The First Months of Life of ChatGPT and Its Impact in Healthcare: A Bibliometric Analysis of the Current Literature

We aimed to evaluate current trends and future directions in the field of AI research since ChatGPT was launched. We performed a bibliometric analysis of the literature published during the first 7 months of the life of ChatGPT since its introduction, updated to July 1st, 2023. Seven hundred and twenty-four (724) articles were retrieved. This analysis highlights a significant increase in publications exploring ChatGPT use across various medical disciplines, indicating its expanding relevance in healthcare. A decline proportion of studies focusing on ethical considerations was observed. Simultaneously, there was a steady increase in studies focused on the exploration of possible applications of ChatGPT. As ChatGPT applications continue to expand, ongoing vigilance and collaborative efforts to optimize ChatGPT performance are essential in harnessing the benefits while mitigating the risks of AI use in healthcare.

Enhancing classical swine fever virus identification: the advantages of Field-LAMP testing

Classical swine fever virus (CSFV) identification has witnessed significant advancements with the development of rapid reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assays. However, conventional RT-LAMP assays for CSFV diagnosis are hindered by a laborious RNA extraction step. Moreover, the need for thermal incubators and expensive micropipettes has limited their application in field settings. Addressing these challenges, our study presents a groundbreaking solution-an electro-free and point-of-care (POC) tool known as the field-LAMP assay-for the rapid clinical detection of CSFV. By eliminating the RNA extraction requirement, advancing the colorimetric read-out and lyophilized reaction reagents, our field-LAMP assay streamlines the diagnostic process, saving valuable time and effort. This novel approach also overcomes the dependency on electric-dependent thermal incubators and expensive micropipettes, making it practical and accessible for use in the field. The successful development of the field-LAMP assay marks a significant milestone in CSFV detection. This electro-free and POC tool offers several advantages, including its ability to deliver rapid results without compromising accuracy, facilitating prompt response and containment measures.

Consulting the Digital Doctor: Google Versus ChatGPT as Sources of Information on Breast Implant-Associated Anaplastic Large Cell Lymphoma and Breast Implant Illness

BACKGROUND

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare complication associated with the use of breast implants. Breast implant illness (BII) is another potentially concerning issue related to breast implants. This study aims to assess the quality of ChatGPT as a potential source of patient education by comparing the answers to frequently asked questions on BIA-ALCL and BII provided by ChatGPT and Google.

METHODS

The Google and ChatGPT answers to the 10 most frequently asked questions on the search terms "breast implant associated anaplastic large cell lymphoma" and "breast implant illness" were recorded. Five blinded breast plastic surgeons were then asked to grade the quality of the answers according to the Global Quality Score (GQS). A Wilcoxon paired t-test was performed to evaluate the difference in GQS ratings for Google and ChatGPT answers. The sources provided by Google and ChatGPT were also categorized and assessed.

RESULTS

In a comparison of answers provided by Google and ChatGPT on BIA-ALCL and BII, ChatGPT significantly outperformed Google. For BIA-ALCL, Google's average score was 2.72 ± 1.44, whereas ChatGPT scored an average of 4.18 ± 1.04 (p < 0.01). For BII, Google's average score was 2.66 ± 1.24, while ChatGPT scored an average of 4.28 ± 0.97 (p < 0.01). The superiority of ChatGPT's responses was attributed to their comprehensive nature and recognition of existing knowledge gaps. However, some of ChatGPT's answers had inaccessible sources.

CONCLUSION

ChatGPT outperforms Google in providing high-quality answers to commonly asked questions on BIA-ALCL and BII, highlighting the potential of AI technologies in patient education.

LEVEL OF EVIDENCE

Level III, comparative study LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A 15-Year Experience With Total Anomalous Pulmonary Venous Connection in Vietnam

BACKGROUND

This article aims to demonstrate the morphology of 261 total anomalous pulmonary venous connection (TAPVC) cases operated at Children's Hospital 1 with in-hospital mortality of 19.5% (51/261).

METHODS

All the surgical protocols of TAPVC cases repaired between 2008 and June 2023 were reviewed. The descriptions of TAPVC were based on operative findings by surgeons.

RESULTS

A total of 261 TAPVC patients were operated, including 124 (47.5%) supra, 83 (31.8%) intra, 41 (15.7%) infra, and 13 (5%) mixed cases. The in-hospital mortality was 19.5% (51/261). Fifteen cases are associated with other anomalies of the heart. Four subtypes of 124 supra TAPVC were found, with 42 (33.9%) obstructed cases. The standard was all pulmonary veins (PVs) forming a common vein (CV) and draining into the innominate veins, then going to the superior vena cava (SVC) (100/124, 80.6%). Eleven supra TAPVC cases were vascular vise type. Ten cases had the vertical vein running from the right of the CV and draining directly into the SVC. Of 83 intracardiac TAPVCs with 9 (10.8%) obstructed cases, the most common was all PVs draining directly into the coronary sinus (60/83, 72.3%). The second was all PVs draining directly into the right atrium (RA) via separated ostia or forming a CV before entering the RA (17/83, 20.5%). Also, there were three cases with rare variants and 100% obstruction when the diagnosis was explored. The in-hospital mortality of intracardiac type was 13.3% (11/83) 41 infra TAPVC with obstructed rate of 61% (25/41) and in-hospital mortality of 29.3% (12/41). Thirteen mixed TAPVCs were repaired, with most cases having three PVs forming a CV.

CONCLUSION

This article provides valuable information about the morphology of TAPVC types in Asian patients.

Online patient education in body contouring: A comparison between Google and ChatGPT

Appropriate patient education and preparation prior to surgery represent a fundamental step in managing expectations, avoiding unnecessary encounters and eventually achieving optimal outcomes. Thus, the objective of this study is to evaluate ChatGPT's potential as a viable source for patient education by comparing its responses and provided references to frequently asked questions on body contouring, with Google's. A Google search was conducted on July 15th, 2023, using the search term "body contouring surgery". The first 15 questions under the "People also ask" section and answers provided by Google were recorded. The 15 questions were then asked to ChatGPT-3.5. Four plastic surgeons evaluated the answers from 1 to 5 according to the Global Quality Scale. The mean score for responses given by Google was 2.55 ± 1.29, indicating poor quality but some information present, of very limited use to patients. The mean score for responses produced by ChatGPT was 4.38 ± 0.67, suggesting that the content was of good quality, useful to patients, and encompassed the most important topics. The difference was statistically significant (p = 0.001). Deficiencies in providing references represent one of the most evident weaknesses of ChatGPT. However, ChatGPT did not appear to spread misinformation, and the content of the generated responses was deemed of good quality and useful to patients. The integration of AI technology as a source for patient education has the potential to optimize patient queries on body contouring questions.

