Biomedical subjects

M J Ault

Publications and source records attributed to M J Ault.

29 records · Page 2Linked to original sources

PubMed1989

Absence of hepatitis B surface antigenemia after vaccination.

Vaccination against hepatitis B is readily available and provides safe and effective immunization for individuals at increased risk for this disease. However, since the available vaccines employ a protein consisting of hepatitis B surface antigen, the question has arisen whether a detectable surface antigenemia might occur in recently vaccinated individuals. Employing two current immunoassays for hepatitis B surface antigen, we could not detect this marker in individuals either 1 hour or 24 hours after vaccination. We therefore conclude that the presence of surface antigen in the blood cannot be attributed to recent vaccination.

Hepatitis B↗

PubMed1988

Comparison of response prompting procedures in teaching numeral identification to autistic subjects.

This investigation compared the effectiveness and efficiency (sessions, trials, percentage of errors, direct instructional time through criterion, and incidental information learned) of constant time delay and system of least prompts in teaching students with autism to name numerals. Two sessions were provided each day; one with constant time delay and one with system of least prompts. Two students learned 16 numerals, and one student did not learn any numerals with these two procedures. The parallel treatments design was used to assess the effects of the two instructional strategies. The results indicate that both procedures were effective in raising responding to criterion levels for two subjects. The constant time-delay procedure was more efficient than the system of least prompts procedure in terms of sessions, trials, percentage of errors, and direct instructional time through criterion. No differences in efficiency were found for the measure of incidental information learned.

Association Learning↗

PubMed1988

Comparison of progressive and constant time-delay procedures in teaching community-sign word reading.

The effectiveness and efficiency of a progressive and constant time-delay procedure was compared. Three students with moderate mental retardation were taught to read 12 words commonly found on community signs. Six words were taught using a progressive time-delay procedure and six, using a constant time-delay procedure. The effectiveness of the two procedures was evaluated through the use of a parallel treatments design across sign words and replicated across subjects. Results show that both procedures were effective, with the constant time-delay procedure slightly more efficient in terms of number of minutes of direct instructional time and number of sessions to criterion. Both procedures generated error percentages of 1.4 or less. Findings were discussed in terms of selecting instructional strategies.

Attention↗

PubMed1985

Efficacy and safety of sublingual nifedipine in hypertensive emergencies.

Hypertensive emergencies are a diverse group of disorders characterized by a marked elevation of systemic arterial pressure that is associated with acute end-organ dysfunction. The efficacy and safety of sublingual nifedipine were evaluated in 16 men and 14 women (mean age 65 +/- 14 years) who had hypertensive emergencies. Before treatment, mean systolic blood pressure was 224 +/- 23 mm Hg, mean diastolic blood pressure was 125 +/- 18 mm Hg, and the average mean arterial pressure was 158 +/- 16 mm Hg. Administration of 10 or 20 mg of sublingual nifedipine initiated a smooth and predictable decline in blood pressure values within five minutes and produced a peak effect between 30 and 60 minutes. At 30 minutes, the decreases in the systolic blood pressure, diastolic blood pressure, and mean arterial pressure for the group were 49 +/- 24 mm Hg, 31 +/- 17 mm Hg, and 39 +/- 20 mm Hg, respectively, all of which were highly significant (p less than 0.001). By 60 minutes, nifedipine had decreased the diastolic blood pressure to less than 120 mm Hg in 97 percent of patients, less than 110 mm Hg in 93 percent, and less than 100 mm Hg in 67 percent. Fourteen patients required other antihypertensive medications within the first 12 hours for the antihypertensive effect to be maintained. In this group, the systolic, diastolic, and mean arterial pressures were significantly lower than baseline values (p less than 0.001) at the time that the other drugs were started (which occurred at a mean of 4.3 +/- 3.2 hours after entry into the study). The response to nifedipine correlated with the blood pressure value prior to treatment, but did not correlate with age, gender, value prior to treatment, but did not correlate with age, gender, or the type of hypertensive emergency. Twenty mg of nifedipine produced a significantly greater antihypertensive effect than did 10 mg during the first 20 minutes (176 +/- 15 mm Hg versus 201 +/- 18 mm Hg systolic; p = 0.009) and appeared to be more efficacious clinically. In only two of 30 patients (7 percent) was the blood pressure response considered inadequate, and all 10 patients with pulmonary edema or myocardial ischemia showed clinical improvement within 60 minutes of treatment. In one patient, flushing and another symptom suggestive of transient symptomatic hypotension developed after treatment with nifedipine. These results suggest that sublingual nifedipine is a safe, effective, and practical agent for treating patients with hypertensive emergencies.

