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1.
Heliyon ; 10(12): e33021, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39022065

RESUMEN

This article describes the design and fabrication of a 4 × 4 MIMO antenna array intended for operation at 60 GHz. The antenna comprises of half-circular p-shaped radiator connected with a microstrip line printed on the Rogers 4003 substrate of area 22.5 × 22.5 mm2 with εr, thickness, and tan Î´ of 3.5, 0.203 mm, and 0.0027, respectively. This single radiator is doubled and connected to the power divider to obtain a 1 × 2 antenna array for gain enhancement purposes. The array model is duplicated on the same substrate to achieve 2 ports and 4 ports MIMO antenna. Thereafter, the model is experimentally fabricated and tested to validate the simulated results. The measured results demonstrate the antenna's 60 GHz operating bandwidth extended from 57 GHz to 63 GHz and with insertion losses ≤ -30 dB between ports (1,2) and (1,4) (the orthogonal ports), while it equals around ≤ -23 dB between ports (1,3) (the mirrored ports) within the achieved band with good consistency between both simulated and tested results. Also, it has achieved a gain of more than 9 dBi at 60 GHz with a broadside radiation pattern in both planes. Furthermore, the MIMO parameters are also carried out (ECC, DG, CCL, MEG, and TARC). The ECC is below 0.0025, the DG is approximately 10 dB, the CCL is below 0.2 bits/s/Hz, the MEG is -3 dB and the TARC is below -10 dB over the achieved frequency band. All the MIMO parameters are investigated to prove the diversity characteristics of the antenna array which supports the antenna to be suitable for the 60 GHz communication.

2.
Micromachines (Basel) ; 14(7)2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37512620

RESUMEN

A circularly polarized (CP) and wide-band monopole antenna with a miniaturized size is suggested in this study. The suggested structure is composed of a U-shaped radiator on the front side, a partial ground plane with two rectangle slots, and a quadrilateral-shaped parasitic strip on the back side of the FR4 substrate. A wide-band operation with S11 ≤ -10 dB was achieved by regulating the radiator and the partial ground that was placed on the second side of the antenna substrate. The CP was achieved when excited two modes with the same amplitude and a 90° phase difference. This could be generated by regulating the slots' dimensions in the ground plane. Moreover, a quadrilateral-shaped parasitic strip placed on the second side with the partial ground was utilized to extend the 3 dB axial ratio (AR) bandwidth. The suggested structure is simulated, prototyped, and measured to confirm the desired requirements with a total size of 30 × 32 mm2 (0.4 × 0.42 λ0 at 4 GHz). The tested outcomes have a bandwidth of S11 ≤ -10 dB (81.25%) (5.2 GHz, 3.8-9 GHz) and a 3 dB axial ratio (AR) bandwidth (30.7%) (1.63 GHz, 4.48-6.11 GHz). The antenna's different parameters are discussed, which recommend the suggested antenna to be used in UWB, sub 6 GHz, and WLAN wireless applications.

3.
Sci Rep ; 11(1): 19758, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34611216

RESUMEN

Chronic obstructive pulmonary disease (COPD) is characterised by the occurrence of exacerbations triggered by infections. The aim of this study was to determine the composition of the lung microbiome and lung virome in patients with COPD in an African setting and to compare their composition between the stable and exacerbated states. Twenty-four adult COPD patients were recruited from three hospitals. Sputum was collected and bacterial DNA was extracted. Targeted metagenomics was performed to determine the microbiome composition. Viral DNA and RNA were extracted from selected samples followed by cDNA conversion. Shotgun metagenomics sequencing was performed on pooled DNA and RNA. The most abundant phyla across all samples were Firmicutes and Proteobacteria. The following genera were most prevalent: Haemophilus and Streptococcus. There were no considerable differences for alpha and beta diversity measures between the disease states. However, a difference in the abundances between disease states was observed for: (i) Serratia (3% lower abundance in exacerbated state), (ii) Granulicatella (2.2% higher abundance in exacerbated state), (iii) Haemophilus (5.7% higher abundance in exacerbated state) and (iv) Veillonella (2.5% higher abundance in exacerbated state). Virome analysis showed a high abundance of the BeAn 58058 virus, a member of the Poxviridae family, in all six samples (90% to 94%). This study is among the first to report lung microbiome composition in COPD patients from Africa. In this small sample set, no differences in alpha or beta diversity between stable and exacerbated disease state was observed, but an unexpectedly high frequency of BeAn 58058 virus was observed. These observations highlight the need for further research of the lung microbiome of COPD patients in African settings.


