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A 1.7 Å structure is presented for an active form of the virulence factor ScpB, the C5a peptidase from Streptococcus agalactiae. The previously reported structure of the ScpB active site mutant exhibited a large separation (~20 Å) between the catalytic His and Ser residues. Significant differences are observed in the catalytic domain between the current and mutant ScpB structures resulting with a high RMSDCα (4.6 Å). The fold of the active form of ScpB is nearly identical to ScpA (RMSDCα 0.2 Å), the C5a-peptidase from Streptococcus pyogenes. Both ScpA and ScpB have comparable activity against human C5a, indicating neither enzyme require host proteins for C5a-ase activity. These studies are a first step in resolving reported differences in the specificities of these enzymes.
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Endopeptidases , Streptococcus agalactiae , Humanos , Streptococcus agalactiae/metabolismo , Domínio Catalítico , Endopeptidases/química , Adesinas Bacterianas/química , Adesinas Bacterianas/metabolismo , Catálise , Streptococcus pyogenesRESUMO
BACKGROUND: Adrenocortical carcinoma (ACC) staging does not account for the number of positive nodes. The prognostic value of quantitative metastatic nodal burden is unknown. METHODS: The National Cancer Database was retrospectively queried from 2004-2016 to identify patients with Stage I-III ACC undergoing adrenalectomy. Patients who underwent lymphadenectomy (LAD) were further studied. Demographics, TNM staging, tumor characteristics, and surgical approach were analyzed. RESULTS: 386 LADs were identified. The median number of nodes examined was 2 (IQR 2-6), with no difference by surgical approach '[laparoscopic, 3 (1-3); robotic, 1.5 (1-4.5); open, 2 (1-7), p = 0.493]. In LADs with cN0 disease, positive nodes were seen in 17.5% of patients; an average of 6 (1-12) nodes were examined in patients who upstaged to pN1 disease compared with an average of 2 (1-6) nodes in those who remained pN0. Median survival was incrementally worse for patients with more positive nodes (62.8 vs. 21.9 vs. 13.7 vs. 11.3 vs. 10.7 months for 0, 1, 2, 3, and ≥ 4 positive nodes, respectively, p < 0.01). On multivariate analysis, significant prognostic factors for poor survival included older age, ≥ 2 comorbidities, pT3, and pT4. The strongest prognostic factor for poor survival was the number of positive nodes (1 node, hazards ratio [HR] 2.3, 95% confidence interval [CI] 1.5-3.6; 2 nodes, HR 1.3, 95% CI 0.6-3.0; 3 nodes, HR 3.0, 95% CI 1.1-8.0; ≥ 4 nodes, HR 4.0, 95% CI 2.5-6.2). Lymphadenectomy was associated with improved survival (HR 0.82, 95% CI 0.67-0.99). CONCLUSIONS: Higher quantitative metastatic nodal burden is a robust prognostic factor for worse survival in ACC.
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Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Carcinoma Adrenocortical/cirurgia , Idoso , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Metástase Linfática , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
BACKGROUND: Surgical resection with negative margins is the treatment of choice for adrenocortical carcinoma (ACC). This study was undertaken to determine factors associated with negative resection margins. METHODS: National Cancer Database was queried from 2010 to 2016 to identify patients with AJCC/ENSAT Stage I-III ACC who underwent adrenalectomy. Patient, tumor, facility, and operative characteristics were compared by margin status (positive-PM or negative-NM) and operative approach (open-OA, laparoscopic-LA, or robotic-RA). Multivariable logistic regression was used to identify factors associated with PM. RESULTS: Eight hundred and eighty-one patients were identified, of which 18.4% had PM and 81.6% had NM. Patients with advanced pathologic T stage and pathologic N1 stage were more likely to have PM (vs. NM) (T3, 49.7% vs. 24.8%, p < 0.01; T4, 26.2% vs. 10.0%, p < 0.01; N1, 6.7% vs. 3.5%, p < 0.01). Patients undergoing OA (vs. LA and RA) were more likely to have advanced clinical T stage (T4, 16.6% vs. 5.7% vs. 7.8%, p < 0.01) and larger tumors (> 6 cm, 84.6% vs. 64.1% vs. 62.3%, p < 0.01). High-volume centers (≥ 5 cases) were more likely to utilize OA. Patients undergoing LA (vs. RA) were more likely to require conversion to open (20.3% vs. 7.8%, p = 0.011). On multivariable analysis, factors associated with higher odds of PM included T3 disease (OR 7.02, 95% CI 2.66-18.55), T4 disease (OR 10.22, 95% CI 3.66-28.53), and LA (OR 1.99, 95% CI 1.28-3.09). High-volume centers were associated with lower odds of PM (OR 0.67, 95% CI 0.45-0.98). There was no significant difference in margin status between OA and RA (OR 1.44, 95% CI 0.71-2.90). CONCLUSION: Centers with higher ACC case volumes have lower odds of PM and utilize OA more often. LA is associated with higher odds of PM, whereas RA is not. These factors should be considered when planning the operative approach for ACC.
