Is the LICOX® PtO2 system reliable for monitoring of free flaps? Comparison between two cohorts of patients.

BACKGROUND: Licox® PtO2 is a minimally invasive monitoring system for continuous measurement of tissue oxygen tension in all types of free tissue transfers. Our study compares two consecutive series of patients undergoing microsurgical reconstruction monitored with standard clinical bedside surveillance and with the Licox® PtO2 system regarding flap loss and flap salvage, the sensitivity, specificity, and cost-effectiveness. METHODS: We performed a longitudinal observational prospective study of all patients undergoing microsurgical reconstructions between 2016 and 2017. Group 1 included 43 patients that underwent standard clinical bedside postoperative flap monitoring whereas group 2 included 44 consecutive patients also monitored with Licox® PtO2 system. Flap complications such as return to theater for vascular compromise, partial and total flap loss and flap salvage rate were analyzed. RESULTS: We recorded no significant difference between the two groups regarding the rate of vascular complications (P = .31), return to the theater (P = .31), flap salvage (P = .9), partial and total flap loss (P = .36 and P = .49, respectively). When analyzing the Licox® PtO2 system monitoring group, we documented six false-positive results (13.6%) and 0 false negatives with an accuracy of 0.86, a sensibility of 1.00, and a specificity of 0.85. CONCLUSIONS: This is the first study that provides statistical data about the comparison of postoperative free flap monitoring by standard clinical bedside method and Licox® PtO2 system. For the monitoring of buried flaps, the Licox® PtO2 monitoring can be used only as a supplement to other systems. Its use, compared to near-infrared spectroscopy or clinical bedside monitoring, was not found cost-efficient.

Triple-Cut Computer-Aided Design-Computer-Aided Modeling: More Oncologic Safety Added to Precise Mandible Modeling.

PURPOSE: Computer-aided design-computer-aided modeling (CAD-CAM) has become standard in mandibular reconstruction because it offers better outcomes. Occasionally, the reconstructive plans need to be changed intraoperatively and the custom-made prefabricated devices may become inadequate. We present an efficient adjunct to the standard CAD-CAM technique that resolves this problem. MATERIALS AND METHODS: Customized surgical devices with our "triple-cut" concept were used in 5 patients for mandibular reconstruction with free fibula flap (4 after mandibular resection for squamous cell carcinoma and 1 after mandibular osteoradionecrosis). In all patients the mandibular and fibular cutting guides were provided with 3 different cutting levels per side. RESULTS: Three different cutting levels on the mandible permitted an accurate resection based on the intraoperative needs. The corresponding 3 "cutting levels" on the fibula created perfectly matching segments of vascularized bone. Good contact of bony segments was obtained in all patients. CONCLUSIONS: The prefabricated triple-cut cutting guides make changing the dimensions of bony resection, while still using the prefabricated CAD-CAM reconstructive plate, possible.

How we fix free flaps to the bone in oral and oropharyngeal reconstructions.

PURPOSE: The use of suture anchors has been described in orthopedic, hand, oculoplastic, temporomandibular joint and in aesthetic surgery, but no study reports the use of the Mitek® anchors (Depuy Mitek Surgical Products, Inc. Raynham, Massachusetts) for fixing the free flaps used in oncologic oral and oropharyngeal reconstruction. MATERIALS AND METHODS: In this prospective non-randomized study, 9 patients underwent surgical resection of oral or oropharyngeal cancer followed by a free flap reconstruction; mini anchors were used to fix the flap directly to the bone. We collected data regarding the patients, the tumor stage, the surgical procedure, the radiotherapy and the number of anchors used. RESULTS: The average follow-up was 28months (range 24-38).We observed no complications with trans-oral, sub-mandibular and trans-mandibular approach in both oral and oropharyngeal reconstructions. All anchors became osteo-integrated and no complications occurred after radiotherapy. CONCLUSIONS: In our opinion this device favors free flap adhesion to the bone. We registered no postoperative complications related to the use of the device which looks suitable for use in irradiated tissues. The radiotherapy did not cause any long-term complications related to the use of Mitek® mini bone anchors.

