerosol, and temperature, were measured in separate rats. RESULTS: We found sex-dependent differences in the pharmacokinetics of THC and its active (11-OH-THC) and inactive (11-COOH-THC) metabolites in the blood and brain, along with dose- and sex-dependent effects on anxiety-like and exploratory behaviors; namely, greater 11-OH-THC levels accompanied by greater behavioral effects in females at the low dose but similar hypothermic effects in both sexes at the high dose. CONCLUSIONS: These results provide a benchmark for dosing adolescent rats with aerosolized (or "vaped") THC, which could facilitate adoption by other labs of this potentially human-relevant THC exposure model to understand cannabis effects on the developing brain.

The ethical dilemma of emergency department patients with low-risk chest pain.

Millions of patients present to US EDs each year with symptoms concerning for acute coronary syndrome (ACS), but fewer than 10% are ultimately diagnosed with ACS. Well-tested and externally validated accelerated diagnostic protocols were developed to aid providers in risk stratifying patients with possible ACS and have become central components of current ED practice guidelines. Nevertheless, the fear of missing ACS continues to be a strong motivator for ED providers to pursue further testing for their patients. An ethical dilemma arises when the provider must balance the risk of ACS if the patient is discharged compared with the potential harms caused by a cardiac workup. Providers should be familiar with the ethical principles relevant to this dilemma in order to determine what is in the best interests of the patient.

Adolescent cannabinoid exposure effects on natural reward seeking and learning in rats.

RATIONALE: Adolescence is characterized by endocannabinoid (ECB)-dependent refinement of neural circuits underlying emotion, learning, and motivation. As a result, adolescent cannabinoid receptor stimulation (ACRS) with phytocannabinoids or synthetic agonists like "Spice" cause robust and persistent changes in both behavior and circuit architecture in rodents, including in reward-related regions like medial prefrontal cortex and nucleus accumbens (NAc). OBJECTIVES AND METHODS: Here, we examine persistent effects of ACRS with the cannabinoid receptor 1/2 specific agonist WIN55-212,2 (WIN; 1.2 mg/kg/day, postnatal day (PD) 30-43), on natural reward-seeking behaviors and ECB system function in adult male Long Evans rats (PD 60+). RESULTS: WIN ACRS increased palatable food intake, and altered attribution of incentive salience to food cues in a sign-/goal-tracking paradigm. ACRS also blunted hunger-induced sucrose intake, and resulted in increased anandamide and oleoylethanolamide levels in NAc after acute food restriction not seen in controls. ACRS did not affect food neophobia or locomotor response to a novel environment, but did increase preference for exploring a novel environment. CONCLUSIONS: These results demonstrate that ACRS causes long-term increases in natural reward-seeking behaviors and ECB system function that persist into adulthood, potentially increasing liability to excessive natural reward seeking later in life.

Immunosuppressive human anti-CD83 monoclonal antibody depletion of activated dendritic cells in transplantation.

Current immunosuppressive/anti-inflammatory agents target the responding effector arm of the immune response and their nonspecific action increases the risk of infection and malignancy. These effects impact on their use in allogeneic haematopoietic cell transplantation and other forms of transplantation. Interventions that target activated dendritic cells (DCs) have the potential to suppress the induction of undesired immune responses (for example, graft versus host disease (GVHD) or transplant rejection) and to leave protective T-cell immune responses intact (for example, cytomegalovirus (CMV) immunity). We developed a human IgG1 monoclonal antibody (mAb), 3C12, specific for CD83, which is expressed on activated but not resting DC. The 3C12 mAb and an affinity improved version, 3C12C, depleted CD83(+) cells by CD16(+) NK cell-mediated antibody-dependent cellular cytotoxicity, and inhibited allogeneic T-cell proliferation in vitro. A single dose of 3C12C prevented human peripheral blood mononuclear cell-induced acute GVHD in SCID mouse recipients. The mAb 3C12C depleted CMRF-44(+)CD83(bright) activated DC but spared CD83(dim/-) DC in vivo. It reduced human T-cell activation in vivo and maintained the proportion of CD4(+) FoxP3(+) CD25(+) Treg cells and also viral-specific CD8(+) T cells. The anti-CD83 mAb, 3C12C, merits further evaluation as a new immunosuppressive agent in transplantation.