Evolutionary degeneration of septins into pseudoGTPases: impacts on a hetero-oligomeric assembly interface

The septin family of eukaryotic proteins comprises distinct classes of sequence-related monomers that associate in a defined order into linear hetero-oligomers, which are capable of polymerizing into cytoskeletal filaments. Like actin and ⍺ and β tubulin, most septin monomers require binding of a nucleotide at a monomer-monomer interface (the septin "G" interface) for assembly into higher-order structures. Like ⍺ and β tubulin, where GTP is bound by both subunits but only the GTP at the ⍺-β interface is subject to hydrolysis, the capacity of certain septin monomers to hydrolyze their bound GTP has been lost during evolution. Thus, within septin hetero-oligomers and filaments, certain monomers remain permanently GTP-bound. Unlike tubulins, loss of septin GTPase activity-creating septin "pseudoGTPases"-occurred multiple times in independent evolutionary trajectories, accompanied in some cases by non-conservative substitutions in highly conserved residues in the nucleotide-binding pocket. Here, we used recent septin crystal structures, AlphaFold-generated models, phylogenetics and in silico nucleotide docking to investigate how in some organisms the septin G interface evolved to accommodate changes in nucleotide occupancy. Our analysis suggests that yeast septin monomers expressed only during meiosis and sporulation, when GTP is scarce, are evolving rapidly and might not bind GTP or GDP. Moreover, the G dimerization partners of these sporulation-specific septins appear to carry compensatory changes in residues that form contacts at the G interface to help retain stability despite the absence of bound GDP or GTP in the facing subunit. During septin evolution in nematodes, apparent loss of GTPase activity was also accompanied by changes in predicted G interface contacts. Overall, our observations support the conclusion that the primary function of nucleotide binding and hydrolysis by septins is to ensure formation of G interfaces that impose the proper subunit-subunit order within the hetero-oligomer.

Biomedical doctoral students' research practices when facing dilemmas: two vignette-based randomized control trials

Our aim was to describe the research practices of doctoral students facing a dilemma to research integrity and to assess the impact of inappropriate research environments, i.e. exposure to (a) a post-doctoral researcher who committed a Detrimental Research Practice (DRP) in a similar situation and (b) a supervisor who did not oppose the DRP. We conducted two 2-arm, parallel-group randomized controlled trials. We created 10 vignettes describing a realistic dilemma with two alternative courses of action (good practice versus DRP). 630 PhD students were randomized through an online system to a vignette (a) with (n = 151) or without (n = 164) exposure to a post-doctoral researcher; (b) with (n = 155) or without (n = 160) exposure to a supervisor. The primary outcome was a score from - 5 to + 5, where positive scores indicated the choice of DRP and negative scores indicated good practice. Overall, 37% of unexposed participants chose to commit DRP with important variation across vignettes (minimum 10%; maximum 66%). The mean difference [95%CI] was 0.17 [- 0.65 to 0.99;], p = 0.65 when exposed to the post-doctoral researcher, and 0.79 [- 0.38; 1.94], p = 0.16, when exposed to the supervisor. In conclusion, we did not find evidence of an impact of postdoctoral researchers and supervisors on student research practices.Trial registration: NCT04263805, NCT04263506 (registration date 11 February 2020).

Perceptual Barriers to Becoming a Plastic Surgeon among Underrepresented Medical Students

Background

The field of plastic surgery has experienced difficulty increasing diversity among trainees, despite significant efforts. Barriers to recruitment of underrepresented in medicine (URM) students are poorly understood. This study assesses URM students' exposure to plastic surgery, access to mentors and research opportunities, and the importance of diversity in the field.

Methods

A survey was designed and distributed to members of the Student National Medical Association over 3 months. Survey data were collected using Qualtrics and descriptive statistics, and logistical regressions were performed using SAS.

Results

Of the 136 respondents, 75.0% identified as Black (n = 102/136), and 57.4% (n = 66/115) reported a plastic surgery program at their home institution. Of the total respondents, 97.7% (n = 127/130) were concerned about racial representation in plastic surgery, and 44.9% (n = 53/114) would be more likely to apply if there were better URM representation. Most respondents disagreed that there was local (73.4%, n = 58/79) or national (79.2%, n = 57/72) interest in URM recruitment. Students whose plastic surgery programs had outreach initiatives were more likely to have attending (OR 11.7, P < 0.05) or resident mentors (OR 3.0 P < 0.05) and access to research opportunities (OR 4.3, P < 0.05).

Conclusions

URM students feel there is an evident lack of interest in recruiting URM applicants in plastic surgery. Programs with outreach initiatives are more likely to provide URM students access to mentorship and research opportunities, allowing students to make informed decisions about pursuing plastic surgery.

Association of Labor Epidural Analgesia, Oxytocin Exposure, and Risk of Autism Spectrum Disorders in Children

Importance

Maternal labor epidural analgesia (LEA) and oxytocin use for labor and delivery have been reported to be associated with child autism spectrum disorders (ASD). However, it remains unclear whether these 2 common medications used during labor and delivery have synergistic associations with ASD risk in children.

Objective

To assess the independent associations of LEA and oxytocin during labor and delivery with ASD, as well as outcome modification associated with the concurrent use of both interventions.

Design, Setting, and Participants

Data for this cohort study included 205 994 singleton births with vaginal deliveries in a single integrated health care system in Southern California from calendar years 2008 to 2017. Children were followed up to December 31, 2021. Data on use of LEA and oxytocin, covariates, and ASD outcome in children were obtained from electronic medical records. Cox proportional hazards regression was used to estimate the hazard ratios (HRs) adjusting for covariates.

Exposures

Labor epidural analgesia and/or oxytocin use during labor and delivery.

Main Outcomes and Measures

A child's clinical diagnosis of ASD during follow-up and at age of diagnosis.

Results

Among the cohort, 153 880 children (74.7%) were exposed to maternal LEA and 117 808 children (57.2%) were exposed to oxytocin during labor and delivery. The population of children was approximately half boys and half girls. The median (IQR) age of the mothers was 30.8 (26.8-34.5) years for those not exposed to LEA, 30.0 (25.9-33.8) years for those exposed to LEA, 30.4 (26.5-34.1) years for those unexposed to oxytocin, and 30.0 (25.9-33.9) years for those exposed to oxytocin during labor and delivery. A total of 5146 children (2.5%) had ASD diagnosed during follow-up. Oxytocin exposure was higher among LEA-exposed (67.7%) than -unexposed (26.1%) children. The ASD risk associated with LEA was independent of oxytocin exposure (HR, 1.28; 95% CI, 1.18-1.38); however, the ASD risk associated with oxytocin was not significant after adjusting for LEA exposure (HR, 1.05; 95% CI, 0.99-1.12). A significant interaction of LEA and oxytocin on child ASD risk was found (P = .02 for interaction). Compared with no exposure, HRs were 1.20 (95% CI, 1.09-1.32) for LEA alone, 1.30 (95% CI, 1.20-1.42) for both LEA and oxytocin, and 0.90 (95% CI, 0.78-1.04) for oxytocin alone.

