Reduced parenchymal cerebral blood flow is associated with greater progression of brain atrophy: The SMART-MR study

Global cerebral hypoperfusion may be involved in the aetiology of brain atrophy; however, long-term longitudinal studies on this relationship are lacking. We examined whether reduced cerebral blood flow was associated with greater progression of brain atrophy. Data of 1165 patients (61 ± 10 years) from the SMART-MR study, a prospective cohort study of patients with arterial disease, were used of whom 689 participated after 4 years and 297 again after 12 years. Attrition was substantial. Total brain volume and total cerebral blood flow were obtained from magnetic resonance imaging scans and expressed as brain parenchymal fraction (BPF) and parenchymal cerebral blood flow (pCBF). Mean decrease in BPF per year was 0.22% total intracranial volume (95% CI: –0.23 to –0.21). Mean decrease in pCBF per year was 0.24 ml/min per 100 ml brain volume (95% CI: –0.29 to –0.20). Using linear mixed models, lower pCBF at baseline was associated with a greater decrease in BPF over time (p = 0.01). Lower baseline BPF, however, was not associated with a greater decrease in pCBF (p = 0.43). These findings indicate that reduced cerebral blood flow is associated with greater progression of brain atrophy and provide further support for a role of cerebral blood flow in the process of neurodegeneration.     

The clinical effectiveness of reconstructing 18F-sodium fluoride PET/CT bone using Bayesian penalized likelihood algorithm for evaluation of metastatic bone disease in obese patients

Objective:A new Bayesian penalized likelihood reconstruction algorithm for positron emission tomography (PET) (Q.Clear) is now in clinical use for fludeoxyglucose (FDG) PET/CT. However, experience with non-FDG tracers and in special patient populations is limited. This pilot study aims to compare Q.Clear to standard PET reconstructions for ¹⁸F sodium fluoride (¹⁸F-NaF) PET in obese patients.Methods:30 whole body ¹⁸F-NaF PET/CT scans (10 patients with BMI 30–40 Kg/m² and 20 patients with BMI >40 Kg/m²) and a NEMA image quality phantom scans were analyzed using ordered subset expectation maximization (OSEM) and Q.Clear reconstructions methods with B400, 600, 800 and 1000. The images were assessed for overall image quality (IQ), noise level, background soft tissue, and lesion detectability, contrast recovery (CR), background variability (BV) and contrast-to-noise ratio (CNR) for both algorithms.Results:CNR for clinical cases was higher for Q.Clear than OSEM (p < 0.05). Mean CNR for OSEM was (21.62 ± 8.9), and for Q.Clear B400 (31.82 ± 14.6), B600 (35.54 ± 14.9), B800 (39.81 ± 16.1), and B1000 (40.9 ± 17.8). As the β value increased the CNR increased in all clinical cases. B600 was the preferred β value for reconstruction in obese patients. The phantom study showed Q.Clear reconstructions gave lower CR and lower BV than OSEM. The CNR for all spheres was significantly higher for Q.Clear (independent of β) than OSEM (p < 0.05), suggesting superiority of Q.Clear.Conclusion:This pilot clinical study shows that Q.Clear reconstruction algorithm improves overall IQ of ¹⁸F-NaF PET in obese patients. Our clinical and phantom measurement results demonstrate improved CNR and reduced BV when using Q.Clear. A β value of 600 is preferred for reconstructing ¹⁸F-NaF PET/CT with Q.Clear in obese patients.Advances in knowledge:¹⁸F-NaF PET/CT is less susceptible to artifacts induced by body habitus. Bayesian penalized likelihood reconstruction with¹⁸F-NaF PET improves overall IQ in obese patients.     

Abdominal Dermis-Fat Graft Versus Conventional Temporalis Myofascial Flap Interposition in Temporomandibular Joint Ankylosis: A Prospective Clinical Comparative Study

IntroductionTemporomandibular joint (TMJ) ankylosis is an extremely disabling condition with almost complete inability to open the jaws causing difficulty in chewing, speech, poor oral hygiene and cosmetic disfigurement. Temporalis myofascial flap still remains the most common interpositional material used; however, patients usually complain of pain during movement, unesthetic bulging in the temporal region and trismus due to scar contracture. The main aim of the study was to evaluate the efficacy of abdominal dermis-fat graft and compare it with temporalis myofascial flap as to see which of the two grafts offers more advantages and provides better postoperative results following TMJ ankylosis surgery. Materials and MethodsA total of 30 diagnosed cases of TMJ ankylosis were randomly divided into two groups of 15 patients each. All the patients underwent TMJ ankylosis release under general anesthesia followed by abdominal dermis-fat interposition in Group A and temporalis muscle in Group B. The patients were assessed for pre-operative and postoperative mouth opening (immediate and 6 month postoperative), pain during physiotherapy, donor and surgical site complications and recurrence of ankylosis.ResultsThe mean maximum inter-incisal opening in dermis-fat group was significantly higher than temporalis group both at immediate and 6 month postoperative periods (p = 0.041, 0.001). Physiotherapy was less painful in dermis-fat group than in temporalis group, and the differences in VAS scores among the 2 groups showed high statistical significance (p < 0.001). Hypertrophic scar developed at the donor site in 2 patients in dermis-fat group; however, it was located below the beltline and hardly noticeable. A total of 9 patients (4 in Group A and 5 in Group B) developed temporary facial nerve weakness, and no case of re-ankylosis was noted in either group.ConclusionDermis-fat graft in temporomandibular joint ankylosis showed better results than conventional temporalis myofascial flap in terms of postoperative mouth opening, physiotherapy and jaw function with esthetically acceptable results.     

