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Coronary heart disease (CHD) imposes a significant burden on health care systems because of high morbidity and mortality. There is documented evidence that South Asian people develop CHD at a higher rate and at an early age. If the affected individual is 40 years old or below, the tragic consequences are catastrophic. Identifying risk factors could be important for health promotion. The objectives of this study were to determine the frequency of risk factors in young patients with acute myocardial infarction and thus with ischemic heart disease (IHD) aged 40 years and below in our population. It was a descriptive observational study which was carried out at Coronary Care Unit of Rajshahi Medical college Hospital, Rajshahi, Bangladesh in 61 patients from January 2011 to June 2011. All patients who fulfilled the inclusion criteria admitted to coronary care unit (CCU) with a diagnosis of Acute MI were included. Their detailed history was then taken including symptoms at presentation and their risk factors were assessed according to the Framingham Risk Scoring System with the help of history and laboratory investigations. Mean age ±SD of the patients was 36±3.7 year. Most of the patients were male. Smoking was the major risk factor (73.8%) followed by family history of IHD (44.3%). Other risk factors were dyslipidaemia (39.35%), hypertension (37.7%), obesity (11.5%) and diabetes mellitus (8.2%). Majority of the patients were adopted in sedentary lifestyle. 91.8% patient presented with chest pain. Other symptoms were dyspnoea (37.7%), palpitation (59.0%), sweating (77.0%), nausea, vomiting (50.8%) and impaired consciousness (19.7%) etc. Most frequent risk factor for acute myocardial infarction (MI) at young age is smoking followed by family history of MI and dyslipidaemia. Majority of the patients had two or more than two identifiable antecedent risk factors.
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Infarto do Miocárdio , Isquemia Miocárdica , Humanos , Masculino , Adulto Jovem , Adulto , Feminino , Bangladesh/epidemiologia , Fatores de Risco , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Análise FatorialRESUMO
Using experiments and theory, we investigate the behavior of nonlinear acoustic modes in a physical system composed of an array of three coupled acoustic waveguides, two of which are externally driven with two different frequencies. Nonlinear modes with frequency given by linear combinations of the driving frequencies are realizations of so-called logical phi-bits. A phi-bit is a two-state degree of freedom of an acoustic wave, which can be in a coherent superposition of states with complex amplitude coefficients, i.e., a qubit analogue. We demonstrate experimentally that phi-bit modes are supported in the array of waveguides. Using perturbation theory, we show that phi-bits may result from the intrinsic nonlinearity of the material used to couple the waveguides. We have also isolated possible effects on phi-bit states associated with the systems' electronics, transducers and ultrasonic coupling agents used to probe the array and that may introduce extrinsic nonlinearities. These extrinsic effects are shown to be easily separable from the intrinsic behavior. The intrinsic behavior includes sharp jumps in phi-bit phases occurring over very narrow ranges of driving frequency. These jumps may also exhibit hysteretic behavior dependent on the direction of driving frequency tuning. The intrinsic states of phi-bits and multiple nonlinearly correlated phi-bits may serve as foundation for robust and practical quantum-analogue information technologies.
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Despite its success as an anticancer drug, cisplatin suffers from resistance and produces side effects. To overcome these limitations, amino-acid-linked cisplatin analogues have been investigated. Lysine-linked cisplatin, Lysplatin, (Lys)PtCl2, exhibited outstanding reactivity toward DNA and RNA that differs from that of cisplatin. To gain insight into its differing reactivity, the structure of Lysplatin is examined here using infrared multiple photon dissociation (IRMPD) action spectroscopy. To probe the influence of the local chemical environment on structure, the deprotonated and sodium-cationized Lysplatin complexes are examined. Electronic structure calculations are performed to explore possible modes of binding of Lys to Pt, their relative stabilities, and to predict their infrared spectra. Comparisons of the measured IRMPD and predicted IR spectra elucidate the structures contributing to the experimental spectra. Coexistence of two modes of binding of Lys to Pt is found where Lys binds via the backbone and side-chain amino nitrogen atoms, NNs, or to the backbone amino and carboxylate oxygen atoms, NO-. Glycine-linked cisplatin and arginine-linked cisplatin complexes have previously been found to bind only via the NO- binding mode. Present results suggest that the NNs binding conformers may be key to the outstanding reactivity of Lysplatin toward DNA and RNA.
