Metal-Organic Frameworks for Dual Photo-Oxidation and Capture of Arsenic from Water.

Despite rapid technological progress, heavy metal water pollution, particularly arsenic contamination, remains a significant global challenge. The stabilization of trivalent arsenic as neutral arsenite (AsIII) species hinders its removal by conventional adsorption methods. While adsorption of anionic arsenate (AsV) species is in principle more feasible, there are only a few adsorbents capable of adsorbing both forms of arsenic. In this work we study the potential of two well-known families of Metal-Organic Frameworks (MOFs), UiO-66 and MIL-125, to simultaneously adsorb and photo-oxidize arsenic species from water. Our results demonstrate that the formation of AsV ions upon light irradiation promotes the subsequent adsorption of additional AsIII species. Thus, we propose the combined utilization of photocatalysis and adsorption technologies for water remediation purposes.

Biofoams with untapped enzymatic potential produced from beer bagasse by indigenous fungal strains.

White rot fungi are promising organisms for the production of mycelial-based biofoams, providing a sustainable means of valorizing lignocellulosic wastes. This study explores the utilization of two indigenous fungal species, isolated from Argentina and belonging to the genera Trametes, for producing biofoams from brewery waste. The resulting biofoams exhibited an average density of 0.30 g cm-3, a Young's modulus of approximately 1 MPa, and a compressive stress of around 19 MPa. Additionally, the variation of laccase activity throughout the biofoam production process was evaluated. Surprisingly, residual laccase activity was detected in the biofoams following oven drying at temperatures of 60, 80, and 100 °C. This detection highlights the untapped enzymatic potential of the biofoams and positions them as promising green catalysts for various biotechnological applications.

Thiol-free multicomponent synthesis of non-racemic ß-acyloxy thioethers from biocatalytically obtained chiral halohydrins.

A novel multicomponent chemoenzymatic strategy for the preparation of enantioenriched ß-acyloxy thioethers has been developed. This robust methodology employs mild bases, air atmosphere, room temperature and avoids the use of foul-smelling thiols. Instead, potassium thioacetate is employed as a universal sulfur source. This chemoselective strategy tolerates aromatic and aliphatic components and diverse functional groups. The chirality is enzymatically defined by ADH-catalyzed bioreduction of α-haloketones delivering an enantioenriched halohydrin which is one of the three components, and the optical purity remains untouched in the final product. Semipreparative scale multicomponent reaction affords high yield of the products (up to 96%).

Self-stigma in schizophrenia: a systematic review and meta-analysis of 37 studies from 25 high- and low-to-middle income countries.

In schizophrenia, it is currently thought that stigma experience is increased by psychotic and depressive symptomatology, exposure to stigma at the workplace, and that self-stigma levels vary across countries without knowing the factors explaining these variations. The aim of the present meta-analysis was to synthetize the data of observational studies comprehensively exploring multiple self-stigma dimensions and associated factors. A systematic literature search without language or time restrictions was conducted in Medline, Google Scholar, and Web of Science for studies, last 09/2021. Eligible studies that included ≥80% of patients diagnosed with schizophrenia-spectrum disorders and used a validated scale measuring self-stigma dimensions were meta-analysed using random-effects models, followed by subgroup and meta-regression analyses. Study registration: PROSPERO CRD42020185030. Overall, 37 studies (n = 7717) from 25 countries (5 continents) published between 2007 and 2020 were included, with 20 studies conducted in high-income countries. These studies used two scales with total scores ranging 1-4. The mean estimate of perceived stigma was 2.76 [95% confidence interval (CI) = 2.60-2.94], experienced stigma 2.29 [95% CI = 2.18, 2.41], alienation 2.40 [95% CI = 2.29, 2.52], stereotype endorsement 2.14 [95% CI = 2.03, 2.27], social withdrawal 2.28 [95% CI = 2.17, 2.39] and stigma resistance 2.53 [95% CI = 2.43, 2.63]). Self-stigma levels did not reduce over time. Living outside urban areas, low-income, singleness, unemployment, high antipsychotic dose and low functioning were associated with different stigma dimensions. Some stigma dimensions were lower in studies carried out in Europe compared to other regions. Most studies published since 2007 report that self-stigma is a particular concern for a specific subgroup of patients. This subgroup is characterized by unemployment, high antipsychotic dose and low functioning. We identified important other missing factors that should be explored to improve the effectiveness of public policies and personalized interventions to reduce self-stigma. Importantly, classical illness severity indices (psychotic severity, age at illness onset, illness duration) and sociodemographic variables (age, sex and education) were not associated with self-stigma, moderating previous findings.

