Anti-Bacterial and Anti-Oxidant Activities of Leaf Extracts of Combretum Vendae (Combretecacea) and the Isolation of an Anti-Bacterial Compound

Background

Combretum vendae A.E. van Wyk (Combretaceae) is used for the treatment of bacterial related infections and oxidative related diseases by indigenous people of South Africa. Dried leaves extracts of C. vendae were investigated for bioactivity against a variety of bacterial strains and their antioxidant potential evaluated.

Materials and methods

Constituents of leaf material were serially extracted using solvents of varying polarities, TLC chromatograms of the fractions were sprayed with 2,2 diphenyl-1-picrylhydrazyl (DPPH) to determine the presence of antioxidant compounds. Bio-autography was used to determine the number of antibacterial compounds active against Staphylococcus aureus, Enterococcus faecalis, Eschericha coli and Pseudomonas aeruginosa. Minimum inhibitory concentration (MIC) values were determined using serial microplate dilution method. The chloroform fraction was subjected to bio-assay guided column chromatography to isolate the active compound.

Results

The mass extracted by different solvents was below 10% dry weight. MIC values for different extracts against different pathogens ranges from 0.08 to 0.64 mg/ml. The compound isolated was identified as acacetin having an R_f value of 0.28 following elution in the Ethanol: Methanol: Water [E: M: W (10: 1.35: 1 v/v). Acacetin had MIC values ranging from 0.16 to 0.35 mg/ml.

Conclusion

We report for the first time the isolation of acacetin as the main antibacterial compound from the leaves of Combretum vendae.     

Evaluation of antibacterial,antifungal and modulatory activity of methanol and ethanol extracts of Padina sanctae-crucis

Background

Multi-resistantmicroorganisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida tropicalis e Candida krusei are the main causes of microbial infections. Padina sanctae-crucis is a seaweed often used to check the contamination of ecosystems by materials such as heavy metals, but studies of the antimicrobial activity of the same seaweed were not found.

Methods

The tests for the minimum inhibitory concentration and modulation of microbial resistance, with the use of ethanolic and methanolic extracts of Padina Sanctae-cruces combined with drugs of the class of aminoglycosides and antifungal were used to evaluate the activity against the cited microorganisms.

Results

Was observed a modulation of antibiotic activity between the natural products and the E. coli and S. aureus strains, indicating a synergism and antagonism respectively.

Conclusions

The results showed a moderate modulatory effect against some microorganisms studied.     

Characterization of plasma membrane bound inorganic pyrophosphatase from Leishmania donovani promastigotes and amastigotes

Background

Currently, a major problem in the management of visceral leishmaniasis or kala-azar, especially in the Indian subcontinent, is the growing unresponsiveness to conventional antimonial therapy. Membrane bound pyrophophatase (PPases) do not exist in plasma membrane from mammals. Thus, H⁺-PPases from Leishmania plasma membrane might be potential target in rational chemotherapy of the disease caused by Leishmania parasites.

Objective

To characterize the activities of inorganic pyrophophatase (PPase) in the plasma membrane of Leishmania donovani promastigote and amastigote.

Methods

Culture method of promastigote and amastigote were developed. We assayed PPase activity in isolated plasma membrane of L. donovani.

Results

We characterized K⁺-PPase present in the plasma membrane of Leishmania donovani and investigated its possible role in the survival of promastigote and amastigote. PPase activity was stimulated by K⁺ ions and sodium orthovanadate, inhibited by pyrophosphate analogs imidodiphosphate and alendronate, KF, DCCD, thiol reagent parachloromercuribenzenesulfonate (PCMBS), N-ethylmaliemide (NEM), phenylarsineoxide, ABC superfamily transport modulator verapamil and was also by F₁F_o-ATPase inhibitor quercetin.

Conclusion

We conclude that there are significant differences within promastigote, amastigote and mammalian host in cytosolic pH homeostasis to merit the inclusion of PPase transporter as putative targets for rational drug design.     

