Nephroprotective Effect of Diosmin against Cisplatin-Induced Kidney Damage by Modulating IL-1ß, IL-6, TNFα and Renal Oxidative Damage.

Cisplatin (CP) is a platinum compound of the alkylating agent class that is used for the treatment of various types of cancer. However, CP treatments in cancer patients are accountable for nephrotoxicity, as it is a major adverse effect. Hence, this research study was proposed to investigate the nephroprotective effect of diosmin, a flavonoid glycoside of hesperidin derivatives against cisplatin-induced kidney damage. Wistar rats received a single intraperitoneal (i.p) injection of CP (7.5 mg/kg, i.p) to induce nephrotoxicity. The administration of CP significantly (p < 0.001) increased the markers of kidney function test (creatinine, blood urea nitrogen, and uric acid) and demonstrated histopathological changes in the kidney of the CP-treated nephrotoxic group. In addition, the CP-treated nephrotoxic group demonstrated a significant (p < 0.001) increase in lipid peroxidation (LPO) levels and depleted activities of reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT).However, diosmin (100 and 200 mg/kg) treatments significantly reduced the elevated levels of kidney function test parameters and restored structural changes in the kidney (p < 0.001). The administration of diosmin (100 and 200 mg/kg) significantly (p < 0.001) reduced LPO levels, increased GSH content and showed improvements in the activities of GPx, GR, SOD and CAT. The markers of inflammatory cytokines such as IL-1ß, IL-6 and TNFα significantly (p < 0.001) increased in the CP-treated nephrotoxic group, whereas diosmin (100 and 200 mg/kg) treatments significantly (p < 0.001) reduced the elevated levels of these cytokines. The findings of this research demonstrate the nephroprotective effect of diosmin against CP-induced kidney damage. Therefore, we conclude that diosmin may be used as a supplement in the management of nephrotoxicity associated with CP treatments in cancer patients.

Characterization of Pepper leafroll chlorosis virus, a New Polerovirus Causing Yellowing Disease of Bell Pepper in Saudi Arabia.

During the growing seasons of 2014 through 2016, a total of 336 leaf samples from bell pepper (showing leafroll and interveinal yellowing) and arable weeds were collected from Riyadh region, Saudi Arabia. The use of a polerovirus generic reverse transcription (RT)-PCR assay confirmed their presence in the bell pepper samples. Sequencing of the generic amplicon revealed high similarity (87.6 to 98.1% in nt) with four poleroviruses; Tobacco vein distorting virus, Pepper vein yellows virus, Pepper yellows virus, and Pepper yellow leaf curl virus. To further characterize one of these isolates (105D), a larger part of the genome (∼1,300 nt) spanning approximately from the 3' end of ORF2 to the middle of ORF3, was amplified and sequenced. Blasting the resulting sequence revealed the low amino acid and nucleotide identity percentages in the coat protein and movement protein partial genes with viruses deposited in GenBank. Next-generation sequence was used to acquire a larger part of the genome, which resulted in the reconstruction of isolate 105D's partial genome (5,496 nt). Sequence similarity analysis revealed the presence of a divergent polerovirus isolate belonging to a new species that was tentatively named Pepper leafroll chlorosis virus (PeLRCV). Using a specific RT-PCR assay for this isolate confirmed the presence of this new viral species in the symptomatic peppers. Aphid transmission experiments showed that PeLRCV is vectored by Aphis gossypii and that it can infect at least five out of the 15 different plants species tested. Based on our findings, PeLRCV is a new member of genus Polerovirus in the family Luteoviridae.

New Approach of Beauveria bassiana to Control the Red Palm Weevil (Coleoptera: Curculionidae) by Trapping Technique.

