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J Smith

Publications and source records attributed to J Smith.

At least 451 records · Page 25Linked to original sources
PubMed1997

Intrinsic control of vascularization in developing cartilage rudiments.

The vascularization of developing cartilage rudiments is temporally and spatially defined. By using an in vivo angiogenesis model, the chorioallantoic membrane (CAM) of the chick embryo and chick embryo cartilage rudiments, we conclude that the factors controlling the vascular invasion of cartilage rudiments are intrinsic. Intact rudiments, separate hypertrophic zones and separate rounded cell zones, when grafted onto the CAM, become vascularized in the same temporal and spatial manner as occurs in ovo. When grown as organ cultures prior to CAM grafting, rudiments still become vascularized in the same temporal and spatial manner. The integrity of the extracellular matrix and the presence of the periosteum are two physical factors regulating the control of vascularization. Removal of the periosteum from hypertrophic regions caused a cessation of the invasion. Insults to the matrix via brief enzymatic degradation of extracellular matrix components resulted in invasion and erosion of rounded cell zones at an earlier time than is ordinarily seen both in ovo and on the CAM.

Animals↗
PubMed1997

Comparison of two blood cell separators in collecting peripheral blood stem cell components.

To ensure that a sufficient number of CD34+ cells are collected for an allogeneic blood progenitor cell transplant, the most effective blood cell separator should be used to collect peripheral blood stem cell (PBSC) components. We compared the effectiveness of two blood cell separators. We gave 29 healthy people 7.5 or 10 micrograms kg-1 of granulocyte colony stimulating factor (G-CSF) daily for 5 days and collected one PBSC component with either a Fenwal CS3000 (n = 15) or a Cobe Spectra (n = 14) blood cell separator. The volume of blood processed was the same for each machine (8.4 +/- 1.0 L; range = 4.9-9.4 L for the CS3000 and 8.9 +/- 1.0 L; range 6.7-10.9 L; P = 0.71). The components collected with the CS3000 contained more mononuclear cells (39.6 +/- 21.9 x 10(9) compared with 26.9 +/- 5.6 x 10(9), P = 0.02) and fewer neutrophils (1.38 +/- 1.88 x 10(9) compared with 5.53 +/- 8.71 x 10(9), P = 0.001). The total number of CD34+ cells collected with the two instruments was the same (470 +/- 353 x 10(6) for the CS3000 and 419 +/- 351 x 10(6) for the Spectra; P = 0.64) as was the number of CD34+ cells collected per litre of whole blood processed (55.9 +/- 42.0 x 10(6) L-1 compared with 45.9 +/- 37.9 x 10(6) L-1; P = 0.59). The mononuclear cell collection efficiency was greater for the CS3000 (82.4 +/- 54.9% compared with 53.3 +/- 14.1; P = 0.04) but the CD34+ cell collection efficiencies were the same (87.4 +/- 61.1% for the CS3000 compared with 56.3 +/- 23.5% for the Spectra; P = 0.07). In conclusion, both blood cell separators collected components which contained large numbers of CD34+ cells, but those collected with the CS3000 contained fewer neutrophils and the CS3000 was more efficient at collecting mononuclear cells.

Adult↗
PubMed1997

The kinetics of G-CSF mobilization of CD34+ cells in healthy people.

