Sequence analysis of coding DNA fragments of pfcrt and pfmdr-1 genes in Plasmodium falciparum isolates from Odisha, India

The global emergence and spread of malaria parasites resistant to antimalarial drugs is the major problem in malaria control. The genetic basis of the parasite's resistance to the antimalarial drug chloroquine (CQ) is well-documented, allowing for the analysis of field isolates of malaria parasites to address evolutionary questions concerning the origin and spread of CQ-resistance. Here, we present DNA sequence analyses of both the second exon of the Plasmodium falciparum CQ-resistance transporter (pfcrt) gene and the 5' end of the P. falciparum multidrug-resistance 1 (pfmdr-1) gene in 40 P. falciparum field isolates collected from eight different localities of Odisha, India. First, we genotyped the samples for the pfcrt K76T and pfmdr-1 N86Y mutations in these two genes, which are the mutations primarily implicated in CQ-resistance. We further analyzed amino acid changes in codons 72-76 of the pfcrt haplotypes. Interestingly, both the K76T and N86Y mutations were found to co-exist in 32 out of the total 40 isolates, which were of either the CVIET or SVMNT haplotype, while the remaining eight isolates were of the CVMNK haplotype. In total, eight nonsynonymous single nucleotide polymorphisms (SNPs) were observed, six in the pfcrt gene and two in the pfmdr-1 gene. One poorly studied SNP in the pfcrt gene (A97T) was found at a high frequency in many P. falciparum samples. Using population genetics to analyze these two gene fragments, we revealed comparatively higher nucleotide diversity in the pfcrt gene than in the pfmdr-1 gene. Furthermore, linkage disequilibrium was found to be tight between closely spaced SNPs of the pfcrt gene. Finally, both the pfcrt and the pfmdr-1 genes were found to evolve under the standard neutral model of molecular evolution.

Benznidazole levels in blood vary with age in rats

Benznidazole (Bz) exhibits toxic side effects in animal studies and clinical use. Reductive metabolism of Bz in liver microsomes modulates the duration of its chemotherapeutic effect and its toxicity. The rate of this metabolism depends on age and is less intense in newborns and youngsters than in adults. In the present study, we determined Bz blood levels in rats of different ages that received Bz intragastrically (100 mg/kg). We developed and validated a high-pressure liquid chromatography with UV detector method for determination of Bz levels in whole blood. Bz levels were significantly higher and persisted for longer periods of time in the blood of young rats when compared to that of adult animals.

Variation in haematological parameters in children less than five years of age with asymptomatic Plasmodium infection: implication for malaria field studies

During the season of high malaria transmission, most children are infected by Plasmodium, which targets red blood cells (RBCs), affecting haematological parameters. To describe these variations, we examined the haematological profiles of two groups of children living in a malaria-endemic area. A cross-sectional survey was conducted at the peak of the malaria transmission season in a rural area of Burkina Faso. After informed consent and clinical examination, blood samples were obtained from the participants for malaria diagnosis and a full blood count. Of the 414 children included in the analysis, 192 were not infected with Plasmodium, whereas 222 were asymptomatic carriers of Plasmodium infection. The mean age of the infected children was 41.8 months (range of 26.4-57.2) compared to 38.8 months (range of 22.4-55.2) for the control group (p = 0.06). The asymptomatic infected children tended to have a significantly lower mean haemoglobin level (10.8 g/dL vs. 10.4 g/dL; p < 0.001), mean lymphocyte count (4592/µL vs. 5141/µL; p = 0.004), mean platelet count (266 x 103/µL vs. 385 x 103/µL; p < 0.001) and mean RBC count (4.388 x 106/µL vs. 4.158 x 106/µL; p < 0.001) and a higher mean monocyte count (1403/µL vs. 1192/µL; p < 0.001) compared to the control group. Special attention should be applied when interpreting haematological parameters and evaluating immune responses in asymptomatic infected children living in malaria-endemic areas and enrolled in vaccine trials.

