An evo-devo view of the gynoecium.

The appearance of the flower marks a key event in the evolutionary history of plants. Among the four types of floral organs, the gynoecium represents the major adaptive advantage of the flower. The gynoecium is an enclosing structure that protects and facilitates the fertilization of the ovules, which then mature as seeds. Upon fertilization, in many species, the gynoecium itself eventually becomes the fruit, which contributes to the dispersal of the seeds. However, despite its importance and the recent advances in our understanding of the genetic regulatory network guiding early gynoecium development, many questions remain to be resolved regarding the extent of the conservation of the molecular mechanisms for gynoecium development among different taxa, and how these mechanisms give origin and diversification to the gynoecium. In this review, we compile the existing knowledge about the evolution, development, and molecular mechanisms involved in the origin and evolution of the gynoecium.

Twisting development, the birth of a potential new gene.

Evolution has long been considered to be a conservative process in which new genes arise from pre-existing genes through gene duplication, domain shuffling, horizontal transfer, overprinting, retrotransposition, etc. However, this view is changing as new genes originating from non-genic sequences are discovered in different organisms. Still, rather limited functional information is available. Here, we have identified TWISTED1 (TWT1), a possible de novo-originated protein-coding gene that modifies microtubule arrangement and causes helicoidal growth in Arabidopsis thaliana when its expression is increased. Interestingly, even though TWT1 is a likely recent gene, the lack of TWT1 function affects A. thaliana development. TWT1 seems to have originated from a non-genic sequence. If so, it would be one of the few examples to date of how during evolution de novo genes are integrated into developmental cellular and organismal processes.

Patrones clínicos y neurofisiológicos de presentación temprana en la polirradiculoneuropatía inflamatoria desmielinizante crónica de inicio agudo / Clinical and neurophysiological patterns of early presenting symptoms in acute onset chronic inflammatory demyelinating polyradiculoneuropathy

Introducción: Dentro de los fenotipos de polineuropatía desmielinizante inflamatoria crónica (CIDP) existe uno cuyo tiempo de evolución es menor de ocho semanas desde el inicio de los síntomas, denominado de inicio agudo (A-CIDP). Esta entidad puede confundirse con el síndrome de Guillain-Barré, variedad desmielinizante inflamatoria aguda (AIDP), lo que retrasa el inicio del tratamiento. Objetivo: Analizar las diferencias clínicas y electrofisiológicas entre A-CIDP, CIDP clásica y AIDP, con el fin de identificar factores que auxilien al diagnóstico diferencial de forma temprana. Pacientes y métodos: Se realizó un estudio transversal con pacientes atendidos en la clínica de enfermedades neuromusculares del Instituto Nacional de Neurología y Neurocirugía con diagnóstico de CIDP según criterios de la European Federation of Neurological Societies and Peripheral Nerve Society. Los pacientes con CIDP <8 semanas se catalogaron como A-CIDP y fueron comparados con pacientes diagnosticados con CIDP clásica y AIDP. Se obtuvieron y analizaron variables clínicas, paraclínicas y electrofisiológicas. Resultados: Se observaron diferencias significativas en antecedente de infección, afección de nervios del cráneo y disautonomías entre la A-CIDP y la AIDP. Los registros electrofisiológicos describieron diferencias significativas en velocidad de conducción de los nervios motores y en los registros del nervio sural, que fueron menores en el grupo de A-CIDP. Conclusión: El antecedente de infección, la afección de nervios del cráneo y las disautonomías son parámetros importantes que se debe tener en cuenta para el diagnóstico diferencial de estas entidades. El análisis electrofisiológico es similar entre la A-CIDP y la CIDP. El diagnóstico diferencial entre estos tipos de polineuropatía desmielinizante debe basarse en el juicio clínico.(AU)

Introduction: The phenotypes of chronic inflammatory demyelinating polyneuropathy (CIDP) include an acute-onset phenotype (A-CIDP) with an evolution time of less than eight weeks from the onset of symptoms. This entity can be confused with Guillain-Barré syndrome of the acute inflammatory demyelinating variety (AIDP), delaying the start of treatment. Objective: To analyze the clinical and electrophysiological differences between A-CIDP, classic CIDP and AIDP, in order to identify factors that may help in the early differential diagnosis. Patients and methods: A cross-sectional study was carried out with patients seen at the neuromuscular disease clinic of the National Institute of Neurology and Neurosurgery with a diagnosis of CIDP according to the criteria of the European Federation of Neurological Societies and Peripheral Nerve Society. Patients with CIDP <8 weeks were categorized as A-CIDP and were compared with patients diagnosed with classic CIDP and AIDP. Clinical, paraclinical and electrophysiological variables were obtained and analyzed. Results: Significant differences in history of infection, cranial nerve involvement and dysautonomia were observed between A-CIDP and AIDP. Electrophysiological recordings reported significant differences in motor nerve conduction velocity and sural nerve recordings, being lower in the A-CIDP group. Conclusion: A history of infection, cranial nerve involvement and dysautonomia are important parameters to take into account for the differential diagnosis of these entities. Electrophysiological analysis is similar between A-CIDP and CIDP. The differential diagnosis between these types of demyelinating polyneuropathy must be based on clinical assessment.(AU)

[Clinical and neurophysiological patterns of early presenting symptoms in acute onset chronic inflammatory demyelinating polyradiculoneuropathy]. / Patrones clínicos y neurofisiológicos de presentación temprana en la polirradiculoneuropatía inflamatoria desmielinizante crónica de inicio agudo.

