Developing a Dedicated Leadership Curriculum for Radiation Oncology Residents.

The increasing complexity of healthcare emphasizes the need for continued physician leadership and leadership training. This study aims to determine baseline attitudes toward the perceptions and utility of a leadership development curriculum (LDC) for radiation oncology (RO) residents. A novel longitudinal LDC was implemented for RO residents at our institution from 2018 to 2019. Prior to the curriculum, current and past residents in our institution's RO residency program were surveyed on their attitudes towards leadership in healthcare, emotional intelligence competencies, and leadership training interests. After the completion of the LDC, a post-curriculum survey was forwarded to current residents. The response rate was 84% (21 of 24) for the baseline survey and 90% (9 of 10) for the post-curriculum survey. Having a leadership training curriculum during residency was rated as extremely useful, with top training interests involving leading clinical teams, effective communication strategies, and conflict management. After the LDC, the residents reported high satisfaction with the curriculum and utilization of leadership training into their daily work. Our LDC demonstrates significant potential to engage trainees and improve their leadership skills at the graduate medical education level.

Depression, anxiety, and burnout among hospital workers during the COVID-19 pandemic: A cross-sectional study.

OBJECTIVES: Healthcare personnel have faced unprecedented mental health challenges during the COVID-19 pandemic. The study objective is to assess differences in depression, anxiety, and burnout among healthcare personnel with various occupational roles and whether financial and job strain were associated with these mental health outcomes. METHODS: We employed an anonymous survey between July and August 2020 at an urban county hospital in California, USA. We assessed depression, anxiety, and burnout using validated scales, and asked questions on financial strain and job strain. We performed logistic and linear regression analyses. RESULTS: Nurses (aOR 1.93, 95% CIs 1.12, 3.46), social workers (aOR 2.61, 95% CIs 1.35, 5.17), service workers (aOR 2.55, 95% CIs 1.20, 5.48), and administrative workers (aOR 2.93, 95% CIs 1.57, 5.61) were more likely than physicians to screen positive for depression. The odds of screening positive for anxiety were significantly lower for ancillary workers (aOR 0.32, 95% CIs 0.13-0.72) compared with physicians. Ancillary (aB = -1.77, 95% CIs -1.88, -0.47) and laboratory and pharmacy workers (aB -0.70, 95% CI -1.34, -0.06) reported lower levels of burnout compared with physicians. Financial strain partially accounted for differences in mental health outcomes across job categories. Lack of time to complete tasks and lack of supervisory support were associated with higher odds of screening positive for depression. Less job autonomy was associated with higher odds of screening positive for anxiety and higher burnout levels. CONCLUSIONS: We found significant disparities in mental health outcomes across occupational roles. Policies to mitigate the adverse impact of COVID-19 on health workers' mental health should include non-clinical staff and address financial support and job characteristics for all occupational roles.

Dynamic Electromechanical Hydrogel Matrices for Stem Cell Culture.

Hydrogels have numerous biomedical applications including synthetic matrices for cell culture and tissue engineering. Here we report the development of hydrogel based multifunctional matrices that not only provide three-dimensional structural support to the embedded cells but also can simultaneously provide potentially beneficial dynamic mechanical and electrical cues to the cells. A unique aspect of these matrices is that they undergo reversible, anisotropic bending dynamics in an electric field. The direction and magnitude of this bending can be tuned through the hydrogel crosslink density while maintaining the same electric potential gradient, allowing control over the mechanical strain imparted to the cells in a three-dimensional environment. The conceptual design of these hydrogels was motivated through theoretical modeling of the osmotic pressure changes occurring at the gel-solution interfaces in an electric field. These electro-mechanical matrices support survival, proliferation, and differentiation of stem cells. Thus, these new three-dimensional in vitro synthetic matrices, which mimic multiple aspects of the native cellular environment, take us one step closer to in vivo systems.

Temperature dependence of electron transfer to the M-side bacteriopheophytin in rhodobacter capsulatus reaction centers.

Subpicosecond time-resolved absorption measurements at 77 K on two reaction center (RC) mutants of Rhodobacter capsulatus are reported. In the D(LL) mutant the D helix of the M subunit has been substituted with the D helix from the L subunit, and in the D(LL)-FY(L)F(M) mutant, three additional mutations are incorporated that facilitate electron transfer to the M side of the RC. In both cases the helix swap has been shown to yield isolated RCs that are devoid of the native bacteriopheophytin electron carrier HL (Chuang, J. I.; Boxer, S. G.; Holten, D.; Kirmaier, C. Biochemistry 2006, 45, 3845-3851). For D(LL), depending whether the detergent Deriphat 160-C or N-lauryl-N,N-dimethylamine-N-oxide (LDAO) is used to suspend the RCs, the excited state of the primary electron donor (P*) decays to the ground state with an average lifetime at 77 K of 330 or 170 ps, respectively; however, in both cases the time constant obtained from single-exponential fits varies markedly as a function of the probe wavelength. These findings on the D(LL) RC are most easily explained in terms of a heterogeneous population of RCs. Similarly, the complex results for D(LL)-FY(L)F(M) in Deriphat-glycerol glass at 77 K are most simply explained using a model that involves (minimally) two distinct populations of RCs with very different photochemistry. Within this framework, in 50% of the D(LL)-FY(L)F(M) RCs in Deriphat-glycerol glass at 77 K, P* deactivates to the ground state with a time constant of approximately 400 ps, similar to the deactivation of P* in the D(LL) mutant at 77 K. In the other 50% of D(LL)-FY(L)F(M) RCs, P* has a 35 ps lifetime and decays via electron transfer to the M branch, giving P+HM- in high yield (> or =80%). This result indicates that P* --> P(+)H(M)(-) is roughly a factor of 2 faster at 77 K than at 295 K. In alternative homogeneous models the rate of this M-side electron-transfer process is the same or up to 2-fold slower at low temperature. A 2-fold increase in rate with a reduction in temperature is the same behavior found for the overall L-side process P* --> P(+)H(L)(-) in wild-type RCs. Our results suggest that, as for electron transfer on the L side, the M-side electron-transfer reaction P* --> P(+)H(M)(-) is an activationless process.

