Investigating the phytoavailability of metals in roots of Croton macrostachyus and Phytolacca dodecandra: induced rhizosphere processes.

Medicinal plants are key component of complementary and alternative medicine, and constitute the first therapeutic strategy for majority of the global population, particularly in developing nations. Croton macrostachyus and Phytolacca dodecandra are among such plants, widely used to treat various diseases. The present study aimed at investigating the elemental composition of both plant root samples collected from four districts in the Central Gondar Zone, Northwest Ethiopia. An optimized wet-digestion procedure was applied with 0.5 g of root sample using HNO3: HCl: H2O2 (v/v) in the ratio of 8:2:1 at 240 °C for 3:00 h (for P. dodecandra), and 5:2:2 at 300 °C for 3:00 h (for C. macrostachyus). Then, concentrations of metals in the digested samples were determined using a flame atomic absorption spectrophotometer; and the validity of the optimized procedure was evaluated by spiking experiments. Results showed good accuracy and repeatability of the methods with percent of recoveries ranging from 85 to 103%. The mean concentrations of metals in C. macrostachyus root samples were higher than their P. dodecandra counterparts, and the distribution of metals showed the following decreasing order: Mg > Ca ≈ Fe > Mn > Zn > Cu > Cr. One-way ANOVA revealed no significant differences (p > 0.05) between the mean concentrations of the same metals in both plant root samples, except for Mg and Cr. Correlation matrix, principal component and cluster analyses suggested that accumulation of metals in the root samples originated from both natural and anthropogenic sources. In conclusion, the roots of both medicinal plants contained substantial amounts of metals, thereby serving as valuable sources of essential elements.

Phytoremediation of soils contaminated by lead and cadmium in Ethiopia, using Endod (Phytolacca dodecandra L).

Phytoremediation is a cost effective and environmentally sustainable green technology for remediation of metal contaminated sites. In Addis Ababa, the capital of Ethiopia, large vegetable farms are grown on contaminated sites. This study evaluates the potential of Phytolacca dodecandra L to remediate Pb and Cd from contaminated sites in Addis Ababa. Pb and Cd in soil samples and different plant parts were determined using AAS. Phytoremediation potential of P. dodecandra in different seasons was estimated by calculating the Bioconcentration factor (BCF) and translocation factor (TF). The average BCF recorded for plant shoot in dry season samples varied from 0.87 to 1.74 for Pb and 1.06 to 2.00 for Cd, while in wet season it was within the range of 1.1-1.53 for Pb and 0.93-3.89 for Cd. The TF values for P. dodecandra ranged from 0.84 to 3.49 for Pb and 1.81 to 4.11 for Cd in dry season, whereas for wet season it varied between 1.34 and 2.01 for Pb and 1.78 and 2.97 for Cd. Since the mean values of BCF and TF were >1, it was concluded that P. dodecandra has considerable potential for phytoextraction of Pb and Cd in contaminated sites.

Triterpenoid and Saponin Rich Phytolacca dodecandra L'Herit (Endod): A Review on Its Phytochemistry and Pharmacological Properties.

Phytolacca dodecandra L'Herit (Endod) is the most extensively studied plant among 35 known species in the genus Phytolacca (Family: Phytolaccaceae). The plant has been used as a viable treatment for various ailments, such as malaria, rabies, ascariasis, and skin disorders, in many parts of Africa. In Ethiopia, the dried and powdered Endod berries have been used for a long period of time as a detergent to clean clothes. Since the discovery of the molluscicidal activities of its berries more than five decades ago, P. dodecandra has been a research focus worldwide and several phytochemicals mainly of triterpenoids and saponins were reported. Additionally, various biological activities, including larvicidal, insecticidal, antibacterial, antifungal, and anti-inflammatory activities of its isolated compounds and crude extracts were investigated. Furthermore, some of the findings from pharmacological and phytochemical investigations were patented to be used in various medicinal formulations. The plant is still the subject of many investigations and hence, a thorough up-to-date review is required to provide comprehensive information needed for future exploitation of the plant. In this review, the phytochemical compositions and pharmacological activities are comprehensively addressed and discussed in details.

