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K Love

Publications and source records attributed to K Love.

At least 19 recordsLinked to original sources
PubMed1998

Analysis of 1.9 Mb of contiguous sequence from chromosome 4 of Arabidopsis thaliana.

The plant Arabidopsis thaliana (Arabidopsis) has become an important model species for the study of many aspects of plant biology. The relatively small size of the nuclear genome and the availability of extensive physical maps of the five chromosomes provide a feasible basis for initiating sequencing of the five chromosomes. The YAC (yeast artificial chromosome)-based physical map of chromosome 4 was used to construct a sequence-ready map of cosmid and BAC (bacterial artificial chromosome) clones covering a 1.9-megabase (Mb) contiguous region, and the sequence of this region is reported here. Analysis of the sequence revealed an average gene density of one gene every 4.8 kilobases (kb), and 54% of the predicted genes had significant similarity to known genes. Other interesting features were found, such as the sequence of a disease-resistance gene locus, the distribution of retroelements, the frequent occurrence of clustered gene families, and the sequence of several classes of genes not previously encountered in plants.

Arabidopsis↗
PubMed1997

FCA, a gene controlling flowering time in Arabidopsis, encodes a protein containing RNA-binding domains.

A strong promoter of the transition to flowering in Arabidopsis is encoded by FCA. FCA has been cloned and shown to encode a protein containing two RNA-binding domains and a WW protein interaction domain. This suggests that FCA functions in the posttranscriptional regulation of transcripts involved in the flowering process. The FCA transcript is alternatively spliced with only one form encoding the entire FCA protein. Plants carrying the FCA gene fused to the strong constitutive 35S promoter flowered earlier, and the ratio and abundance of the different FCA transcripts were altered. Thus, FCA appears to be a component of a posttranscriptional cascade involved in the control of flowering time.

Amino Acid Sequence↗
PubMed1997

Emergence of further serotypes of multiple drug-resistant Streptococcus pneumoniae in Queensland.

We describe 27 cases of multiple drug-resistant pneumococcal infection in Queensland children (7 cases) and adults (20 cases), between February 1995 and October 1996. Seven patients had invasive disease. Serotypes were those commonly associated with paediatric infections and included types 19F (15 strains), 14 (6), 23F (4), 6A (1) and 19A (1). No rifampicin or vancomycin resistance was encountered. However, pneumococci fully resistant to cotrimoxazole, erythromycin and tetracycline were isolated from 25 of 27 cases (93%). Strains with high level resistance to penicillin and chloramphenicol were also recovered from 16 (59%) and 19 (70%) patients respectively. Twelve of 16 penicillin-resistant isolates showed intermediate resistance to ceftriaxone and two strains were fully resistant to this antibiotic. Clones of types 19F and 14 pneumococci, each with two distinctive resistance patterns, appear to be established in south-east Queensland.

Adult↗
PubMed1997

Description of 31 YAC contigs spanning the majority of Arabidopsis thaliana chromosome 5.

In order to generate a physical map of Arabidopsis thaliana chromosome 5, 142 molecular markers mapping chromosome 5 have been used in colony hybridization experiments with four Arabidopsis, ecotype Columbia, yeast artificial chromosome (YAC) libraries. This resulted in 634 YAC clones being anchored on chromosome 5. Southern blot analysis confirmed their positioning and provided data, which along with knowledge of the sizes of all the YAC clones, enabled the clones to be arranged into 31 contigs. Genetic mapping of markers located within 29 of these contigs on the Landsberg erecta/Columbia recombinant inbred lines allowed positioning of the contigs along the chromosome. A high proportion of the YAC clones were found to contain chimaeric inserts. The availability of this YAC contig map will accelerate chromosome-walking experiments, provide substrates for large-scale genomic sequencing projects and facilitate the mapping of new probes to this chromosome.

Arabidopsis↗
PubMed1996

Detailed description of four YAC contigs representing 17 Mb of chromosome 4 of Arabidopsis thaliana ecotype Columbia.

The detailed arrangement of 563 YAC clones comprising four contigs covering approximately 17 Mbp of chromosome 4 is presented. YAC clones were positioned relative to each other and to markers by taking into account marker and end fragment hybridization data and the sizes of all YAC clones. This analysis made it possible to estimate physical distances between the majority of chromosome 4 markers. It also identified a relatively large number of YAC clones containing chimaeric inserts. The YAC contig map of the Columbia ecotype presents an important resource for map-based cloning experiments, rapid mapping of DNA sequences and large-scale genomic sequencing programs.

Arabidopsis↗
PubMed1995

Physical map and organization of Arabidopsis thaliana chromosome 4.

A physical map of Arabidopsis thaliana chromosome 4 was constructed in yeast artificial chromosome clones and used to analyze the organization of the chromosome. Mapping of the nucleolar organizing region and the centromere integrated the physical and cytogenetic maps. Detailed comparison of physical with genetic distances showed that the frequency of recombination varied substantially, with relative hot and cold spots occurring along the whole chromosome. Eight repeated DNA sequence families were found in a complex arrangement across the centromeric region and nowhere else on the chromosome.

