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Suppressors of cytokine signaling (SOCS) are important regulators of lipopolysaccharide (LPS) and cytokine responses but their role in macrophage polarization is unknown. We have shown here that myeloid-restricted Socs3 deletion (Socs3(Lyz2cre)) resulted in resistance to LPS-induced endotoxic shock, whereas Socs2(-/-) mice were highly susceptible. We observed striking bias toward M2-like macrophages in Socs3(Lyz2cre) mice, whereas the M1-like population was enriched in Socs2(-/-) mice. Adoptive transfer experiments showed that responses to endotoxic shock and polymicrobial sepsis were transferable and macrophage dependent. Critically, this dichotomous response was associated with enhanced regulatory T (Treg) cell recruitment by Socs3(Lyz2cre) cells, whereas Treg cell recruitment was absent in the presence of Socs2(-/-) macrophages. In addition, altered polarization coincided with enhanced interferon-gamma (IFN-γ)-induced signal transducer and activator of transcription-1 (STAT1) activation in Socs2(-/-) macrophages and enhanced interleukin-4 (IL-4) plus IL-13-induced STAT6 phosphorylation in Socs3(Lyz2cre) macrophages. SOCS, therefore, are essential controllers of macrophage polarization, regulating inflammatory responses.
Assuntos
Polaridade Celular/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética , Transferência Adotiva , Animais , Regulação da Expressão Gênica , Interleucina-10/imunologia , Interleucina-10/metabolismo , Macrófagos/transplante , Camundongos , Fatores de Transcrição STAT/metabolismo , Sepse/genética , Sepse/imunologia , Sepse/prevenção & controle , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Transplante IsogênicoRESUMO
In this work, we developed a lipid mixture based on phytantriol / polyoxyethylene surfactant (Brij-56) that forms aIm3msymmetry bicontinuous cubic phase based on the Schwartz primitive surface (QIIP), from which we templated highly ordered 3D nanoporous platinum with a novel 'single primitive' morphology (Pm3msymmetry). TheQIIPtemplate phase is obtained by incorporation of 17.5% w/w Brij-56 (C16EO10) (a type-I surfactant) into phytantriol under excess hydration conditions. Phytantriol alone forms the double diamondQIID(Pn3m) phase, and in previous studies incorporating Brij-56 at different compositions the cubic phase maintained this morphology, but increased its lattice parameter; mesoporous metals templated from theseQIIDlipid templates all exhibited the 'single diamond' (Fd3m) morphology. In contrast, the current paper presents the availability of ourQIIPcubic phases to template nanoporous materials of single primitivePm3mmorphology via chemical and electrochemical methods. To explore the structure porosity and morphological features of the templated Pt material, x-ray scattering and transmission electron microscopy are used. The resulting 3D nanoporous Pt materials are found to exhibit a regular network of Pt nanowires of â¼4 nm in diameter with a unit cell dimension of 14.8 ± 0.8 nm, reflecting the aqueous network within theQIIPtemplate.
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BACKGROUND: Fractures of the proximal humerus, often termed shoulder fractures, are common injuries, especially in older people. The management of these fractures varies widely, including in the use of surgery. This is an update of a Cochrane Review first published in 2001 and last updated in 2015. OBJECTIVES: To assess the effects (benefits and harms) of treatment and rehabilitation interventions for proximal humeral fractures in adults. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, trial registries, and bibliographies of trial reports and systematic reviews to September 2020. We updated this search in November 2021, but have not yet incorporated these results. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials that compared non-pharmacological interventions for treating acute proximal humeral fractures in adults. DATA COLLECTION AND ANALYSIS: Pairs of review authors independently selected studies, assessed risk of bias and extracted data. We pooled data where appropriate and used GRADE for assessing the certainty of evidence for each outcome. We prepared a brief economic commentary for one comparison. MAIN RESULTS: We included 47 trials (3179 participants, mostly women and mainly aged 60 years or over) that tested one of 26 comparisons. Six comparisons were tested by 2 to 10 trials, the others by small single-centre trials only. Twelve studies evaluated non-surgical treatments, 10 compared surgical with non-surgical treatments, 23 compared two methods of surgery, and two tested timing of mobilisation after surgery. Most trials were at high risk of bias, due mainly to lack of blinding. We summarise the findings for four key comparisons below. Early (usually one week post injury) versus delayed (after three or more weeks) mobilisation for non-surgically-treated fractures Five trials (350 participants) made this comparison; however, the available data are very limited. Due to very low-certainty evidence from single trials, we are uncertain of the findings of better shoulder function at one year in the early mobilisation group, or the findings of little or no between-group difference in function at 3 or 24 months. Likewise, there is very low-certainty evidence of no important between-group difference in quality of life at one year. There was one reported death and five serious shoulder complications (1.9% of 259 