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Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Laparoscopia , Humanos , Carcinoma Adrenocortical/cirurgia , Carcinoma Adrenocortical/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Neoplasias do Córtex Suprarrenal/patologia , Margens de Excisão , Adrenalectomia , Estudos RetrospectivosRESUMO
INTRODUCTION: Surgery is the initial treatment of choice for patients with resectable adrenocortical carcinoma (ACC). We sought to determine factors associated with non-operative management of resectable ACC. METHODS: 2004-2016 National Cancer Database (NCDB) was queried to identify patients with AJCC/ENSAT Stage I-III ACC. Patients who underwent surgery (S) were compared to those who did not undergo surgery (NS). Multivariate logistic regression was used to identify factors associated with NS. Kaplan-Meier estimates used to assess survival. RESULTS: Two thousand-seventy patients with Stage I-III ACC were identified, of which 17.5% were NS. 85.9% of NS patients were not offered surgery; 69.9% of NS patients did not receive chemotherapy or radiation therapy. NS were older and less likely to receive care at an Academic center or high volume center (≥5 cases during the study period). NS patients were more likely to have advanced T stage and N1 disease. On multivariate regression, factors associated with lower odds of surgery include older age (OR 1.03, 95% CI 1.02-1.06), T4 disease (OR 3.34, 95% CI 1.05-10.68), and treatment at a community center (OR 2.92, 95% CI 1.58-5.40). Overall median survival was significantly poorer for NS patients (50.4 versus 78.4 months, P < 0.01). CONCLUSION: Patients with locally advanced ACC are less likely to undergo an operation, while those treated at centers with more operative experience or Academic facilities are more likely to undergo an operation. As the surgery-first approach is the current standard of care for resectable ACC, these patients may be best served at high volume Academic facilities.
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Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Neoplasias do Córtex Suprarrenal/cirurgia , Carcinoma Adrenocortical/cirurgia , Humanos , Estimativa de Kaplan-Meier , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Crowdfunding has become a unique response to the challenge of health care expenses, yet it has been rarely studied by the medical community. We looked to describe the scope of crowdfunding in thyroid surgery and analyze the factors that contribute toward a successful campaign. METHODS: In November 2018, active campaigns were retrieved from a popular crowdfunding Web site using search terms thyroidectomy and thyroid surgery and filtered to include only campaigns that originated in the United States. RESULTS: About 1052 thyroid surgery-related campaigns were analyzed. About 836 (79.5%) involved female patients and 43 (4.1%) pediatric patients. About 792 campaigns (75.3%) referred to thyroid cancer as a primary condition, 163 (15.5%) benign thyroid disease, and 97 (9.2%) other conditions. The average amount raised per campaign was $2514.54 (range, $0-$53,160). About 338 (32.1%) campaigns were self-posted, 317 (30.1%) posted by family, and 397 (37.7%) posted by friends. Median campaign duration was 20 mo, with a median number of 16 donors, 17 hearts, and 136 social media shares. Campaigns related to thyroid cancer raised more funds ($2729.97) than benign ($1669.84) or other ($2175.03) conditions (P < 0.001). Campaigns submitted by friends ($3524.78) received more funding than those by self ($1672.48) or family ($2147.19) (P < 0.001). Campaign duration, donor number, share number, and hearts were also significant predictors of amount raised. CONCLUSIONS: For thyroid surgery-related crowdfunding, campaigns referring to thyroid cancer had the highest amount of funds raised. Campaigns created by friends and other factors related to increased community engagement such as social media shares were also related to increased funds.
