Microbiological Profile, Prevalence, and Characterization of Salmonella enterica in Peanuts, Pecans, Raisins, Sun-Dried Tomatoes, and Chocolate Sprinkles Sold in Bulk in Markets in Querétaro, Mexico.

ABSTRACT: In Mexico, the prevalence of Salmonella enterica in low-water-activity foods and its link to outbreaks are unknown. The aim of this study was to determine the microbiological profile and the prevalence of S. enterica in several low-water-activity foods, including peanuts, pecans, raisins, sun-dried tomatoes, and chocolate sprinkles, purchased in retail establishments in Querétaro, Mexico. Seventy samples of each food item sold in bulk were purchased. Aerobic plate count, molds, yeasts, total coliforms, Escherichia coli, and Staphylococcus aureus were quantified in 10-g samples. The prevalence of S. enterica in 25-g samples was determined. From positive samples, S. enterica isolates (60) were characterized based on their antimicrobial susceptibility to 14 antibiotics, the presence-absence of 13 virulence genes, and serotype. The concentration of aerobic plate count, molds, yeasts, total coliforms, and E. coli ranged from 3.1 to 5.2 log CFU g-1, from 2.0 to 2.4 log CFU g-1, from 2.0 to 3.0 log CFU g-1, from 0.6 to 1.1 log most probable number (MPN) g-1, and from 0.5 to 0.9 log MPN g-1, respectively. S. aureus was not detected in any sample (<10 CFU g-1). The prevalence of S. enterica in chocolate sprinkles, raisins, peanuts, pecans, and sun-dried tomatoes was 26, 29, 31, 40, and 52%, respectively. Most isolates (68.3%) were resistant to at least one antibiotic. Chromosome-associated virulence genes were found in all isolates, and only one strain had sopE, and 98.3% of the isolates were grouped in the same virulotype. Among the isolates, the most frequent serotype was Tennessee (51 of 60). According to the characteristics evaluated, we grouped the isolates into 24 clusters. The elevated prevalence of S. enterica highlights the role of low-water-activity food items sold in bulk at markets as potential vehicles for pathogen transmission. Regardless of the low variability among S. enterica isolates, their characterization could be helpful to elucidate which strains are circulating in these foods for improving epidemiological surveillance.

Three-dimensional Fourier transform evaluation of sequences of spatially and temporally modulated speckle interferograms.

Phase evaluation methods based on the 2D spatial Fourier transform of a speckle interferogram with spatial carrier usually assume that the Fourier spectrum of the interferogram has a trimodal distribution, i. e. that the side lobes corresponding to the interferential terms do not overlap the other two spectral terms, which are related to the intensity of the object and reference beams, respectively. Otherwise, part of the spectrum of the object beam is inside the inverse-transform window of the selected interference lobe and induces an error in the resultant phase map. We present a technique for the acquisition and processing of speckle interferogram sequences that separates the interference lobes from the other spectral terms when the aforementioned assumption does not apply and regardless of the temporal bandwidth of the phase signal. It requires the recording of a sequence of interferograms with spatial and temporal carriers, and their processing with a 3D Fourier transform. In the resultant 3D spectrum, the spatial and temporal carriers separate the conjugate interferential terms from each other and from the term related to the object beam. Experimental corroboration is provided through the measurement of the amplitude of surface acoustic waves in plates with a double-pulsed TV holography setup. The results obtained with the proposed method are compared to those obtained with the processing of individual interferograms with the regular spatial-carrier 2D Fourier transform method.

Effects of hypercapnia on the electroretinogram in sevoflurane and isoflurane anaesthetized dogs.

