PubMed Health⌕ Search

Biomedical subjects

J Goguen

Publications and source records attributed to J Goguen.

11 recordsLinked to original sources

Antibiotic susceptibility of isolates of Bacillus anthracis, a bacterial pathogen with the potential to be used in biowarfare.

Bacillus anthracis is a bacterial species that could be used in a bioterrorist attack. We tested a collection of isolates with a range of relevant antimicrobial compounds. All isolates tested were susceptible to ciprofloxacin and doxycycline. Penicillin and amoxicillin, with or without clavulanate, showed in vitro activity against all B. anthracis isolates. Ceftriaxone demonstrated lower-level in vitro activity compared to penicillin-related compounds against B. anthracis. In vitro data from this study are in keeping with available guidelines.

Anthrax↗

A novel united network for organ sharing region kidney allocation plan improves transplant access for minority candidates.

BACKGROUND: We report the consequences of a novel kidney allocation system on access of non-Caucasians (NC) to kidney transplantation. This new plan has provided a balance of allocation determinants between time waiting, HLA match, and geography (population density between donor and recipient center). METHODS: Three sequential systems of regional allocation were analyzed: period I (September 1994 to September 1996), period II (September 1996 to November 1997), and period III (December 1997 to March 1 1999). Periods II and III are reflective of the new allocation plan. RESULTS: During periods II and III, the NC rate of kidney transplantation increased closer to the NC proportion on the wait list, comparatively exceeding the national UNOS data. There was no statistical difference in regional mean wait time between Caucasian and NC. Improvements in access to transplantation for NCs between period I and periods II and III appear to be related to changes in geographic allocation weight from local unit to population density points, to the inclusion of the entire region in the plan, and to the deletion of intermediate degrees of B/DR mismatching in the revised plan. Despite the increased proportion of NCs on the wait list from period I to period III, the percentage difference between the proportion of NCs waiting on the list and the proportion NCs receiving a transplant fell from 7.8% to 4.9%. CONCLUSIONS: These data demonstrate that this new allocation plan was associated with improved access of minority candidates to transplantation. The broadening of geographic allocation and the alteration of HLA points appear to permit a more favorable opportunity for renal transplantation to NC candidates. selection, compared to the UNOS formula. In this report, we analyze the consequences of the Region 1 allocation system on the access of non-Caucasian (NC) candidates to cadaver donor kidney transplantation.

Health Services Accessibility↗

A new allocation plan for renal transplantation.

BACKGROUND: A novel plan of renal allograft allocation has been conducted by United Network for Organ Sharing Region 1 transplant centers since September 3, 1996, based upon HLA matching, time waiting, and population distance points. The objectives of this plan were to achieve a balance between increasing the opportunity of renal transplantation for those patients listed with long waiting times and promoting local organ donor availability. METHODS: A single list of candidates was formulated for each cadaver donor, assigning a maximum of 8 points for time waiting, a maximum of 8 points for population distance from the donor hospital, and HLA points based upon the degree of B/DR mismatch. Additional points were awarded to a cross-match-negative patient with a panel-reactive antibody of >80%, and to pediatric patients. RESULTS: The total number of kidneys transplanted to patients who had waited >3 years was 100 (46%), and to patients who had waited >2.5-3 years was 29 (13%). However, the total number of kidneys transplanted to patients with the maximum population distance points was only 72 (33%). Thus, although the plan achieved a favorable distribution of kidneys to patients with longer waiting times (nearly 60%), the other, equally important objective of promoting local donor availability was not initially accomplished. Moreover, minor HLA B/DR differences between the donor and the recipient (i.e., not phenotypically matched) were unexpectedly consequential in determining allocation. As a result of these observations, the following adjustments were made in the plan (as of December 3, 1997): a maximum of 10 points for population distance, a maximum of 8 points for time waiting (both by a linear correlation), and the retention of HLA points for 0 B/DR mismatch only. After these interval changes, the percentage of patients receiving a kidney with some population distance points increased from 85% to 96%. Conclusions. We have shown that a heterogeneous region of multiple transplant centers can devise (and modify) an innovative and balanced plan that provides an equitable system of allocation for an ever-increasing number of patients.

Adolescent↗

Earth-Based Observations of the Galileo Probe Entry Site

Earth-based observations of Jupiter indicate that the Galileo probe probably entered Jupiter's atmosphere just inside a region that has less cloud cover and drier conditions than more than 99 percent of the rest of the planet. The visual appearance of the clouds at the site was generally dark at longer wavelengths. The tropospheric and stratospheric temperature fields have a strong longitudinal wave structure that is expected to manifest itself in the vertical temperature profile.

Journal Article↗

Can a severe degree of ketoacidosis develop overnight?

