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1.
Sci Rep ; 12(1): 7936, 2022 05 13.
Article in English | MEDLINE | ID: mdl-35562409

ABSTRACT

The emergence of carbapenemase-producing multi-drug resistant Enterobacteriaceae poses a dramatic, world-wide health risk. Limited treatment options and a lack of easy-to-use methods for the detection of infections with multi-drug resistant bacteria leave the health-care system with a fast-growing challenge. Aptamers are single stranded DNA or RNA molecules that bind to their targets with high affinity and specificity and can therefore serve as outstanding detection probes. However, an effective aptamer selection process is often hampered by non-specific binding. When selections are carried out against recombinant proteins, purification tags (e.g. polyhistidine) serve as attractive side targets, which may impede protein target binding. In this study, aptamer selection was carried out against N-terminally hexa-histidine tagged New Delhi metallo-ß-lactamase 1. After 14 selection rounds binding to polyhistidine was detected rather than to New Delhi metallo-ß-lactamase 1. Hence, the selection strategy was changed. As one aptamer candidate showed remarkable binding affinity to polyhistidine, it was used as a masking probe and selection was restarted from selection round 10. Finally, after three consecutive selection rounds, an aptamer with specific binding properties to New Delhi metallo-ß-lactamase 1 was identified. This aptamer may serve as a much-needed detection probe for New Delhi metallo-ß-lactamase 1 expressing Enterobacteriaceae.


Subject(s)
Histidine , Anti-Bacterial Agents , beta-Lactamases/genetics
2.
Microorganisms ; 9(8)2021 Aug 13.
Article in English | MEDLINE | ID: mdl-34442806

ABSTRACT

Anti-SARS-CoV-2 spike RBD (receptor-binding domain) IgG antibody levels were monitored in 1643 volunteer healthcare workers of Eginition, Evangelismos, and Konstantopoulio General Hospitals (Athens, Greece), who underwent vaccination with two doses of COVID-19 BNT162b2 mRNA vaccine (Pfizer) and had no history of SARS-CoV-2 infection. Venous blood was collected 20-30 days after the second vaccine dose and anti-RBD IgG levels were determined using CMIA SARS-CoV-2 IgG II Quant (Abbott) on ARCHITECT i System or ADVIA Centaur SARS-CoV-2 IgG (Siemens) on Centaur XP platform. From the total population of 1643 vaccinees (533 M/1110 F; median age = 49; interquartile range-IQR = 40-56), 1636 (99.6%) had anti-SARS-CoV-2 IgG titers above the positivity threshold of the assay used. One-Way ANOVA Kruskal-Wallis H test showed a statistically significant difference in the median of antibody titers between the different age groups (p < 0.0001). Consistently, Spearman's correlation coefficient (r) for IgGs and age as continuous variables was -0.2380 (p = 1.98 × 10-17). Moreover, antibody titers were slightly higher by 1.2-mean fold (p = 3 × 10-6) in the total female population of the three hospitals (median = 1594; IQR = 875-2584) as compared to males (median = 1292; IQR = 671.9-2188). The present study supports that BNT162b2 vaccine is particularly effective in producing high anti-SARS-CoV-2 IgG levels in healthy individuals, and this humoral response is age- and gender-dependent.

