Lentiviral Vector Preparation for Efficient Gene and MicroRNA Modulation of Peritoneal Cavity Tissue-Resident Macrophages In Vivo in Mice.

Peritoneal tissue-resident macrophages have broad functions in the maintenance of homeostasis and are involved in pathologies within local and neighboring tissues. Their functions are dictated by microenvironmental cues; thus, it is essential to investigate their behavior in an in vivo physiological niche. Currently, specific peritoneal macrophage-targeting methodologies employ whole-mouse transgenic models.

Modest changes in Spi1 dosage reveal the potential for altered microglial function as seen in Alzheimer's disease.

Genetic association studies have identified multiple variants at the SPI1 locus that modify risk and age of onset for Alzheimer's Disease (AD). Reports linking risk variants to gene expression suggest that variants denoting higher SPI1 expression are likely to have an earlier AD onset, and several other AD risk genes contain PU.1 binding sites in the promoter region.

Craniofacial and Long Bone Development in the Context of Distraction Osteogenesis.

Background: Bone retains regenerative potential into adulthood, and surgeons harness this plasticity during distraction osteogenesis. The underlying biology governing bone development, repair, and regeneration is divergent between the craniofacial and appendicular skeleton. Each type of bone formation is characterized by unique molecular signaling and cellular behavior.

Virtual Interviews in the Era of COVID-19: A Primer for Applicants.

Problem: The COVID-19 pandemic is an evolving crisis with widespread impact upon our medical system, including senior trainee travel for fellowship interviews. Numerous institutions have conscientiously deferred in-person interviews or virtual formats. Given the competitive nature of fellowship interviews, candidates may express concern that they are at a disadvantage in engaging in online meetings versus live, on-site interviews, and similarly may feel ill prepared to perform optimally during online interviews.

More Is Less: The Advantages of Performing Concurrent Laparoscopic Cholecystectomy and Endoscopic Retrograde Cholangiopancreatography for Pediatric Choledocholithiasis.

Endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic cholecystectomy (LC) are standard of care for pediatric choledocholithiasis. Patients typically undergo separate procedures during hospitalization. Collaboration between surgical and gastroenterology services led to performance of both procedures concurrently during one anesthetic.

An investigation of social determinants of health and outcomes in pediatric nonaccidental trauma.

Objectives: Nonaccidental trauma (NAT) is a leading cause of pediatric mortality and disability. We examined our institution's experience with NAT to determine if socioeconomic status is correlated with patient outcomes.

Methods: NAT cases were reviewed retrospectively.

Clinical and Imaging Correlates of Pediatric Mucosal Appendicitis.

Background: Mucosal appendicitis is a controversial entity that is histologically distinct from transmural appendicitis. There is mixed opinion regarding mucosal inflammation as a spectrum of appendicitis versus a negative appendectomy. The ability to distinguish these diagnoses preoperatively is of importance to prevent unnecessary surgery.

Diagnostic Utilization and Accuracy of Pediatric Appendicitis Imaging at Adult and Pediatric Centers.

Background: Diagnostic imaging in pediatric appendicitis may decrease rates of negative appendectomy and identify alternate pathologies. We compared imaging practices for children transferred from nonpediatric facilities versus directly admitted to our tertiary children's hospital for laparoscopic appendectomy, and assessed the diagnostic accuracy in each population based on final pathologic diagnosis.

Materials And Methods: After institutional review board approval, all cases of laparoscopic appendectomy at our children's hospital during 2015 were reviewed.

Wounds Inhibit Tumor Growth In Vivo.

Objective: The aim of this study was to determine the interaction of full thickness excisional wounds and tumors in vivo.

Summary Of Background Data: Tumors have been described as wounds that do not heal due to similarities in stromal composition. On the basis of observations of slowed tumor growth after ulceration, we hypothesized that full thickness excisional wounds would inhibit tumor progression in vivo.

Wound healing and fibrosis: current stem cell therapies.

Scarring is a result of the wound healing response and causes tissue dysfunction after injury. This process is readily evident in the skin, but also occurs internally across organ systems in the form of fibrosis. Stem cells are crucial to the innate tissue healing response and, as such, present a possible modality to therapeutically promote regenerative healing while minimizing scaring.

