Importance of tau in cognitive decline as revealed by developmental exposure to lead

Previous reports by us have determined that developmental exposure to the heavy metal lead (Pb) resulted in cognitive impairment in aging wildtype mice, and a latent induction in biomarkers associated with both the tau and amyloid pathways. However, the relationship between these two pathways and their correlation to cognitive performance needs to be scrutinized. Here, we investigated the impact of developmental Pb (0.2%) exposure on the amyloid and tau pathways in a transgenic mouse model lacking the tau gene. Cognitive function, and levels of intermediates in the amyloid and tau pathways following postnatal Pb exposure were assessed on young adult and mature transgenic mice. No significant difference in behavioral performance, amyloid precursor protein (APP), or amyloid beta (Aβ) levels was observed in transgenic mice exposed to Pb. Regulators of the tau pathway were impacted by the absence of tau, but no additional change was imparted by Pb exposure. These results revealed that developmental Pb exposure does not cause cognitive decline or change the expression of the amyloid pathway in the absence of tau. The essentiality of tau to mediate cognitive decline by environmental perturbations needs further investigation.

Tea catechins induce crosstalk between signaling pathways and stabilize mast cells in ulcerative colitis

It is well documented that nutraceuticals, in general, and Green tea catechins, in particular, possess a potential therapeutic value in inflammatory bowel diseases (IBD) due to their anti-oxidative and anti-inflammatory effects. This study aimed to investigate the possible mechanism of action of catechins in a rat model of colitis induced by 2.4.6 trinitrobenzene sulfonic acid (TNBS). Thirty-five young adult Sprague-Dawley rats were divided into four groups: normal control (n=5), catechins (n=9), TNBS (n=9) and TNBS plus catechins (n=12) treated. Catechin in the form of Epigallocatechin-3-gallate (EGCG) was administered daily by intraperitoneal injection, 1 week before the induction date of UC. Biopsies of the descending colon were collected on days 3, 10 and 17, and partly frozen for molecular studies or fixed for light microscopy. The status of intestinal tissue alterations and mast cells number were also assessed, as well as the mRNA expressions of IL-6, TNF-a and NF-kB, and determination of ROS expression. Histological data depicted a significant amelioration in the TNBS- and EGCG-treated rats compared to the non-treated animals. Catechin expressed strong anti-inflammatory and anti-oxidant effects, ameliorated ulcerative colitis and stabilized mast cells. The mechanism of action occurred basically through the NF-kB pathway and possibly through a crosstalk with other pathways.

Early outcomes of spinal growth tethering for idiopathic scoliosis with a novel device: a prospective study with 2 years of follow-up

QUESTIONS/PURPOSES

Adolescent idiopathic scoliosis is a 3D spine deformity that worsens during the whole growth. New methods for spinal growth modulation with flexible spinal implants have been described to avoid progression of the deformity during growth spurt. The main limitations are that no specific ancillaries and devices are available, which makes the surgery technically demanding.

METHODS

We have developed a new method of spinal growth tethering using minimal invasive videothoracoscopic approach. Fixation is performed with staples and synthetic ligament on the lateral aspect of vertebral bodies on main curvature convexity. Patients with progressive thoracic idiopathic scoliosis despite the brace treatment were included. The clinical and radiological examinations were compared before and 2 years after surgery.

RESULTS

Six patients with flexible thoracic curves with a mean age 11.2 ± 1.2 years and a mean Cobb angle 45° ± 10° (35-60) were operated. All were skeletally immature. At last follow-up, the Cobb angle was stable. None of the patient underwent fusion.

CONCLUSIONS

The procedure allowed a stabilization of the deformity during growth spurt. Validated devices and further studies with longer term follow-up are needed to confirm the efficiency of this technique. This small cohort of patients is a source of reflection for further medical devices developments.

LEVEL OF EVIDENCE

Level 4 case series comparing to not randomized studies.

Efficacy of nighttime brace in preventing progression of idiopathic scoliosis of less than 25°

INTRODUCTION

The objective of the present study was to assess, at skeletal maturity, the efficacy of non-operative treatment by isolated nighttime brace in the prevention of progression of progressive idiopathic scoliosis of less than 25°.

HYPOTHESIS

Isolated nighttime brace treatment is effective in the prevention of progression of mild progressive idiopathic scoliosis (Cobb<25°).