When healthy people are given granulocyte colony stimulating factor (G-CSF) for 10 days the number of CD34+ cells in the peripheral blood begins to increase on the fourth day, reaches a maximum on the sixth day and then decreases. In this study, we further define the time and variability of peak mobilization of CD34+ cells. Twenty-two healthy people were given G-CSF (7.5 or 10 micrograms kg-1 day-1) subcutaneously each morning for 5 days and peripheral blood CD34+ cell counts were analysed immediately prior to the fourth (day 4) and fifth (day 5) G-CSF injection and 24 h after the fifth injection (Day 6). White blood cell (WBC) and neutrophil counts were greatest on day 6 [WBC = 43.8 +/- 13.9 x 10(9) L-1 (mean +/- 1 SD) and neutrophils = 36.6 +/- 12.8 x 10(9) L-1]. In contrast the CD34+ cell counts on day 6 (107 +/- 104 x 10(6) L-1) were less than on day 5 (128 +/- 136 x 10(6) L-1) (P = 0.048) but still greater than on day 4 (60.7 +/- 40.2 x 10(6) L-1) (P < 0.0001). The CD34+ cell counts of 10 donors were measured 2, 4 and 6 h after the fifth injection to determine if the counts increased further between days 5 and 6. The number of CD34+ cells in the blood on day 5 2 h after the fifth injection (193 +/- 277 x 10(6) L-1) was greater than the number prior to the injection (158 +/- 190 x 10(6) L-1), 4 h post-injection (139 +/- 158 x 10(6) L-1) and 6 h post-injection (170 +/- 236 x 10(6) L-1), but the differences were not significant (P = 0.29, 0.25 and 0.45). The number of CD34+ cells in the blood of 12 people were measured before and after the fourth G-CSF dose. Prior to the day 4 injection the CD34+ count was 61 +/- 40 x 10(6) L-1. At 2, 4 and 6 h the counts were 60 +/- 40, 61 +/- 29 and 64 +/- 30 x 10(6) L-1, respectively, and the differences were not significant (P = 0.99, P = 0.98, and P = 0.73). In conclusion, when healthy volunteers are given daily G-CSF injections, the number of mobilized CD34+ cells was the greatest on day 5, slightly less on day 6 and the least on day 4. If only one PBSC component is needed, PBSCs can be collected on day 5 after only 4 days of G-CSF. If PBSC components are collected on both days 5 and 6, the fifth dose can be given either before or after the collection of the first PBSC component.

Adult↗
PubMed1997

Blood counts in healthy donors 1 year after the collection of granulocyte-colony-stimulating factor-mobilized progenitor cells and the results of a second mobilization and collection.

BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF)-mobilized blood cells are being used for allogeneic transplants, but the long-term effects of G-CSF on healthy individuals are not known. Furthermore, it is not certain how many CD34+ cells can be collected in a second mobilization and collection procedure. STUDY DESIGN AND METHODS: Nineteen people were given 2, 5, 7.5, or 10 micrograms of G-CSF per kg per day for 5 days, and blood progenitor cells were collected by apheresis on the sixth day; this was done on two occasions separated by at least 12 months. Blood counts obtained before and after each course of G-CSF and the quantity of cells collected were compared. RESULTS: There were no differences in white cell (WBC), platelet, red cell, and WBC differential counts measured before each course of G-CSF, and all the values were in the normal range. In a subset of 12 people who received 7.5 or 10 micrograms of G-CSF per kg per day for both courses, the numbers of neutrophils, mononuclear cells, and CD34+ cells in the blood after each course were similar (34.1 +/- 7.31 x 10(9)/L vs. 36.4 +/- 12.3 x 10(9)/L, p = 0.24; 6.59 +/- 2.28 x 10(9)/L vs. 5.63 +/- 2.11 x 10(9)/L, p = 0.24; and 92.0 +/- 55.6 x 10(5)/L vs. 119.2 +/- 104.6 x 10(6)/L; p = 0.48, respectively), as were the quantities of mononuclear cells (31.0 +/- 8.4 x 10(9) vs. 31.0 +/- 6.1 x 10(9); p = 0.64) and CD34+ cells (417 +/- 353 x 10(6) vs. 449 +/- 286 x 10(6); p = 0.53) collected in the two apheresis procedures. Furthermore, there was a positive correlation between the quantity of CD34+ cells collected from each of the 12 people per liter of whole blood processed in the two procedures (r2 = 0.86, p < 0.001). CONCLUSION: One year after the administration of G-CSF to healthy people, their blood counts were normal and unchanged from pretreatment counts. If healthy people donate blood progenitor cells after a second G-CSF course the quantity of CD34+ cells collected will be similar to that obtained in the first collection.

Adult↗
PubMed1997

Composition of peripheral blood progenitor cell components collected from healthy donors.

