Molecular determinants and signaling effects of PKA RIα phase separation.

Spatiotemporal regulation of intracellular signaling molecules, such as the 3',5'-cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA), ensures proper cellular function. Liquid-liquid phase separation (LLPS) of the ubiquitous PKA regulatory subunit RIα promotes cAMP compartmentation and signaling specificity. However, the molecular determinants of RIα LLPS remain unclear. Here, we reveal that two separate dimerization interfaces, combined with the cAMP-induced unleashing of the PKA catalytic subunit (PKA-C) from the pseudosubstrate inhibitory sequence, drive RIα condensate formation in the cytosol of mammalian cells, which is antagonized by docking to A-kinase anchoring proteins. Strikingly, we find that the RIα pseudosubstrate region is critically involved in forming a non-canonical R:C complex, which recruits active PKA-C to RIα condensates to maintain low basal PKA activity in the cytosol. Our results suggest that RIα LLPS not only facilitates cAMP compartmentation but also spatially restrains active PKA-C, thus highlighting the functional versatility of biomolecular condensates in driving signaling specificity.

A teenage girl with altered mental status and paraparesis.

A teenage girl presented with fever and altered mental status. MRI showed diffuse leptomeningeal enhancement of the brain and spine. She was diagnosed by a positive cerebrospinal fluid (CSF) culture with tuberculous (TB) meningitis and was started on anti-TB medications and corticosteroids. Her mental status improved, but she was noted to have proximal weakness of the lower extremities. In the course of tapering corticosteroids at week 11 of anti-TB therapy, she became acutely confused and febrile. MRI demonstrated interval development of tuberculomas in the brain and a mass lesion in the thoracic spine causing cord compression. Given the clinical picture was suggestive of a paradoxical reaction, the dose of corticosteroids was increased. Infliximab was added when repeat MRI revealed enlargement of the mass lesion in the spine with worsening cord compression. She was successfully tapered off of corticosteroids. Over several months, the patient's motor function recovered fully, and she returned to ambulating without assistance.

Elongation of intercostal nerve cutaneous branches for breast and nipple neurotization during breast reconstruction after mastectomy for breast cancer: case-control study.

BACKGROUND: To restore sensation after breast reconstruction, a modified surgical approach was employed by identifying the cut fourth intercostal lateral cutaneous branch, elongating it with intercostal nerve grafts, and coapting it to the innervating nerve of the flap or by using direct neurotization of the spared nipple/skin. METHODS: This was a retrospective case-control study including 56 patients who underwent breast neurotization surgery. Breast operations included immediate reconstruction after nipple-sparing mastectomy (36 patients), skin-sparing mastectomy (8 patients), and delayed reconstruction with nipple preservation (7 patients) or without nipple preservation (5 patients). Patients who underwent breast reconstruction without neurotization were included as the non-neurotization negative control group. The contralateral normal breasts were included as positive controls. RESULTS: The mean(s.d.) monofilament test values were 0.07(0.10) g for the positive control breasts and 179.13(143.31) g for the breasts operated on in the non-neurotization group. Breasts that underwent neurotization had significantly better sensation after surgery, with a mean(s.d.) value of 35.61(92.63) g (P < 0.001). The mean(s.d.) sensory return after neurotization was gradual; 138.17(143.65) g in the first 6 months, 59.55(116.46) g at 7-12 months, 14.54(62.27) g at 13-18 months, and 0.37(0.50) g at 19-24 months after surgery. Two patients had accidental rupture of the pleura, which was repaired uneventfully. One patient underwent re-exploration due to a lack of improvement 1.5 years after neurotization. CONCLUSION: Using the lateral cutaneous branch of the intercostal nerve as the innervating stump and elongating it with intercostal nerve grafts is a suitable technique to restore sensation after mastectomy. This method effectively innervates reconstructed breasts and spares the nipple/skin with minimal morbidity.

A phase 1 trial of 8-chloro-adenosine in relapsed/refractory acute myeloid leukemia: An evaluation of safety and pharmacokinetics.

