Objective:To investigate the potential role of fresh Carica papaya(C.papaya)leaf extract on haematological and biochemical parameters and toxicological changes in a murine model.Methods:In total 36 mice were used for ...Objective:To investigate the potential role of fresh Carica papaya(C.papaya)leaf extract on haematological and biochemical parameters and toxicological changes in a murine model.Methods:In total 36 mice were used for the trial.Fresh C.papaya leaf extract[0.2 mL(2 g)/mouse]was given only to the test group(18 mice).General behavior,clinical signs and feeding patterns were recorded.Blood and tissue samples were collected at intervals.Haematological parameters including platelet,red blood cell(RBC),white blood cell<(WBC),packed cell volume(PCV),serum biochemistry including serum creatinine,serum glutamic-oxaloacetic transaminase(SCOT)and serum glutamic-pyruvic transaminase(SGPT)were determined.Organs for possible histopathological changes were examined.Results:Neither group exhibited alteration of behavior or reduction in food and water intake.Similarly,no significant changes in SCOT,SGPT and serum creatinine levels were delected in the test group.Histopathological organ changes were not observed in either group of mice except in three liver samples of the test group which had a mild focal necrosis.The platelet count(11.33±0.35)×10~5VμL(P=0.00004)and the RBC count(7.97±0.61)×10~/μL(P=0.00003)were significandy increased in the test group compared to that of the controls.However,WBC count and PCV(%)values were not changed significantly in the test group.The platelet count in the test group started to increase significantly from Day 3(3.4±0.18×10~5/μL),reaching almost a fourfold higher at Day 21(11.3×10~5/μL),while it was 3.8X10^5/μL and 5.5×10~5/μL at Day 3 and Day 21 respectively in the control.Likewise,the RBC count in the test group increased from 6×10~6/μL to 9×10~6/μL at Day 21 while it remained near constant in the control group(6×10~6μL).Conclusions:Fresh C.papaya leaf extract significandy increased the platelet and RBC counts in the test group as compared to controls.Therefore,it is very important to identify those chemicals of C.papaya leaves as it can be recommended to be used as a medication to boost thrombopoiesis and erythropoiesis in humans and in animals in which these cell lineages have been compromised.展开更多
Objective: To determine exon/intron organization of the Toxocara canis(T. canis) AK(TCAK) and to test green and black tea and several other chemicals against the activity of recombinant TCAK in the guanidino-specific ...Objective: To determine exon/intron organization of the Toxocara canis(T. canis) AK(TCAK) and to test green and black tea and several other chemicals against the activity of recombinant TCAK in the guanidino-specific region by site-directed mutants. Methods: Amplification of genomic DNA fragments containing introns was carried out by PCRs. The open-reading frame(1 200 bp) of TCAK(wild type) was cloned into the BamH 1/SalI site of pM AL-c2X. The maltose-binding protein-TCAK fusion protein was expressed in Escherichia coli TB1 cells. The purity of the expressed enzyme was verified by SDS-PAGE. Mutations were introduced into the guanidino-specific region and other areas of pM AL/TCAK by PCR. Enzyme activity was measured with an NADH-linked assay at 25℃ for the forward reaction(phosphagen synthesis). Results: Arginine kinase in T. canis has a seven-exon/six-intron gene structure. The lengths of the introns ranged from 542 bp to 2 500 bp. All introns begin with gt and end with ag. Furthermore, we measured the enzyme activity of site-directed mutants of the recombinant TCAK. The K_m value of the mutant(Alanine to Serine) decreased indicating a higher affinity for substrate arginine than the wild-type. The K_m value of the mutant(Serine to Glycine) increased to 0.19 mM. The Km value(0.19 mM) of the double mutant(Alanine-Serine to Serine-Glycine) was slightly greater than in the wild-type(0.12 mM). In addition, several other chemicals were tested; including plant extract Azadiracta indica(A. indica), an aminoglycoside antibiotic(aminosidine), a citrus flavonoid glycoside(rutin) and a commercially available catechin mixture against TCAK. Green and black tea(1:10 dilution) produced 15% and 25% inhibition of TCAK, respectively. The extract of A. indica produced 5% inhibition of TCAK. Moreover, green and black tea produced a non-competitive type of inhibition and A. indica produced a mixed-type of inhibition on TCAK. Conclusions: Arginine kinase in T. canis has a seven-exon/six-intron gene structure. However, further studies are needed to identify a specific compound within the extract causing the inhibitory effect and also to determine the molecular mechanisms behind inhibition of arginine kinase in T. canis.展开更多
Objective:To identify worms obtained from patients with eye lesions and to describe the demographic factors of patients with ocular dirofilariasis.Methods:A retrospective descriptive study was conducted in 31 worm sam...Objective:To identify worms obtained from patients with eye lesions and to describe the demographic factors of patients with ocular dirofilariasis.Methods:A retrospective descriptive study was conducted in 31 worm samples from 30 patients referred by consultant ophthalmologists between 2006 and February 2014.Data on age,sex and site of the lesion were ascertained from the details given in the referral letters.Morphological identification of the worm was based on the maximum width,length and appearance of the cuticle.The sex of the worm was determined by the width,length and presence or absence of vulva opening.PCR was performed using Dirofilaria repens specific primers to confirm the species of worms which could not be identified morphologically.Results:Most of the patients belonged to the age group of 40-49 years(mean age = 42 years).Majority of them were females(70%).Subconjunctival lesions were the most frequent presentation,while the rest(n = 4) were found on eyelids.Female worms were extracted from 18 cases,and 11 had male worms.One individual had both male and female worms in a single nodule.Adults were the most commonly affected.This pattern was different from the previous studies in Sri Lanka where the most common age group affected was younger than 9 years old.Conclusions:The present study showed a considerably high incidence of ocular dirofilariasis,stressing the importance of implementing preventive measures to reduce the transmission of this zoonotic filarial disease.展开更多
