Diprenylated chalcones and other constituents from the twigs of Dorstenia barteri var. subtriangularis

The twigs of Dorstenia barteri var. subtriangularis yielded three diprenylated chalcones: (-)-3-(3,3-dimethylallyl)-5'-(2-hydroxy-3-methylbut-3-enyl)-4,2',4'-trihydroxychalcone, (+)-3-(3,3-dimethylallyl)-4',5'-[2'-(1-hydroxy-1-methylethyl)-dihydrofurano]-4,2'-dihydroxychalcone and 3,4-(6",6"-dimethyldihydropyrano)-4',5'-[2',-(1-hydroxy-1-methylethyl)-dihydrofurano]-2'-hydroxychalcone for which the names bartericins A, B and C, respectively, are proposed. Stipulin, beta-sitosterol and its 3-beta-D-glucopyranosyl derivative were also isolated. The structures of these secondary metabolites were determined on the basis of spectroscopic analysis, especially, NMR spectra in conjunction with 2D experiments, COSY, HMQC and HMBC. The structural relationship of bartericins B and C was further established by the chemical cyclization of one to the other.     

Homoisoflavonoids and xanthones from the tubers of wild and in vitro regenerated Ledebouria graminifolia and cytotoxic activities of some of the homoisoflavonoids

Eleven homoisoflavonoids and two xanthones were isolated and characterized from the bulbs of Ledebouria graminifolia. Five of the homoisoflavonoids are new compounds and were identified as: 5-hydroxy-7-methoxy-3-(4'-hydroxybenzyl)-4-chromanone, 5-hydroxy-6,7-dimethoxy-3-(4'-hydroxybenzyl)-4-chromanone, 5,7,8-trimethoxy-3-(4'-hydroxybenzyl)-4-chromanone, 5-hydroxy-3',4',7-trimethoxyspiro[2H-1-benzopyran-7'-bicyclo[4.2.0]octa-trien]-4-one, 5,7-dihydroxy-3',4'-dimethoxyspiro[2H-1-benzopyran-7'-bicyclo[4.2.0]octa-trien]-4-one. Structures were elucidated by extensive 1D, and 2D NMR spectroscopy and HRMS. A method for tissue culture was developed and the bulbs of mature plants were found to contain all the compounds isolated from the wild specimens of L. graminifolia.     

Tobacco-Related Mortality among Persons with Mental Health and Substance Abuse Problems

The rate of cigarette smoking is greater among persons with mental health and/or substance abuse problems. There are few population-based datasets with which to study tobacco mortality in these vulnerable groups. The Oregon Health Authority identified persons who received publicly-funded mental health or substance abuse services from January 1996 through December 2005. These cases were then matched to Oregon Vital Statistics records for all deaths (N= 148,761) in the period 1999-2005. The rate of tobacco-related death rates was higher among persons with substance abuse problems only (53.6%) and those with both substance abuse and mental health problems (46.8%), as compared to the general population (30.7%). The rate of tobacco-related deaths among persons with mental health problems (30%) was similar to that in the general population. Persons receiving substance abuse treatment alone, or receiving both substance abuse and mental health treatment, were more likely to die and more likely to die prematurely of tobacco-related causes as compared to the general population. Persons receiving mental health services alone were not more likely to die of tobacco-related causes, but tobacco-related deaths occurred earlier in this population.     

Treatment-enhanced CD4+Foxp3+ glucocorticoid-induced TNF receptor family related high regulatory tumor-infiltrating T cells limit the effectiveness of cytokine-based immunotherapy

Regulatory T cells can suppress activated CD4+ and CD8+ T effector cells and may serve as an impediment to spontaneous or therapeutic type 1 antitumor immunity. In a previous study, we observed minimal therapeutic impact, but significantly enhanced T cell cross-priming and lesional infiltration of tumor-reactive CD8+ T cells into established CMS4 sarcomas after combined treatment of BALB/c mice with rFLt3 ligand (rFL) and recombinant GM-CSF (rGM-CSF). In this study, we show that this cytokine regimen also results in the profound enhancement of CD4+ tumor-infiltrating lymphocytes (TIL) expressing FoxP3, IL-10, and TGF-beta mRNA, with 50 or 90% of CD4+ TIL coexpressing the CD25 and glucocorticoid-induced TNFR family related molecules, respectively. Intracellular staining for Foxp3 protein revealed that combined treatment with rFL plus rGM-CSF results in a significant increase in CD4+Foxp3+ T cells in the spleen of both control and tumor-bearing mice, and that nearly half of CD4+ TIL expressed this marker. In addition, CD4+ TIL cells were of an activated/memory (ICOS(high)CD62L(low)CD45RB(low)) phenotype and were capable of suppressing allospecific T cell proliferation and IFN-gamma production from (in vivo cross-primed) anti-CMS4 CD8+ T cells in vitro, via a mechanism at least partially dependent on IL-10 and TGF-beta. Importantly, in vivo depletion of CD4+ T cells resulted in the ability of previously ineffective, rFL plus rGM-CSF therapy-induced CD8+ T cells to now mediate tumor regression.     