Uso de nivolumab en pacientes con recaída postrasplante alogénico de progenitores hematopoyéticos en enfermedad de Hodgkin: reporte de dos casos clínicos / Treatment of Hodgkin disease relapse after allogeneic transplantation with nivolumab. Report of two cases

Hodgkin's Lymphoma has a very good prognosis. In the unusually refractory patients allogeneic transplantation offers a chance of cure. The so-called checkpoint inhibitors, such as Nivolumab can play a relevant role in this type of patients. Their side effects and usefulness after allogeneic transplantation are under investigation. Relapse after allogeneic transplantation has an extremely poor prognosis. We report two patients with refractory Hodgkin's lymphoma who relapsed after an allogeneic transplant and who were successfully treated with Nivolumab.

[Treatment of Hodgkin disease relapse after allogeneic transplantation with nivolumab. Report of two cases]. / Uso de nivolumab en pacientes con recaída postrasplante alogénico de progenitores hematopoyéticos en enfermedad de Hodgkin: reporte de dos casos clínicos.

Hodgkin's Lymphoma has a very good prognosis. In the unusually refractory patients allogeneic transplantation offers a chance of cure. The so-called checkpoint inhibitors, such as Nivolumab can play a relevant role in this type of patients. Their side effects and usefulness after allogeneic transplantation are under investigation. Relapse after allogeneic transplantation has an extremely poor prognosis. We report two patients with refractory Hodgkin's lymphoma who relapsed after an allogeneic transplant and who were successfully treated with Nivolumab.

[Mad pride and metaphors for dissidence: a linguistic and symbolic analysis]. / Orgullo loco y metáforas para una disidencia: un análisis lingüístico y simbólico.

This paper presents a linguistic and interpretative analysis of the use of conceptual metaphors in the field of mental health, taking as a field of observation the use of Twitter in the first edition of Mad Pride Day in Spain, held on May 20, 2018. The objective is to give a first-person account of the attitudes expressed by activists. The results show a questioning of the coercive logics produced by psychiatric care, a problematization of the hegemonic model as a whole, a criticism of the oppression implied by stigma, communication problems with professionals in the field of mental health, as well as demands for greater dialogue with them. This analysis has allowed us to understand linguistic modes of resignifying the field of mental health, and also to account for the tensions between subjective perceptions of the people diagnosed and the productions of the hegemonic medical model.

El presente artículo expone un análisis lingüístico e interpretativo sobre el uso de la metáfora conceptual en el campo de la salud mental, tomando como campo de observación el uso de Twitter en la primera edición del Día del Orgullo Loco en España, celebrada el 20 de mayo de 2018. El objetivo es dar cuenta de los posicionamientos expresados por los activistas en primera persona. Los resultados muestran un cuestionamiento a las lógicas coercitivas producidas por la atención psiquiátrica, una problematización del modelo hegemónico en su conjunto, una denuncia a la opresión que implica el estigma, problemas de comunicación y demandas de mayor diálogo con los profesionales del campo de la salud mental. Este análisis nos ha permitido comprender el modo lingüístico de re-semantizar el campo de la salud mental, así como dar cuenta de las tensiones existentes entre las percepciones subjetivas de las personas diagnosticadas y las producciones del modelo médico hegemónico.

