Aeration effect on Spirulina platensis growth and ã-linolenic acid production

The influence of aeration on algal growth and gamma-linolenic acid (GLA) production in a bubble column photobioreactor was investigated. Studies were performed in a 20-L reactor at different aeration rates (0.2-2.5 vvm). Static, continuous, and periodic operation of air resulted in 41.9%, 88.4%, and 108% air saturation of dissolved oxygen, for which the corresponding values of GLA were 2.3, 6.5, and 7.5 mg·g-1 dry cell weight, respectively. An increase in the aeration rate from 0.2 to 2.5 vvm enhanced both the specific growth rate and GLA content under periodic sparging in the bicarbonate medium. With a 6-fold increase in the aeration rate, the GLA content of the alga increased by 69.64% (5.6-9.5 mg· g-1 dry cell weight). In addition, the total fatty acid (TFA) content in dry biomass increased from 2.22% to 4.41%, whereas the algae maintained a constant GLA to TFA ratio within the aeration rate tested. The dependence of GLA production on the aeration rate was explained by interrelating the GLA production rate with the specific growth rate using the Luedeking and Piret mixed growth model.

Análise parasitológica em esgotos tratados utilizados na agricultura / Parasitological analysis in treated sewage used in agriculture

A diminuição da disponibilidade de água de boa de qualidade em nível mundial é resultado, entre outros fatores, do consumo elevado exercido pela agricultura irrigada. A fim de minimizar os impactos ocasionados por essa atividade aos recursos hídricos, muitos países demonstram a viabilidade do emprego de efluentes de esgoto tratado na agricultura. Contudo, esta prática oferece riscos à saúde pública através dos organismos patogênicos capazes de sobreviver no esgoto. Entre estes patógenos a OMS destaca os protozoários e os helmintos parasitas do homem, pelo fato de apresentarem maior período de sobrevivência em condições adversas e alto poder de infecção. O presente trabalho tem como objetivo realizar um levantamento qualitativo e quantitativo dos parasitas intestinais de importância sanitária presentes no esgoto afluente, no efluente tratado e no efluente desinfetado de duas estações de tratamento localizadas na cidade de Piracicaba. A ETE Cecap é composta por um sistema australiano com uma lagoa anaeróbia, lagoas facultativas primária e secundária e tratamento por filtração e desinfecção por cloração. A ETE Piracicamirim é constituída por reatores UASB seguidos por lagoa aerada, decantadores secundários de lodo ativado, tratamento por filtro de areia e desinfecção por radiação ultravioleta. Entre maio de 2008 e dezembro de 2009 foram coletas amostras do esgoto bruto e dos efluentes tratado e desinfetado, seguindo as orientações de AYRES e MARA (1996). As técnicas de preparo e análises parasitológicas foram realizadas segundo YANKO (1987) e WHO (1999). A ETE Cecap apresentou uma frequência de amostras positivas de 40 por cento para o efluente desinfetado, sendo Toxocara sp o parasita mais presente com 46,17 ovos/l. A média de ovos de helmintos para o período de estudo foi 3,78 ovos/l de efluente desinfetado. A ETE Piracicamirim apresentou uma frequência de 100 por cento para o efluente desinfetado. Ascaris sp foi o parasita mais encontrado nos três pontos...

Decreased availability of good water quality worldwide is a result, among other factors, high consumption exerted by irrigated agriculture. In order to minimize the impacts caused by this activity to water, many countries demonstrate the viability of using treated sewage effluent in agriculture. However, this practice provides a public health risk through the pathogens can survive in sewage. Among these pathogens, WHO stresses the protozoa and helminths of human, because they presented greater period of survival in adverse conditions and high power of infection. This paper aims to evaluate the quality and quantity of intestinal parasites of sanitary importance present in the raw sewage in the treated effluent and disinfected from two treatment plants located in the city of Piracicaba. The sewage treatment plant CECAP comprises an Australian system with an anaerobic pond, facultative ponds primary and secondary treatment by filtration and disinfection by chlorination. The sewage treatment plant Piracicamirim consists of UASB followed by aerated lagoon, activated sludge secondary clarifiers, treatment by sand filter and disinfection by ultraviolet radiation. Between May 2008 and December 2009 were collected and samples of raw sewage effluent treated and disinfected, following the guidelines of AYRES and MARA (1996). The techniques of preparation and analysis were performed according parasitological YANKO (in 1987) and WHO (1999). CECAP showed rates of positive samples of 40 per cent for the effluent disinfected with Toxocara sp parasite more present with 46.17 eggs/l. The mean helminths eggs for the study period was 3.78 eggs/l effluent disinfected. Piracicamirim showed rates of 100 per cent for the effluent disinfected. Ascaris sp was the parasite most commonly found in the three collection sites...