Insulin-dependent diabetes mellitus in poor control, alcohol intake associated with extracellular fluid volume contraction, or hypoglycemia may each lead to an increased rate of production of ketoacids. Generally, several days of illness are required before ketoacidosis becomes severe. Two clinical examples are presented to suggest that a severe degree of ketoacidosis may develop over a short period of time, literally overnight. In both examples, there was the ingestion of a modest amount of ethanol. From a quantitative analysis of factors that may influence the rate of production and removal of ketoacids, the following were deduced. Contributing factors to the very rapid development of maximal ketoacidosis could include the absence of a lag period for the conversion of ethanol to acetyl-coenzyme A in the liver and an impaired ability of the brain and kidneys to oxidize ketoacids, especially if these ketoacids are produced very rapidly and/or if less metabolic work is performed by these organs. In special settings, ketoacidosis may develop more rapidly than is generally appreciated.

Adult↗

Collision of comet Shoemaker-Levy 9 with Jupiter observed by the NASA infrared telescope facility.

The National Aeronautics and Space Administration (NASA) Infrared Telescope Facility was used to investigate the collision of comet Shoemaker-Levy 9 with Jupiter from 12 July to 7 August 1994. Strong thermal infrared emission lasting several minutes was observed after the impacts of fragments C, G, and R. All impacts warmed the stratosphere and some the troposphere up to several degrees. The abundance of stratospheric ammonia increased by more than 50 times. Impact-related particles extended up to a level where the atmospheric pressure measured several millibars. The north polar near-infrared aurora brightened by nearly a factor of 5 a week after the impacts.

Ammonia↗

Phenotypic characteristics of lymphocyte populations isolated from middle gestation human placenta.

In order to characterize the phenotypic composition of populations of lymphoid cells in maternal and fetal tissues during the period of middle gestation, mononuclear cells were isolated from maternal peripheral blood, fetal spleen, fetal thymus and placenta of 18-24 week pregnancies. Peripheral blood and placental isolates were stained for a number of lymphoid cell markers by indirect immunofluorescence and analyzed by flow cytometry. Studies were performed on both freshly isolated mononuclear cell preparations and in vitro cultured cells after selective expansion in interleukin 2 (IL2). Fresh placental mononuclear cell isolates were an average 20% CD3+; their CD4/CD8 ratios varied among individuals. An average of 68% of the lymphocytes isolated from maternal peripheral blood were CD3+. Placental and maternal peripheral blood isolates had comparable percentages of CD16+ and CD20+ cells, while CD56+ cells were present at significantly greater numbers in the lymphocyte compartment of placenta (17%) than in peripheral blood (3%; P < 0.01). Lymphocyte isolates were expanded by culture with IL2 and PHA and stained to determine if propagated lymphocyte populations are representative of initial isolates. Expansion of all lymphocyte isolates favored CD3 phenotypes and CD8 phenotypes. Compared to expanded placenta-derived populations, expanded peripheral blood lymphocytes were similar with regard to percentages of all phenotypes except gamma/delta T cells which represented more of placental lymphocytes (10%) than peripheral lymphocytes (5%; P < 0.01). Surface HLA typing determined propagated placenta-derived lymphocytes to be of maternal and not fetal origin. In vitro propagation of placental mononuclear cell isolates may therefore provide populations of maternal CD3+ lymphocytes for assessment of function and specificity.

Antigens, CD↗

Micrococcal nuclease cleavage of chromatin displays nonrandom properties.

A statistical analysis of the products of digestion of chicken erythrocyte chromatin by micrococcal nuclease was used to test for randomness of the cutting process. DNA fragment size classes corresponding to mononucleosome, dinucleosome, trinucleosome, tetranucleosome, and all fragments larger than tetranucleosome were evaluated. In every case, fragments in the mononucleosome and greater-than-tetranucleosome classes were produced in excess of the level expected on the basis of random cleavage while those in the dinucleosome-tetranucleosome classes exhibited a shortage. The pattern of nonrandomness appears to depend on substrate size: the magnitude of deviations from randomness was large when substrates of genomic size are compared with polynucleosomal segments whereas the direction of deviation is identical. Nonrandomness was independent of ionic conditions known to affect the state of chromatin condensation and also appeared to be unaffected by depletion of histones H1 and H5. The possible universality of nonrandom cleavage was suggested when other data from the literature was analyzed. Some possible mechanisms to account for this property are discussed.

Animals↗

Improved B cell typing for HLA-DR using nylon wool column enriched B lymphocyte preparations.

A rapid, simple procedure for preparing B lymphocytes using nylon wool has been devised. When mixtures of T lymphocytes, B lymphocytes, and monocytes are applied to nylon wool columns, B lymphocytes can then be removed, virtually free of monocytes. Such preparations (Ad) are 85 +/- 6% SIg+ and have only 3 +/- 1% monocyte contamination. The yield from peripheral blood averages 5% of all mononuclear cells. In contrast, the E rosette depletion method (E-) yields cells which are only 64 +/- 5% SIg+ and have 25 +/- 7% monocyte contamination. The superiority of the nylon method for HLA-DR typing was demonstrated in a comparative study of Ad and E- with eight normal individuals. Cytotoxic scores were higher and a large number of reactions, representing DRw groups and additional cross-reactions, was detected.

B-Lymphocytes↗