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Lisina , Platina , Lisina/química , Cisplatino , Espectrofotometria Infravermelho/métodos , RNARESUMO
Adequate nutrition in early life is proposed to shape a child's future health by launching the growth trajectory in the proper direction, which helps to avoid negative metabolic programming effects. Protein intake during infancy and early childhood is of great importance, as it plays a key role in infant metabolic programming and the future risk of obesity. Breastfeeding provides the best nutrition in early life, with many benefits tailored for the baby, including the appropriate quantity and quality of proteins. Considering the high prevalence of childhood, and subsequent adult, obesity in the region, a virtual Middle East expert consensus meeting was held to discuss an effective approach for managing childhood obesity. Leading pediatric experts from Bahrain, Egypt, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates participated in the meeting. The experts discussed, debated, and agreed on certain directions, including the importance of educating parents, endorsing breastfeeding, and ensuring optimum quantity and quality intake of proteins in early life. This expert consensus may serve as the starting point for healthcare professionals in the region who are interested in shaping a healthy future for the generations to come.
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Results: Of 1,111 patients, 1,101 (99.1%) were included in the study. 589 (53.6%) patients were males. Median age at the time of endoscopy was 8 (interquartile range 3, 11) years. 1534 endoscopies were performed (1193 upper GI endoscopies (UGIE) and 341 colonoscopies) in 1296 sessions. The mean number of endoscopies per year was 59 ± 30.9 procedures with 81.4% reduction noted after coronavirus pandemic (P < 0.0001). Ratio between UGIE to colonoscopy was 3.5 : 1. Median number of endoscopies per patient was one, ranging from one to eight procedures. 1153 (89%) sessions were diagnostic, and 143 (11.0%) were therapeutic. Main endoscopic indication was chronic abdominal pain (451 (40.9%) patients) followed by upper GI bleeding (302 (27.4%) patients). Overall positive yield was 68.1% (716/1052 procedures). Endoscopic yield varies according to the type of procedure (P = 0.003). Colonoscopy alone gave a higher yield (82.6%, 38/46 procedures) compared to combined procedures (75.4%, 141/187) and UGIE alone (65.6%, 537/819). Conclusions: This study emphasizes a careful selection of the type of endoscopic procedures, based on the expected endoscopic yield, to diagnose and treat pediatric GI diseases. In patients with chronic abdominal pain, endoscopy should be reserved as a second-line tool to avoid unnecessary use of invasive procedures.
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Rapid spread of multidrug resistant microorganisms is a matter of great concern throughout the glove including Bangladesh. The objective was to identify the causative organisms for urinary tract infection (UTI) and their sensitivity patterns to antibiotics. This descriptive cross-sectional study was conducted on patients admitted with UTI (n=60) at a tertiary level hospital in Dhaka, Bangladesh from March 2019 to September 2019. Data were collected through clinical record reviews. Data of all these 60 cases were analyzed for socio-demographic characteristics. Of the 60 patients, culture and sensitivity report was available for 42 patients. Therefore, data were further analyzed for these 42 cases. Median age of patients was 35 years and 80% were female. The main organisms isolated from urine culture of UTI patients were E. coli (64%), Klebsiella (12%) and Enterococci species (10%). Susceptibility to antibiotics was analyzed only for E. coli (n=27) since the number of isolates of other organisms were small. E. coli was found to be resistant to most of the first- and second-line antibiotics, such as Amoxicillin (100%), Amoxyclav (72%), Co-trimoxazole (89%), Nalidixic acid (78%), Ceftazidim (94%), Ceftriaxone (73%), Cefuroxime (100%), Ciprofloxacin (59%), Cephotaxime (80%), Cefixime (100%) and Moxifloxacin (100%). E. coli was the predominant organism responsible for UTI and was resistant to most of the first- and second-line antibiotics. Immediate action is needed to develop empirical guideline for empirical management of UTI and establish surveillance system for monitoring.
