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Placental phospholipid synthesis is critical for the expansion of the placental exchange surface area and for production of signaling molecules. Despite their importance, it is not yet established which enzymes involved in the de novo synthesis and remodeling of placental phospholipids are expressed and active in the human placenta. We identified phospholipid synthesis enzymes by immunoblotting in placental homogenates and immunofluorescence in placenta tissue sections. Primary human trophoblast (PHT) cells from term healthy placentas (n = 10) were cultured and exposed to 13C labeled fatty acids (16:0, 18:1 and 18:2 n-6, 22:6 n-3) for 2 and 24 h. Three phospholipid classes; phosphatidic acid, phosphatidylcholine, and lysophosphatidylcholine containing 13C fatty acids were quantified by Liquid Chromatography with tandem mass spectrometry (LC/MS–MS). Acyl transferase and phospholipase enzymes were detected in human placenta homogenate and primarily expressed in the syncytiotrophoblast. Three representative 13C fatty acids (16:0, 18:1 and 18:2 n-6) were incorporated rapidly into phosphatidic acid in trophoblasts, but 13C labeled docosahexaenoic acid (DHA; 22:6 n-3) incorporation was not detected. 13C DHA was incorporated into phosphatidylcholine. Lysophosphatidylcholine containing all four 13C labeled fatty acids were found in high abundance. Phospholipid synthesis and remodeling enzymes are present in the syncytiotrophoblast. 13C labeled fatty acids were rapidly incorporated into cellular phospholipids. 13C DHA was incorporated into phospholipids through the remodeling pathway rather than by de novo synthesis. These understudied pathways are highly active and critical for structure and function of the placenta. • Human placenta trophoblasts express de novo phospholipid synthesis and phospholipid remodeling enzymes. • Uniformly labeled 13C fatty acids are rapidly incorporated into cellular phospholipid lipids. • Docosahexaenoic acid is incorporated into trophoblast phospholipids through the remodeling pathway as evidenced by a lack of 13C DHA in the phosphatidic acid form. [ABSTRACT FROM AUTHOR]

Introduction: The uterus and placenta transport water during pregnancy recognition signaling, conceptus implantation, and placental development/placentation. This is likely influenced by aquaporins (AQPs) in the reproductive tract. This study determined mRNA and cell-type specific expression of AQP 1, 5, 8, and 9 proteins in the porcine uterus and placenta.Methods: Porcine uteri and Chorioallantois were subjected to real-time PCR and immunofluorescence microscopy.Results: AQP1 mRNA was maximal by Day 25 in endometrium and remained stable thereafter. AQP1 mRNA did not change in chorioallantois. AQP1 protein localized to erythrocytes and endothelium of the endometrium and allantois, and to smooth muscle of the myometrium. AQP5 protein localized to apical and lateral surfaces of the chorionic epithelia of areolae, but mRNA did not change in chorioallantois. AQP8 mRNA was high in the endometrium from Days 15 through 60 of gestation, and protein localized to multiple cell types within the endometrium and chorioallantois. AQP9 mRNA was highest in the endometrium on Days 10, 12 and 25, but did not change in the chorioallantois. AQP9 protein localized to the apical surface of endometrial luminal epithelial cells during early pregnancy, with a shift towards the basal surface later. AQP9 protein was observed in the allantoic epithelium.Discussion: Results reveal pigs can potentially use AQP1, AQP5, AQP8, and AQP9 to transport water from the endometrial bloodstream to the allantoic bloodstream or allantoic fluid. The reverse is also possible and may explain the mechanism for changing volumes of allantoic fluid and hydration of allantoic connective tissues during pregnancy. [ABSTRACT FROM AUTHOR]