Fundamentals and recent progress relating to the fabrication,functionalization and characterization of mesostructured materials using diverse synthetic methodologies

Since 1990 and the invention of the very first generation of ordered mesoporous silica materials, several innovative methodologies have been applied to synthesize, characterize, and modify silica/non-silica mesoporous materials. The growth of the mesoporous materials field has generated significant environmental and economic advantages compared to various other industrial developments. According to the literature, there are several key synthesis approaches and parameters that can affect the structural, textural and morphological characteristics of mesoporous materials. To date, huge attempts have been made to maximize the activities and selectivities of these materials through either the in situ or post-synthesis functionalization of the large interior surface areas and internal mesostructured frameworks in the presence of specific organic/inorganic components. However, the main challenge is to provide good control over the incorporation and distribution of multiple guest components within the mesostructured hosts. Mesostructured materials have received great attention for various applications, such as being used in electronics, medicine, photocatalysis, catalyst supports, catalysis, absorbers, sensors, gas separation, etc. In the current paper, several recent developments have been highlighted and reviewed regarding the fabrication and characterization of siliceous/non-siliceous mesoporous materials via various synthetic approaches. Furthermore, the availability of diverse functionalization methods has been reviewed to provide comprehensive approaches for synthesizing new generations of suitably modified mesoporous materials with superior structural, physicochemical, and textural characteristics.

Since 1990 and the invention of the very first generation of ordered mesoporous silica materials, several innovative methodologies have been applied to synthesize, characterize, and modify silica/non-silica mesoporous materials.     

The renin-angiotensin-aldosterone system and hypertension in primary hyperparathyroidism

To evaluate the role of the renin-angiotensin-aldosterone system in the hypertension associated with primary hyperparathyroidism, we measured plasma renin activity and aldosterone concentration before and after maneuvers to suppress and stimulate this system in 11 hypertensive patients with primary hyperparathyroidism. We also measured plasma or urinary norepinephrine concentration to examine the role of catecholamines in the hypertension. The results were compared with an age- and race-matched control population. While the mean plasma aldosterone concentrations were normal, the mean plasma renin activity in response to furosemide stimulation was subnormal in subjects with hyperparathyroidism. Plasma or urinary norepinephrine concentrations were within the normal range. Thus a specific abnormality of the renin-angiotensin-aldosterone system or catecholamines could not be identified in these hypertensives with primary hyperparathyroidism.     

Impact of Ciprofloxacin and Clindamycin Administration on Gram-Negative Bacteria Isolated from Healthy Volunteers and Characterization of the Resistance Genes They Harbor

The aim of this study was to assess the impact of ciprofloxacin, clindamycin, and placebo administration on culturable Gram-negative isolates and the antibiotic resistance genes they harbor. Saliva and fecal samples were collected from healthy human volunteers before and at intervals, up to 1 year after antibiotic administration. Samples were plated on selective and nonselective media to monitor changes in different colony types or bacterial species. Following ciprofloxacin administration, there was a decrease of Escherichia coli in feces and after clindamycin administration a decrease of Bacteroides in feces and Leptotrichia in saliva, which all returned to pretreatment levels within 1 to 4 months. Ciprofloxacin administration also resulted in an increase in ciprofloxacin-resistant Veillonella in saliva, which persisted for 12 months. Additionally, 949 aerobic and anaerobic isolates purified from ciprofloxacin- and clindamycin-containing plates were screened for the presence of resistance genes. Resistance gene carriage was widespread in isolates from all three treatment groups, and no association was observed between genes and antibiotic administration. Although the anaerobic component of the microbiota was not a major reservoir of aerobe-associated antimicrobial resistance (AMR) genes, we detected the sulfonamide resistance gene sul2 in anaerobic isolates. The longitudinal nature of the study allowed identification of distinct Escherichia coli clones harboring multiple resistance genes, including one carrying an extended-spectrum β-lactamase bla_CTX-M group 9 gene, which persisted in the gut for up to 4 months. This study provided insight into the effects of antibiotic administration on healthy microbiota and the diversity of resistance genes harbored therein.     