The prevalence of aminoglycoside-modifying enzyme genes (aac (6')-I, aac (6')-II, ant (2")-I, aph (3')-VI) in Pseudomonas aeruginosa

INTRODUCTION:

Pseudomonas aeruginosa (P. aeruginosa) is one of the primary opportunistic pathogens responsible for nosocomial infections. Aminoglycosides are an important component of antipseudomonal chemotherapy. The inactivation of drugs by modifying enzymes is the most common mechanism of aminoglycoside resistance.

OBJECTIVES:

The inactivation of aminoglycosides by modifying enzymes is the primary resistance mechanism employed by P. aeruginosa. The aim of the present study was to investigate the occurrence of aminoglycoside resistance and the prevalence of four important modifying enzyme genes (aac (6′)-I, aac (6′)-II, ant (2″)-I, aph (3′)-VI) in P. aeruginosa in Iran.

METHODS:

A total of 250 clinical isolates of P. aeruginosa were collected from several hospitals in seven cities in Iran. Antimicrobial susceptibility tests (using the disk diffusion method and E-tests) were performed for all 250 isolates. In addition, all isolates were screened for the presence of modifying enzyme genes by polymerase chain reaction.

RESULTS:

The resistance rates, as determined by the disk diffusion method, were as follows: gentamicin 43%, tobramycin 38%, and amikacin 24%. Of the genes examined, aac (6′)-II (36%) was the most frequently identified gene in phenotypic resistant isolates, followed by ant (2″)-I, aph (3′)-VI, and aac (6′)-I.

CONCLUSIONS:

Aminoglycoside resistance in P. aeruginosa remains a significant problem in Iran. Therefore, there is considerable local surveillance of aminoglycoside resistance.     

In vitro evidence of possible influence of scutellarein towards bile acids' metabolism

Background

The glucuronidation process has been regarded as the key elimination process for toxic bile acids. UDP-glucuronosyltransferase (UGT) 1A3 is one important metabolizing enzyme involved in this process.

Objective

To evaluate the inhibition of UGT1A3 by scutellarein which is an important herbal ingredient using in vitro method, trying to indicate the possibility of toxicity due to the accumulation of toxic bile acids.

Methods

Due to the difficulty to gain the standards of biles acids'' glucuronides, the recombinant UGT1A3-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction was employed to profile the activity of UGT1A3.

Results

The results showed that scutellarein inhibited UGT1A3 in a concentration-dependent behaviour. Competitive inhibition was demonstrated using both Dixon plot and Lineweaver-Burk plot, and the inhibition kinetic parameter (K_i) was calculated to be 5.8uM.

Conclusion

All these data reminded the necessary monitoring of the levels of bile acids in plasma when utilizing scutellarein and the herbs containing this compound.     

Baboons as potential reservoirs of zoonotic gastrointestinal parasite infections at Yankari National Park,Nigeria

Background

Zoonoses pose a risk to public health.

Objective

To carry out the investigation of the prevalence of gastrointestinal parasites of baboons, Papio anubis, frequenting the Wikki base Camp in Yankari National Park, Nigeria

Method

Formol-ether concentration technique was used to isolate parasite eggs and cysts from faecal samples.

Results

Parasites recovered were Ascaris lumbricoides, Ancylostoma duodenale, Strongyloides stercoralis, Fasciola sp, Schistosoma mansoni, Hymenolepis nana, and Trichostrongylus sp, and cysts of protozoan parasites Entomoeba histolytica, E. coli, and Iodamoeba butschii.

Conclusion

Most of the parasites identified are known to have high pathologic involvement in humans, implicating the baboons as potential source and reservoirs for human zoonotic parasitic infections although further molecular work would be necessary to ascertain if these gastrointestinal parasites are the same strains that infect humans     

PTK2 and PTPN11 expression in myelodysplastic syndromes

OBJECTIVE:

The aim of this study was to evaluate the expression of protein tyrosine kinase 2 and protein tyrosine phosphatase non-receptor type 11, which respectively encode focal adhesion kinase protein and src homology 2 domain-containing protein-tyrosine phosphatase 2, in hematopoietic cells from patients with myelodysplastic syndromes.

METHODS:

Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions were analyzed by quantitative polymerase chain reaction in bone marrow cells from patients with myelodysplastic syndromes and healthy donors.

RESULTS:

Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions did not significantly differ between normal cells and myelodysplastic cells.

