Microbial Culture in Minimal Medium With Oil Favors Enrichment of Biosurfactant Producing Genes.

The waste produced by petrochemical industries has a significant environmental impact. Biotechnological approaches offer promising alternatives for waste treatment in a sustainable and environment-friendly manner. Microbial consortia potentially clean up the wastes through degradation of hydrocarbons using biosurfactants as adjuvants. In this work, microbial consortia were obtained from a production water (PW) sample from a Brazilian oil reservoir using enrichment and selection approaches in the presence of oil as carbon source. A consortium was obtained using Bushnell-Haas (BH) mineral medium with petroleum. In parallel, another consortium was obtained in yeast extract peptone dextrose (YPD)-rich medium and was subsequently compared to the BH mineral medium with petroleum. Metagenomic sequencing of these microbial communities showed that the BH consortium was less diverse and predominantly composed of Brevibacillus genus members, while the YPD consortium was taxonomically more diverse. Functional annotation revealed that the BH consortium was enriched with genes involved in biosurfactant synthesis, while the YPD consortium presented higher abundance of hydrocarbon degradation genes. The comparison of these two consortia against consortia available in public databases confirmed the enrichment of biosurfactant genes in the BH consortium. Functional assays showed that the BH consortium exhibits high cellular hydrophobicity and formation of stable emulsions, suggesting that oil uptake by microorganisms might be favored by biosurfactants. In contrast, the YPD consortium was more efficient than the BH consortium in reducing interfacial tension. Despite the genetic differences between the consortia, analysis by a gas chromatography-flame ionization detector showed few significant differences regarding the hydrocarbon degradation rates. Specifically, the YPD consortium presented higher degradation rates of C12 to C14 alkanes, while the BH consortium showed a significant increase in the degradation of some polycyclic aromatic hydrocarbons (PAHs). These data suggest that the enrichment of biosurfactant genes in the BH consortium could promote efficient hydrocarbon degradation, despite its lower taxonomical diversity compared to the consortium enriched in YPD medium. Together, these results showed that cultivation in a minimal medium supplemented with oil was an efficient strategy in selecting biosurfactant-producing microorganisms and highlighted the biotechnological potential of these bacterial consortia in waste treatment and bioremediation of impacted areas.

Upgrading end-of-line residues of the red seaweed Gelidium sesquipedale to polyhydroxyalkanoates using Halomonas boliviensis.

Agar extraction from Gelidium and Gracilaria red seaweed species produces hundred thousand ton of carbohydrate-rich residues annually. Gelidium sesquipedale waste biomass obtained after agar extraction, still contained 44.2 % w/w total carbohydrates (dry-weight basis). These residues were biologically up-graded to poly-3-hydroxybutyrate (P3HB) after saccharification of their carbohydrate fraction to simple sugars. A combined hydrolysis treatment using sulfamic acid followed by enzymatic hydrolysis with cellulases produced a glucose-rich hydrolysate with a negligible content of inhibitors. With this treatment a sugar yield of circa 30 % (g glucose/g biomass) was attained. The algal hydrolysates were assessed as carbon source for the production of P3HB by the halotolerant bacteria Halomonas boliviensis. A cell concentration of 8.3 g L-1 containing 41 % (w/w) of polymer and a yield (YP/S ) of 0.16 gpolymer/gglucose were attained in shake flask assays. In this work, cellulose-rich seaweed waste was shown to be an upgradable, sustainable source of carbohydrates.

Feeding strategies for tuning poly (3-hydroxybutyrate-co-4-hydroxybutyrate) monomeric composition and productivity using Burkholderia sacchari.

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-4HB)) co-polymers were produced at bench-scale in fed-batch cultivations by Burkholderia sacchari from glucose (main carbon-source) and gamma-butyrolactone (GBL) as co-substrate. As P(3HB-4HB) properties highly depend on the 4-hydroxybutyrate (4HB) molar fraction, it is advantageous to have a thorough knowledge of the process in order to promote the production of the targeted final product. In this work, polymers with a 4HB molar percentage ranging from 1.5 to 8.4% (mol/mol) were obtained as consequence of a fine tuning of the fed-batch operation conditions, namely regarding the co-substrate feeding rate and its addition time, as GBL is toxic to B. sacchari cells. The best results regarding both the 4HB incorporation (molar%) and the co-polymer productivity (7.1% and 1.1g/(L.h) respectively) were reached when a pulse of GBL (<10g/L) was added early in the accumulation phase followed by a constant GBL addition at a rate similar to that of consumption so that a steady co-substrate concentration in the medium was maintained.

