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  1. Article ; Online: Natural Trypanosoma cruzi Infection and Climatic Season Influence the Developmental Capacity in Field-Caught Mepraia spinolai Nymphs

    Juan Botzotz / Gabriel Méndez-Valdés / Sylvia Ortiz / Angélica López / Carezza Botto-Mahan / Aldo Solari

    Insects, Vol 14, Iss 272, p

    2023  Volume 272

    Abstract: In this study, we evaluated the effect of the climatic season and infection by Trypanosoma cruzi , etiological agent of Chagas disease, on the molting capacity of the triatomine vector Mepraia spinolai endemic to Chile. We used wild-caught first-to- ... ...

    Abstract In this study, we evaluated the effect of the climatic season and infection by Trypanosoma cruzi , etiological agent of Chagas disease, on the molting capacity of the triatomine vector Mepraia spinolai endemic to Chile. We used wild-caught first-to-fourth instar nymphs during cooling (fall and winter) and warming (spring) periods. After capturing, nymphs were fed at the laboratory, and maintained under optimal rearing conditions. Feeding was repeated 40 days later. We followed-up the molting events on 709 nymphs, recording one, two or the absence of molts after two feeding opportunities. Within the same climatic period, only infected second- and fourth-instar nymphs from the warming period showed a larger proportion of double molting compared to uninfected nymphs. Regarding the climatic period, infected and uninfected first- and fourth-instar nymphs exhibited a larger proportion of double molting in the warming and cooling periods, respectively. The pattern of non-molting nymph occurrence suggests they probably reach diapause by environmental stochasticity. The effect of the climatic period and T. cruzi infection on the development of M. spinolai is an instar-dependent phenomenon, highlighting the occurrence of finely synchronized processes at different moments of the life cycle of such an hemimetabolous insect as triatomines.
    Keywords Mepraia spinolai ; Trypanosoma cruzi ; instar-dependent molting ; sylvatic kissing bug ; Chagas disease vector ; molting efficiency ; Science ; Q
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Trypanosoma cruzi infection follow-up in a sylvatic vector of Chagas disease

    Valeria Cortés / Amalia Cruz / Sofia Onetti / Daniela Kinzel / Javiera Garcia / Sylvia Ortiz / Angélica Lopez / Pedro E Cattan / Carezza Botto-Mahan / Aldo Solari

    PLoS Neglected Tropical Diseases, Vol 15, Iss 9, p e

    Comparing early and late stage nymphs.

    2021  Volume 0009729

    Abstract: Chagas disease is caused by Trypanosoma cruzi and transmitted by the triatomine Mepraia spinolai in the southwest of South America. Here, we examined the T. cruzi-infection dynamics of field-caught M. spinolai after laboratory feeding, with a follow-up ... ...

    Abstract Chagas disease is caused by Trypanosoma cruzi and transmitted by the triatomine Mepraia spinolai in the southwest of South America. Here, we examined the T. cruzi-infection dynamics of field-caught M. spinolai after laboratory feeding, with a follow-up procedure on bug populations collected in winter and spring of 2017 and 2018. Bugs were analyzed twice to evaluate T. cruzi-infection by PCR assays of urine/fecal samples, the first evaluation right after collection and the second 40 days after the first feeding. We detected bugs with: the first sample positive and second negative (+/-), the first sample negative and second positive (-/+), and with both samples positive or negative (+/+; -/-). Bugs that resulted positive on both occasions were the most frequent, with the exception of those collected in winter 2018. Infection rate in spring was higher than winter only in 2018. Early and late stage nymphs presented similar T. cruzi-infection rates except for winter 2017; therefore, all nymphs may contribute to T. cruzi-transmission to humans. Assessment of infection using two samples represents a realistic way to determine the infection a triatomine can harbor. The underlying mechanism may be that some bugs do not excrete parasites unless they are fed and maintained for some time under environmentally controlled conditions before releasing T. cruzi, which persists in the vector hindgut. We suggest that T. cruzi-infection dynamics regarding the three types of positive-PCR results detected by follow-up represent: residual T. cruzi in the rectal lumen (+/-), colonization of parasites attached to the rectal wall (-/+), and presence of both kinds of flagellates in the hindgut of triatomines (+/+). We suggest residual T. cruzi-infections are released after feeding, and result 60-90 days after infection persisting in the rectal lumen after a fasting event, a phenomenon that might vary between contrasting seasons and years.
    Keywords Arctic medicine. Tropical medicine ; RC955-962 ; Public aspects of medicine ; RA1-1270
    Subject code 630
    Language English
    Publishing date 2021-09-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article: Fluctuations in Trypanosoma cruzi discrete typing unit composition in two naturally infected triatomines: Mepraia gajardoi and M. spinolai after laboratory feeding