CONCLUSIONS:

Our data suggest that despite the relevance of focal adhesion kinase and src homology 2 domain-containing protein-tyrosine phosphatase 2 in hematopoietic disorders, their mRNA expression do not significantly differ between total bone marrow cells from patients with myelodysplastic syndromes and healthy donors.     

Novel nonsense mutation of BRCA2 gene in a Moroccan man with familial breast cancer

Background

Breast cancer is the most common cancer in women worldwide. About 5 to 10% of cases are due to an inherited predisposition in two major genes, BRCA1 and BRCA2, transmitted as an autosomal dominant form. Male breast cancer is rare and is mainly due to BRCA2 than BRCA1 germline mutations.

Objective

Molecular study of BRCA2 gene in man with familial breast cancer.

Methods

PCR and direct sequencing of BRCA2 gene.

Results

Identification of novel heterozygous germline mutation c.6428C>A ; p.Ser2143Stop of BRCA2 gene.     

Experimental Study on the Optimization of Extraction Process of Garlic Oil and its Antibacterial Effects

Background

Garlic oil which is the main active constituent of garlic has a wide range of pharmacological activities, and a broad antibacterial spectrum. It also has a strong anti-cancer activity, and can significantly inhibit a variety of tumors such as liver cancer, gastric cancer and colon cancer. The objective is to study the extraction process of garlic oil and its antibacterial effects.

Materials and Methods

CO₂ Supercritical extraction was used to investigate the optimal processing conditions for garlic oil extraction; filter paper test and suspension dilution test were applied to determine the bacteriostatic action of garlic oil.

Results

In the CO₂ supercritical extraction experiment, factors influencing the yield of garlic oil were: extraction pressure > extraction temperature > extraction time in descending order. Range analysis showed that the optimal experimental conditions for CO₂ supercritical extraction of garlic oil were extraction pressure of 15 Mpa, temperature of 40 °C, and duration of 1 h. Different concentrations of garlic oil could all inhibit the growth of Staphylococcus aureus, Escherichia coli and Bacillus subtilis, suggesting that garlic oil has an antibacterial effect.

Conclusion

The optimal experimental conditions for CO₂ supercritical extraction of garlic oil were: extraction pressure of 15 Mpa, temperature of 40 °C, and duration of 1 h; garlic oil has an antibacterial effect.     

Clinical review of endogenous endophthalmitis in Korea: a 14-year review of culture positive cases of two large hospitals

Purpose

To identify the clinical features and outcomes of endogenous endophthalmitis in Korea.

Materials and Methods

We reviewed 18 patients with endogenous endophthalmitis at 2 Korean hospitals, treated over a 14 year period between January 1993 and December 2006.

Results

The comorbidities observed in these cases were diabetes mellitus and liver cirrhosis. The most common pathogens, which were found in 7 patients each (38.9%), were Klebsiella pneumonia and Pseudomonas aeruginosa. All patients were treated with systemic antibiotics and fortified topical antibiotics. A surgical approach including vitrectomy was performed in 9 cases (50.0%). The prognosis was generally poor, and visual acuity improved slightly in 6 patients (33.3%).

Conclusion

In this study, diabetes mellitus and Klebsiella pneumonia showed a close relationship with endogenous endophthalmitis, respectively. Endogenous endophthalmitis is a serious risk to sight and careful attention to establishing the diagnosis and management may decrease the ocular morbidity.     

Acute toxicity effects of the methanolic extract of Fagara zanthoxyloides (Lam.) root-bark

Background

Fagara zanthoxyloides is a well known medicinal plant in Uganda. It is used extensively in malaria and other infections. However nothing is known about its toxicity.

Objective

The objective of the study was to evaluate the acute toxicity of the methanolic extract of the root-bark of F. zanthoxyloides, in mice.

Methods

Methanolic extract of the root-bark of the plant was administered orally to mice at various dose levels to determine the acute toxic effects and the median lethal dose (LD₅₀) in mice.

Results

The LD50 of the methanolic extract was found to be 5.0 g/Kg body weight within 95 % confidence limits. The mice showed signs of cerebral irritation before dying. Histopathological examinations of the viscera showed congestion and focal necrosis of the liver and renal tubules.