Preventive effect of CuCl2 on behavioral alterations and mercury accumulation in central nervous system induced by HgCl2 in newborn rats.

This study investigated the benefits of Cu preexposition on Hg effects on behavioral tests, acetylcholinesterase (AChE) activity and Hg, and essential metal contents in the cerebrum and cerebellum of neonate rats. Wistar rats received (subcutaneous) saline or CuCl2 ·2H2O (6.9 mg/kg/day) when they were 3 to 7 days old and saline or HgCl2 (5.0 mg/kg/day) when they were 8 to 12 days old. Mercury exposure reduced the performance of rats in the negative geotaxis (3-13 days) and beaker test (17-20 days), inhibited cerebellum AChE activity (13 days), increased cerebrum and cerebellum Hg (13 days), cerebrum Cu (13 days), and cerebrum and cerebellum Zn levels (33 days). The performance of rats in the tail immersion and rotarod tests as well as Fe and Mg levels were not altered by treatments. Copper prevented all alterations induced by mercury. These results are important to open a new perspective of prevention and/or therapy for mercury exposure.

Polyhydroxyalkanoates: waste glycerol upgrade into electrospun fibrous scaffolds for stem cells culture.

This integrated study shows that waste glycerol can be bio-valorized by the fabrication of electrospun scaffolds for stem cells. Human mesenchymal stem cells (hMSC) provide an interesting model of regenerating cells because of their ability to differentiate into osteo-, chrondro-, adipo- and myogenic lineages. Moreover, hMSC have modulatory properties with potential on treatment of immunologic diseases. Electrospun fiber meshes offer tunable mechanical and physical properties that can mimic the structure of the native extracellular matrix, the natural environment where cells inhabit. Following a biorefinery approach, crude glycerol directly recovered from a biodiesel post-reaction stream was fed as major C source to Cupriavidus necator DSM 545 to produce polyhydroxyalkanoates at polymer titers of 9-25g/L. Two of the P(3HB-4HB-3HV) terpolymers produced, one containing 11.4% 4HB and 3.5% 3HV and the other containing 35.6% 4HB and 3.4% 3HV, were electrospun into fibers of average diameters of 600 and 1400nm, respectively. hMSC were cultured for 7 days in both fiber meshes, showing their ability to support stem cell growth at acceptable proliferation levels. Comparative results clearly demonstrate that scaffold topology is critical, with electrospun PHA fibers succeeding on the support of significant cell adhesion and proliferation, where planar PHA films failed.

From tissue iron retention to low systemic haemoglobin levels, new pathophysiological biomarkers of human abdominal aortic aneurysm.

Iron deposits are observed in tissue of abdominal aortic aneurysm (AAA) patients, although the underlying mechanisms are not completely elucidated. Therefore we explored circulating markers of iron metabolism in AAA patients, and tested if they could serve as biomarkers of AAA. Increased red blood cell (RBC)-borne iron retention and transferrin, transferrin receptor and ferritin expression was observed in AAA tissue compared to control aorta (immunohistochemistry and western blot). In contrast, decreased circulating iron, transferrin, mean corpuscular haemoglobin concentration (MCHC) and haemoglobin concentration, along with circulating RBC count, were observed in AAA patients (aortic diameter >3 cm, n=114) compared to controls (aortic diameter <3 cm, n=88) (ELISA), whereas hepcidin concentrations were increased in AAA subjects (MS/MS assay). Moreover, iron, transferrin and haemoglobin levels were negatively, and hepcidin positively, correlated with aortic diameter in AAA patients. The association of low haemoglobin with AAA presence or aortic diameter was independent of specific risk factors. Moreover, MCHC negatively correlated with thrombus area in another cohort of AAA patients (aortic diameter 3-5 cm, n=357). We found that anaemia was significantly more prevalent in AAA patients (aortic diameter >5 cm, n=8,912) compared to those in patients with atherosclerotic aorto-iliac occlusive disease (n=17,737) [adjusted odds ratio=1.77 (95% confidence interval: 1.61;1.93)]. Finally, the mortality risk among AAA patients with anaemia was increased by almost 30% [adjusted hazard ratio: 1.29 (95% confidence interval: 1.16;1.44)] as compared to AAA subjects without anaemia. In conclusion, local iron retention and altered iron recycling associated to high hepcidin and low transferrin systemic concentrations could lead to reduced circulating haemoglobin levels in AAA patients. Low haemoglobin levels are independently associated to AAA presence and clinical outcome.

