Search PubMed⌕ Search

Biomedical subjects

J Smith

Publications and source records attributed to J Smith.

At least 505 records · Page 28Linked to original sources

Differential expression of macrophage inflammatory protein-2 and monocyte chemoattractant protein-1 in experimental glomerulonephritis.

We examined the relation between glomerular expression of chemokines from alpha-subfamily (macrophage inflammatory protein-2, MIP-2) and beta-subfamily (monocyte chemoattractant protein-1, MCP-1) and infiltration of neutrophils and monocytes in antibody mediated glomerulonephritis in rats. In the accelerated model of nephrotoxic nephritis (NTN), glomerular expression of MIP-2 and MCP-1 genes correlated with the sequential migration of neutrophil and monocyte influx, respectively. These relationships were investigated further in the heterologous phase of NTN by applying various treatments known to modulate the severity of injury. Pretreatment with bacterial lipopolysaccharide resulted in greater injury, MIP-2 expression increased 25- to 50-fold, and the glomerular neutrophil count increased two- to fourfold. Both MIP-2 mRNA levels and neutrophil infiltration were reduced by additional pretreatment with IL-6, IL-1 receptor antagonist, soluble IL-1 receptor or soluble TNF receptor (Spearman correlation coefficient r = 0.897, P < 0.005). In the heterologous phase of NTN, different pre-treatments only resulted in trivial changes in MCP-1 expression and monocyte infiltration. In conclusion, glomerular MIP-2 gene expression correlates with neutrophil infiltration both temporally during the evolution of nephritis, and when glomerular injury is modified by treatment. Glomerular MCP-1 gene expression correlates with monocyte influx. The data show chemokines of alpha- and beta-subfamilies co-operative to cause selective and sequential migration of different leukocyte subsets during development of antibody mediated glomerulonephritis.

Animals↗

Consonant-vowel interdependencies in babbling and early words: preliminary examination of a locus equation approach.

Consonant-vowel productions at two distinct stages of language development were studied in a single female child. At 12 months canonical babbling syllables (N = 144) identified by a panel of listeners as comprising [bV], [dV], and [gv] tokens were acoustically analyzed by measuring F2 transition onset and F2 midvowel frequencies and plotting their relationship as locus equations for each stop category. A regression analysis performed on these scatterplots revealed differential slopes and y-intercepts as a function of stop place. The same analysis was performed 9 months later on CV utterances (N = 243) produced as syllable-initial segments of real words by the same child. Whereas labial and velar locus equation parameters moved toward more adult-like values, alveolar slope and y-intercept moved away from adult values and more in the direction of decreased coarticulation between vowel and consonant. There was greater scatter of data points around the regression line for production of words compared to babbling. These results are compared to locus equations obtained from 3-5-year-olds and adults. Locus equations appear to be useful as an empirical developmental probe to document how CV productions gradually approach adult categorical standards.

Cross-Sectional Studies↗

Changes in blood counts after the administration of granulocyte-colony-stimulating factor and the collection of peripheral blood stem cells from healthy donors.

