Polyethylene glycol fusion repair of severed rat sciatic nerves reestablishes axonal continuity and reorganizes sensory terminal fields in the spinal cord.

JOURNAL/nrgr/04.03/01300535-202507000-00030/figure1/v/2024-09-09T124005Z/r/image-tiff Peripheral nerve injuries result in the rapid degeneration of distal nerve segments and immediate loss of motor and sensory functions; behavioral recovery is typically poor. We used a plasmalemmal fusogen, polyethylene glycol (PEG), to immediately fuse closely apposed open ends of severed proximal and distal axons in rat sciatic nerves. We have previously reported that sciatic nerve axons repaired by PEG-fusion do not undergo Wallerian degeneration, and PEG-fused animals exhibit rapid (within 2-6 weeks) and extensive locomotor recovery. Furthermore, our previous report showed that PEG-fusion of severed sciatic motor axons was non-specific, i.e., spinal motoneurons in PEG-fused animals were found to project to appropriate as well as inappropriate target muscles. In this study, we examined the consequences of PEG-fusion for sensory axons of the sciatic nerve. Young adult male and female rats (Sprague-Dawley) received either a unilateral single cut or ablation injury to the sciatic nerve and subsequent repair with or without (Negative Control) the application of PEG. Compound action potentials recorded immediately after PEG-fusion repair confirmed conduction across the injury site. The success of PEG-fusion was confirmed through Sciatic Functional Index testing with PEG-fused animals showing improvement in locomotor function beginning at 35 days postoperatively. At 2-42 days postoperatively, we anterogradely labeled sensory afferents from the dorsal aspect of the hindpaw following bilateral intradermal injection of wheat germ agglutinin conjugated horseradish peroxidase. PEG-fusion repair reestablished axonal continuity. Compared to unoperated animals, labeled sensory afferents ipsilateral to the injury in PEG-fused animals were found in the appropriate area of the dorsal horn, as well as inappropriate mediolateral and rostrocaudal areas. Unexpectedly, despite having intact peripheral nerves, similar reorganizations of labeled sensory afferents were also observed contralateral to the injury and repair. This central reorganization may contribute to the improved behavioral recovery seen after PEG-fusion repair, supporting the use of this novel repair methodology over currently available treatments.

Polyethylene glycol fusion repair of severed sciatic nerves accelerates recovery of nociceptive sensory perceptions in male and female rats of different strains.

ABSTRACT: Successful polyethylene glycol fusion (PEG-fusion) of severed axons following peripheral nerve injuries for PEG-fused axons has been reported to: (1) rapidly restore electrophysiological continuity; (2) prevent distal Wallerian Degeneration and maintain their myelin sheaths; (3) promote primarily motor, voluntary behavioral recoveries as assessed by the Sciatic Functional Index; and, (4) rapidly produce correct and incorrect connections in many possible combinations that produce rapid and extensive recovery of functional peripheral nervous system/central nervous system connections and reflex (e.g., toe twitch) or voluntary behaviors. The preceding companion paper describes sensory terminal field reorganization following PEG-fusion repair of sciatic nerve transections or ablations; however, sensory behavioral recovery has not been explicitly explored following PEG-fusion repair. In the current study, we confirmed the success of PEG-fusion surgeries according to criteria (1-3) above and more extensively investigated whether PEG-fusion enhanced mechanical nociceptive recovery following sciatic transection in male and female outbred Sprague-Dawley and inbred Lewis rats. Mechanical nociceptive responses were assessed by measuring withdrawal thresholds using von Frey filaments on the dorsal and midplantar regions of the hindpaws. Dorsal von Frey filament test was a more reliable method than plantar von Frey filament test to assess mechanical nociceptive sensitivity following sciatic nerve transections. Baseline withdrawal thresholds of the sciatic-mediated lateral dorsal region differed significantly across strain but not sex. Withdrawal thresholds did not change significantly from baseline in chronic Unoperated and Sham-operated rats. Following sciatic transection, all rats exhibited severe hyposensitivity to stimuli at the lateral dorsal region of the hindpaw ipsilateral to the injury. However, PEG-fused rats exhibited significantly earlier return to baseline withdrawal thresholds than Negative Control rats. Furthermore, PEG-fused rats with significantly improved Sciatic Functional Index scores at or after 4 weeks postoperatively exhibited yet-earlier von Frey filament recovery compared with those without Sciatic Functional Index recovery, suggesting a correlation between successful pPEG-fusion and both motor-dominant and sensory-dominant behavioral recoveries. This correlation was independent of the sex or strain of the rat. Furthermore, our data showed that the acceleration of von Frey filament sensory recovery to baseline was solely due to the PEG-fused sciatic nerve and not saphenous nerve collateral outgrowths. No chronic hypersensitivity developed in any rat up to 12 weeks. All these data suggest that PEG-fusion repair of transection peripheral nerve injuries could have important clinical benefits.

