Effluent solids recirculation to municipal sludge digesters enhances long-chain fatty acids degradation capacity.

BACKGROUND: Slow degradation kinetics of long-chain fatty acids (LCFA) and their accumulation in anaerobic digesters disrupt methanogenic activity and biogas production at high loads of waste lipids. In this study, we evaluated the effect of effluent solids recirculation on microbial LCFA (oleate) degradation capacity in continuous stirred-tank sludge digesters, with the overall aim of providing operating conditions for efficient co-digestion of waste lipids. Furthermore, the impacts of LCFA feeding frequency and sulfide on process performance and microbial community dynamics were investigated, as parameters that were previously shown to be influential on LCFA conversion to biogas. RESULTS: Effluent solids recirculation to municipal sludge digesters enabled biogas production of up to 78% of the theoretical potential from 1.0 g oleate l-1 day-1. In digesters without effluent recirculation, comparable conversion efficiency could only be reached at oleate loading rates up to 0.5 g l-1 day-1. Pulse feeding of oleate (supplementation of 2.0 g oleate l-1 every second day instead of 1.0 g oleate l-1 every day) did not have a substantial impact on the degree of oleate conversion to biogas in the digesters that operated with effluent recirculation, while it marginally enhanced oleate conversion to biogas in the digesters without effluent recirculation. Next-generation sequencing of 16S rRNA gene amplicons of bacteria and archaea revealed that pulse feeding resulted in prevalence of fatty acid-degrading Smithella when effluent recirculation was applied, whereas Candidatus Cloacimonas prevailed after pulse feeding of oleate in the digesters without effluent recirculation. Combined oleate pulse feeding and elevated sulfide level contributed to increased relative abundance of LCFA-degrading Syntrophomonas and enhanced conversion efficiency of oleate, but only in the digesters without effluent recirculation. CONCLUSIONS: Effluent solids recirculation improves microbial LCFA degradation capacity, providing possibilities for co-digestion of larger amounts of waste lipids with municipal sludge.

The YIN and YANG of lipoproteins in developing and preventing infectious arthritis by Staphylococcus aureus.

Rapid bone destruction often leads to permanent joint dysfunction in patients with septic arthritis, which is mainly caused by Staphylococcus aureus (S. aureus). Staphylococcal cell wall components are known to induce joint inflammation and bone destruction. Here, we show that a single intra-articular injection of S. aureus lipoproteins (Lpps) into mouse knee joints induced chronic destructive macroscopic arthritis through TLR2. Arthritis was characterized by rapid infiltration of neutrophils and monocytes. The arthritogenic effect was mediated mainly by macrophages/monocytes and partially via TNF-α but not by neutrophils. Surprisingly, a S. aureus mutant lacking Lpp diacylglyceryl transferase (lgt) caused more severe joint inflammation, which coincided with higher bacterial loads of the lgt mutant in local joints than those of its parental strain. Coinjection of pathogenic S. aureus LS-1 with staphylococcal Lpps into mouse knee joints caused improved bacterial elimination and diminished bone erosion. The protective effect of the Lpps was mediated by their lipid moiety and was fully dependent on TLR2 and neutrophils. The blocking of CXCR2 on neutrophils resulted in total abrogation of the protective effect of the Lpps. Our data demonstrate that S. aureus Lpps elicit innate immune responses, resulting in a double-edged effect. On the one hand, staphylococcal Lpps boost septic arthritis. On the other hand, Lpps act as adjuvants and activate innate immunity, which could be useful for combating infections with multiple drug-resistant strains.

Mental reinstatement of encoding context improves episodic remembering.

