The Acetone Extract of Sclerocarya birrea

Interesting antimicrobial data from the stem bark of Sclerocarya birrea, which support its use in traditional medicine for the treatment of many diseases, have been delineated. The current study was aimed to further study some pharmacological and toxicological properties of the plant to scientifically justify its use. Anticancer activity of water and acetone extracts of S. birrea was evaluated on three different cell lines, HT-29, HeLa, and MCF-7 using the cell titre blue viability assay in 96-well plates. Apoptosis was evaluated using the acridine orange and propidium iodide staining method, while morphological structure of treated cells was examined using SEM. The acetone extract exhibited remarkable antiproliferative activities on MCF-7 cell lines at dose- and time-dependent manners (24 h and 48 h of incubation). The extract also exerted apoptotic programmed cell death in MCF-7 cells with significant effect on the DNA. Morphological examination also displayed apoptotic characteristics in the treated cells, including clumping, condensation, and culminating to budding of the cells to produce membrane-bound fragmentation, as well as formation of apoptotic bodies. The acetone extract of S. birrea possesses antiproliferative and apoptotic potential against MCF-7-treated cells and could be further exploited as a potential lead in anticancer therapy

Antibiogram of Klebsiella Pneumoniae Isolates from Buea, Cameroon.

A CAJM article on Antibiogram of Klebsiella pneumoniae pathogen in Buea, Cameroon.Klebsiella pneumoniae is an important human pathogen that has been associated in recent decades with nosocomial outbreaks.They are important opportunistic pathogens, commonly isolated from urinary tract infections, surgical wounds, nosocomial pneumonia and bloodstream infections. These organisms are also an important source of transferable antibiotic resistance, and several outbreaks caused by multiple resistant K. pneumoniae, especially the extended-spectrum B-lactamase-producing(ESBL) strains of the types TEM and SHV have been reported

Limitation in detecting African cassava mosaic geminivirus in the lignified tissues of cassava stems

Field-infected cassava stems whose leaves were identified with differential symptoms of African cassava mosaic geminivirus (ACMV) disease were assessed for index of severity of symptoms (ISS) todetermine their infection status by scoring young resultant plants in the laboratory. Extracts of young stem tissues and leaves of emergent shoots from topped stems were also assayed for occurrence ofACMV by the enzyme-linked immunosorbent assay (ELISA). Geminivirus disease incidence and severity of symptoms were most abundant on leaves of plants from cuttings of field-symptomatic (I) stems of the moderately-resistant TMS 4(2)1425 (63.2%) and the susceptible TMS 60506 (51.1%) genotypes while those from apparently symptom-free (H) stems of the resistant genotype TMS 30001 recorded significantly the least disease (0%). Similarly, the index of severity of symptoms on all plants (ISSAP) and diseased plants only (ISSDP) were significantly highest on leaves of TMS 4(2)1425 (2.42 and 2.83), and were significantly the least (1) on leaves of TMS 30001, respectively. ACMV was not detected inextracts of all sections of lignified cassava stems by ELISA as all absorbance values were below threshold (0.0890). However, the virus was detected at greater concentrations in leaves of emergentaxillary shoots regenerating on topped plants of all node types of TMS 60506 and TMS 4(2)1425 as well as the base (node 1) of TMS 30001 stems but not on those from middle and uppermost nodes (10 and20, respectively) of the latter genotype. The highest absorbance values were recorded on shoots on node 1 of TMS 60506 (0.1720 ± 0.096), TMS 4(2)1425 (0.1640 ± 0.115) and TMS 30001 (0.1580 ± 0.080) inthat order, while the least values were on nodes 10 (0.0298 ± 0.020) and 20 (0.0289 ± 0.019) of TMS 30001

Phenotypic Characterization of Salmonella Typhimurium Isolates from Food-animals and Abattoir Drains in Buea, Cameroon

