Rapid liquid chromatography/tandem mass spectrometer (LCMS) method for clozapine and its metabolite N-desmethyl clozapine (norclozapine) in human serum.

Clozapine is indicated for the treatment of schizophrenia and related psychotic disorders. Several methods have been developed for monitoring Clozapine levels; however, they possess limited specificity and are often laborious. This study describes a simple liquid chromatography/tandem mass spectrometer (LCMS) method in human serum. The ion transitions monitored were m/z 327, 270, 296 for Clozapine, m/z 313, 192, 227 for Norclozapine and m/z 328, 271 for Loxapine. The assay is linear (25-1000 ng/ml) and showed a good correlation (r=0.98) within the analytical range of 79-1210 ng/ml in human serum. This assay is highly specific and sensitive for the simultaneous measurements of Clozapine and Norclozapine. The simplification of this assay makes it ideal for high throughput analyses of the patient samples in a routine clinical laboratory staffed with general medical technologists.

Tumor growth and tumor radiosensitivity in mice given myeloprotective doses of fibroblast growth factors.

BACKGROUND: Radiation at doses high enough to cure cancer also frequently destroys normal tissue. Development of agents that protect normal tissue without also protecting diseased tissue has been difficult. In vivo radioprotection of bone marrow by acidic and basic fibroblast growth factors (FGF1 and FGF2, respectively) has recently been demonstrated after whole-body irradiation of C3H/HeN mice. PURPOSE: Our purpose was to determine whether myeloprotective doses of those growth factors also protect malignant tumors. METHODS: First, we investigated the effects of exogenous FGF1 or FGF2 (FGF1/2) administration (treatment group receiving two intravenous injections of 3 micrograms FGF1/2 per mouse 24 hours and 4 hours before local irradiation of right hind leg and control group receiving two intravenous injections of 0.1 mL of saline) on growth and radiosensitivity of three transplantable murine tumors (one squamous cell carcinoma [SCC-VII] and two sarcomas [KHT and Rif-1]), all of which were grown in C3H/HeN mice. We then evaluated the effect of FGF1/2 on tumor cell proliferation, cell cycle distribution, and pulmonary metastatic frequency in the mice. Specifically, survival studies were performed in mice treated with 0, 6, 6.5, 7.5, 8.5, 9, or 10 Gy whole-body irradiation with or without FGF2 (n = 250). Rif-1 (n = 40), KHT (n = 40), and SCC-VII (n = 40) tumors were implanted in the hind leg of mice, and mice were treated with FGF2 or saline when their tumor-bearing thighs were 9 mm in diameter. In separate experiments (treatment group receiving two injections of 3 micrograms each of FGF2 [6 micrograms total] either intravenously or intratumorally 24 hours and 4 hours before local tumor irradiation and control group receiving 0.1 mL saline), tumor growth was followed, and mice were killed to count lung metastases and measure tumor proliferating cell nuclear antigen (PCNA) and bromodeoxyuridine labeling at various times thereafter (three to eight mice per group). Tumor growth curves of untreated and irradiated tumors were determined with and without intravenous or intratumoral FGF1/2 in SCC-VII tumors (n = 120). Radiation doses to the tumor-bearing leg were 15 and 30 Gy for SCC-VII, 30 Gy for Rif-1, and 15 Gy for KHT. From each experiment, the mean (+/- 1 standard error) was calculated from data obtained from three to 20 mice. Statistical tests used included two-tailed Student's t test, the chi-squared test, and Fisher's exact test. All P values represent two-tailed tests of statistical significance. RESULTS: There was no statistically significant difference in tumor growth rate between FGF2-treated and saline-treated mice when FGF2 was administered intravenously at doses and schedules found to be optimally myeloprotective in whole-body irradiation experiments. Intravenous administration of FGF2 did not induce lung metastases, and it did not augment the S-phase fraction of tumor cells. Likewise, there was no evidence of enhanced cell proliferation as measured by PCNA-labeling index. Intratumoral injection of FGF1/2 did increase the size of SCC-VII tumors (P < .05 [Student's t test] at 3 days after treatment); however, the radiation response after intratumoral injection of growth factor was not compromised. CONCLUSION: Low intravenous doses of FGF1 or FGF2 appear to protect bone marrow from the toxic effects of radiation without increasing the rates of tumor growth or metastases or decreasing the radiosensitivity of tumors.

Management of pediatric postoperative chylothorax.

