Search PubMed⌕ Search

Biomedical subjects

M Martin

Publications and source records attributed to M Martin.

At least 397 records · Page 22Linked to original sources
PubMed1995

Immunoradiometric method and electrophoretic system compared for quantifying bone alkaline phosphatase in serum.

Agarose electrophoresis (Isopal, Beckman) and an immunoradiometric assay (IRMA) involving specific monoclonal antibodies (Ostase, Hybritech), two methods for the quantification of serum bone alkaline phosphatase (ALP, EC 3.1.3.1), a marker of osteoblastic activity, were compared in 293 patients: 79 with end-stage renal failure treated with hemodialysis and 214 with malignant disease. Overall correlation between the two methods was good (r = 0.92), except (a) for low values of bone ALP and (b) in some samples with high total liver ALP activity--both due to considerable cross-reactivity of the anti-bone ALP antibodies of the Ostase kit with liver ALP. This interference was not constant and was not evenly distributed across all concentrations of bone ALP. Low bone ALP determined with the IRMA (< or = 5 micrograms/L) was confirmed by electrophoresis (< or = 21 U/L), but bone ALP activity determined by electrophoresis to be low (< or = 21 U/L) was not correlated with the IRMA results. After standardizing our results by computing z-values for bone ALP, delta z (= zOstase - zIsopal) was significantly correlated with liver ALP activity (r = 0.73, P < 0.0001). We conclude that the IRMA for quantifying bone ALP is acceptable as a screening method. However, when high values for bone ALP are found with the Ostase method, confirmation by electrophoresis remains mandatory to rule out cross-reactivity with high amounts of liver ALP. For detecting low bone ALP activities, electrophoresis remains the method of choice.

Alkaline Phosphatase↗
PubMed1995

Selective T cell depletion with CD8-conjugated magnetic beads in the prevention of graft-versus-host disease after allogeneic bone marrow transplantation.

The effects of a new immunomagnetic method of selectively depleting CD8+ lymphocytes from donor bone marrow were studied in 29 patients undergoing transplantation from HLA-identical sibling (n = 20) or alternative (n = 9) donors. The direct immunomagnetic depletion method consistently removed > 95% of CD8+ cells and the non-specific loss of other cell subsets was only about 15%. Recovery of CFU-GM and BFU-e was on average > 100%. The final graft contained 0.9 +/- 0.6 x 10(8)/kg nucleated cells and 1.4 +/- 2.7 x 10(5)/kg CD8+ cells. Patients also received cyclosporine starting day -1. Engraftment occurred in 28 patients (97%), including three patients who received a non-TBI conditioning regimen. One patient receiving an unrelated transplant failed to engraft. Median time to ANC > 500 x 10(6)/L was 17 (12-23) days. Four of 20 patients receiving grafts from HLA-identical siblings (20%) developed acute GVHD grade > or = II. However, five of eight patients with grafts from alternative donors (63%) had grade > or = II GVHD. Nearly all patients developed fever around day 7, accompanied by fluid overload, mild skin rash and shortness of breath. This syndrome necessitated treatment with steroids. Immunomagnetic CD8 depletion is a simple and reproducible method of selective T cell depletion. In combination with cyclosporine it appears to be effective in the prevention of severe acute GVHD in HLA-identical sibling transplants, but not in transplants from less perfectly matched donors.

Adult↗
PubMed1995

Comparison of nasogastric tube securing methods and tube types in medical intensive care patients.

