Theoretical Study of Cyanidin-Resveratrol Copigmentation by the Functional Density Theory.

Anthocyanins are colored water-soluble plant pigments. Upon consumption, anthocyanins are quickly absorbed and can penetrate the blood-brain barrier (BBB). Research based on population studies suggests that including anthocyanin-rich sources in the diet lowers the risk of neurodegenerative diseases. The copigmentation caused by copigments is considered an effective way to stabilize anthocyanins against adverse environmental conditions. This is attributed to the covalent and noncovalent interactions between colored forms of anthocyanins (flavylium ions and quinoidal bases) and colorless or pale-yellow organic molecules (copigments). The present work carried out a theoretical study of the copigmentation process between cyanidin and resveratrol (CINRES). We used three levels of density functional theory: M06-2x/6-31g+(d,p) (d3bj); ωB97X-D/6-31+(d,p); APFD/6-31+(d,p), implemented in the Gaussian16W package. In a vacuum, the CINRES was found at a copigmentation distance of 3.54 Å between cyanidin and resveratrol. In water, a binding free energy ∆G was calculated, rendering -3.31, -1.68, and -6.91 kcal/mol, at M06-2x/6-31g+(d,p) (d3bj), ωB97X-D/6-31+(d,p), and APFD/6-31+(d,p) levels of theory, respectively. A time-dependent density functional theory (TD-DFT) was used to calculate the UV spectra of the complexes and then compared to its parent molecules, resulting in a lower energy gap at forming complexes. Excited states' properties were analyzed with the ωB97X-D functional. Finally, Shannon aromaticity indices were calculated and isosurfaces of non-covalent interactions were evaluated.

A murine model for the del(GJB6-D13S1830) deletion recapitulating the phenotype of human DFNB1 hearing impairment: generation and functional and histopathological study.

Inherited hearing impairment is a remarkably heterogeneous monogenic condition, involving hundreds of genes, most of them with very small (< 1%) epidemiological contributions. The exception is GJB2, the gene encoding connexin-26 and underlying DFNB1, which is the most frequent type of autosomal recessive non-syndromic hearing impairment (ARNSHI) in most populations (up to 40% of ARNSHI cases). DFNB1 is caused by different types of pathogenic variants in GJB2, but also by large deletions that keep the gene intact but remove an upstream regulatory element that is essential for its expression. Such large deletions, found in most populations, behave as complete loss-of-function variants, usually associated with a profound hearing impairment. By using CRISPR-Cas9 genetic edition, we have generated a murine model (Dfnb1em274) that reproduces the most frequent of those deletions, del(GJB6-D13S1830). Dfnb1em274 homozygous mice are viable, bypassing the embryonic lethality of the Gjb2 knockout, and present a phenotype of profound hearing loss (> 90 dB SPL) that correlates with specific structural abnormalities in the cochlea. We show that Gjb2 expression is nearly abolished and its protein product, Cx26, is nearly absent all throughout the cochlea, unlike previous conditional knockouts in which Gjb2 ablation was not obtained in all cell types. The Dfnb1em274 model recapitulates the clinical presentation of patients harbouring the del(GJB6-D13S1830) variant and thus it is a valuable tool to study the pathological mechanisms of DFNB1 and to assay therapies for this most frequent type of human ARNSHI.

Treatment of distal third humeral shaft fractures with posterior minimally invasive plate osteosynthesis (MIPO) with segmental isolation of the radial nerve: minimum one-year follow-up.

Background: Open reduction and internal fixation with plate is one of the most widely used treatments for distal third humeral shaft fractures. The purpose of this study was to report the outcomes of the treatment of distal third humeral shaft fractures with posterior minimally invasive plate osteosynthesis (MIPO) with segmental isolation of the radial nerve. Methods: We performed an observational, retrospective, consecutive, monocentric, continuous multioperator study. We reviewed 22 distal third humeral shaft fractures treated with posterior MIPO in our institution with an extra-articular distal humerus plate from 2018 to 2021. Inclusion was limited to functionally independent patients with displaced fractures involving the junction of the middle and distal thirds of the humerus and minimum 12-month follow-up for implant removal. We assessed clinical outcomes including range of motion; QuickDASH score; Mayo Elbow Performance Score; and Constant-Murley score. Results: The average follow-up period of the sample was 31.7 ± 11.6 months (range, 15.7-51.3 months). The average elbow flexion and extension were 146.4° ± 7.3° (range, 120°-150°) and -0.7° ± 3.3° (range, -15° to 0°), respectively. The average shoulder anterior flexion, elevation, and abduction were 178.6° ± 3.6° (range, 170°-180°), 179.1° ± 2.9° (range, 170°-180°), and 140.9° ± 14.8° (range, 110°-160°), respectively. The average external rotation was 88.6° ± 6.4 (range, 65°-90°). The mean visual analog scale score for pain was 1.0 ± 1.6 (range, 0-5) and the mean Mayo Elbow Performance Score was 90.5 ± 9.9 (range, 70-100). The mean QuickDASH and Constant-Murley scores were 4.7 ± 6.8 (range, 0-20.5) and 95.5 ± 5.1 (range, 81-100), respectively. Two patients presented with relevant compromise of radial nerve motor function postoperatively (M3 and M2; the more compromised was preoperative injury). All patients recovered radial nerve neuropraxia within six weeks postoperatively. All fractures achieved union. The average anteroposterior and lateral axis were 175.0 ± 3.6 (168.0°-180.0°) and 177.5 ± 2.0 (173.0°-180.0°), respectively. No superficial or deep infection was reported. No cases of re-displacement of fracture, implant failure, or any other implant-related complication in follow-up were reported. No patient required plate withdrawal. Conclusion: The results of this study demonstrate that the posterior MIPO technique is a reliable option for treating distal third shaft humeral fractures. The radial nerve must be identified and protected in all cases to prevent palsy.

