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1.
Nature ; 571(7764): 193-197, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31189956

RESUMO

Research findings on the relationship between climate and conflict are diverse and contested. Here we assess the current understanding of the relationship between climate and conflict, based on the structured judgments of experts from diverse disciplines. These experts agree that climate has affected organized armed conflict within countries. However, other drivers, such as low socioeconomic development and low capabilities of the state, are judged to be substantially more influential, and the mechanisms of climate-conflict linkages remain a key uncertainty. Intensifying climate change is estimated to increase future risks of conflict.


Assuntos
Conflitos Armados/estatística & dados numéricos , Clima , Mudança Climática/estatística & dados numéricos , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Comportamento de Redução do Risco , Fatores Socioeconômicos , Incerteza
2.
Acta Orthop Belg ; 90(1): 83-89, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38669655

RESUMO

There is no consensus as to the optimal skeletal fixation method for Gustilo-Anderson IIIb fractures. External fixation methods have previously shown higher rates of superficial infection, whilst internal fixation has shown higher risk of deep infection, but lower risk of other complications. This paper investigates outcomes in open tibial fractures based on fixation method. A retrospective review was performed for patients presenting to an ortho-plastic unit with GA IIIb tibial fractures between June 2013 and October 2021. 85 patients were identified. The most common implant was an intramedullary nail (IMN), used in 29 patients (34.1%); open reduction and internal fixation (ORIF) was performed in 16 patients (18.8%). 18 patients (21.2%) were definitively managed with a frame alone. Mean follow-up from was 18 months (2-77). Patients with ORIF needed a mean of 3.37 operations; it was 2.48 for IMN which was significantly different from frames at 5.00 (p=0.000). The mean time to bony union after definitive fixation was 11.4 months. This differed depending on the implant used for fixation, with ORIF at 7.1 months, 10.1 for IMN, and frames at 17.2 months; ORIF significantly differed from frames (p=0.009). Superficial infection was common, seen in 38.8% of patients, and only 3 patients (4%) developed deep infections involving metalwork, with no difference in rates of either based on fixation method This study supports that ORIF has faster healing times, with less time to union compared to frames. It also shows that no implant was superior to another in terms of outcomes.


Assuntos
Fixação Interna de Fraturas , Fraturas Expostas , Fraturas da Tíbia , Humanos , Fraturas da Tíbia/cirurgia , Masculino , Feminino , Estudos Retrospectivos , Fraturas Expostas/cirurgia , Pessoa de Meia-Idade , Adulto , Idoso , Fixação Interna de Fraturas/métodos , Resultado do Tratamento , Adulto Jovem , Fixação Intramedular de Fraturas/métodos , Redução Aberta/métodos , Adolescente , Idoso de 80 Anos ou mais
3.
Proc Natl Acad Sci U S A ; 117(31): 18849-18857, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690691

RESUMO

One of the major events of early plant immune responses is a rapid influx of Ca2+ into the cytosol following pathogen recognition. Indeed, changes in cytosolic Ca2+ are recognized as ubiquitous elements of cellular signaling networks and are thought to encode stimulus-specific information in their duration, amplitude, and frequency. Despite the wealth of observations showing that the bacterial elicitor peptide flg22 triggers Ca2+ transients, there remain limited data defining the molecular identities of Ca2+ transporters involved in shaping the cellular Ca2+ dynamics during the triggering of the defense response network. However, the autoinhibited Ca2+-ATPase (ACA) pumps that act to expel Ca2+ from the cytosol have been linked to these events, with knockouts in the vacuolar members of this family showing hypersensitive lesion-mimic phenotypes. We have therefore explored how the two tonoplast-localized pumps, ACA4 and ACA11, impact flg22-dependent Ca2+ signaling and related defense responses. The double-knockout aca4/11 exhibited increased basal Ca2+ levels and Ca2+ signals of higher amplitude than wild-type plants. Both the aberrant Ca2+ dynamics and associated defense-related phenotypes could be suppressed by growing the aca4/11 seedlings at elevated temperatures. Relocalization of ACA8 from its normal cellular locale of the plasma membrane to the tonoplast also suppressed the aca4/11 phenotypes but not when a catalytically inactive mutant was used. These observations indicate that regulation of vacuolar Ca2+ sequestration is an integral component of plant immune signaling, but also that the action of tonoplast-localized Ca2+ pumps does not require specific regulatory elements not found in plasma membrane-localized pumps.