BACKGROUND: Nasogastric tube displacement can result in serious complications such as aspiration and inadvertent migration of the tube into the lungs. Replacement of the tubes is costly, time- and effort-intensive, uncomfortable for the patients, and potentially dangerous. OBJECTIVE: To determine the best of three methods for securing nasogastric tubes in a medical intensive care population and to identify variables related to the failure of tube securing methods. METHODS: A convenience sample of 103 patients requiring duodenal or standard gastric tubes for feeding, medication delivery, or decompression were randomly assigned to one of three taping methods: pink tape, clear tape, or "butterfly," for a total of 264 taping episodes. Data collection included the mean time until failure of the securing methods as well as variables such as patient alertness and mobility. RESULTS: The mean time until failure was 100 hours with pink tape versus 56 hours with clear tape and 30 hours with the "butterfly." Differences were significant. Duodenal tubes stayed secured longer than standard sump tubes (mean time until failure was 86 vs 41 hours) for all taping methods, but not significant relationship was demonstrated between mean time until failure and variables such as alertness, sedation, confusion, mobility, and the use of restraints. CONCLUSION: Our results showed that the pink tape method was superior. Nasogastric tube securing methods in adult critical care patients vary in efficacy and should be selected carefully.

Adhesives↗
PubMed1995

[Subclavian vein thrombosis: epidemiologic data of the PHLEKO (phlebothrombosis conservative treatment) Study].

This is a report of 91 cases of subclavian vein thrombosis. The data are derived from the PHLECO-study (Phlebothrombosis-Conservative treatment) which is a multicenter investigation on the fate of 2088 deep vein thromboses as diagnosed by phlebography. In this cohort the subclavian vein thrombosis incidence was recorded at 4.36%. The interval between first symptoms and hospital admission lasted 3.90 days. The average patient's age was 46.3 years. The genders were evenly distributed. The causes of subclavian vein thromboses were in 29.7% traumatic (effort thrombosis, catheter manipulation), in 31.9% symptomatic (accompanying other diseases), and in 38.4% idiopathic (cause unknown). Fibrinolytic therapy was carried out in 49.4% of the cases, the remainder received anticoagulants. Patients with acute subclavian vein thrombosis and conservative treatment (no fibrinolytic therapy) stayed for 18.8 days in the hospital. No instances of pulmonary embolism, either fatal or non-fatal, were recorded.

Adult↗
PubMed1995

Lowering physician hospital resource consumption using low-cost low-technology computing.

Anderson Area Medical Center physicians have been provided disease and procedure specific profiles of their practice experience for more than five years. For four years, physicians were provided reporting, in a variety of formats, detailing their clinical outcomes and consumption of hospital resources in treating patients with acute myocardial infarction (AMI), pneumonia, cholecystectomy, stroke, congestive heart failure (CHF), and total hip replacement. For the past eighteen months physicians have been provided a uniform format of monthly physician-specific reporting for stroke, AMI, pneumonia, diabetes, CHF, cholecystectomy, total hip replacement, newborn delivery, angina, and hernia repair. Using only a modest PC platform with database, word processing, and graphics programs operating in a DOS environment, an effective disease/procedure reporting program is provided to medical staff with 3 person-days of effort per month.

Computer Systems↗
PubMed1995

Evaluation of a problem-based access knowledge system using triangulation methods.

A microcomputer-based system designed to provide nurses and physicians access to expert synthesized knowledge in the area of pulmonary arterial waveform troubleshooting has been developed and implemented. Evaluation using triangulation methods show that there was a substantive increase in knowledge in both nurses and physicians.¿.

Attitude of Health Personnel↗
PubMed1995

Oxygen transport.

The most important factor in the development of complex life forms is the ability to deliver oxygen to cells within complex tissues and organs. Hemoglobin plays a significant role in this scheme. Oxygen transport is a complex phenomenon that encompasses the oxygen content, oxygen delivery mechanisms, and oxygen use. All three components must operate appropriately if the organism is to function and survive.

Biological Transport↗
PubMed1994

In planta transformation of Arabidopsis thaliana.