Questions persist about the management of postoperative chylothorax in infants and children. Our experience with postoperative chylothorax over the most recent decade (1980 to 1990) has been reviewed. The type and amount of drainage, data from cardiac catheterization and echocardiography, operative decisions and details, and eventual outcomes have been cataloged. All patients were initially treated with total gut rest, with operation reserved for unabated drainage. Chylothorax developed postoperatively in 15 infants and 11 children (18 with a cardiac procedure and 8 with a noncardiac procedure). The average age was 3.1 years. Spontaneous cessation and cure occurred in 19 (73.1%) of these 26 patients, with an average drainage duration of 11.9 days (range, 4 to 30 days). Those for whom operation was chosen drained preoperatively for an average of 29.2 days (range, 25 to 40 days). There were no deaths in either group. Complications were lymphopenia (2 patients) and fungal sepsis (1 patient). The amount of drainage per day was not significantly different between patients treated operatively and those treated nonoperatively. Failure of nonoperative management was associated with venous hypertension from increased right-sided cardiac pressures or central venous thrombosis (p < 0.05, Fisher's exact test). Presumably this increased pressure is transmitted to the lymphatic system. These patients should be identified early and considered for thoracic duct suture or pleuroperitoneal shunting.

The menstrual cycle and punitiveness.

Subjects (n = 59) read vignettes of seven different college disciplinary cases and for each one selected a level of punishment. Three groups of subjects consisted of women in the menstrual (n = 12), premenstrual (n = 10), and intermenstrual (n = 13) phases. In addition, there were conditions in which women who were approaching the premenstrual phase were led to believe they were in it (n = 7) or were still several days away from it (n = 7). Finally, there was sixth group: males of comparable age and background (n = 10). The six groups were responsive-and about equally so-to differences among the seven cases. However, the groups did not differ in average level of punishment selected nor did they differ in reliability of judgment across individuals. There was some indication that males and the women led to believe they were premenstrual, found the task to be harder than did the other groups.

Polymorphic forms of Lp(a) with different structural and functional properties: cold-induced self-association and binding to fibrin and lysine-Sepharose.

Two different Lp(a) polymorphs were isolated from the same individual and shown to have important differences both in their solution properties and in interaction with lysine Sepharose and fibrin. One Lp(a) particle (d-Lp(a)) with a large apo(a) isoform had a density of 1.087 g/ml and a molecular weight of 3.17 million, while the other Lp(a) particle with a small apo(a) isoform having a mobility faster than that of apoB was larger and had a molecular weight of 3.75 million and a density of 1.054 g/ml. D-Lp(a) underwent cold-induced self-association and also had a higher affinity for lysine Sepharose, whereas the other Lp(a) polymorph did not. Both Lp(a) particles bound fibrin via two different binding sites, one of which involved fibrin lysine residues which are also recognized by plasminogen. Lysine-mediated binding of d-Lp(a) by fibrin was ten times stronger than that of the other Lp(a) particle, whereas non-lysine-mediated binding of either Lp(a) species by fibrin was of equal strength. At saturation, 80% of d-Lp(a) bound fibrin at sites that did not involve lysine residues, whereas only 33% of the other Lp(a) polymorph bound to these sites. These findings indicate that the binding of Lp(a) to fibrin is more complex than previously thought and imposes another layer of difficulty on our understanding of how Lp(a) regulates and/or impairs fibrinolysis.

Egotism and attribution.

Egotism is defined as the tendency to make attributions that put oneself in the best possible light, for example, the attribution of good outcomes to one's skill rather than to luck. An experiment was designed to demonstrate egotism. To rule out alternative explanations, the experiment compared the attributions of actors and observers for both good and bad outcomes. Theoretical considerations suggested that egotism might be especially likely at the conclusion of competition. Hence, subjects competed, won, or lost and then made attributions for their own and their opponents' outcomes. Evidence for egotism was clear. In addition, subjects made predictions of their opponents' attributions, which often turned out to be fairly accurate.

Avoidance of the handicapped: an attributional ambiguity analysis.

We demonstrated a general strategy for detecting motives that people wish to conceal. The strategy consists of having people choose between two alternatives, one of which happens to satisfy the motive. By counterbalancing which one does so, it is possible to distill the motive by examining the pattern of choices that people make. The motive used in the demonstration is the desire we believe most people have to avoid the physically handicapped. Because they do not wish to reveal this desire, we predicted that they would be more likely to act on it if they could appear to choose on some other basis. In two studies we found that people avoided the handicapped more often if the decision to do so was also a decision between two movies and avoidance of the handicapped could masquerade as a movie preference.

Obtaining reliable plasma sodium and glucose determinations from pulmonary artery catheters.