Isquemia mesentérica segmentaria como secuela de la COVID-19: Informe de un caso / Segmental mesenteric ischemia as a sequel to COVID-19: A case report

Coronaviruses can cause respiratory, gastrointestinal, and central nervous system diseases in humans and animals, have the ability to adapt through mutations, and are programmed to modify host tropism. SARS-CoV-2 infection (COVID-19) has been shown to be a highly thrombogenic disease, generating deep vein thrombosis, pulmonary embolism and acute ischemia, in patients even without previous pathology. Coronaviruses can cross the species barrier and infect humans with unexpected consequences for public health. The transmission rate of SARS-CoV-2 is higher compared to that of closely related SARS-CoV infections. Key residues of the spike protein have a higher binding affinity for ACE2. These may be the reason for the higher transmission rate of SARS-CoV-2. COVID-19 has been shown in some patients to be a highly thrombogenic disease, both venous and arterial, generating deep vein thrombosis, pulmonary embolism and acute ischemia, both in patients without previous pathology as with them.There is molecular evidence of the state of hyper coagulability in COVID-19; the first observations were made by Wang, in 2020, when analyzing the levels of fibrinogen and D-dimer in patients with COVID-19 and finding elevated levels up to 75% above the laboratory controls. We present the case of a 62-year-old male with mild symptoms of COVID-19 and outpatient management, at the end of the clinical disease he presented an acute abdomen secondary to mesenteric ischemia, with good postoperative evolution.

Los coronavirus pueden causar enfermedades respiratorias, gastrointestinales y del sistema nervioso central en seres humanos y animales; tienen la capacidad para adaptarse por medio de mutaciones y son programados para modificar el tropismo del huésped. La infección por el SARS-CoV-2 (COVID-19) genera trombosis venosa profunda, embolismo pulmonar y cuadros de isquemia aguda, en pacientes sin afección previa. Los coronavirus infectan a los seres humanos con consecuencias inesperadas para la salud pública. La tasa de transmisión de la infección por el SARS-CoV-2 es más alta en comparación con las infecciones por SARS-CoV estrechamente relacionadas. Los residuos clave de la proteína espiga tienen mayor afinidad de unión por el receptor de la enzima convertidora de angiotensina (ECA2). Esta puede ser la razón de la mayor tasa de transmisión de SARS-CoV-2. La COVID-19 ha demostrado, en algunos pacientes, ser una enfermedad altamente trombogénica, tanto venosa como arterial, dado que genera trombosis venosa profunda, embolismo pulmonar y cuadros de isquemia aguda, tanto en pacientes sin afecciones previas como con ellas. Existe evidencia molecular del estado de hipercoagulabilidad en la COVID-19; las primeras observaciones fueron realizadas por Wang en 2020, al analizar los niveles de fibrinógeno y dímero-D en pacientes con COVID-19, y encontrar niveles elevados hasta 75% por arriba de los controles de laboratorio. Se presenta el caso de un paciente masculino de 62 años, con un cuadro leve de COVID-19 y abordaje ambulatorio; al término de la enfermedad clínica presentó abdomen agudo secundario a isquemia mesentérica, con buena evolución en el posoperatorio.

Influencia de los medios de comunicación y el riesgo de padecer trastornos de la conducta alimentaria en escolares mujeres en Lima, Perú / Mass media influence and risk of developing eating dis orders in female students from Lima, Peru

Introducción. Los trastornos de conducta alimentaria (TCA) son un problema de salud pública y su relación con los medios de comunicación es aún controversial. Objetivo. Evaluar si existe asociación entre los modelos de imagen corporal mostrados por los medios de comunicación y el riesgo de TCA en adolescentes escolares mujeres de Lima, Perú. Metodología. Estudio transversal realizado en tres centros educativos del distrito de La Victoria, Lima, Perú. Se midió el riesgo de TCA con la prueba de actitud alimentaria (Eating Attitudes Test-26; EAT-26, por sus siglas en inglés) y la influencia de los medios de comunicación con el cuestionario sobre actitudes socioculturales con respecto a la apariencia (Sociocultural Attitudes Towards Appearance Questionnaire-3; SATAQ-3, por sus siglas en inglés), categorizada en terciles tanto en el puntaje global como en sus subescalas (acceso a la información, presión, internalización general y atlética). Se calcularon las razones de prevalencia ajustadas (RPa) para TCA. Resultados. Se incluyeron483 escolares con edad mediana de 14 ? 3 años. El 13,9% presentó riesgo de padecer TCA. Las escolares que presentan mayor influencia de los medios de comunicación (tercil superior del SATAQ-3) tienen mayor probabilidad de tener un riesgo de TCA (RPa: 4,24; IC 95%: 2,10-8,56), así como quienes tienen mayor acceso a la información (RP: 1,89; IC 95%: 1,09-3,25), mayor presión (RP: 4,97; IC 95%: 2,3110,69), las que presentaron mayor internalización general (RP: 5,00; IC 95%: 2,39-10,43) y las que mostraron mayor grado de internalización atlética (RP: 4,35; IC 95%: 2,19-8,66). Conclusión. A mayor influencia de los medios de comunicación, existe una mayor probabilidad de riesgo de padecer TCA en escolares mujeres en Lima, Perú.