Conclusions and Relevance

The findings of this cohort study suggest an association between maternal LEA and ASD risk in children, and the risk appeared to be further increased if oxytocin was also administered. Oxytocin exposure without LEA exposure was not associated with ASD risk in children. These findings must be interpreted with caution. Further studies are needed to replicate or refute the study results and examine biological plausibility.

Veiled Harm: Impacts of Microaggressions on Psychological Safety and Physician Burnout

Microaggression is widespread in the health care industry and occurs in every health care delivery setting. It comes in many forms, from subtle to obvious, unconscious to conscious, and verbal to behavioral. Women and minority groups (eg, race/ethnicity, age, gender, sexual orientation) are often marginalized during medical training and subsequent clinical practice. These contribute to the development of psychologically unsafe working environments and widespread physician burnout. Physicians experiencing burnout who work in unsafe psychological environments impact the safety and quality of patient care. In turn, these conditions impose high costs on the health care system and organizations. Microaggressions and psychological unsafe work environments are intricately related and mutually enhanced. Therefore, addressing both simultaneously is a good business practice and a responsibility for any health care organization. Additionally, addressing them can reduce physician burnout, decrease physician turnover, and improve the quality of patient care. To counter microaggression and psychological unsafe, it takes conviction, initiative, and sustainable efforts from individuals, bystanders, organizations, and government agencies.

Novel chromobox 2 inhibitory peptide decreases tumor progression

BACKGROUND

The Polycomb Repressor Complex 1 (PRC1) is an epigenetic regulator of differentiation and development, consisting of multiple subunits including RING1, BMI1, and Chromobox. The composition of PRC1 dictates its function and aberrant expression of specific subunits contributes to several diseases including cancer. Specifically, the reader protein Chromobox2 (CBX2) recognizes the repressive modifications including histone H3 lysine 27 tri-methylation (H3K27me3) and H3 lysine 9 dimethylation (H3K9me2). CBX2 is overexpressed in several cancers compared to the non-transformed cell counterparts, it promotes both cancer progression and chemotherapy resistance. Thus, inhibiting the reader function of CBX2 is an attractive and unique anti-cancer approach.

RESEARCH DESIGN & METHODS

Compared with other CBX family members, CBX2 has a unique A/T-hook DNA binding domain that is juxtaposed to the chromodomain (CD). Using a computational approach, we constructed a homology model of CBX2 encompassing the CD and A/T hook domain. We used the model as a basis for peptide design and identified blocking peptides that are predicted to directly bind the CD and A/T-hook regions of CBX2. These peptides were tested in vitro and in vivo models.

CONCLUSION

The CBX2 blocking peptide significantly inhibited both 2D and 3D growth of ovarian cancer cells, downregulated a CBX2 target gene, and blunted tumor growth in vivo.

Individual-level permethrin exposure biomarkers in U.S. army soldiers: comparison of two treatment formulations for military uniforms

BACKGROUND

Evidence suggests that wearing permethrin-treated military uniforms is not associated with current adverse health conditions. However, exposure through this route results in permethrin biomarker concentrations considerably higher than those in the U.S.

POPULATION

The U.S. Army is exploring different methods of uniform treatment that reduce exposure while maintaining effective protection from insect vector-borne diseases.

OBJECTIVE

To compare permethrin exposure when wearing two types of permethrin-treated military uniforms.

METHODS

Eight male soldiers participated in a 32-day crossover design study to compare permethrin exposure when wearing the current Army uniform (CurrU) and a uniform with a new applied fabric treatment (NewU). Each soldier wore the uniforms for designated 8 h/day time periods over 3 consecutive days separated by a 'wash-out' week of no exposure. Permethrin exposure was assessed from the urinary concentrations of 3-phenoxybenzoic acid (3-PBA) and of the sum of cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (∑DCCA). Estimated dose was determined based on ∑DCCA concentrations.

RESULTS

Permethrin exposure biomarkers were 21% (3-PBA, p = 0.025) and 35% (∑DCCA, p < 0.001) lower when wearing the NewU compared to the CurrU; the dose was 33% lower (p = 0.05).

SIGNIFICANCE

Findings suggest the new treatment reduces human permethrin exposure biomarkers resulting from wearing-treated military uniforms.

Standard Fixed Enoxaparin Dosing for Venous Thromboembolism Prophylaxis Leads to Low Peak Anti-Factor Xa Levels in Both Head and Neck and Breast Free Flap Patients

INTRODUCTION

 Venous thromboembolism (VTE) is a serious complication, particularly in cancer patients undergoing free flap reconstruction. Subcutaneous enoxaparin is the conventional prophylaxis for VTE prevention, and serum anti-factor Xa (afXa) levels are being increasingly used to monitor enoxaparin activity. In this study, free flap patients receiving standard enoxaparin prophylaxis were prospectively followed to investigate postoperative afXa levels and 90-day VTE and bleeding-related complications.

METHODS

 Patients undergoing free tissue transfer during an 8-month period were identified and prospectively followed. Patients received standard fixed enoxaparin dosing at 30 mg twice daily in head and neck (H&N) and 40 mg daily in breast reconstructions. Target peak prophylactic afXa range was 0.2 to 0.5 IU/mL. The primary outcome was the occurrence of 90-day postoperative VTE- and bleeding-related events. Independent predictors of afXa level and VTE incidence were analyzed for patients that met the inclusion criteria.

RESULTS

 Seventy-eight patients were prospectively followed. Four (5.1%) were diagnosed with VTE, and six (7.7%) experienced bleeding-related complications. The mean afXa levels in both VTE patients and bleeding patients were subprophylactic (0.13 ± 0.09 and 0.11 ± 0.07 IU/mL, respectively). Forty-six patients (21 breast, 25 H&N) had valid postoperative peak steady-state afXa levels. Among these, 15 (33%) patients achieved the target prophylactic range: 5 (33%) H&N and 10 (67%) breast patients. The mean afXa level for H&N patients was significantly lower than for breast patients (p = 0.0021). Patient total body weight was the sole negative predictor of afXa level (R ² = 0.47, p < 0.0001).

CONCLUSION

 Standard fixed enoxaparin dosing for postoperative VTE prophylaxis does not achieve target afXa levels for the majority of our free flap patients. H&N patients appear to be a particularly high-risk group that may require a more personalized and aggressive approach. Total body weight is the sole negative predictor of afXa level, supporting a role for weight-based enoxaparin dosing.

Transgender Mastectomy: Incidence of High-Risk Pathologic Findings and the Need for Postoperative Cancer Surveillance

BACKGROUND

Chest masculinization surgeries are one of the most common gender-affirming procedures performed. There is a need for better understanding of the risk of breast cancer and postsurgical screening in female to male (FtM) individuals. This study aimed to evaluate the incidence of high-risk pathologic findings in FtM transgender patients undergoing gender-affirming chest reconstructive surgery.