BACKGROUND: This study evaluated the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of 8-chloro-adenosine (8-Cl-Ado) in patients with relapsed/refractory acute myeloid leukemia (AML). METHODS: 8-Cl-Ado was administered daily for 5 days; the starting dose was 100 mg/m2 , the highest dose tested was 800 mg/m2 . The end points were toxicity, disease response, and PK/PD measurements. RESULTS: The predominant nonhematologic toxicity was cardiac with grade ≥3 toxicity. Plasma PK in all patients suggested heterogeneity among patients, yet, some dose-dependency for the accumulation of 8-Cl-Ado. Two 8-Cl-Ado metabolites accumulated at similar levels to 8-Cl-Ado. Cellular PK in eight patients indicated accumulation of 8-Cl-ATP, which was associated with AML blast cytoreduction in peripheral blood. The authors determined the RP2D of 8-Cl-Ado to be 400 mg/m2 . CONCLUSIONS: Given the cardiac adverse events observed, patients require monitoring for arrhythmias and QT interval during infusion. Although peripheral blood cytoreduction was observed, responses were transient, suggesting combination strategies will be required.

Robotic sympathetic trunk reconstruction for compensatory sweating after thoracic sympathectomy.

Objectives: Endoscopic thoracic sympathectomy may be complicated by the onset of disabling compensatory sweating (CS). The objective of this case series is to report the 2-year outcomes after robotic sympathetic trunk reconstruction (STR) for the reversal of CS in patients who had undergone endoscopic thoracic sympathectomy. Methods: We prospectively followed-up a total of 23 patients who had undergone robotic STR because of intolerable CS between October 2017 and January 2021. A visual analog scale ranging from 0 to 10 (with 10 indicating the highest degree) was used to assess the severity of CS at different anatomical locations, thermoregulatory alterations, and gustatory hyperhidrosis. Measurements were performed before STR and at 6-month and 2-year follow-up. Results: The mean age of the study participants was 43.3 ± 7.8 years, and 20 (87%) were men. The reversal procedure was performed after a mean of 19.6 ± 7.8 years from endoscopic thoracic sympathectomy. In all patients, nerve defects were successfully bridged using sural nerves (mean length, 9.7 cm on the right and 9.8 cm on the left). No cases of Horner syndrome were noted. At 6 postoperative months, the severity of CS decreased significantly at all body surface areas. The observed improvements were effectively maintained at 24 post-STR months. There was no evidence of either recurrent hyperhidrosis at the primary site or transition of CS to other anatomical locations. Similar improvements were evident for thermoregulatory alterations and gustatory hyperhidrosis. Conclusions: Robotic STR is safe and effective in reversing intolerable CS after endoscopic thoracic sympathectomy.

Chimerization of Monitor Flap in a Vascularized Ulnar Nerve Flap Is an Efficient Way for Vascularity Monitoring and the Reinnervation Checkup after Its Transplantation.

Background Free vascularized ulnar nerve flaps (VUNF) are effective method for long nerve defects reconstruction. However, the monitorization of its microvascular circulation and the nerve regrowth can be challenging since it is usually designed as a buried flap. We designed a skin paddle based on a septocutaneous perforator from the ulnar artery that can be dissected and raised in conjunction with the vascularized ulnar nerve flap, which aims to improve postoperative monitorization to optimizing the clinical results. Methods We retrospectively reviewed 10 cases with long nerve defects who underwent reconstruction using VUNF between June 2018 and June 2019, including eight acute brachial plexus injuries, 1 multiple nerve injury due to a rolling machine accident, and 1 sequalae of nerve injury after arm replantation. All the demographic data, surgical details, outcomes, and perioperative complications were recorded. Results We evaluated 10 male patients, with a mean age of 34 ± 16 years. Cases included 5 antegrade, 4 retrograde, and 1 U-shaped VUNF. All chimeric skin paddles survived, and all of the underlying nerves presented with adequate circulation and functional improvement. There were no intraoperative or microvascular complications. One skin paddle had a transitory postoperative circulation compromise due to external compression (bandage) which resolved spontaneously after pressure release. Conclusion VUNF chimerization of a septocutaneous perforator skin flap is a relatively easy and efficient method for postoperative monitorization of the nerve's microvascular circulation as well as beneficial for postoperative Tinel's sign checkup to confirm the success of the nerve coaptation. The outcome is potentially improved.

