Nanoparticulate carriers (NPC) for oral pharmaceutics and nutraceutics

The introduction of nanoparticulate carriers (NPC) in the pharmaceutic and nutraceutic fields has changed the definitions of disease management and treatment, diagnosis, as well as the supply food chain in the agri-food sector. NPC composed of synthetic polymers, proteins or polysaccharides gather interesting properties to be used for oral administration of pharmaceutics and nutraceutics. Oral administration remains the most convenient way of delivering drugs (e.g. peptides, proteins and nucleic acids) since these suffer similar metabolic pathways as food supply. Recent advances in biotechnology have produced highly potent new molecules however with low oral bioavailability. A suitable and promising approach to overcome their sensitivity to chemical and enzymatic hydrolysis as well as the poor cellular uptake, would be their entrapment within suitable gastrointestinal (GI) resistant NPC. Increasing attention has been paid to the potential use of NPC for peptides, proteins, antioxidants (carotenoids, omega fatty acids, coenzyme Q10), vitamins, probiotics, for oral administration. This review focuses on the most important materials to produce NPC for oral administration, and the most recent achievements in the production techniques and bioactives successfully delivered by these means.

Mutations in conserved amino acids in the KCNQ1 channel and risk of cardiac events in type-1 long-QT syndrome

BACKGROUND

Type-1 long-QT syndrome (LQT1) is caused by mutations in the KCNQ1 gene. The purpose of this study was to investigate whether KCNQ1 mutations in highly conserved amino acid residues within the voltage-gated potassium channel family are associated with an increased risk of cardiac events.

METHODS AND RESULTS

The study population involved 492 LQT1 patients with 54 missense mutations in the transmembrane region of the KCNQ1 channel. The amino acid sequences of the transmembrane region of 38 human voltage-gated potassium channels were aligned. An adjusted Shannon entropy score for each amino acid residue was calculated ranging from 0 (no conservation) to 1.0 (full conservation). Cox analysis was used to identify independent factors associated with the first cardiac event (syncope, aborted cardiac arrest, or death). Patients were subcategorized into tertiles by their adjusted Shannon entropy scores. The lowest tertile (score 0-0.469; n = 146) was used as a reference group; patients with intermediate tertile scores (0.470-0.665; n = 150) had no increased risk of cardiac events (HR = 1.19, P = 0.42) or aborted cardiac arrest/sudden cardiac death (HR = 1.58, P = 0.26), and those with the highest tertile scores (>0.665; n = 196) showed significantly increased risk of cardiac events (HR = 3.32, P <0.001) and aborted cardiac arrest/sudden cardiac death (HR = 2.62, P = 0.04). The increased risk in patients with the highest conservation scores was independent of QTc, gender, age, and beta-blocker therapy.

CONCLUSIONS

Mutations in highly conserved amino acid residues in the KCNQ1 gene are associated with a significant risk of cardiac events independent of QTc, gender, and beta-blocker therapy.

The conservation status of the tuco-tucos, genus Ctenomys (Rodentia: Ctenomyidae), in southern Brazil

The goal of conservation biology should be related to the preservation of species and also to the evolutionary and ecological processes that were responsible to form them and that are still acting. We review the conservation status of the species of tuco-tuco (Ctenomys torquatus, C. lami, C. minutus, and C. flamarioni) from southern Brazil, and relate these data to the geological history of a particular area in that region, the Coastal Plain of the States of Rio Grande do Sul and Santa Catarina. The implications of the data on these species from the Southeastern Brazil are also discussed in relation to the evolution and risk of extinction of these subterranean rodents.

Evolutionary relationships based on genetic and phenetic characters between Triatoma maculata, Triatoma pseudomaculata and morphologically related species (Reduviidae: Triatominae)

The maculata group currently comprises two species of Triatominae, Triatoma maculata and Triatoma pseudomaculata, which share morphologic and chromatic characteristics. In order to clarify the systematic status of these two vectors of Trypanosoma cruzi and to infer their evolutionary relationships, we performed an enzymatic, morphometric and cytogenetic comparison of them, also taking into account two sister species not included in the group (T. arthurneivai and T. wygodzinskyi). According to our results, T. maculata and T. pseudomaculata belong to distinct evolutionary lineages. Similarly, T. arthurneivai topotypes from Minas Gerais form an independent isolated group by morphometrics. Our results also support the specific status of the Triatoma population from São Paulo State (formerly referred to T. arthurneivai), and suggest the possibility that it is T. wygodzinskyi. Finally, we suggest that only the arboricolous T. pseudomaculata from northeast Brazil and the rupicolous sister species originated from São Paulo State should be classified together in the same group.