INTRODUCTION: The phenotypes of chronic inflammatory demyelinating polyneuropathy (CIDP) include an acute-onset phenotype (A-CIDP) with an evolution time of less than eight weeks from the onset of symptoms. This entity can be confused with Guillain-Barre syndrome of the acute inflammatory demyelinating variety (AIDP), delaying the start of treatment. OBJECTIVE: To analyze the clinical and electrophysiological differences between A-CIDP, classic CIDP and AIDP, in order to identify factors that may help in the early differential diagnosis. PATIENTS AND METHODS: A cross-sectional study was carried out with patients seen at the neuromuscular disease clinic of the National Institute of Neurology and Neurosurgery with a diagnosis of CIDP according to the criteria of the European Federation of Neurological Societies and Peripheral Nerve Society. Patients with CIDP <8 weeks were categorized as A-CIDP and were compared with patients diagnosed with classic CIDP and AIDP. Clinical, paraclinical and electrophysiological variables were obtained and analyzed. RESULTS: Significant differences in history of infection, cranial nerve involvement and dysautonomia were observed between A-CIDP and AIDP. Electrophysiological recordings reported significant differences in motor nerve conduction velocity and sural nerve recordings, being lower in the A-CIDP group. CONCLUSION: A history of infection, cranial nerve involvement and dysautonomia are important parameters to take into account for the differential diagnosis of these entities. Electrophysiological analysis is similar between A-CIDP and CIDP. The differential diagnosis between these types of demyelinating polyneuropathy must be based on clinical assessment.

TITLE: Patrones clínicos y neurofisiológicos de presentación temprana en la polirradiculoneuropatía inflamatoria desmielinizante crónica de inicio agudo.Introducción. Dentro de los fenotipos de polineuropatía desmielinizante inflamatoria crónica (CIDP) existe uno cuyo tiempo de evolución es menor de ocho semanas desde el inicio de los síntomas, denominado de inicio agudo (A-CIDP). Esta entidad puede confundirse con el síndrome de Guillain-Barré, variedad desmielinizante inflamatoria aguda (AIDP), lo que retrasa el inicio del tratamiento. Objetivo. Analizar las diferencias clínicas y electrofisiológicas entre A-CIDP, CIDP clásica y AIDP, con el fin de identificar factores que auxilien al diagnóstico diferencial de forma temprana. Pacientes y métodos. Se realizó un estudio transversal con pacientes atendidos en la clínica de enfermedades neuromusculares del Instituto Nacional de Neurología y Neurocirugía con diagnóstico de CIDP según criterios de la European Federation of Neurological Societies and Peripheral Nerve Society. Los pacientes con CIDP inferior a 8 semanas se catalogaron como A-CIDP y fueron comparados con pacientes diagnosticados con CIDP clásica y AIDP. Se obtuvieron y analizaron variables clínicas, paraclínicas y electrofisiológicas. Resultados. Se observaron diferencias significativas en antecedente de infección, afección de nervios del cráneo y disautonomías entre la A-CIDP y la AIDP. Los registros electrofisiológicos describieron diferencias significativas en velocidad de conducción de los nervios motores y en los registros del nervio sural, que fueron menores en el grupo de A-CIDP. Conclusión. El antecedente de infección, la afección de nervios del cráneo y las disautonomías son parámetros importantes que se debe tener en cuenta para el diagnóstico diferencial de estas entidades. El análisis electrofisiológico es similar entre la A-CIDP y la CIDP. El diagnóstico diferencial entre estos tipos de polineuropatía desmielinizante debe basarse en el juicio clínico.

Guillain-Barre syndrome in Mexico: clinical features and validation of Brighton Collaboration Group criteria. / Síndrome de Guillain-Barré en México: características clínicas y validación de los criterios de Brighton.

INTRODUCTION: As SARS-CoV-2 vaccination is ongoing in Mexico and Guillain-Barre syndrome (GBS) cases have been reported, validation of Brighton criteria in Mexico is necessary. Moreover, epidemiology of GBS in Mexico differs from European and North American countries. OBJECTIVE: To describe the clinical, cerebrospinal and electrodiagnostic features in Mexican patients diagnosed with GBS and classify them according to the Brighton Collaboration Group diagnostic criteria. Patrients and methods. An ambispective cohort study was conducted. We included patients that fulfilled the National Institute of Neurological Disorders and Stroke (NINDS) diagnostic criteria for Guillain-Barre syndrome. Patients in this study were classified according to Brighton collaboration group levels of certainty for Guillain-Barre syndrome. RESULTS: Sixty eight percent of patients were male. Of the 248 patients included, 58.4% had history of a precedent infection, mean time from symptom onset to admission was 5 (1-30) days. Mean Medical Research Council sum score 30.3 ± 15.5. Almost 98% of patients had a monophasic course. Level 1 of certainty according to Brighton collaboration group criteria was fulfilled by 54.6% of patients, level 2 by 45% and level 4 by 0.6%. Patients meeting level 2 of certainty were mostly because normal cerebrospinal fluid findings or findings in nerve conduction studies not consistent with any GBS variants. CONCLUSION: GBS is a frequent autoimmune neuropathy that has been associated with preceding infections and with vaccination campaigns. For SARS-CoV-2 vaccination campaign in Mexico, validation of Brighton Criteria is necessary. Although Mexico's GBS epidemiology has been changing throughout recent years, this study provides similar data compared to other countries.

