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1.
Public Health Nutr ; 23(8): 1334-1339, 2020 06.
Article in English | MEDLINE | ID: mdl-32157977

ABSTRACT

OBJECTIVE: When breast-feeding is not possible, commercially made human milk substitute is recommended. Some consumers would prefer to make their own homemade infant formula (HIF) and may seek information on this practice from internet sources. The purpose of the current study was to investigate the content of blogs posting HIF recipes. DESIGN: Blog postings were identified through a comprehensive search conducted using the Google search engine and the following search terms along with the term 'blog': 'Make Your Own Baby Formula', 'Homemade Baby Formula', 'Do It Yourself (DIY) Baby Formula', 'DIY Baby Formula', 'Baby Formula Recipe' and 'All Natural Baby Formula'. A quantitative content analysis of blogs offering recipes for HIF was completed. Blogs that met the inclusion criteria were reviewed for disclaimers, blogger's credentials, rationale for HIF use, advertisement or sale of recipe ingredients and recipe ingredients. SETTING: Worldwide Web. RESULTS: Fifty-nine blogs, featuring one hundred forty-four recipes, met inclusion criteria. Among reviewed blogs, 33·9 % did not provide a disclaimer stating breast milk is the preferred option, 25·4 % recommended consulting a healthcare professional before using, and 76·3 % and 20·3 % either advertised or sold ingredients or recipe kits, respectively. Credentials of bloggers varied and only seven bloggers identified themselves as 'nutritionists'. The three most frequently mentioned recipe ingredients were whole raw cow's milk (24·3 %), raw goat's milk (23·6 %) and liver (14·5 %). CONCLUSIONS: Clinicians should be aware of this trend, discuss source of formula with parents, advocate for appropriate infant feeding practices and monitor for side effects.


Subject(s)
Infant Formula , Milk, Human , Infant , Female , Animals , Cattle , Humans , Breast Feeding , Feeding Behavior
2.
Phys Rev Lett ; 121(14): 145502, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-30339414

ABSTRACT

Despite numerous theoretical models and simulation results, a clear physical picture of dislocations traveling at velocities comparable to the speed of sound in the medium remains elusive. Using two complementary atomistic methods to model uniformly moving screw dislocations, lattice dynamics and molecular dynamics, the existence of mechanical instabilities in the system is shown. These instabilities are found at material-dependent velocities far below the speed of sound. We show that these are the onset of an atomistic kinematic generation mechanism, which ultimately results in an avalanche of further dislocations. This homogeneous nucleation mechanism, observed but never fully explained before, is relevant in moderate and high strain rate phenomena including adiabatic shear banding, dynamic fracture, and shock loading. In principle, these mechanical instabilities do not prevent supersonic motion of dislocations.

3.
Phys Chem Chem Phys ; 20(35): 23085-23094, 2018 Sep 12.
Article in English | MEDLINE | ID: mdl-30167620

ABSTRACT

Coarse-grained molecular dynamics simulations are used to elucidate molecular mechanisms responsible for different mechanical behaviours of elastomers containing spherical particles with different volume fractions. We observe that different filler volume fractions result in qualitatively different responses of the polymer nanocomposite to tensile strain. At relatively low filler volume fraction a yield drop appears in the stress-strain curve. As the filler volume fraction increases there is a reduction in the rate of plastic hardening, becoming plastic softening at sufficiently high filler volume fraction. We demonstrate that these behaviours are a result of the network formed by the polymer chains and filler particles. We identify three distinct molecular structural motifs between polymer and filler particles whose relative prevalence varies with the filler volume fraction and as the system is dynamically strained. We show how this evolution in molecular structure is directly linked to the observed mechanical response.

