Incidence of Surgical Site Infections after Transcervical Thyroidectomy in Patients Given Antibiotics versus those without Antibiotics in a Government Hospital in the Philippines.

Background and Objectives: Surgical site infection (SSI) makes up the largest single group of postoperative infective complications. For surgeries classified as clean surgeries of the head and neck, such as a thyroidectomy, the routine administration of antimicrobial prophylaxis is not recommended. Despite this, extended usage of antibiotics is common in developing countries. This study evaluated the need for antibiotics in elective transcervical thyroidectomy for the prevention of SSI in a tertiary government hospital in a developing country. Methods: This is a retrospective cohort study that included patients who have undergone elective transcervical thyroidectomy at the Department of Otolaryngology - Head and Neck Surgery (ORL-HNS) of the University of the Philippines - Philippine General (UP-PGH) Hospital from August 1, 2020 to June 30, 2022. Data collection was conducted through review of both in-patient and out-patient records. Results: The data of 58 patients were analyzed. The mean (±SD) age was 42.5±14.5 years, with approximately 2:27 male to female ratio. Of the 58 patients, 26 were given postoperative antibiotics while 32 did not receive postoperative antibiotics. None of the 58 were noted to have SSI on the 3rd postoperative day. Only 54 patients completed the 7-day follow-up of the study and their data were further analyzed. One patient had SSI. There was no significant difference between the presence and absence of postoperative antibiotics in relation to SSI (p-value>0.05). Conclusion: This study shows that in patients undergoing transcervical thyroidectomies, there is no significant difference in the occurrence of SSI among patients who received and did not receive postoperative antibiotics. Therefore, there is no need to administer postoperative antibiotics, as long as a sterile surgical technique is ensured.

Incidence of surgical site infections after transcervical thyroidectomy in patients given antibiotics versus those without antibiotics in a government hospital in the Philippines

Background and Objectives@#Surgical site infection (SSI) makes up the largest single group of postoperative infective complications. For surgeries classified as clean surgeries of the head and neck, such as a thyroidectomy, the routine administration of antimicrobial prophylaxis is not recommended. Despite this, extended usage of antibiotics is common in developing countries. This study evaluated the need for antibiotics in elective transcervical thyroidectomy for the prevention of SSI in a tertiary government hospital in a developing country. @*Methods@#This is a retrospective cohort study that included patients who have undergone elective transcervical thyroidectomy at the Department of Otolaryngology - Head and Neck Surgery (ORL-HNS) of the University of the Philippines - Philippine General (UP-PGH) Hospital from August 1, 2020 to June 30, 2022. Data collection was conducted through review of both in-patient and out-patient records.@*Results@#The data of 58 patients were analyzed. The mean (±SD) age was 42.5±14.5 years, with approximately 2:27 male to female ratio. Of the 58 patients, 26 were given postoperative antibiotics while 32 did not receive postoperative antibiotics. None of the 58 were noted to have SSI on the 3rd postoperative day. Only 54 patients completed the 7-day follow-up of the study and their data were further analyzed. One patient had SSI. There was no significant difference between the presence and absence of postoperative antibiotics in relation to SSI (p-value>0.05).@*Conclusion@#This study shows that in patients undergoing transcervical thyroidectomies, there is no significant difference in the occurrence of SSI among patients who received and did not receive postoperative antibiotics. Therefore, there is no need to administer postoperative antibiotics, as long as a sterile surgical technique is ensured.

Multi-analytical characterisation of blotting sands on documents from religious orders in Portugal (16th-19th centuries).