[Prevalence of oral changes in children attending public pediatric dental clinics in Ponta Grossa, PR, Brazil]

This investigation was carried out in order to determine the prevalence of oral alterations among 200 infants aged 0 to 24 months (108 males and 92 females), who were seen at public pediatric dental clinics from Ponta Grossa--PR, Brazil. The infants were examined during routine appointments. The data were analyzed and the results revealed that 21.00% of the children had oral conditions, which were more frequent among children aged 0 to 3 months (26.98%). The most prevalent condition was the inclusion cyst (35.71%), followed by benign migratory glossitis (23.81%) and candidiasis (11.90%). The prevalence of inclusion cysts was higher among females (10.87%), and the benign migratory glossitis was more frequently seen in males (6.48%). No tumors were found. With regard to the management of the conditions, it was noticed that no treatment was required in 76.19% of the cases. These findings are in agreement with those reported in the literature, and it was concluded that most of the oral conditions in infants are benign and do not require any treatment. In spite of that, health professionals (dentists and pediatricians) must be aware of those alterations in order to tranquilize the children's parents and to detect the need for any intervention.

[Ecology of mosquitoes in areas of the National Park of "Serra da Bocaina", Brazil: II - Monthly frequency and climatic factors]

OBJECTIVE

To establish the influence of climatic factors on the monthly frequency of mosquito fauna in areas of the National Park of Serra da Bocaina, Brazil.

METHODS

Human bait collections were conducted once a month, in diurnal and nocturnal hours, throughout 24 months, from January 1991 to December 1992.

RESULTS

A total of 11,808 adult mosquitoes belonging to 28 different species were collected. Anopheles cruzii, Runchomyia reversa, and Ru. frontosa were the most commonly found species each month. An. cruzii was found mostly from October to February; Ru. reversa and Ru. frontosa predominated in September. An. lutzi, Chagasia fajardoi, Coquillettidia chrysonotum, Aedes serratus, Trichoprosopon simile, Wyeomyia theobaldi, Ru. humboldti, and Ru. theobaldi are the second most prevalent species and they were found mostly throughout the hottest, rainiest and most humid months. Temperature and rainfall have positively influenced the incidence of the majority of the species.

CONCLUSIONS

The exuberant and well-preserved tropical forest of Mata Atlântica, rainfalls, and temperatures had a direct and significant contribution to the mosquito fauna in the park. In the months with greater rainfalls, temperatures and humidity, there was an increase in the density and diversity of mosquito species. The period from September to March was the most favorable for their proliferation. In the colder and drier period, from April to August, about 70% of the species showed a significant decline in number, and they were hardly found during these months.

[Newborn birth weight, maternal age group and delivery method]

This article has as its objective the study of the weight of the newly born, the age group of the mother and the kind of deliveries which took place in the maternity wards in Rio Branco--Acre Federal State--Brazil, in the period between 1994 and 1996. It was observed that 73.8% of the deliveries were regular and 25.5% were cesareans. Adolescents, between 10 to 14 years old represented 5.4% of the total of the deliveries. In relation to the weight of the newly born, 84.6% met the expectations, 7.4% were underweight and 6.6% were overweight. The present study also found that the data related to weight, age and gender was ignored in many cases, which shows flaws on the registration system of the institutions analyzed. As a conclusion, we would like to stress the importance of prenatal assistance both for the mother and the child, and also the effort on the part of the Maternity and Nursing management regarding the production and analysis of data.

