Evolución clínica de trabajadores con fractura de radio distal Fernández III. Tratamiento no complicado quirúrgico y no quirúrgico.

ANTECEDENTES: Las fracturas de radio distal Fernández III (FRDF III) son una urgencia muy frecuente. Las indicaciones quirúrgicas y no quirúrgicas persisten controversiales, así como el impacto funcional. OBJETIVO: Comparar la evolución clínica de los trabajadores con FRDF III, con manejo quirúrgico frente a no quirúrgico, no complicados, en un hospital especializado. MÉTODO: Estudio comparativo, observacional y longitudinal en trabajadores con FRDF III unilateral cerrada, de ambos sexos, con evolución menor de 5 días. Se excluyeron pacientes con comorbilidad afectante de consolidación ósea y polifracturados. Se eliminaron aquellos con información incompleta, con complicaciones, con aparato de yeso modificado 5 días después de su colocación, con mala reducción-estabilización acorde a la AO. Se aplicó la Escala Funcional de Mayo para Muñeca (EFMM) a los 3 y 6 meses del tratamiento. Se utilizó la prueba t de Student. RESULTADOS: 159 pacientes, 34% mujeres, 66% hombres. Edad promedio 40.18 años. Manejo quirúrgico 42,5% (placa 8.7%, fijador 29%, fijador + clavillo 8.7%); no quirúrgico 33%. Diferencias significativas (p ≤ 0.05): EFMM 3 y 6 meses; a 3 meses: dolor, prensión; a 6 meses: movilidad; y días totales de incapacidad. CONCLUSIONES: El tratamiento quirúrgico muestra mejores resultados funcionales, destacando el dolor y la prensión a 3 meses, y la movilidad a 6 meses, con reincorporación laboral en menos tiempo. BACKGROUND: This fracture is a very frequent emergency. Surgical and non-surgical management are still controversial, such as functional impact. OBJECTIVE: To compare clinical evolution of Fernandez III distal radius fractures, managed with surgically vs no surgical treatment, in a specialized hospital. METHOD: Comparative, observational, longitudinal study, released on workers with unilateral Fernandez III closed distal radius fractures, both sex, with evolution less than 5 days. Those patients with pathologies getting difficult in bone consolidation, and with several fractures were excluded. Those with incomplete information, complicated, and whom paste were modified after 5 days, and with bad reduction or stabilization fracture according AO were eliminated. Mayo Functional Wrist Scale (EFMM) was applied at 3 and 6 months. Student-t test was applied. RESULTS: 159 patients recruited, 34% females, 66% males. Medium age 40 years old. Surgical treatment 42.5% (plaque 8.7%, external fixation 29%, external fixation and nails 8.7%). Non-surgical treatment 33%. Significative differences (p≤0.05): EFMM at 3 and 6 months; pain, grasp at 3 months; mobility at 6 months; total laboral inhability days. CONCLUSIONS: Surgical treatment shows better functional results, specially pain and grasp at 3 months, mobility at 6 months, and faster returning to work.

Geminivirus Replication Protein Impairs SUMO Conjugation of Proliferating Cellular Nuclear Antigen at Two Acceptor Sites.

Geminiviruses are DNA viruses that replicate in nuclei of infected plant cells using the plant DNA replication machinery, including PCNA (proliferating cellular nuclear antigen), a cofactor that orchestrates genome duplication and maintenance by recruiting crucial players to replication forks. These viruses encode a multifunctional protein, Rep, which is essential for viral replication, induces the accumulation of the host replication machinery, and interacts with several host proteins, including PCNA and the SUMO E2 conjugation enzyme (SCE1). Posttranslational modification of PCNA by ubiquitin or SUMO plays an essential role in the switching of PCNA between interacting partners during DNA metabolism processes (e.g., replication, recombination, and repair, etc.). In yeast, PCNA sumoylation has been associated with DNA repair involving homologous recombination (HR). Previously, we reported that ectopic Rep expression results in very specific changes in the sumoylation pattern of plant cells. In this work, we show, using a reconstituted sumoylation system in Escherichia coli, that tomato PCNA is sumoylated at two residues, K254 and K164, and that coexpression of the geminivirus protein Rep suppresses sumoylation at these lysines. Finally, we confirm that PCNA is sumoylated in planta and that Rep also interferes with PCNA sumoylation in plant cells.IMPORTANCE SUMO adducts have a key role in regulating the activity of animal and yeast PCNA on DNA repair and replication. Our work demonstrates for the first time that sumoylation of plant PCNA occurs in plant cells and that a plant virus interferes with this modification. This work marks the importance of sumoylation in allowing viral infection and replication in plants. Moreover, it constitutes a prime example of how viral proteins interfere with posttranslational modifications of selected host factors to create a proper environment for infection.

Interaction between geminivirus replication protein and the SUMO-conjugating enzyme is required for viral infection.

Geminiviruses are small DNA viruses that replicate in nuclei of infected plant cells by using plant DNA polymerases. These viruses encode a protein designated AL1, Rep, or AC1 that is essential for viral replication. AL1 is an oligomeric protein that binds to double-stranded DNA, catalyzes the cleavage and ligation of single-stranded DNA, and induces the accumulation of host replication machinery. It also interacts with several host proteins, including the cell cycle regulator retinoblastoma-related protein (RBR), the DNA replication protein PCNA (proliferating cellular nuclear antigen), and the sumoylation enzyme that conjugates SUMO to target proteins (SUMO-conjugating enzyme [SCE1]). The SCE1-binding motif was mapped by deletion to a region encompassing AL1 amino acids 85 to 114. Alanine mutagenesis of lysine residues in the binding region either reduced or eliminated the interaction with SCE1, but no defects were observed for other AL1 functions, such as oligomerization, DNA binding, DNA cleavage, and interaction with AL3 or RBR. The lysine mutations reduced or abolished virus infectivity in plants and viral DNA accumulation in transient-replication assays, suggesting that the AL1-SCE1 interaction is required for viral DNA replication. Ectopic AL1 expression did not result in broad changes in the sumoylation pattern of plant cells, but specific changes were detected, indicating that AL1 modifies the sumoylation state of selected host proteins. These results established the importance of AL1-SCE1 interactions during geminivirus infection of plants and suggested that AL1 alters the sumoylation of selected host factors to create an environment suitable for viral infection.