Minimally invasive fetal surgery, or fetoscopy, is an alternative to open fetal surgery to repair common birth defects like myelomeningocele. Although this hysterotomy-sparing approach reduces maternal morbidity, the effects of in utero insufflation on the fetus are poorly understood. Our purpose was to determine the optimal fetal insufflation conditions. Fetal sheep at gestational age 104 to 107 days were studied under insufflation conditions in utero and ex utero. The ex utero fetuses were cannulated via their umbilical vessels into a support device, the EXTra-uterine Environment for Neonatal Development (EXTEND). EXTEND fetuses were exposed to four different insufflation conditions for four hours: untreated carbon dioxide (CO 2) (n = 5), warm humidified (whCO 2) (n = 4), whCO 2 with the umbilical cord exposed (n = 3), and whCO 2 without amniotic fluid (skin and cord exposed) (n = 3). In utero insufflation led to significant increases in fetal CO 2 and reductions in fetal pH. Ex utero insufflation with whCO 2 did not lead to changes in fetal blood gas measurements or cerebral perfusion parameters. Insufflation with whCO 2 with an exposed umbilical cord led to reduced umbilical blood flow. Insufflation with warm humidified CO 2 with an amniotic fluid covered umbilical cord is well tolerated by the fetus without significant changes in hemodynamics or cerebral perfusion parameters. Basic science N/A [ABSTRACT FROM AUTHOR]

In the United Kingdom (UK) the estimated prevalence of dental infection involving the supporting bone is 2%, and from 2014–2015 there were 2281 admissions in England alone due to dental abscess. We undertook an analysis of 184 dental abscesses that required surgical drainage, as there is surprisingly little in the literature on the subject. This was a retrospective study of 184 consecutive patients with dental abscesses who were admitted between January 2016 and September 2019. On admission, all patients had orthopantomograms (OPG) and baseline blood tests. Surgical drainage was performed under a general or local anaesthetic and a pus swab sent for culture and sensitivity. The submandibular space was the most commonly involved site and paediatric patients most often presented with buccal space abscesses. A lower molar tooth was the cause in 132 patients. White blood cells (WBC) and C-reactive protein (CRP) were both raised in 63.6% (n = 117), but were normal in 4.9% (n = 9). The remaining patients had either raised WBC (2.7%) or CRP (28.8%). Streptococcus milleri was the most common organism isolated in 66.6% (n = 42). There was no association between CRP or WBC values and duration of hospital stay. Paediatric patients had a shorter duration of admission (1.96 days vs 2.81 days) and significantly lower CRP values (120.9 vs 45.7; p = 0.001). The submandibular space was the commonest site involved and mandibular molars the most frequent source of infection. An elevated CRP value appeared to be a more sensitive indicator of infection in this study population. Adult and paediatric patients present in a different manner. [ABSTRACT FROM AUTHOR]

Children with acute appendicitis have historically received intravenous antibiotics before and after appendectomy, yet recent literature supports minimizing postoperative antibiotics. In this study, we examined the impact of a standardized protocol that eliminates postoperative antibiotics for nonperforated appendicitis and discontinues antibiotics at discharge for perforated appendicitis. A retrospective review of all pediatric patients who underwent laparoscopic appendectomy for acute appendicitis between May 2013 and March 2017 was performed. Preprotocol patients (5/1/2013–3/31/2015) were compared to postprotocol patients (5/1/2015–3/31/2017), excluding those who underwent surgery during the month of protocol introduction (4/2015). Primary outcomes were postoperative antibiotic doses for nonperforated cases and antibiotics after discharge for perforated cases. Mann–Whitney and Fisher's exact tests were performed. Laparoscopic appendectomy was performed in 748 children before (PRE) and in 814 children after (POST) protocol implementation. Perforation rates were similar (POST 21.5 vs. PRE 21.8%, p = 0.90). For nonperforated appendicitis, postoperative antibiotics were reduced (median 0 [IQR 0–0] vs. 3 [0–5] doses, p < 0.001), and more patients were discharged less than 24 h after surgery (65.7 vs. 40.9%, p < 0.001). Fewer patients with perforated appendicitis underwent PICC placement (8.6 vs. 21.0%, p = 0.002), and fewer patients were prescribed antibiotics on discharge (33.7 vs. 89.0%, p < 0.001). There were no differences between groups for complication, readmission, or return to ED rates. For children with acute appendicitis, a standardized protocol can safely reduce unnecessary antibiotics and decrease length of stay. Furthermore, the judicious use of antibiotics does not increase SSI, readmission, or overall complication rates. III [ABSTRACT FROM AUTHOR]