Assuntos
Proteínas de Arabidopsis , Sinalização do Cálcio/fisiologia , ATPases Transportadoras de Cálcio , Cálcio/metabolismo , Imunidade Vegetal/fisiologia , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , ATPases Transportadoras de Cálcio/genética , ATPases Transportadoras de Cálcio/metabolismo , Membrana Celular/metabolismo , Vacúolos/metabolismo
5.
J Chem Phys ; 142(21): 212425, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-26049445

RESUMO

The CO2ν3 asymmetric stretching mode is established as a vibrational chromophore for ultrafast two-dimensional infrared (2D-IR) spectroscopic studies of local structure and dynamics in ionic liquids, which are of interest for carbon capture applications. CO2 is dissolved in a series of 1-butyl-3-methylimidazolium-based ionic liquids ([C4C1im][X], where [X](-) is the anion from the series hexafluorophosphate (PF6 (-)), tetrafluoroborate (BF4 (-)), bis-(trifluoromethyl)sulfonylimide (Tf2N(-)), triflate (TfO(-)), trifluoroacetate (TFA(-)), dicyanamide (DCA(-)), and thiocyanate (SCN(-))). In the ionic liquids studied, the ν3 center frequency is sensitive to the local solvation environment and reports on the timescales for local structural relaxation. Density functional theory calculations predict charge transfer from the anion to the CO2 and from CO2 to the cation. The charge transfer drives geometrical distortion of CO2, which in turn changes the ν3 frequency. The observed structural relaxation timescales vary by up to an order of magnitude between ionic liquids. Shoulders in the 2D-IR spectra arise from anharmonic coupling of the ν2 and ν3 normal modes of CO2. Thermal fluctuations in the ν2 population stochastically modulate the ν3 frequency and generate dynamic cross-peaks. These timescales are attributed to the breakup of ion cages that create a well-defined local environment for CO2. The results suggest that the picosecond dynamics of CO2 are gated by local diffusion of anions and cations.

6.
Int J Sports Med ; 36(12): 968-73, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26212243

RESUMO

The long-term implications of making-weight daily on musculoskeletal health and functioning of the kidney and liver remain unknown. This study aimed to investigate musculoskeletal health and kidney and liver function in a group of retired jockeys. 28 retired male jockeys (age 50-70 years) provided fasting blood samples for markers of bone metabolism and kidney and liver function. A dual-energy x-ray absorptiometry (DXA) scan was performed for the assessment of bone mineral density (BMD). Established reference ranges were used for interpretation of results. Comparisons were made between retired jockeys based on the professional racing licence held: Flat, National Hunt or Dual. Mean whole-body osteopenia was reported, with no differences between groups. Bone markers, micronutrients, electrolytes and associated hormones, and markers for kidney and liver function were within clinical normative ranges. No differences existed between groups. Results indicate the retired jockeys in this study do not demonstrate compromised bone health or kidney and liver function. However, the retired jockeys may not have undergone chronic weight cycling in the extreme manner evident in present-day jockeys, indicating the next generation of jockeys may face more of a problem. Jockeys should be tracked longitudinally throughout their racing career and beyond.