4.
Br J Surg ; 104(1): 98-107, 2017 01.
Article in English | MEDLINE | ID: mdl-27762448

ABSTRACT

BACKGROUND: The optimal timing of cholecystectomy for patients admitted with acute gallbladder pathology is unclear. Some studies have shown that emergency cholecystectomy during the index admission can reduce length of hospital stay with similar rates of conversion to open surgery, complications and mortality compared with a 'delayed' operation following discharge. Others have reported that cholecystectomy during the index acute admission results in higher morbidity, extended length of stay and increased costs. This study examined the cost-effectiveness of emergency versus delayed cholecystectomy for acute benign gallbladder disease. METHODS: Using data from a prospective population-based cohort study examining the outcomes of cholecystectomy in the UK and Ireland, a model-based cost-utility analysis was conducted from the perspective of the UK National Health Service, with a 1-year time horizon for costs and outcomes. Probabilistic sensitivity analysis was used to investigate the impact of parameter uncertainty on the results obtained from the model. RESULTS: Emergency cholecystectomy was found to be less costly (£4570 versus £4720; €5484 versus €5664) and more effective (0·8868 versus 0·8662 QALYs) than delayed cholecystectomy. Probabilistic sensitivity analysis showed that the emergency strategy is more than 60 per cent likely to be cost-effective across willingness-to-pay values for the QALY from £0 to £100 000 (€0-120 000). CONCLUSION: Emergency cholecystectomy is less costly and more effective than delayed cholecystectomy. This approach is likely to be beneficial to patients in terms of improved health outcomes and to the healthcare provider owing to the reduced costs.


Subject(s)
Cholecystectomy, Laparoscopic/economics , Cholecystitis, Acute/economics , Cholecystitis, Acute/surgery , Emergencies , Cost-Benefit Analysis , Humans , Models, Economic , Quality-Adjusted Life Years , State Medicine/economics , Time-to-Treatment , United Kingdom
5.
Br J Surg ; 102(4): 388-98, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25624168

ABSTRACT

BACKGROUND: Surgical resection of colorectal liver metastases (CRLMs) is the standard of care when possible, although this strategy has not been compared with non-operative interventions in controlled trials. Although survival outcomes are clear, the cost-effectiveness of surgery is not. This study aimed to estimate the cost-effectiveness of resection for CRLMs compared with non-operative treatment (palliative care including chemotherapy). METHODS: Operative and non-operative cohorts were identified from a prospectively maintained database. Patients in the operative cohort had a minimum of 10 years of follow-up. A model-based cost-utility analysis was conducted to quantify the mean cost and quality-adjusted life-years (QALYs) over a lifetime time horizon. The analysis was conducted from a healthcare provider perspective (UK National Health Service) in a secondary care (hospital) setting. RESULTS: Median survival was 41 and 21 months in the operative and non-operative cohorts respectively (P < 0·001). The operative strategy dominated non-operative treatments, being less costly (€22,200 versus €32,800) and more effective (4·017 versus 1·111 QALYs gained). The results of extensive sensitivity analysis showed that the operative strategy dominated non-operative treatment in every scenario. CONCLUSION: Operative treatment of CRLMs yields greater survival than non-operative treatment, and is both more effective and less costly.


Subject(s)
Colorectal Neoplasms , Liver Neoplasms/economics , Aged , Antineoplastic Combined Chemotherapy Protocols/economics , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Female , Humans , Liver Neoplasms/secondary , Liver Neoplasms/therapy , Male , Markov Chains , Metastasectomy/economics , Middle Aged , Palliative Care/economics , Prospective Studies , Quality-Adjusted Life Years , Survival Analysis , Treatment Outcome
6.
Br J Cancer ; 110(12): 2837-46, 2014 Jun 10.
Article in English | MEDLINE | ID: mdl-24867697