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Crowdsourcing/estatística & dados numéricos , Gastos em Saúde , Mídias Sociais/estatística & dados numéricos , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/economia , Adulto , Criança , Crowdsourcing/economia , Crowdsourcing/métodos , Feminino , Humanos , Masculino , Mídias Sociais/economia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/economia , Estados UnidosRESUMO
BACKGROUND: Robotic surgery offers advantages over conventional operative approaches but may also be associated with higher costs and additional risks. Analyzing surgical flow disruptions (FDs), defined as "deviations from the natural progression of an operation," can help target training techniques and identify opportunities for improvement. MATERIALS AND METHODS: Thirty-two robotic surgery operations were observed over a 6-wk period at one 900-bed surgical center. FDs were recorded in detail and classified into one of 11 different categories. Procedure type, robot model, and resident involvement were also recorded. Linear regression analyses were used to evaluate the effects of these parameters on FDs and operative duration. RESULTS: Twenty-one prostatectomies, eight sacrocolpopexies, and three nephrectomies were observed. The mean number of FDs was 48.2 (95% confidence interval [CI] 38.6-54.8 FDs), and mean operative duration was 163 min (95% CI 148-179 min). Each FD added 2.4 min (P = 0.025) to a case's total operative duration. The number and rate of FDs were significantly affected by resident involvement (P = 0.008 and P = 0.006, respectively). Resident cases demonstrated mostly training, equipment, and robot switch FDs, whereas nonresident cases demonstrated mostly equipment, instrument changes, and external factor FDs. CONCLUSIONS: Although the FDs encountered in resident training are more frequent, they may not significantly increase operative duration. Other FDs, such as equipment or external factors, may be more impactful. Limiting these specific FDs should be the focus of performance improvement efforts.
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Eficiência Organizacional , Nefrectomia/métodos , Duração da Cirurgia , Equipe de Assistência ao Paciente/organização & administração , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos , Humanos , Internato e Residência , Modelos Lineares , Nefrectomia/educação , Nefrectomia/estatística & dados numéricos , Estudos Prospectivos , Prostatectomia/educação , Prostatectomia/estatística & dados numéricos , Procedimentos Cirúrgicos Robóticos/educação , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Cirurgiões/educação , Cirurgiões/organização & administração , Estados UnidosRESUMO
Solitary bone plasmacytomas and plasma cell myeloma are clonal proliferations of plasma cells. Many patients with solitary bone plasmacytomas develop plasma cell myeloma on follow-up. We present a case of a 70-year-old man who presented with fracture and a lytic lesion in the subtrochanteric region of the left femur and was assigned a diagnosis of solitary bone plasmacytoma. He received local curative radiotherapy. However, 4 months later his serum M protein and ß2-microglobulin levels increased to 2.31 g/dL and 5.965 mg/L, respectively. He complained of abdominal fullness and constipation. Ultrasound and non-contrast CT imaging revealed multiple retroperitoneal masses. Colonoscopic examination was normal. Biopsy of the a retroperitoneal mass confirmed it to be a plasmacytoma. Repeat hemogram, blood urea, serum creatinine, skeletal survey, and bone marrow examination revealed no abnormalities. This is an unusual presentation of plasma cell myeloma, which manifested as multiple huge extramedullary retroperitoneal masses and arose from a solitary bone plasmacytoma, without related end organ or tissue impairment and bone marrow plasmacytosis. The patient succumbed to his disease 8 months after the appearance of the retroperitoneal masses. This case highlights the importance of close monitoring of patients diagnosed with solitary bone plasmacytoma with increased serum M protein and serum ß2-microglobulin levels, so that early therapy can be instituted to prevent conversion to plasma cell myeloma.
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Reconstruction of maxillary defects can be carried out using a variety of treatment modalities. The choice of modality depends on numerous factors, including the size and extent of the defect, patient characteristics, and existing comorbidities. One of the various options is reconstruction and rehabilitation using a fixed prosthesis supported over a zygomatic implant. In maxillectomy cases, a zygomatic implant can be used to improve the retention of the obturator prosthesis, as the loss of alveolar bone makes it impossible to use conventional endosseous implants. Although zygomatic implants are reported to have high success rates, they are not free of complication. We hereby present a rare complication associated with the placement of a zygomatic implant in a patient with COVID-19-associated mucormycosis who underwent operation. This rare complication has never been reported before. This case report also highlights on the management of complications involving displacement of a zygomatic implant in the infratemporal region.
