Ionizable Lipid Nanoparticles for Therapeutic Base Editing of Congenital Brain Disease

Delivery of mRNA-based therapeutics to the perinatal brain holds great potential in treating congenital brain diseases. However, nonviral delivery platforms that facilitate nucleic acid delivery in this environment have yet to be rigorously studied. Here, we screen a diverse library of ionizable lipid nanoparticles (LNPs) via intracerebroventricular (ICV) injection in both fetal and neonatal mice and identify an LNP formulation with greater functional mRNA delivery in the perinatal brain than an FDA-approved industry standard LNP. Following in vitro optimization of the top-performing LNP (C3 LNP) for codelivery of an adenine base editing platform, we improve the biochemical phenotype of a lysosomal storage disease in the neonatal mouse brain, exhibit proof-of-principle mRNA brain transfection in vivo in a fetal nonhuman primate model, and demonstrate the translational potential of C3 LNPs ex vivo in human patient-derived brain tissues. These LNPs may provide a clinically translatable platform for in utero and postnatal mRNA therapies including gene editing in the brain.

Effectiveness of online education for recruitment to an Alzheimer's disease prevention clinical trial

INTRODUCTION

Low awareness of Alzheimer's disease (AD) clinical trials is a recruitment barrier. To assess whether online education may affect screening rates for AD prevention clinical trials, we conducted an initial prospective cohort study (n = 10,450) and subsequent randomized study (n = 351) using an online digital tool: AlzU.org.

METHODS

A total of 10,450 participants were enrolled in an initial cohort study and asked to complete a six-lesson course on AlzU.org, as well as a baseline and 6-month follow-up questionnaire. Participants were stratified into three groups based on lesson completion at 6 months: group 1 (zero to one lesson completed), group 2 (two to four lessons), and group 3 (five or more lessons). For the subsequent randomized-controlled trial (RCT), 351 new participants were enrolled in a six-lesson course (n = 180) versus a time-neutral control (n = 171). Screening and enrollment in the Anti-Amyloid Treatment in Asymptomatic AD (A4) clinical trial were reported via the 6-month questionnaire and are the primary outcomes.

RESULTS

Cohort: 3.9% of group 1, 5% of group 2, and 8.4% of group 3 screened for the A4 trial. Significant differences were found among the groups (P < 0.001). Post hoc analyses showed differences in A4 screening rates between groups 1 and 3 (P < 0.001) and groups 2 and 3 (P = 0.0194). There were no differences in enrollment among the three groups. RCT: 2.78% of the intervention group screened for A4 compared to 0% of controls (P = 0.0611).

DISCUSSION

Online education via the AlzU.org digital tool may serve as an effective strategy to supplement clinical trial recruitment.

Individualized clinical management of patients at risk for Alzheimer's dementia

INTRODUCTION

Multidomain intervention for Alzheimer's disease (AD) risk reduction is an emerging therapeutic paradigm.

METHODS

Patients were prescribed individually tailored interventions (education/pharmacologic/nonpharmacologic) and rated on compliance. Normal cognition/subjective cognitive decline/preclinical AD was classified as Prevention. Mild cognitive impairment due to AD/mild-AD was classified as Early Treatment. Change from baseline to 18 months on the modified Alzheimer's Prevention Cognitive Composite (primary outcome) was compared against matched historical control cohorts. Cognitive aging composite (CogAging), AD/cardiovascular risk scales, and serum biomarkers were secondary outcomes.

RESULTS

One hundred seventy-four were assigned interventions (age 25-86). Higher-compliance Prevention improved more than both historical cohorts (P = .0012, P < .0001). Lower-compliance Prevention also improved more than both historical cohorts (P = .0088, P < .0055). Higher-compliance Early Treatment improved more than lower compliance (P = .0007). Higher-compliance Early Treatment improved more than historical cohorts (P < .0001, P = .0428). Lower-compliance Early Treatment did not differ (P = .9820, P = .1115). Similar effects occurred for CogAging. AD/cardiovascular risk scales and serum biomarkers improved.

DISCUSSION

Individualized multidomain interventions may improve cognition and reduce AD/cardiovascular risk scores in patients at-risk for AD dementia.

