The cytidine deaminase APOBEC3C has unique sequence and genome feature preferences.

APOBEC proteins are cytidine deaminases that restrict the replication of viruses and transposable elements. Several members of the APOBEC3 family, APOBEC3A, APOBEC3B, and APOBEC3H-I, can access the nucleus and cause what is thought to be indiscriminate deamination of the genome, resulting in mutagenesis and genome instability. Although APOBEC3C is also present in the nucleus, the full scope of its deamination target preferences is unknown. By expressing human APOBEC3C in a yeast model system, I have defined the APOBEC3C mutation signature, as well as the preferred genome features of APOBEC3C targets. The APOBEC3C mutation signature is distinct from those of the known cancer genome mutators APOBEC3A and APOBEC3B. APOBEC3C produces DNA strand-coordinated mutation clusters, and APOBEC3C mutations are enriched near the transcription start sites of active genes. Surprisingly, APOBEC3C lacks the bias for the lagging strand of DNA replication that is seen for APOBEC3A and APOBEC3B. The unique preferences of APOBEC3C constitute a mutation profile that will be useful in defining sites of APOBEC3C mutagenesis in human genomes.

Design and Rationale of the V-Wave Shunt MitraClip Study.

BACKGROUND: Patients heart failure (HF) and moderate-to-severe mitral regurgitation (MR) with residual elevations in left atrial pressure (LAP) following MitraClip may remain symptomatic and suffer subsequent HF readmissions. The V-Wave Interatrial Shunt System is a permanent interatrial septal implant that shunts blood from the left to right atrium and serves to continuously unload the left atrium. Though the V-Wave shunt has previously been studied in HF patients, the safety and feasibility of its deployment at the time of the MitraClip procedure is unknown. STUDY DESIGN: The V-Wave Shunt MitraClip Study (NCT04729933) is an early feasibility study which aims to demonstrate the safety and efficacy of implantation of the V-Wave shunt device at the time of MitraClip procedure. Patients with moderate-to-severe secondary MR with LVEF 20-50% and NYHA functional class III/IV symptoms despite optimal medical therapy, residual mean left atrial pressure ≥ 20 mmHg after MitraClip, and mean left atrial pressure - right atrial pressure difference ≥ 5 mmHg are included. The primary safety endpoint is a composite outcome of all-cause death, stroke, myocardial infarction device embolization, cardiac tamponade, or device-related re-intervention or surgery at 30-days. Patients will be followed out to 5 years. Enrollment is ongoing, with 30-day results expected by the end of 2024. CONCLUSIONS: The V-Wave Shunt Mitraclip study aims to demonstrate the safety and efficacy of the implantation of the V-Wave interatrial shunt device at the time of index MitraClip placement which may serve as an adjunctive method by which continuous left atrial unloading may be achieved.

The Modified Frailty Index Predicts Major Complications in Oncoplastic Reduction Mammoplasty.

BACKGROUND: An important component of preoperative counseling and patient selection involves surgical risk stratification. There are many tools developed to predict surgical complications. The Modified Frailty Index (mFI) calculates risk based on the following five elements: hypertension, chronic obstructive pulmonary disease, congestive heart failure, diabetes, and functional status. Recent literature demonstrates the efficacy of the mFI across multiple surgical disciplines. We elected to investigate its utility in oncoplastic reductions (OCR). METHODS: A retrospective review of all patients with breast cancer who underwent OCR from 1998 to 2020 was queried from a prospectively maintained database. Patient demographics, comorbidities, and surgical details were reviewed. The mFI was computed for each patient. The primary clinical outcome was the development of complications. RESULTS: 547 patients were included in the study cohort. The average age was 55 and the average body mass index was 33.5. The overall complication rate was 19% (n = 105) and the major complication rate was 9% (n = 49). Higher frailty scores were significantly associated with the development of major complications (P < 0.05). mFI scores of 0 had a major complication rate of 5.7%; scores of 1, 13%; and scores of 2, 15.1%. The relative risk of a major complication in patients with elevated mFI (>0) was 2.2. Age, body mass index, and resection weights were not associated with complications (P = 0.15, P = 0.87, and P = 0.30 respectively) on continuous analysis. CONCLUSIONS: Elevated mFI scores are associated with an increased major complication profile in patients who are undergoing OCR. Hypertension and diabetes are the most common comorbidities in our population, and this tool may assist with preoperative counseling and risk stratification. Benefits of this risk assessment tool include its ease of calculation and brevity. Our study is the first to demonstrate its utility in OCR; however, further study in high-risk patients would strengthen the applicability of this frailty index.

