Macrophage-mediated angiogenic activation of outgrowth endothelial cells in co-culture with primary osteoblasts.

The successful vascularisation of complex tissue engineered constructs for bone regeneration is still a major challenge in the field of tissue engineering. In this context, co-culture systems of endothelial cells and osteoblasts represent a promising approach to advance the formation of a stable vasculature as well as an excellent in vitro model to identify factors that positively influence bone healing processes, including angiogenesis. Under physiological conditions, the activation phase of angiogenesis is mainly induced by hypoxia or inflammation. Inflammatory cells such as macrophages secrete proinflammatory cytokines and proangiogenic growth factors, finally leading to the formation of new blood vessels. The aim of this study was to investigate if macrophages might positively influence the formation of microvessel-like structures via inflammatory mechanisms in a co-culture system consisting of human outgrowth endothelial cells (OECs) and primary osteoblasts. Treatment of co-cultures with macrophages (induced from THP-1) resulted in a higher number of microvessel-like structures formed by OECs compared to the co-culture. This change correlated with a significantly higher concentration of the proangiogenic VEGF in cell culture supernatants of triple-cultures and was accompanied by an increase in the expression of different proinflammatory cytokines, such as IL-6, IL-8 and TNFα. In addition, the expression of E-selectin and ICAM-1, adhesion molecules which are strongly involved in the interaction between leukocytes and endothelial cells during the process of inflammation was also found to be higher in triple-cultures compared to the double co-cultures, documenting an ongoing proinflammatory stimulus. These results raise the possibility of actively using pro-inflammatory stimuli in a tissue engineering context to accelerate healing mechanisms.

A diverse range of Phytophthora species from botanical gardens in South Africa, including the novel Clade 5 species, Phytophthora mammiformis sp. nov.

The genus Phytophthora contains many destructive and globally important plant pathogens. In the last decade, targeted sampling efforts have resulted in a dramatic increase in the number of known species, as well as a better understanding of their global distribution. Routine activities undertaken in botanical gardens, combined with great numbers of local and international visitors, place botanical gardens at risk to the accidental introduction and establishment of pathogens such as Phytophthora spp. In this study, the occurrence of Phytophthora was investigated in two botanical gardens in the KwaZulu-Natal Province of South Africa. Symptomatic collar and stem tissues were collected, and root and rhizosphere soil samples were taken from trees exhibiting symptoms of decline. Standard baiting techniques and direct plating of symptomatic tissues revealed the presence of seven species of Phytophthora residing in four phylogenetic clades. Five of these species, P. cinnamomi, P. citrophthora, P. multivora, P. parvispora and the informally designated taxon Phytophthora sp. stellaris were known to be present in South Africa and P. aquimorbida was recorded for the first time. Of these, P. citrophthora represented a novel host-pathogen association causing bleeding cankers on indigenous Celtis africana. A multilocus phylogenetic analysis based on ITS, ßtub, cox1 and hsp90 sequences showed the presence of an undescribed species belonging to the Phytophthora ITS Clade 5. This species is described here as Phytophthora mammiformis sp. nov. This study highlights the importance of monitoring botanical gardens for the detection and discovery of pathogens and emphasises their value as sites for the discovery of novel host-pathogen associations. Citation: Paap T, Balocchi F, Burgess TI, Bose T, Wingfield MJ (2024). A diverse range of Phytophthora species from botanical gardens in South Africa, including the novel Clade 5 species, Phytophthora mammiformis sp. nov. Fungal Systematics and Evolution 13: 111-122. doi: 10.3114/fuse.2024.13.05.

Tissue ontogeny and chemical composition influence bacterial biodiversity in the wood and shoot tip of Populus nigra.