Block of Kcnk3 by protons. Evidence that 2-P-domain potassium channel subunits function as homodimers

KCNK subunits have two pore-forming P domains and four predicted transmembrane segments. To assess the number of subunits in each pore, we studied external proton block of Kcnk3, a subunit prominent in rodent heart and brain. Consistent with a pore-blocking mechanism, inhibition was dependent on voltage, potassium concentration, and a histidine in the first P domain (P1H). Thus, at pH 6.8 with 20 mm potassium half the current passed by P1H channels was blocked (apparently via two sites approximately 10% into the electrical field) whereas channels with an asparagine substitution (P1N) were fully active. Furthermore, pore blockade by barium was sensitive to pH in P1H but not P1N channels. Although linking two Kcnk3 subunits in tandem to produce P1H-P1H and P1N-P1N channels bearing four P domains did not alter these attributes, the mixed tandems P1H-P1N and P1N-P1H were half-blocked at pH approximately 6.4, apparently via a single site. This implicates a dimeric structure for Kcnk3 channels with two (and only two) P1 domains in each pore and argues that P2 domains also contribute to pore formation.

The insulin-like growth factor-I system and hormone replacement therapy

OBJECTIVE

To determine the effects of hormone replacement therapy on plasma concentrations of free and total insulin-like growth factor (IGF)-I, IGF binding protein (BP)-1, and IGFBP-3.

DESIGN

Clinical study.

SETTING

Gynecologic clinic at a university hospital.

PATIENT(S)

Seventy-one postmenopausal women.

INTERVENTION(S)

Six cycles of four different hormonal replacement therapy regimens: oral conjugated estrogens, transdermal estradiol, oral conjugated estrogens and norethisterone, and transdermal estradiol and norethisterone acetate.

MAIN OUTCOME MEASURE(S)

Blood samples were collected before and after treatment for measurement of free and total IGF-I, IGFBP-1, and IGFBP-3.

RESULT(S)

Conjugated estrogen replacement therapy is associated with a decrease in plasma concentration of total IGF-I and increase in concentrations of free IGF-I and IGFBP-1. Transdermal estrogens have no effect on total and free IGF-I and IGFBP-1 concentrations. Oral norethisterone plus conjugated estrogens increased free IGF-I and IGFBP-1 concentrations but did not change IGF-I concentrations. Transdermal conjugated estrogens plus norethisterone acetate increased free IGF-I concentrations but not total IGF-I or IGFBP-1 concentrations. The plasma concentration of IGFBP-3 did not change in any group.

CONCLUSION(S)

Alterations in total IGF-I concentration can occur depending on the route of hormone replacement therapy administration. Free IGF-I concentrations were elevated in all study groups except that treated with transdermal estrogens.

Ecology of mosquitoes (Diptera: Culicidae) in areas of Serra do Mar State Park, State of São Paulo, Brazil. III. Daily biting rhythms and lunar cycle influence

The ecology of mosquito species (Diptera: Culicidae) was studied in areas of the Serra do Mar State Park, State of São Paulo, Brazil. The influence of the lunar cycle and the daily biting rhythms of mosquito populations were analyzed. Systematized biweekly human bait collections were made in a silvatic environment for 24 consecutive months (January 1991 to December 1992). A total of 20,591 specimens of adult mosquitoes belonging to 55 species were collected from 545 catches. Sabethini species were captured exclusively during daylight periods, with the exception of Trichoprosopon digitatum, while members of Anophelinae predominated during nocturnal hours. Members of the subfamily Culicinae that were collected primary during nocturnal periods included Culex nigripalpus, Coquillettidia chrysonotum and Cq. venezuelensis while daytime catches included Psorophora ferox and Ps. albipes. Others members of culicines mosquitoes that were collected during both day and night included: Aedes serratus, Ae. scapularis and Ae. fulvus. Lunar cycles did not appear to influence the daily biting rhythms of most mosquito species in the area, but larger numbers of mosquitoes were collected during the new moon. Ae. scapularis were captured mainly during the full moon.

Population dynamics of the free-living stages of Amblyomma cajennense (Fabricius, 1787) (Acari: ixodidae) on pastures of Pedro Leopoldo, Minas Gerais State, Brazil

A study on the population behavior of Amblyomma cajennense larvae, nymphs and adult free-living stages was carried out in Pedro Leopoldo County, Minas Gerais State, Brazil, from July 1995 to July 1997. Larvae were collected from pasture from April to October using the technique of drag sampling with flannelette. The maximal larval population was observed during autumn (May) representing, respectively, 48 and 82% of the total numbers recovered during the first and the second years of the experiment. Nymphs and adults were captured throughout the year by the use of traps with carbon dioxide as chemical attractant. The highest population of nymphs occurred during the winter (July), representing 39.5% of the total collected specimens. Adults had the highest population density on pasture during spring and summer, i.e., from August to May, with peaks in January and February, representing 46 and 38.3% of the total collected specimens during the first and the second year of study, respectively.

