Using DNA barcoding to link cystacanths and adults of the acanthocephalan Corynosoma australe of the Southeastern Pacific Ocean (off Peru coast).

The objective of this study is to use DNA barcoding to link cystacanths and adults belonging to the acanthocephalans Corynosoma australe found in the Southeastern Pacific Ocean off the coast central from Peru. We sampled three species of commercial fish (Paralichthys adspersus (Steindachner), Paralabrax humeralis (Valenciennes), and Cheilodactylus variegatus (Valenciennes)) and two South American sea lions, Otaria byronia, stranded on the beaches of the city of Huacho and Barranca, Lima province. A total of 509 acanthocephalan larvae were found in the body cavity of 95 fish (prevalence 54.28%, total mean intensity 8.64). A total of 127 adult worms were found in the large intestine from two South American sea lions (P= 100%, MI= 63.5). A total of 203 larvae from P. humeralis were isolates (P=65.71%; MI= 8.83; MA=5.8), 235 (P=54.29%; MI= 12.37; MA= 6.71) from C. variegatus, and 71 (P=42.86%; MI= 4.73; MA= 2.03) from P. adspersus. All adult and larval specimens were morphologically identified as C. australe. They were generated cytochrome c oxidase subunit 1 (cox1) gene sequences of specimens and were compared with available data from GenBank. Molecular phylogenetic analysis supported our morphological identification, where the Peruvian isolates formed a clade with other isolates of C. australe from other countries of the American continent. Of the sequences obtained, two haplotypes were detected and were not identical with previous reports. Based on both DNA barcoding and morphological analyses, our finding represents the first molecular data of C. australe from Peru and the report of Cheilodactylus variegatus as a new paratenic host on the central coast, extending the knowledge and distribution range of this acanthocephalan in Southeastern Pacific Ocean.

Predictors of Remission and Low Disease Activity in Rheumatoid Arthritis Patients: Results From the Follow-up of a Real-World Peruvian Cohort.

BACKGROUND: Clinical remission is the goal in rheumatoid arthritis (RA) management; however, this can be difficult to achieve in several parts of the world. Our objective was to determine predictors of remission and remission/low disease activity (LDA) in RA. METHODS: A longitudinal real-setting RA cohort was followed up (January 2016-2020). Predictors examined were sex, age at diagnosis, disease duration, socioeconomic status, tobacco use, rheumatoid factor titer, comorbidities (Charlson index), Simple Disease Activity Index (SDAI) score, disability (Multidimensional Disease Health Assessment Questionnaire), health-related quality of life (Short Form-36 questionnaire), glucocorticoid dose, biological/target synthetic disease-modifying antirheumatic drugs, and conventional DMARD (c-DMARD) use. Univariable and multivariable generalized estimating equation models were done to determine predictors of remission (at a given visit) and sustained remission (2 consecutives visits), using the SDAI definition (0 or <3.3). Similarly, remission/LDA (SDAI <11) predictors were examined. RESULTS: Five hundred thirty RA patients included the following: 160 patients (30.2%) achieved remission in at least 1 visit, and 126 patients (23.77%) achieved sustained remission. On the multivariable analysis glucocorticoid dose (odds ratio [OR], 1.060; 95% confidence interval [CI], 1.027-1.094; p = 0.004) and current (OR, 2.293; 95% CI, 1.811-2.903; p < 0.001) or past (OR, 1.383; 95% CI, 1.127-1.698; p = 0.002) use of c-DMARDs predicted remission/LDA in at least 1 visit, whereas the SDAI (OR, 0.951; 95% CI, 0.942-0.959; p < 0.001), Multidimensional Disease Health Assessment Questionnaire (OR, 0.648; 95% CI, 0.549-0.764; p < 0.001), and age at diagnosis (OR, 0.994; 95% CI, 0.990-0.998; p = 0.004) were negative predictors. As to sustained remission/LDA, current (OR, 2.012; 95% CI, 1.458-2.776: p < 0.001) or past (OR, 1.517; 95% CI, 1.155-1.993; p = 0.003) use of c-DMARDs, having a better Short Form-36 questionnaire physical component summary (OR, 1.022; 95% CI, 1.014-1.029; p < 0.001), and older age at diagnosis (OR, 1.013; 95% CI, 1.003-1.022; p = 0.008) predicted it, whereas SDAI (OR, 0.949; 95% CI, 0.933-0.965; p < 0.001) and medium low/low socioeconomic status (OR, 0.674; 95% CI, 0.500-0.909; p = 0.010) were negative predictors. CONCLUSION: During follow-up of this real-world RA cohort, c-DMARD use predicted remission and remission/LDA. In contrast, disease activity was a negative predictor.