Orgullo loco y metáforas para una disidencia: un análisis lingüístico y simbólico / Mad pride and metaphors for dissidence: a linguistic and symbolic analysis

RESUMEN El presente artículo expone un análisis lingüístico e interpretativo sobre el uso de la metáfora conceptual en el campo de la salud mental, tomando como campo de observación el uso de Twitter en la primera edición del Día del Orgullo Loco en España, celebrada el 20 de mayo de 2018. El objetivo es dar cuenta de los posicionamientos expresados por los activistas en primera persona. Los resultados muestran un cuestionamiento a las lógicas coercitivas producidas por la atención psiquiátrica, una problematización del modelo hegemónico en su conjunto, una denuncia a la opresión que implica el estigma, problemas de comunicación y demandas de mayor diálogo con los profesionales del campo de la salud mental. Este análisis nos ha permitido comprender el modo lingüístico de re-semantizar el campo de la salud mental, así como dar cuenta de las tensiones existentes entre las percepciones subjetivas de las personas diagnosticadas y las producciones del modelo médico hegemónico.

ABSTRACT This paper presents a linguistic and interpretative analysis of the use of conceptual metaphors in the field of mental health, taking as a field of observation the use of Twitter in the first edition of Mad Pride Day in Spain, held on May 20, 2018. The objective is to give a first-person account of the attitudes expressed by activists. The results show a questioning of the coercive logics produced by psychiatric care, a problematization of the hegemonic model as a whole, a criticism of the oppression implied by stigma, communication problems with professionals in the field of mental health, as well as demands for greater dialogue with them. This analysis has allowed us to understand linguistic modes of resignifying the field of mental health, and also to account for the tensions between subjective perceptions of the people diagnosed and the productions of the hegemonic medical model.

Thiol-free chemoenzymatic synthesis of ß-ketosulfides.

A preparation of ß-ketosulfides avoiding the use of thiols is described. The combination of a multicomponent reaction and a lipase-catalysed hydrolysis has been developed in order to obtain high chemical diversity employing a single sulfur donor. This methodology for the selective synthesis of a set of ß-ketosulfides is performed under mild conditions and can be set up in one-pot two-step and on a gram-scale.

Eritrodermia psoriática en un hombre joven: sospechar infección por VIH / Erythrodermic psoriasis in young man: suspect HIV infection

Resumen La infección por VIH puede presentarse con distintas manifestaciones cutáneas, que en algunas ocasiones son consideradas marcadores de infección. Una posible manifestación es la eritrodermia psoriática, que corresponde a una forma generalizada de psoriasis. Presentamos un caso clínico de un hombre joven en que se sospechó una infección por VIH por un cuadro de eritrodermia psoriática confirmada por biopsia, asociado a un sarcoma de Kaposi. Posteriormente, la infección por VIH fue confirmada por serología. Se manejó con terapia antirretroviral, con buena respuesta al mes de tratamiento. La eritrodermia psoriática se puede considerar un marcador cutáneo de infección por VIH cuando ocurre en pacientes previamente sanos o con psoriasis recalcitrante.

HIV infection can be manifested with different skin symptoms, which are sometimes considered infection markers. Erythrodermic psoriasis is a possible manifestation, which is a widespread form of psoriasis. We report a clinical case of a young man suspected of HIV infection due to a psoriatic erythroderma confirmed by biopsies, associated with Kaposi sarcoma. Afterwards, HIV infection was confirmed by serological tests. Antiretroviral therapy was started, with positive response at one month of treatment. Erythrodermic psoriasis can be considered a skin marker of HIV infection when occurs in previously healthy patients or in recalcitrant psoriasis.

Tenogenically Induced Allogeneic Peripheral Blood Mesenchymal Stem Cells in Allogeneic Platelet-Rich Plasma: 2-Year Follow-up after Tendon or Ligament Treatment in Horses.