    Egaña, Camila / Aldo Solari / Fernanda Vergara / Raquel Pinto / Ricardo Campos / Sylvia Ortiz

    Acta tropica. 2016 Aug., v. 160

    2016  

    Abstract: Mepraia species are hematophagous insects and the most important wild vectors of Trypanosoma cruzi, the causative agent of Chagas disease in southeastern South America. Because the domestic Triatoma infestans is already controlled, the transmission of ... ...

    Abstract Mepraia species are hematophagous insects and the most important wild vectors of Trypanosoma cruzi, the causative agent of Chagas disease in southeastern South America. Because the domestic Triatoma infestans is already controlled, the transmission of different T. cruzi discrete typing units (DTUs) by Mepraia species deserves attention. Our aim is to gather information on the diversity of T. cruzi DTUs circulating in natural insect populations.Two groups of naturally infected bugs 21 Mepraia gajardoi and 26 Mepraia spinolai were followed-up after two or more laboratory feedings by means of minicircle-PCR assays to evaluate the composition of four T. cruzi DTUs by hybridization tests. Fluctuations from positive T. cruzi detection to negative and the converse, as well as single to mixed infections with different T. cruzi DTUs and the opposite were frequent observations after laboratory feeding in both Mepraia species. Single and mixed infections with more than two T. cruzi DTUs were detected after the first feeding; however mainly mixed infections prevailed after the second feeding. Laboratory feeding on three or more occasions resulted in a decreasing trend of the parasite burden. In a comparison with 28 infected and fed M. gajardoi collected one year before from the same vector colony T. cruzi DTUs composition changed, indicating that temporal variations occur in T. cruzi.Natural populations of Mepraia species can transmit complex mixtures T. cruzi DTUs which fluctuate over time after feeding, with a tendency to eliminate the parasitism after prolonged feeding.
    Keywords Chagas disease ; hematophagous insects ; hybridization ; mixed infection ; parasitism ; temporal variation ; Triatoma infestans ; Trypanosoma cruzi ; South America
    Language English
    Dates of publication 2016-08
    Size p. 9-14.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 210415-5
    ISSN 1873-6254 ; 0001-706X
    ISSN (online) 1873-6254
    ISSN 0001-706X
    DOI 10.1016/j.actatropica.2016.04.008
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Comparing vector competence of Mepraia gajardoi and Triatoma infestans by genotyping Trypanosoma cruzi discrete typing units present in naturally infected Octodon degus

    Sandoval-Rodríguez, Alejandra / Gemma Rojo / Angélica López / Sylvia Ortiz / Miguel Saavedra / Carezza Botto-Mahan / Pedro E. Cattan / Aldo Solari

    Acta tropica. 2019 Feb., v. 190

    2019  

    Abstract: Chagas disease is a vector-borne disease caused by the parasite Trypanosoma cruzi, and transmitted by triatomine insects to several mammal species. In Chile, the wild triatomine species are the endemic Mepraia species, and the only domestic vector of ... ...