participants), spread between the two groups, that would have required substantive treatment. Surgical versus non-surgical treatment Ten trials (717 participants) evaluated surgical intervention for displaced fractures (66% were three- or four-part fractures). There is high-certainty evidence of no clinically important difference between surgical and non-surgical treatment in patient-reported shoulder function at one year (standardised mean difference (SMD) 0.10, 95% confidence interval (CI) -0.07 to 0.27; 7 studies, 552 participants) and two years (SMD 0.06, 95% CI -0.13 to 0.25; 5 studies, 423 participants). There is moderate-certainty evidence of no clinically important between-group difference in patient-reported shoulder function at six months (SMD 0.17, 95% CI -0.04 to 0.38; 3 studies, 347 participants). There is high-certainty evidence of no clinically important between-group difference in quality of life at one year (EQ-5D (0: dead to 1: best quality): mean difference (MD) 0.01, 95% CI -0.02 to 0.04; 6 studies, 502 participants). There is low-certainty evidence of little between-group difference in mortality: one of the 31 deaths was explicitly linked with surgery (risk ratio (RR) 1.35, 95% CI 0.70 to 2.62; 8 studies, 646 participants). There is low-certainty evidence of a higher risk of additional surgery in the surgery group (RR 2.06, 95% CI 1.21 to 3.51; 9 studies, 667 participants). Based on an illustrative risk of 35 subsequent operations per 1000 non-surgically-treated patients, this indicates an extra 38 subsequent operations per 1000 surgically-treated patients (95% CI 8 to 94 more). Although there was low-certainty evidence of a higher overall risk of adverse events after surgery, the 95% CI also includes a slightly increased risk of adverse events after non-surgical treatment (RR 1.46, 95% CI 0.92 to 2.31; 3 studies, 391 participants). Open reduction and internal fixation with a locking plate versus a locking intramedullary nail Four trials (270 participants) evaluated surgical intervention for displaced fractures (63% were two-part fractures). There is low-certainty evidence of no clinically important between-group difference in shoulder function at one year (SMD 0.15, 95% CI -0.12 to 0.41; 4 studies, 227 participants), six months (Disability of the Arm, Shoulder, and Hand questionnaire (0 to 100: worst disability): MD -0.39, 95% CI -4.14 to 3.36; 3 studies, 174 participants), or two years (American Shoulder and Elbow Surgeons score (ASES) (0 to 100: best outcome): MD 3.06, 95% CI -0.05 to 6.17; 2 studies, 101 participants). There is very low-certainty evidence of no between-group difference in quality of life (1 study), and of little difference in adverse events (4 studies, 250 participants) and additional surgery (3 studies, 193 participants). Reverse total shoulder arthroplasty (RTSA) versus hemiarthroplasty There is very low-certainty evidence from two trials (161 participants with either three- or four-part fractures) of no or minimal between-group differences in self-reported shoulder function at one year (1 study) or at two to three years' follow-up (2 studies); or in quality of life at one year or at two or more years' follow-up (1 study). Function at six months was not reported. Of 10 deaths reported by one trial (99 participants), one appeared to be surgery-related. There is very low-certainty evidence of a lower risk of complications after RTSA (2 studies). Ten people (6.2% of 161 participants) had a reoperation; all eight cases in the hemiarthroplasty group received a RTSA (very low-certainty evidence). AUTHORS' CONCLUSIONS: There is high- or moderate-certainty evidence that, compared with non-surgical treatment, surgery does not result in a better outcome at one and two years after injury for people with displaced proximal humeral fractures. It may increase the need for subsequent surgery. The evidence is absent or insufficient for people aged under 60 years, high-energy trauma, two-part tuberosity fractures or less common fractures, such as fracture dislocations and articular surface fractures. There is insufficient evidence from randomised trials to inform the choices between different non-surgical, surgical or rehabilitation interventions for these fractures.
Assuntos
Artroplastia do Ombro , Fraturas do Ombro , Adulto , Idoso , Feminino , Fixação de Fratura , Humanos , Masculino , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Fraturas do Ombro/reabilitação , Fraturas do Ombro/cirurgiaRESUMO
We present an attractive method for the fabrication of long, straight, highly crystalline, ultrathin platinum nanowires. The fabrication is simply achieved using an inverse hexagonal (HII) lyotropic liquid crystal phase of the commercial surfactant phytantriol as a template. A platinum precursor dissolved within the cylindrical aqueous channels of the liquid crystal phase is chemically reduced by galvanic displacement using stainless steel. We demonstrate the production of nanowires using the HII phase in the phytantriol/water system which we obtain either by heating to 55 °C or at room temperature by the addition of a hydrophobic liquid, 9- cis-tricosene, to relieve packing frustration. The two sets of conditions produced high aspect nanowires with diameters of 2.5 and 1.7 nm, respectively, at least hundreds of nanometers in length, matching the size of the aqueous channels in which they grow. This versatile approach can be extended to produce highly uniform nanowires from a range of metals.
