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Biomedical subjects

D J Wilson

Publications and source records attributed to D J Wilson.

At least 253 records · Page 14Linked to original sources
PubMed1983

Intravenous labetalol in the treatment of severe hypertension and hypertensive emergencies.

The antihypertensive effects of intravenous labetalol were evaluated in 59 patients with hypertensive crises or severe hypertension in need of rapid lowering of blood pressure in a multicenter study. Patients appearing with a supine diastolic blood pressure 125 mm Hg or greater, or a supine systolic blood pressure of more than 200 mm Hg received an initial mini-bolus injection (20 mg) of labetalol. This was followed by repeated incremental doses of 20 to 80 mg given at 10 minute intervals to achieve a supine diastolic blood pressure of less than 95 mm Hg or decrease 30 mm Hg or greater, or a satisfactory decrease in systolic blood pressure. Patients were stratified into those who had taken antihypertensive medication within 24 hours and those who had not. The initial mini-bolus injection caused rapid but not abrupt reduction in blood pressure; the baseline mean blood pressure decreased 23/14 mm Hg. Further injections were needed in the majority of patients (mean: 197 mg). The blood pressure reduction after the last dose of labetalol was 55/33 mm Hg. In pretreated patients and in those who had no medication for 24 hours prior to the intravenous labetalol, the response was similar. Heart rate decreased 10 beats per minute in the total population. In patients pretreated with beta-adrenergic blockers, blood pressure response was similar to that in the total group (59/35 versus 55/33 mm Hg), but heart rate remained essentially unchanged. The dose required to achieve the therapeutic effect was less in pretreated patients than in untreated patients, but the duration of action was shorter. No serious adverse effects were encountered even in patients with concomitant diagnoses of acute left ventricular failure, myocardial infarction, stable congestive heart failure, atrial fibrillation, angina pectoris, acute stroke, transient ischemic attack or encephalopathy. Labetalol is a safe and effective treatment for a rapid blood pressure reduction in hypertensive emergencies.

Adrenergic beta-Antagonists↗
PubMed1983

Lymphokine-activated killer cell phenomenon. III. Evidence that IL-2 is sufficient for direct activation of peripheral blood lymphocytes into lymphokine-activated killer cells.

Purified interleukin 2 (IL-2) was found to be sufficient for direct activation of peripheral blood lymphocytes into lymphokine-activated killer (LAK) cells. The LAK activation factor was directly and consistently associated with IL-2 activity using classic protein purification techniques, adsorption to IL-2-dependent cell lines, and inhibition with anti-Tac antibody. As yet, no other cytokines have been found that perform the same role.

Antibodies, Monoclonal↗
PubMed1983

Lymphokine-activated killer cell phenomenon. II. Precursor phenotype is serologically distinct from peripheral T lymphocytes, memory cytotoxic thymus-derived lymphocytes, and natural killer cells.

Culture of human peripheral blood lymphocytes (PBL) in partially purified and lectin-free interleukin 2 results in the generation of cytotoxic effector cells which have the unique property of lysing natural killer (NK)-resistant fresh human tumor cells. We have termed these effector cells "lymphokine- activated killer" cells (LAK). LAK are generated from both normal and cancer patients' PBL and are able to lyse both autologous and allogeneic tumor cells from all histologic tumor types tested. Our previous studies suggested that the LAK phenomenon was distinct from either the cytotoxic thymus-derived lymphocyte (CTL) or NK systems based on a variety of criteria. This study reports that the cell type involved is also distinct, as determined by phenotypic characteristics. The LAK effector cell phenotype was analyzed in parallel with alloimmune CTL, and LAK were found to be similarly susceptible to the monoclonal anti-T cell antibodies OKT-3 or OKT-8 plus complement. In contrast the LAK precursor was not susceptible to the OKT-3 or Leu-1 antibodies plus complement, while the ability to generate alloimmune CTL was totally obliterated when tested using the same PBL responder population; in fact, generation of LAK was found to be augmented five- to sixfold, clearly suggesting that LAK precursor cells are not T lymphocytes as defined by these antibodies. LAK precursors were found to be abundant in NK cell-enriched Percoll gradient fractions, which had been depleted of the 29 degrees C E- rosetting "high affinity" T cells. However, LAK precursors were found to be distinct from the majority of NK cells since lysis of fresh PBL with the monoclonal antibodies OKM-1, Leu-7, or OKT-11 significantly depleted or totally eliminated NK activity, while subsequent activation of the remaining cells generated high levels of LAK and in some cases augmented levels of LAK. LAK precursors were found to be distributed in the thymus, bone marrow, spleen, lymph node, and thoracic duct in addition to the PBL. Therefore, while the cell(s) responsible for activation and expression of LAK activity have some common features with the classic T cell-mediated CTL and NK cell systems, the LAK precursor cells are clearly distinct as determined by phenotype analysis using monoclonal antibodies and complement, and at present must be classified as a "null" cell.

