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The aim was to understand how interaction of the central carbon and the secondary carnitine metabolisms is affected under salt stress and its effect on the production of L-carnitine by Escherichia coli. The biotransformation of crotonobetaine into L-carnitine by resting cells of E. coli O44 K74 was improved by salt stress, a yield of nearly twofold that for the control being obtained with 0.5 M NaCl. Crotonobetaine and the L-carnitine formed acted as an osmoprotectant during cell growth and biotransformation in the presence of NaCl. The enzyme activities involved in the biotransformation process (crotonobetaine hydration reaction and crotonobetaine reduction reaction), in the synthesis of acetyl-CoA/acetate (pyruvate dehydrogenase, acetyl-CoA synthetase [ACS] and ATP/acetate phosphotransferase) and in the distribution of metabolites for the tricarboxylic acid cycle (isocitrate dehydrogenase [ICDH]) and glyoxylate shunt (isocitrate lyase [ICL]) were followed in batch with resting cells both in the presence and absence of NaCl and in perturbation experiments performed on growing cells in a high density cell recycle membrane reactor. Further, the levels of carnitine, crotonobetaine, gamma-butyrobetaine and ATP and the NADH/NAD(+) ratio were measured in order to know how the metabolic state was modified and coenzyme pools redistributed as a result of NaCl's effect on the energy content of the cell. The results provided the first experimental evidence of the important role played by salt stress during resting and growing cell biotransformation (0.5 M NaCl increased the L-carnitine production in nearly 85%), and the need for high levels of ATP to maintain metabolite transport and biotransformation. Moreover, the main metabolic pathways and carbon flow operating during cell biotransformation was that controlled by the ICDH/ICL ratio, which decreased from 8.0 to 2.5, and the phosphotransferase/ACS ratio, which increased from 2.1 to 5.2, after a NaCl pulse fivefold the steady-state level. Resting E. coli cells were seen to be made up of heterogeneous populations consisting of several types of subpopulation (intact, depolarized, and permeabilized cells) differing in viability and metabolic activity as biotransformation run-time and the NaCl concentration increased. The results are discussed in relation with the general stress response of E. coli, which alters the NADH/NAD(+) ratio, ATP content, and central carbon enzyme activities.

The study of evolutionary relationships among human populations is fundamental to inferring processes that determine their structure and history. Among the different data types used to infer such relationships, molecular data, particularly nuclear and mitochondrial DNA, are preferred because of their high heritability and the low probability of changes during development. However, although the reliability of relatedness patterns based on other traits is discussed, except in unusual circumstances most prehistoric populations remain within the domain of morphological study. Therefore the primary goal of this study is to test the reliability of relatedness patterns constructed on the basis of craniometric data on a regional scale. In particular, we analyze samples from populations belonging to the Chaco, Pampa, and Patagonia regions of South America for which craniometric and molecular data are available. We compare a strongly supported relatedness pattern based on molecular data with the results obtained through landmark-based and semilandmark-based facial data. The matrices based on Euclidean distance for morphometric data and DA distances for molecular data were used to perform principal coordinates analyses and to obtain reticulograms. Finally, a principal components analysis of all individuals was performed with morphometric data. The results indicate that ordination analyses yield slightly different results depending on the morphometric data used. However, the reticulograms obtained with both landmark-based and semilandmark-based data allow the separation of the Chubut samples from the Chaco samples, with the Pampa sample in between the others; this pattern is congruent with molecular-based analyses. As a consequence, our results indicate that facial morphometric data allow the inference of the structure and history of the prehistoric populations for the studied region.

A thorough understanding of the in vivo kinetics of microorganisms requires the analysis of different data sets and therefore needs support from different sources of genome, transcriptome, proteome and metabolome data, as well as to generate new data in the laboratory to depict cell phenotypes in different scenarios. The value of dynamic metabolic data depends on the adequate design of wet experiments. In this paper a schematic representation of wet dynamic experiments to generate data is discussed. As a case study, the linking of the central metabolism with the carnitine secondary metabolism in E. coli is presented. The feed-back between the data generated and in silico modeling helps our understanding of the Escherichia coli expressed phenotype and permits new wet experiments to be designed to generate data concerning metabolic optimization.