Exploring the Role of Residue 228 in Substrate and Inhibitor Recognition by VIM Metallo-ß-lactamases.

ß-Lactamase inhibitors (BLIs) restore the efficacy of otherwise obsolete ß-lactams. However, commercially available BLIs are not effective against metallo-ß-lactamases (MBLs), which continue to be disseminated globally. One group of the most clinically important MBLs is the VIM family. The discovery of VIM-24, a natural variant of VIM-2, possessing an R228L substitution and a novel phenotype, compelled us to explore the role of this position and its effects on substrate specificity. We employed mutagenesis, biochemical and biophysical assays, and crystallography. VIM-24 (R228L) confers enhanced resistance to cephems and increases the rate of turnover compared to that of VIM-2 (kcat/KM increased by 6- and 10-fold for ceftazidime and cefepime, respectively). Likely the R → L substitution relieves steric clashes and accommodates the C3N-methyl pyrrolidine group of cephems. Four novel bisthiazolidine (BTZ) inhibitors were next synthesized and tested against these MBLs. These inhibitors inactivated VIM-2 and VIM-24 equally well (Ki* values of 40-640 nM) through a two-step process in which an initial enzyme (E)-inhibitor (I) complex (EI) undergoes a conformational transition to a more stable species, E*I. As both VIM-2 and VIM-24 were inhibited in a similar manner, the crystal structure of a VIM-2-BTZ complex was determined at 1.25 Å and revealed interactions of the inhibitor thiol with the VIM Zn center. Most importantly, BTZs also restored the activity of imipenem against Klebsiella pneumoniae and Pseudomonas aeruginosa in whole cell assays producing VIM-24 and VIM-2, respectively. Our results suggest a role for position 228 in defining the substrate specificity of VIM MBLs and show that BTZ inhibitors are not affected by the R228L substitution.

Synthesis of selenazoles by in situ cycloisomerization of propargyl selenoamides using oxygen-selenium exchange reaction.

Herein, we describe an approach toward selenazole preparation based on the cycloisomerization of propargyl selenoamides. The selenoamides were synthesized in situ using the Ishihara reagent with spontaneous cyclization to form the 2,5-disubstituted selenazoles. Heterocylcles 9a-j were prepared using readily available starting materials, and yields ranged from moderate to good (20-80%). Methylselenazole 9a could be transformed into a bromomethyl derivative 13 using NBS. The intermediate 13 would provide a more versatile building block for further derivatizations, e.g., the cyanide 14.

Discovering Echinococcus granulosus thioredoxin glutathione reductase inhibitors through site-specific dynamic combinatorial chemistry.

In this study, we report a strategy using dynamic combinatorial chemistry for targeting the thioredoxin (Trx)-reductase catalytic site on Trx glutathione reductase (TGR), a pyridine nucleotide thiol-disulfide oxido-reductase. We chose Echinococcus granulosus TGR since it is a bottleneck enzyme of platyhelminth parasites and a validated pharmacological target. A dynamic combinatorial library (DCL) was constructed based on thiol-disulfide reversible exchange. We demonstrate the use of 5-thio-2-nitrobenzoic acid (TNB) as a non-covalent anchor fragment in a DCL templated by E. granulosus TGR. The heterodimer of TNB and bisthiazolidine (2af) was identified, upon library analysis by HPLC (IC50 = 24 µM). Furthermore, 14 analogs were synthetically prepared and evaluated against TGR. This allowed the study of a structure-activity relationship and the identification of a disulfide TNB-tricyclic bisthiazolidine (2aj) as the best enzyme inhibitor in these series, with an IC50 = 24 µM. Thus, our results validate the use of DCL for targeting thiol-disulfide oxido-reductases.

Synthesis of 2-hydrazolyl-4-thiazolidinones based on multicomponent reactions and biological evaluation against Trypanosoma Cruzi.