This work is the first study to investigate the efficacy of the commercial formulation of Beauveria bassiana (Broadband) to control adults of red palm weevil (Rhynchophorus ferrugineus (Olivier)). This fungus could be applied as one of the biological tactics in controlling red palm weevil. Bioassay experiments for medium lethal concentrate and medium time to cause death of 50% of red palm weevil adults were carried out. The result showed that the LC50 of B. bassiana (Broadband) was 2.19×10(7) and 2.76×10(6) spores/ml at 9 and 23 d of treatment, respectively. The LT50 was 13.95 and 4.15 d for concentration of 1×10(7) and 1×10(8) spores/ml, respectively, whereas 1×10(9) spores/ml caused 100% mortality after 24 h. Additionally, a red palm weevil pheromone trap was designed to attract the adults to be contaminated with spores of Broadband, which was applied to the sackcloth fabric that coated the internal surfaces of the bucket trap. The mating behavior was studied to determine direct and indirect infection of the spores from male to female and vice versa. The results showed a high efficacy of Broadband suspension at 1×10(9) spores/ml; 40 ml of suspension at this concentration treated to cloth in a trap caused death of contaminated adults with B. bassiana spores directly and indirectly. The 100% mortality was obtained even after 13 d of traps treatment with 40 ml of the suspension at 1×10(9) spores/ml.

First Report of Watermelon chlorotic stunt virus Infecting Watermelon in Saudi Arabia.

In the Saudi Arabian deserts, watermelon [Citrullus lanatus (Thunb.)] is cultivated in the lowlands and wadis (washes) where water accumulates following rainfall, and where heat, salt, and drought stress are common constraints on production. During the spring of 2014, watermelon leaves exhibited yellowing and severe chlorotic mottling symptoms. The foliar symptoms were reminiscent of Watermelon chlorotic stunt virus (WmCSV), a bipartite begomovirus previously reported in several neighboring countries (1,3). Ten samples were collected from three farms in the Leith region, where 100% of the watermelon plants were symptomatic. Total nucleic acids were extracted from the symptomatic watermelon plants and were subjected to PCR using WmCSV DNA-A specific primers designed based on a complete genome sequence (GenBank Accession No. AJ012081), WmCSVF-3'-CGTGCTGTTGCCCCCACTGT-5' and WmCSVR-3'-CCTGCATATCTCGTGCCAGAATC-5' to obtain an expected size fragment of 1,111 bp located between the nucleotide (nt) coordinates 400-1510. The amplicons (one per sample) were cloned, and the DNA sequence was determined for each and used to search the NCBI database. The top hits for sequences obtained from all 10 samples were to WmSCV sequences, with shared nt identity values of 97 to 98%. To clone the full-length begomoviral DNA-A and DNA-B components, nucleic acids were subjected to rolling circle amplification (RCA) (2). The RCA products were cloned into the pGEM7 plasmid vector using the unique restriction sites, identified as HindIII for DNA-A, and as EcoRI for DNA-B, respectively. Ten DNA-A clones and two DNA-B component clones were sequenced. The DNA-A components ranged in size from 2,751 (KM066100) to 2,752 bp (KJ939448), whereas the DNA-B components were 2,757 bp in size (KJ939447). Analysis of the viral sequences from the DNA-A clones indicated they had the characteristics of a typical genome of a begomovirus DNA-A component that consist of a hairpin stem-loop structure in the intergenic region, two tandem copies of the iteron (TGGAGAC) located between the nt coordinates 2675 and 2680, 2682 and 2688 predicted to be involved in Rep binding, and six predicted genes encoding proteins with high sequence identity to those encoded by other WmCSV isolates. The 10 DNA-A component sequences were aligned with sequences for previously described WmCSV isolates available in GenBank using Muscle, followed by pairwise comparisons using SDT software (4). The analysis revealed that the cloned DNA-A components shared 99 to 100% nt sequence identity with each other, and 97 to 98% nt identity with WmCSV isolates reported from Yemen (AJ012081), Jordan (EU561237), Iran (AJ245652), and Sudan (AJ245650). Further, the WmCSV DNA-B from Saudi Arabia shared the highest nt identity with sequences from Yemen (AJ012082) at 96%, Iran (AJ245653) at 95%, and only 94% with DNA-B from both Sudan (AJ245651) and Jordan (EU561236). To our knowledge, this is the first report of WmCSV in Saudi Arabia. WmCSV poses a serious threat to the production of this highly valued crop in Saudi Arabia and considerably reduces crop yield (1). References: (1) I. D. Bedford et al. Eur. J. Plant Pathol. 100:243, 1994. (2) A. Idris et al. Plant Dis. 97:910, 2007. (3) A. Kheyr-Pour et al. Phytopathology 90:629, 2000. (4) B. Muhire et al. Arch. Virol. 158:1411, 2013.