The clinical practice of risk reduction for Alzheimer's disease: A precision medicine approach

Like virtually all age-related chronic diseases, late-onset Alzheimer's disease (AD) develops over an extended preclinical period and is associated with modifiable lifestyle and environmental factors. We hypothesize that multimodal interventions that address many risk factors simultaneously and are individually tailored to patients may help reduce AD risk. We describe a novel clinical methodology used to evaluate and treat patients at two Alzheimer's Prevention Clinics. The framework applies evidence-based principles of clinical precision medicine to tailor individualized recommendations, follow patients longitudinally to continually refine the interventions, and evaluate N-of-1 effectiveness (trial registered at ClinicalTrials.gov NCT03687710). Prior preliminary results suggest that the clinical practice of AD risk reduction is feasible, with measurable improvements in cognition and biomarkers of AD risk. We propose using these early findings as a foundation to evaluate the comparative effectiveness of personalized risk management within an international network of clinician researchers in a cohort study possibly leading to a randomized controlled trial.

Female Sex and Alzheimer's Risk: The Menopause Connection

Along with advanced age and apolipoprotein E (APOE)-4 genotype, female sex is a major risk factor for developing late-onset Alzheimer's disease (AD). Considering that AD pathology begins decades prior to clinical symptoms, the higher risk in women cannot simply be accounted for by their greater longevity as compared to men. Recent investigation into sex-specific pathophysiological mechanisms behind AD risk has implicated the menopause transition (MT), a midlife neuroendocrine transition state unique to females. Commonly characterized as ending in reproductive senescence, many symptoms of MT are neurological, including disruption of estrogen-regulated systems such as thermoregulation, sleep, and circadian rhythms, as well as depression and impairment in multiple cognitive domains. Preclinical studies have shown that, during MT, the estrogen network uncouples from the brain bioenergetic system. The resulting hypometabolic state could serve as the substrate for neurological dysfunction. Indeed, translational brain imaging studies demonstrate that 40-60 year-old perimenopausal and postmenopausal women exhibit an AD-endophenotype characterized by decreased metabolic activity and increased brain amyloid-beta deposition as compared to premenopausal women and to age-matched men. This review discusses the MT as a window of opportunity for therapeutic interventions to compensate for brain bioenergetic crisis and combat the subsequent increased risk for AD in women.

Nutritional interventions for Alzheimer's prevention: a clinical precision medicine approach

Alzheimer's disease (AD) is a major source of morbidity and mortality, with the disease burden expected to rise as the population ages. No disease-modifying agent is currently available, but recent research suggests that nutritional and lifestyle modifications can delay or prevent the onset of AD. However, preventive nutritional interventions are not universally applicable and depend on the clinical profile of the individual patient. This article reviews existing nutritional modalities for AD prevention that act through improvement of insulin resistance, correction of dyslipidemia, and reduction of oxidative stress, and discusses how they may be modified on the basis of individual biomarkers, genetics, and behavior. In addition, we report preliminary results of clinical application of these personalized interventions at the first AD prevention clinic in the United States. The use of these personalized interventions represents an important application of precision medicine techniques for the prevention of AD that can be adopted by clinicians across disciplines.

Differential effects of volatile and intravenous anesthetics on the activity of human TASK-1

Volatile anesthetics have been shown to activate various two-pore (2P) domain K(+) (K(2P)) channels such as TASK-1 and TREK-1 (TWIK-related acid-sensitive K(+) channel), and mice deficient in these channels are resistant to halothane-induced anesthesia. Here, we investigated whether K(2P) channels were also potentially important targets of intravenous anesthetics. Whole cell patch-clamp techniques were used to determine the effects of the commonly used intravenous anesthetics etomidate and propofol on the acid-sensitive K(+) current in rat ventricular myocytes (which strongly express TASK-1) and selected human K(2P) channels expressed in Xenopus laevis oocytes. In myocytes, etomidate decreased both inward rectifier K(+) (K(ir)) current (I(K1)) and acid-sensitive outward K(+) current at positive potentials, suggesting that this drug may inhibit TASK channels. Indeed, in addition to inhibiting guinea pig Kir2.1 expressed in oocytes, etomidate inhibited human TASK-1 (and TASK-3) in a concentration-dependent fashion. Propofol had no effect on human TASK-1 (or TASK-3) expressed in oocytes. Moreover, we showed that, similar to the known effect of halothane, sevoflurane and the purified R-(-)- and S-(+)-enantiomers of isoflurane, without stereoselectivity, activated human TASK-1. We conclude that intravenous and volatile anesthetics have dissimilar effects on K(2P) channels. Human TASK-1 (and TASK-3) are insensitive to propofol but are inhibited by supraclinical concentrations of etomidate. In contrast, stimulatory effects of sevoflurane and enantiomeric isoflurane on human TASK-1 can be observed at clinically relevant concentrations.

Adolescent medicine training in pediatric residency programs: are we doing a good job?