Periareolar Skin-Sparing Mastectomy and Immediate Implant-Based Reconstruction: A Reappraisal.

INTRODUCTION: Skin-sparing mastectomy (SSM) is often used when tumor location prohibits performing a nipple-sparing mastectomy (NSM). We examined a square excision of the nipple-areolar complex (NAC) and an X-shaped purse string closure after implant-based reconstruction. METHODS: A retrospective review was performed on patients undergoing periareolar SSM and immediate implant-based reconstruction from January 2015 through December 2022, specifically identifying those patients who had square NAC excision and skin closure. RESULTS: Twenty-nine patients met the inclusion criteria. They underwent 54 periareolar SSM and immediate implant-based reconstruction (bilateral 25, unilateral 4). Indications for surgery were cancer (30) and prophylactic (24; 2 patients had bilateral cancer). Reconstructive methods included tissue expander (TE) (36 [66.7%]) and direct-to-implant (DTI) (18 [33.3%]). The mean mastectomy weights and final implant sizes were similar between the 2 groups. Overall wound complications occurred in 13 (24.1%) of the breasts: mastectomy skin flap necrosis (MSFN; 10 [18.5%]) and infection (3 [5.6%]). Reconstructive failure occurred in 3 cases: TE, 1 (infection); DTI, 2 (MSFN/exposure). MSFN by reconstructive method: TE, 4 (11.1%); DTI, 6 (33.3%) (P = 0.05, comparing MSFN rates between TE and DTI methods). The mean initial TE fill volume was 247.1 cc; mean implant size in the DTI group was 417.8 cc (P < 0.0001). CONCLUSIONS: The square NAC excision and closure can minimize the surgical incision in implant reconstruction. Two-stage TE reconstruction permits lower initial fill volumes, which reduces the risk of MSFN after box to X closure of SSM and implant-based reconstruction. It is useful in small- to moderate-sized breasts with mild ptosis in patients who are not candidates for NSM.

AAP Recommended Cardiac Screening Questions in Preparticipation Physical Evaluation Forms.

To evaluate the utilization of the American Academy of Pediatrics' (AP) cardiovascular screening questions within preparticipation physical evaluation forms from the 50 state high school athletic associations. We found that fewer than half of state forms incorporated all 10 AAP questions; moreover, a subset failed to adhere to criteria recommended by either the AAP or American Heart Association.

Urothelium-derived prostanoids enhance contractility of urinary bladder smooth muscle and stimulate bladder afferent nerve activity in the mouse.

The transitional epithelial cells (urothelium) that line the lumen of the urinary bladder form a barrier between potentially harmful pathogens, toxins, and other bladder contents and the inner layers of the bladder wall. The urothelium, however, is not simply a passive barrier, as it can produce signaling factors, such as ATP, nitric oxide, prostaglandins, and other prostanoids, that can modulate bladder function. We investigated whether substances produced by the urothelium could directly modulate the contractility of the underlying urinary bladder smooth muscle. Force was measured in isolated strips of mouse urinary bladder with the urothelium intact or denuded. Bladder strips developed spontaneous tone and phasic contractions. In urothelium-intact strips, basal tone, as well as the frequency and amplitude of phasic contractions, were 25%, 32%, and 338% higher than in urothelium-denuded strips, respectively. Basal tone and phasic contractility in urothelium-intact bladder strips were abolished by the cyclooxygenase (COX) inhibitor indomethacin (10 µM) or the voltage-dependent Ca2+ channel blocker diltiazem (50 µM), whereas blocking neuronal sodium channels with tetrodotoxin (1 µM) had no effect. These results suggest that prostanoids produced in the urothelium enhance smooth muscle tone and phasic contractions by activating voltage-dependent Ca2+ channels in the underlying bladder smooth muscle. We went on to demonstrate that blocking COX inhibits the generation of transient pressure events in isolated pressurized bladders and greatly attenuates the afferent nerve activity during bladder filling, suggesting that urothelial prostanoids may also play a role in sensory nerve signaling.NEW & NOTEWORTHY This paper provides evidence for the role of urothelial-derived prostanoids in maintaining tone in the urinary bladder during bladder filling, not only underscoring the role of the urothelium as more than a barrier but also contributing to active regulation of the urinary bladder. Furthermore, cyclooxygenase products greatly augment sensory nerve activity generated by bladder afferents during bladder filling and thus may play a role in perception of bladder fullness.