Overview of Facial Plastic Surgery and Current Developments.

Facial plastic surgery is a multidisciplinary specialty largely driven by otolaryngology but includes oral maxillary surgery, dermatology, ophthalmology, and plastic surgery. It encompasses both reconstructive and cosmetic components. The scope of practice for facial plastic surgeons in the United States may include rhinoplasty, browlifts, blepharoplasty, facelifts, microvascular reconstruction of the head and neck, craniomaxillofacial trauma reconstruction, and correction of defects in the face after skin cancer resection. Facial plastic surgery also encompasses the use of injectable fillers, neural modulators (e.g., BOTOX Cosmetic, Allergan Pharmaceuticals, Westport, Ireland), lasers, and other devices aimed at rejuvenating skin. Facial plastic surgery is a constantly evolving field with continuing innovative advances in surgical techniques and cosmetic adjunctive technologies. This article aims to give an overview of the various procedures that encompass the field of facial plastic surgery and to highlight the recent advances and trends in procedures and surgical techniques.

The kinetic pathway of folding of barnase.

To search for folding intermediates, we have examined the folding and unfolding kinetics of wild-type barnase and four representative mutants under a wide range of conditions that span two-state and multi-state kinetics. The choice of mutants and conditions provided in-built controls for artifacts that might distort the interpretation of kinetics, such as the non-linearity of kinetic and equilibrium data with concentration of denaturant. We measured unfolding rate constants over a complete range of denaturant concentration by using by 1H/2H-exchange kinetics under conditions that favour folding, conventional stopped-flow methods at higher denaturant concentrations and continuous flow. Under conditions that favour multi-state kinetics, plots of the rate constants for unfolding against denaturant concentration fitted quantitatively to the equation for three-state kinetics, with a sigmoid component for a change of rate determining step, as did the refolding kinetics. The position of the transition state on the reaction pathway, as measured by solvent exposure (the Tanford beta value) also moved with denaturant concentration, fitting quantitatively to the same equations with a change of rate determining step. The sigmoid behaviour disappeared under conditions that favoured two-state kinetics. Those data combined with direct structural observations and simulation support a minimal reaction pathway for the folding of barnase that involves two detectable folding intermediates. The first intermediate, I(1), is the denatured state under physiological conditions, D(Phys), which has native-like topology, is lower in energy than the random-flight denatured state U and is suggested by molecular dynamics simulation of unfolding to be on-pathway. The second intermediate, I(2), is high energy, and is proven by the change in rate determining step in the unfolding kinetics to be on-pathway. The change in rate determining step in unfolding with structure or environment reflects the change in partitioning of this intermediate to products or starting materials.

High yield of M-side electron transfer in mutants of Rhodobacter capsulatus reaction centers lacking the L-side bacteriopheophytin.

We present studies on a series of photosynthetic reaction center (RC) mutants created in the background of the Rhodobacter capsulatus D(LL) mutant, in which the D helix of the M subunit has been substituted with that from the L subunit. Previous work on the D(LL) mutant in chromatophore preparations showed that RCs assembled without the bacteriopheophytin H(L) electron acceptor and performed no charge separation following light absorption. We have successfully isolated poly-His-tagged D(LL) RCs by using the detergent Deriphat 160-C and shown that the RCs are devoid of H(L). The excited state of the primary electron donor, P*, is found to have a lifetime of 180 +/- 20 ps and to decay exclusively (>95%) via internal conversion to the ground state, with no evidence for formation of any charge-separated intermediates. By additional mutation in the D(LL) background of two residues that affect the P/P+ oxidation potential and one that facilitates M-side electron transfer, we achieve an unprecedented 70% yield of P+ H(M)-, more than doubling the highest yield of this state achieved previously. This result underscores the importance of the relative free energies of P* and the charge-separated states in governing the rates and yields of electron transfer in bacterial RCs and provides a basis for systematically investigating M-side electron transfer without any competition from the native L-side pathway.

Site-specific conversion of cysteine thiols into thiocyanate creates an IR probe for electric fields in proteins.

The nitrile stretching mode of the thiocyanate moiety is a nearly ideal probe for measuring the local electric field arising from the organized environment of the interior of a protein. Nitriles were introduced into three proteins: ribonuclease S (RNase S), human aldose reductase (hALR2), and the reaction center (RC) of Rhodobacter capsulatus, through a facile synthetic scheme for the transformation of cysteine residues into thiocyanatoalanine. Vibrational Stark effect spectroscopy and Fourier transform infrared spectroscopy on the modified proteins demonstrated that thiocyanate residues are a highly general tool for probing electrostatic fields in proteins.