Viral diversity and diversification of major non-structural genes vif, vpr, vpu, tat exon 1 and rev exon 1 during primary HIV-1 subtype C infection

To assess the level of intra-patient diversity and evolution of HIV-1C non-structural genes in primary infection, viral quasispecies obtained by single genome amplification (SGA) at multiple sampling timepoints up to 500 days post-seroconversion (p/s) were analyzed. The mean intra-patient diversity was 0.11% (95% CI; 0.02 to 0.20) for vif, 0.23% (95% CI; 0.08 to 0.38) for vpr, 0.35% (95% CI; -0.05 to 0.75) for vpu, 0.18% (95% CI; 0.01 to 0.35) for tat exon 1 and 0.30% (95% CI; 0.02 to 0.58) for rev exon 1 during the time period 0 to 90 days p/s. The intra-patient diversity increased gradually in all non-structural genes over the first year of HIV-1 infection, which was evident from the vif mean intra-patient diversity of 0.46% (95% CI; 0.28 to 0.64), vpr 0.44% (95% CI; 0.24 to 0.64), vpu 0.84% (95% CI; 0.55 to 1.13), tat exon 1 0.35% (95% CI; 0.14 to 0.56 ) and rev exon 1 0.42% (95% CI; 0.18 to 0.66) during the time period of 181 to 500 days p/s. There was a statistically significant increase in viral diversity for vif (p = 0.013) and vpu (p = 0.002). No associations between levels of viral diversity within the non-structural genes and HIV-1 RNA load during primary infection were found. The study details the dynamics of the non-structural viral genes during the early stages of HIV-1C infection.     

Production of alkaline protease by an alkaliphilic bacteria isolated from an alkaline soda lake

A new alkaliphilic strain of Microbacterium producing an alkaline protease was isolated from an alkaline soda lake in Ethiopia. High level of protease activity was produced in the presence of glucose and sucrose as carbon sources. The optimum temperature and pH for activity were 65°C and 9.5-11.5 respectively. Above 50°C, Ca²⁺ was required for enzyme activity and stability. At 55 and 60°C it retained 100 and 85% of its original activity respectively after 1 h incubation. The enzyme was stable over the pH range of 5-12. This revised version was published online in November 2006 with corrections to the Cover Date.     

Modulation of Anopheles gambiae Epsilon glutathione transferase activity by plant natural products in vitro

Elevated glutathione transferase (GST) E2 activity is associated with DDT resistance in the mosquito Anopheles gambiae. The search for chemomodulators that inhibit the function of AgGSTE2 would enhance the insecticidal activity of DDT. Therefore, we examined the interaction of novel natural plant products with heterologously expressed An. gambiae GSTE 2 in vitro. Five of the ten compounds, epiphyllocoumarin (Tral-1), knipholone anthrone, isofuranonaphthoquinones (Mr 13/2, Mr13/4) and the polyprenylated benzophenone (GG1) were shown to be potent inhibitors of AgGSTE2 with IC(50) values of 1.5 microM, 3.5 microM, 4 microM, 4.3 microM and 4.8 microM respectively. Non-competitive inhibition was obtained for Tral 1 and GG1 with regards to GSH (K(i) of 0.24 microM and 0.14 microM respectively). Competitive inhibition for Tral1 was obtained with CDNB (K(i) = 0.4 microM) whilst GG1 produced mixed type of inhibition. The K(i) and K(i)' for GSH for Tral-1 and GG1 were 0.2 microM and 0.1 microM respectively. These results suggest that the novel natural plant products, particularly Tral-1, represent potent AgGSTE2 in vitro inhibitors.     

Prevalence of Intestinal Parasitic Infections among Children under Five Years of Age with Emphasis on Schistosoma mansoni in Wonji Shoa Sugar Estate,Ethiopia

Intestinal parasite infections are major public health problems of children in developing countries causing undernutrition, anemia, intestinal obstruction and mental and physical growth retardation. This study was conducted to assess the prevalence of intestinal helminthic infections among children under five years of age with emphasis on Schistosoma mansoni in Wonji Shoa Sugar Estate, Ethiopia. A cross-sectional parasitological survey was conducted in under-five children living in Wonji Shoa Sugar Estate Ethiopia, April, 2013. Stool samples were collected and examined for intestinal parasites using single Kato-Katz and single Sodium acetate-acetic acid-formalin (SAF) solution concentration methods. Out of 374 children examined using single Kato-Katz and single SAF-concentration methods, 24.3% were infected with at least one intestinal parasite species. About 10.4%, 8.8%, 4.6%, 2.9%, 1.6% and 0.8% of the children were infected with Hymenolepis nana, Schistosoma mansoni, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis and hookworm, respectively. Prevalence of double, triple and quadruple intestinal helminthic infection was 6.4%, 0.54% and 1.1%, respectively. A significant increase in prevalence of S. mansoni (8.3% versus 3.2%) and T. trichiura (2.7% versus 0.5%) infection was observed when determined via the single Kato-Katz method compared to the prevalence of the parasites determined via the single SAF-concentration method. On the other hand, the single SAF-concentration method (9.1%) revealed a significantly higher prevalence of H. nana infection than the single Kato-Katz (1.6%) does. In conclusion, intestinal helminths infections particularly S. mansoni and H. nana were prevalent in under-five children of Wonji Shoa Sugar Estate. Including praziquantel treatment in the deworming program as per the World Health Organization guidelines would be vital to reduce the burden of these diseases in areas where S. mansoni and H. nana infections are prevalent among under-fives. Kato-Katz can be used in estimating the prevalence of S. mansoni and other helminth infections.