Comparison of Contemporary Treatment Strategies in Patients With Cardiogenic Shock Due to Severe Aortic Stenosis.

BACKGROUND: The aims of this study were to understand the incidence and outcomes of patients with cardiogenic shock (CS) due to severe aortic stenosis (AS), and the impact of conventional treatment strategies in this population. METHODS AND RESULTS: All patients admitted to the Cleveland Clinic cardiac intensive care unit between January 1, 2010 and December 31, 2021 with CS were retrospectively identified and categorized into those with CS in the setting of severe AS versus CS without AS. The impact of various treatment strategies on mortality was further assessed. We identified 2754 patients with CS during the study period, of whom 216 patients (8%) had CS in the setting of severe AS. Medical management was associated with the highest 30-day mortality when compared with either balloon aortic valve replacement or aortic valve replacement (surgical or transcatheter aortic valve replacement) (hazard ratio, 3.69 [95% CI, 2.04-6.66]; P<0.0001). Among patients who received transcatheter therapy, 30-day mortality was significantly higher in patients who received balloon aortic valvuloplasty versus transcatheter aortic valve replacement (26% versus 4%, P=0.02). Both surgical and transcatheter aortic valve replacement had considerably lower mortality than medical management and balloon aortic valvuloplasty at 30 days and 1 year (P<0.05 for both comparisons). CONCLUSIONS: CS due to severe AS is associated with high in-hospital and 30-day mortality, worse compared with those with CS without AS. In suitable patients, urgent surgical aortic valvuloplasty or transcatheter aortic valve replacement is associated with favorable short- and long-term outcomes. Although balloon aortic valvuloplasty may be used to temporize patients with CS in the setting of severe AS, mortality is ≈50% if not followed by definitive aortic valve replacement within 90 days.

Antibodies to Malondialdehyde-Acetaldehyde Adduct Are Associated With Prevalent and Incident Rheumatoid Arthritis-Associated Interstitial Lung Disease in US Veterans.

OBJECTIVE: The objective of this study is to determine the associations of protein-specific anti-malondialdehyde-acetaldehyde (MAA) antibodies with prevalent and incident rheumatoid arthritis-interstitial lung disease (RA-ILD). METHODS: Within a multicenter, prospective cohort of US veterans with RA, RA-ILD was validated by medical record review of clinical diagnoses, chest imaging, and pathology. Serum antibodies to MAA-albumin, MAA-collagen, MAA-fibrinogen, and MAA-vimentin (IgA, IgM, and IgG) were measured by a standardized enzyme-linked immunosorbent assay. Associations of anti-MAA antibodies with prevalent and incident RA-ILD were assessed using multivariable regression models adjusting for established RA-ILD risk factors. RESULTS: Among 2,739 participants with RA (88% male, mean age of 64 years), there were 114 with prevalent and 136 with incident RA-ILD (average time to diagnosis: 6.6 years). Higher IgM anti-MAA-collagen (per 1 SD: adjusted odds ratio [aOR] 1.28, 95% confidence interval [CI] 1.02-1.61), IgA anti-MAA-fibrinogen (aOR 1.48, 95% CI 1.14-1.92), and IgA (aOR 1.78, 95% CI 1.34-2.37) and IgG (aOR 1.48, 95% CI 1.14-1.92) anti-MAA-vimentin antibodies were associated with prevalent RA-ILD. In incident analyses, higher IgA (per one SD: adjusted hazards ratio [aHR] 1.40, 95% CI 1.11-1.76) and IgM (aHR 1.29, 95% CI 1.04-1.60) anti-MAA-albumin antibody concentrations were associated with increased ILD risk. Participants with IgA (aHR 2.13, 95% CI 1.16-3.90) or IgM (aHR 1.98, 95% CI 1.08-3.64) anti-MAA-albumin antibody concentrations in the highest quartile had an approximately two-fold increased risk of incident RA-ILD. Across all isotypes, anti-MAA-fibrinogen, anti-MAA-collagen, and anti-MAA-vimentin antibodies were not significantly associated with incident RA-ILD. CONCLUSION: Protein-specific anti-MAA antibodies to collagen, fibrinogen, and vimentin were associated with prevalent RA-ILD. IgA and IgM anti-MAA-albumin antibodies were associated with a higher risk of incident RA-ILD. These findings suggest that MAA modifications and resultant immune responses may contribute to RA-ILD pathogenesis.

