Quad port P-shaped MIMO antenna array for 60 GHz applications.

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.

A Wide-Band Antenna with Circular Polarization Utilizing a U-Shaped Radiator and Parasitic Strip for Wireless Communications.

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.

Lung microbiome of stable and exacerbated COPD patients in Tshwane, South Africa.

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.

Ghrelin ameliorated inflammation and oxidative stress in isoproterenol induced myocardial infarction through the endothelial nitric oxide synthase (eNOS)/nuclear factor erythroid 2-related factor-2 (NRF2)/heme oxygenase-1 (HO-1) signaling pathway.

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.

Performance of image guided navigation in laparoscopic liver surgery - A systematic review.

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.

Comparison of manual and semi-automatic registration in augmented reality image-guided liver surgery: a clinical feasibility study.

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.

Predictive factors for nutritional behavior among pregnant women attending antenatal care clinic in 6th of October City.

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.

Comparison between antral resection in laparoscopic sleeve gastrectomy and classical laparoscopic sleeve gastrectomy

Background: Laparoscopic sleeve gastrectomy (LSG) is essentially a restrictive bariatric operation. Weight loss is achieved by drastically reducing the gastric volume, which in turn leads to reduced food intake. In addition, a series of hormonal changes occurring postoperatively in bariatric patients, contribute to decreased appetite, reduced food intake and long-term weight loss. To date there is a lack of standardization regarding the surgical technique of LSG, which may affect the long-term outcome of the patients. Our study aimed to assess the difference in short and long- term weight loss and complications between antral resection in laparoscopic sleeve gastrectomy and classical laparoscopic sleeve gastrectomy with antral preservation. Patients and Methods: This is a controlled clinical trial held in Ain Shams University Hospital including 40 patients with BMI >30, of them 20 underwent antral resection in laparoscopic sleeve gastrectomy, and the other 20 patients underwent classical laparoscopic sleeve gastrectomy, with antral preservation. Results: Our study showed mild increase in weight loss and BMI reduction after 12 months in the antral resection group compared with the antral preservation group with mean weight loss 70.5kg in antral resection group versus 75.05kg in antral preservation group and mean BMI 27.7% in antral resection group versus 27.9% in antral preservation group, but did not reach statistical significant values. Conclusion: Our study showed that antral resection in laparoscopic sleeve gastrectomy resulted in non-significant better weight loss in the first postoperative year than classical laparoscopic sleeve gastrectomy

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Low level laser therapy for treatment of temporomandibular joint arthritis

Background. Many studies have reported significant pain reduction with low-level laser therapy (LLLT) in acute and chronic mus-culoskeletal pain conditions. Objective. The purpose of this study is to clinically evaluate the effectiveness of LLLT for treatment of temporomandibular joint (TMJ) arthritis. Methodology. This was a clinical trial that included 20 patients with TMJ arthritis. Patients were randomly assigned into two groups of 10 each. Patients of the first group were subjected to LLLT during four weeks, together with standard nonsteroidal anti-inflammatory drugs (NSAIDs) treatment for TMJ arthritis. Patients were evaluated before treatment (T1), after six sessions of laser therapy (T2), after 12 laser applications (T3), and 1 month after the last application (T4). Patients of the second group received only standard NSAIDs treatment for TMJ arthritis. They were evaluated at the same intervals of the first group. At each evaluation, the maximum mouth opening was measured by a millimeter ruler, and patients were asked about the presence or absence TMJ pain. The Visual Analogue Scale (VAS) was used to quantify pain at palpation. Results. All participants were males, and aged between 41 and 70 years old. In LLLT and NSAIDs group follow up of maximum mouth opening in mm showed a significant improvement. The same significant improvement was noted in NSAIDs group. Comparison between LLLT and NSAIDs group and NSAIDs group showed a significant improvement in favor of the LLLT and NSAIDs group during the 3 follow up periods. Same improvement in favor for LLLT and NSAIDs group was noted in the VAS. Conclusion. LLLT in patients with TMJ arthritis is a safe and effective technique

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La ciencia de la revisión en la investigación médica / The sciencie of review in medical research

En los últimos años el metaanálisis ha suscitado mucho interés en la investigación médica; sin embargo, numerosas áreas metodológicas, en concreto las referentes a los sesgos, y al objetivo del metaanálisis continúan siendo controvertidas. El presente trabajo revisa los diferentes métodos usados en la revisión. Finalmente, resumimos los pasos para realizar una revisión narrativa o sistemática

Much attention has been given in recent years to meta-analysis in medical research; however, numerous methodologic issues particularly with respect to biases and the use of meta-analysis are still controversial. The current study summarizes the different methods used in narrative and systematic reviews. Finally, we explain the main steps for conducting a meta-analysis

Telomeric 1p36.3 deletion and Ki-67 expression in B-Non-Hodgkin's Lymphoma patients associated with chronic hepatitis C virus infection.

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.

The ameliorative effect of propolis against methoxychlor induced ovarian toxicity in rat.

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.