To evaluate the effects of induced hypercapnia on the electroretinogram (ERG) in beagle dogs anaesthetized with isoflurane and sevoflurane. Binocular, full-field flash photopic and scotopic ERGs were obtained from six healthy neutered female beagle dogs. In order to determine Vmax and the photopic negative response (PhNR), photopic ERG luminance-response curves were generated with 17 different light stimuli. Photopic flicker ERGs were obtained at 30-Hz temporal frequency. Scotopic ERGs were recorded after 35 min of dark adaptation. For all animals, this procedure was performed once in four different sessions: isoflurane + end-tidal [CO(2)] at 35 mmHg +/- 3 mmHg (ISON), isoflurane + end-tidal [CO(2)] at 65 mmHg +/- 3 mmHg (ISOH), sevoflurane + end-tidal [CO(2)] at 35 mmHg +/- 3 mmHg (SEVON), isoflurane + end-tidal [CO(2)] at 65 mmHg +/- 3 mmHg (SEVOH). In photopic conditions, b-wave amplitudes were significantly smaller in hypercapnic groups (ISON = 170.6 +/- 12.1 microV; ISOH = 132.6 +/- 24.9 microV; SEVON = 170.9 +/- 14.4 microV; SEVOH = 130.2 +/- 22.8 microV). Similarly, in scotopic conditions, b-wave amplitudes were significantly decreased when CO(2) was increased (ISON = 89.4 +/- 14.7 microV; ISOH = 58.2 +/- 17.6 microV; SEVON = 93.4 +/- 24.1 microV; SEVOH = 56.2 +/- 22.2 microV). Flicker peak times were significantly increased in hypercapnic groups (ISON = 25.9 +/- 0.4 ms; ISOH = 27.7 +/- 1.2 ms; SEVON = 25.9 +/- 1.5 ms; SEVOH = 27.2 +/- 0.7 ms). Our results clearly indicate that induced hypercapnia significantly alters the genesis of the electroretinogram at level of ON-pathway and suggest that OFF-pathway is unaffected and that ERGs obtained from isoflurane or sevoflurane anaesthetized dogs are almost identical. Control of hypercapnia must be taken into consideration when ERGs are performed under inhaled anaesthesia in dogs.

Antibiotics for asymptomatic bacteriuria in pregnancy.

BACKGROUND: Asymptomatic bacteriuria occurs in 2% to 10% of pregnancies and, if not treated, up to 30% of mothers will develop acute pyelonephritis. Asymptomatic bacteriuria has been associated with low birthweight and preterm delivery. OBJECTIVES: To assess the effect of antibiotic treatment for asymptomatic bacteriuria on persistent bacteriuria during pregnancy, the development of pyelonephritis and the risk of low birthweight and preterm delivery. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (January 2007). SELECTION CRITERIA: Randomized trials comparing antibiotic treatment with placebo or no treatment in pregnant women with asymptomatic bacteriuria found on antenatal screening. DATA COLLECTION AND ANALYSIS: We assessed trial quality. MAIN RESULTS: Fourteen studies were included. Overall the study quality was poor. Antibiotic treatment compared to placebo or no treatment was effective in clearing asymptomatic bacteriuria (risk ratio (RR) 0.25, 95% confidence interval (CI) 0.14 to 0.48). The incidence of pyelonephritis was reduced (RR 0.23, 95% CI 0.13 to 0.41). Antibiotic treatment was also associated with a reduction in the incidence of low birthweight babies (RR 0.66, 95% CI 0.49 to 0.89) but a difference in preterm delivery was not seen. AUTHORS' CONCLUSIONS: Antibiotic treatment is effective in reducing the risk of pyelonephritis in pregnancy. A reduction in low birthweight is consistent with current theories about the role of infection in adverse pregnancy outcomes, but this association should be interpreted with caution given the poor quality of the included studies.

Typing of Haemophilus paragallinarum strains by using enterobacterial repetitive intergenic consensus-based polymerase chain reaction.

The enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) technique was used for fingerprinting of reference strains and Mexican isolates of Haemophilus paragallinarum. A total of nine ERIC patterns were given by the nine serovar reference strains of this bacteria. Two Modesto (C-2) reference strains from different sources showed the same ERIC pattern. Seventeen ERIC patterns were obtained among 29 Mexican isolates included in the study, belonging to serovars prevalent in Mexico (A-1, A-2, B-1, and C-2). Obtained results indicate that the ERIC-PCR technique could be used as a molecular laboratory tool for subtyping of H. paragallinarum.

Treatments for symptomatic urinary tract infections during pregnancy.

BACKGROUND: Urinary tract infections, including pyelonephritis, are serious complications that can result in significant maternal and neonatal morbidity and mortality. There is a large number of drugs, and combination of them, available to treat urinary tract infections, most of them tested in non-pregnant women. Attempts to define the optimal antibiotic regimen for pregnancy has, therefore, been problematic. OBJECTIVES: The objective of this review was to try to determine, from the best available evidence from randomized control trials, which agent is most effective for the treatment of symptomatic urinary tract infections during pregnancy in terms of cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change of antibiotic, and incidence of prolonged pyrexia. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register (January 2003) and reference lists of articles were searched. SELECTION CRITERIA: All trials were considered where the intention was to allocate participants randomly to one of at least two alternative treatments for any symptomatic urinary tract infection. DATA COLLECTION AND ANALYSIS: Both reviewers assessed trial quality and extracted data. MAIN RESULTS: Eight studies were included, recruiting a total of 905 pregnant women. In most of the comparisons there were no significant differences between studied treatments with regard to cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change of antibiotic and incidence of prolonged pyrexia. Only when cefuroxime and cephradine were compared, were there better cure rates (29/49 versus 41/52) and less recurrences (20/49 versus 11/52) in the cefuroxime group, but the sample size is insufficient to ensure that differences found in the effect of the drugs were real. REVIEWER'S CONCLUSIONS: Although antibiotic treatment is effective for the cure of urinary tract infections, there are insufficient data to recommend any specific treatment regimen for symptomatic urinary tract infections during pregnancy. All the antibiotics studied were shown to be very effective in decreasing the incidence of outcomes measured. Complications were very rare. All included trials had very small sample sizes to try to detect important differences between treatments. Future studies should evaluate the most promising antibiotics, in terms of class, timing, dose, acceptability, maternal and neonatal outcomes and costs.

Effect of oxygen on sleep and breathing in patients with interstitial lung disease at moderate altitude.

OBJECTIVE: To investigate the impact of oxygen on sleep and breathing in patients with interstitial lung disease (ILD) in Mexico City, at 2,240 m of altitude. PARTICIPANTS: Nineteen ILD patients with a mean FVC of 58 +/- 17% pred. (SD) and a mean PaO(2) of 51 +/- 6 mm Hg were recruited from a pulmonary clinic in a tertiary referral center. In addition, 14 normal control subjects, matched for age and gender, were studied. All patients underwent two consecutive full polysomnographies (PSG), one breathing room air and one breathing supplementary oxygen through nasal prongs, in random order. Controls were studied for one night breathing room air. RESULTS: The mean oxygen saturation (SaO(2)) in ILD patients was 82.3 +/- 9.1% during sleep on air and 94.8 +/- 2.9% on oxygen (p < 0.001). In controls it was 92.9 +/- 1.9% (p < 0.001). Sleep efficiency was similar in patients and controls (75 vs. 82%, p > 0.05) and did not change with oxygen (77%). Arousal index was 12.4 +/- 6.9.h(-1) in ILD patients breathing room air and 12.9 +/- 9.1.h(-1) breathing oxygen while in controls it was 11.4 +/- 5.4.h(-1). Breathing frequency (f) during sleep was 24.7 +/- 4.2 in ILD patients and decreased breathing oxygen to 22.5 +/- 3.6 (p < 0.001) but was still higher than in controls (15.6 +/- 2.7; p < 0.001). Similarly, the heart rate (HR) in ILD and controls was 79 +/- 12 and 68 +/- 8, respectively (p < 0.001), and decreased to 68 +/- 4 when patients breathed oxygen (p < 0.001). CONCLUSIONS: Oxygen substantially decreases HR and f, but does not normalize the f in ILD patients. The impact of hypoxia on sleep efficiency and arousal index was not demonstrable in our patients acclimatized to moderate altitude.