Plant-microbe interactions significantly influence plant growth dynamics and adaptability. This study explores the impact of metabolites on microbial biodiversity in shoot tips and wood of Populus nigra under greenhouse conditions, using high-throughput sequencing and metabolite profiling. Branches from P. nigra were harvested, rooted, and transplanted into pots for growth. After 3 months, tissue samples from shoot tips and wood were collected, and metabolites extracted and analysed using GC-MS and LC-MS. Genomic DNA was extracted and subjected to high-throughput sequencing for bacterial biodiversity profiling. Both datasets were analysed using bioinformatic and statistical pipelines. Metabolite profiling indicated that shoot tips had a higher relative abundance of primary and secondary metabolites, including sugars, fatty acids, organic acids, phenolic acid derivatives and salicinoids, while wood was enriched in flavonoids. Bacterial biodiversity also differed significantly between these tissues, with Clostridiales, Bacteroidales and Bacillales dominating in shoot tips, associated with rapid growth and anaerobic fermentation, while wood tissues were characterized by diazotrophs from Rhizobiales, Sphingomonadales and Frankiales. PCoA clustering confirmed tissue-specific microbial differences. Functional analysis revealed an enrichment of fundamental cellular processes in shoot tips, while wood exhibited pathways related to degradation and mortality. Metabolite profiling revealed significant variations in primary and secondary metabolites, highlighting their influence on microbial biodiversity across plant tissues. The dominance of specific bacterial orders and distinct functional pathways in each tissue suggests a tailored microbial response to the unique environments of shoot tips and wood.

Measurement of the semileptonic charge asymmetry using B(s)(0) → D(s)µX decays.

We present a measurement of the time-integrated flavor-specific semileptonic charge asymmetry in the decays of B(s)(0) mesons that have undergone flavor mixing, a(sl)(s), using B(s)(0)(B(s)(0)) → D(s)(-/+) µ(±) X decays, with D(s)(-/+) → [symbol: see text]π(-/+) and [symbol: see text]→ K(+) K(-), using 10.4 fb(-1) of proton-antiproton collisions collected by the D0 detector during Run II at the Fermilab Tevatron Collider. A fit to the difference between the time-integrated D(s)(-) and D(s)(+) mass distributions of the B(s)(0) and B(s)(0) candidates yields the flavor-specific asymmetry a(sl)(s) = [-1.12 ± 0.74(stat) ± 0.17(syst)]%, which is the most precise measurement and in agreement with the standard model prediction.

Search for universal extra dimensions in pp collisions.

We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb(-1), collected by the D0 detector at a pp center-of-mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R(-1)>260 GeV in a minimal UED model.

Measurement of the W boson mass with the D0 detector.

We present a measurement of the W boson mass using data corresponding to 4.3 fb(-1) of integrated luminosity collected with the D0 detector during Run II at the Fermilab Tevatron pp collider. With a sample of 1,677,394 W → eν candidate events, we measure M(W) = 80.367 ± 0.026 GeV. This result is combined with an earlier D0 result determined using an independent Run II data sample, corresponding to 1 fb(-1) of integrated luminosity, to yield M(W) = 80.375 ± 0.023 GeV.

Measurements of WW and WZ production in W + jets final states in pp collisions.

We study WW and WZ production with ℓνqq (ℓ=e,µ) final states using data collected by the D0 detector at the Fermilab Tevatron Collider corresponding to 4.3 fb(-1) of integrated luminosity from pp collisions at sqrt[s]=1.96 TeV. Assuming the ratio between the production cross sections σ(WW) and σ(WZ) as predicted by the standard model, we measure the total WV (V=W,Z) cross section to be σ(WV)=19.6(-3.0)(+3.2) pb and reject the background-only hypothesis at a level of 7.9 standard deviations. We also use b-jet discrimination to separate the WZ component from the dominant WW component. Simultaneously fitting WW and WZ contributions, we measure σ(WW)=15.9(-3.2)(+3.7) pb and σ(WZ)=3.3(-3.3)(+4.1) pb, which is consistent with the standard model predictions.

Evidence for spin correlation in t Ì t production.