Implementation of Bedaquiline, Pretomanid, and Linezolid in the United States: Experience Using a Novel All-Oral Treatment Regimen for Treatment of Rifampin-Resistant or Rifampin-Intolerant Tuberculosis Disease.

BACKGROUND: Rifampin-resistant tuberculosis is a leading cause of morbidity worldwide; only one-third of persons start treatment, and outcomes are often inadequate. Several trials demonstrate 90% efficacy using an all-oral, 6-month regimen of bedaquiline, pretomanid, and linezolid (BPaL), but significant toxicity occurred using 1200-mg linezolid. After US Food and Drug Administration approval in 2019, some US clinicians rapidly implemented BPaL using an initial 600-mg linezolid dose adjusted by serum drug concentrations and clinical monitoring. METHODS: Data from US patients treated with BPaL between 14 October 2019 and 30 April 2022 were compiled and analyzed by the BPaL Implementation Group (BIG), including baseline examination and laboratory, electrocardiographic, and clinical monitoring throughout treatment and follow-up. Linezolid dosing and clinical management was provider driven, and most patients had linezolid adjusted by therapeutic drug monitoring. RESULTS: Of 70 patients starting BPaL, 2 changed to rifampin-based therapy, 68 (97.1%) completed BPaL, and 2 of the 68 (2.9%) experienced relapse after completion. Using an initial 600-mg linezolid dose daily adjusted by therapeutic drug monitoring and careful clinical and laboratory monitoring for adverse effects, supportive care, and expert consultation throughout BPaL treatment, 3 patients (4.4%) with hematologic toxicity and 4 (5.9%) with neurotoxicity required a change in linezolid dose or frequency. The median BPaL duration was 6 months. CONCLUSIONS: BPaL has transformed treatment for rifampin-resistant or intolerant tuberculosis. In this cohort, effective treatment required less than half the duration recommended in 2019 US guidelines for drug-resistant tuberculosis. Use of individualized linezolid dosing and monitoring likely enhanced safety and treatment completion. The BIG cohort demonstrates that early implementation of new tuberculosis treatments in the United States is feasible.

Heterotopic Digital Replantation in Mutilating Hand Injuries: An Algorithmic Approach Based on 53 Cases and Literature Review.

BACKGROUND: Reconstruction of the mutilated hand is one of the most difficult challenges for hand microsurgeons. When multiple digits are amputated, orthotopic digital replantation of the available remnants may not adequately restore the hand function. In such cases, heterotopic digital replantation may provide a more functional reconstruction. METHODS: Between 1997 and 2018, 53 patients with mutilating hand injuries were treated with heterotopic digital replantation at our institution. A retrospective chart review was conducted to determine the details of the injury, indications for heterotopic digital replantation, and functional outcomes. RESULTS: In total, 173 digits were amputated from 53 patients (one patient suffered from bilateral hand injuries, so totally 54 hands). Sixty-eight digits underwent heterotopic digital replantation, 30 digits had orthotopic digital replantation, and 75 stumps were terminalized. The survival rate of digits treated by heterotopic digital replantation and orthotopic digital replantation was 83.8% (57/68) and 86.7% (26/30), respectively (p = 1). Tripod grip was achieved in 83.3% (45/54) of patients following replantation and optional secondary reconstructive surgeries. CONCLUSION: Heterotopic digital replantation is a practical and reliable method for achieving optimal hand function following mutilating hand injuries. The basic principles are to restore a functional thumb in the first instance, followed by at least two adjacent fingers against which the thumb can oppose. This method is particularly indicated when orthotopic digital replantation of the available amputated parts would yield a suboptimal result.

The Preferred Reconstructive Choice for a Lower Third Tibial Exposure Defect: An Online Survey of 356 Microsurgeons.