Slow clearance of Plasmodium vivax with chloroquine amongst children younger than six months of age in the Brazilian Amazon

Plasmodium vivax is the most widespread parasite causing malaria, being especially prevalent in the Americas and Southeast Asia. Children are one of the most affected populations, especially in highly endemic areas. However, there are few studies evaluating the therapeutic response of infants with vivax malaria. This study retrospectively evaluated the parasitaemia clearance in children diagnosed with vivax malaria during the first five days of exclusive treatment with chloroquine (CQ). Infants aged less than six months old had a significantly slower parasitaemia clearance time compared to the group of infants and children between six months and 12 years old (Kaplan-Meier survival analysis; Wilcoxon test; p = 0.004). The impaired clearance of parasitaemia in younger children with vivax malaria is shown for the first time in Latin America. It is speculated that CQ pharmacokinetics in young children with vivax malaria is distinct, but this specific population may also allow the detection of CQ-resistant parasites during follow-up, due to the lack of previous immunity.

Influence of age on the haemoglobin concentration of malaria-infected patients in a reference centre in the Brazilian Amazon

Anaemia is amongst the major complications of malaria, a major public health problem in the Amazon Region in Latin America. We examined the haemoglobin (Hb) concentrations of malaria-infected patients and compared it to that of malaria-negative febrile patients and afebrile controls. The haematological parameters of febrile patients who had a thick-blood-smear performed at an infectious diseases reference centre of the Brazilian Amazon between December 2009-January 2012 were retrieved together with clinical data. An afebrile community control group was composed from a survey performed in a malaria-endemic area. Hb concentrations and anaemia prevalence were analysed according to clinical-epidemiological status and demographic characteristics. In total, 7,831 observations were included. Patients with Plasmodium falciparum infection had lower mean Hb concentrations (10.5 g/dL) followed by P. vivax-infected individuals (12.4 g/dL), community controls (12.8 g/dL) and malaria-negative febrile patients (13.1 g/dL) (p < 0.001). Age, gender and clinical-epidemiological status were strong independent predictors for both outcomes. Amongst malaria-infected individuals, women in the reproductive age had considerably lower Hb concentrations. In this moderate transmission intensity setting, both vivax and falciparum malaria are associated with reduced Hb concentrations and risk of anaemia throughout a wide age range.

Prevention of congenital Chagas through treatment of girls and women of childbearing age

It is currently unknown whether treatment of Chagas disease decreases the risk of congenital transmission from previously treated mothers to their infants. In a cohort of women with Chagas disease previously treated with benznidazole, no congenital transmission of the disease was observed in their newborns. This finding provides support for the treatment of Chagas disease as early as possible.

School age children with HIV/AIDS: possible discrimination and attitudes against

Survey-based study what purpose was to analyse respondents’ opinions about contacts with HIV/AIDS-affected people. It was performed using a paper-pencil method during visits of respondents at primary care centres and on-line through a link to the questionnaire distributed among patients of primary care physicians. The study involved 302 respondents, 80% of whom were women; the average age was 34.48 years. The majority of respondents did not know anyone with HIV/AIDS (89.6%). About 83.3% claimed that they would not decrease contacts with HIV/AIDS-affected people. According to 64.1% of respondents, children with HIV/AIDS should go to kindergarten/public or non-public school. We selected a group of respondents, who previously were not but now are inclined to limit such contacts. These respondents can be a potential target group for HIV/AIDS educational programmes. Most respondents think that there is insufficient information about the HIV/AIDS in the mass media.