Dental size and shape have been widely used to study biological relationships among human populations. Although several techniques have been proposed to quantify dental form, few attempts have been made to compare results obtained by application of different techniques. This work aims at comparing the information about size and shape of molar contours obtained from linear measurements, landmarks and semi-landmarks as well as evaluating the variation patterns among populations obtained by each method. The crowns of 35 permanent upper second molars belonging to archaeological samples from three regions of Argentina were analyzed. Buccolingual and mesiodistal crown diameters were measured and centroid size and crown index were used as size and shape descriptors, respectively. Likewise, four landmarks and 79 semi-landmarks were collected from the molar outline and relative warps (RW) analysis was performed on partial warps and uniform vectors; centroid size was estimated to summarize tooth size. The results indicate that size was consistently estimated by the three variable types. On the contrary, noticeable differences were found when the results of molar shape described by linear measurements were compared with those obtained using either landmarks or semi-landmarks. This study shows that considerable information about molar contour is added by using landmarks instead of crown diameters and that some morphological features, such as degree of cusp development, can only be captured by means of semi-landmark analysis. Finally, the interpretation of similarities among samples differs according to the selected description system.

Fueguian-Patagonian skulls have been characterized as some of the most robust of any modern crania. However, the causal factors of such robusticity remain unsettled. We assess within- and among-sample cranial robusticity of seven samples from continental Patagonia and Tierra del Fuego, using geometric morphometric techniques. In addition, the biomechanical, phylogenetic, and climatic hypotheses proposed to account for robusticity in such samples are discussed. Two Amerindian samples of farmers and two early middle Holocene samples from South America were included. The results show: 1) large variation in craniofacial robusticity among Patagonian samples, with the highest robusticity in samples from south continental Patagonia and Isla Grande of Tierra del Fuego, whereas central and north Patagonian samples display the same degree of robusticity as farmer samples; 2) that early middle Holocene samples display lower levels of robusticity than South Patagonian samples; and 3) strong association between latitude and craniofacial robusticity, with the most robust craniofacial morphologies occurring at the highest latitudes. In consequence, neither masticatory stress nor retention of ancestral features is supported by the morphological evidence analyzed. Hence it is hypothesized that endocrine changes related to cold climate may be a plausible explanation for several craniofacial features found in Fueguian and south continental Patagonian samples, such as their large masticatory component, and pronounced supraorbital ridge and glabellar region.

The aim of this work was to understand the steps controlling the biotransformation of trimethylammonium compounds into L(-)-carnitine by Escherichia coli. The high-cell density reactor steady-state levels of carbon source (glycerol), biotransformation substrate (crotonobetaine), acetate (anaerobiosis product) and fumarate (as an electron acceptor) were pulsed by increasing them fivefold. Following the pulse, the evolution of the enzyme activities involved in the biotransformation process of crotonobetaine into L(-)-carnitine (crotonobetaine hydration), in the synthesis of acetyl-CoA (ACS: acetyl-CoA synthetase and PTA: ATP: acetate phosphotransferase) and in the distribution of metabolites for the tricarboxylic acid (ICDH: isocitrate dehydrogenase) and glyoxylate (ICL: isocitrate lyase) cycles was monitored. In addition, the levels of carnitine, the cell ATP content and the NADH/NAD(+) ratio were measured in order to assess the importance and participation of these energetic coenzymes in the catabolic system. The results provided an experimental demonstration of the important role of the glyoxylate shunt during biotransformation and the need for high levels of ATP to maintain metabolite transport and biotransformation. Moreover, the results obtained for the NADH/NAD(+) pool indicated that it is correlated with the biotransformation process at the NAD(+) regeneration and ATP production level in anaerobiosis. More importantly, a linear correlation between the NADH/NAD(+) ratio and the levels of the ICDH and ICL (carbon and electron flows) and the PTA and ACS (acetate and ATP production and acetyl-CoA synthesis) activity levels was assessed. The main metabolic pathway operating during cell metabolic perturbation with a pulse of glycerol and acetate in the high-cell density membrane reactor was that related to ICDH and ICL, both regulating the carbon metabolism, together with PTA and ACS enzymes (regulating ATP production).