We present a measurement of the ratio of events with correlated t and t ̅t spins to the total number of t ̅t events. This ratio f is evaluated using a matrix-element-based approach in 729 t ̅t candidate events with a single lepton ℓ (electron or muon) and at least four jets. The analyzed p ̅p collisions data correspond to an integrated luminosity of 5.3 fb(-1) and were collected with the D0 detector at the Fermilab Tevatron collider operating at a center-of-mass energy √s=1.96 TeV. Combining this result with a recent measurement of f in dileptonic final states, we find f in agreement with the standard model. In addition, the combination provides evidence for the presence of spin correlation in t ̅t events with a significance of more than 3 standard deviations.

Search for violation of Lorentz invariance in top quark pair production and decay.

Using data collected with the D0 detector at the Fermilab Tevatron Collider, corresponding to 5.3 fb(-1) of integrated luminosity, we search for violation of Lorentz invariance by examining the tt[over ¯] production cross section in lepton+jets final states. We quantify this violation using the standard-model extension framework, which predicts a dependence of the tt[over ¯] production cross section on sidereal time as the orientation of the detector changes with the rotation of the Earth. Within this framework, we measure components of the matrices (c(Q))(µν33) and (c(U))(µν33) containing coefficients used to parametrize violation of Lorentz invariance in the top quark sector. Within uncertainties, these coefficients are found to be consistent with zero.

Search for the standard model Higgs boson in ZH→ℓ(+)ℓ(-)bb production with the D0 detector in 9.7 fb(-1) of pp collisions at √s = 1.96 TeV.

We present a search for the standard model (SM) Higgs boson produced in association with a Z boson in 9.7 fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider at √s = 1.96 TeV. Selected events contain one reconstructed Z→e(+)e(-) or Z→µ(+)µ(-) candidate and at least two jets, including at least one jet identified as likely to contain a b quark. To validate the search procedure, we also measure the cross section for ZZ production in the same final state. It is found to be consistent with its SM prediction. We set upper limits on the ZH production cross section times branching ratio for H→bb at the 95% C.L. for Higgs boson masses 90 ≤ M(H) ≤ 150 GeV. The observed (expected) limit for M(H) = 125 GeV is 7.1 (5.1) times the SM cross section.

Search for the standard model Higgs boson in associated WH production in 9.7 fb(-1) of pp collisions with the D0 detector.

We present a search for the standard model Higgs boson in final states with a charged lepton (electron or muon), missing transverse energy, and two or three jets, at least one of which is identified as a b-quark jet. The search is primarily sensitive to WH→ℓνbb production and uses data corresponding to 9.7 fb(-1) of integrated luminosity collected with the D0 detector at the Fermilab Tevatron pp Collider at √s = 1.96 TeV. We observe agreement between the data and the expected background. For a Higgs boson mass of 125 GeV, we set a 95% C.L. upper limit on the production of a standard model Higgs boson of 5.2 × σ(SM), where σ(SM) is the standard model Higgs boson production cross section, while the expected limit is 4.7 × σ(SM).

Combined search for the standard model Higgs boson decaying to bb using the D0 run II data set.

We present the results of the combination of searches for the standard model Higgs boson produced in association with a W or Z boson and decaying into bb using the data sample collected with the D0 detector in pp collisions at √s = 1.96 TeV at the Fermilab Tevatron Collider. We derive 95% C.L. upper limits on the Higgs boson cross section relative to the standard model prediction in the mass range 100 GeV ≤ M(H) ≤ 150 GeV, and we exclude Higgs bosons with masses smaller than 102 GeV at the 95% C.L. In the mass range 120 GeV ≤ M(H) ≤145 GeV, the data exhibit an excess above the background prediction with a global significance of 1.5 standard deviations, consistent with the expectation in the presence of a standard model Higgs boson.

Melanodevriesia, a new genus of endolichenic oleaginous black yeast recovered from the Inner Mongolia Region of China.