Polyacrylonitrile membrane interposition between a xenograft and a patient in fulminant liver failure: the concept of xenohemodiafiltration in clinical practice.

Fulminant hepatic failure is an important cause of morbidity and mortality in intensive care units. Conventional therapies are not sufficiently effective. Liver transplantation may be life saving, but a "bridge therapy" is needed until transplantation is performed. Hepatic extracorporeal xenohemodiafiltration (XHDF) is aimed at the transitory support of a patient with fulminant hepatic failure. The first clinical case of XHDF is presented. The system consisted of cross-circulation between a porcine liver and a patient with fulminant liver failure through a polyacrylonitrile membrane. The procedure lasted for 5 hours and produced hemodynamic, biochemical, and metabolic improvements. Intracranial pressure decreased from 34 to 5 cm H2O, serum ammonia fell from 673 to 370 ng/dl, lactic acid from 11 to 5.3 mmol/L, and bilirubin from 7.4 to 2.5 mg/dl. Hemodynamic values were maintained stable throughout the procedure. The patient was able to undergo transplantation and remains alive 11 months later. XHDF is a clinical experimental method that can constitute an alternative clinical therapy to support patients with fulminant hepatic failure until an organ is available for transplantation.

Treatments for symptomatic urinary tract infections during pregnancy.

BACKGROUND: Urinary tract infections, including pyelonephritis, are serious complications that can result in significant maternal and neonatal morbidity and mortality. There is a large number of drugs, and combination of them, available to treat urinary tract infections, most of them tested in non-pregnant women. Attempts to define the optimal antibiotic regimen for pregnancy has, therefore, been problematic. OBJECTIVES: The objective of this review was to try to determine, from the best available evidence from randomized control trials, which agent is most effective for the treatment of symptomatic urinary tract infections during pregnancy in terms of cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change of antibiotic, and incidence of prolonged pyrexia. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register and reference lists of articles were searched. SELECTION CRITERIA: All trials were considered where the intention was to allocate participants randomly to one of at least two alternative treatments for any symptomatic urinary tract infection. DATA COLLECTION AND ANALYSIS: Trial quality assessment and data extraction were performed by the two reviewers. MAIN RESULTS: Five studies were included. There were no significant differences between studied treatments with regard to cure rates, recurrent infection, incidence of preterm delivery and premature rupture of membranes, admission to neonatal intensive care unit, need for change antibiotic and incidence of incidence of prolonged pyrexia. REVIEWER'S CONCLUSIONS: Although antibiotic treatment is effective for the cure of urinary tract infections, there are insufficient data to recommend any specific treatment regimen for symptomatic urinary tract infections during pregnancy. All of the antibiotics studied were shown to be very effective in decreasing the incidence of outcomes measured. Complications were very rare. All included trials had very small sample sizes to try to detect important differences between treatments. Future studies should evaluate the most promising antibiotics, in terms of class, timing, dose, acceptability, maternal and neonatal outcomes and costs.

Automated analysis of digital oximetry in the diagnosis of obstructive sleep apnoea.