Doxycycline Reduces Scar Thickness and Improves Collagen Architecture.

Objective: To investigate the effects of local doxycycline administration on skin scarring.

Background: Skin scarring represents a major source of morbidity for surgical patients. Doxycycline, a tetracycline antibiotic with off-target effects on the extracellular matrix, has demonstrated antifibrotic effects in multiple organs.

Mechanoresponsive stem cells acquire neural crest fate in jaw regeneration.

During both embryonic development and adult tissue regeneration, changes in chromatin structure driven by master transcription factors lead to stimulus-responsive transcriptional programs. A thorough understanding of how stem cells in the skeleton interpret mechanical stimuli and enact regeneration would shed light on how forces are transduced to the nucleus in regenerative processes. Here we develop a genetically dissectible mouse model of mandibular distraction osteogenesis-which is a process that is used in humans to correct an undersized lower jaw that involves surgically separating the jaw bone, which elicits new bone growth in the gap.

Author Correction: Genetic dissection of clonal lineage relationships with hydroxytamoxifen liposomes.

In the original version of this Article, the authors inadvertently omitted Elizabeth A. Brett, who contributed to the generation of the histology figures, from the author list.This has now been corrected in both the PDF and HTML versions of the Article.

Genetic dissection of clonal lineage relationships with hydroxytamoxifen liposomes.

Targeted genetic dissection of tissues to identify precise cell populations has vast biological and therapeutic applications. Here we develop an approach, through the packaging and delivery of 4-hydroxytamoxifen liposomes (LiTMX), that enables localized induction of CreER recombinase in mice. Our method permits precise, in vivo, tissue-specific clonal analysis with both spatial and temporal control.

Correlation of payor status and pediatric transfer for acute appendicitis.

Background: Tertiary referral centers provide specialty and critical care for patients presenting to hospitals that lack these resources. There is a notion among tertiary centers that outside hospitals are more likely to transfer uninsured or underinsured patients. We examined funding status of patients transferred to our tertiary pediatric hospital for surgical management of appendicitis, hypothesizing that transferred patients were more likely to have unfavorable coverage.

Renal artery aneurysm associated with Leber hereditary optic neuropathy.

Leber hereditary optic neuropathy is an inherited, rare, mitochondrial metabolic disease that leads to progressive vision loss due to the accumulation of reactive oxygen species. The disorder has been associated with microangiopathy and macroangiopathy. We present a novel case of saccular left renal artery aneurysm in a 27-year-old man with known Leber hereditary optic neuropathy.

Peritoneal Dialysis Is Feasible as a Bridge to Combined Liver-Kidney Transplant.

Patients with combined liver and kidney failure may remain on dialysis for years while awaiting simultaneous liver-kidney transplantation (SLKT). The role of peritoneal dialysis (PD) in patients with advanced liver and kidney failure awaiting SLKT remains to be defined. We present our single-institution experience with PD in cirrhotics, 3 of whom went on to receive successful SLKT.

Angiotensin-converting enzyme in cerebrospinal fluid and risk of brain atrophy.

Background: Higher angiotensin-converting enzyme (ACE) activity might increase the risk of Alzheimer's disease by increasing blood pressure, and subsequent development of cerebral small vessel disease (CSVD). Yet, it may also decrease this risk, as it functions to degrade amyloid-β, thereby reducing brain atrophy.

Objective: To examine the cross-sectional associations of serum and cerebrospinal fluid (CSF) ACE protein levels and activity with brain atrophy and CSVD in a memory clinic cohort.

The association of angiotensin-converting enzyme with biomarkers for Alzheimer's disease.

Introduction: Lower angiotensin-converting enzyme (ACE) activity could increase the risk of Alzheimer's disease (AD) as ACE functions to degrade amyloid-β (Aβ). Therefore, we investigated whether ACE protein and activity levels in cerebrospinal fluid (CSF) and serum were associated with CSF Aβ, total tau (tau) and tau phosphorylated at threonine 181 (ptau).

Methods: We included 118 subjects from our memory clinic-based Amsterdam Dementia Cohort (mean age 66 ± 8 years) with subjective memory complaints (n = 40) or AD (n = 78), who did not use antihypertensive drugs.