Too little is known about areia de escrever, i.e., blotting sands, the intriguing particles sprinkled on freshly written scripts to accelerate the drying time of the ink. Blotting sands constitute a valuable but underestimated historical source. This work investigated the blotting sands used on the account books of the religious houses scattered across continental Portugal and Madeira Island (16th-19th centuries). The sands were mainly composed of different minerals, predominately black sands, but in a few cases, minerals were found mixed with gums, paper cocoons or bone shavings. The combined use of SEM-EDS, µ-Raman and FT-IR techniques uncovered the materials' chemical or mineralogical composition and morphology. This approach, allied with image analysis and statistics complemented with multivariate analysis, allowed us to look for trends between the samples and hypothesise about their provenance. Heavy minerals, such as ilmenite, hematite and almandine, were identified as major components, together with other silicates (e.g. quartz). Samples were dominated by medium-sized grains with shape features indicating texturally mature sediments resulting from a medium-to-long sedimentary transport. Due to shorter geological transport distances, Madeira Island was the exception, with more angular grains. This work allowed us to uncover blotting sands, value them as historical sources, and establish a roadmap for their use in Portugal, aiming to pave the way towards a more global context in Europe.

A dysfunctional larynx dilemma: Carcinoma recurrence or radiation-induced damage?

@#A 61-year-old male diagnosed with laryngeal squamous cell carcinoma presented with hoarseness, progressive dysphagia leading to aspiration, and dyspnea one month after definitive radiation therapy. Examination revealed a diffusely swollen glottis, paralyzed vocal cords, and post-radiation fibrosis. Several glottic biopsies yielded results negative for malignancy and favored radiation-induced changes. When presented with the option of further diagnostic testing with a positron emission tomography (PET) scan or an outright laryngectomy, the patient decided on the latter. Final histopathologic diagnosis was negative for recurrence of malignancy. This case demonstrates treatment dilemmas for patients with laryngeal carcinoma with uncertain recurrence wherein radical surgical management may prove to be a viable option to achieve both diagnostic certainty and ultimate relief of symptoms.

Reacción anafilactoide a látex tras colocación de malla transvaginal para corrección de cistocele / Anaphylactoid latex reaction after transvaginal mesh placement for cystocele correction

La incidencia de alergia al látex en la población general es del 1-2%, siendo las reacciones más frecuentemente descritas de hipersensibilidad inmediata o tipo i y tardía o tipo iv, aunque también han sido descritas reacciones de hipersensibilidad no mediadas por IgE.Presentamos el caso de una mujer de 71 años con factores de riesgo cardiovascular (HTA y DLP) e intervenida previamente de colecistectomía y cistocele que ingresa de forma programada para intervención de recidiva de cistocele grado iv tras 4 años de la primera intervención.En el postoperatorio inmediato presenta fracaso renal agudo, por lo que se retira la malla a las 24h, persistiendo deterioro progresivo del estado general con dificultad respiratoria, disminución del nivel de conciencia y empeoramiento de la función renal. Tras una exploración exhaustiva se visualiza eritema en región vulvar e inguinal, por lo que se sospecha reacción anafiláctica a sonda de látex, que se recambia por una sonda de silicona, iniciándose tratamiento con metilprednisolona intravenosa y se consulta con el servicio de Alergología, que establece finalmente el diagnóstico.La paciente requirió ingreso en la unidad de cuidados intensivos durante 10 días por insuficiencia renal aguda e insuficiencia respiratoria aguda asociadas a íleo paralítico y coagulopatía.La anafilaxia es una reacción sistémica aguda que resulta en la liberación brusca de mediadores de los mastocitos y basófilos, mediada o no por IgE. Se admite que es una reacción de hipersensibilidad sistémica grave, de inicio repentino y potencialmente mortal. Clínicamente se asocia a la aparición de manifestaciones cutáneas relacionadas con alteraciones cardiovasculares, respiratorias o gastrointestinales.