Intestinal Parasitic Infections among Inhabitants of Karaj City, Tehran Province, Iran in 2006-2008

Karaj is an area with large influx of refugee people in Iran. To increase knowledge about parasitic infections, we carried out this research during 2006-2008. We recorded the stool examination results and some of their personal characteristics. A total of 13,915 human stools were examined, and 649 (4.7%) were positive for intestinal parasites. Among them, 13 (0.09%) had worm and 636 (4.6%) had protozoan infections. Maximum infections belonged to Giardia intestinalis, and 534 (3.8%) samples had this infection. Other parasitic infections included Entamoeba coli (0.39%), Entamoeba histolytica (0.021%), Blastocystis hominis (0.08%), Trichomonas hominis (0.1%), Iodamoeba butschlii (0.06%), Chilomastix mesnili (0.007%), Endolimax nana (0.05%), Enterobius spp. eggs (0.028%), Taenia proglottids (0.028%), and Strongyloides stercoralis larvae (0.03%). The maximum numbers of referred people to laboratories were in July and the maximum percentage of infections was in August. There is a point that all 5 Strongyloides stercoralis infections were pertained to 2008. With attention to the rate of parasitic infections (4.7%), it seems that we should take additional educational information to wide spectrum of people living in this city.

A Survey of Intestinal Protozoan Infections among Gastroenteritis Patients during a 3-Year Period (2004-2006) in Gyeonggi-do (Province), South Korea

The incidence and etiology of parasite-associated gastroenteritis during 2004-2006 in Gyeonggi-do (province), South Korea was determined by means of antigen detection ELISA on 6,071 stool specimens collected from 6 general hospitals. At least 1 parasitic agent was detected in 3.4% (208/6,071) of the stool samples. Among these, Giardia lamblia was the most numerous (152 cases; 2.5%), followed by Entamoeba histolytica (25 cases; 0.4%), Cryptosporidium parvum (23 cases; 0.4%), and mixed infections (8 cases; 0.1%). Patients aged 1-5 years had the largest proportion (69.2%; 144/208) of parasite-positive stool specimens. Parasite-mediated gastroenteritis was most common from June to September. The detection rate gradually increased from 2004 to 2006. This study shows that parasite-mediated gastroenteritis may be significant among children in Korea and that parasite infection surveillance should be constantly performed.

A Laboratory-Based Study for First Documented Case of Urinary Myiasis Caused by Larvae of Megaselia scalaris (Diptera: Phoridae) in Saudi Arabia

Megaselia scalaris (Diptera: Phoridae) is one of the medically important insects. Maggots from a urine sample of a 5-year-old Saudi girl were examined microscopically for identification. These maggots were cultured to become adult flies. Larvae and adults were identified using standard keys. Protozoan flagellates were obtained from the gut of the larvae. This is the first report of M. scalaris as a causative agent of urinary human myiasis in Saudi Arabia.

A Laboratory-Based Study for First Documented Case of Urinary Myiasis Caused by Larvae of Megaselia scalaris (Diptera: Phoridae) in Saudi Arabia

Megaselia scalaris (Diptera: Phoridae) is one of the medically important insects. Maggots from a urine sample of a 5-year-old Saudi girl were examined microscopically for identification. These maggots were cultured to become adult flies. Larvae and adults were identified using standard keys. Protozoan flagellates were obtained from the gut of the larvae. This is the first report of M. scalaris as a causative agent of urinary human myiasis in Saudi Arabia.

Canine parasitic zoonoses in Bangkok temples.

Fecal samples were collected from 204 humans and 229 dogs from 20 different temples in Bangkok, as well as communities in the surrounding temple ground areas. Human and dog stool samples were examined for intestinal parasites including Giardia using zinc sulfate flotation and microscopy. Hookworms were the most common parasite in dogs (58.1%) followed by Trichuris (20.5%), Isospora (10%), Giardia (7.9%), Toxocara (7.4%), Dipylidium caninum (4.4%) and Spirometra (3.1%). Blastocystis hominis (5.9%) was the most common parasite in humans followed by hookworms (3.4%), Giardia (2.5%), Strongyloides (2%) and Cryptosporidium (1.5%). All samples microscopy-positive for Giardia were genotyped. The majority of Giardia isolated from the dog population was placed in Assemblage A, followed by Assemblages D, B and C, respectively, while human isolates were placed in Assemblages A and B. Therefore, dogs in temple communities posed a potential zoonotic risk to humans for transmission of hookworms, Giardia (especially Assemblage A genotypes) and Toxocara canis.

