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N Doherty

Publications and source records attributed to N Doherty.

At least 19 recordsLinked to original sources
PubMed2001

Assessing the economic return of specializing in orthodontics or oral and maxillofacial surgery.

BACKGROUND: The authors determined the economic returns from an educational investment in the specialties of orthodontics and oral an maxillofacial surgery. They also addressed problems found in previous studies. METHODS: The marginal return for specializing in orthodontics or oral and maxillofacial surgery was determined using net present value and internal rate of return, or IRR, with the income of the general dentist serving as the common opportunity cost. Extreme scenario, threshold and one-way sensitivity analyses were used to account for variation in the data. RESULTS: The median group of orthodontists broke even 5.9 years after specialty training and had a working lifetime net return of $271,536 above that of general dentists; the IRR for them was 10.36 percent. The median group of oral and maxillofacial surgeons broke even 2.3 years after training and had a working lifetime net return of $587,563 above that of general dentists; the IRR for them was 25.30 percent. CONCLUSIONS: Under the most likely conditions, the authors found a positive economic return to dentists in both specialties from their additional dental training. PRACTICE IMPLICATIONS: The positive financial returns brought by specialization indicate that the demand for additional dental education should continue within an environment of increased educational investment costs.

Education, Dental, Graduate↗
PubMed2000

Genetic diversity of the tet(M) gene in tetracycline-resistant clonal lineages of Streptococcus pneumoniae.

The aim of the present study was to examine the stability and evolution of tet(M)-mediated resistance to tetracyclines among members of different clonal lineages of Streptococcus pneumoniae. Thirty-two tetracycline-resistant isolates representing three national (Spanish serotype 14, Spanish serotype 15, and Polish serotype 23F) and one international (Spanish serotype 23F) multidrug-resistant epidemic clones were all found to be tet(M) positive and tet(O), tet(K), and tet(L) negative. These isolates all carried the integrase gene, int, which is associated with the Tn1545-Tn916 family of conjugative transposons. High-resolution restriction analysis of tet(M) products identified six alleles, tet(M)1 to tet(M)6: tet(M)1 to tet(M)3 and tet(M)5 in isolates of the Spanish serotype 14 clone, tet(M)4 in both the Spanish serotype 15 and 23F clones, and tet(M)6, the most divergent allele, in the Polish 23F clone. This indicates that tet(M) variation can occur at the inter- and intraclone levels in pneumococci. Two alleles of int were identified, with int1 being found in all isolates apart from members of the international Spanish 23F clone, which carried int2. Susceptibility to tetracycline, doxycycline, and minocycline was evaluated for all isolates with or without preincubation in the presence of subinhibitory concentrations of tetracyclines. Resistance to tetracyclines was found to be inducible in isolates of all clones; however, the strongest induction was observed in the Spanish serotype 15 and 23F clones carrying tet(M)4. Tetracycline was found to be the strongest inducer of resistance, and minocycline was found to be the weakest inducer of resistance.

Bacterial Proteins↗
PubMed1999

Phase I trial of the hypoxic cell cytotoxin tirapazamine with concurrent radiation therapy in the treatment of refractory solid tumors.

PURPOSE: Patients with refractory solid tumors were treated with the combination of fractionated radiation therapy and multiple-dose intravenous tirapazamine to determine the toxicities and maximum tolerated dose of tirapazamine when given concurrently with radiation therapy. METHODS: Patients received radiation therapy in accordance with standard treatment practice in relation to fraction size and number of fractions for their particular cancer. In all cases, the course of radiation therapy exceeded the time of tirapazamine administration. Initially, tirapazamine was administered 5 days per week for 2 weeks for a total of 10 doses. After the first 8 patients, the schedule was changed to 3 times per week (Monday, Wednesday, Friday) for 4 weeks for a total of 12 doses. Between 3 and 6 patients were treated at each dose level. RESULTS: A total of 43 patients were treated in the study between 1991 and 1995. All patients were 18 years old or older, had a Karnofsky performance status of > or = 60% and had adequate hematologic, hepatic, and renal function. Dose escalation began at 9 mg/m(2)/dose and was increased using a modified Fibonacci schema. The maximum tolerated dose was not reached and dose escalation was stopped at 260 mg/m(2) because of other data that became available suggesting 330 mg/m(2) was associated with dose-limiting toxicity (1, 2). CONCLUSION: Tirapazamine in doses of up to 260 mg/m(2) times 12 doses can be given safely with fractionated radiation therapy. This dose appears to result in adequate plasma exposure (2) for radiation sensitization, and this schedule is being tested in a Phase II trial by the Radiation Therapy Oncology Group to determine if tirapazamine is a radiation enhancer in the clinic.

Adult↗
PubMed1995

The home health agency as a cost center.

Decisions involving the economics of home health care agencies require accurate and useful data on agency finances and cost-efficiency relationships, One step in the direction of improving economic management can be taken by defining the agency as a cost center, that is as an economic entity, with which specific resources, revenues and costs which can be expressly identified. This paper describes the economics and accounting frameworks within which resources and costs are classified and allocated into direct and indirect, and fixed and variable categories.

Accounting↗
PubMed1994

Muscle cramping in phase I clinical trials of tirapazamine (SR 4233) with and without radiation.

