Revista Brasileira de Saúde e Produção Animal, 2012
Objetivou-se avaliar o consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA), efici... more Objetivou-se avaliar o consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA), eficiência econômica e custo da inclusão do bagaço de mandioca (BM) em dietas de frangos de corte. Para tanto, foram realizados dois experimentos independentes: inicial (1 a 21 dias) e crescimento (22 a 40 dias de idade). O delineamento experimental utilizado foi em blocos casualizados (DBC) com cinco níveis (0; 5; 10; 15 e 20 %) de inclusão de bagaço de mandioca, com oito repetições e 20 aves por unidade experimental. Os resultados do primeiro experimento (1 a 21 dias de idade) mostraram efeito linear negativo da inclusão do bagaço de mandioca sobre o consumo de ração (CR = 1196.2 to 3.46BM, P <0.0008, R² = 0.832). Para o ganho de peso, houve efeito quadrático (GP = 856.506 + 2.372BM - 0,2443BM², P <0.0001, R² = 0.941), fato que o melhorou até o nível de 4,86% de bagaço de mandioca. Não foi encontrada diferença significativa para conversão alimentar. No segundo experimento (22 a 40 dia...
The commercial production of triploids, and the creation of tetraploid broodstock to support it, ... more The commercial production of triploids, and the creation of tetraploid broodstock to support it, has become an important technique in aquaculture of the eastern oyster, Crassostrea virginica. Tetraploids are produced by cytogenetic manipulation of embryos and have been shown to undergo chromosome loss (to become a mosaic) with unknown consequences for breeding. Our objective was to determine the extent of aneuploidy in triploid progeny produced from both mosaic and non-mosaic tetraploids. Six families of triploids were produced using a single diploid female and crossed with three mosaic and non-mosaic tetraploid male oysters. A second set of crosses was performed with the reciprocals. Chromosome counts of the resultant embryos were tallied at 2-4 cell stage and as 6-hour(h)-old embryos. A significant level of aneuploidy was observed in 6-h-old embryos. For crosses using tetraploid males, aneuploidy ranged from 53% to 77% of observed metaphases, compared to 36% in the diploid control. For crosses using tetraploid females, 51%-71% of metaphases were aneuploidy versus 53% in the diploid control. We conclude that somatic chromosome loss may be a regular feature of early development in triploids, and perhaps polyploid oysters in general. Other aspects of chromosome loss in polyploid oysters are also discussed.
Organometallic-cyclodextrin inclusion compounds were obtained by the treatment of molybdenocene d... more Organometallic-cyclodextrin inclusion compounds were obtained by the treatment of molybdenocene dichloride (Cp 2 MoCl 2 ) with the modified cyclodextrins (CDs) heptakis-2,3,6-tri-O-methyl-b-CD (TRIMEB) and 2-hydroxypropyl-b-CD (HPbCD) in aqueous solution. The products were isolated by liophilisation and characterised in the solid-state by powder XRD, thermogravimetric analysis, Raman and FTIR spectroscopy, and 13 C CP MAS NMR spectroscopy. The results are consistent with inclusion of Cp 2 MoCl 2 , rather than hydrolysis products such as [Cp 2 Mo(H 2 O)X] + (X = Cl, OH) or [Cp 2 Mo(H 2 O) 2 ] 2+ . The pure non-included metallocene Cp 2 MoCl 2 and its inclusion compounds with unmodified b-CD, TRIMEB and HPbCD were screened for their potential antiproliferative and cytotoxic activity, in both human cancer and healthy cell lines. Inclusion in CD was found to enhance the cytotoxic effect of Cp 2 MoCl 2 , with the TRIMEB adduct displaying the highest anti-tumour activity, along with the lowest toxicity towards non-neoplastic cells.
