A comprehensive study of Al-Cu-Mg system reinforced with nano-ZrO2 particles synthesized by powder metallurgy technique

More focus has recently been placed on enhancing the strength, elastic modulus, coefficient of thermal expansion (CTE), wear and corrosion resistance, and other qualities of aluminum (Al) alloys by varying the quantity of ceramics added for a range of industrial uses. In this regard, Al-4.2-Cu-1.6Mg matrix nanocomposites reinforced with nano-ZrO2 particles have been created using the powder metallurgy approach. The microstructure and particle size distributions of the produced powders were analyzed using a diffraction particle size analyzer, XRD, TEM, and SEM. To achieve good sinterability, the powders were compacted and sintered in argon. The sintered nanocomposites' mechanical, elastic, and physicochemical characteristics were measured. Additionally, the behavior of corrosion, wear, and thermal expansion were examined. The results showed a decrease in the particle sizes of the Al-Cu-Mg alloy by adding ZrO2 nanoparticles up to 45.8 nm for the composite containing 16 wt.% ZrO2. By increasing the sintering temperature to 570 °C, the densification of nanocomposites was enhanced. Also, the coefficient of thermal expansion and wear rate remarkably decreased by about 28 and 37.5% by adding 16 wt.% ZrO2. Moreover, microhardness yield, strength, and Young's modulus were enhanced to 161, 145, and 64%, respectively, after adding 16 wt.% ZrO2. In addition, increasing the exposure time was responsible for decreasing the corrosion rate for the same sample.

Updated clinical practice treat-to-target guidelines for JIA management: the Egyptian College of Pediatric Rheumatology initiative

Background

These updated guidelines aimed to provide appropriate and convenient guidelines for the treatment of various types of juvenile idiopathic arthritis (JIA).

Using the Delphi technique, this study was conducted to reach expert consensus on a treat-to-target management strategy for JIA. According to the PICO (patient/population, intervention, comparison, and outcomes) approach, the preliminary scientific committee identified a total of 17 key clinical questions. To assemble evidence on the advantages and dangers associated with JIA treatments, an evidence-based, systematic literature review was conducted. Researchers and clinicians with experience in JIA management were identified by the core leadership team. To establish a consensus on the management suggestions for JIA patients, a Delphi approach (2 rounds) was used.

Results

An online survey was applied to the expert panel (n = 27), and 26 of them completed both rounds. At the conclusion of round 2, a total of eighteen (18) recommendation items were gathered, which were divided into four sections to address the four key JIA categories. The percentage of those who agreed with the recommendations (ranks 7–9) ranged from 83.2 to 100% (average 86.8%). The phrasing of all 18 clinical standards identified by the scientific committee was agreed upon (i.e. 75% of respondents strongly agreed or agreed). Algorithms have been proposed for the management of JIA polyarthritis, oligoarthritis, and systemic JIA.

Conclusion

A wide and representative panel of experts initiated a consensus about the management of JIA. The created guidelines give a complete approach to the management of JIA for all healthcare professionals involved in its management, as well as a means of monitoring and evaluating these guidelines on a regular basis.

P063 Consensus-based recommendations for treat to target management of immunoglobulin A vasculitis

Background

IgAvasculitis (IgAV) is the commonest cause of vasculitis in childhood.

It is characterized by small vessel vasculitis of the skin, gastrointestinal tract, kidneys, joints, and, rarely, the lungs and the central nervous system. There is paucity of international guidelines for management of IgA V. the Objective is to develop guidelines specific for Egyptian children with IgA vasculitis.

Method

This study was carried out to achieve an Egyptian expert consensus on a treat-to-target management strategy for IgA vasculitis using Delphi technique. The preliminary scientific committee identified a total of 16 key clinical questions according to the Patient/Population, Intervention, Comparison, and Outcomes (PICO) approach. Delphi process was implemented (2-rounds) to reach a consensus.

Results

An online questionnaire were sent to expert panel (n = 26) who participated in the two rounds. At the end of round 2, a total of 20 recommendation items, categorized into 2 sections were obtained. Agreement with the recommendations (rank 7–9) ranged from 91.7–100%. Consensus was reached (i.e. ≥75% of respondents strongly agreed or agreed) on the wording of all the 20 clinical standards identified by the scientific committee. Algorithms for the management have been suggested.

Conclusion

This was an expert, consensus recommendations for the diagnosis and treatment of IgA V and IgA V nephritis, based on best available evidence and expert opinion.