TITLE: Síndrome de Guillain-Barré en México: características clínicas y validación de los criterios de Brighton.Introducción. Dado que la vacunación contra el SARS-CoV-2 está en curso en México y se han notificado casos de Guillain-Barré, es necesaria la validación de los criterios de Brighton en México. La epidemiología de Guillain-Barré en México difiere de la de los países europeos y norteamericanos. Objetivo. Describir las características clínicas, cerebroespinales y electrodiagnósticas en pacientes mexicanos con diagnóstico de Guillain-Barré y clasificarlos según los criterios diagnósticos del Brighton Collaboration Group. Pacientes y métodos. Se realizó un estudio de cohorte ambispectivo. Se incluyó a pacientes que cumplen con los criterios del National Institute of Neurological Disorders and Stroke para el síndrome de Guillain-Barré (SGB). Se clasificó a los pacientes según los niveles de certeza del Brighton Collaboration Group para el SGB. Resultados. El 68% de los pacientes eran hombres. De los 248 pacientes incluidos, el 58,4% tenía antecedentes de infección previa. La media desde el inicio de los síntomas hasta el ingreso fue de 5 (1-30) días, y la puntuación media de la suma del Medical Research Council, de 30,3 ± 15,5. El nivel 1 de certeza según los criterios del Brighton Collaboration Group se cumplió en el 54,6% de los pacientes; el nivel 2, en el 45%; y el nivel 4, en el 0,6%. Los pacientes que alcanzaron el nivel 2 de certeza se debieron principalmente a hallazgos normales en el líquido cefalorraquídeo o a hallazgos en estudios de neuroconducción que no cumplen los criterios de ninguna variante de SGB. Conclusión. El SGB es una neuropatía autoinmune frecuente que se ha asociado con infecciones previas y con campañas de vacunación. Para la campaña de vacunación contra el SARS-CoV-2 en México es necesaria la validación de los criterios de Brighton. Aunque la epidemiología del SGB en México ha ido cambiando a lo largo de los últimos años, este estudio proporciona datos similares en comparación con otros países.

Síndrome de Guillain-Barré en México: características clínicas y validación de los criterios de Brighton / Guillain-Barré syndrome in Mexico: clinical features and validation of Brighton Collaboration Group criteria

Introducción: Dado que la vacunación contra el SARS-CoV-2 está en curso en México y se han notificado casos de Guillain-Barré, es necesaria la validación de los criterios de Brighton en México. La epidemiología de Guillain-Barré en México difiere de la de los países europeos y norteamericanos. Objetivo: Describir las características clínicas, cerebroespinales y electrodiagnósticas en pacientes mexicanos con diagnóstico de Guillain-Barré y clasificarlos según los criterios diagnósticos del Brighton Collaboration Group. Pacientes y métodos: Se realizó un estudio de cohorte ambispectivo. Se incluyó a pacientes que cumplen con los criterios del National Institute of Neurological Disorders and Stroke para el síndrome de Guillain-Barré (SGB). Se clasificó a los pacientes según los niveles de certeza del Brighton Collaboration Group para el SGB. Resultados: El 68% de los pacientes eran hombres. De los 248 pacientes incluidos, el 58,4% tenía antecedentes de infección previa. La media desde el inicio de los síntomas hasta el ingreso fue de 5 (1-30) días, y la puntuación media de la suma del Medical Research Council, de 30,3 ± 15,5. El nivel 1 de certeza según los criterios del Brighton Collaboration Group se cumplió en el 54,6% de los pacientes; el nivel 2, en el 45%; y el nivel 4, en el 0,6%. Los pacientes que alcanzaron el nivel 2 de certeza se debieron principalmente a hallazgos normales en el líquido cefalorraquídeo o a hallazgos en estudios de neuroconducción que no cumplen los criterios de ninguna variante de SGB. Conclusión: El SGB es una neuropatía autoinmune frecuente que se ha asociado con infecciones previas y con campañas de vacunación. Para la campaña de vacunación contra el SARS-CoV-2 en México es necesaria la validación de los criterios de Brighton. Aunque la epidemiología del SGB en México ha ido cambiando a lo largo de los últimos años, este estudio proporciona datos similares en comparación con otros países.(AU)

Introduction: As SARS-CoV-2 vaccination is ongoing in Mexico and Guillain-Barré syndrome (GBS) cases have been reported, validation of Brighton criteria in Mexico is necessary. Moreover, epidemiology of GBS in Mexico differs from European and North American countries. Objective: To describe the clinical, cerebrospinal and electrodiagnostic features in Mexican patients diagnosed with GBS and classify them according to the Brighton Collaboration Group diagnostic criteria. Patrients and methods: An ambispective cohort study was conducted. We included patients that fulfilled the National Institute of Neurological Disorders and Stroke (NINDS) diagnostic criteria for Guillain-Barré syndrome. Patients in this study were classified according to Brighton collaboration group levels of certainty for Guillain-Barré syndrome. Results: Sixty eight percent of patients were male. Of the 248 patients included, 58.4% had history of a precedent infection, mean time from symptom onset to admission was 5 (1-30) days. Mean Medical Research Council sum score 30.3 ± 15.5. Almost 98% of patients had a monophasic course. Level 1 of certainty according to Brighton collaboration group criteria was fulfilled by 54.6% of patients, level 2 by 45% and level 4 by 0.6%. Patients meeting level 2 of certainty were mostly because normal cerebrospinal fluid findings or findings in nerve conduction studies not consistent with any GBS variants. Conclusion: GBS is a frequent autoimmune neuropathy that has been associated with preceding infections and with vaccination campaigns. For SARS-CoV-2 vaccination campaign in Mexico, validation of Brighton Criteria is necessary. Although Mexico’s GBS epidemiology has been changing throughout recent years, this study provides similar data compared to other countries.(AU)