BACKGROUND: One of the most challenging yet common areas in reconstructive surgery is the closure of defects in the lower leg. Surgeons can choose from several reconstructive options including local and free flaps. The aim of this study was to understand the reconstructive strategy for lower leg defects of different microsurgeons around the world by harnessing the power of social media and online questionnaires. METHODS: A case of a patient with an exposed plate over distal tibial fracture was presented via an online questionnaire distributed on various social media platforms. A total of 369 international microsurgeons replied with their preferred treatment choice. The data were analyzed according to geographic area, microsurgical training, seniority, and subspecialty. RESULTS: Among all the respondents (n = 369), 64% would have opted for a free flap reconstruction, while the remaining 36% would have opted for a local/pedicle flap. In the group that would have opted for a free flap, 63% would reconstruct the defect using a free fasciocutaneous flap, while the remaining 37% would have used a free muscle flap. In the local flap group, 60% would have used a local perforator while 30% would have chosen a conventional local flap. While North American and European microsurgeons had a clear preference toward free flaps, Asian, Middle Eastern, African, and South American surgeons were evenly divided between local and free flaps. CONCLUSION: In this study, we provide a current global overview of the reconstructive strategies for a lower limb with skin defect and bone or prosthesis exposure. We hope that this will be able to help global microsurgeons and patients worldwide.

Exposure to behavioral regularities in everyday life predicts infants' acquisition of mental state vocabulary.

There are two broad views of children's theory of mind. The mentalist view is that it emerges in infancy and is possibly innate. The minimalist view is that it emerges more gradually in childhood and is heavily dependent on learning. According to minimalism, children initially understand behaviors rather than mental states, and they are assisted in doing so by recognizing repeating patterns in behavior. The regularities in behavior allow them to predict future behaviors, succeed on theory-of-mind tasks, acquire mental state words, and eventually, understand the mental states underlying behavior. The present study provided the first clear evidence for the plausibility of this view by fitting head cameras to 54 infants aged 6 to 25 months, and recording their view of the world in their daily lives. At 6 and 12 months, infants viewed an average of 146.5 repeated behaviors per hour, a rate consistent with approximately 560,000 repetitions in their first year, and with repetitions correlating with children's acquisition of mental state words, even after controlling for their general vocabulary and a range of variables indexing social interaction. We also recorded infants' view of people searching or searching for and retrieving objects. These were 92 times less common and did not correlate with mental state vocabulary. Overall, the findings indicate that repeated behaviors provide a rich source of information for children that would readily allow them to recognize patterns in behavior and help them acquire mental state words, providing the first clear evidence for this claim of minimalism. RESEARCH HIGHLIGHTS: Six- to 25-month-olds wore head cameras to record home life from infants' point-of-view and help adjudicate between nativist and minimalist views of theory-of-mind (ToM). Nativists say ToM is too early developing to enable learning, whereas minimalists say infants learn to predict behaviors from behavior patterns in environment. Consistent with minimalism, infants had an incredibly rich exposure (146.5/h, >560,000 in first year) to repeated behaviors (e.g., drinking from a cup repeatedly). Consistent with minimalism, more repeated behaviors correlated with infants' mental state vocabulary, even after controlling for gender, age, searches witnessed and non-mental state vocabulary.

Double Fascicular Transfer Using Partially Injured Donor Nerves: Is It Powerful Enough to Restore Elbow Flexion in Acute Brachial Plexus Injuries?

BACKGROUND: Loss of elbow flexion is a common sequela of acute brachial plexus injuries (BPIs). The Mackinnon/Oberlin-II double fascicular transfer (DFT) is a widely used method to restore this function in acute C5-6 or C5-7 injuries. This study attempted to evaluate if this technique can be applied reliably for cases involving C8 and/or T1 injuries. METHODS: Adult patients with acute BPIs who underwent the Mackinnon/Oberlin-II DFT in our center between 2008 and 2018 were retrospectively identified. Group I (n = 37) included patients with only C5-6 or C5-7 injury, while group II (n = 32) patients presented C5-8 ± T1 injuries. The demographic data, pre- and postoperative neurologic evaluations, electrodiagnostic studies, and grip strength assessment were collected. RESULTS: A total of 69 patients met the inclusion criteria. Preoperatively, the patients in group II presented poorer nerve conduction and electromyography in both the median and the ulnar nerves and the supply muscles. The percentage of M3 achievement in both groups was 91.9 versus 87.5% and M4 was 73.0 and 71.9%, respectively, which both were not statically significant but the achievement of group II was slower than the group I, 1 to 2 months slower, respectively. Both groups had 57.57 and 46.0% of the postoperative grip power compared with the healthy side, the result of shoulder abduction was not different (p = 0.480). CONCLUSION: With careful preoperative evaluation, early intervention, appropriate intraoperative functional fascicle selection, and aggressive postoperative rehabilitation, indications for the Mackinnon/Oberlin-II DFT technique can safely include acute C5-8 injuries and even partial T1 acute BPIs.