A series of 18 novel 2-hydrazolyl-4-thiazolidinones-5-carboxylic acids, amides and 5,6-α,ß-unsaturated esters were synthesized, and their in vitro activity on cruzipain and T. cruzi epimastigotes was determined. Some agents show activity at 37 µm concentration in the enzyme assay. Computational tools and docking were used to correlate the biological response with the physicochemical parameters of the compounds and their cruzipain inhibitory effects.

Microwave assisted tandem reactions for the synthesis of 2-hydrazolyl-4-thiazolidinones.

A tandem method for the synthesis of 2-hydrazolyl-4-thiazolidinones (5) from commercially available materials in a 3 component reaction has been developed. The reaction connects aldehydes, thiosemicarbazides and maleic anhydride, effectively assisted by microwave irradiation. The synthesis of a new type of compound, 2-hydrazolyl-5,5-diphenyl-4-thiazolidinone (7), obtained by treatment of thiosemicarbazone with benzil in basic media is also reported. HOMO/LUMO energies, orbital coefficients and charge distribution were used to explain the proposed reaction mechanism.

Evidence of heterogeneity in the antibody response against the platelet antigen 3a; recognition of an 11-mer peptide carrying the HPA-3a polymorphic determinant.

BACKGROUND: The immune processes involved in the development of alloantibodies against the human platelet antigens in alloimmune disorders remain unclear. Antibody recognition of the platelet antigens on their respective platelet glycoproteins has been shown to be dependent on glycoprotein conformation. Furthermore, the post-translational modification of glycoproteins adds complexity to the alloantigenic determinants. METHODS: Nine anti-HPA-3a sera along with several control sera were tested for reactivity to an 11-mer peptide straddling the HPA-3a/b polymorphism. Sera found to specifically recognize the 3a peptide were further assessed by platelet pre-exposure and immunoblotting. RESULTS: Three of the nine antisera were found to specifically recognize an 11-mer synthetic 3a peptide by ELISA. Further analysis of all anti-HPA-3a sera by Western blot showed that only those reactive to the 3a peptide were able to bind both reduced and non-reduced GPIIb. CONCLUSION: The results presented in this study provide the first known evidence for the identification of an antibody population capable of recognizing a linear and non-glycosylated form of the HPA-3a epitope.

Practical blood dendritic cell vaccination for immunotherapy of multiple myeloma.

Therapeutic vaccination combined with new drugs may cure multiple myeloma (MM). We have developed a bio-process to purify CMRF-56 monoclonal antibody (mAb) and a standard operating procedure to immunoselect blood dendritic cells (BDC). Leucopheresed mononuclear cells were cultured overnight, labelled with CMRF-56 mAb and BDC prepared using a clinical scale immunoselection system. The mean BDC yield from healthy donors was 48% (n = 6, purity 28%). Preparations from MM patients (n = 6, yield 47%, purity 35%) primed cytotoxic T lymphocytes (CTL) to clinically relevant MM antigens. This procedure can be performed readily by clinical cell manufacturing units to facilitate BDC vaccination studies.

Surgical resection of a primary tracheal fibrosarcoma in a dog.

A four-year-old, entire male Rottweiler was presented with a history of respiratory distress. A tracheal mass was diagnosed on thoracic radiographs and tracheoscopy. Surgical excision of three tracheal rings incorporating the tumour was performed. The mass was found to be a low-grade fibrosarcoma. Twenty-four months later, the owner reported that there was no recurrence of respiratory distress and the dog appeared to be doing well clinically. This case of primary tracheal fibrosarcoma suggests that this type of tumour should be listed in the differential diagnoses for tracheal neoplasia in dogs and that surgical treatment alone may be curative.

Surgical resection of a primary tracheal fibrosarcoma in a dog

A four-year-old, entire male Rottweiler was presented with a history of respiratory distress. A tracheal mass was diagnosed on thoracic radiographs and tracheoscopy. Surgical excision of three tracheal rings incorporating the tumour was performed. The mass was found to be a low-grade fibrosarcoma. Twenty-four months later, the owner reported that there was no recurrence of respiratory distress and the dog appeared to be doing well clinically. This case of primary tracheal fibrosarcoma suggests that this type of tumour should be listed in the differential diagnoses for tracheal neoplasia in dogs and that surgical treatment alone may be curative.