Síndrome de Guillain-Barré durante la pandemia de COVID-19: experiencia de un centro de referencia en México / Guillain-Barré syndrome during COVID-19 pandemic: experience from a referral healthcare center in Mexico

Introducción: Se trata de describir las características clínicas y variantes electrofisiológicas de los casos de síndrome de Guillain-Barré (SGB) durante la pandemia. Llevamos a cabo un análisis comparativo entre pacientes con SGB relacionado con el SARS-CoV-2 y sin antecedente del virus, y posteriormente realizamos una comparación con los casos de 2019. Pacientes y métodos: Se llevó a cabo un estudio transversal de los pacientes con diagnóstico de SGB según los criterios de Asbury y Cornblath. Se recolectaron información clínica y variables paraclínicas. Definimos el SGB relacionado con el SARS-CoV-2 conforme a la descripción de Ellul et al. Se utilizaron los criterios de Hadden para la clasificación de las variantes electrofisiológicas. Por último, realizamos un análisis comparativo entre grupos. Resultados: Se diagnosticó a 42 pacientes con SGB en 2020, un 64,2% hombres, con una edad de 46 ± 17,4 años, un 42,8% con obesidad/sobrepeso, un 31% con historia de diarrea previa y un 14,2% con infección respiratoria previa. El 71,4% tuvo una puntuación en la Guillain-Barré Disability Score igual o mayor que 3 puntos y el 69% tenía afectados los nervios del cráneo. La variante electrofisiológica más común fue la polirradiculoneuropatía desmielinizante inflamatoria aguda (PDIA; 53,5%). Siete (16,6%) casos tuvieron relación con el SARS-CoV-2, cuatro hombres, con edad de 43,4 ± 13,4 años. Al realizar la comparación entre pacientes con SGB de 2020 frente a los de 2019, observamos un decremento en el antecedente de infección previa en 2020 (45,2 frente a 73,3%; p = 0,005) y un decremento específico en la historia de infección respiratoria (14,2 frente a 33,3%; p = 0,045), así como una mayor frecuencia de afectación de los nervios del cráneo y de disociación albuminocitológica. Conclusiones: Las maniobras preventivas para la infección por el SARS-CoV-2 impactan directamente en la presentación de enfermedades postinfecciosas como el SGB...(AU)

Introduction: To describe clinical characteristics and electrophysiological variants of GBS cases during the pandemic, we carried out a comparative analysis between SARS-CoV2 related GBS and non-SARS-CoV2 patients and then compared to the 2019 cases. Patients and methods: We carried out a cross-sectional study of GBS patients diagnosed according to Asbury and Cornblath criteria. We collected information on clinical and paraclinical variables. We defined a SARS-CoV-2 related GBS case according to the description of Ellul et al. We used Hadden criteria to classify the electrophysiological variants. We performed a comparative analysis between groups. Results: Fourty-two patients were diagnosed with GBS in 2020, men 64.2%, age 46 ± 17.4 years, patients with obesity/overweight 42.8%, previous diarrhea 31%, history of respiratory tract infection 14.2%. Guillain Barre Disability Scale ≥ 3 points 71.4% and, cranial nerve involvement 69%. The most frequent electrophysiological variant was acute inflammatory demyelinating polyradiculoneuropathy (AIDP) 53.5%. Seven (16.6%) cases were SARS-CoV2 related, four men, age 43.4 ± 13.4 years. When comparing patients with GBS in 2020 vs patients in 2019, we observed a decrease in the previous infection history during 2020 (45.2% vs 73.3%, p-value = 0.005) and a decrease in previous respiratory infection (14.2% vs 33.3%, p = 0.045), as well as a higher frequency of cranial nerve involvement, and albuminocytologic dissociation. Conclusions: SARS-CoV2 virus infection preventive measures may be impacting the presentation of post-infectious diseases such as GBS. We did not observe an increase in GBS cases during 2020. Also, the AIDP variant were more frequent in our population in the COVID-19 pandemic.(AU)

Efficacy of long-term prednisone therapy in patients with chronic inflammatory demyelinating polyneuropathy (CIDP): a retrospective cohort study. / Eficacia del uso de prednisona como terapia a largo plazo en pacientes con polineuropatía desmielinizante inflamatoria crónica (PDIC): una cohorte retrospectiva.