First Report of Tomato spotted wilt virus in Lettuce Crops in Saudi Arabia.

A survey for viruses in open field lettuce crops was carried out in March 2014 in the Al-Uyaynah area, central region of Saudi Arabia. In one plot, more than 50% of the lettuce plants (Lactuca sativa; hybrid: Romaine), with the majority of the affected plants in the edges of the plot, were showing virus-like symptoms such as necrotic lesions, necrosis of the lamina of the younger leaves, and leaf curling, indicating a possible infection by a Tospovirus, possibly Tomato spotted wilt virus (TSWV). Most of them were dead when the field was visited again 3 weeks later. Samples from 10 symptomatic and two asymptomatic plants were collected. Five of the samples from symptomatic and two from asymptomatic plants were mechanically inoculated onto Nicotiana benthamiana and N. glutinosa (three indicator plants of each species were used for each sample) using 0.1 M phosphate buffer (pH 7) containing 0.01M Na2SO3 mM. All the symptomatic lettuce samples were also tested serologically using polyclonal antisera (3) against TSWV, CMV, and by using monoclonal antibodies against potyviruses. Moreover, total RNA was extracted (1) and detection of TSWV was also attempted with reverse transcription (RT)-PCR using species specific primers (4) for a 276-bp fragment of the L RNA segment. In both serological and molecular methods, positive and negative controls were included. All the mechanically inoculated plants with tissue from the symptomatic lettuce plants of N. benthamiana showed chlorotic local lesions followed by systemic top necrosis 2 to 3 weeks post inoculation. Similarly, all inoculated N. glutinosa plants showed necrotic local lesions followed by systemic chlorosis. However, all the indicator plants mechanically inoculated with tissue from asymptomatic lettuce plants gave no reaction. All the symptomatic lettuce samples reacted positively, while asymptomatic samples reacted negatively in ELISA tests with TSWV antiserum and the presence of the virus was further confirmed by RT-PCR by using specific primers (method A) (4). PCR products of two randomly selected positive samples were directly sequenced and BLAST analysis of the obtained sequences (Accession Nos. KJ701035 and KJ701036) revealed 99% nucleotide and 100% amino acid identity with the deposit sequence in NCBI from South Korea (KC261947). Regarding mechanical inoculation, 10 days post-inoculation, both indicator plants showed typical symptoms of TSWV infection, such as necrotic local lesions, systemic necrotic patterns, and leaf deformation. None of the symptomatic plants was found to be infected with either CMV or potyvirus. To our knowledge, this is the first report of TSWV naturally infecting lettuce in Saudi Arabia; therefore, insect vector and weed management are necessary measures to control the virus spread to other crops such as tomato and pepper (2). References: (1) E. Chatzinasiou et al. J. Virol. Meth. 169:305, 2010. (2) E. K. Chatzivassiliou. Plant Dis. 92:1012, 2008. (3) E. K. Chatzivassiliou et al. Phytoparasitica 28:257, 2000. (4) R. A. Mumford et al. J. Virol. Meth. 46:303, 1994.

Meta-analysis of the use of sterilized mosquito net mesh for inguinal hernia repair in less economically developed countries.