P050 Consensus based practice guidelines for the management and treatment of Juvenile familial Mediterranean fever: the Egyptian College of Paediatric Rheumatology initiative

Background

Familial Mediterranean fever (FMF) is the most common monogenic auto-inflammatory disease, with the highest prevalence amongst Mediterranean countries including Egypt (where there is high carrier rate of MEFV gene), characterized by recurrent attacks of fever and polyserositis. Mutations in the MEFV gene encoding pyrin has been associated with the disease, which causes exaggeration of the inflammatory response through uncontrolled interleukin production. Issuing updated treatment recommendations are vital for the treating healthcare professionals to get well acquainted with its diagnosis & treatment. To produce consensus-based recommendations to guide the early diagnosis, management and follow-up of patients with FMF.

Methods

The Patient/Population, Intervention, Comparison, and Outcomes (PICO) questions were developed and refined by the core team.

A qualitative synthesis of scientific evidence based on systematic review and clinical experience was conducted to compile evidence for the diagnosis and management of FMF.

A consensus process was conducted among the expert panel to generate the final recommendations and grade their strength.

3 rounds of Delphi process were carried out.

Results

Following 3 Delphi rounds, recommendations were developed for: early diagnosis, who to treat, treatment targets, genetic testing and its interpretation in association with clinical presentation, treatment of FMF and dealing with acute attacks, monitoring of management, identify treatment response, systemic affection, persistent attacks or inflammation, resistant cases, protracted symptoms, as well as remission status.

Algorithm for patients’ diagnosis and management is provided.

The final document comprises 12 recommendations, each presented with its degree of agreement (0–10), Level of agreement, grade of recommendation and rationale. The degree of agreement was >7/10 in all instances.

Conclusion

This guideline provides comprehensive approach to the accurate diagnosis and effective management/monitoring of FMF. It also represents a model for the incorporation of medical genetics practice into the more traditional domains of general medicine.

Therapeutic efficacy of seaweed extract (Ulva Fasciata Delile) against invasive candidiasis in mice

Candida is the most frequent common causes of invasive fungal infections and associated with high morbidity and mortality. Most of available antifungal agents have side effects. This opened up new avenues to investigate the antifungal efficacy of active extracts from marine algae. So the aim of this study was to evaluate the protective and the curative effect of Ulva fasciata extract against an invasive candidiasis in mice and to study its underlying mechanism. The active ingredients of Ulva fasciata extract were evaluated using HPLC and GC/MS. Fifty mice were included in current work, and the level of inflammatory markers; Interleukin (IL)-4, IL-12, Interferon-gamma (IFN-γ) and Tumor necrosis factor-alpha (TNF-α) were determined using ELISA kits. Hematological, biochemical and oxidative stress parameters were determined using commercial kits. Moreover, the histopathological examinations were carried on liver, kidney and spleen for all groups. The results obtained showed that treatment with U. fasciata either before or after Candida infection significantly improved the hematological, biochemical alterations and antioxidant status caused by this infection. Furthermore, the U. fasciata reduced histopathological changes induced by Candida as well as it could increase the expression of IL-12 and IFN-γ while minimized the expression of TNF-α and IL-4 in all infected mice compared to infected untreated mice. These data propose that U. fasciata can ameliorate inflammatory reactions related to Candida albicans cytotoxicity via its ability to augment cellular antioxidant defenses by its active compounds.

Prostate tissue texture feature extraction for suspicious regions identification on TRUS images

In this work, two different approaches are proposed for region of interest (ROI) segmentation using transrectal ultrasound (TRUS) images. The two methods aim to extract informative features that are able to characterize suspicious regions in the TRUS images. Both proposed methods are based on multi-resolution analysis that is characterized by its high localization in both the frequency and the spatial domains. Being highly localized in both domains, the proposed methods are expected to accurately identify the suspicious ROIs. On one hand, the first method depends on a Gabor filter that captures the high frequency changes in the image regions. On the other hand, the second method depends on classifying the wavelet coefficients of the image. It is shown in this paper that both methods reveal details in the ROIs which correlate with their pathological representations. It was found that there is a good match between the regions identified using the two methods, a result that supports the ability of each of the proposed methods to mimic the radiologist's decision in identifying suspicious regions. Studying two ROI segmentation methods is important since the only available dataset is the radiologist's suspicious regions, and there is a need to support the results obtained by either one of the proposed methods. This work is mainly a preliminary proof of concept study that will ultimately be expanded to a larger scale study whose aim will be introducing an assisting tool to help the radiologist identify the suspicious regions.