INTRODUCTION: Patients with CIDP respond adequately to steroid therapy and intravenous immunoglobulin (IVIG). However, few patients have access to IVIG in developing countries. Little information exists about the clinical response to steroid therapy in Latin American countries. OBJECTIVE: to describe the long-term functional clinical response (24 months) to prednisone therapy in CIDP patients. MATERIAL AND METHODS: A retrospective cohort was conducted. Selection included patients with definitive CIDP diagnosis according to European criteria from the Neuromuscular Diseases clinic of the National Institute of Neurology and Neurosurgery between January 2016 and December 2020. Good response to steroid therapy was defined as with improvement in at least one point on the GBS disability score. Poor response to steroid therapy was defined as patients who did not show improvement in at least one point on the GBS disability score. Patients were evaluated at 3, 6, 12, 18 and 24 months. RESULTS: Forty-seven patients with CIDP were included. Half of them were male and mean age was 46±15 years. Mean time since symptom onset to diagnosis was 6 (IQR 2-12) months. The most common clinical variant was sensory-motor 57.4%, followed by acute-onset CIDP 21.3% and atypical variants 21.2%. At diagnosis our patients presented: mean GBS disability score of 3 (2.25-4) points, MRC score 39.5 ± 12 points, independent gait in 17%, mean prednisone dose of 50 mg (32.5-50). Twenty-four months after prednisone therapy, a less mean GBS disability score -1(0-2) points-, mean MRC score 56.3 ± 5.1 points, independent gait 93% and prednisone dose 1 (0-5) mg. Patients with poor three-month functional clinical response had a delay in diagnosis > 6 months (64.7% vs 27.5%) and atypical clinical variants (47% vs 6.8%). CONCLUSION: CIDP patients treated with prednisone have good long-term functional clinical response. Delay in diagnosis and atypical variant are common clinical characteristics for poor functional clinical response in treatment with prednisone.

TITLE: Eficacia del uso de prednisona como terapia a largo plazo en pacientes con polineuropatía desmielinizante inflamatoria crónica (PDIC): una cohorte retrospectiva.Introducción. Los pacientes con polineuropatía desmielinizante inflamatoria crónica (PDIC) responden adecuadamente a la terapia con esteroides y a la inmunoglobulina intravenosa (IgIV). Sin embargo, pocos pacientes tienen acceso a la IgIV en los países en desarrollo. Existe poca información sobre la respuesta clínica a la terapia con esteroides en los países de Latinoamérica. Objetivo. Describir la respuesta clínica funcional a largo plazo (24 meses) a la terapia con prednisona en pacientes con PDIC. Material y métodos. Se realizó una cohorte retrospectiva. La selección incluyó a pacientes con diagnóstico definitivo de PDIC según los criterios europeos de la Clínica de Enfermedades Neuromusculares del Instituto Nacional de Neurología y Neurocirugía entre enero de 2016 y diciembre de 2020. La buena respuesta a la terapia con esteroides se definió como una mejoría al menos en un punto de la Guillain-Barre Disability Score (GBS). La mala respuesta a la terapia con esteroides se definió como pacientes que no mostraron mejoría al menos en un punto en la GBS. Los pacientes fueron evaluados a los 3, 6, 12, 18 y 24 meses. Resultados. Se incluyó a 47 pacientes con PDIC. La mitad de ellos eran varones y la edad media fue de 46 ± 15 años. El tiempo medio desde el inicio de los síntomas hasta el diagnóstico fue de 6 (rango intercuartílico: 2-12) meses. La variante clínica más común fue la sensomotora (57,4%), seguida de la PDIC de inicio agudo (21,3%) y de variantes atípicas (21,2%). En el momento del diagnóstico, nuestros pacientes presentaban: GBS media de 3 (2,25-4) puntos, puntuación de la escala del Medical Research Council (MRC) de 39,5 ± 12 puntos, marcha independiente en el 17% y dosis media de prednisona de 50 mg (32,5-50). Veinticuatro meses después de la terapia con prednisona, la GBS media era menor ­1 (0-2) puntos­, la puntuación media del MRC era de 56,3 ± 5,1 puntos, había marcha independiente en el 93% y la dosis de prednisona era de 1 mg (0-5). Los pacientes con mala respuesta clínica funcional a los tres meses tuvieron un retraso en el diagnóstico > 6 meses (64,7% frente a 27,5%) y variantes clínicas atípicas (47% frente a 6,8%). Conclusión. Los pacientes con PDIC tratados con prednisona tienen una buena respuesta clínica funcional a largo plazo. El retraso en el diagnóstico y la variante atípica son características clínicas frecuentes de la respuesta clínica funcional deficiente en el tratamiento con prednisona.

Guillain-Barre syndrome during COVID-19 pandemic: experience from a referral healthcare center in Mexico. / Síndrome de Guillain-Barré durante la pandemia de COVID-19: experiencia de un centro de referencia en México.

INTRODUCTION: To describe clinical characteristics and electrophysiological variants of GBS cases during the pandemic, we carried out a comparative analysis between SARS-CoV2 related GBS and non-SARS-CoV2 patients and then compared to the 2019 cases. PATIENTS AND METHODS: We carried out a cross-sectional study of GBS patients diagnosed according to Asbury and Cornblath criteria. We collected information on clinical and paraclinical variables. We defined a SARS-CoV-2 related GBS case according to the description of Ellul et al. We used Hadden criteria to classify the electrophysiological variants. We performed a comparative analysis between groups. RESULTS: Fourty-two patients were diagnosed with GBS in 2020, men 64.2%, age 46 ± 17.4 years, patients with obesity/overweight 42.8%, previous diarrhea 31%, history of respiratory tract infection 14.2%. Guillain Barre Disability Scale = 3 points 71.4% and, cranial nerve involvement 69%. The most frequent electrophysiological variant was acute inflammatory demyelinating polyradiculoneuropathy (AIDP) 53.5%. Seven (16.6%) cases were SARS-CoV2 related, four men, age 43.4 ± 13.4 years. When comparing patients with GBS in 2020 vs patients in 2019, we observed a decrease in the previous infection history during 2020 (45.2% vs 73.3%, p-value = 0.005) and a decrease in previous respiratory infection (14.2% vs 33.3%, p = 0.045), as well as a higher frequency of cranial nerve involvement, and albuminocytologic dissociation. CONCLUSIONS: SARS-CoV2 virus infection preventive measures may be impacting the presentation of post-infectious diseases such as GBS. We did not observe an increase in GBS cases during 2020. Also, the AIDP variant were more frequent in our population in the COVID-19 pandemic.