ABSTRACT

BACKGROUND: The purpose of this study was to determine the accuracy of sentinel lymph node (SLN) biopsy with technetium 99 (99mTc) and/or blue dye-enhanced lymphoscintigraphy in vulval cancer. METHODS: Sensitive searches of databases were performed upto October 2013. Studies with at least 75% of women with FIGO stage IB or II vulval cancer evaluating SLN biopsy with 99mTc, blue dye or both with reference standard of inguinofemoral lymphadenectomy (IFL) or clinical follow-up were included. Meta-analyses were performed using Meta-Disc version 1.4. RESULTS: Of the 2950 references, 29 studies (1779 women) were included; most of them evaluated 99mTc combined with blue dye. Of these, 24 studies reported results for SLN followed by IFL, and 5 reported clinical follow-up only for SLN negatives. Pooling of all studies was inappropriate because of heterogeneity. Mean SLN detection rates were 94.0% for 99mTc, 68.7% for blue dye and 97.7% for both. SLN biopsy had pooled sensitivity of 95% (95% CI 92-98%) with negative predictive value (NPV) of 97.9% in studies using 99mTc/blue dye, ultrastaging and immunohistochemistry with IFL as reference. Pooled sensitivity for SLN with clinical follow-up for SLN-negatives was 91% (85-95%) with NPV 95.6%. Patients undergoing SLN biopsy experienced less morbidity than those undergoing IFL. CONCLUSIONS: Sentinel lymph node biopsy using 99mTC, blue dye and ultrastaging with immunohistochemistry is highly accurate when restricted to carefully selected patients, within a rigorous protocol, with close follow-up and where sufficient numbers for learning curve optimisation exist. Patients must make an informed choice between the slightly higher groin recurrence rates of SLN biopsy vs the greater morbidity of IFL.


Subject(s)
Lymph Nodes/pathology , Sentinel Lymph Node Biopsy , Vulvar Neoplasms/pathology , Coloring Agents , Early Detection of Cancer , Female , Humans , Immunohistochemistry , Lymph Nodes/diagnostic imaging , Lymph Nodes/surgery , Lymphatic Metastasis , Lymphoscintigraphy , Neoplasm Recurrence, Local , Radiopharmaceuticals , Staining and Labeling , Technetium , Vulvar Neoplasms/diagnostic imaging
7.
Phys Rev Lett ; 113(21): 215501, 2014 Nov 21.
Article in English | MEDLINE | ID: mdl-25479502

ABSTRACT

Highly mobile crystal defects such as crowdions and prismatic dislocation loops exhibit an anomalous temperature independent mobility unexplained by phonon scattering analysis. Using a projection operator, without recourse to elasticity, we derive analytic expressions for the mobility of highly mobile defects and dislocations which may be efficiently evaluated in molecular dynamics simulation. The theory explains how a temperature-independent mobility arises because defect motion is not an eigenmode of the Hessian, an implicit assumption in all previous treatments.

8.
Inj Prev ; 20(5): e11, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24842981

ABSTRACT

BACKGROUND: Scalds are one of the most common forms of thermal injury in young children worldwide. Childhood scald injuries, which mostly occur in the home, result in substantial health service use and considerable morbidity and mortality. There is little research on effective interventions to prevent scald injuries in young children. OBJECTIVES: To determine the relationship between a range of modifiable risk factors for medically attended scalds in children under the age of 5 years. DESIGN: A multicentre case-control study in UK hospitals and minor injury units with parallel home observation to validate parental reported exposures. Cases will be 0-4 years old with a medically attended scald injury which occurred in their home or garden, matched on gender and age with community controls. An additional control group will comprise unmatched hospital controls drawn from children aged 0-4 years attending the same hospitals and minor injury units for other types of injury. Conditional logistic regression will be used for the analysis of cases and matched controls, and unconditional logistic regression for the analysis of cases and unmatched controls to estimate ORs and 95% CI, adjusted and unadjusted for confounding variables. MAIN EXPOSURE MEASURES: Use of safety equipment and safety practices for scald prevention and scald hazards. DISCUSSION: This large case-control study will investigate modifiable risk factors for scalds injuries, adjust for potential confounders and validate measures of exposure. Its findings will enhance the evidence base for prevention of scalds injuries in young children.