Introduction. Eating dis orders (EDs) are a public health problem, and their relationship to mass media is still controversial. Objective. To assess whether there is an association between models of body image shown in mass media and the risk of developing EDs among female adolescent students from Lima, Peru. Methodology. Cross-sectional study conducted in three schools located in the district of La Victoria, Lima, Peru. The risk of developing EDs was measured using the Eating Attitudes Test-26 (EAT-26), while mass media influence was measured using the Sociocultural Attitudes Towards Appearance Questionnaire-3 (SATAQ-3), which was categorized into tertiles both in the overall score and its subscales (information, pressure, general internalization, and athletic internalization). Adjusted prevalence ratios (aPR) for EDs were estimated. Results. Four hundred and eighty-three students were included, their median age was 14 ? 3 years old. A risk of developing an ED was observed in 13.9% of them. Students who are more influenced by mass media (upper tertile of the SATAQ-3) have a higher probability of having a risk of developingan ED (aPR: 4.24; 95% confidence interval --CI--: 2.10-8.56), as well as those who have a greater access to information (PR: 1.89; 95% CI: 1.09-3.25), suffer more pressure (PR: 4.97; 95% CI: 2.31-10.69), show a greater general internalization (PR: 5.00; 95% CI: 2.39-10.43), and show a greater level of athletic internalization (PR: 4.35; 95% CI: 2.19-8-66). Conclusion.The greater the influence of mass media, the greater the probability of having a risk of developing an ED among female students from Lima, Peru.

[Mass media influence and risk of developing eating disorders in female students from Lima, Peru]. / Influencia de los medios de comunicación y el riesgo de padecer trastornos de la conducta alimentaria en escolares mujeres en Lima, Perú.

INTRODUCTION: Eating disorders (EDs) are a public health problem, and their relationship to mass media is still controversial. OBJECTIVE: To assess whether there is an association between models of body image shown in mass media and the risk of developing EDs among female adolescent students from Lima, Peru. METHODOLOGY: Cross-sectional study conducted in three schools located in the district of La Victoria, Lima, Peru. The risk of developing EDs was measured using the Eating Attitudes Test-26 (EAT-26), while mass media influence was measured using the Sociocultural Attitudes Towards Appearance Questionnaire-3 (SATAQ-3), which was categorized into tertiles both in the overall score and its subscales (information, pressure, general internalization, and athletic internalization). Adjusted prevalence ratios (aPR) for EDs were estimated. RESULTS: Four hundred and eighty-three students were included, their median age was 14 ? 3 years old. A risk of developing an ED was observed in 13.9% of them. Students who are more influenced by mass media (upper tertile of the SATAQ-3) have a higher probability of having a risk of developing an ED (aPR: 4.24; 95% confidence interval |-CI-|: 2.10-8.56), as well as those who have a greater access to information (PR: 1.89; 95% CI: 1.09-3.25), suffer more pressure (PR: 4.97; 95% CI: 2.31-10.69), show a greater general internalization (PR: 5.00; 95% CI: 2.39-10.43), and show a greater level of athletic internalization (PR: 4.35; 95% CI: 2.19-8-66). CONCLUSION: The greater the influence of mass media, the greater the probability of having a risk of developing an ED among female students from Lima, Peru.

Introducción. Los trastornos de conducta alimentaria (TCA) son un problema de salud pública y su relación con los medios de comunicación es aún controversial. Objetivo. Evaluar si existe asociación entre los modelos de imagen corporal mostrados por los medios de comunicación y el riesgo de TCA en adolescentes escolares mujeres de Lima, Perú. Metodología. Estudio transversal realizado en tres centros educativos del distrito de La Victoria, Lima, Perú. Se midió el riesgo de TCA con la prueba de actitud alimentaria (Eating Attitudes Test-26; EAT-26, por sus siglas en inglés) y la influencia de los medios de comunicación con el cuestionario sobre actitudes socioculturales con respecto a la apariencia (Sociocultural Attitudes Towards Appearance Questionnaire-3; SATAQ-3, por sus siglas en inglés), categorizada en terciles tanto en el puntaje global como en sus subescalas (acceso a la información, presión, internalización general y atlética). Se calcularon las razones de prevalencia ajustadas (RPa) para TCA. Resultados. Se incluyeron 483 escolares con edad mediana de 14 ± 3 años. El 13,9% presentó riesgo de padecer TCA. Las escolares que presentan mayor influencia de los medios de comunicación (tercil superior del SATAQ-3) tienen mayor probabilidad de tener un riesgo de TCA (RPa: 4,24; IC 95%: 2,10-8,56), así como quienes tienen mayor acceso a la información (RP: 1,89; IC 95%: 1,09-3,25), mayor presión (RP: 4,97; IC 95%: 2,31- 10,69), las que presentaron mayor internalización general (RP: 5,00; IC 95%: 2,39-10,43) y las que mostraron mayor grado de internalización atlética (RP: 4,35; IC 95%: 2,19-8,66). Conclusión. A mayor influencia de los medios de comunicación, existe una mayor probabilidad de riesgo de padecer TCA en escolares mujeres en Lima, Perú.