As junções comunicantes são estruturas celulares que permitem o trânsito de moléculas entre as células, desempenhando funções de sinalização e transporte intercelular. São formadas por proteínas denominadas conexinas e representam estruturas-chave no funcionamento de tecidos altamente complexos e integrados, como o sistema nervoso central (SNC). O presente estudo avalia os efeitos da deleção da conexina 32 (Cx32) na inflamação e regeneração/cicatrização do SNC após 1, 3, 7, 10 e 20 dias pós-injeção intracerebral de brometo de etídio em camundongos deletados para Cx32 e camundongos normais. Para tanto, quantificou-se a expressão dos genes para fator de necrose tumoral alfa (TNFα), fator de crescimento transformador beta 1 (TGFβ), metaloproteinase 3 (MMP3), metaloproteinase 9 (MMP9) e inibidor tecidual de metaloproteinases 1 (TIMP1), através de PCR em tempo real. Os resultados indicam variáveis diferenças no padrão de expressão, incluindo variação na expressão de todos os genes pesquisados no período de 3 dias pós-injeção, ápice dos mecanismos de inflamação aguda. Estes resultados sugerem que a conexina 32 pode desempenhar funções importantes na sinalização molecular do processo inflamatório e regenerativo/cicatricial do sistema nervoso central. / Gap junctions are cellular structures that allow transit of molecules between cells, performing intercellular signaling and transportation. They are formed by proteins denominated connexins and represent key structures in highly complex and integrated tissues, such as the central nervous system (CNS). The present study evaluates the effects of connexin 32 (Cx32) deletion upon CNS inflammation and egeneration/cicatrization after 1, 3, 7, 10 and 20 days after intracerebral injection of ethidium bromide in Cx32 Knock Out and normal mice. To accomplish so, Real Time PCR gene expression quantification was performed uppon tumour necrosis factor alpha (TNFα), transforming growth factor beta 1 (TGFβ), metalloproteinase 3 (MMP3), metalloproteinase 9 (MMP9) and tissue inhibitor of metalloproteinases 1(TIMP1) genes. Results indicate variable differences in the expression pattern, including difference in expression of all evaluated genes in the 3 days after injection period, apex of the acute inflammation mechanisms. These results suggest that Cx32 may perform important functions on molecular inflammatory and regenerative/cicatrization signalling in the CNS.