Allergy to latex in the general population is 1-2%, the most frequent reactions described being immediate or type i and late or type iv hypersensitivity, although non-IgE-mediated hypersensitivity reactions have also been described.We present the case of a 71-year-old woman with cardiovascular risk factors (HTN and PLD) and previously operated on for cholecystectomy and cystocele who was admitted on a scheduled basis for intervention for grade iv cystocele recurrence, 4 years after the first intervention.In the immediate postoperative period, she presented acute renal failure, for which the mesh was removed after 24h, her general condition progressively deteriorated with respiratory distress, decreased level of consciousness, and worsening of renal function. After an exhaustive examination, erythema was visualized in the vulvar and inguinal region, hence the suspicion of an anaphylactic reaction to a latex catheter, which was replaced by a silicone catheter. Treatment was started with intravenous methylprednisolone, and the Allergology service was consulted who finally established the diagnosis.The patient required admission to the intensive care unit for 10 days due to acute renal failure and acute respiratory failure, associated with paralytic ileus and coagulopathy.Anaphylaxis is an acute systemic reaction that results in the abrupt release of mediators from mast cells and basophils, mediated or not by IgE. It is recognized to be a severe, sudden onset, and life-threatening systemic hypersensitivity reaction. Clinically, it is associated with the appearance of skin manifestations related to cardiovascular, respiratory, or gastrointestinal disorders.

Angiomiolipoma renal y complejo esclerosis tuberosa: resultados a largo plazo en seguridad y eficacia de terapia con everolimus / Renal angiomyolipoma and tuberous sclerosis complex: long-term safety and efficacy outcomes of Everolimus therapy

Introducción: El angiomiolipoma renal (AMLr) es una manifestación frecuente del complejo de esclerosis tuberosa (CET), estableciéndose, recientemente, el tratamiento con everolimus, como opción terapeútica novedosa, alternativa y no invasiva; sin embargo, existen datos limitados en la vida real y a largo plazo, por ello, el análisis de nuestra experiencia, en materia de seguridad y eficacia, aporta un valor añadido.Material y métodosSe realiza un análisis descriptivo de nuestra experiencia en pacientes con AMLr bilaterales gigantes, en el contexto de CET, tratados con 10 mg por vía oral de everolimus diario, durante una mediana de 71,5 meses. Evaluamos los parámetros como: tasa y duración de la respuesta; reducción del volumen renal y las lesiones; prevención de complicaciones, toxicidad presentada y causa.ResultadosConfirmamos la efectividad del tratamiento en cuatro pacientes jóvenes, con AMLr renales bilaterales, múltiples, de 12 (5 a 19) cm de diámetro máximo como mediana, desde junio del 2013 hasta la actualidad, con una reducción continua del tamaño de las lesiones, descenso del 30% del volumen, en el 75% al sexto mes y del 50% en la mitad de los sujetos después dos años, permaneciendo aún en respuesta. No se presentaron complicaciones como sangrado o deterioro del filtrado glomerular a largo plazo, con un perfil de seguridad favorable, sin interrupciones y con efectos adversos no acumulativos leves a moderados, en su mayoría durante el primer año de tratamiento.ConclusiónEverolimus es una opción terapéutica segura y eficaz para el AMLr y para diversas manifestaciones del CET, que se reproduce en la vida real, con seis años de seguimiento. (AU)

Introduction: Renal angiomyolipoma is a frequent manifestation of Tuberous Sclerosis Complex (TSC), for which everolimus therapy has been recently established as a novel non-invasive therapeutic option. As there are limited real life and long-term data, the analysis of our experience provides added value in terms of safety and efficacy.Material and methodsDescriptive analysis of our experience in patients with giant bilateral renal angiomyolipomas, in the context of TSC, treated with 10 mg oral everolimus daily, during a median of 71.5 months. We evaluated the following parameters: response rate and duration, reduction of kidney size and lesions, prevention of complications and presentation of toxicity and its cause.ResultsWe confirm the effectiveness of treatment in 4 young patients, with multiple, bilateral angiomyolipomas of a median of 12 (5-19) cm maximum diameter, from June 2013 to date, after continuous reduction in lesion size, a decrease of 30% of the volume in 75% at six months and 50% in half of the subjects at two years, still showing drug response. Absence of complications such as bleeding or glomerular filtration rate decline in the long term, with a favorable safety profile, without interruptions and with mild-moderate, non-cumulative adverse effects, mostly within the first year of treatment.ConclusionEverolimus is a safe and effective therapeutic option for renal angiomyolipoma and various manifestations of TSC, which has been reproduced in real life with six years of follow-up. (AU)

