Prevalence of Drug Injection, Sexual Activity, Tattooing, and Piercing Among Prison Inmates.

Prisoners engage in a range of risk behaviors that can lead to the transmission of viral infections, such as HIV, hepatitis B and hepatitis C. In this review, we summarize the epidemiologic literature from 2007 to 2017 on 4 key risk behaviors for human immunodeficiency virus and hepatitis C virus among prisoners globally: drug injection, sexual activity, tattooing, and piercing. Of 9,303 peer-reviewed and 4,150 gray literature publications, 140 and 14, respectively, met inclusion criteria covering 53 countries (28%). Regions with high levels of injection drug use were Asia Pacific (20.2%), Eastern Europe and Central Asia (17.3%), and Latin America and the Caribbean (11.3%), although the confidence interval for Latin America was high. Low levels of injection drug use in prison were found in African regions. The highest levels of sexual activity in prison were in Europe and North America (12.1%) and West and Central Africa (13.6%); low levels were reported from the Middle East and North African regions (1.5%). High levels of tattooing were reported from Europe and North America (14.7%), Asia Pacific (21.4%), and Latin America (45.4%). Prisons are burdened with a high prevalence of infectious diseases and risk behaviors for transmission of these diseases, and, commonly, a striking lack of evidence-based infection control measures, even when such measures are available in the surrounding community. Given that most prisoners return to these communities, failure to implement effective responses has repercussions not only prisoner health but also for public health.

Luminosity-independent measurement of the proton-proton total cross section at √s=8 TeV.

The TOTEM collaboration has measured the proton-proton total cross section at √s=8 TeV using a luminosity-independent method. In LHC fills with dedicated beam optics, the Roman pots have been inserted very close to the beam allowing the detection of ~90% of the nuclear elastic scattering events. Simultaneously the inelastic scattering rate has been measured by the T1 and T2 telescopes. By applying the optical theorem, the total proton-proton cross section of (101.7±2.9) mb has been determined, well in agreement with the extrapolation from lower energies. This method also allows one to derive the luminosity-independent elastic and inelastic cross sections: σ(el)=(27.1±1.4) mb; σ(inel)=(74.7±1.7) mb.

Double diffractive cross-section measurement in the forward region at the LHC.

The first double diffractive cross-section measurement in the very forward region has been carried out by the TOTEM experiment at the LHC with a center-of-mass energy of sqrt[s]=7 TeV. By utilizing the very forward TOTEM tracking detectors T1 and T2, which extend up to |η|=6.5, a clean sample of double diffractive pp events was extracted. From these events, we determined the cross section σDD=(116±25) µb for events where both diffractive systems have 4.7<|η|min<6.5.

Iron in boreal river catchments: Biogeochemical, ecological and management implications.

Iron (Fe) is an important element in aquatic ecosystems worldwide because it is intimately tied with multiple abiotic and biotic phenomena. Here, we give a survey of manifold influences of Fe, and the key factors affecting it in the boreal catchments and their waters. It includes the perspectives of biogeochemistry, hydrology, ecology, and river basin management. We emphasize views on the dynamics and impacts of different forms of Fe in riverine environments, including organic colloids and particles, as well as inorganic fractions. We also provide perspectives for land use management in boreal catchments and suggest guidelines for decision making and water management. Based on our survey, the main emphases of water protection and management programs should be (i) prevention of Fe mobilization from soil layers by avoiding unnecessary land-use activities and minimizing soil disturbance in high-risk areas; (ii) disconnecting Fe-rich ground water discharge from directly reaching watercourses; and (iii) decreasing transport of Fe to watercourses by applying efficient water pollution control approaches. These approaches may require specific methods that should be given attention depending on catchment conditions in different areas. Finally, we highlight issues requiring additional research on boreal catchments. A key issue is to increase our understanding of the role of Fe in the utilization of DOM in riverine food webs, which are typically highly heterotrophic. More knowledge is needed on the metabolic and behavioral resistance mechanisms that aquatic organisms, such as algae, invertebrates, and fish, have developed to counter the harmful impacts of Fe in rivers with naturally high Fe and DOM concentrations. It is also emphasized that to fulfil the needs presented above, as well as to develop effective methods for decreasing the harmful impacts of Fe in water management, the biogeochemical processes contributing to Fe transport from catchments via rivers to estuaries should be better understood.