Prostate cancer spectral multifeature analysis using TRUS images

This paper focuses on extracting and analyzing different spectral features from transrectal ultrasound (TRUS) images for prostate cancer recognition. First, the information about the images' frequency domain features and spatial domain features are combined using a Gabor filter and then integrated with the expert radiologist's information to identify the highly suspicious regions of interest (ROIs). The next stage of the proposed algorithm is to scan each identified region in order to generate the corresponding 1-D signal that represents each region. For each ROI, possible spectral feature sets are constructed using different new geometrical features extracted from the power spectrum density (PSD) of each region's signal. Next, a classifier-based algorithm for feature selection using particle swarm optimization (PSO) is adopted and used to select the optimal feature subset from the constructed feature sets. A new spectral feature set for the TRUS images using estimation of signal parameters via rotational invariance technique (ESPRIT) is also constructed, and its ability to represent tissue texture is compared to the PSD-based spectral feature sets using the support vector machines (SVMs) classifier. The accuracy obtained ranges from 72.2% to 94.4%, with the best accuracy achieved by the ESPRIT feature set.

Bronchoscopic study on aetiology of chronic cough in HIV-infected adults with negative sputum smears for Mycobacterium tuberculosis at Kenyatta National Hospital, Nairobi

OBJECTIVE

To establish the aetiology of chronic cough in HIV-infected patients with negative sputum smears for Acid Fast Bacilli (AFB).

DESIGN

A cross-sectional descriptive study.

SETTING

Kenyatta National Hospital, a tertiary referral centre in Kenya

SUBJECTS

Sixty five HIV-infected adults presenting with chronic cough and negative sputum smears for AFBs.

RESULTS

Sixty-two patients were included in the final analysis. Aetiology of chronic cough was established in 42 (68%) patients. Pneumocystis jiroveci, bacterial pneumonia and Mycobacterium tuberculosis were diagnosed in 22 (35.5%), 17 (27.4%) and 14 (22.5%) patients respectively. Majority (98%) of patients with a diagnosis had multiple causes established in them. Ciprofloxacin had activity against 91% of the isolated organisms while Penicillin was active against 35% only.

CONCLUSION

This study documents Pneumocystis jiroveci pneumonia as a common cause of morbidity in a subset of HIV infected patients with chronic cough and negative sputum smears for AFB in Kenya.

Prostate cancer multi-feature analysis using trans-rectal ultrasound images

This note focuses on extracting and analysing prostate texture features from trans-rectal ultrasound (TRUS) images for tissue characterization. One of the principal contributions of this investigation is the use of the information of the images' frequency domain features and spatial domain features to attain a more accurate diagnosis. Each image is divided into regions of interest (ROIs) by the Gabor multi-resolution analysis, a crucial stage, in which segmentation is achieved according to the frequency response of the image pixels. The pixels with a similar response to the same filter are grouped to form one ROI. Next, from each ROI two different statistical feature sets are constructed; the first set includes four grey level dependence matrix (GLDM) features and the second set consists of five grey level difference vector (GLDV) features. These constructed feature sets are then ranked by the mutual information feature selection (MIFS) algorithm. Here, the features that provide the maximum mutual information of each feature and class (cancerous and non-cancerous) and the minimum mutual information of the selected features are chosen, yielding a reduced feature subset. The two constructed feature sets, GLDM and GLDV, as well as the reduced feature subset, are examined in terms of three different classifiers: the condensed k-nearest neighbour (CNN), the decision tree (DT) and the support vector machine (SVM). The accuracy classification results range from 87.5% to 93.75%, where the performance of the SVM and that of the DT are significantly better than the performance of the CNN.

Simultaneous determination of artemether and its major metabolite dihydroartemisinin in plasma by gas chromatography-mass spectrometry-selected ion monitoring

A sensitive, selective, and reproducible GC-MS-SIM method was developed for determination of artemether (ARM) and dihydroartemisinin (DHA) in plasma using artemisinin (ART) as internal standard. Solid phase extraction was performed using C18 Bond Elut cartridges. The analysis was carried out using a HP-5MS 5% phenylmethylsiloxane capillary column. The recoveries of ARM, DHA and ART were 94.9 +/- 1.6%, 92.2 +/- 4.1% and 81.3 +/- 1.2%, respectively. The limit of quantification in plasma was 5 ng/ml (C.V. < or = 17.4% for ARM and 15.2% for DHA). Calibration curves were linear with R2 > or = 0.988. Within day coefficients of variation were 3-10.4% for ARM and 7.7-14.5% for DHA. Between day coefficients of variations were 6.5-15.4% and 7.6-14.1% for ARM and DHA. The method is currently being used for pharmacokinetic studies. Preliminary data on pharmacokinetics showed Cmax of 245.2 and 35.6 ng/ml reached at 2 and 3 h and AUC0-8 h of 2463.6 and 111.8 ngh/ml for ARM and DHA, respectively.