Transformants of Arabidopsis thaliana can be generated without using tissue culture techniques by cutting primary and secondary inflorescence shoots at their bases and inoculating the wound sites with Agrobacterium tumefaciens suspensions. After three successive inoculations, treated plants are grown to maturity, harvested and the progeny screened for transformants on a selective medium. We have investigated the reproducibility and the overall efficiency of this simple in planta transformation procedure. In addition, we determined the T-DNA copy number and inheritance in the transformants and examined whether transformed progeny recovered from the same Agrobacterium-treated plant represent one or several independent transformation events. Our results indicate that in planta transformation is very reproducible and yields stably transformed seeds in 7-8 weeks. Since it does not employ tissue culture, the in planta procedure may be particularly valuable for transformation of A. thaliana ecotypes and mutants recalcitrant to in vitro regeneration. The transformation frequency was variable and was not affected by lower growth temperature, shorter photoperiod or transformation vector. The majority of treated plants gave rise to only one transformant, but up to nine siblings were obtained from a single parental plant. Molecular analysis suggested that some of the siblings originated from a single transformed cell, while others were descended from multiple, independently transformed germ-line cells. More than 90% of the transformed progeny exhibited Mendelian segregation patterns of NPTII and GUS reporter genes. Of those, 60% contained one functional insert, 16% had two T-DNA inserts and 15% segregated for T-DNA inserts at more than two unlinked loci. The remaining transformants displayed non-Mendelian segregation ratios with a very high proportion of sensitive plants among the progeny.(ABSTRACT TRUNCATED AT 250 WORDS)

Agrobacterium tumefaciens↗
PubMed1994

A prospective randomized trial comparing sequential ganciclovir-high dose acyclovir to high dose acyclovir for prevention of cytomegalovirus disease in adult liver transplant recipients.

Cytomegalovirus disease is an important cause of morbidity following liver transplantation. To date there has not been an effective prophylaxis for CMV disease after liver transplantation. One hundred forty-three patients were randomized to receive either high dose oral acyclovir (800 mg 4 times a day) alone for 3 months after transplantation (acyclovir group) or intravenous ganciclovir (5 mg/kg twice a day) for 14 days followed by high dose oral acyclovir to complete a 3-month regimen (ganciclovir group). Of 139 patients available for evaluation, 43 of 71 (61%) patients from the acyclovir group developed CMV infection compared with 16 of 68 (24%) from the ganciclovir group (relative risk, 3.69; 95% confidence interval, 2.07-6.56; P < 0.00001). Of those randomized, CMV disease was seen in 20 (28%) of the acyclovir group compared with 6 (9%) of the ganciclovir group (relative risk, 5.11; 95% confidence interval, 2.05-12.75; P = 0.0001). The median time to onset of CMV infection was 45 days in the acyclovir group compared with 78 days in the ganciclovir group (P = 0.004). The median time to onset of CMV disease was 40 days in the acyclovir group compared with 78 days in the ganciclovir patients (P = 0.02). With respect to primary CMV infection, there was no difference in the rates in the 2 groups, but tissue invasive disease and recurrent CMV disease were less frequent in the ganciclovir group. It is concluded that a course of 2 weeks of ganciclovir immediately after transplantation followed by high dose oral acyclovir for 10 weeks is superior to a 12-week course of high dose oral acyclovir alone for prevention of both CMV infection and CMV disease after liver transplantation. However, the lack of significant effect in seronegative recipients who received grafts from seropositive donors suggests that other strategies are needed to prevent CMV infection in this high risk population.

Acyclovir↗
PubMed1994

Partial trisomy 16p in an adolescent with autistic disorder and Tourette's syndrome.

A partial trisomy 16p was identified in a 14-year-old male adolescent with autistic disorder. He additionally showed complex motor and vocal phenomena, including some simple tics which had first appeared in childhood. Whereas these simple tics were of subclinical significance, an additional diagnosis of Tourette's syndrome (TS) appears justified. The case report illustrates the diagnostic difficulties in assessing psychiatric symptomatology associated with both disorders, especially complex motor and vocal phenomena. The cytogenetic finding is discussed critically in the light of other chromosome abnormalities reported in both TS and autistic disorder. Chromosome 16p should be considered as a candidate region especially for autistic disorder.

Adolescent↗
PubMed1994

Survival in medically treated patients with homozygous beta-thalassemia.