Subject(s)
Accident Prevention/methods , Accidents, Home/prevention & control , Burns/prevention & control , Safety , Burns/etiology , Case-Control Studies , Child, Preschool , Female , Humans , Infant , Logistic Models , Male , Odds Ratio , Risk Factors , Safety/standards , United Kingdom
9.
Plast Reconstr Surg ; 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38548710

ABSTRACT

INTRODUCTION: Numerous complications are reported following interventions for Dupuytren's contracture; however, their incidence, management, and outcomes remain poorly reported. The aims of this review were to report the proportions of complications, compare likelihood of complications between interventions, and evaluate reporting of complications, including assessment, grading, management, and subsequent reporting of their impact on patient outcomes. METHODS: Extracted data included patient demographics, intervention details, complications, their management, and final outcomes. Analysis of descriptive data enabled review of complications reporting. Meta-analysis(MA) of non-comparative datasets enabled estimation of proportions of patients experiencing complications. Network meta-analysis(NMA) of comparative studies estimated the relative occurrence of complications between interventions. Risk of bias analysis was performed. RESULTS: 26 studies, comprising 10,831 patients, were included. Interventions included collagenase injection, percutaneous needle fasciotomy(PNF), limited fasciectomy(LF), open fasciotomy(OF), and dermofasciectomy(DF). Overall quality and consistency of outcomes reporting was poor. MA enabled estimates of probabilities for three common complications(infection, nerve injury, complex regional pain syndrome(CRPS)) across all interventions; the reported rates for LF were 4.5% for infection, 3% for nerve injury, and 3.3% for CRPS. As the commonest intervention, LF was used as the reference intervention for comparison of the commonest complications via NMA, including haematoma [OF OR 0.450(0.277, 0.695); PNF OR 0.245(0.114, 0.457)], infection [PNF OR 0.2(0.0287, 0.690); DF OR 2.02(1.02, 3.74)], and neuropraxia [PNF OR 0.0926(0.00553, 0.737)]. We noted that the complication incidence was higher the more invasive the intervention. CONCLUSIONS: There was limited reporting of complication occurrence, management, and outcomes following interventions, contributing to a gap in information for informed patient consent. MA was possible for reporting of proportions for infection, nerve injury, and CRPS across interventions. NMA enabled direct comparison of the six commonest complications between interventions. These findings can guide intervention selection. Improving consistency and quality in complications reporting is essential to aid counselling of patients regarding the true rates and consequences of the risks of interventions. TYPE OF STUDY/LEVEL OF EVIDENCE: 2.

10.
Br J Cancer ; 109(10): 2533-47, 2013 Nov 12.
Article in English | MEDLINE | ID: mdl-24129233

ABSTRACT

BACKGROUND: This study examines the cost-effectiveness of sentinel lymph node biopsy, a potentially less morbid procedure, compared with inguinofemoral lymphadenectomy (IFL) among women with stage I and stage II vulval squamous cell carcinoma. METHODS: A model-based economic evaluation was undertaken based on clinical evidence from a systematic review of published sources. A decision tree model was developed with the structure being informed by clinical input, taking the perspective of the health-care provider. RESULTS: For overall survival for 2 years, IFL was found to be the most cost-effective option and dominated all other strategies, being the least costly and most effective. For morbidity-free related outcomes for 2 years, sentinel lymph node (SLN) biopsy with 99mTc and blue dye and haematoxylin & eosin (H&E) histopathology, with ultrastaging and immunohistochemistry reserved for those that test negative following H&E is likely to be the most effective approach. CONCLUSION: SLN biopsy using 99mTc and blue dye with ultrastaging may be considered the most cost-effective strategy based on the outcome of survival free of morbidity for 2 years. The findings here also indicate that using blue dye and H&E for the identification of the SLN and the identification of metastasis, respectively, are not sensitive enough to be used on their own.