BACKGROUND: After the collection of granulocyte-colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells from healthy donors, the donor platelet counts fall. However, the magnitude and duration of this decrease are not known. STUDY DESIGN AND METHODS: Sixty healthy people were given G-CSF (5, 7.5, or 10 micrograms/kg/day) for 5 days (Days 1-5), and 1 peripheral blood stem cell component was collected on Day 6. The platelet count, white cell count, absolute neutrophil count, hematocrit, and red cell count were measured before administration of G-CSF (Day 0), before collection of peripheral blood stem cells on Day 6, and on Days 8, 10, 13, 16, and 20. RESULTS: The platelet count fell from 261 +/- 47 x 10(9) cells per L on Day 0 to 159 +/- 30 x 10(9) cells per L on Day 8 (p < 0.0001) and reached its lowest level on Day 10 (146 +/- 30 x 10(9)/L; p < 0.001). Compared to Day 0 levels, the platelet count was lower on Day 13 (185 +/- 49 x 10(9)/L, p < 0.001), was the same on Day 16 (270 +/- 53 x 10(9)/L), and was greater on Day 20 (333 +/- 60 x 10(9)/L, p < 0.0001). The white cell count returned to pretreatment values on Day 13, and the absolute neutrophil count returned to pretreatment values on Day 10 (Day 0 white cell count = 6.05 +/- 1.59 x 10(9)/L and Day 0 absolute neutrophil count = 3.97 +/- 1.52 x 10(9)/L). On Day 20, both were less than pretreatment values (white cell count = 5.14 +/- 1.24 x 10(9)/L, p = 0.0007 and absolute neutrophil count = 3.20 +/- 1.24 x 10(9)/L, p = 0.0036). The red cell counts on Day 16 (4.52 +/- 0.41 x 10(12)/L) and Day 20 (4.42 +/- 0.39 x 10(12)/L) were less than Day 0 values (4.73 +/- 0.43 x 10(12)/L, p = 0.008 and p < 0.0001, respectively). The hematocrit on Day 20 (39.2 +/- 3.2%) was also less than that on Day 0 (41.2 +/- 4.8%; p = 0.01). The changes in these blood counts were not affected by the dose of the G-CSF. CONCLUSION: After stimulation with granulocyte-colony-stimulating factor and the collection or peripheral blood stem cells, the platelet counts in normal donors were decreased for at least 7 days (Days 6-13). Two weeks after collection of peripheral blood stem cells (Day 20), platelet production was increased, but the production of neutrophils and red cells was decreased. If two or more peripheral blood stem cell components are collected, then the platelet count should be measured after the second and subsequent collections. Further studies on the long-term effect of G-CSF on blood counts are needed.

Adult↗

Treatment of normal individuals with granulocyte-colony-stimulating factor: donor experiences and the effects on peripheral blood CD34+ cell counts and on the collection of peripheral blood stem cells.

BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) has been used in patients to increase the level of circulating hematopoietic progenitors. Although G-CSF has been administered to some healthy individuals, the kinetics of mobilization of peripheral blood stem cells (PBSCs), the optimum dose schedule and the incidence and nature of adverse reactions in normal individuals are not completely defined. STUDY DESIGN AND METHODS: Normal individuals (n = 102) who received G-CSF for 5 or 10 days at doses of 2, 5, 7.5, or 10 micrograms per kg per day were studied. The subjects were observed for symptoms and physical changes, and blood samples were obtained for a variety of laboratory tests. After 5 or 10 days of G-CSF treatment, PBSCs were collected by apheresis and analyzed. RESULTS: Overall, 89 percent of the individuals completed the 5-day treatment protocol and 88 percent completed the 10-day protocol without modification of the dose of G-CSF administered. Ninety percent of donors experienced some side effect of G-CSF. The most frequent effects noted were bone pain (83%), headache (39%), body aches (23%), fatigue (14%), and nausea and/or vomiting (12%). The dose of G-CSF administered directly affected the proportion of people with bone pain (p = 0.025) or body aches (p = 0.045) or who were feeling hot or having night sweats (p = 0.02) or taking analgesics (p = 0.01). With the 5-day dose schedule, several changes in serum chemistries occurred, including increases in alkaline phosphatase (p = 0.001), alanine aminotransferase (p = 0.0013), lactate dehydrogenase (p = 0.0001), and sodium (p = 0.0001). Decreases occurred in glucose (p = 0.045), potassium (p = 0.0004), bilirubin (p = 0.001), and blood urea nitrogen (p = 0.0017). In donors who received G-CSF for 5 days, the absolute neutrophil count was increased after one G-CSF dose, and it reached a maximum on Day 6, as did the number of CD34+ cells (64.6 +/- 55.9 x 10(6) cells/L). In those same donors, the platelet count after apheresis on Day 6 was 32 +/- 13 percent lower than pretreatment values (250 +/- 42 x 10(9) cells/L). In donors receiving G-CSF for 10 days, the neutrophil count reached a maximum on Day 8, but the number of CD34+ cells peaked on Day 6 (58.3 +/- 52.1 x 10(5) cells/L) and then declined. The platelet count decreased from pretreatment values by 28 +/- 12 percent prior to apheresis on Day 11. When individuals were treated for 5 days with G-CSF, the quantity of CD34+ cells collected was directly related to the G-CSF dose. When 5 micrograms per kg per day was given, 2.80 +/- 1.81 x 10(8) cells were collected, compared with collection of 4.67 +/- 3.11 x 10(8) cells when 10 micrograms per kg per day was given (p = 0.04). More important, PBSCs collected after 10 days of G-CSF administration (5 micrograms/kg/day) had significantly fewer CD34+ cells (0.82 +/- 0.37 x 10(8) cells, p = 0.01) than did PBSCs collected after 5 days of G-CSF (5 micrograms/kg/day). CONCLUSION: Most normal donors receiving G-CSF experience side effects, but these are mild to moderate in degree. Some alterations in blood chemistries occur, but none were clinically serious. Because of the symptoms associated with G-CSF, these individuals must be monitored closely. The treatment of normal donors with G-CSF for more than 5 days significantly decreased the number of circulating CD34+ cells and the quantity collected by apheresis.