BACKGROUND: Peripheral blood progenitor cell (PBPC) components are being collected from healthy donors for allogeneic transplantation, but the quantity, quality, composition, and variability of PBPCs collected from healthy people given granulocyte-colony-stimulating factor (G-CSF) have not been evaluated. STUDY DESIGN AND METHODS: PBPC components were collected from 150 healthy people who were given G-CSF (5, 7.5, or 10 microg/kg/day) for 5 days. The components were evaluated for white cell (WBC), mononuclear cell, CD34+ cell, neutrophil, platelet, and red cell (RBC) composition. RESULTS: The quantities collected were: WBCs, 35.0 +/- 16.4 x 10(9) (range, 11.9-163.3 x 10(9)); mononuclear cells, 33.3 +/- 14.4 x 10(9) (range, 11.9-139.6 x 10(9)); CD34+ cells, 412 +/- 287 x 10(6) (range, 70-1658 x 10(6)); neutrophils, 1.71 +/- 3.59 x 10(9) (range, 0-27.6 x 10(9)); RBCs, 7.2 +/- 4.0 mL (range, 0-22.1 mL); and platelets, 480 +/- 110 x 10(9) (range, 250-920 x 10(9)). PBPC components collected from people given G-CSF at 7.5 or 10 microg per kg per day contained significantly more CD34+ cells (respectively, 428 +/- 300 x 10(6); range, 70-1658 x 10(6) and 452 +/- 294 x 10(6); range, 78-1380 x 10(6)) than those from people given G-CSF at 5 microg per kg per day (276 +/- 186 x 10(6); range, 91-767 x 10(6)) (p = 0.007 and p = 0.002). When 10 microg per kg per day of G-CSF was given, 50 percent of the components contained enough CD34+ cells for transplantation to a 75-kg recipient (375 x 10(6) CD34+ cells), but 10.6 percent of the components contained less than 150 x 10(6) CD34+ cells and thus would provide a transplantable dose only for a 30-kg patient. CONCLUSION: One PBPC component collected from a healthy donor given 7.5 or 10 microg per kg per day of G-CSF should contain 70 to 1660 x 10(6) CD34+ cells, with 0 to 22 mL of RBCs. Because of the great variability in the number of CD34+ cells collected, the quantity of CD34+ cells in each component should be measured after each procedure to ensure that sufficient quantities of cells are present for a successful transplant.

Antigens, CD34↗
PubMed1997

Corporate information systems in health organisations.

This paper presents an overview of the nature of corporate information systems and their applications in health organisations. It emphasises the importance of financial and human resource information in the creation of a corporate data model. The paper summarises the main features of finance and human resource systems as they are used in health organisations. It looks at a series of case studies carried out in health organisations, which were selected on the basis of their representation of different aspects of service delivery. It also discusses the theoretical and practical perspectives of the systems themselves, their roles in information management, executive and decision support, and in planning and forecasting.

Australia↗
PubMed1997

Rapid geographic spread of a methicillin-resistant Staphylococcus aureus strain.

In May 1993, an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) was identified at our tertiary care teaching center. The epidemic MRSA strain was transmitted efficiently in the hospital environment. Subsequent investigations indicated that the strain had been introduced into western Canada by a patient who had recently been hospitalized for 3 months in the Punjab, India, and had been admitted to a hospital in rural British Columbia shortly after his arrival in Canada. Transfer of the patient to a hospital in Vancouver and subsequent transfer of a colonized patient contact to a hospital in Winnipeg, Manitoba, resulted in major outbreaks of MRSA at these two large tertiary care centers within 6 weeks of the arrival of the index case in Canada. Epidemiological typing of the S. aureus coagulase gene with use of a polymerase chain reaction method and pulsed-field gel electrophoresis documented clonality of this strain. These outbreaks again illustrate both the propensity of certain strains of S. aureus to produce epidemic disease, including rapid spread within the institutional setting, and the global nature of problems with antimicrobial resistance.

Bacterial Typing Techniques↗
PubMed1997

Prior knowledge and reading comprehension ability of deaf adolescents.

