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1.
Cureus ; 16(6): e63445, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39077306

RESUMO

Recent studies suggest a role for anthocyanins in the treatment of non-alcoholic fatty liver disease (NAFLD). The purpose of the present review was to assess the effect of anthocyanins as an adjuvant treatment in patients with NAFLD. The literature search was conducted on MEDLINE/PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), the Web of Science, and Scopus without language or time limits up to March 27, 2024. The primary outcomes included the severity of liver fibrosis and the level of liver transaminases. Secondary outcomes included obesity and lipid profile assessments. Standardized mean differences (SMDs) with 95% CIs were calculated for numerical outcomes. Five studies were included. The pooled effect sizes showed lower levels of liver fibrosis and liver transaminases in the anthocyanin group, but the difference was nonsignificant and small in size. The same result was obtained with anthropometric measurements of total cholesterol, low-density lipoprotein, and serum triglycerides, where effect sizes ranged from negligible to medium in magnitude but were all nonsignificant. The anthocyanin group showed a significantly lower body fat percentage (SMD = -0.41 (95%CI: -0.76; -0.06), P = 0.021). Currently, no evidence is available on the efficacy of anthocyanins in improving liver fibrosis or dyslipidemia in patients with NAFLD. There is limited evidence that anthocyanins can lower body fat percentages, but the effect was not reflected in the pooled results of other obesity indices. The few available clinical trials showed several limitations and variations regarding the doses of anthocyanins. Future clinical trials should avoid the limitations of the current studies and provide evidence supporting or refuting the use of anthocyanins in NAFLD patients.

2.
Virus Genes ; 60(1): 80-96, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38079060

RESUMO

Diabetic patients are more susceptible to developing wound infections resulting in poor and delayed wound healing. Bacteriophages, the viruses that target-specific bacteria, can be used as an alternative to antibiotics to eliminate drug-resistant bacterial infections. Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) are among the most frequently identified pathogens in diabetic foot ulcers (DFUs). The aim of this study was assessment of bacteriophage and gentamicin combination effects on bacterial isolates from DFU infections. Specific bacteriophages were collected from sewage and animal feces samples and the phages were enriched using S. aureus and P. aeruginosa cultures. The lytic potential of phage isolates was assessed by the clarity of plaques. We isolated and characterized four lytic phages: Stp2, Psp1, Stp1, and Psp2. The phage cocktail was optimized and investigated in vitro. We also assessed the effects of topical bacteriophage cocktail gel on animal models of DFU. Results revealed that the phage cocktail significantly reduced the mortality rate in diabetic infected mice. We determined that treatment with bacteriophage cocktail effectively decreased bacterial colony counts and improved wound healing in S. aureus and P. aeruginosa infections, especially when administrated concomitantly with gentamicin. The application of complementary therapy using a phage cocktail and gentamicin, could offer an attractive approach for the treatment of wound diabetic bacterial infections.


Assuntos
Bacteriófagos , Diabetes Mellitus , Infecções por Pseudomonas , Infecções Estafilocócicas , Humanos , Camundongos , Animais , Staphylococcus aureus , Pseudomonas aeruginosa , Gentamicinas/farmacologia , Gentamicinas/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções por Pseudomonas/terapia , Infecções por Pseudomonas/microbiologia , Modelos Animais de Doenças , Diabetes Mellitus/tratamento farmacológico
3.
Hum Fertil (Camb) ; 26(6): 1617-1635, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37791451

RESUMO

Infertility is an important issue among couples worldwide which is caused by a variety of complex diseases. Male infertility is a problem in 7% of all men. In vitro spermatogenesis (IVS) is the experimental approach that has been developed for mimicking seminiferous tubules-like functional structures in vitro. Currently, various researchers are interested in finding and developing a microenvironmental condition or a bioartificial testis applied for fertility restoration via gamete production in vitro. The tissue engineering (TE) has developed new approaches to treat male fertility preservation through development of functional male germ cells. This makes TE a possible future strategy for restoration of male fertility. Although 3D culture systems supply the perception of the effect of cellular interactions in the process of spermatogenesis, formation of a native gradient of autocrine/paracrine factors in 3D culture systems have not been considered. These results collectively suggest that maintaining the microenvironment of testicular cells even in the form of a 3D-culture system is crucial in achieving spermatogenesis ex vivo. It is also possible to engineer the testicular structures using biomaterials to provide a supporting scaffold for somatic and stem cells. The insemination of these cells with GFs is possible for temporally and spatially adjusted release to mimic the microenvironment of the in situ seminiferous epithelium. This review focuses on recent studies and advances in the application of TE strategies to cell-tissue culture on synthetic or natural scaffolds supplemented with growth factors.