Renal angiomyolipoma and tuberous sclerosis complex: long-term safety and efficacy outcomes of Everolimus therapy. / Angiomiolipoma renal y complejo esclerosis tuberosa: resultados a largo plazo en seguridad y eficacia de terapia con everolimus.

INTRODUCTION: Renal angiomyolipoma is a frequent manifestation of Tuberous Sclerosis Complex (TSC), for which everolimus therapy has been recently established as a novel non-invasive therapeutic option. As there are limited real life and long-term data, the analysis of our experience provides added value in terms of safety and efficacy. MATERIAL AND METHODS: Descriptive analysis of our experience in patients with giant bilateral renal angiomyolipomas, in the context of TSC, treated with 10 mg oral everolimus daily, during a median of 71.5 months. We evaluated the following parameters: response rate and duration, reduction of kidney size and lesions, prevention of complications and presentation of toxicity and its cause. RESULTS: We confirm the effectiveness of treatment in 4 young patients, with multiple, bilateral angiomyolipomas of a median of 12 (5-19) cm maximum diameter, from June 2013 to date, after continuous reduction in lesion size, a decrease of 30% of the volume in 75% at six months and 50% in half of the subjects at two years, still showing drug response. Absence of complications such as bleeding or glomerular filtration rate decline in the long term, with a favorable safety profile, without interruptions and with mild-moderate, non-cumulative adverse effects, mostly within the first year of treatment. CONCLUSION: Everolimus is a safe and effective therapeutic option for renal angiomyolipoma and various manifestations of TSC, which has been reproduced in real life with six years of follow-up.

Nasolabial flap reconstruction for orofacial defects: A case series

Objective@#To describe our clinical experience with, and functional outcomes of the nasolabial flap for reconstruction of orofacial defects. @*Methods@#Design: Retrospective Case Series. Setting: Tertiary National University Hospital. Participants: Records of 11 patients on whom a nasolabial flap was performed for reconstruction of head and neck defects between January 2013 and December 2018 were analyzed.@*Results@#All patients underwent wide excision with or without frozen section, with or without neck dissection, and nasolabial flap closure was performed by a single surgeon. There were no major complications. In two cases, the nasolabial flap was used as an adjunct for Abbé and deltopectoral flap reconstruction. One had poor oral competence due to the bulk of the deltopectoral flap. Acceptable aesthetics and functional outcomes were achieved. @*Conclusion@#The nasolabial flap is a viable alternative for reconstruction of orofacial defects following head and neck surgeries. Additional cases can help validate our initial experience

Temporal Bone Chondroblastoma: Systematic Review of Clinical Features and Outcomes.

OBJECTIVE: Chondroblastoma is an uncommon benign neoplasm of cartilaginous origin usually involving the long bones. The temporal bone is a rare location for this tumor. The clinical profile, optimal medical and surgical management, and outcomes of treatment for temporal bone chondroblastoma remain unknown. METHODS: We performed a systematic review of the SCOPUS, PubMed, and CENTRAL databases for case reports and case series on patients with histopathologically proven temporal bone chondroblastoma. Data on demographics, clinical manifestation, surgical management, adjuvant treatment, and outcome on last follow-up were collected. RESULTS: A total of 100 cases were reported in the literature, including one described in the current study. The mean age of patients was 42.3 years (range, 2-85 years), with a slight male predilection (1.3:1). The most common clinical manifestations were otologic symptoms (e.g., hearing loss [65%], tinnitus, and otalgia) and a palpable mass. Surgical excision was performed in all cases, with gross total excision achieved in 58%. Radiation therapy was performed in 18% of cases, mostly as adjuvant treatment after subtotal excision. There were no deaths at a median follow-up of 2 years. Among the patients with detailed status on follow-up, 58% had complete neurologic recovery, 38% had partial recovery, and 4% had progression of symptoms as a result of tumor recurrence. CONCLUSIONS: Temporal bone chondroblastoma has a distinct clinical profile from chondroblastoma of long bones. Surgery is the mainstay of treatment, and radiation therapy may be given after subtotal excision. Outcomes are generally favorable after treatment.