Straight antegrade humeral nailing and risk of iatrogenic injury of supraspinatus tendon footprint: An MRI study.

Background: Straight antegrade humeral nailing (SAHN) is associated with excellent clinical results in proximal humerus fractures. The optimal entry point is the top of the humeral head. However, the anatomy is variable, and the entry point can affect supraspinatus tendon footprint (SSP-F) or fracture reduction. The aim of this study was to analyze the relationship between the SSP-F and SAHN entry point by analyzing magnetic resonance imaging (MRI) studies of the humerus. Methods: In total 58 MRI studies of entire humerus were reviewed. The mean age was 51.6 ± 12.4 years, with 40 female patients. The distance between the SSP-F and the SAHN insertion point (critical distance: CD), the width of the footprint, and the neck-shaft angle (NSA) were measured. Univariate and multivariate analysis were performed. Results: The mean CD was 7.51 mm ± 2.81 (0-12.9 mm) with 51.7% of proximal humerus "critical type" (CD <8 mm). The CD was found to be lower in females, with no difference found with varying age (62.5% "critical type"). CD correlated with NSA (linear regression). "Critical type" correlated with female gender and NSA (logistic regression). Discussion: More than half of the humerus are "critical types" as to SAHN and may, therefore, be at risk for procedure-related complications.

The Reverse Shoulder Arthroplasty Angle in MRI: Impact of the Articular Cartilage in the Estimated Inclination of the Inferior Glenoid.

Purpose: To describe the reverse shoulder arthroplasty angle (RSA angle) in magnetic resonance imaging (MRI) and compare the angle formed using bony landmarks (Bony RSA angle or B-RSA angle) with another angle formed using the cartilage margin as reference (Cartilage RSA angle or C-RSA angle). Methods: Adult patients with a shoulder MRI obtained in our hospital between July 2020 and July 2021 were included. The C-RSA angle and B-RSA angle were measured. All images were independently assessed by 4 evaluators. Intraclass correlation coefficient (ICC) was determined for the B-RSA and C-RSA to evaluate interobserver agreement. Results: A total of 61 patients were included with a median age of 59 years (17-77). C-RSA angle was significantly higher than B-RSA (25.4° ± 0.7 vs 19.5° ± 0.7, respectively) with a P-value <.001. The overall agreement was considered "good" for C-RSA (ICC = 0.74 [95% CI 0.61-0.83]) and "excellent" for B-RSA angle (ICC = 0.76 [95% CI 0.65-0.85]). Conclusions: C-RSA angle is significantly higher than B-RSA angle. In cases without significant glenoid wear neglecting to account for the remaining articular cartilage at the inferior glenoid margin may result in superior inclination of standard surgical guides.

Predicting COVID-19 cases using SARS-CoV-2 RNA in air, surface swab and wastewater samples.

Genomic footprints of pathogens shed by infected individuals can be traced in environmental samples, which can serve as a noninvasive method of infectious disease surveillance. The research evaluates the efficacy of environmental monitoring of SARS-CoV-2 RNA in air, surface swabs and wastewater to predict COVID-19 cases. Using a prospective experimental design, air, surface swabs, and wastewater samples were collected from a college dormitory housing roughly 500 students from March to May 2021 at the University of Miami, Coral Gables, FL. Students were randomly screened for COVID-19 during the study period. SARS-CoV-2 concentration in environmental samples was quantified using Volcano 2nd Generation-qPCR. Descriptive analyses were conducted to examine the associations between time-lagged SARS-CoV-2 in environmental samples and COVID-19 cases. SARS-CoV-2 was detected in air, surface swab and wastewater samples on 52 (63.4 %), 40 (50.0 %) and 57 (68.6 %) days, respectively. On 19 (24 %) of 78 days SARS-CoV-2 was detected in all three sample types. COVID-19 cases were reported on 11 days during the study period and SARS-CoV-2 was also detected two days before the case diagnosis on all 11 (100 %), 9 (81.8 %) and 8 (72.7 %) days in air, surface swab and wastewater samples, respectively. SARS-CoV-2 detection in environmental samples was an indicator of the presence of local COVID-19 cases and a 3-day lead indicator for a potential outbreak at the dormitory building scale. Proactive environmental surveillance of SARS-CoV-2 or other pathogens in multiple environmental media has potential to guide targeted measures to contain and/or mitigate infectious disease outbreaks within communities.

Establishing safe zones to avoid nerve injury in the posterior minimally invasive plate osteosynthesis for humerus fractures: a magnetic resonance imaging study.

