Faculty Bibliography

BACKGROUND:Staged implant-based breast reconstruction is the most common reconstructive modality following mastectomy. Postoperative implant infections can have a significant impact on adjuvant oncologic care and reconstructive outcome. Here, we investigate the impact of β-lactam antibiotics (i.e., bactericidal) compared to alternative antibiotic agents on postoperative outcomes for implant-based breast reconstruction. METHODS:A retrospective analysis of patients who underwent immediate sub-pectoral tissue expander placement with an inferior acellular dermal matrix (ADM) sling at a single institution between May 2008 and July 2018 was performed. Patient demographics, comorbidities, and complication rates were retrieved. The impact of antibiotic regimen on postoperative outcomes, including infection rate and reconstructive failure, was investigated. RESULTS:, respectively, who underwent 542 immediate breast reconstructions were included in the study. The use of a β-lactam antibiotic was protective against postoperative infection (odds ratio [OR] = 0.467, p = .046), infection requiring operative management (OR = 0.313, p = .022), and reconstructive failure (OR = 0.365, p = .028). Extended, that is, post-discharge, prophylaxis was not associated with any clinical benefit. CONCLUSION/CONCLUSIONS:The use of β-lactam antibiotics for pre-/peri-operative prophylaxis is superior to alternative antibiotics with a bacteriostatic mechanism of action regarding rates of postoperative infection and reconstructive failure following immediate tissue expander-based breast reconstruction. Extended, that is, post-discharge, prophylaxis does not appear to be indicated, regardless of the antibiotic chosen.

BACKGROUND:With the exponential increase in the use of endovascular techniques in the treatment of peripheral artery disease, our understanding of factors that affect intervention failures continues to grow. We sought to assess the outcomes of percutaneous transluminal angioplasty for isolated de novo superficial femoral artery (SFA) disease based on balloon diameter. METHODS:The Vascular Quality Initiative database was queried for patients undergoing percutaneous balloon angioplasty for isolated de novo atherosclerotic SFA disease. Based on the diameter of the angioplasty balloon as a surrogate measure of arterial diameter, patients were stratified into two groups: group 1, balloon diameter < 5 mm (354 patients) and group 2, balloon diameter ≥ 5 mm (1,550 patients). The primary patency and major adverse limb event (MALE) were estimated by the Kaplan-Meier method and compared with the log-rank test, based on vessel diameter. multivariable Cox regression analysis was used to determine factors associated with the primary patency. RESULTS:From January 2010 through December 2018, a total of 1,904 patients met criteria for analysis, with a mean follow-up of 13.3 ± 4.5 months. The mean balloon diameters were 3.92 ± 0.26 mm and 5.47 ± 0.55 mm in group 1 and 2, respectively (P<.001). The mean length of treatment and distribution of TASC lesions were not statistically different between the groups. Primary patency at 18 months was significantly lower in group 1, compared with group 2 (55% vs 67%; log-rank P<.001). The MALE rate was higher in group 1 than group 2 (33% vs 26%; log-rank P<.001). Among patients with claudication, there was no significant difference in the primary patency (61% vs 68%; log-rank P=.073) and MALE (27% vs 22%; log-rank P=.176) at 18 months between groups 1 and 2, respectively. However, in patients with CLTI, group 1 had significantly lower 18-month primary patency (47% vs 64%; log-rank P<.014) and higher MALE rates (41% vs 35%; log-rank P=.012) than group 2. Cox proportional hazard analysis confirmed that balloon diameter < 5 mm was independently associated with increased risks of primary patency loss (HR 1.35; 95% CI, 1.04-1.72; P=.021) and MALE (HR 1.29; 95% CI, 1-1.67; P=.048) at 18-months. CONCLUSIONS:In patients undergoing isolated SFA balloon angioplasty for CLTI, smaller SFA (< 5mm) was associated with worse primary patency and MALE. Using balloon size as a surrogate, our findings suggest that patients with a smaller SFA diameter appear to be at increased risk for treatment failure and warrant closer surveillance. Furthermore, these patients may also be considered for alternative approaches, including open revascularization.

BACKGROUND:The association between isotretinoin and psychiatric disturbance, including depression and suicidal behavior, is controversial. OBJECTIVE:To investigate whether acne patients prescribed isotretinoin or antibiotics were more likely to have psychiatric disorders and/or engage in suicidal behavior. METHODS:Retrospective cohort study identified acne patients prescribed isotretinoin or oral antibiotics in the IBM® MarketScan® Databases of commercial US insurance claims data from 2011-2017 who were also diagnosed with psychiatric disorders or suicidal behavior. RESULTS:A total of 72,555 patients were included. Compared to acne patients prescribed isotretinoin, patients in the general population were 1.47 times more likely to be diagnosed with suicidal ideation or attempt (adjusted OR 1.47; 1.27, 1.70, p <.0001). However, the general population (adjusted OR 0.87; 0.84, 0.89, p<0.0001) and acne patients prescribed antibiotics (adjusted OR 0.88; 0.85, 0.91, p<0.0001) were less likely to have a psychiatric diagnosis compared to acne patients prescribed isotretinoin. The prevalence of suicidal behavior during isotretinoin treatment was lower (0.10%) (p=0.082), than during the year prior to (0.22%) and during the year after isotretinoin treatment (0.34%), (p = 0.004). LIMITATIONS/CONCLUSIONS:Study excludes individuals with public or no insurance and relies on physician coding accuracy. CONCLUSIONS:Compared to the general population, acne patients prescribed isotretinoin were less likely to engage in suicidal behavior. Further exploration is warranted into the slight increase in suicidal behavior seen in isotretinoin patients one year after therapy.

