Endoplasmic reticulum stress in Alzheimer's disease: Molecular mechanisms and therapeutic prospects

Alzheimer's disease (AD) is a progressive neurodegenerative condition that leads to memory loss and cognitive impairment over time. It is characterized by protein misfolding as well as prolonged cellular stress, such as perturbing calcium homeostasis and redox management. Numerous investigations have proven that endoplasmic reticulum failure may exhibit exacerbation of AD pathogenesis in AD patients, in-vivo and in-vitro models. The endoplasmic reticulum (ER) participates in a variety of biological functions including folding of protein, quality control, cholesterol production, and maintenance of calcium balance. A diverse range of physiological, pathological and pharmacological substances can interfere with ER activity and thus lead to exaggeration of ER stress. The unfolded protein response (UPR), an intracellular signaling network is stimulated due to ER stress. Three stress sensors found in the endoplasmic reticulum, the PERK, ATF6, and IRE1 transducers detect protein misfolding in the ER and trigger UPR, a complex system to maintain homeostasis. ER stress is linked to many of the major pathological processes that are seen in AD, including presenilin1 and 2 (PS1 and PS2) gene mutation, tau phosphorylation and β-amyloid formation. The role of ER stress and UPR in the pathophysiology of AD implies that they can be employed as potent therapeutic target. This study shows the relationship between ER and AD and how the pathogenesis of AD is influenced by the impact of ER stress. An effective method for the prevention or treatment of AD may involve therapeutic strategies that modify ER stress pathways.

Aggressive bougie dilatation and intralesional steroids is effective in refractory benign esophageal strictures secondary to corrosive ingestion

Endoscopic dilatation of corrosive esophageal strictures is effective, but some patients are refractory to it and require long-term repeated dilatations. The present study was carried out to analyze whether rigorous schedule of endoscopic bougie dilatation along with intralesional injection of triamcinolone in patients refractory to endoscopic dilatation alone could decrease the number and frequency of endoscopic dilatations. The inclusion criterion for this prospective study was patients with refractory corrosive esophageal stricture of any age group. Refractory benign esophageal stricture is defined as an anatomic fibrotic esophageal restriction with inability to achieve dilatation of ≥14 mm or to maintain dilatation for 4 weeks once ≥14 mm diameter is achieved. The patients were followed up prospectively for 1 year. Patients with refractory strictures were subjected to weekly bougie dilatation (Savary-Gilliard) of the strictures along with injections of intralesional triamcinolone (40 mg/mL, 1 mL diluted in 1 mL of saline, 0.5 mL injected per quadrant of stricture) for consecutive 5 weeks, referred to as rigorous schedule. Further dilatation was done on an 'on-demand' basis. Eleven patients were enrolled for the study. Dysphagia score improved from pre-intervention score of 3.54 ± 0.52 to 0.45 ± 0.52 post-intervention (P < 0.001). The maximum dilatation achieved pre-intervention was 9.90+1.04 mm Savary-Gilliard and post-intervention significantly improved to 14.7 + 0.7 mm Savary-Gilliard (P < 0.001). The periodic dilatation index defined as number of dilatations per month also significantly improved from pre-intervention score of 2.54 ± 1.06 to post-intervention score of 0.19 + 0.13 (P < 0.001). No adverse effects were reported by the patients. Rigorous weekly schedule of bougie dilatation and intralesional triamcinolone in combination is safe and effective in achieving significant dilatation, reducing the frequency dilatations, maintaining dilatation and improving dysphagia till 1 year of follow-up.

Unstable Angina: A Serious Adverse Event following Gemcitabine-Cisplatin Based Chemotherapy

A 29 year male, with an inoperable adenocarcinoma of gall bladder was initiated on gemcitabine and a platinum compound based chemotherapy. During 4th cycle of chemotherapy, patient complained of chest pain following cisplatin and gemcitabine infusion. ECG was suggestive of acute coronary syndrome, which was successfully managed by antianginal therapy. Fifth cycle of chemotherapy was uneventful. Patient died of cardiovascular collapse before receiving the 6th cycle of chemotherapy. As per Naranjo adverse drug reaction probability scale, causal association of the event with cisplatin and gemcitabine was probable and possible respectively. It is advised to routinely assess the cardiovascular status of patients before and during cisplatin and/or gemcitabine based chemotherapy.

Genotoxicity evaluation of hospital wastewaters

In hospitals a large variety of substances are in use for medical purposes such as diagnostics and research. After application, diagnostic agents, disinfectants and excreted non-metabolized pharmaceuticals by patients reach the wastewater. Indeed, some of the substances found in wastewaters are genotoxic and are suspected to be a possible cause of the cancers observed in the last decades. Genotoxicity tests are an excellent means to study the toxicity and the risk associated with these releases. This paper points out the areas of concern for hospital wastewater disposal and reports the findings of genotoxicity tests for hospital effluents from 3 major hospitals in Delhi, namely All India Institute of Medical Sciences, Apollo and Escorts. Mutagenicity of hospital wastewaters from effluent treatment plants (before and after treatment) was studied. The results of this study show that the genotoxicity of hospital wastewaters is highly reduced after the treatment process. This study calls for establishment of advanced and effective effluent treatment plants in the hospitals, which are merely dumping the wastewaters in the municipal sewerage system. The results of this study call for further detailed study in this area.