Detection and therapeutic implications of c-Met mutations in small cell lung cancer and neuroendocrine tumors

BACKGROUND

We evaluated the mutation status of c-Met in small cell lung cancer (SCLC) and neuroendocrine tumors (NET), for which relatively limited therapeutic targets have been explored.

MATERIALS AND METHODS

c-Met was re-sequenced using cell lines and clinical samples. For in vitro studies, DNA constructs containing a juxtamembrane domain (JMD) and tyrosine kinase domain (TKD) were generated. Detected mutations were introduced into the construct and effects on c-Met phosphorylation and interaction with tyrosine kinase inhibitor drugs BMS777607 and SU11274 were assessed.

RESULTS

97 specimens were analyzed: 13 SCLC and 2 pulmonary carcinoid cell lines, 46 SCLC and 36 NET clinical specimens. Mutations were only detected in the JMD. No mutations were detected in the TKD. Found mutations consisted of the previously reported R988C and T1010I mutations. One novel JMD mutation, P996S, was detected in a SCLC specimen. The mutation rate in SCLC cell lines was 25% (31% including a derivative cell line), and 6.5% in clinical specimens. The mutation rate in NET was 8.3%. In vitro, there were no differences between wild type, R988C or T1010I mutants regarding c-Met phosphorylation at Y1003, located in the JMD, and at Y1234/1235, located in the TKD. BMS777607 and SU11274 were shown to inhibit phosphorylation of c-Met in wild type and R988C and T1010I mutants in a similar fashion.

CONCLUSIONS

In SCLC and neuroendocrine tumors MET mutations are relatively rare. Detected mutations were located in the juxtamembrane domain and were of no functional relevance as they did not influence c-Met phosphorylation, regardless of TKI treatment.

Temozolomide and whole brain irradiation in melanoma metastatic to the brain: a phase II trial of the Cytokine Working Group

PURPOSE

To evaluate the antitumor effects and toxicities of whole brain irradiation (WBI) with temozolomide (TMZ) administered by prolonged oral dosing in patients with melanoma metastatic to the brain.

BACKGROUND

Patients with melanoma metastatic to the central nervous system (CNS) have an extremely poor prognosis and appear to benefit little from WBI. TMZ is an alkylating agent chemically similar to dacarbazine (DTIC) with good oral bioavailability and CNS penetration. TMZ has broad preclinical antitumor activity which in melanoma is comparable to that of DTIC. The combination of TMZ and WBI may provide enhanced antitumor activity against CNS metastasis from melanoma.

PATIENTS AND METHODS

Patients with measurable CNS metastases with or without systemic disease were treated with WBI, 30 Gray over ten fractions (days 1-5 and 8-12). TMZ, 75 mg small middle dotm(2 small middle dot)day, was started on day 1, continued daily for 6 weeks and repeated every 10 weeks.

RESULTS

Thirty-one patients were treated. There was one CNS complete response of 4.5 months and two CNS partial responses of 2 months and 7 months duration; the latter patient also had a 4-month complete remission of systemic metastases. Toxicities were limited to a single episode of grade 3 transaminase elevation and two episodes of grade 3 neutropenia, one complicated by fatal sepsis. The median progression-free interval for both CNS and extracranial sites was 2 months (range 1 week-11 months), and median survival 6 months (range 2-12 months).

CONCLUSIONS

WBI has lower than expected activity in CNS metastasis of malignant melanoma. Although TMZ can be safely administered with WBI, the combination has limited anti-tumor activity.

NASA/American Cancer Society High-Resolution Flow Cytometry Project - III. Multiparametric analysis of DNA content and electronic nuclear volume in human solid tumors

BACKGROUND

The NASA/American Cancer Society (ACS) flow cytometer can simultaneously measure electronic nuclear volume (ENV) and DNA content of nuclei. The preceding articles in this volume ("NASA/American Cancer Society High-Resolution Flow Cytometer Project-I") described the schematics, performance, and procedures used for the preparation of nuclei for analysis on this unit. In the present article, we describe the analysis of selected human tumors using the ratio of ENV/DNA content (nuclear packing efficiency [NPE]).

