Correction: Intestinal epithelial cell-specific RARα depletion results in aberrant epithelial cell homeostasis and underdeveloped immune system.

The original version of this Article omitted the author Margarita Parada-kusz from the Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, MA, USA.

Intestinal epithelial cell-specific RARα depletion results in aberrant epithelial cell homeostasis and underdeveloped immune system.

Retinoic acid (RA), a dietary vitamin A metabolite, is crucial in maintaining intestinal homeostasis. RA acts on intestinal leukocytes to modulate their lineage commitment and function. Although the role of RA has been characterized in immune cells, whether intestinal epithelial cells (IECs) rely on RA signaling to exert their immune-regulatory function has not been examined. Here we demonstrate that lack of RA receptor α (RARα) signaling in IECs results in deregulated epithelial lineage specification, leading to increased numbers of goblet cells and Paneth cells. Mechanistically, lack of RARα resulted in increased KLF4+ goblet cell precursors in the distal bowel, whereas RA treatment inhibited klf4 expression and goblet cell differentiation in zebrafish. These changes in secretory cells are associated with increased Reg3g, reduced luminal bacterial detection, and an underdeveloped intestinal immune system, as evidenced by an almost complete absence of lymphoid follicles and gut resident mononuclear phagocytes. This underdeveloped intestinal immune system shows a decreased ability to clear infection with Citrobacter rodentium. Collectively, our findings indicate that epithelial cell-intrinsic RARα signaling is critical to the global development of the intestinal immune system.

Retinoic acid takes effector T cells to the gallows: P2X7, the molecular hangman.

Effector T-cell contraction is one of the primary means by which immune homeostasis in the peripheral tissues is reestablished following an inflammatory response. In this issue of Mucosal Immunology, Hashimoto-Hill et al.1 show that retinoic acid (RA) transcriptionally upregulates P2X7 primarily in effector T cells of the intestine sensitizing them to NAD-induced cell death (NICD); thus, demonstrating a previously unrecognized role of RA in effector T-cell contraction.

[Prospective, randomized, comparative study of the efficacy, safety and cost of cefuroxime versus cephradine in acute pyelonephritis during pregnancy]. / Estudio prospectivo, randomizado, comparativo de la eficacia, seguridad y costos de cefuroxima vs cefradina en la pielonefritis aguda del embarazo.

BACKGROUND: Second generation cephalosporins (CFPs) are more active in the treatment of acute pyelonephritis during pregnancy but their cost is considerably higher than their predecessors. Cefuroxime, a second generation CFP with oral and parenteral presentations, might offer significant advantages and become a first choice antimicrobial in this setting. AIM: To compare the efficacy, safety and cost of cefuroxime and cephradine in the treatment of acute pyelonephritis in pregnancy. PATIENTS AND METHODS: Hospitalized women with 12 to 34 weeks of pregnancy, with clinical and bacteriological diagnosis of acute pyelonephritis, were randomly assigned to receive cefuroxime (Curocef(r), Glaxo Wellcome) 750 mg t.i.d, i.v. or cephradine 1 g q.i.d., i.v. If the isolated organism was resistant to the assigned drug the patient was excluded. Once patients were afebrile, they were switched to an oral form of the same antimicrobial. They were discharged according to the clinical status and treated for a total of 14 days. laboratory tests, including urine culture were requested during controls and at the end of follow-up at 28 days. RESULTS: One hundred and one patients were randomized: 49 to receive cephradine and 52 to receive cefuroxime. Patients in the cefuroxime group hed fewer febrile days (mean 1.7 vs 2.2, p < 0.05), faster clinical recovery (mean 2.7 vs 3.1 days, p < 0.05), a higher rate of bacteriological cure at 28 days (78.8% and 59.2%, p < 0.05) and lower rate of failure (21.2% vs 40.8% p < 0.05). The rate of resistance of isolated uropathogens was 14% to cephradine and 1% to cefuroxime. CONCLUSIONS: Cefuroxime can be considered as a first choice option in the treatment of acute pyelonephritis during pregnancy due to its tolerance, microbiological activity and efficacy.

[Pregnancy and the use of pacemakers]. / Emarazo y uso de marcapaso.

We present a 19 year old patient with complete atrioventricular block, who had a permanent demand type pacemaker-implanted. Her pregnancy and labor were uneventful. There were no maternal nor neonatal complications. Since the association of pregnancy and pacemaker use is rare, we present our experience and management of the case.

[A molar pregnancy coexistent with a viable fetus in a twin pregnancy]. / Gestación molar coexistente con feto viable en una gestación gemelar.

A case of molar gestation associated with an only fetus, both product of an twin gestation is presenting. We analyzed the clinical picture, the diagnostic method, the after birth resolution and evolution of this gestation. The result of a live newborn of 1,300 g and verify coexisting of complete hydatidiform mole.