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COVID-19 , Mucormicose , Zigoma , Humanos , COVID-19/complicações , Zigoma/cirurgia , Mucormicose/cirurgia , Masculino , Implantes Dentários , Pessoa de Meia-Idade , Maxila/cirurgia , Implantação Dentária EndósseaRESUMO
BACKGROUND: The utilization of robot-assisted approaches to surgery has increased significantly over the last two decades. This has introduced novel complexities into the operating room environment, requiring management of new challenges and workflow adaptation. This study aimed to analyze challenges in the surgical setup for complex upper gastrointestinal robot-assisted surgery (UGI-RAS) and identify opportunities for solutions. METHODS: Direct observations of surgical setup processes for UGI-RAS were performed by a trained Human Factors researcher at a non-profit academic medical center in Southern California. Setup tasks were subdivided into five phases: (1) before wheels-in; (2) patient transfer and anesthesia induction; (3) patient preparation; (4) surgery preparation; and (5) robot docking. Start/end times for each phase/task were documented along with workflow disruption (FD) narratives and timestamps. Setup tasks and FDs were analyzed using descriptive statistics. RESULTS: Twenty UGI-RAS setup procedures were observed between May-November 2023: sleeve gastrectomy +/- hiatal hernia repair (n = 9, 45.00%); para-esophageal hernia repair +/- fundoplication (n = 8, 40.00%); revision to Roux-en-Y gastric bypass (n = 2, 10.00%); and gastric band removal (n = 1, 5.00%). Frequent FDs included planning breakdowns (n = 20, 29.85%), equipment/supply management (n = 17, 25.37%), patient care coordination (n = 8, 11.94%), and equipment challenges (n = 8, 11.94%). Eleven of 20 observations were first-start cases, of which 10 experienced delayed starts. DISCUSSION: Interventions aimed at improving workflows during UGI-RAS setup include performing pre-operative team huddles and conducting trainings aimed at team coordination and equipment challenges. These solutions could result in improved teamwork, efficiency, and communication while reducing case start delays and turnover time.
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Introduction: Despite the advances in vaccination, there are still several challenges in reaching millions of children in low- and middle-income countries (LMICs). In this review, we present an extensive summary of the various strategies used for improving routine immunization in LMICs to aid program implementers in designing vaccination interventions. Methods: Experimental and quasi-experimental impact evaluations conducted in LMICs evaluating the effectiveness of interventions in improving routine immunization of children aged 0-5 years or the intermediate outcomes were included from 3ie's review of systematic reviews. Some additional impact evaluation studies published in recent years in select LMICs with large number of unvaccinated children were also included. Studies were coded to identify interventions and the barriers in the study context using the intervention framework developed in 3ie's Evidence Gap Map and the WHO's Behavioral and Social Drivers (BeSD) of vaccination framework, respectively. Qualitative analysis of the content was conducted to analyze the intervention strategies and the vaccination barriers that they addressed. Results and conclusion: One hundred and forty-two impact evaluations were included to summarize the interventions. To address attitudinal and knowledge related barriers to vaccination and to motivate caregivers, sensitization and educational programs, media campaigns, and monetary or non-monetary incentives to caregivers, that may or may not be conditional upon certain health behaviors, have been used across contexts. To improve knowledge of vaccination, its place, time, and schedule, automated voice messages and written or pictorial messages have been used as standalone or multicomponent strategies. Interventions used to improve service quality included training and education of health workers and providing monetary or non-monetary perks to them or sending reminders to them on different aspects of provision of vaccination services. Interventions like effective planning or outreach activities, follow-up of children, tracking of children that have missed vaccinations, pay-for-performance schemes and health system strengthening have also been used to improve service access and quality. Interventions aimed at mobilizing and collaborating with the community to impact social norms, attitudes, and empower communities to make health decisions have also been widely implemented.