On the heterogeneous composition of bacterial polyhydroxyalkanoate terpolymers.

Poly(3-hydroxybutyrate-4-hydroxybutyrate-3-hydroxyvalerate) (P(3HB-4HB-3HV)) terpolymers of low 3-hydroxyvalerate (3HV) content (1.7-6.4%) with 4-hydroxybutyrate (4HB) molar fractions from 1.8% to 35.6% were produced by fed-batch cultivation of Cupriavidus necator DSM545. Waste glycerol, γ-butyrolactone and propionic acid were used as main carbon source, 4HB and 3HV precursors, respectively. Uniaxial tensile tests were performed on the corresponding biopolymers. The Young's modulus and tensile strength of P(3HB-4HB-3HV) decreased, whereas the elongation at break increased with the 4HB molar%, following the general trend described for poly(3-hydroxybutyrate-4-hydroxybutyrate) (P(3HB-4HB)) but with pronounced lower elasticity. Differential scanning calorimetry results indicate that the temperature of crystallization and enthalpy of melting decreased as the 4HB% increased. No crystallization was observed in terpolymers containing more than 30% of heteromonomers (4HB and 3HV) even though multiple melting events were detected. Terpolymer fractions of different composition were obtained by solvent-fractionation of the original bacterial terpolymers.

Effect of cultivation parameters on the production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and poly(3-hydroxybutyrate-4-hydroxybutyrate-3-hydroxyvalerate) by Cupriavidus necator using waste glycerol.

Short-chain polyhydroxyalkanoate co-polymers (poly(3-hydroxybutyrate-co-4-hydroxybutyrate)) (P(3HB-co-4HB)) and terpolymers (poly(3-hydroxybutyrate-4-hydroxybutyrate-3-hydroxyvalerate)) (P(3HB-4HB-3HV)) were produced using high-cell density fed-batch cultures of Cupriavidus necator DSM 545. C-source for growth and 3HB synthesis was waste glycerol (GRP) from a biodiesel plant. Incorporation of 4HB monomers was promoted by γ-butyrolactone (GBL). Propionic acid (PA), a stimulator of 4HB accumulation, increased the 4HB molar ratio 2-fold, but also acted as 3HV precursor, yielding P(3HB-4HB-3HV). Dissolved oxygen (DOC) was a key parameter for % PHA accumulation and volumetric productivity (Prod(vol)). 4HB molar ratio increased in the presence of PA and with extended accumulation time. By manipulating DOC and cultivation time, P(3HB-4HB) with between 11.4 and 21.5 molar% of 4HB were attained. Similarly, P(3HB-4HB-3HV) was obtained with 4HB molar% between 24.8% and 43.6% and 3HV% from 5.6% to 9.8%. Mw varied between 5.5 × 10(5) and 1.37 × 10(6)Da. PHA production from GRP helps reducing production costs with concomitant GRP valorization.

Hemolytic-Uremic Syndrome in Uberlândia, MG, Brazil.