Multi-Objective Design Automation for Microfluidic Capture Chips.

Microfluidic capture chips are useful for preparing or analyzing a wide range of different chemical, biological, and medical samples. A typical microfluidic capture chip contains features that capture certain targets (i.e. molecules, particles, cells) as they flow through the chip. However, creating optimal capture chip designs is difficult because of the inherent relationship between capture efficiency and flow resistance: as more capture features are added to the chip, the capture efficiency increases, but the additional features slow the flow of fluid through the chip. This paper introduces the use of multi-objective optimization to generate capture chip designs that balance the trade-off between maximizing target capture efficiency and minimizing resistance to fluid flow. Design automation for this important class of microfluidic chips has not been attempted previously. Our approach automatically produces a Pareto front of non-dominated chip designs in a reasonable amount of time, and most of these designs have comparable capture efficiency to hand-designed chips with far lower flow resistance. By choosing from the chip designs on the Pareto front, a user can obtain high capture efficiency without exceeding the flow resistance constraints of their application.

Molecular Determinants and Signaling Effects of PKA RIα Phase Separation.

Spatiotemporal regulation of intracellular signaling molecules, such as the 3',5'-cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA), ensures the specific execution of various cellular functions. Liquid-liquid phase separation (LLPS) of the ubiquitously expressed PKA regulatory subunit RIα was recently identified as a major driver of cAMP compartmentation and signaling specificity. However, the molecular determinants of RIα LLPS remain unclear. Here, we reveal that two separate dimerization interfaces combined with the cAMP-induced release of the PKA catalytic subunit (PKA-C) from the pseudosubstrate inhibitory sequence are required to drive RIα condensate formation in cytosol, which is antagonized by docking to A-kinase anchoring proteins. Strikingly, we find that the RIα pseudosubstrate region is critically involved in the formation of a non-canonical R:C complex, which serves to maintain low basal PKA activity in the cytosol by enabling the recruitment of active PKA-C to RIα condensates. Our results suggest that RIα LLPS not only facilitates cAMP compartmentation but also spatially restrains active PKA-C, thus highlighting the functional versatility of biomolecular condensates in driving signaling specificity.

Proteogenomic identification of Hepatitis B virus (HBV) genotype-specific HLA-I restricted peptides from HBV-positive patient liver tissues.

The presentation of virus-derived peptides by HLA class I molecules on the surface of an infected cell and the recognition of these HLA-peptide complexes by, and subsequent activation of, CD8+ cytotoxic T cells provides an important mechanism for immune protection against viruses. Recent advances in proteogenomics have allowed researchers to discover a growing number of unique HLA-restricted viral peptides, resulting in a rapidly expanding repertoire of targets for immunotherapeutics (i.e. bispecific antibodies, engineered T-cell receptors (TCRs), chimeric antigen receptor T-cells (CAR-Ts)) to infected tissues. However, genomic variability between viral strains, such as Hepatitis-B virus (HBV), in combination with differences in patient HLA alleles, make it difficult to develop therapeutics against these targets. To address this challenge, we developed a novel proteogenomics approach for generating patient-specific databases that enable the identification of viral peptides based on the viral transcriptomes sequenced from individual patient liver samples. We also utilized DNA sequencing of patient samples to identify HLA genotypes and assist in target selection. Liver samples from 48 HBV infected patients, primarily from Asia, were examined to reconstruct patient-specific HBV genomes, identify regions within the human chromosomes targeted by HBV integrations and obtain a comprehensive view of HBV peptide epitopes using our HLA class-I (HLA-I) immunopeptidomics discovery platform. Two previously reported HLA associated HBV-derived peptides, HLA-A02 binder FLLTRILTI (S194-202) from the large surface antigen and HLA-A11 binder STLPETTVVRR (C141-151) from the capsid protein were validated by our discovery platform, but both were detected at very low frequencies. In addition, we identified and validated, using heavy peptide analogues, novel strain-specific HBV-HLA associated peptides, such as GSLPQEHIVQK (P606-616) and variants. Overall, our novel approach can guide the development of bispecific antibody, TCR-T, or CAR-T based therapeutics for the treatment of HBV-related HCC and inform vaccine development.

