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2.
Ann Surg Oncol ; 27(2): 430-438, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31549320

RESUMO

BACKGROUND: Multidisciplinary treatment of rectal cancer, including neoadjuvant treatment, total mesorectal excision, and adjuvant chemotherapy, have improved oncological outcome. Preoperative radiation therapy is advocated by national and international guidelines in all patients with AJCC stage II and III rectal cancer. Although this treatment reduces local recurrence rates with no effect on overall survival, there are possible short- and long-term side effects of radiation exposure, so patients should be carefully selected for neoadjuvant radiation therapy. METHODS: We analyzed whether ventral or dorsal tumor location affects local recurrence rates following radical rectal resection. Patients who underwent radical rectal resection for mid or low rectal cancer in our department between October 2001 and December 2013 were included. Prognostic indicators for local recurrence were analyzed using univariate and multivariate analyses. RESULTS: Overall, 480 patients met the inclusion criteria. Univariate analysis identified surgical procedure (hazard ratio [HR] 1.9, p = 0.006), ventral tumor location (HR 3.8, p < 0.001), and a pathologic circumferential resection margin (pCRM) (HR 9.3, p < 0.001) as prognostic factors of local recurrence. Multivariate analysis revealed tumor location (HR 3.5, p < 0.001) and pCRM (HR 6.0, p = 0.002) as independent factors for local recurrence. Neoadjuvant treatment of AJCC stage II and III tumors reduced the local recurrence rate at ventral but not at dorsal tumor locations (p < 0.001). CONCLUSIONS: Ventral versus dorsal tumor location is an independent prognostic factor for local recurrence. Tumor location may aid in patient selection for neoadjuvant treatment.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Fatores de Risco , Resultado do Tratamento
3.
Crit Care ; 24(1): 65, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093763

RESUMO

BACKGROUND: Point-of-care ultrasound (POCUS) is nowadays an essential tool in critical care. Its role seems more important in neonates and children where other monitoring techniques may be unavailable. POCUS Working Group of the European Society of Paediatric and Neonatal Intensive Care (ESPNIC) aimed to provide evidence-based clinical guidelines for the use of POCUS in critically ill neonates and children. METHODS: Creation of an international Euro-American panel of paediatric and neonatal intensivists expert in POCUS and systematic review of relevant literature. A literature search was performed, and the level of evidence was assessed according to a GRADE method. Recommendations were developed through discussions managed following a Quaker-based consensus technique and evaluating appropriateness using a modified blind RAND/UCLA voting method. AGREE statement was followed to prepare this document. RESULTS: Panellists agreed on 39 out of 41 recommendations for the use of cardiac, lung, vascular, cerebral and abdominal POCUS in critically ill neonates and children. Recommendations were mostly (28 out of 39) based on moderate quality of evidence (B and C). CONCLUSIONS: Evidence-based guidelines for the use of POCUS in critically ill neonates and children are now available. They will be useful to optimise the use of POCUS, training programs and further research, which are urgently needed given the weak quality of evidence available.


Assuntos
Terapia Intensiva Neonatal , Sistemas Automatizados de Assistência Junto ao Leito , Ultrassonografia , Cuidados Críticos/métodos , Estado Terminal , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Terapia Intensiva Neonatal/métodos , Terapia Intensiva Neonatal/normas , Sistemas Automatizados de Assistência Junto ao Leito/normas , Revisões Sistemáticas como Assunto , Ultrassonografia/métodos , Ultrassonografia/normas
4.
BMC Pediatr ; 18(1): 75, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466967