METHODS

Tumor specimens (frozen) were minced with scalpels and stained with 1-10 microg/ml of 4',6-diamidino-2-phenylindole (DAPI) dihydrochloride at pH 6.0-7.2. Trout erythrocytes were used as internal standards. Data on ENV and DNA content were collected in list mode files. Propidium iodide-stained nuclei, analyzed on a Coulter XL cytometer, were used for comparison.

RESULTS

Simultaneous measurement of ENV and DNA makes it possible to discriminate between hypodiploid or hyperdiploid tumor cells, as well as to differentiate between near-diploid aneuploid and diploid cells on the basis of their increased ENV. The NPE ratio is a valuable parameter for the detection of small quantities of tumor cells, separating overlapping diploid and aneuploid populations for cell cycle analysis and characterizing the level of differentiation in some tumors.

CONCLUSION

NPE analysis provides unique measuring capabilities for the study of human solid tumors by flow cytometry.

Evaluation of two rapid assays for detection of Clostridium difficile toxin A in stool specimens

Rapid laboratory diagnosis of Clostridium difficile-associated diarrhea (CDAD) is highly desirable in the setting of hospital cost containment. We tested 654 stool specimens to compare the performance of two assays for rapid detection of toxin A, the Immunocard Toxin A test (Meridian Diagnostics, Inc.) and the Culturette Brand Toxin CD enzyme immunoassay (EIA) (Becton Dickinson Microbiology Systems), with a cytotoxin assay (Cytotoxi Test; Advanced Clinical Diagnostics) and culture on cycloserine-cefoxitin-fructose agar followed by determination of the production of toxins A and B. A chart review was performed for patients whose stool specimens provided positive results on one to three of the assays. With the "gold standard" of all four assays positive or chart review evidence of CDAD, 97 (14.8%) stool specimens were positive by one or more assays and 557 (85.2%) were negative by all methods. Total agreement for all assays was 90.5% (592 of 654). The sensitivity, specificity, positive predictive value, and negative predictive value for toxigenic culture were 94.7, 98.6, 87.1, and 99.5%, respectively, for toxigenic culture; 87.7, 98.6, 86.2, and 98.8%, respectively, for the cytotoxin assay; 71.9, 99.3, 91.1, and 97.3%, respectively, for the Immunocard; and 68.4, 99.1, 88.6, and 96.9%, respectively, for the Culturette EIA. While easy to perform and highly specific, these rapid assays do not appear to be sufficient for accurate diagnosis of CDAD.

Technetium-99m-MAG3 renal studies in spinal cord injury patients: normal range, reproducibility, and change as a function of duration and level of injury

The normal range, reproducibility, and change as a function of duration and level of injury for Tc-99m-MAG3 renal studies were quantitated in spinal cord injury (SCI) patients.

METHODS

Five SCI patients without evidence of renal disease in each of four groups: less than 2 months, 2-12 months, 1-2 years, and greater than 2 years from time of injury, were each studied twice. There were at least two patients with paraplegia and two with tetraplegia in each group. Renal clearance (camera based method), percent function in each kidney, time of peak renal parenchymal activity, and half time of parenchymal activity following the peak were evaluated. The peak and half times were determined with regions of interest (ROIs) over the entire kidney and over just the cortex. All results were compared to normal ranges previously established in normal subjects of the same age range using the same methodology.