Background: Inguinal hernias are common in less economically developed countries (LEDCs), and associated with significant morbidity and mortality. Tension-free mesh repair is the standard treatment worldwide. Lack of resources combined with the high cost of commercial synthetic mesh (CSM) have limited its use in LEDCs. Sterilized mosquito net mesh (MNM) has emerged as a low-cost, readily available alternative to CSM. The aim of this systematic review and meta-analysis was to evaluate the safety and efficacy of MNM for the use in hernia repair in LEDCs. Methods: A systematic review and data meta-analysis of all published articles from inception to August 2018 was performed. Cochrane Central Register of Controlled Trials, MEDLINE and Embase databases were searched. The primary outcome measure was the overall postoperative complication rate of hernia repair when using MNM. Secondary outcome measures were comparisons between MNM and CSM with regard to overall complication rate, wound infection, chronic pain and haematoma formation. Results: A total of nine studies were considered relevant (3 RCTs, 1 non-randomized trial and 5 prospective studies), providing a total cohort of 1085 patients using MNM. The overall complication rate for hernia repair using MNM was 9·3 per cent. There was no significant difference between MNM and CSM regarding the overall postoperative complication rate (odds ratio 0·99, 95 per cent c.i. 0·65 to 1·53; P = 0·98), severe or chronic pain (OR 2·52, 0·36 to 17·42; P = 0·35), infection (OR 0·56, 0·19 to 1·61; P = 0·28) or haematoma (OR 1·05, 0·62 to 1·78; P = 0·86). Conclusion: MNM has a low overall postoperative complication rate and is unlikely to be inferior to CSM in terms of safety and efficacy. MNM is a suitable low-cost alternative to CSM in the presence of financial constraint.

Insights into the Incidence of Watermelon chlorotic stunt virus Causing Yellowing Disease of Watermelon in Western and Southwestern Regions of Saudi Arabia.

During the spring season of 2014, a total of 148 melon and watermelon leaf samples were collected from symptomatic and asymptomatic plants in the western and southwestern regions of Saudi Arabia and were tested for the presence of Watermelon chlorotic stunt virus (WmCSV) and other suspected cucurbit viruses by double antibody sandwich enzyme-linked immunosorbent assays. Ninety-eight samples were found to be positive for the presence of WmCSV, nine samples were positive for the presence of Cucurbit yellow stunting disorder virus (CYSDV), and 22 showed a mixed infection with both WmCSV and CYSDV. No other cucurbit viruses were detected in any of the samples. Host range experiments revealed that eight out of fourteen tested plant species were susceptible to WmCSV. PCR products of approximately 1.2 kb were obtained after amplification using primers specifically targeting the coat protein region of WmCSV. Positive PCR results were confirmed by dot blot hybridization. Coat protein gene sequences from eleven WmCSV isolates indicated that the highest identity was between the 104WMA-SA isolate from the Wadi Baish location and a previously reported isolate from the AL-Lith location in Saudi Arabia. The lowest identity was observed between the 42WMA-SA isolate and an isolate from Palestine.

Momordica charantia is a Weed Host Reservoir for Papaya ringspot virus Type P in Jamaica.

