Review of Restricted Experiment Requests, Division of Select Agents and Toxins, US Centers for Disease Control and Prevention, 2014-2021

The US Centers for Disease Control and Prevention Division of Select Agents and Toxins (DSAT) regulates laboratories that possess, use, or transfer select agents and toxins within United States as part of the Federal Select Agent Program. DSAT also mitigates biosafety risks through the review of "restricted experiments," which under the select agent regulations are experiments that pose heightened biosafety risks. In a previous study, we evaluated restricted experimental requests submitted to DSAT for review between 2006 and 2013. The purpose of this study is to provide an updated analysis of requests to conduct potential restricted experiments submitted to DSAT between 2014 and 2021. This article describes the trends and characteristics of the data associated with restricted experimental requests involving select agents and toxins that have an impact on public health and safety (US Department of Health and Human Services agents only) or both public health and safety and animal health or products (overlap agents). From January 2014 to December 2021, DSAT received 113 requests to conduct potential restricted experiments; however, 82% (n=93) of those requests were determined not to meet the regulatory definition of a restricted experiment. Of the 20 requests that met the definition of a restricted experiment, 8 were denied because the experiments had the potential to compromise disease control in humans. DSAT continues to encourage entities to practice due diligence and request a review of research that could potentially meet the regulatory definition of a restricted experiment out of an abundance of caution to protect public health and safety and prevent any potential compliance action.

Diagnosis of traumatic brain injury using miRNA signatures in nanomagnetically isolated brain-derived extracellular vesicles

The accurate diagnosis and clinical management of traumatic brain injury (TBI) is currently limited by the lack of accessible molecular biomarkers that reflect the pathophysiology of this heterogeneous disease. To address this challenge, we developed a microchip diagnostic that can characterize TBI more comprehensively using the RNA found in brain-derived extracellular vesicles (EVs). Our approach measures a panel of EV miRNAs, processed with machine learning algorithms to capture the state of the injured and recovering brain. Our diagnostic combines surface marker-specific nanomagnetic isolation of brain-derived EVs, biomarker discovery using RNA sequencing, and machine learning processing of the EV miRNA cargo to minimally invasively measure the state of TBI. We achieved an accuracy of 99% identifying the signature of injured vs. sham control mice using an independent blinded test set (N = 77), where the injured group consists of heterogeneous populations (injury intensity, elapsed time since injury) to model the variability present in clinical samples. Moreover, we successfully predicted the intensity of the injury, the elapsed time since injury, and the presence of a prior injury using independent blinded test sets (N = 82). We demonstrated the translatability in a blinded test set by identifying TBI patients from healthy controls (AUC = 0.9, N = 60). This approach, which can detect signatures of injury that persist across a variety of injury types and individual responses to injury, more accurately reflects the heterogeneity of human TBI injury and recovery than conventional diagnostics, opening new opportunities to improve treatment of traumatic brain injuries.

Review of Requests to Exclude Attenuated Strains of Select Agents and Modified Select Toxins, Division of Select Agents and Toxins, Centers for Disease Control and Prevention, 2003-2017

The Centers for Disease Control and Prevention's Division of Select Agents and Toxins (DSAT) regulates the possession, use, and transfer of select agents and toxins throughout the United States as part of the Federal Select Agent Program. The Department of Health and Human Services (HHS) select agent regulations also include criteria for the exclusion of select agents and toxins from the requirements of the regulations (42 CFR § 73.3 and 73.4). An entity may request the exclusion of an attenuated strain of a select agent or a select toxin modified to be less potent or toxic. The Intragovernmental Select Agents and Toxins Technical Advisory Committee (ISATTAC) reviews the exclusion request by conducting a risk assessment to determine whether the attenuated strain or modified toxin has the potential to pose a severe risk to public health and safety. In this study, DSAT analyzed the number and types of exclusion requests reviewed by the ISATTAC from January 2003 through December 2017. As of December 2017, DSAT has excluded 50 strains of biological agents and 10 modified toxins from the select agent regulations. The select agent regulations provision for the exclusion of attenuated select agents or modified toxins that no longer have the potential to pose a severe threat to public health and safety is an important mechanism for reducing the regulatory burden on entities that do not need to work with the fully virulent or toxic forms of the agent or toxin. This provision may have the added benefit of encouraging entities to consider working with variants of select agents or toxins that are of less risk than the fully virulent or toxic forms in their research studies and as a positive control.

