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T McLean

Publications and source records attributed to T McLean.

17 recordsLinked to original sources
PubMed2000

The relationship of symptoms and level of functioning in schizophrenia to general wellbeing and the Quality of Life Scale.

OBJECTIVE: Reports suggesting that quality of life in schizophrenia is more highly related to negative rather than positive symptoms are largely based on use of the Quality of Life Scale which was devised to assess deficit symptoms and does not include an assessment of subjective general wellbeing. In the current paper we examined symptoms, level of community functioning as well as living circumstances as correlates of Quality of Life Scale scores and scores on the General Well-Being Scale. METHOD: One hundred and twenty-eight patients completed the General Well-Being Scale and were rated on the Quality of Life Scale as well as scales assessing positive and negative symptoms. RESULTS: While negative symptoms, level of functioning and positive symptoms all were related to the scores on the Quality of Life Scale, General Well-Being Scale scores were primarily related to positive symptoms, particularly reality distortion. CONCLUSION: The results highlight the importance of recognizing the complex nature of the concept of quality of life. They demonstrate that varying indices of quality of life are likely to have different predictors.

Adolescent↗
PubMed1999

Exploring the longitudinal course of psychotic illness: a case-study approach.

OBJECTIVE: Thirty-three patients with a diagnosis of a psychotic disorder (schizophrenia, bipolar disorder, atypical psychosis) according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) were studied to qualitatively assess the longitudinal course of the disorder using a case-study approach. METHODS: Weekly fluctuations in patient symptomatology and overall social and personal functioning using the Global Assessment Scale were assessed following index hospitalization. Patients were followed for 1 year. RESULTS: The emergent courses showed no relationship to diagnosis but followed 3 general trends: 1) positive incline; 2) fluctuating; and 3) stable. Individual representations of each course were examined closely, and biological and psychosocial factors associated with each were evaluated. CONCLUSIONS: The results supported the longitudinal patterns and individual interactions of Strauss's Interactive Developmental Model. The clinical course of psychotic disorders may be represented by 3 patterns. Key factors in the interaction between patient and environment that generate important changes in the evolution of each illness were illustrated.

Adult↗
PubMed1996

Responses to moving small-field stimuli by the praying mantis, Sphodromantis lineola (Burmeister)

Adult, female praying mantises, Sphodromantis lineola (Burmeister), were presented with mechanically driven or computer generated stimuli in a series of seven experiments in order to test several hypotheses regarding visual prey recognition. When presented with a series of square black and white computer generated stimuli against a white background, mantises performed the highest rates of predatory behavior in response to those stimuli with a greater proportion of black versus white pixels (i.e., those that produced larger luminance decrements). Higher response rates to computer generated stimuli that produced larger luminance decrements were also seen when the stimuli were irregularly shaped or consisted of two small synchronized stimuli. Mantises responded characteristically to mechanically driven stimuli that were camouflaged to match the background against which they moved, preferring small (vs. large) squares and rectangles that were elongated parallel (vs. perpendicular) to their direction of movement. Finally, response rate to a small, preferred mechanically presented or computer generated stimulus was suppressed by a concurrent large-field stimulus in inverse proportion to the distance between the two stimuli. This phenomenon is characteristic of systems that include phasic lateral inhibitory circuits. All of these results are consistent with the existence of a movement detector visual sub-system, as found in other orthopteromorph insects such as acridid grasshoppers and cockroaches.

Animals↗
PubMed1995

Phosphorylation of Ser232 directly regulates the transcriptional activity of the P protein of human respiratory syncytial virus: phosphorylation of Ser237 may play an accessory role.

The phosphoprotein P of human respiratory syncytial virus (RSV) was expressed in eukaryotic cells in phosphorylated form. Site-directed mutagenesis of the recombinant protein established Ser232 as the major site of phosphorylation in vivo. Phosphorylation of bacterially made P protein in vitro by purified casein kinase II (CKII) resulted in the phosphorylation of Ser237, whereas mainly Ser232 was phosphorylated by a crude cell extract. The P kinase activity in the cell extract exhibited properties characteristic of CKII. While the Ser232,237 to Ala double mutant was nearly completely defective for phosphorylation and transcription, phosphorylation at Ser232, through the use of appropriate P mutant or kinase, activated P protein. Phosphorylation of Ser237 restored activity only to the extent it facilitated phosphorylation of Ser232. Phosphate groups of P protein in RSV-infected cells were highly stable; inhibitors of protein serine phosphatases had no effect on the intracellular turnover of the phosphates. Highly purified viral polymerase L was transcriptionally active but devoid of P protein kinase activity. Thus, CKII-mediated phosphorylation of Ser232 appears to be the primary regulator of P protein activity while phosphorylation of Ser237 may be involved in a modulatory role under certain conditions.