Papaya rinsgpot virus type P (PRSV), a member of the genus Potyvirus in the family Potyviridae, is primarily transmitted by aphids in a nonpersistent manner (2). The virus is geographically widespread but has a narrow host range within the plant families Caricaceae, Chenopodiaceae, and Cucurbitaceae (2). The first reported epidemic of PRSV in Jamaica was during the late 1980s (1). Since then, the virus has spread across the island and is recognized as a potential problem for continued production of papaya (Carica papaya L.). In the summers of 1999 and 2000, prominent vein clearing symptoms were observed on leaves of a common weed, cerasee (Momordica charantia L.), in papaya orchards of western Jamaica. This weed, a climbing annual in the Cucurbitaceae family used in a variety of local herbal preparations, was found to be growing on fences or the ground along the periphery of the orchards. Leaf samples were collected and tested for PRSV by double-antibody sandwich (DAS)-ELISA with polyclonal antibodies (Agdia Inc, Elkhart, IN). In addition, crude sap extracts from 12 cerasee leaf samples that were diluted 1:20 were mechanically inoculated onto six plants each of cerasee and papaya. Within 2 weeks, vein clearing symptoms were observed on cerasee and symptoms (vein clearing followed by mosaic development and leaf distortions) typical of PRSV infection were obtained on papaya (2). All original leaf samples and inoculated plants tested positive in DAS-ELISA. In subsequent vector transmission tests, 10 healthy cerasee or papaya seedlings were inoculated with aphids (Aphis gossypii) that were previously permitted to feed on PRSV-infected papaya or cerasee. High rates of virus transmission were achieved in three tests from cerasee to papaya (77 to 83%), papaya to cerasee (90 to 93%), and cerasee to cerasee (60 to 70%). Total RNA from papaya samples was subjected to reverse transcriptase-PCR using primers to the capsid protein gene (3). A single fragment of the expected size (approximately 996 bp) was amplified and sequenced and showed high nucleotide identity (90.3 to 91.4%) with previously reported PRSV type P from Jamaica (GenBank Accession No. DQ104823), Cuba (GenBank Accession No. DQ089482), Florida (GenBank Accession No. AF196839), Brazil (GenBank Accession No. AF344650), and Hawaii (GenBank Accession No. S46722). To our knowledge, this is the first report of the natural occurrence of PRSV on a weed host in Jamaica. Because of its widespread distribution and potential of serving as a reservoir of PRSV, cerasee may play a role in the epidemiology of PRSV. References: (1) M. Chin et al. Jam. J. Sci. Technol. 14:58, 2003. (2) D. Purcifull et al. No 292 in: Descriptions of Plant Viruses. CMI/AAB, Surrey, England, 1984. (3) J. Slightom. Gene 100:251, 1991.

A review of medicinal plant research at the University of the West Indies, Jamaica, 1948-2001.

This review summarizes research carried out on Jamaican medicinal plants at the Faculty of Pure and Applied Science, The University of the West Indies (UWI), Mona, Jamaica, between 1948 and 2001. The plants identified as being medicinal are listed along with their folk use and a summary of the scientific research done at UWI leading to the identification of natural products (NPs) and determination of their bioactivity. Natural product research on Jamaican medicinal plants began with the inception of UWI in 1948, leading to many postgraduate degrees being awarded (22 MPhil and 31 PhD). At least 334 plant species growing in Jamaica have been identified as having medicinal qualities, 193 of these have been tested for their bioactivity. Crude extracts from 80 of these plants have reasonable bioactivity and natural products (NP) have been identified from 44 plants. At least 29 of these NPs were found to be bioactive. Only 31 of the plants tested at UWI are endemic to Jamaica. Of these 23% were bioactive, as compared to 11% of the non-endemics. Based on these results, patents have been obtained and drugs have been developed. This review represents the first attempt to gather this information together in one place.

Field Resistance of Coat Protein Transgenic Papaya to Papaya ringspot virus in Jamaica.

Transgenic papayas (Carica papaya) containing translatable coat protein (CPT) or nontranslatable coat protein (CPNT) gene constructs were evaluated over two generations for field resistance to Papaya ringspot virus in a commercial papaya growing area in Jamaica. Reactions of R0 CPT transgenic lines included no symptoms and mild or severe leaf and fruit symptoms. All three reactions were observed in one line and among different lines. Trees of most CPNT lines exhibited severe symptoms of infection, and some also showed mild symptoms. R1 offspring showed reactions previously observed with parental R0 trees; however, reactions not previously observed or a lower incidence of the reaction were also obtained. The transgenic lines appear to possess virus disease resistance that can be manipulated in subsequent generations for the development of a product with acceptable commercial performance.