Asunto(s)
Pulmón/microbiología , Microbiota , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/etiología , Anciano , Biodiversidad , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Metagenoma , Metagenómica , Persona de Mediana Edad , Factores de Riesgo , Sudáfrica/epidemiología , Esputo/microbiología
4.
J Physiol Pharmacol ; 72(2)2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34642258

RESUMEN

Although there is accumulating evidence which suggests that the administration of ghrelin could be used to preserve cardiac function, delay the progression of heart failure post-myocardial infarction, and attenuate ventricular remodeling, there is still no definitive data that clearly highlights the mechanisms by which ghrelin exerts cardioprotective effects. The present study aimed to investigate whether ghrelin could affect nuclear factor erythroid 2-related factor-2 (Nrf2), heme oxygenase-1 (HO-1), and endothelial nitric oxide synthase (eNOS) expression and exert anti-inflammatory as well as antioxidant-like actions through this signaling pathway. Rats were assorted into four groups with 10 in each: Group I (Control), Group II (received ghrelin only), Group III (MI was induced by isoproterenol (ISO)), Group IV (MI was induced by isoproterenol and within 30 min of each ISO dose, rats received ghrelin; 100 µg /kg subcutaneously two times per day). We assessed the effects of acylated ghrelin on the biochemical changes, ECG parameters, heart rate, histopathological scoring and the mRNA expression of eNOS, Nrf2 (confirmed immunohistochemically) as well as HO-1 genes in the cardiac tissues. Nuclear factor-κB, tumor necrosis factor-α, interleukin-6, and inducible nitric oxide synthase were assessed as inflammatory markers. Ghrelin markedly improved the oxidative stress injury and inflammation, showed histological preservation of the cardiac muscle fibers morphology, ameliorated the ISO-induced ECG changes and caused a significant elevation in eNOS, HO-1, and Nrf2 expression. In conclusion, ghrelin exerts cardioprotective effect in ISO-induced myocardial infarction by promoting the eNOS/Nrf2/HO-1 pathway.


Asunto(s)
Infarto del Miocardio , Factor 2 Relacionado con NF-E2 , Animales , Ghrelina/metabolismo , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Isoproterenol/metabolismo , Infarto del Miocardio/inducido químicamente , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Estrés Oxidativo , Ratas , Transducción de Señal
5.
Surg Oncol ; 38: 101637, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34358880

RESUMEN

BACKGROUND: Compared to open surgery, minimally invasive liver resection has improved short term outcomes. It is however technically more challenging. Navigated image guidance systems (IGS) are being developed to overcome these challenges. The aim of this systematic review is to provide an overview of their current capabilities and limitations. METHODS: Medline, Embase and Cochrane databases were searched using free text terms and corresponding controlled vocabulary. Titles and abstracts of retrieved articles were screened for inclusion criteria. Due to the heterogeneity of the retrieved data it was not possible to conduct a meta-analysis. Therefore results are presented in tabulated and narrative format. RESULTS: Out of 2015 articles, 17 pre-clinical and 33 clinical papers met inclusion criteria. Data from 24 articles that reported on accuracy indicates that in recent years navigation accuracy has been in the range of 8-15 mm. Due to discrepancies in evaluation methods it is difficult to compare accuracy metrics between different systems. Surgeon feedback suggests that current state of the art IGS may be useful as a supplementary navigation tool, especially in small liver lesions that are difficult to locate. They are however not able to reliably localise all relevant anatomical structures. Only one article investigated IGS impact on clinical outcomes. CONCLUSIONS: Further improvements in navigation accuracy are needed to enable reliable visualisation of tumour margins with the precision required for oncological resections. To enhance comparability between different IGS it is crucial to find a consensus on the assessment of navigation accuracy as a minimum reporting standard.