Conclusion

It was concluded that the extract of F. zanthoxyloides is safe, however the cerebral mechanism that lead to the death of the mice need to be investigated further.     

Evaluation of persistent antimicrobial effects of an antimicrobial formulation

Context:

Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is becoming more prevalent in healthy athletic populations. Various preventive measures have been proposed, but few researchers have evaluated the protective effects of a prophylactic application of a commercially available product.

Objective:

To compare the persistent antimicrobial properties of a commercially available antimicrobial product containing 4% chlorhexidine gluconate (Hibiclens) with those of a mild, nonmedicated soap (Dr. Bronner''s Magic Soap).

Design:

Cross-sectional study.

Setting:

Microbiology laboratory, contract research organization.

Patients or Other Participants:

Twenty healthy human volunteers.

Intervention(s):

The test and control products were randomly assigned and applied to both forearms of each participant. Each forearm was washed for 2 minutes with the test or control product, rinsed, and dried. At, 1, 2, and 4 hours after application, each forearm was exposed to MRSA for approximately 30 minutes.

Main Outcome Measure(s):

Differences in numbers of MRSA recovered from each forearm, test and control, at each postapplication time point were compared.

Results:

Fewer MRSA (P < .0001) were recovered from the forearms treated with the test product (4% chlorhexidine gluconate) than from the forearms treated with the control product (nonmedicated soap).

Conclusions:

The 4% chlorhexidine gluconate product demonstrated persistent bactericidal activity versus MRSA for up to 4 hours after application.     

Antidiabetic and haematinic effects of Parquetina nigrescens on alloxan induced type-1 diabetes and normocytic normochromic anaemia in Wistar rats

Background

The plant, Parquetina nigrescens is used in folklore medicine to treat diabetes mellitus and its complications in several parts of West Africa.

Objective

To determine the effect of Parquetina nigrescens extract on fasting blood glucose in alloxan-induced diabetic rats.

Methods

The blood glucose levels, complete blood count, erythrocyte indices and osmotic fragility, body and organ weights were evaluated.

Results

Diabetic rats treated with the extract showed significant (P<0.01) reduction of the blood glucose to levels comparable to that of the non-diabetic control and those treated with chlorpropamide (standard drug). Similarly, there was significant (P<0.01) reduction in the complete blood count in the diabetic rats.

Discussion

The anaemia, leucopenia and thrombocytopenia associated with the diabetes were corrected in the animals treated with the extract and chlorpropamide. The extract also reduced the erythrocyte osmotic fragility, body and organ weights. Parquetina nigrescens demonstrated antidiabetic property by reducing the elevated blood glucose in alloxan treated rats which is comparable to animals that received the standard drug.

Conclusion

Paraquetina nigrescens stabilized the erythrocyte membrane, decreased the body weight probably by lowering lipogenesis. However, the mechanism underlying the antidiabetic and haematinic properties of Parquetina nigrescens remains to be elucidated.     

Staphylococcus aureus carriage among GPs in the Netherlands

Background

The extent to which GPs serve as a reservoir for antibiotic-resistant Staphylococcus aureus is unknown and not well studied.

Aim

To determine the prevalence of nasal S. aureus carriage among GPs in the Netherlands, as well as the antimicrobial resistance and the genotypes of isolated S. aureus.

Design of study

Observational, point-prevalence, and cross-sectional study.

Setting

GPs attending the annual conference of the Dutch College of General Practitioners in 2006.

Method

Nasal swabs were randomly taken from 395 GPs and analysed for the presence of S. aureus. Antimicrobial susceptibility was determined by a microbroth dilution method and the genotypes by spa typing, which was associated with multilocus sequence typing.

Results

Of the GPs, 129/395 (33%; 95% confidence interval [CI] = 28 to 37%) were carriers of S. aureus. No meticillin-resistant S. aureus (MRSA) was found. Resistance was observed to penicillin (71%; 95% CI = 63 to 79%), fusidic acid (7%; 95% CI = 3 to 13%), and clarithromycin (6%; 95% CI = 3 to 12%). In 72% of the isolates, an MRSA-related genotype of S. aureus was found.