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Programas de Imunização , Humanos , Pré-Escolar , Lactente , Países em Desenvolvimento , Vacinação/estatística & dados numéricos , Recém-Nascido , Conhecimentos, Atitudes e Prática em Saúde , Imunização/estatística & dados numéricosRESUMO
OBJECTIVE: An umbrella review providing a comprehensive synthesis of the interventions that are effective in providing routine immunisation outcomes for children in low and middle-income countries (L&MICs). DESIGN: A systematic review of systematic reviews, or an umbrella review. DATA SOURCES: We comprehensively searched 11 academic databases and 23 grey literature sources. The search was adopted from an evidence gap map on routine child immunisation sector in L&MICs, which was done on 5 May 2020. We updated the search in October 2021. ELIGIBILITY CRITERIA: We included systematic reviews assessing the effectiveness of any intervention on routine childhood immunisation outcomes in L&MICs. DATA EXTRACTION AND SYNTHESIS: Search results were screened by two reviewers independently applying predefined inclusion and exclusion criteria. Data were extracted by two researchers independently. The Specialist Unit for Review Evidence checklist was used to assess review quality. A mixed-methods synthesis was employed focusing on meta-analytical and narrative elements to accommodate both the quantitative and qualitative information available from the included reviews. RESULTS: 62 systematic reviews are included in this umbrella review. We find caregiver-oriented interventions have large positive and statistically significant effects, especially those focusing on short-term sensitisation and education campaigns as well as written messages to caregivers. For health system-oriented interventions the evidence base is thin and derived from narrative synthesis suggesting positive effects for home visits, mixed effects for pay-for-performance schemes and inconclusive effects for contracting out services to non-governmental providers. For all other interventions under this category, the evidence is either limited or not available. For community-oriented interventions, a recent high-quality mixed-methods review suggests positive but small effects. Overall, the evidence base is highly heterogenous in terms of scope, intervention types and outcomes. CONCLUSION: Interventions oriented towards caregivers and communities are effective in improving routine child immunisation outcomes. The evidence base on health system-oriented interventions is scant not allowing us to reach firm conclusions, except for home visits. Large evidence gaps exist and need to be addressed. For example, more high-quality evidence is needed for specific caregiver-oriented interventions (eg, monetary incentives) as well as health system-oriented (eg, health workers and data systems) and community-oriented interventions. We also need to better understand complementarity of different intervention types.
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Países em Desenvolvimento , Humanos , Criança , Programas de Imunização , Imunização , Revisões Sistemáticas como Assunto , CuidadoresRESUMO
The Streptococcal C5a peptidase (ScpA) specifically inactivates the human complement factor hC5a, a potent anaphylatoxin recently identified as a therapeutic target for treatment of COVID-19 infections. Engineering of ScpA to enhance its potential as a therapeutic will require detailed examination of the basis for its highly selective activity. The emerging view of ScpA and related subtilases is that selection of their substrates is a dynamic two-step process involving flexibility in the domains around the active site and in the C-ter of the substrate. Surface plasmon resonance (SPR) analyses of the ScpA-hC5a interaction have shown that high affinity binding of the substrate is driven by electrostatic interactions between an exosite on the Fn2 domain of the enzyme and the bulky N-ter cleavage product (PN, 'core' residues 1-67) of C5a [1]. Introduction of a D783A mutation in the Fn2 exosite, located approximately 50 Å from the catalytic serine, was shown to significantly reduce substrate binding affinity and k cat of the enzyme. X-ray crystallographic studies on the D783A mutant (ScpAD783A) were undertaken to better interpret the impact of this mutation on the specificity and activity of ScpA. Here we present the 1.9 Å X-ray diffraction data for ScpAD783A and the molecular replacement solution for the structure. Both raw diffraction images and coordinates have been made available on public databases. Additional details on the related SPR and enzyme kinetics analyses on ScpAD783A reported in Jain et al. [2].
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OBJECTIVE: To support evidence-informed decision-making, we created an evidence gap map to characterise the evidence base on the effectiveness of interventions in improving routine childhood immunisation outcomes in low-income and middle-income countries (LMICs). METHODS: We developed an intervention-outcome matrix with 38 interventions and 43 outcomes. We searched academic databases and grey literature sources for relevant impact evaluations (IEs) and systematic reviews (SRs). Search results were screened on title/abstract. Those included on title/abstract were retrieved for full review. Studies meeting the eligibility criteria were included and data were extracted for each included study. All screening and data extraction was done by two independent reviewers. We analysed these data to identify trends in the geographic distribution of evidence, the concentration of evidence across intervention and outcome categories, and attention to vulnerable populations in the literature. RESULTS: We identified 309 studies, comprising 226 completed IEs, 58 completed SRs, 24 ongoing IEs and 1 ongoing SR. Evidence from IEs is heavily concentrated in a handful of countries in sub-Saharan Africa and South Asia. Among interventions, the most frequently evaluated are those related to education and material incentives for caregivers or health workers. There are gaps in the study of non-material incentives and outreach to vulnerable populations. Among outcomes, those related to vaccine coverage and health are well covered. However, evidence on intermediate outcomes related to health system capacity or barriers faced by caregivers is much more limited. CONCLUSIONS: There is valuable evidence available to decision-makers for use in identifying and deploying effective strategies to increase routine immunisation in LMICs. However, additional research is needed to address gaps in the evidence base.