Salmonella spp. have been extensively incriminated worldwide as common causes of bacterial gastroenteritis in humans, with food-animals serving as important reservoirs. The study was aimed at investigating cattle and pigs slaughtered in Buea as reservoirs of Salmonella Typhimurium and the susceptibility of isolates to antibiotics. In total, 230 specimens (comprising 50 each from the rectum, ileum, and gall bladder of cattle; and 10 each from same anatomical sites of pigs and 50 from abattoir drains) were analyzed for Salmonella using the standard microbiological, biochemical and serological techniques. Antibiotic susceptibility of the isolates was determined by the Kirby-Bauer disc-diffusion test. The isolates were characterized into biotypes using the API 20E kit, and results were analyzed using the chi-square test. Seventy-five (32.6%) of the 230 specimens were positive for S. Typhimurium, with pigs and abattoir drains presenting the highest level of isolation (40%). Biochemical typing grouped the isolates into five biotypes. Biotype I was the most prevalent (30.6%) while biotype IV was the least prevalent (9.3%) and was absent in samples from pigs. Antibio-tic susceptibility studies revealed 14 antibiotypes based on antibiotics used in the study. The predominant antibiotype AMXR DOXRCEFR was recorded in 13 (17.3%) of the isolates. Multidrug resistance (to four or more antibiotics) was recorded in 50.7% (38/75) of the isolates. The most active drugs were ciprofloxacin (98.6%), ofloxacin (93.3%), amikacin (90.6%), and gentamicin (84%). All the isolates (100%) were resistant to tetracycline and ampicillin. Cattle and pigs were found to be reservoirs of S. Typhimurium in the environment of Buea, Cameroon, implying that foods from these sources, if not properly handled, could serve as vehicles for its transmission to humans

Isolation and molecular characterization of Bacillus cereus from cow’s raw milk

Bacillus cereus is a group of ubiquitous facultative anaerobic spore forming Gram-positive rods commonly found in soil. It has been detected and implicated in several contaminated food products and raw milk in dairy farms and it causes foodborne gastroenteritis by producing several toxins. This study is aimed at characterizing virulence determinants of B. cereus from cow‟s raw milk. A total of 400 raw milk samples were collected in Fort Hare Dairy Trust and Middledrift Dairy Farm; and cultured on Polymyxin pyruvate Egg-Yolk Mannitol Bromothymol Agar (PEMBA) for 48 hours at 37°C. DNA was isolated from the isolates and 16S rDNA was amplified and sent to Central Analytical Laboratory for sequencing. The gyrB gene of B. cereus was also used to confirm the identity of the isolates. Antibiotic susceptibility profiles of the isolates together with virulence genes were investigated. Multilocus Sequence typing was used to investigate the genetic relatedness of some selected isolates. Furthermore, spores of the isolates were produced, harvested and their concentrations determined. All (100%) of the isolates were identified as having a 96-99% similarity to B. cereus, B. thuringiensis and B. anthracis using sequencing; while gyrB gene was observed in all (100%) of the isolates. Three virulence genes nheA, nheB, nheC encoding for non haemolysin enterotoxin were amplified in all (100%) the isolates. All (100%) of the isolates were susceptible to doxycycline, gentamycin, tetracycline, ciprofloxacin, chloramphenicol and streptomycin. Resistance to rifampicin and penicillin G was predominant with equal rate of 100%, while susceptibility to erythromycin, clindamycin and doxycycline ranged from 60% to 100%. The selected isolates were related and are descendants of the same ancestor. All (100%) the isolates produced spores. The B. cereus isolates contain virulence genes, has multiple antibiotic drug resistance and produce spores, which poses a health risk to the public and cannot be used as probiotics

Evaluation of the Acetone and Aqueous Extracts of Mature Stem Bark of Sclerocarya birrea for Antioxidant and Antimicrobial Properties

We assayed the antimicrobial activity of acetone and aqueous extracts of the stem bark of Sclerocarya birrea on some selected bacteria and fungi species including; Streptococcus pyogenes, Plesiomonas shigelloides, Aeromonas hydrophila, Salmonella typhimurium, Cryptococcus neoformans, Candida glabrata, Trichosporon mucoides, and Candida krusei using both agar well diffusion and minimum inhibitory concentration (MIC) assays. Based on the levels of activity, the acetone extract was examined for total polyphenolic content, radical scavenging and antioxidant activities. Total phenols of the extract were determined spectrophotometrically. The antioxidant activity was determined by the DPPH, ABTS and reducing power. All the bacteria and fungi species were susceptible to the plant extracts. The acetone extract was the most active for the bacterial species with MIC (0.156–0.625 mg/mL) while the aqueous extract was the most active for the fungi species with MIC (0.3125–1.25 mg/mL). The polyphenolic compounds were found as 27.2 mg/g tannic acid equivalent, 25.2 mg/g quercetin equivalent, 9.1 mg/g quercetin equivalent for phenols, flavonoid and flavonols respectively. The acetone extract exhibited a remarkable ability to scavenge radicals, strong reducing ability and a potential source of natural antioxidants. Both the acetone and aqueous extracts of S. birrea may provide a target for drug discovery