Black yeasts are a phylogenetically diverse group of ascomycetous fungi that may exist in both unicellular and mycelial morphs. This group of fungi contains numerous commercially significant species as well as others whose precise roles are unknown, such as endolichenic species. There is currently a paucity of data about endolichenic black yeast species. To bridge this gap, we surveyed China's Inner Mongolia Autonomous Region in July 2019. Several fungal species associated with diverse lichens were isolated during this survey. Among these were two isolates of a previously unknown species of oleaginous black yeast from Mycosphaerellales. Analyses of morphological and molecular data revealed that these two isolates were closely related to Xenodevriesia strelitziicola (Xenodevriesiaceae), although with significant differences. As a result, we established the genus Melanodevriesia gen. nov. to describe this previously unknown species, Melanodevriesia melanelixiae sp. nov. In addition, we used Transmission Electron Microscopy to visualise the intracellular oil bodies metabolised by this fungus in its unicellular state. The black yeast species identified in this study may have a wide range of commercial applications. More research is needed to determine the chemical composition of the microbial oil synthesized by this fungus and whether it has commercial value. Citation: Chang R, Cao W, Wang Y, Li S, Li X, Bose T, Si HL (2022). Melanodevriesia, a new genus of endolichenic oleaginous black yeast recovered from the Inner Mongolia Region of China. Fungal Systematics and Evolution 9: 1-9. doi: 10.3114/fuse.2022.09.01.

A precision measurement of the mass of the top quark.

The standard model of particle physics contains parameters--such as particle masses--whose origins are still unknown and which cannot be predicted, but whose values are constrained through their interactions. In particular, the masses of the top quark (M(t)) and W boson (M(W)) constrain the mass of the long-hypothesized, but thus far not observed, Higgs boson. A precise measurement of M(t) can therefore indicate where to look for the Higgs, and indeed whether the hypothesis of a standard model Higgs is consistent with experimental data. As top quarks are produced in pairs and decay in only about 10(-24) s into various final states, reconstructing their masses from their decay products is very challenging. Here we report a technique that extracts more information from each top-quark event and yields a greatly improved precision (of +/- 5.3 GeV/c2) when compared to previous measurements. When our new result is combined with our published measurement in a complementary decay mode and with the only other measurements available, the new world average for M(t) becomes 178.0 +/- 4.3 GeV/c2. As a result, the most likely Higgs mass increases from the experimentally excluded value of 96 to 117 GeV/c2, which is beyond current experimental sensitivity. The upper limit on the Higgs mass at the 95% confidence level is raised from 219 to 251 GeV/c2.

Role of ion channels in regulating Ca²âº homeostasis during the interplay between immune and cancer cells.

Ion channels are abundantly expressed in both excitable and non-excitable cells, thereby regulating the Ca(2+) influx and downstream signaling pathways of physiological processes. The immune system is specialized in the process of cancer cell recognition and elimination, and is regulated by different ion channels. In comparison with the immune cells, ion channels behave differently in cancer cells by making the tumor cells more hyperpolarized and influence cancer cell proliferation and metastasis. Therefore, ion channels comprise an important therapeutic target in anti-cancer treatment. In this review, we discuss the implication of ion channels in regulation of Ca(2+) homeostasis during the crosstalk between immune and cancer cell as well as their role in cancer progression.

Increased plasma lipid peroxidation in riboflavin-deficient, malaria-infected children.

Plasma lipid peroxides were measured as malonyldialdehyde (MDA) by the thiobarbituric acid (TBA) method in 75 children suffering from Plasmodium falciparum malaria. Their riboflavin status was assessed by measuring erythrocyte glutathione reductase activation coefficients (EGRACs), and values greater than 1.40 were regarded as indicating biochemical deficiency. Plasma MDA was higher (p less than 0.001) in patients than in control subjects; the concentrations were 3.65 +/- 0.70 and 1.77 +/- 0.45 mumol/L (means +/- SD), respectively. The riboflavin-deficient group had higher plasma MDA values (3.98 +/- 0.70 mumol/L) than did the nondeficient group (3.30 +/- 0.68 mumol/L, p less than 0.001). Plasma MDA concentrations correlated with EGRACs (r = 0.46, p less than 0.01) in the patients. It is proposed that riboflavin deficiency restricts regeneration of reduced glutathione making the parasitized erythrocytes more vulnerable to destructive lipid peroxidation and increasing plasma lipid hydroperoxides.