A dysfunctional Larynx dilemma: Carcinoma recurrence or radiation-induced damage?

@#A 61-year-old male diagnosed with laryngeal squamous cell carcinoma presented with hoarseness, progressive dysphagia leading to aspiration, and dyspnea one month after definitive radiation therapy. Examination revealed a diffusely swollen glottis, paralyzed vocal cords, and post-radiation fibrosis. Several glottic biopsies yielded results negative for malignancy and favored radiation-induced changes. When presented with the option of further diagnostic testing with a positron emission tomography (PET) scan or an outright laryngectomy, the patient decided on the latter. Final histopathologic diagnosis was negative for recurrence of malignancy. This case demonstrates treatment dilemmas for patients with laryngeal carcinoma with uncertain recurrence wherein radical surgical management may prove to be a viable option to achieve both diagnostic certainty and ultimate relief of symptoms.

Prognostic value of thyroidectomy and tracheostomy in anaplastic thyroid carcinoma

@#<p><strong>OBJECTIVE:</strong> To determine the prognostic value of surgical interventions done among patients with anaplastic thyroid carcinoma (ATC)</p><p><strong>METHODS:</strong> A five-year retrospective chart review of 25 patients was done and baseline characteristics determined. Patients discharged alive as of the time of last chart entry were followed up by phone interview or personal visit. Overall survival was the main outcome measure which was plotted as Kaplan-Meier estimates and compared via log-rank test. The incidence of complications surrounding tracheostomy and thyroidectomy were also noted.</p><p><strong>Methods: </strong></p><p><strong>Design:</strong> Ambispective Cohort Study</p><p><strong>Setting:</strong> Tertiary National University Hospital</p><p><strong>Participants:</strong> All private and public (charity) patients seen at the wards or clinics diagnosed with ATC via fine needle cytology or tissue histopathology.</p><p><strong>RESULTS:</strong> All patients presented with either stage IV-B or stage IV-C disease. A significant difference in survival curves was noted when comparing between the two stages (p<.05). Subgroup analysis per stage revealed no significant difference in overall survival when comparing patients who did not undergo surgery, those who underwent tracheostomy or those who underwent thyroidectomy for both IV-B (p=.244) or IV-C (p=.165) disease. The incidence of complications for tracheostomy was 60%, the most common being mucus plugging. For thyroidectomy, the incidence of complications was 80% with hypocalcemia being the most common.</p><p><strong>CONCLUSION:</strong> The current available data fails to demonstrate any significant survival advantage of tracheostomy or thyroidectomy when performed among similarly staged patients.</p>

Maxillary sinus squamous cell carcinoma in a tertiary hospital in the Philippines