Neurologic injury remains the most important morbidity of prematurity. Those born at the earliest gestational ages can face a lifetime of major disability. Perinatal insults result in developmental delay, cerebral palsy, and other profound permanent neurologic impairments. The EXTracorporeal Environment for Neonatal Development (EXTEND) aims to transition premature neonates through this sensitive period, but it's impact on neurologic development requires analysis. Fetal sheep were maintained in a fluid-filled environment for up to 28 days. Physiologic parameters were measured continuously; tissues were subsequently fixed and preserved for myelin quantification, glial cell staining, and structural assessment via magnetic resonance. Surviving animals were functionally assessed. No evidence of fetal brain ischemia or white matter tract injury associated with the EXTEND system was detected, and the degree of myelination was regionally appropriate and consistent with age matched controls. No evidence of neurologic injury or immaturity was visible on magnetic resonance; animals that transitioned from the system had no persistent neurologic deficits. No evidence of major neurologic morbidity was found in animals supported on the EXTEND system, though more work needs to be done in order to verify its safety during critical periods of neurologic development. [ABSTRACT FROM AUTHOR]

Congenital heart disease (CHD) is associated with abnormal fetal brain development, a phenomenon that may be related to decreased cerebral oxygen delivery in utero. We used an artificial womb model to test the hypothesis that decreasing fetal oxygen delivery would reproduce physiologic changes identified in fetuses with CHD. Experimental (hypoxemic) fetal lambs (mean gestational age, 111 ± 3 days; n = 4) and control animals (112 days; n = 5) were maintained in the artificial womb for a mean of 22 ± 6 days. Oxygen delivery was reduced to 15.6 ± 1.0 mL/kg/min in the hypoxemia animals versus 21.6 ± 2.0 mL/kg/min in the control animals. Blood chemistry analysis and sonographic evaluation were performed daily. An additional control group (n = 7) was maintained in utero and harvested for analysis at gestational age 134 ± 4 days. Physiologic variables were monitored continuously, and no statistical differences between the groups were identified. Fetal oxygen delivery and arterial partial pressure of oxygen were remarkably lower in the experimental group longitudinally. Increased umbilical artery and decreased middle cerebral artery resistance resulted in a lower cerebral to umbilical resistance ratio, similar to the brain sparing effect observed in human fetuses with CHD. Experimental brains were smaller than control brains in relation to the calvarium on magnetic resonance. Sustained hypoxemia in fetal sheep leads to altered cerebrovascular resistances and loss of brain mass, similar to human fetuses with CHD. This unique model provides opportunities to investigate the pathologic process underlying CHD-associated brain dysmaturity and to evaluate potential fetal neuroprotective therapies. [ABSTRACT FROM AUTHOR]