Características do fluído ruminal de ovinos Santa Inês criados extensivamente em Pernambuco / Ruminal fluid characteristics of Santa Inês sheep under pasture conditions in the State of Pernambuco

The objective of this study was to determine normal standards to ruminal fluid characteristics of Santa Inês sheep under pasture conditions in the State of Pernambuco. Fifty samples were collected, using an esophageal tube, during winter (rainy season) and summer (dry season). The predominant colors were an olive green in the rainy season and a nut-brown in the dry season. The smell was aromatic, but was stronger in winter. A slight viscous consistence was found in most of the samples, with a greater proportion in winter. The sedimentation and flotation time was 6.73min (±1.63) in the rainy period and 3.15min (±0.72) in the dry period. In the biochemical tests, the average values found in winter and summer were, respectively: pH 6.76±0.21 and 6,59±0.14; methylene blue reduction, 3.20min (±0.76) and 7.76min (±3.00); chloride, 28.14±4,16mEq/L and 24.97±5.65mEq/L; acidity, 21.90±4.38UC and 13.68±2.97UC. Ruminal microbiotic analyses revealed abundant and moderate density of protozoa in winter and summer, respectively. The motility was very active and there were almost 90 percent of live protozoa in both seasons. Protozoa numbers were 425.373±217.258/mL in winter and 155.375±83.113/mL in summer. There was a mixed population of bacteria with prevalence of Gram-negative forms in both seasons.

Este trabalho teve por objetivo estabelecer padrões de normalidade para as características do fluído ruminal de ovinos da raça Santa Inês criados sob regime extensivo de pastagem no município de Garanhuns, Agreste Meridional de Pernambuco. Foram coletadas amostras de 50 animais, por meio de sonda esofágica, nos períodos de inverno (estação chuvosa) e verão (estação seca). As cores do fluído predominantes foram a verde oliva, no período chuvoso, e a castanha, no período seco. O odor aromático foi observado em todas as amostras, estando mais pronunciado no inverno. A consistência levemente viscosa predominou em ambas as estações, com maior freqüência desta no inverno. O tempo de sedimentação e flotação foi de 6,73min (±1,63) na estação chuvosa e 3,15min (±0.72) na estação seca. Nas provas bioquímicas os valores médios encontrados para o inverno e verão, respectivamente, foram: pH, 6,76±0,21 e 6,59±0,14; redução do azul de metileno, 3,20 min (±0,76) e 7,76min (±3.00); teor de cloretos, 28,14±4,16mEq/L e 24,97±5,65mEq/L; acidez total titulável, 21,90±4,38UC e 13,68±2.97UC. Observou-se densidade abundante (+++) de protozoários no inverno e moderada (++) no verão. A motilidade dos protozoários foi bastante ativa (+++) e havia aproximadamente 90 por cento deles vivos em ambos os períodos experimentais. A contagem de protozoários no inverno foi de 425.373±217.258/mL e 155.375± 83.113/mL no verão. As bactérias Gram-negativas predominaram em ambas as estações.

Diversity of microflora in the gut and casts of tropical composting earthworms reared on different substrates.

The diversity of fungi, bacteria, yeast, actinomycetes and protozoa were analysed in the gut and casts of Eudrilus eugeniae, Lampito mauritii, Eisenia fetida and Perionyx excavatus, both qualitatively and quantitatively as influenced by different feed substrates like clay loam soil, cowdung and pressmud. While actinomycetes (Streptomyces albus, S. somaliensis, Nocardia asteroides, N. caviae and Saccharomonosporia) were not digested by any of these species of worms, protozoa (Amoeba proteus, A. terricola, Paramecium trichium, Euglena viridis, E. orientalis, Vorticella picta and Trichomonas hominis) and yeast (Candida tropicalis, C. krusei C. albicans and Cryptococcus neoformans) were totally digested. Certain species of fungi (Saksenae vasiformis, Mucor plumbeus, Cladosporium carrionii, C. herbacium, Alternaria sp., Cunninghamella echinulata, Mycetia sterila, Syncephalostrum racemosum, Curvalaria lunata, C. geniculata and Geotrichum candidum) and bacteria (Pseudomonas aeruginosa, Bacterium antitratum, Mima polymorpha, Enterobacter aerogenes, E. cloacae, Proteus vulgaris, P. mirabilis, P. rettgeri, Escherichia coli, Staphylococus citreus, Bacillus subtilis, B. cereus, Enterococci and Micrococci) were completely digested. Certain other species were not digested fungi like Aspergillus fumigatus, A. flavus, A. ochraceous, Trichoderma koningii (except by Eeugeniae), Fusarium moniliforme (except by E. eugeniae) and Rhizopus sp., and bacteria like Klebsiella pneumoniae and Morganella morganii) and these were multiplied during the transit of the organic residues through the gut of worms. The microbial proliferation was more in the casts, due to the environment prevailing--rich in nutrient supply and large surface area available for growth and reproduction of the microbes that lead to enhanced microbial activity and humic acid contents in the casts.