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Países em Desenvolvimento , Vacinação , Criança , Humanos , Pessoal de Saúde/educação , Pobreza , Populações VulneráveisRESUMO
INTRODUCTION: As global child vaccination coverage has plateaued, understanding how to increase routine child vaccination rates further is key to avoiding preventable disease and death. To analyse how community engagement strategies can increase child vaccination, we synthesise the results from formative evaluations of interventions that aimed to increase vaccination coverage in Ethiopia, Myanmar, Nigeria, and Pakistan. METHODS: This paper uses an inductive qualitative approach to synthesise the results from the six evaluations, gathering lessons for designing context appropriate interventions that are feasible to implement and acceptable to providers, communities, and caregivers. RESULTS: Assessing contextual, caregiver-level and provider-level barriers to vaccination is key to identifying appropriate engagement strategies. Across all contexts, low knowledge about the schedule of vaccines and the importance of timeliness represented a barrier to child immunisation. Despite the variability in how studies measured and reported caregiver attitudes, vaccine hesitancy was not found to represent an important barrier to immunisation. Frontline health workers played a critical role in community engagement approaches to increase vaccination. Interventions successfully obtained community buy-in by centre-staging community members, especially leaders, ensuring their participation in monitoring, and making immunisation an agenda item on community platforms. Interventions were implemented through existing health systems with substantial assistance from research teams. Limited data was available about intervention costs. CONCLUSIONS: Interventions designed around community engagement strategies can be appropriate, acceptable, and feasible approaches to overcome barriers to vaccination in a variety of low- and middle-income country contexts. However, questions remain about the ability of health systems to implement interventions at scale, both from a cost perspective and a capacity perspective.
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Países em Desenvolvimento , Vacinas , Criança , Humanos , Imunização , Vacinação , Cobertura VacinalRESUMO
The C5a peptidase from Streptococcus pyogenes (ScpA) is a highly specific enzyme with potential therapeutic value. ScpA is a good model for studying determinants of specificity in the multidomain immunomodulatory enzymes (IMEs), which comprise a large family of bacterial surface proteases. The surface exposed region of ScpA has 5 main domains which includes 3 C-terminal Fn3-like domains (Fn1, Fn2 and Fn3) (Kagawa et al. 2009). Progressive deletion of the Fn3-like domains from the C-ter resulted in loss of enzyme activity and showed an important role for the Fn2 domain in enzyme function. Functional investigation of specific acidic residues on the Fn2 domain identified 3 residues 30-50 Å from the catalytic site (D783, E864 and D889) which impacted to differing degrees on binding and on catalysis, supporting the presence of an exosite on the Fn2. In particular, residue D783 was observed to impact on both substrate binding affinity and the activity of ScpA. A double mutant cycle analysis showed energetic coupling between the targeted ScpA residues and residues in the core portion (residues 1-67) of the C5a substrate. The data supports the presence of a communication network between the active site and the exosite on Fn2. These findings provide a basis for rational engineering of this important enzyme family to enhance stability, activity and/or specificity.
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OBJECTIVE: To support evidence informed decision-making, we systematically examine the effectiveness and cost-effectiveness of community engagement interventions on routine childhood immunisation outcomes in low-income and middle-income countries (LMICs) and identify contextual, design and implementation features associated with effectiveness. DESIGN: Mixed-methods systematic review and meta-analysis. DATA SOURCES: 21 databases of academic and grey literature and 12 additional websites were searched in May 2019 and May 2020. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We included experimental and quasi-experimental impact evaluations of community engagement interventions considering outcomes related to routine child immunisation in LMICs. No language, publication type, or date restrictions were imposed. DATA EXTRACTION AND SYNTHESIS: Two independent researchers extracted summary data from published reports and appraised quantitative risk of bias using adapted Cochrane tools. Random effects meta-analysis was used to examine effects on the primary outcome, full immunisation coverage. RESULTS: Our search identified over 43 000 studies and 61 were eligible for analysis. The average pooled effect of community engagement interventions on full immunisation coverage was standardised mean difference 0.14 (95% CI 0.06 to 0.23, I2=94.46). The most common source of risk to the quality of evidence (risk of bias) was outcome reporting bias: most studies used caregiver-reported measures of vaccinations received by a child in the absence or incompleteness of immunisation cards. Reasons consistently cited for intervention success include appropriate intervention design, including building in community engagement features; addressing common contextual barriers of immunisation and leveraging facilitators; and accounting for existing implementation constraints. The median intervention cost per treated child per vaccine dose (excluding the cost of vaccines) to increase absolute immunisation coverage by one percent was US$3.68. CONCLUSION: Community engagement interventions are successful in improving outcomes related to routine child immunisation. The findings are robust to exclusion of studies assessed as high risk of bias.