OBJECTIVES

To determine how pediatric residency programs are responding to the new challenges of teaching adolescent medicine (AM) to residents by assessing whether manpower is adequate for training, whether AM curricula and skills are adequately covered by training programs, what types of teaching methodologies are used to train residents in AM, and the needs for new curricular materials to teach AM.

DESIGN

A 3-part 92-item survey mailed to all US pediatric residency training programs.

SETTING

Pediatric residency programs.

PARTICIPANTS

Residency program directors and directors of AM training.

MAIN OUTCOME MEASURES

AM divisional structure, clinical sites of training, presence of a block rotation, and faculty of pediatric training programs; training materials used and desired in AM; perceived adequacy of coverage of various AM topics; competency of residents in performing pelvic examinations in sexually active teens; and manpower needs.

RESULTS

A total of 155/211 (73.5%) of programs completed the program director and the AM parts of the survey. Ninety-six percent of programs (size range, 5-120 residents) had an AM block rotation and 90% required the AM block; those without a block rotation were more likely to be larger programs. Only 39% of programs felt that the number of AM faculty was adequate for teaching residents. Almost half of the programs reported lack of time, faculty, and curricula to teach content in substance abuse. Besides physicians, AM teachers included nurse practitioners (28%), psychologists (25%), and social workers (19%). Topics most often cited as adequately covered included sexually transmitted diseases (81.9%), confidentiality (79.4%), puberty (77.0%), contraception (76.1%), and menstrual problems (73.5%). Topics least often cited as adequately covered included psychological testing (16.1%), violence in relationships (20.0%), violence and weapon-carrying (29.7%), and sports medicine (29.7%). Fifty-eight percent of 137 respondents thought that all or nearly all of their residents were competent in performing pelvic examinations by the end of training; there was no difference between perceived competence and the residents' use of procedure books. Seventy-four percent used a specific curriculum for teaching AM; materials included chapters/articles (85%), lecture outlines (76.1%), slides (41.9%), videos (35.5%), written case studies (24.5%), computerized cases (6.5%), and CD-ROMs (3.2%). Fifty-two percent used Bright Futures, 48% used the Guidelines for Adolescent Preventive Services, and 14% used the Guide to Clinical Preventive Services for teaching clinical preventive services. Programs that used Bright Futures were more likely to feel that preventive services were adequately covered in their programs than those who did not (78% vs 57%). A majority of programs desired more learner-centered materials.

CONCLUSIONS

Although almost all pediatric programs are now providing AM rotations, there is significant variability in adequacy of training across multiple topics important for resident education. Programs desire more learner-centered materials and more faculty to provide comprehensive resident education in AM.

Families of borderline patients: a psychoeducational approach

The development of the psychoeducational form of treatment described in this article has been prompted by changes in our understanding of borderline psychopathology and changes in the health care system in which these patients are treated. After reviewing these background changes, the authors describe the treatment itself, its form, its purpose, and the preliminary suggestions of its effectiveness.

Evaluating generalist education programs: a conceptual framework. Generalist program evaluation working group

This paper provides and applies a conceptual framework and a list of guiding principles for evaluation of generalist education programs. Programs are systematic efforts to achieve specified objectives. Evaluations gather data in order to improve or appraise programs and have a continuum of purposes and methods. Descriptive evaluations characterize the structures, processes, and outcomes of programs; research evaluations definitively assess the effectiveness of a program in terms of outcomes. Intermediate outcomes are changes in knowledge, attitudes, and skills of program participants; conclusive outcomes reflect the quality of performance of graduates in actual clinical situations. Outcomes are affected by inputs--the qualities of students entering the program. Guiding principles of program evaluation ensure that data gathered are useful. The authors illustrate the guiding principles with an actual pilot study that determined that expert pediatricians, general internists, and family practitioners could agree on key generalist competencies and that explores evaluation design based on these competencies. Finally, they consider the implications of undertaking generalist education evaluation.

Herpes simplex virus type 1 (HSV-1) UL56 gene is involved in viral intraperitoneal pathogenicity to immunocompetent mice