BACKGROUND: The gold standard diagnostic test for obstructive sleep apnoea (OSA) is overnight polysomnography (PSG) which is costly in terms of time and money. Consequently, a number of alternatives to PSG have been proposed. Oximetry is appealing because of its widespread availability and ease of application. The diagnostic performance of an automated analysis algorithm based on falls and recovery of digitally recorded oxygen saturation was compared with PSG. METHODS: Two hundred and forty six patients with suspected OSA were randomly selected for PSG and automated off line analysis of the digitally recorded oximeter signal. RESULTS: The PSG derived apnoea hypopnea index (AHI) and oximeter derived respiratory disturbance index (RDI) were highly correlated (R = 0.97). The mean (2SD) of the differences between AHI and RDI was 2.18 (12.34)/h. The sensitivity and specificity of the algorithm depended on the AHI and RDI criteria selected for OSA case designation. Using case designation criteria of 15/h for AHI and RDI, the sensitivity and specificity were 98% and 88%, respectively. If the PSG derived AHI included EEG based arousals as part of the hypopnea definition, the mean (2SD) of the differences between RDI and AHI was -0.12 (15. 62)/h and the sensitivity and specificity profile did not change significantly. CONCLUSIONS: In a population of patients suspected of having OSA, off line automated analysis of the oximetry signal provides a close estimate of AHI as well as excellent diagnostic sensitivity and specificity for OSA.

Use of embryonic and somatic cells for production of transgenic domestic animals.

In contrast to the highly developed genetic modification systems available for manipulating the mouse genome, at this time only simple gain of function modifications can be undertaken in domestic species. Clearly, the greatest barrier to gene targeting in domestic species has been the unavailability of cell lines that can be modified in vitro and still be used to generate a living organism. In the mouse, the embryonic stem (ES) cells and embryonic germ (EG) cells have fulfilled that role. While the nuclear transfer procedures have solved this problem in sheep and cattle, in swine ES and EG cells are still needed. In addition, targeting in domestic species is affected by the need to develop targeting constructs containing isogenic DNA regions. As a result, it is necessary to isolate the gene of interest, sequence required regions, and develop isogenic targeting constructs by technologies such as long-range PCR. On the positive side, enrichment protocols developed in the mouse can be applied to domestic species, thus facilitating the identification of correctly modified cell lines. Hence, progress in mammalian cloning, the development of EG cell lines, and advances in gene targeting presently allows the introduction of precise genetic modifications into the domestic animal genome.

Usefulness of inhaled furosemide in a bronchial asthma attack.

Furosemide administered through repeated dose inhalation has antiinflammatory effects on the airways. We carried out a study to measure the adjuvant effect of this drug with salbutamol inhalation in asthmatic patients presenting an acute or chronic asthma attack. We studied 50 patients, 25 of whom were given salbutamol (0.5%-1 cc) every 12 h and placebo every 12 h. All patients underwent spirometry on the first day and at the end of the treatment (5 days). Peak flow was recorded twice a day as well as daily diuresis and body weight. Peak flow in the morning increased 13.8 l/min in the group given salbutamol and placebo; in group given furosemide, the increase was 2.2 l/min, with statistically significant differences. Peak flow in the evening showed no sizeable differences. The same was true with spirometric variables (FVC, FEV1 and FEF 25-75), which improved greatly in both groups, but without a considerable difference. Diuresis increased in the group given furosemide (510.80 ml; in the group given placebo the increase was 310.20) without a significant difference. Analysis of body weight showed that in the group given furosemide average weight decreased from 140.4 to 138.5 lbs (52.4 to 51.7 kg); in the group given placebo, it increased from 130.3 to 132.6 lbs (48.6 to 49.5 kg). Statistical analysis was significant. We concluded that administering furosemide by inhalation for 5 days as adjuvant treatment to salbutamol in patients presenting with acute or chronic asthma attack is not superior to treatment using salbutamol and placebo.

[Primary tracheobronchial amyloidosis. Report of a case]. / Amiloidosis traqueobronquial primaria. Reporte de un caso.

We present a patient with primary tracheobronquial amiloidosis diffuse, presenting with asthma-like dysnea. The diagnosis was made through the broncoscopy and biopsy of infiltrated bronchial mucosa.

Tricuspid annuloplasty and ventricular plication for Ebstein's malformation.