Integrin alpha2beta1 mediates isoform-specific activation of p38 and upregulation of collagen gene transcription by a mechanism involving the alpha2 cytoplasmic tail.

Two collagen receptors, integrins alpha1beta1 and alpha2beta1, can regulate distinct functions in cells. Ligation of alpha1beta1, unlike alpha2beta1, has been shown to result in recruitment of Shc and activation of the Ras/ERK pathway. To identify the downstream signaling molecules activated by alpha2beta1 integrin, we have overexpressed wild-type alpha2, or chimeric alpha2 subunit with alpha1 integrin cytoplasmic domain in human osteosarcoma cells (Saos-2) lacking endogenous alpha2beta1. The chimeric alpha2/alpha1 chain formed a functional heterodimer with beta1. In contrast to alpha2/alpha1 chimera, forced expression of alpha2 integrin resulted in upregulation of alpha1 (I) collagen gene transcription in response to three-dimensional collagen, indicating that the cytoplasmic domain of alpha2 integrin was required for signaling. Furthermore, signals mediated by alpha2beta1 integrin specifically activated the p38alpha isoform, and selective p38 inhibitors blocked upregulation of collagen gene transcription. Dominant negative mutants of Cdc42, MKK3, and MKK4 prevented alpha2beta1 integrin-mediated activation of p38alpha. RhoA had also some inhibitory effect, whereas dominant negative Rac was not effective. Our findings show the isoform-specific activation of p38 by alpha2beta1 integrin ligation and identify Cdc42, MKK3, and MKK4 as possible downstream effectors. These observations reveal a novel signaling mechanism of alpha2beta1 integrin that is distinct from ones previously described for other integrins.

Catchment properties and the photosynthetic trait composition of freshwater plant communities.

Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO2 concentrations may alter the species compositions of freshwater plant communities.

Expression of integrins and basement membrane components by wound keratinocytes.

Extracellular matrix proteins and their cellular receptors, integrins, play a fundamental role in keratinocyte adhesion and migration. During wound healing, keratinocytes detach, migrate until the two epithelial sheets confront, and then regenerate the basement membrane. We examined the expression of different integrins and their putative ligands in keratinocytes during human mucosal wound healing. Migrating keratinocytes continuously expressed kalinin but not the other typical components of the basement membrane zone: type IV collagen, laminin, and type VII collagen. When the epithelial sheets confronted each other, these missing basement membrane components started to appear gradually through the entire wound area. The expression of integrin beta 1 subunit was increased in keratinocytes during migration. The beta 1-associated alpha 2 and alpha 3 subunits were expressed constantly by wound keratinocytes whereas the alpha 5 subunit was present only in keratinocytes during reepithelialization. Furthermore, migrating cells started to express alpha v-integrins which were not present in the nonaffected epithelium. All keratinocytes also expressed the alpha 6 beta 4 integrin during migration. In the migrating cells, the distribution of integrins was altered. In normal mucosa, beta 1-integrins were located mainly on the lateral plasma membrane and alpha 6 beta 4 at the basal surface of basal keratinocytes in the nonaffected tissue. In wounds, integrins were found in filopodia of migrating keratinocytes, and also surrounding cells in several cell layers of the migrating sheet. The results indicate that migrating keratinocytes, in deep human wounds enlarge their integrin repertoire. The changes in integrin expression take place concomitantly with changes in the basement membrane composition, suggesting a close interplay of these two groups of molecules during wound healing.

Control of junB and extracellular matrix protein expression by transforming growth factor-beta 1 is independent of simian virus 40 T antigen-sensitive growth-sensitive growth-inhibitory events.