A comparison of the pathogenicity in mice of the recombinant herpes simplex virus type 1 (HSV-1) strain HSV-1-M-LacZ, in which the UL56 gene has been deleted, was made with its parental strain F, following infection in different mouse strains. The polymerase chain reaction (PCR) technique was used to study the migration of virus DNA in the mouse model. Tissues from adult mice infected intraperitoneally (IP) with one of three HSV-1 strains (F, HFEM or HSV-1-LacZ) were examined for the presence of viral DNA. DNA of the pathogenic strain F was detected in the adrenal glands, spinal cord, brain, liver and pancreas. DNA of HSV-1-M-LacZ was detected in the same tissues. However, DNA of the apathogenic strain HFEM was detected transiently (on days 2 and 3 p.i., but not days 1, 5 or 7), only in the adrenal glands and no viral DNA was detected in any of the other tissues. HSV-1 pathogenic strains injected intraperitoneally into newborn mice (7 days old) killed most of the mice. In the surviving mice viral DNA of the three virus strains was found in peritoneal exudate cells (PEC), adrenal glands, spinal cord, liver and spleen. It was found that HSV-1-M-LacZ, which lacks the UL56 gene, resembled in pathogenicity to the newborn mice the pathogenic HSV-1 strains F and KOS. The PCR technique was used to trace viral DNA in tissues of the mice which survived HSV-1 infection at 7 weeks of age. Only HSV-1 (KOS) DNA was detected in the pancreas. The brains of these mice did not contain viral DNA. It is suggested that HSV-1 DNA may reside in surviving HSV-1- infected newborn mice in a "latent" state in nonneural tissues.

Effect of herpes simplex virus type-1 UL41 gene on the stability of mRNA from the cellular genes: beta-actin, fibronectin, glucose transporter-1, and docking protein, and on virus intraperitoneal pathogenicity to newborn mice

Infection with HSV-1 is accompanied by the shut-off of cellular gene expression. The virion-associated function is encoded by the viral gene UL41. An HSV-1 mutant, vhs-1, which has a genomic deletion in the UL41 gene, is incapable of inducing the shut-off of cellular gene expression. The effect of HSV-1 infection on the shut-off of the cellular genes (or mRNA degradation) was studied specifically with the cellular genes for beta-actin, fibronectin, glucose transporter-1, and the docking protein. The level of these specific mRNAs was measured in cells infected with several HSV-1 strains and was compared to that of vhs-1- and mock-infected cells. It was possible to demonstrate a marked reduction in the level of the specific mRNA from these cellular genes in cells infected with several HSV-1 strains but not with the vhs-1 mutant. The pathogenicity of the HSV-1 vhs-1 mutant to newborn mice was studied. It was found that the mutant is less pathogenic to newborn mice than its parental strain HSV-1 KOS.

Bone marrow-derived dendritic cells and the protection against X-ray-induced thymic leukemia in mice. A new interpretation

About forty years ago, Henry Kaplan and collaborators reported that four weekly X-ray doses of 160 rads each were highly leukemogenic in C57BL mice. A single dose of 350 Rads had a week leukemogenic effect. These authors also demonstrated that lead shielding of the thigh during irradiation prevented the development of leukemia. They reported that intravenous injection of syngeneic bone marrow cells into irradiated mice facilitated the regeneration of the thymus and prevented the development of X-ray-induced tumors. We characterized the thymic Ia+ dendritic cells (DC) with the aid of a fluorescence-activated cell-sorter (FACS). It was found that exposure of mice to a leukemogenic regimen of fractionated X-irradiation treatment led to a gradual decrease in the number of thymic DC. The disappearance of thymic DC and the development of leukemia were prevented by intravenous injection of syngeneic bone marrow or by lead shielding of the femur during irradiation. These results indicated that the fractionated irradiation caused a decline in the number of DC and, as a result, diminution of the natural defense against the developing tumor. Homing of the injected bone marrow DC into the thymus can be connected to the prevention of tumor development. Since leukemogenic T cells produce interleukin-4(IL-4), we tested the effect of the conditioned medium in which YAB-3 cells (tumorigenic Th cells: CD4+, CD8-, Thy-1+) were cultivated. Following injection of the conditioned medium into the mouse footpads, the number of skin Langerhans cells (LC) decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

Mutations in the UL53 gene of HSV-1 abolish virus neurovirulence to mice by the intracerebral route of infection

The cell fusion protein, the product of the UL53 gene, is responsible for intracerebral (IC) pathogenicity of HSV-1. Recombinant HSV-1 R15 is apathogenic to mice by the IC route of inoculation, while intratypic recombinants, in which the UL53 gene in R15 was replaced by an analogous sequence from the pathogenic strain R19, regained IC pathogenicity. The nucleotide sequence of the UL53 gene of HSV-1 strains R15 (apathogenic) and R19 (pathogenic) was determined and compared to that of other pathogenic strains. Four mutations were found which are thought to be responsible for the apathogenic phenotype of HSV-1 strain R15. Northern blot hybridization of RNA extracted from BSC-1 cells infected with several HSV-1 strains indicated that all of the virus strains tested expressed equal amounts of UL53 mRNA in infected cell cultures. Demonstration of the expression of UL53 mRNA in brains of mice infected with HSV-1 strains was made possible by the combined use of a rapid method for mRNA extraction (Oligo dT-linked magnetic beads) and a highly sensitive technique for detection of the existence of the UL53-specific mRNA (cDNA synthesis followed by PCR). It was shown that both pathogenic (KOS and P42) and apathogenic (R15) HSV-1 strains expressed the UL53 gene in brains of IC infected mice.