Adult↗

A simple and rapid competitive enzyme-linked immunosorbent assay to identify HPA-1a (PlA1)-negative donor platelet units.

BACKGROUND: Alloantibodies to HPA-1a (PlA1) are the major cause of neonatal alloimmune thrombocytopenia and posttransfusion purpura and have been implicated in refractoriness to random-donor platelet transfusions. However, most assays used to phenotype platelets are cumbersome or time-consuming for large numbers of samples. STUDY DESIGN AND METHODS: A simple, competitive (inhibition) enzyme-linked immunosorbent assay for HPA-1a phenotyping of donor platelets was developed. A segment from the donor platelet unit transfer line was sealed to obtain a small aliquot of platelets. These platelets were washed once and added to a predetermined dilution of serum containing alloantibodies to HPA-1a. Residual anti-HPA-1a binding to the glycoprotein IIb/IIIa purified by lectin and high-performance liquid chromatography and coated on microtiter wells was detected with a conjugated antihuman IgG. A lack of inhibition equivalent to control (no platelets) was used to determine that the platelets were HPA-1b/b. RESULTS: Of the 557 platelet units tested, 14 (2.5%) were found to be HPA-1a negative, and they were confirmed to be HPA-1b/b by DNA genotyping. Two of the 14 HPA-1b/b units were also HPA-3b/b (approx. 0.35% of the random population). Use of the microtiter format allows 100 to 200 samples to be processed per day. CONCLUSION: This simple and inexpensive assay is useful for identifying HPA-1b/b units for platelet-compatible transfusions or for platelet antibody investigations.

Antigens, Human Platelet↗

A survey of heparin monitoring in Australasia.

Full dose heparin therapy is monitored by a variety of laboratory methods, of which the activated partial thromboplastin time (APTT) is the most popular. A large number of APTT reagents are currently available, with different sensitivities to heparin evident in many. Within the literature it is apparent that there is a lack of consensus, and indeed some confusion, regarding the therapeutic ranges for the APTT for standard heparin therapy in the treatment of venous thromboembolic disease. Accordingly we conducted an Australasian survey to evaluate current laboratory and clinical practices in monitoring heparin therapy, to determine the extent of variation in the approach and to stimulate the process of standardisation of acceptable procedures and methodology. Results of the survey demonstrate that currently there is no uniform practice used to establish therapeutic ranges for monitoring standard heparin therapy. Furthermore, results suggest that current practice may lead to subtherapeutic anticoagulation in many laboratories.

Australia↗

Maternal factors contributing to asphyxia neonatorum.