RESUMO
BACKGROUND: Wrist fractures, involving the distal radius, are the most common fractures in children. Most are buckle fractures, which are stable fractures, unlike greenstick and other usually displaced fractures. There is considerable variation in practice, such as the extent of immobilisation for buckle fractures and use of surgery for seriously displaced fractures. OBJECTIVES: To assess the effects (benefits and harms) of interventions for common distal radius fractures in children, including skeletally immature adolescents. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group's Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, trial registries and reference lists to May 2018. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing interventions for treating distal radius fractures in children. We sought data on physical function, treatment failure, adverse events, time to return to normal activities (recovery time), wrist pain, and child (and parent) satisfaction. DATA COLLECTION AND ANALYSIS: At least two review authors independently performed study screening and selection, 'Risk of bias' assessment and data extraction. We pooled data where appropriate and used GRADE for assessing the quality of evidence for each outcome. MAIN RESULTS: Of the 30 included studies, 21 were RCTs, seven were quasi-RCTs and two did not describe their randomisation method. Overall, 2930 children were recruited. Typically, trials included more male children and reported mean ages between 8 and 10 years. Eight studies recruited buckle fractures, five recruited buckle and other stable fractures, three recruited minimally displaced fractures and 14 recruited displaced fractures, typically requiring closed reduction, typically requiring closed reduction. All studies were at high risk of bias, mainly reflecting lack of blinding. The studies made 14 comparisons. Below we consider five prespecified comparisons:Removable splint versus below-elbow cast for predominantly buckle fractures (6 studies, 695 children)One study (66 children) reported similar Modified Activities Scale for Kids - Performance scores (0 to 100; no disability) at four weeks (median scores: splint 99.04; cast 99.11); low-quality evidence. Thirteen children needed a change or reapplication of device (splint 5/225; cast 8/219; 4 studies); very low-quality evidence. One study (87 children) reported no refractures at six months. One study (50 children) found no between-group difference in pain during treatment; very low-quality evidence. Evidence was absent (recovery time), insufficient (children with minor complications) or contradictory (child or parent satisfaction). Two studies estimated lower healthcare costs for removable splints.Soft or elasticated bandage versus below-elbow cast for buckle or similar fractures (4 studies, 273 children)One study (53 children) reported more children had no or only limited disability at four weeks in the bandage group; very low-quality evidence. Eight children changed device or extended immobilisation for delayed union (bandage 5/90; cast 3/91; 3 studies); very low-quality evidence. Two studies (139 children) reported no serious adverse events at four weeks. Evidence was absent, insufficient or contradictory for recovery time, wrist pain, children with minor complications, and child and parent satisfaction. More bandage-group participants found their treatment convenient (39 children).Removal of casts at home by parents versus at the hospital fracture clinic by clinicians (2 studies, 404 children, mainly buckle fractures)One study (233 children) found full restoration of physical function at four weeks; low-quality evidence. There were five treatment changes (home 4/197; hospital 1/200; 2 studies; very low-quality evidence). One study found no serious adverse effects at six months (288 children). Recovery time and number of children with minor complications were not reported. There was no evidence of a difference in pain at four weeks (233 children); low-quality evidence. One study (80 children) found greater parental satisfaction in the home group; low-quality evidence. One UK study found lower healthcare costs for home removal.Below-elbow versus above-elbow casts for displaced or unstable both-bone fractures (4 studies, 399 children)Short-term physical function data were unavailable but very low-quality evidence indicated less dependency when using below-elbow casts. One study (66 children with minimally displaced both-bone fractures) found little difference in ABILHAND-Kids scores (0 to 42; no problems) (mean scores: below-elbow 40.7; above-elbow 41.8); very low-quality evidence. Overall treatment failure data are unavailable, but nine of the 11 remanipulations or secondary reductions (366 children, 4 studies) were in the above-elbow group; very low-quality evidence. There was no refracture or compartment syndrome at six months (215 children; 2 studies). Recovery time and overall numbers of children with minor complications were not reported. There was little difference in requiring physiotherapy for stiffness (179 children, 2 studies); very low-quality evidence. One study (85 children) found less pain at one week for below-elbow casts; low-quality evidence. One study found treatment with an above-elbow cast cost three times more in Nepal.Surgical fixation with percutaneous wiring and cast immobilisation versus cast immobilisation alone after closed reduction of displaced fractures (5 studies, 323 children)Where reported, above-elbow casts were used. Short-term functional outcome data were unavailable. One study (123 children) reported similar ABILHAND-Kids scores indicating normal physical function at six months (mean scores: surgery 41.9; cast only 41.4); low-quality evidence. There were fewer treatment failures, defined as early or problematic removal of wires or remanipulation for early loss in position, after surgery (surgery 20/124; cast only 41/129; 4 studies; very low-quality evidence). Similarly, there were fewer serious advents after surgery (surgery 28/124; cast only 43/129; 4 studies; very low-quality evidence). Recovery time, wrist pain, and satisfaction were not reported. There was lower referral for physiotherapy for stiffness after surgery (1 study); very low-quality evidence. One USA study found similar treatment costs in both groups. AUTHORS' CONCLUSIONS: Where available, the quality of the RCT-based evidence on interventions for treating wrist fractures in children is low or very low. However, there is reassuring evidence of a full return to previous function with no serious adverse events, including refracture, for correctly-diagnosed buckle fractures, whatever the treatment used. The review findings are consistent with the move away from cast immobilisation for these injuries. High-quality evidence is needed to address key treatment uncertainties; notably, some priority topics are already being tested in ongoing multicentre trials, such as FORCE.