Asunto(s)
Hepatectomía/métodos , Laparoscopía/métodos , Neoplasias Hepáticas/cirugía , Cirugía Asistida por Computador/métodos , Humanos , Neoplasias Hepáticas/patología , Pronóstico
8.
Surg Endosc ; 34(10): 4702-4711, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32780240

RESUMEN

BACKGROUND: The laparoscopic approach to liver resection may reduce morbidity and hospital stay. However, uptake has been slow due to concerns about patient safety and oncological radicality. Image guidance systems may improve patient safety by enabling 3D visualisation of critical intra- and extrahepatic structures. Current systems suffer from non-intuitive visualisation and a complicated setup process. A novel image guidance system (SmartLiver), offering augmented reality visualisation and semi-automatic registration has been developed to address these issues. A clinical feasibility study evaluated the performance and usability of SmartLiver with either manual or semi-automatic registration. METHODS: Intraoperative image guidance data were recorded and analysed in patients undergoing laparoscopic liver resection or cancer staging. Stereoscopic surface reconstruction and iterative closest point matching facilitated semi-automatic registration. The primary endpoint was defined as successful registration as determined by the operating surgeon. Secondary endpoints were system usability as assessed by a surgeon questionnaire and comparison of manual vs. semi-automatic registration accuracy. Since SmartLiver is still in development no attempt was made to evaluate its impact on perioperative outcomes. RESULTS: The primary endpoint was achieved in 16 out of 18 patients. Initially semi-automatic registration failed because the IGS could not distinguish the liver surface from surrounding structures. Implementation of a deep learning algorithm enabled the IGS to overcome this issue and facilitate semi-automatic registration. Mean registration accuracy was 10.9 ± 4.2 mm (manual) vs. 13.9 ± 4.4 mm (semi-automatic) (Mean difference - 3 mm; p = 0.158). Surgeon feedback was positive about IGS handling and improved intraoperative orientation but also highlighted the need for a simpler setup process and better integration with laparoscopic ultrasound. CONCLUSION: The technical feasibility of using SmartLiver intraoperatively has been demonstrated. With further improvements semi-automatic registration may enhance user friendliness and workflow of SmartLiver. Manual and semi-automatic registration accuracy were comparable but evaluation on a larger patient cohort is required to confirm these findings.


Asunto(s)
Realidad Aumentada , Hígado/cirugía , Cirugía Asistida por Computador/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
J Prev Med Hyg ; 61(2): E186-E193, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32803004

RESUMEN

BACKGROUND: Good maternal nutrition during pregnancy is important to ensure health for both the mother and the foetus. This study aimed to assess nutritional knowledge and behavior among a group of Egyptian pregnant women in addition to identify the factors influencing both their nutritional knowledge and behavior. METHODS: This comparative cross sectional study included 300 pregnant women attending the antenatal care clinics in 6th of October University private hospital and El-Hussary primary health care (PHC) unit. The data was collected through a modified nutritional survey that was translated from Spanish to Arabic and revised by language experts for clarity. RESULTS: Almost all of the women attending the private hospital were university educated while about half of the women attending the PHC unit were graduated from technical education. In general, the level of knowledge about food requirements of both groups was satisfactory good; however, neither of them fulfilled the WHO recommendations of food intake during pregnancy or the optimum number of meals per day. The mean of random blood glucose was higher among the women attending the PHC unit; the BMI, mid arm circumference and subcutaneous fat were higher among the same group as well. In regard to fulfilling the WHO recommended servings per day, only starch and fat items were fulfilled by both groups, whereas the other three items (vegetables, fruits and dairy products) were merely included in the diets of both groups. CONCLUSIONS: Healthy behavior among pregnant women in both group were influenced by their educational level, occupation as well as their pre-gestational BMI. Those were the only three significant predictive factors, where women with higher education showed an active lifestyle. In addition, women starting with normal BMI before pregnancy had better healthy behaviours including the choice of healthy diets.