Over the last decade, geometric morphometric methods have been applied increasingly to the study of human form. When too few landmarks are available, outlines can be digitized as series of discrete points. The individual points must be slid along a tangential direction so as to remove tangential variation, because contours should be homologous from subject to subject whereas their individual points need not. This variation can be removed by minimizing either bending energy (BE) or Procrustes distance (D) with respect to a mean reference form. Because these two criteria make different assumptions, it becomes necessary to study how these differences modify the results obtained. We performed bootstrapped-based Goodall's F-test, Foote's measurement, principal component (PC) and discriminant function analyses on human molars and craniometric data to compare the results obtained by the two criteria. Results show that: (1) F-scores and P-values were similar for both criteria; (2) results of Foote's measurement show that both criteria yield different estimates of within- and between-sample variation; (3) there is low correlation between the first PC axes obtained by D and BE; (4) the percentage of correct classification is similar for BE and D, but the ordination of groups along discriminant scores differs between them. The differences between criteria can alter the results when morphological variation in the sample is small, as in the analysis of modern human populations.

Objective: To assess behavioral dependence using the Glover-Nilsson test and determine its association with successful smoking cessation., Material and Methods: An analytical longitudinal study was carried out, the target population of which consisted of smokers who enrolled in a smoking cessation clinic for treatment. The following variables were examined: age, sex, nicotine dependence (Fagerström test), psychoactive drug use, prior attempts at quitting, and behavioral dependence measured with the Glover-Nilsson test. The most recent version of this test is an 11-item questionnaire which classifies behavioral dependence according to the scores obtained: mild (<12), moderate (12-22), severe (23-33), and very severe (>33). Successful cessation was defined as self-reported abstinence confirmed by measurement of expired CO level (< or =10 ppm). Results were expressed as means (SD) for quantitative variables and percentages and absolute frequencies for qualitative variables., Results: The study population consisted of 167 smokers--89 men (53.3%) and 78 women (46.7%)--with a mean age of 43.5 (9.9) years, a nicotine dependence score (Fagerström test) of 6.5 (2.2) points, and a Glover-Nilsson score of 23.3 (6.6). Of the study population, 65.9% (n=110) had made previous attempts at quitting. Abstinence at 3 months was 55.1% (n=92). Differences between the sexes were found for age and previous attempts at quitting. Younger patients had higher scores on the Glover-Nilsson test and the Fagerström test and lower abstinence rates., Conclusions: Severe behavioral dependence can result in less successful cessation outcome. All aspects related to dependence must be assessed to help select the most adequate pharmacological and psychological treatment for results to be optimized.

The aim of this work was to understand the steps controlling the process of biotransformation of trimethylamonium compounds into L(-)-carnitine by Escherichia coli and the link between the central carbon or primary and the secondary metabolism expressed. Thus, the enzyme activities involved in the biotransformation process of crotonobetaine into L(-)-carnitine (crotonobetaine hydration reaction and crotonobetaine reduction reaction), in the synthesis of acetyl-CoA (pyruvate dehydrogenase, acetyl-CoA synthetase, and ATP:acetate phosphotransferase) and in the distribution of metabolites for the tricarboxylic acid (isocitrate dehydrogenase) and glyoxylate (isocitrate lyase) cycles, were followed in batch with both growing and resting cells and during continuous cell growth in stirred-tank and high-cell-density membrane reactors. In addition, the levels of carnitine, crotonobetaine, gamma-butyrobetaine, ATP, NADH/NAD(+), and acetyl-CoA/CoA ratios were measured to determine how metabolic fluxes were distributed in the catabolic system. The results provide the first experimental evidence demonstrating the important role of the glyoxylate shunt during biotransformation of resting cells and the need for high levels of ATP to maintain metabolite transport and biotransformation (2.1 to 16.0 mmol L cellular/mmol ATP L reactor h). Moreover, the results obtained for the pool of acetyl-CoA/CoA indicate that it also correlated with the biotransformation process. The main metabolic pathway operating during cell growth in the high cell-density membrane reactor was that related to isocitrate dehydrogenase (during start-up) and isocitrate lyase (during steady-state operation), together with phosphotransacetylase and acetyl-CoA synthetase. More importantly, the link between central carbon and L(-)-carnitine metabolism at the level of the ATP pool was also confirmed., (Copyright 2003 Wiley Periodicals, Inc.)

Objective: The patient orientation clinic (POC), acting as a filter, is an initiative aimed at reducing the waiting lists for medical specialities., Methods: For a six-months period, an internist and a registered nurse attended 1,265 patients proposed for those specialties., Results: 85.7% of cases were referred to their general practitioners after evaluation at our clinic. The remaining patients (14.3%) went on and frecuently benefited from initial therapies or because complementary tests and/or examinations were arranged for and earlier date., Conclusions: POC is shaping as a promising tool for health resource management in reducing waiting lists in medical specialties.