This study investigates context-dependent memory retrieval. Previous work has shown that physically re-experiencing the encoding context at retrieval improves memory accessibility. The current study examined if mental reconstruction of the original encoding context would yield parallel memory benefits. Participants performed a cued-recall memory task, preceded either by a mental or by a physical context reinstatement task, and we manipulated whether the context reinstated at retrieval overlapped with the context of the target episode. Both behavioral and electrophysiological measures of brain activity showed strong encoding-retrieval (E-R) overlap effects, with facilitated episodic retrieval when the encoding and retrieval contexts overlapped. The electrophysiological E-R overlap effect was more sustained and involved more posterior regions when context was mentally compared with physically reinstated. Additionally, a time-frequency analysis revealed that context reinstatement alone engenders recollection of the target episode. However, while recollection of the target memory is readily prompted by a physical reinstatement, target recollection during mental reinstatement is delayed and depends on the gradual reconstruction of the context. Taken together, our results show facilitated episodic remembering also when mentally reinstating the encoding context; and that such benefits are supported by both shared and partially non-overlapping neural mechanisms when the encoding context is mentally reconstructed as compared with physically presented at the time of retrieval.

Tanshinone IIA enhances bystander cell killing of cancer cells expressing Drosophila melanogaster deoxyribonucleoside kinase in nuclei and mitochondria.

Heterologous expression of the Drosophila melanogaster multi-substrate deoxyribonucleoside kinase (Dm-dNK) increases the sensitivity of cancer cells to several cytotoxic nucleoside analogs. Thus, it may be used as a suicide gene in combined gene/chemotherapy treatment of cancer. To further characterize this potential suicide gene, we constructed two retroviral vectors that enabled the expression of Dm-dNK in cancer cells. One vector harbored the wild­type enzyme that localized to the nucleus. The other vector harbored a mitochondrial localized mutant enzyme that was constructed by deleting the nuclear localization signal and fusing it to a mitochondrial import signal of cytochrome c oxidase. A thymidine kinase-deficient osteosarcoma cell line was transduced with the recombinant viruses. The sensitivity and bystander cell killing in the presence of pyrimidine nucleoside analogs (E)-5-(2-bromovinyl)­2'­deoxyuridine and 1-ß-D-arabinofuranosylthymine were investigated. Tanshinone IIA is a constituent of Danshen; a traditional Chinese medicine used in the treatment of cardiovascular diseases. This study also looked at the influence of Tanshinone IIA on the bystander effect and the underlying mechanisms. We showed that sensitivity of the osteosarcoma cell line to the nucleoside analogs and the efficiency of bystander cell killing were independent of the subcellular localization of Dm-dNK. The enhanced effect of tanshinone IIA on the bystander effect was related to the increased expression of Cx43 and Cx26.

The Sweden Cancerome Analysis Network - Breast (SCAN-B) Initiative: a large-scale multicenter infrastructure towards implementation of breast cancer genomic analyses in the clinical routine.

BACKGROUND: Breast cancer exhibits significant molecular, pathological, and clinical heterogeneity. Current clinicopathological evaluation is imperfect for predicting outcome, which results in overtreatment for many patients, and for others, leads to death from recurrent disease. Therefore, additional criteria are needed to better personalize care and maximize treatment effectiveness and survival. METHODS: To address these challenges, the Sweden Cancerome Analysis Network - Breast (SCAN-B) consortium was initiated in 2010 as a multicenter prospective study with longsighted aims to analyze breast cancers with next-generation genomic technologies for translational research in a population-based manner and integrated with healthcare; decipher fundamental tumor biology from these analyses; utilize genomic data to develop and validate new clinically-actionable biomarker assays; and establish real-time clinical implementation of molecular diagnostic, prognostic, and predictive tests. In the first phase, we focus on molecular profiling by next-generation RNA-sequencing on the Illumina platform. RESULTS: In the first 3 years from 30 August 2010 through 31 August 2013, we have consented and enrolled 3,979 patients with primary breast cancer at the seven hospital sites in South Sweden, representing approximately 85% of eligible patients in the catchment area. Preoperative blood samples have been collected for 3,942 (99%) patients and primary tumor specimens collected for 2,929 (74%) patients. Herein we describe the study infrastructure and protocols and present initial proof of concept results from prospective RNA sequencing including tumor molecular subtyping and detection of driver gene mutations. Prospective patient enrollment is ongoing. CONCLUSIONS: We demonstrate that large-scale population-based collection and RNA-sequencing analysis of breast cancer is feasible. The SCAN-B Initiative should significantly reduce the time to discovery, validation, and clinical implementation of novel molecular diagnostic and predictive tests. We welcome the participation of additional comprehensive cancer treatment centers. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02306096.

