Infection of mice by the enteroaggregative E. coli strain 042 and two mutant derivatives overexpressing virulence factors: impact on disease markers, gut microbiota and concentration of SCFAs in feces.

Several pathogenic Escherichia coli strains cause diarrhea. Enteroaggregative E. coli (EAEC) strains are one of the diarrheagenic pathotypes. EAEC cells form a "stacked-brick" arrangement over the intestinal epithelial cells. EAEC isolates express, among other virulence determinants, the AggR transcriptional activator and the aggregative adherence fimbriae (AAF). Overexpression of the aggR gene results in increased expression of virulence factors such as the aff genes, as well as several genes involved in specific metabolic pathways such as fatty acid degradation (fad) and arginine degradation (ast). To support the hypothesis that induction of the expression of some of these pathways may play a role in EAEC virulence, in this study we used a murine infection model to evaluate the impact of the expression of these pathways on infection parameters. Mice infected with a mutant derivative of the EAEC strain 042, characterized by overexpression of the aggR gene, showed increased disease symptoms compared to those exhibited by mice infected with the wild type (wt) strain 042. Several of these symptoms were not increased when the infecting mutant, which overexpressed aggR, lacked the fad and ast pathways. Therefore, our results support the hypothesis that different metabolic pathways contribute to EAEC virulence.

Dietary supplementation with spray-dried porcine plasma has prebiotic effects on gut microbiota in mice.

In animal models of inflammation and in farm animals, dietary inclusion of spray-dried porcine plasma (SDP) reduces mucosal inflammation. Here, we study whether these effects could be mediated by changes in the intestinal microbiota and if these changes are similar to those induced by oral antibiotics. Weaned 21-day-old C57BL/6 mice were divided into 3 groups: the CTL group, fed the control diet; the COL group, administered low doses of neomycin and colistin; and the SDP group, supplemented with 8% SDP. After 14 days, analysis of the fecal microbiome showed that the microbiota profiles induced by SDP and the antibiotics were very different, thus, SDP has prebiotic rather than antibiotic effects. At the phylum level, SDP stimulated the presence of Firmicutes, considerably increasing the lactobacilli population. It also enhanced the growth of species involved in regulatory T-lymphocyte homeostasis and restoration of the mucosal barrier, as well as species negatively correlated with expression of pro-inflammatory cytokines. At the mucosal level, expression of toll-like receptors Tlr2, Tlr4 and Tlr9, and mucous-related genes Muc2 and Tff3 with regulatory and barrier stability functions, were increased. SDP also increased expression of Il-10 and Tgf-ß, as well as markers of macrophages and dendritic cells eventually promoting an immune-tolerant environment.

[Anomalous origin of the right pulmonary artery from the ascending aorta. Its echo-Doppler diagnosis]. / Origen anómalo de la arteria pulmonar derecha desde la aorta ascendente. Diagnóstico eco-Doppler.

The anomalous origin of the right pulmonary artery from the ascending aorta is a rare malformation. Its diagnosis and early surgical treatment are necessary to avoid its fatal outcome. We present the pulsed and color echo-Doppler findings in a patient with this pathology.

[Left aorto-ventricular tunnel. Diagnosis with transthoracic and transesophageal echo-Doppler]. / Túnel aorto-ventricular izquierdo. Diagnóstico mediante eco-Doppler transtorácica y transesofágica.

Aortic-left ventricular tunnel is an infrequent congenital heart lesion consisting of an abnormal tubular-shaped communication between the aortic root and the left ventricle that bypasses the aortic valve. It is clinically undistinguishable from aortic insufficiency. Its prompt and precise diagnosis is crucial since early surgical treatment is definitely indicated, in contrast to aortic insufficiency. In our case, two-dimensional and pulsed color-flow Doppler imaging established the diagnosis, and the transesophageal approach was a great aid in detecting the aortic opening with its turbulent diastolic flow, and in tracing its intramyocardial course. This paper may be of interest not just as a new case-report but insofar as it stresses how importantly the transthoracic and transesophageal echocardiographic and Doppler scanning contributes to its diagnosis and therapeutic indication.

[Total anomalous pulmonary venous return in children: importance of echocardiographic diagnosis and early surgery]. / Retorno venoso pulmonar total anómalo en pediatría: importancia del diagnóstico ecocardiográfico y de la cirugía precoz.