The objective was to identify maternal risk factors for birth asphyxia, and took the form of a retrospective study over 3 years of 15,964 deliveries. The antenatal and intrapartum course of 68 mothers who delivered babies with birth asphyxia was studied. Babies < 34 weeks/< or = 2000 g at birth were excluded. A 5-min Apgar score < 6 was regarded as abnormal. The incidence of asphyxia neonatorum was 4.6/1000. Most mothers (76 per cent), resided locally, booked (91 per cent), and had satisfactory antenatal clinic attendance (average seven visits). The distribution showed a disproportionately large number of grand multiparas (10 per cent). Labour was characterized by prolonged first (49 per cent) and second (36 per cent) stages with a high incidence of meconium in the amniotic fluid (47 per cent). Most deliveries (53 per cent) were by caesarian section of which 44 per cent were performed for fetal distress. Meconium aspiration was common (34 per cent). High risk signs in labour can be recognized. The judicious use of the partogram, fetal scalp blood pH, and amino-infusion are encouraged.

Asphyxia Neonatorum↗

Neutropenia is associated with bacteremia in patients infected with the human immunodeficiency virus.

Neutropenia occurs in approximately 17% of symptomatic patients infected with HIV. Results of studies have failed to demonstrate a consistent relationship between HIV-related neutropenia and the subsequent development of bacterial infections. This was a case control study to determine if HIV-related neutropenia was associated with increased rates of bacteremia. The experimental group was comprised of 29 patients infected with HIV that had an absolute neutrophil count less than 1000 cells/mm3 and were paired with 29 control subjects infected with HIV that had been matched for age, sex, CD4 count, and month and year of entry. The frequency of bacteremia was 12.6 per 100 patient months among the experimental group compared to a frequency of 0.87 per 100 patient months among the control group (relative risk [RR] = 14.9, P = 0.0027). Other independent risks for the development of bacteremia included central venous catheters (RR = 3.9, P = 0.03), with a trend toward increased risk for bacteremia in those patients who were intravenous drug users (RR = 3.8, P = 0.11), or who had infiltrative bone marrow disease (RR = 3.1, P = 0.11). Multivariate analysis demonstrated that neutropenia (odds ratio [OR] = 22.6, P = 0.028) and the presence of a central venous catheter (OR = 8.5, P = 0.026) were significant risks for bacteremia. These data suggest that neutropenia is a significant risk for the development of bacteremia in patients infected with HIV.

Analysis of Variance↗

Langerhans cell (eosinophilic) granulomatosis. A clinicopathologic study encompassing 50 years.

We summarize our experience with 238 cases of Langerhans cell granulomatosis (LCG), 198 of whom were followed for a median period of 10.5 years. Our patients did well unless overtreated, and no deaths were attributed to the disorder itself. The disease may appear in unifocal or multifocal form, and treatment is based on this fact. Virtually all patients recovered completely except for occasional residual orthopedic problems or residual diabetes insipidus. Several of the patients underwent subsequent pregnancies without difficulty. The granulomas primarily occur in bone, but lung, skin, and lymph nodal involvement is not uncommon. Involvement of thyroid, thymus, and other sites is rare. The hallmark of the disease is the accumulation of Langerhans cells (LCs). We review the pathology of LCG by histology, electron microscopy, and immunolabeling. LCs originally were identified in squamous epithelium, but these cells are part of the widespread system of dendritic cells. The latter cells, which arise from CD34+ progenitors, are specialized and efficient antigen-presenting cells for T-cell-mediated immunity. In LCG, however, the major associated cells are not T cells, but mature eosinophils: hence the original name eosinophilic granuloma. Confusion about terminology has been based upon the scanty and rather crude pathology reports in the original literature. The term histiocytosis X was meant to cover a spectrum of three diseases--eosinophilic granuloma, Hand-Schüller-Christian disease (HSC), and Letterer-Siwe disease (LS)--but HSC and LS have no basis in pathology and hence the terms are meaningless. The term HSC has become a synonym for multifocal eosinophilic granuloma (LCG). The term LS has been used in reporting a number of benign, malignant, or unknown conditions. We prefer the term LCG to avoid confusion with the term histiocytosis X because there is evidence that the LC is not a member of the mononuclear phagocyte system and hence not a tissue macrophage, and because the use of the term "histiocyte" has become a convenience in much of the literature when reporting incompletely understood diseases.