MATERIAL AND METHODS

A single-center retrospective study included 142 patients managed by nighttime brace for progressive idiopathic scoliosis with Cobb angle<25°, with assessment at skeletal maturity. Mean Cobb angle at start of treatment was 15.5° (range, 10-25°). Mean values for Cobb angle and sagittal parameters before treatment and at skeletal maturity were compared on Student t-test. Change in Cobb angle over time was also analyzed.

RESULTS

Mean Cobb angle at skeletal maturity was 16.3°, showing significant increase over baseline (15.5°; P=0.04), although the difference was less than the uncertainty of measurement (±6°). In baseline Risser 0 or 1, mean change in Cobb angle at skeletal maturity (16.2°) was not significant (P=0.1). Cobb angle diminished in 26 cases (18%), increased in 24 (17%) and was unchanged in 92 (65%).

CONCLUSION

The present study confirmed the efficacy of non-operative treatment by nighttime brace in mild progressive idiopathic scoliosis (<25°) in a large majority of cases. A nighttime brace thus seems to be an effective option for the treatment of adolescent scoliosis, ensuring a safe curve of around 20°.

LEVEL OF EVIDENCE

Level IV, retrospective study.

[Pitfalls in the diagnosis of occult elbow fractures in children]

Elbow injuries are frequent but occult fractures are difficult to diagnose on x-rays. However, any delay in the diagnosis may severely impair the prognosis of some fractures. Simple tips may help the clinician read x-rays properly and avoid the classical pitfalls of elbow injuries in children. The chronology of appearance of ossification nuclei around the elbow is important to distinguish normal features from abnormality. Drawing simple geometric constructions on the x-rays may clarify most occult elbow fractures in children.

Introduction and enzootic of A/H5N1 in Egypt: Virus evolution, pathogenicity and vaccine efficacy ten years on

It is almost a decade since the highly pathogenic H5N1 avian influenza virus (A/H5N1) of clade 2.2.1 was introduced to Egypt in 2005, most likely, via wild birds; marking the longest endemic status of influenza viruses in poultry outside Asia. The endemic A/H5N1 in Egypt still compromises the poultry industry, poses serious hazards to public health and threatens to become potentially pandemic. The control strategies adopted for A/H5N1 in Egyptian poultry using diverse vaccines in commercialized poultry neither eliminated the virus nor did they decrease its evolutionary rate. Several virus clades have evolved, a few of them disappeared and others prevailed. Disparate evolutionary traits in both birds and humans were manifested by accumulation of clade-specific mutations across viral genomes driven by a variety of selection pressures. Viruses in vaccinated poultry populations displayed higher mutation rates at the immunogenic epitopes, promoting viral escape and reducing vaccine efficiency. On the other hand, viruses isolated from humans displayed changes in the receptor binding domain, which increased the viral affinity to bind to human-type glycan receptors. Moreover, viral pathogenicity exhibited several patterns in different hosts. This review aims to provide an overview of the viral evolution, pathogenicity and vaccine efficacy of A/H5N1 in Egypt during the last ten years.

Rhus coriaria suppresses angiogenesis, metastasis and tumor growth of breast cancer through inhibition of STAT3, NFκB and nitric oxide pathways

Recently, we reported that Rhus coriaria exhibits anticancer activities by promoting cell cycle arrest and autophagic cell death of the metastatic triple negative MDA-MB-231 breast cancer cells. Here, we investigated the effect of Rhus coriaria on the migration, invasion, metastasis and tumor growth of TNBC cells. Our current study revealed that non-cytotoxic concentrations of Rhus coriaria significantly inhibited migration and invasion, blocked adhesion to fibronectin and downregulated MMP-9 and prostaglandin E₂ (PgE2). Not only did Rhus coriaria decrease their adhesion to HUVECs and to lung microvascular endothelial (HMVEC-L) cells, but it also inhibited the transendothelial migration of MDA-MB-231 cells through TNF-α-activated HUVECs. Furthermore, we found that Rhus coriaria inhibited angiogenesis, reduced VEGF production in both MDA-MB-231 and HUVECs and downregulated the inflammatory cytokines TNF-α, IL-6 and IL-8. The underlying mechanism for Rhus coriaria effects appears to be through inhibiting NFκB, STAT3 and nitric oxide (NO) pathways. Most importantly, by using chick embryo tumor growth assay, we showed that Rhus coriaria suppressed tumor growth and metastasis in vivo. The results described in the present study identify Rhus coriaria as a promising chemopreventive and therapeutic candidate that modulate triple negative breast cancer growth and metastasis.