Assuntos
Osso e Ossos/metabolismo , Rim/fisiologia , Fígado/fisiologia , Esportes/fisiologia , Redução de Peso , Idoso , Animais , Biomarcadores/sangue , Densidade Óssea , Ingestão de Energia/fisiologia , Cavalos , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Estudos Prospectivos
7.
Trauma Case Rep ; 51: 100997, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38577630

RESUMO

Nail gun injuries to the hand are an increasingly common encounter amongst those in the construction injury and a frequent presentation to the emergency department. Despite their frequency, nail gun injuries rarely involve significant structural injury. We present a rare case of severe injury by a barbed nail to the median nerve requiring surgical exploration. At our latest follow up 14 months post-operatively, the patient had ongoing sensory and motor deficits, cold intolerance and reduced proprioception and range of motion at the index finger. Continued hand therapy resulted in improved range of motion and desensitization. A systematic literature search has revealed no other reported cases of median nerve injury by nail gun.

8.
Int J Sports Med ; 34(8): 688-94, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23371826

RESUMO

Our aim was to use Peripheral Quantitative Computed Tomography (pQCT) to assess the bone health of male and female apprentice jockeys and age- and sex-matched peers. 2 groups of 25 young adults (n=50) (age range 15-38 years) were comprised of male and female apprentice jockeys, and male and female controls. We used pQCT to measure the distal tibia and distal radius. After covarying for weight and limb length, apprentice jockeys displayed less tibial cortical area and lower strength strain index at 14% distal shaft, 38% mid shaft and 66% proximal sites measured distally than controls (p=0.001). No between group differences were found in cortical density, trabecular area, and trabecular density at the tibia. Compared with controls, apprentice jockeys displayed greater trabecular density at the distal radial site (p=0.001), greater strength strain index at 66% proximal site measured distally (p=0.01), and a lower strength strain index at the distal radius (p=0.006). In conclusion, only trabecular density at the distal radius and strength strain index at the proximal radius were greater in apprentice jockeys than controls. Strategies to increase bone density and bone strength in apprentice jockeys should be considered by relevant industry stakeholders and their health providers.


Assuntos
Atletas , Densidade Óssea/fisiologia , Osso e Ossos/metabolismo , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Animais , Osso e Ossos/diagnóstico por imagem , Feminino , Cavalos , Humanos , Masculino , Rádio (Anatomia)/metabolismo , Esportes , Tíbia/metabolismo , Adulto Jovem
9.
Eur J Obstet Gynecol Reprod Biol ; 284: 20-23, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36924658

RESUMO

OBJECTIVE: Serum Anti-Müllerian Hormone (AMH) levels have been shown to be lower among women who have experienced recurrent pregnancy loss (RPL) compared with the general population. However, it is unclear whether it can predict livebirth. This study aims to determine whether AMH can predict the likelihood of a livebirth in women with RPL. STUDY DESIGN: Prospective analysis of a consecutive cohort of women undergoing investigation for RPL in a tertiary referral centre over a seven year period (August 2014 -December 2021). Analysis was performed using descriptive statistics, chi-square models and logistic regression models adjusting for maternal age and previous livebirth. Exclusion criteria for the regression analysis included abnormal parental karyotype and abnormal pelvic ultrasound scan. Pregnancy outcome was defined as livebirth or further pregnancy loss. RESULTS: There were 488 women who underwent investigation of RPL during the study period. Of these, 65.2% (n = 318) conceived following attendance at the clinic. The majority of these women (69.4%, n = 221) proceeded to have a livebirth. There were no differences in median AMH levels between the livebirth group and the further pregnancy loss group (11 pmol/L vs 9 pmol/L respectively (p = 0.083). AMH did not affect clinical pregnancy rates (p = 0.77, 95% CI = 0.99 [0.98, 1.01]) or pregnancy outcome (p = 0.30, 95% CI = 1.01 [0.99, 1.04]). Abnormal pelvic ultrasonography (p = 0.04) and an abnormal parental karyotype (p = 0.04) were associated with an increased likelihood of a subsequent pregnancy loss. CONCLUSION: Although AMH levels may have some utility in counselling of some couples with RPL, these contemporaneous data indicate that low AMH does not negatively influence subsequent pregnancy outcome in women with recurrent pregnancy loss.