Poor healing of tendon and ligament lesions often results in early retirement of sport horses. Therefore, regenerative therapies are being explored as potentially promising treatment for these injuries. In this study, an intralesional injection was performed with allogeneic tenogenically induced mesenchymal stem cells and platelet-rich plasma 5-6 days after diagnosis of suspensory ligament (SL) (n = 68) or superficial digital flexor tendon (SDFT) (n = 36) lesion. Clinical, lameness and ultrasonographic evaluation was performed at 6 and 12 weeks. Moreover, a survey was performed 12 and 24 months after treatment to determine how many horses were competing at original level and how many were re-injured. At 6 weeks, 88.2% of SL (n = 68) and 97.3% of SDFT lesions (n = 36) demonstrated moderate ultrasonographic improvement. At 12 weeks, 93.1% of SL (n = 29) and 95.5% of SDFT lesions (n = 22) improved convincingly. Moreover, lameness was abolished in 78.6% of SL (n = 28) and 85.7% (n = 7) of SDFT horses at 12 weeks. After 12 months (n = 92), 11.8% of SL and 12.5% of SDFT horses were re-injured, whereas 83.8 of SL and 79.2% of SDFT returned to previous performance level. At 24 months (n = 89) after treatment, 82.4 (SL) and 85.7% (SDFT) of the horses returned to previous level of performance. A meta-analysis was performed on relevant published evidence evaluating re-injury 24 months after stem cell-based [17.6% of the SL and 14.3% of the SDFT group (n = 89)] versus conventional therapies. Cell therapies resulted in a significantly lower re-injury rate of 18% [95% confidence interval (CI), 0.11-0.25] 2 years after treatment compared to the 44% re-injury rate with conventional treatments (95% CI, 0.37-0.51) based on literature data (P < 0.0001).

[Erythrodermic psoriasis in young man: suspect HIV infection]. / Eritrodermia psoriática en un hombre joven: sospechar infección por VIH.

HIV infection can be manifested with different skin symptoms, which are sometimes considered infection markers. Erythrodermic psoriasis is a possible manifestation, which is a widespread form of psoriasis. We report a clinical case of a young man suspected of HIV infection due to a psoriatic erythroderma confirmed by biopsies, associated with Kaposi sarcoma. Afterwards, HIV infection was confirmed by serological tests. Antiretroviral therapy was started, with positive response at one month of treatment. Erythrodermic psoriasis can be considered a skin marker of HIV infection when occurs in previously healthy patients or in recalcitrant psoriasis.

Tuberculides tuberculosas en población adulta de la Región Metropolitana, Chile: serie de casos 2006-2010 / Tuberculids in the adult population of the Region Metropolitan, Chile: case series 2006-2010

Introducción: Las tuberculides tuberculosas (TLTB) se subdividen en verdaderas de etiología atribuible al Mycobacterium tuberculosis y facultativas causadas por múltiples condiciones, entre ellas la tuberculosis. En Chile representan el 75% de las tuberculosis cutáneas en la región metropolitana (RM). Objetivo: caracterizar las TLTB de la RM de acuerdo a epidemiología, clínica, estudio y manejo terapéutico. Material y método: Estudio descriptivo retrospectivo del total de TLTB diagnosticadas por biopsia en los servicios de anatomía patológica de 4 hospitales públicos de la RM y un hospital privado de la RM en el quinquenio 2006-2010. Resultados: 83 casos de TLTB, 59% aportados por el sistema público, 84% de los pacientes fueron mujeres, 18% fueron tuberculides verdaderas y 82% tuberculides facultativas. A pesar de ser el tratamiento antituberculoso la elección en las tuberculides verdaderas, sólo se indicó en el 65% de los casos y de estos, 45% realmente lo realizó. Sólo el 4,5% de las tuberculides facultativas de esta serie tuvieron indicación de tratamiento antituberculoso, realizándose en el 100% de los casos. Conclusión: Existe seguimiento insuficiente a través del tiempo en estos pacientes, dificultando dimensionar el éxito real de los tratamientos indicados. Se evidencia una falla en la coordinación al momento de derivar los pacientes al programa de control de la tuberculosis.

