Ketalization of 2-heptanone to prolong its activity as mite repellant for the protection of honey bees.

BACKGROUND: 2-Heptanone is a volatile liquid known to be effective in protecting honey bees from parasitic mite infestations in hives. The present study aimed to show that chemical derivatives of 2-heptanone would release the ketone for a significantly longer time than it takes for the pure ketone to evaporate and preferably for as long as two brood cycles of a honey bee (42 days). RESULTS: A liquid ketal of 2-heptanone with glycerol (Glyc-Ket) and solid ketals of the ketone with polyvinyl alcohol (PVAl-Ket), containing different amounts of the ketone, were synthesized. The fully resolved 1 H and 13 C nuclear magenetic resonance (NMR) spectra of the ketals are discussed. In the case of the polymer, differential scanning calorimetry (DSC) of a ketal was also compared with the unketalized polyvinyl alcohol. The length of time for which 2-heptanone was released by the ketals was determined by gas chromatography-mass spectrometry of the headspace. In the case of Glyc-Ket, the concentration of the 2-heptanone in the liquid phase was also monitored by 1 H NMR spectroscopy. The deketalization was pH dependent, ranging between 2.0 and 2.5 for Glyc-Ket and between 2.0 and 3.5 for PVAl-Ket. CONCLUSION: Under bee hive conditions, the release of 55 mmol 2-heptanone from Glyc-Ket lasted for 42 days, whereas the release of the ketone from the PVAl-Ket with a similar amount of the ketone lasted for 23 days, versus a maximum of 17 days for an equivalent amount of the pure ketone. These ketals therefore have the potential to be effective mite repellants for the protection of honey bees. © 2019 Society of Chemical Industry.

Phenotypic analysis of adults of Fasciola hepatica, Fasciola gigantica and intermediate forms from the endemic region of Gilan, Iran.

Fascioliasis is an important human and animal disease caused by Fasciola hepatica and Fasciola gigantica. In Iran, the distribution of these two species overlaps in most areas, including the northern human endemic province of Gilan where both fasciolids are simultaneously found in individual cattle and buffaloes. A phenotypic study of fasciolid adult flukes from naturally infected bovines from Gilan was carried out by means of an exhaustive morphometric analysis using traditional microscopic measurements and an allometric model. The Iranian fasciolids were compared to F. hepatica and F. gigantica standard populations, i.e. from geographical areas where both species do not co-exist (Bolivia and Burkina Faso, respectively). Although morphometric values somewhat overlapped, there were clear differences in allometric growth. The allometric function was adjusted to 25 pairs of variables. Results obtained revealed that Iranian F. hepatica-like specimens are larger than the F. hepatica standard and Iranian F. gigantica-like specimens are longer and narrower than the F. gigantica standard, but with smaller body area. Measurements which permit a specific differentiation in allopatric populations (distance between ventral sucker and posterior end of the body; ratio between body length and body width) overlap in the specimens from Gilan, thus proving the presence of intermediate forms. When compared to the standard populations, the different Iranian fasciolid morphs show greater differences in F. gigantica-like specimens than in F. hepatica-like specimens. This study shows that simple, traditional microscopic measurements may be sufficient for the morphometric characterisation of fasciolids, even in areas where intermediate forms are present.

Tetrameres (Tetrameres) grusi (Shumakovich, 1946) (Nematoda: Tetrameridae) in Eurasian cranes (Grus grus) in central Iran.

The proventriculi of 11 Eurasian cranes (Grus grus) from central Iran were examined for the existence of parasitic helminths. Preliminary reports suggested that the death of these birds was related to untimely cold weather. Nine proventriculi (82%) were heavily infected by the nematode Tetrameres grusi. Glandular structure of the infected proventriculi was replaced by epithelial atrophy but significant inflammatory reactions were not observed in any of the infected organs. In serious infections, the nematode produced vast structural and functional changes, causing organ dysfunction and glandular necrosis. The coincidence of heavy helminth infection at times of environmental stress may lead to debilitation, wasting, and perhaps mortality in migratory cranes.

Prevalence of intestinal helminths in Khuzestan, Southwest Iran, 1977.