RESUMO

BACKGROUND: Death audits have been used to describe pediatric mortality in under-resourced settings, where record keeping is often a challenge. This information provides the cornerstone for the foundation of quality improvement initiatives. Malawi, located in sub-Saharan Africa, currently has an Under-5 mortality rate of 64/1000. Kamuzu Central Hospital, in the capital city Lilongwe, is a busy government referral hospital, which admits up to 3000 children per month. A study published in 2013 reported mortality rates as high as 9%. This is the first known audit of pediatric death files conducted at this hospital. METHODS: A retrospective chart review on all pediatric deaths that occurred at Kamuzu Central Hospital (excluding deaths in the neonatal nursery) during a 13-month period was done using a standardized death audit form. A descriptive analysis was completed, including patient demographics, HIV and nutritional status, and cause of death. Modifiable factors were identified that may have contributed to mortality, including a lack of vital sign collection, poor documentation, and delays in the procurement or results of tests, studies, and specialist review. RESULTS: Seven hundred forty three total pediatric deaths were recorded and 700 deceased patient files were reviewed. The mortality rate by month ranged from a low of 2.2% to a high of 4.4%. Forty-four percent of deaths occurred within the first 24 h of admission, and 59% occurred within the first 48 h. The most common causes of death were malaria, malnutrition, HIV-related illnesses, and sepsis. CONCLUSIONS: The mortality rate for this pediatric referral center has dramatically decreased in the 6 years since the last published mortality data, but remains high. Areas identified for continued development include improved record keeping, improved patient assessment and monitoring, and more timely and reliable provision of testing and treatment. This study demonstrates that in low-resource settings, where reliable record keeping is often difficult, death audits are useful tools to describe the sickest patient population and determine factors possibly contributing to mortality that may be amenable to quality improvement interventions.


Assuntos
Mortalidade da Criança/tendências , Mortalidade Hospitalar/tendências , Mortalidade Infantil/tendências , Adolescente , Causas de Morte , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Malaui/epidemiologia , Masculino , Auditoria Médica , Estudos Retrospectivos , Centros de Atenção Terciária
5.
PLoS Genet ; 11(7): e1005373, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26197346

RESUMO

Cysteine-rich receptor-like kinases (CRKs) are transmembrane proteins characterized by the presence of two domains of unknown function 26 (DUF26) in their ectodomain. The CRKs form one of the largest groups of receptor-like protein kinases in plants, but their biological functions have so far remained largely uncharacterized. We conducted a large-scale phenotyping approach of a nearly complete crk T-DNA insertion line collection showing that CRKs control important aspects of plant development and stress adaptation in response to biotic and abiotic stimuli in a non-redundant fashion. In particular, the analysis of reactive oxygen species (ROS)-related stress responses, such as regulation of the stomatal aperture, suggests that CRKs participate in ROS/redox signalling and sensing. CRKs play general and fine-tuning roles in the regulation of stomatal closure induced by microbial and abiotic cues. Despite their great number and high similarity, large-scale phenotyping identified specific functions in diverse processes for many CRKs and indicated that CRK2 and CRK5 play predominant roles in growth regulation and stress adaptation, respectively. As a whole, the CRKs contribute to specificity in ROS signalling. Individual CRKs control distinct responses in an antagonistic fashion suggesting future potential for using CRKs in genetic approaches to improve plant performance and stress tolerance.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Estresse Oxidativo/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/enzimologia , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Ascomicetos/imunologia , DNA Bacteriano/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Proteínas Serina-Treonina Quinases/genética , Pseudomonas syringae/imunologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Xantina Oxidase/metabolismo
6.
Implant Dent ; 27(3): 332-341, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29652755

