Imaging the master regulator of the antioxidant response in non-small cell lung cancer with positron emission tomography

Mutations in the NRF2-KEAP1 pathway are common in non-small cell lung cancer (NSCLC) and confer broad-spectrum therapeutic resistance, leading to poor outcomes. The cystine/glutamate antiporter, system xc-, is one of the >200 cytoprotective proteins controlled by NRF2, which can be non-invasively imaged by (S)-4-(3-18F-fluoropropyl)-l-glutamate ([18F]FSPG) positron emission tomography (PET). Through genetic and pharmacologic manipulation, we show that [18F]FSPG provides a sensitive and specific marker of NRF2 activation in advanced preclinical models of NSCLC. We validate imaging readouts with metabolomic measurements of system xc- activity and their coupling to intracellular glutathione concentration. A redox gene signature was measured in patients from the TRACERx 421 cohort, suggesting an opportunity for patient stratification prior to imaging. Furthermore, we reveal that system xc- is a metabolic vulnerability that can be therapeutically targeted for sustained tumour growth suppression in aggressive NSCLC. Our results establish [18F]FSPG as predictive marker of therapy resistance in NSCLC and provide the basis for the clinical evaluation of both imaging and therapeutic agents that target this important antioxidant pathway.

Mucocutaneous Changes in End-Stage Renal Disease Under Regular Hemodialysis - A Cross-Sectional Study

Introduction

Patients with end-stage renal disease (ESRD) suffer from mucocutaneous changes that could significantly impair the quality of life. We aimed this study to assess the mucocutaneous changes in hemodialysis patients and to correlate the serum creatinine to these changes.

Methods

Data were collected from the Hemodialysis Center at Benha University. A cross-sectional study design on 130 chronic kidney disease (CKD) patients (30-60 years old, 84 males, 46 females) undergoing hemodialysis. Oral examinations were done for these patients as per the modified World Health Organization oral health survey 2013 criteria. All the mucocutaneous changes were recorded then types, distribution, and frequencies were calculated and correlated to serum creatinine.

Results

Mucocutaneous abnormalities were present in 100% of the studied CKD sample. We observed that pallor (76.2%), xerostomia (70%), petechiae/purpura (49.2%), altered taste (49.2%), and lip pigmentation (40.8%) were the most prevalent mucocutaneous changes among the CKD patients undergoing hemodialysis. A strong association was detected between serum creatinine and the following: abnormal lip pigmentation and lichen planus.

Discussion

There is an association between lip pigmentation and lichen planus in CKD patients and the level of serum creatinine as the higher level of serum creatinine was found in the patients with abnormal lip pigmentation and the atrophic lichen planus patients.

The frequency of periodontitis in end-stage renal disease on hemodialysis in a sample of Egyptian population: multi-center clinical cross-sectional study

BACKGROUND

There is a general assumption that periodontal disease is highly prevalent among patients with chronic renal failure undergoing hemodialysis. The aim of the study to estimate the frequency of periodontitis in patients on hemodialysis among a sample of the Egyptian population, as well as the correlation between different clinical parameters of periodontal status with serum creatinine and blood urea. This may rule out the bidirectional relationship between periodontitis and renal failure in patients on hemodialysis.

METHODS

The study was conducted on 263 hemodialysis patients (165 males and 98 females) at three dialysis centers in Benha Governorate, Egypt (Benha Hospital, Tukh hospital, Qalyub hospital). Periodontal parameters including plaque index (PI), gingival index (GI), clinical attachment level (CAL), and probing pocket depth (PPD) had been recorded in these patients. Serum urea and creatinine levels had been measured, the data had been collected and undergone statistical analysis.

RESULTS

Frequency of periodontitis was 85.6% with stage III is the most prevalent stage. There was a significant positive strong correlation between age and periodontitis stage (rs = 0.707, p < 0.001). There was a positive correlation between clinical parameters and serum creatinine level.

CONCLUSION

In the present study, a high frequency of periodontitis had been found among ESRD patients on hemodialysis in the severe form (stage III) periodontitis. There was a significant direct correlation between the severity of periodontitis and CAL with a duration of hemodialysis. There was a weak insignificant association between periodontal indices (PD, BOP, and plaque score) and duration of hemodialysis.

Radiotracer stereochemistry affects substrate affinity and kinetics for improved imaging of system xC - in tumors

Amino acid utilization is perturbed in cancer cells, which rewire their metabolism to support cell survival and proliferation. This metabolic reprogramming can be exploited for diagnostic purposes through positron emission tomography imaging of fluorine-18 labeled amino acids. Despite its promise, little is known regarding transporter-recognition of non-natural amino acid stereoisomers or their utility for cancer imaging. We report here the synthesis and in vivo characterization of a radiolabeled amino acid (R)-4-(3-¹⁸F-fluoropropyl)-ʟ-glutamate ([¹⁸F]FRPG) and compared its tumor imaging properties to the 4S-isomer, [¹⁸F]FSPG.