Organ function relies on the spatial organization and functional coordination of numerous cell types. The Drosophila ovary is a widely used model system to study the cellular activities underlying organ function, including stem cell regulation, cell signaling and epithelial morphogenesis. However, the relative paucity of cell type-specific reagents hinders investigation of molecular functions at the appropriate cellular resolution. Here, we used single-cell RNA sequencing to characterize all cell types of the stem cell compartment and early follicles of the Drosophila ovary. We computed transcriptional signatures and identified specific markers for nine states of germ cell differentiation and 23 somatic cell types and subtypes. We uncovered an unanticipated diversity of escort cells, the somatic cells that directly interact with differentiating germline cysts. Three escort cell subtypes reside in discrete anatomical positions and express distinct sets of secreted and transmembrane proteins, suggesting that diverse micro-environments support the progressive differentiation of germ cells. Finally, we identified 17 follicle cell subtypes and characterized their transcriptional profiles. Altogether, we provide a comprehensive resource of gene expression, cell type-specific markers, spatial coordinates, and functional predictions for 34 ovarian cell types and subtypes.

Arrhythmogenic cardiomyopathy (ACM) is a familial disease, with approximately 60% of patients displaying a pathogenic variant. The majority of genes linked to ACM code for components of the desmosomes: plakophilin-2 (PKP2), desmoglein-2 (DSG2) and desmocollin-2 (DSC2), plakoglobin (JUP) and desmoplakin (DSP). Genetic variants involving the desmosomes are known to cause dysfunction of cell-to-cell adhesions and intercellular gap junctions. In turn, this may result in failure to mechanically hold together the cardiomyocytes, fibrofatty myocardial replacement, cardiac conduction delay and ventricular arrhythmias. It is becoming clearer that pathogenic variants in desmosomal genes such as PKP2 are not only responsible for a mechanical dysfunction of the intercalated disc (ID), but are also the cause of various pro-arrhythmic mechanisms. In this review, we discuss in detail the different molecular interactions associated with desmosomal pathogenic variants, and their contribution to various ACM phenotypes.

Ire1 is an endoplasmic reticulum (ER) transmembrane RNase that cleaves substrate mRNAs to help cells adapt to ER stress. Because there are cell types with physiological ER stress, loss of Ire1 results in metabolic and developmental defects in diverse organisms. In Drosophila, Ire1 mutants show developmental defects at early larval stages and in pupal eye photoreceptor differentiation. These Drosophila studies relied on a single Ire1 loss of function allele with a Piggybac insertion in the coding sequence. Here, we report that an Ire1 allele with a specific impairment in the RNase domain, H890A, unmasks previously unrecognized Ire1 phenotypes in Drosophila eye pigmentation. Specifically, we found that the adult eye pigmentation is altered, and the pigment granules are compromised in Ire1^H890A homozygous mosaic eyes. Furthermore, the Ire1^H890A mutant eyes had dramatically reduced Rhodopsin-1 protein levels. Drosophila eye pigment granules are most notably associated with late endosome/lysosomal defects. Our results indicate that the loss of Ire1, which would impair ER homeostasis, also results in altered adult eye pigmentation.

Traumatic brain injury (TBI) is a risk factor for the later development of neurodegenerative diseases that may have various underlying pathologies. Chronic traumatic encephalopathy (CTE) in particular is associated with repetitive mild TBI (mTBI) and is characterized pathologically by aggregation of hyperphosphorylated tau into neurofibrillary tangles (NFTs). CTE may be suspected when behavior, cognition, and/or memory deteriorate following repetitive mTBI. Exposure to blast overpressure from improvised explosive devices (IEDs) has been implicated as a potential antecedent for CTE amongst Iraq and Afghanistan Warfighters. In this study, we identified biomarker signatures in rats exposed to repetitive low-level blast that develop chronic anxiety-related traits and in human veterans exposed to IED blasts in theater with behavioral, cognitive, and/or memory complaints. Rats exposed to repetitive low-level blasts accumulated abnormal hyperphosphorylated tau in neuronal perikarya and perivascular astroglial processes. Using positron emission tomography (PET) and the [¹⁸F]AV1451 (flortaucipir) tau ligand, we found that five of 10 veterans exhibited excessive retention of [¹⁸F]AV1451 at the white/gray matter junction in frontal, parietal, and temporal brain regions, a typical localization of CTE tauopathy. We also observed elevated levels of neurofilament light (NfL) chain protein in the plasma of veterans displaying excess [¹⁸F]AV1451 retention. These findings suggest an association linking blast injury, tauopathy, and neuronal injury. Further study is required to determine whether clinical, neuroimaging, and/or fluid biomarker signatures can improve the diagnosis of long-term neuropsychiatric sequelae of mTBI.