METHODS

Medical records were reviewed from all FtM patients undergoing gender-affirming chest reconstructive surgery from January 2010 to February 2021 by 3 plastic surgeons at the University of Pittsburgh Medical Center. Relative risk of malignant progression was used to stratify pathologic data. Subsequent management of atypical, in situ, and invasive pathology were recorded.

RESULTS

A total of 318 patients were included in this study; the average age at surgery was 24.6 ± 8.1 years. Eighty-six patients (27%) had a family history of breast and/or ovarian cancer. Overall, 21 patients (6.6%) had some increased risk of breast cancer: 17 (5.3%) had proliferative lesions, mean age 38.2 ± 12.4 years; 2 had atypical ductal hyperplasia, ages 33.4 and 38.3 years; and 2 had invasive ductal carcinoma, ages 35.4 and 40.6 years.

CONCLUSIONS

In this study, we found that 6.6% of FtM transgender patients undergoing top surgery had an elevated risk of breast cancer, with 1.2% of patients having a greater than 2 times risk of breast cancer. These results highlight the importance of appropriate preoperative screening as well as pathological analysis of surgical specimens to help guide clinical care. The authors advocate for a thorough breast cancer risk assessment before surgery for all patients, as well as using pathologic findings to guide postoperative cancer screening and follow-up.

Functional group divergence and the structural basis of acridine photocatalysis revealed by direct decarboxysulfonylation

The reactivity of the sulfonyl group varies dramatically from nucleophilic sulfinates through chemically robust sulfones to electrophilic sulfonyl halides-a feature that has been used extensively in medicinal chemistry, synthesis, and materials science, especially as bioisosteric replacements and structural analogs of carboxylic acids and other carbonyls. Despite the great synthetic potential of the carboxylic to sulfonyl functional group interconversions, a method that can convert carboxylic acids directly to sulfones, sulfinates and sulfonyl halides has remained out of reach. We report herein the development of a photocatalytic system that for the first time enables direct decarboxylative conversion of carboxylic acids to sulfones and sulfinates, as well as sulfonyl chlorides and fluorides in one step and in a multicomponent fashion. A mechanistic study prompted by the development of the new method revealed the key structural features of the acridine photocatalysts that facilitate the decarboxylative transformations and provided an informative and predictive multivariate linear regression model that quantitatively relates the structural features with the photocatalytic activity.

Increasing sample diversity in psychiatric genetics - Introducing a new cohort of patients with schizophrenia and controls from Vietnam - Results from a pilot study

OBJECTIVES

Genome-Wide Association Studies (GWAS) of Schizophrenia (SCZ) have provided new biological insights; however, most cohorts are of European ancestry. As a result, derived polygenic risk scores (PRS) show decreased predictive power when applied to populations of different ancestries. We aimed to assess the feasibility of a large-scale data collection in Hanoi, Vietnam, contribute to international efforts to diversify ancestry in SCZ genetic research and examine the transferability of SCZ-PRS to individuals of Vietnamese Kinh ancestry.

METHODS

In a pilot study, 368 individuals (including 190 SCZ cases) were recruited at the Hanoi Medical University's associated psychiatric hospitals and outpatient facilities. Data collection included sociodemographic data, baseline clinical data, clinical interviews assessing symptom severity and genome-wide SNP genotyping. SCZ-PRS were generated using different training data sets: (i) European, (ii) East-Asian and (iii) trans-ancestry GWAS summary statistics from the latest SCZ GWAS meta-analysis.

RESULTS

SCZ-PRS significantly predicted case status in Vietnamese individuals using mixed-ancestry (R² liability = 4.9%, p = 6.83 × 10^-8), East-Asian (R² liability = 4.5%, p = 2.73 × 10^-7) and European (R² liability = 3.8%, p = 1.79 × 10^-6) discovery samples.

DISCUSSION

Our results corroborate previous findings of reduced PRS predictive power across populations, highlighting the importance of ancestral diversity in GWA studies.

Evaluation of Undiagnosed HIV Estimates Computed from the CD4 Depletion Model in a Rural, Medium-low HIV Prevalence State

The CD4 depletion model estimates diagnosis delays by approximating infection date from CD4 T-cell count at diagnosis, and back-calculation can compute the proportion of undiagnosed PLWHA. The model assumes the immigration of PLWHA to the U.S. is negligible and counts as a transmission event, which may be impractical outside high prevalence states. Duration of U.S. residency among foreign-born PLWHA and diagnosis delays were compared. The impact on estimates of undiagnosed PLWHA was tested through simulation with different proportions of foreign-born people assumed to have acquired HIV abroad. In 67% of foreign-born people, the mean (SD) years of delay (9.9 (6.3)) exceeded the duration of U.S. residency (2.0 (1.9)). Additionally, inaccuracies in the estimates for proportions of undiagnosed PLWHA were pronounced when foreign-born people who acquired HIV abroad comprised 30% of diagnoses. The CD4 model inadvertently misclassified some diagnoses as in-state transmission events. Consequently, simulated results demonstrated inaccuracies and unstable calculations.

Virtual Subinternship in Plastic Surgery: The Start of a New Era in Surgical Education?

Supplemental Digital Content is available in the text.

Feasibility, safety and long term outcomes of complex left main bifurcation treatment using the nano inverted t stenting: a multicentre registry

Background

The role of double stenting techniques in distal bifurcation left main (LM) disease has gaining interest over the latest years.

Purpose

We present the 3-year multicentre registry outcomes of dual stenting using ultra-thin strut stents and the Nano Inverted-T (NIT) technique in complex unprotected true LM bifurcation disease.

Methods

We analysed the procedural and medical data of consecutive patients enrolled between 1st January 2014 and 1st December 2019 in a multicentre registry for complex LM bifurcation disease treated with the double stenting technique called NIT due contraindications and/or refusal to surgical treatment. Target lesion failure (TLF) was defined as the composite of cardiovascular death, target-vessel MI (TVMI) and clinically driven target lesion revascularization (TLR).

Results

Among two hundred-ninety-five patients (138 males, mean age 70.3±12.8 years), post-operative success was achieved in 100% of cases. Contrast volume, procedural time, and radiation exposure were 139.2±23.4 ml, 15.3±4.9 min, and 1080±1034 cGy/m2 (Figure), respectively. At a mean follow-up of 39.5±0.6 months TLF rate was 6.1% (n=18) while TLR and cardiovascular mortality rates were 3.0 (n=9) and 2.6% (n=8), respectively. Clinically driven angiographic follow-up was available in 26.4% of patients at a mean time from the procedure of 7.5±0.4 months. Clinically restenosis rate was 3.3%.