Introduction: Tuberculids are subdivided in true tuberculids, which are associated to mycobacterium tuberculosis, and facultative tuberculids which can be caused by several conditions, including tuberculosis. In Chile tuberculids represent 75% of cutaneous tuberculosis in the metropolitan region (MR). Objective: to characterize tuberculids according to epidemiology, clinical, study and therapeutic management. Methods: Descriptive study of the total tuberculids diagnosed by biopsy in the pathology services of 4 public hospitals of the MRI and a private hospital of the MRI in the five-year period 2006- 2010. Results: 83 cases of tuberculids, 59% where provided by the public system, 84% of the patients were women, 18% were true tuberculids and 82% facultative tuberculids. Despite being antitubercular therapy the first line treatment for true tuberculids, this treatment was prescribed in 65% of cases and only 45% of these were actually treated. Only 4.5% of the facultative tuberculids in this series had indication of antitubercular therapy, performed in 100% of cases. Conclusions: There is insufficient follow up in these patients, making it difficult to assess the real success of the treatment. Is evident the lack of coordination when referring patients to the tuberculosis control program.

Embolización de los miomas uterinos por vía transradial / Uterine fibroid embolization using the transradial approach

Objetivo: determinar la seguridad y la eficacia de la embolización uterina por vía transradial en el tratamiento de las pacientes con miomas sintomáticos. Diseño del estudio: estudio prospectivo realizado en una institución terciaria. 64 pacientes con miomas sintomáticos fueron tratadas mediante embolización por vía transradial. Se realizaron controles previos, al mes y al semestre del procedimiento. Resultados: se completó la embolización de las dos arterias uterinas en 62 pacientes (97%), con una duración media del procedimiento de 87,5 ± 39, 1 minutos. No hubo ninguna complicación local en el acceso vascular. Respecto a la eficacia, se demostró un aumento medio de la hemoglobina desde 10,95 g/dL antes del tratamiento hasta 12,56 g/dL, después del mismo. Igualmente, se produjo una mejoría de la calidad de vida de las pacientes, con un descenso significativo de la puntuación al semestre de la embolización (85,84 ± 29,27 previa, 27,00 ± 22,45 a los 6 meses). Se produjo reingreso precoz en el 14% de las pacientes, por dolor y finalmente se operaron 3 pacientes (4,69%) por no haber mejorado de sus síntomas Conclusión: la embolización uterina transradial es segura y tan efectiva para el tratamiento de los miomas como la transfemoral (AU)

Objective: To determine the safety and efficacy of uterine fibroid embolisation using the transradial approach. Study design: This prospective study was conducted at a tertiary institution. Sixty-four patients with symptomatic uterine fibroids underwent fibroid embolisation using the transradial approach. The patients were assessed before the procedure and 1 and 6 months after the procedure. Results: Embolisation via both uterine arteries was achieved in 62 of the 64 patients (97%), with a mean procedure time of 87.5 ± 39.1 min. Objective assessment showed an increase in the haemoglobin concentration from 10.95 g/dL before the procedure to 12.56 g/dL after 6 months, and a 42% decrease in the volume of the largest fibroid after 6 months. Subjective assessment showed a significant improvement in the quality of life score from 85.84 ± 29.27 before the procedure to 27.00 ± 22.45 after 6 months. There were no vascular complications related to the transradial access. Early readmission was required in 14% of patients due to pain. Three patients (4.69%) underwent subsequent hysterectomy because their symptoms did not improve after the embolisation procedure. Conclusion: Uterine fibroid embolisation using the transradial approach is safe and is as effective as using the transfemoral approach (AU)

Clinical Research Office of the Endourological Society Global GreenLight Laser Study: Outcomes from a contemporary series of 713 patients.

