22 research outputs found
Aegla platensis Schmitt, 1942 (Decapoda: Anomura) um predador de imaturos de Simuliidae (Diptera: Culicomorpha)
A Randomised Controlled Trial to Assess the Efficacy of Dihydroartemisinin-Piperaquine for the Treatment of Uncomplicated Falciparum Malaria in Peru
Background. Multi-drug resistant falciparum malaria is an important health problem in the Peruvian Amazon region. We carried out a randomised open label clinical trial comparing mefloquine-artesunate, the current first line treatment in this region, with dihydroartemisinin-piperaquine. Methods and Findings. Between July 2003 and July 2005, 522 patients with P. falciparum uncomplicated malaria were recruited, randomized (260 with mefloquine-artesunate and 262 with dihydroartemisinin-piperaquine), treated and followed up for 63 days. PCR-adjusted adequate clinical and parasitological response, estimated by Kaplan Meier survival and Per Protocol analysis, was extremely high for both drugs (99.6% for mefloquine-artesunate and 98.4% and for dihydroartemisinin-piperaquine) (RR: 0.99, 95%CI [0.97-1.01], Fisher Exact p=0.21). All recrudescences were late parasitological failures. Overall, gametocytes were cleared faster in the mefloquine-artesunate group (28 vs 35 days) and new gametocytes tended to appear more frequently in patients treated with dihydroartemisinin-piperaquine (day 7: 8 ( 3.6%) vs 2 (0.9%), RR: 3.84, 95%CI [0.82-17.87]). Adverse events such as anxiety and insomnia were significantly more frequent in the mefloquine-artesunate group, both in adults and children. Conclusion. Dihydroartemisinin-piperaquine is as effective as mefloquine-artesunate in treating uncomplicated P. falciparum malaria but it is better tolerated and more affordable than mefloquine-artesunate (US18.65 on the local market). Therefore, it should be considered as a potential candidate for the first line treatment of P. falciparum malaria in Peru. Trial Registration. ClinicalTrials.gov NCT00373607 [http://www.clinicaltrials.gov/ct/show/NCT00373607]
First record of Craspedacusta sowerbii Lankester, 1880 (Hydrozoa, Limnomedusae) in a natural freshwater lagoon of Uruguay, with notes on polyp stage in captivity
Abstract The freshwater cnidarian Craspedacusta sowerbii Lankester 1880, has invaded lakes and ponds as well as artificial water bodies throughout the world. The first record in Uruguay corresponding to the jellyfish was made in 1961 in two artificial fountains, with no mention of the polyp form. Although local reports of other related polyp species have been made, information on the benthic form of C. sowerbii is lacking. Here we report the finding of live frustules, solitary individuals, medusae and colonies from a natural lagoon in August 2010, allowing us to observe the morphology and behavior of the polyp stage in captivity. In addition, molecular identification and remarks on the potencial path of introduction are presented. This is the first record in Uruguay of both polyp and medusa stages of C. sowerbii in a natural water body, Del Medio Lagoon (Dpto. de Florida), Uruguay
New species of Temnocephala (Platyhelminthes, Temnocephalida) ectosymbiont on vulnerable species of aeglids (Crustacea, Anomura) from the Neotropical Region
Telomere length shortening and gastric cancer risk in a high risk Polish population
Abnormally short telomeres have been associated with chronic inflammation and chromosomal instability. Increased rates of telomere shortening are present in gastric tumor tissue and in gastric epithelium tissue infected with Helicobacter pylori (H. pylori), a known risk factor for gastric cancer. However, no study has examined the role of telomere length in peripheral blood genomic DNA in relation to H. pylori infection and gastric cancer risk.
In a population-based study of 300 cases and 416 controls conducted in Warsaw, Poland, between 1994 and 1996, we examined: i) the association between telomere length in peripheral blood genomic DNA and potential gastric cancer risk factors, including H. pylori infection among healthy controls; ii) the risk of gastric cancer associated with shortened telomeres. Telomere length (TL) was measured in duplicate using real-time quantitative PCR. The mean of the two measurements was used to calculate the relative ratio of telomere repeat to single-copy gene number (T/S ratio). We used regression models to obtain age-adjusted p-values for the correlations of telomere length with H. pylori infection and other exposures. Age-adjusted logistic regression models were used to estimate gastric cancer risk associated with telomere length. Among controls, telomere length was significantly shorter in H. pylori-infected individuals (TL=1.32, SD=0.34) than in uninfected subjects (TL=1.44, SD=0.35; p =0.03). We also observed significant inverse correlations of telomere length with age (p<0.001), pack years of cigarette smoking (p=0.003), total years of alcohol consumption (p=0.007), and low weekly fruit intake (p=0.02). When cases and controls were compared, telomere length was significantly shorter in cases (TL=1.25; SD=0.34) than in controls (TL=1.34; SD=0.35) [p=0.0008]. Furthermore, gastric cancer risk was significantly increased with decreasing telomere length (OR=2.00, 95% CI=1.32-3.02 for subjects in the lowest quartile (shortest) of telomere length compared to those in the highest quartile of telomere length; P trend<0.001).