BACKGROUND: Seven patients with the diagnosis of Ebstein's malformation of the tricuspid valve were operated on. Mean age was 12 years (range, 7 to 16 years). All were cyanotic, with severe tricuspid regurgitation. Thromboembolism was not present. No associated cardiac malformations were present. METHODS: Surgical repair included tricuspid annuloplasty associated with longitudinal plication of the atrialized portion of the right ventricle. This was attained by approximating the anterior-posterior commissure with either the posterior-septal commissure or the septal leaflet remnant. The thin atrialized ventricular wall thus excluded remained as a cul du sac and was plicated by suturing along the longitudinal axis of the heart. When present, the dysplastic posterior leaflet was included in the plication. In essence, a monocuspid right atrioventricular valve was fashioned out of the anterior leaflet. The remaining septal leaflet played a minimal functional role. No additional procedures for treatment of arrhythmia were associated with the technique described. RESULTS: The postoperative course was uneventful in all patients. Mean follow-up is 4.3 years (range, 1 to 10 years). Doppler echocardiographic studies reveal satisfactory monocusp valve function in all patients, with adequate coaptation of the anterior leaflet and the septal structures. CONCLUSIONS: This technique seems applicable to most forms of Ebstein's malformation and is reproducible. The technique relies on the adequate mobilization of the anterior leaflet. Occasionally it is necessary to free fibrous adhesions of the leaflet to the underlying ventricular surface.

Assessment of the bronchodilator effect of inhaled furosemide compared to salbutamol in asthmatic patients.

To compare the bronchodilator effects of high-dose inhaled furosemide, we studied 80 patients who were nonsmokers presenting some degree of bronchial obstruction. Of these patients, 40 were given salbutamol (1%) aerosol and the remaining 40 were given furosemide aerosol (100 mg). Respiratory functional tests were conducted at 10 min and 30 min, as well as measurement of pulse and blood pressure. Patients in the salbutamol group showed an improvement in forced expiratory volume (FEV1) of 7.9% at 10 min and 30 min, and the group given furosemide improved 6.9% (p > 0.05). Systolic blood pressure showed a slight increase of 2 mmHg in the salbutamol group and a decrease of 6 mmHg in the furosemide group (p < 0.05). The same occurred for diastolic blood pressure (p < 0.05). Pulse increased from 73.7 to 75.2 beats per min in the salbutamol group; however, in the furosemide group, pulse declined from 73.7 to 71.8 beats per min (p < 0.05). We conclude that furosemide at a dose of 100 mg has the same bronchodilator effect as salbutamol, as measured by FEV1 and forced expiratory flow of 25% to 75%. Furosemide was also related with a mild hypotensive effect and drop in pulse.

Aortico-right ventricular tunnel.

A successful operation on an infant with a tunnel through which the aorta communicated with the right ventricle is reported. The diagnosis was suspected preoperatively on the basis of two-dimensional Doppler color echocardiography and confirmed by cardiac catheterization. The aortico-right ventricular tunnel originated independently from the left coronary ostium and above the sinus of Valsalva. Patch closure from inside the tunnel under deep hypothermia was successfully performed. Follow-up is satisfactory 5 years later.

Factors affecting the efficiency of introducing precise genetic changes in ES cells by homologous recombination: tag-and-exchange versus the Cre-loxp system.

The introduction of genetic modifications in specific genes by homologous recombination provides a powerful tool for elucidation of structure-function relationships of proteins of biological interest. Presently, there are several alternative methods of homologous recombination that permit the introduction of small genetic modifications in specific loci. Two of the most widely used methods are the tag-and-exchange, based on the use of positive-negative selection markers, and the Cre-loxP system, based on the use of a site-specific recombinase. The efficiency of detection of targeting events at different loci using the two systems was compared. Additionally, we analysed how the distance between two gene markers placed within the region of homology of a targeting vector affects the rate at which both markers are introduced into the locus during the homologous recombination event. Our results indicate that the method based on the use of positive-negative selection markers was less efficient than the Cre-loxP based system, irrespective of locus or type of positive-negative selection. It was also determined that as the distance between the selectable marker and the genetic modification being introduced increases, there is a progressive reduction in the efficiency of detecting events with the desired genetic modification.