Subject(s)
Carcinoma, Squamous Cell/pathology , Lymph Node Excision/economics , Sentinel Lymph Node Biopsy/economics , Vulvar Neoplasms/pathology , Carcinoma, Squamous Cell/mortality , Cost-Benefit Analysis , Female , Health Care Costs , Humans , Inguinal Canal , Lymph Nodes/pathology , Lymphatic Metastasis , Vulvar Neoplasms/mortality
11.
Osteoarthritis Cartilage ; 21(9): 1290-8, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23973143

ABSTRACT

OBJECTIVE: To compare the effectiveness of acupuncture with other relevant physical treatments for alleviating pain due to knee osteoarthritis. DESIGN: Systematic review with network meta-analysis, to allow comparison of treatments within a coherent framework. Comprehensive searches were undertaken up to January 2013 to identify randomised controlled trials in patients with osteoarthritis of the knee, which reported pain. RESULTS: Of 156 eligible studies, 114 trials (covering 22 treatments and 9,709 patients) provided data suitable for analysis. Most trials studied short-term effects and many were classed as being of poor quality with high risk of bias, commonly associated with lack of blinding (which was sometimes impossible to achieve). End of treatment results showed that eight interventions: interferential therapy, acupuncture, TENS, pulsed electrical stimulation, balneotherapy, aerobic exercise, sham acupuncture, and muscle-strengthening exercise produced a statistically significant reduction in pain when compared with standard care. In a sensitivity analysis of satisfactory and good quality studies, most studies were of acupuncture (11 trials) or muscle-strengthening exercise (9 trials); both interventions were statistically significantly better than standard care, with acupuncture being statistically significantly better than muscle-strengthening exercise (standardised mean difference: 0.49, 95% credible interval 0.00-0.98). CONCLUSIONS: As a summary of the current available research, the network meta-analysis results indicate that acupuncture can be considered as one of the more effective physical treatments for alleviating osteoarthritis knee pain in the short-term. However, much of the evidence in this area of research is of poor quality, meaning there is uncertainty about the efficacy of many physical treatments.


Subject(s)
Acupuncture Analgesia/methods , Arthralgia/therapy , Osteoarthritis, Knee/therapy , Physical Therapy Modalities , Arthralgia/etiology , Humans , Osteoarthritis, Knee/complications , Randomized Controlled Trials as Topic
12.
Angiogenesis ; 15(4): 727-44, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22752444

ABSTRACT

Atherosclerosis involves angiogenesis and inflammation with the ability of endothelial cells and monocytes to respond to chemokines. We addressed here by in vitro and in vivo approaches, the role of the chemokine Regulated on Activation, Normal T Cell Expressed and Secreted (RANTES)/CCL5 on angiogenesis through its receptors CCR1, CCR5, syndecan-1 (SDC-1), syndecan-4 (SDC-4) and CD-44. Our data demonstrate that RANTES/CCL5 is pro-angiogenic in a rat subcutaneous model. This RANTES/CCL5-activity may be related to the in vitro promotion of endothelial cell migration, spreading and neo-vessel formation. RANTES/CCL5-mediated angiogenesis depends at least partly on Vascular Endothelial Growth Factor (VEGF) secretion by endothelial cells, since this effect is decreased when endothelial cells are incubated with anti-VEGF receptor antibodies. RANTES/CCL5-induced chemotaxis is mediated by matrix metalloproteinase-9. We demonstrate that specific receptors of RANTES/CCL5 such as G protein-coupled receptors CCR1 and CCR5, and heparan sulfate proteoglycans, SDC-1, SDC-4 or CD-44, play a major role in RANTES/CCL5-induced angiogenic effects. By the use of two RANTES/CCL5 mutants, [E66A]-RANTES/CCL5 with impaired ability to oligomerize, and [44AANA47]-RANTES/CCL5 mutated in the main RANTES/CCL5-glycosaminoglycan (GAG) binding site, we demonstrate that chemokine oligomerization and binding to GAGs are essential in RANTES/CCL5-induced angiogenic effects. According to these results, new therapeutic strategies based on RANTES/CCL5 can be proposed for neo-angiogenesis after vascular injury. Mutants of RANTES/CCL5 may also represent an innovative approach to prevent the angiogenesis associated with the formation of atherosclerotic plaque.