Treatment of Mv1Lu mink lung epithelial cells with transforming growth factor-beta 1 (TGF-beta 1) prevents phosphorylation of the retinoblastoma susceptibility gene product, RB, in late G1 phase of the cell cycle, which is thought to retain RB in a growth-suppressive state. This effect is paralleled by cell cycle arrest in late G1 (M. Laiho, J. A. DeCapric, J. W. Ludlow, D. M. Livingston, and J. Massagué, Cell 62:175-185, 1990). Arrest can be prevented by expression of simian virus 40 T antigen, which binds to underphosphorylated RB, presumably blocking its growth-suppressive activity. The response of cells to TGF-beta 1, however, is complex and includes changes in the levels of expression of genes encoding nuclear transcription factors and extracellular matrix components. To define the relationships among various components of the TGF-beta 1 response, we have investigated the effect of TGF-beta 1 on cells whose growth-inhibitory response to this factor is prevented by T antigen. TGF-beta 1 addition to exponentially growing Mv1Lu cells increased the levels of junB mRNA and of three extracellular matrix proteins: plasminogen activator inhibitor-1, fibronectin, and thrombospondin. Kinetically, the effects on junB and plasminogen activator inhibitor-1 expression occurred faster (half-maximal at 1 to 2 h) than the effects on fibronectin and thrombospondin expression (half-maximal at 6 to 10 h). These effects either preceded or overlapped, respectively, the withdrawal of Mv1Lu cells from the cell cycle. Expression of a transfected T-antigen gene in Mv1Lu cells, however, did not prevent any of these responses to TGF-beta 1. The results indcate that TGF-B1-stimulated expression of junB and extracellular matrix proteins in Mv1Lu cells can occur independently of the T-antigen-sensitive events that lead to growth arrest.

Epithelial Microvesicles Promote an Inflammatory Phenotype in Fibroblasts.

Microvesicles (MVs) are extracellular vesicles secreted by various cell types that are involved in intercellular communication. We hypothesized that in human periodontal disease, the pocket epithelium releases MVs, which then modulate gene expression in the underlying fibroblasts to control periodontal inflammation. MVs were isolated from culture medium of gingival epithelial cells (GECs) treated with oral bacterial biofilm extract or left untreated. Biofilm treatment significantly increased MV release from the GECs. Mass spectrometry of GEC-MVs identified a total of 2,173 proteins, of which about 80% were detected in MVs from both control and biofilm-treated GECs. Among 80 signature genes of human gingival fibroblasts, 20 were significantly regulated (P < 0.05) by MVs from control and biofilm-treated GECs in a similar manner. Matrix metalloproteinase 1 and 3 and interleukin 6 and 8 showed the strongest regulation at the mRNA and protein levels. Several cellular signaling pathways were activated by GEC-MVs in human gingival fibroblasts, including Smad and mitogen-activated protein kinase-associated pathways ERK1/2, JNK, and p38. However, ERK1/2 signaling dominated in the MV-induced gene expression changes. The results demonstrate that GEC-MVs have a strong regulatory effect on the expression of fibroblast genes associated with inflammation and matrix degradation and that bacterial biofilm stimulates the generation of GEC-MVs. This suggests that bacterial biofilms can contribute to the initiation and progression of periodontal disease by promoting a tissue-destructive phenotype in gingival fibroblasts via the enhanced secretion of epithelial MVs.

Interleukin-1 increases collagen production and mRNA levels in cultured skin fibroblasts.

In the present study we show that highly purified human interleukin-1 increases collagen production nearly 2-fold and mRNA levels of type I and III collagen over 2.5-fold in cultured normal human dermal fibroblasts. To minimize the effects of transient prostaglanding E2 production in fibroblasts treated with interleukin-1, the cell cultures were preincubated for 24 h before these measurements were made. The effects of interleukin-1 were also tested on scleroderma fibroblasts exhibiting increased collagen production. Although collagen synthesis was stimulated by interleukin-1 to some degree, the cells grown from both affected and unaffected skin areas were found to be relatively unresponsive to the effects of interleukin-1, suggesting a role for this monokine in the earlier stages of the disease process. The results also suggest that interleukin-1 has a role in stimulation of collagen synthesis under certain normal and pathological conditions in addition to stimulating fibroblast proliferation.

Altered interaction of human granulation-tissue fibroblasts with fibronectin is regulated by alpha 5 beta 1 integrin.