Arabidopsis↗
PubMed1993

Effect of ethanol on Kupffer cell function.

Kupffer cells are resident macrophages in the liver and are important in both local and systemic immune responses. We evaluated the ability of Kupffer cells in vitro to respond to immune stimulation after both acute exposure to ethanol and after long-term ethanol consumption of ethanol. Triplets of female Wistar rats were fed a liquid diet containing 0, 12, or 36% ethanol isocalorically for 112 days. When killed, the Kupffer cells were isolated by collagenase perfusion and adhered to plastic 24-well plates. They were then stimulated with 10 micrograms/ml lipopolysaccharide for 4.5 hr. Synthesis of procoagulant activity (PCA) and tumor necrosis factor (TNF), expressions of macrophage response to immune stimuli, were measured by a one-step clotting assay and L929 cytotoxicity assay, respectively. Within each of the 10 triplets, PCA and TNF levels were normalized and expressed as a percentage of the zero ethanol isocaloric control rat. The high ethanol group had significantly lower baseline and stimulated PCA and TNF levels than the low ethanol group. For evaluation of the effect of acute exposure to ethanol, Kupffer cells were stimulated with lipopolysaccharide and varying concentrations (0-400 mg/dl) of ethanol. Cells were incubated for 4.5 hr and assayed for PCA and TNF activity. There was dose-dependent inhibition of PCA and TNF, with increasing concentrations of ethanol. These results indicate that whereas exposure to high levels of ethanol depresses Kupffer cell function, lower levels may be immunostimulatory.

Alcoholism↗
PubMed1992

Response to hepatitis B vaccination by liver transplant candidates.

Liver transplantation (OLTx) is a procedure offered to individuals with advanced liver disease who are expected to live less than a year. Despite improvement in the care of transplant recipients, these patients are exposed to large volumes of blood and, as a result, are at risk to acquire hepatitis. Currently, the only vaccines available for the prevention of hepatitis are those that induce a response to HBsAg. In this study, 144 patients awaiting OLTx and 15 controls were vaccinated three times, once a month, intramuscularly in the deltoid using the Merck Hepatovax plasma-derived vaccine. This schedule was continued regardless of whether or not OLTx occurred before the series was completed. For the 15 controls, the response rate was 93% and for individuals with end-stage liver disease, it ranged from 44 to 54% (P less than 0.004). No difference in the percentage of those developing antibody was detected between groups based upon disease indication or whether the vaccination series was completed before or after OLTx. Of the following: WBC, lymphocytes (percent and number), CD3+ cells (percent and number), CD4+ cells (percent and number), CD8+ cells (percent and number), CD4+/CD8+ ratio, and B cells (percent and number), only the absolute WBC (P less than 0.05) distinguished between those who did and did not develop antibody.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Detection of the relationship between moderate alcoholic beverage consumption and serum levels of estradiol in normal postmenopausal women: effects of alcohol consumption quantitation methods and sample size adequacy.

The purpose of this study was to evaluate the detectability of an effect of moderate alcoholic beverage consumption on the biologic correlate of postmenopausal estradiol levels. Total weekly consumption and beverage-specific intake were assessed using both self-reported usual consumption information and prospective food record data. In terms of total weekly drinks, discrepancies were observed in 35 of the 101 women who reported alcohol use; no consistent pattern of overreporting/underreporting was seen. Although the two alcohol estimates were highly correlated, the relationship between estradiol levels and total weekly alcohol intake was found to be detectable when alcohol consumption based on the food record data was analyzed, but not when the self-report data were examined in a two-tailed hypothesis-testing situation. Evaluating the association between postmenopausal estradiol levels and the two estimates of alcohol intake in random samples of varying sample sizes generated from the mother population of 128 normal postmenopausal women confirmed the finding that the prospectively obtained alcohol data better predict the relationship. Based on the results of this study, it must be concluded that self-reported usual alcohol consumption data must be used with caution when examining an association between alcohol intake and a biologic effect.

Alcohol Drinking↗
PubMed1991

Treatment of end-stage chronic obstructive pulmonary disease with double lung transplantation.

Six patients with end-stage emphysema (age 44 +/- 2 years) underwent double lung transplantation (Tx) from June 1988 through May 1990. All suffered from severe inanition and required oxygen therapy. The ischemic time was 193 +/- 28 minutes. Post-Tx immune suppression was OKT3 (14 days), cyclosporine (trough levels of 150 +/- 25 ng/ml), azathioprine to keep WBC at 3,000 to 5,000/cu mm (1 to 3.0 mg/kg/day) and following OKT3, a tapering prednisone regimen. Two rejection episodes that occurred in two patients on post-Tx day 5 and 10 were treated with bolus doses of methylprednisolone. The mean hospital stay was 32 +/- 7 days (range, 20 to 69 days). Four patients required treatment of cytomegalovirus (CMV) infection: gastritis (+donor, +recipient) in one and CMV pneumonia in two (+donor, -recipient). A fourth (+donor, -recipient) had right-sided Candida empyema six weeks post-Tx, developed CMV and staphylococcal sepsis, and died 64 days post-Tx. One patient required pyloroplasty eight weeks post-Tx and one patient underwent tracheal suture line repair at eight weeks. During a follow-up of 81 patients months (range, 8 to 24 months), one patient had developed Epstein-Barr viral (EBV) induced lymphoproliferative disease in the lung and one patient had developed EBV lymphoma. Three patients are at work, one is continuing rehabilitation, and one is at home. Double lung Tx offers a definitive benefit to patients with emphysema; however, a prolonged postoperative course can be expected. Viral infections remain serious but treatable problems.