Assuntos
Aborto Habitual , Resultado da Gravidez , Gravidez , Feminino , Humanos , Hormônio Antimülleriano , Idade Materna , Taxa de Gravidez , Aborto Habitual/epidemiologia
10.
Pilot Feasibility Stud ; 9(1): 193, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012747

RESUMO

BACKGROUND: Child criminal exploitation is a form of child abuse that poses a serious risk to the welfare, safety, and wellbeing of young people. Multisystemic therapy (MST) is an intensive family and community-based intervention for young people with anti-social behavioral problems, many of whom will be at risk of criminal exploitation. This protocol describes a pilot feasibility study and process evaluation, designed to examine MST for children at risk of criminal exploitation. METHODS: This pilot feasibility study and process evaluation involves two phases with associated subphases: phase 1.1 involved the collaborative refinement of the logic model adapting MST for children at risk of criminal exploitation; phase 1.2 involved pre-pilot interviews with MST therapists, families, and young people; phase 2.1 is a pilot modeling study of MST for children at risk of criminal exploitation, and; Phase 2.2 is a process evaluation that will involve interviewing stakeholders, MST therapists and employees, families, and young people. The dataset for the process evaluation will include questionnaires completed by parents and young people at baseline, mid-treatment, end of treatment, and 6 months after treatment. We will supplement these data with participant-level data linkage from MST sites and services. RESULTS: Accrual to the pilot stage of this project opened on 6th August 2021 and is due to close on 31st May 2022. We aim to publish the results of this feasibility study and process evaluation in 2023. CONCLUSIONS: The results of this feasibility study and process evaluation will inform the decision as to whether it is advisable to progress to a pilot clinical trial of MST for children at risk of criminal exploitation. TRIAL REGISTRATION: Trial registration: ISRCTN registry, ISRCTN16164816 on 25th January 2021- https://doi.org/10.1186/ISRCTN16164816 .

12.
Neurology ; 99(8): e858-e864, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35618436

RESUMO

BACKGROUND AND OBJECTIVES: We aimed to identify how child neurology and neurodevelopmental disabilities residency program directors (PDs) implemented revised Accreditation Council for Graduate Medical Education requirements for adult neurology training for child neurology residents. Before 2014, the American Board of Psychiatry and Neurology certification for child neurology required an adult year, with no specified rotation requirements. At that point, programs scheduled a median of 10 months of adult neurology rotations during the third postgraduate year (PGY-3). In 2014, the adult neurology requirements were modified to include 6 months of hospital-based, 3 months of outpatient, and 3 months of other elective (may include neurophysiology, neuropathology, and/or neuroradiology) rotations. However, the effects of these changes on child neurology residency training nationally have not been characterized. METHODS: A 16-item online survey was emailed to 79 PDs in the United States in September 2020. Survey responses were collected from September to October 2020. Descriptive statistics were calculated, and associations with departmental affiliation (pediatrics/neurology), graduate medical education (GME) funding source, and program size were compared using nonparametric tests. RESULTS: The response rate was 72% (53 pediatric neurology, 3 neurodevelopmental disabilities). The median adult months per year of training were as follows: 9 PGY-3, 2 PGY-4, and 1 PGY-5. Nearly all had both hospital inpatient and consult rotations with night and/or weekend shifts; 57% included neurocritical care and 36% epilepsy monitoring units. 48% of programs scheduled night and weekend shifts (including 25% that scheduled 24-hour calls) for residents on outpatient and elective rotations. Few programs required adult neurophysiology (20%), neuropathology (32%), or neuroradiology (25%). Programs with children's hospital GME funding (for either 2 or 3 years) tended to be larger (p = 0.008). Otherwise, departmental affiliation, funding source, and program size were not associated with rotation timing. DISCUSSION: Most child neurology residency programs still consolidate adult training in the PGY-3 year and often schedule additional hospital shifts during outpatient and elective months. However, there is a small shift toward adult neurology rotations occurring in the PGY-4 and PGY-5. Departmental affiliation, funding source, and program size do not consistently affect training practices. Few programs mandate adult neurophysiology, neuropathology, or neuroradiology rotations.