@#<p><strong>Objective:</strong> To establish preliminary demographic and clinicopathologic data on Maxillary Sinus Squamous Cell Carcinoma (SCC) in the Philippine General Hospital</p><p><strong>Methods:</strong>       </p><p><strong>Design:</strong>           Retrospective Case Series</p><p><strong>Setting:</strong>           Tertiary National University Hospital</p><p><strong>Participants:</strong> Socio-demographic and clinical data from records of 22 patients admitted at the Department of Otorhinolaryngology of the Philippine General Hospital from 2013-2016 and histopathologically confirmed to have Maxillary Sinus SCC, were collected and described using means and proportions.</p><p><strong>Results:</strong> There were 15 males and 7 females with a mean age of 50-years-old (range 24 to 77-years-old). Maxillary mass/swelling was the most common chief complaint.  The mean gap between initial symptoms and consult was 6.77 months.  Initial biopsies were obtained from the maxillary sinus in 16 patients, with 1 patient noted to have undergone malignant transformation from a prior intranasal squamous papilloma.  Staging was advanced (Stage IVA in 16, IVB in 4, and III in 2), with no patients with Stage I or II disease.  Sixteen (16) patients underwent surgery and radiotherapy, while 6 patients received radiotherapy (RT) with or without chemotherapy.  Regional and distant metastases were uncommon.</p><p><strong>Conclusion:</strong> In this series, maxillary sinus SCC occurs more in males, with a maxillary mass as the most common chief complaint.  Delay in treatment is common, with a mean gap of 6 months between initial symptoms and consult.  Neck node metastasis is uncommon, and most patients undergo surgery with radiotherapy as treatment.</p><p> </p><p><strong>Keywords:</strong> maxillary sinus cancer; paranasal sinus cancer; squamous cell carcinoma</p>

Intraosseus arteriovenous malformation of the mandible: extracorporeal curettage and immediate replantation

@#<p><strong>OBJECTIVE:</strong> To describe a surgical technique in the treatment of arteriovenous malformations of the mandible</p><p><strong>METHODS:</strong></p><p>       <strong>Design:</strong>    Case Report</p><p><strong>       Setting:</strong>    Tertiary National University Hospital</p><p>       <strong>Participant:</strong>        One</p><p><strong>RESULT:</strong> A 16-year-old boy underwent resection, extracorporeal curettage, and immediate replantation of the hemimandible for intraosseous arteriovenous malformation. Postoperative follow up and imaging at one- and six-months showed no signs of recurrence, new bone formation and consolidation of the replanted right mandible with good symmetry and function.</p><p><strong>CONCLUSION:</strong> Extracorporeal curettage followed by immediate replantation of the resected mandible seems to have yielded good early results in our case and may be a viable alternative especially when access to highly specialized microvascular surgical services is limited.</p><p> </p>

Surgical simulation of endoscopic sinus surgery using Thiel soft-embalmed human cadaver

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> This study describes the quality of Thiel soft-embalmed cadavers as training model for endoscopic sinus surgery in terms of color and consistency of the tissues and similarity of performing the surgical steps to live surgery.</p><p style="text-align: justify;"><strong>METHODS:</strong> This is a cross-sectional descriptive study. Six Thiel soft-embalmed cadavers from the University of the Philippines, College of Medicine, Department of Anatomy were used as training models. The Thiel-preserved cadavers utilized the soft embalming protocol being employed at the Virginia State Anatomical Program in Richmond, Virginia, USA. Ten otorhinolaryngologists were recruited to evaluate the cadavers using a questionnaire with three parts. The first two parts utilize a 10-point Likert scale with 1 as the least similar to live patient while 10 as simulating the live patient. The third part is an open-ended question regarding the suitability of Thiel soft-embalmed cadavers in the training for endoscopic sinus surgery.</p><p style="text-align: justify;"><strong>RESULTS:</strong> Endoscopic sinus surgery was successfully performed in all cadavers. The Thiel soft-embalmed cadaver closely replicates the color and consistency of the anatomic structures important in endoscopic sinus surgery. All the surgical steps were performed with ease simulating live surgery.</p><p style="text-align: justify;"><strong>CONCLUSION:</strong> Thiel soft-embalmed cadaver is a suitable model for training in endoscopic sinus surgery.</p>