A microarray-based analysis was performed with the objective of describing genomic features of oo... more A microarray-based analysis was performed with the objective of describing genomic features of oocytes and looking for potential markers of oocyte quality in the economically important European clam, Ruditapes decussatus. Oocytes of 25 females from Ria de Aveiro, western coast of Portugal (40°42′N; 08°40′W) were selected for this study and oocyte quality was estimated by success of D-larval rate under controlled conditions, which appeared to vary from 0 to 95%. By genome-wide expression profiling with a DNA microarray, 526 probes appeared differentially expressed between two groups representing the largest and smallest value of D larval rates, named good (represented by a mean D-larval yield of 57 ± 22%) and poor (9 ± 5%) quality oocytes. Enrichment analysis showed "lysosome" (dre04142) as the single pathway represented in the enriched KEGG pathway terms, with 8 genes coding for putative cathepsins. Furthermore, differentially expressed genes involved in oocyte protection (DnaJ (Hsp40), Hsp70, cyclophilin B, PDI), maturation (Cam-PDE1C, PRDM9, G protein), sperm-egg interaction (PDI, G protein) and apoptosis (TNF) were also identified. From these, the apoptosis pathway was supposed to assume an important role in oocyte quality as the mRNA level of caspase 8 appeared also negatively correlated with the D-larval yield. Finally, a G-protein transcript was identified as more abundant in poor quality oocytes, which underlines the importance of release prophase I block and meiotic maturation in the oocytes of this species. This study provided new highly valuable information on genes specifically expressed by mature oocytes of R. decussatus, for further understanding of the mechanisms of early development in this species.
The production of Venerupis decussata relies on wild seed collection, which has been recently com... more The production of Venerupis decussata relies on wild seed collection, which has been recently compromised due to recruitment failure and severe mortalities. To address this issue and provide an alternative source of seed, artificial spawning and larval rearing programs were developed. However, hatchery-based seed production is a relatively new industry and it is still underdeveloped. A major hurdle in the European clam seed production is the control of spawning and reproduction, which is further hindered by the impossibility of obtaining fertile gametes by gonadal "stripping", as meiosis re-initiation is constrained to a maturation process along the genital ducts. In the present study, oocytes were collected from 15 females and microarray analyses was performed to investigate gene expression profiles characterizing released and stripped ovarian oocytes. A total of 198 differentially expressed transcripts between stripped and spawned oocytes were detected. Functional analys...
The European clam, Ruditapes decussatus is a species with a high commercial importance in Portuga... more The European clam, Ruditapes decussatus is a species with a high commercial importance in Portugal and other Southern European countries. Its production is almost exclusively based on natural recruitment, which is subject to high annual fluctuations. Increased knowledge of the natural reproductive cycle of R. decussatus and its molecular mechanisms would be particularly important in providing new highly valuable genomic information for better understanding the regulation of reproduction in this economically important aquaculture species. In this study, the transcriptomic bases of R. decussatus reproduction have been analysed using a custom oligonucleotide microarray representing 51,678 assembled contigs. Microarray analyses were performed in four gonadal maturation stages from two different Portuguese wild populations, characterized by different responses to spawning induction when used as progenitors in hatchery. A comparison between the two populations elucidated a specific pathway involved in the recognition signals and binding between the oocyte and components of the sperm plasma membrane. We suggest that this pathway can explain part of the differences in terms of spawning induction success between the two populations. In addition, sexes and reproductive stages were compared and a correlation between mRNA levels and gonadal area was investigated. The lists of differentially expressed genes revealed that sex explains most of the variance in gonadal gene expression. Additionally, genes like Foxl2, vitellogenin, condensing 2, mitotic apparatus protein p62, Cep57, sperm associated antigens 6, 16 and 17, motile sperm domain containing protein 2, sperm surface protein Sp17, sperm flagellar proteins 1 and 2 and dpy-30, were identified as being correlated with the gonad area and therefore supposedly with the number and/or the size of the gametes produced. Citation: de Sousa JT, Milan M, Bargelloni L, Pauletto M, Matias D, et al. (2014) A Microarray-Based Analysis of Gametogenesis in Two Portuguese Populations of the European Clam Ruditapes decussatus. PLoS ONE 9(3): e92202.
The cularines are isoquinoline alkaloids which contain a dihydrooxepine ring system' and occur ma... more The cularines are isoquinoline alkaloids which contain a dihydrooxepine ring system' and occur mainly in the Fumaraceae family.2a Some members are muscle relaxants.2b A number of syntheses of (+)-cularine (la)J and of the isomeric (+)-sarcocapnine2~~ have appeared. (+)-Sarcocapnidine (2b) and 0-demethyl-1 (lb) were obtained in very low yield by the KJ-Fe(CN)6 oxidation of crassifoline .2v4d.f We now report a new 1 (a:
Journal of Experimental Marine Biology and Ecology, 2011
... Joana Teixeira de Sousa a , b , Domitília Matias a , Sandra Joaquim a , Radhouan Ben-Hamadou ... more ... Joana Teixeira de Sousa a , b , Domitília Matias a , Sandra Joaquim a , Radhouan Ben-Hamadou c and Alexandra Leitão a , low asterisk ... assessment of the physiological status of the shellfish populations and is recognized as a useful biomarker (eg [Fernández-Castro and Vido ...