Methods: [¹⁸F]FRPG and [¹⁸F]FSPG uptake was assessed in H460 lung cancer cells, with efflux measured 30 min after removal of exogenous activity. Specificity of [¹⁸F]FRPG for system x_C^- was further examined following transporter inhibition and blocking studies with system x_C^- substrates. [¹⁸F]FRPG and [¹⁸F]FSPG pharmacokinetics was next quantified in mice bearing subcutaneous A549, H460, VCAP and PC3 tumors, with mice bearing A549 tumors imaged by PET/CT. To better-understand differential tumor retention, radiometabolite analysis was performed on tissue and blood samples after imaging. Next, [¹⁸F]FRPG and [¹⁸F]FSPG retention in lipopolysaccharide-treated lungs were compared to an orthotopic H460 lung cancer model. Finally, the sensitivity of [¹⁸F]FRPG to manipulation of the redox environment was examined in cell and in vivo models.

Results: [¹⁸F]FRPG was specifically transported across the plasma membrane by the cystine/glutamate antiporter system x_C^- and retained at high levels in multiple tumor models. Conversely, [¹⁸F]FRPG was rapidly extracted from the blood and cleared from tissues with low system x_C^- expression. Due to its favorable imaging properties, tumor-to-blood ratios ≥10 were achieved with [¹⁸F]FRPG, which were either equal to or greater than [¹⁸F]FSPG. In addition, [¹⁸F]FRPG retention in orthotopic lung tumors with high system x_C^- expression was 2.5-fold higher than inflamed tissue, allowing for clear tumor visualization. In vivo, [¹⁸F]FRPG and [¹⁸F]FSPG were metabolized to a single species, with [¹⁸F]FRPG showing a higher percentage of parent radiotracer in tumors compared to [¹⁸F]FSPG. [¹⁸F]FRPG was sensitive to redox manipulations and tumor retention was reduced following treatment with liposomal doxorubicin in mice bearing ovarian tumors.

Conclusions: Given the fast clearance and low background retention of [¹⁸F]FRPG throughout the body, this radiotracer holds promise for the imaging of system x_C^- activity and treatment response monitoring in tumors of the thorax, abdomen, and head and neck. [¹⁸F]FRPG PET imaging provides a sensitive noninvasive measure of system x_C^- and excellent properties for cancer imaging.

Effect of Systemic Calcitonin Delivery with and Without Adjunct Local Platelet-rich Fibrin Therapy on Osseointegration in Ovariectomized Osteoporotic Rabbits: A Scanning Electron Microscopy-based Study

PURPOSE

It is hypothesised that systemic calcitonin delivery with adjunct local platelet-rich fibrin (PRF) therapy is more effective in augmenting osseointegration than calcitonin delivery alone under experimental osteoporosis conditions. The primary objective of the present experiment was to assess the effect of systemic calcitonin delivery with and without adjunct local PRF therapy on osseointegration in ovariectomised osteoporotic rabbits.

MATERIALS AND METHODS

Thirty female bilaterally ovariectomized rabbits were used. The animals were fed a low-calcium diet to establish a model for osteoporosis. In each animal, 2 implants were bilaterally placed in tibia. The animals were randomly divided equally into 3 groups. In group 1, no treatment was offered (control group). In groups 2 and 3, the animals received intramuscular injections of calcitonin without and with local PRF delivery prior to implant placement, respectively. All animals were euthanised at 12 weeks, and osseointegration was assessed as the gap widths between the bone and implant surface in the cervical, middle and apical third using scanning electron microscopy and energy-dispersive x-ray spectroscopy. The bone-to-implant contact (BIC) was also measured. p < 0.05 was defined as statistically significant.

RESULTS

Gap widths in the cervical (p < 0.001), middle (p < 0.001) and apical third (p < 0.001) were statistically significantly higher in group 1 than groups 2 and 3. Gap widths in the cervical (p < 0.001), middle (p < 0.001) and apical third (p < 0.001) were significantly higher in group 3 than group 2. The mean BIC was statistically significantly higher in the cervical (p < 0.001), middle (p < 0.001) and apical third (p < 0.001) in group 3 compared with groups 2 and 3.

