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The shortage of donor organs and the long waiting lists have increased the need to better select liver transplant candidates using predictors of success. We reviewed the results of 29 liver transplantations performed from January 2002 to February 2003 analyzing the correlations with early mortality (30 days) of patient data, pretransplant laboratory data, warm ischemia time, intraoperations blood unit transfusions, and postoperative complications of prolonged mechanical ventilation, dialysis, and infection. Overall early mortality was 27.6% and 44% in fulminant hepatic failure (n = 9), there were four retransplants with one death, and two intraoperative deaths. Only pretransplant bilirubin (P =.045) and postoperative lactate levels (P =.002) were significantly different between alive versus dead patients. In this small population bilirubin was more related to death than the MELD score. Lactate levels, nonspecific predictor of death in shock syndromes were probably related to septic complications.

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Biliary complications have been reported in 9% to 34% of liver transplant patients. Although most centers seem to prefer a duct-to-duct anastomosis without a T-tube when feasible, the best method of biliary reconstruction remains controversial. The aim of this study was to review our experience on reconstruction of the biliary tract without drainage. Forty-one patients underwent 45 liver transplants over two periods. Forty patients underwent 15 liver transplants from October 1992 to March 1995; and 27 underwent 30 liver transplants from January 2002 to February 2003. Our standard biliary reconstruction was an end-to-end anastomosis without drain. The overall actuarial survival was 72.7% at 1 year, 64.7% at 3 years, and 56.6% at 5 years. The mean follow-up was 23 months. Eight patients (22.2%) developed biliary tract complications: five patients papillary dysfunction (13.9%); two, biliary stricture (5.5%); and one, biliary sludge without evidence of stricture (2.8%). Papillary dysfunction represented 62.5% of all complications. Biliary reconstruction without drainage may be routinely performed since the complications are only those not related to the T-tube.

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Extremely low frequency (ELF) magnetic fields seem to have a reproducible influence on cells in transitional states, such as cells during the embryonic and early postnatal periods. Intense and continuous serotonergic synaptic growth is present during the first 2 weeks of postnatal development, paralleled by 5-HT content in the brain, so, the effect of ELF on 5-HT content in the cerebral cortex and pineal gland was determined in growing rats exposed during pregnancy, and in normal controls. The results showed a significant 5-HT increase at birth, 15 and 21 days, in the cerebral cortex. No differences were found in the pineal gland. These short MF exposures had a long term effect on cerebral cortex 5-HT, possibly starting since the fetal period. The relevance of the present findings are discussed as related to the serotonin trophic role on the brain cortex.

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In Pseudomonas putida U, the degradation of n-alkanoic and n-phenylalkanoic acids is carried out by two sets of beta-oxidation enzymes (betaI and betaII). Whereas the first one (called betaI) is constitutive and catalyses the degradation of n-alkanoic and n-phenylalkanoic acids very efficiently, the other one (betaII), which is only expressed when some of the genes encoding betaI enzymes are mutated, catabolizes n-phenylalkanoates (n > 4) much more slowly. Genetic studies revealed that disruption or deletion of some of the betaI genes handicaps the growth of P. putida U in media containing n-alkanoic or n-phenylalkanoic acids with an acyl moiety longer than C4. However, all these mutants regained their ability to grow in media containing n-alkanoates as a result of the induction of betaII, but they were still unable to catabolize n-phenylalkanoates completely, as the betaI-FadBA enzymes are essential for the beta-oxidation of certain n-phenylalkanoyl-CoA derivatives when they reach a critical size. Owing to the existence of the betaII system, mutants lacking betaIfadB/A are able to synthesize new poly 3-OH-n-alkanoates (PHAs) and poly 3-OH-n-phenylalkanoates (PHPhAs) efficiently. However, they are unable to degrade these polymers, becoming bioplastic overproducer mutants. The genetic and biochemical importance of these results is reported and discussed.

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A novel bioactive macrolide, IB-96212 has been isolated from the fermentation broth of a marine actinomycete, L-25-ES25-008. The strain belongs to the genus Micromonospora. The macrolide showed a very strong cytotoxic activity against P-388, and lower but significant activity against A-549, HT-29, and MEL-28 cell lines. We describe the isolation, taxonomy and fermentation of the producing strain as well as the isolation of IB-96212.

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IB-96212, is a new member of spiroketal containing macrolide class of fermentation-derived natural products isolated from mycelial extracts of Micromonospora sp. The structure consists of a new aglycone which possesses a 26-membered macrolide ring system and of one deoxy sugar identified as L-rhodinose, this structure represents the first reported spiroketal macrolide natural product related to other macrolides, such as oligomycins, dunaimycins, citovaricin, rutamycin and ossamycin.