Assuntos
Bandagens/estatística & dados numéricos , Fixação de Fratura/métodos , Fraturas do Rádio/terapia , Contenções/estatística & dados numéricos , Adolescente , Criança , Feminino , Fixação de Fratura/efeitos adversos , Consolidação da Fratura , Humanos , Imobilização/métodos , Imobilização/estatística & dados numéricos , Masculino , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Falha de Tratamento , Traumatismos do PunhoRESUMO
BACKGROUND: Fracture of the distal radius is a common clinical problem, particularly in older people with osteoporosis. There is considerable variation in the management, including rehabilitation, of these fractures. This is an update of a Cochrane review first published in 2002 and last updated in 2006. OBJECTIVES: To examine the effects of rehabilitation interventions in adults with conservatively or surgically treated distal radial fractures. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL 2014; Issue 12), MEDLINE, EMBASE, CINAHL, AMED, PEDro, OTseeker and other databases, trial registers, conference proceedings and reference lists of articles. We did not apply any language restrictions. The date of the last search was 12 January 2015. SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-RCTs evaluating rehabilitation as part of the management of fractures of the distal radius sustained by adults. Rehabilitation interventions such as active and passive mobilisation exercises, and training for activities of daily living, could be used on their own or in combination, and be applied in various ways by various clinicians. DATA COLLECTION AND ANALYSIS: The review authors independently screened and selected trials, and reviewed eligible trials. We contacted study authors for additional information. We did not pool data. MAIN RESULTS: We included 26 trials, involving 1269 mainly female and older patients. With few exceptions, these studies did not include people with serious fracture or treatment-related complications, or older people with comorbidities and poor overall function that would have precluded trial participation or required more intensive treatment. Only four of the 23 comparisons covered by these 26 trials were evaluated by more than one trial. Participants of 15 trials were initially treated conservatively, involving plaster cast immobilisation. Initial treatment was surgery (external fixation or internal fixation) for all participants in five trials. Initial treatment was either surgery or plaster cast alone in six trials. Rehabilitation started during immobilisation in seven trials and after post-immobilisation in the other 19 trials. As well as being small, the majority of the included trials had methodological shortcomings and were at high risk of bias, usually related to lack of blinding, that could affect the validity of their findings. Based on GRADE criteria for assessment quality, we rated the evidence for each of the 23 comparisons as either low or very low quality; both ratings indicate considerable uncertainty in the findings.For interventions started during immobilisation, there was very low quality evidence of improved hand function for hand therapy compared with instructions only at four days after plaster cast removal, with some beneficial effects continuing one month later (one trial, 17 participants). There was very low quality evidence of improved hand function in the short-term, but not in the longer-term (three months), for early occupational therapy (one trial, 40 participants), and of a lack of differences in outcome between supervised and unsupervised exercises (one trial, 96 participants).Four trials separately provided very low quality evidence of clinically marginal benefits of specific interventions applied in addition to standard care (therapist-applied programme of digit mobilisation during external fixation (22 participants); pulsed electromagnetic field (PEMF) during cast immobilisation (60 participants); cyclic pneumatic soft tissue compression using an inflatable cuff placed under the plaster cast (19 participants); and cross-education involving strength training of the non-fractured hand during cast immobilisation with or without surgical repair (39 participants)).For interventions started post-immobilisation, there was very low quality evidence from one study (47 participants) of improved function for a single session of physiotherapy, primarily advice and instructions for a home exercise programme, compared with 'no intervention' after cast removal. There was low quality evidence from four heterogeneous trials (30, 33, 66 and 75 participants) of a lack of clinically important differences in outcome in patients receiving routine physiotherapy or occupational therapy in addition to instructions for home exercises versus instructions for home exercises from a therapist. There was very low quality evidence of better short-term hand function in participants given physiotherapy than in those given either instructions for home exercises by a surgeon (16 participants, one trial) or a progressive home exercise programme (20 participants, one trial). Both trials (46 and 76 participants) comparing physiotherapy or occupational therapy versus a progressive home exercise programme after volar plate fixation provided low quality evidence in favour of a structured programme of home exercises preceded by instructions or coaching. One trial (63 participants) provided very low quality evidence of a short-term, but not persisting, benefit of accelerated compared with usual rehabilitation after volar plate fixation.For trials testing single interventions applied post-immobilisation, there was very low quality evidence of no clinically significant differences in outcome in patients receiving passive mobilisation (69 participants, two trials), ice (83 participants, one trial), PEMF (83 participants, one trial), PEMF plus ice (39 participants, one trial), whirlpool immersion (24 participants, one trial), and dynamic extension splint for patients with wrist contracture (40 participants, one trial), compared with no intervention. This finding applied also to the trial (44 participants) comparing PEMF versus ice, and the trial (29 participants) comparing manual oedema mobilisation versus traditional oedema treatment. There was very low quality evidence from single trials of a short-term benefit of continuous passive motion post-external fixation (seven participants), intermittent pneumatic compression (31 participants) and ultrasound (38 participants). AUTHORS' CONCLUSIONS: The available evidence from RCTs is insufficient to establish the relative effectiveness of the various interventions used in the rehabilitation of adults with fractures of the distal radius. Further randomised trials are warranted. However, in order to optimise research effort and engender the large multicentre randomised trials that are required to inform practice, these should be preceded by research that aims to identify priority questions.