Granulation-tissue fibroblasts express an unique phenotype distinct from normal fibroblasts. Due to the importance of the cell-matrix interactions in the regulation of cell morphology and behavior, we have compared the cell adhesion apparatus, especially integrin-type receptors, in fibroblasts cultured from healthy human periodontal connective tissues and from chronic and wound granulation tissues. The spreading of granulation-tissue cells on fibronectin, but not on type I collagen or laminin, was slower when compared with the normal fibroblasts. Cell spreading on fibronectin could be inhibited by RGD-containing peptide, suggesting integrin-mediated interaction. Both cell types expressed beta 1 integrin subunit, which associated with several integrin alpha subunits, namely alpha 1, alpha 2, alpha 3, alpha 5 and alpha v. In addition to beta 1 subunit, alpha v chain formed heterodimers with beta 3 and beta 5 subunits. Thus, these cells have multiple putative fibronectin, laminin, collagen, and vitronectin receptors. Cell spreading of both cell types on fibronectin was inhibited with anti-beta 1 and anti-alpha 5 antibodies, but antibodies against other putative FN-binding integrins (alpha 3, alpha v, and alpha v beta 3) had no effects. Furthermore, granulation-tissue fibroblasts showed delayed spreading on substrates coated with anti-beta 1 or anti-alpha 5 integrin antibodies. On substrates coated with anti-alpha 3 antibody, both cell types spread equally well. By FACS analysis, the amount of beta 1 and alpha 5 integrin subunits expressed on the cell surfaces was slightly elevated in GTFs compared with HGFs. Thus, the findings in this study indicate that the weakened interaction of granulation-tissue fibroblasts with fibronectin is regulated by altered function of alpha 5 beta 1 integrin.

Interferon-alpha and interferon-gamma reduce excessive collagen synthesis and procollagen mRNA levels of scleroderma fibroblasts in culture.

The effects of interferon-alpha and interferon-gamma on collagen synthesis and mRNA levels of type I and type III procollagens were studied in skin fibroblasts cultured from affected and unaffected skin sites of two patients with localized scleroderma (morphea). Both scleroderma cell lines exhibited elevated type I and type III procollagen mRNA levels to account for the increased procollagen synthesis, when compared to the unaffected controls. Interferon-gamma treatment resulted in a dose-dependent reduction in collagen synthesis and procollagen mRNA levels in scleroderma fibroblasts. A 72-h exposure to interferon-gamma reduced procollagen mRNA levels in the scleroderma fibroblast lines to the levels exhibited by the unaffected control fibroblasts. The suppressive effect of interferon-alpha on procollagen mRNA levels was somewhat weaker than that of interferon-gamma. The results suggest potential use of interferon-gamma in treatment and prevention of human fibrotic conditions.

Cellular recognition and macropinocytosis-like internalization of nanoparticles targeted to integrin α2ß1.

Targeting nanoparticles to desired intracellular compartments is a major challenge. Integrin-type adhesion receptors are connected to different endocytosis routes in a receptor-specific manner. According to our previous observations, the internalization of an α2ß1-integrin-echovirus-1 complex takes place via a macropinocytosis-like mechanism, suggesting that the receptor could be used to target nanoparticles to this specific entry route. Here, silica-based nanoparticles, carrying monoclonal antibodies against the α2ß1 integrin as address labels, were synthesized. Studies with flow cytometry, atomic force microscopy and confocal microscopy showed the particles to attach to the cell surface via the α2ß1 integrin. Furthermore, quantitative analysis of nanoparticle trafficking inside the cell performed with the BioImageXD software indicated that the particles enter cells via a macropinocytosis-like process and end up in caveolin-1 positive structures. Thus, we suggest that different integrins can guide particles to distinct endocytosis routes and, subsequently, also to specific intracellular compartments. In addition, we show that with the BioImageXD software it is possible to conduct sensitive and complex analyses of the behavior of small fluorescent particles inside cells, using basic confocal microscopy images.

Comparative effects of interleukin-1 and tumor necrosis factor-alpha on collagen production and corresponding procollagen mRNA levels in human dermal fibroblasts.

