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6062 Background: Induction chemotherapy (IC) is being studied as a chemoradiation (CRT) de-intensification strategy in HPV-related head and neck cancer (HNC), but using imaging response for eligibility selection is distinctly limited by delayed correlation with biological response and difficulty in distinguishing active tumor from treatment effect. We report serial cell free HPV DNA (cfHPV DNA) dynamics as a quantitative measure of early treatment responsiveness for HPV-related HNC patients receiving IC followed by CRT. Methods: Patients with high-risk HPV-positive (by in situ hybridization), locally advanced HNC who received IC followed by definitive CRT were enrolled starting on Sept 26, 2021. Patients received 1-2 cycles of platinum/taxane IC prior to initiating standard-dose CRT. Peripheral blood cfHPV DNA levels were measured biweekly during IC and weekly during CRT with the SafeSEQ HPV test from Sysmex Inostics, an NGS-based, CLIA-certified assay designed to sensitively detect and quantify HPV16 and HPV18 DNA in plasma. Tumor volumes were assessed on the pre- and post-IC planning CT scans by the treating radiation oncologist. Results: To date, 72 plasma samples have been processed across 11 enrolled patients with median age 66 years (range: 35-79). The primary disease sites included 7 oropharynx (OPX), 1 sinonasal, 2 nasopharyngeal, and 1 larynx. All patients had at least cT3 disease or cN3 disease (AJCC 8), with 6 patients having cT4 disease. Five (45.5%) have a smoking history, each > 10 pack-years. We report cfHPV DNA and tumor volume measurements at key timepoints for the 8 patients who have completed IC below. Conclusions: Serial cfHPV DNA identifies a group of locally advanced HPV-related HNC patients who have complete/near-complete cfDNA clearance during IC. This may provide an earlier readout of individualized treatment responsiveness compared to radiologic assessment, and may therefore be a preferred metric for CRT de-intensification eligibility. Clearance velocity will be evaluated with our granular biweekly IC and weekly CRT cfHPV DNA dataset to help further elucidate tumor response kinetics with this paradigm. [Table: see text]

Inhibitors of the bacterial enzyme dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE, EC 3.5.1.18) hold promise as antibiotics with a new mechanism of action. Herein we describe the discovery of a new series of indoline sulfonamide DapE inhibitors from a high-throughput screen and the synthesis of a series of analogs. Inhibitory potency was measured by a ninhydrin-based DapE assay recently developed by our group. Molecular docking experiments suggest active site binding with the sulfonamide acting as a zinc-binding group (ZBG).

The X-ray crystal structure of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase from Haemophilus influenzae (HiDapE) bound by the products of hydrolysis, succinic acid and l,l-DAP, was determined at 1.95 Å. Surprisingly, the structure bound to the products revealed that HiDapE undergoes a significant conformational change in which the catalytic domain rotates ∼50° and shifts ∼10.1 Å (as measured at the position of the Zn atoms) relative to the dimerization domain. This heretofore unobserved closed conformation revealed significant movements within the catalytic domain compared to that of wild-type HiDapE, which results in effectively closing off access to the dinuclear Zn(II) active site with the succinate carboxylate moiety bridging the dinculear Zn(II) cluster in a μ-1,3 fashion forming a bis(μ-carboxylato)dizinc(II) core with a Zn-Zn distance of 3.8 Å. Surprisingly, His194.B, which is located on the dimerization domain of the opposing chain ∼10.1 Å from the dinuclear Zn(II) active site, forms a hydrogen bond (2.9 Å) with the oxygen atom of succinic acid bound to Zn2, forming an oxyanion hole. As the closed structure forms upon substrate binding, the movement of His194.B by more than ∼10 Å is critical, based on site-directed mutagenesis data, for activation of the scissile carbonyl carbon of the substrate for nucleophilic attack by a hydroxide nucleophile. Employing the HiDapE product-bound structure as the starting point, a reverse engineering approach called product-based transition-state modeling provided structural models for each major catalytic step. These data provide insight into the catalytic reaction mechanism and also the future design of new, potent inhibitors of DapE enzymes.

Objectives: To evaluate visual outcomes after bilateral implantation of Crystalens accommodative intraocular lenses. Material and methods: The study group consisted of 20 patients (40 eyes) who underwent uneventful phacoemulsification through a 2.8 mm wide clear corneal incision followed by the implantation of an accommodative intraocular lens Crystalens HD or Crystalens AO. Uncorrected visual acuity, best corrected visual acuity, distance corrected intermediate visual acuity, distance corrected near visual acuity, best near visual acuity 1, 3, 6, 12 months postoperatively were evaluated. Distance visual acuity was measured with Snellen test. Near (40 cm) and intermediate (80 cm) visual acuity were measured with Jeager test. Results: The mean uncorrected distance visual acuity was 0.94 and 0.89 at month 1. and 12., respectively. The distance corrected intermediate visual acuity was 0.9 and 0.86 at month 1. and 12., respectively. The distance corrected near visual acuity was J1 in 10% and J3 in 50% of patients at month 1. It was J1 in 10% and J3 in 55% of patients at month 12. Conclusions: Crystalens intraocular lens implantation in our patients enabled them to achieve good distance, near and intermediate visual acuity. The majority of patients did not require spectacle correction for distance and near (87.5% and 65%, respectively). The achieved results did not differ significantly at months 1., 6., and 12. postoperatively.