In critically ill patients, blood specimens are frequently withdrawn from intravascular catheters without consideration of possible infusate contamination, of test accuracy, or of undue blood loss. The reliability of sodium (Na+) and glucose determinations withdrawn from the venous infusion port of a pulmonary artery catheter was studied in 30 patients after cardiac surgery. Catheter patency was maintained by a saline and heparin infusate. Venipuncture samples for Na+ and glucose served as controls. A sample containing the dwell volume of the catheter and the stopcock (1 ml) was withdrawn and discarded, followed by fifteen 1 ml samples being taken for analysis. It was concluded that Na+ values are stable after discard of the catheter dwell volume and an additional milliliter of blood. Minimal clinical differences were found in the glucose values after discard of the catheter dwell volume and two additional milliliters of blood.

Sensitivity of swine buffy coat culture to infection with hog cholera virus.

The susceptibility of swine buffy coat (BC) cultures inoculated with hog cholera (HC) virus in the presence of homologous antiserum was greater than that of a pig kidney (PK-15) cell line similarly inoculated. The virus was isolated from BC cultures grown in the presence of 0.1% hyperimmune serum, whereas it could not be consistently recovered from the PK-15 cell line in which hyperimmune serum concentrations exceeded 0.025%. Maximal viral titers in BC culture were reached between postinoculation days 4 and 8. Peak titers were not influenced by the age of cells at infection or dose of virus. Data were present in support of the hypothesis that the decrease of HC viral isolations in BC cultures from HC epizootics was related to lessened use of attenuated vaccines.

Persistent hog cholera infection detected during virulence typing of 135 field isolates.

During the hog cholera (HC) eradication program in the United States, 135 field isolates were characterized by inoculation into specific-pathogen-free pigs. This gave origin to the classification of 61 (45%) as high virulent, 37 (27%) as low virulent, 29 (22%) as avirulent or immunizing, and 8 (6%) as capable of causing persistent infection. The persistent infections caused by the eight isolates were of long durtion, lasting in one instance to 152 days. The persistently infected pigs remained relatively free of clinical signs of HC but had high concentrations of HC virus (HCV) in their blood. When 6 of these pigs were given a second inoculation (with the virulent Ames strain of HCV), 2 died while the health status of 4 remained unchanged.

Bovine viral diarrhea infection in pregnant swine.

Twenty pregnant gilts (5 groups of 4) were infected experimentally with 1 of 4 strains of bovine viral diarrhea virus (BVDV) administered intranasally-orally. Blood specimens were taken from the gilts on postinfection day (PID) 7 and cultured for virus. Serum specimens, obtained on PID 21 and at termination of the experiment, were tested for neutralizing antibodies. At 90 to 112 days of gestation, the gilts were euthanatized and their fetuses were examined for evidence of intrauterine infection. Evidence of infection was demonstrated in all of the gilts, either by isolation of BVDV at PID 7 or subsequently by detection of neutralizing antibody titers. Intrauterine infection was confirmed in one of 20 gilts by isolation of BVDV, detection of neutralizing antibodies, and demonstration of microscopic lesions in the fetuses. The microscopic lesions were characterized as nonsuppurative meningitis and choroiditis. Clinical signs of disease were not seen in the infected fetuses. Of 8 gilts exposed to strains of BVDV pathogenic for cattle, 1 gilt developed intrauterine infection, 2 gilts were found barren, and 3 gilts had significantly fewer fetuses than copora lutea.

Swine buffy coat culture: an aid to the laboratory diagnosis of hog cholera.

A 2-step technique for the isolation of hog cholera (HC) virus consisting of an initial culture on buffy coat (BC) cultures and subinoculation to a pig kidney cell line (PK-15) was described. By this technique, HC virus was confirmed in specimens from 65 herds in which the conventional cell culture isolation technique failed. The herds were located in 20 states and Puerto Rico. Specimens from 29 of the 65 herds were inoculated into specific-pathogen-free (SPF) pigs. Hog cholera virus was recovered from 27 of the test pigs. The 2 pigs from which virus was not recovered had signs of acute infection and, on necropsy, had gross lesions of HC infection.

End-point dilution-fluorescent antibody technique for cloning hog cholera virus.

Hog cholera virus was cloned by incubating selected pretitrated dilutions of the virus on PK-15 cell cultures for 2 hours. After a thorough washing, the coverslip cell cultures were overlaid with medium containing 0.1% hog cholera immune serum to prevent secondary foci. Forty-eight hours later, the cultures were vigorously washed and maintenance medium containing 5% bovine fetal serum was added. When examined by the fluorescent antibody technique 18 hours later, single plaques were observed in some cultures with no evidence of secondary foci. The virus clone subsequently yielded a homogeneous population of hog cholera virus that retained the characteristics of the parent strain; pathogenicity of the virus clone in pigs was demonstrated, and specific immunofluorescence occurred in infected cell cultures stained with fluorescein isothiocyanate-labeled antibody. The method used gave reasonable assurance of the cloned virus' freedom from extraneous agents.