    Abstract Chagas disease is a vector-borne disease caused by the parasite Trypanosoma cruzi, and transmitted by triatomine insects to several mammal species. In Chile, the wild triatomine species are the endemic Mepraia species, and the only domestic vector of Chagas disease is Triatoma infestans. The aim of this study was to determine the competence of M. gajardoi compared to T. infestans as a T. cruzi vector using the naturally infected rodent Octodon degus. M. gajardoi amplified T. cruzi present in all O. degus studied while T. infestans only in half of the infected rodents. Both triatomine species excrete metacyclic trypomastigotes and amplified the same three T. cruzi DTUs, however, M. gajardoi showed differences in their ability to amplify TcI. TcV and TcVI had the same probability to be amplified by both triatomine species. Both species amplified mixed infections, with TcI-TcVI as the most represented. This study reports the higher vector competence of M. gajardoi in comparison to T. infestans.
    Keywords Chagas disease ; Octodon degus ; Triatoma infestans ; Trypanosoma cruzi ; genotyping ; insects ; mixed infection ; parasites ; probability ; rodents ; trypomastigotes ; vector competence ; vector-borne diseases ; Chile
    Language English
    Dates of publication 2019-02
    Size p. 119-122.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 210415-5
    ISSN 1873-6254 ; 0001-706X
    ISSN (online) 1873-6254
    ISSN 0001-706X
    DOI 10.1016/j.actatropica.2018.11.007
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Spatio-temporal characterization of Trypanosoma cruzi infection and discrete typing units infecting hosts and vectors from non-domestic foci of Chile.

    Camila Ihle-Soto / Eduardo Costoya / Juana P Correa / Antonella Bacigalupo / Berenice Cornejo-Villar / Viviana Estadella / Aldo Solari / Sylvia Ortiz / Héctor J Hernández / Carezza Botto-Mahan / David E Gorla / Pedro E Cattan

    PLoS Neglected Tropical Diseases, Vol 13, Iss 2, p e

    2019  Volume 0007170

    Abstract: BACKGROUND:Trypanosoma cruzi is a protozoan parasite that is transmitted by triatomine vectors to mammals. It is classified in six discrete typing units (DTUs). In Chile, domestic vectorial transmission has been interrupted; however, the parasite is ... ...

    Abstract BACKGROUND:Trypanosoma cruzi is a protozoan parasite that is transmitted by triatomine vectors to mammals. It is classified in six discrete typing units (DTUs). In Chile, domestic vectorial transmission has been interrupted; however, the parasite is maintained in non-domestic foci. The aim of this study was to describe T. cruzi infection and DTU composition in mammals and triatomines from several non-domestic populations of North-Central Chile and to evaluate their spatio-temporal variations. METHODOLOGY/PRINCIPAL FINDINGS:A total of 710 small mammals and 1140 triatomines captured in six localities during two study periods (summer/winter) of the same year were analyzed by conventional PCR to detect kDNA of T. cruzi. Positive samples were DNA blotted and hybridized with specific probes for detection of DTUs TcI, TcII, TcV, and TcVI. Infection status was modeled, and cluster analysis was performed in each locality. We detected 30.1% of overall infection in small mammals and 34.1% in triatomines, with higher rates in synanthropic mammals and in M. spinolai. We identified infecting DTUs in 45 mammals and 110 triatomines, present more commonly as single infections; the most frequent DTU detected was TcI. Differences in infection rates among species, localities and study periods were detected in small mammals, and between triatomine species; temporally, infection presented opposite patterns between mammals and triatomines. Infection clustering was frequent in vectors, and one locality exhibited half of the 21 clusters found. CONCLUSIONS/SIGNIFICANCE:We determined T. cruzi infection in natural host and vector populations simultaneously in a spatially widespread manner during two study periods. All captured species presented T. cruzi infection, showing spatial and temporal variations. Trypanosoma cruzi distribution can be clustered in space and time. These clusters may represent different spatial and temporal risks of transmission.
    Keywords Arctic medicine. Tropical medicine ; RC955-962 ; Public aspects of medicine ; RA1-1270
    Subject code 590
    Language English
    Publishing date 2019-02-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: Simple methodology to directly genotype Trypanosoma cruzi discrete typing units in single and mixed infections from human blood samples