Differences in clinical manifestations and increased severity of systemic lupus erythematosus between two groups of Hispanics: European Caucasians versus Latin American mestizos (data from the RELESSER registry).

BACKGROUND: Systemic lupus erythematosus (SLE) is regarded as a prototype autoimmune disease because it can serve as a means for studying differences between ethnic minorities and sex. Traditionally, all Hispanics have been bracketed within the same ethnic group, but there are differences between Hispanics from Spain and those from Latin America, not to mention other Spanish-speaking populations. OBJECTIVES: This study aimed to determine the demographic and clinical characteristics, severity, activity, damage, mortality and co-morbidity of SLE in Hispanics belonging to the two ethnic groups resident in Spain, and to identify any differences. METHODS: This was an observational, multi-centre, retrospective study. The demographic and clinical variables of patients with SLE from 45 rheumatology units were collected. The study was conducted in accordance with Good Clinical Practice guidelines. Hispanic patients from the registry were divided into two groups: Spaniards or European Caucasians (EC) and Latin American mestizos (LAM). Comparative univariate and multivariate statistical analyses were carried out. RESULTS: A total of 3490 SLE patients were included, 90% of whom were female; 3305 (92%) EC and 185 (5%) LAM. LAM patients experienced their first lupus symptoms four years earlier than EC patients and were diagnosed and included in the registry younger, and their SLE was of a shorter duration. The time in months from the first SLE symptoms to diagnosis was longer in EC patients, as were the follow-up periods. LAM patients exhibited higher prevalence rates of myositis, haemolytic anaemia and nephritis, but there were no differences in histological type or serositis. Anti-Sm, anti-Ro and anti-RNP antibodies were more frequently found in LAM patients. LAM patients also had higher levels of disease activity, severity and hospital admissions. However, there were no differences in damage index, mortality or co-morbidity index. In the multivariate analysis, after adjusting for confounders, in several models the odds ratio (95% confidence interval) for a Katz severity index >3 in LAM patients was 1.45 (1.038-2.026; p = 0.02). This difference did not extend to activity levels (i.e. SLEDAI >3; 0.98 (0.30-1.66)). CONCLUSION: SLE in Hispanic EC patients showed clinical differences compared to Hispanic LAM patients. The latter more frequently suffered nephritis and higher severity indices. This study shows that where lupus is concerned, not all Hispanics are equal.

Prolactin levels are associated with a pro-inflammatory body mass distribution among women with systemic lupus erythematosus.

Objectives The objective of this study was to determine whether prolactin levels are associated with a pro-inflammatory body mass distribution in women with systemic lupus erythematosus (SLE). Methods This cross-sectional study was conducted in consecutive female SLE patients seen in our rheumatology department from January 2012 to July 2015. Prolactin was measured in ng/ml. Body mass distribution was measured by dual energy x-ray absorptiometry and it was divided into subtotal (whole body excluding the head), subtotal bone mineral content, lean mass index (appendicular lean mass/height2), subtotal trunk and leg fat percentages and trunk-to-leg fat ratio. The association between prolactin levels and body mass distribution components was evaluated by univariable and multivariable linear regression models adjusting for possible confounders. Results One hundred and eighty-five patients were evaluated; their mean (SD) age at diagnosis was 34.8 (13.8) years; nearly all patients were Mestizo. Patients included in this study were comparable to the rest of the cohort in terms of age, disease duration, SLEDAI, SDI and body mass index. Disease duration was 7.3 (6.6) years. The SLEDAI was 5.2 (4.3) and the SDI 0.9 (1.3). Prolactin levels were 18.9 (16.7) ng/ml. In univariable analyses, prolactin was negatively associated with bone mineral density, bone mineral content, leg fat percentage and lean mass index, and positively associated with trunk-to-leg fat ratio. In the multivariable analyses, prolactin was negatively associated with bone mineral content and positively associated with trunk-to-leg fat ratio. Conclusions Higher prolactin levels are associated with a pro-inflammatory body mass distribution in SLE patients.

Circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive T cells are independently associated with disease damage in systemic lupus erythematosus patients.

OBJECTIVE: To determine whether circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive (DP) T cells are independently associated with damage accrual in systemic lupus erythematosus (SLE) patients. METHODS: This cross-sectional study was conducted between September 2013 and April 2014 in consecutive SLE patients from our Rheumatology Department. CD4+CD28null and CD4+CD8+ DP T-cell frequencies were analyzed by flow-cytometry. The association of damage (SLICC/ACR Damage Index, SDI) and CD4+CD28null and CD4+CD8+ DP T cells was examined by univariable and multivariable Poisson regression models, adjusting for possible confounders. All analyses were performed using SPSS 21.0. RESULTS: Patients' (n = 133) mean (SD) age at diagnosis was 35.5 (16.8) years, 124 (93.2%) were female; all were mestizo (mixed Caucasian and Amerindian ancestry). Disease duration was 7.4 (6.8) years. The SLE Disease Activity Index was 5.5 (4.2), and the SDI 0.9 (1.2). The percentages of CD4+CD28null and CD4+CD8+ DP T cells were 17.1 (14.4) and 0.4 (1.4), respectively. The percentage of CD4+CD28null and CD4+CD8+ DP T cells were positively associated with a higher SDI in both univariable (rate ratio (RR) 1.02, 95% confidence interval (CI): 1.01-1.03 and 1.17, 95% CI: 1.07-1.27, respectively; p < 0.001 for both) and multivariable analyses RR 1.02, 95% CI: 1.01-1.03, p = 0.001 for CD4+CD28null T cells and 1.28, 95% CI: 1.13-1.44, p < 0.001 for CD4+CD8+ DP T cells). Only the renal domain remained associated with CD4+CD28null in multivariable analyses (RR 1.023 (1.002-1.045); p = 0.034). CONCLUSIONS: In SLE patients, CD4+CD28null and CD4+CD8+ DP T cells are independently associated with disease damage. Longitudinal studies are warranted to determine the predictive value of these associations.

Effects provoked by chronic undernourishment on the fibre type composition and contractility of fast muscles in male and female developing rats.

In this study, we compare the effects of pre- and post-natal food deprivation on the relative proportion of fibre types and contractile responses in the extensor digitorum longus (EDL) muscle of female and male rats at different post-natal ages. EDL muscles from undernourished male (UM) rats showed a higher proportion of Type IIB than IIA fibres and larger normalized twitch responses (with respect to muscle weight) than those of controls (CM). In contrast, EDL muscles from control (CF) and undernourished female rats (UF) showed no significant differences in their fibre type composition and normalized twitch forces at most of the ages analysed. Our data are indicative that the EDL muscles from undernourished males are more susceptible to the effects exerted by low food income than the EDL muscles from female rats. It is proposed that changes in the reactive oxygen species (ROS) concentration and hormonal factors, due to undernutrition, are involved in the alterations observed in the fibre type composition and force production of EDL muscles in undernourished male rats and that estrogens may have an antioxidant protective role on the undernourished EDL muscles in female rats.

High prolactin levels are independently associated with damage accrual in systemic lupus erythematosus patients.

OBJECTIVE: to determine whether prolactin levels are independently associated with disease damage in systemic lupus erythematosus (SLE) patients. METHODS: these cross-sectional analyses were conducted in SLE patient members of the Almenara Lupus Cohort who were seen between January 2012 and June 2013. Disease damage was ascertained with the System Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index (SDI). Prolactin was measured in ng/ml. The association between prolactin levels and the SDI (total and its domains) was evaluated using Spearman's correlation. Subsequently, adjusted Poisson regression models were performed to evaluate these associations. RESULTS: 160 patients were included. 147 (91.9%) were female; their median age at diagnosis was 33.4 (interquartile range (IQR): 26.0-44.3) years; their disease duration was 5.5 (IQR: 2.6-9.7) years. The median prolactin value was 16.8 (IQR: 11.8-24.5) ng/ml. After adjusting for confounders in the Poisson regression model the estimated rate ratios (RR) and 95% confidence interval (CI) for each 10 ng/ml increment of prolactin were 1.13 (95% CI 1.60-1.20, p<0.001) for the total SDI score, 1.15 (1.03-1.28, p=0.003) for the renal domain and 1.41 (1.11-1.79, p=0.003) for the cardiac/peripheral vascular domains. CONCLUSIONS: there was a positive association between prolactin levels and the SDI (overall and its renal and cardiac/peripheral vascular domains), independently of other well-known risk factors.