Purpose. To analyze the epidemiological, clinical, and laboratory characteristics of hemolytic-uremic syndrome (HUS) in Uberlandia, MG, Brazil. Methods. A historical cohort study was performed encompassing a ten-year period from January 1994 to January 2004 in the Department of Pediatric Nephrology at a full-service hospital; demographic factors, triggering factors, time of hospitalization, supportive therapy, and disease progression were analyzed. Results. Twenty-seven children aged 5 to 99 months (median age of 14 months) were studied; 70.4% were male. Of the 27 patients, 77.8% were from urban areas and 18.5% were from rural areas. Eight of the patients (29.6%) were reported to drink raw milk, and clinical diarrhea was reported in 81.5% of cases. The most common signs and symptoms were fever and vomiting (85.1%), anuria (63.0%), seizure (33.0%), cardiac involvement (11.0%), and acute pulmonary edema (7.4%). Dialysis was performed on 20 patients (74%). The mean hospital stay was 24 days (range: 13 to 36 days). While monitoring the patients, 2 died (7.4%), 3 developed chronic kidney disease (11.0%), and 21 (77.8%) developed hypertension. Conclusion. Our results emphasize the possibility of diagnosing HUS as a cause of renal failure in childhood in both typical (postdiarrheal) and atypical forms and suggest that an investigation of the etiological agent should be made whenever possible.

Efeito da época de colheita na produção de fitomassa e rendimento de óleo essencial de alecrim-pimenta (Lippia sidoides Cham. ) / Effect of harvesting time on phytomass production and essential oil yield in "alecrim-pimenta" (Lippia sidoides Cham. )

O objetivo do estudo foi avaliar a massa fresca, massa seca e rendimento de óleo essencial de Lippia sidoides cultivada no Norte de Minas. O delineamento foi em blocos ao acaso, com quatro tratamentos e cinco repetições. Os tratamentos foram constituídos por intervalos de colheita: 120, 180, 240, 300 e 360 dias após o transplantio. Em cada colheita, foram determinados a altura das plantas, o diâmetro da base do caule, o rendimento de matéria fresca de folhas, caule, parte aérea e o rendimento de matéria seca da parte aérea, além do teor e rendimento de óleo essencial por planta. O teor máximo de óleo essencial foi detectado aos 180 dias, enquanto que a produção máxima de matéria seca ocorreu aos 329 dias. A produção de óleo essencial por planta foi 2,34±1,15 g. A produtividade de óleo essencial foi de 124,8 kg ha-1, sendo recomendada a colheita aos 180 dias.

The aim of this study was to evaluate fresh and dry mass, as well as essential oil yield, in Lippia sidoides cultivated in the north of Minas Gerais State, Brazil. The experimental design was in randomized blocks, with five treatments and four replicates. Treatments consisted of the following harvesting intervals: 120, 180, 240, 300 and 360 days after transplanting. Measurements on each harvesting included plant height, stem base diameter, leaf, stem and shoot fresh matter yield, and shoot dry matter yield, besides essential oil content and yield per plant. The highest essential oil content was detected at 180 days, whereas the highest dry matter production was observed at 390 days. Essential oil yield per plant was 2.34±1.15 g and productivity was 124.8 kg ha-1. Thus, harvesting at 180 days is recommended.

Pressões respiratórias máximas: valores encontrados e preditos em indivíduos saudáveis / Maximal respiratory pressures: actual and predicted values in healthy subjects

OBJETIVO: Comparar os valores encontrados de pressões respiratórias máximas (pressão inspiratória máxima-PImáx e pressão expiratória máxima-PEmáx) em uma amostra de indivíduos saudáveis de Minas Gerais com valores preditos pelas equações propostas por Neder et al.³. MÉTODOS: Por meio de um manovacuômetro analógico, foram estudados 100 indivíduos saudáveis (54 mulheres, 46 homens), com idade entre 20-80 anos, recrutados no estado de Minas Gerais - Brasil. A análise estatística foi realizada com testes paramétricos ou não-paramétricos, dependendo da distribuição das variáveis, considerando significativo p< 0,05. RESULTADOS: PImáx em mulheres: a média dos valores encontrados foi significativamente menor que a média dos preditos (68,24 ± 29,48 x 86,53 ± 8,76; p= 0,000) e houve correlação de moderada magnitude e significativa (r= 0,557; p< 0,000); PImáx em homens: não houve diferença significativa entre os valores encontrados e preditos (104,67 ± 42,66 x 116,78 ± 14,02; p= 0,055) e houve correlação de baixa magnitude e não significativa (r= 0,236; p= 0,115); PEmáx em mulheres: não houve diferença significativa entre os valores encontrados e preditos (80,37 ± 33,32 x 85,88 ± 10,90; p= 0,164) e houve correlação de baixa magnitude e não significativa (r= 0,149; p= 0,283); PEmáx em homens: a média dos valores encontrados foi significativamente maior que a média dos preditos (142,28 ± 43,89 x 126,30 ± 14,19; p= 0,017) e houve correlação não significativa de baixa magnitude (r= 0,159; p= 0,290). CONCLUSÃO: Considerando que para haver concordância entre os valores encontrados e preditos é preciso não haver diferença e haver correlação entre os valores, as equações propostas por Neder et al.³ não foram capazes de predizer os valores de PImáx e PEmáx na população estudada.