Large scale studies were performed to determine the prevalence of various intestinal helminth infections in urban and rural areas of Khuzestan Province, southwest Iran. A total of 16,361 stool samples from people in 105 villages and 14 small towns were examined by the formalin-ether concentration method. Ascaris, hookworms, Trichostrongylus, Trichuris, and Hymenolepis nana showed the highest prevalence. Hookworms and Trichostrongylus were twice as prevalent in rural than in urban areas; in contrast, H. nana was more prevalent in urban areas while the level of Ascaris infections was not significantly different. The intensity of Ascaris and hookworm infections, as estimated by the number of eggs/g of feces, was higher in rural than in urban areas.

Comparison of adult somatic and cysteine proteinase antigens of Fasciola gigantica in enzyme linked immunosorbent assay for serodiagnosis of human fasciolosis.

Fasciolosis caused by Fasciola hepatica and Fasciola gigantica is one of the major public health problems in the world and in Iran. Considering that stool examination for Fasciola eggs is not a sensitive method and immunodiagnosis methods are more applicable for this purpose, so the present study was conducted to compare the somatic (S) and cysteine proteinase (CP) antigens of F. gigantica in IgG-ELISA to diagnose human fasciolosis. Serum samples obtained from 100 individuals collected during the fasciolosis outbreak in 1999 in the Gilan province of Northern Iran that were coprologically positive for fasciolosis were analyzed by IgG-ELISA. Sera from healthy control individuals, not infected with any parasitic diseases (n=50) and from others with different parasitic infections including hydatidosis (n=40), toxocariosis (n=20), amoebiosis (n=10), and malaria (n=5) were examined as well. The cut-off point for (S) and CP was 0.40 and 0.35, respectively. All 100 individuals that showed clinical manifestations of fasciolosis, were also seropositive using both antigens, whereas all 50 non-infected controls were seronegative, therefore the sensitivity of the test was 100% for both antigens. The specificity of (S) and CP antigens were calculated as 96.9 and 98.4%, respectively. The positive and negative predictive values of the test regarding (S) antigen were 96 and 100%, whereas these values as for CP antigen were 98 and 100% correspondingly. Two individuals with hydatidosis and two with toxocariasis had antibodies that were reactive against (S) antigen, whereas concerning CP antigen, one individual with hydatidosis and another with toxocariasis showed cross-reactivity against it. We have demonstrated that altogether CP antigen provides a more conclusive diagnosis as possessing lower cut-off and enabling better to discriminate between seronegative and seropositive subpopulations.

Toxocara cati: hatching of second stage larvae.

A method for hatching second-stage larvae of Toxocara cati is described. Whole adult worms are processed by centrifugation in the presence of hypochlorite which allows the grinding step to be eliminated. The technique is more rapid and a high yield is obtained.

A versatile approach for modeling and simulating the tacticity of polymers.

We are introducing a versatile computerized approach to model and simulate polymer tacticities using seven single-stage statistical models. The theory behind the models, e.g., Bovey's versus Price's, Bernoullian, 1st or 2nd order Markovian, enantiomeric types, and combinations thereof is explained. One of the models, "E-B gen", which can be used to produce four types of enantiomorphically controlled tacticities, and the pentad distribution for the model "E-M1" are reported here for the first time. The relations of chain-end controlled models to binary copolymerizations are discussed in detail, and equations for the conversion of tacticity based probabilities to reactivity ratios to obtain related n-ad distributions are presented. The models were applied to 20 polymers with exemplary tacticities found in the literature. A related software program ("Polytact") based on Microsoft's Excel has been designed to calculate all relevant characteristics of the polymer tacticity and to present them in graphical form in a user-friendly manner. The program can be used to produce graphs of the triad, pentad and sequence length distributions and a simulation of 50 monomer repeat units in the polymer for each of the seven models. One of the main intended uses of the program is to compare the computed n-ad distributions to those of experimental polymers obtained from NMR spectroscopy and to gain insight into the polymerization mechanisms.

Human Gongylonema infection in Iran.

The first human infection with Gongylonema in Iran is reported in a 35-year-old Iranian woman with complaints of one year duration and treated as a psychotic patient. Two worms, a male, and a female, were retrieved, described, and identified as G. pulchrum based on their morphological characteristics.

Studies on trematodes of the family Heterophyidae (Odhner, 1914) in Iran: 1. Preliminary epidemiological surveys in man and carnivores in Khuzestan.