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Escherichia coli , Infecções Urinárias , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bangladesh/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana , Feminino , Humanos , Testes de Sensibilidade Microbiana , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologiaRESUMO
MATERIALS AND METHODS: In this retrospective cross-sectional single center study, records of patients with esophageal strictures presented to the pediatric department, Salmaniya Medical Complex, Bahrain, in the period between 1995 and 2019 were reviewed. Demographic data, indications of endoscopic dilatations, the procedure success rate, and possible complications were assessed. RESULTS: Forty-six children were found to have esophageal strictures. Twenty-five (54.3%) patients were males. Most patients presented during infancy (86.5%, 32/37 patients). Twenty-six (56.5%) patients required 88 dilatation sessions, while the remaining 20 (43.5%) patients did not require dilatations. The median number of dilatation sessions per patient was three (interquartile range = 2-5). Savary-Gilliard bougienages were the main dilators used (80.8%, 21/26 patients). Anastomotic stricture (post esophageal atresia/tracheoesophageal fistula repair) was the main cause of esophageal strictures and was found in 35 (76.1%) patients. Patients with nonanastomotic strictures had more frequent dilatations compared to those with anastomotic strictures (P = 0.007). The procedure success rate was 98.8%. Yet, it was operator dependent (P = 0.047). Complete response to dilatation was found in 18 (69.2%) patients, satisfactory in seven (26.9%), and an inadequate response in one (3.9%). Those with satisfactory responses still require ongoing dilatations based on their symptoms and radiological and endoscopic findings. No perforation or mortality was reported. Patients with dilatations had more recurrent hospitalization (P < 0.0001), more dysphagia (P = 0.001), but shorter hospital stay (P = 0.046) compared to those without dilatations. Surgical intervention was required in one patient with caustic strictures. The median follow-up period was six years (interquartile range = 2.25-9.0). CONCLUSIONS: Endoscopic esophageal dilatation in children with esophageal strictures is effective and safe. Yet, it was operator dependent. Nonanastomotic strictures require more dilatations compared to anastomotic strictures. Findings of this study are comparable to those reported worldwide.
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The occurrence of functional gastrointestinal disorders (FGIDs) is a formidable challenge for infants, parents, and healthcare professionals. Although data from the Middle East are scarce, experts consider FGIDs a prevalent condition in everyday clinical practice. The new Rome IV criteria revisited the definitions from a clinical perspective to provide a practical and consistent diagnostic protocol for FGIDs. However, the treatment practices for functional disorders vary considerably among Middle Eastern countries, often resulting in mismanagement with unnecessary investigations and treatments. In addition, the role of various treatment modalities, including probiotics such as Lactobacillus reuteri DSM 17938, in FGIDs requires further discussion and evaluation. During a consensus meeting, a locally relevant approach for treating common FGIDs such as infant regurgitation, infant colic, and functional constipation was discussed and approved by regional experts. The participants suggested a simplified treatment plan and protocol for general pediatricians and other primary care physicians managing FGIDs. This easy-to-follow standardized protocol will help streamline the initial management of this complex disorder in the Middle East region and even globally.
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Hepatitis A virus (HAV) is the most common cause of acute viral hepatitis in the world. Infection with hepatitis A virus can cause severe or even fatal illness in patients with chronic liver disease. Here we present a case which seems to be an isolated acute viral hepatitis A infection at the beginning but later found to be coexisted with Wilson's disease. A 14-year-old girl presented in the Department of Gastroenterology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh on 11th April 2019 with progressive jaundice with prodrome, dark urine, itching, hepatomegaly and thyromegaly. She was found positive for serum IgM HAV antibody. Her jaundice was increasing along with prolonged prothrombin time and low albumin. She had coexisting Wilson's disease evidenced by increased 24 hours urinary copper (138µgm/day). She was treated with D-Penicillamine and Zinc acetate. Hepatitis A can be considered as a factor for acute decompensation in undiagnosed patients with Wilson's disease. So it is very crucial to investigate Wilson's disease in appropriate clinical setting of prolonged jaundice and liver dysfunction.
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Vírus da Hepatite A , Hepatite A , Degeneração Hepatolenticular , Icterícia , Adolescente , Bangladesh , Cobre , Feminino , Hepatite A/complicações , Hepatite A/diagnóstico , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/diagnóstico , Degeneração Hepatolenticular/tratamento farmacológico , Humanos , Icterícia/diagnóstico , Icterícia/etiologia , PenicilaminaRESUMO
We demonstrate theoretically, using multiple-time-scale perturbation theory, the existence of nonseparable superpositions of elastic waves in an externally driven elastic system composed of three one-dimensional elastic wave guides coupled via nonlinear forces. The nonseparable states span a Hilbert space with exponential complexity. The amplitudes appearing in the nonseparable superposition of elastic states are complex quantities dependent on the frequency of the external driver. By tuning these complex amplitudes, we can navigate the state's Hilbert space. This nonlinear elastic system is analogous to a two-partite two-level quantum system.