Recently we reported that neurotensin-SPDP-poly-L-lysine (NT-vector) is able to bind plasmid DNA (NT-polyplex) and polyfect cells expressing the high-affinity neurotensin receptor (NTRH) although with low transfecting efficiency: in vitro, 6.5+/-1.5%, and in vivo, 5+/-4%. In this work, we attempted to increase the transfecting efficiency by integrating the hemagglutinin HA2 fusogenic peptide and the Vp1 nuclear localization signal of SV40 to the NT-polyplex (fusogenic-karyophilic-NT-polyplex). Confocal microscopy and flow cytometry analysis showed that the fusogenic-karyophilic-NT-polyplex produced mostly nuclear localization of the plasmid DNA in NTRH-bearing N1E-115 cells. About 50% of N1E-115 cells internalized and expressed the reporter gene when the plasmid DNA was transferred by the fusogenic-karyophilic-NT-polyplex. Although to a less extent, the addition of each viral peptide separately to NT-polyplex (fusogenic-NT-polyplex or karyophilic-NT-polyplex) improved polyfection. Fusogenic-NT-polyplex produced 22.41+/-5.96% of internalization and 20.35+/-0.82% of expression in N1E-115 cells, whereas karyophilic-NT-polyplex yielded 13.75+/-3.88% and 10.94+/-2.04%, respectively. Basal internalization and expression were detected in N1E-115 cells in the presence of 100 nM SR-48692 and in NTRH-lacking cells. The fusogenic-karyophilic-NT-polyplex was microinjected into the substantia nigra to test its ability for gene transfer in vivo. Fusogenic-karyophilic-NT-polyplex internalization was observed within dopamine neurons only. Reporter gene expression was observed in a high proportion of dopamine neurons up to 60 days after NT-polyfection. Both internalization and expression were prevented by SR-48692. Our results show that the fusogenic-karyophilic-NT-polyplex is a highly efficient and specific gene vector and encourage its use to transfer gene of physiological interest to NTRH-bearing neurons., (Copyright 2002 Elsevier Science B.V.)

We present the case of a 33 year old man who consulted because a lumbago; a bone lesion was detected on a lumbosacral radiography, and finally was diagnosed of Multiple Myeloma. The illness, diagnosis and epidemiology are briefly analyzed, rebounding the rarity of its presentation in a young man.

Staphylococci are frequently isolated from human, animal and environmental samples. The genus Staphylococcus comprises 27 species, of which 23 are coagulase-negative. The pathogenic role of the coagulase-negative species remains to be fully established. Staphylococcus lugdunensis is a recently described coagulase-negative species. Its Latin name reflects the city (Lyon, France) where the bacteria was first described. The present study reports 7 cases of human infection caused by S. lugdunensis. Case 1: a 64 y/o diabetic woman in whom S. lugdunensis was isolated in the conjunctival exudate. Case 2: a 51 y/o male diagnosed of a bladder tumor, with S. lugdunensis detected in the purulent exudate of a transurethral resection. Case 3: an 81 y/o woman with cerebrovascular stroke, in whom S. lugdunensis was isolated from urine. Case 4: a 65 y/o male with bacterial endocarditis and S. lugdunensis isolation in blood culture. Case 5: a 79 y/o male with liver cirrhosis and S. lugdunensis in blood culture. Case 6: a 75 y/o female with cerebrovascular stroke, in whom S. lugdunensis was isolated from urine. Case 7: a 77 y/o male diagnosed of femoral osteosarcoma and isolation of S. lugdunensis in the purulent exudate of the wound. The present communication broadens the range of clinical syndromes in which coagulase-negative S. lugdunensis appears as pathogen.

Shear bond strength of a composite resin adhesive (Concise) and two resin-modified glass ionomer cements (Fuji Ortho LC and Geristore) bonded to porcelain surface was tested. Orthodontic brackets were bonded to 120 porcelain disks (Finesse) etched with 9% HF. Samples were divided into six groups: (1) Concise, (2) Concise/silane, (3) Geristore, (4) Geristore/silane, (5) Fuji, (6) Fuji/silane. No statistical difference in mean shear bond strength was found between silanated Concise (15.8 MPa), Geristore (19.4 MPa), and Fuji (18.5 MPa) groups, which were significantly higher than nonsilanated groups. Porcelain fracture was observed in all silanated groups and nonsilanated Geristore group. We conclude that (1) silane increases bond strength to porcelain significantly for composite resin and resin-modified glass ionomer cement, (2) Concise, Geristore, and Fuji Ortho LC provide comparable shear bond strength to porcelain.