    Bontempi, Iván A / Aldo Solari / Cristina Diez / Diana Fabbro / María L. Bizai / Silvia Manattini / Sylvia Ortiz

    Infection, genetics, and evolution. 2016 Sept., v. 43

    2016  

    Abstract: Different DNA markers to genotype Trypanosoma cruzi are now available. However, due to the low quantity of parasites present in biological samples, DNA markers with high copy number like kinetoplast minicircles are needed. The aim of this study was to ... ...

    Abstract Different DNA markers to genotype Trypanosoma cruzi are now available. However, due to the low quantity of parasites present in biological samples, DNA markers with high copy number like kinetoplast minicircles are needed. The aim of this study was to complete a DNA assay called minicircle lineage specific-PCR (MLS-PCR) previously developed to genotype the T. cruzi DTUs TcV and TcVI, in order to genotype DTUs TcI and TcII and to improve TcVI detection. We screened kinetoplast minicircle hypervariable sequences from cloned PCR products from reference strains belonging to the mentioned DTUs using specific kDNA probes. With the four highly specific sequences selected, we designed primers to be used in the MLS-PCR to directly genotype T. cruzi from biological samples. High specificity and sensitivity were obtained when we evaluated the new approach for TcI, TcII, TcV and TcVI genotyping in twenty two T. cruzi reference strains. Afterward, we compared it with hybridization tests using specific kDNA probes in 32 blood samples from chronic chagasic patients from North Eastern Argentina. With both tests we were able to genotype 94% of the samples and the concordance between them was very good (kappa=0.855). The most frequent T. cruzi DTUs detected were TcV and TcVI, followed by TcII and much lower TcI. A unique T. cruzi DTU was detected in 18 samples meantime more than one in the remaining; being TcV and TcVI the most frequent association. A high percentage of mixed detections were obtained with both assays and its impact was discussed.
    Keywords blood sampling ; genetic markers ; genotype ; genotyping ; humans ; kinetoplast DNA ; mixed infection ; parasites ; patients ; polymerase chain reaction ; Trypanosoma cruzi ; Argentina
    Language English
    Dates of publication 2016-09
    Size p. 123-129.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 2037068-4
    ISSN 1567-1348
    ISSN 1567-1348
    DOI 10.1016/j.meegid.2016.05.026
    Database NAL-Catalogue (AGRICOLA)

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  7. Article: Within-host temporal fluctuations of Trypanosoma cruzi discrete typing units: the case of the wild reservoir rodent Octodon degus

    Rojo, Gemma / Alejandra Sandoval-Rodríguez / Angélica López / Sylvia Ortiz / Juana P. Correa / Miguel Saavedra / Carezza Botto-Mahan / Pedro E. Cattan / Aldo Solari

    Parasites & vectors. 2017 Dec., v. 10, no. 1

    2017  

    Abstract: BACKGROUND: Chagas disease caused by Trypanosoma cruzi is considered a major public health problem in America. After an acute phase the disease changes to a chronic phase with very low parasitemia. The parasite presents high genetic variability with ... ...