Percutaneous cholecystostomy is safe and effective option for acute calculous cholecystitis in select group of high-risk patients

PURPOSE

In high-risk patients with acute calculous cholecystitis (ACC), percutaneous cholecystostomy (PC) can serve as a bridging option to cholecystectomy [laparoscopic cholecystectomy (LC)] or as definitive treatment. The purpose of this study was to identify predictors of the need for permanent PC.

METHODS

Data from 257 PCs performed for ACC (mean age 67.3 ± 14) was collected for a 10-year period. Demographic and clinical characteristics at initial admission, co-morbidities were analyzed. Patients who underwent interval LC were defined as the surgery group (SG; n = 163, 63.4 %) and the remaining patients as the non-SG (NSG; n = 94, 36.6 %).

RESULTS

Patients in the SG were significantly younger and had a shorter length of hospital stay (p < 0.01). The rate of coronary artery disease (CAD; 63.2 vs. 20.2 %), chronic renal failure (14.9 vs. 6.1 %), and the mean number of co-morbidities (2.2 vs. 1.4) were significantly higher in the NSG. Sepsis at admission was more common in the NSG (19.1 vs. 4.9 %, p < 0.001). 56 patients (34.4 %) in the SG and 24 patients (25.5 %) in the NSG developed tube-related complications. In hospital mortality was similar between the groups. Multivariate analysis showed that age ≥75, increased alkaline phosphatase (ALK-P), history of CAD, were predictors of PC as a definite treatment in this high-risk group of patients with ACC.

CONCLUSIONS

High operative risk due to older age and CAD preclude LC in more than one-third of patients following PC especially presenting with sepsis and elevated ALK-P. This study suggests that PC could be a safe treatment option in this select group of high-risk patients.

Carnosol induces ROS-mediated beclin1-independent autophagy and apoptosis in triple negative breast cancer

Background

In this study we investigated the in vitro and in vivo anticancer effect of carnosol, a naturally occurring polyphenol, in triple negative breast cancer.

Results

We found that carnosol significantly inhibited the viability and colony growth induced G2 arrest in the triple negative MDA-MB-231. Blockade of the cell cycle was associated with increased p21/WAF1 expression and downregulation of p27. Interestingly, carnosol was found to induce beclin1-independent autophagy and apoptosis in MDA-MB-231 cells. The coexistence of both events, autophagy and apoptosis, was confirmed by electron micrography. Induction of autophagy was found to be an early event, detected within 3 h post-treatment, which subsequently led to apoptosis. Carnosol treatment also caused a dose-dependent increase in the levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2). Moreover, we show that carnosol induced DNA damage, reduced the mitochondrial potential and triggered the activation of the intrinsic and extrinsic apoptotic pathway. Furthermore, we found that carnosol induced a dose-dependent generation of reactive oxygen species (ROS) and inhibition of ROS by tiron, a ROS scavenger, blocked the induction of autophagy and apoptosis and attenuated DNA damage. To our knowledge, this is the first report to identify the induction of autophagy by carnosol.

Conclusion

In conclusion our findings provide strong evidence that carnosol may be an alternative therapeutic candidate against the aggressive form of breast cancer and hence deserves more exploration.

Estrogens control inflammation in experimental colitis

There is now a wealth of experimental evidence indicating that the deficit in endogenous estrogen facilitates the onset of inflammation that can be antagonized by estrogen replacement therapy. This work investigated the role of estrogen in the control of intestinal inflammation in a panel of colitis models, focusing on the morphological changes, the activity of mast cells, the expression of cytokines (IL-1beta, IL-6, and TNF-alpha), fibronectin and reactive oxygen species. Two hundred adult male rats were divided into 4 groups: colitis was induced in Group I and Group II but only the latter was treated with estrogen; Group III received estrogen only, and Group IV saline. Colitis was induced in 4 models using: iodoacetamide; iodoacetamide + enteropathogenic E. coli; 2, 4, 6-Trinitrobenzene sulfonic acid; and dextran sulfate sodium salt. Macroscopic and microscopic evaluations of abdominal structures as well as molecular analysis were made on days 7, 14, 28 and 56. There was a significant improvement in the health condition of the estrogen-treated rats: the inflammation scores were reduced by at least 10-15&#x0025;, the number of mast cells in the colon decreased by 30&#x0025;, fibronectin expression was only 50&#x0025; and reactive oxygen species decreased by 30&#x0025;. In addition, there was a significant decrease in TNF-alpha, IL-6 and IL-1beta expression by about 25&#x0025;. In conclusion, there was an improvement in the inflammatory status in all estrogen-treated groups through the duration of the experiment at all-time points. In addition, there was less tissue necrosis as depicted by less fibronectin and a marked antioxidant effect.