Conclusions

Revascularization of complex LM bifurcation disease using the NIT double stenting technique resulted feasible and safe with a low incidence of TLF, excellent survival rate and no stent thrombosis. Figure 1.The NIT technique is based on the use of ultra-thin strut (≤80 micron) stents and double stenting starting with side branch stenting frst. The side branch stent is precisely positioned with one possibly only strut protruding into the main vessel which is balloon crushed before the implantation of the main branch stenting. The Proximal optimization technique (POT)–snuggle kissing–POT sequence is mandatory to ensure the coverage of the side branch ostium by both side branch and main branch stents. Snuggle kissing was performed placing the LCX balloon with the proximal marker at the middle rather than at the proximal marker of the LM-LAD balloon, in order to minimize the elliptical deformation of the LM stent.

Funding Acknowledgement

Type of funding sources: None. Figure 1

The Impact of Fellowship Training in Academic Plastic Surgery

BACKGROUND

The competitive nature of an academic plastic surgery career has contributed to an increase in sub-specialization. The aim of this study is to assess the benefits of subspecialty fellowship training to pursue a career in academic plastic surgery.

METHODS

A cross-sectional study was conducted of all current academic plastic surgeons (APSs) participating in Accreditation Council for Graduate Medical Education-certified residency programs. Online faculty website listings were used to collect their demographics, training and practice characteristics, academic rank and leadership positions, and research productivity.

RESULTS

A total of 927 APSs met the inclusion criteria, of which 70.2% had undergone fellowship training, with an overall significant increase in fellowship-trained surgeons within the last 10 years (odds ratio [OR], 1.66; P = 0.0005). Hand training was the most common fellowship (35.6%), followed by craniofacial (32.0%) and microsurgery (28.1%). Fellowship training was more prevalent among younger (48.7 vs 53.5 years, P < 0.0001), White (67.8%), and non-White (77.4%, P = 0.0058) APSs who had received either integrated (67.1%) or independent (81.8%, P < 0.0001) plastic surgery training and are currently working in a department (OR, 1.44; P = 0.028). Fellowship training was shown to influence academic rank (associate professor: OR, 1.68 [P = 0.0073]; full professor: OR, 0.58 [P = 0.0008]), leadership position (fellowship director OR, 10.09; P < 0.0001) and research productivity (publications: 26 vs 16.5; P = 0.0009). In addition, fellowship attainment did not correlate with the size of the employing academic program, population of the city of practice, or being a residency director or chair.

CONCLUSION

The majority of APSs have undergone fellowship training, and there is very strong evidence supporting its impact in current entry and advancement in academic plastic surgery.

Independent or Integrated Plastic Surgery Residency Pathways: Trends in Representation in Academic Plastic Surgery in the United States

INTRODUCTION

The training pathway for plastic surgery has evolved in recent years with the adoption and rise in popularity of the integrated model. Studies have demonstrated that there may be differences between integrated graduates and independent graduates, specifically in career choices and type of practice. This study seeks to understand if there are differences in representation at academic and leadership positions between graduates of the 2 pathways.

METHODS

A cross-sectional study was conducted in June of 2018 to assess integrated and independent pathway graduate's representation in academic plastic surgery in the United States. Factors examined were career qualifications, academic productivity, faculty positions, and influence of pathway on career advancement.

RESULTS

A total of 924 academic plastic surgeons were analyzed, 203 (22.0%) of whom were integrated graduates and 721 (78.0%) of whom were independent graduates. Independent graduates had greater National Institutes of Health funding (integrated, $40,802; independent, $257,428; P = 0.0043), higher h-index (integrated, 7.0; independent, 10.0; P < 0.001), and higher publication number (integrated, 17; independent, 25; P = 0.0011). Integrated graduates were more likely to be assistant professors (integrated, 70%; independent, 40.7%; P < 0.001) and required a shorter postresidency time to reach all positions examined compared with independent graduates.

CONCLUSIONS

Residency training pathway influences academic plastic surgeons in research output, qualifications, and academic positions. This is likely due to the relatively new nature of the integrated program compared with the independent, as well as the shorter length of training for integrated graduates. However, trends are moving toward integrated graduates showing increased interest and productivity in academic medicine.

Photocatalytic decarboxylative amidosulfonation enables direct transformation of carboxylic acids to sulfonamides

Sulfonamides feature prominently in organic synthesis, materials science and medicinal chemistry, where they play important roles as bioisosteric replacements of carboxylic acids and other carbonyls. Yet, a general synthetic platform for the direct conversion of carboxylic acids to a range of functionalized sulfonamides has remained elusive. Herein, we present a visible light-induced, dual catalytic platform that for the first time allows for a one-step access to sulfonamides and sulfonyl azides directly from carboxylic acids. The broad scope of the direct decarboxylative amidosulfonation (DDAS) platform is enabled by the efficient direct conversion of carboxylic acids to sulfinic acids that is catalyzed by acridine photocatalysts and interfaced with copper-catalyzed sulfur-nitrogen bond-forming cross-couplings with both electrophilic and nucleophilic reagents.

Characteristics and Academic Productivity Among Pediatric Plastic Surgeons in the United States

BACKGROUND

The characteristics that predispose plastic surgeons to a career in pediatric plastic surgery remain unclear. Therefore, the aim of this study is to analyze the characteristics of current pediatric plastic surgeons and to determine their academic productivity.

METHODS

Pediatric plastic surgeons were identified through an internet search of all academic children's hospitals affiliated with an Accreditation Council for Graduate Medical Education-accredited integrated or independent plastic surgery program. Demographics, training background, institutional and leadership positions, and academic productivity were determined.

RESULTS

A total of 304 pediatric plastic surgeons were identified. The majority of pediatric plastic surgeons were white (n = 217, 71.8%) males (n = 235, 77.6%). Clinical fellowships were completed by 86.8% (n = 263) of the cohort, with craniofacial (n = 181, 59.7%) being the most common followed by hand (n = 54, 17.8%); 41.1% had clinical fellowship training at 10 institutions, with the top 3 most represented programs being University of Pennsylvania (n = 19, 6.2%), University of California-Los Angeles (n = 16, 5.3%), and Harvard University (n = 15, 4.9%); 25.7% (n = 78) held leadership positions within their institutions. A significant higher academic productivity was found among research fellowship-trained surgeons, chiefs of pediatric plastic surgery, fellowship directors, and members of departments of plastic surgery. Those who completed an independent residency had a significant higher H-index and number of citations.

CONCLUSION

Pediatric plastic surgery is represented by surgeons of diverse training background. An elite cohort of programs has trained the most pediatric plastic surgeons. Lastly, high academic productivity was found to be correlated with certain demographic and leadership variables highlighting its impact on career advancement.

Association Between Epidural Analgesia During Labor and Risk of Autism Spectrum Disorders in Offspring

IMPORTANCE

Although the safety of labor epidural analgesia (LEA) for neonates has been well documented, the long-term health effects of LEA on offspring remain to be investigated.

OBJECTIVE

To assess the association between maternal LEA exposure and risk of autism spectrum disorders (ASDs) in offspring.