In Vitro Evaluation of the Effects of Selected Plants on the Growth of the Mycelial Form of Histoplasma capsulatum Variety farciminosum in Ethiopia.

Epizootic lymphangitis is prevalent in equines in Ethiopia, causing remarkable economic and welfare impacts but often neglected. Lack of effective treatment contributed to its continued occurrence, and hence, search for an effective treatment should be considered a priority area to minimize its impacts. Previous ethnobotanical studies have reported that Curcuma longa, Phytolacca dodecandra, and Datura stramonium were used to treat cutaneous fungal infections and reduce their incidence. The treatment effects of these plants against epizootic lymphangitis should be studied. The in vitro growth inhibitory effects of methanol extracts of the root of C. longa, berry of P. dodecandra, and leaf of D. stramonium were evaluated. Histoplasma capsulatum var farciminosum was isolated from clinical cases of epizootic lymphangitis in carthorses in central Ethiopia. The nested polymerase chain reaction was used to confirm the identity of the isolates. Serial twofold dilutions of the extract of berries of P. dodecandra and leaves of D. stramonium were done in sterile water, whereas dilution of the extract of roots of C. longa was done in dimethylsulphoxide. The effects of the plants on the growth of Histoplasma capsulatum var farciminosum were assessed by agar dilution assay. Culture media with no antifungal agent and media containing ketoconazole served as negative and positive control, respectively. The methanol extract of C. longa showed inhibitory effects at concentrations ranging from 0.07 to 5 mg/mL. Similarly, the methanol extract of P. dodecandra showed growth inhibitory effects at concentrations ranging from 0.156 to 5 mg/mL. That is, the growth inhibitory concentration of C. longa was 0.07 mg/mL, whereas that of P. dodecandra was 0.156 mg/mL. In contrast, D. stramonium showed no inhibitory effect. This preliminary observation showed that methanol extracts of C. longa and P. dodecandra showed inhibitory effects on the growth of Histoplasma capsulatum var farciminosum requiring further repeated in vitro evaluation so as to generate adequate evidence, which would justify in vivo trials.

Chemical Composition and Antimicrobial Activity of Essential Oil from Phytolacca dodecandra Collected in Ethiopia.

The essential oil from Phytolacca dodecandra, a traditional herb of Ethiopia, has been studied, including the chemical composition and antimicrobial activity. The difference between four P. dodecandra samples (P-1⁻P-4), which differed in gender or location, has also been analyzed. The essential oils were obtained by steam distillation, while the aromas were extracted by head space solid-phase microextraction (HS-SPME) and both were analyzed by gas chromatography- mass spectrometry (GC-MS). The oils' antimicrobial activities were evaluated by the microdilution method against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Candida albicans. Ninety one components, representing 88.37 to 94.01% of the aromas, were identified. The compositions of the aromas of four samples are mainly dominated by aldehydes and ketones: 2-nonanone (1.80⁻30.80%), benzaldehyde (4.99⁻25.99%), and sulcatone (2.34⁻5.87%). Sixty components representing 64.61 to 69.64% of the oils were identified, and phytone (3.04⁻21.23%), phytol (4.11⁻26.29%) and palmitic acid (1.49⁻23.87%) are the major compounds. No obvious antimicrobial activity was observed for all the four essential oils.