3.
Vet Parasitol ; 233: 32-38, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-28043385

ABSTRACT

Trypanosoma congolense and T. vivax are the main causative agents of animal African trypanosomosis (AAT), a disease which hinders livestock production throughout sub-Saharan Africa and in some parts of South America. Although two trypanocidal drugs are currently available, the level of treatment is low due to the difficulty in diagnosing the disease in the field. The major clinical signs of AAT such as anaemia, weight loss, and infertility, are common to several other endemic livestock diseases. Current diagnostic methods, based on the visualization of the parasite in the blood, or on the detection of its DNA or the antibodies it triggers in the host, are not suitable for direct use in the field as they require specialized equipment and personnel. Thus, we developed a quick-format diagnostic test (15min) based on the recombinant TcoCB and TvGM6 antigens for detection of T. congolense and T. vivax, respectively, aimed at providing farmers and veterinarians in the field with the means to conduct a quick diagnosis. The specificity and sensitivity of the test were evaluated using sera from experimentally infected cattle, and fresh blood when possible. The prototype, which includes both antigens, shows a specificity of 95.9 (95% C.I., 90.4%-100%) and a sensitivity of 92.0% (95% C.I., 85.9%-98.1%) for T. congolense and 98.2% (95% C.I., 94.7%-100%) for T. vivax. The high levels of sensitivity and specificity of this rapid test, the possibility of using directly whole blood, and the ease of interpreting the result, all contribute to make of this test a valuable candidate to contribute to the control of AAT in the field. However, further tests with more representative, numerous and fresh reference samples are necessary in order to compare this test with the ELISA, the current gold standard serological test for trypanosomosis.


Subject(s)
Cattle Diseases/diagnosis , Serologic Tests/veterinary , Trypanosomiasis, African/veterinary , Africa South of the Sahara , Animals , Antigens, Protozoan/metabolism , Cattle , Point-of-Care Systems , Sensitivity and Specificity , Serologic Tests/standards , Time Factors , Trypanosomiasis, African/diagnosis
4.
J Relig Health ; 56(2): 521-529, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27146050

ABSTRACT

This paper aims to investigate the stress management skills of Christian Orthodox monks and nuns, as measured by Antonovsky's scale sense of coherence (SOC). A case-control study was designed to test the hypotheses whether monks and nuns have higher SOC than secular people. The study population consisted of 193 individuals, 96 monks and nuns (study group) and 97 secular men and women (control group). SOC score was higher in monks and nuns as compared to the secular population (p = 0.002), men as compared to women (p = 0.012) and persons of older age (p = 0.004) as compared to younger individuals.


Subject(s)
Christianity/psychology , Monks/psychology , Nuns/psychology , Religion and Psychology , Sense of Coherence , Stress, Psychological/psychology , Adult , Case-Control Studies , Female , Greece , Humans , Male , Sex Distribution , Surveys and Questionnaires
5.
Ophthalmol Eye Dis ; 7: 7-12, 2015.
Article in English | MEDLINE | ID: mdl-26106264

ABSTRACT

INTRODUCTION: Music has been proposed as a safe, inexpensive, nonpharmacological antistress intervention. The purpose of this study was to determine whether patients undergoing cataract surgery while listening to meditation music experience lower levels of blood pressure and heart rate. METHODS: Two hundred individuals undergoing cataract surgery participated in the study. Hundred individuals listened to meditation music, through headphones, before and during the operation (intervention group) and 100 individuals received standard care (control group). Patients stress coping skills were measured by the Sense of Coherence Scale (SOC Scale). Systolic and diastolic blood pressure and heart rate were defined as outcome measures. RESULTS: According to the SOC Scale, both groups had similar stress coping skills (mean score: 127.6 for the intervention group and 127.3 for the control group). Before entering the operating room (OR) as well as during surgery the rise in systolic and diastolic pressures was significantly lower in the intervention group (P < 0.001). Among patients receiving antihypertensive therapy, those in the intervention group presented a lower increase only in systolic pressure (P < 0.001) at both time recordings. For those patients in the intervention group who did not receive antihypertensive treatment, lower systolic blood pressure at both time recordings was recorded (P < 0.001) while lower diastolic pressure was observed only during entry to the OR (P = 0.021). Heart rate was not altered between the two groups in any of the recordings. CONCLUSIONS: Meditation music influenced patients' preoperative stress with regard to systolic blood pressure. This kind of music can be used as an alternative or complementary method for blood pressure stabilizing in patients undergoing cataract surgery.