Binding Sites↗
PubMed1995

Induction by herpes simplex virus of free and heteromeric forms of E2F transcription factor.

We have determined that HSV causes rapid and large increases in cell-cycle-regulated free E2F and S-phase p107/E2F DNA binding activities in asynchronous cultures of C33A cells. Induction occurred by 4 hr postinfection and coincided with the appearance of viral encoded immediate-early and delayed-early proteins, i.e., when viral DNA replication normally commences. No increase in E2F activities occurred when cells were infected with viruses expressing mutant regulatory proteins ICP4 or ICP27, or mutant replication proteins ICP8, pol or helicase, or when cells were infected with wild-type virus in the presence of inhibitors of DNA synthesis. In contrast, ICP8 mutant-infected cells contained elevated amounts of NF kappa B activity equivalent to WT virus, no induction of Sp1 relative to WT virus, and reduced ATF/CREB activity relative to WT virus. Results of transient expression assays with E2F-responsive reporters indicated that the net effect of induction of both active (free E2F) and repressive (p107/E2F) complexes was a decrease in AdE2 promoter activity and an increase in c-myc promoter activity. Taken together these results suggest that HSV can cause unscheduled changes in the amount and functional status of a cell-cycle-regulated transcription factor. These results are discussed in light of possible roles for viral-induced alterations in E2F, especially as related to imposing or overriding cell-cycle checkpoints.

Activating Transcription Factor 1↗
PubMed1993

Evaluation of sputum smears concentrated by cytocentrifugation for detection of acid-fast bacilli.

Early identification and isolation of tuberculosis patients is of utmost importance to minimize the risk of further epidemic spread of the disease. The traditional concentrated acid-fast smears are not very reliable tools for the presumptive diagnosis of tuberculosis. Acid-fast bacillus (AFB) smears from 120 patients specimens and 80 simulated AFB samples were processed according to standard laboratory procedures and by cytocentrifugation (Cyto-Tek, Ames Division, Miles Laboratories, Inc., Elkhart, Ind.). Prior to dispensing of samples into the Cyto-Tek chambers, specimens were liquefied and decontaminated by mixture with an equal volume of 5% sodium hypochlorite (household bleach). Culture and smear results were correlated. Of 120 patient specimens, 43 were culture and smear negative by both methods. Ten specimens were overgrown with mold and bacteria, but 2 of them had positive AFB smears by cytocentrifugation only. There were 67 positive AFB cultures, with 67 positive cytocentrifuge smears and 34 positive smears by the conventional technique. Of the 80 simulated positive AFB samples, all grew mycobacteria on culture. Smears from the 10(5)- to 10(3)-CFU/ml specimens were positive by both methods. The simulated samples with 10(2) CFU/ml yielded smears positive only by cytocentrifugation. The Cyto-Tek AFB smears had a greater correlation with positive culture than did the smears from concentrated specimens. The sensitivity, efficiency, and rapidly of the Cyto-Tek AFB smear technique resulted in increased detection of mycobacteria in clinical specimens. The simplicity and safety of this method will enable qualified mycobacteriology technologists to rapidly and accurately perform sputum smears for AFB at clinics, emergency rooms, and field sites, as well as in the traditional laboratory setting.

Centrifugation↗
PubMed1988

Erythrocyte transit and neutrophil concentration in the dog lung.

We subdivided regional erythrocyte (RBC) transit time into the fraction spent in the large (greater than 50 microns), small (20-50 microns), and capillary (less than 20 microns) vessels of canine lungs. Using a combination of physiological and morphological techniques, the number of RBC and granulocytes in each vessel size was obtained by dividing the aggregate volume of the cell by the calculated volume of a single cell. The data show that the average transit time was 0.60 s in large vessels, 0.10 s in small vessels, and 1.37 s in capillary vessels and was longer (P less than 0.05) in the upper lung regions for small vessels and capillaries. RBCs pass through approximately 60 capillary segments at an average velocity of approximately 550 micron/s. Pulmonary hematocrit averaged 0.95 of the systemic hematocrit and was lower in capillaries than small vessels. PMN's were concentrated approximately 10-fold in the small vessels and 100-fold in the capillaries compared with peripheral blood. The multisegmented nature of the capillary bed allows this concentration because RBCs find pathways to stream around the slower moving PMNs.

Animals↗
PubMed1987

Ecology of dermatophyte infections in South Bronx, New York, 1969 to 1981.

This survey describes the ecology of superficial dermatophyte infections in South Bronx, New York from 1969 to 1981. The predominant species were Trichophyton rubrum (Castellani) Sabouraud, 1911 (57.5%), followed by Trichophyton tonsurans Malmsten, 1845 (18.5%), Trichophyton mentagrophytes (Robin) Blanchard, 1986 (11.5%), Microsporum canis Bodin var. canis Matsumoto, Padhye, and Ajello, 1902 (5%), Epidermophyton floccosum (Harz) Langeron and Milochevitch, 1930 (3.9%), and M. audouinii Gruby, 1843 (2.8%).