Fifty-one severely to profoundly deaf students (mean dB hearing loss = 89) were randomly assigned to two groups that differed by the type of probes (short or long) used to elicit prior knowledge (PK). PK scores were used to predict reading comprehension (RC), which was assessed by students' responses to three types of questions: test-explicit (TE), text-implicit (TI), and script-implicit (SI). Multiple regression models with PK scores and scores from a standardized achievement test (Stanford Achievement Test - Hearing Impaired Version, reading subtest) were also used to predict RC. The regression model showed that, for the group pretested with an in-depth, or long, probe of PK, the best predictor of RC was the ability to answer TE and SI questions. We present discussions of the observed differences in comprehension as a function of long and short knowledge probes and the use of three question types, together with implications for instruction.

Journal Article↗
PubMed1997

A survey of multicultural awareness among hospital and clinic staff.

Building a knowledgebase regarding multicultural beliefs and practices will help health care providers meet the challenge of caring for persons of diverse cultures. It is evident that developing greater multicultural awareness will also help health care workers improve patient care. For this reason, an Interdisciplinary Multicultural Patient Care Team (IMPACT) was developed at the University of Wisconsin Hospital and Clinics (UWHC) and UW Children's Hospital in 1994. The IMPACT sought funds through the University of Wisconsin-Milwaukee Institute on Race and Ethnicity to conduct a hospital- and clinic-wide survey of its 4,000 full- and part-time employees regarding their understanding of multicultural issues. The goal of the survey was to expand upon the pilot study conducted in 1994 with the intent of ascertaining staff cultural awareness and educational needs. Over 800 multidisciplinary personnel returned the survey for a 21 percent response rate. These data will be used to set up educational programs and develop a resource network for all personnel.

Cultural Diversity↗
PubMed1997

Rejecting conventional wisdom: how academic medical centers can regain their leadership positions.

Academic medical centers (i.e., medical schools and their principal hospitals) are following very similar strategies in attempts to secure their futures. It is likely that these undifferentiated strategies will fail, since most of them have been copied from the lower-cost, geographically better-positioned hospitals and health systems. Despite a wealth of innovative, entrepreneurial talent and the potential to reshape the world that AMCs live in, most AMCs are in reactive modes. Future directions and strategies are almost always shaped, forced, and justified by external pressures. The major problem with the strategic plans of most AMCs is that they are based on conventional industry wisdom. Strategic plans tend not to be analytically driven. The insight and understanding of those factors that drive the demand for AMCs' services and determine the performances of AMCs are lacking. The authors note some questions that are critical to the formulation of strategies for AMCs. For example, how can the research mission be changed from a cost-based to a value-based endeavor? Most AMCs cannot answer these questions, and if they do address them in the planning process, they do so superficially. Several examples of the factors that need to be understood are also given, such as patients' purposes and needs in seeking specialty care. Alternative strategies are listed, such as maintaining and exploiting the economic irrationality of the market rather than acting as if it were economically rational or forcing it to become so. Last, the authors outline the scope of the changes that are required and urge AMCs to reject conventional wisdom, determine their own unique situations, and work from there.

Academic Medical Centers↗
PubMed1997

Child adjustment in high conflict families.

Children exposed to spousal violence are at risk for social-emotional problems. This research investigated a number of family and child factors which might influence the effects of witnessing spousal violence on young children. Fifty-four mothers who had at least one child in the age range of 3 to 6 years participated in the study. These women had left a violent relationship 12 to 24 months prior to their participation in the study and were not in a new relationship. Information was collected through a structured interview which included the administration of a standardized family violence measure (conflict tactics scale) and child adjustment profile (child behaviour checklist). Forty-two per cent of the children exhibited a level of behavioural problems which would warrant clinical intervention. The amount of violence that the children witnessed, the children's responses when the violence occurred and whether the child copied the violent partner's behaviour, were associated with the children's behavioural adjustment scores. Maternal parenting style was not found to have a significant effect on behavioural adjustment. The study provided important quantitative and qualitative data on the nature of parent-child relationships and children's adjustment in families where there is spousal violence.

Adaptation, Psychological↗
PubMed1997

A comparative study of polyacrylic acid (Viscotears) liquid gel versus polyvinylalcohol in the treatment of dry eyes.