Background: Safety zones to avoid nerve injury at proximal incision of posterior minimally invasive plate osteosynthesis for humerus fracture have been scarcely studied. The purpose of this study was to describe the location of axillary and radial nerves (RN) in magnetic resonance imaging to establish safety zones. Methods: Fifty-two magnetic resonance imaging studies of the entire humerus were reviewed. The mean age was 50.6 ± 12.1 years, with 37 female patients. The distance of the axillary nerve (AN; distal portion, humeral midpoint) and RN (medial border, midpoint, and lateral border of the humerus) was measured in relation to the posterolateral acromion angle, acromioclavicular axis, and transepicondylar axis. Univariate analysis (Student's t test) and a multivariate analysis (linear regression) were performed. P values < .05 were considered significant. Results: The AN location at the humerus was 54.9 ± 6.4 mm (20.1% humeral length [HL]) in relation to posterolateral acromion angle and 63.2 ± 6.1 mm (23.2% HL) in relation to acromioclavicular axis. The RN location was 100.2 ± 17.1 mm (36.6% HL) at the humerus medial border, 118.0 ± 21.5 mm (43.1% HL) at the humerus midpoint, and 146.0 ± 24.4 mm (53.6% HL) at the humerus lateral border. In relation to transepicondylar axis, it was 175.4 ± 15.6 mm (64.3% HL), 156.0 ± 19.0 mm (57.2% HL), and 127.4 ± 21.2 mm (46.7% HL), respectively. Nerves location was related to HL, independent of gender. Conclusion: The main finding of our study is that the location of the AN and RN in relation to the humerus is related to the HL and can be used to predictably define the safe zones to avoid nerve injury in the proximal incision of posterior minimally invasive plate osteosynthesis for humerus fractures.

Critical shoulder angle and failure of conservative treatment in patients with atraumatic full thickness rotator cuff tears.

BACKGROUND: Atraumatic full thickness rotator cuff tears (AFTRCT) are common lesions whose incidence increases with age. Physical therapy is an effective conservative treatment in these patients with a reported success rate near 85% within 12 weeks of treatment. The critical shoulder angle (CSA) is a radiographic metric that relates the glenoid inclination with the lateral extension of the acromion in the coronal plane. A larger CSA has been associated with higher incidence of AFTRCT and a higher re-tear rate after surgical treatment. However, no study has yet described an association between a larger CSA and failure of conservatory treatment in ARCT. The main objective of this study is to determine whether there is an association between CSA and failure of physical therapy in patients with AFTRCT. METHODS: We reviewed the imaging and clinical records of 48 patients (53 shoulders), 60% female, with a mean age of 63.2 years (95% CI ± 10.4 years); treated for AFTRCT who also underwent a true anteroposterior radiograph of the shoulder within a year of diagnosis of the tear. We recorded demographic (age, sex, type of work), clinical (comorbidities), and imaging data (CSA, size and location of the tear). We divided the patients into two groups according to success or failure of conservative treatment (indication for surgery), so 21 shoulders (39.6%) required surgery and were classified as failure of conservative treatment. Univariate and multivariate analysis was performed to detect predictors of failure of conservative treatment. RESULTS: The median CSA was 35.5º with no differences between those with failure (median 35.5º, range 29º to 48.2º) and success of conservative treatment (median 35.45º, range 30.2º to 40.3º), p = 0.978. The multivariate analysis showed a younger age in patients with failure of conservative treatment (56.14 ± 9.2 vs 67.8 ± 8.4, p < 0.001) and that male gender was also associated with failure of conservative treatment (57% of men required surgery vs 28% of women, p = 0.035). CONCLUSIONS: It is still unclear if CSA does predict failure of conservative treatment. A lower age and male gender both could predicted failure of conservative treatment in AFTRCT. Further research is needed to better address this subject.

COVID-19 Prediction using Genomic Footprint of SARS-CoV-2 in Air, Surface Swab and Wastewater Samples.

Importance: Genomic footprints of pathogens shed by infected individuals can be traced in environmental samples. Analysis of these samples can be employed for noninvasive surveillance of infectious diseases. Objective: To evaluate the efficacy of environmental surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) for predicting COVID-19 cases in a college dormitory. Design: Using a prospective experimental design, air, surface swabs, and wastewater samples were collected from a college dormitory from March to May 2021. Students were randomly screened for COVID-19 during the study period. SARS-CoV-2 in environmental samples was concentrated with electronegative filtration and quantified using Volcano 2 nd Generation-qPCR. Descriptive analyses were conducted to examine the associations between time-lagged SARS-CoV-2 in environmental samples and clinically diagnosed COVID-19 cases. Setting: This study was conducted in a residential dormitory at the University of Miami, Coral Gables campus, FL, USA. The dormitory housed about 500 students. Participants: Students from the dormitory were randomly screened, for COVID-19 for 2-3 days / week while entering or exiting the dormitory. Main Outcome: Clinically diagnosed COVID-19 cases were of our main interest. We hypothesized that SARS-CoV-2 detection in environmental samples was an indicator of the presence of local COVID-19 cases in the dormitory, and SARS-CoV-2 can be detected in the environmental samples several days prior to the clinical diagnosis of COVID-19 cases. Results: SARS-CoV-2 genomic footprints were detected in air, surface swab and wastewater samples on 52 (63.4%), 40 (50.0%) and 57 (68.6%) days, respectively, during the study period. On 19 (24%) of 78 days SARS-CoV-2 was detected in all three sample types. Clinically diagnosed COVID-19 cases were reported on 11 days during the study period and SARS-CoV-2 was also detected two days before the case diagnosis on all 11 (100%), 9 (81.8%) and 8 (72.7%) days in air, surface swab and wastewater samples, respectively. Conclusion: Proactive environmental surveillance of SARS-CoV-2 or other pathogens in a community/public setting has potential to guide targeted measures to contain and/or mitigate infectious disease outbreaks. Key Points: Question: How effective is environmental surveillance of SARS-CoV-2 in public places for early detection of COVID-19 cases in a community?Findings: All clinically confirmed COVID-19 cases were predicted with the aid of 2 day lagged SARS-CoV-2 in environmental samples in a college dormitory. However, the prediction efficiency varied by sample type: best prediction by air samples, followed by wastewater and surface swab samples. SARS-CoV-2 was also detected in these samples even on days without any reported cases of COVID-19, suggesting underreporting of COVID-19 cases.Meaning: SARS-CoV-2 can be detected in environmental samples several days prior to clinical reporting of COVID-19 cases. Thus, proactive environmental surveillance of microbiome in public places can serve as a mean for early detection of location-time specific outbreaks of infectious diseases. It can also be used for underreporting of infectious diseases.