Asunto(s)
Dieta/tendencias , Conductas Relacionadas con la Salud , Atención Prenatal , Adulto , Estudios Transversales , Femenino , Predicción , Humanos , Embarazo , Encuestas y Cuestionarios , Adulto Joven
16.
J Viral Hepat ; 21(12): 950-5, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25158783

RESUMEN

The hepatitis C virus (HCV) core protein is able to accumulate genetic p53 mutations and may be considered co-oncogenic. This study investigates 1p36.3 telomere deletion in B-non-Hodgkin's lymphoma (NHL) patients with chronic HCV infection using fluorescence in situ hybridization (FISH) in relation to survival to assess Ki-67 antigen expression. A study group and a control group of 100 patients with B-NHL (50 HCV positive and 50 HCV negative) and 60 control bone marrow biopsies were subjected to FISH for the detection of 1P36.3 deletion and to immunohistochemical staining with Ki-67 antigens. 1p36.3 deletion by FISH was detected in 40% of the study group, and Ki-67 was expressed in approximately 74% of patients. A significant difference was found between positive and negative HCV patients in their overall survival, the qualitative expression of Ki-67 and the quantitative detection of 1p36.3 deletion by FISH. The overall survival was shorter with the presence of an 1p36 deletion by FISH and HCV positive. We concluded that the coexistence of Ki-67 positivity, HCV positivity and 1p36.3 deletion may contribute to infection-related cancers at the 1p36.3 locus.


Asunto(s)
Cromosomas Humanos Par 1 , Hepatitis C Crónica/patología , Antígeno Ki-67/biosíntesis , Linfoma no Hodgkin/patología , Eliminación de Secuencia , Telómero , Adolescente , Adulto , Médula Ósea/patología , Femenino , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/mortalidad , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Adulto Joven
17.
Exp Toxicol Pathol ; 66(9-10): 415-21, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25034310

RESUMEN

A study was designed to evaluate ameliorative effect of propolis against methoxychlor (MXC) induced ovarian toxicity in rat. The organochlorine pesticide (MXC) is a known endocrine disruptor with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether chronic exposure to MXC could cause ovarian dysfunction, two groups of Sprague-Dawley adult female rats were exposed to MXC alone in a dose of 200mg/kg, twice/weekly, orally or MXC dose as previous plus propolis in a dose of 200mg/l/day, in drinking water for 10 months. Another two groups of rat were given corn oil (control) or propolis. Multiple reproductive parameters, ovarian weight, serum hormone levels, ovarian oxidative status and ovarian morphology were examined. In MXC-exposed group, there is a significant decrease in body and ovarian weight vs. control. MXC decreases serum estradiol and progesterone levels. A significant increase in the levels of lipid peroxidation was obtained while a significant decrease of the total antioxidant was recorded. Ovarian histopathology showed primary, secondary and vesicular follicles displaying an atretic morphology. Increase in the ovarian surface epithelium height accompanied with vacuolated, pyknotic oocytes were obtained. The previous toxic effects were neutralized by the administration of propolis in MXC+propolis group. The present results suggest that propolis may be effective in decreasing of MXC-induced ovarian toxicity in rat.


Asunto(s)
Antiinfecciosos/farmacología , Disruptores Endocrinos/toxicidad , Metoxicloro/toxicidad , Ovario/patología , Própolis/farmacología , Animales , Femenino , Insecticidas/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Ovario/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
18.
J Hosp Infect ; 86(1): 53-6, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24239244