RESUMO

OBJECTIVE: The article studies state-of-the art physical therapeutic techniques as a high degree of relevance to minimize invalidation and improve quality of life for patients with dental osteosarcoma. MATERIALS AND METHODS: A randomized controlled clinical trial was conducted in 21 patients with osteogenic sarcoma of mandible (C41.1). There were 10 patients in the experimental group and 11 patients in the control group. RESULTS: A comprehensive treatment and rehabilitation program for patients with osteosarcoma of mandible was developed. The first part of the program comprised 3 basic phases: preop chemotherapy, surgery, and postop rehabilitation. The surgical treatment further included resection of an affected part of the mandible and primary repair of the defect with jaw fragments and an autoimplant joined together with the help of positioning devices. The postop rehabilitation included postop chemotherapy and mesodiencephalic modulation (MDM). The second part of the program comprised preop examination, modeling, using stereolytic 3-dimensional models of the mandible, corrective surgeries, including implantation into the autoimplant-a fragment of patient's fibula, and building of a removable titanium alloy-based denture. MDM sessions were administered after each invasive intervention. CONCLUSIONS: Higher psychological and physical well-being was observed in the experimental group as compared with the control group (P < 0.01) in 2 weeks after the first surgery and 2 months after scheduled corrective surgeries, which finished in denture installation.


Assuntos
Neoplasias Mandibulares/terapia , Osteossarcoma/terapia , Adulto , Estudos de Casos e Controles , Terapia Combinada , Dentaduras , Feminino , Humanos , Masculino , Neoplasias Mandibulares/reabilitação , Osteossarcoma/reabilitação , Qualidade de Vida , Resultado do Tratamento
7.
Plant Cell Environ ; 40(1): 36-50, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27245884

RESUMO

Nitric oxide (NO) is an important signalling molecule that is involved in many different physiological processes in plants. Here, we report about a NO-fixing mechanism in Arabidopsis, which allows the fixation of atmospheric NO into nitrogen metabolism. We fumigated Arabidopsis plants cultivated in soil or as hydroponic cultures during the whole growing period with up to 3 ppmv of NO gas. Transcriptomic, proteomic and metabolomic analyses were used to identify non-symbiotic haemoglobin proteins as key components of the NO-fixing process. Overexpressing non-symbiotic haemoglobin 1 or 2 genes resulted in fourfold higher nitrate levels in these plants compared with NO-treated wild-type. Correspondingly, rosettes size and weight, vegetative shoot thickness and seed yield were 25, 40, 30, and 50% higher, respectively, than in wild-type plants. Fumigation with 250 ppbv 15 NO confirmed the importance of non-symbiotic haemoglobin 1 and 2 for the NO-fixation pathway, and we calculated a daily uptake for non-symbiotic haemoglobin 2 overexpressing plants of 250 mg N/kg dry weight. This mechanism is probably important under conditions with limited N supply via the soil. Moreover, the plant-based NO uptake lowers the concentration of insanitary atmospheric NOx, and in this context, NO-fixation can be beneficial to air quality.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Hemoglobinas/metabolismo , Óxido Nítrico/metabolismo , Nitrogênio/farmacologia , Simbiose , Amônia/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Fumigação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nitratos/metabolismo , Óxido Nítrico/farmacologia , Nitritos/metabolismo , Fenótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Propanóis/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , S-Nitrosotióis/metabolismo
8.
Nano Lett ; 16(9): 5373-7, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27490749

RESUMO

According to the American skin cancer foundation, there are more new cases of skin cancer than the combined incidence of cancers of the breast, prostate, lung, and colon each year, and malignant melanoma represents its deadliest form. About 50% of all cases are characterized by a particular mutation BRAF(V600E) in the BRAF (Rapid Acceleration of Fibrosarcoma gene B) gene. Recently developed highly specific drugs are able to fight BRAF(V600E) mutated tumors but require diagnostic tools for fast and reliable mutation detection to warrant treatment efficiency. We completed a preliminary clinical trial applying cantilever array sensors to demonstrate identification of a BRAF(V600E) single-point mutation using total RNA obtained from biopsies of metastatic melanoma of diverse sources (surgical material either frozen or fixated with formalin and embedded in paraffin). The method is faster than the standard Sanger or pyrosequencing methods and comparably sensitive as next-generation sequencing. Processing time from biopsy to diagnosis is below 1 day and does not require PCR amplification, sequencing, and labels.