Australian and New Zealand Journal of Obstetrics and Gynaecology, 2009
Women with chronic hypertension are at higher risk of adverse obstetric outcomes. It is essential... more Women with chronic hypertension are at higher risk of adverse obstetric outcomes. It is essential that the condition is identified and evaluated appropriately in early pregnancy. Therefore, an audit has been carried out to assess how well young pregnant women with chronic hypertension were investigated for secondary cause in South Auckland, compared with the recommendations of the Australasian Society for the Study of Hypertension in Pregnancy.
► Characterize the reproductive cycle of two Portuguese populations of R. decussatus ► Describe t... more ► Characterize the reproductive cycle of two Portuguese populations of R. decussatus ► Describe the patterns of nutrient stored and utilization during gametogenic cycle ► The species showed a long spawning period that is useful to aquaculture production. ► R decussatus can adopt different reproductive strategies ► Contribute to establish a successful hatchery-based production of R. decussatus
Aneuploidy is a cytogenetic phenomenon known as an abnormal diploid chromosome number. A negative... more Aneuploidy is a cytogenetic phenomenon known as an abnormal diploid chromosome number. A negative relationship between growth rate, one of the biggest problems faced by bivalve producers, and this phenomenon was already verified for two oyster species, the Japanese oyster Crassostrea gigas, the Portuguese oyster Crassostrea angulata and their interspecific hybrids and, more recently, in the carpet shell clam Ruditapes decussatus. The main objective of this study was to assess whether chromosome losses in aneuploid situations could be explained by differential chromosomal susceptibility, as previously reported in the oyster C. gigas. Thereby, we applied the restriction enzyme (RE) digestion chromosome banding technique to aneuploid karyotypes of R. decussatus and C. angulata, in order to identify the missing chromosomes. The results of this study showed that 4 out of the 19 chromosome pairs (viz. 1, 6, 12, and 19) of R. decussatus and 3 out of the 10 chromosome pairs (viz. 1, 9, and 10) of C. angulata were preferentially affected by the loss of one homologous chromosome. The chromosomal loss in C. angulata was very similar to the one previously observed in C. gigas. These results open a new field for further research in order to have a better understanding of the aneuploidy phenomenon in bivalves and particularly its negative relationship with growth rate.
We have characterized a phosphatase activity present on the external surface of intact Malpighian... more We have characterized a phosphatase activity present on the external surface of intact Malpighian tubules in Rhodnius prolixus. This phosphatase hydrolyses the substrate p-nitrophenyl phosphate at a rate of 3.38 +/- 0.07 nmol Pi x mg(-1) x min(-1). Phosphatase activity decreased with the increase of the pH from 6.4 to 7.6 pH, a range in which tubules cellular integrity was maintained for at least 1 h. Classical inhibitors of acid phosphatase, such as ammonium molybdate, fluoride, vanadate, mpV-PIC, and bpV-PHEN, caused different patters of inhibition. The ecto-phosphatase present an apparent Km of 1.67 +/- 0.34 mM and Vmax of 5.71 +/- 0.37 nmol Pi x mg(-1) x min(-1) for p-NPP. Zinc chloride inhibited 78.2% of ecto-phosphatase activity, with Ki of 0.35 mM. Such inhibition was reversed by incubation with cysteine and GSH, but not DTT, serine, and GSSG, showing that cysteine residues are important for enzymatic activity. Phosphatase activity increased 141% three days after blood meal, and returned to basal levels 2 days later. These results suggest that ecto-phosphatase activity could be involved in a diuretic mechanism, essential in the initial days after a blood meal for the control of Rhodnius homeostasis.
Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare intestinal dysmotilit... more Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare intestinal dysmotility condition that also involves a dilated urinary bladder. It was believed to be an autosomal recessive condition, but genetic studies have suggested possibly an autosomal dominant inheritance pattern. Prenatal diagnosis can be challenging, but MRI and amniotic fluid/digestive fluid studies may be complementary investigations to improve diagnostic accuracy. Prognosis of MMIHS is generally poor and treatment is mostly supportive. To date, bowel transplantation remains the only viable treatment to restore bowel motility. Here we present two additional cases to contribute towards the scant literature on this condition.