This thesis presents an investigation of carbonyl sulphide as a new fumigant and related methodology studies. The first part involved the investigation of a new fumigant - carbonyl sulphide, which has the potential to replace methyl bromide. Its biological response or activity was investigated, e.g. toxicity to target organisms and phytotoxicity, environmental and worker safety considerations. In the second investigation, analytical methods were developed for the determination of fumigant movement through timber and fumigant residues in grains as well as a method of chemical fractionation to determine the fate of carbonyl sulphide. A comprehensive literature review of 161 references in these two areas is reported. Carbonyl sulphide was highly toxic to adults of three coleopteran species tested, namely Rhyzopertha dominica (F.), Tribolium confusum du Val, and Sitophilus oryzae (L.), the most sensitive species was R. dominica. For 6 hr exposure at 25�C, the L(CxT)95 value for R. dominica, S. oryzae and T. confusum were, respectively, 36.48, 99.82 and 113.0mg h L-1. Carbonyl sulphide inhibited 100% of mould in wet wheat and more than 90% of mould on dry wheat at lOOmg L-1. Both carbonyl sulphide and hydrogen cyanide were low in phytotoxicity without affecting germination of wheat, at levels needed to control insects. Unlike hydrogen cyanide, carbonyl sulphide can be used at minimum levels without decreasing plumule length of wheat. Chemical data on the sorption of carbonyl sulphide are compared with data from methyl bromide. The levels of carbonyl sulphide in the headspace of five commodities (wheat, barley, paddy, sorghum and peanut) and timbers (hardwood and softwood) decay more slowly than do levels of methyl bromide. Carbonyl sulphide was blown through a column of wheat as easily as was phosphine and more easily than was methyl bromide, and its front was blown out faster than phosphine and methyl bromide. Movement of two fumigants (methyl bromide and carbonyl sulphide) through, and sorption on, softwood and hardwood were studied. Each fumigant was sorbed less on softwood than on hardwood and penetrated softwood better than hardwood. Carbonyl sulphide penetrated timber better than did methyl bromide, and was less sorbed on timber. A rapid method of solvent extraction was developed to enable rapid estimation of the amount on intact fumigant sorbed in wood. This procedure enabled near quantitative recovery of methyl bromide as either intact fumigant or as bromide ion. Carbonyl sulphide residue in unfumigated wheat was found to be around 25- SOppb. Carbonyl sulphide left little residue on fumigated grains. Desorption of carbonyl sulphide from the wheat was extremely fast, 85% of it was released after one day aeration which was very much greater than that of methyl bromide and carbon disulphide. After 6 days aeration the incorporation of 14COS on mungbean, wheat, paddy, rice and safflower was lower than 7Oppb (calculated as COS equivalent). Food value or nutritional quality of foodstuffs is not harmed by carbonyl sulphide fumigation. This result was assessed by identifying any nonreversible change or combined residues in biochemical fractions of commodities including lipids, protein, amino acids, carbohydrate, etc., and no irreversible reaction between carbonyl sulphide and any constituent such as B vitamin, atocopherol, lysine, maltose and starch. Fumigants did not affect lipids, although each fumigant was applied to wheat at exaggerated concentrations, nor wheat germ oil and canola oil treated with extremely high concentration of fumigants. Factors which affect analysis of fumigants including stability of chemicals in extraction solvent and partitioning of fumigant between solvent and air, were examined. The partition ratio, defined as the fumigant concentration in extraction solvent to that in the headspace, varied with fumigant. Methods for multi-fumigant analysis were developed or modified and gave high recoveries and efficiency. The procedure of Daft of solvent extraction followed by partitioning was modified by being performed in sealed flasks. This raised the recovery of carbonyl sulphide, methyl bromide, phosphine and carbon disulphide. Recoveries were near quantitative at levels down to 6-16ppb (w/w) for tested fumigants. Thus the modified Daft method can be adapted to enable determination of the main fumigants used on staple foodstuffs. Microwave irradiation method give higher efficiency of removal of fumigants from grains. Limits of quantification were < 0.2ng g-1 (ppb w/w) for each tested fumigant. The detection limit of COS was calculated, as natural levels of the fumigant were detected in commodities. These are feasible, simple and rapid (< 2 min.) to be use to analyse fumigant residue in grains. Carbonyl sulphide has potential as a fumigant for grain and timber and may replace methyl bromide in some uses, subject to further investigation in commercial situations.

Layer-by-layer (LbL) assembly has proven to be a powerful technique for assembling thin films with a variety of properties including electrochromic, molecular sensing, oxygen barrier, and antimicrobial. LbL involves the deposition of alternating cationic and anionic ingredients from solution, utilizing the electrostatic charges to develop multilayer films. The present work incorporates cationic antimicrobial agents into the positively-charged layers of LbL assemblies. When these thin films are exposed to a humid environment, the antimicrobial molecules readily diffuse out and prevent bacterial growth. The influence of exposure time, testing temperature, secondary ingredients and number of bilayers on antimicrobial efficacy is evaluated here. Additionally, film growth and microstructure are analyzed to better understand the behavior of these films. The antimicrobial used here is a positively-charged quaternary ammonium molecule (e.g. cetyltrimethylammonium bromide [CTAB]) that allow assemblies to be made with or without an additional polycation like polydiallyldimethylamine. While films without this additional polymer are effective, they do not have the longevity or uniformity of films prepared with its addition. All of the recipes studied show linear growth as a function of the number of bilayers deposited and this growth is relatively thick (i.e. > 100 nm per bilayer). In general, 10-bilayer films prepared with CTAB and poly(acrylic acid) are able to achieve a 2.3 mm zone of inhibition against S. aureus bacteria and 1.3 mm against E. coli when test are conducted at body temperature (i.e. 37oC). Fewer bilayers reduces efficacy, but lower test temperatures improve zones of inhibition. As long as they are stored in a dry atmosphere, antimicrobial efficacy was found to persist even when films were used four weeks after being prepared. The best films remain effective (i.e. antimicrobially active) for 4-6 days of constant exposure to bacteria-swabbed plates. This technology holds promise for use in transparent wound bandages and temporary surface sterilization.