    Abstract BACKGROUND: Chagas disease caused by Trypanosoma cruzi is considered a major public health problem in America. After an acute phase the disease changes to a chronic phase with very low parasitemia. The parasite presents high genetic variability with seven discrete typing units (DTUs): TcI-TcVI and Tc bat. The aim of this work is to evaluate fluctuation of parasitemia and T. cruzi DTUs in naturally infected Octodon degus. METHODS: After animal capture parasitemia was obtained by qPCR and later the animals were evaluated by three serial xenodiagnoses using two insect vector species, Mepraia spinolai and Triatoma infestans. The parasites amplified over time by insect xenodiagnosis were analyzed by conventional PCR and after that the infective T. cruzi were characterized by means of hybridization tests. RESULTS: The determination of O. degus parasitemia before serial xenodiagnosis by qPCR reveals a great heterogeneity from 1 to 812 parasite equivalents/ml in the blood stream. The T. cruzi DTU composition in 23 analyzed animals by xenodiagnosis oscillated from mixed infections with different DTUs to infections without DTU identification or vice versa, this is equivalent to 50% of the studied animals. Detection of triatomine infection and composition of T. cruzi DTUs was achieved more efficiently 40 days post-infection rather than after 80 or 120 days. CONCLUSION: Trypanosoma cruzi DTUs composition fluctuates over time in naturally infected O. degus. Three replicates of serial xenodiagnosis confirmed that living parasites have been studied. Our results allow us to confirm that M. spinolai and T. infestans are equally competent to maintain T. cruzi DTUs since similar results of infection were obtained after xenodiagnosis procedure.
    Keywords Chagas disease ; Chiroptera ; Octodon degus ; Triatoma infestans ; Trypanosoma cruzi ; blood flow ; capture of animals ; genetic variation ; hybridization ; insect vectors ; mixed infection ; parasitemia ; parasites ; public health ; quantitative polymerase chain reaction ; rodents ; xenodiagnosis
    Language English
    Dates of publication 2017-12
    Size p. 380.
    Publishing place BioMed Central
    Document type Article
    ZDB-ID 2409480-8
    ISSN 1756-3305
    ISSN 1756-3305
    DOI 10.1186/s13071-017-2314-2
    Database NAL-Catalogue (AGRICOLA)

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  8. Article: Temporal variation in Trypanosoma cruzi lineages from the native rodent Octodon degus in semiarid Chile

    Botto-Mahan, Carezza / Aldo Solari / Alejandra Sandoval-Rodríguez / Fabiola Peña / Gemma Rojo / Sylvia Ortiz

    Acta tropica. 2015 Nov., v. 151

    2015  

    Abstract: Chagas disease is a zoonosis caused by the protozoan parasite Trypanosoma cruzi and transmitted by triatomine insects to several mammalian species acting as reservoir hosts. In the present study, we assess T. cruzi-prevalence and DTU composition of the ... ...

    Abstract Chagas disease is a zoonosis caused by the protozoan parasite Trypanosoma cruzi and transmitted by triatomine insects to several mammalian species acting as reservoir hosts. In the present study, we assess T. cruzi-prevalence and DTU composition of the endemic rodent Octodon degus from a hyper-endemic area of Chagas disease in Chile. Parasite detection is performed by PCR assays on blood samples of individuals captured in the austral summers of 2010–2013. The infection level in rodents differed in the summers of these four years between 18% and 70%. Overall, infected O. degus showed similar T. cruzi-DTU composition (TcI, TcII, TcV and TcVI lineages) among years, corresponding to single and mixed infection, but the relative importance of each DTU changed among years. In 2013, we detected that only three out of the four T. cruzi-DTU found in O. degus were present in the endemic triatomine Mepria spinolai. We suggest that O. degus, an abundant long-lived rodent, is an important native reservoir of T. cruzi in the wild transmission cycle of Chagas disease and it is able to maintain all the T. cruzi-DTUs described in semiarid Chile.
    Keywords blood sampling ; Chagas disease ; disease reservoirs ; insects ; mixed infection ; Octodon degus ; parasites ; polymerase chain reaction ; rodents ; summer ; temporal variation ; Triatominae ; Trypanosoma cruzi ; zoonoses ; Chile
    Language English
    Dates of publication 2015-11
    Size p. 178-181.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 210415-5
    ISSN 1873-6254 ; 0001-706X
    ISSN (online) 1873-6254
    ISSN 0001-706X
    DOI 10.1016/j.actatropica.2015.06.008
    Database NAL-Catalogue (AGRICOLA)

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  9. Article ; Online: Phylogenetic analysis of Bolivian bat trypanosomes of the subgenus schizotrypanum based on cytochrome B sequence and minicircle analyses.