Assuntos
Internato e Residência , Neurologia , Acreditação , Adulto , Criança , Educação de Pós-Graduação em Medicina , Humanos , Neurologia/educação , Inquéritos e Questionários , Estados Unidos
13.
Pediatr Neurol ; 133: 34-39, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35753147

RESUMO

BACKGROUND: In 2014 the Accreditation Council for Graduate Medical Education modified adult training requirements for child neurology certification to reduce the number of hospital-based rotations and require inclusion of outpatient clinic and electives. We aimed to identify how these training requirements are being met and explored its impact on residents. METHODS: A REDCap questionnaire surveying resident opinion on impact of adult training on resident education, professional development, and wellness was e-mailed to 79 program directors in the United States for distribution in 2020. Results were analyzed using descriptive statistics and t test calculations. Qualitative analysis of narrative responses involved theme identification. RESULTS: A total of 116 child neurology residents participated (30.2% PGY-3, 37.9% PGY-4, and 31.9% PGY-5 residents); 20.9% had all adult rotations during the PGY-3 year, and 79.1% had adult rotations spread throughout residency. Adult training had a small positive impact on resident autonomy and a negative impact on resident wellness regardless of training structure. However, residents with 12 months of adult training during PGY-3 year scored worse on burnout, mood changes, work-life balance, and social well-being (P < 0.05). Some themes identified included residents feeling unsafe due to lack of supervision, that education was not prioritized, and that adult patient care lacked relevance to long-term career goals. CONCLUSIONS: Adult neurology training was found to negatively affect child neurology resident wellness, with a larger negative impact when adult training was completed in 12 months during PGY-3 year. Other identified areas where change could be implemented include improving feelings of resident safety and prioritizing quality and relevance of education.


Assuntos
Internato e Residência , Neurologia , Acreditação , Adulto , Criança , Currículo , Educação de Pós-Graduação em Medicina , Humanos , Neurologia/educação , Inquéritos e Questionários , Estados Unidos
14.
Methods Mol Biol ; 2368: 81-94, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34647250

RESUMO

Despite mechanical stimulation having profound effects on plant growth and development and modulating responses to many other stimuli, including to gravity, much of the molecular machinery triggering plant mechanical responses remains unknown. This gap in our knowledge arises in part from difficulties in applying reproducible, long-term touch stimulation to plants. We describe the design and implementation of the Automated Botanical Contact Device (ABCD) that applies intermittent, controlled, and highly reproducible mechanical stimulation by drawing a plastic sheet across experimental plants. The device uses a computer numerical control platform and continuously monitors plant growth and development using automated computer vision and image analysis. The system is designed around an open-source architecture to help promote the generation of comparable datasets between laboratories. The ABCD also offers a scalable system that could be deployed in the controlled environment setting, such as a greenhouse, to manipulate plant growth and development through controlled, repetitive mechanostimulation.


Assuntos
Plantas , Tato , Gravitação , Desenvolvimento Vegetal
15.
Phys Sportsmed ; 49(2): 207-213, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32777964