Secondary Microsurgical Reconstruction of the Cervical Esophagus: Safer Flaps and Practical Tips in a Challenging Situation.

Background: Cervical esophageal reconstruction is vital to improve the quality of life in cancer surgery patients. Microsurgery is crucial in providing vascularized tissue for defect repair, particularly in secondary cases with a higher risk of failure due to larger defects and damage from previous surgery and radiotherapy. The purpose of this study was to describe the clinical characteristics of a series of patients who underwent secondary repair of esophageal defects and provide practical information for the management and treatment of such cases based on the authors' experience and the literature review. Methods: We retrospectively reviewed the electronic medical records of the Plastic Surgery Clinic at the University of Trieste to identify cases of patients who underwent secondary esophageal microsurgical reconstructions following oncological surgery. Patient demographics, the etiology of esophageal defects, previous surgical history, and preoperative assessments were collected from medical records. Surgical techniques utilized for reconstruction, such as pedicled flaps or free tissue transfers, were documented along with intraoperative information. Postoperative outcomes, including complications, graft viability, and functional outcomes, were evaluated during follow-up. Results: We treated 13 cases of secondary esophageal reconstructions between 2011 and 2022. Most commonly, Antero-Lateral Thigh (ALT) flaps were used in 10 cases, while 2 cases employed a radial forearm flap (RFF), and 1 case employed a chimeric parascapular flap. No flap failures occurred during a median 50-month follow-up. One ALT flap patient experienced postop stricture but maintained swallowing ability. A single tracheoesophageal fistula occurred in an RFF patient with a history of radiotherapy and complete lymph node dissection. Conclusions: Cervical esophageal reconstruction significantly impacts patients' quality of life by restoring oral feeding and phonation. When local flaps fall short, microsurgical reconstruction with intestinal flaps is valuable but is burdened by limitations. For challenging secondary cases, ALT or RFF flaps emerge as safer options due to their robust pedicles, yielding low complication rates and positive functional outcomes.

19F/18F exchange synthesis for a novel [18F]S1P3-radiopharmaceutical.

(19)F/(18)F isotope exchange is a useful method to label drug molecules containing (19)F-fluorine with (18)F without modifying the drug molecule itself. Sphingosine-1-phosphate (S1P) is an important cellular mediator that functions by signaling through cell surface receptors. S1P is involved in several cell responses and may be related to many central nervous system disorders, including neural malfunction in Alzheimer's disease. In this study, [(18)F]1-benzyl-N-(3,4-difluorobenzyl)-2-isopropyl-6-(2-methoxyethoxy)-1H-indole-3-carboxamide, a novel (18)F-labeled positron emission tomography tracer for the S1P3 receptor, was successfully synthesized using the (19)F/(18)F isotope exchange reaction. Parameters of the reaction kinetics were studied, and correlations between the initial (18)F-activity, the amount of precursor, radiochemical yield and specific activity (SA) were determined. Contrary to expectations, high initial (18)F-activity decreased the radiochemical yield, and only a minor increase of SA occurred. This is most probably due to the complexity of the molecule and the subsequent susceptibility to radiolytic bond disruption. On the basis of the present results, a convenient condition for the (19)F/(18)F exchange reaction is the use of 2 µmol precursor with 20 GBq of (18)F-activity. This afforded a radiochemical yield of ~10% with an SA of 0.3 GBq/µmol. Results from this study are of interest for new tracer development where high initial (18)F-activity and (19)F/(18)F isotope exchange is used.

Treatment of a double-giant Rhinophyma with electrocautery and Versajet hydrosurgery system.

Rhinophyma is a disfiguring condition etiologically related to rosacea and due to hypertrophy of the sebaceous glands of the nose. It leads to a progressive thickening of the skin up to the development, in some cases, of severe deformities that result in significant functional deficits and serious cosmetic damage. We report a case of giant rhinophyma consisting of 2 large masses that interfered with feeding and respiration of the patient, and we describe the surgical treatment by resection with electrosurgery and razor-thin saline jet (Versajet Hydrosurgery System). This combined approach is simple and effective for the treatment of severe cases of rhinophyma.