Conclusion

The low antibiotic resistance found among S. aureus of GPs suggests that GPs are not a reservoir of antibiotic-resistant S. aureus strains. The relatively high resistance to fusidic acid, which has not previously been described in the Netherlands and is mostly because of antibiotic use, suggests that patients infect GPs and not the other way round. GPs may be at risk for nasal carriage of S. aureus with an MRSA-related genotype.     

Study on the Inhibitory Effect of Total Alkaliods of Sophora Alopecuroides on Osteosarcoma Cell Growth

Background

Ku Dou Zi is the dried whole plant, roots and seeds of Sophora alopecuroides L. in the genus Sophora of family Leguminosae. The entire plant is bitter in taste, cold in nature, and has the heat clearing, detoxifying, pathogenic wind dispelling dampness, analgesic, and insecticidal effects. Modern pharmacological studies have proved that TASA has pharmacological activities of anti-cancer. The objective of this paper was to investigate the inhibitory effect of total alkaloids of Sophora alopecuroides (TASA), on osteosarcoma cell growth and its mechanism.

Materials and Methods

MTT assay and flow cytometry were used to study the inhibitory effect of TASA on human osteosarcoma cell line OS732.

Results

The results showed that the inhibition rates of different concentrations of TASA (1.5, 3, and 4.5g/kg), against human osteosarcoma cell line OS732, were: 18.4%, 27.4% and 52.8%, respectively.

Conclusion

TASA has an inhibitory effect on osteosarcoma cell growth.     

Lack of Association of the APOE ε4 Allele with the Risk of Obstructive Sleep Apnea: Meta-Analysis and Meta-Regression

Study Objectives:

Reports on the association of polymorphisms in the gene encoding apolipoprotein E (APOE)—a vital macromolecule in cholesterol metabolism—with obstructive sleep apnea (OSA) have provided conflicting results. Our objective was to meta-analytically synthesize the existing evidence for the association of the APOE ε4 allele with the risk of OSA.

Design:

Random effects meta-analysis and meta-regression

Setting:

Genetic epidemiological studies reporting the association of APOE ε4 allele with OSA susceptibility.

Patients or Participants:

Synthesis of APOE ε4 allele data from 6,508 subjects including 1,901 cases of OSA and 4,607 controls.

Interventions:

None

Measurements and Results:

Eight studies were included in the random effects meta-analysis; the summary effect size measured as odds ratio (OR) for association of the APOE ε4 allele with the risk of OSA was found to be 1.13 (95% confidence interval 0.86–1.47). There was a statistically significant heterogeneity (I² = 72%, P = 0.001) across study results that was not explained by the mean age, proportion of males, or the proportion possessing the APOE ε4 allele or when grouped based on the geographic location of the study.

Conclusions:

The hypothesis that the APOE ε4 allele may be causally associated with OSA cannot be supported on the basis of published literature.

Citation:

Thakre TP; Mamtani MR; Kulkarni H. Lack of association of the APOE ε4 allele with the risk of obstructive sleep apnea: meta-analysis and meta-regression. SLEEP 2009;32(11):1507-1511.     

Status of allele frequency and diversity of Plasmodium falciparum msp1, msp2 and glurp before implementation of an artemisinin-based combined therapy in Northwestern Colombia.

Introduction:

The status of msp1, msp2 and glurp allele frequency and the diversity of Plasmodium falciparum in Northwestern Colombia before the implementation of an artemisinin-combined therapy have been explored only by a few authors and in a relatively small number of samples from this highly endemic region.

Objective:

To evaluate the frequency of msp1, msp2, and glurp alleles and the diversity of P. falciparum in two Colombian regions before the use of an artemisinin-combined therapy.

Methods:

This study was part of a major anti-malarial efficacy trial designed as a random, clinically-controlled study for which 224 subjects were recruited. Region 2 of msp1 and msp2 (central region) were amplified by a nested PCR; glurp (region R2) was amplified by a semi-nested PCR.

Results:

For msp1, five genotypes were observed, representing the K1, MAD20, and RO33 allelic families. All samples corresponded to a MAD20 150 bp allele. For msp2 (IC family), two alleles were detected and for glurp, eight were observed. A total 33 haplotypes were detected.