Assuntos
Infertilidade Masculina , Engenharia Tecidual , Masculino , Humanos , Testículo , Túbulos Seminíferos/metabolismo , Espermatogênese/fisiologia , Infertilidade Masculina/terapia
4.
J Funct Biomater ; 14(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37754867

RESUMO

The gastrointestinal tract (GIT) environment has an intricate and complex nature, limiting drugs' stability, oral bioavailability, and adsorption. Additionally, due to the drugs' toxicity and side effects, renders are continuously seeking novel delivery systems. Lipid-based drug delivery vesicles have shown various loading capacities and high stability levels within the GIT. Indeed, most vesicular platforms fail to efficiently deliver drugs toward this route. Notably, the stability of vesicular constructs is different based on the different ingredients added. A low GIT stability of liposomes and niosomes and a low loading capacity of exosomes in drug delivery have been described in the literature. Bilosomes are nonionic, amphiphilic, flexible surfactant vehicles that contain bile salts for the improvement of drug and vaccine delivery. The bilosomes' stability and plasticity in the GIT facilitate the efficient carriage of drugs (such as antimicrobial, antiparasitic, and antifungal drugs), vaccines, and bioactive compounds to treat infectious agents. Considering the intricate and harsh nature of the GIT, bilosomal formulations of oral substances have a remarkably enhanced delivery efficiency, overcoming these conditions. This review aimed to evaluate the potential of bilosomes as drug delivery platforms for antimicrobial, antiviral, antifungal, and antiparasitic GIT-associated drugs and vaccines.

5.
J Biomol Struct Dyn ; : 1-14, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37288800

RESUMO

Chlamydia trachomatis (C. trachomatis) is an obligate intracellular bacterium which causes eye and sexually transmitted infections. During pregnancy, the bacterium is associated with preterm complications, low weight of neonates, fetal demise and endometritis leading to infertility. The aim of our study was design of a multi-epitope vaccine (MEV) candidate against C. trachomatis. After protein sequence adoption from the NCBI, potential epitopes toxicity, antigenicity, allergenicity, MHC-I and MHC-II binding, cytotoxic T lymphocytes (CTLs), Helper T lymphocytes (HTLs) and interferon-γ (IFN-γ)- induction were predicted. The adopted epitopes were fused together using appropriate linkers. In the next step, the MEV structural mapping and characterization, three-dimensional (3D) structure homology modeling and refinement were also performed. The MEV candidate interaction with the toll-like receptor 4 (TLR4) was also docked. The immune responses simulation was assessed using the C-IMMSIM server. Molecular dynamic (MD) simulation verified the structural stability of the TLR4-MEV complex. The Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) approach demonstrated the MEV high affinity of binding to the TLR4, MHC-I and MHC-II. The MEV construct was also stable and water soluble and had enough antigenicity and lacked allergenicity with stimulation of T cells and B cells and INF-γ release. The immune simulation confirmed acceptable responses of both the humoral and cellular arms. It is proposed that in vitro and in vivo studies are needed to evaluate the findings of this study.Communicated by Ramaswamy H. Sarma.

6.
Arch Microbiol ; 205(6): 252, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249707

RESUMO

Inflammatory bowel disease (IBD) is a chronic recurrent inflammation of the gastrointestinal tract (GIT). IBD patients are susceptible to various infections such as viral infections due to the long-term consumption of immunosuppressive drugs and biologics. The antiviral and IBD protective traits of flavonoids have not been entirely investigated. This study objective included an overview of the protective role of flavonoids quercetin and silymarin in viral-associated IBD. Several viral agents such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella zoster virus (VZV) and enteric viruses can be reactivated and thus develop or exacerbate the IBD conditions or eventually facilitate the disease remission. Flavonoids such as quercetin and silymarin are non-toxic and safe bioactive compounds with remarkable anti-oxidant, anti-inflammatory and anti-viral effects. Mechanisms of anti-inflammatory and antiviral effects of silymarin and quercetin mainly include immune modulation and inhibition of caspase enzymes, viral binding and replication, RNA synthesis, viral proteases and viral assembly. In the nutraceutical sector, natural flavonoids low bioavailability and solubility necessitate the application of delivery systems to enhance their efficacy. This review study provided an updated understanding of the protective role of quercetin and silymarin against viral-associated IBD.