OBJECTIVE: We studied patients who underwent surgical repair for total anomalous pulmonary venous return at our hospital. We report the importance of diagnosis by echocardiographic imaging before surgical treatment. METHODS: Within the period of 1990-1999, fourteen patients underwent surgical repair of this cardiopathy in our hospital. The type of anomalous drainage was supracardiac in 6 patients, infracardiac in 4, to the coronary sinus in 1, and mixed-type in 3 patients. Eleven cases were diagnosed with an echo-Doppler study, the findings being confirmed intraoperatively. RESULTS: There were 2 early deaths: one occurred in the operating room in a patient with a small left ventricle, and the second one was 35 days postoperatively as a result of a septic complication. Early in the postoperative period our primary goal has steadily been the control and treatment of pulmonary hypertension. After a mean follow-up time of 50 months, only 1 patient needed to be reoperated on and the remainder are symptomless. CONCLUSIONS: That sufficient diagnostic data on total anomalous pulmonary venous return can reliably be obtained by ultrasound scanning so that surgery can be promptly undertaken, and that its surgical risk is currently low and mid-term post-repair outcome is fairly good.

[Anatomical correction in transposition of the great arteries and double-outlet right ventricle. Our initial experience]. / Corrección anatómica en la transposición de grandes arterias y en la doble salida de ventrículo derecho. Experiencia inicial.

INTRODUCTION AND OBJECTIVES: Anatomical correction of transposition of great arteries and double outlet right ventricle with subpulmonary ventricular septal defect is a surgical approach that has not been generally adopted in our clinical environment. Our aim with this paper is reporting on our initial experience with this technique. METHODS: The clinical data and additional investigations are reviewed from 15 infants with transposition of the great arteries and 2 with double outlet right ventricle who underwent anatomical repair, with a postoperative follow-up of one year. RESULTS: The survival rate has been 76% (13 out of 17 cases). The 13 survivors are in good hemodynamic condition, with no treatment whatsoever. Thirteen patients are in sinus rhythm with normal repolarization patterns and 5 patients show a right bundle branch block. Neither aortic nor pulmonary gradients have been detected on Doppler examination, and slight valvular insufficiencies are found at aortic level in 4 patients, pulmonary in 2 and mitral in one. CONCLUSION: Anatomical correction is the method of choice for transposition of the great arteries and double outlet right ventricle with pulmonary-related ventricular septal defect.

[Double-outlet left ventricle with subaortic interventricular defect and pulmonary stenosis: surgical correction with cryopreserved aortic homograft]. / Doble salida ventricular izquierda con comunicación interventricular subaórtica y estenosis pulmonar: corrección quirúrgica con utilización de homoinjerto aórtico crioconservado.

Double outlet left ventricle with subaortic ventricular septal defect and pulmonary stenosis is a very rare congenital heart disease. We present a case of this cardiopathy which underwent correction consisting of ventricular septal defect closure and right ventricular outflow tract reconstruction using a cryopreserved aortic homograft, with a postsurgical follow-up time of 18 months.

[Arterial switch: aortocoronary bypass with interposition of polytetrafluoroethylene (Gore-tex) vascular graft]. / Switch arterial: bypass aortocoronario con interposición de injerto vascular de politetrafluoroetileno (Gore-tex).

We report a case of an infant with transposition of the great arteries accompanied by an unusual coronary artery pattern, in whom an expanded polytetrafluorethylene (Gore-tex) graft to the right coronary artery was used during surgical correction (switch arterial), with a postsurgical follow-up time of 8 months.

[Doppler echocardiography in the postoperative assessment of the arterial switch in the repair of transposition of the great arteries and double outlet right ventricle]. / Ecocardiografía Doppler en la valoración posquirúrgica del switch arterial para la reparación de la transposición de las grandes arterias y la doble salida del ventrículo derecho.