Assuntos
Fraturas do Rádio/reabilitação , Traumatismos do Punho/reabilitação , Adulto , Idoso , Feminino , Fraturas Ósseas/reabilitação , Humanos , Masculino , Modalidades de Fisioterapia , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Lipid cubic phase films are of increasingly widespread importance, both in the analysis of the cubic phases themselves by techniques including microscopy and X-ray scattering, and in their applications, especially as electrode coatings for electrochemical sensors and for templates for the electrodeposition of nanostructured metal. In this work we demonstrate that the crystallographic orientation adopted by these films is governed by minimization of interfacial energy. This is shown by the agreement between experimental data obtained using grazing-incidence small-angle X-ray scattering (GI-SAXS), and the predicted lowest energy orientation determined using a theoretical approach we have recently developed. GI-SAXS data show a high degree of orientation for films of both the double diamond phase and the gyroid phase, with the [111] and [110] directions respectively perpendicular to the planar substrate. In each case, this matches the lowest energy facet calculated for that particular phase.
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The synthesis of a dithiol-functionalized pyrene derivative is reported, together with studies of interactions between this receptor (and other related pyrenes) and nitroaromatic compounds (NACs), in both solution and in the solid state. Spectroscopic analysis in solution and X-ray crystallographic analysis of cocrystals of pyrene and NACs in the solid state indicate that supramolecular interactions lead to the formation of defined π-π stacked complexes. The dithiol-functionalized pyrene derivative can be used to modify the surface of a gold quartz crystal microbalance (QCM) to create a unique π-electron rich surface, which is able to interact with electron poor aromatic compounds. For example, exposure of the modified QCM surface to the nitroaromatic compound 2,4-dinitrotoluene (DNT) in solution results in a reduction in the resonant frequency of the QCM as a result of supramolecular interactions between the electron-rich pyrenyl surface layer and the electron-poor DNT molecules. These results suggest the potential use of such modified QCM surfaces for the detection of explosive NACs.
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Although production of cytokines by TLR is essential for viral and bacterial clearance, overproduction can be detrimental, thus controlling these responses is essential. CD33-related sialic acid binding Ig-like lectin receptors (Siglecs) have been implicated in the control of leukocyte responses. In this study, we report that murine Siglec-E is induced by TLRs in a MyD88-specific manner, is tyrosine phosphorylated following LPS stimulation, and negatively regulates TLR responses. Specifically, we demonstrate the Siglec-E expression inhibits TLR-induced NF-kappaB and more importantly, the induction of the antiviral cytokines IFN-beta and RANTES. Siglec-E mediates its inhibitory effects on TIR domain containing adaptor inducing IFN-beta (TRIF)-dependent cytokine production via recruitment of the tyrosine [corrected] phosphatase SHP2 and subsequent inhibition of TBK1 activity as evidenced by enhanced TBK1 phosphorylation in cells following knockdown of Siglec-E expression. Taken together, our results demonstrate a novel role for Siglec-E in controlling the antiviral response to TLRs and thus helping to maintain a healthy cytokine balance following infection.
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Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos B/biossíntese , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Regulação para Baixo/imunologia , Lipopolissacarídeos/farmacologia , Receptores Toll-Like/antagonistas & inibidores , Receptores Toll-Like/fisiologia , Regulação para Cima/imunologia , Proteínas Adaptadoras de Transporte Vesicular/antagonistas & inibidores , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/fisiologia , Animais , Antígenos CD/metabolismo , Antígenos CD/fisiologia , Antígenos de Diferenciação de Linfócitos B/metabolismo , Antígenos de Diferenciação de Linfócitos B/fisiologia , Linhagem Celular , Linhagem Celular Transformada , Citocinas/genética , Regulação para Baixo/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/fisiologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Fosforilação/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/imunologiaRESUMO
Recently several different JAK2 exon12 mutations have been identified in V617F negative polycythaemia vera (PV) or idiopathic erythrocytosis (IE) patients. The patients present with erythrocytosis, ligand-independent cell growth and low serum erythropoietin (EPO) levels. Within this group, a deletion of amino acids 542-543 (N542-E543del) of JAK2 is most prevalent. We have previously shown that in the presence of JAK2(V617F), suppressor of cytokine signalling 3 (SOCS3) is unable to negatively regulate EPO signalling and proliferation of V617F-expressing cells. Here we report a PV patient heterozygous for the somatic JAK2(N542-E543del) mutation and a previously unreported germline mutation within the SH2 domain of SOCS3 (F136L). Interestingly, the SOCS3(F136L) mutation was detected in a Japanese myeloproliferative disorder patient cohort at double the frequency of healthy controls. Cells expressing SOCS3(F136L) had markedly elevated EPO-induced proliferation and extended EPO-induced JAK2 phosphorylation. Additionally, compared to wild-type SOCS3, mutant SOCS3 had an extended half-life in the presence of JAK2 and JAK2(N542-E543del). Our findings suggest that this loss-of-function SOCS3 mutation may have contributed to disease onset by causing deregulated JAK2 signalling in the presence of a constitutively active JAK2(N542-E543del) mutant.