Adult↗
PubMed1991

An international study of the relationship between alcohol consumption and postmenopausal estradiol levels.

Because of the beneficial effect of estrogens on the risk of cardiovascular disease and osteoporosis in postmenopausal women, the factors which influence endogenous postmenopausal estrogen levels are of substantial importance. The major source of postmenopausal estrogen is the aromatization of androgens to estrogens. Because alcohol is reported to increase aromatization rates, the relationship between serum estradiol and moderate alcohol consumption was examined in a group of 128 healthy Pittsburgh postmenopausal women, and a significant direct association was found. In order to address the generalizability of this finding, 3 comparable study populations of healthy postmenopausal women were recruited: 62 in Copenhagen, 34 in Lisbon and 20 in Madrid. Although no association was detected in the Madrid study sample, in both the Copenhagen and Lisbon study populations, not only were estradiol levels significantly increased in alcohol users as compared to abstainers, but also estradiol levels were significantly correlated with total weekly drinks consumed. Based on these findings in study samples of healthy postmenopausal women from Pittsburgh, Copenhagen and Lisbon, we conclude that the increase in estradiol levels seen with moderate alcoholic beverage consumption is not an isolated finding and speculate that moderate alcohol consumption by healthy postmenopausal women may have beneficial effects.

Alcohol Drinking↗
PubMed1988

Infectious complications in four long-term recipients of the Jarvik-7 artificial heart.

This article describes the infectious complications that occurred among four of the longest-term recipients of the Jarvik-7 artificial heart. Infection arising from the drive lines, with spread to the mediastinal periprosthetic space, was the major limiting factor in long-term use of the device in these patients. Periprosthetic infections were due to coagulase-negative staphylococci, Staphylococcus aureus, Pseudomonas aeruginosa, and other Pseudomonas species. Other infectious complications incurred by some of the patients included pneumonia, empyema, urinary tract infection, and intravascular line sepsis with Candida. Intensive antimicrobial therapy for prolonged periods seemed to suppress but not to eradicate infection and was accompanied by the appearance of multiresistant bacterial strains. Complications of antimicrobial therapy included diarrhea secondary to overgrowth with Clostridium difficile in two patients. Use of the current device for more than 30 days should be considered extraordinary and should be reserved for patients for whom no other form of life support is available.

Adult↗
PubMed1977

Diarrhea associated with clindamycin and ampicillin therapy: preliminary results of a cooperative study.

Patients treated with clindamycin were monitored for development of diarrhea and colitis in a cooperative study at three hospitals in Edmonton, Toronto, and Winnipeg, Canada. Ampicillin-treated patients were matched with clindamycin-treated patients. Diarrhea occurred in 62 (18%) of 343 clindamycin-treated patients compared with 16 (5%) of 315 ampicillin-treated patients (P less than 0.001). Among the three hospitals, the rate of diarrhea associated with clindamycin therapy ranged from 10% to 23% compared with 0 to 10% for ampicillin therapy. The only identified risk factor in the development of diarrhea was increased age; clindamycin-associated diarrhea occurred in 18 (46%) of 39 patients greater than or equal to 60 years old. No correlation was observed between the risk of diarrhea and the duration of treatment, total dosage of drug, route of administration, or type of underlying disease. Pseudomembranous colitis was diagnosed in seven (2%) of 343 patients treated with clindamycin and in one (0.3%) of 315 patients treated with ampicillin.

Administration, Oral↗
PubMedDate not supplied

Contrast radiography of the lower urinary tract in the management of obstructive urolithiasis in small ruminants and swine.

Contrast radiographic visualization of the small ruminant and porcine lower urinary tract is an infrequently used modality for the evaluation and management of obstructive urolithiasis. The administration of contrast medium through a tube cystostomy catheter used to divert urine flow until the resolution of the obstruction may provide an easy method to evaluate the status of the urethral obstruction. Contrast fluoroscopy is utilized to monitor and visualize therapeutic flushing of the urethra. A review of 26 patients seen at the Veterinary Medical Teaching Hospital suggested that among the radiographic techniques used, positive contrast normograde cystourethrography through the tube cystostomy catheter allowed the best visualization of the lower urinary tract structures and enabled assessment of the resolution of the obstructive lesion.

Animals↗