Binding of the competitive inhibitor L-captopril to the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Neisseria meningitidis (NmDapE) was examined by kinetic, spectroscopic, and crystallographic methods. L-Captopril, an angiotensin-converting enzyme (ACE) inhibitor, was previously shown to be a potent inhibitor of the DapE from Haemophilus influenzae (HiDapE) with an IC50 of 3.3 μM and a measured Ki of 1.8 μM and displayed a dose-responsive antibiotic activity toward Escherichia coli. L-Captopril is also a competitive inhibitor of NmDapE with a Ki of 2.8 μM. To examine the nature of the interaction of L-captopril with the dinuclear active site of DapE, we have obtained electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) data for the enzymatically hyperactive Co(II)-substituted forms of both HiDapE and NmDapE. EPR and MCD data indicate that the two Co(II) ions in DapE are antiferromagnetically coupled, yielding an S = 0 ground state, and suggest a thiolate bridge between the two metal ions. Verification of a thiolate-bridged dinuclear complex was obtained by determining the three-dimensional X-ray crystal structure of NmDapE in complex with L-captopril at 1.8 Å resolution. Combination of these data provides new insights into binding of L-captopril to the active site of DapE enzymes as well as important inhibitor-active site residue interaction's. Such information is critical for the design of new, potent inhibitors of DapE enzymes.

Intraocular lens implantation is an important part of cataract surgery, as it has a significant influence on the final result. Accommodative intraocular lenses (IOLs) are the latest solution for the lack of accommodation in pseudophakic eyes.To evaluate the quality of life of patients who underwent cataract surgery with accommodating IOL implantation and to compare the data with results of patients after standard monofocal IOL implantation.The study group consisted of 20 patients (40 eyes), aged from 48 to 73 years old, who underwent phacoemulsification through a 2.75 mm clear corneal incision followed by the implantation of an accommodating IOL Crystalens HD (BauschLomb, USA). The control group consisted of 20 patients (40 eyes), aged from 63 to 83 years old, who underwent phacoemulsification through a 2.75 mm clear corneal incision followed by the implantation of a standard monofocal single-piece acrylic intraocular lens AcrySof (Alcon, USA). All enrolled patients had no coexisting ocular diseases which could influence the final visual acuity. All surgeries were uneventful. At one month postoperatively, the patients were requested to answer 36 questions included in the questionnaire in order to evaluate the quality of visual function.There was a significant improvement in the quality of life in both groups after cataract surgery. The study group tended to assess their own eyesight higher than the control group. Patients from the study group use spectacle correction for a lower number of activities, they find it easier to use fine motor skills when performing activities without spectacle correction in comparison with patients from the control group. Patients from the study group use spectacle correction for reading significantly less frequently, they also find it easier to read the normal size and small print without spectacle correction, in comparison with patients from the control group.Patients with accommodating IOLs self-evaluate their own eyesight highly, use spectacle correction for a lower number of activities and find it significantly easier to perform precise activities without spectacle correction, in comparison with patients after the standard monofocal intraocular lens implantation.

The emergence of antibiotic-resistant bacterial strains underscores the importance of identifying new drug targets and developing new antimicrobial compounds. Lysine and meso-diaminopimelic acid are essential for protein production and bacterial peptidoglycan cell wall remodeling and are synthesized in bacteria by enzymes encoded within dap operon. Therefore dap enzymes may serve as excellent targets for developing a new class of antimicrobial agents. The dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) converts N-succinyl-L,L-diaminopimelic acid to L,L-diaminopimelic acid and succinate. The enzyme is composed of catalytic and dimerization domains, and belongs to the M20 peptidase family. To understand the specific role of each domain of the enzyme we engineered dimerization domain deletion mutants of DapEs from Haemophilus influenzae and Vibrio cholerae, and characterized these proteins structurally and biochemically. No activity was observed for all deletion mutants. Structural comparisons of wild-type, inactive monomeric DapE enzymes with other M20 peptidases suggest that the dimerization domain is essential for DapE enzymatic activity. Structural analysis and molecular dynamics simulations indicate that removal of the dimerization domain increased the flexibility of a conserved active site loop that may provide critical interactions with the substrate.

"In Mourning and In Rage . . ." was conceived as a response to Leslie and Suzanne's very personal grief and rage over the incidents of rape-murder in Los Angeles which are labeled the "Hillside Strangler Case." After reading about the tenth victim, they decided to design a media event which would include the collaborative participation of women's organizations, city government, and members of the women's community. Seventy women dressed in black gathered at the Woman's Building in Los Angeles. The women received instructions for the event which began when ten actresses dressed in black mourning emerged from the Building and entered a hearse. The hearse and two motorcycle escorts departed from the Building, followed by twenty-two cars filled with women in black. Each car had its lights on and displayed two stickers: "Funeral" and "Stop Violence Against Women." The motorcade circled City Hall twice and stopped in front of the assembled members of the news media. One at a time, nine seven-foot-tall veiled women mourners emerged from the hearse and stood in a line on the sidewalk. The final figure emerged, an active woman clothed in scarlet. The ten women faced the street as the hearse departed while women from the motorcade procession drove slowly past in silent homage to the mourners. Forming a procession three abreast, the mourners walked toward the steps in front of City Hall. Women from the motorcade positioned themselves on either side of the steps forming a black-clothed chorus from a modern tragedy. They unfurled a banner which read "In Memory of Our Sisters, Women Fight Back." As soon as the media had positioned itself to record this second part of the event, the first mourner walked toward the microphone and in a loud, clear voice said "I am here for the ten women who have been raped and strangled between October 18 and November 291" The chorus echoed her with "In memory of our sisters, we fight back!" as she was wrapped with a brilliant red scarf by the woman clothed in red. She took her place on the steps, followed by the second mourner. Each of the nine women made her statement which connected this