OBJECTIVE: To compare actual values for maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) found in a sample of healthy individuals from the State of Minas Gerais (Brazil) with the values predicted from the equations put forward by Neder et al.³. METHOD: Using an analog manovacuometer, 100 healthy subjects (54 women and 46 men aged 20-80 years old) were studied. Statistical analysis was performed using parametric or non-parametric tests, depending on the distribution of the variables, and p< 0.05 was considered to be significant. RESULTS: For MIP in women, the mean of the actual values was significantly lower than the mean of the predicted values (68.24 ± 29.48 vs. 86.53 ± 8.76; p= 0.000) and there was a moderate and significant correlation (r= 0.557; p< 0.000). For MIP in men, no significant difference was observed between the actual and predicted values (104.67 ± 42.66 vs. 116.78 ± 14.02; p= 0.055) and there was a low and non-significant correlation (r= 0.236; p= 0.115). For MEP in women, there was no significant difference between the actual and predicted values (80.37 ± 33.32 vs. 85.88 ± 10.90; p= 0.164) and there was a low and non-significant correlation (r= 0.149; p= 0.283). For MEP in men, the mean of the actual values was significantly higher than the mean of the predicted values (142.28 ± 43.89 vs. 126.30 ± 14.19; p= 0.017) and there was a low and non-significant correlation (r= 0.159; p= 0.290). CONCLUSION: Considering that concordance between actual and predicted values requires the lack of difference and the existence of correlation between them, the equations proposed by Neder et al.³ were not successful in predicting MIP and MEP values in the population studied.

Relation of cervical length at 22-24 weeks of gestation to demographic characteristics and obstetric history

Preterm delivery is the main cause of neonatal death and ultrasonographic cervical assessment has been shown to be more accurate than digital examination in recognizing a short cervix. This is a cross-sectional study, involving 1131 women at 22-24 weeks of pregnancy, designed to determine the distribution of cervical length and to examine which variables of demographic characteristics and obstetric history increase the risk of a short cervix (15 mm or less). The distribution of maternal demographic and obstetric history characteristics among patients with cervical length ú15 mm was analyzed and compared to the findings for the general population. Risk ratios (RR) between subgroups were generated from this comparison. Median cervical length was 37 mm and in 1.5 percent of cases it was 15 mm or less. The proportion of women with a short cervix (<=15 mm) was significantly higher among patients with a low body mass index (RR = 3.5) and in those with previous fetal losses between 16-23 weeks (RR = 33.1) or spontaneous preterm deliveries between 24-32 weeks (RR = 14.1). We suggest that transvaginal sonographic measurement of cervical length be performed as part of a routine midtrimester ultrasound evaluation. There are specific variables of demographic characteristics and obstetric history which increase the risk of detecting a short cervix at 22-24 weeks.

Relation of cervical length at 22-24 weeks of gestation to demographic characteristics and obstetric history.

Preterm delivery is the main cause of neonatal death and ultrasonographic cervical assessment has been shown to be more accurate than digital examination in recognizing a short cervix. This is a cross-sectional study, involving 1131 women at 22-24 weeks of pregnancy, designed to determine the distribution of cervical length and to examine which variables of demographic characteristics and obstetric history increase the risk of a short cervix (15 mm or less). The distribution of maternal demographic and obstetric history characteristics among patients with cervical length pound 15 mm was analyzed and compared to the findings for the general population. Risk ratios (RR) between subgroups were generated from this comparison. Median cervical length was 37 mm and in 1.5% of cases it was 15 mm or less. The proportion of women with a short cervix (< or =15 mm) was significantly higher among patients with a low body mass index (RR = 3.5) and in those with previous fetal losses between 16-23 weeks (RR = 33.1) or spontaneous preterm deliveries between 24-32 weeks (RR = 14.1). We suggest that transvaginal sonographic measurement of cervical length be performed as part of a routine midtrimester ultrasound evaluation. There are specific variables of demographic characteristics and obstetric history which increase the risk of detecting a short cervix at 22-24 weeks.