Assuntos
Infecções por Vírus Epstein-Barr , Doenças Inflamatórias Intestinais , Silimarina , Humanos , Herpesvirus Humano 4/genética , Quercetina/farmacologia , Silimarina/farmacologia , Flavonoides , Doenças Inflamatórias Intestinais/tratamento farmacológico , Antivirais/farmacologia , Antivirais/uso terapêutico
7.
J Environ Manage ; 328: 116966, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36521222

RESUMO

An understanding of traditional ecological knowledge systems is increasingly acknowledged as a means of helping to develop global, regional and national, but locally relevant policies. Pastoralists often use lands that are unsuitable for crops due to biophysical and climatic extremities and variabilities. Forage plants of pastures are utilized by herding communities by applying locally relevant multigenerational knowledge. We analyzed the forage-related knowledge of pastoralists and herders by reviewing scientific papers and video documentaries on forage plants and indicators, their use in land management, and plant-livestock interactions. Semi-structured interviews were also conducted with key knowledge holders in Iran, Mongolia, Kenya, Poland and Hungary. We found 35 indicators used by herders to describe forage species. The indicators described botanical features, livestock behavior during grazing, and the impact of plants on livestock condition and health. The indicators were used in context-specific management decisions, with a variety of objectives to optimize grazing. We identified ten global principles, including, among others, a livestock-centered perspective, close monitoring and targeted pasturing of various (preferred or avoided) forages, and the use of different livestock types and well-planned spatial movements at multiple scales to optimize the utilization of available plant resources. Although pastoralists vary greatly across the globe, the character and use of their traditional forage-related knowledge do seem to follow strikingly similar principles. Understanding these may help the local-to-global-level understanding of these locally specific systems, support bottom-up pastoral initiatives and discussions on sustainable land management, and help to develop locally relevant global and national policies.


Assuntos
Conservação dos Recursos Naturais , Gado , Animais , Ecossistema , Produtos Agrícolas , Hungria
8.
Antibiotics (Basel) ; 11(9)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36139986

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) has evolved vast antibiotic resistance. These strains contain numerous virulence factors facilitating the development of severe infections. Considering the costs, side effects, and time duration needed for the synthesis of novel drugs, seeking efficient alternative approaches for the eradication of drug-resistant bacterial agents seems to be an unmet requirement. Nickel nanoparticles (NiNPs) have been applied as prognostic and therapeutic cheap agents to various aspects of biomedical sciences. Their antibacterial effects are exerted via the disruption of the cell membrane, the deformation of proteins, and the inhibition of DNA replication. NiNPs proper traits include high-level chemical stability and binding affinity, ferromagnetic properties, ecofriendliness, and cost-effectiveness. They have outlined pleomorphic and cubic structures. The combined application of NiNPs with CuO, ZnO, and CdO has enhanced their anti-MRSA effects. The NiNPs at an approximate size of around 50 nm have exerted efficient anti-MRSA effects, particularly at higher concentrations. NiNPs have conferred higher antibacterial effects against MRSA than other nosocomial bacterial pathogens. The application of green synthesis and low-cost materials such as albumin and chitosan enhance the efficacy of NPs for therapeutic purposes.