Increasing trend of metronidazole resistance in the treatment of Helicobacter pylori infection: A global challenge

Helicobacter pylori are gram negative spiral bacteria that colonize the human stomach. Infection with H. pylori is associated with chronic gastritis, peptic ulcer, gastric adenocarcinoma and gastric mucosaassociatedlymphoid tissue (MALT) lymphoma. Antibiotic resistance is an ever increasing problem with the treatment of most microbial infections including H. pylori; and has become a growing problem worldwide with the eradication of this organism. In recent years, several treatment regimens have been proposed for H. pylori eradication. However, the only conditions for which such treatment is strongly recommended on the basis of unequivocal supporting evidence are peptic ulcer disease and low gradegastric MALT lymphoma. Success of antimicrobial regimens for H. pylori eradication depends on patient compliance and lack of antimicrobial resistance. Metronidazole (Mtz) containing regimens have been shown to limit effectiveness because of increasing prevalence of resistance to this drug. A high prevalence (> 90%) of Mtz resistance in H. pylori has been reported especially in developing countries. Mtz resistance may be mediated through an inability of Mtz-resistant strains to remove oxygen from the site of Mtz reduction, thereby preventing Mtz activation. This has been attributed to a mutation on the frxA and/or rdxA genes resulting in strains of the organism with defective nitro-reductases coded bythese genes. Infection by Mtz or amoxicillin resistant strains is an important factor leading to treatment failure; subjecting all H. pylori clinical isolates to susceptibility testing most especially to Mtz is recommended. If not possible, a program to survey the prevalence of resistance should beimplemented in a given area or population. This increasing emergence of antimicrobial resistance in H.pylori treatment posses serious public health problems and is therefore necessary that new drug regimens be examined

Risk factors for wound infection in health care facilities in Buea, Cameroon: aerobic bacterial pathogens and antibiogram of isolates

Introduction: Wound infection is a significant clinical challenge in hospitals in developing countries  where proper healthcare delivery is hampered by limited resources. This study investigated the antibiotic susceptibility pattern of bacteria causing wound infection and risk factors for infection among hospitalized patients in Buea, Cameroon, to generate findings which could drive reformation of policies on infection control.Methods: Aerobic bacteria were isolated from 212 swabs collected from patients with clinically  diagnosed infected wounds. Risk factors for wound infection were investigated. Antibiotic susceptibility of isolates was determined by disk diffusion technique. The Chi-square test was employed to determine significant differences in isolation and distribution of organisms in various specimens. Differences were considered significant at P < 0.05.Results: Twelve bacteria species were isolated from 169 (79.7%) specimens. Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae, the predominant isolates in all wound types  exhibited a high preponderance of multidrug resistant strains. High rate of infection was attributed tolack of constant water supply and breakdown of sterilization equipment during the study period. Highest diversity of pathogens occurred in open wounds. There were no significant differences (P>0.05) in isolation of pathogens with respect to age, gender and wound type. Co-existing morbidity increased risk of wound infection. Isolates were susceptible to fluoroquinolones and resistant to oxacillin. Conclusion: Wound infection with resistant bacteria constitutes a significant cause of morbidity in the study area. Findings reiterate the need to strengthen infection control and drug dispensing policies, and greater  collaboration between microbiologists and medical practioners to stem the spread of resistant bacteria.Key words: Wound infection; antibiotic susceptibility; co-morbidity, bacterial pathogens, Cameroo

Helicobacter pylori prevalence in dyspeptic patients in the Eastern Cape province – race and disease status

Objectives. We examined Helicobacter pylori infection in patients with gastric-related morbidities at Livingstone Hospital, Port Elizabeth, to determine the prevalence and risk factors for infection according to race, endoscopic diagnosis, age and sex. Methods. Gastric biopsies were collected from 254 consecutive patients and H. pylori was isolated on Columbia agar base supplemented with 7% sheep’s blood and Skirrow’s supplement containing trimethoprim (2.5 mg), vancomycin (5 mg) and cefsulodin (2.5 mg). Amphotericin (2.5 mg) was added to the medium. Recovered isolates were identified following standard microbiology and biochemical techniques. Presumptive isolates were further confirmed by polymerase chain reaction (PCR) targeting the glmM gene. Fisher’s exact test was used to assess the univariate association between H. pylori infection and the possible risk factors. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to measure the strength of association, using EPI INFO 3.41 software. p-value