The effects of recombinant human Interleukin-1 alpha (IL-1 alpha), Interleukin-1 beta (IL-1 beta), and Tumor Necrosis Factor-alpha (TNF-alpha) on collagen biosynthesis were studied in vitro using dermal fibroblast cultures. Both forms of IL-1 and TNF-alpha induced a dose-dependent inhibition of both types I and III collagen synthesis, as measured by radioimmunoassay, gel electrophoresis, or collagenase-sensitive material. This effect was accompanied by a significant release of prostaglandin E2 into the culture medium. However, indomethacin, a potent inhibitor of prostaglandin synthesis, could not prevent the inhibitory effect of the three cytokines on collagen synthesis. Measurement of type I and type III procollagen mRNA levels in IL-1 treated cells revealed that both IL-1 alpha and IL-1 beta were potent enhancers of procollagen gene expression at pretranslational level. On the other hand, TNF-alpha was found to reduce the steady-state levels of type I and III procollagen mRNA in a dose-dependent manner. Quantitation of IL-1 beta and TNF-alpha transcripts following TNF-alpha treatment of fibroblasts indicated that this cytokine can induce IL-1 beta gene expression in these cells. By contrast, TNF-alpha mRNA remained at a constant level after TNF-alpha exposure. These data suggest that IL-1 and TNF-alpha, two cytokines that share several biologic activities, modulate collagen deposition in dermal fibroblasts by mechanisms that are clearly different: TNF-alpha appears to act at a transcriptional level to inhibit collagen synthesis, whereas IL-1 inhibitory action involves important translational regulation, still unknown, that counterbalances its stimulatory effect on procollagen mRNA levels. Moreover, our data suggest the existence of local fibroblastic cytokine production that may be involved in the modulation of extracellular matrix deposition.

The collagen receptor integrins have distinct ligand recognition and signaling functions.

Distinct collagen subtypes are recognized by specific cell surface receptors. Two of the best known collagen receptors are members of the integrin family and are named alpha1beta1 and alpha2beta1. Integrin alpha1beta1 is abundant on smooth muscle cells, whereas the alpha2beta1 integrin is the major collagen receptor on epithelial cells and platelets. Many cell types, such as fibroblasts, osteoblasts, chondrocytes, endothelial cells, and lymphocytes may concomitantly express both of the receptors. We have studied the cell biology of these integrins at two levels. First, we have analyzed their ligand binding mechanism and specificity. Second, we have studied their signaling function inside three-dimensional collagen gels. This mini-review summarizes our most recent results. In conclusion, our data indicate that alpha1beta1 and alpha2beta1 integrins have differences in their ligand binding specificity. Furthermore, the two receptors are connected to distinct signaling pathways and their ligation may lead to opposite cellular responses.

Depletion of alphaV integrins from osteosarcoma cells by intracellular antibody expression induces bone differentiation marker genes and suppresses gelatinase (MMP-2) synthesis.

Integrin heterodimers sharing the common alphaV subunit are receptors for adhesion glycoproteins such as vitronectin and fibronectin. They are suggested to play an essential role in cell anchoring, differentiation, and survival. Here, we describe the construction of an expression plasmid coding for an intracellular single-chain antibody against alphaV integrin subunit. Saos-2 osteosarcoma cells transfected with this DNA construct showed an approximately 70-100% decrease in the cell surface expression of alphaVbeta3 and alphaVbeta5 integrins as shown by flow cytometry. Intracellular antibody expression had no effect on the mRNA levels of alphaV integrin. Pulse chase experiments of metabolically labeled integrins showed that the translation of precursor alphaV integrin subunit was not affected. However, the maturation of alphaV integrins as glycoproteins was slow suggesting that the transport from endoplasmic reticulum to Golgi complex was partially prevented. Depletion of alphaV integrins from Saos-2 cells led to a decreased ability to spread on fibronectin and vitronectin. Furthermore, the expression of osteoblast differentiation marker genes, alkaline phosphatase and osteopontin, was induced and concomitantly the expression of matrix metalloproteinase-2 decreased. Thus, alphaV integrins seem to be important regulators of osteosarcoma cell phenotypes. Our data also indicate that the expression of intracellular antibodies is an effective strategy to study the significance of specific integrins for cell phenotype and differentiation.