Urinary infections caused by Staphylococcus are attributed usually to Staphylococcus epidermidis or Staphylococcus saprophyticus. 8 cases of urinary infection due to S. haemolyticus are discussed: 5 adults all of them over 66 years, diagnosed respectively of diabetes, cancer and stroke. Three children diagnosed of febrile syndrome, encephalopathy and enterocolitis associated with urinary infection. S. haemolyticus was identified through the determination of 19 biochemical parameters. The antibiograms performed showed that all S. haemolyticus isolated were sensible to vancomycin, nitrofurantoin and trimethoprim/sulfamethoxazole. It is concluded that S. haemolyticus is an opportunistic pathogen that is present on immunodepressed hosts, that is why is advisable to perform a more in-depth characterization of the S. epidermidis isolated in urine, especially in persistent pathologic processes.

A clinical case of a 58 year old male suffering from hepatitis non A, non B, and terminal chronic renal insufficiency under periodic dialysis, is presented. Following a 600 cc of packed red blood cells transfusion, there was an increase of antibodies IgG against cytomegalovirus (from 1/160 to 1/1560), detected by ELISA. At the same time, there were an increase of transaminases up to 404 UI/ml of GPT. Total bilirubin persisted normal. The possible etiology of the hepatitis non A, non B caused by cytomegalovirus is discussed and the results compared to those observed by other authors in immunosuppressed renal transplant patients.

We study 18 children with acute respiratory infection diagnosed early by direct immunofluorescence (DIF) using monoclonal antibodies to synticial respiratory virus (SRV). Antibodies to adenovirus, influenza virus A and B, parainfluenza virus 1, 2 and 3, mycoplasma, Q fever, herpes and cytomegalovirus (CMV) are also studied. We consider that in most cases the diagnosis of infections caused by SRV cannot be established by complement fixation, and should be accompanied by some antigen detection technique. Direct immunofluorescence facilitates the early detection of SRV in most cases before the appearance of antibodies to this virus. Only one of the 18 patients with positive DIF presented antibodies to SRV.

The author proposes to explore an event that received nationwide publicity through the Watergate investigation: the burglary of the office of a Los Angeles psychoanalyst believed to be treating Dr. Daniel Ellsberg. A brief questionnaire, with an accompanying letter, was mailed to all members of the American Psychoanalytic Association. It requested voluntary information on the reaction of their patients to the aforesaid particular event. The results of the study was then evaluated as serving hopefully an indirect inquiry into psychoanalytic practice. This paper is based on an adjusted sample of 861 respondent psychoanalysts, who reported on a total of 5,074 analysands. The resultant figures indicate that a high percentage of the analysand sample was silent concerning the office break-in during the eight-week period following the national publicity given the event. Of the small percentage of analysands that did present material concerning the event, the survey found that they were the patients of only 84 analysts of the entire sample of 861. The absence of reference to the Ellsberg Affair in so many patients may have been due to (1) the fact that analysts create an analytic situation which has a basic quality of interference such that events of this kind do not get communicated, and (2), more important, the fact that analysts through some defensive need failed to take cognizance of references to the Ellsberg Affair in dreams or in the latent content of the associations of their patients. A "natural" psychoanalytic experiment has been studied, and the results are offered for consideration.

Nine cases of respiratory infections caused by syncytial respiratory virus which were diagnosed by direct immunofluorescence with monoclonal antibodies are presented here. Six of them have been clinically diagnosed as bronchiolitis and the remaining three are diagnosed as obstructive bronchitis, upper respiratory cold and respiratory distress respectively. Seven are male and two are female. Their ages vary from 13 days to eleven months. Its usefulness is indicated given its speed and the current availability of specific antiviral therapeutics. The test would be especially indicated in atypical cases like nursing babies with apnea or those with congenital heart disease or other underlying lung diseases and also to prevent intrahospital epidemias. The conclusion is reached that direct immunofluorescence seems to be an attractive alternative for laboratories that do not have costly cell culture equipment.