Subject(s)
Chemokine CCL5/physiology , Glycosaminoglycans/physiology , Neovascularization, Physiologic/physiology , Receptors, CCR1/physiology , Animals , Enzyme-Linked Immunosorbent Assay , Immunohistochemistry , Male , Rats , Rats, Wistar
13.
Epidemiol Infect ; 140(12): 2190-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22459739

ABSTRACT

Glasgow (Scotland's largest city) has a high prevalence of injecting drug use and has one of the highest prevalences of hepatitis C virus (HCV) infection in injecting drug users (IDUs) in Western Europe. HCV prevalence data from surveys of Glasgow's IDUs from 1990 to 2007 were utilized and a model was applied that described the prevalence of HCV as a function of the rate (force) of infection. Force-of-infection estimates for HCV that may vary over time and injecting career length over a range of variables were investigated. New initiates to injecting were found to be at increased risk of HCV infection, with being recruited from a street location and reporting injecting in prison leading to a significant increase in the risk of infection in new initiates. These results indicate areas of importance for the planning of public health measures that target the IDU population.


Subject(s)
Hepatitis C/epidemiology , Models, Statistical , Risk-Taking , Substance Abuse, Intravenous/epidemiology , Adolescent , Adult , Age Factors , Child , Cross-Sectional Studies , Female , Health Surveys , Humans , Incidence , Male , Middle Aged , Needle Sharing/statistics & numerical data , Prevalence , Prisoners/statistics & numerical data , Risk Assessment , Risk Factors , Scotland/epidemiology , Time Factors , Young Adult
14.
Parasitology ; 139(4): 441-53, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22309815

ABSTRACT

A mathematical model that describes the transmission dynamics of Theileria annulata is proposed that consists of 2 host components: the Hyalomma tick population and a compartmental model of T. annulata infection in the cattle population. The model was parameterized using data describing tick infestation and the infection status of cattle in Turkey from 2006 to 2008. The tick attachment rates are highly seasonal and because of the temporal separation of infectious and susceptible ticks virtually all ticks are infected by carrier cattle, so that annual peaks of disease in cattle do not impact on infection in the Hyalomma tick population. The impact of intervention measures that target the tick population both on the host and in the environment and their impact on the transmission of T. annulata were investigated. Interventions that have a limited 'one-off' impact and interventions that have a more permanent impact were both considered. The results from the model show the importance of targeting ticks during the period when they have left their first host as nymphs but have yet to feed on their second host.


Subject(s)
Arachnid Vectors/parasitology , Cattle Diseases/transmission , Ixodidae/parasitology , Models, Biological , Theileria annulata , Theileriasis/transmission , Tick Infestations/veterinary , Animals , Arachnid Vectors/growth & development , Carrier State/parasitology , Carrier State/transmission , Cattle , Cattle Diseases/parasitology , Ixodidae/growth & development , Nymph/growth & development , Seasons , Theileria annulata/isolation & purification , Theileria annulata/physiology , Theileriasis/parasitology , Tick Infestations/transmission , Turkey
16.
J Dent Res ; 101(3): 261-269, 2022 03.
Article in English | MEDLINE | ID: mdl-34636266