BACKGROUND: The prognosis of patients with homozygous beta-thalassemia (thalassemia major) has been improved by transfusion and iron-chelation therapy. We analyzed outcome and prognostic factors among patients receiving transfusions and chelation therapy who had reached the age at which iron-induced cardiac disease, the most common cause of death, usually occurs. METHODS: Using the duration of life without the need for either inotropic or antiarrhythmic drugs as a measure of survival without cardiac disease, we studied 97 patients born before 1976 who were treated with regular transfusions and chelation therapy. We used Cox proportional-hazards analysis to assess the effect of prognostic factors and life-table analysis to estimate freedom from cardiac disease over time. RESULTS: Of the 97 patients, 59 (61 percent) had no cardiac disease; 36 (37 percent) had cardiac disease, and 18 of them had died. Univariate analysis demonstrated that factors affecting cardiac disease-free survival were age at the start of chelation therapy (P < 0.001), the natural log of the serum ferritin concentration before chelation therapy began (P = 0.01), the mean ferritin concentration (P < 0.001), and the proportion of ferritin measurements exceeding 2500 ng per milliliter (P < 0.001). With stepwise Cox modeling, only the proportion of ferritin measurements exceeding 2500 ng per milliliter affected cardiac disease-free survival (P < 0.001). Patients in whom less than 33 percent of the serum ferritin values exceeded 2500 ng per milliliter had estimated rates of survival without cardiac disease of 100 percent after 10 years of chelation therapy and 91 percent after 15 years. CONCLUSIONS: The prognosis for survival without cardiac disease is excellent for patients with thalassemia major who receive regular transfusions and whose serum ferritin concentrations remain below 2500 ng per milliliter with chelation therapy.

Adult↗
PubMed1994

Evidence that intravenously administered alpha-galactosyl carbohydrates reduce baboon serum cytotoxicity to pig kidney cells (PK15) and transplanted pig hearts.

Methods of inhibiting the hyperacute antibody-mediated rejection that occurs when pig organs are transplanted into primates have been investigated using the baboon as a potential recipient. Baboons were treated with different regimens that included combinations of (1) splenectomy, (2) pharmacologic immunosuppression (CsA, cyclophosphamide, corticosteroids +/- methotrexate), and (3) intravenous infusion of oligosaccharides. The cytotoxicity of the serum was then assessed on cultures of pig kidney cells (PK15). Unmodified serum caused approximate 65-100% pig cell destruction. Splenectomy and/or pharmacologic immunosuppression, and infusions of dextran, dextrose or mannitol, did not result in any reduction of cytotoxicity. Infusions of melibiose and/or arabinogalactan, both of which have terminal non-reducing alpha-galactose, however, decreased relative PK15 cell damage significantly in a dose-dependent manner. At high concentrations (< or = 50 g/hr), complete inhibition of cytotoxicity was achieved in 4 of 15 baboons. The extracorporeal immunoadsorption of baboon serum utilizing immunoaffinity columns of melibiose also resulted in a significant reduction (of approximately 80%) in cytotoxic effect. In 1 baboon, melibiose and arabinogalactan infusion delayed vascular rejection of a pig cardiac xenograft from 10 min to about 12 hr, at which time the baboon died from the toxic effects of the carbohydrate infusion. These observations (1) add further support to the role that anti-alpha-galactosyl antibodies play in the hyperacute rejection of pig tissues transplanted into primates, and (2) demonstrate that serum cytotoxicity can be reduced by the intravenous infusion of alpha-galactosyl oligosaccharides or by extracorporeal immunoadsorption using these carbohydrates.

Animals↗
PubMed1994

Concomitant p53 gene mutation and increased radiosensitivity in rat lung embryo epithelial cells during neoplastic development.

A rat lung cell population had been treated with benzo(a)pyrene, and a set of different epithelial cell lines was derived from it. These cell lines carried either a wild-type or mutant p53 gene and represented grading states of neoplastic development. We demonstrate here that the cells lacking both wild-type p53 alleles display a significant decrease in survival after gamma-irradiation with doses of 2 to 12 Gy, compared with their counterparts carrying wild-type p53 alleles. This is the first reported model in which cells bearing a mutation of the p53 gene display enhanced sensitivity to ionizing radiation.

Animals↗