Ethnobotanical study of nutri-medicinal plants used for the management of HIV/AIDS opportunistic ailments among the local communities of western Uganda.

ETHNOPHARMACOLOGICAL RELEVANCE: Herbal remedies are a source of therapeutics for nearly 80% of the population in Uganda. Poor health facilities and limited access to antiretroviral drugs have perpetuated and increased the use of traditional medicine especially in rural areas for the treatment of opportunistic ailments of HIV/AIDS. To document the traditional uses of nutri-medicinal plants in the management of immunocompromised ailments associated with HIV/AIDS. To document the parts and growth forms of plants used, methods of preparation and administration of the herbal remedies. MATERIALS AND METHODS: The study was conducted in Mbarara and Isingiro districts of western Uganda between December 2010 and May 2011. Ethnobotanical information was collected from 64 respondents who were sampled based on recommendations of local elders and administrators. Ethnobotanical data on the use of nutri-medicinal plants for traditional treatment of HIV/AIDS opportunistic ailments were collected by employing semi-structured interviews with selected respondents, house hold visits and field observations as described by (Martin, 1995a). The respondents were mainly traditional medical practitioners who treat patients who are already receiving antiretroviral drugs. Fidelity levels of plant species and informant consensus factor were determined to show the percentage of informants claiming the use of certain plant species for the same major purpose and to analyse people's knowledge of plant use. RESULTS: The study revealed 81 plant species most of which were herbs (49%). Leaves (71%) were the most frequently used parts in remedy preparations which were mainly administered orally (85%). The majority of plants (54%) were harvested from wild populations. Hibiscus sabdariffa L., Plumeria obtusa L., and Abutilon guineense (Shumach.) Baker. F and Exell were the nutri-medicinal plants that scored the highest Fidelity level values. The informant's consensus about usages of plants ranged from 0.75 to 0.80. Plants that are presumed to be effective in treating a certain disease have higher informant consensus factor (ICF) values. Family Asteraceae accounted for 18% of the total species recorded. Thirteen species (16%) of the plants are edible and provide nutritional support. CONCLUSION: The study recorded plant species with potential to treat ailments associated with immunocompromised people living with HIV/AIDS in western Uganda. Such studies can help stimulate confidence in traditional medicine and enhance appreciation of herbal medicine among the people and to appreciate the value of the plant resources and therefore enhance conservation efforts of the plant species. The high consensus means the majority of informants agree on the use of plant species and this reflects the intercultural relevance and the agreement in the use of the nutri-medicinal plants to the people. We recommend the documented plants for further Ethnopharmacological studies.

Role of 2-methoxyestradiol as inhibitor of arthritis and osteoporosis in a model of postmenopausal rheumatoid arthritis.

In postmenopausal rheumatoid arthritis, both the inflammatory disease and estrogen deficiency contribute to the development of osteoporosis. As hormone replacement therapy is no longer an option, we hypothesized that 2-methoxyestradiol (2me2) could be beneficial, and asked if such therapy was associated with effects on reproductive organs. Mice were ovariectomized and arthritis was induced, whereafter mice were administered 2me2, estradiol, or placebo. Clinical and histological scores of arthritis, together with bone mineral density were evaluated. Uteri weight, reactive oxygen species (ROS) from spleen cells, and characterization of cells from joints and lymph nodes were analyzed. In addition, in vivo activation of estrogen response elements (ERE) by 2me2 was evaluated. Treatment with 2me2 and estradiol decreased the frequency and severity of arthritis and preserved bone. Joint destruction was reduced, neutrophils diminished and ROS production decreased. The uterine weight increased upon long-term 2me2 exposure, however short-term exposure did not activate ERE in vivo.