Pirtobrutinib inhibits wild-type and mutant Bruton's tyrosine kinase-mediated signaling in chronic lymphocytic leukemia.

Pirtobrutinib (LOXO-305), a reversible inhibitor of Bruton's tyrosine kinase (BTK), was designed as an alternative strategy to treat ibrutinib-resistant disease that develops due to C481 kinase domain mutations. The clinical activity of pirtobrutinib has been demonstrated in CLL, but the mechanism of action has not been investigated. We evaluated pirtobrutinib in 4 model systems: first, MEC-1, a CLL cell line overexpressing BTKWT, BTKC481S, or BTKC481R; second, murine models driven by MEC-1 overexpressing BTKWT or BTKC481S; third, in vitro incubations of primary CLL cells; and finally, CLL patients during pirtobrutinib therapy (NCT03740529, ClinicalTrials.gov). Pirtobrutinib inhibited BTK activation as well as downstream signaling in MEC-1 isogenic cells overexpressing BTKWT, BTKC481S, or BTKC481R. In mice, overall survival was short due to aggressive disease. Pirtobrutinib treatment for 2 weeks led to reduction of spleen and liver weight in BTKWT and BTKC481S cells, respectively. In vitro incubations of CLL cells harboring wild-type or mutant BTK had inhibition of the BCR pathway with either ibrutinib or pirtobrutinib treatment. Pirtobrutinib therapy resulted in inhibition of BTK phosphorylation and downstream signaling initially in all cases irrespective of their BTK profile, but these effects started to revert in cases with other BCR pathway mutations such as PLCG2 or PLEKHG5. Levels of CCL3 and CCL4 in plasma were marginally higher in patients with mutated BTK; however, there was a bimodal distribution. Both chemokines were decreased at early time points and mimicked BCR pathway protein changes. Collectively, these results demonstrate that pirtobrutinib is an effective BTK inhibitor for CLL harboring wild-type or mutant BTK as observed by changes in CCL3 and CCL4 biomarkers and suggest that alterations in BCR pathway signaling are the mechanism for its clinical effects. Long-term evaluation is needed for BTK gatekeeper residue variation along with pathologic kinase substitution or mutations in other proteins in the BCR pathway.

Synergy of Venetoclax and 8-Chloro-Adenosine in AML: The Interplay of rRNA Inhibition and Fatty Acid Metabolism.

It is known that 8-chloro-adenosine (8-Cl-Ado) is a novel RNA-directed nucleoside analog that targets leukemic stem cells (LSCs). In a phase I clinical trial with 8-Cl-Ado in patients with refractory or relapsed (R/R) AML, we observed encouraging but short-lived clinical responses, likely due to intrinsic mechanisms of LSC resistance. LSC homeostasis depends on amino acid-driven and/or fatty acid oxidation (FAO)-driven oxidative phosphorylation (OXPHOS) for survival. We recently reported that 8-Cl-Ado and the BCL-2-selective inhibitor venetoclax (VEN) synergistically inhibit FAO and OXPHOS in LSCs, thereby suppressing acute myeloid leukemia (AML) growth in vitro and in vivo. Herein, we report that 8-Cl-Ado inhibits ribosomal RNA (rRNA) synthesis through the downregulation of transcription initiation factor TIF-IA that is associated with increasing levels of p53. Paradoxically, 8-Cl-Ado-induced p53 increased FAO and OXPHOS, thereby self-limiting the activity of 8-Cl-Ado on LSCs. Since VEN inhibits amino acid-driven OXPHOS, the addition of VEN significantly enhanced the activity of 8-Cl-Ado by counteracting the self-limiting effect of p53 on FAO and OXPHOS. Overall, our results indicate that VEN and 8-Cl-Ado can cooperate in targeting rRNA synthesis and OXPHOS and in decreasing the survival of the LSC-enriched cell population, suggesting the VEN/8-Cl-Ado regimen as a promising therapeutic approach for patients with R/R AML.