The Value of PIC Cystography in Detecting De Novo and Residual Vesicoureteral Reflux after Dextranomer/Hyaluronic Acid Copolymer Injection

The endoscopic injection of Dx/HA in the management of vesicoureteral reflux (VUR) has become an accepted alternative to open surgery. In the current study we evaluated the value of cystography to detect de novo contralateral VUR in unilateral cases of VUR at the time of Dx/HA injection and correlated the findings of immediate post-Dx/HA injection cystography during the same anesthesia to 2-month postoperative VCUG to evaluate its ability to predict successful surgical outcomes. The current study aimed to evaluate whether an intraoperatively performed cystogram could replace postoperative studies. But a negative intraoperative cystogram correlates with the postoperative study in only 80%. Considering the 75-80% success rate of Dx/HA implantation, the addition of intraoperative cystograms cannot replace postoperative studies. In patients treated with unilateral VUR, PIC cystography can detect occult VUR and prevent postoperative contralateral new onset of VUR.

Prevention of migraine during prodrome with naratriptan

OBJECTIVE

To determine the role of naratriptan in preventing migraine headache when administered during prodrome.

PROCEDURES

Baseline phase: patients recorded prodrome symptoms and time of onset, time when patient knew that headache was inevitable, time of onset and severity of headache. Treatment phase: patients given naratriptan 2.5 mg to take at the time they knew headache was inevitable. Patients recorded prodrome symptoms and time of onset, time they knew headache was inevitable, time naratriptan administered, time of onset and severity of any headache. Patients treated three prodromes separated by at least 48 h.

FINDINGS

Twenty patients completed both phases. During baseline phase, 59 prodromes were reported and all were followed by headache. Severity of headache: 5% mild, 51% moderate, 44% severe. During treatment phase, 63 prodromes were reported. Of these, 38/63 (60%) were not followed by headache. Among headaches that occurred, the majority occurred within 2 h of naratriptan administration, suggesting that naratriptan is more effective in preventing headache if taken early in prodrome. Severity of 25 headaches: 44% mild, 24% moderate, 32% severe.

CONCLUSIONS

Naratriptan 2.5 mg appears to prevent migraine headache when given early in prodrome. If headache occurs, severity appears to be reduced.

alpha-Crystallin protein cognates in eggs of the moth, Plodia interpunctella: possible chaperones for the follicular epithelium yolk protein

alpha-Crystallin protein cognates were found in germ cells of the Indianmeal moth, Plodia interpunctella (Shirk and Zimowska, 1997). A cDNA clone of 674 bp with a single open reading frame was isolated for a 25,000 molecular weight polypeptide member of this family, alpha CP25, and a single transcript of approximately 700 bp was found in the ovary of vitellogenic females. Both the DNA sequence and predicted amino acid sequence showed considerable homology with the embryonic lethal gene, l(2)efl, in Drosophila melanogaster. In addition to the sequence for l(2)efl, the predicted amino acid sequence for acp25 also showed significant sequence similarly with the alpha-crystallin A chain polypeptides from the lenses of vertebrae eyes. An N-terminal hydrophobic aggregation site and a C-terminal protective binding site common to alpha-crystallin proteins were present in the predicted acp25 and l(2)efl amino acid sequences, while only the C-terminal protective binding site was present in the small heat shock protein sequences from D. melanogaster. This evidence suggests that although the alpha-crystallin protein cognates in P. interpunctella evolved from a gene common with small heat shock protein genes, the amino acid sequence has converged on a structure similar to that of alpha-crystallin proteins. Native immunoblot analysis showed that the alpha-crystallin proteins formed high molecular weight complexes with the follicular epithelium yolk protein (FEYP) but not vitellin in yolk. An electroblot binding assay was used to show that the germ-cell alpha-crystallins of P. interpunctella bind specifically with the FEYP and that the binding was reversible in the presence of ATP or low pH. This evidence in conjunction with the evidence that the alpha-crystallins and FEYP form a stable complex that co-purifies from native egg proteins suggests that the alpha-cystallin cognates function as chaperones for the follicular epithelium yolk proteins in the embryos of P. interpunctella.