Publication patterns in Restorative Dentistry and Endodontics

OBJECTIVES: Restorative Dentistry and Endodontics (Restor Dent Endod; RDE) is an English-language journal published by the Korean Academy of Conservative Dentistry, and it has been online since 2012 with quarterly publications. The purpose of this paper was to review and analyze the publications in this journal since its inception and over the 7-year period from 2012 to 2018. MATERIALS AND METHODS: This paper assessed the number, type, and subject of articles published, as well as authorship patterns and article citations of the journal over a 7-year period. The citation indicator for the journal (h-index) was assessed using Google Scholar. RESULTS: The number of articles per issue has remained relatively consistent in the 7 years that were analyzed. An analysis of the article types revealed various categories of review articles. Original research articles accounted for the most articles per volume. Twice as many articles per volume were on endodontic topics than on restorative subjects. Articles published in RDE have been widely cited in Synapse, Crossref, and PubMed Central. A country-wise mapping of authors' institutions revealed significant contributions from authors around the world. With an h-index of 24, RDE ranks third among journals in its specialty. The most cited articles were open lectures on statistics and research articles on recent concepts, technology, and materials. CONCLUSION: Over the last 7 years, RDE has served as a platform for a large number of manuscripts in the field of restorative dentistry and endodontics.

Larvicidal effect of Endod (Phytolacca dodecandra) seed products against Anopheles arabiensis (Diptera: Culicidae) in Ethiopia.

OBJECTIVE: The purpose of the present study was to determine the larvicidal effect of 'Endod' (Phytolacca dodecandra) seed products on Anopheles arabiensis, in Ethiopia. RESULTS: Experimental study was conducted using a total of 2400 third instars larvae of A. arabiensis. The seed products P. dodecandra showed larvicidal activity against 3rd-stage larvae of both the laboratory and field population of A. arabiensis. The LC99 values for P. dodecandra's seed powder and its extract form against the laboratory reared larvae were 121.07, and 616.46 mg/l, respectively. The LC50 and LC95 values were also determined.

Homeopathic therapy for sleep bruxism in a child: Findings of a 2-year case report.

Bruxism is a sleep disorder characterized by grinding and biting teeth with multifactorial etiology, resulting in deleterious effects on teeth, periodontium, and temporomandibular joint. There is a lack of scientific evidence evaluating the effectiveness of medicines in treating this parafunction. The present case report was drafted under the rules of CARE checklist. An 8-year-old male patient with sleep bruxism and associated symptoms received a combined homeopathic therapy of Phytolacca decandra 12c and Melissa officinalis 12c for 2 months. After this period of combined homeopathic therapy, the bruxism and associated symptoms completely disappeared. After 2 years of clinical follow-ups, the patient had no recurrences. The use of homeopathic therapy was successful and should be seen as an alternative to treat sleep bruxism and its associated symptoms in children.

Evaluation of Endod (Phytolacca dodecandra: Phytolaccaceae) as a Larvicide Against Anopheles arabiensis, the Principal Vector of Malaria in Ethiopia.

Malaria control methods rely mostly on adult mosquito control using insecticide-treated nets and indoor residual spraying with insecticides. Plants such as endod (Phytolacca dodecandra) can potentially be used for the control of mosquito larvae as a supplement to adult control methods. Following the discovery of endod, a molluscicide plant, more than 5 decades ago in Ethiopia, subsequent studies have shown that its potency can further be increased by simple procedures such as aging endod berry powder in water. This study was conducted to evaluate the killing effect of fresh and aged endod solution against 4th-stage larvae of Anopheles arabiensis. Laboratory-reared An. arabiensis larvae exposed to different concentrations of endod preparation using distilled or spring water had 50% lethal concentration (LC(50))  =  49.6 ppm and 90% lethal concentration (LC(90))  =  234 ppm for fresh and LC(50)  =  36.4 ppm and LC(90)  =  115.7 ppm for the aged endod solution in distilled water against the laboratory population. Against field-collected larvae of the same species, aged preparations in habitat water resulted in higher LC(50) (472.7 ppm) and LC(90) (691 ppm) values, with only a slight improvement over fresh preparations in habitat water (LC(50)  =  456.2 ppm; LC(90)  =  896.1 ppm). In general, although aged preparations of endod required lower concentrations than fresh to kill at least 90% of the larvae, these concentrations were much higher (12-70×) than that required for schistosome-transmitting snails.

Anti-proliferative effects of homeopathic medicines on human kidney, colon and breast cancer cells.