Glenoid neck length in a healthy population and its association with scapular notching.

BACKGROUND: Scapular notching is a radiographic finding associated with the use of a reverse shoulder prosthesis. The morphological characteristics of the glenoid neck have been scarcely explored as a relevant factor in relation to scapular notching. The objective of this study is to measure the length of the glenoid neck in a three-dimensional CT reconstruction of a healthy population and to simulate the scapular notching free range of motion for the "long neck" and for the "short neck" groups. METHODS: CT scans of 214 shoulders were reviewed, excluding incomplete, poor quality, or altered studies. 100 CT scans were finally processed. The mean age was 51.7 years (SD 19.4; range, 15-84 years), with 49 female and 51 male patients. For each of the scapulae, four morphometric measurements were obtained: anterior glenoid neck (AGN), middle glenoid neck (MGN), posterior glenoid neck (PGN) and alternative posterior glenoid neck (aPGN). Using 3D software, we simulated a reverse shoulder prosthesis, and the scapular notching free range of motion was registered. Differences between measurements were evaluated with an unpaired t-test using StataIC16®. P-values < 0.05 were considered significant. The intraobserver and interobserver correlation was evaluated with the intraclass correlation coefficient. RESULTS: The AGN measured 7.43 ± 2.52 mm (range, 1.72-13.3 mm); MGN measured 8.05 mm ± 1.93 (range, 2.92-13.2 mm); PGN measured 7.26 ± 2.6 mm (range, 2-13.4 mm); and aPGN measured 8.97 ± 2.3 mm (range, 4.08-15.4 mm). The scapular notching free range of motion for the "long neck" group was 74.98° ± 7.35 (range, 55-83°) and for the "short neck" group, it was 62.93° ± 6.84 (range, 45-70°) (p = 0.0004). CONCLUSIONS: Measurement of posterior glenoid neck length exhibits excellent reliability and reproducibility, as well as being associated to the scapular notching free range of motion. STUDY DESIGN: Basic, retrospective, CT images research.

Increasing incidence of rotator cuff surgery: A nationwide registry study in Chile.

BACKGROUND: The rotator cuff surgery (RCS) incidence is rising rapidly in North America, Europe, Asia, and Australia. Despite this, multiple factors limit patients' access to surgery. In Latin America, barriers to orthopedic surgery have been largely ignored. The purpose of this study was to calculate the rate of RCS in Chile between 2008 and 2018, investigating possible associated factors to access such as age, sex, and the health insurance. METHODS: An ecological study was carried out with nationwide data obtained from the Database of Hospital Discharges of the Department of Statistics. All Chilean inhabitants aged 25 years or more were included. We used the ICD-10 codes M751, M754, and S460. The annual incidence rate of surgeries and the incidence rate for the period studied per 100,000 inhabitants were calculated. Data were analyzed stratified by age, sex, year of study, and the health insurance. Negative binomial regression was used to compare rates. Statistical analyzes were performed with Stata v.14 software. RESULTS: 39,366 RCSs were performed, with a total rate for the period of 32.36 per 100,000 inhabitants. The annual rate of surgeries from 2008 to 2018 increased from 24.55 to 49.11 per 100,000/year. When adjusting for year, an annual increase in surgery rates of 8.19% (95% CI 6.7-9.6) and 101% growth between 2008 and 2018 (95% CI 90-109%, p < 0.001) was observed. When comparing the global rates according to the health insurance, the public system corresponds to 21.3 per 100,000 and the private system to 72 per 100,000, the latter being 3.4-times higher (95% CI 2.7-4.4; p < 0.001). CONCLUSION: RCS rates are increasing in Chile concordantly with previous reports of other western countries. The most important factor associated with RCS rate found was the patients' health insurance, with higher rates observed for the private sector.