Animals↗
PubMed1983

Extent of BrdUrd-induced prolactin gene amplification in GH cells.

The thymidine analog, 5-bromodeoxyuridine (BrdUrd), induces prolactin (Prl) synthesis and Prl gene amplification in a subclone of GH cells (rat pituitary tumor cells in culture). Withdrawal of drug treatment reverses both processes. Our previous results show that Prl gene amplification is associated with an event involving extrachromosomal DNA. The results presented in this report show that a 20-kb length of DNA, including all the coding sequences of the Prl gene, is amplified following BrdUrd treatment of this strain of GH cells. Amplification of DNA sequences extends about 3 kb upstream from the 5' end and about 7 kb downstream from the 3' end of the Prl gene. The DNA sequences immediately adjacent to these 5'-and 3'-flanking regions of the Prl gene are not affected by BrdUrd treatment. These results suggest that BrdUrd-induced amplification of Prl gene coding and neighboring sequences is restricted to within 3 kb of the 5' end and within 7 kb of the 3' end of the structural gene Analysis of low-molecular-weight extrachromosomal DNA isolated by Hirt's procedure from drug-treated cells reveals a similar pattern of amplification of the Prl gene and its flanking sequences.

Animals↗
PubMed1983

Comparison of growth of Mycoplasma pneumoniae on modified New York City and Hayflick media.

Modified New York City medium was compared to Hayflick solid medium without methylene blue, using 23 stock strains of Mycoplasma pneumoniae. Time to recovery was the same for both media, never longer than 24 hours. Sensitivity, as measured by colony counts, was significantly greater with Hayflick medium. Modified New York City medium may not be more rapid than Hayflick medium and may not offer significant advantages over the latter.

Culture Media↗
PubMed1983

Detection of chlamydial cervicitis by Papanicolaou stained smears and culture.

The ability of the cervical Papanicolaou (Pap) smear to detect cervicitis associated with Chlamydia trachomatis was investigated. Cultures and cervical cytology samples were obtained from 487 women seen at the Mayo Clinic Department of Obstetrics and Gynecology and at the Sexually Transmitted Disease clinic of the Olmsted County Health Department. Adequate pap smears contained endocervical or metaplastic cells. Thirty-seven patients had positive Chlamydia cultures; of these, 14 were cytologically suggestive of Chlamydia, 10 were negative but satisfactory, and 13 were unsatisfactory. Of the 450 patients with negative cultures, 21 had cytologic findings suggesting infection. Thus, of 35 cases suggestive cytologically, 14 (40%) were confirmed by culture. Of the 21 false-positive cytologies, eight were in postpartum women. Because of problems with specificity and inadequate smears, cervical cytology specimens should not replace culture as a means of detection, but can identify women who should be cultured for C. trachomatis.

Cells, Cultured↗
PubMed1982

Prevalence of antibody to Chlamydia in renal transplant recipients and other population groups.

The serologic response to Chlamydia was determined with three sequential serum specimens from 25 renal transplant recipients (RTR) and from 25 blood donors who were matched for age and sex with the study group. Antibodies to Chlamydia were also measured in serum specimens from several other populations. The geometric mean titers (GMT) were significantly higher (P less than 0.05) for infants with pneumonia (1:6927) and women attending a sexually transmitted disease (STD) clinic (1:35) compared with pregnant women (1:25), normal infants, less than 23 weeks of age (1:11), and RTR (1:13). Titer increases of greater than or equal to fourfold were detected in 4 of 25 (16%) RTR, but could not be correlated with clinical pneumonia. Because of the high background prevalence (20% in RTR, 80% in STD patients), combined with low GMT of chlamydial antibody in these groups, the serologic diagnosis of respiratory tract infections in immunosuppressed adults required serial serum specimens.

Adult↗
PubMed1981

Vitreous fluorophotometry: identification of sources of variability.