A phase II randomized trial of induction chemotherapy versus no induction chemotherapy followed by preoperative chemoradiation in patients with esophageal cancer

BACKGROUND

The contribution of induction chemotherapy (IC) before preoperative chemoradiation for esophageal cancer (EC) is not known. We hypothesized that IC would increase the rate of pathologic complete response (pathCR).

METHODS

Trimodality-eligibile patients were randomized to receive no IC (Arm A) or IC (oxaliplatin/FU; Arm B) before oxaliplatin/FU/radiation. Surgery was attempted ∼5-6 weeks after chemoradiation. The pathCR rate, post-surgery 30-day mortality, overall survival (OS), and toxic effects were assessed. Bayesian methods and Fisher's exact test were used.

RESULTS

One hundred twenty-six patients were randomized dynamically to balance the two arms for histology, baseline stage, gender, race, and age. Fifty-five patients in Arm A and 54 in Arm B underwent surgery. The median actuarial OS for all patients (54 deaths) was 45.62 months [95% confidence interval (CI), 27.63-NA], with median OS 45.62 months (95% CI 25.56-NA) in Arm A and 43.68 months (95% CI 27.63-NA) in Arm B (P = 0.69). The pathCR rate in Arm A was 13% (7 of 55) and 26% (14 of 54) in Arm B (two-sided Fisher's exact test, P = 0.094). Safety was similar in both arms.

CONCLUSIONS

These data suggest that IC produces non-significant increase in the pathCR rate and does not prolong OS. Further development of IC before chemoradiation may not be beneficial. Clinical trial no.: NCT 00525915 (www.clinicaltrials.gov).

Anti-metastatic and anti-tumor growth effects of Origanum majorana on highly metastatic human breast cancer cells: inhibition of NFκB signaling and reduction of nitric oxide production

Background

We have recently reported that Origanummajorana exhibits anticancer activity by promoting cell cycle arrest and apoptosis of the metastatic MDA-MB-231 breast cancer cell line. Here, we extended our study by investigating the effect of O. majorana on the migration, invasion and tumor growth of these cells.

Results

We demonstrate that non-cytotoxic concentrations of O. majorana significantly inhibited the migration and invasion of the MDA-MB-231 cells as shown by wound-healing and matrigel invasion assays. We also show that O. majorana induce homotypic aggregation of MDA-MB-231 associated with an upregulation of E-cadherin protein and promoter activity. Furthermore, we show that O. majorana decrease the adhesion of MDA-MB-231 to HUVECs and inhibits transendothelial migration of MDA-MB-231 through TNF-α-activated HUVECs. Gelatin zymography assay shows that O. majorana suppresses the activities of matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9). ELISA, RT-PCR and Western blot results revealed that O. majorana decreases the expression of MMP-2, MMP-9, urokinase plasminogen activator receptor (uPAR), ICAM-1 and VEGF. Further investigation revealed that O. majorana suppresses the phosphorylation of IκB, downregulates the nuclear level of NFκB and reduces Nitric Oxide (NO) production in MDA-MB-231 cells. Most importantly, by using chick embryo tumor growth assay, we also show that O. majorana promotes inhibition of tumor growth and metastasis in vivo.

Conclusion

Our findings identify Origanummajorana as a promising chemopreventive and therapeutic candidate that modulate breast cancer growth and metastasis.

Spica cast as an alternative to general anesthesia for lower limb MRI in young children

Background

The conventional approach for MRI procedures in very young children is to use general anesthesia which comes with inherent risks. Non-pharmacological strategies to reduce anxiety in children have also been described, but they all require patient cooperation. The purpose of the study was to evaluate the ability to complete diagnosis using temporary spica cast immobilization (TSCI) in children less than 3 years old undergoing MRI procedures for lower limb disorders.

Materials and methods

A retrospective review identified 14 children under 3 years old that had required an MRI for a lower limb disorder, using TSCI. The MRI procedure was performed for evaluation of hip dysplasia, bone infections, limping, evaluation of soft tissue tumor and femoral head osteonecrosis. A spica cast was fitted by the pediatric orthopedic team. The MRI procedure was subsequently performed.

Results

Diagnosis was achieved in all cases. The radiologist identified movement artifacts (14 %) that did not impair the image quality enough to prevent interpretation.

