Microencapsulated dopamine (DA)-induced restitution of function in 6-OHDA-denervated rat striatum in vivo: comparison between two microsphere excipients.

Biodegradable controlled-release microsphere systems made with the biocompatible biodegradable polyester excipient poly [DL lactide-co-glycolide] constitute an exciting new technology for drug delivery to the central nervous system (CNS). The present study describes functional observations indicating that implantation of dopamine (DA) microspheres encapsulated within two different polymer excipients into denervated-striatal tissue assures a prolonged release of the transmitter in vivo. Moreover, in this regard, the results show that there were clear cut temporal differences in the effect of the two DA microsphere formulations compared in this study, probably reflecting variations in the actual composition (i.e., lactide to glycolide ratio) of the two copolymer excipients examined. This technology has considerable potential for basic research with possible clinical application.     

Genetic damage detected in CD-1 mouse pups exposed perinatally to 3'-azido-3'-deoxythymidine or dideoxyinosine via maternal dosing, nursing, and direct gavage: II. Effects of the individual agents compared to combination treatment

We previously reported extraordinary increases in micronucleated erythrocytes in CD-1 mouse pups exposed to 3'-azido-3'-deoxythymidine (AZT) and dideoxyinosine (ddI; 50/250, 75/375, 150/750 mg/kg/day AZT/ddI) by gavage throughout gestation and lactation, followed by direct pup dosing beginning postnatal day (PND) 4 (Bishop et al. [2004]: Environ Mol Mutagen 43: 3-9). That study was conducted to explore the potential for genetic damage in newborns exposed perinatally to antiretrovirals in order to reduce maternal-infant transmission of HIV-1. Because dramatic increases in frequencies of micronucleated erythrocytes were seen in exposed pups, additional studies were conducted to clarify the relative contribution of each drug to the observed damage. Pregnant CD-1 mice were administered AZT (50, 75, 150 mg/kg/day) or ddI (250, 375, 750 mg/kg/day) by gavage twice daily in equal fractions beginning prior to mating and continuing throughout gestation and lactation. Direct pup dosing (same regimens) began on PND 4. Peripheral blood erythrocytes of male pups were screened for micronuclei on PNDs 1, 4, 8, and 21. Significant increases in micronucleated erythrocytes were observed in pups and dams exposed to AZT at all doses and sampling times. The highest micronucleus levels were observed in pups on PND 8 after the initiation of direct dosing. In contrast, effects seen in pups and dams treated with ddI were minimal. These results demonstrate that AZT, a component of many anti-HIV combination therapies, induces chromosomal damage in perinatally exposed neonatal mice. Comparison of micronucleated cell frequencies induced by AZT alone or in combination with ddI suggests that ddI potentiates AZT-induced chromosomal damage following direct exposure.     

Effect of treatment protocol and sample time on the frequencies of micronucleated polychromatic erythrocytes in mouse bone marrow and peripheral blood

Studies were conducted to evaluate the effect of experimental protocol on the ability of benzidine (BZD), dimethylbenzanthracene (DMBA) and mitomycin C (MMC), administered by intraperitoneal injection, to induce micronuclei in polychromatic erythrocytes (PCE) of B6C3F1 mice. Three different treatment/sampling protocols were used, involving from one to three consecutive daily treatments and from three to one, respectively, consecutive daily samplings beginning 24 h after the last injection. DMBA and MMC elicited a significant micronucleus response in all three experimental protocols, while BZD induced a significant response only in the multiple injection protocols. Of the three protocols, the 3-day injection/single sample time protocol offers the greatest efficiency in minimizing the number of animals required in a study, in decreasing the time needed for scoring and in simplifying the statistical analysis. In addition, a comparison of the frequency of micronucleated PCE in peripheral blood and bone marrow following the treatment of mice with either BZD or DMBA suggests that, following a three injection protocol, either tissue can be used with equal efficacy.     

The importance of teamwork for outpatient parenteral antibiotic therapy

A variety of treatment models can be constructed to provide intravenous antibiotic therapy outside the hospital. The type and details of each model must be adapted to local needs and resources, but those that coordinate the resources of all the primary members of the team necessary to care for patients, offer the greatest potential for a safe and efficient programme. We believe that the teamwork of the physician, nurse, and pharmacist in our clinic-based, physician-directed model can provide a safe and effective service, which is appreciated by the patients we care for.     

Annuloplasty in children and young adolescents with severe rheumatic mitral insufficiency

Eleven patients aged 8 to 15 years underwent measured asymmetrical annuloplasty for severe mitral regurgitation in the years 1961 through 1966. They had had a total of 20 attacks of acute rheumatic fever. The intervals between the last attack of acute rheumatic fever and operation ranged from 2 to 8 years. The criteria for surgery were congestive failure and progressive cardiac enlargement. Using the hydraulic formula of Gorlin, a mitral annuloplasty was tailored to the size of each patient so that insufficiency was eliminated without producing hemodynamically significant stenosis. In this group of 11 children there has been one death. The majority of our 11 patients reacquired murmurs of mitral regurgitation. Satisfactory results, however, are not dependent on complete hemodynamic correction. All patients have improved remarkably and have sustained this improvement up to 7 years. These results suggest that mitral annuloplasty should be the operation of choice in children with severe mitral regurgitation.     

Evidence of impaired pain modulation in adolescents with idiopathic scoliosis and chronic back pain

BACKGROUND CONTEXT

Although 40% of adolescent idiopathic scoliosis (AIS) patients present with chronic back pain, the pathophysiology and underlying pain mechanisms remain poorly understood. We hypothesized that development of chronic pain syndrome in AIS is associated with alterations in pain modulatory mechanisms.

Comparative costs of ertapenem and piperacillin-tazobactam in the treatment of diabetic foot infections.

PURPOSE: To evaluate potential cost savings, trial data were used to determine the clinical outcomes for i.v. ertapenem given once daily and i.v. piperacillin-tazobactam given every six hours daily in treating diabetic foot infections. METHODS: A cost-minimization analysis (CMA) was conducted on the drug-dosing data of the subset of patients enrolled in a recent double-blind randomized trial who were treated solely as inpatients and were clinically evaluable at fi nal assessment (n = 99). Cost per dose was calculated from (a) average hospital acquisition price per dose for ertapenem ($40.52) or piperacillin-tazobactam ($13.58), (b) average U.S. wages and benefits for labor, based on nine published time-and-motion studies of i.v. antibiotic preparation and administration ($3.10), and (c) consumable supplies, using a 40% discount off the manufacturer list price ($2.90). For each patient, the actual number of antibiotic doses given was multiplied by total cost per dose. RESULTS: There were no significant differences between antibiotic groups with respect to patient demographics, percentage with a severe wound, and mean days of i.v. therapy. Compared with piperacillin-tazobactam, patients treated with ertapenem received significantly fewer mean doses (25.5 versus 7.5; p < 0.0001) and lower antibiotic-related costs ($502.76 versus $355.55, respectively; p < 0.001). The $147.21 difference between groups accounts for approximately 3% of total hospital Medicare reimbursements for these infections. CONCLUSION: A CMA of treatment of diabetic foot infections showed that, compared with piperacillin-tazobactam given four times daily i.v., ertapenem given once daily i.v. was associated with lower drug acquisition and supply costs and less time and labor devoted to preparation and administration of i.v. therapy.