Reconstruction of resected mandibles using a hydroxyapatite veterinary bone graft

A newly developed bone equivalent hydroxyapatite was derived from veterinary bone (VHAP). Sections of 1 cm of six rabbit mandibles were equally replaced by this VHAP graft. Radiological studies by X-ray were performed pre-operatively, immediately, and 1, 2 and 3 months post-operatively. The graft host-bone interface was examined periodically by scanning electron microscopy (SEM). Accompanying structural changes of the graft 3 months post-operatively were compared with the pre-operative findings by infra-red (IR) spectroscopic analysis. Complete union of the biomaterial to the host bone after 3 months was evidenced radiologically. SEM proved complete graft integration. This was accompanied by a decrease in optical density of the IR analysis of post-operative VHAP, indicating some leaching of the ions. Clinically, the graft was completely incorporated in the mandible without any complications. We discuss the use of VHAP in humans to reconstruct post-surgical mandibular defects.

A histological study of the innervation of developing mouse teeth

The innervation of developing mouse teeth between initial formation and crown formation was investigated using silver-stained serial sections. The developing innervation correlated with the stage of development of individual teeth rather than the chronological age of the mice. Nerves approached the developing dental papilla during the bud stage and formed a basal plexus below the dental papilla in the early cap stage. Nerve fibres from this plexus spread into the dental follicle as it began to develop. However, nerves did not enter the dental papilla until crown formation commenced, when the innervation was fairly rapid. Innervation commenced in the incisor teeth as soon as dentinogenesis started but not until a thin layer of enamel had been formed in the molar teeth. Although some of the early fibres were associated with blood vessels, many nerves lay free in the pulp. The absence of nerves in intimate relationship to the presumptive dental regions during the inductive phase of tooth development suggests that neural induction plays no part in the initiation of odontogenesis. However, it is not possible, from a purely histological study such as this, to attribute any function to the nerves at other stages of tooth development until the neurotransmitter content, and hence the type and likely function of the nerves, is established.

A histochemical study of the cholinergic and adrenergic innervation of the developing teeth and oral tissues in the mouse

The dental follicle and papilla are innervated at different stages of tooth development. The type of nerves innervating these structures at different stages was investigated using an enzymic method for acetylcholinesterase (AChE) and direct visualization for noradrenaline on fetal and neonatal stages up to 7 days after birth. Glandular and muscular tissue were positive for AChE in 17-day fetuses but no reaction was observed in the teeth or supporting tissues up to 7 days after birth. Noradrenaline was detected in blood vessels at 18 days and in glandular tissue at birth but was not observed in the teeth within the period covered. It is unlikely that AChE plays any role in the innervation of teeth; the adrenergic nerve supply probably develops later.

The ontogeny of substance P fibers in the mouse trigeminal nerve

The putative neurotransmitter substance P was localized in the embryonic and neonatal mouse trigeminal nerve by indirect immunofluorescence. Central terminals in the nucleus caudalis gave a positive substance P-like immunofluorescence (SPLI) reaction of E13-E14. SPLI subsequently appeared in the peripheral mucous and cutaneous nerves at E16-17 at which time trigeminal nucleus cell bodies were also positive. These findings indicate the early development of primary afferent nociceptive pathways.

The ontogeny of substance P--containing nerve fibres in the developing mouse dentition

The putative neurotransmitter, substance P, was localised in the developing teeth and periodontium of mice by indirect immunofluorescence. Substance P-containing fibres were visible in the incisor dental follicle eighteen days post-conception and entered the pulp two days after birth. The first molar pulp was innervated four days after birth and the second molar six days after birth. Innervation of the teeth by substance P fibres was delayed compared with the mucous and cutaneous innervation of adjacent areas and correlated with the stage of development of the teeth rather than the chronological age of the animal. The innervation of developing dental structures by substance P probably represents the establishment of a sensory supply prior to function of the tooth.