OBJECTIVE: To evaluate the usefulness of Doppler-echocardiography in the follow-up of anatomical repair in transposition of great arteries and double outlet of right ventricle. PATIENTS AND METHODS: 108 Doppler-echo studies, in a follow-up protocol of the first 32 consecutive patients who successfully passed anatomical repair, were analyzed. The mean age for operation was 50 days (6-472 days) (25 patients before 21 days of age) with a mean follow-up time of 406 days (1 day-4.5 years). We studied subjective impression of left ventricular function and its quantification by systolic shortening fraction, the functioning of four heart valves; diagnosis and quantification of stenosis in arterial sutures of neoaorta and neopulmonary, the most useful windows and planes and, finally, the difficulties found during the examination. RESULTS: Thirteen patients (41%) showed a low left ventricular shortening fraction, though 85% of these patients had anomalous ventricular septal motion. Neoaortic valve insufficiency was detected in 12 patients (37%) (mild in 10 and moderate in 2) and neopulmonary valve regurgitation in 14 patients (44%) (mild in 11 and moderate in 3). Stenosis of arterial sutures was detected in: 2 (6%) patients at neopulmonary artery and 1 (3%) at neoaortic artery. The biggest technical difficulty was found in the neopulmonary artery evaluation. CONCLUSIONS: 1) Doppler echocardiography is an excellent method for anatomical and functional evaluation in these patients and is necessary in their follow-up evaluations; 2) Surgical results obtained in this series are good; 3) Left ventricle fractional shortening is misleading in the evaluation of ventricular function in these patients because of the high incidence of abnormal ventricular septal motion, and 4) The study of neopulmonary arteries is often very difficult.

[Results of valvuloplasties with balloon catheter in children. Follow-up using pulsed Doppler. Experience with our first cases]. / Evolución de las valvuloplastias con catéter balón en la edad pediátrica. Seguimiento mediante Doppler pulsado. Experiencia en nuestros primeros casos.

Our series includes the first 19 consecutive patients with pulmonary valvar stenosis who underwent balloon valvuloplasty in our hospital. All of them have been evaluated by an echo-Doppler study at different follow-up times, and in 10 patients the study was also performed prior to the dilatation. The ages ranged between 0.4 and 10 years (mean 3.5 years; standard deviation [SD] 2.53 years). The prevalvuloplasty degree of pulmonic stenosis found at catheterization was quantified as severe in 8 cases (42.11%) with a right ventricular systolic pressure (RVSP) in excess of 90 mmHg, and moderate in 11 cases (57.89%) with an RVSP from 70 to 90 mmHg. Transvalvular gradients were registered between 38 and 110 mmHg (m: 69 mmHg and SD: 15 mmHg). According to catheterization data obtained at the time of valvuloplasty, the procedure was considered ineffective in 2 cases (10.52%), scarcely effective in four (21.05%), and successful in the remaining 13 cases (68.42%). Doppler follow-up was carried out between 1.6 and 31.9 months after valvuloplasty (mean 12.9 months and SD: 10 months). Residual stenoses were estimated by Doppler as mild in 13 cases (68.42%), moderate in four (21.05%) and severe in two (10.52%). Mild pulmonary regurgitation was detected in 10 patients (52%). The 13 patients with a satisfactory result had slight residual gradients at the valvular level that had not been modified with the course of time. Of the 4 cases with a poorly effective dilatation the gradients noted by Doppler increased in three of them, being valvular in all but one in whom the obstruction was catalogued as infundibular.(ABSTRACT TRUNCATED AT 250 WORDS)

Late outcome of Senning and Mustard procedures for correction of transposition of the great arteries.

OBJECTIVES: To evaluate late mortality and morbidity after an atrial switch procedure for correction of transposition of the great arteries (TGA) and to assess predictive factors for adverse outcome. SETTING: Tertiary referral centre. DESIGN AND PATIENTS: Retrospective follow up study of 137 patients surviving hospitalisation for TGA atrial switch procedure (Mustard or Senning) in a single institution and divided into two groups (simple and complex) depending on presurgical anatomy. Several surgical and follow up factors were evaluated during 16.7 (5.6) years' follow up. RESULTS: Late mortality was 5.1% (95% confidence interval 1.37% to 8.84%) with sudden death as the most common cause. No significant difference was found between Mustard and Senning procedures and between the complex and simple groups in terms of mortality. Independent predictive factors for late mortality were a history of supraventricular tachyarrhythmias and advanced New York Heart Association (NYHA) functional class during follow up. A very common finding was development of sinus node dysfunction (47.6%), which had no influence on mortality. There was little need for reintervention (5.1%) and relatively few cases of right ventricular systolic dysfunction (14.6%). During follow up, most patients (96.2%) were in NYHA functional class I-II. CONCLUSIONS: Overall long term outcomes of patients with atrial repair of TGA in the present era are encouraging in terms of late mortality and quality of life. Nevertheless, better outcomes may be offered through improved diagnostic methods for right ventricular function and better management of supraventricular tachyarrhythmias.

[Laser applications in medicine and surgery (author's transl)]. / Le laser et ses applications médico-chirurgicales.