ABSTRACT

Detection and diagnosis of caries-typically undertaken through a visual-tactile examination, often with supporting radiographic investigations-is commonly regarded as being broadly effective at detecting caries that has progressed into dentine and reached a threshold where restoration is necessary. With earlier detection comes an opportunity to stabilize disease or even remineralize the tooth surface, maximizing retention of tooth tissue and preventing a lifelong cycle of restoration. We undertook a formal comparative analysis of the diagnostic accuracy of different technologies to detect and inform the diagnosis of early caries using published Cochrane systematic reviews. Forming the basis of our comparative analysis were 5 Cochrane diagnostic test accuracy systematic reviews evaluating fluorescence, visual or visual-tactile classification systems, imaging, transillumination and optical coherence tomography, and electrical conductance or impedance technologies. Acceptable reference standards included histology, operative exploration, or enhanced visual assessment (with or without tooth separation) as appropriate. We conducted 2 analyses based on study design: a fully within-study, within-person analysis and a network meta-analysis based on direct and indirect comparisons. Nineteen studies provided data for the fully within-person analysis and 64 studies for the network meta-analysis. Of the 5 technologies evaluated, the greatest pairwise differences were observed in summary sensitivity points for imaging and all other technologies, but summary specificity points were broadly similar. For both analyses, the wide 95% prediction intervals indicated the uncertainty of future diagnostic accuracy across all technologies. The certainty of evidence was low, downgraded for study limitations, inconsistency, and indirectness. Summary estimates of diagnostic accuracy for most technologies indicate that the degree of certitude with which a decision is made regarding the presence or absence of disease may be enhanced with the use of such devices. However, given the broad prediction intervals, it is challenging to predict their accuracy in any future "real world" context.


Subject(s)
Dental Caries Susceptibility , Dental Caries , Dental Caries/diagnostic imaging , Humans , Sensitivity and Specificity , Systematic Reviews as Topic , Transillumination
17.
Eur J Vasc Endovasc Surg ; 42(6): 775-86, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21908210

ABSTRACT

OBJECTIVE: To determine factors that may influence the perioperative mortality after endovascular repair of ruptured abdominal aortic aneurysms (RAAAs) using metaregression analysis. METHODS: A meta-analysis of all English-language literature with information on mortality rates after endovascular repair of RAAAs was conducted. A metaregression was subsequently performed to determine the impact on mortality of the following 8 factors: patient age; mid-time study point; anaesthesia; endograft configuration; haemodynamic instability; use of aortic balloon; conversion to open repair; and abdominal compartment syndrome. RESULTS: The pooled perioperative mortality across the 46 studies (1397 patients) was 24.3% (95% CI: 20.7-28.3%). Of the 8 variables, only bifurcated approach was significantly associated with reduced mortality (p = 0.005). A moderate negative correlation was observed between bifurcated approach and haemodynamic instability (-0.35). There was still a strong association between bifurcated approach and mortality after simultaneously adjusting for haemodynamic instability, indicating that the latter was not a major factor in explaining the observed association. CONCLUSIONS: Endovascular repair of RAAAs is associated with acceptable mortality rates. Patients having a bifurcated endograft were less likely to die. This may be due to some surgeons opting for a bifurcated approach in patients with better haemodynamic condition. Further studies will be needed to clarify this.


Subject(s)
Angioplasty/mortality , Aortic Aneurysm, Abdominal/mortality , Aortic Aneurysm, Abdominal/therapy , Aortic Rupture/mortality , Aortic Rupture/therapy , Aged , Aged, 80 and over , Blood Vessel Prosthesis Implantation , Cause of Death , Female , Hospital Mortality , Humans , Intra-Abdominal Hypertension/mortality , Male , Prognosis , Regression Analysis , Risk Factors
18.
J Colloid Interface Sci ; 590: 268-276, 2021 May 15.
Article in English | MEDLINE | ID: mdl-33548610

ABSTRACT

HYPOTHESIS: The formation of polyion complexes (PICs) comprising thermoresponsive polymers is intended to result in the formation of aggregates that undergo significant structural changes with temperature. Moreover the observed modifications might be critically affected by polymer structure and PICs composition. EXPERIMENTS: Different block copolymers based on cationic poly(3-acrylamidopropyltrimethylammonium chloride) and thermoresponsive poly(N-isopropylacrylamide) were synthesized by aqueous RAFT/MADIX polymerization at room temperature. Addition of poly(acrylic acid) in a controlled fashion led to the formation of PICs aggregates. The structural changes induced by temperature were characterized by differential scanning calorimetry, Nuclear Magnetic Resonance spectroscopy and scattering methods. FINDINGS: Thermoresponsive PICs undergo significant structural changes when increasing temperature above the cloud point of the thermoresponsive block. The reversibility of these phenomena depends strongly on the structural parameters of the block copolymers and on PICs composition.