We conducted a prospective, randomised, single-masked study comparing the safety and efficacy of polyacrylic acid 0.2% (PAA) and polyvinylalcohol 1.4% (PVA) in 85 patients (PAA 43, PVA 42) with dry eyes. The two groups were similar in patient demographics and study parameters at baseline. With treatment, the reduction in total symptoms (gritty or foreign body sensation, burning sensation, dry eye sensation, photophobia, others) and signs (conjunctival hyperaemia, ciliary injection, corneal and conjunctival epithelial staining) score on PAA was significantly greater than that on PVA at both two and four weeks. The daily frequency of instillation of PAA was significantly less than that of PVA on 16 of the 27 (59%) study days. For overall local tolerance there was a significant preference for PAA compared to PVA by both patients and doctors. Only one patient on each treatment had an adverse event and neither was serious. PAA (Viscotears) was as safe as, but better tolerated and more effective than PVA in the treatment of dry eye conditions.

Acrylic Resins↗
PubMed1997

Stable azole drug resistance associated with a substrain of Candida albicans from an HIV-infected patient.

Oral candidiasis is one of the earliest and most frequent complications of a failing immune system in HIV-infected individuals. For several years, oral candidiasis has been treated effectively with azole drugs, the one most frequently used is fluconazole. Unfortunately, extensive use of the drug for treatment and prophylaxis has led to treatment failure in an increasing number of patients. In most of these cases, strains of C. albicans isolated from the infection are less susceptible to fluconazole. The development of azole resistance in strains of C. albicans has been studied biochemically and more recently with molecular techniques. One excellent example of the development of azole resistance in C. albicans has been documented in a series of 17 C. albicans isolates from a single patient over a 2-year period. During this time, the patient experienced 14 episodes of oral candidiasis and was treated with increasing doses of fluconazole. Molecular and biochemical analyses confirms that the isolates are the same strain of C. albicans and that the resistance in these isolates is stable over 600 generations, suggesting that the changes in this strain are genetic in nature. In addition, the development of resistance is correlated with the identification of a substrain or variant of the original strain, as identified by restriction fragment length polymorphism (RFLP) analysis with the moderately repetitive probe, Ca3. The analysis of this series of isolates demonstrates that azole drug resistance is associated with several small genetic changes, each of which contributes to the overall resistance of the strain. Clearly, continual use of azole drugs by a patient can select for genetic changes that render oral candidiasis refractory to treatment.

AIDS-Related Opportunistic Infections↗
PubMed1997

Multiple-dose pharmacokinetics of ritonavir in human immunodeficiency virus-infected subjects.

The multiple-dose pharmacokinetics of ritonavir were investigated in four groups of human immunodeficiency virus-positive male subjects (with 16 subjects per group) under nonfasting conditions; a 3:1 ritonavir:placebo ratio was used. Ritonavir was given at 200 (group I), 300 (group II), 400 (group III), or 500 (group IV) mg every 12 h for 2 weeks. The multiple-dose pharmacokinetics of ritonavir were moderately dose dependent, with the clearance for group IV (6.8 +/- 2.7 liters/h) being an average of 32% lower than that for group I (10.0 +/- 3.2 liters/h). First-pass metabolism should be minimal for ritonavir. The functional half-life, estimated from peak and trough concentrations, were similar among the dosage groups, averaging 3.1 and 5.7 h after the morning and evening doses, respectively. The area under the concentration-time curve at 24 h (AUC24) and apparent terminal-phase elimination rate constant remained relatively time invariant, but predose concentrations decreased 30 to 70% over time. Concentration-dependent autoinduction is the most likely mechanism for the time-dependent pharmacokinetics. The Km and initial maximum rate of metabolism (Vmax) values estimated from population pharmacokinetic modeling (nonlinear mixed-effects models) were 3.43 microg/ml and 46.9 mg/h, respectively. The group IV Vmax increased to 68 mg/h after 2 weeks. The maximum concentration of ritonavir in serum (Cmax) and AUC after the evening doses were an average of 30 to 40% lower than the values after the morning doses, while the concentration at 12 h was an average of 32% lower than the predose concentration, probably due to protracted absorption. Less than 2% of the dose was eliminated unchanged in the urine. Triglyceride levels increased from the levels at the baseline, and the levels were correlated with baseline triglyceride levels and AUC, Cmax, or predose concentrations.

Adult↗