Administration, Oral↗

PubMed1985

Pathophysiological events leading to the end-organ effects of acute hypertension.

The term "hypertensive crisis" refers to a group of acute hypertensive disorders that have, in common, evidence of end-organ dysfunction. From a pathophysiological viewpoint, these disorders may be classified into two major categories. In primary hypertensive disorders, the predominant pathophysiological events and subsequent end-organ failure are directly attributable to the uncontrolled hypertension. Secondary hypertensive crises have many similar features; however, the ultimate progression from onset of hypertension to end-organ failure tends to be modified by concurrent target-organ disease. The chain of events leading to the progression from benign to malignant hypertension centers around two general theories--the pressure hypothesis and the humoral hypothesis--both of which suggest that when a critical imbalance of pressure and/or humoral factors occurs, depending variously on etiological factors, rapidity, and degree and duration of blood pressure elevation, a series of pathological events ensue leading to myointimal proliferation and fibrinoid necrosis. The primary target-organ effects of severe hypertension generally affect the central nervous, renal, and cardiovascular systems and occur when the normal compensatory mechanisms are exceeded either by a breakthrough in autoregulation, as in the central nervous system, or by an imbalance in myocardial supply and demand. To a certain extent the pathophysiological events and target-organ susceptibility will determine the manner in which the hypertensive event presents. Although effective therapy is optimally tailored to the specific underlying disease process, in the acute setting, where important clinical data may be lacking, an appreciation of these underlying mechanisms will aid in the selection of a regimen that is both safe and effective.

Acute Disease↗

PubMed1985

Calcium-channel blockers in acute hypertension.

The acutely hypertensive patient may present with a broad spectrum of dysfunction. Given the wide variety of signs and symptoms, clinical settings, pathophysiological mechanisms, and type of end organ dysfunction, there is no ideal antihypertensive agent. In selecting an agent for treating such patients, the physician must consider efficacy in a variety of settings, rapidity of onset of action, duration of action, and ease of administration. In addition, one should keep in mind the risk of producing hypotension, the contraindication profile, the side-effect profile, and the cost and long-term usefulness of the agent. In this review, the calcium channel blockers verapamil and nifedipine are compared with drugs such as nitroprusside, diazoxide, hydralazine, labetalol, and clonidine. Verapamil, by intravenous administration, has a rapid onset of action, a reasonable duration of effect, a good side-effect profile, and appears to be useful on a long-term basis. Nifedipine, by oral or buccal administration, is useful in a variety of settings and had a rapid onset of action and reasonable duration of effect. In addition, nifedipine rarely causes hypotension, has minimal contraindications, an excellent side-effect profile, reasonable cost, and long-term utility. There is now extensive worldwide experience with verapamil and nifedipine in acute hypertension. They compare favorably with currently used agents.

Acute Disease↗

PubMed1982

Campylobacter enteritis: early diagnosis with Gram's stain.

Campylobacter jejuni has become one of the most important causes of infectious diarrhea in the United States. We examined the utility of Gram's stain of stool for the rapid presumptive diagnosis of Campylobacter enteritis in a large, urban hospital and found that this test has a sensitivity of 43.5% and a specificity of 99.4%. We believe that Gram's stain of stool could be used to direct the early management of up to one half of patients infected with this pathogen.