After an analysis of the complex interweaving reactions of laser on biological materials, the laser applications in medicine and surgery are reviewed by the author. In ophthalmology its use is regular but not yet optimal. In otological applications the first results are good. In dermatology favorable results are obtained but the absence of special device had stopped his development. In surgery and endoscopy the best wave length must be chosen in reference to their hemostatic action and cutting, nevertheless in gastroscopy and bronchoscopy the laser seems to bring new therapeutic solutions. In odontology the pulsed lasers are dangerous for therapy but the holographic technique is a fertile research area. The author conclude to the necessary development of researches on the fundamental problems set by the biomedical applications of lasers.

[Scanning electron microscope view of dentin exposed to CO2 laser radiation]. / Aspect en microscopie electronique a balayage de la dentine exposée à un rayonnement laser CO2.

In order to better define the effects of CO2 Laser rays on dentine, 10 healthy human teeth to be removed and 64 recently removed healthy human teeth were prepared and irradiated according to the classic protocol used in clinical periodontics, and observed with a scanning electron microscope. The examination of these samples confirms the phenomena of dentin fusion and recrystallization. But these alterations result in the appearance of a reorganized superficial layer consisting of unevenly juxtaposed craters formed by the pin-point action of the laser beam. These craters present numerous fissures and openings of variable diameter. They do not form a homogeneous surface, since chips may be raised, demonstrating the fragility of the reorganized layer and a lack of cohesion of the underlying dentine. The modified dentine layer also disappears when a curette is used, revealing a very uneven surface crossed with small cracks and where the tubule openings become visible. Our results, unlike many more optimistic studies, still prompt us to exert caution in the systematic use of CO2 lasers in Periodontics.

GSM radiocellular telephones do not disturb the secretion of antepituitary hormones in humans.

It is known that the endocrine system of experimental animals is susceptible to perturbation by radiofrequency (RF) radiation. Because of the recent interest in health and safety issues of cellular telephones, an experiment was designed to evaluate the effect of a 900 MHz RF radiation emitted by a Global System for Mobile radiotelephone (217 Hz impulses, one-eighth duty cycle, 2 W peak power) on human endocrine functions. Twenty healthy male volunteers aged from 19 to 40 were inducted in the present experiment. Each subject was exposed to RF radiation through the use of a cellular phone 2 h/day, 5 days/wk, for 1 month. Subjects were their own control. End points were serum adrenocorticotropin, thyrotropin, growth hormone, prolactin, luteinizing hormone, and follicle stimulating hormone concentrations. These end points were determined in nine weekly blood samples obtained starting 3 weeks before the commencement of the exposure and ending 2 weeks after exposures. All but one blood sample was drawn 48 h after each weekly session. The seventh drawing was performed the morning after the last weekly exposure. Within each individual, the preexposure hormone concentration was used as a control. Results indicated that all hormone concentrations remained within normal physiologic ranges. A difference was not noted among the nine weekly samples in five of six hormones studied. There was a significant change only in thyrotropin concentration, showing a 21% decrease on the seventh sampling. Because this change recovered fully during the postexposure period, it is concluded that 1 month of intermittent exposures to RF radiation from a cellular telephone does not induce a long-lasting or cumulative effect on the hormone secretion rate of the anterior pituitary gland in humans.

Heparin therapy and reversal of protein-losing enteropathy in a case with congenital heart disease.

We describe a patient with tricuspid hypoplasia who developed a protein-losing enteropathy. Having failed to respond to medical and surgical treatments, a heparin regimen was started with immediate decrease in enteric protein loss.

Current status of French research on the biological effects of heavy ions in cosmic radiation as observed in high-altitude balloons.

On casual inspection, cosmic rays may not be considered to pose a biological hazard. Nevertheless, the heavy ion component does produce a significant but very local irradiation. This has been confirmed by the hair whitening in black-haired animals. Experiments with black C 57 mice in balloons at 30,000 m altitude show white-haired tufts along the tracks of heavy ions. Histological and radioautographic studies were carried out; the results are reported. Similar investigations on black rabbits gave similar results and confirm those obtained previously with black mice. In the discussion, we report that tissue damage is amplified. This fact is not yet explained, but suggests reconsideration of the calculation of radiation dosage. The ionization distribution induced by heavy ions is analyzed. We point out that along their tracks the dosage is very important; therefore it is necessary to investigate their biological action, particle by particle, according to their energy and their charge.