9.
PLoS One ; 17(8): e0272582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36040967

RESUMO

Hepatitis C virus (HCV) infects the liver and causes chronic infection. Several mutations in the viral genome have been associated with drug resistance development. Currently, there is no approved vaccine against the HCV. The employment of computational biology is the primary and crucial step for vaccine design or antiviral therapy which can substantially reduce the duration and cost of studies. Therefore, in this study, we designed a multi-epitope vaccine using various immunoinformatics tools to elicit the efficient human immune responses against the HCV. Initially, various potential (antigenic, immunogenic, non-toxic and non-allergenic) epitope segments were extracted from viral structural and non-structural protein sequences using multiple screening methods. The selected epitopes were linked to each other properly. Then, toll-like receptors (TLRs) 3 and 4 agonists (50S ribosomal protein L7/L12 and human ß-defensin 2, respectively) were added to the N-terminus of the final vaccine sequence to increase its immunogenicity. The 3D structure of the vaccine was modeled. Molecular dynamics simulations studies verified the high stability of final free vaccines and in complex with TLR3 and TLR4. These constructs were also antigenic, non-allergenic, nontoxic and immunogenic. Although the designed vaccine traits were promising as a potential candidate against the HCV infection, experimental studies and clinical trials are required to verify the protective traits and safety of the designed vaccine.


Assuntos
Hepacivirus , Hepatite C , Sequência de Aminoácidos , Biologia Computacional/métodos , Epitopos de Linfócito B , Epitopos de Linfócito T , Hepacivirus/genética , Hepatite C/prevenção & controle , Humanos , Simulação de Acoplamento Molecular , Vacinas de Subunidades Antigênicas
10.
Environ Res ; 212(Pt B): 113269, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35427594

RESUMO

Black carbon (BC) is a product of incomplete combustion, present in urban aerosols and sourcing mainly from road traffic. Epidemiological evidence reports positive associations between BC and cardiovascular and respiratory disease. Despite this, BC is currently not regulated by the EU Air Quality Directive, and as a result BC data are not available in urban areas from reference air quality monitoring networks in many countries. To fill this gap, a machine learning approach is proposed to develop a BC proxy using air pollution datasets as an input. The proposed BC proxy is based on two machine learning models, support vector regression (SVR) and random forest (RF), using observations of particle mass and number concentrations (N), gaseous pollutants and meteorological variables as the input. Experimental data were collected from a reference station in Barcelona (Spain) over a 2-year period (2018-2019). Two months of additional data were available from a second urban site in Barcelona, for model validation. BC concentrations estimated by SVR showed a high degree of correlation with the measured BC concentrations (R2 = 0.828) with a relatively low error (RMSE = 0.48 µg/m3). Model performance was dependent on seasonality and time of the day, due to the influence of new particle formation events. When validated at the second station, performance indicators decreased (R2 = 0.633; RMSE = 1.19 µg/m3) due to the lack of N data and PM2.5 and the smaller size of the dataset (2 months). New particle formation events critically impacted model performance, suggesting that its application would be optimal in environments where traffic is the main source of ultrafine particles. Due to its flexibility, it is concluded that the model can act as a BC proxy, even based on EU-regulatory air quality parameters only, to complement experimental measurements for exposure assessment in urban areas.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono , Monitoramento Ambiental , Dinâmica não Linear , Material Particulado/análise , Fuligem/análise
11.
Andrologia ; 49(5)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27484294

RESUMO

Association of hepatitis C virus (HCV) with autoimmune phenomena and impaired semen parameters has been previously reported. The aim of this study was to investigate the influence of HCV infection on the development of antisperm antibodies (ASAs) in HCV-positive males. The study was conducted on 30 HCV-infected individuals and 30 healthy control subjects. In both patients and control groups, liver enzymes and reproductive hormones were measured; computer-assisted semen analysis (CASA) was performed; HCV-RNA in serum was measured and IgG and IgA ASAs in semen were determined. Free testosterone, sperm concentration, progressive and total motility were significantly lower in HCV patients than in the control group, whereas ASAs of the IgG and IgA classes were significantly higher in HCV patients. However, correlations between viral load and the examined semen parameters and ASAs were nonsignificant. In conclusion, HCV may be responsible for the increased ASAs detected in HCV patients in the present study, possibly providing another plausible explanation for the decreased sperm motility reported in HCV patients. These findings could be of value in fertility management of HCV patients.