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Eritropoetina/fisiologia , Mutação em Linhagem Germinativa , Policitemia Vera/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Adulto , Sequência de Bases , Proliferação de Células , Células Cultivadas , Eritropoetina/sangue , Feminino , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Mutação , Fosforilação , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/fisiologiaRESUMO
JAK2 V617F, identified in the majority of patients with myeloproliferative neoplasms, tyrosine phosphorylates SOCS3 and escapes its inhibition. Here, we demonstrate that the JAK2 exon 12 mutants described in a subset of V617F-negative MPN cases, also stabilize tyrosine phosphorylated SOCS3. SOCS3 tyrosine phosphorylation was also observed in peripheral blood mononuclear cells and granulocytes isolated from patients with JAK2 H538QK539L or JAK2 F537-K539delinsL mutations. JAK kinase inhibitors, which effectively inhibited the proliferation of cells expressing V617F or K539L, also caused a dose-dependent reduction in both mutant JAK2 and SOCS3 tyrosine phosphorylation. We propose, therefore, that SOCS3 tyrosine phosphorylation may be a novel bio-marker of myeloproliferative neoplasms resulting from a JAK2 mutation and a potential reporter of effective JAK2 inhibitor therapy currently in clinical development.
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Janus Quinase 2/genética , Mutação , Transtornos Mieloproliferativos/diagnóstico , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Animais , Biomarcadores Tumorais , Linhagem Celular , Proliferação de Células , Éxons , Humanos , Camundongos , Transtornos Mieloproliferativos/genética , Fosforilação , Proteína 3 Supressora da Sinalização de Citocinas , Linfócitos T , Tirosina/metabolismoRESUMO
Cytokine responses can be regulated by a family of proteins termed suppressors of cytokine signaling (SOCS) which can inhibit the JAK/STAT pathway in a classical negative-feedback manner. While the SOCS are thought to target signaling intermediates for degradation, relatively little is known about how their turnover is regulated. Unlike other SOCS family members, we find that SOCS2 can enhance interleukin-2 (IL-2)- and IL-3-induced STAT phosphorylation following and potentiate proliferation in response to cytokine stimulation. As a clear mechanism for these effects, we demonstrate that expression of SOCS2 results in marked proteasome-dependent reduction of SOCS3 and SOCS1 protein expression. Furthermore, we provide evidence that this degradation is dependent on the presence of an intact SOCS box and that the loss of SOCS3 is enhanced by coexpression of elongin B/C. This suggests that SOCS2 can bind to SOCS3 and elongin B/C to form an E3 ligase complex resulting in the degradation of SOCS3. Therefore, SOCS2 can enhance cytokine responses by accelerating proteasome-dependent turnover of SOCS3, suggesting a mechanism for the gigantism observed in SOCS2 transgenic mice.
Assuntos
Interleucina-2/metabolismo , Interleucina-3/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Animais , Sequência de Bases , Linhagem Celular , DNA Complementar/genética , Humanos , Técnicas In Vitro , Camundongos , Camundongos Transgênicos , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/genética , Linfócitos T/metabolismoRESUMO
STUDY OBJECTIVES: The pattern and distribution of rapid eye movement (REM) sleep changes during development, yet there have been few studies of REM density in children. Although children with obstructive apnea syndrome (OSAS) obstruct primarily during REM sleep, the relationship between REM density and obstructive apnea has not been established for this population. We hypothesized that (i) REM density and REM cycle duration increases over the course of the night in children, (ii) the duty cycle (inspiratory time divided by respiratory cycle time) increases over the course of the night in children with suspected OSAS, and (iii) the increase in REM density over the course of the night is associated with increased severity of obstructive apnea. DESIGN: REM density and respiratory parameters were measured during polysomnography. SETTING: Sleep laboratory PATIENTS: 76 children with suspected OSAS. INTERVENTIONS: NA MEASUREMENTS AND RESULTS: REM density and the duration of REM cycles increased over the course of the night until the fifth REM cycle, and then stabilized. The duty cycle increased across the first 6 REM cycles. However, the apnea hypopnea index (AHI) did not increase across REM cycles, and was not affected by the changes in REM density or duty cycle. We speculate that the increase in the duty cycle is a compensatory response to increased upper airway loads during sleep, and that this may lead to ventilatory or upper airway muscle fatigue.