6.
Asian Cardiovasc Thorac Ann ; 22(9): 1072-9, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24637028

ABSTRACT

BACKGROUND: We aimed to consolidate our clinical observations regarding the development of pulmonary hypertension following pneumonectomy for lung cancer. METHODS: Sixty-nine of 82 initially selected patients without pulmonary or cardiac comorbidities, who underwent pneumonectomy for lung cancer between October 2009 and October 2011, accomplished our protocol. Mean patient age was 60.6 years (range 44-78 years) and 10.1% were women. RESULTS: Postoperative complications occurred in 16 (23.2%) patients. Mortality at 1, 12, and 18 months postoperatively was 4.3%, 15.9%, and 29%, respectively. One year postoperatively, 37.9% of patients developed mild to moderate pulmonary hypertension and 3.4% had severe pulmonary hypertension. The calculated mean pulmonary artery systolic pressure at 1, 6, and 12 months postoperatively was 21.9 ± 6.6, 27.3 ± 9.3, and 34.1 ± 14 mm Hg, respectively (p < 0.001). Receiver operating characteristic curve analysis showed a cutoff point at 35.5 mm Hg for late postoperative (at 12 months) pulmonary artery systolic pressure (sensitivity 80%, specificity 82%; p < 0.001) related to suboptimal clinical outcomes (decreased performance status or death), with a detected 18-fold risk for these patients (p < 0.001). CONCLUSIONS: Pulmonary hypertension may occur after pneumonectomy with its known adverse effects. Patients with late postoperative pulmonary artery systolic pressure > 35.5 mm Hg are at higher risk of a suboptimal clinical outcome.


Subject(s)
Hypertension, Pulmonary/epidemiology , Lung Neoplasms/surgery , Pneumonectomy/methods , Postoperative Complications/epidemiology , Adult , Aged , Cohort Studies , Female , Humans , Lung/surgery , Lung Neoplasms/epidemiology , Male , Middle Aged , Prospective Studies , ROC Curve , Retrospective Studies , Sensitivity and Specificity , Treatment Outcome
7.
Int J Neural Syst ; 23(5): 1350022, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23924413

ABSTRACT

In this paper, we investigate the indirect adaptive regulation problem of unknown affine in the control nonlinear systems. The proposed approach consists of choosing an appropriate system approximation model and a proper control law, which will regulate the system under the certainty equivalence principle. The main difference from other relevant works of the literature lies in the proposal of a potent approximation model that is bilinear with respect to the tunable parameters. To deploy the bilinear model, the components of the nonlinear plant are initially approximated by Fuzzy subsystems. Then, using appropriately defined fuzzy rule indicator functions, the initial dynamical fuzzy system is translated to a dynamical neuro-fuzzy model, where the indicator functions are replaced by High Order Neural Networks (HONNS), trained by sampled system data. The fuzzy output partitions of the initial fuzzy components are also estimated based on sampled data. This way, the parameters to be estimated are the weights of the HONNs and the centers of the output partitions, both arranged in matrices of appropriate dimensions and leading to a matrix to matrix bilinear parametric model. Based on the bilinear parametric model and the design of appropriate control law we use a Lyapunov stability analysis to obtain parameter adaptation laws and to regulate the states of the system. The weight updating laws guarantee that both the identification error and the system states reach zero exponentially fast, while keeping all signals in the closed loop bounded. Moreover, introducing a method of "concurrent" parameter hopping, the updating laws are modified so that the existence of the control signal is always assured. The main characteristic of the proposed approach is that the a priori experts information required by the identification scheme is extremely low, limited to the knowledge of the signs of the centers of the fuzzy output partitions. Therefore, the proposed scheme is not vulnerable to initial design assumptions. Simulations on selected examples of well-known benchmarks illustrate the potency of the method.