Morphology and viability analysis of Streptomyces clavuligerus in industrial cultivation systems.

The effects of varying inoculum age and production scale upon the morphology and viability of Streptomyces clavuligerus were studied by analyzing visible and fluorescent light images acquired throughout pilot-plant and pre-industrial scale fermentations. Changes in production scale reveal that in 5 m(3) fermentors, the maximum hyphal area obtained is double the value obtained in 0.5 m(3) fermentors. It is probably due to the higher shear stresses acting upon hyphae in the 0.5 m(3) fermentor caused by higher tip speeds observed in these. The morphological quantification based on elongation and branching rates allowed fermentations to be pattern classified into distinct physiological time zones namely elongation, branching, fragmentation, etc. The general pattern observed for fermentations inoculated with late exponential phase inocula was similar to the pattern of fermentations run with stationary phase inocula except that both the elongation and branching periods started earlier in the former case. Using the available staining technique and image acquisition system, the viability seemed to be generally high and constant throughout the time course of all the studied fermentations.

Behaviour of Mycobacterium sp. NRRL B-3805 whole cells in aqueous, organic-aqueous and organic media studied by fluorescence microscopy.

The present work aimed at quantifying the viability and morphological changes occurring during the time course of the side-chain cleavage of beta-sitosterol, in aqueous, two-phase organic-aqueous and organic media by free resting cells of Mycobacterium sp. NRRL B-3805. The solvent used was bis(2-ethylhexyl) phthalate (BEHP). A 66.3% reduction in cell viability was observed after 24 h when the cells were incubated in phosphate buffer only, but the percentage of viable cells was constant thereafter. In biphasic systems with BEHP, cell viability was maintained at higher values in the first 48 h, during which complete degradation of substrate was achieved. The availability of oxygen, which should be higher in the biphasic system than in the aqueous system, and of a carbon and energy source, thus seem important for the cells to retain their viability. In biphasic systems, cells tended to shrink and decrease their surface roughness, i.e. to decrease their surface area, possibly as a way to protect themselves from mechanical stress due to the presence of organic-aqueous interfacial forces, which resulted in disaggregation of cell clusters. A method used to visualise BEHP droplets with a standard optical microscope showed that the cells adhered to the surface of the solvent droplets, but no cells were observed inside these. In pure BEHP medium, cells retained their viability level for at least 150 h, independently of a pre-incubation period, which did not seem to induce any adaptation effect. Solvent biocompatibility, higher oxygen availability and reduced interfacial stress could have contributed to this maintenance of viability.

Towards a cost effective strategy for cutinase production by a recombinant Saccharomyces cerevisiae: strain physiological aspects.

Although the physiology and metabolism of the growth of yeast strains has been extensively studied, many questions remain unanswered where the induced production of a recombinant protein is concerned. This work addresses the production of a Fusarium solani pisi cutinase by a recombinant Saccharomyces cerevisiae strain induced through the use of a galactose promoter. The strain is able to metabolise the inducer, galactose, which is a much more expensive carbon source than glucose. Both the transport of galactose into the cell-required for the induction of cutinase production-and galactose metabolism are highly repressed by glucose. Different fermentation strategies were tested and the culture behaviour was interpreted in view of the strain metabolism and physiology. A fed-batch fermentation with a mixed feed of glucose and galactose was carried out, during which simultaneous consumption of both hexoses was achieved, as long as the glucose concentration in the medium did not exceed 0.20 g/l. The costs, in terms of hexoses, incurred with this fermentation strategy were reduced to 23% of those resulting from a fermentation carried out using a more conventional strategy, namely a fed-batch fermentation with a feed of galactose.

Comparison between the Comfort and Hartwig sedation scales in pediatric patients undergoing mechanical lung ventilation.