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Mycobacteria are subdivided into three groups: the Mycobacterium tuberculosis complex, the non-tuberculous mycobacteria called NTM or MOTT (Mycobacteria Other Than Tuberculosis) and Mycobacterium leprae. Over the past few decades, the incidence of infections caused by NTM has increased world wide. The differentiation of Mycobacterium tuberculosis complex from NTM is of primary importance for infection control and choice of antimicrobial therapy. However, there is so far no report in Bangladesh about the detection of NTM and hence differentiation of MTB and NTM. Neither acid-fast bacilli (AFB) staining nor histopathology can discriminate MTB and NTM. In order to detect and differentiate Mycobacterium tuberculosis complex and NTM we used commercially available LyteStar TB/NTM Real Time PCR kit (Altona Diagnostics, Germany) and analyzed 782 clinical specimens from tuberculosis suspected patients. We have found 49 MTB and 74 NTM positive samples from variety of clinical specimens such as sputum, bronchial lavages, body fluids, tissues, needle aspirates and swabs. Many of the PCR positive specimens were AFB negative on direct microscopic examination thus, indicating strong sensitivity of PCR than AFB staining. This is the first report in the country about detection of NTM and it warrants further elaborate investigation. Moreover, our results showed that multiplex real-time PCR assay is an effective sensitive tool for the rapid identification and differentiation of MTB and NTM directly from clinical specimens.
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Mycobacterium tuberculosis , Micobactérias não Tuberculosas , Reação em Cadeia da Polimerase em Tempo Real , Bangladesh , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Tuberculose/diagnósticoRESUMO
BACKGROUND: Renal cell carcinoma (RCC) is a seventh ranked malignancy with poor prognosis. RCC is lethal at metastatic stage as it does not respond to conventional systemic treatments, and there is an urgent need to find out promising novel biomarkers for effective treatment. The goal of this study was to evaluate the biomarkers that can be potential therapeutic target and predict effective inhibitors to treat the metastatic stage of RCC. METHODS: We conducted transcriptomic profiling to identify differentially expressed genes associated with RCC. Molecular pathway analysis was done to identify the canonical pathways and their role in RCC. Tissue microarrays (TMA) based immunohistochemical stains were used to validate the protein expression of cyclinD1 (CCND1) and were scored semi-quantitatively from 0 to 3+ on the basis of absence or presence of staining intensity in the tumor cell. Statistical analysis determined the association of CCND1 expression with RCC. Molecular docking analyses were performed to check the potential of two natural inhibitors, rutin and curcumin to bind CCND1. RESULTS: We detected 1490 significantly expressed genes (1034, upregulated and 456, downregulated) in RCC using cutoff fold change 2 and p value < 0.05. Hes-related family bHLH transcription factor with YRPW motif 1 (HEY1), neuropilin 2 (NRP2), lymphoid enhancer-binding factor 1 (LEF1), and histone cluster 1 H3h (HIST1H3H) were most upregulated while aldolase B, fructose-bisphosphate (ALDOB), solute carrier family 12 (SLC12A1), calbindin 1 (CALB1) were the most down regulated genes in our dataset. Functional analysis revealed Wnt/ß-catenin signaling as the significantly activated canonical pathway (z score = 2.53) involving cyclin D1 (CCND1). CCND1 was overexpressed in transcriptomic studies (FC = 2.26, p value = 0.0047) and TMA results also showed the positive expression of CCND1 in 53 % (73/139) of RCC cases. The ligands - rutin and curcumin bounded with CCND1 with good affinity. CONCLUSION: CCND1 was one of the important upregulated gene identified in microarray and validated by TMA. Docking study showed that CCND1 may act as a potential therapeutic target and its inhibition could focus on the migratory, invasive, and metastatic potential of RCC. Further in vivo and in vitro molecular studies are needed to investigate the therapeutic target potential of CCND1 for RCC treatment.
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Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Ciclina D1/metabolismo , Perfilação da Expressão Gênica/métodos , Neoplasias Renais/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Análise por Conglomerados , Ciclina D1/análise , Ciclina D1/genética , Humanos , Neoplasias Renais/genética , Simulação de Acoplamento Molecular , Arábia Saudita , Análise Serial de TecidosRESUMO
The aim of this review is to define the incidence of renal dysfunction among pediatric liver transplant (LT) survivors, to identify the associated risk factors and to outline the therapeutic options. Renal dysfunction is a common problem after pediatric LT. The measured glomerular filtration rate is considered the "gold-standard" for assessment of renal function. Renal dysfunction in pediatric LT recipients is multifactorial. Renal-sparing immunosuppressive strategies are essential to reverse renal dysfunction and to prevent end-stage renal disease.