OBJECTIVE: Homeopathy is controversial, due to the claims made for very high dilutions. Although several theories are proposed to understand the mechanisms of action, none are scientifically verified. This study aimed to investigate the efficacy of the selected homeopathic medicines in specific in vitro cancer models. METHODS: We assessed the cytotoxic activity of selected homeopathic medicines in mother tincture (MT), and ultramolecular dilution (30C, 200C, 1M and 10M) against cell lines deriving from tumors of particular organs, Sarsaparilla (Sars) on ACHN cells (human renal adenocarcinoma), Ruta graveolens (Ruta) on COLO-205 (human colorectal carcinoma), and Phytolacca decandra (Phyto) on MCF-7 (human breast carcinoma). Sars was also tested against Madin-Darby canine kidney (MDCK) cells (a non-malignant cell line). Cytotoxicity was measured using the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) method, anti-proliferative activity by trypan blue exclusion assay, apoptosis determined by dual staining the cells with ethidium bromide (EB) and acridine orange (AO) dyes. RESULTS: MTs and ultra-diluted preparations of the three homeopathic medicines had highly significant effects in the respective cancer cell lines, producing cytotoxicity and a decrease in cell proliferation. The effects were greatest with the MTs, but in all cases and persisted, although to a lesser degree in the ultra-diluted molecular preparations. Sars showed no effect on MDCK cells. In the homeopathic medicine treated cultures, hallmarks of apoptosis were evident including, cell shrinkage, chromatin condensation and DNA fragmentation. CONCLUSION: This study provides preliminary laboratory evidence indicating the ability of homeopathic medicines as anticancer agents. Further studies of the action of these homeopathic remedies are warranted.

Biosynthesized silver nanoparticles by ethanolic extracts of Phytolacca decandra, Gelsemium sempervirens, Hydrastis canadensis and Thuja occidentalis induce differential cytotoxicity through G2/M arrest in A375 cells.

The capability of crude ethanolic extracts of certain medicinal plants like Phytolacca decandra, Gelsemium sempervirens, Hydrastis canadensis and Thuja occidentalis used as homeopathic mother tinctures in precipitating silver nanoparticles from aqueous solution of silver nitrate has been explored. Nanoparticles thus precipitated were characterized by spectroscopic, dynamic light scattering, X-ray diffraction, atomic force and transmission electron microscopic analyses. The drug-DNA interactions of silver nanoparticles were analyzed from data of circular dichroism spectroscopy and melting temperature profiles using calf thymus DNA (CT-DNA) as target. Biological activities of silver nanoparticles of different origin were then tested to evaluate their effective anti-proliferative and anti-bacterial properties, if any, by exposing them to A375 skin melanoma cells and to Escherichia coli C, respectively. Silver nanoparticles showed differences in their level of anti-cancer and anti-bacterial potentials. The nanoparticles of different origin interacted differently with CT-DNA, showing differences in their binding capacities. Particle size differences of the nanoparticles could be attributed for causing differences in their cellular entry and biological action. The ethanolic extracts of these plants had not been tested earlier for their possible efficacies in synthesizing nanoparticles from silver nitrate solution that had beneficial biological action, opening up a possibility of having therapeutic values in the management of diseases including cancer.

Evaluation of berries of Phytolacca dodecandra for growth inhibition of Histoplasma capsulatum var. farciminosum and treatment of cases of epizootic lymphangitis in Ethiopia.