The Economic Impact of Managing Late Presentation of Developmental Dysplasia of Hip (DDH).

Delayed presentation of Developmental Dysplasia of Hip (DDH) comes with challenges in treatment as well as high surgical cost. Therefore the objective of this study is to quantify the economic impact of management of late presentation of DDH during a last 3-year period. We conducted a retrospective study with analysis of DDH cases managed between years 2012 to 2014. Early and late presentations of DDH were identified and cost management for both was estimated. Out of twenty-four DDH cases, thirteen cases fulfilled the inclusion criteria. All were female with majority of them presenting with unilateral DDH predominantly of the left hip. Most patients presented after age of six months and the principal complaint was abnormal or limping gait. The grand total cost for managing DDH during the three years period was USD 12,385.51, with 86% of the amount having been used to manage late presentation of DDH that was mostly contributed by the cost of surgery. We concluded that delayed presentation of DDH contributes heavily to high national expenditure. Early detection of DDH cases with systematic neonatal screening may help to minimize the incidence of the late presenting DDH and subsequently reduce the economic burden to the government.

Ecology and genetics of tropical rhizobia species.

Biological nitrogen fixation (BNF) technology with special reference to Rhizobium-legume symbiosis is growing very rapidly with the hope of combatting world hunger by producing cheaper protein for animal and human consumption in the Third World. One can see rapid progress made in the biochemistry and molecular biology of symbiotic nitrogen fixation in general; however, less progress has been made on the ecological aspects despite the fact that an enormous amount of literature is available on inoculation problems and on agronomic aspects of symbiotic nitrogen fixation. So far most information on Rhizobium concerns fast-growing rhizobia and their host legume. Although it is essential that food production using BNF technology should be maximized in the Third World, the least work has been done on slow-growing rhizobia, which are generally found in tropical and sub-tropical soils. The majority of the developing countries are in tropical and sub-tropical regions. Except for R. japonicum, a microsymbiont partner of soybean (Glycine max), the majority of the slow-growing rhizobia belong to the cowpea group, and we refer to cowpea rhizobia as tropical rhizobia species. In this review we have tried to consolidate the recent progress made on ecology and genetics of tropical rhizobia. By using recombinant DNA technology techniques it is expected that super strains of rhizobia with desirable characteristics can be produced. One must evaluate the efficiency and effectiveness of these genetically manipulated laboratory strains under field conditions. In conclusion, if one aims at combatting hunger in the Third World using BNF technology, an intensive research programme on fundamental and applied aspects of tropical rhizobia species is suggested. This involves close cooperation between molecular biologists and microbial ecologists.

Food processing methods influence the glycaemic indices of some commonly eaten West Indian carbohydrate-rich foods.

Glycaemic index (GI) values for fourteen commonly eaten carbohydrate-rich foods processed by various methods were determined using ten healthy subjects. The foods studied were round leaf yellow yam (Dioscorea cayenensis), negro and lucea yams (Dioscorea rotundata), white and sweet yams (Dioscorea alata), sweet potato (Solanum tuberosum), Irish potato (Ipomoea batatas), coco yam (Xanthosoma spp.), dasheen (Colocasia esculenta), pumpkin (Cucurbita moschata), breadfruit (Artocarpus altilis), green banana (Musa sapientum), and green and ripe plantain (Musa paradisiaca). The foods were processed by boiling, frying, baking and roasting where applicable. Pure glucose was used as the standard with a GI value of 100. The results revealed marked differences in GI among the different foods studied ranging from 35 (se 3) to 94 (se 8). The area under the glucose response curve and GI value of some of the roasted and baked foods were significantly higher than foods boiled or fried (P<0.05). The results indicate that foods processed by roasting or baking may result in higher GI. Conversely, boiling of foods may contribute to a lower GI diet.