Elastofibroma dorsi. Our experience with 11 lesions.

Elastofibroma is a rare benign lesion that typically arises on the posterior chest wall beneath the scapula. The etiopathogenesis is still unclear and the knowledge about its diagnosis and management mainly comes from small case series. We collected all the data related to 11 Elastofibroma Dorsi treated at our institution between January 2003 and July 2014. The definitive diagnosis was made by histological examination of the mass. We analyzed the characteristic of the patients, (i.e. age, sex, dominant hand, and occupation), the presenting symptoms and signs, the preoperative investigations, surgical management and complications comparing our findings with the current medical literature on the subject. We found that preoperative investigations are of limited value and when clinical presentation is typical the diagnosis could be made presumptively. Surgery should be performed under general anaesthesia since local anaesthetic infiltration and sedation are often inadequate to reduce intraoperative discomfort.

A phenotypic screening assay for modulators of huntingtin-induced transcriptional dysregulation.

Huntington's Disease is a rare neurodegenerative disease caused by an abnormal expansion of CAG repeats encoding polyglutamine in the first exon of the huntingtin gene. N-terminal fragments containing polyglutamine (polyQ) sequences aggregate and can bind to cellular proteins, resulting in several pathophysiological consequences for affected neurons such as changes in gene transcription. One transcriptional pathway that has been implicated in HD pathogenesis is the CREB binding protein (CBP)/cAMP responsive element binding (CREB) pathway. We developed a phenotypic assay to screen for compounds that can reverse the transcriptional dysregulation of the pathway caused by induced mutated huntingtin protein (µHtt). 293/T-REx cells were stably co-transfected with an inducible full-length mutated huntingtin gene containing 138 glutamine repeats and with a reporter gene under control of the cAMP responsive element (CRE). One clone, which showed reversible inhibition of µHtt-induced reporter activity upon treatment with the neuroprotective Rho kinase inhibitor Y27632, was used for the development of a high-throughput phenotypic assay suitable for a primary screening campaign, which was performed on a library of 24,000 compounds. Several hit compounds were identified and validated further in a cell viability adenosine triphosphate assay. The assay has the potential for finding new drug candidates for the treatment of HD.

Fused 3-Hydroxy-3-trifluoromethylpyrazoles Inhibit Mutant Huntingtin Toxicity.

Here, we describe the selection and optimization of a chemical series active in both a full-length and a fragment-based Huntington's disease (HD) assay. Twenty-four thousand small molecules were screened in a phenotypic HD assay, identifying a series of compounds bearing a 3-hydroxy-3-trifluoromethylpyrazole moiety as able to revert the toxicity induced by full-length mutant Htt by up to 50%. A chemical exploration around the series led to the identification of compound 4f, which demonstrated to be active in a Htt171-82Q rat primary striatal neuron assay and a PC12-Exon-1 based assay. This compound was selected for testing in R6/2 mice, in which it was well-tolerated and showed a positive effect on body weight and a positive trend in preventing ventricular volume enlargment. These studies provide strong rationale for further testing the potential benefits of 3-hydroxy-3-trifluoromethylpyrazoles in treating HD.

Search for the pharmacophore in prazosin for Transport-P.

Partial structures of prazosin have been synthesised and tested for inhibition of Transport-P in order to identify the structural features of prazosin, which appear to be involved in binding to the putative transporter. It is shown that the pyrimidinyl 4-amino group is critically important for binding but that the 6,7-dimethoxy and 2-furoyl groups are not essential.

Identification of Nocardia restricta in biodegraded sandstone monuments by PCR and nested-PCR DNA amplification.

Abstract We report the presence of Actinomycetes in degraded sandstone monuments, and on examination of 173 samples we identified Nocardia restricta as particularly prevalent. In our procedure, the extracted bacterial DNA was the template in polymerase chain reaction (PCR) experiments in order to amplify specific regions of the 16S rDNA. The fidelity of amplified fragment was confirmed by nested-PCR or restriction enzyme specific cutting. To confirm the specificity of the assay, the amplified fragments were cloned in a convenient plasmid vector, the sequence analysed and compared with the expected DNA genomic portion.