Subject(s)
Algorithms , Fuzzy Logic , Neural Networks, Computer , Nonlinear Dynamics , Animals , Humans
8.
Int J Neural Syst ; 22(2): 1250004, 2012 Apr.
Article in English | MEDLINE | ID: mdl-23627590

ABSTRACT

In this paper we analyze the identification problem which consists of choosing an appropriate identification model and adjusting its parameters according to some adaptive law, such that the response of the model to an input signal (or a class of input signals), approximates the response of the real system for the same input. For identification models we use fuzzy-recurrent high order neural networks. High order networks are expansions of the first-order Hopfield and Cohen-Grossberg models that allow higher order interactions between neurons. The underlying fuzzy model is of Mamdani type assuming a standard defuzzification procedure such as the weighted average. Learning laws are proposed which ensure that the identification error converges to zero exponentially fast or to a residual set when a modeling error is applied. There are two core ideas in the proposed method: (1) Several high order neural networks are specialized to work around fuzzy centers, separating in this way the system into neuro-fuzzy subsystems, and (2) the use of a novel method called switching parameter hopping against the commonly used projection in order to restrict the weights and avoid drifting to infinity.


Subject(s)
Fuzzy Logic , Learning/physiology , Neural Networks, Computer , Neurons/physiology , Nonlinear Dynamics , Algorithms , Computer Simulation , Humans
9.
World J Gastrointest Oncol ; 2(8): 311-21, 2010 Aug 15.
Article in English | MEDLINE | ID: mdl-21160892

ABSTRACT

Capecitabine (Xeloda(®)) is an oral fluoropyrimidine which is produced as a pro-drug of fluorouracil, and shows improved tolerability and intratumor drug concentrations following its tumor-specific conversion to the active drug. We have searched the Pubmed and Cochrane databases from 1980 to 2009 with the purpose of reviewing all available information on Capecitabine, focusing on its clinical effectiveness against colorectal cancer. Special attention has been paid to trials that compared Capecitabine with standard folinic acid (leucovorin, LV)-modulated intravenous 5-fluorouracil (5-FU) bolus regimens in patients with metastatic colorectal cancer. Moreover the efficacy of Capecitabine on metastatic colorectal cancer, either alone or in various combinations with other active drugs such as Irinotecan and Oxaliplatin was also assessed. Finally, neoadjuvant therapy consisting of Capecitabine plus radiation therapy, for locally advanced rectal cancer was analysed. This combination of chemotherapy and radiotherapy has a special role in tumor down staging and in sphincter preservation for lower rectal tumors. Comparative trials have shown that Capecitabine is at least equivalent to the standard LV-5-FU combination in relation to progression-free and overall survival whilst showing a better tolerability profile with a much lower incidence of stomatitis. It is now known that Capecitabine can be combined with other active drugs such as Irinotecan and Oxaliplatin. The combination of Oxaliplatin with Capecitabine represents a new standard of care for metastatic colorectal cancer. Combinating the Capecitabine-Oxaliplatin regimen with promising new biological drugs such as Bevacizumab seems to give a realistic prospect of further improvement in time to progression of metastatic disease. Moreover, preoperative chemo-radiation using oral capecitabine is better tolerated than bolus 5-FU and is more effective in the promotion of both down-staging and sphincter preservation in patients with locally advanced rectal cancer. Finally, the outcomes of recently published trials suggest that capecitabine seems to be more cost effective than other standard treatments for the management of patients with colorectal cancer.

10.
Int J Neural Syst ; 20(4): 319-39, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20726041

ABSTRACT

The direct adaptive regulation of unknown nonlinear dynamical systems in Brunovsky form with modeling error effects, is considered in this paper. Since the plant is considered unknown, we propose its approximation by a special form of a Brunovsky type neuro-fuzzy dynamical system (NFDS) assuming also the existence of disturbance expressed as modeling error terms depending on both input and system states plus a not-necessarily-known constant value. The development is combined with a sensitivity analysis of the closed loop and provides a comprehensive and rigorous analysis of the stability properties. The existence and boundness of the control signal is always assured by introducing a novel method of parameter hopping and incorporating it in weight updating laws. Simulations illustrate the potency of the method and its applicability is tested on well known benchmarks, as well as in a bioreactor application. It is shown that the proposed approach is superior to the case of simple recurrent high order neural networks (HONN's).