Role of aortic valve replacement in moderate aortic stenosis: a 10-year outcomes study.

OBJECTIVE: Patients with moderate aortic stenosis (AS) exhibit high morbidity and mortality. Limited evidence exists on the role of aortic valve replacement (AVR) in this patient population. To investigate the benefit of AVR in moderate AS on survival and left ventricular function. METHODS: In a retrospective cohort study, patients with moderate AS between 2008 and 2016 were selected from the Cleveland Clinic echocardiography database and followed until 2018. Patients were classified as receiving AVR or managed medically (clinical surveillance). All-cause and cardiovascular mortality were assessed by survival analyses. Temporal haemodynamic and structural changes were assessed with longitudinal analyses using linear mixed effects models. RESULTS: We included 1421 patients (mean age, 75.3±5.4 years and 39.9% women) followed over a median duration of 6 years. Patients in the AVR group had lower risk of all-cause (adjusted HR (aHR)=0.51, 95% CI: 0.34 to 0.77; p=0.001) and cardiovascular mortality (aHR=0.50, 95% CI: 0.31 to 0.80; p=0.004) compared with those in the clinical surveillance group irrespective of sex, receipt of other open-heart surgeries and underlying malignancy. These findings were seen only in those with preserved left ventricular ejection fraction (LVEF) ≥50%. Further, patients in the AVR group had a significant trend towards an increase in LVEF and a decrease in right ventricular systolic pressure compared with those in the clinical surveillance group. CONCLUSIONS: In patients with moderate AS, AVR was associated with favourable clinical outcomes and left ventricular remodelling.

Missed opportunities for treatment of inflammatory arthritis and factors associated with non-treatment: An observational cohort study in United States Veterans with rheumatoid arthritis, psoriatic arthritis, or ankylosing spondylitis.

OBJECTIVE: To identify factors associated with non-treatment with biologic and non-biologic disease modifying anti-rheumatic drugs (DMARDs) during the 12 months after initial inflammatory arthritis (IA) diagnosis. METHODS: We identified Veterans with incident IA diagnosed in 2007-2019. We assessed time to treatment with Kaplan-Meier curves. We identified associations between non-treatment and factors relating to patients, providers, and the health system with multivariate Generalized Estimation Equation (GEE) log-Poisson. Subgroup analyses included IA subtypes (rheumatoid arthritis [RA], psoriatic arthritis [PsA], and ankylosing spondylitis [AS]) and timeframes of the initial IA diagnosis (2007-11, 2012-15, and 2016-19). RESULTS: Of 18,318 study patients, 40.7 % did not receive treatment within 12 months after diagnosis. In all patients, factors associated with non-treatment included Black race (hazard ratio, 95 % confidence interval: 1.13, 1.08-1.19), Hispanic ethnicity (1.14, 1.07-1.22), Charlson Comorbidity Index ≥2, (1.15, 1.11-1.20), and opiate use (1.09, 1.05-1.13). Factors associated with higher frequency of DMARD treatment included married status (0.86, 0.81-0.91); erosion in joint imaging report (HR: 0.86, 0.81-0.91); female diagnosing provider (0.90, CI: 0.85-0.96), gender concordance between patient and provider (0.91, CI: 0.86-0.97), and diagnosing provider specialty of rheumatology (0.53, CI: 0.49-0.56). CONCLUSION: A high proportion of Veterans with IA were not treated with a biologic or non-biologic DMARD within one year after their initial diagnosis. A wide range of factors were associated with non-treatment of IA that may represent missed opportunities for improving the quality of care through early initiation of DMARDs.

The emerging importance of skull-brain interactions in traumatic brain injury.