TITLE: Síndrome de Guillain-Barré durante la pandemia de COVID-19: experiencia de un centro de referencia en México.Introducción. Se trata de describir las características clínicas y variantes electrofisiológicas de los casos de síndrome de Guillain-Barré (SGB) durante la pandemia. Llevamos a cabo un análisis comparativo entre pacientes con SGB relacionado con el SARS-CoV-2 y sin antecedente del virus, y posteriormente realizamos una comparación con los casos de 2019. Pacientes y métodos. Se llevó a cabo un estudio transversal de los pacientes con diagnóstico de SGB según los criterios de Asbury y Cornblath. Se recolectaron información clínica y variables paraclínicas. Definimos el SGB relacionado con el SARS-CoV-2 conforme a la descripción de Ellul et al. Se utilizaron los criterios de Hadden para la clasificación de las variantes electrofisiológicas. Por último, realizamos un análisis comparativo entre grupos. Resultados. Se diagnosticó a 42 pacientes con SGB en 2020, un 64,2% hombres, con una edad de 46 ± 17,4 años, un 42,8% con obesidad/sobrepeso, un 31% con historia de diarrea previa y un 14,2% con infección respiratoria previa. El 71,4% tuvo una puntuación en la Guillain-Barré Disability Score igual o mayor que 3 puntos y el 69% tenía afectados los nervios del cráneo. La variante electrofisiológica más común fue la polirradiculoneuropatía desmielinizante inflamatoria aguda (PDIA; 53,5%). Siete (16,6%) casos tuvieron relación con el SARS-CoV-2, cuatro hombres, con edad de 43,4 ± 13,4 años. Al realizar la comparación entre pacientes con SGB de 2020 frente a los de 2019, observamos un decremento en el antecedente de infección previa en 2020 (45,2 frente a 73,3%; p = 0,005) y un decremento específico en la historia de infección respiratoria (14,2 frente a 33,3%; p = 0,045), así como una mayor frecuencia de afectación de los nervios del cráneo y de disociación albuminocitológica. Conclusiones. Las maniobras preventivas para la infección por el SARS-CoV-2 impactan directamente en la presentación de enfermedades postinfecciosas como el SGB. No observamos un incremento en los casos de SGB durante 2020. Asimismo, la variante de PDIA fue la más frecuente en nuestra población durante la pandemia de COVID-19.

Eficacia del uso de prednisona como terapia a largo plazo en pacientes con polineuropatía desmielinizante inflamatoria crónica (PDIC): una cohorte retrospectiva / Efficacy of long-term prednisone therapy in patients with chronic inflammatory demyelinating polyneuropathy (CIDP): a retrospective cohort study

Introducción: Los pacientes con polineuropatía desmielinizante inflamatoria crónica (PDIC) responden adecuadamente a la terapia con esteroides y a la inmunoglobulina intravenosa (IgIV). Sin embargo, pocos pacientes tienen acceso a la IgIV en los países en desarrollo. Existe poca información sobre la respuesta clínica a la terapia con esteroides en los países de Latinoamérica. Objetivo: Describir la respuesta clínica funcional a largo plazo (24 meses) a la terapia con prednisona en pacientes con PDIC. Material y métodos. Se realizó una cohorte retrospectiva. La selección incluyó a pacientes con diagnóstico definitivo de PDIC según los criterios europeos de la Clínica de Enfermedades Neuromusculares del Instituto Nacional de Neurología y Neurocirugía entre enero de 2016 y diciembre de 2020. La buena respuesta a la terapia con esteroides se definió como una mejoría al menos en un punto de la Guillain-Barre Disability Score (GBS). La mala respuesta a la terapia con esteroides se definió como pacientes que no mostraron mejoría al menos en un punto en la GBS. Los pacientes fueron evaluados a los 3, 6, 12, 18 y 24 meses. Resultados: Se incluyó a 47 pacientes con PDIC. La mitad de ellos eran varones y la edad media fue de 46 ± 15 años. El tiempo medio desde el inicio de los síntomas hasta el diagnóstico fue de 6 (rango intercuartílico: 2-12) meses. La variante clínica más común fue la sensomotora (57,4%), seguida de la PDIC de inicio agudo (21,3%) y de variantes atípicas (21,2%). En el momento del diagnóstico, nuestros pacientes presentaban: GBS media de 3 (2,25-4) puntos, puntuación de la escala del Medical Research Council (MRC) de 39,5 ± 12 puntos, marcha independiente en el 17% y dosis media de prednisona de 50 mg (32,5-50). Veinticuatro meses después de la terapia con prednisona, la GBS media era menor –1 (0-2) puntos–, la puntuación media del MRC era de 56,3 ± 5,1 puntos, había marcha independiente en el 93% y la dosis de prednisona era de 1 mg (0-5)...(AU)