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Doença Hepática Terminal/cirurgia , Taxa de Filtração Glomerular/fisiologia , Transplante de Fígado/efeitos adversos , Criança , Humanos , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Fatores de RiscoRESUMO
OBJECTIVE: The aim of this study was to test how the presence of central neuropathic pain (CNP) influences the performance of a motor imagery based Brain Computer Interface (BCI). METHODS: In this electroencephalography (EEG) based study, we tested BCI classification accuracy and analysed event related desynchronisation (ERD) in 3 groups of volunteers during imagined movements of their arms and legs. The groups comprised of nine able-bodied people, ten paraplegic patients with CNP (lower abdomen and legs) and nine paraplegic patients without CNP. We tested two types of classifiers: a 3 channel bipolar montage and classifiers based on common spatial patterns (CSPs), with varying number of channels and CSPs. RESULTS: Paraplegic patients with CNP achieved higher classification accuracy and had stronger ERD than paraplegic patients with no pain for all classifier configurations. Highest 2-class classification accuracy was achieved for CSP classifier covering wider cortical area: 82±7% for patients with CNP, 82±4% for able-bodied and 78±5% for patients with no pain. CONCLUSION: Presence of CNP improves BCI classification accuracy due to stronger and more distinct ERD. SIGNIFICANCE: Results of the study show that CNP is an important confounding factor influencing the performance of motor imagery based BCI based on ERD.
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Interfaces Cérebro-Computador , Imagens, Psicoterapia/métodos , Atividade Motora/fisiologia , Neuralgia/fisiopatologia , Neuralgia/psicologia , Paraplegia/fisiopatologia , Paraplegia/psicologia , Adulto , Mapeamento Encefálico , Comorbidade , Sincronização Cortical/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Pé/inervação , Pé/fisiologia , Mãos/inervação , Mãos/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiologia , Neuralgia/epidemiologia , Paraplegia/epidemiologiaRESUMO
The purpose of this study was to investigate the effects of T-wave amplitude and ECG lead on beat-to-beat QT interval variability (QTV) in patients with myocardial infarction (MI) compared to healthy subjects. Standard resting 12-lead ECGs of 79 MI patients and 69 healthy subjects were investigated. Beat-to-beat QT intervals were measured separately for each lead using a template matching algorithm. In addition, we extracted the beat-to-beat T-wave amplitude in each lead. We computed the standard deviation of beat-to-beat QT intervals as a marker of QTV for both healthy subjects and MI patients. Significant QTV differences were observed between the 12 ECG leads as well as between the groups of healthy subjects and MI patients. Beat-to-beat QTV was significantly higher in MI patients than in healthy subjects for half of the leads. Furthermore, significant T-wave amplitude differences across leads and between groups were observed. A significant inverse relation between beat-to-beat QTV and T-wave amplitude was demonstrated. The group differences in QTV remained significant after co-varying for the T-wave amplitude. In conclusion, the increase in beat-to-beat QTV that has been repeatedly reported in patients with MI is partly due to the lower T-wave amplitudes. However, QTV remains significantly increased in MI patients after covarying for this effect.
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Eletrocardiografia , Infarto do Miocárdio/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROCRESUMO
BACKGROUND AND OBJECTIVES: The Gleason grading of prostate carcinoma (PCa) in needle core biopsies is a major determinant used in management planning. The objective of this study was to evaluate the concordance between general pathologists Gleason grading and that of a urologic pathologist in our community. DESIGN AND SETTING: Retrospective review conducted at three tertiary care hospitals in Jeddah and Riyadh for all prostatic biopsies with carcinoma from January 2002 to January 2011. METHODS: Gleason scores assigned by the original pathologist were compared with that of the reviewing urologic pathologists. Biopsies were originally obtained and diagnosed at different referring hospitals and independent laboratories. The kappa test was used to evaluate agreement between the original and review scores. RESULTS: For 212 biopsies the exact concordance of the Gleason score assigned by the original pathologist and the reviewer was 38.7% (82/212). However, when grouped into the main four-score categories of 2-4, 5-6, 7, and 8 or greater, disagreement was noted in 88 (41.5%) biopsies; 87 were upgraded and 1 was downgraded on review. When grouped into two-score categories of low grade (≤6) and high grade (≥7), disagreement was noted in 32 (15%) of the biopsies. CONCLUSION: Gleason grade score shows that there was only slight to fair agreement between outside and review scoring (kappa=0.43). When using only low versus high grade categorization, there was good agreement (kappa=0.69). Almost all of the cases with score disagreement were upgraded on review.