The recent identification of skull bone marrow as a reactive hematopoietic niche that can contribute to and direct leukocyte trafficking into the meninges and brain has transformed our view of this bone structure from a solid, protective casing to a living, dynamic tissue poised to modulate brain homeostasis and neuroinflammation. This emerging concept may be highly relevant to injuries that directly impact the skull such as in traumatic brain injury (TBI). From mild concussion to severe contusion with skull fracturing, the bone marrow response of this local myeloid cell reservoir has the potential to impact not just the acute inflammatory response in the brain, but also the remodeling of the calvarium itself, influencing its response to future head impacts. If we borrow understanding from recent discoveries in other CNS immunological niches and extend them to this nascent, but growing, subfield of neuroimmunology, it is not unreasonable to consider the hematopoietic compartment in the skull may similarly play an important role in health, aging, and neurodegenerative disease following TBI. This literature review briefly summarizes the traditional role of the skull in TBI and offers some additional insights into skull-brain interactions and their potential role in affecting secondary neuroinflammation and injury outcomes.

Outcomes and treatment strategy of transcatheter aortic valve replacement with balloon-expandable valve in borderline-size annulus.

BACKGROUND: Candidates for transcatheter aortic valve replacement (TAVR) occasionally have a "borderline-size" aortic annulus between 2 transcatheter heart valve sizes, based on the manufacturer's sizing chart. Data on TAVR outcomes in such patients are limited. METHODS: We retrospectively reviewed 1816 patients who underwent transfemoral-TAVR with balloon-expandable valve (BEV) at our institution between 2016 and 2020. We divided patients into borderline and non-borderline groups based on computed tomography-derived annular measurements and compared outcomes. Furthermore, we analyzed procedural characteristics and compared outcomes between the smaller- and larger-valve strategies in patients with borderline-size annulus. RESULTS: During a median follow-up of 23.3 months, there was no significant difference between the borderline (n = 310, 17.0 %) and non-borderline (n = 1506) groups in mortality (17.3 % vs. 19.5 %; hazard ratio [HR] = 0.86 [95% CI = 0.62-1.20], p = 0.39), major adverse cardiac/cerebrovascular events (MACCE: death/myocardial infarction/stroke, 21.2 % vs. 21.5 %; HR = 0.97 [0.71-1.32], p = 0.85), paravalvular leak (PVL: mild 21.8 % vs. 20.6 %, p = 0.81; moderate 0 % vs. 1.2 %; p = 0.37), or mean gradient (12.9 ± 5.8 vs. 12.6 ± 5.2 mmHg, p = 0.69) at 1 year. There was no significant difference between the larger-(n = 113) and smaller-valve(n = 197) subgroups in mortality (23.7 % vs. 15.2 %; HR = 1.57 [0.89-2.77], p = 0.12), MACCE (28.1 % vs. 18.4 %; HR = 1.52 [0.91-2.54], p = 0.11), mild PVL (13.3 % vs. 25.9 %; p = 0.12), or mean gradient (12.3 ± 4.5 vs. 13.6 ± 5.3 mmHg, p = 0.16); however, the rate of permanent pacemaker implantation (PPI) was higher in the larger-valve subgroup (15.9 % vs. 2.6 %, p < 0.001). CONCLUSION: Borderline-size annulus is not associated with higher risk of adverse outcomes after BEV-TAVR. However, the larger-valve strategy for borderline-size annulus is associated with higher PPI risk, suggesting a greater risk of injury to the conduction system.

A conserved function of corepressors is to nucleate assembly of the transcriptional preinitiation complex.

The plant corepressor TPL is recruited to diverse chromatin contexts, yet its mechanism of repression remains unclear. Previously, we have leveraged the fact that TPL retains its function in a synthetic transcriptional circuit in the yeast model Saccharomyces cerevisiae to localize repressive function to two distinct domains. Here, we employed two unbiased whole genome approaches to map the physical and genetic interactions of TPL at a repressed locus. We identified SPT4, SPT5 and SPT6 as necessary for repression with the SPT4 subunit acting as a bridge connecting TPL to SPT5 and SPT6. We also discovered the association of multiple additional constituents of the transcriptional preinitiation complex at TPL-repressed promoters, specifically those involved in early transcription initiation events. These findings were validated in yeast and plants through multiple assays, including a novel method to analyze conditional loss of function of essential genes in plants. Our findings support a model where TPL nucleates preassembly of the transcription activation machinery to facilitate rapid onset of transcription once repression is relieved.