RESUMO

OBJECTIVE: Jockeys compete in a sport, horseracing, renowned for its physical and psychological demands. Previous research has identified that common mental disorders (CMDs) may be prevalent among this unique population of athletes. The aim of the present study was to further explore the prevalence of CMDs among jockeys and to test for associations with potential risk factors. METHODS: An anonymous survey was distributed to professional jockey online. Self-report screening tools for four CMDs (psychological distress, depression, generalized anxiety, and adverse alcohol use) were included alongside predictor variables from questionnaires assessing for burnout, career satisfaction, social support, and the contemplation of retirement. Binary logistic regression was used to explore associations between CMDs (present versus not present) and risk factors. Eighty-four professional jockeys completed the questionnaire (response rate = 52%). RESULTS: In total, 79% of jockeys met the threshold for at least one CMD. Prevalence (%) of CMD varied as follows: adverse alcohol (61%), depression (35%), generalized anxiety (27%), and psychological distress (19%). Burnout, career (dis)satisfaction, lower levels of social support, and the contemplation of retirement increased the odds of meeting the criteria for CMDs. CONCLUSION: The findings indicate that jockeys report CMD symptoms at comparable rates to athletes in other sports. The study was the first to highlight potential risk factors as predictors of CMDs among jockeys, including burnout, career satisfaction, and the current contemplation of retirement. Screening tools for the risk factors demonstrated may, therefore, provide useful in the early identification of CMDs among jockeys. The development of jockey-specific assessment tools, education programmes, and interventions may help better understand and support the mental health of jockeys.


Assuntos
Depressão , Transtornos Mentais , Estudos Transversais , Humanos , Transtornos Mentais/epidemiologia , Prevalência , Fatores de Risco
16.
J Interv Card Electrophysiol ; 60(1): 49-56, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31997041

RESUMO

PURPOSE: Catheter ablation for supraventricular tachycardia (SVT) in adults with congenital heart disease (ACHD) is an important therapeutic option. Cavo-tricuspid isthmus (CTI)-dependent intraatrial re-entrant tachycardia (IART) is common. However, induction of sustained tachycardia at the time of ablation is not always possible. We hypothesised that performing an empiric CTI line in case of non-inducibility leads to good outcomes. Long-term outcomes of empiric versus entrained CTI ablation in ACHD patients were examined. METHODS: Retrospective, single-centre, case-control study over 7 years. Arrhythmia-free survival after empiric versus entrained CTI ablation was compared. RESULTS: Eighty-seven CTI ablations were performed in 85 ACHD patients between 2010 and 2017. The mean age of the cohort was 43 years and 48% were male. Underlying aetiology included ASD (31%), VSD (11.4%), AVSD (9.1%), AVR (4.8%), Fallot's (18.4%), Ebstein's (2.3%), Fontan's palliation (9.2%) and atrial switch (13.8%). CTI-dependent IART was entrained in 59 patients whereas it was non-inducible in 28. The latter had an empiric CTI ablation. Forty-three percent of procedures were performed under general anaesthesia. There were no reported procedural complications. There was no significant difference in the mean procedure or fluoroscopy times between the groups (empiric vs entrained CTI; 169.1 vs 183.3 and 28.1 vs 19.9 min). Arrhythmia-free survival was 64.3% versus 72.8% (p value 0.44) in the empiric and entrained groups at 21 months follow-up. CONCLUSIONS: Long-term outcomes after empiric and entrained CTI ablation for IART in ACHD patients are comparable. This is a safe and effective therapeutic option. In the case of non-inducibility of IART, an empiric CTI line should be considered in this cohort.


Assuntos
Ablação por Cateter , Cardiopatias Congênitas , Adulto , Flutter Atrial/diagnóstico por imagem , Flutter Atrial/cirurgia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Estudos Retrospectivos , Taquicardia , Resultado do Tratamento
17.
J Exp Med ; 158(6): 1979-92, 1983 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-6580373

RESUMO

In this report, we describe a previously unidentified component in the murine Ia antigen complex. SDS-PAGE analysis of anti-Ia immunoprecipitates prepared from spleen cells biosynthetically labeled with 35S-sulfate showed no detectable incorporation of 35SO4 into alpha, beta, or Ii chains but did not reveal the presence of a novel sulfate-bearing molecule of considerable molecular weight heterogeneity (46-69-kdaltons). The 46-69-kdalton molecule could be precipitated with monoclonal antibodies specific for I-A, I-E, and Ii glycoproteins but was not seen in control precipitates, nor in association with IgG or class I MHC molecules. Preliminary biochemical characterization indicated that the 46-69-kdalton product is extremely polydisperse, both in charge and apparent molecular weight, is sensitive to proteases, and bears the sulfate moiety on a large pronase-resistant structure. These results suggested this component might be a proteoglycan. Definitive identification of this component as a proteoglycan was accomplished by selective enzymatic degradation experiments which showed that the sulfate-bearing component of the 46-69-kdalton molecule is chondroitin 6-sulfate.