OBJECTIVE: To evaluate the berries of Phytolacca dodecandra (P. dodecandra) for its effect on Histoplasma capsulatum var. farciminosum (HCF) and for the treatment of cases of epizootic lymphangitis (EL). METHODS: Samples were collected from un-ruptured nodules of cases of EL at Debre Zeit and Akaki (central Ethiopia). Mycological culture and isolation of HCF were performed at the Aklilu Lemma Institute of Pathobiology. Phytochemical screening was done for n-butanol extract of P. dodecandra to detect alkaloids, saponins, phenolic compounds and flavonoids. The minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of aqueous and n-butanol extracts of P. dodecandra against HCF were determined by agar dilution assay. For the in vivo trial, 5% simple ointment was prepared from n-butanol extract and applied topically to 24 (twelve early and twelve moderate) cases of EL. RESULTS: Phytochemical screening showed that n-butanol extract of P. dodecandra was positive for alkaloids, saponins and phenolic compounds but negative for flavonoids. The MICs of n-butanol and aqueous extracts of P. dodecandra were (0.039%-0.078%) and (0.625%-1.250%), respectively. The MFCs of n-butanol and aqueous extracts of P. dodecandra were (0.078%-0.156%) and (1.250%-2.500%), respectively. The MIC and MFC of ketoconazole (positive control) was (1.200×10(-5)%-2.500×10(-5)%) and (5.000×10(-5)%-1.000×10(-4)%), respectively while growth was observed on free medium (negative control). From the total of 24 treated cases of EL, 14 (58.3%) responded to treatment; however, 10 (41.7%) did not respond to treatment. There was no significant difference in the degree of response to treatment between early and moderate cases (χ(2)=0.686; P=0.408). CONCLUSIONS: It can be concluded that n-butanol extract of P. dodecandra demonstrates antifungal effects while the aqueous extract shows no antifungal activity.

Equine histoplasmosis: treatment trial in cart horses in Central Ethiopia.

Therapeutic effects of Sodium Iodide (NaI), Potassium Iodide (KI), ground berries of "Endod" (Phytolacca dodecandra) and Penstrip were evaluated on 70 cases of equine hitoplasmosis (EH). Response to each treatment was assessed using clinical examination of the lesions. Statistically significant difference (P = 0.0036) in therapeutic effect was observed among the different remedies. Cases treated either with a combination of NaI and Penstrip (F = 6.34, P = 0.004) or "Endod" and Penstrip (F = 3.64, P = 0.031) demonstrated significant response. The difference in response to treatment between early and advanced cases of EH was statistically significant (t = 2.22, P = 0.0148).

Laboratory evaluation of Ethiopian local plant Phytolacca dodecandra extract for its toxicity effectiveness against aquatic macroinvertebrates.

In this study, we evaluated the toxicity effectiveness of berries crude extract of Endod [vernacular name (local native language, Amharic); Phytolacca dodecandra] against aquatic macroinvertebrates Baetidae (Mayflies) and Hydropsychidae (Caddisflies), under laboratory conditions. In Ethiopia, toxic plant, berries of Phytolacca dodecandra are being commonly used for washing clothes and to control fresh water snails. Macroinvertebrates are useful biological indicators of change in the aquatic ecosystems. The present study clearly revealed that the LC50 and LC90 values for berries crude extract of Phytolacca dodecandra against Baetidae were 181.94 and 525.78 mg/l and lethal doses (LC50 and LC90) required for Hydropsychidae were 1060.69 and 4120.4 mg/l respectively. The present investigation demonstrated that Baetidae was more susceptible than Hydropsychidae, even at shorter exposure period of 2 h. From our preliminary investigation the toxicity effectiveness of crude extracts of Phytolacca dodecandra has been clearly shown. In addition, it requires further explorations which address both the toxicity activity and the active principles that are responsible for its toxicity effectiveness. Ultimately, the release/introduction of Phytolacca dodecandra plant berries extracts into the river/streams leads to disruption of food chain in the aquatic ecosystem. Therefore, at this moment preserving the aquatic ecosystem is extremely essential and inevitable.

In vitro activity of Phytolacca dodecandra (Endod) against dermatophytes.