Introduction: Patients with CIDP respond adequately to steroid therapy and intravenous immunoglobulin (IVIG). However, few patients have access to IVIG in developing countries. Little information exists about the clinical response to steroid therapy in Latin American countries. Objective: to describe the long-term functional clinical response (24 months) to prednisone therapy in CIDP patients. Material and methods. A retrospective cohort was conducted. Selection included patients with definitive CIDP diagnosis according to European criteria from the Neuromuscular Diseases clinic of the National Institute of Neurology and Neurosurgery between January 2016 and December 2020. Good response to steroid therapy was defined as with improvement in at least one point on the GBS disability score. Poor response to steroid therapy was defined as patients who did not show improvement in at least one point on the GBS disability score. Patients were evaluated at 3, 6, 12, 18 and 24 months. Results: Forty-seven patients with CIDP were included. Half of them were male and mean age was 46±15 years. Mean time since symptom onset to diagnosis was 6 (IQR 2-12) months. The most common clinical variant was sensory-motor 57.4%, followed by acute-onset CIDP 21.3% and atypical variants 21.2%. At diagnosis our patients presented: mean GBS disability score of 3 (2.25-4) points, MRC score 39.5 ± 12 points, independent gait in 17%, mean prednisone dose of 50 mg (32.5-50). Twenty-four months after prednisone therapy, a less mean GBS disability score –1(0-2) points–, mean MRC score 56.3 ± 5.1 points, independent gait 93% and prednisone dose 1 (0-5) mg. Patients with poor three-month functional clinical response had a delay in diagnosis > 6 months (64.7% vs 27.5%) and atypical clinical variants (47% vs 6.8%)...(AU)

Redundant and Non-redundant Functions of the AHK Cytokinin Receptors During Gynoecium Development.

The phytohormone cytokinin is crucial for plant growth and development. The site of action of cytokinin in the plant is dependent on the expression of the cytokinin receptors. In Arabidopsis, there are three cytokinin receptors that present some overlap in expression pattern. Functional studies demonstrated that the receptors play highly redundant roles but also have specialized functions. Here, we focus on gynoecium development, which is the female reproductive part of the plant. Cytokinin signaling has been demonstrated to be important for reproductive development, positively affecting seed yield and fruit production. Most of these developmental processes are regulated by cytokinin during early gynoecium development. While some information is available, there is a gap in knowledge on cytokinin function and especially on the cytokinin receptors during early gynoecium development. Therefore, we studied the expression patterns and the role of the cytokinin receptors during gynoecium development. We found that the three receptors are expressed in the gynoecium and that they have redundant and specialized functions.

Cytotoxic Lesions of the Corpus Callosum Caused by Thermogenic Dietary Supplements.

Consumption of over-the-counter dietary supplements to reduce body weight is common among the population. Thermogenics are herbal combinations that claim to produce a fat-burning process through an increase in the cellular metabolic rate and greater cellular energy consumption, having a high risk for patients developing toxic leukoencephalopathy. We present a series of 6 patients with acute neurologic symptoms and MR imaging showing restricted diffusion and decreased apparent diffusion coefficient values (mean value, 400 mm2/s × 10-6) in the entire corpus callosum compatible with a cytotoxic lesion of the corpus callosum. Although patients responded favorably to the product discontinuation with rapid recovery of neurologic symptoms, there was a more prolonged resolution on imaging alterations. Because of the widespread availability and unregulated nature of thermogenic dietary supplements, physicians must be aware of the clinical and radiologic characteristics of these potential complications of their use.

Control of stem cell activity in the carpel margin meristem (CMM) in Arabidopsis.

KEY MESSAGE: Overview of the current understanding of the molecular mechanisms that regulate meristem activity in the CMM compared to the SAM. Meristems are undifferentiated cells responsible for post-embryonic plant development. The meristems are able to form new organs continuously by carefully balancing between stem cell proliferation and cell differentiation. The plant stem cell niche in each meristem harbors the stem cells that are important to maintain each meristem. The shoot apical meristem (SAM) produces all above-parts of a plant and the molecular mechanisms active in the SAM are actively studied since many years, and models are available. During the reproductive phase of the plant, the inflorescence meristem gives rise to floral meristems, which give rise to the flowers. During floral development, the gynoecium forms that contains a new meristem inside, called the carpel margin meristem (CMM). In Arabidopsis, the gynoecium consists out of two fused carpels, where the CMM forms along the fused carpel margins. In this review, we focus on the molecular mechanisms taking place in the CMM, and we discuss similarities and differences found in the SAM.

The AP2/ERF Transcription Factor DRNL Modulates Gynoecium Development and Affects Its Response to Cytokinin.

The gynoecium is the female reproductive system in flowering plants. It is a complex structure formed by different tissues, some that are essential for reproduction and others that facilitate the fertilization process and nurture and protect the developing seeds. The coordinated development of these different tissues during the formation of the gynoecium is important for reproductive success. Both hormones and genetic regulators guide the development of the different tissues. Auxin and cytokinin in particular have been found to play important roles in this process. On the other hand, the AP2/ERF2 transcription factor BOL/DRNL/ESR2/SOB is expressed at very early stages of aerial organ formation and has been proposed to be a marker for organ founder cells. In this work, we found that this gene is also expressed at later stages during gynoecium development, particularly at the lateral regions (the region related to the valves of the ovary). The loss of DRNL function affects gynoecium development. Some of the mutant phenotypes present similarities to those observed in plants treated with exogenous cytokinins, and AHP6 has been previously proposed to be a target of DRNL. Therefore, we explored the response of drnl-2 developing gynoecia to cytokinins, and found that the loss of DRNL function affects the response of the gynoecium to exogenously applied cytokinins in a developmental-stage-dependent manner. In summary, this gene participates during gynoecium development, possibly through the dynamic modulation of cytokinin homeostasis and response.