Slit-lamp vitreous fluorophotometry (VF) has been used by several investigators to document the early breakdown of the blood-ocular barrier. After an injection of fluorescein, levels of fluorescein in the vitreous humor are reported to be elevated in diabetic patients compared with controls even when there is no retinal pathologic condition discernible by angiography or ophthalmoscopy. We have examined the technique of VF in normal persons and have identified several potential sources of error in the determination of vitreous fluorescein levels. Fluorescein in the choroidal circulation significantly influences VF readings taken at the retinal surface and in the posterior vitreous. This effect is modulated by ocular pigmentation, with heavy pigmentation of dark-eyed normals more effectively screening out choroidal fluorescence than the light pigmentation of blue-eyed subjects. Influence of choroidal fluorescein extends toward the midvitreous, and the range of influence is directly related to the slit width of the exciting light. At narrow slit widths the effect is diminished but can never be completely eliminated. Blood fluorescein levels decrease with time, and since choroidal fluorescein contributes to VF values, the time after injection that VF reading are taken is a critical parameter.

Adult↗
PubMed1981

Control of severe hypertension with pulse diazoxide.

Immediate or rapid reduction in blood pressure may be indicated in the management of hypertensive emergencies in patients with recognized cardiovascular or cerebrovascular disease. Our study has shown that pulse administration of diazoxide is effective in reducing blood pressure in these patients with severe, uncontrolled hypertension. Blood pressure reduction was gradual and could be titrated with repeated pulses of 50 or 75 mg of diazoxide. Pulse administration of diazoxide may represent the preferred method of administration in most patients when this potent antipressor agent is indicated. Our experience suggests that pulse diazoxide appears to be a suitable alternative to other parenteral antihypertensive agents and provides a gradual reduction of blood pressure in high-risk patients with severe, uncontrolled hypertension. The procedure carries a minimum risk of serious cardiovascular sequelae.

Adult↗
PubMed1980

Ingestion of formic acid-containing agents--report of three fatal cases.

Three patients were treated after they had deliberately ingested domestic agents containing formic acid. The major complications included the local effects on the oropharynx, oesophagus and stomach, metabolic acidosis, derangement of clotting mechanisms with haemorrhage and shock, widespread intravascular haemolysis, disseminated intravascular coagulation and the acute onset of respiratory and renal failure. All 3 patients died between 2 and 14 days after admission. It is the authors' belief that intensive therapy from the outset to include exchange transfusion, infusion of clotting factors, high dose steroids, ventilatory support and peritoneal or haemodialysis with parenteral nutrition may perhaps offer a better chance for survival.

Adult↗
PubMed1976

DDT levels in milk of rural indigent blacks.

Human milk samples from low-income blacks residing in rural Mississippi and Arkansas and middle-class whites residing in metropolitan Nashville, Tenn, were analyzed for concentrations of DDT and its metabolites. The mean total DDT concentration (DDE [derivative of DDT]+DDT) of 38 samples from the blacks was 447 parts per billion (ppb); the range was 59 to 1,900 ppb. The mean of the 14 samples from Nashville residents was 75 ppb (range, 15 to 133 ppb). The difference in the DDT concentrations in the two populations indicates that rural low-income blacks are still highly contaminated with pesticides, even though the general use of DDT has been banned. Due to the limited amount of information from the donors, no correlation could be made between the DDT concentration and diet, age of child, home pesticide use, or distance of residence from farming fields.

Black or African American↗
PubMed1976

Determination of nicotine concentrations in human milk.

A total of 34 samples of human milk from 15 donors was analyzed for nicotine content, using a new method of sample preparation and subsequent quantification by gas chromatography. Nicotine was not found in the six samples of milk from non-smokers. The 28 samples from smokers contained an average of 91 parts per billion (ppb) nicotine (ranging from less than 20 ppb to 512 ppb). While no adverse effects to the infant due to nicotine in human milk have been documented, this method of analysis will allow systematic monitoring of nicotine concentrations in the milk of lactating women. These results should not be used to deter breast-feeding; rather, they offer another reason for mothers to reduce or cease smoking.

Breast Feeding↗
PubMed1975

Lead levels in human deciduous teeth in Tennessee.

Deciduous teeth were analyzed by atomic absorption spectroscopy for lead content to ascertain the extent of lead exposure in certain areas in Tennessee. The data were analyzed to clarify the relationships between tooth lead content and race, sex, age, tooth type, economic status, and place of residence. Results indicated that blacks had slightly higher lead concentrations than whites; however, the age and sex of the person or the type of tooth analyzed had little effect upon the lead content. The major factors were shown to be economic status and, indirectly, place of residence.

Black or African American↗