A hybrid nanoparticle-protein hydrogel system for prolonged local anesthesia.

Local anesthetics are effective in relieving pain, but their duration of action is short. Therefore, the development of injectable sustained release systems to prolong the effect of local anesthetics has been of interest. In such systems delivering conventional local anesthetics, it has been challenging to achieve long durations of effect, particularly without incurring tissue toxicity. To overcome these challenges, we created a platform comprising a protein hydrogel incorporating hydrophobic local anesthetic (bupivacaine) nanoparticles. The nanoparticles were prepared by anti-solvent precipitation stabilized with bovine serum albumin (BSA), followed by crosslinking with glutaraldehyde (GA). The resulting BSA hydrogels prolonged release of bupivacaine in vitro. When bupivacaine nanoparticles within crosslinked BSA were injected at the sciatic nerve in rats, a duration of nerve block of 39.9 h was obtained, compared to 5.5 h for the commercial bupivacaine liposome suspension EXPAREL®. Tissue reaction was benign. We further demonstrated that this system could control the release of the amphiphilic drug diphenhydramine and the hydrophobic paclitaxel.

Robotic-assisted laparoscopic Malone appendicostomy: a 6-year perspective.

PURPOSE: A robotic-assisted laparoscopic approach to appendicostomy offers the benefits of a minimally invasive approach to patients who would typically necessitate an open procedure, those with a larger body habitus, and those requiring combined complex colorectal and urologic reconstructive procedures. We present our experience performing robotic-assisted appendicostomies with a focus on patient selection, perioperative factors, and functional outcomes. METHODS: A retrospective review of patients who underwent a robotic-assisted appendicostomy/neoappendicostomy at our institution was performed. RESULTS: Twelve patients underwent robotic-assisted appendicostomy (n = 8) and neoappendicostomy (n = 4) at a range of 8.8-25.8 years. Five patients had a weight percentile > 50% for their age. Seven patients underwent combined procedures. Median operative time for appendicostomy/neoappendicostomy only was 185.0 min. Complications included surgical site infection (n = 3), stricture requiring minor operative revision (n = 2), conversion to an open procedure due to inadequate appendiceal length (prior to developing our technique for robotic neoappendicostomies; n = 1), and granuloma (n = 1). At a median follow-up of 10.8 months (range 1.7-74.3 months), 91.7% of patients were consistently clean with antegrade enemas. DISCUSSION: Robotic-assisted laparoscopic appendicostomy and neoappendicostomy with cecal flap is a safe and effective operative approach. A robotic approach can potentially overcome the technical difficulties encountered in obese patients and can aid in patients requiring both a Malone and a Mitrofanoff in a single, combined minimally invasive procedure.

Late Diagnosis of Hirschsprung Disease: Clinical Presentation and Long-Term Functional Outcomes.

PURPOSE: Hirschsprung Disease (HD) is typically diagnosed in the neonatal period. A small subset of patients have a prolonged course of abdominal distention and constipation prior to diagnosis. Late HD is defined as having been diagnosed at greater than or equal to one year of age. The literature is limited and offers conflicting data on the implications of a late diagnosis. We aim to investigate the presentation, operative approach, and functional outcomes of a large cohort of patients with a late HD diagnosis. METHODS: All patients with a late diagnosis of HD (after 1 year of age) at our institution between 1997 and 2021 were included. RESULTS: Twenty-eight patients were diagnosed with HD at a median age of 3.4 years. Chronic constipation, failure to thrive, and enterocolitis occurred in 100 %, 31 %, and 14 %, respectively. All patients underwent contrast enema and biopsies during their workup, identifying primarily rectosigmoid disease (n = 27) and total colonic aganglionosis (n = 1). Surgical intervention was performed in 27 patients, with 4 patients (15 %) needing a stoma (3 with plan for staged pull-through, 1 long-term stoma) and 23 patients (85 %) undergoing a single-stage pull-through. Postoperative complications included Hirschsprung-associated enterocolitis (n = 5), ostomy prolapse and revision (n = 2), abdominal distention requiring ileostomy creation (n = 2), redo pull-through (n = 2), retroperitoneal hematoma (n = 1), and cecostomy tube placement (n = 1). At a median follow-up of 5.4 years, 83 % of eligible patients achieved fecal continence with 43 % needing laxatives for persistent constipation. CONCLUSION: Recognizing a late presentation of HD requires a high index of suspicion. Patients with a late diagnosis did not experience an increased rate of permanent stoma, complications, or redo surgery compared to rates reported for the larger HD population. Similar long-term functional outcomes were achieved compared to the larger HD population. LEVEL OF EVIDENCE: IV.

Ablation of Venous Malformations by Photothermal Therapy with Intravenous Gold Nanoshells.

Venous malformations (VMs) consist of hugely enlarged and dysmorphic veins. These lesions cause significant disfigurement, pain, and complications such as bleeding and coagulopathy. Pharmacotherapy for the treatment of VMs has limited efficacy and potentially limiting toxicity. Current treatment for patients with VMs entails life-long pharmacotherapy or surgical procedures. Here we explored whether intravenously administered agents can be used to destroy VMs by photothermal therapy (PTT), using gold nanoshells (AuNSs) that generated heat following irradiation with near-infrared (NIR) light. In a murine model of VMs, intravenous AuNSs accumulated within the VMs. Irradiation of the VMs induced marked regression and even elimination. Nanoparticle-based photothermal therapy can provide effective therapy for VMs, which are otherwise relatively refractory to treatment.

Evidence to Underpin Vitamin A Requirements and Upper Limits in Children Aged 0 to 48 Months: A Scoping Review.

Vitamin A deficiency is a major health risk for infants and children in low- and middle-income countries. This scoping review identified, quantified, and mapped research for use in updating nutrient requirements and upper limits for vitamin A in children aged 0 to 48 months, using health-based or modelling-based approaches. Structured searches were run on Medline, EMBASE, and Cochrane Central, from inception to 19 March 2021. Titles and abstracts were assessed independently in duplicate, as were 20% of full texts. Included studies were tabulated by question, methodology and date, with the most relevant data extracted and assessed for risk of bias. We found that the most recent health-based systematic reviews and trials assessed the effects of supplementation, though some addressed the effects of staple food fortification, complementary foods, biofortified maize or cassava, and fortified drinks, on health outcomes. Recent isotopic tracer studies and modelling approaches may help quantify the effects of bio-fortification, fortification, and food-based approaches for increasing vitamin A depots. A systematic review and several trials identified adverse events associated with higher vitamin A intakes, which should be useful for setting upper limits. We have generated and provide a database of relevant research. Full systematic reviews, based on this scoping review, are needed to answer specific questions to set vitamin A requirements and upper limits.