Effect of Cissampelos capensis rhizome extract on human spermatozoa in vitro.

Cissampelos capensis is commonly known by the Afrikaans name 'dawidjies' or 'dawidjieswortel'. C. capensis is the most important and best-known medicinal plant of the family Menispermaceae used by the Khoisan and other rural people in the western regions of South Africa. Among numerous other ailments, it is traditionally taken to treat male fertility problems. Yet, no studies have investigated the effects of this plant or its extracts on human spermatozoa. The aim of study was to investigate the effects of C. capensis extracts on sperm function. A total of 77 semen samples were collected. Spermatozoa were washed with HTF-BSA medium and incubated with different concentrations of C. capensis (0, 0.05, 0.5, 5, 50, 200 µg ml(-1) ) for 1 h at 37 °C. Sperm motility, vitality, acrosome reaction, reactive oxygen species (ROS), capacitation, Annexin V binding, DNA fragmentation and mitochondrial membrane potential (Δψm ) were determined. While viability, Annexin V positivity and Δψm were not affected, the percentages of ROS-positive, TUNEL-positive, capacitated and hyperactivated spermatozoa increased significantly and dose-dependently. It is concluded that the alkaloids present in the extract of C. capansis rhizomes triggered sperm intrinsic superoxide production leading to sperm capacitation and DNA fragmentation.

Typha capensis (Rohrb.)N.E.Br. (bulrush) extract scavenges free radicals, inhibits collagenase activity and affects human sperm motility and mitochondrial membrane potential in vitro: a pilot study.

The biodiversity in South Africa provides more than 30,000 higher plants, of which more than 3000 are used by traditional healers to treat diseases. Typha capensis (bulrush) is one of the medicinal plants used in South Africa to treat male fertility problems. Considering that South African traditional healers have been recognised by Law and the health benefits of T. capensis have not been scientifically investigated yet, this study aimed at investigating the in vitro effects of aqueous extracts from this plant on male reproductive functions. Both leaves and rhizomes of T. capensis were dried, infused with distilled water and freeze-dried. Motile sperm from 50 men were isolated by swim-up and incubated with 1 µg ml(-1) aqueous extract of Typha rhizome for 1 h at 37 °C. Vitality, motility, sperm production of reactive oxygen species and mitochondrial membrane potential were analysed in the test sample, a control and in the pellet from the swim-up. Results showed that the rhizome extract had significant (P < 0.0001) negative effects on all parameters. The extracts from the leaves and rhizomes revealed dose-dependent inhibitory activity for collagenase and free radical formation. No inhibitory activity for elastase was found. The inhibitory activity for collagenase might indicate possible anti-cancer effects.

Medicinal plant use in the Bredasdorp/Elim region of the Southern Overberg in the Western Cape Province of South Africa.

There are many individuals in the Bredasdorp/Elim area who still use plants as medicines to treat many conditions. This study aimed to document some of this knowledge and present an inventory of all the plants in use in the area. Over 40 individuals were interviewed from old age homes, community centres for the elderly as well as people who were known for their knowledge in this matter. The information was gathered by means of questionnaires. In total, 36 plant species from 19 families were found to be in general use in the area. Only 58% of these plants are indigenous to South Africa, 33% are introduced species and 9% are naturalized species. The dominant families were Asteraceae, Lamiaceae, Alliaceae and the Solanaceae. Many of the plants in use are commonly used in traditional medicine around South Africa and share many of the same uses. Some uses, which have not been seen in the consulted literature, have also been documented. A more structured questionnaire was used to determine which plants were most popular for particular ailments. It was found that Artemisia afra and Ruta graveolens were the most popular.

An assessment of two Carpobrotus species extracts as potential antimicrobial agents.