Polyacrylonitrile membrane interposition between a xenograft and an animal in fulminant liver failure. The concept of xenohemodiafiltration.

In fulminant liver failure (FLF) there is need for support as a bridge to liver transplantation. Based on the concepts of hemofiltration and xenotransplantation, the authors present a model of liver support in FLF. The authors performed a portacaval shunt and ligature of the hepatic artery in 12 pigs. In six pigs (Group A) continuous hemofiltration through a polyacrylonitrile membrane was performed. Six isolated dog's livers were catheterized through the portal vein and perfused with autologous erythrocytes, albumin, and electrolytes in a closed circuit. With the use of the auxiliary liver, the circuit was connected to one of the lateral outlets of the hemofilter, while the other lateral outlet was connected to the portal vein through the pump. Thus, a polyacrylonitrile exchange membrane was created between the blood of the pig with FLF and the auxiliary liver's circulation. In Group B (controls), six pigs were connected directly to the auxiliary liver through a pump. In Group A, the auxiliary liver worked for 8 hr, without evidence of macroscopic or histologic damage. Lactic acid and ammonia levels improved: lactic acid, 8.2 +/- 6 mmol/L to 1.6 +/- 1 mmol/L; ammonia 487 +/- 110 micrograms/dl to 117 +/- 13 micrograms/dl, p < 0.1. The lidocaine clearing (MEGX) test results remained at functional levels (> 90 ng/ml) at the end of the perfusion. In Group B, the perfusion was discontinued at 60 +/- 15 min because of evidence of necrosis of the auxiliary liver. Lactic acid levels increased from 8.19 +/- 1.1 mmol/L to 13 +/- 4 mmol/L, ammonia levels remained high (390 +/- 15 micrograms/dl to 480 +/- 80 micrograms/dl), and the MEGX test results showed levels below functional activity by the end of the perfusion (45 +/- 30 ng/ml). The authors conclude that the concept of xenohemodiafiltration based on the interposition of a polyacrylonitrile membrane between a xenograft and an animal in FLF is adequate to support functions of detoxification and could be used in the future in the support of patient with FLF.

Bidirectional cavopulmonary shunt in patients with multiple risk factors.

BACKGROUND: Twenty-five patients in whom a modified Fontan operation was deferred because of multiple risk factors underwent a bidirectional cavopulmonary shunt. Two or more of the following risk factors were present in all: age less than 1 year, severe pulmonary artery distortion, impaired left ventricular function, subaortic obstruction, anomalous systemic-pulmonary venous connection, atrioventricular valve incompetence, and increased mean pulmonary artery pressure. METHODS: Additional procedures included take-down of systemic-pulmonary artery shunt, atrial septectomy, pulmonary artery reconstruction, bulboventricular foramen enlargement, and atrioventricular valve repair. RESULTS: There were three hospital deaths (12%). Mean follow-up is 21 months. There was no late mortality. Mean oxygen saturation increased from 71% to 83%. Results obtained from pulmonary artery reconstruction, enlargement of bulboventricular foramen, and atrioventricular valve repair were satisfactory for the patients in whom these risk factors were present preoperatively. Ventricular function also improved in the survivors in whom it was previously deteriorated, this being related to the suppression of the sources of ventricular volume overload. CONCLUSIONS: In this risk group of patients for a modified Fontan operation, a bidirectional cavopulmonary shunt provided adequate palliation at reasonable low risk. Early bidirectional cavopulmonary shunt would minimize complications originating from systemic-pulmonary shunts such as pulmonary artery distortion and the potential harm of chronic ventricular volume overload.