PubMed Health⌕ Search

Biomedical subjects

J McKnight

Publications and source records attributed to J McKnight.

36 records · Page 2Linked to original sources

A randomized trial comparing ceftazidime alone with combination antibiotic therapy in cancer patients with fever and neutropenia.

To assess the efficacy of single-agent therapy relative to standard combination antibiotic therapy for the initial management of fever and neutropenia in cancer patients, we conducted a randomized trial comparing ceftazidime alone with a combination of cephalothin, gentamicin, and carbenicillin. Of 550 evaluable episodes of fever and neutropenia, 282 were treated with ceftazidime alone and 268 with the combination. All episodes were evaluated for responses at 72 hours after the start of treatment and at resolution of the neutropenia. Of the patients with unexplained fever who were given ceftazidime alone, 99 percent were alive at 72 hours and 98 percent were alive when the neutropenia resolved, as compared with 100 percent and 98 percent, respectively, of those given combination therapy. Of the patients with documented infection who were given ceftazidime alone, 98 percent were alive at 72 hours and 89 percent when the neutropenia resolved, as compared with 98 percent and 91 percent, respectively, of those given combination therapy. The majority of episodes of documented infection in both treatment groups necessitated additional antimicrobial treatment or other modifications of the initial regimen, as compared with only 22 percent of the episodes of unexplained fever. We conclude that initial single-agent therapy with certain beta-lactam antibiotics is a safe alternative to standard combination antibiotic therapy, although patients with documented infection or protracted neutropenia are likely to require additional or modified treatment.

Adolescent↗

Telling it to Studs Terkel: HMPRG at age five.

After five years, the Health and Medicine Policy Research Group, out of generosity or vain-glory, has come to believe that its health policy interventions are a moveable feast. In what follows, the nation's premier interviewer extracts from three HMPRG stalwarts the history and the style of work which, up to this moment, has proven remarkably productive for us. Please presume this interview is an invitation to readers wherever you may be to inquire and seek counsel about how what we have been able to do might be replicated in your city. The interview was aired on WFMT's Studs Terkel Program of January 6, 1986. Patricia Terrell, Executive Director of HMPRG, John McKnight, Professor of Urban Policy at Northwestern University and a co-founder of the group, and Quentin Young, former Medical Director of Cook County Hospital and President of HMPRG, answered, as best they could, Studs Terkel's interrogatories.

Chicago↗

New beta-lactam antibiotics in granulocytopenic patients. New options and new questions.

Infectious complications are a frequent cause of morbidity and, at many centers, the major cause of death in patients with cancer. The increased risk and severity of infectious sequelae result from profound alterations in normal host defenses that occur secondary to the underlying malignancy and the treatment thereof. During the last decade, early empiric antibiotic therapy has become standard practice in the initial management of febrile granulocytopenic patients and has contributed significantly to the improved outcome among patients undergoing cancer therapy. Although early death due to unsuspected or inadequately treated bacterial infection has been largely overcome, new problems--also with life-threatening implications--have emerged. As the use of cancer chemotherapy continues to increase, new populations of patients are being placed at increased risk of infection. Defining the host and environmental factors that contribute to this risk assumes central importance for delineating those patients who require the most intense surveillance. Changing medical practices (e.g., increased use of indwelling catheters) have contributed to the emergence of new pathogens. Recent drug developments (e.g., the third-generation cephalosporins and extended-spectrum penicillins) offer new treatment options, as well as generate controversy and confusion. For example, authorities disagree on the optimal duration and modifications in treatment that are required by cancer patients who remain granulocytopenic and who thus are at continued risk of multiple infectious episodes or superinfections. A question of current interest is whether combination therapy with synergistic agents is important in light of the development of the third-generation cephalosporins and extended-spectrum penicillins. Several of these new antibiotics have an exceedingly broad spectrum of activity that includes Pseudomonas aeruginosa, as well as Enterobacteriaceae, Serratia, Citrobacter, indole-positive Proteus, and anaerobes (including Bacteroides fragilis). However, the third-generation cephalosporins are not as active against staphylococci and streptococci as are the first-generation cephalosporins, and none is effective against enterococci. Nonetheless, these agents achieve serum levels that can be 10 to 100 times greater than the minimal inhibitory and bactericidal concentrations of gram-negative bacteria, raising the possibility that these drugs might be effective as single agents. The advantages of the third-generation cephalosporins are their minimal toxicity and long serum half-lives.(ABSTRACT TRUNCATED AT 400 WORDS)

Agranulocytosis↗

Calcium hydroxide pulpotomy for primary teeth: a clinical study.

Calcium hydroxide pulpotomies were performed in 17 carious primary mandibular molars. Variables in the pulpotomy procedure were recognized and controlled in an attempt to obtain a more favorable result or end product. The effects of two methods of hemorrhage control were also evaluated. The duration of treatment for the study ranged from three to nine months. Treatment was clinically successful for all 17 teeth. The radiographic evaluations were more favorable for the experimental group than for the control group. Treatment was radiographically successful for 15 teeth, questionable for one tooth, and unsuccessful for one other tooth. The results of this study suggest that the aluminum chloride-calcium hydroxide pulpotomy may be a viable alternative to formocresol pulpotomies in the primary dentition. Although these findings encourage continued research, including a long-term follow-up, a histologic study is indicated.