Assessment of knowledge of celiac disease among health care professionals

Objectives:

To assess knowledge of celiac disease among medical professionals (physicians).

Methods:

We conducted a cross-sectional survey of hospital-based medical staff in primary, secondary, and tertiary care public, and private hospitals in Riyadh, Saudi Arabia (KSA). We carried out the study between January 2013 and January 2104 at King Khalid University Hospital, King Saud University, Riyadh, KSA. A pretested questionnaire was distributed to the potential participants. A scoring system was used to classify the level of knowledge of participants into 3 categories: poor, fair, and good.

Results:

A total of 109 physicians completed the survey and of these participants, 86.3% were from public hospitals, and 13.7% from private hospitals; 58.7% were males. Of the physicians, 19.2% had poor knowledge. Interns and residents had fair to good knowledge, but registrars, specialists, and even the consultants were less knowledgeable of celiac disease.

Conclusion:

Knowledge of celiac disease is poor among a significant number of physicians including consultants, which can potentially lead to delays in diagnosis. Educational programs need to be developed to improve awareness of celiac disease in the health care profession.Celiac disease (CD) is an autoimmune disorder that is triggered by ingestion of gluten in genetically susceptible individuals. This leads to small intestinal villous atrophy and its ensuing complications. Celiac disease is a common disorder, and the prevalence seems to be on the rise. The exact prevalence of CD in the Middle East and Saudi Arabia (KSA) is not known, but it affects approximately 0.5-1% of the general population in the West.1 The classical presentation of CD is in early childhood with a mal-absorptive picture leading to diarrhea and failure to thrive. However, many cases now present in adulthood. It can also have a variety of non-intestinal presentations such as anemia, fatigue, bone disease, liver enzyme elevation, and infertility.1,2 Highly sensitive screening tests such as immunoglobulin (Ig)A-tissue transglutaminase antibody are now available to screen for CD. The diagnosis of CD is confirmed with small intestinal biopsies, and treatment consists of a strict gluten-free diet for life.3 Health care professionals need to be aware of both the classical and non-classical (extra-intestinal) manifestations of CD in order to make a timely diagnosis. Delays in diagnosis can lead to potentially serious complications such as osteoporosis and small intestinal lymphoma.4 The purpose of the study was to assess the knowledge of CD among the medical professionals. The information obtained will help to design and conduct educational and training programs on CD.     

Antipyretic,anti-inflammatory and analgesic activity of <Emphasis Type="Italic">Acacia hydaspica</Emphasis> R. Parker and its phytochemical analysis

Background

Inflammation and pain underlies several pathological conditions. Synthetic drugs used for the management of these conditions carry severe toxic effects. Globally efforts are ongoing to introduce novel medicinal plants to develop effective, economic and innocuous drugs. The current study was aimed at investigating the antipyretic, anti-inflammatory and analgesic activity of methanol extract of A. hydaspica aerial parts (AHM) and its active fraction. Furthermore identification and isolation of polyphenolic compounds was carried out to identify the active principles.

Methods

Yeast induced pyrexia, Paw edema, acetic acid-induced writhing and hot plate test were carried out in vivo. HPLC-DAD analysis and combination of different chromatographic techniques, involving vacuum liquid chromatography (VLC) and flash chromatography (FC) were carried out for chemical characterization. The structural heterogeneity of flavanols was characterized by ESI- MS, ¹H NMR, ¹³C NMR and ²D NMR spectroscopic analyses, and also by comparison with reported literature.

Results

Oral administration of A. hydaspica methanol extract (AHM) and A. hydaspica ethyl acetate fraction (AHE), showed dose and time dependent decrease in body temperature in yeast induced pyrexia, comparable to standard, Paracetamol. AHM and AHE (150 mg/kg) significantly (p?<?0.001) inhibit pain sensation in various pain models, i.e. acetic acid induced writhing and hot plate test. Similarly AHM and AHE demonstrated an anti-inflammatory effect in carrageenan-induced paw edema in rats and 150 mg/kg dose being distinctly more effective (91.92% inhibition). When studied on prostaglandin E₂ (PGE₂) induced edema in rats, AHM and AHE showed maximum inhibition of edema at 150 mg/kg after 4 h. HPLC chromatogram of AHM revealed the presence of gallic acid, catechin, rutin and caffeic acid. Chromatographic separation and structure characterization of AHE, has led to the identification of three flavan-3-ol derivative including 7-O-galloyl catechin, +catechin and methyl gallate, which have been reported for the first time in A. hydaspica.

Conclusion

These results revealed that the presence of bioactive compounds in A. hydaspica might be responsible for the pharmacological activities, confirming the indigenous utility of A. hydaspica against inflammatory disorders.