[Growth inhibition by antibiotics and the production of resistance to them in a population of Nostoc linckia]. / Ingibirovanie antibiotikami rosta i poluchenie ustoichivosti k nim v populiatsii Nostoc linckia

Increasing concentrations of penicillin and streptomycin inhibited the growth of the blue-green alga Nostoc linckia. Although the alga could build up resistance to higher concentrations of penicillin (1000 mcg/ml), it was very sensitive to streptomycin beyond a concentration of 0.02 mcg/ml. Two stable mutants, one resistant to 1000 mcg penicillin/ml and another to 0.02 mcg streptomycin/ml were isolated, of which the latter had lost its nitrogen fixing capacity. Drug resistance seems to be due to nuclear or gene mutation.

Thermal susceptibility of Streptococcus faecium strains isolated from frankfurters.

The heat resistance of nine strains of Streptococcus faecium isolated from frankfurters was determined at 63 and 68 degrees C in brain heart infusion broth. Exponential-phase cultures (approximately 10(7) colonies/mL) were used as inoculants. The heat resistance of S. faecium DP2181, a moderately resistant isolate, was further examined in broth (55, 63, and 68 degrees C) and frankfurter emulsion (63 and 68 degrees C). The decimal reduction times (D values) were determined by regression. In broth, both time-temperature combinations resulted in a 3-4 log decline in bacterial numbers for the nine S. faecium strains tested. For S. faecium DP2181, the survivor curves deviated from the logarithmic order of death at all three heating temperatures. An initial slow period of death was evident at 55 degrees C and a resistant tail of organisms was observed at 55, 63, and 68 degrees C. The D55D63, and, D68 values for the logarithmic portion of the corresponding survivor curves were 105.6, 9.36, and 3.34 min, respectively. The survival of DP2181 was enhanced by the frankfurter emulsion. The results indicate that populations of S. faecium existed that were very heat resistant and could survive normal frankfurter processing if initially present in high numbers.

Bacteriological conditions of a Jamaican chicken hatchery.

The bacteriological profile of a chicken hatchery in Jamaica was examined. The bacterial numbers in each room of the hatchery and the effect of washing with disinfectant on the bacterial population were determined. A representative number of the bacterial isolates before and after washing the hatchery was identified. The results indicate that, while washing with quaternary ammonium compounds did not affect the Gram-negative bacteria, the number of Gram-positive bacteria was significantly decreased. Bacteria of the genera Pseudomonas, Plesiomonas and Enterobacter were predominant in the post-washing flora. The water used to wash the hatchery was contaminated and therefore a possible source of contamination.

Interaction between aminoglycoside uptake and ribosomal resistance mutations.

Mutants resistant to the 2-deoxystreptamine aminoglycosides hygromycin B and gentamicin were analyzed biochemically and genetically. In hygromycin B-resistant strains, ribosomal alterations were not detectable by electrophoretic or genetic experiments. Rather, as was demonstrated for one strain in detail, resistance to this drug seems to be the consequence of several mutations, each impairing drug accumulation, namely of a deletion of a gene close to the proC marker which potentiates the effect of a second mutation in the unc gene cluster. Three mutants resistant to gentamicin which were previously demonstrated to harbor an altered ribosomal protein, L6, were shown in addition to contain unc. Both the unc and the ribosomal mutation greatly impair the drug accumulation ability of the mutants. Further evidence for the direct effect of ribosomal mutations on the uptake of aminoglycosides was obtained with strains that possess ribosomes with increased affinity for dihydrostreptomycin. Dihydrostreptomycin transport by these cells is greatly stimulated; thus, the hypersensitivity of these mutants is caused by increased binding affinity for dihydrostreptomycin and its secondary effect on the uptake process. Experiments were also performed on the biochemical basis of the third phase of aminoglycoside transport (acceleration phase). The condition for its onset is that ribosomes are active in protein synthesis irrespective of whether the proteins synthesized are functional. This, and the failure to observe the synthesis of new proteins upon the addition of aminoglycosides, do not support the view of autoinduction of a cognate or related transport system.