Proton block and voltage gating are potassium-dependent in the cardiac leak channel Kcnk3

Potassium leak conductances were recently revealed to exist as independent molecular entities. Here, the genomic structure, cardiac localization, and biophysical properties of a murine example are considered. Kcnk3 subunits have two pore-forming P domains and unique functional attributes. At steady state, Kcnk3 channels behave like open, potassium-selective, transmembrane holes that are inhibited by physiological levels of proton. With voltage steps, Kcnk3 channels open and close in two phases, one appears to be immediate and one is time-dependent (tau = approximately 5 ms). Both proton block and gating are potassium-sensitive; this produces an anomalous increase in outward flux as external potassium levels rise because of decreased proton block. Single Kcnk3 channels open across the physiological voltage range; hence they are "leak" conductances; however, they open only briefly and rarely even after exposure to agents that activate other potassium channels.

[Ecology of mosquitoes (Diptera: Culicidae) in areas of Serra da Bocaina National Park, Brazil. I. Habitat distribution]

OBJECTIVE

To assess the mosquito fauna in Serra da Bocaina National Park (PNSB), by collecting information through a general survey, and investigating the population behavior in habitats within the park with different vegetation.

METHODS

Human bait collections were conducted once a month for both the forest and households, in diurnal and nocturnal periods, three time a day, throughout 24 months, from January 1991 to December 1992.

RESULTS

A total of 11, 808 adult mosquitoes belonging to 28 species were collected. Runchomyia reversa and Anopheles cruzii were the most abundant, reaching 52.5% and 17.9% of the total collected specimens, respectively. In the dense forest, Ru. reversa comprised 59.4% of the total, followed by Ru. frontosa with 10.5%, and An. cruzii with 9.9%. In the high altitude fields and in gallery forest, An. cruzii was the most abundant (48.1%) followed by Ru. reversa (28.1%). Inside households An. cruzii was also the most prominent species, representing 73.7% of the total for that location. Coquillettidia chrysonotum was the only species mainly seen in the household surroundings, where its distribution was: 14.9% (indoors), 19.4% (close to the house), and 65.7% (outdoors). An. cruzii and Ru. reversa were found throughout the whole year and captured every month.

CONCLUSIONS

Mosquitoes in PNSB present an assynanthropic behavior, except for Cq. chrysonotum which lives preferentially in the household environment. Though An. cruzii is an assynantropic species it may approaches live near households and even invades and infest them for the blood meals. The occurrence of Aedes serratus in the household vicinity emphasizes its epidemiological importance as a potential vector of arboviruses. Sabethini are all exclusively sylvatic species.

[Sexual activity and sexually transmitted diseases in high school students in Rio Branco-Acre, Brazil]

This study was realized with 2.684 students of the high school in Rio Branco-Acre, Brazil, to verify aspects of the sexual activity and the occurrence of DST/AIDS. From the researched students, 48.9% had sexual intercourse, and the largest frequency was 34.3% for male sex, with the beginning at 13 years old, and for female sex 31.6%, with the beginning at 16 years old. The occurrence of mentioned DST/AIDS was: 58.4% for Hepatitis B, 39.4% for Monilíase and 2.2% for Gonorrhea. Among those ones who had their first sexual intercourse, 47.6% were with the boyfriend, 25.8% with the neighbor and 10.5% with the domestic maid. Concluding, the students who had sexual intercourse were 52.3% of private schools, 50.0% of federal ones, 45.7% of state ones and 41.8% of municipal ones.