Adolescent↗

PubMed1982

Infection and diabetes: the case for glucose control.

This review summarizes data concerning the host resistance to infection in diabetes and the influence of an acute infection upon the endocrinologic-metabolite status of the diabetic patient. While it is well known that acute infections lead to difficulty in controlling blood sugar levels and the infection is the most frequently documented cause of ketoacidosis, controversy persists as to whether or not patients with diabetes mellitus are more susceptible to infection than age- and sex-matched nondiabetic control subjects. Our data obtained from the charts of 241 diabetic patients who were being followed as outpatients show a striking direct correlation between the overall prevalence of infection (p less than 0.001) and the mean plasma glucose levels (representing three or more fasting glucose determinations taken at times when no evidence of infection existed). There is a significant diminution in intracellular bactericidal activity of leukocytes with Staphylococcus aureus and Escherichia coli in subjects with poorly controlled diabetes in comparison with the control group. Serum opsonic activity for both Staph. Aureus and E. coli were significantly lower than in the control subjects. Taken together, the results from published reports as well as our data suggest to us that good control of blood sugar in diabetic patients is a desirable goal in the prevention of certain infections (Candida vaginitis, for example) and to ensure maintenance of normal host defense mechanisms that determine resistance and response to infection.

Antibody Formation↗

PubMedDate not supplied

Community-acquired bacterial pneumonias in homosexual men: presumptive evidence for a defect in host resistance.

Over a three year period, we encountered seven homosexual men who developed pneumonias due to S. pneumoniae or H. influenzae in the absence of apparent risk factors. When compared to heterosexual controls, the homosexual group had a much higher frequency of bacteremia, complicated primary infections, multilobar involvement, required longer antibiotic therapy, and took longer to defervesce. Three of our seven homosexual patients fulfilled criteria for the acquired immunodeficiency syndrome (AIDS); two of the others had generalized lymphadenopathy and the other two likely AIDS-related abnormalities. Overall they presented with a spectrum of clinical findings. Two of the patients developed other opportunistic infections associated with AIDS. Since recovery from these pyogenic pneumonias requires an appropriate antibody response, our patients may have had a defect in B-cell function. Moreover, these observations suggest that functional B-cell abnormalities may occur in AIDS and syndromes premonitory of AIDS.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

Peripherally inserted central catheters in the intensive care unit.

We report the success rate and complications of peripherally inserted central catheters (PICCs) in patients hospitalized in an intensive care unit (ICU). We performed a cohort study in the ICU of a large tertiary care, university-affiliated community hospital. All ICU patients for whom their attending physicians requested a PICC service consultation were included. Main outcome measurements included (1) the success rate for initial PICC placement, (2) the placement complication rate, and (3) the overall success and complication rate. Of the 91 consecutive attempts at PICC placement, 89 (97.8%) were successful: of the 89 successful placements, 25 (28%) required cutdown procedures. There were 20 complications of initial placement and 8 delayed complications, which occurred in 19 PICCs. Complications included recatheterization after first attempt was unsuccessful (10), catheter malposition (7), palpitations or catheter clotting (3 each), heavy bleeding or mechanical phlebitis (2 each), and arterial puncture (1). The overall success rate for completion of therapy using the PICC was 74.7%. The most frequent reasons for failure to complete therapy were catheter dislodgment in 8 patients and "infection" in 9 patients. Of these 9 patients with "infections," 8 catheters were discontinued due to potential infection, and only 1 was removed due to confirmed infection. The confirmed infection rate was 6/10,000 patient days. The PICC appears to be a reasonable alternative to other approaches to peripheral and central venous access. The initial and overall success rates from this preliminary study justify further evaluation of the PICC in critically ill patients.

Adolescent↗

PubMedDate not supplied

The stuck catheter: a case report.

Complications after the use of central venous catheters have become more frequent as their use in therapy has increased. As a result, the recognition and management of central venous catheters must be emphasized. We describe a unique problem, that of the "stuck catheter," and its safe and simple solution.

Adult↗