Assuntos
Análise Mutacional de DNA , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Biópsia , Humanos , Mutação
9.
J Exp Bot ; 67(22): 6337-6349, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27811003

RESUMO

This study aimed to understand the molecular mechanisms of nitrogen dioxide (NO2)-induced toxicity and cell death in plants. Exposure of Arabidopsis to high concentrations of NO2 induced cell death in a dose-dependent manner. No leaf symptoms were visible after fumigation for 1 h with 10 parts per million (ppm) NO2 However, 20 ppm NO2 caused necrotic lesion formation and 30 ppm NO2 complete leaf collapse, which had already started during the 1 h fumigation period. NO2 fumigation resulted in a massive accumulation of nitrite and in protein modifications by S-nitrosylation and tyrosine nitration. Nitric oxide (NO) at 30 ppm did not trigger leaf damage or any of the effects observed after NO2 fumigation. The onset of NO2-induced cell death correlated with NO and hydrogen peroxide (H2O2) signaling and a decrease in antioxidants. NO- and H2O2-accumulating mutants were more sensitive to NO2 than wild-type plants. Accordingly, experiments with specific scavengers confirmed that NO and H2O2 are essential promoters of NO2-induced cell death. Leaf injection of 100 mM nitrite caused an increase in S-nitrosylation, NO, H2O2, and cell death suggesting that nitrite functioned as a mediator of NO2-induced effects. A targeted screening of phytohormone mutants revealed a protective role of salicylic acid (SA) signaling in response to NO2 It was also shown that phytohormones were modulators rather than inducers of NO2-induced cell death. The established experimental set-up is a suitable system to investigate NO2 and cell death signaling in large-scale mutant screens.


Assuntos
Morte Celular/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Nitritos/metabolismo , Dióxido de Nitrogênio/farmacologia , Reguladores de Crescimento de Plantas/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Morte Celular/fisiologia , Relação Dose-Resposta a Droga , Óxido Nítrico/fisiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Ácido Salicílico/metabolismo
10.
Sensors (Basel) ; 16(7)2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27455276

RESUMO

For many diseases, where a particular organ is affected, chemical by-products can be found in the patient's exhaled breath. Breath analysis is often done using gas chromatography and mass spectrometry, but interpretation of results is difficult and time-consuming. We performed characterization of patients' exhaled breath samples by an electronic nose technique based on an array of nanomechanical membrane sensors. Each membrane is coated with a different thin polymer layer. By pumping the exhaled breath into a measurement chamber, volatile organic compounds present in patients' breath diffuse into the polymer layers and deform the membranes by changes in surface stress. The bending of the membranes is measured piezoresistively and the signals are converted into voltages. The sensor deflection pattern allows one to characterize the condition of the patient. In a clinical pilot study, we investigated breath samples from head and neck cancer patients and healthy control persons. Evaluation using principal component analysis (PCA) allowed a clear distinction between the two groups. As head and neck cancer can be completely removed by surgery, the breath of cured patients was investigated after surgery again and the results were similar to those of the healthy control group, indicating that surgery was successful.


Assuntos
Técnicas Biossensoriais/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Testes Respiratórios , Feminino , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Análise de Componente Principal
11.
Hum Resour Health ; 13: 60, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26193932

