Risk factors for adverse outcomes following paraesophageal hernia repair among obese patients.

BACKGROUND: Although obesity is an established risk factor for adverse outcomes after paraesophageal hernia repair (PEHR), many obese patients nonetheless receive PEHR. The purpose of this study was to explore risk factors for adverse outcomes of PEHR among this high-risk cohort. We hypothesized that obese patients may have other risk factors for adverse outcomes following PEHR. METHODS: A retrospective study of adult obese patients who underwent minimally invasive PEHR from 2017 to 2019 was performed. Patients were excluded for BMI < 30 or if they had concomitant bariatric surgery at time of PEHR. The primary outcome of interest was a composite adverse outcome (CAO) defined as having any of the four following outcomes after PEHR: persistent GERD > 30 d, persistent dysphagia > 30 d, recurrence, or reoperation. Chi-square and t-test analysis was used to compare demographic and clinical characteristics. Multivariable logistic regression analysis was used to evaluate independent predictors of CAO. RESULTS: In total, 139 patients met inclusion criteria with a median follow-up of 19.7 months (IQR 8.8-81). Among them, 51/139 (36.7%) patients had a CAO: 31/139 (22.4%) had persistent GERD, 20/139 (14.4%) had persistent dysphagia, 24/139 (17.3%) had recurrence, and 6/139 (4.3%) required reoperation. On unadjusted analysis, patients with a CAO were more likely to have a history of prior abdominal surgery (86.3% vs 70.5%, p = 0.04) and were less likely to have undergone a preoperative CT scan (27.5% vs 45.5%, p = 0.04). On multivariable analysis, previous abdominal surgery was independently associated with an increased likelihood of CAO whereas age and preoperative CT scan had a decreased likelihood of CAO. CONCLUSIONS: Although there were adverse outcomes among obese patients, minimally invasive PEHR may be feasible in a subset of patients at specialized centers. These findings may help guide the appropriate selection of obese patients for PEHR.

An Analysis of Medical Student PubMed-Indexed Research Productivity and Factors Associated With Matching at Top-Ranked Ophthalmology Residency Programs.

Background Limited information exists regarding the research productivity of matched ophthalmology applicants given that ophthalmology residencies do not participate in the National Residency Match Program. Objectives This study determines the research productivity characteristics of matched ophthalmology applicants and variables associated with matching to higher-tier ophthalmology residency programs. Methods Medical school, matched residency program, and applicant-specific PubMed-indexed research productivity (including consideration for first-author publications, relevance to ophthalmology, and acceptance before application submission date) for 2020-2021 matched ophthalmology applicants were collected from publicly available websites. Statistical analysis was conducted using chi-squared tests and t-tests to compare research productivity between groups (gender, medical school tier, and ophthalmology residency program Doximity rank). Multivariate regression was used to analyze research factors associated with matching at the top 20 Doximity-ranked ophthalmology residency programs. Results Three hundred ninety-three matched ophthalmology applicants for the 2020-2021 academic year were analyzed with an average of 2.4 ± 3.1 (median: 1 {0-3}) publications, 1.0 ± 2.1 (median: 0 {0-1}) ophthalmic publications, 0.8 ± 1.4 (median: 0 {0-1}) first-author publications, and 0.5 ± 1.1 (median: 0 {0-1}) ophthalmic first-author publications. The applicants who matched at the top 20 Doximity-ranked ophthalmology residency programs were more likely to matriculate from the top 40 medical schools (63% versus 22%, p < 0.001), have more first-author publications at the time of application submission (1.1 ± 1.6 versus 0.7 ± 1.3, p = 0.044), and have more projects resulting in publications after submission (2.0 ± 2.5 versus 1.4 ± 2.3, p = 0.048). In multivariate regression, attendance at a top 40 medical school (adjusted odds ratio {aOR} = 6.07, 95% confidence interval {CI}: 3.56-10.5, p < 0.001) was a significant predictor of matching at a top 20 Doximity ophthalmology residency program, and no variables associated with research productivity were significant predictors. Conclusions There has been a consistent increase in research productivity among matched ophthalmology applicants. However, in multivariate analysis, the medical school tier was the only significant variable for matching at top-tier programs. More nuanced studies regarding the effect of research productivity on ophthalmology applicants are needed.

PMMA Bone Cement Composite Functions as an Adjuvant Chemotherapeutic Platform for Localized and Multi-Window Release during Bone Reconstruction.

Primary bone tumor resections often result in critical size defects, which then necessitate challenging clinical management approaches to reconstruct. One such intervention is the Masquelet technique, in which poly(methyl methacrylate) (PMMA) bone cement is placed as a spacer temporarily while adjuvant chemotherapeutics are administered systemically. The spacer is later removed and replaced with bone autograft. Local recurrence remains an important and devastating problem, therefore, a system capable of locally delivering chemotherapeutics will present unique advantages. In this work, a refillable chemotherapeutic (doxorubicin, DOX) delivery platform comprised of PMMA bone cement and insoluble γ-cyclodextrin (γ-CD) polymeric microparticles is developed and explored towards application as a temporary adjuvant chemotherapeutic spacer. The system is characterized for porosity, mechanical strength, DOX filling and refilling capacity, elution kinetics, and cytotoxicity. Since residual chemotherapeutics can adversely impact bone healing, it is important that virtually all DOX be released from material. Composites containing 15 wt% γ-CD microparticles demonstrate 100% DOX release within 100 days, whereas only 6% DOX is liberated from PMMA with free DOX over same period. Refillable properties of PMMA composite system may find utility for customizing dosing regimens. Findings suggest that PMMA composites can have potential as chemotherapeutic delivery platforms to assist in bone reconstruction.

Development of Hydrogen-Rich Benzoxazine Resins with Low Polymerization Temperature for Space Radiation Shielding.

A systematic study has been carried out to develop a material with significant protection properties from galactic cosmic radiation and solar energetic particles. The research focused on the development of hydrogen-rich benzoxazines, which are particularly effective for shielding against such radiation. Newly developed benzoxazine resin can be polymerized at 120 °C, which meets the low-temperature processing requirements for use with ultrahigh molecular weight polyethylene (UHMWPE) fiber, a hydrogen-rich composite reinforcement. This highly reactive benzoxazine resin also exhibits low viscosity and good shelf-life. The structure of the benzoxazine monomer is confirmed by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. Polymerization behavior and thermal properties are evaluated by differential scanning calorimetry and thermogravimetric analysis. Dynamic mechanical analysis is used to study chemorheological properties of the benzoxazine monomer, rheological properties of the cross-linked polybenzoxazine, and rheological properties of UHMWPE-reinforced polybenzoxazine composites. The theoretical radiation shielding capability of the composite is also evaluated using computer-based simulations.