Multicenter longitudinal study of B-lymphocyte depletion in refractory systemic lupus erythematosus: the LESIMAB study.

OBJECTIVE: This study aimed to investigate the effectiveness and safety of single and repeated courses of rituximab in patients with refractory lupus. METHODS: LESIMAB is a multicenter, retrospective, longitudinal study of lupus patients who have not responded to standard therapy and have been treated with rituximab. Response rates at six months and at follow-up were defined as efficacy outcomes. Complete response was defined as a SELENA-SLEDAI score ≤ two and a SELENA-SLEDAI Flare Index of zero. Partial response was defined as a reduction in the SELENA-SLEDAI score of ≥four points with no new or worsening of symptoms. Adverse events were collected. RESULTS: Seventy-three (62.9%) of 116 patients achieved a response at six months (complete in 22 and partial in 51). Ninety-seven (77.6%) of 128 patients achieved a response after a mean follow-up of 20.0 ± 15.2 months (complete in 50 and partial in 47). High baseline SLEDAI score, previous treatment with ≥100 mg/day prednisone, and no history of severe hematologic flare were associated with response after the first treatment course. The median time to response was 6.5 months (95% CI, 5.0-8.0). Thirty-seven patients (38.1%) relapsed after the first infusion. The flare was severe in seven cases and mild to moderate in 29 cases. Serious infection rate was 12.6/100 patient-years. A schedule of four weekly doses was associated with more serious infections. Six patients died: two of infection and four of lupus complications. CONCLUSION: Rituximab can be an effective treatment option for patients who have refractory lupus with severe or life-threatening disease with an acceptable tolerance profile.

Geographical structuring of Trypanosoma cruzi populations from Chilean Triatoma infestans triatomines and their genetic relationship with other Latino American counterparts.

In order to obtain more information about the population structure of Chilean Trypanosoma cruzi, and their genetic relationship with other Latino American counterparts, we performed the study of T. cruzi samples detected in the midgut content of Triatoma infestans insects from three endemic regions of Chile. The genetic characteristics of these samples were analysed using microsatellite markers and PCR conditions that allow the detection of predominant T. cruzi clones directly in triatomine midgut content. Population genetic analyses using the Fisher's exact method, analysis of molecular variance (AMOVA) and the determination of F(ST) showed that the northern T. cruzi population sample was genetically differentiated from the two southern population counterparts. Further analysis showed that the cause of this genetic differentiation was the asymmetrical distribution of TcIII T. cruzi predominant clones. Considering all triatomines from the three regions, the most frequent predominant lineages were TcIII (38%), followed by TcI (34%) and hybrid (8%). No TcII lineage was observed along the predominant T. cruzi clones. The best phylogenetic reconstruction using the shared allelic genetic distance was concordant with the population genetic analysis and tree topology previously described studying foreign samples. The correlation studies showed that the lineage TcIII from the III region was genetically differentiated from the other two, and this differentiation was correlated with geographical distance including Chilean and mainly Brazilian samples. It will be interesting to investigate whether this geographical structure may be related with different clinical manifestation of Chagas disease.

Molecular identification and epidemiological data of Anisakis spp. (Nematoda: Anisakidae) larvae from Southeastern Pacific Ocean off Peru.

The objective of this study is to determine the infection status of nematode larvae and record epidemiological molecular data in commercial fish from the southeast Pacific off the central coast of Peru. Anisakiasis is a fish-borne zoonosis caused by Anisakis larvae, parasites of relevance in the fishery resources that have negative impact on public health. Between January 2012 to December 2014, 345 specimens of four fish species (Trachurus symmetricus murphyi, Scomber japonicus peruanus, Merluccius gayi peruanus and Seriolella violacea) were examined for Anisakis sp. larvae. A total of 997 Anisakis sp. larvae were found in the body cavity of 196 fish (total prevalence 53.7%, total mean intensity 5.08). After morphological analysis, 958 (96.08%) larvae were identified as Type I and 39 (3.92%) as Type II. Specimens were identified by molecular analysis of the mitochondrial cytochrome c oxidase subunit II (cox2) gene, confirming that A. pegreffii is the predominant species and the most important agent of human anisakiasis off the Peru Central Coast. In addition, we revealed the occurrence of A. physeteris (s.l.) in S. japonicus peruanus (P = 18.0%; MI = 2.17). Therefore, the results obtained in the present study improve the knowledge of the occurrence of Anisakis species in the commercial fish from the Southeastern Pacific Ocean, highlighting the importance of considering a potential hazard for humans and the necessity of further research in other fishes of greater preference by the Peruvian population.