Trematodes of the family Heterophyidae in man and carnivores were studied in Khuzestan, south-west Iran. Eight hundred and eleven stool samples from a population of 3400 in 13 villages in a swampy area located in central Khuzestan were examined by the formalin-ether concentration technique. The following helminths were found: Ascaris lumbricoides 7%, Trichostrongylus spp. 53%, hookworms 4+, Trichuris trichiura 5%, Hymenolepis nana 12% and heterophyid spp. 8%. Post-mortem examination of carnivores revealed that 14.2% of jackals, 33.3% of foxes and 2.5% of dogs were infected with heterophyids, namely Metagonimus yokogawai, Heterophyes heterophyes and H. katsuradai. The freshwater snails Melanoides and Melanopsis spp. and brackish water fishes Barbus spp. and Mugil spp. were thought to be the intermediate hosts of these flukes in this area. This is the first report of heterophyid infection in man and carnivores in Iran.

Hookworm infection and blood changes in the rural population of Dezful area in Khuzestan, South-West of Iran.

Hookworm infection and blood changes relationship in the 937 infected persons in 6 villages of Dezful area in Khuzestan, South West of Iran, were studied. The most prevalent intestinal helminths in the area were Ascaris lumbricoides 21%, Ancylostoma duodenale 35%, Trichostrongylus spp. 17% and Hymenolepis nana 17%. Only 2% of the hookworm infected persons showed high intensity of infection which accompanied with rather low haemoglobin level of 9.4 g/100. The eosinophil level was 12-d16.5%. The results of this study indicates that the anaemia produced by hookworm infection in Khuzestan is not significant.

Distribution and ecology of Bulinus truncatus in Khuzestan, Iran.

The results of a 5-year study on the distribution and ecology of Bulinus truncatus in Khuzestan, south-western Iran, are described. Live snails were found in 4 foci, namely, the main focus, the upper Karun River, the lower Karkheh River, and the Bala Rud watershed; in addition, dead snails were found in 3 other foci. The patchy distribution of snails was related to the presence of surface waters and to their chemical composition.Monthly observations on the population dynamics of the snails and on the role of the snails in the transmission of Schistosoma haematobium and S. bovis were carried out in 14 ponds, 9 canals, 5 swamps, 2 field drains, 1 spring and 1 stream-pool. In standing waters, the peak of snail population could potentially occur in 2 seasons-May-July and November-January-but the main seasons for the transmission of mammalian schistosome cercariae were April-May and October-November. In flowing waters, a higher number of snails might be found in summer in some canals and in winter in another group of canals. Canals were found to be more important sites of transmission of human schistosomes than were village ponds. Transmission took place mainly in hot months when man-water contacts were greatest. Village ponds accessible to livestock were found to be important in the transmission of bovine schistosomiasis. As new irrigation systems have been expanding in this area of Khuzestan, more attention should be paid to flowing waters than to standing waters in future schistosomiasis control programmes.

Host-parasite relationship of Bulinus truncatus and Schistosoma haematobium in Iran. 1. Effect of the age of B. truncatus on the development of S. haematobium.

This paper is the first of a series of four on various aspects of the interaction between Bulinus truncatus and the bilharziasis parasite Schistosoma haematobium. It describes laboratory studies conducted to determine the effect of the age of B. truncatus on the development of S. haematobium. The results indicated (1) that the young snails could be infected even if they were one day old; (2) that the infection rates were higher in the snails of two to five weeks of age than in those of one week; (3) that the cercarial-incubation period was shorter in the young snails than in the older ones; (4) that the survival rate of the snails in the cercarial-incubation period was lower in the young snails than in the older ones; (5) that the survival rate of the cercaria-shedding snails was also apparently lower in the young ones than in the older ones; (6) that the maximum life-span for a cercaria-positive snail extended to 329 days after the date of exposure to infection.

Host-parasite relationship of Bulinus truncatus and Schistosoma haematobium in Iran. 2. Effect of exposure dosage of miracidia on the biology of the snail host and the development of the parasites.

Laboratory experiments were carried out to study the development of Bulinus truncatus and the larval stages of Schistosoma haematobium after the snails had been exposed to various numbers of miracidia. The results showed: (1) that in the cercarial-incubation period the growth and survival rate of snails was not influenced by the development of the larval stages of S. haematobium, but that in the cercaria-shedding period the life-span of the infected snails was shorter than that of the non-infected controls; (2) that reduction of oviposition was proportional to the exposure of miracidia; (3) that the length of the cercarial-incubation period in snails was inversely proportional to the exposure number of miracidia; (4) that all the snails exposed to 20 miracidia (the maximum exposure number used) shed cercariae; (5) that snails exposed to one miracidium each shed fewer cercariae than those exposed to two or more miracidia each; and (6) that the peak of cercaria-shedding occurred 40 to 90 days after the shedding had started, varying in different groups.