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Carcinoma/patologia , Gradação de Tumores/estatística & dados numéricos , Variações Dependentes do Observador , Próstata/patologia , Neoplasias da Próstata/patologia , Biópsia por Agulha , Humanos , Masculino , Patologia , Estudos Retrospectivos , UrologiaRESUMO
Multispectral three-dimensional (3D) imaging provides spatial information for biological structures that cannot be measured by traditional methods. This work presents a method of tracking 3D biological structures to quantify changes over time using graph theory. Cell-graphs were generated based on the pairwise distances, in 3D-Euclidean space, between nuclei during collagen I gel compaction. From these graphs quantitative features are extracted that measure both the global topography and the frequently occurring local structures of the "tissue constructs." The feature trends can be controlled by manipulating compaction through cell density and are significant when compared to random graphs. This work presents a novel methodology to track a simple 3D biological event and quantitatively analyze the underlying structural change. Further application of this method will allow for the study of complex biological problems that require the quantification of temporal-spatial information in 3D and establish a new paradigm in understanding structure-function relationships.
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Técnicas de Cultura de Células/métodos , Imageamento Tridimensional/métodos , Células-Tronco Mesenquimais/citologia , Modelos Biológicos , Contagem de Células , Colágeno Tipo I/farmacologia , Fluorescência , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Microscopia Confocal , Fatores de TempoRESUMO
Fetal electrocardiogram (FECG) signal contains potentially precise information that could assist clinicians in making more appropriate and timely decisions during labor. The ultimate reason for the interest in FECG signal analysis is in clinical diagnosis and biomedical applications. The extraction and detection of the FECG signal from composite abdominal signals with powerful and advance methodologies are becoming very important requirements in fetal monitoring. The purpose of this review paper is to illustrate the various methodologies and developed algorithms on FECG signal detection and analysis to provide efficient and effective ways of understanding the FECG signal and its nature for fetal monitoring. A comparative study has been carried out to show the performance and accuracy of various methods of FECG signal analysis for fetal monitoring. Finally, this paper further focused some of the hardware implementations using electrical signals for monitoring the fetal heart rate. This paper opens up a passage for researchers, physicians, and end users to advocate an excellent understanding of FECG signal and its analysis procedures for fetal heart rate monitoring system.
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This paper presents a comprehensive study in recovery of Cr (VI) from dilute HCl solution using liquid emulsion membrane (LEM). The liquid membrane is made up of Tri-octylphosphine oxide (TOPO) as a carrier, cyclohexane as an organic diluent, sodium hydroxide as a stripping solution and Span-80 (sorbitain monooleate) as an emulsifying agent. The selection of the extractant (TOPO) and the stripper (NaOH) was chosen on the basis of conventional liquid-liquid extraction studies. The important parameters affecting the permeation of Cr (VI) through the prepared membrane are hydrogen ion concentration in the external aqueous phase, stirring speed of mixing the two phases, type of diluents, carrier concentration, stripper concentration, membrane to feed ratio and volume fraction were systematically investigated. The effect of surfactant types and concentration on the stability of LEM were studied because of its important role in the permeation process.
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Cromo/isolamento & purificação , Emulsões , Membranas Artificiais , Água/química , SoluçõesRESUMO
The extraction equilibrium of Gd(III) from nitrate medium by 8-hydroxyquinoline (HOX) in toluene was studied. Liquid-liquid investigations were first carried out. Based on the equilibrium results, the extraction of Gd(III) from aqueous nitrate medium into an emulsion liquid membrane system (ELM) containing 8-hydroxyquinoline in toluene as extractant, HNO(3) as stripping solution, Span-80 as surfactant was studied. The stability of the prepared ELM was studied in terms of the degree of membrane breakage. The different parameters affecting the permeation of gadolinium (III) were also studied. A general permeation model for the recovery of Gd(III) by the selected membrane is presented. The internal mass transfer in the water in oil (W/O) emulsion drop, the external mass transfer around the drop, the rates of formation and decomposition of the complex at the external aqueous-organic interface were considered.