EVALUACIÓN DE SECUENCIA INVERSA CON VECURONIO EN PACIENTES SOMETIDOS A ANESTESIA GENERAL EN EL HOSPITAL GUILLERMO ALMENARA IRIGOYEN. Dr. Julio César Castillejo Correa Hospital Guillermo Almenara Irigoyen. UNMSM Objetivo: Determinar como influye la secuencia de administración de Vecuronio en el tiempo, para lograr condiciones adecuadas de intubación en pacientes que reciben anestesia general. Metodología: Se diseño un estudio Experimental (Ensayo clínico), Prospectivo, Analítico, Longitudinal, Tipo Cohorte. La muestra incluyó 200 pacientes, que cumplieron los criterios de inclusión y fueron divididos al azar en dos grupos: Grupo 1: Inducción de secuencia normal (Propofol - Vecuronio) Grupo 2: Inducción de secuencia inversa (Vecuronio - Propofol) Con ayuda de un observador quien registraba los datos de la monitorización y otro (el mismo en todos los casos) realizaba la intubación. Las condiciones de intubación fueron evaluadas mediante la escala de Damoal-Mehta modificada. La intubación endotraqueal se realizó de acuerdo a las condiciones clínicas del paciente monitorizado y en correlación a un estimulador de nervio periférico con acelerómetro (TOF- GUARD). Se utilizo el programa Epi - Info 2000. Resultados: Ambos grupos de estudio fueron comparables para edad, sexo, estado físico (ASA) y condiciones de intubación. La técnica de inducción con secuencia inversa (Vecuronio 0.15 mg/Kg durante 20 seg, 20 seg después se aplicó Propofol 2 mg/Kg durante 20 seg), es capaz de producir condiciones adecuadas de intubación en menor tiempo (28 seg promedio), en comparación con la secuencia normal de inducción (Propofol 2 mg/Kg durante 20 seg, 20 seg después se aplicó Vecuronio 0.15 mg/Kg durante 20 seg) que logró adecuadas condiciones de intubación en 101 seg promedio. Se apreció una reducción del tiempo de 73% al compararse ambas secuencias de inducción. Se dio el menor tiempo en lograr adecuadas condiciones de intubación (18 seg) en una paciente de sexo femenino, de 21 años y ASA I, que fue inducida con secuencia inversa. Se comprobó que con la técnica de secuencia inversa se dieron mínimas variaciones hemodinámicas (frecuencia cardiaca, presión arterial sistólica y diastólica). La medida de relajación muscular por neuroestimulador (TOF), corroboró que los pacientes del estudio sometidos a inducción con secuencia inversa (56.043%) y secuencia normal (58.86%), presentaron porcentajes semejantes de relajación, logrando el grupo de secuencia inversa menos tiempo para alcanzar estos valores. Las condiciones de intubación no mostraron diferencias significativas entre ambos grupos. Todos los pacientes tuvieron condiciones buenas y excelentes al momento de intubar. Conclusión: La inducción de secuencia inversa produce condiciones adecuadas de intubación en un menor tiempo, que la inducción con secuencia normal, resultando esta técnica eficiente en acortar el periodo entre la administración del agente de inducción y la intubación (Inicio de acción del relajante), observándose que al administrar la dosis completa de intubación del relajante muscular antes del inductor, se gana algunos segundos en el periodo en que el paciente permanece inconsciente y sin aislar la vía aérea. Palabras Clave: Secuencia Inversa, secuencia normal, TFIT / EVALUATION OF THE INVERSE SEQUENCE WITH VECURONIO IN PATIENTS SUBMITED TO GENERAL ANESTHESIA IN THE GUILLERMO ALMENARA IRIGOYEN´S HOSPITAL. Julio César Castillejo Correa Hospital NacionalGuillermo Almenara Irigoyen. UNMSM Objective: Determine how the administration sequence of Vecuronio influences in time, to reach suitable conditions for intubation in patients that receive general anesthesia. Methodology: A experimental study (clinical rehearsal), prospective, analític, longitudinal, Cohort type. The sample include 200 patients, that obeyed the inclusion criteria and they were divided at random in two groups: Group 1: normal- sequence Induction (Propofol - Vecuronio) Group 2: inverse- sequence Induction (Vecuronio - Propofol) With an observer's help that was registering the monitorization's data and another one (the same one in all cases) perform the intubation. The intubation conditions were evaluated with the Damoal's - Mehta scale modified. The endotraqueal intubation were realize according to the clinical conditions of the patient and in correlation to a peripheric- nerve stimulator with accelerometer (TOF - GUARD). We use Epi - Info 2000 program. Results: Both study groups were comparable for age, sex, physical state (ASA) and intubation conditions. The induction technique with inverse sequence (Vecuronio 0.15 mg/Kg during 20 sec, 20 sec after, Propofol applied 2 mg/Kg during 20 sec), is able to produce suitable intubation conditions in less time (28 sec average), as compared with the normal induction sequence (Propofol 2 mg/Kg during 20 sec, 20 sec after, Vecuronio applied 0.15 mg/Kg during 20 sec) that obtain suitable intubation conditions in 101sec average. A time reduction of 73% was appreciated when both sequences were compared. We obtain the less time in produce suitable intubation conditions (18 sec) in a patient of female sex, of 21 years, ASA I, that was induced with inverse sequence. We checked that with the inverse-sequence technique appears minimal hemodinamics variations (cardiac frequency, blood pressure sistolic and diastolic). The measure of the muscular relaxation by neuroestimulator (TOF), corroborated that the study's patients submit to induction with inverse sequence (56.043%) and normal sequence (58.86%), presented similar relaxation percentages, achieving the inverse-sequence group less time to reach these values. The intubation conditions not shows significant differences among both groups. All of the patients had good and excellent conditions at the moment of the intubation.. Conclusion: The inverse- sequence induction produces suitable conditions of intubation in a less time, than the induction with normal sequence, resulting this technique efficient in shortening the period among the administration of the agent of induction and the intubation (start of the relaxant's action), observing that when we administrate the complete intubation dose of the muscular relaxant before the inductor, the patient wins some seconds in the period whereon remain unconscious and without isolating airway. Key words: Inverse Sequence, normal sequence, TFIT