DESIGN, SETTING, AND PARTICIPANTS

Data for this retrospective longitudinal birth cohort study were derived from electronic medical records from a population-based clinical birth cohort. A total of 147 895 singleton children delivered vaginally between January 1, 2008, and December 31, 2015, in a single integrated health care system were included. Children were followed up from the age of 1 year until the first date of the following occurrences: clinical diagnosis of ASD, last date of health plan enrollment, death, or the study end date of December 31, 2018.

EXPOSURES

Use and duration of LEA.

MAIN OUTCOMES AND MEASURES

The main outcome was clinical diagnosis of ASD. Cox proportional hazards regression analysis was used to estimate the hazard ratio (HR) of ASD associated with LEA exposure.

RESULTS

Among the cohort of 147 895 singleton children (74 425 boys [50.3%]; mean [SD] gestational age at delivery, 38.9 [1.5] weeks), 109 719 (74.2%) were exposed to maternal LEA. Fever during labor was observed in 13 055 mothers (11.9%) in the LEA group and 510 of 38 176 mothers (1.3%) in the non-LEA group. Autism spectrum disorders were diagnosed in 2039 children (1.9%) in the LEA group and 485 children (1.3%) in the non-LEA group. After adjusting for potential confounders, including birth year, medical center, maternal age at delivery, parity, race/ethnicity, educational level, household income, history of comorbidity, diabetes during pregnancy, smoking during pregnancy, preeclampsia or eclampsia, prepregnancy body mass index, gestational weight gain, gestational age at delivery, and birth weight, the HR associated with LEA vs non-LEA exposure was 1.37 (95% CI, 1.23-1.53). Relative to the unexposed group, the adjusted HR associated with LEA exposure of less than 4 hours was 1.33 (95% CI, 1.17-1.53), with LEA exposure of 4 to 8 hours was 1.35 (95% CI, 1.20-1.53), and with LEA exposure of more than 8 hours was 1.46 (95% CI, 1.27-1.69). Within the LEA group, there was a significant trend of ASD risk associated with increasing duration of LEA exposure after adjusting for covariates (HR for linear trend, 1.05 [95% CI, 1.01-1.09] per 4 hours). Adding fever to the model did not change the HR estimate associated with LEA exposure (adjusted HR for LEA vs non-LEA, 1.37 [95% CI, 1.22-1.53]).

CONCLUSIONS AND RELEVANCE

This study suggests that maternal LEA may be associated with increased ASD risk in children. The risk appears to not be directly associated with epidural-related maternal fever.

Acridine Photocatalysis: Insights into the Mechanism and Development of a Dual-Catalytic Direct Decarboxylative Conjugate Addition

Conjugate addition is one of the most synthetically useful carbon‒carbon bond-forming reactions, however, reactive carbon nucleophiles are typically required to effect the addition. Radical conjugate addition provides an avenue for replacing reactive nucleophiles with convenient radical precursors. Carboxylic acids can serve as simple and stable radical precursors by way of decarboxylation, but activation to reactive esters is typically necessary to facilitate the challenging decarboxylation. Here, we report a direct, dual-catalytic decarboxylative radical conjugate addition of a wide range of carboxylic acids that does not require acid preactivation and is enabled by the visible light-driven acridine photocatalysis interfaced with an efficient copper catalytic cycle. Mechanistic and computational studies provide insights into the roles of the ligands and metal species in the dual catalytic process and the photocatalytic activity of substituted acridines.

Visible-Light-Enabled Direct Decarboxylative N-Alkylation

The development of efficient and selective C-N bond-forming reactions from abundant feedstock chemicals remains a central theme in organic chemistry owing to the key roles of amines in synthesis, drug discovery, and materials science. Herein, we present a dual catalytic system for the N-alkylation of diverse aromatic carbocyclic and heterocyclic amines directly with carboxylic acids, by-passing their preactivation as redox-active esters. The reaction, which is enabled by visible-light-driven, acridine-catalyzed decarboxylation, provides access to N-alkylated secondary and tertiary anilines and N-heterocycles. Additional examples, including double alkylation, the installation of metabolically robust deuterated methyl groups, and tandem ring formation, further demonstrate the potential of the direct decarboxylative alkylation (DDA) reaction.

Respiratory Volume Monitoring in the Perioperative Setting Across Multiple Centers

BACKGROUND

The prevalence of nuisance (technical) alarms is the leading cause of alarm fatigue resulting in decreased awareness and a reduction in effective care. The Joint Commission identified in their National Patient Safety goals alarm fatigue as a major safety issue. The introduction of noninvasive respiratory volume monitoring (RVM) has implications for effective perioperative respiratory status management. We evaluated this within the Kaiser Permanente health system.

METHODS

This observational study was conducted at 4 hospitals in the Kaiser Permanente system. Standard data from RVM, pulse oximetry, and capnography were collected postoperatively in the post-anesthesia care unit (PACU) and/or on the general hospital floor. Device-specific alarm types, rates, and respective actions were recorded and analyzed by non-study staff.

RESULTS

RVM was applied to 247 subjects (143 females, body mass index 32.3 ± 8.7 kg/m², age 60.9 ± 13.9 y) providing 2,321 h. RVM alarms occurred 605 times (0.25 alarms/h); 64% were actionable and addressed, 17% were not addressed, 13% were self-resolved, and only 6% were nuisance. In a subgroup, RVM completed all 127 h of monitoring, whereas oximetry with capnography only completed 51 h with 12.9 alarms/h (73% nuisance). The overall RVM alarm rate was significantly lower than with either pulse oximeters or capnography monitors. We saw a nearly 1,000-fold reduction in nuisance alarms compared to capnography and a 20-50-fold reduction in nuisance alarms compared to pulse oximetry.

CONCLUSIONS

Our study indicates that alarm fatigue due to nuisance alarms continues to be a clinical challenge in perioperative settings. Among the 3 common technologies for respiratory function monitoring, RVM had the lowest rate of overall technical alarms and the highest rate of compliance. Furthermore, with early interventions, none of the subjects monitored with RVM suffered any negative outcomes.

Feasibility of Aerosol Bronchodilators Delivery Through High-Flow Nasal Cannula in Pediatric Subjects With Respiratory Distress

BACKGROUND

High-flow nasal cannula (HFNC) is commonly used to provide respiratory support to pediatric patients with respiratory failure. Although the use of bronchodilators via HFNC has been described, the feasibility and safety of aerosolized bronchodilator delivery via HFNC are controversial. In this study, we sought to evaluate whether the HFNC system can be used to deliver nebulized bronchodilators at lower gas flow of 2-4 L/min, increase patient comfort, and minimize respiratory therapist (RT) bedside time when compared to traditional interfaces.

METHODS

A retrospective chart review of all pediatric subjects who were admitted to the pediatric ICU in a tertiary care children's hospital and required nebulized bronchodilators between December 2017 and June 2018.