[Acute respiratory failure in pregnancy, labor and the puerperium]. / Falla respiratoria aguda en el embarazo, parto y puerperio.

Two clinical cases of acute respiratory failure during post-partum are presented. Clinical diagnostic, procedures and lab methods are emphasized. The rise of this pathology in the pregnant woman is pointed out.

[Pelvic inflammations]. / Inflamaciones pelvianas.

PIP: Pelvic inflammations account for approximately 1/4 of the economic resources expended for maternity care in Chile. The use of IUDs has replaced abortion as the primary cause of pelvic inflammation. Sexually transmitted diseases are increasing but have not yet become a major cause of pelvic inflammations. A retrospective study was conducted of women hospitalized for pelvic inflammations in the septic unit of a hospital in Santiago, Chile, in 1980-83. Among the 313 women admitted with a diagnosis of pelvic inflammation, ages ranged from 17 to 57 and averaged 30.4 years. 11.1% were nulligestes, 25.2% were primiparas, 55.5% were multiparas, and 7.9% were grand multiparas. 45 of the 313 reported an induced abortion prior to the pelvic complication. 126 women (40.2%) reported use of an IUD. 36 women had postpartum infections, and no risk factor was identified for the remainder. The major clinical symptoms were abdominal pain in 67.7%, fever in 48.5%, metrorrhagia in 14.0%, and palpable mass on gynecological examination in 52.3%. Sonography was performed in 92 cases and laparoscopy in 20. Use of laparoscopy increased greatly after the study period and has proven to be extremely valuable in diagnosis. 121 of the 313 patients were treated medically and 192 were treated medically and surgically. The average hospital stay was 8.8 days, with a maximum of 80 days and a minimum of 1 day. The admission diagnosis was incorrect in 138 cases and correct in 175. A purulent acute appendicitis was discovered in 1 patient with a presumed tubo-ovarian abscess. The mortality rate was 1.2%.^ieng

Embarazo gemelar y malformacion de uno de los fetos. / Twin pregnancy and malofrmation of one fo the fetus

1. Se presentan dos casos de pacientes con embarazos gemelar y un feto malformado, cuyo diagnostico fue planteado por el estudio ecografico. 2. Se refiere la evolucion de ambas gestaciones, los estudios de laboratorio realizados y el diagnostico histopatologico de las placentas, mortinato y de ambos mortineonatos. Se obtuvo sobrevida de un recien nacido. 3. Hacemos especial referencia a la utilidad e importancia de la ultrasonografia en el diagnostico y seguimiento del embarazo multiple. 4. Planteamos las dificultades que enfrenta el obstetra, al saber que existe un feto malformado y uno aparentemente sano y lo dificil que es predecir el curso que seguira el embarazo, por la frecuente asociacion con patologias que tienen a provocar parto prematuro

[Ectopic Lippes' intrauterine devices. Hysterography]. / Dispositivos intrauterinos de Lippes ectópicos. Estudio histerográfico.

PIP: Statistics on the indicence of ectopia (displacement) of Lippes loop vary significantly by author; from .5/1000 to 6.81/1000 insertions. It is not clear whether ectopia occurs as a result of uterine perforation or of progressive migration. In all reported cases, however, hysterography was used to investigate. 50 patients from a control group of 1064 active Lippes D users chosen from the Family Planning Center of the San Camilo Hospital in San Felipe were studied between 1965-1969. Observations were made using x-ray and hysterography at 10 days, 1 month, 3 months, 6 months, and 1 year or more after insertion. Also studied were some of the characteristics of the loop and techniques for its insertion. In the 50 patients the device was found to be out of place in 6 (an ectopia rate of 5.6/1000 insertions), in a normal position in 30, and in an abnormal one in 14 (the distal part near or across the neck). All the ectopia was observed in patients between 20-34 years who had had 2-5 births. Those with 7-13 births did not seem to be prone to the complication. 8 of the 50 had a retroflexed uterus and 2 of those were displacement cases, suggesting that anomaly of position could be a predisposition for ectopia. Incidence of displacement was not found to vary significantly with doctor. None of the ectopic cases had severe side effects (pain or heavy bleeding) after insertion. In each case displacement was found to have occurred between 1 week and 6 months postinsertion, 2 of them within 2 weeks. It is probably that the later diagnosis of the others was due to the patient not having noticed the disappearance of the threads. It is concluded that ectopia is due to uterine perforation and not to progressive migration. The different positions in which the device was found when it was removed by laparotomy indicated that such perforation was due to the structure of the device and the resistance of the uterine cavity. Through modification of the loop this complication could be avoided. Disappearance of the threads did not necessarily mean that ectopia had occurred, but it was an important sign, especially if it occurred early on after insertion. With respect to abnormally positioned devices, it was not thought to be a reason for IUD removal, espcially since the abnormal positioning was found to have occurred in every case in an abnormally positioned uterus.^ieng