Arthrodermataceae↗
PubMed1986

Mycobacterium tuberculosis infection in the acquired immunodeficiency syndrome. A review of 14 patients.

The clinical findings in 13 drug abusers and one homosexual man with tuberculosis and the acquired immunodeficiency syndrome (AIDS) from New York City are described. Tuberculosis preceded the diagnosis of AIDS in nine of the 14 patients by a mean of 7 months and occurred within the same month in the remaining five. The presence of thrush, generalised lymphadenopathy, lymphopenia, cutaneous anergy and chest radiographs showing hilar adenopathy and/or lower lobe infiltrates was common among the patients in whom tuberculosis preceded AIDS. Eight of our patients had extra-pulmonary tuberculosis, six had disseminated tuberculosis and five had tuberculous lymphadenitis. Cultures of tissue biopsies may be positive for Mycobacterium tuberculosis despite the absence of acid fast bacilli or granulomas on microscopic examination. Tuberculosis generally responded to chemotherapy, but the majority of patients died from opportunist infections.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Histamine dose-response curves in guinea pigs.

Histamine dose-response curves were performed on anesthetized tracheostomized guinea pigs that were paralyzed and mechanically ventilated at a constant tidal volume and breathing frequency. The dose was calculated by generating an aerosol of known concentration and measuring the volume delivered to the lung. Increasing the dose was accomplished by increasing the number of breaths of aerosol delivered. The response to each dose was determined by measuring the change in airway resistance (RL) and dynamic compliance (Cdyn) using the method of Von Neergaard and Wirz (Z. Klin. Med. 105: 51-82, 1927). With increasing doses of histamine, RL increased and reached a plateau at approximately five times the base-line value and Cdyn fell to approximately 20% of its initial value. The variability in the base-line and maximum response as well as the calculated sensitivity and reactivity was less than that previously reported. Propranolol pretreatment increased resting RL and shifted the dose-response curve for RL to the left of the controls, increasing reactivity but not sensitivity. Atropine shifted the dose-response curve to the right of the control, decreasing sensitivity but without changing reactivity. The data for Cdyn showed that atropine pretreatment caused a higher resting value and propranolol pretreatment a lower value at the highest histamine dose but no differences in either sensitivity or reactivity.

Aerosols↗
PubMed1985

Regional differences in erythrocyte transit in normal lungs.

We measured regional blood volume and flow in the lungs of nine mongrel dogs. The time taken for the erythrocytes to transit through individual lung regions was calculated from the relationship t = V/Q, where V is blood volume and Q is flow. The data show that the total pulmonary blood volume was 82 +/- 6 ml and that the average time spent in the pulmonary vascular bed was 2.86 +/- 0.31 s. The frequency distribution of the transit times ranged from 0.41 to 6 s in the experiment with the shortest mean transit (1.62 s) and from 0.9 to greater than 20 s in the experiment with the longest mean transit time (4.6 s). The regional data show that the longer transit times were in the upper lung and that expansion of the blood volume as flow increased down the lung prevented an excessive shortening of the transit time. We conclude that increasing regional blood flow is associated with an expansion of regional blood volumes so that the transit times remain relatively constant.

Animals↗
PubMed1985

The effect of acute airway inflammation on bronchial reactivity in guinea pigs.

This study compared airways reactivity before and after an inflammatory response was induced in the airways by exposing them to cigarette smoke. Airways reactivity was measured to graded doses of histamine using a standard technique in 24 animals without drug pretreatment, in 17 pretreated with propranolol, in 17 pretreated with atropine, and in 18 pretreated with both atropine and propranolol. In each group, at least 5 animals not exposed to cigarette smoke served as controls, and the remaining animals were studied in groups of 4 or more at 30 min, 6, and 24 h after exposure to 100 puffs of whole cigarette smoke. The data show that airways reactivity was increased at 30 min but not at 6 and 24 h after exposure to cigarette smoke. Pretreatment with propranolol or the combination of propranolol and atropine prior to the histamine dose-response curve did not affect the increased response seen after cigarette smoke exposure, but pretreatment with atropine abolished it. Comparing this study with our previous histologic studies of the airways in similarly exposed animals, we conclude that the observed increase in airways reactivity occurs during the fluid exudative phase of the inflammatory response before the polymorphonuclear leukocytes migrate into the epithelium.

Acute Disease↗
PubMedDate not supplied

Exposures and expectations in the health care environment.

Airborne pathogens, bloodborne pathogens, and waste anesthetic gases all pose health risks to those in the PACU. The return of M. tuberculosis outbreaks to health facilities is an increasing problem. Guidelines for administrative procedures, and engineering and recipient controls must be enforced.

Air Microbiology↗