CONTEXT: A high number of hospitalized children do not receive adequate sedation due to inadequate evaluation and use of such agents. With the increase in knowledge of sedation and analgesia in recent years, concern has also risen, such that it is now not acceptable that incorrect evaluations of the state of children's pain and anxiety are made. OBJECTIVE: A comparison between the Comfort and Hartwig sedation scales in pediatric patients undergoing mechanical lung ventilation. DESIGN: Prospective cohort study. SETTING: A pediatric intensive care unit with three beds at an urban teaching hospital. PATIENTS: Thirty simultaneous and independent observations were conducted by specialists on 18 patients studied. DIAGNOSTIC TEST: Comfort and Hartwig scales were applied, after 3 minutes of observation. MAIN MEASUREMENTS: Agreement rate (kappa). RESULTS: On the Comfort scale, the averages for adequately sedated, insufficiently sedated, and over-sedated were 20.28 (SD 2.78), 27.5 (SD 0.70), and 15.1 (SD 1.10), respectively, whereas on the Hartwig scale, the averages for adequately sedated, insufficiently sedated, and over-sedated were 16.35 (SD 0.77), 20.85 (SD 1.57), and 13.0 (SD 0.89), respectively. The observed agreement rate was 63% (p = 0.006) and the expected agreement rate was 44% with a Kappa coefficient of 0.345238 (z = 2.49). CONCLUSIONS: In our study there was no statistically significant difference whether the more complex Comfort scale was applied (8 physiological and behavioral parameters) or the less complex Hartwig scale (5 behavioral parameters) was applied to assess the sedation of mechanically ventilated pediatric patients.

Prenatal diagnosis of a benign facial tumor.

We report a case of prenatal diagnosis of a benign fetal skin tumor on the chin made at 27 weeks of pregnancy by ultrasound scan. We report this case given the uncommon diagnosis and the unique fetal facial profile seen on ultrasound, resembling the image of an ancient Egyptian pharaoh which made us call it 'Ramses' sign' as a future mnemonic aid to sonographers.

[Incipient cariogenic demineralization of human enamel]. / La desmineralización cariogénica incipiente en el esmalte humano.

32 teeth (12 premolars and 20 molars) were studied under light microscopy, polarized microscopy, transparence light microscopy and scanning electron microscopy. These teeth presented changes in colour in their free and proximal surface as well as close to pits and fissures. As an extra diagnostic test the PAS reaction was used to assess descalcifying processes in both light and transparence microscopy. Polarized light was used to assess normal enamel. Scanning electron microscopy corroborated the lesions produced in the enamel surface in the form of micropores. PAS reaction diagnosed decalcifying processes in yellow, brown and brownish stains. White staims not always were PAS-positive and when they reacted in the same manner as other positive stains, with the immersion technique. This penetrated 40-60 umtrs. and in some areas in relation to lamellae they reached dentin. Light, polarized and scanning electron microscopy showed the presence of micropores in the external surface of enamel in PAS-positive cases. The possibility of a modified PAS technique to use in clinical practice is discussed. It is concluded that PAS relation is useful as "ex situ" test to detect the first signs of mineral salt loss at the enamel surface. More research is needed to transfer these results to clinical practice.

[Experimental sialadenitis in castrated rats administered estrogens]. / Sialadenitis experimental en ratas castradas y aplicación de estrógenos.

Salivary glands are dependent on sexual hormones. The aim of the present work is to study the behavior of inflammatory response induced in animals that were castrated and injected with estrogens. Male adult wistar castrated rats (60-90 days) were used. A phlogogen pellet (zinc-oxide-turpentine essence) was placed between their sublingual and submaxillary glands and they were daily injected with 5 units of estrogen. The rats were killed after 8 and 12 days of treatment; submandibular pack was weighed, dissected and fixed in phormol Ph7 for its morphohistochemical study. Phlogogen pellet breaks out an acute inflammatory response that appears attenuated in castrated animals. Such character is enhanced when estrogens are used, disappearing ductal ectasis, becoming evident a granulation tissue of strange body in phagocytic activity and in contact with the pellet. As a consequence its follows that estrogen administration in castrated animals attenuates acute inflammatory response broken out by phlogogen pellet, determining characters with tendency to chronicity and giant cells differentiation of strange body.