Alternativas nutricionais para o crescimento primário in vitro e para a identificação de protozoários do gênero leishmania

Introdução. O crescimento primário e a proliferação de Leishmania são ferramentas valiosas para estudos sobre desenvolvimento e padronização de técnicas diagnósticas, identificação, classificação, análise bioquímica, análise molecular, biologia celular, insumos imunológicos e quimioterápicos. Objetivos: a) estudar diferentes formulações e suplementações de meios de cultura para o crescimento primário de Leishmania; b) avaliar a criopreservação como alternativa para preservar amostras biológicas para o crescimento primário de Leishmania. Materiais e métodos. Meios de cultura: a. bifásico com fase sólida de ágarsangue (BAB) e fase líquida de infusão de cérebro e coração (BHI), TGGY-1 (nova formulação) e solução de uréia-creatinina-sódio-potássio a 5% (UCNaK); b. monofásico: novos meios líquidos TGGY-1 e TGGY-2.Suplementos: urina humana estéril; urina canina estéril; solução de UCNaK a 5%; ácido fólico e hemina. Amostras: a) aspirado de baço de 51 cães de áreas endêmicas para Leishmaniose Visceral canina para os experimentos de crescimento primário e para a identificação de Leishmania spp; b) cepas de referência de Leishmania (L.) chagasi, L. (L.) amazonensis, L. (V.)braziliensis e Trypanosoma (S.)cruzi para os experimentos de proliferação; Resultados e conclusões. Exceção feita à solução UCNaK a 5% todas asdemais formulações avaliadas permitiram o crescimento primário de Leishmania spp., isoladas de 27 (52,9%) cães examinados. O melhor desempenho foi obtido com o meio bifásico BAB-BHI. Nos experimentos sobre proliferação parasitária, o crescimento exponencial foi obtido nas formulações BAB-BHI com diferentes suplementos; BAB-TGGY-1; TGGY-1 e TGGY-2 com hemina e ácido fólico. A criopreservação da amostra de 6 aspirado de baço apresentou-se como alternativa viável para...

Pathogenesis and pathology of brain abscess.

Brain abscess continues to be a serious medical problem with increasing incidence despite advances in diagnostic and surgical methods, and advent of new antibiotics. This is due to increase in immune suppressed individuals, opportunistic pathogens and resistance to antibiotics. The morbidity, mortality and long term sequelae of brain abscess like cognitive impairment and poor neurological outcome are due to persistent release of proinflammatory mediators by activated microglia, astrocytes and infiltrating inflammatory cells, along with disruption of blood brain barrier. Anti-inflammatory drugs along with specific antimicrobial agents help in minimizing damage to the adjacent brain parenchyma. Identification of microorganisms in the aspirated material or the excised specimen help decide the optimal antimicrobial therapy. Prompt examination of smear and meticulous culture techniques to identify aerobes, anerobes, mycobacteria, actinomycetes, parasites and fungi are of utmost importance in choosing antibiotics. Histology complements culture and plays a key role especially in specific infections. Use of appropriate histochemical stains along with tissue reaction helps in diagnosis. The route of spread, the type and virulence of the organism, thickness of the capsule, location and number of abscesses in the brain, and immune status of the host are important determinants of outcome. Identification of microorganisms and insights into pathogenesis allow appropriate therapeutic interventions to improve outcome.

Protozoal contamination of water used in Thai frozen food industry.

This study evaluated the prevalence of contamination of water that was used for food preparation. Since protozoal cysts can be found in small numbers in water, 1,000 liters of either untreated or treated water were filtered through activated carbon block filters (1 microm nominal porosity). Identification of protozoa was performed using specific monoclonal antibodies against Giardia and Cryptosporidium parasites followed by fluorescence microscopy. Twelve of 20 untreated water samples (60%) were found to be contaminated by Giardia cysts, with an average of 53.33 cysts/1,000 liters (geometric mean 39.43), whilst 7 samples (35%) were contaminated by Cryptosporidium oocysts, with an average of 28.57 oocysts/1,000 liters (geometric mean 26.92). Three samples of untreated water (15%) were positive for both organisms. In contrast, none of the treated water samples were contaminated.