Hospital admissions due to ambulatory care sensitive conditions among children by age group and health region

OBJECTIVE to describe hospital admissions for ambulatory care sensitive conditions in children under five years of age in the State of Paraná, Brazil by condition type, age group and health region. METHOD a temporal ecological study was conducted using data from the Unified Health System Hospital Information System for the period 2000 to 2011. Conditions were grouped in accordance with the list of ambulatory care sensitive conditions in Brazil. RESULTS there was an increase in the rate of admissions for ambulatory care sensitive conditions in all age groups in 50% of the health regions, with a marked increase in children under the age of one. Pneumonia, gastroenteritis and asthma were the main causes of admissions. There was an increase in the proportion of overall admissions accounted for by pneumonia and gastroenteritis. CONCLUSION the increase in admissions reveals the need for actions to improve access to primary healthcare and provide effective treatment of the main ambulatory care sensitive conditions in order to prevent hospital admissions among children.

Functional response of Telenomus remus Nixon(Hymenoptera, Scelionidae) to Spodoptera frugiperda (J. E. Smith) (Lepidoptera, Noctuidae) eggs: effect of female age

Functional response of Telenomus remus Nixon (Hymenoptera, Scelionidae) to Spodoptera frugiperda (J. E. Smith) (Lepidoptera, Noctuidae) eggs: effect of female age. Functional response of 24-h and 48-h-old Telenomus remus adults was studied on Spodoptera frugiperda eggs. The study was carried out in climatic chamber regulated at 25 ± 1°C, 70 ± 10% RH and 12:12h (L: D). Females of T. remus were honey fed and individualized in glass vials along with 25, 50, 75, 100, 150, 200, 250 or 300 eggs of S. frugiperda for 24 h. Complete randomized design with ten replications was adopted. The parameters evaluated to construct the functional response curve were daily average parasitism, searching rate and oviposition time. It was observed that the higher the egg density, the higher the parasitism for 24-h and 48-h-old females although there was a tendency of parasitism stabilization at 150-egg density. The results showed a type II functional response curve for both 24-h and 48-h-old female.

Influence of age and diet on the performance of Cephalonomia stephanoderis (Hymenoptera, Bethylidae) a parasitoid of the coffee berry borer, Hypothenemus hampei (Coleoptera, Curculionidae)

The importance of age and feeding on the performance of Cephalonomia stephanoderis (Hymenoptera, Bethylidae), a parasitoid of the coffee berry borer, Hypothenemus hampei (Coleoptera, Curculionidae) was investigated in the laboratory. Groups of female parasitoids were subject to the following treatments: a group fed during one, five and ten days after emergence of adults with coffee borer larvae; another group fed only with honey solution during five days after emergence; and as a control, a third group was kept without food for five days. At the end of each treatment, survivorship, parasitoid activity (walking and flying capacity in an arena), search capacity for finding coffee borer-infested berries, host feeding and oviposition (on immature hosts), were assessed. Unfed females showed a significant decrease in survivorship compared to individuals that were fed. The type of meal (insects or honey) did not significantly influence parasitoid activity, search and oviposition capacities. Females fed with honey solution significantly consumed less immature coffee borers. Younger females (one day old) walked and flew out of the arena significantly faster than older ones (5 and 10 days old). Implications of these results are discussed on the performance of C. stephanoderis as a biological control agent of the coffee berry borer.

Effects of female diet and age on offspring sex ratio of the solitary parasitoid Pachycrepoideus vindemmiae (Rondani) (Hymenoptera, Pteromalidae)

Effects of female diet and age on offspring sex ratio of the solitary parasitoid Pachycrepoideus vindemmiae (Rondani) (Hymenoptera, Pteromalidae). Theories predict that females of parasitoid wasps would adjust the offspring sex ratio to environmental conditions in the oviposition patch, but the diet and age of females would also affect the sex ratio adjustment. Our focus was to test the effects of female diet and age on offspring sex ratio of the solitary parasitoid wasp, Pachycrepoideus vindemmiae (Rondani, 1875). Our results showed that females fed with honey had significantly less female biased offspring sex ratio than those fed only with water. Offspring sex ratio (male percentage) decreased with female age or female longevity at the beginning of oviposition but increased at the end. There should be a sperm limitation in P. vindemmiae females at the end of oviposition, and a higher frequency of unfertilized eggs were laid then. Females also laid more unfertilized eggs at the beginning of oviposition, which would be necessary to insure the mating among offspring. Male offspring developed faster and emerged earlier, which would also reduce the risk of virginity in offspring with female-biased sex ratio.