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Novel biodegradable bacterial plastics, made up of units of 3-hydroxy-n-phenylalkanoic acids, are accumulated intracellularly by Pseudomonas putida U due to the existence in this bacterium of (i) an acyl-CoA synthetase (encoded by the fadD gene) that activates the aryl-precursors; (ii) a beta-oxidation pathway that affords 3-OH-aryl-CoAs, and (iii) a polymerization-depolymerization system (encoded in the pha locus) integrated by two polymerases (PhaC1 and PhaC2) and a depolymerase (PhaZ). The complete assimilation of these compounds requires two additional routes that specifically catabolize the phenylacetyl-CoA or the benzoyl-CoA generated from these polyesters through beta-oxidation. Genetic studies have allowed the cloning, sequencing, and disruption of the genes included in the pha locus (phaC1, phaC2, and phaZ) as well as those related to the biosynthesis of precursors (fadD) or to the catabolism of their derivatives (acuA, fadA, and paa genes). Additional experiments showed that the blockade of either fadD or phaC1 hindered the synthesis and accumulation of plastic polymers. Disruption of phaC2 reduced the quantity of stored polymers by two-thirds. The blockade of phaZ hampered the mobilization of the polymer and decreased its production. Mutations in the paa genes, encoding the phenylacetic acid catabolic enzymes, did not affect the synthesis or catabolism of polymers containing either 3-hydroxyaliphatic acids or 3-hydroxy-n-phenylalkanoic acids with an odd number of carbon atoms as monomers, whereas the production of polyesters containing units of 3-hydroxy-n-phenylalkanoic acids with an even number of carbon atoms was greatly reduced in these bacteria. Yield-improving studies revealed that mutants defective in the glyoxylic acid cycle (isocitrate lyase(-)) or in the beta-oxidation pathway (fadA), stored a higher amount of plastic polymers (1.4- and 2-fold, respectively), suggesting that genetic manipulation of these pathways could be useful for isolating overproducer strains. The analysis of the organization and function of the pha locus and its relationship with the core of the phenylacetyl-CoA catabolon is reported and discussed.

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Agrochelin, a new alkaloid cytotoxic substance, was produced by the fermentation of Agrobacterium sp. The compound was obtained from the bacterial cells by solvent extraction and purified by silica gel chromatography. Agrochelin (1) and its acetyl derivative (2) exhibited cytotoxic activity.

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Sesbanimides are cytotoxic compounds, originally isolated in 1983 from seeds of the leguminous plants Sesbania drummondii and Sesbania punicea. In this paper we describe the bacterial production of sesbanimides by two "marine Agrobacterium"; strain PH-103 which produces Sesbanimide-A and strain PH-A034C which produces Sesbanimide-C. The isolation and taxonomy of the producing microorganisms, fermentation and isolation of sesbanimides are reported.

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Thiocoraline (1) is a new antitumor antibiotic isolated from the mycelium of Micromonospora sp. L-13-ACM2-092. Its structure was elucidated to be a novel cyclic thiodepsipeptide on the basis of spectroscopic methods.

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Authors review the usefulness of radiographic skull examination in childhood head injury. Two hundred and forty-two patients assisted at the emergency area were prospectively recorded during one year. Data of filiation and epidemiology and symptoms and signs posed by Leonidas as "high risk criteria" to have a skull fracture, were registered. AP and L X-Ray skull were performed in all patients. Thirteen (5.37%) of them had a fracture. Blood discharge from the ear and skull depressed fracture were more frequently found in the fracture group with statistically significant difference (p less than 0.05 and p less than 0.01, respectively). The probability of positive finding was 8.8 for blood discharge from the ear, 17.6 for skull depressed fracture and 4.4 for bilateral black eyes. Because of no correlation between clinical and radiological findings, the radiographic skull examination must be systematically performed in every head injury if the purpose is to diagnose a fracture.

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A very large percentage of Mexico's population living in rural areas lacks resources for health care. Any new effort to provide such care must emphasize the health of the infant population because of the high percentage of infants in the country. Plans made at the national level have not been correlated with the conditions that exist in rural areas. For example, the majority of university programs are oriented toward urban medical practice, and the construction of more schools of medicine to solve the problem of doctors in rural areas is based on a mistaken premise. This problem has not been solved even in developed countries such as the United States where, as in Mexico, graduates in medicine migrate to the cities where optimal conditions are met for practicing the type of medicine for which they have been trained. Furthermore, it is both expensive and illogical to maintain urban doctors in rural areas where they cannot practice their profession for lack of resources; to do so is to deny the purpose of their education (27). Conventional schools of medicine, for reasons of investment and of structure, should teach only very selected groups of students who, on finishing their training, are fully capacitated to practice specialized medicine. A different system is required if we are to provide adequate health care in the rural communities. A system such as that described herein, adapted to the real need of rural communities, would avoid the necessity to create dysfunctional bureaucracies and would not destroy those institutions which have proved useful in the past. This study should be considered as one of the many pilot programs that should be initiated in order to determine the type of program that would best solve the problem of health care in rural Mexico. Other programs already being considered at the National Autonomous University of Mexico include the A36 plan of the Faculty of Medicine, now in operation; the work of C. Biro carried out in Netzahualcoyotl City (both focused on providing medical care to the urban poor); and the Open University program. Unless an efficient program designed to meet the needs of rural communities is quickly put into operation, Mexico will, in the near future, be facing the same problems now confronting Southeast Asia.

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