OBJECTIVE: To evaluate the outcome in patients undergoing photoselective vaporization of the prostate for benign prostatic obstruction as part of the Clinical Research Office of the Endourological Society Global GreenLight Laser Study. METHODS: Data were collected on 713 patients with lower urinary tract symptoms suggestive of benign prostatic obstruction undergoing photoselective vaporization of the prostate at 25 centers worldwide, between April 2010 and April 2012. Three types of GreenLight laser powers were used: 80 W, 120 W or 180 W. Intraoperative and postoperative complications were recorded. Outcome parameters measured at baseline, 6-12 weeks, 6 months and 12 months were: uroflow measurements, International Prostate Symptom Score; prostate-specific antigen and International Index of Erectile Function. RESULTS: Operating time was shortest with the 180-W laser at 53.8 min. Intraoperatively, bleeding occurred in 3.1% of patients. Statistically significant changes were reported in maximum flow rate, postvoid residual urine, International Prostate Symptom Score, quality of life score and prostate-specific antigen (P < 0.01) at each time-point assessed for the 80- and 120-W lasers as well as for the 180-W laser, with the exception of prostate-specific antigen at 6 months and 12 months. There were 14 Clavien-Dindo grade III-A complications and two grade III-B. The incontinence rate at 12 months was 6.3%, 4.5%, and 2.6% for the 80, 120 and 180 W lasers, respectively. The overall blood transfusion rate was 0.4%. CONCLUSIONS: Objective and subjective improvement after GreenLight laser treatment worldwide was significant at 1-year follow up. Morbidity and complications were low. Although not a randomized control study, the data can provide an indication of the outcome of the different GreenLight laser powers.

Scintigraphic tracking of mesenchymal stem cells after intravenous regional limb perfusion and subcutaneous administration in the standing horse.

OBJECTIVE: To assess distribution, uptake, and persistence of radiolabeled mesenchymal stem cells (MSC) using scintigraphy after intravenous regional limb perfusion (RLP) and subcutaneous injections in standing, sedated horses. STUDY DESIGN: Experimental study. ANIMALS: Horses (n = 12). METHODS: Six horses had RLP performed through the cephalic vein on 1 limb and subcutaneous injection in the metacarpal area in the opposite limb. The other 6 horses had RLP performed through the lateral palmar digital vein and subcutaneous injection in the coronary band. A pneumatic tourniquet was used for the RLP. MSC were labeled with technetium-HMPAO. Scintigraphic images were obtained at the time of injection, 1, 6, and 24 hours later. Results of RLP were compared with results from previous studies where similar injections were performed in anesthetized horses. RESULTS: Both RLP techniques led to greater variability, lower uptake, lower persistence, and poorer distribution when compared to results previously reported for horses under general anesthesia. The subcutaneous injections in the metacarpal area and coronary band resulted in MSC loss to the general circulation but no evidence of local migration. CONCLUSION: Due to partial or complete failure of the tourniquet, RLP performed in the standing horse as described is less efficient than performed under general anesthesia. Further work is needed to optimize the use of tourniquets to perform RLP for MSC administration in standing patients. The subcutaneous injections did not result in local migration in these normal horses.

Evaluation of a diode laser for use in induction of tendinopathy in the superficial digital flexor tendon of horses.

OBJECTIVE: To evaluate use of a diode laser to induce tendinopathy in the superficial digital flexor tendon (SDFT) of horses. ANIMALS: 4 equine cadavers and 5 adult horses. PROCEDURES: Cadaveric SDFT samples were exposed to a diode laser at various energy settings to determine an appropriate energy for use in in vivo experiments; lesion size was assessed histologically. In vivo experiments involved laser energy induction of lesions in the SDFT (2 preliminary horses [0, 25, 75, and 87.5 J] and 3 study horses [0 and 125 J]) and assessment of lesions. Study duration was 21 days, and lesions were assessed clinically and via ultrasonography, MRI, and histologic evaluation. RESULTS: Lesion induction in cadaveric tissues resulted in a spherical cavitated core with surrounding tissue coagulation. Lesion size had a linear relationship (R2 = 0.9) with the energy administered. Size of in vivo lesions in preliminary horses indicated that larger lesions were required. In study horses, lesions induced with 125 J were ultrasonographically and histologically larger than were control lesions. At proximal and distal locations, pooled (preliminary and study horses) ultrasonographically assessed lesions were discrete and variable in size (mean ± SEM lesion percentage for control lesions, 8.5 ± 3%; for laser lesions, 12.2 ± 1.7%). Ultrasonography and MRI measurements were associated (R2 > 0.84) with cross-sectional area measurements. CONCLUSIONS AND CLINICAL RELEVANCE: In vivo diode laser-induced lesions did not reflect cadaveric lesions in repeatable size. Further research is required before diode lasers can reliably be used for inducing tendinopathy.