Acetylcholinesterase inhibition with pyridostigmine has been previously studied in patients with congestive heart failure (CHF), but the effects of this medication on heart rate recovery after exercise and other indices of parasympathetic activity in populations with greater baseline vagal tone has not been fully characterized. Ten healthy, sedentary adults and ten aerobically trained athletes were enrolled in a prospective, double blind, randomized placebo controlled crossover trial. All study subjects were treated with a single dose of oral pyridostigmine 30 mg and matching placebo on separate days. Heart rate variability (HRV) at rest and heart rate recovery (HRR) at one minute after maximal cardiopulmonary exercise stress testing were measured. In sedentary adults, pyridostigmine significantly lowered resting heart rate (mean (SEM) 58.1 (2.4) beats/min versus 66.7 (4.0) beats/min, p = 0.01), increased HRR at one minute (45.1 (2.8) beats/min versus 40.7 (3.4) beats/min, p = 0.02), and lowered both resting mean arterial pressure (80.3 (2.0) mm Hg versus 84.3 (2.7) mm Hg, p = 0.02) and peak exercise mean arterial pressure (103.3 (3.1) mm Hg versus 108.8 (3.2) mm Hg, p < 0.01). In trained athletes, resting heart rate and HRR at one minute were unaffected by pyridostigmine dosing, although a significant increase in VO2 max was observed with the study drug (54.8 (3.5) ml/kg/min versus 53.3 (3.6) ml/kg/min, p = 0.02). Pyridostigmine did not change indices of heart rate variability in either cohort. The difference in resting heart rate and HRR responses to pyridostigmine between athletes and sedentary controls likely reflects training induced modifications of the autonomic nervous system. The inability of acetylcholinesterase inhibition to affect HRV in either sedentary adults or athletes further suggests the improved HRR previously observed in CHF patients treated with pyridostigmine is secondary to parasympathetic augmentation.

The first project involved the evaluation of different times of application on the fertilizer nitrogen recovery (FNR) in the soil-plant system in an irrigated upland cotton system, during two seasons. This was accomplished by using the isotopic dilution technique applying the 15N to microplots. No differences were observed in the total plant FNR, seed and stover, soil and the total FNR among the different 15N application times; however, despite no differences were observed in the plant the FNR value ranged from 30-38%, while the seed exhibited the highest FNR with an average over 50% of the 15N recovered in the plant. In the soil, the obtained average FNR value was over 40% while the total FNR (plant + soil) ranged from 70-80%, being reduced as the 15N application time was delayed.The second project was conducted during two seasons to examine the 15N and bromide distribution pattern in the soil profile as a function of the time of application. 15Nitrogen and bromide were applied to the soil at three different times in a cotton growth cycle; after that, soil samples were taken at the end of the cotton cycle to a depth of 1.80 m., and 15N and bromide recoveries were determined. Slightly higher FNR were obtained with the intermediate application time. The higher FNR were detected in the surface layer (0-30 cm) with an average of 40%. Below 30 cm depth, low 15N recoveries were obtained and even lower below the 60 cm soil layer. Bromide recovery behavior was related to the water movement in the soil profile: as the Br- application time was delayed more of the anionic tracer was found in the top of the soil profile, while less Br- was found in the surface soil for the early Br- application time.