RESUMO

BACKGROUND: Eighty per cent of Malawi's 8 million children live in rural areas, and there is an extensive tiered health system infrastructure from village health clinics to district hospitals which refers patients to one of the four central hospitals. The clinics and district hospitals are staffed by nurses, non-physician clinicians and recently qualified doctors. There are 16 paediatric specialists working in two of the four central hospitals which serve the urban population as well as accepting referrals from district hospitals. In order to provide expert paediatric care as close to home as possible, we describe our plan to task share within a managed clinical network and our hypothesis that this will improve paediatric care and child health. PRESENTATION OF THE HYPOTHESIS: Managed clinical networks have been found to improve equity of care in rural districts and to ensure that the correct care is provided as close to home as possible. A network for paediatric care in Malawi with mentoring of non-physician clinicians based in a district hospital by paediatricians based at the central hospitals will establish and sustain clinical referral pathways in both directions. Ultimately, the plan envisages four managed paediatric clinical networks, each radiating from one of Malawi's four central hospitals and covering the entire country. This model of task sharing within four hub-and-spoke networks may facilitate wider dissemination of scarce expertise and improve child healthcare in Malawi close to the child's home. TESTING THE HYPOTHESIS: Funding has been secured to train sufficient personnel to staff all central and district hospitals in Malawi with teams of paediatric specialists in the central hospitals and specialist non-physician clinicians in each government district hospital. The hypothesis will be tested using a natural experiment model. Data routinely collected by the Ministry of Health will be corroborated at the district. This will include case fatality rates for common childhood illness, perinatal mortality and process indicators. Data from different districts will be compared at baseline and annually until 2020 as the specialists of both cadres take up posts. IMPLICATIONS OF THE HYPOTHESIS: If a managed clinical network improves child healthcare in Malawi, it may be a potential model for the other countries in sub-Saharan Africa with similar cadres in their healthcare system and face similar challenges in terms of scarcity of specialists.


Assuntos
Saúde da Criança , Atenção à Saúde , Pediatria , Assistentes Médicos , Médicos , População Rural , Trabalho , Criança , Acessibilidade aos Serviços de Saúde/normas , Hospitais , Humanos , Malaui , Melhoria de Qualidade , Encaminhamento e Consulta , Especialização
12.
Artigo em Inglês | MEDLINE | ID: mdl-39167706

RESUMO

BACKGROUND: Data on the presentation, management and outcomes of Lassa fever (LF) in children are limited. METHODS: Description of the clinical and biological features, treatment and outcomes of RT-PCR-confirmed LF in children aged under 15, enrolled in the LASCOPE prospective cohort study in Nigeria between April 2018 and February 2023. RESULTS: 124 children (aged under 12 months: 19; over 12 months: 105) were hospitalized with RT-PCR-confirmed LF. All received intravenous ribavirin. During follow-up, 99/124 (80%) had fever; 71/124 (57%) had digestive symptoms, vomiting (n = 56/122, 46%) and abdominal pain (n = 34/78 aged ≥ 5 years, 44%) more often than diarrhea (n = 19/124, 15%); 17/124 (14%) had hemorrhagic signs; 44/112 (39%) had a hematocrit lower than 25%, of whom 32/44 (73%) received transfusions; 44/88 (50%) developed hypotension; 18/112 (16.1%) developed KDIGO ≥ 2 acute kidney injury; 10/112 (8.9%) had KDIGO 3 acute kidney failure; 4/124 (3.2%) underwent renal replacement therapy. 7 children died, including 4 aged under 12 months (case fatality rate: under 12 months - 22%, 95% CI 7 - 48%; over 12 months - 2.9%, 95% CI 0.7 - 8.7%). In univariable analysis, age (p=0.003), impaired consciousness (p=0.026), and Lassa RT-PCR Ct value (p=0.006) were associated to Day 30 mortality. CONCLUSIONS: The fatality rate for children over 12 months hospitalized with LF was lower than that previously reported for adults. Hypotension and acute kidney injury were the most frequent organ dysfunctions. Bleeding was relatively infrequent. Anemia and the need for transfusion were common, the relative contribution of ribavirin-induced hemolysis being unknown.