Toxicidad del hipoclorito de sodio y compuestos de amonio cuaternario en seres humanos. Una revisión sistemática en época de COVID-19 / Toxicity of sodium hypochlorite and quaternary ammonium compounds in humans. A systematic review in the time of COVID-19

Los desinfectantes son productos que se utilizan de manera cotidiana, su uso se ha incrementado debido a los cambios en los hábitos de bioseguridad que incorporó la población desde el inicio de la pandemia por la COVID-19; en similar medida, han aumentado las intoxicaciones por la exposición a estas sustancias. Conocer los mecanismos a través de los cuales los productos de desinfección pueden causar una intoxicación es importante para desarrollar estrategias de prevención y manejo oportuno. Con este fin, se revisó la información de artículos científicos y reportes de caso, mediante la búsqueda sistemática en línea en PubMed, Medline, Google Scholar y EBSCO, relacionada a intoxicaciones con compuestos de amonio cuaternario e hipoclorito de sodio. El procedimiento utilizado implicó la búsqueda de palabras claves alusivas al tema mediante el uso de Descriptores en Ciencias en Salud y Medical Subject Headings, posteriormente se utilizó metodología “Preferred Reporting Items for Systematic reviews and Meta-Analyses”. Los resultados del estudio evidenciaron que el hipoclorito de sodio afecta a las células y tejidos, mediante sus propiedades oxidativas, provocando alteración de la membrana citoplasmática, desnaturalización y formación de agregados en las proteínas, daño al ADN e inflamación asociada a la lisis celular. Por otro lado, los compuestos de amonio cuaternario afectan principalmente a la membrana celular, ocasionando daño inflamatorio, fibrosis y alteraciones reproductivas. Los dos compuestos afectan la integridad de la célula de manera directa. Sin embargo, sus efectos se ven exacerbados por los cambios que ocurren en el entorno celular. (AU)

Disinfectants are products that are used on a daily basis, their use has increased due to changes in biosafety habits that the population has adopted since the beginning of COVID19. To a similar extent, poisoning from exposure to these substances has increased. Consequently, knowing the mechanisms through which disinfection products can cause poisoning is important to develop prevention strategies and timely management. To this end, the information related to poisoning with quaternary ammonium compounds and sodium hypochlorite was reviewed in scientific articles and study cases by a systematic online search in PubMed, Medline, Google Scholar and EBSCO. The procedure used involved the search for keywords alluding to the topic by using Descriptors in Health Sciences and Medical Subject Headings. Later the «Preferred Reporting Items for Systematic reviews and Meta-Analyses» methodology was used. The results of the study showed that sodium hypochlorite affects cells and tissues through its oxidative properties, causing alteration of the cytoplasmic membrane, denaturation and formation of protein aggregates, DNA damage and inflammation associated with cell lysis. On the other hand, quaternary ammonium compounds mainly affect the cell membrane, causing inflammatory damage, fibrosis and reproductive disorders. Both compounds directly affect the integrity of the cell. However, its effects are exacerbated by changes that occur in the cellular environment. (AU)

Selective oxidative dehydrogenation of propane to propene using boron nitride catalysts.

The exothermic oxidative dehydrogenation of propane reaction to generate propene has the potential to be a game-changing technology in the chemical industry. However, even after decades of research, selectivity to propene remains too low to be commercially attractive because of overoxidation of propene to thermodynamically favored CO2 Here, we report that hexagonal boron nitride and boron nitride nanotubes exhibit unique and hitherto unanticipated catalytic properties, resulting in great selectivity to olefins. As an example, at 14% propane conversion, we obtain selectivity of 79% propene and 12% ethene, another desired alkene. Based on catalytic experiments, spectroscopic insights, and ab initio modeling, we put forward a mechanistic hypothesis in which oxygen-terminated armchair boron nitride edges are proposed to be the catalytic active sites.