The role of p53 and p21 on 8-chloro-adenosine-induced cellular response.

8-Chloro-adenosine (8-Cl-Ado) is currently in phase I clinical trial. Activation of p53 and transactivation of p21 regulate cell fate after genotoxic insult. Using HCT-116-isogenic-cell-lines, we evaluated the role of p53/p21 after 8-Cl-Ado-mediated response. Following 30 µM 8-Cl-Ado treatment, RNA synthesis was inhibited, p53 protein was stabilized, and p21 expression was activated. None of the cell types were arrested in G1/S phase, however, cells lacking p53 were blocked in G2/M. These cells had the least increase in apoptotic cells, although clonogenic survival demonstrated equal inhibition in all 4 cell types. Collectively, irrespective of p53 and p21 status, 8-Cl-Ado-induced cytotoxicity was similar.

Carbodiimide-Driven Dimerization and Self-Assembly of Artificial, Ribose-Based Amphiphiles.

The aqueous self-assembly of amphiphiles into aggregates such as micelles and vesicles has been widely investigated over the past decades with applications ranging from materials science to drug delivery. The combination of characteristic properties of nucleic acids and amphiphiles is of substantial interest to mimic biological self-organization and compartmentalization. Herein, we present ribose- and ribonucleotide-based amphiphiles and investigate their self-assembly as well as their fundamental reactivity. We found that various types of aggregates are formed, ranging in size from nanometers to micrometers and all amphiphiles exhibit aggregation-induced emission (AIE) in solution as well as in the solid state. We also observed that the addition of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) leads to rapid and selective dimerization of the amphiphiles into pyrophosphates, which decreases the critical aggregation concentration (CAC) by a factor of 25 when compared to the monomers. Since the propensity for amphiphile dimerization is correlated with their tendency to self-assemble, our results may be relevant for the formation of rudimentary compartments under prebiotic conditions.

International Microsurgery Club Webinar Series-Bridging the Knowledge Gap during the COVID-19 Pandemic.

BACKGROUND: The impact of the coronavirus disease 2019 (COVID-19) outbreak shut down most conferences. To minimalize the influence, virtual meetings sprang up subsequently. International Microsurgery Club (IMC), as one of the largest professionals-only online microsurgery education groups worldwide, began to host regular weekend webinars during the pandemic to fill the knowledge gap. This study aims to discuss how webinars have fundamentally changed the way knowledge is delivered and exchanged. METHODS: From February 29, 2020 to March 14, 2021, 103 IMC webinars were reviewed and analyzed in detail to determine the use, benefit, and effect. A comparison between webinars hosted by the different societies was made as well. A questionnaire survey focusing on attendees' behavior, attitude, and using habit about webinars was also made. RESULTS: As for the 103 IMC webinar events, the peak participants were 112.3 people in average. The members requesting to join IMC abruptly increased during the pandemic, and the group activity increased dramatically. From the questionnaire (n = 68), the satisfaction level was high (8.88 ± 1.18/10). The respondents were most satisfied with the good quality of the speakers (73.5%). Not only hosts our webinar series but IMC also serves as the platform that welcomes webinars from other societies to share their information. In September 2020, International Microsurgery Webinar League was established via the significant webinar hosts, with more than 300 recorded webinar talks connected successfully. CONCLUSION: As the knowledge revolution driven by COVID-19 will continue, IMC will keep playing an essential role in exploring new and emerging opportunities to improve knowledge dissemination worldwide beyond the space-time boundary.

Establishment and Evaluation of a Large Contact-Tracing and Case Investigation Virtual Training Academy.

During the COVID-19 pandemic, the Virtual Training Academy (VTA) was established to rapidly develop a contact-tracing workforce for California. Through June 2021, more than 10 000 trainees enrolled in a contact-tracing or case investigation course at the VTA. To evaluate program effectiveness, we analyzed trainee pre- and postassessment results using the Wilcoxon signed-rank test. There was a statistically significant (P < .001) improvement in knowledge and self-perceived skills after course completion, indicating success in training a competent contact-tracing workforce. (Am J Public Health. 2021;111(11):1934-1938. https://doi.org/10.2105/AJPH.2021.306468).