13.
Anal Chem ; 85(18): 8676-83, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-23905589

RESUMO

A microcantilever based method for fluid viscosity and mass density measurements with high temporal resolution and microliter sample consumption is presented. Nanomechanical cantilever vibration is driven by photothermal excitation and detected by an optical beam deflection system using two laser beams of different wavelengths. The theoretical framework relating cantilever response to the viscosity and mass density of the surrounding fluid was extended to consider higher flexural modes vibrating at high Reynolds numbers. The performance of the developed sensor and extended theory was validated over a viscosity range of 1-20 mPa·s and a corresponding mass density range of 998-1176 kg/m(3) using reference fluids. Separating sample plugs from the carrier fluid by a two-phase configuration in combination with a microfluidic flow cell, allowed samples of 5 µL to be sequentially measured under continuous flow, opening the method to fast and reliable screening applications. To demonstrate the study of dynamic processes, the viscosity and mass density changes occurring during the free radical polymerization of acrylamide were monitored and compared to published data. Shear-thinning was observed in the viscosity data at higher flexural modes, which vibrate at elevated frequencies. Rheokinetic models allowed the monomer-to-polymer conversion to be tracked in spite of the shear-thinning behavior, and could be applied to study the kinetics of unknown processes.


Assuntos
Sistemas Computacionais , Glicerol/análise , Técnicas Analíticas Microfluídicas/métodos , Nanopartículas/química , Vibração , Glicerol/química , Viscosidade
14.
Sensors (Basel) ; 13(4): 5273-85, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23604028

RESUMO

A cantilever-based protein biosensor has been developed providing a customizable multilayer platform for the detection of antibodies. It consists of a biotin-terminated PEG layer pre-functionalized on the gold-coated cantilever surface, onto which NeutrAvidin is adsorbed through biotin/NeutrAvidin specific binding. NeutrAvidin is used as a bridge layer between the biotin-coated surface and the biotinylated biomolecules, such as biotinylated bovine serum albumin (biotinylated BSA), forming a multilayer sensor for direct antibody capture. The cantilever biosensor has been successfully applied to the detection of mouse anti-BSA (m-IgG) and sheep anti-BSA(s-IgG) antibodies. As expected, the average differential surface stress signals of about 5.7 ± 0.8 × 10(-3) N/m are very similar for BSA/m-IgG and BSA/s-IgG binding, i.e., they are independent of the origin of the antibody. A statistic evaluation of 112 response curves confirms that the multilayer protein cantilever biosensor shows high reproducibility. As a control test, a biotinylated maltose binding protein was used for detecting specificity of IgG, the result shows a signal of bBSA layer in response to antibody is 5.8 × 10(-3) N/m compared to bMBP. The pre-functionalized biotin/PEG cantilever surface is found to show a long shelf-life of at least 40 days and retains its responsivity of above 70% of the signal when stored in PBS buffer at 4 °C. The protein cantilever biosensor represents a rapid, label-free, sensitive and reliable detection technique for a real-time protein assay.


Assuntos
Anticorpos/análise , Avidina/metabolismo , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/normas , Biotina/metabolismo , Animais , Antígenos/metabolismo , Biotinilação , Bovinos , Imunoglobulina G/análise , Camundongos , Padrões de Referência , Reprodutibilidade dos Testes , Soroalbumina Bovina/metabolismo
15.
S Afr J Infect Dis ; 38(1): 454, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36756241