Adolescent↗

A patient care team approach to multicultural patient care issues.

As the demographics of the United States continue to change to include more foreign nationals, nursing professionals will need to become increasingly aware of multicultural issues. Developing a greater cultural awareness of a particular client population can aid health care providers in improved caregiving. An interdisciplinary multicultural patient care team (IMPCT) was formed to enlarge the scope of nursing practice by educating nurses and other support staff about culturally diverse groups. The purpose of the IMPCT was to promote high-quality care to culturally diverse patients and their families. An IMPCT led by an advanced practice nurse would assist nursing staff in developing cultural awareness and sensitivity and would enhance nurses' ability to provide a holistic approach to nursing care.

Education, Nursing, Continuing↗

Recruiting and retaining volunteer community preceptors.

As more medical schools are providing primary care experiences for their students, competition among schools to recruit and retain volunteer community preceptors is increasing dramatically. The University of Illinois College of Medicine at Chicago competes for preceptors with six other major medical schools in the metropolitan area. Its Longitudinal Primary Care (LPC) Program is one of the largest programs of its kind in the country, with 320 preceptors at approximately 250 sites in metropolitan Chicago. By studying the literature, carefully reviewing their pilot program, and surveying preceptors about their motivations and needs, the authors have created a successful model for increasing and maintaining a pool of preceptors. This paper describes the development of this model and the specific methods used to recruit new preceptors (e.g., using a recruitment brochure), and to retain and reward preceptors (e.g., offering adjunct faculty positions, faculty development programs, etc.).

Academic Medical Centers↗

Use of bone morphogenetic protein-2 in the rabbit ulnar nonunion model.

The ability of the osteoinductive protein and recombinant human bone morphogenetic protein-2, combined with polylactic glycolic acid porous microspheres and autologous blood clot to heal a large segmental defect was tested in a rabbit diaphyseal defect model. Two centimeter nonuniting defects were surgically created in the bilateral ulnae of 50 male New Zealand white rabbits. Each defect was then implanted with a pastelike polylactic glycolic acid/blood clot combination that was mixed with 5 different concentrations of recombinant human bone morphogenetic protein-2. The forearms were radiographically assessed on a biweekly schedule for 8 weeks. At 8 weeks, all animals were sacrificed and forearms radiographed. Radiographs were then scored by 3 independent observers for bone formation and union rates. United limbs were tested in torsion for mechanical strength using a Burstein torsion tester. All nonunited limbs were analyzed histologically as were 2 united limbs from each dosage group. Radiographic evaluation revealed that there was a dose dependent response in healing of the ulnar defect with a higher bone formation rate in the 2 higher dose limbs than in the lower dose limbs. Union was achieved in 100% of the highest dose limbs, whereas only 50% of the lowest dose limbs achieved bony union. No defects implanted with carrier alone achieved union. Biomechanical studies revealed significantly stiffer bone than age matched controls. Histologic analysis demonstrated normal bone formation with abundant normal appearing osteoid. These dose response data further support the role of recombinant human bone morphogenetic protein-2 as a potent morphogen in bone regeneration.

Animals↗

Does this treatment work? Validation of an outcomes module for alcohol dependence.