There is a need for better and less costly treatment of superficial mycotic infections, and one approach might be testing of'traditionally used plants for their antifungal activities as potentials for drug development. The aim of the present study was to determine the in vitro activity of Phytolacca dodecandra (Endod) on various species of dermatophytes and yeasts of medical importance. The aqueous extract from the plant P. dodecandra was tested for its antifungal activity against 33 dermatophyte and yeast strains. The minimum inhibitory concentration (MIC) was determined by adopting the broth microdilution method for testing of conidium forming filamentous fungi according to the NCCLS M38-P proposed standard with some modifications. The MIC of P. dodecandra against the dermatophytes tested ranged from 19.5 mg/l to 156.0 mg/l, while for all the yeasts the MIC was >500 mg/l. The minimum inhibitory concentration for 50% (MIC50) of the dermatophyte strains was 62.5 mg/l. The extract showed fungicidal activity against the dermatophytes that ranged from 19.5 to 312.5 mg/l. No activity was observed against the yeasts. From our preliminary results antifungal activity of P. dodecandra has been shown. This should he strengthened with more extensive studies which address both the antifungal activity and the active principle that is responsible for its fungicidal activity.

Control of Biomphalaria pfeifferi population and schistosomiasis transmission in Ethiopia using the soap berry endod (Phytolacca dodecandra), with special emphasis on application methods.

The endod (Phytolacca dodecandra)-based schistosomiasis mansoni control project was implemented in Ethiopia between 1994 and 1999. The aim was to develop an effective, cheap and sustainable method of controlling schistosomiasis. First, different formulations of the Ethiopian endod strain 44 (E-44) were compared for potency in the laboratory. Secondly, spray and drip-feeding methods were compared for simplicity and effectiveness in the field. Lastly, the efficacy of endod powder soap was compared with the endod spray method. In Bati stream, endod powder soap was distributed to the residents every weekend at laundry sites. In Worke stream, endod was sprayed along a 1-km stretch of the stream at 3-month intervals. No endod was applied in Harbu stream. The immediate and long-term effects of endod application on the snail population and schistosomal infection were determined. Using the spray method, 100% snail mortality could be obtained, and it was simpler and more effective than the drip-feeding method. Snail mortality ranged from 20 to 100% using endod soap. There was a progressive decline in the snail population and infection in Bati stream compared with Worke stream, mainly due to sustained use of endod soap. The advantages and disadvantages of the different endod delivery systems are discussed.

Community participation as an interactive learning process: experiences from a schistosomiasis control project in Zimbabwe.

A schistosomiasis control project was undertaken from 1994 to 1998 in Guruve District, Zimbabwe, based on the active involvement of local communities in the growing and application of the molluscicidal plant Phytolacca dodecandra as a supplement to other control measures such as chemotherapy and health education. The berries of P. dodecandra are highly molluscicidal to the intermediate host snails of schistosomiasis and is rapidly degradable in water. It was observed that plant care fluctuated during the study period. Only a few households participated in snail control activities, although 97% of respondents in a baseline survey had stated a willingness to take part. This invoked an investigation to explore the reality from a user perspective. Focus group discussions, semi-structured interviews and observations were used to solicit information. In spite of a cultural inclination for collective work, many reasons for low-level involvement emerged, inter alia the low perceived value of the project, demands for tangible benefits, inaccessible fields and weak leadership. This study shows that community participation is a complex process upon which a multiplicity of social and cultural determinants have an impact. If community participation is to become successful in development programmes it ought to be viewed as a mutual learning process where obstacles are identified and discussed and solutions shared among community members and project staff.

Evaluation of pilot control trial of intestinal schistosomiasis in the Finchaa Sugar Estate, Ethiopia.

Intestinal schistosomiasis is undergoing a rapid increase in magnitude in Finchaa Sugar Estate in Ethiopia. A pilot control trial of intestinal schistosomiasis was instituted in 1995 to reduce the magnitude of the disease and introduce sustainable schistosomiasis control approaches in the Sugar Estate. Following initial parasitological survey of all the camps in the Sugar Project area in 1995 using Kato method, mass chemotherapy of the heavily infected residents of Camp 7 and selective treatment of lightly infected residents of other camps were made using praziquantel. Endod (type 44) was applied to transmission sites along Fekerie stream in Camp 7 on quarterly basis whenever Biomphalaria pfeifferi was detected. Other inputs to the project as parts of capacity building included transplantation of Endod cuttings (type 44), training and health education. Cross sectional parasitological surveys were made in 1998 to assess the impact of the pilot control trial. The results of stool examination showed that the prevalence of schistosomiasis was reduced from 30% in 1995 to 26% in 1998 among residents of Camp 7 and the intensity of infection from 198 eggs per gram of feces (EPG) in 1995 to 85 EPG in 1998. Similarly, the prevalence of infection among children in Finchaa Valley Elementary School was reduced from 78% in 1994 to 56% in 1998 and the reduction in respective intensity of infection was from 283 EPG to 114 EPG. Although significant reduction in the magnitude of the disease was not achieved, the control activities were taken over by the Sugar Project Polyclinic to ensure sustainability. In addition to chemotherapy and snail control using Endod, other disease non-specific methods such as health education should be used to get maximum benefit from such facilities as latrines, and ensure participation of the community in order to sustain the control activities.