Lignin is a major chemical component of plants and the second most abundant natural polymer after cellulose. The concerns and interests of agriculture and industry have stimulated the study of genes governing lignin content in plants in an effort to adapt plants to human purposes. Arabidopsis thaliana provides a convenient model for the study of the genes governing lignin content because of its short growth cycle, small plant size, and small completely sequenced genome. In order to identify the genes controlling lignin content in Arabidopsis accessions using Quantitative Trait Locus (QTL) analysis, a rapid micro-scale method of lignin determination is required. The acetyl bromide method has been modified to enable the rapid micro-scale determination of lignin content in Arabidopsis. Modifications included the use of a micro-ball mill, adoption of a modified rapid method of extraction, use of an ice-bath to stabilize solutions and reduction in solution volumes. The modified method was shown to be accurate and precise with values in agreement with those determined by the conventional method. The extinction coefficient for Arabidopsis lignin, dissolved using acetyl bromide, was determined to be 23.35 g-iLcm-1. This value is independent of the Arabidopsis accession, environmental growth conditions and is insensitive to syringyl/guaiacyl ratio. The modified acetyl bromide method was shown to be well correlated with the 72% sulfuric acid method once the latter had been corrected for protein contamination and acid-soluble lignin content (R² = 0.988, P < 0.0001). As determined by the newly developed acetyl bromide method and confirmed by the sulfuric acid method, lignin content in Arabidopsis was found to be a divergent property. Lignin content in Arabidopsis was found to be weekly correlated with growth rate among Arabidopsis accessions (R² = 0.48, P = 0.011). Lignin content was also found to be correlated with plant height among Arabidopsis accessions (R² = 0.491, P < 0.0001).

There has been a great deal of interest in the use of LaBr3 (Ce) detectors for fast timing measurements. Due to their excellent energy resolution, ≈ 3% at 1MeV, they offer an improved signal to background over BaF2 which has ≈ 9% energy resolution. Many groups are planning arrays of LaBr3 detectors. The 8π collaboration has recently acquired a small array of 6 2”x 2” cylindrical LaBr3 detectors to replace its BaF2 detectors. We have been investigating the effects of detector-to-detector scattering on timing resolution. We have further investigated the use of Compton-suppression shields with LaBr3 detectors. This will also be the first testing of the DANTE acquisition system in the 8π. A summary of the results of our optimization, scattering studies, and Compton-suppression tests will be presented.

Lignin is a major chemical component of plants and the second most abundant natural polymer after cellulose. The concerns and interests of agriculture and industry have stimulated the study of genes governing lignin content in plants in an effort to adapt plants to human purposes. Arabidopsis thaliana provides a convenient model for the study of the genes governing lignin content because of its short growth cycle, small plant size, and small completely sequenced genome. In order to identify the genes controlling lignin content in Arabidopsis accessions using Quantitative Trait Locus (QTL) analysis, a rapid micro-scale method of lignin determination is required. The acetyl bromide method has been modified to enable the rapid micro-scale determination of lignin content in Arabidopsis. Modifications included the use of a micro-ball mill, adoption of a modified rapid method of extraction, use of an ice-bath to stabilize solutions and reduction in solution volumes. The modified method was shown to be accurate and precise with values in agreement with those determined by the conventional method. The extinction coefficient for Arabidopsis lignin, dissolved using acetyl bromide, was determined to be 23.35 g-iLcm-1. This value is independent of the Arabidopsis accession, environmental growth conditions and is insensitive to syringyl/guaiacyl ratio. The modified acetyl bromide method was shown to be well correlated with the 72% sulfuric acid method once the latter had been corrected for protein contamination and acid-soluble lignin content (R² = 0.988, P < 0.0001). As determined by the newly developed acetyl bromide method and confirmed by the sulfuric acid method, lignin content in Arabidopsis was found to be a divergent property. Lignin content in Arabidopsis was found to be weekly correlated with growth rate among Arabidopsis accessions (R² = 0.48, P = 0.011). Lignin content was also found to be correlated with plant height among Arabidopsis accessions (R² = 0.491, P < 0.0001).

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 4 uppsatser.