Metathesis reactions of pyrazolotriazinones generate dynamic combinatorial libraries.

[reaction: see text] Reversible metathesis reactions of pyrazolotriazinones and aliphatic aldehydes or ketones proceed in aqueous, phosphate-buffered media at pH 4 and 40-60 degrees C to generate thermodynamically controlled mixtures of heterocycles.

Effects of epoetin alfa on blood transfusions and postoperative recovery in orthopaedic surgery: the European Epoetin Alfa Surgery Trial (EEST).

BACKGROUND AND OBJECTIVE: Preoperative epoetin alfa administration decreases transfusion requirements and may reduce transfusion complications, such as postoperative infection due to immune suppression and thus hospitalization time. This study examined the impact of preoperative epoetin alfa administration on postoperative recovery and infection rate. METHODS: In an open randomized controlled multicentre trial in patients undergoing orthopaedic surgery, the effects of preoperative administration of epoetin alfa vs. routine care were compared in six countries. Haemoglobin (Hb) values, transfusions, time to ambulation, time to discharge, infections and safety were evaluated in patients with preoperative Hb concentrations 10-13g dL(-1) (on-treatment population: epoetin n = 460; control n = 235), from study entry until 4-6 weeks after surgery. Outcome was also compared in patients with and without transfusion. RESULTS: Epoetin-treated patients had higher Hb values from the day of surgery until discharge (P < 0.001) and lower transfusion rates (12% vs. 46%; P < 0.001). Epoetin treatment delivered no significant effect on postoperative recovery (time to ambulation, time to discharge and infection rate). However, the time to ambulation (3.8+/-4.0 vs. 3.1+/-2.2days; P < 0.001)and the time to discharge (12.9+/-6.4 vs. 10.2+/-5.0 days; P < 0.001) was longer in the transfused than in the non-transfused patients. Side-effects in both groups were comparable. CONCLUSIONS: Epoetin alfa increases perioperative Hb concentration in mild-to-moderately anaemic patients and thus reduces transfusion requirements. Patients receiving blood transfusions require a longer hospitalization than non-transfused patients.

Effects of haloperidol on reactions to smoking cues in humans.

Both preclinical and clinical evidence suggest that brain dopamine (DA) systems are involved in conditioned responses to drug cues. In smokers, such responses to smoking cues include the subjective urge to smoke and increases in heart rate and reaction time. This study investigated the role of DA in cues associated with smoking and nicotine in cigarette smokers, by acutely pretreating subjects with a DA receptor antagonist. Twenty temporarily abstinent smokers participated in three sessions in which they received haloperidol (HAL; 2 and 4 mg) or placebo before presentations of visual and tactile stimuli related to smoking. HAL (2 mg) attenuated heart rate increases induced by smoking cues, but did not change subjective ratings of smoking urge. HAL (4 mg) also failed to reduce urge to smoke ratings, and did not significantly reduce other cue reactions. These results provide preliminary evidence that acute administration of a low-dose DA antagonist can attenuate some conditioned responses to smoking cues, but not cue-induced urge to smoke.

Increase in synthesis of human monoclonal antibodies by transfected Sp2/0 myeloma mouse cell line under conditions of microgravity.

Microgravity can influence cell growth and function. A transfected Sp2/0 myeloma cell line P3A2 producing a human IgG1 anti-TNFa monoclonal antibody was cultivated in static culture, spinner flasks and simulated microgravity using a rotating wall vessel bioreactor. Microgravity significantly decreased cell growth (from 1.7 x 10(6) to 7.9 x 10(5) cells/ml), but facilitated the synthesis of antibodies, (1.8, 1.3 and 0.5 microg of anti-TNFalpha hmAb per 10(6) viable cells for cells cultivated under microgravity, in spinner flasks and static cultures, respectively). The results suggest that microgravity could be applied to improve the specific productivity of cell lines producing potentially important therapeutic proteins.