Assuntos
Antígenos de Histocompatibilidade Classe II/análise , Animais , Precipitação Química , Eletroforese em Gel de Poliacrilamida , Camundongos , Peso Molecular , Sulfatos/metabolismo
18.
J Exp Med ; 145(2): 438-42, 1977 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-64585

RESUMO

Anti-H-2 reagents have been tested on solubilized spleen cell preparations in combinations expected to be specific for D region products. Two different types of molecules were detected. One showed the expected reactivity with both antisera to private and antisera to public specificities. However, an additional molecule was detected which reacted only with antisera to public specificities. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis migration patterns indicated that both products have a similar molecular size of approximately 45,000 daltons. The data therefore present chemical evidence for the existence of a third H-2-associated gene product of 45,000 mol wt in addition to the classical H-2K and H-2D antigens.


Assuntos
Genes , Ligação Genética , Antígenos de Histocompatibilidade , Animais , Epitopos , Antígenos de Histocompatibilidade/análise , Isoanticorpos , Camundongos , Camundongos Endogâmicos , Peso Molecular , Baço/imunologia
19.
J Exp Med ; 145(6): 1550-8, 1977 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-68094

RESUMO

Sequential precipitations of soluble BALB/c antigen with antisera detecting private and public H-2 specificities indicated three distinct classes of molecules of 45,000 mol wt. However, only two of these classes of molecules were detectable in antigen from the loss mutant, BALB/c-H-2db. The class of molecules, detectable in the wild-type strain but missing in the mutant, does not bear private specificities but does react with an antiserum detecting H-2 public specificities. Absorption in mutant mice of the antiserum to public specificities, left antibodies specific for the antigen detectable in BALB/c but not BALB/c-H-2db. Genetic mapping studies using this specific antiserum indicated that the antigenic loss of this mutant is in a gene which maps in or close to the H-2D region, separable from the H-2K, S, G, Qa-2, and Tla regions.


Assuntos
Genes , Antígenos de Histocompatibilidade , Mutação , Animais , Mapeamento Cromossômico , Eletroforese em Gel de Poliacrilamida , Epitopos , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Modelos Biológicos , Solubilidade
20.
J Exp Med ; 162(6): 1916-34, 1985 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-3864916

RESUMO

The murine Ia-associated chondroitin sulfate proteoglycan (CSPG) was studied both biochemically and immunochemically to determine the nature of its core protein. Chondroitinase ABC or chondroitinase AC treatment of the CSPG digested the chondroitin sulfate glycosaminoglycan, yielding a core protein that migrated with an apparent molecular weight of 38,000. Comparative V8 protease digestion of the CSPG core protein and conventional invariant glycoproteins yielded homologous peptides, indicating that the core protein and invariant chain were structurally similar. The purified CSPG and its core protein were both shown to react directly with the monoclonal anti-invariant chain antibody, In-1. Comparative tryptic peptide analysis by high performance liquid chromatography demonstrated coelution of the majority of the peptides from the invariant chain and the CSPG core protein. Collectively, these results indicate that the CSPG is an alternatively processed form of invariant chain.


Assuntos
Proteoglicanas de Sulfatos de Condroitina/análise , Antígenos de Histocompatibilidade Classe II/análise , Proteoglicanas/análise , Animais , Anticorpos Monoclonais , Especificidade de Anticorpos , Autorradiografia , Proteoglicanas de Sulfatos de Condroitina/genética , Proteoglicanas de Sulfatos de Condroitina/imunologia , Eletroforese em Gel de Poliacrilamida , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Camundongos , Camundongos Endogâmicos , Peso Molecular , Peptídeos/análise , Testes de Precipitina , Baço/citologia
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