    Lineth García / Sylvia Ortiz / Gonzalo Osorio / Mary Cruz Torrico / Faustino Torrico / Aldo Solari

    PLoS ONE, Vol 7, Iss 5, p e

    2012  Volume 36578

    Abstract: The aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of Bolivian Carollia bats. Eighteen cloned stocks were isolated from 115 bats belonging to Carollia perspicillata (Phyllostomidae) from three ... ...

    Abstract The aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of Bolivian Carollia bats. Eighteen cloned stocks were isolated from 115 bats belonging to Carollia perspicillata (Phyllostomidae) from three Amazonian areas of the Chapare Province of Bolivia and studied by xenodiagnosis using the vectors Rhodnius robustus and Triatoma infestans (Trypanosoma cruzi marenkellei) or haemoculture (Trypanosoma dionisii). The PCR DNA amplified was analyzed by nucleotide sequences of maxicircles encoding cytochrome b and by means of the molecular size of hyper variable regions of minicircles. Ten samples were classified as Trypanosoma cruzi marinkellei and 8 samples as Trypanosoma dionisii. The two species have a different molecular size profile with respect to the amplified regions of minicircles and also with respect to Trypanosoma cruzi and Trypanosoma rangeli used for comparative purpose. We conclude the presence of two species of bat trypanosomes in these samples, which can clearly be identified by the methods used in this study. The presence of these trypanosomes in Amazonian bats is discussed.
    Keywords Medicine ; R ; Science ; Q
    Subject code 500
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Vertical transmission of Trypanosoma cruzi in the Province of Choapa, IV Region, Chile

    Werner Apt / Inés Zulantay / Aldo Solari / Sylvia Ortiz / David Oddo / Gabriela Corral / Carine Truyens / Yves Carlier

    Biological Research, Vol 43, Iss 3, Pp 269-

    Preliminary Report (2005-2008)

    2010  Volume 274

    Abstract: Congenital Chagas disease acquired special importance in Chile after the certification of the control of Triatoma infestans and transmission by blood donors affected with Trypanosoma cruzi. In order to establish adequate protocols for intervention and ... ...

    Abstract Congenital Chagas disease acquired special importance in Chile after the certification of the control of Triatoma infestans and transmission by blood donors affected with Trypanosoma cruzi. In order to establish adequate protocols for intervention and control in infected mother-neonate pairs in endemic zones of Chagas disease, we present partial results (2005-2008) of a pilot project which is being carried out in the Province of Choapa, IV Region, Chile, whose objectives are: determine the current prevalence of the disease in pregnant women, estimate the incidence of vertical transmission of T. cruzi to newborns, determine the lineages of the parasite present in mothers who do and do not transmit the disease, determine the prevalence of Chagas disease in maternal grandmothers of neonates and study placental histopathology. Preliminary results indicated that in this study period, 3.7% of the women who gave birth in the Province have Chagas disease and 2.5% of their newborns were infected. The most frequent T. cruzi genotypes found in mothers studied during pregnancy were TCI and TCIId, either alone or in mixed infections. A high percentage (74.3%) of the grandmothers studied was infected with the parasite. In 29 placentas from mothers with Chagas disease we observed edema, necrosis, fibrinoid deposits and slight lymphoplasmocyte infiltration. In three placentas we found erythroblastosis and in one of them amastigote forms of T. cruzi; this was one of the cases of congenital infection. The evaluation of the diagnostic and control protocols generated will allow us to determine if it has been possible to modify the natural history of vertical transmission of T. cruzi in Chile.
    Keywords Congenital Chagas disease ; Province of Choapa ; multidisciplinary study ; Biology (General) ; QH301-705.5
    Subject code 610
    Language English
    Publishing date 2010-01-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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