Subject(s)
Algorithms , Neural Networks, Computer , Nonlinear Dynamics , Fuzzy Logic , Mathematics
11.
Int J Neural Syst ; 20(2): 129-48, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20411596

ABSTRACT

The indirect adaptive regulation of unknown nonlinear dynamical systems with multiple inputs and states (MIMS) under the presence of dynamic and parameter uncertainties, is considered in this paper. The method is based on a new neuro-fuzzy dynamical systems description, which uses the fuzzy partitioning of an underlying fuzzy systems outputs and high order neural networks (HONN's) associated with the centers of these partitions. Every high order neural network approximates a group of fuzzy rules associated with each center. The indirect regulation is achieved by first identifying the system around the current operation point, and then using its parameters to device the control law. Weight updating laws for the involved HONN's are provided, which guarantee that, under the presence of both parameter and dynamic uncertainties, both the identification error and the system states reach zero, while keeping all signals in the closed loop bounded. The control signal is constructed to be valid for both square and non square systems by using a pseudoinverse, in Moore-Penrose sense. The existence of the control signal is always assured by employing a novel method of parameter hopping instead of the conventional projection method. The applicability is tested on well known benchmarks.


Subject(s)
Adaptation, Physiological/physiology , Fuzzy Logic , Neural Networks, Computer , Nonlinear Dynamics , Uncertainty , Algorithms , Humans , Pattern Recognition, Automated/methods
12.
Berl Munch Tierarztl Wochenschr ; 120(1-2): 50-60, 2007.
Article in German | MEDLINE | ID: mdl-17290943

ABSTRACT

In Germany, the application of antimicrobial agents represents the method of choice to control infections of food-producing animals by bacteria of the genus Leptospira. However, only few data are available on the susceptibility of Leptospira spp. against antimicrobial agents and the in vivo efficacy of antimicrobial agents. Based on a modified broth microdilution method, a standardised in-vitro susceptibility testing system for Leptospira spp. was established which also included quality control aspects. Considering the minimum inhibitory concentrations determined in this study in-vivo efficacy is expected for the following classes of antimicrobial agents: penicillins, cephalosporins, macrolides, lincosamides, fluoroquinolones, phenicols, and in part also for aminoglycosides and tetracyclines. Clinical aspects and bioavailability of the drugs in the target tissues have to be taken into account. Penicillins and aminoglycosides as commonly used inhibitory supplements in semen extender seem to be effective against leptospires.


Subject(s)
Anti-Bacterial Agents/pharmacology , Indicator Dilution Techniques/veterinary , Leptospira/isolation & purification , Leptospirosis/veterinary , Animals , Consumer Product Safety , Culture Media , Dose-Response Relationship, Drug , Leptospirosis/diagnosis , Meat/microbiology , Meat/standards , Microbial Sensitivity Tests/veterinary , Quality Control , Reproducibility of Results
13.
Rev Cubana Med Trop ; 57(1): 49-50, 2005.
Article in English | MEDLINE | ID: mdl-17966478

ABSTRACT

A multi-serovar ELISA based on the outer membrane Lipoprotein L41 (LipL41) of pathogenic Leptospira was developed to increase sensitivity by using a single test antigen. A sensitivity of 99 % and a specifity of 92 % could be achieved. The established diagnostic polymerase chain reaction is also able to detect fast and reliably pathogenic Leptospira in different clinical samples.


Subject(s)
Enzyme-Linked Immunosorbent Assay/veterinary , Leptospira/isolation & purification , Leptospirosis/veterinary , Polymerase Chain Reaction/veterinary , Swine Diseases/diagnosis , Animals , Enzyme-Linked Immunosorbent Assay/methods , Gerbillinae , Leptospira/genetics , Leptospira/pathogenicity , Leptospirosis/diagnosis , Polymerase Chain Reaction/methods , Sensitivity and Specificity , Swine
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