Stem-like T cells are associated with the pathogenesis of ulcerative colitis in humans.

To understand the role of T cells in the pathogenesis of ulcerative colitis (UC), we analyzed colonic T cells isolated from patients with UC and controls. Here we identified colonic CD4+ and CD8+ T lymphocyte subsets with gene expression profiles resembling stem-like progenitors, previously reported in several mouse models of autoimmune disease. Stem-like T cells were increased in inflamed areas compared to non-inflamed regions from the same patients. Furthermore, TCR sequence analysis indicated stem-like T cells were clonally related to proinflammatory T cells, suggesting their involvement in sustaining effectors that drive inflammation. Using an adoptive transfer colitis model in mice, we demonstrated that CD4+ T cells deficient in either BCL-6 or TCF1, transcription factors that promote T cell stemness, had decreased colon T cells and diminished pathogenicity. Our results establish a strong association between stem-like T cell populations and UC pathogenesis, highlighting the potential of targeting this population to improve clinical outcomes.

[Plantar actinomycetoma in a patient without risk factors]. / Actinomicetoma plantar en un paciente sin factores de riesgo.

A case of plantar actinomycetoma without risk factors is presented, which was diagnosed by hystopatological analysis of a foot biopsy because of the suspicion of neoplasia. Since the patient did not fully respond to the first-line therapy antibiotics, a 24-weeks doxycycline regime was started, achieving a satisfactory response. Finally, a brief discussion on plantar mycetomas is presented.

Actinomicetoma plantar en un paciente sin factores de riesgo / Plantar actinomycetoma in a patient without risk factors

Resumen Se presenta un caso clínico de un actinomicetoma plantar en un paciente sin factores de riesgo, cuyo diagnóstico fue realizado mediante una biopsia de tejido plantar por sospecha de una neoplasia. Dado que el paciente no respondió satisfactoriamente a la terapia de primera línea, debió completar 24 semanas de tratamiento con doxiciclina, a lo cual evolucionó favorablemente. Finalmente, se desarrolla una breve discusión sobre los micetomas plantares.

A case of plantar actinomycetoma without risk factors is presented, which was diagnosed by hystopatological analysis of a foot biopsy because of the suspicion of neoplasia. Since the patient did not fully respond to the first-line therapy antibiotics, a 24-weeks doxycycline regime was started, achieving a satisfactory response. Finally, a brief discussion on plantar mycetomas is presented.

[Risk factors for preterm deliveries in a public hospital]. / Factores asociados con el parto prematuro entre 22 y 34 semanas en un hospital público de Santiago.

BACKGROUND: Preterm births are responsible for 75 to 80% of perinatal mortality. AIM: To determine the factors associated with preterm births, using maternal clinical data, laboratory results and pathological placental findings. PATIENTS AND METHODS: Retrospective study of 642 preterm single births at 22-34 weeks' gestation. Four hundred and seven cases with pathological placental studies were included. Births were subdivided into preterm births as a consequence of a medical indication and spontaneous births with or without premature rupture of membranes (PROM). Risk factors for preterm births were classified as maternal, fetal, placental, indeterminable and unclassifiable. RESULTS: The proportions of preterm births were spontaneous 69% (with PROM 27% and with intact membranes 42%) and medically indicated births 31%. A risk factor associated with prematurity was identified in 98 and 85% of medically indicated and spontaneous births, respectively. Ascending bacterial infection (ABI) was the most frequently associated factor with spontaneous preterm delivery in 51% of women (142/280, p < 0.01) and with preterm births of less than 30 weeks in 52% of women (82/157, p < 0.01). Vaginal or urinary infection with Group B Streptococcus, was the most common clinical condition associated with ABI related deliveries. Hypertension was present in 94 of 127 medically indicated preterm deliveries (preeclampsia in 62% and chronic hypertension in 12%), and in 29% (preeclampsia 24%) of preterm births of more than 30 weeks. Congenital anomalies were mainly associated with a maternal age over 35 years in 15% (14/92) of women. The frequency of placental diseases was higher in spontaneous preterm deliveries (14%) and in pregnancies of more than 30 weeks in (14%). CONCLUSIONS: ABI was the most common factor associated with spontaneous preterm births at 2234 weeks, while preeclampsia is the most common factor associated with medically indicated preterm births.

Factores asociados con el parto prematuro entre 22 y 34 semanas en un hospital público de Santiago / Risk factors for preterm deliveries in a public hospital

Background: Preterm births are responsible for 75 to 80% of perinatal mortality. Aim: To determine the factors associated with preterm births, using maternal clinical data, laboratory results and pathological placental findings. Patients and Methods: Retrospective study of 642 preterm single births at 22-34 weeks' gestation. Four hundred and seven cases with pathological placental studies were included. Births were subdivided into preterm births as a consequence of a medical indication and spontaneous births with or without premature rupture of membranes (PROM). Risk factors for preterm births were classified as maternal, fetal, placental, indeterminable and unclassifiable. Results: The proportions of preterm births were spontaneous 69% (with PROM 27% and with intact membranes 42%) and medically indicated births 31%. A risk factor associated with prematurity was identified in 98 and 85% of medically indicated and spontaneous births, respectively. Ascending bacterial infection (ABI) was the most frequently associated factor with spontaneous preterm delivery in 51% of women (142/280, p < 0.01) and with preterm births of less than 30 weeks in 52% of women (82/157, p < 0.01). Vaginal or urinary infection with Group B Streptococcus, was the most common clinical condition associated with ABI related deliveries. Hypertension was present in 94 of 127 medically indicated preterm deliveries (preeclampsia in 62% and chronic hypertension in 12%), and in 29% (preeclampsia 24%) of preterm births of more than 30 weeks. Congenital anomalies were mainly associated with a maternal age over 35 years in 15% (14/92) of women. The frequency of placental diseases was higher in spontaneous preterm deliveries (14%) and in pregnancies of more than 30 weeks in (14%). Conclusions: ABI was the most common factor associated with spontaneous preterm births at 2234 weeks, while preeclampsia is the most common factor associated with medically indicated preterm births.