RESUMO

Background: Experience from the Zaire Ebolavirus epidemic in the eastern Democratic Republic of the Congo (2018-2020) demonstrates that early initiation of essential critical care and administration of Zaire Ebolavirus specific monoclonal antibodies may be associated with improved outcomes among patients with Ebola virus disease (EVD). Objectives: This series describes 13 EVD patients and 276 patients with suspected EVD treated during a Zaire Ebolavirus outbreak in Guinea in 2021. Method: Patients with confirmed or suspected EVD were treated in two Ebola treatment centres (ETC) in the region of N'zérékoré. Data were reviewed from all patients with suspected or confirmed EVD hospitalised in these two ETCs during the outbreak (14 February 2021 - 19 June 2021). Ebola-specific monoclonal antibodies, were available 2 weeks after onset of the outbreak. Results: Nine of the 13 EVD patients (age range: 22-70 years) survived. The four EVD patients who died, including one pregnant woman, presented with multi-organ dysfunction and died within 48 h of admission. All eight patients who received Ebola-specific monoclonal antibodies survived. Four of the 13 EVD patients were health workers. Improvement of ETC design facilitated implementation of WHO-recommended 'optimized supportive care for EVD'. In this context, pragmatic clinical training was integrated in routine ETC activities. Initial clinical manifestations of 13 confirmed EVD patients were similar to those of 276 patients with suspected, but subsequently non confirmed EVD. These patients suffered from other acute infections (e.g. malaria in 183 of 276 patients; 66%). Five of the 276 patients with suspected EVD died. One of these five patients had Lassa virus disease and a coronavirus disease 2019 (COVID-19) co-infection. Conclusion: Multidisciplinary outbreak response teams can rapidly optimise ETC design. Trained clinical teams can provide WHO-recommended optimised supportive care, including safe administration of Ebola-specific monoclonal antibodies. Pragmatic training in essential critical care can be integrated in routine ETC activities. Contribution: This article describes clinical realities associated with implementation of WHO-recommended standards of 'optimized supportive care' and administration of Ebola virus specific treatments. In this context, the importance of essential design principles of ETCs is underlined, which allow continuous visual contact and verbal interaction of health workers and families with their patients. Elements that may contribute to further quality of care improvements for patients with confirmed or suspected EVD are discussed.

16.
Langmuir ; 28(15): 6494-501, 2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22439593

RESUMO

The accessibility and binding affinity of DNA are two key parameters affecting the hybridization efficiency in surface-based biosensor technologies. Better accessibility will result in a higher hybridization efficiency. Often, mixed ssDNA and mercaptohexanol monolayers are used to increase the hybridization efficiency and accessibility of surface-bound oligonucleotides to complementary target DNA. Here, no mercaptohexanol monolayer was used. We demonstrate by differential microcantilever deflection measurements at different pH that the hybridization efficiency peaks between pH 7.5 and 8.5. At low pH 4.5, hydration and electrostatic forces led to tensile surface stress, implying the reduced accessibility of the bound ssDNA probe for hybridization. In contrast, at high pH 8.5, the steric interaction between neighboring ssDNA strands was decreased by higher electrostatic repulsive forces, bending the microcantilever away from the gold surface to provide more space for the target DNA. Cantilever deflection scales with pH-dependent surface hybridization efficiency because of high target DNA accessibility. Hence, by changing the pH, the hybridization efficiency is adjusted.


Assuntos
DNA/química , Fenômenos Mecânicos , Nanotecnologia/métodos , Hibridização de Ácido Nucleico/métodos , Sequência de Bases , DNA/genética , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Concentração de Íons de Hidrogênio , Modelos Moleculares , Conformação de Ácido Nucleico , Propriedades de Superfície
17.
Biosensors (Basel) ; 12(11)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36354504

RESUMO

Sepsis is a life-threatening condition mostly caused by a bacterial infection resulting in inflammatory reaction and organ dysfunction if not treated effectively. Rapid identification of the causing bacterial pathogen already in the early stage of bacteremia is therefore vital. Current technologies still rely on time-consuming procedures including bacterial culturing up to 72 h. Our approach is based on ultra-rapid and highly sensitive nanomechanical sensor arrays. In measurements we observe two clearly distinguishable distributions consisting of samples with bacteria and without bacteria respectively. Compressive surface stress indicates the presence of bacteria. For this proof-of-concept, we extracted total RNA from EDTA whole blood samples from patients with blood-culture-confirmed bacteremia, which is the reference standard in diagnostics. We determined the presence or absence of bacterial RNA in the sample through 16S-rRNA hybridization and species-specific probes using nanomechanical sensor arrays. Via both probes, we identified two clinically highly-relevant bacterial species i.e., Escherichia coli and Staphylococcus aureus down to an equivalent of 20 CFU per milliliter EDTA whole blood. The dynamic range of three orders of magnitude covers most clinical cases. We correctly identified all patient samples regarding the presence or absence of bacteria. We envision our technology as an important contribution to early and sensitive sepsis diagnosis directly from blood without requirement for cultivation. This would be a game changer in diagnostics, as no commercial PCR or POCT device currently exists who can do this.