RESULTS

A total of 205 nebulizations were administered to 28 children; 31% of nebulized bronchodilators were given using a nebulization system integrated into the HFNC. Nebulized treatments resulted in an average increase in heart rate of 9.98 (95% CI 3.72-16.2) beats/min when HFNC was used and 0.64 (95% CI -1.65 to 2.93) beats/min when traditional interfaces were used, a difference of 9.34 (95% CI 2.30-16.4) beats/min (P < .001). RT bedside time was significantly longer for HFNC nebulized treatments (P = .031). Subjective level of comfort was not statically different when nebulized bronchodilators were delivered via HFNC or via traditional interfaces. Length of pediatric ICU stay was not statistically different between subjects who received some aerosol nebulized bronchodilators via HFNC versus those who received all bronchodilators through traditional interfaces (P = .11).

CONCLUSIONS

Aerosol bronchodilator delivery using HFNC is feasible at low gas flow (ie, 2-4 L/min). However, the use of HFNC did not improve subjects' comfort, and it increased RT bedside time. Further prospective randomized studies are needed to determine the efficacy and efficiency of aerosol therapy delivered through HFNC and potential patient-oriented outcomes.

Visible Light-Induced Borylation of C-O, C-N, and C-X Bonds

Boronic acids are centrally important functional motifs and synthetic precursors. Visible light-induced borylation may provide access to structurally diverse boronates, but a broadly efficient photocatalytic borylation method that can effect borylation of a wide range of substrates, including strong C-O bonds, remains elusive. Herein, we report a general, metal-free visible light-induced photocatalytic borylation platform that enables borylation of electron-rich derivatives of phenols and anilines, chloroarenes, as well as other haloarenes. The reaction exhibits excellent functional group tolerance, as demonstrated by the borylation of a range of structurally complex substrates. Remarkably, the reaction is catalyzed by phenothiazine, a simple organic photocatalyst with MW < 200 that mediates the previously unachievable visible light-induced single electron reduction of phenol derivatives with reduction potentials as negative as approximately - 3 V versus SCE by a proton-coupled electron transfer mechanism. Mechanistic studies point to the crucial role of the photocatalyst-base interaction.

Bond Memory in Dynamically Determined Stereoselectivity

The carboborative ring contraction of cyclohexenes exhibits an abnormal selectivity pattern in which a formally concerted double migration gives rise to predominant but not exclusive inversion products. In dynamic trajectories, the inversion and retention products are formed from the same transition state, and the trajectories accurately account for the experimental product ratios. The unusual origin of the selectivity is the dynamically retained non-equivalence of newly formed versus pre-existing bonds after the first bond migration.

New species and new genus of Pseudohaploporinae (Digenea): Pseudohaploporus pusitestis sp. n. and Parahaploporus elegantus n. g., sp. n. (Digenea: Pseudohaploporinae) from Vietnamese mullet fish

Two new species of Pseudohaploporinae, Pseudohaploporus pusitestis sp. n. and Parahaploporus elegantus n. g., sp. n., are described from intestines of the Vietnamese mullet fish Moolgarda seheli and Osteomugil cunnesius, respectively. Pseudohaploporus pusitestis sp. n. differs from two known Pseudohaploporus species, P. vietnamensis and P. planiliza, by the absence of a diverticulate hermaphroditic duct and muscular sphincters at the proximal end of the hermaphroditic sac. Metrically, P. pusitestis sp. n. is close to P. vietnamensis and differs from this species and from P. planilizum by lower maximum sizes of most parameters. Parahaploporus elegantus n. g., sp. differs from representatives of Pseudohaploporus by the presence of a single testis and the armament of hermaphroditic duct and is morphologically close to trematodes of the genus Haploporus. However, P. elegantus n. g differs from all known Haploporus species from mugilids of the Indo-West Pacific by the structure of the armament of the hermaphroditic duct and also by size of body, organs and eggs. The validity of designating two new species and a new genus of trematodes is supported by ITS and 28S rDNA sequence data. Phylogenetic reconstructions showed that the new trematodes belong to the Pseudohaploporinae, which formed a well-supported cluster within the monophyletic Haploporidae.

Paediatric use of antibiotics in children with community acquired pneumonia: A survey from Da Nang, Vietnam

AIM

To characterise paediatricians' antibiotic-prescribing behaviour when managing community acquired pneumonia.

METHODS

We conducted a knowledge and attitudes survey of paediatric doctors practicing at a regional provincial hospital in central Vietnam over a 2-week period (from 12 December 2017 to 29 December 2017).

RESULTS

Of 79 eligible paediatric doctors, 69 (87.3%) completed the questionnaire, of whom 65 (94.2%) thought that antibiotics were overused in Vietnam. Thirty-eight doctors (55.1%) indicated that they routinely hospitalised children with pneumonia to provide intravenous antibiotics. Most doctors reported discharging children with non-severe pneumonia after 5 days (76.9%) and those with severe pneumonia after 7-10 days (88.4%); older doctors generally continued intravenous antibiotics for longer. The two most important factors driving discharge decisions were clinical assessment (95.6%) and completion of the full course of intravenous antibiotics (80.0%). Antibiotic prescription was influenced by local guidelines (62.3%), drugs used before admission (50.0%) and the opinion of senior clinicians (37.7%). Most doctors believed antibiotic stewardship was necessary (98.6%) and that over-the-counter use of antibiotics should be restricted (97.1%).

CONCLUSIONS

Paediatricians recognised an urgent need for more effective regulation and antibiotic stewardship in Vietnam. Routinely completing a full course of intravenous antibiotics leads to unnecessary and prolonged hospitalisation.

Hexahydropyrrolo[2,3-b]indole Compounds as Potential Therapeutics for Alzheimer's Disease

Alzheimer's disease (AD) is the most common form of dementia among the elderly and has become a leading public health concern worldwide. It represents a huge economic and psychological burden to caregivers and families. The presence of extracellular amyloid beta (Aβ) plaques is one of the hallmarks of this neurodegenerative disorder. Amyloid plaques are comprised of aggregates of Aβ peptides, mainly Aβ₄₂, originated by the cleavage of the amyloid precursor protein (APP). Aβ is a crucial target for the treatment of AD, but to date, no effective treatment for the clearance of Aβ has been found. We have identified four new hexahydropyrroloindoles (HPI) synthetic compounds that are able to inhibit the aggregation of Aβ₄₂ and/or disaggregate the fibril. Docking experiments suggest that the nonpolar component of the interaction of compounds with Aβ₄₂ contributes favorably to the binding free energy of each complex. Molecular dynamics simulations suggested fibril disaggregating activity of compounds 1 via interaction with hydrophobic moieties of the fibril. Consistently, compounds 1 and 2 were able to mitigate Aβ₄₂ fibrils induced death in rat pheochromocytoma cells (PC 12). One of the compounds reduces the formation of Aβ aggregates in vivo and the paralysis associated with Aβ toxicity in Caenorhabditis elegans. Our study thus augments efforts for the identification and characterization of new agents that may help stop or delay the progression of AD.