Revista Brasileira de Saúde e Produção Animal, 2012
Objetivou-se avaliar o consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA), efici... more Objetivou-se avaliar o consumo de ração (CR), ganho de peso (GP), conversão alimentar (CA), eficiência econômica e custo da inclusão do bagaço de mandioca (BM) em dietas de frangos de corte. Para tanto, foram realizados dois experimentos independentes: inicial (1 a 21 dias) e crescimento (22 a 40 dias de idade). O delineamento experimental utilizado foi em blocos casualizados (DBC) com cinco níveis (0; 5; 10; 15 e 20 %) de inclusão de bagaço de mandioca, com oito repetições e 20 aves por unidade experimental. Os resultados do primeiro experimento (1 a 21 dias de idade) mostraram efeito linear negativo da inclusão do bagaço de mandioca sobre o consumo de ração (CR = 1196.2 to 3.46BM, P <0.0008, R² = 0.832). Para o ganho de peso, houve efeito quadrático (GP = 856.506 + 2.372BM - 0,2443BM², P <0.0001, R² = 0.941), fato que o melhorou até o nível de 4,86% de bagaço de mandioca. Não foi encontrada diferença significativa para conversão alimentar. No segundo experimento (22 a 40 dia...
The commercial production of triploids, and the creation of tetraploid broodstock to support it, ... more The commercial production of triploids, and the creation of tetraploid broodstock to support it, has become an important technique in aquaculture of the eastern oyster, Crassostrea virginica. Tetraploids are produced by cytogenetic manipulation of embryos and have been shown to undergo chromosome loss (to become a mosaic) with unknown consequences for breeding. Our objective was to determine the extent of aneuploidy in triploid progeny produced from both mosaic and non-mosaic tetraploids. Six families of triploids were produced using a single diploid female and crossed with three mosaic and non-mosaic tetraploid male oysters. A second set of crosses was performed with the reciprocals. Chromosome counts of the resultant embryos were tallied at 2-4 cell stage and as 6-hour(h)-old embryos. A significant level of aneuploidy was observed in 6-h-old embryos. For crosses using tetraploid males, aneuploidy ranged from 53% to 77% of observed metaphases, compared to 36% in the diploid control. For crosses using tetraploid females, 51%-71% of metaphases were aneuploidy versus 53% in the diploid control. We conclude that somatic chromosome loss may be a regular feature of early development in triploids, and perhaps polyploid oysters in general. Other aspects of chromosome loss in polyploid oysters are also discussed.
Organometallic-cyclodextrin inclusion compounds were obtained by the treatment of molybdenocene d... more Organometallic-cyclodextrin inclusion compounds were obtained by the treatment of molybdenocene dichloride (Cp 2 MoCl 2 ) with the modified cyclodextrins (CDs) heptakis-2,3,6-tri-O-methyl-b-CD (TRIMEB) and 2-hydroxypropyl-b-CD (HPbCD) in aqueous solution. The products were isolated by liophilisation and characterised in the solid-state by powder XRD, thermogravimetric analysis, Raman and FTIR spectroscopy, and 13 C CP MAS NMR spectroscopy. The results are consistent with inclusion of Cp 2 MoCl 2 , rather than hydrolysis products such as [Cp 2 Mo(H 2 O)X] + (X = Cl, OH) or [Cp 2 Mo(H 2 O) 2 ] 2+ . The pure non-included metallocene Cp 2 MoCl 2 and its inclusion compounds with unmodified b-CD, TRIMEB and HPbCD were screened for their potential antiproliferative and cytotoxic activity, in both human cancer and healthy cell lines. Inclusion in CD was found to enhance the cytotoxic effect of Cp 2 MoCl 2 , with the TRIMEB adduct displaying the highest anti-tumour activity, along with the lowest toxicity towards non-neoplastic cells.