Assuntos
Apneia Obstrutiva do Sono/fisiopatologia , Sono REM/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Laboratórios , Masculino , Polissonografia , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/diagnósticoRESUMO
From the last couple of decades, lyotropic liquid crystals have garnered enormous attentions in medical and pharmaceutical sciences. Non-toxic, chemically stable, and biocompatible properties of these liquid crystal systems are contributing to their applications for drug delivery. Among a large variety of liquid crystal phases, inverse bicontinuous cubic and inverse hexagonal mesophases have been extensively investigated for their ability to encapsulate and controlled release of bioactive molecules of various sizes and polarity. The concept of changing the drug release rate in situ by simply changing the mesophase structure is much more fascinating. The encapsulation of bioactive compounds in mesophase systems of desirable features in sub-micron sized particles such as hexosomes and cubosomes, at ambient and high temperature is bringing innovation in the development of new drug applications. This review article outlines unique structural features of cubosomes and hexosomes, their methods of productions, factors affecting their formations and their potential utilization as smart nano-carriers for biopharmaceuticals in drug delivery applications.
Assuntos
Portadores de Fármacos/química , Álcoois Graxos/química , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Cristais Líquidos/química , Tamanho da PartículaRESUMO
We describe a method to predict and control the lattice parameters of hexagonal and gyroid mesoporous materials formed by liquid crystal templating. In the first part, we describe a geometric model with which the lattice parameters of different liquid crystal mesophases can be predicted as a function of their water/surfactant/oil volume fractions, based on certain geometric parameters relating to the constituent surfactant molecules. We demonstrate the application of this model to the lamellar (Lα), hexagonal (H1), and gyroid bicontinuous cubic (V1) mesophases formed by the binary Brij-56 (C16EO10)/water system and the ternary Brij-56/hexadecane/water system. In this way, we demonstrate predictable and independent control over the size of the cylinders (with hexadecane) and their spacing (with water). In the second part, we produce mesoporous platinum using as templates hexagonal and gyroid phases with different compositions and show that in each case the symmetry and lattice parameter of the metal nanostructure faithfully replicate those of the liquid crystal template, which is itself in agreement with the model. This demonstrates a rational control over the geometry, size, and spacing of pores in a mesoporous metal.
RESUMO
Melanin-concentrating hormone (MCH) is a hypothalamic neuropeptide that stimulates feeding and increases body weight in rodents. We studied the role of the system in energy homeostasis and its regulation by the satiety signals, leptin and insulin. We used real-time PCR to measure the hypothalamic expression of MCH and its receptor (MCHR1) in two contrasting models of altered nutritional status, namely, obesity induced by 8 weeks' voluntary overeating and food restriction for 10 days. Diet-fed rats were stratified according to final total fat-pad mass into a 'high fat gain' group (HG) and 'low fat gain' group (LG). MCH mRNA levels were increased by 31% (p>0.05) and 49% (p<0.05) in the LG and HG, respectively, compared with controls. MCHR1 mRNA levels rose by 118% in the LG (p<0.01) and 85% in the HG (p<0.01). There were significant positive correlations (p<0.05) between plasma leptin concentration and both MCH and MCHR1 mRNA levels, and between plasma insulin and MCHR1 expression. A positive correlation was also observed between MCH and MCHR1 mRNA levels (p<0.05). Food-restricted rats showed no significant alterations in the levels of either MCH mRNA or MCHR1 mRNA. In a second experiment, we measured MCH peptide levels in five discrete hypothalamic areas of dietary-obese rats. MCH concentrations were significantly increased in the arcuate nuclei of the HG (p<0.05) and the paraventricular nuclei of both the LG (p<0.05) and HG (p<0.05), compared with their lean counterparts. These results suggest that the MCH system becomes more active in dietary obesity and could be involved in enhancing appetite for palatable food. The possibility that MCH and MCHR1 expression are positively regulated by leptin and insulin, which normally inhibit feeding, is a putative explanation for how appetite for palatable food is able to override mechanisms that prevent the development of obesity.