Retained sensitivity to cytotoxic pyrimidine nucleoside analogs in thymidine kinase 2 deficient human fibroblasts.

Thymidine kinase 2 (TK2) is a mitochondrial deoxyribonucleoside kinase that phosphorylates several nucleoside analogs used in anti-viral and anti-cancer therapy. A fibroblast cell line with decreased TK2 activity was investigated in order to obtain insights in the effects of TK2 deficiency on nucleotide metabolism. The role of TK2 for the sensitivity against cytotoxic nucleoside analogs was also investigated. The TK2 deficient cells retained their sensitivity against all pyrimidine nucleoside analogs tested. This study suggests that nucleoside analog phosphorylation mediated by TK2 may be less important, compared to other deoxyribonucleoside kinases, for the cytotoxic effects of these compounds.

Uric acid, a nucleic acid degradation product, down-regulates dsRNA-triggered arthritis.

Uric acid, the naturally occurring degradation product of purine metabolism, is a danger signal, driving maturation of dendritic cells. It is well known that uric acid crystals display potent proinflammatory properties--the cause of gout--whereas the biological properties of soluble uric acid are less well documented. We have demonstrated previously that nucleic acids of endogenous and exogenous origin display proinflammatory properties. The aim of the present study was to assess the impact of soluble uric acid on in vivo inflammatory responses. Mice were administered with uric acid suspension in saline or saline alone prior to induction of neutrophil-mediated inflammation, delayed-type hypersensitivity, histamin-induced edema (measure of vasodilation capacity), as well as double-stranded (ds)RNA-triggered arthritis. Frequency and severity of arthritis were decreased significantly in mice exposed to dsRNA and simultaneously treated with uric acid as compared with saline-treated controls. Also, granulocyte-mediated inflammatory response and vasodilation capacity were reduced significantly in mice treated with uric acid as compared with their control group. The data suggest that down-regulation of inflammation was mediated by skewing the inflammatory response from the peripheral sites to the peritoneal cavity and down-regulating vasodilatatory capacity and thereby affecting leukocyte migration. In contrast, the T cell-mediated delayed-type hypersensitivity reaction was not affected significantly in mice exposed to uric acid. These findings demonstrate that uric acid displays a potent, distant anti-inflammatory effect in vivo. This property seems to be mediated by down-regulation of neutrophil influx to the site of inflammatory insult.

Human mitochondrial pyrophosphatase: cDNA cloning and analysis of the gene in patients with mtDNA depletion syndromes.

Pyrophosphatases (PPases) catalyze the hydrolysis of inorganic pyrophosphate generated in several cellular enzymatic reactions. A novel human pyrophosphatase cDNA encoding a 334-amino-acid protein approximately 60% identical to the previously identified human cytosolic PPase was cloned and characterized. The novel enzyme, named PPase-2, was enzymatically active and catalyzed hydrolysis of pyrophosphate at a rate similar to that of the previously identified PPase-1. A functional mitochondrial import signal sequence was identified in the N-terminus of PPase-2, which targeted the enzyme to the mitochondrial matrix. The human pyrophosphatase 2 gene (PPase-2) was mapped to chromosome 4q25 and the 1.4-kb mRNA was ubiquitously expressed in human tissues, with highest levels in muscle, liver, and kidney. The yeast homologue of the mitochondrial PPase-2 is required for mitochondrial DNA maintenance and yeast cells lacking the enzyme exhibit mitochondrial DNA depletion. We sequenced the PPA2 gene in 13 patients with mitochondrial DNA depletion syndromes (MDS) of unknown cause to determine if mutations in the PPA2 gene of these patients were associated with this disease. No pathogenic mutations were identified in the PPA2 gene of these patients and we found no evidence that PPA2 gene mutations are a common cause of MDS in humans.