[Seminal vesicle cysts and infertility in autosomal dominant polycystic kidney disease]. / Quistes de las vesículas seminales e infertilidad en la poliquistosis renal autosómica dominante.

Autosomal dominant polycystic kidney disease (ADPKD) is a systemic hereditary disorder characterized by bilateral diffuse renal cysts. Extrarenal involvement is a well known manifestation of ADPKD. Cysts in the liver, pancreas, lung, spleen, oesophagus, ovary, testis, epididymis, prostate, thyroid, bladder, uterus, brain, paraespinal, and seminal vesicle have also been described. The occurrence of seminal vesicle cysts is often unrecognised. We report here a man with seminal vesicle cysts and azoospermia associated with ADPKD. Seminal vesicle cysts are not uncommon in ADPKD and in some cases it is associated with infertility. Ultrasound and computed tomography imaging were effective in documenting the underlying lesions non-invasively. Studies evaluating fertility in patients with seminal vesicle cysts and ADPKD are needed.

[Chronic renal failure secondary to uterine prolapse]. / Insuficiencia renal crónica secundaria a prolapso uterino.

Acute and chronic renal failure secondary to bilateral severe hydroureteronephrosis is a rare sequela of uterine prolapse. We report a case of neglected complete uterine prolapse in a 72-year-old patient resulting in bilateral hydroureter, hydronephrosis, and chronic renal failure. In an attempt to diminish the ureteral obstruction a vaginal pessary was used to reduce the uterine prolapse. Finally, surgical repair of prolapse by means of a vaginal hysterectomy was performed. In conclusion, all patients presenting with complete uterine prolapse should be screened to exclude urinary tract obstruction. If present, obstructive uropathy should be relieved by the reduction or repair of the prolapse before irreversible renal damage occurs.

Monitoring the efficacy of specific treatment in chronic Chagas disease by polymerase chain reaction and flow cytometry analysis.

PCR and FC-ALTA were used to monitor parasite clearance in 54 chronic chagasic patients who had completed therapy with allopurinol (ALLO, n = 31) or itraconazole (ITRA, n = 23) ten years earlier. All patients maintained positive conventional serology. 25 of them showed positive XD (ALLO, n = 11 and ITRA, n = 14) and 29 negative XD (ALLO, n = 20 and ITRA, n = 9). 43 patients were positive by both techniques (ALLO, n = 23 and ITRA, n = 20). Seven of 54 patients were negative by PCR and positive by FC-ALTA and three of 54 were positive by PCR and negative by FC-ALTA. Only one case with both tests negative should be considered cured. Of 29 patients with negative XD, 14 treated ALLO (70 %) and nine with ITRA (77.8 %) showed positive PCR and FC-ALTA. These results do not show differences of efficacy among the drugs, and reinforce the relevance of using sensitive tools such as PCR and FC-ALTA for the follow-up of patients with chronic Chagas disease.

Purification and characterization of a beta-like DNA polymerase from Trypanosoma cruzi.

A DNA polymerase was purified to near homogeneity from Trypanosoma cruzi epimastigotes. This preparation had a major polypeptide of 50 kDa and a minor band of 45 kDa. SDS-PAGE studies and a novel colorimetric activity gel technique demonstrated that the 50-kDa polypeptide chain is the catalytic subunit of this T. cruzi DNA polymerase. Western blot analysis of different purification stage fractions strongly suggests that this 50-kDa protein is the intact catalytic subunit and does not correspond to a degradation product from a larger one. This T. cruzi DNA polymerase is insensitive to aphidicolin, butylphenyldeoxyguanosine triphosphate, berenil, ethidium bromide and N-ethylmaleimide, but is markedly inhibited by the dideoxythymidine triphosphate analogue. Studies with different DNA templates showed that the DNA polymerase prefers activated DNA as substrate and that it cannot elongate oligoriboadenylate primers. The data presented in this paper are consistent with the hypothesis that this enzyme corresponds to a beta-like DNA polymerase present in the parasitic protozoon T. cruzi.

Conserved organization of genes in trypanosomatids.