Dosimetric and toxicity comparison between Syed-Neblett and Fletcher-Suit-Delclos Tandem and Ovoid applicators in high dose rate cervix cancer brachytherapy.

PURPOSE: To compare patient and tumor characteristics, dosimetry, and toxicities between interstitial Syed-Neblett and intracavitary Fletcher-Suit-Delclos Tandem and Ovoid (T&O) applicators in high dose rate (HDR) cervical cancer brachytherapy. METHODS: A retrospective analysis was performed for cervical cancer patients treated with 3D-based HDR brachytherapy from 2011 to 2023 at a single institution. Dosimetric parameters for high-risk clinical target volume and organs at risk were obtained. Toxicities were evaluated using the Common Terminology Criteria for Adverse Events version 5.0. RESULTS: A total of 115 and 58 patients underwent Syed and T&O brachytherapy, respectively. Patients treated with Syed brachytherapy were more likely to have larger tumors and FIGO stage III or IV disease. The median D2cc values to the bladder, small bowel, and sigmoid colon were significantly lower for Syed brachytherapy. Patients treated with Syed brachytherapy were significantly more likely to be free of acute gastrointestinal (44% vs. 21%, p = 0.003), genitourinary (58% vs. 36%, p = 0.01), and vaginal toxicities (60% vs. 33%, p = 0.001) within 6 months following treatment compared to patients treated with T&O applicators. In contrast, Syed brachytherapy patients were more likely to experience late gastrointestinal (68% vs. 49%, p = 0.082), genitourinary (51% vs. 35%, p = 0.196), and vaginal toxicities (70% vs. 57%, p = 0.264). CONCLUSIONS: Syed-Neblett and T&O applicators are suitable for HDR brachytherapy for cervical cancer in distinct patient populations. Acute toxicities are more prevalent with T&O applicators, while patients treated with Syed-Neblett applicators are more likely to develop late toxicities.

Aetiology and predictors of major bleeding events in patients with heart failure with reduced ejection fraction undergoing percutaneous coronary intervention.

OBJECTIVES: We sought to determine the relationship between the degree of left ventricular ejection fraction (LVEF) impairment and the frequency and type of bleeding events after percutaneous coronary intervention (PCI). DESIGN: This was an observational retrospective cohort analysis. Patients who underwent PCI from 2009 to 2017 were identified from our institutional National Cardiovascular Disease Registry (NCDR) CathPCI database. Patients were stratified by pre-PCI LVEF: preserved (≥50%), mildly reduced (41%-49%) and reduced (≤40%) LVEF. PRIMARY OUTCOME MEASURES: The outcome was major bleeding, defined by NCDR criteria. Events were classified based on bleeding aetiology and analysed by multivariable logistic regression. RESULTS: Among 13 537 PCIs, there were 817 bleeding events (6%). The rate of bleeding due to any cause, blood transfusion, gastrointestinal bleeding and coronary artery perforation or tamponade each increased in a stepwise fashion comparing preserved, mildly reduced and reduced LVEF reduction (p<0.05 for all comparisons). However, there were no differences in bleeding due to asymptomatic drops in haemoglobin, access site haematoma or retroperitoneal bleeding. After multivariable adjustment, mildly reduced and reduced LVEF remained independent predictors of bleeding events (OR 1.36, 95% CI 1.06 to 1.74, p<0.05 and OR 1.73, 95% CI 1.45 to 2.06, p<0.0001). CONCLUSIONS: The degree of LV dysfunction is an independent predictor of post-PCI major bleeding events. Patients with mildly reduced or reduced LVEF are at greatest risk of post-PCI bleeding, driven by an increased need for blood transfusion, major GI bleeding events and coronary artery perforation or tamponade. Pre-PCI LV dysfunction does not predict asymptomatic declines in haemoglobin, access site haematoma or retroperitoneal bleeding.

Cytidine deaminases APOBEC3C and APOBEC3D promote DNA replication stress resistance in pancreatic cancer cells.