Tracing the allomerization pathways of chlorophylls by (18)O-labeling and mass spectrometry.

The Willstätter allomerization reaction of chlorophylls (Chl) has posed a difficult problem in Chl and photosynthesis research over the past 90 years. Here, we present strong additional evidence, based on (18)O-labeling and mass spectrometry, for the previously published free-radical allomerization (FRA) mechanism (Hynninen, Z. Naturforsch. 1981, 36b, 1010-1016). This mechanism is also complemented now by describing two alternative pathways for the formation of 13(2)(S/R)-hydroxy-Chl a. The results from the (18,18)O(2)-experiments suggest that the predominant route for the formation of the 13(2)(S/R)-hydroxy-Chl a under essentially anhydrous conditions (anhydrous Chl and thoroughly dried methanol) is the homolytic cleavage of the C-13(2)-hydroperoxide intermediate. However, if Chl dihydrate and undried methanol are used in the reaction mixture, the direct route from the Chl C-13(2) radical to 13(2)(S/R)-hydroxy-Chl a can be predicted to become significant. The results from the (18,18)O(2)-allomerization experiments described in this paper also verified that the 13(2)(S/R)-methoxy-lactone derivatives and the 15-glyoxylic acid derivative of Chl a incorporated each a single (18)O-atom, whereas 13(2)(R/S)-methoxy-Chl a remained unlabeled. Consequently, these allomers are formed via the pathways previously suggested in the original FRA mechanism. The possible factors contributing to the control of the allomerization reactions are considered. Finally, the relationship between the allomerization reactions of Chl a and those of Chl b and BChl a is briefly discussed.

Control of Schistosoma mansoni by the soapberry Endod (Phytolacca dodecandra) in Wollo, northeastern Ethiopia: post-intervention prevalence.

OBJECTIVES: To record the effect of Endod soap and spraying of soaked Endod suspension on the prevalence of human schistosomiasis. DESIGN: A cross-sectional epidemiological study in which pre- and post-intervention parasitological results were compared. SETTING: Kemise, Bati and Harbu towns in northeastern Ethiopia. SUBJECTS: The study subjects included all members of the five per cent households systematically selected from the three towns. RESULTS: In Kemise town, where suspension of ground Endod was sprayed on the stream containing infected snails, the prevalence of the disease was reduced from 59% to 53% and the mean intensity of infection was reduced from 239 eggs per gram (EPG) of faeces to 99 EPG (p < 0.05). In Bati town where Endod soap approach was used, the respective reduction in the prevalence and intensity of infection was from 51% to 43% and from 195 EPG to 162 EPG (p < 0.05). There was also a significant reduction of the disease in the control town probably due to the effects of praziquantel treatment and other factors. CONCLUSION: The reduction achieved in the prevalence and intensity of schistosomiasis after an intervention period of four years was limited. This observation corroborates the fact that molluscicides must always be considered as supplementary to chemotherapy in the control of schistosomiasis. Although both approaches can be used, the spraying approach appears to be simpler and more feasible because two or three times yearly application of Endod suspension would suppress snail population and reduce transmission. Nevertheless, the choice as to what approach to use must be made on the basis of community preference, and for some soap-effect of Endod would be attractive