A microarray-based analysis was performed with the objective of describing genomic features of oo... more A microarray-based analysis was performed with the objective of describing genomic features of oocytes and looking for potential markers of oocyte quality in the economically important European clam, Ruditapes decussatus. Oocytes of 25 females from Ria de Aveiro, western coast of Portugal (40°42′N; 08°40′W) were selected for this study and oocyte quality was estimated by success of D-larval rate under controlled conditions, which appeared to vary from 0 to 95%. By genome-wide expression profiling with a DNA microarray, 526 probes appeared differentially expressed between two groups representing the largest and smallest value of D larval rates, named good (represented by a mean D-larval yield of 57 ± 22%) and poor (9 ± 5%) quality oocytes. Enrichment analysis showed "lysosome" (dre04142) as the single pathway represented in the enriched KEGG pathway terms, with 8 genes coding for putative cathepsins. Furthermore, differentially expressed genes involved in oocyte protection (DnaJ (Hsp40), Hsp70, cyclophilin B, PDI), maturation (Cam-PDE1C, PRDM9, G protein), sperm-egg interaction (PDI, G protein) and apoptosis (TNF) were also identified. From these, the apoptosis pathway was supposed to assume an important role in oocyte quality as the mRNA level of caspase 8 appeared also negatively correlated with the D-larval yield. Finally, a G-protein transcript was identified as more abundant in poor quality oocytes, which underlines the importance of release prophase I block and meiotic maturation in the oocytes of this species. This study provided new highly valuable information on genes specifically expressed by mature oocytes of R. decussatus, for further understanding of the mechanisms of early development in this species.
The production of Venerupis decussata relies on wild seed collection, which has been recently com... more The production of Venerupis decussata relies on wild seed collection, which has been recently compromised due to recruitment failure and severe mortalities. To address this issue and provide an alternative source of seed, artificial spawning and larval rearing programs were developed. However, hatchery-based seed production is a relatively new industry and it is still underdeveloped. A major hurdle in the European clam seed production is the control of spawning and reproduction, which is further hindered by the impossibility of obtaining fertile gametes by gonadal "stripping", as meiosis re-initiation is constrained to a maturation process along the genital ducts. In the present study, oocytes were collected from 15 females and microarray analyses was performed to investigate gene expression profiles characterizing released and stripped ovarian oocytes. A total of 198 differentially expressed transcripts between stripped and spawned oocytes were detected. Functional analys...
The European clam, Ruditapes decussatus is a species with a high commercial importance in Portuga... more The European clam, Ruditapes decussatus is a species with a high commercial importance in Portugal and other Southern European countries. Its production is almost exclusively based on natural recruitment, which is subject to high annual fluctuations. Increased knowledge of the natural reproductive cycle of R. decussatus and its molecular mechanisms would be particularly important in providing new highly valuable genomic information for better understanding the regulation of reproduction in this economically important aquaculture species. In this study, the transcriptomic bases of R. decussatus reproduction have been analysed using a custom oligonucleotide microarray representing 51,678 assembled contigs. Microarray analyses were performed in four gonadal maturation stages from two different Portuguese wild populations, characterized by different responses to spawning induction when used as progenitors in hatchery. A comparison between the two populations elucidated a specific pathway involved in the recognition signals and binding between the oocyte and components of the sperm plasma membrane. We suggest that this pathway can explain part of the differences in terms of spawning induction success between the two populations. In addition, sexes and reproductive stages were compared and a correlation between mRNA levels and gonadal area was investigated. The lists of differentially expressed genes revealed that sex explains most of the variance in gonadal gene expression. Additionally, genes like Foxl2, vitellogenin, condensing 2, mitotic apparatus protein p62, Cep57, sperm associated antigens 6, 16 and 17, motile sperm domain containing protein 2, sperm surface protein Sp17, sperm flagellar proteins 1 and 2 and dpy-30, were identified as being correlated with the gonad area and therefore supposedly with the number and/or the size of the gametes produced. Citation: de Sousa JT, Milan M, Bargelloni L, Pauletto M, Matias D, et al. (2014) A Microarray-Based Analysis of Gametogenesis in Two Portuguese Populations of the European Clam Ruditapes decussatus. PLoS ONE 9(3): e92202.
The cularines are isoquinoline alkaloids which contain a dihydrooxepine ring system' and occur ma... more The cularines are isoquinoline alkaloids which contain a dihydrooxepine ring system' and occur mainly in the Fumaraceae family.2a Some members are muscle relaxants.2b A number of syntheses of (+)-cularine (la)J and of the isomeric (+)-sarcocapnine2~~ have appeared. (+)-Sarcocapnidine (2b) and 0-demethyl-1 (lb) were obtained in very low yield by the KJ-Fe(CN)6 oxidation of crassifoline .2v4d.f We now report a new 1 (a:
Journal of Experimental Marine Biology and Ecology, 2011
... Joana Teixeira de Sousa a , b , Domitília Matias a , Sandra Joaquim a , Radhouan Ben-Hamadou ... more ... Joana Teixeira de Sousa a , b , Domitília Matias a , Sandra Joaquim a , Radhouan Ben-Hamadou c and Alexandra Leitão a , low asterisk ... assessment of the physiological status of the shellfish populations and is recognized as a useful biomarker (eg [Fernández-Castro and Vido ...