Assuntos
Bacteriemia , Sepse , Humanos , Ácido Edético , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Bactérias/genética , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Sepse/diagnóstico , Escherichia coli/genética
18.
EClinicalMedicine ; 54: 101699, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36263398

RESUMO

Background: As mortality remains high for patients with Ebola virus disease (EVD) despite new treatment options, the ability to level up the provided supportive care and to predict the risk of death is of major importance. This analysis of the EVISTA cohort aims to describe advanced supportive care provided to EVD patients in the Democratic Republic of the Congo (DRC) and to develop a simple risk score for predicting in-hospital death, called PREDS. Methods: In this prospective cohort (NCT04815175), patients were recruited during the 10th EVD outbreak in the DRC across three Ebola Treatment Centers (ETCs). Demographic, clinical, biological, virological and treatment data were collected. We evaluated factors known to affect the risk of in-hospital death and applied univariate and multivariate Cox proportional-hazards analyses to derive the risk score in a training dataset. We validated the score in an internal-validation dataset, applying C-statistics as a measure of discrimination. Findings: Between August 1st 2018 and December 31th 2019, 711 patients were enrolled in the study. Regarding supportive care, patients received vasopressive drug (n = 111), blood transfusion (n = 101), oxygen therapy (n = 250) and cardio-pulmonary ultrasound (n = 15). Overall, 323 (45%) patients died before day 28. Six independent prognostic factors were identified (ALT, creatinine, modified NEWS2 score, viral load, age and symptom duration). The final score range from 0 to 13 points, with a good concordance (C = 86.24%) and calibration with the Hosmer-Lemeshow test (p = 0.12). Interpretation: The implementation of advanced supportive care is possible for EVD patients in emergency settings. PREDS is a simple, accurate tool that could help in orienting early advanced care for at-risk patients after external validation. Funding: This study was funded by ALIMA.

19.
Glob Chall ; 5(2): 2000066, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33552553

RESUMO

The worldwide emergence of multidrug-resistant (MDR) bacteria is associated with significant morbidity, mortality, and healthcare costs. Rapid and accurate diagnostic methods to detect antibiotic resistance are critical for antibiotic stewardship and infection control measurements. Here a cantilever nanosensor-based diagnostic assay is shown to detect single nucleotide polymorphisms (SNPs) and genes associated with antibiotic resistance in Gram negative (Pseudomonas aeruginosa) and positive (Enterococcus faecium) bacteria, representing frequent causes for MDR infections. Highly specific RNA capture probes for SNPs (ampRD135G or ampRG154R ) or resistance genes (vanA, vanB, and vanD) allow to detect the binding of bacterial RNA within less than 5 min. Serial dilutions of bacterial RNA indicate an unprecedented sensitivity of 10 fg µL-1 total RNA corresponding to less than ten bacterial cells for SNPs and 1 fg µL-1 total RNA for vanD detection equivalent to single bacterial cell sensitivity.

20.
Andes Pediatr ; 92(6): 954-962, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35506809

RESUMO

The Surviving Sepsis Campaign International Guidelines for the Management of Septic Shock and Sepsis-associated Organ Dysfunction in Children was released in 2020 and is intended for use in all global settings that care for children with sepsis. However, practitioners managing children with sep sis in resource-limited settings (RLS) face several challenges and disease patterns not experienced by those in resource-rich settings. Based upon our collective experience from RLS, we aimed to reflect on the difficulties of implementing the international guidelines. We believe there is an urgent need for more evidence from RLS on feasible, efficacious approaches to the management of sepsis and septic shock that could be included in future context-specific guidelines.


Assuntos
Sepse , Choque Séptico , Criança , Cuidados Críticos , Cabeça , Humanos , Organizações , Sepse/diagnóstico , Sepse/terapia , Choque Séptico/diagnóstico , Choque Séptico/terapia
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