Alkene Synthesis by Photocatalytic Chemoenzymatically Compatible Dehydrodecarboxylation of Carboxylic Acids and Biomass

Direct conversion of renewable biomass and bioderived chemicals to valuable synthetic intermediates for organic synthesis and materials science applications by means of mild and chemoselective catalytic methods has largely remained elusive. Development of artificial catalytic systems that are compatible with enzymatic reactions provides a synergistic solution to this enduring challenge by leveraging previously unachievable reactivity and selectivity modes. We report herein a dual catalytic dehydrodecarboxylation reaction that is enabled by a crossover of the photoinduced acridine-catalyzed O-H hydrogen atom transfer (HAT) and cobaloxime-catalyzed C-H-HAT processes. The reaction produces a variety of alkenes from readily available carboxylic acids. The reaction can be embedded in a scalable triple-catalytic cooperative chemoenzymatic lipase-acridine-cobaloxime process that allows for direct conversion of plant oils and biomass to long-chain terminal alkenes, precursors to bioderived polymers.

Decorin age-related variations in the distribution of pig extracellular matrix meniscus

Menisci act like shock absorbers and transmit load across the tibiofemoral joint by increasing congruency during movements or body weight load. This leads to decreasing the resultant stress on the articular cartilages. The meniscus has a dense extracellular matrix (ECM) composed of water, different types of collagens, and proteoglycans, such as decorin, aggrecan and biglycan. Decorin (DCN) regulates collagen fibrillogenesis acting on collagen fibrils diameter and fibrils orientation to achieve the proper assembly of its network. This work investigates the spatial disposition of this fundamental protein in pig meniscus' matrix by immunohistochemistry and western blot analysis. DCN shows an increasing trend, moving from neonatal to adult pig menisci. Adult meniscus, in porcine species, is the only one that could be considered fully mature and functional, and, even if an increasing trend is seen, no precise phenotypical switch points are seen in the age stages considered in this study.

Efficient synthesis of 3-sulfolenes from allylic alcohols and 1,3-dienes enabled by sodium metabisulfite as a sulfur dioxide equivalent

We present herein an efficient and practical method for a gram scale synthesis of 3-sulfolenes using sodium metabisulfite as a safe, inexpensive, and easy to handle sulfur dioxide equivalent. Diversely-substituted 3-sulfolenes can be prepared by reacting a variety of 1,3-dienes or allylic alcohols with sodium metabisulfite in aqueous hexafluoroisopropanol (HFIP) or in aqueous methanol in the presence of potassium hydrogen sulfate. Advantageously, the method enables conversion of allylic alcohols directly to 3-sulfolenes, bypassing intermediate 1,3-dienes.

Organoboron chemistry comes to light: recent advances in photoinduced synthetic approaches to organoboron compounds

Photoinduced synthetic approaches to organoboron compounds have attracted significant attention in the recent years. Photochemical activation of organic molecules enables generation of reactive intermediates from a variety of precursors, resulting in borylation methods with improved and broader substrate scopes. The review summarizes recent developments in the area of photoinduced reactions of organoboron compounds with an emphasis on borylation of haloarenes, amine derivatives, and redox-active esters of carboxylic acids, as well as photoinduced rearrangements of organoboron compounds and photoinduced synthesis of organoboron compounds from alkenes and alkynes.

Characterization of different in vitro culture conditions to induce a fibro-chondrogenic differentiation of swine adipose-derived stem cells

Meniscus repair is still a challenge for orthopaedic surgeons as this tissue has a scarce healing potential due to the limited vascularization and to the lack of progenitor cells. Lately, several tissue engineering strategies combining cells and scaffolds have been developed. Adipose-derived stem cells (ASCs) represent a novel cell source for meniscus repair as they are easy to harvest, and they possess an intrinsic chondrogenic potential. The aim of our study was to analyze and compare the chondrogenic differentiation of swine ASCs cultured in vitro with different supplemented media. We isolated ASCs from swine adipose tissue and we placed in pellet cultures supplemented with either Bone Morphogenetic Protein (BMP)-2 and Transforming Growth Factor (TGF)-β3 or with Bone Morphogenetic Protein (BMP)-7 and Transforming Growth Factor (TGF)-β1. Samples were analyzed after 7, 14 or 21 days of culture by biochemical, histological and gene expression analysis. Our preliminary results show that BMP-2 and TGF-β3 are stronger inducers of chondrogenesis.

Animal models for cartilage repair

Cartilage lesions still represent an unsolved problem: despite the efforts of the basic and translational research, the regeneration of this tissue is far from being reached (1-3). Articular cartilage lesions can be divided in two main groups: superficial or partial defects and full-thickness defects (4, 5). Partial lesions are not able to self-heal because multipotent cells from the bone marrow cannot reach the area leading to a progressive degeneration of the tissue (6). Conversely, full-thickness injuries possess greater chances to heal because subchondral bone involvement allows for the migration of mesenchymal cells, which fill the damaged area (7, 8). However, healing occurs through the formation of a fibrocartilaginous tissue, which has different biomechanical and biological properties (9). Native hyaline cartilage has indeed specific biomechanical properties, which confer resistance to compressive and shear stresses; the reparative fibrocartilaginous tissue lacks these abilities, therefore, the surrounding healthy cartilage progressively degenerates. In the past years, several therapeutic strategies have been developed to restore the damaged cartilage, bone marrow stimulation (chondroabrasion, drilling, micro- or nano-fractures) and more recently, tissue engineering approaches (10-14). Some of these latter procedures have already been applied in clinical practice such as matrix-induced autologous chondrocyte implantation (MACI) (15) or osteochondral scaffold implantation (16). Generally, tissue engineering approaches are based on the combination of three main elements: cells (i.e. primary chondrocytes or multipotent mesenchymal cells), biocompatible scaffolds (i.e. polymers, composites, ceramics) and signaling molecules (i.e. growth factors). Moreover, several culture conditions (i.e. static or dynamic cultures) and biomechanical stimuli can be applied during the in vitro culture to promote tissue maturation (17-19). However, an in vivo culture is mandatory to validate a new engineered construct as the in vitro phase lacks the essential in vivo environmental stimuli and because the in vivo culture allows for the testing of the biocompatibility and safety of a new material (18, 19). Moreover, preclinical animal models are crucial to understand the molecular mechanisms of cartilage lesions favoring the development of new regenerative strategies (20, 21). in vivo studies on animal models should focus on the analysis of the cellular component, analyzing the maintenance of the cellular phenotype and the tumorigenicity; on the evaluation of the biocompatibility, toxicity and degradation of the biomaterial and on the assessment of the engineered construct. In this manuscript, we will review the most common preclinical animal models, which are used to understand cartilage biology and therefore to develop new tissue engineering strategies. We will focus on both small and large animal models highlighting their peculiarities, advantages and drawbacks.