Assuntos
Autoanticorpos/análise , Hepatite C/imunologia , Espermatozoides/imunologia , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Egito , Hepatite C/fisiopatologia , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Masculino , Pessoa de Meia-Idade , Sêmen/imunologia , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Carga Viral
12.
IEEE Trans Nanobioscience ; 15(6): 533-548, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27824576

RESUMO

Unlike normal diffusion, in anomalous diffusion, the movement of a molecule is described by the correlated random walk model where the mean square displacement of a molecule depends on the power law of time. In molecular communication (MC), there are many scenarios when the propagation of molecules cannot be described by normal diffusion process, where anomalous diffusion is a better fit. In this paper, the effects of anomalous subdiffusion on concentration-encoded molecular communication (CEMC) are investigated. Although classical (i.e., normal) diffusion is a widely-used model of diffusion in molecular communication (MC) research, anomalous subdiffusion is quite common in biological media involving bio-nanomachines, yet inadequately addressed as a research issue so far. Using the fractional diffusion approach, the molecular propagation effects in the case of pure subdiffusion occurring in an unbounded three-dimensional propagation medium have been shown in detail in terms of temporal dispersion parameters of the impulse response of the subdiffusive channel. Correspondingly, the bit error rate (BER) performance of a CEMC system is investigated with sampling-based (SD) and strength (i.e., energy)-based (ED) signal detection methods. It is found that anomalous subdiffusion has distinctive time-dispersive properties that play a vital role in accurately designing a subdiffusive CEMC system. Unlike normal diffusion, to detect information symbols in subdiffusive CEMC, a receiver requires larger memory size to operate correctly and hence a more complex structure. An in-depth analysis has been made on the performances of SD and ED optimum receiver models under diffusion noise and intersymbol interference (ISI) scenarios when communication range, transmission data rate, and memory size vary. In subdiffusive CEMC, the SD method.


Assuntos
Biotecnologia , Difusão , Modelos Teóricos , Nanotecnologia , Espaço Intracelular/química , Espaço Intracelular/metabolismo , Nanoestruturas
13.
Environ Manage ; 56(3): 721-37, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25957624

RESUMO

Understanding the perception of environmental resources by the users is an important element in planning its sustainable use and management. Pastoralist communities manage their vast grazing territories and exploit resource variability through strategic mobility. However, the knowledge on which pastoralists' resource management is based and their perception of the grazing areas has received limited attention. To improve this understanding and to document this knowledge in a way that can be communicated with 'outsiders', we adopted a participatory mapping approach using satellite imagery to explore how Borana pastoralists of southern Ethiopia differentiated and characterized their grazing areas. The Borana herders conceptualized their grazing areas as set of distinctive grazing units each having specific names and characteristics. The precise location and the borders of each grazing unit were identified on the satellite image. In naming of the grazing units, the main differentiating criteria were landforms, vegetation types, prevalence of wildlife species, and manmade features. Based on the dominant soil type, the grazing units were aggregated into seasonal grazing areas that were described using factors such as soil drainage properties, extent of woody cover, main grass species, and prevalence of ecto-parasites. Pastoralists ranking of the seasonal grazing areas according to their suitability for cattle grazing matched with vegetation assessment results on the abundance of desirable fodder varieties. Approaching grazing area differentiation from the pastoralists' perspectives improves the understanding of rangeland characteristics that pastoralists considered important in their grazing management and visualization of their mental representation in digital maps eases communication of this knowledge.


Assuntos
Criação de Animais Domésticos/métodos , Conservação dos Recursos Naturais/métodos , Fazendeiros , Mapeamento Geográfico , Herbivoria , Percepção , Animais , Bovinos , Etiópia , Fazendeiros/psicologia , Poaceae/crescimento & desenvolvimento , Inquéritos e Questionários , Abastecimento de Água
14.
IEEE Trans Nanobioscience ; 14(1): 67-83, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25594973

RESUMO

In this paper, a comprehensive analysis of strength-based optimum signal detection model has been presented for concentration-encoded molecular communication (CEMC) with spike (i.e., impulsive) transmission based on amplitude-shift keying (ASK) and on-off keying (OOK) modulations. Strength-based optimum signal detection problem in diffusion-based CEMC system has been investigated in detail in the presence of both diffusion noise and intersymbol interference (ISI). The receiver for optimum signal detection has been developed theoretically and explained with both analytical and simulation results of binary signal detection. Results show that the receiver thus developed can detect CEMC symbols effectively; however, the performance is influenced by three main factors, namely, communication range, transmission data rate, and receiver memory. For both ASK and OOK receivers, exact and approximate detection performances have been derived analytically depending on the probabilistic nature of molecular availability and the relationship between mean and variance of signal strengths. Correspondingly, bit error rate (BER) performance of the optimum receiver in a single CEMC link is further evaluated under various scenarios through extensive simulation experiments.