Tumoral calcinosis in secondary hyperparathyroidism

@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> To  report  a  case  of  tumoral  calcinosis  from  secondary hyperparathyroidism  and  to describe its surgical management.<br /><strong>METHODS:</strong><br /><strong> Design:</strong> Case Report<br /> <strong>Setting:</strong> Tertiary Public University Hospital<br /> <strong>Patient:</strong> One<br /><strong>RESULTS:</strong> A 34-year-old woman presented with progressively-enlarging bilateral upper extremity masses. Diagnostic tests revealed hyperfunctioning parathyroid glands. The patient underwent subtotal  parathyroidectomy,  right  thyroid  lobectomy  with  isthmusectomy,  and  transcervical thymectomy.    Follow-up  revealed  marked  decrease  in  parathyroid  hormone,  and  progressive resolution of the tumoral calcinosis.<br /><strong>CONCLUSION:</strong> Subtotal  parathyroidectomy  and  transcervical  thymectomy  have  a  role  in  the management  of  tumoral  calcinosis,  and  in  this  case  led  to  excellent  post-operative  results. The rare  presentation  of  secondary  hyperparathyroidism  and  intervention  in  this  patient  may  have potential lessons for future management of similar cases.</p>

Qualitative and quantitative analysis of a group of volatile organic compounds in biological samples by HS-GC/FID: application in practical cases.

A simple and sensitive procedure, using n-propanol as internal standard (IS), was developed and validated for the qualitative and quantitative analysis of a group of 11 volatile organic substances with different physicochemical properties (1-butanol, 2-propanol, acetaldehyde, ethyl acetate, acetone, acetonitrile, chloroform, diethyl ether, methanol, toluene and p-xylene) in whole blood, urine and vitreous humor. Samples were prepared by dilution with an aqueous solution of internal standard followed by Headspace Gas Chromatography with a Flame-ionization Detector (HS GC-FID) analysis. Chromatographic separation was performed using two capillary columns with different polarities (DB-ALC2: 30m×0.320mm×1.2µm and DB-ALC1: 30m×0.320mm×1.8µm), thus providing a change in the retention and elution order of volatiles. This dual column confirmation increases the specificity, since the risk of another substance co-eluting at the same time in both columns is very small. The method was linear from 5 to 1000mg/L for toluene and p-xylene, 50-1000mg/L for chloroform, and 50-2000mg/L for the remaining substances, with correlation coefficients of over 0.99 for all compounds. The limits of detection (LOD) ranged 1 to 10mg/L, while the limits of quantification (LOQ) ranged from 2 to 31mg/L. The intra-day precision (CV<6.4%), intermediate precision (CV<7.0%) and accuracy (relative error ±10%) of the method were in conformity with the criteria normally accepted in bioanalytical method validation. The method developed has been applied to forensic cases, with the advantages that it uses a small sample volume and does not require any extraction procedure as it makes use of a headspace injection technique.

Effects of ionizing radiation and preservation on biomechanical properties of human costal cartilage.

Tissue banks around the world store human cartilage obtained from cadaveric donors for use in diverse reconstructive surgical procedures. To ensure this tissue is sterile at the time of distribution, tissues may be sterilized by ionizing radiation. In this work, we evaluate the physical changes in deep frozen costal cartilage (-70 °C) or costal cartilage preserved in high concentrations of glycerol (>98 %) followed by a terminal sterilization process using ionizing radiation, at 3 different doses (15, 25 and 50 kGy). Tension and compression tests were carried out to determine the mechanical changes related both to the different preservation methods and irradiation doses. For both methods of preservation, tension strength was increased by about 24 %, when cartilage tissue was irradiated with 15 kGy. Deep frozen samples, when irradiated with 25 or 50 kGy, had a decrease in their mechanical performance, albeit to a lesser extent than when tissues were preserved in high concentration of glycerol and equally irradiated. In conclusion, processing in high concentration of glycerol did not increase tissue protection against radiation damage; while cartilage preserved in high concentrations of glycerol withstands radiation up to 25 kGy, deep frozen human costal cartilage may be sterilized with a doses up to 50 kGy without significant mechanical impact.