Study of bacterial, fungal, and parasitic contaminaiton of currency notes in circulation.

A total of 100 currency notes of various denominations in circulation were randomly studied for bacterial, fungal and protozoal contamination. All except four notes yielded one or more bacteria. Bacterial culture yielded single isolate in 33 notes, two in 44 notes, three in 12 notes and four in 7 notes. The predominant bacterial isolate was Bacillus sps followed by Coagulase negative Staphylococci and Micrococcus sps. Other bacteria that are either potential or confirmed pathogens included K. pneumoniae, E. coli, S. aureus, Pseudomonas sps and S. typhi. Only two notes were positive for Acid fast bacilli. 28 samples did not yield any fungal growth. Overall 118 fungal isolates were isolated, of which 34 could not be identified. All the fungi isolated were saprophytes. Saline and Iodine wet mount did not reveal any parasitic forms. We recommend that currency notes must be handled with caution.

Status of intestinal parasite infections among children in Bat Dambang, Cambodia

A survey was conducted to determine the extent of intestinal parasite infection in Bat Dambang, Cambodia in March 2004. A total of 623 fecal specimens was collected from kindergarten and schoolchildren and examined using the formalin-ether sedimentation technique. The overall infection rate of intestinal parasites was 25.7% (boys, 26.2%; girls, 25.1%), and the infection rates of intestinal helminthes by species were as follows: Echinostoma sp. 4.8%, hookworm 3.4%, Hymenolepis nana 1.3%, and Rhabditis sp. 1.3%. The infection rates of intestinal protozoa were; Entamoeba coli 4.8%, Giardia lamblia 2.9%, Iodamoeba butschlii 1.4%, Entamoeba polecki 1.1%, and Entamoeba histolytica 0.8%. There were no egg positive cases of Ascaris lumbricoides or Trichuris trichiura. All children infected were treated with albendazole, praziquantel, or metronidazole according to parasite species. The results showed that intestinal parasites are highly endemic in Bat Dambang, Cambodia.

Infection status of intestinal parasites in children living in residential institutions in Metro Manila, the Philippines

A small scale survey was performed to know the infection status of intestinal parasite in children of the residential institutions and street communities in Metro Manila, Philippines. A total of 284 stool samples from 11 institutions and 3 street communities was examined by the formalin-ether concentration method. The scotch tape anal swab was adapted to 121 children to investigate the infection status of Enterovius vermicularis. It was found out that 62.0% of the children examined were positive for one or more intestinal parasites. Multiple infections were observed in 34.2% of the children. Among 172 children who gave detail information, the prevalence for Ascaris lumbricoides, Trichuris trichiura, and hookworm was 36.0%, 44.8%, and 7.0% respectively. Of the children examined, 47.7% were found to be harboring parasitic protozoans such as Entamoeba histolytica, Giardia lamblia, and Blastocystis hominis. The most prevalent of these protozoans was B. hominis with an infection rate of 40.7%. The prevalence of these infections among children living in institutions was relatively high. More efforts should be made to implement anthelminthic programs including bi-annual follow-up treatments.

The intestinal parasite infection status of inhabitants in the Roxas city, the Philippines

We carried out a small-scale survey to investigate the status of intestinal protozoa and helminthes infection of inhabitants in Roxas city, Mindoro, the Philippines. Total 301 stool samples were subjected to the formalin-ether concentration method for the detection of helminth ova and protozoan cysts. The overall positive rate was 64.5%, and that of male and female were 56.6% and 72.5%, respectively. The highest infected helminth was Ascaris lumbricoudes (51.2%), followed by Trichuris trichiura (27.6%), hookworm (8.0%) and Enterobius vermicularis (0.3%). The protozoa infection status revealed that Entamoeba coli was the most frequent (15.0%). Iodoamoeba buetschlii and E. histolytica were found but few. The multiple infection more than two parasites was 29.6%, and double infection with A. lumbricoides and T. trichiura was most common. The intestinal helminth infections were highly prevalent in this area, according to this result, and we concluded that anthelminthic drugs should be given to inhabitants, especially to children of 1 to 15 years-old.

First report of the genus Retortamonas (Sarcomastigophora: Retortamonadidae) in birds

In studies carried out on the parasites infecting ostriches (Struthio camelus) in Spain, trophozoites of Retortamonas sp. have been found in the intestinal contents of 28 out of 146 slaughtered ostriches. The species infecting ostriches could not be determined from the morphological data available. However, these findings are important as they constitute the first report of the genus Retortamonas in birds