Assuntos
Modelos Teóricos , Processamento de Sinais Assistido por Computador , Simulação por Computador
15.
Andrologia ; 47(5): 587-93, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25130880

RESUMO

The aim of this study was to examine whether an association exists between glutathione S-transferase Mu-1 (GSTM1) gene polymorphism and idiopathic male infertility. Sixty men with primary idiopathic infertility and 60 fertile men, serving as controls, were recruited for the study. The polymorphism was analysed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The frequency of GSTM1 null genotype was observed to be higher in infertile men 40% in comparison with 33.3% in the fertile men, but this difference was not statistically significant. There was statistically significant difference between cases and controls as regards GSTM1 genotype distribution ((MC) P = 0.006*) in GSTM1-positive men. Patients with the GSTM1 null genotype had significantly lower sperm concentrations and total sperm count when compared with patients with GSTM1-positive genotype. In the control group, men with GSTM1 null genotype had significantly lower sperm concentrations but not total sperm count when compared with men with GSTM1-positive genotype. The results of this study suggest a possible negative effect of GSTM1 null genotype on the spermatogenic potential of the testis.


Assuntos
Glutationa Transferase/genética , Infertilidade Masculina/genética , Espermatogênese/genética , Adulto , Egito , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Contagem de Espermatozoides
16.
IEEE Trans Nanobioscience ; 13(3): 208-22, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25163066

RESUMO

In this paper, a comprehensive analysis of the sampling-based optimum signal detection in ideal (i.e., free) diffusion-based concentration-encoded molecular communication (CEMC) system has been presented. A generalized amplitude-shift keying (ASK)-based CEMC system has been considered in diffusion-based noise and intersymbol interference (ISI) conditions. Information is encoded by modulating the amplitude of the transmission rate of information molecules at the TN. The critical issues involved in the sampling-based receiver thus developed are addressed in detail, and its performance in terms of the number of samples per symbol, communication range, and transmission data rate is evaluated. ISI produced by the residual molecules deteriorates the performance of the CEMC system significantly, which further deteriorates when the communication range and/or the transmission data rate increase(s). In addition, the performance of the optimum receiver depends on the receiver's ability to compute the ISI accurately, thus providing a trade-off between receiver complexity and achievable bit error rate (BER). Exact and approximate detection performances have been derived. Finally, it is found that the sampling-based signal detection scheme thus developed can be applied to both binary and multilevel (M-ary) ASK-based CEMC systems, although M-ary systems suffer more from higher BER.


Assuntos
Comunicação , Computadores Moleculares , Processamento de Sinais Assistido por Computador , Biotecnologia , Simulação por Computador , Modelos Teóricos , Nanotecnologia
18.
Gait Posture ; 35(3): 494-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22153769

RESUMO

During leg flexion from erect posture, postural stability along the medio-lateral direction is organized in advance during "anticipatory postural adjustments" (APAs). This study aimed to investigate the influence of temporal pressure on this anticipatory postural control of medio-lateral stability. Eight young healthy participants performed series of leg flexions (1) as soon as possible in response to an acoustic signal (reaction-time condition; condition with temporal pressure) and (2) in a self-initiated condition (no temporal pressure). Results showed that APAs duration was shorter in the reaction-time condition as compared to the self-initiated condition; this shortening was compensated by an increase in the medio-lateral center-of-pressure displacement so that the dynamic stability reached at foot-off, as measured by the "extrapolated center-of-mass", remained unchanged. It is concluded that when a complex task is performed under temporal pressure, the central nervous system is able to modulate the spatio-temporal features of APAs in a way to both hasten the initiation of the voluntary movement and maintain optimal conditions of dynamic stability. In other words, it seems that the central nervous system does not "trade off optimal stability for speed of movement initiation under reaction-time condition", as it had been proposed in the literature.