Presión y área de contacto en reparación de manguito rotador: una revisión sistemática / Pressure and contact area in rotator cuff repair: a systematic review

OBJETIVO Proporcionar una sinopsis exhaustiva y un análisis de los estudios biomecánicos sobre la magnitud y distribución de la presión en la interfase tendón-huella de las roturas del manguito rotador, informadas en la literatura en los últimos cinco años. MÉTODOS La investigación se realizó de acuerdo con los métodos descritos en el Manual Cochrane. Los resultados se informan de acuerdo con el consenso de Ítems Preferidos de Reporte en Revisiones Sistemáticas y Metaanálisis (Preferred Reporting Items for Systematic Reviews and Meta-Analyses, PRISMA, en inglés). La búsqueda se realizó el 1er de junio de 2020. Se identificaron e incluyeron estudios ex vivo de ciencia básica y estudios biomecánicos publicados, que evaluaran la magnitud y distribución de la presión en la interfase tendón-huella de las roturas del manguito rotador reparadas entre enero de 2015 y junio de 2020. Se realizaron búsquedas sistemáticas en las bases de datos MEDLINE, Embase, Scopus y Google Scholar utilizando los términos y operadores booleanos: (Rotator Cuff OR Supraspinatus OR Infraspinatus OR Subscapularis OR Teres Minor) AND Pressure AND Footprint. En la base de datos Embase, respetando su sintaxis, se utilizó: Rotator Cuff AND Pressure AND Footprint. RESULTADOS Un total de 15 de los 87 artículos encontrados cumplieron con todos los criterios de elegibilidad y se incluyeron en el análisis. CONCLUSIÓN La presión y área de contacto sería optimizada biomecánicamente con una reparación transósea de doble fila equivalente, sin nudos en la hilera medial, y con el uso de cintas para su ejecución, conceptos de reparación específica para roturas delaminadas, y limitación de la abducción en el postoperatorio inmediato.

OBJETIVE To provide a comprehensive synopsis and analysis of biomechanical studies on the magnitude and distribution of pressure at the tendon-footprint interface of rotator cuff tears reported in the literature in the last five years. METHODS The research was performed according to the methods described in the Cochrane Manual. The results are reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) consensus. The search was performed on June 1st, 2020. We identified and included ex vivo basic science studies and published biomechanical studies that evaluated the magnitude and distribution of pressure at the tendon-footprint interface of rotator cuff tears repaired between January 2015 and June 2020. Systematic searches on the MEDLINE, Embase, Scopus and Google Scholar databases were performed using the terms and Boolean operators: (Rotator Cuff OR Supraspinatus OR Infraspinatus OR Subscapularis OR Teres Minor) AND Pressure AND Footprint. In the Embase database, respecting its syntax, the following was used: Rotator Cuff AND Pressure AND Footprint. RESULTS In total, 15 of the 87 articles found fulfilled all the eligibility criteria and were included in the analysis. CONCLUSION The pressure and contact area would be biomechanically optimized with an equivalent transosseous double-row repair, without knots in the medial row, and with the use of tapes for its execution, specific repair concepts for delaminated tears, and a limitation of abduction in the immediate postoperative period.

Mayor presión y área de contacto en reparación transósea cruzada de manguito rotador versus reparación simple / Increased pressure and contact area in rotator cuff crossed versus simple transosseous repair

OBJETIVO: Comparar la presión y el área de contacto en la interfase tendón-huella de una reparación realizada con suturas transóseas simples y cruzadas. MÉTODOS: Se utilizaron doce hombros de cordero para simular una rotura de manguito rotador. Se midió el área de contacto en la interfase tendón-huella con láminas sensibles a presión; luego, se midió la presión con un sensor digital. Se registró la presión basal durante la aplicación de carga cíclica y al final de la intervención. Se compararon 2 reparaciones: 2 túneles transóseos con nudos simples (TOS; n = 6) y 2 túneles transóseos con nudos cruzados (TOC; n = 6), utilizando FiberWire #2. Se realizaron 1.400 ciclos, con una frecuencia 2,5 Hz y una carga de 5 N. Se utilizó la prueba de Mann-Whitney, y ae consideraron significativos valores de p < 0,05. RESULTADOS: La reparación TOS presentó un 50,9 ± 12,7% distribución de presiones en comparación con 72,2 ± 5,3% en la reparación TOC (p < 0,009). La presión promedio en la reparación TOS fue 0,7 ± 0,1 MPa en comparación con 1,1 ± 0,2 MPa en la reparación TOC (p < 0,007). La reparación TOS registró una presión basal de 5,3 ± 5,3 N, presión final de 3,8 ± 4,6 N, y una variación de 51,7 ± 38%. La reparación TOC registró una presión basal de 10,7 ± 1,8 N, presión final de 12,9 ± 8,7 N, y una variación de 114,9 ± 65,9% (p < 0,044; p < 0,022; y p < 0,017, respectivamente). CONCLUSIÓN: La reparación TOC presenta mayor presión a nivel de la interfase tendón-hueso, menor pérdida de fuerza de contacto ante cargas cíclicas, y una mejor distribución de fuerza en la huella al comparar con la reparación TOS, lo que se podría traducir en mejor cicatrización tendínea.

