Virtual Compared With In-Clinic Transvaginal Ultrasonography for Ovarian Reserve Assessment.

OBJECTIVE: To evaluate noninferiority of virtual transvaginal ultrasonography compared with in-clinic ultrasonography for ovarian reserve assessment. METHODS: We conducted a single-site, head-to-head crossover trial. Participants performed self-administered virtual transvaginal ultrasonography at home, guided by a remote-certified ultrasound technologist, then underwent transvaginal ultrasonography in-clinic with another ultrasound technologist. Participants were women in the greater Boston area interested in evaluating ovarian reserve and recruited through social media, health care referrals, and professional networks. The uterus and ovaries were captured in sagittal and transverse views. These randomized recordings were reviewed by two or three independent, blinded reproductive endocrinologists. The primary outcome was noninferiority of the rate of clinical quality imaging produced at home compared with in clinic. Sample size was selected for greater than 90% power, given the 18% noninferiority margin. Secondary outcomes included antral follicle count equivalency and net promoter score superiority. RESULTS: Fifty-six women were enrolled from December 2020 to May 2021. Participants varied in age (19-35 years), BMI (19.5-33.9), and occupation. Ninety-six percent of virtual and 98% of in-clinic images met "clinical quality." The difference of -2.4% (97.5% CI lower bound -5.5%) was within the noninferiority margin (18%). Antral follicle counts were equivalent across settings, with a difference in follicles (0.23, 95% CI -0.36 to 0.82) within the equivalence margin (2.65). Virtual examinations had superior net promoter scores (58.1 points, 97.5% CI of difference 37.3-79.0, P<.01), indicating greater satisfaction with the virtual experience. CONCLUSION: Virtual transvaginal ultrasonography remotely guided by an ultrasonography technologist is noninferior to in-clinic transvaginal ultrasonography for producing clinical quality images and is equivalent for estimating antral follicle count. Virtual transvaginal ultrasonography had superior patient satisfaction and has potential to significantly expand patient access to fertility care. FUNDING SOURCE: This study was sponsored by Turtle Health. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT04687189.

Targeting Nanoparticles to Bioengineered Human Vascular Networks.

Pharmacotherapy of vascular anomalies has limited efficacy and potentially limiting toxicity. Targeted nanoparticle (NP) drug delivery systems have the potential to accumulate within tissues where the vasculature is impaired, potentially leading to high drug levels (increased efficacy) in the diseased tissue and less in off-target sites (less toxicity). Here, we investigate whether NPs can be used to enhance drug delivery to bioengineered human vascular networks (hVNs) that are a model of human vascular anomalies. We demonstrate that intravenously injected phototargeted NPs enhanced accumulation of NPs and the drug within hVNs. With phototargeting we demonstrate 17 times more NP accumulation within hVNs than was detected in hVNs without phototargeting. With phototargeting there was 10-fold more NP accumulation within hVNs than in any other organ. Phototargeting resulted in a 6-fold increase in drug accumulation (doxorubicin) within hVNs in comparison to animals injected with the free drug. Nanoparticulate approaches have the potential to markedly improve drug delivery to vascular anomalies.

Local anesthesia enhanced with increasing high-frequency ultrasound intensity.

The effect of local anesthetics, particularly those which are hydrophilic, such as tetrodotoxin, is impeded by tissue barriers that restrict access to individual nerve cells. Methods of enhancing penetration of tetrodotoxin into nerve include co-administration with chemical permeation enhancers, nanoencapsulation, and insonation with very low acoustic intensity ultrasound and microbubbles. In this study, we examined the effect of acoustic intensity on nerve block by tetrodotoxin and compared it to the effect on nerve block by bupivacaine, a more hydrophobic local anesthetic. Anesthetics were applied in peripheral nerve blockade in adult Sprague-Dawley rats. Insonation with 1-MHz ultrasound at acoustic intensity greater than 0.5 W/cm2 improved nerve block effectiveness, increased nerve block reliability, and prolonged both sensory and motor nerve blockade mediated by the hydrophilic ultra-potent local anesthetic, tetrodotoxin. These effects were not enhanced by microbubbles. There was minimal or no tissue injury from ultrasound treatment. Insonation did not enhance nerve block from bupivacaine. Using an in vivo model system of local anesthetic delivery, we studied the effect of acoustic intensity on insonation-mediated drug delivery of local anesthetics to the peripheral nerve. We found that insonation alone (at intensities greater than 0.5 W/cm2) enhanced nerve blockade mediated by the hydrophilic ultra-potent local anesthetic, tetrodotoxin. Graphical abstract.

The Duration of Nerve Block from Local Anesthetic Formulations in Male and Female Rats.

PURPOSE: It is unknown whether there are sex differences in response to free or encapsulated local anesthetics. METHODS: We examined nerve block duration and toxicity following peripheral nerve blockade in male and female rats. We studied the local anesthetic bupivacaine (free or encapsulated) as well as tetrodotoxin, which acts on a different site of the same voltage-gated channel. RESULTS: Sensory nerve blockade was 158.5 [139-190] minutes (median [interquartile range]) (males) compared to 173 [134-171] minutes (females) (p = 0.702) following bupivacaine injection, N = 8 male, 8 female. Motor nerve blockade was 157 [141-171] minutes (males) compared to 172 [146-320] minutes (females) (p = 0.2786). Micellar bupivacaine (N = 8 male, 8 female) resulted in sensory nerve blockade of 266 [227-320] minutes (males) compared to 285 [239-344] minutes (females) (p = 0.6427). Motor nerve blockade was 264 [251-264] minutes (males) compared to 287 [262-287] minutes (females) (p = 0.3823). Liposomal bupivacaine (N = 8 male, 8 female) resulted in sensory nerve blockade of 240 [207-277] minutes (males) compared to 289 [204-348] minutes (females) (p = 0.1654). Motor nerve blockade was 266 [237-372] minutes (males) compared to 317 [251-356] minutes (females) (p = 0.6671). Following tetrodotoxin injection (N = 12 male,12 female) sensory nerve blockade was 54.8 [5-117] minutes (males) compared to 54 [14-71] minutes (females) (p = 0.6422). Motor nerve blockade was 72 [40-112] minutes (males) compared to 64 [32-143] minutes (females) (p = 0.971). CONCLUSIONS: We found no statistically significant sex differences associated with the formulations tested. In both sexes, durations of nerve block were similar between micellar and liposomal bupivacaine formulations, despite the micellar formulation containing less drug.

Cytoplasmic transport and nuclear import of plasmid DNA.

Productive transfection and gene transfer require not simply the entry of DNA into cells and subsequent transcription from an appropriate promoter, but also a number of intracellular events that allow the DNA to move from the extracellular surface of the cell into and through the cytoplasm, and ultimately across the nuclear envelope and into the nucleus before any transcription can initiate. Immediately upon entry into the cytoplasm, naked DNA, either delivered through physical techniques or after disassembly of DNA-carrier complexes, associates with a large number of cellular proteins that mediate subsequent interactions with the microtubule network for movement toward the microtubule organizing center and the nuclear envelope. Plasmids then enter the nucleus either upon the mitotic disassembly of the nuclear envelope or through nuclear pore complexes in the absence of cell division, using a different set of proteins. This review will discuss our current understanding of these pathways used by naked DNA during the transfection process. While much has been elucidated on these processes, much remains to be discerned, but with the development of a number of model systems and approaches, great progress is being made.