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Países em Desenvolvimento , Vacinação , Criança , Humanos , Imunização , Pobreza , PaisRESUMO
Immunisation is one of the most cost-effective interventions to prevent and control life-threatening infectious diseases. Nonetheless, rates of routine vaccination of children in low- and middle-income countries (LMICs) are strikingly low or stagnant. In 2019, an estimated 19.7 million infants did not receive routine immunisations. Community engagement interventions are increasingly being emphasised in international and national policy frameworks as a means to improve immunisation coverage and reach marginalised communities. This systematic review examines the effectiveness and cost-effectiveness of community engagement interventions on outcomes related to childhood immunisation in LMICs and identifies contextual, design and implementation features that may be associated with effectiveness. We identified 61 quantitative and mixed methods impact evaluations and 47 associated qualitative studies related to community engagement interventions for inclusion in the reteview. For cost-effectiveness analysis 14 of the 61 studies had the needed combination of cost and effectiveness data. The 61 included impact evaluations were concentrated in South Asia and Sub-Saharan Africa and spread across 19 LMICs. The review found that community engagement interventions had a small but significant, positive effect on all primary immunisation outcomes related to coverage and their timeliness. The findings are robust to exclusion of studies assessed as high risk of bias. Qualitative evidence indicates appropriate intervention design, including building in community engagement features; addressing common contextual barriers of immunisation and leveraging facilitators; and accounting for existing implementation constraints and practicalities on the ground are consistently cited as reasons for intervention success. Among the studies for which we were able to calculate cost-effectiveness, we find that the median non-vaccine cost per dose of intervention to increase immunisation coverage by 1% was US $3.68. Given the broad scope of the review in terms of interventions and outcomes, there is significant variation in findings. Among the various types of community engagement interventions, those that involve creation of community buy-in or development of new cadres of community-based structures were found to have consistent positive effect on more primary vaccination coverage outcomes than if the engagement is limited to the design or delivery of an intervention or is a combination of the various types. The evidence base for sub-group analysis for female children was sparse (only two studies) and the effect on coverage of both full immunisation and third dose of diphtheria pertussis tetanus for this group was insignificant.
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BACKGROUND: Impaired wound healing is a major complication associated with diabetes, involving a dysregulation and impairments in the inflammatory and angiogenic phases of wound healing. Here, we examine the effects of the neuropeptides substance P (SP) and neuropeptide Y (NPY) on dermal microvascular endothelial cell (DMVEC) angiogenesis and interleukin-8 (IL-8) expression, a known effector of the neuropeptide pathways in normal and hyperglycemic conditions in vitro. METHODS: DMVECs are treated with one of four glucose concentrations: 1) 5 mM glucose; 2) 10 mM glucose; 3) 30 mM glucose; or 4) 30 mM mannitol and cotreated with 100 nM NPY, 100 nM SP, or 10 ng/mL IL-8. Angiogenesis is assessed with proliferation and tube formation assays. IL-8 mRNA and protein expression are evaluated at days 1 and 7. RESULTS: As compared with noromoglycemia (5 mM glucose), hyperglycemia (30 mM glucose) decreases DMVEC proliferation and tube formation by 39% and 42%, respectively. SP cotreatment restores DMVEC proliferation (211%) and tube formation (152%), and decreases IL-8 expression (34%) in DMVECs exposed to hyperglycemic conditions. These effects are not observed with NPY. However, IL-8 treatment by itself does not affect proliferation or tube formation, suggesting that the effect of SP on DMVEC angiogenesis is unlikely through changes in IL-8 expression. CONCLUSION: Hyperglycemic conditions impair DMVEC proliferation and tube formation. SP mitigates the effect of hyperglycemia on DMVECs by increasing DMVEC proliferation and tube formation. These findings are not likely to be related to a dysregulation of IL-8 due to the lack of effects of hyperglycemia on IL-8 expression and the lack of effect of IL-8 on DMVEC proliferation and tube formation. The effect of SP on DMVECs makes SP a promising potential target for therapy in impaired wound healing in diabetes, but the exact mechanism remains unknown.