Gemcitabine is a potent inhibitor of DNA replication and is a mainstay therapeutic for diverse cancers, particularly pancreatic ductal adenocarcinoma (PDAC). However, most tumors remain refractory to gemcitabine therapies. Here, to define the cancer cell response to gemcitabine, we performed genome-scale CRISPR-Cas9 chemical-genetic screens in PDAC cells and found selective loss of cell fitness upon disruption of the cytidine deaminases APOBEC3C and APOBEC3D. Following gemcitabine treatment, APOBEC3C and APOBEC3D promote DNA replication stress resistance and cell survival by deaminating cytidines in the nuclear genome to ensure DNA replication fork restart and repair in PDAC cells. We provide evidence that the chemical-genetic interaction between APOBEC3C or APOBEC3D and gemcitabine is absent in nontransformed cells but is recapitulated across different PDAC cell lines, in PDAC organoids and in PDAC xenografts. Thus, we uncover roles for APOBEC3C and APOBEC3D in DNA replication stress resistance and offer plausible targets for improving gemcitabine-based therapies for PDAC.

Techniques in Nipple Areolar Reconstruction: A Retrospective Analysis of Surgical Interventions and Patient-reported Satisfaction Scores.

Background: Nipple areolar complex (NAC) reconstruction often signifies completion of the breast reconstruction process for some patients and has been shown to improve both psychosocial and sexual well-being. Several techniques have been described; however, there currently exists little evidence in the literature describing outcomes or patient satisfaction. Methods: A retrospective analysis of NAC reconstructions over the last decade was queried for patient demographics, operative technique, and postoperative outcomes. A standardized, validated survey was also utilized to evaluate overall satisfaction, with a focus on aesthetic outcome, shape, color, and projection. Results: Eighty-three patients were identified, with 49 (59.0%) completing the survey. The modalities used for reconstruction include the C-V flap (45.7%), the modified skate flap technique (42.2%), and free nipple grafting (FNG, 12.0%). No significant differences in age, BMI, or comorbidities were found among the three types. The most utilized donor site for skate flap reconstruction was the suprapubic area (37.1%). There were also no significant differences in complication rate (C-V 10.5%, FNG 10%, skate 5.7%, P = 0.630) or revision surgery (C-V 2.6%, FNG 0%, skate 5.7%, P = 0.732). The most common complication was nipple necrosis. Adjusting for time to follow-up using multivariate analysis, there was a significant difference in overall patient satisfaction when compared across all three techniques, with the modified skate flap having the highest mean overall satisfaction scores. Conclusions: NAC reconstruction can be completed safely and effectively with a variety of techniques. The modified skate flap technique was associated with high levels of patient satisfaction and a low complication rate.

A phase I clinical trial assessing the safety, tolerability, and pharmacokinetics of inhaled ethanol in humans as a potential treatment for respiratory tract infections.

Background: Current treatments for respiratory infections are severely limited. Ethanol's unique properties including antimicrobial, immunomodulatory, and surfactant-like activity make it a promising candidate treatment for respiratory infections if it can be delivered safely to the airway by inhalation. Here, we explore the safety, tolerability, and pharmacokinetics of inhaled ethanol in a phase I clinical trial. Methods: The study was conducted as a single-centre, open-label clinical trial in 18 healthy adult volunteers, six with no significant medical comorbidities, four with stable asthma, four with stable cystic fibrosis, and four active smokers. A dose-escalating design was used, with participants receiving three dosing cycles of 40, 60%, and then 80% ethanol v/v in water, 2 h apart, in a single visit. Ethanol was nebulised using a standard jet nebuliser, delivered through a novel closed-circuit reservoir system, and inhaled nasally for 10 min, then orally for 30 min. Safety assessments included adverse events and vital sign monitoring, blood alcohol concentrations, clinical examination, spirometry, electrocardiogram, and blood tests. Results: No serious adverse events were recorded. The maximum blood alcohol concentration observed was 0.011% immediately following 80% ethanol dosing. Breath alcohol concentrations were high (median 0.26%) following dosing suggesting high tissue levels were achieved. Small transient increases in heart rate, blood pressure, and blood neutrophil levels were observed, with these normalising after dosing, with no other significant safety concerns. Of 18 participants, 15 completed all dosing cycles with three not completing all cycles due to tolerability. The closed-circuit reservoir system significantly reduced fugitive aerosol loss during dosing. Conclusion: These data support the safety of inhaled ethanol at concentrations up to 80%, supporting its further investigation as a treatment for respiratory infections.Clinical trial registration: identifier ACTRN12621000067875.