RESUMEN

BACKGROUND: Previous studies have suggested that the final outcome of a patient with nosocomial pneumonia (NP) may depend on the patient's illness severity upon admission to the intensive care unit (ICU). AIM: To investigate the relationship between developing NP during hospitalization in an adult ICU and the risk of death with special focus on illness severity at admission in the unit. METHODS: A prospective cohort study was performed among all patients admitted for at least 24h to the ICU of a university reference hospital in Spain from 2006 to 2009. A stratified univariate study was performed according to the patients' illness severity at admission, estimated using the Acute Physiology And Chronic Health Evaluation (APACHE) II index. To determine whether the NP was independently associated with increased mortality in ICU, a multivariate logistic regression analysis was carried out, adjusting for potential confounders. RESULTS: In all, 4427 patients were studied, of whom 233 acquired NP while admitted. Patients who developed NP had a 2.6 higher risk (95% confidence interval: 2.1-3.0) of dying compared with those who did not develop NP. When stratified by the APACHE II index, the significant association remained at each stratum, although the strength of the association decreased as the value of the index increased. In the multivariate analysis, NP was independently associated with death in the ICU. The interaction between NP and the APACHE II index, with a negative coefficient, was also significant. CONCLUSIONS: Developing NP while admitted to the ICU was independently associated with increased mortality. However, the strength of the association decreased as the severity of patient illness upon admission to the ICU increased, not influencing death of patients with severe APACHE II values.


Asunto(s)
Infección Hospitalaria/mortalidad , Infección Hospitalaria/patología , Neumonía/mortalidad , Neumonía/patología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Hospitales Universitarios , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Índice de Severidad de la Enfermedad , España , Análisis de Supervivencia , Resultado del Tratamiento
19.
J Prev Med Hyg ; 55(1): 33-4, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25916031

RESUMEN

Over the last 5 years, a number of outbreaks of measles have occurred in several European Union (EU) countries. Many of these outbreaks continue and/or continued for more than 1 year after the notification of the first case. Curiously in many of measles outbreaks about 10% of the patients were less than 12 months of age. All these patients according to the current EU countries vaccination calendars were not yet vaccinated against measles. Based on the results of measles outbreaks, especially age of affected patients, we should consider changing measles vaccination schedules in all EU countries. Most of mothers between 30 and 40 years of age are not vaccinated against measles, and many of them are not naturally immune against measles. These mothers do not pose antibodies against measles and in turn do not provide vertical protection for their infants. In conclusion, administrating the first dose of measles vaccine in the EU countries should be considered before 12 months of age, most probably at 9 months of age.


Asunto(s)
Brotes de Enfermedades/prevención & control , Esquemas de Inmunización , Vacuna Antisarampión/administración & dosificación , Sarampión/prevención & control , Guías de Práctica Clínica como Asunto/normas , Factores de Edad , Anticuerpos Antivirales/inmunología , Europa (Continente)/epidemiología , Humanos , Lactante , Sarampión/epidemiología , Leche Humana/inmunología
20.
East Mediterr Health J ; 19(1): 4-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23520899

RESUMEN

Evidence- and consensus-based clinical practice guidelines for haemodialysis have recently been developed in Egypt. This study aimed to measure compliance with the guidelines in a sample of 16 government hospitals in Cairo and Giza governorates. Each haemodialysis unit was visited to assess the haemodialysis unit and patient care practices for all patients under dialysis at the time of the visit. The mean percentage compliance with haemodialysis guidelines among all study hospitals was 59.3% (SD 11.2%) overall. Within the 5 separate domains, compliance was: 58.8% (SD 12.4%) for personnel, 68.5% (SD 16.0%) for patient care practices, 61.3% (SD 15.4%) for infection prevention and control, 51.5% (SD 18.2%) for the facility and 56.5% (SD 7.1%) for documentation/ records. There were no statistically significant differences between Cairo and Giza governorates except for facility measures which were slightly better in Giza. Overall, compliance with the developed practice guidelines for haemodialysis in Egypt was not satisfactory and was not uniform across facilities.


Asunto(s)
Adhesión a Directriz/estadística & datos numéricos , Diálisis Renal/normas , Insuficiencia Renal Crónica/terapia , Egipto , Humanos , Guías de Práctica Clínica como Asunto , Diálisis Renal/métodos , Diálisis Renal/estadística & datos numéricos
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