Neuroimmune cells, particularly microglia and astrocytes, play a critical role in neurodevelopment. Neurocognitive delays are common in children with congenital heart disease, but their etiology is poorly understood. Our objective was to determine whether prenatal hypoxemia, at levels common in congenital heart disease, induced neuroimmune activation to better understand the origins of neurobehavioral disorders in congenital heart disease. Eight fetal sheep at gestational age 109 ± 3 days (term ∼145 days) were cannulated onto a pumpless extracorporeal oxygenator via the umbilical vessels and supported in a fluid environment for 22 ± 2 days under normoxic (n = 4) or hypoxic (n = 4) conditions. Control fetuses (n = 7) were harvested at gestational age 133 ± 4 days. At necropsy, brains were stained with ionized calcium-binding adaptor molecule 1 and glial fibrillary acidic protein antibodies to quantify microglia and astrocytes, respectively, in gray and white matter in frontotemporal and cerebellar sections. Microglia were classified into 4 morphologic types based on cell shape. Data were analyzed with 1-way analysis of variance or Fisher exact test, as appropriate. Oxygen delivery was significantly reduced in hypoxic fetuses (15.6 ± 1.8 mL/kg/min vs 24.3 ± 2.3 mL/kg/min; P <.01). Rates of apoptosis were similar in hypoxic, normoxic, and intrauterine control animals in all examined areas. There were also no differences between groups in area occupied by glial fibrillary acidic protein-labeled astrocytes or ionized calcium-binding adaptor molecule 1-labeled microglia in all examined areas. However, round microglia were significantly increased in hypoxic animals compared with normoxic animals (33% vs 6%; P <.01) and control animals (33% vs 11%; P <.01). Prenatal hypoxemia altered microglial morphology without significant gliosis. Additional studies characterizing these mechanisms may provide insight into the origins of neurobehavioral disabilities in children with congenital heart disease. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that chronic fetal hypoxia, at a severity present in many types of congenital heart disease, would lead to abnormal neurodevelopment. Eight mid-gestation fetal sheep were cannulated onto a pumpless extracorporeal oxygenator via the umbilical vessels and supported in a fluid-filled environment for 22 ± 2 days under normoxic or hypoxic conditions. Total parenteral nutrition was provided. Control fetuses (n = 7) were harvested at gestational age 133 ± 4 days. At necropsy, brains were fixed for histopathology. Neurons were quantified in white matter tracts, and the thickness of the external granular layer of the cerebellum was measured to assess neuronal migration. Capillary density and myelination were quantified in white matter. Data were analyzed with unpaired Student t tests or 1-way analysis of variance, as appropriate. Oxygen delivery was reduced in hypoxic fetuses (15.6 ± 1.8 mL/kg/min vs 24.3 ± 2.3 mL/kg/min, P <.01), but umbilical blood flow and caloric delivery were not different between the 2 groups. Compared with normoxic and control animals, hypoxic fetuses had reduced neuronal density and increased external granular layer thickness. Compared with normoxic and control animals, hypoxic fetuses had increased capillary density in white matter. Cortical myelin integrity score was lower in the hypoxic group compared with normoxic and control animals. There was a significant negative correlation between myelin integrity and capillary density. Chronic fetal hypoxia leads to white matter hyper-vascularity, decreased neuronal density, and impaired myelination, similar to the neuropathologic findings observed in children with congenital heart disease. These findings support the hypothesis that fetal hypoxia, even in the setting of normal caloric delivery, impairs neurodevelopment. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to characterize the current state of surgical ergonomics education in the United States. Background: The burden of work-related musculoskeletal disorders (MSDs) in surgeons is high and no overarching strategy for redress exists. Twelve distinct specialties describe an unmet need for surgical ergonomics education (SEE). This study aimed to define the current state of SEE in U.S. surgical training programs. Methods: We performed a descriptive analysis of a 20-item questionnaire of ACGME-certified program directors from 14 surgical and interventional medical specialties. Formal SEE was defined as any organized education module that reviewed the occupation-specific burden of common work-related MSDs and described a framework for prevention via occupation-specific applied ergonomics. Program directors were queried regarding SEE provision, characteristics, and perceived trainee attitude toward the education. Results: Questionnaires were received from 130 of 441 (29.5%) program directors. Two (1.5%) provided formal SEE and 33 (25.4%) provided informal SEE, which consisted of unstructured intraoperative directives and isolated lectures. Two programs previously provided SEE but discontinued the effort due to lack of an evidence-based framework and instructors. Trainees appeared to think that learning surgical ergonomics skills was a worthwhile time investment in 100% and 76.7% of current formal and informal SEE, respectively. Conclusion: SEE is rarely provided in any capacity (25.4%), let alone in a consistent or evaluable fashion (1.5%). Impediments to sustainable SEE include lack of an evidence-based framework for education and instructors. An evidence-based, reproducible, and accreditation council-compliant SEE module would be a valuable resource for the surgical and interventional medical communities. [ABSTRACT FROM AUTHOR]

Background/purpose Blunt cerebrovascular injury (BCVI) is clinically challenging because these injuries are hard to detect and can have serious neurological consequences, and optimal screening criteria have not been established for children. This study aims to determine risk factors for BCVI in pediatric patients and to evaluate screening practices in a single institutional series. Methods A retrospective review of all pediatric blunt trauma patients evaluated over a 10-year period was performed. Demographic, clinical, and radiographic data were reviewed, including the presence of adult risk factors for BCVI. Logistic regression analyses were performed with statistical significance established at p < 0.05. Results Of the 11,596 patients evaluated during the study period, 1018 (8.8%) had at least one adult risk factor for BCVI, but only 62 (6.1% of those with risk factors) underwent angiographic evaluation. Overall, 11 BCVIs were observed, resulting in an incidence of 0.095%. All 11 patients with BCVI had at least one risk factor. Multivariate logistic regression analysis identified cervical spine fracture (OR 36.88 [8.36, 169.95]), GCS score ≤ 8 (OR 16.42 [2.16, 102.33]), male gender (OR 10.52 [1.33, 363.30]), Le Fort II or III facial fracture (OR 63.71 [2.16, 1124.68]), and ISS (unit OR 1.10 [1.04, 1.17]) as independent risk factors for BCVI. Conclusion Adult screening criteria for BCVI appear appropriate for pediatric patients, but most at-risk children are not being screened. Level of evidence Level III (retrospective case-control study). [ABSTRACT FROM AUTHOR]