Ecology of mosquitoes (Diptera: Culicidae) in areas of Serra do Mar State Park, State of São Paulo, Brazil. II - habitat distribution

The mosquito (Diptera: Culicidae) ecology was studied in areas of Serra do Mar State Park, State of São Paulo, Brazil. Systematized biweekly human bait collections were made three times a day, for periods of 2 or 3 h each, in sylvatic and rural areas for 24 consecutive months (January 1991 to December 1992). A total of 24, 943 adult mosquitoes belonging to 57 species were collected during 622 collective periods. Aedes scapularis, Coquillettidia chrysonotum, Cq. venezuelensis, Wyeomyia dyari, Wy. longirostris, Wy. theobaldi and Wy. palmata were more frequently collected at swampy and at flooded areas. Anopheles mediopunctatus, Culex nigripalpus, Ae. serratus, Ae. fulvus, Psorophora ferox, Ps. albipes and the Sabethini in general, were captured almost exclusively in forested areas. An. cruzii, An. oswaldoi and An. fluminensis were captured more frequently in a residence area. However, Cx. quinquefasciatus was the only one truly eusynanthropic. An. cruzii and Ae. scapularis were captured feeding on blood inside and around the residence, indicating that both species, malaria and arbovirus vectors respectively, may be involved in the transmission of these such diseases in rural areas.

Ecology of mosquitoes (Diptera: culicidae) in areas of Serra do Mar State Park, State of São Paulo, Brazil. I - monthly frequency and climatic factors

The ecology of mosquitoes were studied (Diptera: Culicidae) in areas of Serra do Mar State Park, State of São Paulo, Brazil. Systematized monthly human bait collections were made three times a day, for periods of 2 or 3 h each, in sylvatic and rural areas for 24 consecutive months (January 1991 to December 1992). A total of 24, 943 specimens of adult mosquitoes belonging to 57 species were collected during 622 collective periods. Coquillettidia chrysonotum was the most frequent collected mosquito (45.8%) followed by Aedes serratus (6.8%), Cq. venezuelensis (6.5%), Psorophora ferox (5.2) and Ps. albipes (3.1%). The monthly averages of temperature and relative humidity were inserted in the ten-year average limits of maximum and minimum of the previous ten-years. Rainfall accompanied the curve of the ten-year averages. Those climatic factors were influential in the incidence of some species; temperature: Anopheles cruzii, An. mediopunctatus, Ae. scapularis, Ae. fulvus, Cq. chrysonotum, Cq. venezuelensis, Runchomyia reversa, Wyeomyia dyari, Wy. confusa, Wy. shannoni, Wy. theobaldi and Limatus flavisetosus; relative humidity: Ae. serratus, Ae. scapularis, Cq. venezuelensis and Ru. reversa; rainfall: An. cruzii, Ae. scapularis, Ae. fulvus, Cq. venezuelensis Ru. reversa, Wy. theobaldi and Li. flavisetosus.

Actions of general anaesthetics and arachidonic pathway inhibitors on K+ currents activated by volatile anaesthetics and FMRFamide in molluscan neurones

1. K+ currents activated by volatile general anaesthetics (IK(An)) and by the neuropeptide FMRFamide (IK(FMRFa)) were studied under voltage clamp in isolated identified neurones from the pond snail Lymnaea stagnalis. 2. IK(An) was activated by all the volatile anaesthetics studied. The maximal responses varied from agent to agent, with halothane sevoflurane > isoflurane > enflurane approximately chloroform. 3. IK(An) was inhibited rather than activated by the n-alcohols from hexanol to dodecanol and by the 6- and 8-carbon cycloalcohols. The n-alcohols exhibited a cutoff effect, with dodecanol being unable to half-inhibit IK(An). 4. Unlike IK(An) which did not desensitize at reasonable halothane concentrations, IK(FMRFa) desensitized at most FMRFamide concentrations studied. This desensitization could be substantially removed by halothane. Nonetheless, both IK(An) and IK(FMRFa) had similar sensitivities to the potassium channel blockers tetraethylammonium and 4-aminopyridine, consistent with both currents flowing through the same channels. Responses to low concentrations of halothane and FMRFamide showed synergy. 5. The phospholipase A2 inhibitor aristolochic acid inhibited IK(An), consistent with a role for arachidonic acid (AA). The lipoxygenase and cyclooxygenase inhibitor nordihydroguaiaretic acid blocked IK(FMRFa) but did not affect IK(An). IK(An) and IK(FMRFa) were little affected by the cyclooxygenase inhibitor indomethacin. These findings suggest that neither lipoxygenase nor cyclooxygenase pathways of AA metabolism are involved in the anaesthetic activation of IK(An. 6. Inhibitors of a third, cytochrome P450-mediated, pathway of AA metabolism (clotrimazole and econazole) potently blocked IK(An), suggesting possible roles for certain cytochrome P450 isoforms in the activation of IK(An).