基金Supported by the National Research Council of Sri Lanka(Research Grant No.09-05)
文摘Objective:To investigate the potential role of fresh Carica papaya(C.papaya)leaf extract on haematological and biochemical parameters and toxicological changes in a murine model.Methods:In total 36 mice were used for the trial.Fresh C.papaya leaf extract[0.2 mL(2 g)/mouse]was given only to the test group(18 mice).General behavior,clinical signs and feeding patterns were recorded.Blood and tissue samples were collected at intervals.Haematological parameters including platelet,red blood cell(RBC),white blood cell<(WBC),packed cell volume(PCV),serum biochemistry including serum creatinine,serum glutamic-oxaloacetic transaminase(SCOT)and serum glutamic-pyruvic transaminase(SGPT)were determined.Organs for possible histopathological changes were examined.Results:Neither group exhibited alteration of behavior or reduction in food and water intake.Similarly,no significant changes in SCOT,SGPT and serum creatinine levels were delected in the test group.Histopathological organ changes were not observed in either group of mice except in three liver samples of the test group which had a mild focal necrosis.The platelet count(11.33±0.35)×10~5VμL(P=0.00004)and the RBC count(7.97±0.61)×10~/μL(P=0.00003)were significandy increased in the test group compared to that of the controls.However,WBC count and PCV(%)values were not changed significantly in the test group.The platelet count in the test group started to increase significantly from Day 3(3.4±0.18×10~5/μL),reaching almost a fourfold higher at Day 21(11.3×10~5/μL),while it was 3.8X10^5/μL and 5.5×10~5/μL at Day 3 and Day 21 respectively in the control.Likewise,the RBC count in the test group increased from 6×10~6/μL to 9×10~6/μL at Day 21 while it remained near constant in the control group(6×10~6μL).Conclusions:Fresh C.papaya leaf extract significandy increased the platelet and RBC counts in the test group as compared to controls.Therefore,it is very important to identify those chemicals of C.papaya leaves as it can be recommended to be used as a medication to boost thrombopoiesis and erythropoiesis in humans and in animals in which these cell lineages have been compromised.
文摘Objective: To determine exon/intron organization of the Toxocara canis(T. canis) AK(TCAK) and to test green and black tea and several other chemicals against the activity of recombinant TCAK in the guanidino-specific region by site-directed mutants. Methods: Amplification of genomic DNA fragments containing introns was carried out by PCRs. The open-reading frame(1 200 bp) of TCAK(wild type) was cloned into the BamH 1/SalI site of pM AL-c2X. The maltose-binding protein-TCAK fusion protein was expressed in Escherichia coli TB1 cells. The purity of the expressed enzyme was verified by SDS-PAGE. Mutations were introduced into the guanidino-specific region and other areas of pM AL/TCAK by PCR. Enzyme activity was measured with an NADH-linked assay at 25℃ for the forward reaction(phosphagen synthesis). Results: Arginine kinase in T. canis has a seven-exon/six-intron gene structure. The lengths of the introns ranged from 542 bp to 2 500 bp. All introns begin with gt and end with ag. Furthermore, we measured the enzyme activity of site-directed mutants of the recombinant TCAK. The K_m value of the mutant(Alanine to Serine) decreased indicating a higher affinity for substrate arginine than the wild-type. The K_m value of the mutant(Serine to Glycine) increased to 0.19 mM. The Km value(0.19 mM) of the double mutant(Alanine-Serine to Serine-Glycine) was slightly greater than in the wild-type(0.12 mM). In addition, several other chemicals were tested; including plant extract Azadiracta indica(A. indica), an aminoglycoside antibiotic(aminosidine), a citrus flavonoid glycoside(rutin) and a commercially available catechin mixture against TCAK. Green and black tea(1:10 dilution) produced 15% and 25% inhibition of TCAK, respectively. The extract of A. indica produced 5% inhibition of TCAK. Moreover, green and black tea produced a non-competitive type of inhibition and A. indica produced a mixed-type of inhibition on TCAK. Conclusions: Arginine kinase in T. canis has a seven-exon/six-intron gene structure. However, further studies are needed to identify a specific compound within the extract causing the inhibitory effect and also to determine the molecular mechanisms behind inhibition of arginine kinase in T. canis.
基金supported by the National Research Council Grant 07-38
文摘Objective:To identify worms obtained from patients with eye lesions and to describe the demographic factors of patients with ocular dirofilariasis.Methods:A retrospective descriptive study was conducted in 31 worm samples from 30 patients referred by consultant ophthalmologists between 2006 and February 2014.Data on age,sex and site of the lesion were ascertained from the details given in the referral letters.Morphological identification of the worm was based on the maximum width,length and appearance of the cuticle.The sex of the worm was determined by the width,length and presence or absence of vulva opening.PCR was performed using Dirofilaria repens specific primers to confirm the species of worms which could not be identified morphologically.Results:Most of the patients belonged to the age group of 40-49 years(mean age = 42 years).Majority of them were females(70%).Subconjunctival lesions were the most frequent presentation,while the rest(n = 4) were found on eyelids.Female worms were extracted from 18 cases,and 11 had male worms.One individual had both male and female worms in a single nodule.Adults were the most commonly affected.This pattern was different from the previous studies in Sri Lanka where the most common age group affected was younger than 9 years old.Conclusions:The present study showed a considerably high incidence of ocular dirofilariasis,stressing the importance of implementing preventive measures to reduce the transmission of this zoonotic filarial disease.