Field evaluation of enzyme-linked immunosorbent assay for detection of antibody to African swine fever virus.

The enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to African swine fever virus was evaluated under field conditions in the Dominican Republic. A total of 3,402 swine serums were tested by ELISA. All ELISA-positive serums (n = 224) and 426 of 2,760 ELISA-negative serums were retested by indirect immunofluorescence (IIF). There were no antibodies to ASF virus detected by IIF in ELISA-negative serums. By IIF, antibodies were detected in only a small portion of the ELISA-positive serums. The specificity and sensitivity of ELISA and IIF were investigated and discussed. It appears that poor quality serums had an effect in ELISA results. Detection of immunoglobulin (Ig) G and IgM classes of antibodies in the ELISA and IIF-positive serums were also performed and related to longevity of African swine fever virus infection. The ELISA is recommended as an efficient method in testing large number of serums; positive results are to be retested by IIF.

Thermal inactivation of hog cholera virus in ham.

Experiments were conducted to determine the temperatures required to inactivate hog cholera virus (HCV) in fresh ham after 1 minute and in cured and processed (canned) ham after 90 minutes. A momentary or "flash" temperature of 71 C for 1 minute caused inactivation of the virus in 15 of 15 cubes (2 cm3) of ham. Hog cholera virus was destroyed in 21 of 21 canned hams (weighing 0.91 kg each) when an internal temperature of 65 C was sustained for 90 minutes. Pigs were found to be more sensitive than tissue culture cells for detecting viable HCV in heat-processed fresh hams. Virus was isolated by tissue culture technique only from those hams exposed to temperatures below 61 C. The relative concentration of HCV in unheated cured hams of experimentally infected pigs varied over a wide range; these pigs were inoculated with the virulent Ames strain and were killed on postinfection day 6 or 7.

Transmission of hog hog cholera virus by mosquitoes.

Mosquitoes trapped during an epizootic of hog cholera (HC) in Maryland in 1969 were prepared into 40 pools which were inoculated in pigs. Hog cholera virus was confirmed in pigs inoculated with 8 of 40 pools of mosquitoes. Generally, the pigs contracting HC developed chronic infections with persistent viremia that lasted 30 or more days. Two pigs seemed healthy when euthatized 62 and 80 days after inoculation, yet viremia of high titer was detected in each. Experimental studies were performed with 2 laboratory strains of mosquitoes, Aedes aegypti and Culex tarsalis, to determine if biological and mechanical transmission occur. Biological transmission was not confirmed, but HC virus was retained in A aegypti for 3 days. Mechanical transmission was confirmed with A aegypti in 2 of 9 experiments.

Natural infection of pigs with bovine viral diarrhea virus and its differential diagnosis from hog cholera.

Natural infection of pigs with bovine viral diarrhea virus (BVDV) through contact with infected cattle has caused problems in diagnosing hog cholera (HC). Low cross-reacting serum antibody titers against HC caused by BVDV infection were found in clinically normal pigs as well as those suspected of having HC. Bovine viral diarrhea virus was isolated from specimen tissues and initially identified as HC virus (HCV), using the fluorescent antibody cell culture technique. Additional cell cultures, as well as pig and calf trials, were necessary to identify it as BVDV. The isolate caused clinical signs of illness in the calves, whereas the pigs remained healthy. Bovine viral diarrhea virus may be detected in tissue sections or isolated in cell cultures and confirmed as HCV, using the HC fluorescent antibody conjugate. Laboratories performing the neutralization test for HC should use discretion when interpreting HC titers unless BVD titers are determined on the same serums.

Capital punishment in Texas: comparison of some factors shared by 50 convicted murderers and their victims.

The mean age of 50 convicted murderers at time of execution was compared to the mean age of their victims at time of death. The mean ages compared were not significantly different.

Unemployment and suicide in Northern Ireland.

For Northern Ireland, yearly mean percentages of unemployment and suicide rates (per 100,000 population) for specific age groups and by sex were compared over a 19-year period. Significant results were obtained for only two age groups of males (15-24 yr. and 45-54 yr.) and none for females.

Methods of suicide used by Irish and Japanese samples: a cross-cultural study from 1964 to 1979.

In this study were compared 8 methods of suicide by sex in three different nations over a 16-yr. period. Frequencies by sex showed statistically significant preference for method of suicide. Trend analyses by method of suicide by sex and nation indicated 19 were statistically significant.