CONCLUSIONS

When used as an adjunct to calcitonin, PRF enhanced osseointegration in an experimental osteoporosis model. However, further well-designed studies with inclusion of additional groups (treatment with PRF alone) are needed.

Acceptability of silver diamine fluoride as interim measure towards untreated dental caries and its impact on ohrqol among children with HIV: Pilot study

Background

Children with HIV are a special group with limited access to care and high prevalence of dental caries. Silver Diamine Fluoride (SDF) is approved universally for the management of asymptomatic carious lesions but research on the psychological impact of black staining is scarce.

Aims

Effect of silver diamine fluoride (SDF) application as an interim caries management on the child's oral health-related quality of life of children with HIV over a period of 4 months until definitive care was provided.

Settings and Design

A pilot study conducted among children with HIV in a care home. It was a pilot trial to check the acceptability of SDF among these children.

Methods and Material

Forty-two children (12.3 ± 3.5 years) participated in this pilot study. Prevalence of caries (DMFT), candidiasis, gingival inflammation, and cervical lymphadenitis was evaluated. OHRQoL inventory (COHIP-SF) was completed by the students at baseline, immediately, 4 months after SDF application.

Statistical Analysis Used

One-way ANOVA with post hoc Tukey HSD test.

Results and Conclusion

Poor oral hygiene was universal and mean DMFT was 3.2 ± 2.5. OHRQoL was not significantly affected at baseline (26.2 ± 6.4), but immediately following SDF application, OHRQoL was significantly poor (48.7 ± 8.2), remained poor even after 4 months (42.6 ± 6.1). Emotional wellbeing was significantly impacted negatively following SDF application (p < 0.001); whereas oral health, functional wellbeing dimensions were not impacted. SDF should be used with caution among special children as the black discoloration of the teeth can cause emotional trauma and negatively impacting their OHRQoL while trying to improve the same.

Anaplastic Thyroid Cancer: a Retrospective analysis of 120 cases

INTRODUCTION

Anaplastic Thyroid Cancer (ATC) is one of the most lethal malignancies with very short survival and extremely poor treatment outcome. ATC accounts for 2-5% of all thyroid cancers worldwide with an annual incidence of about 2 million.

OBJECTIVE

To review the natural history and treatment outcome of ATC patients treated at King Faisal Specialist Hospital and Research Centre (KFSH and RC) located at Riyadh, Saudi Arabia.

MATERIAL AND METHODS

Retrospective review of 120 Saudi cancer patients collected from registry data at KFSH & RC from 1976-2008. Search key words included: thyroid cancer, anaplastic, undifferentiated and not otherwise specified. Search was not restricted to particular age, gender, treatment or tumor size. Demographic information, baseline patient characteristics including date of diagnosis, type of treatment and date of death were obtained from KFSH & RC registry data and Saudi death registry.

RESULTS

A total of 120 cases were identified at our cancer centre from 1976 to 2008. Of these total, 73 were females (60.8%) and 47 were males (39.2%). The average age at diagnosis was 63.34 +/- 12.8 years. Thirty-four patients underwent surgery (28.3%), 52 had a palliative radiation treatment (43.3%) and only 5 had chemotherapy (4.2%). The median survival was 53 days (0-457).

CONCLUSION

Our review proves that ATC is rapidly fatal cancer and is unresponsive to currently available therapeutic options. More research is needed to understand the tumor biology and novel treatment options.

KEYWORDS

thyroid cancer, anaplastic, undifferentiated, radiation treatment, chemotherapy, median survival, Riyadh and Saudi Arabia.

Treatment of aggressive fibromatosis: the experience of a single institution

AIMS

Aggressive fibromatosis is a locally aggressive infiltrative low-grade tumour, although pathologically benign, and it does not metastasise, yet it can cause serious local distressing symptoms by virtue of local destruction and impairment of local function. The aim of this study was to emphasise the role of radiotherapy and adequate surgery in the treatment of fibromatosis in patients presenting with newly diagnosed or recurrent disease and to analyse our treatment results over 15 years for this rare tumour type.

MATERIALS AND METHODS

Fifty-four patients with confirmed diagnosis of aggressive fibromatosis treated at King Faisal Specialist Hospital between 1990 and 2006 were identified from our local cancer registry. Forty-seven patients had surgery: complete resection (R0) in 20 patients, incomplete surgery (R1/2) in 27 patients, and seven patients had biopsy only. Forty-five patients were treated with radiotherapy: 38 patients were treated with postoperative radiotherapy, three patients were treated with preoperative radiotherapy and four patients had radiotherapy as the only treatment. The radiotherapy dose ranged between 45 and 60Gy (median 50.4Gy). Three patients did not receive any form of treatment apart from biopsy, but were still included in the final analysis.