Trypanosomatids are unicellular protozoan parasites which constitute some of the most primitive eukaryotes. Leishmania spp, Trypanosoma cruzi and members of the Trypanosoma brucei group, which cause human diseases, are the most studied representatives of this large family. Here we report a comparative analysis of a large genomic region containing glucose transporter genes in three Salivarian trypanosomes (T. brucei, T. congolense and T. vivax), T. cruzi and Leishmania donovani. In T. brucei, the 8 kb (upstream) and 14 kb (downstream) regions flanking the glucose transporter genes cluster contain two and six new genes, respectively, six of them encoding proteins homologous to known eukaryotic proteins (phosphatidylinositol 3 kinase, ribosomal protein S12, DNAJ and three small G-proteins--Rab1, YPT6 and ARL3). This gene organization is identical in T. brucei, T. congolense and T. vivax suggesting that Salivarian trypanosomes have a high level of conservation in gene organization. In T. cruzi and Leishmania, the overall organization of this cluster is conserved, with insertion of additional genes when compared with T. brucei. Phylogenetic reconstitution based on glucose transporters is in accord with the monophyly of the genus Trypanosoma and the early separation of T. vivax within Salivarian trypanosomes. On the basis of gene organization, biochemical characteristics of isoforms and phylogeny, we discuss the genesis of the glucose transporter multigene family in Salivarian trypanosomes.

Evidence of absence of Trypanosoma cruzi kinetoplast DNA methylation by restriction endonuclease analysis.

Eight kinetoplast DNA samples from very different T. cruzi zymodemes were digested with the isoschizomer group of enzymes (MspI-HpaII) and (MboI-Sau 3AI), able to detect DNA methylation on cytidine and adenine for the CCGG and GATC sequences, respectively. Restriction digestion analysis of each kDNA with both isoschizomer groups of enzymes did not display a different profile suggesting that maxicircles and minicircles on this trypanosomatid are not methylated.

Effects of nebulized salbutamol on respiratory mechanics in adult respiratory distress syndrome.

OBJECTIVE: To determine whether nebulized salbutamol improves the respiratory mechanics of patients with adult respiratory distress syndrome (ARDS). We also assessed the mechanisms that contribute to high respiratory system resistances during this disease. PATIENTS AND SETTING: Eleven consecutive patients with ARDS without clinical evidence of chronic obstructive pulmonary disease, admitted to a polivalent intensive care unit, and mechanically ventilated with Siemens Elema Servo C ventilator at constant inspiratory flow. METHOD: Peak airway pressure (Ppeak), airway pressure immediately after end inspiratory occlusion (P1), plateau pressure (P2) and intrinsic positive end-expiratory pressure (PEEPi) were measured at baseline condition and then 5, 15, and 30 min after 1 mg of salbutamol had been administered via a nebulizer through the endotracheal tube. Partial pressure of arterial oxygen (PaO2), heart rate (HR) and mean blood pressure (BP) were monitored and minimal respiratory system resistances (Rrs, m), additional resistances (DRrs) and static compliance (Cst) were computed. RESULTS: Between baseline and post-salbutamol, we observed changes in Ppeak, P1, P2, PEEPi and Rrs, m. As there were no significant differences between values at the different intervals during post administration, the results are described comparing baseline and 15 min post-salbutamol administration values. We found a significant decrease in Ppeak (4.9 +/- 0.8 cmH2O). P1 (3 +/- 0.6 cmH2O). P2 (2.1 +/- 0.6 cmH2O), PEEPi (1.9 +/- 0.5 cmH2O) and Rrs, m (1.9 +/- 0.3 cmH2O/1 s-1); DR, rs decreased in five patients, did not change in four and increased in two. HR, PaO2 and BP did not change. CONCLUSIONS: a) Salbutamol administered through the endotracheal tube by a nebulizer device lessens respiratory system resistances and airway and alveolar pressures, and therefore could decrease the risk of barotrauma and alveolar damage; b) high respiratory system resistances in ARDS have an increased smooth muscle tone component that can be reversible with salbutamol.

Successful diaphragmatic pacing for idiopathic alveolar hypoventilation.

We describe the case of a 17-year-old woman noted to have idiopathic alveolar hypoventilation, with multiple Intensive Care Unit (ICU) admissions because of acute respiratory failure (ARF) due to respiratory infections. After two years of diaphragmatic pacing arterial blood gases have substantially improved, without obstructive apnoea. Signs of right ventricular enlargement and pulmonary hypertension have decreased. Morning headache and diurnal somnolence have disappeared, and she is also able to perform more physical and mental activity, allowing her to enjoy a better quality of life.