Synergistic relationship between auxin and cytokinin in the ovary and the participation of the transcription factor SPATULA.

The phytohormones auxin and cytokinin are key regulators of plant development, and both regulate almost all aspects of plant growth and development. Communication between auxin-cytokinin signaling pathways has been the subject of intense research. However, few studies have focused specifically on the development of the early gynoecium. We have recently discovered that cytokinin signaling plays a role in the regulation of auxin biosynthesis and transport in the ovary region of the gynoecium, and that the transcription factor SPATULA (SPT) is necessary. Here, we provide evidence that indicates that cytokinin and auxin have a synergistic relationship at the medial domain during gynoecium development, and that SPT is important for this interaction.

The bHLH transcription factor SPATULA enables cytokinin signaling, and both activate auxin biosynthesis and transport genes at the medial domain of the gynoecium.

Fruits and seeds are the major food source on earth. Both derive from the gynoecium and, therefore, it is crucial to understand the mechanisms that guide the development of this organ of angiosperm species. In Arabidopsis, the gynoecium is composed of two congenitally fused carpels, where two domains: medial and lateral, can be distinguished. The medial domain includes the carpel margin meristem (CMM) that is key for the production of the internal tissues involved in fertilization, such as septum, ovules, and transmitting tract. Interestingly, the medial domain shows a high cytokinin signaling output, in contrast to the lateral domain, where it is hardly detected. While it is known that cytokinin provides meristematic properties, understanding on the mechanisms that underlie the cytokinin signaling pattern in the young gynoecium is lacking. Moreover, in other tissues, the cytokinin pathway is often connected to the auxin pathway, but we also lack knowledge about these connections in the young gynoecium. Our results reveal that cytokinin signaling, that can provide meristematic properties required for CMM activity and growth, is enabled by the transcription factor SPATULA (SPT) in the medial domain. Meanwhile, cytokinin signaling is confined to the medial domain by the cytokinin response repressor ARABIDOPSIS HISTIDINE PHOSPHOTRANSFERASE 6 (AHP6), and perhaps by ARR16 (a type-A ARR) as well, both present in the lateral domains (presumptive valves) of the developing gynoecia. Moreover, SPT and cytokinin, probably together, promote the expression of the auxin biosynthetic gene TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (TAA1) and the gene encoding the auxin efflux transporter PIN-FORMED 3 (PIN3), likely creating auxin drainage important for gynoecium growth. This study provides novel insights in the spatiotemporal determination of the cytokinin signaling pattern and its connection to the auxin pathway in the young gynoecium.

Imaging early stages of the female reproductive structure of Arabidopsis by confocal laser scanning microscopy.

BACKGROUND: The gynoecium is the female reproductive structure and probably the most complex plant structure. During its development, different internal tissues and structures are formed. Insights in gene expression or hormone localization patterns are key to understanding gynoecium development from a molecular biology point of view. RESULTS: Imaging with a confocal laser scanning microscope (CLSM) is a widely used strategy; however, visualization of internal developmental expression patterns in the Arabidopsis gynoecium can be technically challenging. Here, we present a detailed protocol that allows the visualization of internal expression patterns at high resolution during gynoecium development. We demonstrate the applicability using a cytokinin response marker (TCS::GFP), an auxin response marker (DR5::VENUS), and a SEPALLATA3 marker (SEP3::SEP3:GFP). CONCLUSIONS: The detailed protocol presented here allows the visualization of fluorescence signals in internal structures during Arabidopsis gynoecium development. This protocol may also be adapted for imaging other challenging plant structures or organs.

Cytokinin treatments affect the apical-basal patterning of the Arabidopsis gynoecium and resemble the effects of polar auxin transport inhibition.

The apical-basal axis of the Arabidopsis gynoecium is established early during development and is divided into four elements from the bottom to the top: the gynophore, the ovary, the style, and the stigma. Currently, it is proposed that the hormone auxin plays a critical role in the correct apical-basal patterning through a concentration gradient from the apical to the basal part of the gynoecium, as chemical inhibition of polar auxin transport through 1-N-naphtylphtalamic acid (NPA) application, severely affects the apical-basal patterning of the gynoecium. In this work, we show that the apical-basal patterning of gynoecia is also sensitive to exogenous cytokinin (benzyl amino purine, BAP) application in a similar way as to NPA. BAP and NPA treatments were performed in different mutant backgrounds where either cytokinin perception or auxin transport and perception were affected. We observed that cytokinin and auxin signaling mutants are hypersensitive to NPA treatment, and auxin transport and signaling mutants are hypersensitive to BAP treatment. BAP effects in apical-basal gynoecium patterning are very similar to the effects of NPA, therefore, it is possible that BAP affects auxin transport in the gynoecium. Indeed, not only the cytokinin-response TCS::GFP marker, but also the auxin efflux carrier PIN1 (PIN1::PIN1:GFP) were both affected in BAP-induced valveless gynoecia, suggesting that the BAP treatment producing the morphological changes has an impact on both in the response pattern to cytokinin and on auxin transport. In summary, we show that cytokinin affects proper apical-basal gynoecium patterning in Arabidopsis in a similar way to the inhibition of polar auxin transport, and that auxin and cytokinin mutants and markers suggest a relation between both hormones in this process.