Proopiomelanocortin (POMC) neurons are the key anorexigenic hypothalamic neuron for integrating metabolic cues to generate the appropriate output for maintaining energy homeostasis and express the requisite channels as a perfect synaptic integrator in this role. Similar to the metabolic hormones leptin and insulin, glutamate also excites POMC neurons via group I metabotropic glutamate receptors (mGluR1 and 5, mGluR1/5) that activate Transient Receptor Potential Canonical (TRPC 5) Channels to cause depolarization. A key modulator of TRPC 5 channel activity is stromal interaction molecule 1 (STIM1), which is involved in recruitment of TRPC 5 channels from receptor-operated to store-operated calcium entry following depletion of calcium from the endoplasmic reticulum. We used a single adeno-associated viral (AAV) vector containing a recombinase-dependent Staphylococcus aureus Cas9 (SaCas) and a single guide RNA (sgRNA) to mutate Stim1 in POMCCre neurons in male mice, verified by qPCR of Stim1 mRNA expression in single POMC neurons. Whole-cell patch clamp experiments were conducted to validate the effects of Stim1 mutagenesis. Body weight and food intake were measured in male mice to assess disruptions in energy balance. Reduced Stim1 expression augmented the efficacy of the mGluR1/5 agonist 3, 5-Dihydroxyphenylglycine (DHPG) to depolarize POMC neurons via a Gα q -coupled signaling pathway, which is an essential part of excitatory glutamatergic input in regulating energy homeostasis. The TRPC 5 channel blockers HC070 and Pico145 antagonized the excitatory effects of DHPG. As proof of principle, mutagenesis of Stim1 in POMC neurons reduced food intake, attenuated weight gain, reduced body fat and fat pad mass in mice fed a high fat diet. Using CRISPR technology we have uncovered a critical role of STIM1 in modulating glutamatergic activation of TRPC 5 channels in POMC neurons, which ultimately is important for maintaining energy balance. • CRISPR/SaCas9 vector selectively reduces Stim1 expression in adult POMC neurons. • Reduced Stim1 augments the efficacy of mGluR1/5 agonist DHPG to excite POMC neurons. • Selective TRPC 5 channel blockers antagonize the excitatory effects of DHPG. • Mutagenesis of Stim1 reduces food intake, weight gain in mice fed a high fat diet. [ABSTRACT FROM AUTHOR]

Changes to guidance about the two-week wait referrals for suspected cancer of the head and neck have created a new recommendation for a general medical practitioner to refer any patients to a dentist under certain criteria. The potential effect of this was assessed based on 91 referrals to an oral and maxillofacial unit. A total of 33 met the criteria for initial referral to a dentist; of these, one was later diagnosed with cancer. We outline the potential deleterious effects the new guidance might have on the rapid diagnosis of oral lesions. [ABSTRACT FROM AUTHOR]

Pseudoaneurysm at the anastomosis of the free flap following ablative head and neck surgery is uncommon. We present a case of external carotid artery pseudoaneurysm in a patient who had previously undergone a subtotal glossectomy, neck dissection, and radial forearm free flap reconstruction. The traditional treatment for pseudoaneurysm has been open surgical repair. Our patient underwent successful treatment with an endovascular embolization utilizing thrombin injection of the aneurysmal sac. This case highlights the role of interventional radiology in the management of this rare but important complication of microvascular reconstructive surgery. [ABSTRACT FROM AUTHOR]