For centuries, indigenous people in South Africa have used a variety of medicinal herbs to treat chronic infections. This investigation focused on two Carpobrotus species belonging to the family, Aizoaceae, in an attempt to assess their antimicrobial potential. Extracts of varying polarities of the plants were prepared and tested against Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Mycobacterium smegmatis. For the disc diffusion method, Ciprofloxacin (40 microg/disc) served as positive control for S. aureus, P. aeruginosa and M. smegmatis, whereas amphotericin B (25 microg/disc) was the control for C. albicans. A sample concentration of 10 mg/ml was used. Minimum inhibitory concentrations (MIC) were determined by two-fold serial dilution. Phytochemical analysis was completed to test for the presence of flavonoids, hydrolysable tannins, phytosterols and aromatic acids. The ethyl acetate extracts (21 microl of 95 mg/ml) were used for bio-autography, together with TLC analyses. Carpobrotus muirii and Carpobrotus quadrifidus showed antimicrobial activity against S. aureus and M. smegmatis in the disc diffusion method and inhibition against S. aureus and M. smegmatis was observed by clear zones on the TLC plate. This investigation confirms that extracts of these Carpobrotus species that are used as indigenous medicines, exhibit anti-bacterial activity. This scientific information can serve as an important platform for the development of inexpensive, safe and effective natural anti-infective medicines.

Rapid and recent origin of species richness in the Cape flora of South Africa.

The Cape flora of South Africa grows in a continental area with many diverse and endemic species. We need to understand the evolutionary origins and ages of such 'hotspots' to conserve them effectively. In volcanic islands the timing of diversification can be precisely measured with potassium-argon dating. In contrast, the history of these continental species is based upon an incomplete fossil record and relatively imprecise isotopic palaeotemperature signatures. Here we use molecular phylogenetics and precise dating of two island species within the same clade as the continental taxa to show recent speciation in a species-rich genus characteristic of the Cape flora. The results indicate that diversification began approximately 7-8 Myr ago, coincident with extensive aridification caused by changes in ocean currents. The recent origin of endemic species diversity in the Cape flora shows that large continental bursts of speciation can occur rapidly over timescales comparable to those previously associated with oceanic island radiations.

The value of pulmonary artery and central venous monitoring in patients undergoing abdominal aortic reconstructive surgery: a comparative study of two selected, randomized groups.

One hundred two patients undergoing abdominal aortic reconstructive surgery were prospectively, randomly allocated to two groups, one of which was monitored with a central venous catheter and the other with a pulmonary artery catheter. Patients with uncompensated cardiopulmonary or renal disease were excluded from the study. General anesthesia was administered for the surgical procedure, and the patients were followed through hospital discharge. No statistically significant differences occurred between the two groups with regard to morbidity (perioperative cardiac, pulmonary or renal sequelae), mortality rate, duration of intensive care, postoperative hospital stay, or cost of hospitalization. The one statistically significant difference between groups was the professional fee charged for anesthetic care, which was higher for patients with pulmonary artery catheters than for those with central venous catheters. In conclusion, we prospectively gathered data from most patients presented for abdominal aortic reconstructive surgery. Our data seem to indicate that the choice of central venous catheter or pulmonary artery catheter monitoring makes little difference in outcome after abdominal aortic reconstructive surgery, and that for many patients pulmonary artery catheters are not necessary to give appropriate, adequate care. Because of the size of the sample, however, declarations of epidemiologic significance would be unfounded. Therefore large-scale, multicenter studies addressing such outcomes remain necessary.

Intraoperative urinary output and postoperative blood urea nitrogen and creatinine levels in patients undergoing aortic reconstructive surgery.

Urinary output has been used as a measure of adequate renal perfusion during anesthesia and surgery. In this study, 40 consecutive patients undergoing elective aortic reconstruction were studied to determine whether intraoperative urinary output was predictive of postoperative renal function as measured by blood urea nitrogen (BUN) and creatinine concentrations on postoperative days 1, 3 and 6, or 7. Pulmonary capillary wedge pressures or central venous pressures were kept at or above preoperative values. All patients received 22.5 g of mannitol IV prior to aortic crossclamping. No significant correlation was noted between either mean intraoperative urine output or lowest hourly urine output and postoperative BUN and creatinine concentrations. Complete interruption of renal blood flow in nine of the 40 patients had no significant effect on the correlations. Consequently, intraoperative urine output does not appear predictive of postoperative renal insufficiency in patients undergoing elective aortic reconstruction.

Classroom use of personal computers in medical education: a practical approach.

Classroom lectures in medical schools have traditionally employed a blackboard and slides. We have developed a compact, durable, and relatively low-priced system for computer-assisted instruction which introduces audiovisual material in a random-access manner. When this system was used in the classroom to provide flexible, clinical simulations, it promoted a high level of audience-instructor interaction and facilitated problem-based learning. The system has been used successfully in lectures in our medical school, at other medical schools, at community hospitals and at national scientific meetings.