The purpose of this study was to evaluate the outcomes of routine care administered to alcohol-dependent inpatients. The authors sought to validate a self-administered instrument that measures the types and extent of care delivered, the outcomes of that care, and casemix characteristics that influence the outcomes of care. Seventy-eight patients who were beginning inpatient treatment for alcohol dependence were recruited; 85% were followed 5 months later to examine cross-sectional and longitudinal relationships to gold standard assessments. The self-administered module demonstrated excellent agreement with structured interview assessments of diagnosis (kappa = .81), remission (kappa = .83), and change in severity of alcohol-related problems (r = .66 to .87). Casemix variables, particularly baseline severity, predicted change in alcohol consumption and functional status. The baseline module required 20 minutes for the average patient and 5 minutes for the average clinician to complete, with less than 2% missing data. Results indicated that the module measures key constructs with sufficient precision to assist clinicians and researchers in characterizing the degree to which routine inpatient care for alcohol dependence "works" in their patient population. The entire module is in the public domain and available free of charge to interested users.

Adult↗

Violence and remote area nursing.

The Federal government and others have accepted that violence is a problem in rural and remote communities across Australia. The issue of personal safety for Remote Area Nurses (RANs) living in remote areas has been mentioned in a number of State and Regional reports. However, to the knowledge of this research group, no systematic attempt to gather data on the incidence of violence experienced by RANs and other remote health workers has occurred. This study aims to redress the lack of data on the experience and description of violence against remote area nurses. Results indicate that remote area nurses are living with frequent threats to their personal safety while on duty, on call and off duty, and that violent incidents are often handled badly by employers, the community and remote area nurses themselves. Twenty-four-hour call is an employment requirement for 82% of respondents. Those required to be on call 24 hours experience episodes of violence more frequently. Despite nearly all of the respondents experiencing episodes of violence within the 12 months prior to the study, there was a tendency for remote area nurses, except in the case of physical violence, to perceive both the frequency and the severity of their experiences with violence as low and not personally directed.

Community Health Nursing↗

Radiation treatment of superior sulcus lung carcinoma.

The survival of patients with superior sulcus lung carcinoma and the effects of treatment were reviewed. From a prospective database of 4123 consecutive new patients with lung carcinoma, 131 (3.2%) cases of superior sulcus lung carcinoma were identified. Seventy-four patients were planned to receive radiation with palliative intent, 53 radical radiotherapy and one was observed only. The remaining three patients, with small-cell carcinoma, were treated with chemotherapy with or without radiotherapy. Of the 53 radically treated patients, nine were treated with pre-operative radiation prior to intended radical resection. Analysis was carried out on the effect on survival of performance status, nodal involvement, weight loss, vertebral body or rib involvement, treatment intent and radical combined modality treatment compared with radical radiation alone. The estimated median survival for the whole group was 7.6 months; for those treated radically it was 18.3 months, while for the palliatively treated patients it was 3.7 months. Radically treated patients with no initial nodal involvement had an estimated median survival of 22 months, while radically treated patients with nodal involvement had an estimated median survival of 8.4 months (P = 0.003). There were no statistically significant differences in survival between radically treated patients grouped according to initial weight loss, performance status, or vertebral body and rib involvement. Patients treated with pre-operative radiation did not survive significantly longer than patients treated with radiation alone, although the numbers are small.

Adult↗

Neurological outcome of severe cystic periventricular leukomalacia.

OBJECTIVE: To determine the neurological outcome of a cohort of premature babies having ultrasound diagnoses of severe cystic periventricular leukomalacia. METHODOLOGY: All neonatal intensive care unit admissions born at less than 35 weeks gestation or weighing less than 1500 g underwent serial cranial ultrasounds. Those developing severe bilateral cystic periventricular leukomalacia (12 patients) were then followed clinically to a mean age of 27.3 months. RESULTS: Ten of the 12 patients fulfilling strict ultrasound criteria survived. All had a major neurological handicap, all having spastic quadriparesis and visual impairments, with most suffering global developmental delay and epilepsy. CONCLUSIONS: Severe bilateral cystic periventricular leukomalacia results in major permanent handicap. It is currently impossible to identify most patients with this condition while they are being ventilated. Non-ultrasound techniques are needed to diagnose the condition earlier, and to give guidance to management.

Developmental Disabilities↗