Conclusions:

Analysis of glurpcan be used to successfully genotype parasite populations in the new studies in Colombia aimed at exploring Plasmodium spp population dynamics. In addition, analysis of msp1 and msp2 can also be of value for comparisons with past studies, but not when the objective is to study parasites obtained from the same patient in a reduced period of time; for instance, during treatment efficacy studies.     

Antimicrobial Activity of Methanolic Extracts of Sambucus Ebulus and Urtica Dioica Against Clinical Isolates of Methicillin Resistant Staphylococcus Aureus

Background

Increase in the emergence of drug -resistant pathogens led to the development of natural antimicrobials. In this study the antimicrobial effect of methanolic extracts of Sambucus ebulus and Urtica dioica on 16 skin and wound infections isolates of methicillin resistant S. aureus have been studied.

Material and Methods

Solvent extraction procedure was done using soxhlet apparatus for extracting antimicrobial agents from freeze dried plants. Antibacterial activity was measured using agar well diffusion method.

Results

The MIC of Sambucus ebulus and Urtica dioica extracts against the standard strain of S. aureus ATCC 6538 were determined using the micro dilution method at 15 mg and 20 mg respectively. All the test bacteria were found sensitive to the Sambucus ebulus extract and only one isolate was resistant to Urtica dioica extract.

Conclusion

Extracts of Sambucus ebulus and Urtica dioica possess antibacterial potency against MRSA isolates and may be used as a natural antiseptics and antimicrobial agents in medicine.     

The Antibacterial Activity of Traditionally Used Salvadora Persica L. (Miswak) and Commiphora Gileadensis (Palsam) in Saudi Arabia

Background

Nowadays there is a need to find naturally occurring substances from plants with antimicrobial activity as an alternative to available used antibiotics.

Materials and Methods

Salvadora persica (miswak) and Commiphora gileadensis were collected, dried and extracted with either methanol or warm water and the obtained extracts were assessed for their antibacterial activity against 5 different genera of bacteria using agar well diffusion method. The tested bacteria included some human pathogens.

Results

The obtained extracts exhibited considerable inhibitory effects against all the tested bacteria with various degrees of growth inhibition. It was shown that methanol extract was more effective compared to water extracts. The minimum inhibitory concentrations (MIC) of the methanol extracts ranged from 50–100 °g/ml. No toxicity was found using Artimia salina as test organism and no antitumor activity against Ehrlich ascites carcinoma.

Conclusion

S. persica and C. gileadensis showed moderate to high inhibitory activity on pathogenic bacteria with no toxicity and can be used traditionally as alternative medicine     

Cytoprotective and Antioxidant Effects of the Methanol Extract of Eremomastax Speciosa in Rats

Background

Ethno-botanical information shows that Eremomastax speciosa is used in the traditional management of various stomach complaints including gastro-duodenal ulcers.

Materials and Methods

In this study, we tested the cytoprotective potential of the whole plant methanol extract (100–200 mg/kg, p.o), against HCl/ethanol, absolute ethanol, cold/restraint stress rats, and pylorus legated rats pre-treated with indomethacin. The effects of the extract on gastric lesion inhibition, the volume of gastric juice, gastric pH, gastric acid output, mucus production and gastric peptic activity were recorded. Oxidative stress parameters were measured in blood and gastric tissue samples obtained from the animals in all the models tested.

Results

The extract significantly (p<0.05), reduced the formation of cold/restraint ulcers by (31–60%, inhibition), completely inhibited (100%) the formation of lesions induced by HCl/ethanol at the highest dose, but was less effective against absolute ethanol (22–46% inhibition). The extract (200 mg/kg), significantly reduced lesion formation (P<0.01), gastric acidity (P<0.01), and volume of gastric secretions (P<0.05), in the indomethacin/pylorus ligation model, and did not affect the activity of pepsin in gastric juice. Blood concentrations of antioxidant enzymes (catalase, SOD and GSH), increased significantly and MDA concentrations decreased in all models tested.

Conclusion

Cytoprotection by E. speciosa methanol extract was attributed to its ability to reduce acid secretion, and to enhance mucosal defence and in vivo antioxidant status.