Assuntos
Endotélio Vascular/metabolismo , Hiperglicemia/metabolismo , Interleucina-8/biossíntese , Neovascularização Fisiológica/fisiologia , Neuropeptídeos/metabolismo , Cicatrização/fisiologia , Proliferação de Células , Células Cultivadas , Derme/irrigação sanguínea , Derme/metabolismo , Células Endoteliais/fisiologia , Endotélio Vascular/fisiologia , Endotélio Vascular/fisiopatologia , Humanos , Hiperglicemia/fisiopatologia , Microvasos/metabolismo , Neuropeptídeo Y/metabolismo , Substância P/metabolismoRESUMO
The Streptococcal C5a peptidase (ScpA) specifically inactivates the human complement factor hC5a, a potent anaphylatoxin recently identified as a therapeutic target for treatment of COVID-19 infections. Biologics used to modulate hC5a are predominantly monoclonal antibodies. Here we present data to support an alternative therapeutic approach based on the specific inactivation of hC5a by ScpA in studies using recombinant hC5a (rhC5a). Initial characterization of ScpA confirmed activity in human serum and against rhC5a desArg (rhC5adR), the predominant hC5a form in blood. A new FRET based enzyme assay showed that ScpA cleaved rhC5a at near physiological concentrations (K m 185 nM). Surface Plasmon Resonance (SPR) and Isothermal Titration Calorimetry (ITC) studies established a high affinity ScpA-rhC5a interaction (K D 34 nM, K D ITC 30.8 nM). SPR analyses also showed that substrate binding is dominated (88% of ΔG°bind) by interactions with the bulky N-ter cleavage product (PN, 'core' residues 1-67) with interactions involving the C-ter R74 contributing most of the remaining ΔG°bind. Furthermore, reduced binding affinity following mutation of a subset of positively charged Arginine residues of PN and in the presence of higher salt concentrations, highlighted the importance of electrostatic interactions. These data provide the first in-depth study of the ScpA-C5a interaction and indicate that ScpA's ability to efficiently cleave physiological concentrations of C5a is driven by electrostatic interactions between an exosite on the enzyme and the 'core' of C5a. The results and methods described herein will facilitate engineering of ScpA to enhance its potential as a therapeutic for excessive immune response to infectious disease.
RESUMO
Background: While numerous factors determine prognosis in papillary thyroid carcinoma (PTC), distant metastasis (M1) represents one of the most dire. Escalating nodal burden and aggressive histology may contribute to higher metastatic risk, but this relationship is poorly defined and challenging to anticipate. We evaluate the predictive impact of these histological features on predicting distant metastases at initial presentation. Methods: Univariate and multivariable logistic regression models of conventional and aggressive thyroid cancer variants (well-differentiated papillary thyroid carcinoma [WDPTC], diffuse sclerosing variant [DSV], tall cell variant [TCV], poorly differentiated thyroid cancer [PDTC], and anaplastic thyroid carcinoma [ATC]) identified via U.S. cancer registry data were constructed to determine associations between M1 status and quantitative nodal burden. Associations between metastatic lymph node (LN) number and M1 disease were modeled using univariate and multivariable logistic regression with interaction terms, as well as a linear continuous probability model. Results: Overall, M1 prevalence at disease presentation was 3.6% (n = 1717). When stratified by subtype, M1 prevalence varied significantly by histology (WDPTC [1.0%], DSV [2.3%], TCV [4.1%], PDTC [17.4%], ATC [38.4%] [p < 0.001]). For WDPTC, M1 prevalence escalated with metastatic LN number (0 LN+ [0.5%], 1-5 LN+ [2.0%], 6-10 LN+ [3.4%], >10 LN+ [5.5%] [p < 0.001]) and LN ratio (p < 0.001). A statistically significant interaction was observed between histology and increasing nodal burden for M1 risk. On multivariable analysis, each successive metastatic LN conferred increased M1 risk for WDPTC (odds ratio [OR] 1.06 [1.05-1.08], p < 0.001) and TCVs (OR 1.04 [1.02-1.07], p < 0.001). In contrast, other aggressive variants had a higher baseline M1 risk, but this did not vary based on the number of positive LN (DSV, OR 1.02 [0.95-1.10], p = 0.52; PDTC, OR 1.00 [0.98-1.02], p = 0.66; ATC, 1.00 [0.98-1.02], p = 0.97). Conclusions: Progressive nodal burden independently escalates the risk of distant metastasis in WDPTC and TCVs of PTC. Conversely, aggressive variants such as PDTC and ATC have substantial M1 risk at baseline and appear to be minimally affected by metastatic nodal burden. Consideration of these factors after surgery may help tailor clinical decision-making for treatment and surveillance. Further studies are warranted to calibrate the ideal management approach for these higher risk patient groups.