Host-parasite relationship of Bulinus truncatus and Schistosoma haematobium in Iran. 3. Effect of water temperature on the ability of miracidia to infect snails.

Laboratory studies were made in Iran to test the effect of water temperature on the ability of the miracidia of S. haematobium to penetrate B. truncatus. Snails three to four weeks old were exposed to two miracidia each for two hours at nine water temperatures ranging from 10 degrees C to 38 degrees C. After exposure, all the snails were kept in aquaria at room temperature. The cercaria-positive rates of these nine groups of snails showed that the optimum exposure temperature was in the range 20 degrees C-30 degrees C. The infection rate was low at temperatures outside this range. It is concluded that the optimum transmission seasons in bilharziasis-endemic areas in Iran are spring and autumn but that transmission still occurs in hot summer and cold winter months although to a much smaller extent.

Host-parasite relationship of Bulinus truncatus and Schistosoma haematobium in Iran. 4. Effect of month of infection on cercarial-incubation periods of S. haematobium and S. bovis.

Studies were conducted each month for one year to determine the cercarial-incubation periods of Schistosoma haematobium and Schistosoma bovis in Bulinus truncatus for different months of infection. The snails were kept in outdoor aquaria in order to simulate the natural temperature conditions in the endemic bilharziasis areas of Iran.The results showed that the cercarial-incubation periods of these two schistosome species varied with the environmental water temperature. Snails exposed in August had the shortest incubation period, and snails exposed in November the longest. The cercarial-incubation period for S. haematobium was longer than that for S. bovis in all months. The difference between the cercarial-incubation period of these two species varied from three to 18 days, being greater in the winter than in the summer.It has been concluded that the low temperature of the water in the winter retards the development of miracidia into cercariae and that the winter is therefore the poorest season for potential transmission. In summer, in spite of the hot weather, snails may still shed cercariae, but spring and autumn are the optimum seasons for cercariae transmission.

Progress in the national schistosomiasis control programme of Iran.

A combination of chemotherapy and mollusciciding has been used in Khuzestan, south-west Iran, since 1966, to try to control urinary schistosomiasis. The total amount of molluscicide used each year varied between 702 and 3505 kg and between 287 and 1320 infected persons were detected and treated annually. The prevalence of infection has gradually declined from 8.3% in 1970 to 0.7% in 1979. Similarly, the incidence of infection among schoolchildren decreased from 3.5% in 1970 to 0.7% in 1979. The proportion of Bulinus-infested habitats also decreased from 10% in 1971 to 2.4% in 1979.

Helminth parasites of the wild boar, Sus scrofa, in Luristan province, western Iran and their public health significance.

Seven helminth species were obtained from 12 wild boars (Sus scrofa) during a survey from 2000 to 2001 in Luristan province, western Iran. These species include the cestode larvae Cysticercus tenuicollis (25%), C. cellulosae (8.3%), the nematodes Metastrongylus apri (41.6%), M. pudendotectus (16.6%), M. salmi (8.3%), Trichuris suis (8.3%) and the acanthocephalan Macracanthorhynchus hirudinaceus (41.6%). No trematodes were found. Seven wild boars (58.3%) were identified as having at least one helminth species. A single infection was detected in 16.6% of cases, but a three species infection covered the highest rank (25%). All these helminths have been reported from other areas of Iran including the north, northeast and southwest, but not in Luristan. Among seven helminths identified, at least three species are transmissible to humans. The public health significance of these helminths is discussed.

Human and animal fascioliasis in Mazandaran province, northern Iran.

The fascioliasis situation in humans and livestock of Iranian Mazandaran is analysed for the first time. Coprological studies showed 7.3% and 25.4% global prevalences in sheep and cattle, respectively. Studies in slaughterhouses indicate that sheep and cattle may be the main reservoir species, buffaloes may play local roles in the transmission, and goats and horses probably only participate sporadically. Morphometric studies by computer image analysis showed that forms intermediate between Fasciola hepatica and F. gigantica appear in addition to both species. A total of 107 infected humans were diagnosed during the 1999-2002 period, which suggests that fascioliasis may be widespread. The absence of differences in human fascioliasis among gender and age groups differs from other human endemic areas. Both human and animal infections show marked differences between western and eastern Mazandaran. Traditions in herbal condiments for human consumption, methods of animal husbandry and annual rainfall may explain the higher prevalences in western Mazandaran.