OBJETIVE: To compare the pressure and contact area at the tendon-footprint interface of a repair performed with simple and crossed transosseous sutures. METHODS: Twelve lamb shoulders were used to simulate a rotator cuff tear. The contact area at the tendon-footprint interface was measured with pressure-sensitive films; then, the pressure was measured with a digital sensor. The baseline pressure was recorded during the application of a cyclic load and at the end of the intervention. A total of 2 repairs were compared: 2 transosseous sutures with single knots (STO; n = 6) and 2 transosseous sutures with crossed knots (TOC; n = 6) using FiberWire #2. In total, 1,400 cycles were performed, with a frequency of 2.5 Hz and a load of 5 N. The Mann-Whitney test was used. Values of p < 0.05 were considered significant.RESULTS: The TOS repair presented 50.9 ± 12.7% of pressure distribution compared to 72.2 ± 5.3% in the TOC repair (p < 0.009). The mean pressure in the TOS repair was of 0.7 ± 0.1 MPa compared to 1.1 ± 0.2 MPa in the TOC repair (p < 0.007). The TOS repair registered a basal pressure of 5.3 ± 5.3 N, a final pressure of 3.8 ± 4.6 N, and a variation of 51.7 ± 38%. The TOC repair registered a basal pressure of 10.7 ± 1.8 N, a final pressure of 12.9 ± 8.7 N, and a variation of 114.9 ± 65.9% (p < 0.044; p < 0.022; and p < 0.017 respectively).CONCLUSION: The TOC repair presents higher pressure at the tendon-bone interface, less loss of contact force under cyclic loads, and a better distribution of force on the footprint when compared with the TOS repair, which could translate into better tendon healing.

Abrasión intraósea por sutura según el ángulo del túnel transóseo en huella del manguito rotador / Intraosseous suture abrasion according to the angle of the transosseous tunnel in rotator cuff footprint

OBJETIVO: Comparar el desgaste óseo generado por la abrasión de una carga cíclica entre túneles clásicos oblicuos y perpendiculares. Nuestra hipótesis es la de que el túnel oblicuo presenta un menor desgaste óseo por abrasión cíclica comparado con el túnel perpendicular. MÉTODOS: Ocho hombros congelados de cordero fueron usados para el estudio biomecánico. En cada húmero proximal, dos túneles (oblicuo y perpendicular) fueron generados en la tuberosidad mayor. Se utilizó un sistema de tracción cíclica para traccionar hacia atrás y adelante una sutura trenzada en tensión a través del túnel, midiendo la distancia entre la entrada y la salida de la sutura en el túnel antes y después del proceso de ciclado como medida de perdida de tensión de la sutura. El resultado principal es el cambio de la distancia entre la entrada y la salida de la sutura en el túnel después del ciclado para estimar el desgaste óseo dentro del túnel. Para el análisis estadístico, se utilizó la prueba U de Mann-Whitney. Se consideraron significativos valores de p < 0,05. RESULTADOS: Los túneles perpendiculares tuvieron un 23,24 7,44% de pérdida de longitud, y los túneles oblicuos, 7,76 4,32%. La diferencia de pérdida de longitud fue significativa (p » 0,0003). CONCLUSIÓN: La abrasión ósea generada por el movimiento cíclico de la sutura en el túnel transóseo está influenciada por la geometría del túnel. El desgaste óseo es menor en un túnel oblicuo comparado con un túnel perpendicular. NIVEL DE EVIDENCIA: Estudio de ciencia básica

OBJETIVE: To compare the bone wear generated by the abrasion of a cyclic load between classic oblique and perpendicular tunnels. Our hypothesis is that the oblique tunnel is submitted to less cyclic abrasion bone wear compared with the perpendicular tunnel. METHODS: Eight fresh-frozen lamb shoulders were used for biomechanical testing. In each proximal humerus, two tunnels (one oblique and one perpendicular) were drilled at the greater tuberosity. We used a cyclic traction system to pull back and forth a braided suture under tension through the tunnel, measuring the distance between the entry and exit points of the suture within the tunnel before and after the cyclic process to release the tension in the suture. The main outcome was the percentage of change in the distance between the entry and exit points of the suture within the tunnel before and after cyclic abrasion to estimate the degree of bone wear inside the tunnel. For the statistical analysis, the Mann-Whitney U test was used. Values of p < 0.05 were considered significant. RESULTS: The perpendicular bone tunnels had 23.24 7.44% decrease in length, and the oblique bone tunnels, 7.76 4.32%. The difference in the decrease in length was significant (p » 0.0003). CONCLUSION: The bone abrasion caused by the cyclical movement of the suture in the bone tunnel was influenced by the shape of the tunnel. Bone wear was lower with an oblique tunnel compared with a perpendicular tunnel. LEVEL OF EVIDENCE: Basic Science Study

Estimating glenoid fossa width for instability - related bone loss with CT scan in a Chilean sample / Estimación del ancho de la fosa glenoidea para la pérdida ósea relacionada con inestabilidad con tomografía computarizada en una muestra chilena