Characterization of an avian influenza A (H5N1) virus isolated from a child with a fatal respiratory illness

An avian H5N1 influenza A virus (A/Hong Kong/156/97) was isolated from a tracheal aspirate obtained from a 3-year-old child in Hong Kong with a fatal illness consistent with influenza. Serologic analysis indicated the presence of an H5 hemagglutinin. All eight RNA segments were derived from an avian influenza A virus. The hemagglutinin contained multiple basic amino acids adjacent to the cleavage site, a feature characteristic of highly pathogenic avian influenza A viruses. The virus caused 87.5 to 100 percent mortality in experimentally inoculated White Plymouth Rock and White Leghorn chickens. These results may have implications for global influenza surveillance and planning for pandemic influenza.

A note on adults' color-emotion associations

The color-emotion associations of undergraduate students were analyzed. Twenty men and 20 women were asked to complete a self-administered questionnaire in which they listed their favorite color, the major color they were wearing, their emotional responses to colors, and the reasons for their choices. Responses showed that bright colors elicited mainly positive emotional associations, and dark colors elicited mainly negative emotional associations. Women responded more positively than men to bright colors, and they also responded more negatively to dark colors. Comparisons are made between the color-emotion associations of children and those of adults. The reasons for the color-emotion associations are discussed.

Amantadine-resistant influenza A in nursing homes. Identification of a resistant virus prior to drug use

BACKGROUND

Amantadine hydrochloride and rimantadine hydrochloride have been used for treatment and prevention of influenza A infection in nursing home residents. Outbreaks of influenza A (H3N2) virus infection occurred in three nursing homes in Yakima County, Washington, during January 1992. Amantadine was used for case treatment and prophylaxis in all three nursing homes.

METHODS

Ten influenza A (H3N2) viruses isolated during the outbreaks were examined for resistance to amantadine and rimantadine by means of an enzyme immunoassay and by sequencing of the viral nucleic acid that encodes the transmembrane domain of the M2 protein.

RESULTS

Five of the outbreak strains were resistant and had the same mutation (position 31, serine to asparagine) in the M2 protein. The resistant viruses included one that had been recovered prior to any use of amantadine and another that was recovered within 48 hours of the first drug administration.

CONCLUSIONS

To our knowledge, this is the first report of influenza A virus with RNA sequence-documented resistance to amantadine and rimantadine without exposure to either drug, and the shortest reported period between institution of amantadine therapy and isolation of a resistant influenza A virus strain. These results suggest that surveillance for amantadine- and rimantadine-resistant influenza A is needed, because use of these drugs will probably increase.

Detection of Clostridium botulinum type F using the polymerase chain reaction

The polymerase chain reaction (PCR) was used to amplify a portion of the Clostridium botulinum type F toxin gene. An 1137-bp fragment was amplified from 11 different strains of type F C. botulinum with primers derived from the published sequence of type F strain no. 202. This fragment was not amplified from the DNA of C. botulinum types A, B and E, or from other clostridial organisms examined. When used as a hybridization probe, the 1137-bp PCR-generated fragment generated from one of the type F strains (the proteolytic strain type F Langeland) hybridized to the PCR products from all other type F toxin-producing strains tested. Portions of fragments amplified from the type F Langeland strain were sequenced. The sequence of this strain was found to exhibit approximately 3% variation from the published sequence of the non-proteolytic type F strain no. 202. Primers designed to pair with the regions of maximum sequence variation between strain 202 and the Langeland strain gave amplification products only with DNA from type F strains that exhibited the same proteolytic properties as the strain from which the primer sequences were derived. These findings underscore the need to consider variations in sequence when designing oligonucleotide probes and PCR primers in order to avoid false negative results.

A new, treatable source of recurrent meningitis: basioccipital meningocele

A 19-month-old boy suffered eight episodes of bacterial meningitis. During the ninth episode a meningocele of the basioccipital clivus communicating with the nasopharynx was discovered. Identification of the organism causing the episodes of meningitis was not helpful in pointing to the site of this congenital anatomic defect. Surgical closure of the defect has prevented further recurrences.