Assuntos
Dieta/efeitos adversos , Hormônios Hipotalâmicos/metabolismo , Hipotálamo/metabolismo , Melaninas/metabolismo , Obesidade/metabolismo , Hormônios Hipofisários/metabolismo , Receptores do Hormônio Hipofisário/metabolismo , Animais , Glicemia , Índice de Massa Corporal , Peso Corporal , Hormônios Hipotalâmicos/genética , Insulina/sangue , Leptina/sangue , Masculino , Melaninas/genética , Obesidade/induzido quimicamente , Hormônios Hipofisários/genética , RNA Mensageiro/biossíntese , Radioimunoensaio/métodos , Ratos , Receptores do Hormônio Hipofisário/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
Agonists at cannabinoid-1 (CB-1) receptors stimulate feeding and particularly enhance the reward aspects of eating. To investigate whether endogenous cannabinoids might influence appetite for palatable food, we compared CB-1 receptor density in the forebrain and hypothalamus, between rats fed standard chow (n=8) and others given palatable food (n=8) for 10 weeks to induce dietary obesity. CB-1 receptor density was significantly decreased by 30-50% (P<0.05) in the hippocampus, cortex, nucleus accumbens and entopeduncular nucleus of diet-fed rats. Furthermore, CB-1 receptor density in the hippocampus, nucleus accumbens and entopeduncular nucleus was significantly inversely correlated with intake of palatable food (r(2)=0.25-0.35; all P<0.05). By contrast, CB-1 receptor binding in the hypothalamus was low and not altered in diet-fed rats. CB-1 receptor down-regulation is consistent with increased activation of these receptors by endogenous cannabinoids. Acting in areas such as the nucleus accumbens and hippocampus, which are involved in the hedonic aspects of eating, cannabinoids may therefore drive appetite for palatable food and thus determine total energy intake and the severity of diet-induced obesity. However, cannabinoids in the hypothalamus do not appear to influence this aspect of eating behaviour.
Assuntos
Apetite/fisiologia , Regulação para Baixo/fisiologia , Ácidos Graxos Insaturados/fisiologia , Hipotálamo/metabolismo , Obesidade/metabolismo , Receptores de Droga/antagonistas & inibidores , Receptores de Droga/biossíntese , Animais , Regulação do Apetite/fisiologia , Moduladores de Receptores de Canabinoides , Ingestão de Energia/fisiologia , Masculino , Ratos , Ratos Wistar , Receptores de CanabinoidesRESUMO
The hypothalamus and other brain regions that control energy homeostasis contain neuronal populations that produce specific neuropeptides which have experimental effects on feeding behavior and body weight. Here, we describe examples of neuropeptides that exert 'anabolic' effects, notably stimulation of feeding and increased body weight. Neuropeptide Y (NPY) neurons in the hypothalamic arcuate nucleus (ARC) are inhibited by leptin and insulin, and thus are stimulated in states of energy deficit and fat loss, e.g., underfeeding. NPY neuronal overactivity contributes to enhanced hunger and food-seeking activity under these conditions. The lateral hypothalamic area (LHA) contains specific neuronal populations that affect feeding in different ways. Neurons expressing the appetite-stimulating peptide orexin A are stimulated by starvation (but not food restriction) and by hypoglycemia, but only if food is withheld. Orexin neurons are apparently activated by low glucose but are promptly inhibited by visceral feeding signals, probably mediated via vagal sensory pathway and the nucleus of the solitary tract (NTS); a short-term role in initiating feeding seems most likely. Other LHA neurons express melanin-concentrating hormone (MCH), which transiently increases food intake when injected centrally. MCH neurons may be regulated by leptin, insulin and glucose. Glucose-sensing neurons in the hypothalamus and elsewhere are sensitive to other cues of nutritional state, including visceral satiety signals (transmitted via the vagus) and orexin A. Thus, long- and short-term humoral and neural signals interact with each other to meet diverse nutritional needs, and anabolic neuropeptides are important in the overall integration of energy homeostasis. Clarifying the underlying mechanisms will be essential to understanding normal energy balance and the pathogenesis and treatment of disorders, such as obesity and cachexia.
Assuntos
Anabolizantes/metabolismo , Peso Corporal/fisiologia , Comportamento Alimentar/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Neuropeptídeos/fisiologia , Animais , Proteínas de Transporte/fisiologia , Hormônios Hipotalâmicos/fisiologia , Melaninas/fisiologia , Neuropeptídeo Y/fisiologia , Orexinas , Hormônios Hipofisários/fisiologiaRESUMO
OBJECTIVES: We aimed to develop and pilot a process for joint working between Cochrane Review Groups (specialist-area groups responsible for producing Cochrane reviews) and Cochrane Fields (broad-spectrum interest groups), for identifying high priority review topics and enhancing quality and dissemination of priority reviews. STUDY DESIGN AND SETTING: We developed and piloted a framework for collaboration between a Cochrane Review Group (specializing in musculoskeletal injuries) and a Cochrane Field (focusing on health care of older people) for identifying, delivering, and disseminating priority Cochrane intervention reviews using hip fracture rehabilitation as an exemplar. The processes adopted included consultation of members of both the entities, mapping of trials from the Review Group's Specialized Register, jointly establishing criteria for topic prioritization, identification of researchers, and facilitating provision of expert peer review from the field. RESULTS: A framework for effective collaboration between a Cochrane Review Group and Cochrane Field for identifying and delivering priority Cochrane Reviews was devised and piloted. Additionally, two new Cochrane reviews, preceded by protocols, were published. CONCLUSION: The project demonstrated the feasibility and potential benefits of a structured collaboration between a Cochrane Review Group and a Cochrane Field for the identification and production of Cochrane reviews on priority topics.