Cellular uptake and concentrations of tamoxifen upon administration in poly(ε-caprolactone) nanoparticles

Purpose: In an attempt to increase the local concentration of tamoxifen in estrogen receptor positive breast cancer cells, we have prepared and characterized poly (ε-caprolactone) (PCL) nanoparticle formulation. Methods: PCL (mol wt 14,800 daltons) nanoparticles were prepared by the solvent displacement method in acetonewater system in the presence of Pluronic F-68. PCL nanoparticles, labeled with rhodamine 123, were incubated with MCF-7 estrogen receptor positive breast cancer cells to determine uptake, intracellular distribution, and localization as a function of time. Intracellular drug concentrations over a specified period of time using different initial doses were examined using tritiated [³H]-tamoxifen. Results: A significant fraction of the administered rhodamine 123-loaded PCL nanoparticles was found in the perinuclear region of the MCF-7 cells, where estrogen receptors are also localized, after 1 hour of incubation. Measurements of the intracellular concentrations revealed that most of the administered nanoparticle dose was internalized within the first 30 minutes of incubation, and the uptake followed saturable transport kinetics. Conclusion: Results of this study show that PCL nanoparticles were rapidly internalized in MCF-7 cells and intracellular tamoxifen concentrations followed a saturable process. This approach may provide better therapeutic benefit by delivering the drug locally, near the tumor cells, for a longer period of time.     

The oral neurokinin-1 antagonist aprepitant for the prevention of chemotherapy-induced nausea and vomiting: a multinational, randomized, double-blind, placebo-controlled trial in patients receiving high-dose cisplatin--the Aprepitant Protocol 052 Study Group.

PURPOSE: In early clinical trials with patients receiving highly emetogenic chemotherapy, the neurokinin antagonist aprepitant significantly enhanced the efficacy of a standard antiemetic regimen consisting of a type-three 5-hydroxytryptamine antagonist and a corticosteroid. This multicenter, randomized, double-blind, placebo-controlled phase III study was performed to establish definitively the superiority of the aprepitant regimen versus standard therapy in the prevention of chemotherapy-induced nausea and vomiting (CINV). PATIENTS AND METHODS: Patients receiving cisplatin > or = 70 mg/m2 for the first time were given either standard therapy (ondansetron and dexamethasone on day 1; dexamethasone on days 2 to 4) or an aprepitant regimen (aprepitant plus ondansetron and dexamethasone on day 1; aprepitant and dexamethasone on days 2 to 3; dexamethasone on day 4). Patients recorded nausea and vomiting episodes in a diary. The primary end point was complete response (no emesis and no rescue therapy) on days 1 to 5 postcisplatin, analyzed by a modified intent-to-treat approach. Treatment comparisons were made using logistic regression models. Tolerability was assessed by reported adverse events and physical and laboratory assessments. RESULTS: The percentage of patients with complete response on days 1 to 5 was significantly higher in the aprepitant group (72.7% [n = 260] v 52.3% in the standard therapy group [n = 260]), as were the percentages on day 1, and especially on days 2 to 5 (P <.001 for all three comparisons). CONCLUSION: Compared with standard dual therapy, addition of aprepitant was generally well tolerated and provided consistently superior protection against CINV in patients receiving highly emetogenic cisplatin-based chemotherapy.     

Global myocardial revascularization without cardiopulmonary bypass using innovative techniques for myocardial stabilization and perfusion

BACKGROUND: In off-pump coronary bypass grafting (CABG), invasiveness is reduced but technically perfect anastomosis is jeopardized by cardiac motion and the need to hurry to reduce the time of ischemia. Also, a major cause of postoperative morbidity and mortality is ungrafted circumflex coronary artery disease. We have devised a means of overcoming these shortcomings and performing multivessel CABG. The objective of this study was to assess the safety and efficacy of our technique. METHODS: One hundred patients with severe triple-vessel disease underwent multivessel off-pump CABG. For cardiac stabilization, a combination of local pericardial stabilization sutures and lifting and rotating the heart by means of posterior pericardial sutures were used. For myocardial perfusion, a technique of retrograde coronary sinus perfusion by arterial blood from the ascending aorta was used. RESULTS: Each patient received an average of 3.8 grafts (range 3 to 5). Complications included conversion to cardiopulmonary bypass (CPB) in 1 patient and a perioperative myocardial infarction in the same patient. In all other patients we were able to perform a satisfactory grafting in all territories with no operative mortality. Rapid recovery allowed 95% of our patients to resume normal activity within 1 month. A predischarge graft angiogram in 35 patients showed 97.8% patency. CONCLUSIONS: These results suggest that off-pump CABG with our techniques is effective and safe. Early clinical outcome and excellent patency rates suggest its more widespread use in selected cases.     

Prevalence of asthma in urban school children in Jaipur, Rajasthan

A cross sectional survey of 3321 school going children (5–15 years) using modified ISAAC questionnaire in Jaipur city showed 7.59% children to have asthma (in last 12 months) and 8.4% wheezing in last 12 months. Only 5.3 % children had “physician diagnosed asthma ever” suggesting under diagnoses.     

Microbial keratitis following vegetative matter injury

The purpose of the present study was to analyze the microbiological profile of cases of keratitis following trauma with vegetative matter in a tertiary care center. A retrospective review of the medical records of 49 patients with keratitis following vegetative matter injury over a 3-month period was performed. All patients underwent corneal scraping for smears and inoculation onto various culture media. The microbiological profile was based on the smear and culture reports. For patients who were culture-negative, outcome after standard empirical antibacterial therapy as per hospital protocol was analyzed. Thirteen patients with corneal ulcers had fungal etiology, eight had bacterial etiology, and two had protozoal etiology, while 13 patients were polymicrobial and 13 were culture-negative. Polymicrobial infections were mainly bacterial (eight cases), and the remaining five cases had coexistent fungal and bacterial etiology. The treatment was directed to the specific organism and patients improved with medical or surgical therapy. Only a third of culture-negative cases showed fungal etiology on biopsy or histopathology after keratoplasty while a third showed improvement with therapy. Corneal infections following vegetative matter trauma show a varied etiological profile; however, bacterial and polymicrobial infections are more prevalent. Empirical anti-fungal therapy, as commonly practiced, must be avoided in cases with vegetative matter injury.     

Key changes in denervated muscles and their impact on regeneration and reinnervation

The neuromuscular junction becomes progressively less receptive to regenerating axons if nerve repair is delayed for a long period of time. It is difficult to ascertain the denervated muscle＇s residual receptivity by time alone. Other sensitive markers that closely correlate with the extent of denervation should be found. After a denervated muscle develops a fibrillation potential, muscle fiber conduction velocity, muscle fiber diameter, muscle wet weight, and maximal isometric force all decrease; remodeling increases neuromuscular junction fragmentation and plantar area, and expression of myogenesis-related genes is initially up-regulated and then down-regulated. All these changes correlate with both the time course and degree of denervation. The nature and time course of these denervation changes in muscle are reviewed from the literature to explore their roles in assessing both the degree of detrimental changes and the potential success of a nerve repair. Fibrillation potential amplitude, muscle fiber conduction velocity, muscle fiber diameter, mRNA expression levels of myogenic regulatory factors and nicotinic acetylcholine receptor could all reflect the severity and length of denervation and the receptiveness of denervated muscle to regenerating axons, which could possibly offer an important clue for surgical choices and predict the outcomes of delayed nerve repair.