Abstract: Insertion of a percutaneous endoscopic gastrostomy (PEG) was attempted on 225 occasions, mainly for oral malignancy. Seventy-five percent (169/225) were inserted at the time of definitive surgery. There were significant incidental findings during 5% (11/225). The rate of successful insertion was 97% (219/225). The incidence of minor complications was 12% (26/225) and major complications 3% (7/225). There was no procedure-related mortality. The 30-day mortality rate, including those with terminal malignant disease, was 6% (14/225). An increased risk of death was associated with age of 65 years and over (P =0.004). The median PEG duration was 337 (SE 31) days. Duration was significantly longer for stage T3–4 tumours (P =0.028), N1 or greater neck disease (P =0.034), following surgery with radiotherapy when compared to surgery alone (P <0.001), particularly glossectomy (P =0.038) and maxillectomy procedures (P =0.003), after two separate surgical procedures and radiotherapy (P =0.046) and following a composite bone resection (P =0.031), or radiotherapy alone when compared to surgery alone (P =0.003). There was no relationship to the type of flap used for reconstruction. Four patients have a long-term PEG. Only two patients did not use the PEG. The early insertion of a PEG in all patients undergoing free or pedicled flap reconstruction appears to be appropriate. The PEG procedure may be safely performed by an appropriately trained maxillofacial surgeon. [Copyright &y& Elsevier]

Abstract: This is a prospective study of 121 consecutive radial septocutaneous flaps harvested by one surgeon. There were 117 successful flaps (97%). The incidence of early return to theatre for potential problems with the flap or the neck wound was 12/121 (10%) and the flap salvage rate was 3/7 (43%). The incidence of three early wound healing complications at the suprafascial donor site were: loss of the skin graft (4%), tendon exposure (3%) and delayed healing (4%). A full-thickness skin graft, usually from the inner upper arm, was used to repair three-quarters of donor site defects. The median time to healing was significantly longer for partial thickness grafts (14 days compared with 10 days, p <0.001). The degree of contraction of the skin graft used to repair the radial defect was significantly less for full thickness than partial thickness grafts (median −21% compared with −33%, p =0.01). There was more relative contraction with larger grafts (p <0.001) and in older patients (p =0.01). The septocutaneous radial flap is reliable. The early morbidity at the suprafascial donor site is relatively low in comparison to that reported at the subfascial donor site. [Copyright &y& Elsevier]

Arcuate nucleus neuropeptide Y/agouti-related peptide (NPY/AgRP) neurons drive ingestive behavior. The M-current, a subthreshold non-inactivating potassium current, plays a critical role in regulating NPY/AgRP neuronal excitability. Fasting decreases while 17β-estradiol increases the M-current by regulating the mRNA expression of Kcnq2 , 3 , and 5 (Kv7.2, 3, and 5) channel subunits. Incorporating KCNQ3 into heteromeric channels has been considered essential to generate a robust M-current. Therefore, we investigated the behavioral and physiological effects of selective Kcnq3 deletion from NPY/AgRP neurons. We used a single adeno-associated viral vector containing a recombinase-dependent Staphylococcus aureus Cas9 with a single-guide RNA to selectively delete Kcnq3 in NPY/AgRP neurons. Single-cell quantitative measurements of mRNA expression and whole-cell patch clamp experiments were conducted to validate the selective knockdown. Body weight, food intake, and locomotor activity were measured in male mice to assess disruptions in energy balance. The virus reduced the expression of Kcnq3 mRNA without affecting Kcnq2 or Kcnq5. The M-current was attenuated, causing NPY/AgRP neurons to be more depolarized, exhibit a higher input resistance, and require less depolarizing current to fire action potentials, indicative of increased excitability. Although the resulting decrease in the M-current did not overtly alter ingestive behavior, it significantly reduced the locomotor activity as measured by open-field testing. Control mice on a high-fat diet exhibited an enhanced M-current and increased Kcnq2 and Kcnq3 expression, but the M-current remained significantly attenuated in KCNQ3 knockdown animals. The M-current plays a critical role in modulating the intrinsic excitability of NPY/AgRP neurons that is essential for maintaining energy homeostasis. • SaCas9 CRISPR vector selectively reduces Kcnq3 expression in NPY/AgRP neurons. • Knockdown of Kcnq3 significantly attenuates the M current. • While ingestive behavior appears normal, locomotion is significantly reduced. • A high-fat diet in conjunction with Kcnq3 knockdown promotes weight gain. • A high-fat diet increases Kcnq3 mRNA and the M current in control NPY/AgRP neurons. [ABSTRACT FROM AUTHOR]