Assuntos
Equilíbrio Postural/fisiologia , Amplitude de Movimento Articular/fisiologia , Tempo de Reação , Análise de Variância , Fenômenos Biomecânicos , Eletromiografia/métodos , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Movimento/fisiologia , Percepção/fisiologia , Postura/fisiologia , Valores de Referência , Estudos de Amostragem , Adulto Jovem
19.
Andrologia ; 43(1): 16-22, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21219377

RESUMO

The aim of this study was to assess the prevalence of Δ-F508 mutation and 5T allele in a sample of Egyptian patients having congenital bilateral absent vas deferens (CBAVD), to correlate between genotype and phenotypic genital pattern, and to demonstrate the value of micro-assisted reproduction in them. The study included thirty patients with CBAVD and 30 fertile controls. Clinical, laboratory and radiological examinations of the patients were performed. Genetic assessment of patients and controls as regards Δ-F508 mutation and 5T allele was done. Trials of testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI) were carried out for the patients. Δ-F508 mutation was present in 40% and 5T allele was detected in 46.6% of the patients. On the other hand, all the control group was negative as regards Δ-F508 mutation, while 5T allele was detected in 10% of them. The total fertilisation rate was 75% and pregnancy rate was 60% with no significant difference in fertilisation and pregnancy rates between cases positive for Δ-F508 or 5T allele and others. It is evident that Δ-F508 mutation and 5T allele play important roles in the pathogenesis of CBAVD in Egyptians. TESE/ICSI is a beneficial method to enable these patients to father children of their own.


Assuntos
Alelos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Mutação/genética , Fenótipo , Ducto Deferente/anormalidades , Adulto , Estudos de Casos e Controles , Egito/epidemiologia , Aconselhamento Genético , Genótipo , Humanos , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/genética , Infertilidade Masculina/terapia , Masculino , Pessoa de Meia-Idade , Prevalência , Injeções de Esperma Intracitoplásmicas/métodos , Recuperação Espermática
20.
J Eur Acad Dermatol Venereol ; 24(11): 1340-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20337814

RESUMO

BACKGROUND: Livedoid vasculopathy (LV) is a chronic idiopathic disease characterized by painful purpuric macules on lower extremities. Its exact aetiology remains uncertain, but thrombotic and microcirculatory phenomena have been implicated as possible pathogenic factors. OBJECTIVES: To assess prospectively the frequency of thrombophilia and to verify the effectiveness of anticoagulant therapy among LV patients. METHODS: Thirty-four LV patients were tested for prothrombin time, activated partial thromboplastin time, antithrombin activity, protein C and S activity, anticardiolipin antibodies, lupus anticoagulant, prothrombin gene mutation, factor V Leiden mutation, methylenetetrahydrofolate reductase mutation, plasma homocysteine and fibrinogen. Thirteen of these patients were treated with anticoagulant drugs (either warfarin or heparin). RESULTS: Of 34 patients, 18 (52%) presented laboratory abnormalities of procoagulant conditions. Positive treatment response to anticoagulant therapy was observed in 11 patients. Improvement of pain was obtained in 1-3 weeks, an average of 1.8 week. Complete healing of the lesions was observed in about 2.3 months. Remission was sustained even after treatment interruption and lasted an average 7.8 months. No severe adverse effects were noticed. CONCLUSION: The authors suggest all patients with diagnosis of LV to be investigated for thrombophilic status. Anticoagulant drugs were well tolerated and seemed to be effective in treating not only LV symptoms but also its ulcerations.


Assuntos
Anticoagulantes/uso terapêutico , Dermatopatias Vasculares , Trombofilia , Varfarina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Anticardiolipina/sangue , Testes de Coagulação Sanguínea , Fator V/genética , Feminino , Fibrinogênio/metabolismo , Heparina/uso terapêutico , Homocisteína/sangue , Humanos , Inibidor de Coagulação do Lúpus/sangue , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Estudos Prospectivos , Proteína C/metabolismo , Proteína S/metabolismo , Protrombina/genética , Dermatopatias Vasculares/tratamento farmacológico , Dermatopatias Vasculares/epidemiologia , Dermatopatias Vasculares/genética , Trombofilia/tratamento farmacológico , Trombofilia/epidemiologia , Trombofilia/genética , Adulto Jovem
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