RESULTS

Fifty-two per cent (28/54 patients) of our patient population had tumour recurrence when first presented to King Faisal Specialist Hospital. The median age was 29.5 years (range 2-63 years). The most common site of involvement was the extremities (28 patients). Among the 54 patients (with primary and recurrent presentation) there were 10 local recurrences, all of which were within the original primary site. The 5-year progression-free survival and overall survival rates for the whole group were 75 and 95%, respectively. Univariate and multivariate Cox regression analysis showed that the depth of invasion significantly affected progression-free survival.

CONCLUSION

Aggressive fibromatosis is effectively treated with surgery and postoperative radiotherapy. Patients first presenting with tumour recurrence may still have local tumour control comparable with newly diagnosed patients.

Studies on the in vivo hypoglycemic activities of two medicinal plants used in the treatment of diabetes in Jordanian traditional medicine following intranasal administration

The claimed hypoglycemic activities of Paronychia argentea Lam. (Caryophyllaceae) and Teucrium polium L. (Labiatae), two traditionally widely used medicinal plants in Jordan were evaluated using normoglycemic and alloxan induced hyperglycemic rabbits by intranasal administration of the plant crude extracts (10%) in a vehicle containing 5% (w/w) Pluronic F127. No significant difference was observed between the extract treated and non-treated control animals receiving only water.

Microemulsions are highly effective anti-biofilm agents

AIMS

The demonstration of the antibiofilm effects of pharmaceutical microemulsions.

METHODS AND RESULTS

Microemulsions were prepared as physically stable oil/water systems. Previous work by this group has shown that microemulsions are highly effective antimembrane agents that result in rapid losses of viability in planktonic populations of Pseudomonas aeruginosa and Staphylococcus aureus. In this experiment a microemulsion preparation was used upon established biofilm cultures of Ps. aeruginosa PA01 for a period of 4 h. The planktonic MIC of sodium pyrithione and the planktonic and biofilm MICs of cetrimide were used as positive controls and a biofilm was exposed to a volume of normal sterile saline as a treatment (negative) control. Results indicate three log-cycle reductions in viability within the microemulsion treated biofilm, as compared to those observed in control treatments of similar biofilms (one log-cycle reduction in viabilities).

CONCLUSIONS

The results indicate that the microemulsions are highly effective antibiofilm agents.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that microemulsions may have a role in the treatment of industrial and environmental biofilms.

Microemulsions are membrane-active, antimicrobial, self-preserving systems

Microemulsions are physically stable oil/water systems that have potential use as delivery systems for many pharmaceuticals which are normally of limited use due to their hydrophobicity, toxicity or inability to access the site of action. It has been suggested that microemulsions are self-preserving antimicrobials in their own right, although there is little evidence to support this. In this experiment, microemulsions of various compositions were formulated and tested for their stability and antimicrobial action. The physical stability of the different microemulsions was assessed by centrifugation at 4000g and by storage in a water bath at 37 degrees C for one month, during which no phase separation was observed. The antimicrobial activity of the microemulsions was tested using the compendial method, observation of the kinetics of killing, and transmission electron microscopy (TEM) of microemulsion-exposed cultures of Pseudomonas aeruginosa PA01. These latter experiments on Ps. aeruginosa indicated distinct signs of membrane disruption. The results indicated that the microemulsions are self-preserved, and that their killing of microbial cultures is very rapid and may be the result of membrane activity.

Aqueous solubility of diclofenac diethylamine in the presence of pharmaceutical additives: a comparative study with diclofenac sodium

Aqueous solubility of diclofenac diethylamine (DDEA), a nonsteroidal anti-inflammatory drug currently formulated as a topical emulgel, was studied in the presence of pharmaceutical additives and compared with diclofenac sodium (DS). Electrolytes at low concentrations exhibited a salting-in effect on DDEA with peak solubility that was attributed to the association of DDEA into micelles, followed by a salting-out effect at higher concentrations, by which structure formation by DDEA molecules increased and precipitation occurred. For DS, which is not capable of forming micelles, the salting-out effect was dominant due to the common ion effect. Cosolvents displayed significant enhancement in solubility of both salts except glycerol, which showed a slight increase in solubility of DDEA and a decrease in solubility of DS due to transformation into the less soluble hydrate form. Ethanol and polyethylene glycol (PEG) 400 cosolvent systems at all concentrations showed positive deviations from the log-linear solubility equation. In the case of propylene glycol (PG) cosolvent systems, negative deviations were observed at low volume fractions of cosolvent, while positive deviations were observed at high volume fractions of cosolvent for DS and DDEA. The parent drug, being less ionizable and highly nonpolar, showed negative deviations up to 90% PG content. Thus, the positive deviations for DS and DDEA could be attributed to the more ionizable carboxylic group and its higher ability for hydrogen bonding at higher fractions of cosolvent. Polyvinylpyrrolidone (PVP) and PEG4000 or PEG6000 enhanced the solubility of DS and DDEA, with PVP exerting higher solubilizing efficiency and DS showing better solubility than DDEA. Solubilities of DS in Tween 80 (T80) and Pluronic F-127 (PF127) aqueous solutions were almost similar, while the solubility of DDEA in the presence of T80 was higher than the solubility in the presence of PF127. DS appeared to be located more in the polyoxyethylene mantle of the micelles, while DDEA was located more in the core of the micelles.