PURPOSE: Tirapazamine (SR 4233) is a benzotriazine di-N-oxide which acts as a hypoxic cytotoxic agent and as a radiation enhancer when given shortly before or after radiation. Three Phase I clinical trials were designed to determine the maximum tolerated dose, toxicities, pharmacokinetics, and effects on irradiated tumors and normal tissues. METHODS AND MATERIALS: Tirapazamine 9 mg/m2 to 21 mg/m2 was given i.v. 1/2 to 1 h prior to irradiation on a multiple dose schedule of 10 consecutive doses. This was later revised to a three times-per-week schedule for 12 doses. In a second clinical trial, tirapazamine was given in a single dose of 18 mg/m2 to 293 mg/m2 i.v. after irradiation. In a third trial, tirapazamine was administered without irradiation in single doses of 36 mg/m2 to 250 mg/m2, with an option for retreatment. RESULTS: Subjects reported muscle cramping of varying degrees of severity on all three dose schedules. One patient experienced Grade 3 cramping and treatment was discontinued. The most frequent site of cramping were the lower extremities. Creatine phosphokinase (CPK) values were elevated in three patients with associated muscle soreness in one patient. MB (cardiac) isoenzymes were elevated in one patient with no evidence of cardiac muscle damage, and returned to baseline at drug completion. No consistent abnormalities in clinical laboratory values were found. Stretching of the muscle was most effective in relieving the cramping. CONCLUSION: Muscle cramping has been the most frequently reported toxicity in Phase I studies of tirapazamine, though it does not appear to be dose limiting. Dose escalation on the three clinical trials continues. In vitro studies to investigate the cramping are ongoing.

Adult↗
PubMed1987

Anatomy of the junction of the vastus lateralis tendon and the patella.

Forty-one knees from adult cadavera (twenty female and twenty-one male) were dissected to study the relationship between the longitudinal axis of the patella and the angles of insertion into it of the vastus lateralis and vastus lateralis obliquus muscles. The mean and variance in the angles of insertion of the vastus lateralis obliquus tendon were found to be significantly different between men and women (p less than 0.05 and p less than 0.01, respectively). Three distinct anatomical patterns in the insertion of the vastus lateralis obliquus muscle were delineated. The vastus lateralis muscle, particularly the vastus lateralis obliquus, creates an important lateral force-vector on the patella.

Female↗
PubMed1981

The triage experiment in coordinated care for the elderly.

Triage is a model project designed to overcome the organizational and financial barriers inhibiting the provision of appropriate care to the elderly. Teams made up of a nurse clinician and a social worker performed assessment, service coordination, and monitoring functions. Services arranged by the teams were financed through a series of waivers on the use of the Medicare Trust Fund. Three hundred and seven Triage clients were followed and compared to a group of 195 elderly in a two year quasi-experimental study of functioning status outcomes, use of services, and health care costs. Triage clients had slightly better mental functioning outcomes than comparison clients; results of physical and social functioning outcomes were inconclusive. Both service utilization and costs were somewhat higher for Triage clients; the proportional difference in utilization was greater than the proportional difference in costs.

Aged↗
PubMed1981

Economic growth in the U.S. dental industry, 1950-1977.

This paper addresses the issue of economic growth in the U.S. dental industry. The rates of growth in real output in the dental industry and in the U.S. economy are compared for the period 1950-1977. The annual dental rate of 4.5 percent is significantly greater (P .001) than the 3.7 percent rate for the economy. In addition, inflation has been less in dentistry than in the economy. The consequences of growth of the dental industry are also discussed.

Dental Health Services↗
PubMed1980

Real costs of dental care in private and public practices.

The Chattanooga Project was a publicly funded program providing dental care to indigent children by private practice and public fixed and mobile clinics. Previous studies of the project have shown that the cost of providing dental care in public practices was lower than in private practices, and that this difference was not attributable either to the social characteristics of the children nor to the type of care provided. This article analyzes potential economic causes of the cost differences arising from the input-output relationships in each mode. Because the number and frequency of service types and productivity rates differed among the modes, a standard service package was developed. Productivity and costs were recalculated on the basis of this standard set of services. The results were that with services and productivity held constant the differences between private and public costs increased. The implications are that resources in the private practices were earning significantly higher returns than those in the public practices, and that public practices can offer viable economic alternatives to private practices in the provision of dental care.

Adolescent↗
PubMed1980

Triage: overcoming organizational and financial barriers to care for the elderly.

Triage is a model designed to overcome organizational and financial problems inhibiting the provision of appropriate care to the elderly. The model is being evaluated by the functioning status of the elderly, use of services, and health care costs of a group of elderly people served by Triage and one served by the conventional system. Preliminary results show, for the Triage group, improved mental functioning, less use of institutional services, and lower spending on conventional Medicare services.

Aged↗
PubMed1977

Expenditures for the dental care of indigent children in the Chattanooga project, 1971-1975.

This paper is part of a continuing study of the cost of children's dental care in a publicly funded model program. The Program--the Chattanooga Project--was designed to provide information and experience necessary for the development of similar programs elsewhere in the United States. From 1970 to 1975 comprehensive dental care was provided, at no charge, to an average of 5,500 indigent children per year. Children were treated in private practices (39%), public fixed clinics (20%), and public mobile clinics (41%). Costs were defined as public expenditures for purchasing care from private practitioners or producing care in public practices. As a framework for the analysis, program activities and their respective costs were divided into direct and indirect components. The former relate to the provision of care and the latter to noncare-oriented activities. Direct (indirect) costs per patient were $46.56 ($16.31) in private practices, $40.17 ($16.11) in fixed clinics, and $35.49 ($13.41) in mobile clinics. These results substantiate previous findings from a shorter period. A priori reasons for differences among the three modes in terms of patients' health status or the type of care provided have been specified and are currently under investigation.

Adolescent↗