Recombinant interleukin-1 alpha, interleukin-2 and M-CSF-1 enhance the survival of newborn C57BL/6 mice inoculated intraperitoneally with a lethal dose of herpes simplex virus-1

Recombinant Interleukin-1 alpha (IL-1 alpha), Interleukin-2 (IL-2) and recombinant macrophage colony-stimulating factor-1 (M-CSF-1) as well as combinations of IL-2 and M-CSF-1 were studied for their ability to protect seven-day-old C57BL/6 mice against HSV-1 infection. Treatment of the mice with IL-2, M-CSF-1 or combinations of IL-2 and M-CSF-1 significantly increased survival rates. Treatment with IL-1 alpha (10 U and 100 U/mouse) was most effective in protection against HSV-1, resulting in significantly increased survival rates more than four times greater than the survival rate of the infected control group.

Elimination of UL56 gene by insertion of LacZ cassette between nucleotide position 116030 to 121753 of the herpes simplex virus type 1 genome abrogates intraperitoneal pathogenicity in tree shrews and mice

In order to investigate whether or not the UL56 gene is involved in those processes determining the viral pathogenicity and latency, a recombinant virus HSV-1-M-LacZ was constructed in which the DNA sequences between nucleotide position (np) 116030 and 121753 were replaced by the E. coli beta-galactosidase (LacZ) gene. This deletion spans from the carboxyterminus of UL55 (np 116030) to the second exon of IE110 (np 121753) eliminating UL56 and the variable region of the BamHI DNA fragment B which were implicated in intraperitoneal pathogenicity and latency. The host range and growth kinetics of the recombinant virus HSV-1 M-LacZ were comparable to the parental strain HSV-1 F. As expected it was found that HSV-1-M-LacZ lost its virulent phenotype and was not able to develop acute infection in animals. The state of the UL56 gene was investigated by determining the cDNA sequence of the UL56 gene transcript of HSV-1 F using PCR products obtained after amplification of the cDNA with oligonucleotide primers corresponding to the translational start and stop codons of this gene. This analysis revealed that the DNA sequence of the UL56 gene of HSV-1 F differed from those DNA sequences determined for the genomic DNA of HSV-1 strain 17. Between nucleotide position 116343 and 116344 two nucleotides -AG- are inserted which prolong the ORF of the UL56 gene to 233 amino acids with a predicted molecular weight of 30 kDa.

Comparative responses to dobutamine and nitroprusside in patients with chronic low output cardiac failure

The acute hemodynamic effects of dobutamine and nitroprusside were compared in 19 patients with low output cardiac failure. At dosage levels yielding similar increases in cardiac index (12 patients), nitroprusside resulted in significantly lower arterial systolic and wedge pressures and did not increase heart rate suggesting advantages over dobutamine when reduction in myocardial oxygen requirement or pulmonary congestion is a major goal. Systemic arterial mean and diastolic pressures were minimally changed with dobutamine, but fell significantly with nitroprusside suggesting advantages of dobutamine over nitroprusside in patients where hypotension could limit coronary blood flow or perfusion of other vital organs. Reduction in pulmonary arteriolar resistance occurred only with nitroprusside. Arterial hypoxemia developed in three patients during nitroprusside infusion suggesting the possibility of increased right-to-left intrapulmonary shunting resulting from a direct vasodilating effect of nitroprusside on pulmonary arteriole smooth muscle. Although both inotropic and vasodilator drugs can result in hemodynamic improvement when administered to patients with chronic low output cardiac failure, significant differences of potential clinical importance exist between these two modes of therapy.

Hazards of overconcentrated milk formula. Hyperosmolality, disseminated intravascular coagulation and gangrene

Severe hypertonic dehydration with hyperglycemia developed in a 7-week-old infant girl after she was fed an overconcentrated milk formula for five days. Renal failure,disseminated intravascular coagulation, gangrene of the legs, and coma were added complications. Intravenous rehydration, peritoneal dialysis, and heparin administration corrected the metabolic and coagulation derangements, and renal function returned to normal. Bilateral below-the-knee amputations were performed and the child subsequently learned to walk with artificial limbs. The dangers of overconcentrated formulas in infant feeding should be widely publicized through warnings printed on all commercial milk preparations.