Australian and New Zealand Journal of Obstetrics and Gynaecology, 2009
Women with chronic hypertension are at higher risk of adverse obstetric outcomes. It is essential... more Women with chronic hypertension are at higher risk of adverse obstetric outcomes. It is essential that the condition is identified and evaluated appropriately in early pregnancy. Therefore, an audit has been carried out to assess how well young pregnant women with chronic hypertension were investigated for secondary cause in South Auckland, compared with the recommendations of the Australasian Society for the Study of Hypertension in Pregnancy.
► Characterize the reproductive cycle of two Portuguese populations of R. decussatus ► Describe t... more ► Characterize the reproductive cycle of two Portuguese populations of R. decussatus ► Describe the patterns of nutrient stored and utilization during gametogenic cycle ► The species showed a long spawning period that is useful to aquaculture production. ► R decussatus can adopt different reproductive strategies ► Contribute to establish a successful hatchery-based production of R. decussatus
Aneuploidy is a cytogenetic phenomenon known as an abnormal diploid chromosome number. A negative... more Aneuploidy is a cytogenetic phenomenon known as an abnormal diploid chromosome number. A negative relationship between growth rate, one of the biggest problems faced by bivalve producers, and this phenomenon was already verified for two oyster species, the Japanese oyster Crassostrea gigas, the Portuguese oyster Crassostrea angulata and their interspecific hybrids and, more recently, in the carpet shell clam Ruditapes decussatus. The main objective of this study was to assess whether chromosome losses in aneuploid situations could be explained by differential chromosomal susceptibility, as previously reported in the oyster C. gigas. Thereby, we applied the restriction enzyme (RE) digestion chromosome banding technique to aneuploid karyotypes of R. decussatus and C. angulata, in order to identify the missing chromosomes. The results of this study showed that 4 out of the 19 chromosome pairs (viz. 1, 6, 12, and 19) of R. decussatus and 3 out of the 10 chromosome pairs (viz. 1, 9, and 10) of C. angulata were preferentially affected by the loss of one homologous chromosome. The chromosomal loss in C. angulata was very similar to the one previously observed in C. gigas. These results open a new field for further research in order to have a better understanding of the aneuploidy phenomenon in bivalves and particularly its negative relationship with growth rate.
We have characterized a phosphatase activity present on the external surface of intact Malpighian... more We have characterized a phosphatase activity present on the external surface of intact Malpighian tubules in Rhodnius prolixus. This phosphatase hydrolyses the substrate p-nitrophenyl phosphate at a rate of 3.38 +/- 0.07 nmol Pi x mg(-1) x min(-1). Phosphatase activity decreased with the increase of the pH from 6.4 to 7.6 pH, a range in which tubules cellular integrity was maintained for at least 1 h. Classical inhibitors of acid phosphatase, such as ammonium molybdate, fluoride, vanadate, mpV-PIC, and bpV-PHEN, caused different patters of inhibition. The ecto-phosphatase present an apparent Km of 1.67 +/- 0.34 mM and Vmax of 5.71 +/- 0.37 nmol Pi x mg(-1) x min(-1) for p-NPP. Zinc chloride inhibited 78.2% of ecto-phosphatase activity, with Ki of 0.35 mM. Such inhibition was reversed by incubation with cysteine and GSH, but not DTT, serine, and GSSG, showing that cysteine residues are important for enzymatic activity. Phosphatase activity increased 141% three days after blood meal, and returned to basal levels 2 days later. These results suggest that ecto-phosphatase activity could be involved in a diuretic mechanism, essential in the initial days after a blood meal for the control of Rhodnius homeostasis.
Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare intestinal dysmotilit... more Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare intestinal dysmotility condition that also involves a dilated urinary bladder. It was believed to be an autosomal recessive condition, but genetic studies have suggested possibly an autosomal dominant inheritance pattern. Prenatal diagnosis can be challenging, but MRI and amniotic fluid/digestive fluid studies may be complementary investigations to improve diagnostic accuracy. Prognosis of MMIHS is generally poor and treatment is mostly supportive. To date, bowel transplantation remains the only viable treatment to restore bowel motility. Here we present two additional cases to contribute towards the scant literature on this condition.
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Papers by Joana De Sousa