Our results suggest that H. pylori infection and other potential gastric cancer risk factors are associated with shorter telomeres. Shortened telomere length was associated with an increased risk of gastric cancer in this high-risk Polish population
Limnological investigation of the rivers Uracoa, Yabo, Morichal Largo and Claro in the Eastern Plains of Venezuela
Telomere length in peripheral leukocyte DNA and gastric cancer risk
Telomere length reflects lifetime cumulative oxidative stress from environmental exposures, such as cigarette smoking and chronic inflammation. Shortened telomere length is thought to cause genomic instability and has been associated with several cancers. We examined the association of telomere length in peripheral leukocyte DNA with gastric cancer risk as well as potential confounding factors and risk modifiers for telomere length-related risk. In a population-based study of gastric cancer conducted in a high-risk population in Warsaw, Poland, between 1994 and 1996, we measured relative telomere length in 300 cases and 416 age- and gender-matched controls using quantitative real-time PCR. Among controls, telomeres were significantly shorter in association with aging (P < 0.001), increasing pack-years of cigarette smoking (P = 0.02), decreasing fruit intake (P = 0.04), and Helicobacter pylori positivity (P = 0.03). Gastric cancer cases had significantly shorter telomere length (mean +/- SD relative telomere length, 1.25 +/- 0.34) than controls (1.34 +/- 0.35; P = 0.0008). Gastric cancer risk doubled [odds ratio (OR), 2.04; 95% confidence interval (95% CI), 1.33-3.13] among subjects in the shortest compared with the highest quartile of telomere length (P(trend) < 0.001). Telomere length-associated risks were higher among individuals with the lowest risk profile, those H. pylori-negative (OR, 5.45; 95% CI, 2.10-14.1), nonsmokers (OR, 3.07; 95% CI, 1.71-5.51), and individuals with high intake of fruits (OR, 2.43; 95% CI, 1.46-4.05) or vegetables (OR, 2.39; 95% CI, 1.51-3.81). Our results suggest that telomere length in peripheral leukocyte DNA was associated with H. pylori positivity, cigarette smoking, and dietary fruit intake. Shortened telomeres increased gastric cancer risk in this high-risk Polish population
Mitochondrial DNA copy number and risk of gastric cancer : a report from the Shanghai Women's Health Study
BACKGROUND:
Mitochondrial DNA (mtDNA) is an approximately 16,000-bp circular double-stranded DNA molecule that is a prime target of oxidative damage. Several somatic mutations in mtDNA have been observed in gastric tumors, suggesting an involvement in gastric cancer risk and progression. mtDNA copy number in leukocyte DNA has also been linked to several other cancers, although the temporal relationship between mtDNA and cancer has not been adequately explored.
METHODS:
Using a nested case-control study design, we examined the association between mtDNA copy number in 162 gastric cancer cases and 299 matched controls within the Shanghai Women's Health Study, a large population-based prospective cohort. Relative mtDNA copy number was measured in triplicate by a quantitative real-time PCR assay in peripheral leukocytes.
RESULTS:
mtDNA copy number levels were comparable among cases and controls, with a median of 1.04 [interquartile range (IQR), 0.87-1.25] and 1.06 (IQR, 0.88-1.29), respectively. Overall, mtDNA was not associated with gastric cancer risk. However, the association differed when stratified by the time between sample collection and cancer diagnosis. An association between low levels of mtDNA copy number (<median) and gastric cancer risk was apparent among earlier diagnosed cases, in particular, those diagnosed within 2 years of sample collection (OR = 5.32; 95% CI = 1.03-27.60). This association was not present as the time between sample collection and cancer diagnosis increased. CONCLUSIONS AND IMPACT: Our findings suggest that there is no association between leukocyte mtDNA copy number and risk of developing gastric cancer; however, we observed a possible early disease effect on mtDNA copy number levels
Preliminary comparative data on the fauna of the pleuston in the southern Pantanal, Brazil, with emphasis on the microcrustaceans
A new species of Stratiodrilus (Polychaeta, Histriobdellidae) from freshwater crayfishes of southern Brazil
A new species of polychaete, Stratiodrilus vilae, epizoic on Parastacus brasiliensis (von Martens, 1869) and P. defossus Faxon, 1898, is described from the State of Rio Grande do Sul, southern Brazil. The new species has one pair of long, anal, conical ventral lobes, one on each side of the anus, claspers in the males, and one pair of tubercles in each of the posterior locomotor appendages; and the jaw apparatus not reaching the limit between the head and the first segment