Plasma antioxidants and lipid peroxidation products in falciparum malaria.

To investigate the influence of Plasmodium falciparum malaria on plasma antioxidants and lipid peroxidation, plasma ascorbate, urate, total protein and albumin, ceruloplasmin and malondialdehyde (MDA) were determined in two groups of 42 patients each, one with mild and the other with severe falciparum malaria, and in an equal number of age- and sex-matched control subjects. Plasma MDA was found to be significantly higher in malaria patients, and the increase was proportional to the severity of the disease. Of the antioxidants, ascorbate and albumin decreased with severity of disease while urate and ceruloplasmin increased. Only ascorbate correlated inversely with MDA both in mild (r = -0.341, P < 0.05) and severe malaria (r = 0.545, P < 0.01). While plasma albumin correlated inversely (r = -0.442, P < 0.01), urate and ceruloplasmin correlated directly (r = 0.419, P < 0.01 and r = 0.349, P < 0.05, respectively) only in patients with severe malaria. These antioxidants also correlated well with markers of disease severity, indicating the influence of disease severity in regulating their levels in plasma. The presence of significant quantities of ascorbate and albumin, along with increases in some of the other antioxidants and MDA, indicates ineffectiveness of the antioxidant defense system in controlling plasma lipid peroxide content. Increased amounts of thiobarbituric acid-reactive material could have been the result of spillover from increased tissue peroxidation or the presence of pro-oxidants in malarial plasma.

Increased cerebrospinal fluid protein and lipid peroxidation products in patients with cerebral malaria.

Membrane lipid peroxidation by reactive oxygen species leading to increased capillary permeability is considered an important event in the pathogenesis of severe malaria. A significant decrease in plasma albumin and increases in cerebrospinal fluid (CSF) protein and malondialdehyde (MDA) were observed in 73 patients with cerebral malaria, compared to values in 23 control patients. The greatest effect was noticed in the most severely ill patients. The ratio of CSF protein to plasma albumin was increased in the patients compared to the controls, and in fatal cases of cerebral malaria compared to non-fatal cases. Brain necropsies showed oedema, fibrin deposits and mononuclear cell infiltration. It is proposed that cerebral oedema due to enhanced permeability of vascular endothelium induced by increased lipid peroxidation plays a crucial role in the causation of cerebral malaria.

Hypoglycaemia in severe falciparum malaria.

The incidence of hypoglycaemia and the role of quinine in its causation was assessed in 46 patients with severe Plasmodium falciparum malaria. Plasma glucose and immunoreactive insulin were estimated before, during and after quinine therapy. In 5 patients the plasma glucose was in the hypoglycaemic range, the lowest value being 0.67 mmol/litre (12 mg/dl) in a pregnant patient. Most of the remaining patients showed a significant fall in plasma glucose (P less than 0.05), but not to the hypoglycaemic range, and an increase in plasma insulin after quinine (P less than 0.01). A good correlation was found between these changes (r = 0.79, P less than 0.01). Patients with severe P. falciparum malaria, particularly those on quinine therapy, should be watched carefully for developing hypoglycaemia.

Riboflavin deficiency and severity of malaria.

The riboflavin status of 64 children suffering from malarial infection was assessed by measuring the activation coefficient of erythrocyte glutathione reductase. Thirty-five children were found to be deficient in riboflavin whereas in 29 children riboflavin status was within the normal range. The median parasite count and its range on admission in the deficient group (2.7 per cent, range 0.3-13.6) was lower than that in the non-deficient group (5.3 per cent, range 0.6-30.2). The correlation between activity coefficient and parasite count was significant (R = -0.49). The recovery process was slower in the deficient group even though they had a relatively lower parasite count. It is inferred that riboflavin deficiency leads to inhibition of growth and multiplication of plasmodia. Its beneficial effects in malaria infection needs further evaluation.