19.
J Exp Med ; 152(2): 361-76, 1980 Aug 01.
Article in English | MEDLINE | ID: mdl-6967514

ABSTRACT

A method is presented for covalently bonding Haemophilus influenzae type b capsular polysaccharide (HIB Ps) to several proteins. The method is efficient and relies upon the use of adipic dihydrazide as a spacer between the capsular polysaccharide and the carrier protein. In contrast to the poor immunogenicity of the purified HIB Ps in mice and rabbits, the HIB Ps-protein conjugates induced serum anti-type b antibodies having bactericidal activity at levels shown to be protective in humans when low doses were injected subcutaneously in a saline solution. The antibody response in mice was related to the dose of the conjugates, increased with the number of injections, and could be primed by the previous injection of the carrier protein. The HIB Ps-protein conjugates were immunogenic in three different mouse strains. The importance of the carrier molecule for the enhanced immunogenicity of the HIB Ps-protein conjugates was shown by the failure of HIB Ps hybrids prepared with either the homologous polysaccharide or pneumococcus type 3 polysaccharide to induce antibodie in mice. Rabbits injected with the HIB Ps-protein conjugates emulsified in Freund's adjuvant produced high levels of serum anti-type b antibodies which induced a bactericidal effect upon H. influenzae type b organisms. It is proposed that the HIB Ps component of the polysaccharide protein conjugates has been converted to a thymic-dependent immunogen. This method may be used to prepare protein-polysaccharide conjugates with HIB Ps and other polysaccharides to be considered for human use.


Subject(s)
Bacterial Proteins/immunology , Haemophilus influenzae/immunology , Polysaccharides, Bacterial/immunology , Animals , Bacterial Proteins/isolation & purification , Carrier Proteins/pharmacology , Dose-Response Relationship, Immunologic , Haemophilus influenzae/analysis , Immunization , Mice , Molecular Weight , Polysaccharides, Bacterial/isolation & purification , Rabbits , Serum Albumin/immunology
20.
J Exp Med ; 149(3): 669-85, 1979 Mar 01.
Article in English | MEDLINE | ID: mdl-372481

ABSTRACT

The chemical basis for the alternating antigenic change called form variation noted for the Escherichia coli K1-capsular polysaccharide has been shown by 13C nuclear magnetic resonance to be a result of random O-acetylation of C7 and C9 carbons of the alpha-2-8-linked sialic acid homopolymer. A serologic method (antiserum agar) was developed to identify and isolate the form variants. The O-acetyl positive and O-acetyl negative K1 polysaccharides had unique biochemical and immunologic properties. The O-acetyl-positive variants resisted neuraminidase hydrolysis in contrast to the susceptibility of the O-acetyl negative variant to this enzyme. In addition, O-acetylation altered the antigenicity of the O-acetyl polysaccharides. When injected as whole organisms, O-acetyl positive organisms produced anti-K1 -antibodies in rabbits specific for this polysaccharide variant. O-acetyl negative organisms were comparatively less immunogenic; however, antibodies induced by these organisms reacted with both K1 polysaccharide variants. Burros, injected with either variant, produced antibodies reactive with both K1 polysaccharides.


Subject(s)
Antigens, Bacterial/analysis , Escherichia coli/immunology , Polysaccharides, Bacterial/immunology , Acetylation , Antibodies, Bacterial , Antibody Formation , Magnetic Resonance Spectroscopy , Neuraminidase/metabolism , Serotyping , Sialic Acids
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