Age and multiple mating effects on reproductive success of Grapholita molesta (Busck) (Lepidoptera, Tortricidae)

The reproductive success of the oriental peach moth was evaluated in four experiments: 1) assessment of the mating duration, fecundity, fertility and longevity of females paired with virgin and immediately mated males; 2) mating duration, spermatophore size, fecundity, fertility and longevity in females paired with virgin and up to four times mated males; 3) receptivity of females to additional copulations after mating with virgin or mated males, and the effects of this behavior in female fecundity, fertility and longevity; 4) influence of insects age in the reproductive output. Males (33%) could copulate immediately after a previous copula. They were fertile until the fourth mating, but only in the first copula they transferred the longest (1.43 ± 0.10 mm) and widest (0.83 ± 0.11 mm) spermatophore, presenting the fastest mating duration (34.8 ± 2.62 min). A high proportion of females copulated by non-virgin males (84%) was receptive to other copulas, in comparison to those copulated by virgin males (32.4%). However, the fecundity, fertility, and longevity were similar among females that copulate once or more. The age was the most important factor affecting reproductive variables, where one and three day old insects had a significant higher fecundity, fertility and presented a shorter mating duration in comparison with older individuals. Results pointed out that the reproductive capacity of Grapholita molesta changes a little with respect to the analyzed factors, highlighting the elevated biotic potential of the species.

Influence of field slope and coffee plantation age on the physical properties of a red-yellow Latosol

In modern agriculture, several factors cause changes in the soil physical properties. The time of establishment of a crop (plantation age) and the slope are examples of factors that moderate the impact of mechanized operations on the soil structure. The objective of this study was to analyze the effect of machinery traffic on the physical properties of a Red-Yellow Latosol under coffee plantations with different ages (2, 7, 18, and 33 years) and slope positions (3, 9 and 15 %). Samples were collected from three positions between coffee rows (lower wheel track, inter-row and upper wheel track) and at two depths (surface layer and sub-surface). Changes in the total porosity, macroporosity, microporosity, organic matter, bulk density, and aggregate stability were investigated. Our results showed that the slope influenced the organic matter content, microporosity and aggregate stability. The soil samples under the inter-row were minimally damaged in their structure, compared to those from under the lower and upper wheel track, while the structure was better preserved under the lower than the upper track. The time since the establishment of the crop, i.e., the plantation age, was the main factor determining the extent of structural degradation in the coffee plantation.

Variations on the nutritional status of eucalypt as influenced by the genetic material and age of tree

The Diagnosis and Recommendation System (DRIS) was applied to eucalypt trees (hybrids of Eucalyptus grandis x E. urophylla) with different ages and growing under different environmental conditions for three different clones. The basic data were obtained from 1,986 trees of commercial stands cultivated in the states of Espírito Santo and south Bahia, Brazil. The DRIS indices were calculated using the Beaufils' Range formula and grouped according to the Nutrient Application Potential Response method. The objective of this paper was to evaluate the N, P and Ca status in eucalypt trees, regarding the tree ages and genetic materials. The DRIS indices discriminated differences in the nutritional status of the trees, both in relation to age and the genetic materials (clones). The results indicated that the deficiency of N and Ca tended to decrease with tree age, whereas the P deficiency tended to increase. Furthermore, of the three evaluated clones, those numbered 00014 and 00034 showed opposite trends regarding to N, P, and Ca nutrition, and the clone numbered 00021, in general, presented the highest degree of unbalanced nutrition of N, P and Ca.