Cowpea rhizobia producing dark nodules: use in competition studies.

During a program of screening rhizobia from West Africa, it was found that some strains produced nodules of unusually dark appearance on cowpeas, but not on peanuts, soybeans, pigeon peas, or mung beans. The dark pigmentation was in the bacteroid zone, was not correlated with nodule effectiveness, and was additional to the leghemoglobin pigment. Only rhizobial strains with a nongummy ("dry") colony morphology produced dark nodules. Visually distinguishable pink and dark nodules formed on the same root when a mixture of pink and dark strains was applied as inoculum. The dark-nodule phenotype was therefore appraised as a marker and found to be useful for studying nodulation competition with strains of the orthodox pink-nodule type. The competitiveness of 10 pink-nodule strains was examined relative to a black-nodule strain, IRc 256; a range of competitiveness was obtained of less competitive than, equally competitive to, or more competitive than IRc 256. Patterns of primary (early) nodulation were generally the same as patterns of secondary (later) nodulation. Mixed infections by dark and pink strains produced piebald nodules, the frequency of occurrence of which was much greater among primary than among secondary nodules.

A review of medicinal plant research at the University of the West Indies, Jamaica, 1948-2001

This review summarizes research carried out on Jamaican medicinal plants at the Faculty of Pure and Applied Science, The University of the West Indies (UWI), Mona, Jamaica, between 1948 and 2001. The plants identified as being medicinal are listed along with their folk use and a summary of the scientific research done at UWI leading to the identification of natural products (NPs) and determination of their bioactivity. Natural product research on Jamaican medicinal plants began with the inception of UWI in 1948, leading to many postgraduate degrees being awarded (22 MPhil and 31 PhD). At least 334 plant species growing in Jamaica have been identified as having medicinal qualities, 193 of these have been tested for their bioactivity. Crude extracts from 80 of these plants have reasonable bioactivity and natural products (NP) have been identified from 44 plants. At least 29 of these NPs were found to be bioactive. Only 31 of the plants tested at UWI are endemic to Jamaica. Of these 23were bioactive, as compared to 11of the non-endemics. Based on these results, patents have been obtained and drugs have been developed. This review represents the first attempt to gather this information together in one place.

El presente trabajo resume la investigación sobre plantas medicinales jamaicanas, llevada a cabo en la Facultad de Ciencias Puras y Aplicadas de la Universidad de West Indies (UWI), Mona, Jamaica, entre 1948 y 2001. Las plantas identificadas como medicinales se enumeran junto con su uso popular y un resumen de la investigación científica realizada en UWI, la cual condujo a la identificación de los productos naturales y la determinación de su bioactividad. La investigación de productos naturales que tuvo por objeto las plantas medicinales jamaicanas, comenzó con la fundación de UWI en 1948, y en el transcurso de su desarrollo, condujo a la obtención de numerosos grados científicos. (Para el año 2001, en la Facultad de Ciencias Puras y Aplicadas se habían defendido 22 maestrías y 31 doctorados asociados con dicha investigación.) Por lo menos 334 especies de plantas que crecen en Jamaica han sido identificadas como poseedoras de propiedades medicinales, 193 de las cuales han sido sometidas a prueba para determinar su bioactividad. Los extractos crudos de 80 de estas plantas poseen una bioactividad razonable, y se han identificado productos naturales (PN) en 44 plantas. Se halló que por lo menos 29 de estos PN son bioactivos. Sólo 31 de las plantas sometidas a prueba en UWI eran endémicas de Jamaica. De éstas, el 23% resultó ser bioactivo, en comparación con el 11% en el caso de las plantas no endémicas. Sobre la base de estos resultados, se han obtenido patentes, y se han desarrollado medicamentos. Este resumen representa un primer intento por compilar esta información en un solo trabajo.