Aluminum↗

Genetics of Standardbred stallion reproductive performance.

Reproductive performance of 10 Standardbred stallions was related to the probability that the embryo resulting from a given mating would be heterozygous for transferrin or plasma esterase. Fertility, measured by foaling rate per insemination or by foaling rate per year, showed a highly significant regression on the probability of offspring heterozygosity for transferrin and, to lesser extent, for esterase. Substantial differences between stallions in the slope of the regression line and no deficiency of foals homozygous for either protein suggests that the relationship to fertility is indirect, probably a reflection of the amount of outcrossing between lines within the breed. An example of the potential impact of maximizing the probability of foal transferrin heterozygosity on the productivity of an actual farm is presented.

Animals↗

High dose flupenthixol decanoate in chronic schizophrenia.

In a double-blind trial, female 'drug-resistant' chronic schizophrenic in-patients were given high dose or standard dose flupenthixol decanoate for 13 weeks. Plasma flupenthixol levels showed a five-fold interindividual variation, but were consistently higher with the high dose. Analysis of final scores showed no statistically significant differences between groups with regards to mental state, ward behaviour and extrapyramidal side-effects. When compared with pre-trial scores, the extrapyramidal side-effects worsened significantly in the high dose patients and social withdrawal decreased in the standard dose patients. The mental state of a sub-group of patients, possibly drug resistant for pharmacokinetic reasons, improved significantly on the high dose over the 13 weeks.

Adult↗

Theme and variation in the development of the first transitional object.

In our research we have been attempting to elucidate the phenomenon we have labelled the 'first transitional object'. In this paper we have focused primarily on some dimensions along which the child can vary in his use of the first transitional object. We have pointed to the fact that some infants first come in contact with the 'blanket' at the age of three months, and this seems to be a critical time period for regular contact with the first transitional object. While there are variations in the child's attachment to the first transitional object from the very beginning, age two appears to be a crucial time when the intensity of the child's attachment to the 'blanket' becomes established. Most children seem to give up the first transitional object between five and six years of age, and an example of the disruption of this process was presented. An attempt was made to put these findings within a developmental context, while other variables which affect the fate of the first transitional object were also explored.

Age Factors↗

Impoverishment.

Explore the source record for details and available documents.

Culture↗

Arrhythmogenic right ventricular dysplasia: an uncommon cause of syncope in a young male.

Arrhythmogenic right ventricular dysplasia (ARVD) is a relatively rare disease first described in 1977. It is characterized by replacement of the right ventricle (RV) by fat or fibrous tissue. Patients often present with symptomatic ventricular tachycardia (VT) and the risk of sudden death is approximately 2.5% per year. Physical exam is often unremarkable. To date, the best diagnostic test is the MRI, however, electrocardiographic and echocardiographic data are useful. Treatment can be with beta blockers if a medical approach is desired. Multiple surgical options are available. No long-term studies are available to guide therapy; thus each case should be dealt with on its merits. This article describes the case of a 41-year-old male who had been asymptomatic until he presented with syncope. An extensive work up was undertaken and ARVD was diagnosed by MRI.

Adult↗

Directional coronary atherectomy in acute myocardial infarction.

Catheter-based intervention with directional coronary atherectomy (DCA) involving the surgical removal of obstructive plaque has been extensively studied in patients exhibiting stable and unstable angina. However, since no studies to date have evaluated the effectiveness of stand alone DCA as a primary treatment in the acute myocardial infarction (MI) setting, we conducted a five-year retrospective study of the early clinical and in-hospital outcomes of patients who underwent DCA within the 72-hour interval following acute MI. Our study included data obtained from a total of 30 acute MI patients treated between 1993 and 1998. Twenty-six of these patients (86%) met the criteria for angiographic success, while 11 (36%) showed less than 50% residual stenosis without the need for supplemental percutaneous transluminal coronary angioplasty (PTCA) or additional treatment for other major complications. Four (13%) of the patients exhibited negative outcomes including post-procedural MI, emergency coronary artery bypass grafting, abrupt vessel closure, hemorrhage necessitating vessel repair and transfusion, and death. Although stand alone DCA is not presently a common treatment, our results suggest it to be an effective and relatively safe procedure for acute MI. However, further studies involving a larger number of patients and a longer follow-up evaluation are needed for comparison of the relative effectiveness of this procedure with other treatments of acute MI.

Adult↗

The axiopulpal line angle and its relationship to fracture resistance of three dental alloy systems.

Under the circumstances of this experiment, the following conclusions may be drawn: The fine-cut alloy system (Velvalloy) has a higher resistance to fracture than the spherical alloy system (Spheraloy) or the dispersed-phase alloy system (Dispersalloy). The class II preparation for posterior teeth should contain a round axiopulpal line angle. Further studies to evaluate other modifications of preparation design are justified.

Chemical Phenomena↗