SUMMARY: Glenoid fossa bone loss has been associated with recurrence and failure after glenoid labrum repair for shoulder instability. Quantification of glenoid fossa bone loss is critical for the successful treatment of glenohumeral instability. The aim of this paper was to estimate a linear regression model based on glenoid height in CT scan adjusted for age and sex to calculate glenoid fossa width in a healthy Chilean sample. CT scans of 101 shoulders were reviewed. The mean age was 51.96 years (SD 19.16; range, 15-88 years) with 53 females and 48 male patients. Studies with signs of bone loss, instability, fracture, or arthritis were excluded. After 3D-CT reconstruction, the height and width of each glenoid fossa was measured using the Owens methodology. All landmarks for the 2 measurements were placed on the most lateral surface of the glenoid fossa margin. Measurements for all shoulders were recorded by 3 observers and repeated on a subset (n = 20) of shoulders, under blinded conditions, by the same observer, at least 2 weeks after the initial measurements. Descriptive statistics, intraclass correlation and regression coefficients were calculated with Stata BE 17® software. A p- value of 0.05 was considered significant. A linear regression model was estimated resulting in the formula "Width = 10.97 + 0.02 * Age + 0.41 * Height - 1.95 * Sex (1=Female, 0=Male)". This model presented all coefficients with p <0.05 and an adjusted R2 of 0.73. Furthermore, it fulfilled the assumption of linearity, normal distribution of errors, independence of errors, and homoscedasticity. Regarding the intraobserver correlation, ICC was 0.76 for height and 0.91 for width; the interobserver ICC was 0.93 for height and 0.86 for width. A 3D-CT specific formula was developed to predict glenoid fossa width based on height with sufficient accuracy to be clinically valuable.

RESUMEN: La pérdida de hueso de la fosa glenoidea se ha asociado con recurrencia y falla después de la reparación del labrum glenoideo por inestabilidad del hombro. La cuantificación de la pérdida ósea glenoidea es fundamental para el tratamiento exitoso de la inestabilidad glenohumeral. El objetivo de este trabajo fue estimar un modelo de regresión lineal basado en la altura glenoidea en una tomografía computarizada ajustada por edad y sexo para calcular el ancho de la fosa glenoidea en una muestra chilena sana. Se revisaron las tomografías computarizadas de 101 hombros. La edad media fue de 51,96 años (DE 19,16; rango, 15- 88 años) con 53 mujeres y 48 hombres. Se excluyeron los estudios con signos de pérdida ósea, inestabilidad, fractura o artritis. Después de la reconstrucción 3D-CT, se midió la altura y el ancho de cada fosa glenoidea utilizando la metodología de Owens. Todos los puntos de referencia para las 2 mediciones se colocaron en la superficie más lateral del margen glenoideo. Las mediciones de todos los hombros fueron registradas por 3 observadores y repetidas en un subconjunto (n = 20) de hombros, en condiciones ciegas, por el mismo observador, al menos 2 semanas después de las mediciones iniciales. La estadística descriptiva, la correlación intraclase y los coeficientes de regresión se calcularon con el software Stata BE 17®. Se consideró significativo un valor de p de 0,05. Se estimó un modelo de regresión lineal que resultó en la fórmula "Ancho = 10,97 + 0,02 * Edad + 0,41 * Altura - 1,95 * Sexo (1 = Mujer, 0 = Hombre)". Este modelo presentó todos los coeficientes con p <0.05 y un R2 ajustado de 0.73. Además, cumplió con los supuestos de linealidad, distribución normal de errores, independencia de errores y homocedasticidad. En cuanto a la correlación intraobservador, el CCI fue de 0,76 para la altura y 0,91 para la anchura; el ICC interobservador fue de 0,93 para la altura y 0,86 para la anchura. Se desarrolló una fórmula específica de 3D-CT para predecir el ancho glenoideo en función de la altura con suficiente precisión para ser clínicamente valiosa.

Criterios radiográficos para la reducción rotatoria en fracturas diafisarias de húmero / Radiological criteria for rotational reduction in humeral shaft fractures

Introducción: La fractura diafisaria de húmero es frecuente y, en la actualidad, se privilegia el tratamiento quirúrgico. La consolidación en mala rotación puede causar un deterioro de la función y artrosis a largo plazo. Con las técnicas mínimamente invasivas, es difícil manejar la rotación intraoperatoria al no tener una visión directa de la reducción fracturaria. Objetivo: Describir criterios radiográficos para la reducción rotatoria en las fracturas diafisarias de húmero. Materiales y métodos: Estudio retrospectivo de radiografías de húmero comparando criterios radiográficos del húmero distal entre radiografías con rotación interna (sin retroversión proximal) y rotación externa (con retroversión fisiológica). Criterios estudiados: sobreproyección del epicóndilo lateral por sobre el capitellum >50%, esclerosis del borde inferior de la fosa olecraneana, esclerosis del borde lateral de la fosa olecraneana y asimetría de la fosa olecraneana. Resultados: El 97% de las 200 radiografías estudiadas cumplió con los criterios de inclusión y exclusión. Sobreproyección del epicóndilo por sobre el capitellum: 83,3% de los casos; esclerosis del borde inferior de la fosa olecraneana: 30%, esclerosis del borde lateral de la fosa olecraneana: 86,6% y asimetría: 80% de ellas. Todos los criterios con significancia estadística (p <0,001). Al analizar los tres signos positivos en conjunto, la sensibilidad fue del 70% y la especificidad, del 98%; valor predictivo positivo 95,5% y valor predictivo negativo 84,5%. Conclusiones: La rotación humeral correcta es difícil de reproducir en las cirugías mínimamente invasivas, en pacientes con una fractura diafisaria. Describimos cuatro criterios radiográficos que permiten inferir una correcta rotación humeral. Nivel de Evidencia: III