Host specificity of Amblyomma cajennense (Fabricius, 1787) (Acari: Ixodidae) with comments on the drop-off rhythm

The parasitic specificity of larval, nymph and adult Amblyomma cajennense on six different host species: Oryctolagus cuniculus, Rattus norvegicus, Gallus gallus domesticus, Anas platyrhynchus, Coturnix coturnix and Streptopelia decorata is described. In terms of the numbers of larvae and nymphs recovered, O. cuniculus was the best host species. The modal day for drop-off of larvae and nymphs was day three for the mammal hosts, but variable in the birds. We conclude that adult A. cajennense have a strong degree of specificity due to the fact that the tick failed to complete its life cycle on any of the evaluated hosts. The immature stages, on the other hand, showed a low level of specificity, most especially in the larval stage, indicating the existence of secondary hosts which probably serve as dispersers in the wild. The results also indicated a variable drop-off rhythm for larvae and nymphs in two periods, diurnal (6-18 hr) and nocturnal (18-6 hr), which differed depending upon the host.

[Auditorship and errors: emphasis on nursing records]

This study examines 34 procedure billing reports collected at health care facilities that participated in SIA-SIH/SUS activities in Rio Branco--Acre in 1994/1995. It aims at identifying and analyzing any errors found in the procedure notes. This study also used sub-categories which were defined through content similarity. A total of 491 errors were found in the procedure billing reports. This represents an average of 14.4% of errors per procedure billing report. When the procedure billing reports were analyzed using 8 criteria, 198 (40.6%) administrative errors, 121 (24.6%) doctors errors, 99 (20.2%) nurses errors, and 51 (10.2%) accounting errors were detected. When the nurses' errors were further examined, it was detected that 34 (34.3%) were due to nurses notes and 15 (15.1%) as a result of erroneous medication administration. It was concluded that nursing staff is not following the standard note taking procedures. This places not only the patients at risk but also health care professionals and health care facilities which are responsible for patient care.

[Prevalence of Anophelines (Diptera: Culicidae) during sunset in areas of the Itaipu Hydroelectric plant in Guaíra county, state of Paraná, Brazil]

Systematic collections of anophelines were conducted from November 1994 to August 1995 from 18:00 to 20:00 hr using Shannon traps and human-bait along the lake margin which forms the Itaipu Hydroelectric reservoir, State of Paraná, Brazil. Species prevalence was studied at 15 min intervals. Anopheles albitarsis sensu latu and An. galvaoi, were the most frequently collected mosquitoes. All Anopheles species populations peaked between 18:45 and 19:30 hr. The observations illustrate the existence of a haematophagic activity cycle during the early evening hours: exogenous stimulus (the beginning of sunset)-->Shannon trap (light attraction)-->human bait (haematophagy)-->rest and digestion-->exogenous stimulus-->Shannon trap or surrounding vegetation. The greater abundance of An. albitarsis collected in human-bait and Shannon trap suggests it may be a potential malaria vector in the region.

Some ectoparasites of commensal rodents from Huambo, Angola

Eight species of ectoparasites were collected from 166 commensal rodents, including Rattus rattus (L.), Rattus norvegicus (Berkenhout), and Mus musculus (L.), from January to December 1986, in Huambo, Angola. The oriental rat flea, Xenopsylla cheopis (Rothschild), was the predominant species with respect to mean intensity and prevalence. Other fleas collected were Ctenophthalmus (Ethioctenophthalmus) machadoi Ribeiro, Dinopsyllus (Dinopsyllus) smiti Ribeiro, and Echidnophaga gallinacea (Westwood). The mite Laelaps (Echinolaelaps) muricola Trägärdh, the louse Polyplax spinulosa (Burmeister), one species of Ixodes Latreille, and one species of Ornithonyssus Sambon were also recorded. The following represent new host records: C. machadoi from R. rattus and R. norvegicus, D. smiti from M. musculus, and L. muricola from R. rattus and M. musculus. For the first time, the monthly flea indices throughout the year are presented for Angola.