Conclusion

TSCI is a safe, effective and costless procedure avoiding general anesthesia for young patients under 3 years old who require MRI for pelvis or lower limb disorders.

Level of evidence

IV.

Endometriosis and cancer: what do we know?

Endometriosis is the presence of endometriotic tissue outside of the uterus, composed of endometriotic glands and stroma. It affects between 10% to 12% of women in reproductive age. It presents with dysmenorrhea, dyspareunia, chronic pelvic pain, infertility, urinary or digestive symptoms. Diagnosis is based on clinical suspicion, clinical exam, pelvic ultrasound or pelvic magnetic resonance, and confirmed by laparoscopy with pathology studies. Its management is better understood nowadays. However, its association with neoplasia has been questioned for many years. It probably plays a role in the etiology of gynecological cancers, mainly ovarian neoplasia. In our review, we separately compared endometriosis and endometrioma to cancer, in terms of mutual causality, common risk factors, distinction based on histological findings, in addition to molecular and genetic pathways behind this association. This article reviews the English literature for studies on the association between endometriosis and gynecological cancers. Additional reports were collected by systematically reviewing all references from retrieved papers.

Mitotic arrest and apoptosis in breast cancer cells induced by Origanum majorana extract: upregulation of TNF-α and downregulation of survivin and mutant p53

Background

In the present study, we investigated the effect of Origanum majorana ethanolic extract on the survival of the highly proliferative and invasive triple-negative p53 mutant breast cancer cell line MDA-MB-231.

Results

We found that O. majorana extract (OME) was able to inhibit the viability of the MDA-MB-231 cells in a time- and concentration-dependent manner. The effect of OME on cellular viability was further confirmed by the inhibition of colony growth. We showed, depending on the concentration used, that OME elicited different effects on the MDA-MB 231 cells. Concentrations of 150 and 300 µg/mL induced an accumulation of apoptotic–resistant population of cells arrested in mitotis and overexpressing the cyclin-dependent kinase inhibitor, p21 and the inhibitor of apoptosis, survivin. On the other hand, higher concentrations of OME (450 and 600 µg/mL) triggered a massive apoptosis through the extrinsic pathway, including the activation of tumor necrosis factor-α (TNF-α), caspase 8, caspase 3, and cleavage of PARP, downregulation of survivin as well as depletion of the mutant p53 in MDA-MB-231 cells. Furthermore, OME induced an upregulation of γ-H2AX, a marker of double strand DNA breaks and an overall histone H3 and H4 hyperacetylation.

Conclusion

Our findings provide strong evidence that O. majorana may be a promising chemopreventive and therapeutic candidate against cancer especially for highly invasive triple negative p53 mutant breast cancer; thus validating its complementary and alternative medicinal use.

Stabilization of HIF-2α through redox regulation of mTORC2 activation and initiation of mRNA translation

HIF-2alpha plays a critical role in renal tumorigenesis. HIF-2alpha is stabilized in Von Hippel-Lindau (VHL)-deficient renal cell carcinoma through mechanisms that require ongoing mRNA translation. Mammalian target of Rapamycin (mTOR) functions in two distinct complexes, Raptor-associated mTORC1 and Rictor-associated mTORC2. Rictor-associated mTORC2 complex has been linked to maintaining HIF-2alpha protein in the absence of VHL, however the mechanisms remain to be elucidated. Although Raptor-associated mTORC1 is a known key upstream regulator of mRNA translation, initiation and elongation, the role of mTORC2 in regulating mRNA translation, is not clear. Complex assembly of the mRNA cap protein, eIF4E, with activators (eIF4G) and inhibitors (4E-BP1) are rate-limiting determinants of mRNA translation. Our laboratory has previously demonstrated that reactive oxygen species, mediated by p22^phox-based Nox oxidases, are enhanced in VHL-deficient cells and play a role in the activation of Akt on S473, a site phosphorylated by the mTORC2 complex. In this study, we examined the role of Rictor-dependent regulation of HIF-2alpha through eIF4E-dependent mRNA translation and examined the effects of p22^phox-based Nox oxidases on TORC2 regulation. We demonstrate for the first time that mTORC2 complex stability and activation is redox sensitive and further defined a novel role for p22^phox-based Nox oxidases in eIF4E-dependent mRNA translation through mTORC2. Furthermore, we provide the first evidence that silencing of p22^phox reduces HIF-2alpha-dependent gene targeting in vitro and tumor formation in vivo. The clinical relevance of these studies is demonstrated.