Effect of isoorientin isolated from Arum palaestinum on uterine smooth muscle of rats and guinea pigs

The phytochemical investigation of Arum palaestinum resulted in the isolation of two flavone C-glucosides, namely isoorientin (luteolin 6-C-glucoside) and vitexin (apigenin 8-C glucoside). The effects of isoorientin on rat isolated aorta, ileum, trachea and uterus and on guinea-pig uterus were studied. Isoorientin (10(-7)M-6 x 10(-4)M) caused concentration-dependent inhibition of the amplitude and the frequency of the phasic contractions of the rat and guinea-pig uterus but did not affect the isolated aorta, ileum or trachea. The results were discussed in relation to the effects of its aglycone luteolin reported in the literature.

Interaction of two diclofenac acid salts with copolymers of ammoniomethacrylate: effect of additives and release profiles

The copolymer of ammoniomethacrylate Eudragit RL (ERL) interacted with diclofenac acid salts (sodium and diethylamine salts) in aqueous solutions, forming a complex. Sorption experiments were done in aqueous solutions of either sodium lauryl sulfate (SLS), Tween 20, or Tween 80. The SLS competed strongly with the drug, even at low concentrations, and reduced significantly the amount of drug sorbed by ERL. Tweens at high concentrations exhibited two phase profiles: the sorption phase, which was short and during which drug concentration dropped sharply, and the release phase, during which the drug was released slowly over 24 hr and which was accompanied by dispersion of ERL particles into the colloidal dispersion. The interaction was dependent on temperature, ionic strength, and nature of the additives. The extent of interaction in water and phosphate buffer solutions was in the following order: water > pH 6 > pH 7-8. In-vitro dissolution studies of the dried complex were done over 24 hr. In water, the drug remained bound to the polymer. In aqueous surfactant solutions (SLS, Tween 20, and Tween 80) and phosphate buffer at pH 6.8, a linear relationship between drug concentration and the square root of time was obtained, indicating a matrix diffusion-controlled mechanism. However, 100% release was not reached, and resorption was observed in the phosphate buffer solution.

Evaluation of fast disintegrants in terfenadine tablets containing a gas-evolving disintegrant

Effects of four fast disintegrants on the dissolution of terfenadine tablets containing the gas-evolving disintegrant, CaCO3, were evaluated. In addition, effects of presence of starch along with the fast disintegrants on the dissolution of the tablets were examined. Dissolution data were treated to give dissolution parameters which reflected efficiency of the disintegrant combinations. The four fast disintegrants improved disintegration/dissolution of the original formulation. The relative efficiency of improvement was in the order crospovidone > Ac-Di-Sol > Primojel > low substituted hydroxypropylcellulose. The presence of starch advertently affected the role of the fast disintegrants. Scanning electron microscope studies revealed that starch covered the drug-containing granules and other particles of the tablet. pH changes during dissolution of representative tablets in 0.1 N HCl solutions were determined at specific time intervals. The progressive decrease in rates of acid consumption as a function of the amount of starch, along with the SEM studies, suggested that a barrier existed around the tablet particles. The barrier was generated by the swelled starch grains and was responsible for the loss of the dissolution-improving capacity of the fast disintegrants. Furthermore, the barrier interfered with the diffusion of the hydronium ions and therefore, impaired the function of the disintegrant combination.

Evaluation of the gastroprotective effect of Laurus nobilis seeds on ethanol induced gastric ulcer in rats

The possible antiulcerogenic activity of Laurus nobilis seeds was tested on experimentally (ethanol) induced gastric ulcer in rats. The results indicated antiulcerogenic activity for 20 and 40% aqueous extracts as well as for the oily fraction of these seeds. In acute toxicity studies, the aqueous extract was found safe with LD50 compared to oil LD50 0.33 ml/kg body weight.