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The 16th GCC Closed Forum was held in Orlando, FL, USA, on 23 June 2023. Representatives from international bioanalytical Contract Research Organizations were in attendance in order to discuss scientific and regulatory issues specific to bioanalysis. The issues discussed at the meeting included: IS response, flow cytometry, changes to the bioanalytical industry, NGS assays, biomarker assay for tissues, dPCR validation, immunogenicity harmonization and ICH M10 implementation. Conclusions and consensus from discussions of these topics are included in this article.

The 12th GCC Closed Forum was held in Philadelphia, PA, USA, on 9 April 2018. Representatives from international bioanalytical Contract Research Organizations were in attendance in order to discuss scientific and regulatory issues specific to bioanalysis. The issues discussed at the meeting included: critical reagents; oligonucleotides; certificates of analysis; method transfer; high resolution mass spectrometry; flow cytometry; recent regulatory findings and case studies involving stability and nonclinical immunogenicity. Conclusions and consensus from discussions of these topics are included in this article.

The effects of femtosecond laser ablation on the physical and chemical properties at the surface of poly methylmethacrylate (PMMA) were studied. Femtosecond laser microfabrication caused the initially wetting behavior of PMMA to become nonwetting, mainly because of the laser-induced surface porosity at the submicroscale. Static and dynamic contact angle measurements along with morphological characterization revealed that after the laser irradiation, the system lies in an intermediate regime between those theorized by Wenzel and Cassie-Baxter. Spectroscopic analysis did not evidence any significant variation in the chemical properties of the processed polymeric surfaces.

Heme oxygenase 1 (HO-1) is an enzyme important in the catabolism of heme that is induced under conditions of oxidative stress. HO-1 degradation of heme yields biliverdin, bilirubin, carbon monoxide and iron. HO-1 is thought to serve a protective antioxidant function, and upregulation of HO-1 has been demonstrated in experimental models of neurodegeneration, subarachnoid hemorrhage, cerebral ischemia and traumatic brain injury (TBI). We measured HO-1 concentration in cerebral spinal fluid samples from 48 infants and children following TBI and 7 control patients by ELISA. Increased HO-1 was seen in TBI versus control patients--mean 2.75+/-0.63, peak 4.17+/-0.96 ng/ml versus control (<0.078 ng/ml, not detectable) (p<0.001). Increased HO-1 concentration was associated with increased injury severity and unfavorable neurological outcome (both p<0.05). Increased HO-1 concentration was independently associated with younger age; however, statistical analysis could not rule out the possibility that the effect of age was related to inflicted TBI from child abuse. HO-1 increases after TBI and appears to be more prominent in infants compared with older children after injury., (Copyright (c) 2006 S. Karger AG, Basel.)

The American Heart Association has endorsed the use of mild hypothermia for adults after cardiopulmonary arrest. However, there are no contemporary trials testing hypothermia in children after cardiopulmonary arrest and extrapolation from adult studies is problematic given differences in brain development and primary etiology (asphyxia in children vs. ventricular arrhythmia in adults). Accordingly, we tested the effects of mild postresuscitative hypothermia on functional and histopathological outcome after asphyxial cardiac arrest in juvenile rats. Postnatal day 17 rats were subjected to 8 min of asphyxia-induced cardiac arrest followed by resuscitation. Rats were randomized to normothermic (37 degrees C), hypothermic (32 degrees C), or unregulated temperature groups (n = 7-8/group) to begin after return of spontaneous circulation for a duration of 1 h. Brain temperature in the unregulated group dropped to 34.0 +/- 0.4 degrees C at 1 h. The hypothermic group had improved motor function assessed using beam balance and inclined plane tests vs. the normothermic group. The depth of hypothermia was associated with increased CA1 hippocampal neuron survival at 5 weeks. Neurodegeneration in the CA1 hippocampus assessed using Fluoro-Jade B labeling at 5 weeks was not detected in the 32 degrees C group, whereas 2/7 and 4/7 rats in the 34 and 37 degrees C groups, respectively, showed neurodegeneration. Brief treatment with moderate induced hypothermia improved functional outcome and prevented long-term neurodegeneration in a model that mimics the clinical and histopathological scenario of pediatric cardiac arrest. Similar to adults, infants and children may benefit from induced hypothermia after cardiopulmonary arrest, warranting further study.

Objective: Develop a clinically relevant model of pediatric asphyxial cardiopulmonary arrest in rats., Design: Prospective interventional study., Setting: University research laboratory., Subjects: Postnatal day 16-18 rats (n = 9/group)., Interventions: Anesthetized rats were endotracheally intubated and mechanically ventilated, and vascular catheters were inserted. Vecuronium was administered, and the ventilator was disconnected from the rats for 8 mins, whereupon rats were resuscitated with epinephrine, sodium bicarbonate, and chest compressions until spontaneous circulation returned. Shams underwent all procedures except asphyxia., Measurements and Main Results: Asphyxial arrest typically occurred by 1 min after the ventilator was disconnected. Return of spontaneous circulation typically occurred <30 secs after resuscitation. An isoelectric electroencephalograph was observed for 30 mins after asphyxia, and rats remained comatose for 12-24 hrs. Overall survival rate was 85%. Motor function measured using beam balance and inclined plane tests was impaired on days 1 and 2, but recovered by day 3, in rats after asphyxia vs. sham injury (p <.05). Spatial memory acquisition measured using the Morris-water maze on days 7-14 and 28-35 was also impaired in rats after asphyxia vs. sham injury (total latency 379 +/- 28 vs. 501 +/- 40 secs, respectively, p <.05). DNA fragmentation was detected in CA1 hippocampal neurons bilaterally 3-7 days after asphyxia. Neurodegeneration detected using Fluorojade B was seen in bilateral CA1 hippocampi and layer V cortical neurons 3-7 days after asphyxia, with persistent neurodegeneration in CA1 hippocampus detected up to 5 wks after asphyxia. CA1 hippocampal neuron survival after asphyxia was 39-43% (p <.001 vs. sham). Evidence of DNA or cellular injury was not detected in sham rats., Conclusions: This model of asphyxial cardiopulmonary arrest in postnatal day 17 rats produces many of the clinical manifestations of pediatric hypoxic-ischemic encephalopathy. This model may be useful for the preclinical testing of novel and currently available interventions aimed at improving neurologic outcome in infants and children after cardiopulmonary arrest.