Changes in the expression of cell surface sialoglycoproteins during transition of human monocytes into macrophages.

Cell surface sialoglycoproteins of human mononuclear phagocytes in different maturation stages were labelled by the periodate/borohydride method and separated by SDS-polyacrylamide gel electrophoresis. The main surface glycoproteins of peripheral blood monocytes had molecular masses of 115 and 95 kDa. During in vitro transition into adherent macrophages, the monocyte-characteristic surface glycoproteins disappeared. Most of the changes in the surface glycoprotein pattern occurred during the first 24 h and after 96 h the changes were completed. The major sialoglycoproteins of the macrophage cell surface had molecular masses of 130 and 55 kDa. The macrophage cell surface showed further changes when cultured in the presence of synovial fluid (10%). These results may reflect the in vivo maturation of monocytes into tissue macrophages. In synovium, tissue-derived factors may also take part in differentiation.

Gene expression of fibroblast matrix proteins is altered by indomethacin.

The role of indomethacin in the regulation of extracellular matrix synthesis was studied in dermal fibroblast cultures. Indomethacin (10 microM) blocked totally the prostaglandin secretion and markedly increased the synthesis of collagen. In parallel, measurement of fibronectin, type I and type III procollagen mRNA levels showed a substantial increase under the action of indomethacin. On the other hand, indomethacin did not modify the mRNA levels of dermatan sulfate proteoglycan core protein. Measurement of collagen production estimated as the amount of collagenase digestible protein and by specific radioimmunoassay indicated a good correlation with the corresponding mRNA levels. These results suggest that indomethacin can regulate the extracellular matrix deposition at a transcriptional level.

Integrin and dystrophin associated adhesion protein complexes during regeneration of shearing-type muscle injury.

In shearing injury both the myofibres and connective tissue framework are breached and the muscle tendon continuity is disrupted. During regeneration the firm myofibre to extracellular matrix (ECM) adhesion must be re-established. We have analysed the expression of selected molecules implementing this adhesion in regenerating myofibres 2-56 days after transection of rat soleus muscle using quantitative immunohistochemistry and Northern blotting. Beta1 integrin mRNA level and alpha7 integrin and vinculin immunoreactivities were transiently increased in both the intact and regenerating parts of the transected myofibres by day 5-7 with normalization by day 10-14. After day 14, alpha7 integrin and vinculin accumulated at the tips of the regenerating myofibres, indicating formation of new mini-myotendinous junctions (mMTJ). Immunoreactivities for dystrophin and associated proteins as well as merosin appeared in regenerating myotubes by day 3-4 reaching control levels by day 56. Our results suggest that integrin and dystrophin associated molecules are complementary in myofibre-ECM adhesion. During regeneration, ruptured myofibres temporarily reinforce their integrin mediated lateral adhesion until mMTJs are formed. Thereby the load on the newly formed scar and the risk of rerupture are reduced. Dystrophin associated molecules appear later and replace integrin on the lateral aspects, while both complexes are abundant at the mMTJs. These molecular events correspond to our previous results on tensile strength.

Regulation of alpha7 integrin by mechanical stress during skeletal muscle regeneration.

The continuity of the tendon-myofibre-tendon units disrupted by shearing injury must be re-established during regeneration. We have previously demonstrated in freely moving rats that transected myofibres reinforce their lateral integrin-mediated adhesion, with the maximum around days 5-7. After day 14, most integrin molecules are redistributed to the newly formed myotendinous junctions, by which the ends of regenerating myofibres attach to the scar between the stumps. Here, we analyzed the effects of mechanical stress (free and forced mobilization vs. immobilization and denervation separately and in combination) on the expression of alpha7 integrin and merosin in regenerating myofibres using quantitative in situ hybridization and immunohistochemistry. In all groups, alpha7 integrin expression was upregulated at mRNA level, whereas increased protein accumulation in lateral sarcolemma occurred only in the mobilized groups. The accumulation of merosin was not affected by the stress level. The results demonstrate that active mechanical stress reinforces early lateral integrin-mediated adhesion; molecules may at the same time mediate signals from matrix to cells for adaptation to the altered biomechanical status.