The effect of growth factors on both collagen synthesis and tensile strength of engineered human ligaments.

Growth factors play a central role in the development and remodelling of musculoskeletal tissues. To determine which growth factors optimized in vitro ligament formation and mechanics, a Box-Behnken designed array of varying concentrations of growth factors and ascorbic acid were applied to engineered ligaments and the collagen content and mechanics of the grafts were determined. Increasing the amount of transforming growth factor (TGF) ß1 and insulin-like growth factor (IGF)-1 led to an additive effect on ligament collagen and maximal tensile load (MTL). In contrast, epidermal growth factor (EGF) had a negative effect on both collagen content and MTL. The predicted optimal growth media (50 µg/ml TGFß, IGF-1, and GDF-7 and 200 µM ascorbic acid) was then validated in two separate trials: showing a 5.7-fold greater MTL and 5.2-fold more collagen than a minimal media. Notably, the effect of the maximized growth media was scalable such that larger constructs developed the same material properties, but larger MTL. These results show that optimizing the interactions between growth factors and engineered ligament volume results in an engineered ligament of clinically relevant function.

Magic angle magnetic resonance imaging of diode laser induced and naturally occurring lesions in equine tendons.

Magic angle magnetic resonance (MR) imaging consists of imaging tendons at 55° to the magnetic field. In people, magic angle MR imaging is valuable for detection of chronic tendon lesions and allows calculation of tendon T1 values. Increased T1 values occur in people with chronic tendinopathy. The T1 values of normal equine tendons have been reported but there are no available data for abnormal equine tendons. Twelve limbs were studied. Two limbs had diode laser tendon lesions induced postmortem, four limbs had diode laser tendon lesions induced in vivo and six limbs had naturally occurring tendon lesions. The limbs were imaged at 1.5 T using both conventional MR imaging and magic angle MR imaging. The post-mortem laser induced lesions were identified only with magic angle MR imaging. The in vivo induced lesions and naturally occurring lesions were identified with both techniques but had a different appearance with the two imaging techniques. Magic angle imaging was helpful at identifying lesions that were hypointense on conventional imaging. Increased T1 values were observed in all abnormal tendons and in several tendons with a subjectively normal MR appearance. The increased T1 value may reflect diffuse changes in the biochemical composition of tendons. Magic angle imaging has potential as a useful noninvasive tool to assess the changes of the extracellular tendon matrix using T1 values.

Evaluation of senescence in mesenchymal stem cells isolated from equine bone marrow, adipose tissue, and umbilical cord tissue.

Mesenchymal stem cells (MSCs) from adult and neonatal tissues are intensively investigated for their use in regenerative medicine. The purpose of this study was to compare the onset of replicative senescence in MSCs isolated from equine bone marrow (BMSC), adipose tissue (ASC), and umbilical cord tissue (UCMSC). MSC proliferation (cell doubling), senescence-associated ß-galactosidase staining, telomere length, Sox-2, and lineage-specific marker expression were assessed for MSCs harvested from tissues of 4 different donors. The results show that before senescence ensued, all cell types proliferated at ∼1 day/cell doubling. BMSCs significantly increased population doubling rate by passage 10 and ceased proliferation after a little >30 total population doublings, whereas UCMSCs and ASCs achieved about 60 to 80 total population doublings. UCMSC and ASCs showed marked ß-galactosidase staining after ∼70 population doublings, whereas BMSCs stained positive by ∼30 population doublings. The onset of senescence was associated with a significant reduction in telomere length averaging 10.2 kbp at passage 3 and 4.5 kbp in senescent cultures. MSCs stained intensively for osteonectin at senescence compared with earlier passages, whereas vimentin and low levels of smooth muscle actin were consistently expressed. Sox-2 gene expression was consistently noted in all 3 MSC types. In conclusion, equine BMSCs appear to senesce much earlier than ASCs and UCMSCs. These results demonstrate the limited passage numbers of subcultured BMSCs available for use in research and tissue engineering and suggest that adipose tissue and umbilical cord tissue may be preferable for tissue banking purposes.