Introduction: Humeral shaft fractures are frequent and surgical treatment is currently favored. Consolidation in malrotation is a complication that can lead to impaired function and long-term osteoarthritis. In minimally invasive techniques, it is difficult to manage intraoperative rotation as there is no direct view of the fracture reduction. Objective: To describe radiological criteria for rotational reduction in humeral shaft fractures. Materials and methods: Retrospective study of humerus radiographs comparing radiological criteria of the distal humerus between radiographs with internal rotation (without proximal retroversion) and radiographs with external rotation (with physiological retroversion). Criteria studied: Overprojection of the lateral epicondyle over the capitellum of more than 50%; sclerosis of the lower border of the olecranon fossa (OF); sclerosis of the lateral border of the OF and asymmetry of the OF. Results: 200 radiographs were studied; 97% met the inclusion and exclusion criteria. Overprojection of the epicondyle over the capitellum was found in 83.3% of the cases. Sclerosis of the inferior border of the OF in 30%, sclerosis of the lateral border of the OF in 86.6%, and asymmetry of OF in 80%. All criteria with statistically significant (p<0.001). When analyzing the 3 positive signs, we found a sensitivity of 70% and a specificity of 98%. The positive predictive value was 95.5% and the negative predictive value was 84.5%. Conclusions: Correct humeral rotation is difficult to reproduce when performing minimally invasive surgeries in patients with a diaphyseal fracture. We describe 4 radiological criteria that allow inferring a correct humeral rotation. Level of Evidence: III

In vitro inhibitory effect of aluminum phthalocyanine tetrasulfonate chloride against Leishmania (Viannia) Peruviana and Leishmania (Viannia) Braziliensis. / Efecto inhibitorio in vitro de la ftalocianina de aluminio tetrasulfonada clorada frente a Leishmania (Viannia) peruviana y Leishmania (Viannia) braziliensis.

OBJECTIVES: To evaluate the in vitro photodynamic activity of aluminum phthalocyanine tetrasulfonate chloride (AlPcClS4) on promastigotes and amastigotes of Leishmania (Viannia) peruviana and Leishmania (Viannia) braziliensis. MATERIALS AND METHODS: The activity of photodynamic therapy using AlPcClS4 on Leishmania promastigote and amastigotes was determined by the Methyl Thiazole Tetrazolium (MTT) colorimetric method and quantitative PCR, respectively. RESULTS: Photodynamic treatment showed an inhibitory effect on promastigotes, particularly on Leishmania (V.) peruviana, to a lesser extent on Leishmania (V.) braziliensis and also on intracellular forms of both species. At 24 hours post-radiation, using concentrations of 200 µM and 350 µM, the inhibitory effect on Leishmania (V.) peruviana was 72.9% and 73.9% respectively; at 96 hours the inhibitory effect was of 78.8% and 80.6%, respectively. Regarding intracellular forms, the inhibitory effect on Leishmania (V.) peruviana amastigotes was 57.8% at 72 hours post-treatment, using a concentration of 200 µM. The IC50 was 56.5, 50, 44 and 39.7 µM, at 24, 48, 72 and 96 hours post-radiation, respectively. CONCLUSIONS: Photodynamic therapy using AlPcClS4 against Leishmania species showed encouraging results, mainly on Leishmania (V.) peruviana, suggesting a potential use as an alternative or complement to the usual treatment of tegumentary leishmaniasis. However, new trials are still required to determine the selectivity index for the intracellular form of the parasite, and to develop methods to facilitate the efficient entry of the molecule into the host cell and the parasite.

OBJETIVOS: Evaluar la actividad fotodinámica in vitro de la ftalocianina de aluminio tetrasulfonada clorada (AlPcClS4) sobre promastigotes y amastigotes de Leishmania (Viannia) peruviana y Leishmania (Viannia) braziliensis. MATERIALES Y MÉTODOS: La actividad del tratamiento fotodinámico empleando AlPcClS4 sobre promastigotes y amastigotes de Leishmania fue determinada mediante el método colorimétrico Metil Tiazol Tetrazolium (MTT) y PCR cuantitativo, respectivamente. RESULTADOS: El tratamiento fotodinámico presentó un efecto inhibitorio sobre promastigotes, principalmente sobre Leishmania (V.) peruviana, en menor proporción sobre Leishmania (V.) braziliensis y sobre las formas intracelulares de ambas especies. En Leishmania (V.) peruviana, a las 24 horas posirradiación a 200 µM y 350 µM el efecto inhibitorio fue del 72,9% y 73,9%, respectivamente y a las 96 horas fue del 78,8% y 80,6%, respectivamente. En las formas intracelulares, empleando 200 µM y evaluado a las 72 horas postratamiento, se observó una inhibición del 57,8% de amastigotes de Leishmania (V.) peruviana. El IC50 fue del 56,5; 50; 44; y 39,7 µM, que corresponde a las 24, 48, 72 y 96 horas posirradiación, respectivamente. CONCLUSIONES: El tratamiento fotodinámico empleando AlPcClS4 frente a las especies de Leishmania presentó resultados alentadores principalmente sobre Leishmania (V.) peruviana, lo cual sugiere su potencial uso como alternativa o complemento del tratamiento convencional de la leishmaniasis tegumentaria. Sin embargo, aún se requiere continuar con nuevos ensayos para determinar el índice de selectividad sobre el parásito en su forma intracelular, y desarrollar estrategias que faciliten el ingreso eficiente de la molécula hacia la célula hospedera y al parásito.