RESULTS

Renal clearance in the less than 2 month SCI patients was not significantly different from normal subjects in either paraplegic or in tetraplegic individuals. However, clearance in tetraplegics was increased by 28.5% at 2-12 month, increased by 50.6% at 1-2 years, and decreased by 25.9% at greater than 2 years compared to normal subjects (all P < 0.02). Clearance in those with paraplegia showed a similar, but less marked, trend (P = NS). The time of peak parenchymal activity when measured with cortical ROIs did not vary among patient groups or level of injury, but was increased compared to normal subjects (P < 0.05). The percent function in each kidney and half time following the peak were symmetrical, did not differ among patient groups or with level of injury, and did not differ from normal subjects. The parenchymal peak time was significantly shorter with cortical rather than renal ROIs in all patient groups (P < 0.05). In serial studies in the same patient the percent standard deviation in total renal clearance was less than between single studies in different patients, but the decrease was significant for only the right kidney (P < 0.03), and the decrease was not as great as in normal subjects. In addition, the percent standard deviation for percent function in each kidney was significantly less than the percent standard deviations in single studies (P < 0.02). There were no significant differences between intra- and interpatient studies for any other parameter.

CONCLUSION

We conclude that: (1) renal clearance measured with Tc-99m-MAG3 in tetraplegic patients increases significantly during the first 2 years following injury and decreases significantly thereafter; there is a similar, but much less marked, trend in paraplegics, (2) parenchymal peak times with cortical ROIs occur later for SCI patients than for normal subjects, and (3) there is more intrapatient variation in total renal clearance and percent renal clearance on a side in SCI patients than in normal subjects suggesting that it may be harder to study SCI patients reproducibly. These findings should be taken into account when performing and interpreting Tc-99m-MAG3 renal studies in SCI patients.

Acute gastrointestinal toxic effects of suspensions of unencapsulated and encapsulated ibuprofen in rats

PURPOSE

The study examined the gastrointestinal (GIT) toxicity effects of suspensions of encapsulated and unencapsulated ibuprofen in male Wistar rats.

METHODS

Rats were randomly divided into four experimental groups and four control groups, and dosed with suspensions of encapsulated and unencapsulated ibuprofen (17 mg/kg and 44 mg/kg). Bethanechol chloride, a cholinomimetic agent (5 mg/kg), was administered 30 minutes after the dosing, to induce gastric irritation. Blood plasma concentrations were monitored in another set of rats for 12 hours using the encapsulated and unencapsulated systems, to establish drug release and exposure to the mucosa.

RESULTS

Evaluation of the upper GI segments after 7 hours revealed that the 44 mg/kg dose of the encapsulated drug significantly reduced the number of lesions present compared to the unencapsulated drug (p < 0.05). At 17 mg/kg, the encapsulated drug reduced toxicity, but not significantly compared to the unencapsulated ibuprofen. Necrosis of the mucosa was observed histopathologically in the unencapsulated drug at both doses, whereas the encapsulated drug treatment revealed preserved mucosa. The encapsulated system had a maximum plasma concentration, Cmax, and time taken to reach Cmax, (Tmax) of 26.7 mu g/ml +/- 1.5 and 3.6 +/- 0.2 hr, respectively. The area under the plasma concentration-time curve, (AUC(0-12)), was 158.8 +/- 23.5 mu g.h/ml, confirming drug release and absorption.

CONCLUSIONS

Encapsulation of ibuprofen significantly reduced gastrointestinal toxicity especially at the higher dose level and drug was released enough to subject the GI mucosa to irritation, but without the usual toxic effects.

Technetium-99m-MAG3 renal studies: normal range and reproducibility of physiologic parameters as a function of age and sex

The normal range and reproducibility of common physiologic parameters for 99mTc-MAG3 renal studies were quantitated in normal subjects.

METHODS

Six females and six males in each of three age groups, 21-40, 41-60 and 61-80 yr, were each studied twice. Renal clearance (camera based method), percent function in each kidney, time of peak renal parenchymal activity and half time of parenchymal activity following the peak were evaluated. The peak and half times were determined with regions of interest (ROIs) over the entire kidney and over the cortex only.

RESULTS

There were no significant differences between sexes for any parameter. The only significant difference among age groups was a decrease in renal clearance, normalized for body surface area, with increasing age (p < 0.01). The percent function in each kidney, time of peak parenchymal activity and half time following the peak were symmetrical and did not vary with age or sex. The peak times were always less with cortical ROIs (p < 0.05). In serial studies in the same subject the percent s.d. for clearance and percent function in each kidney was less than half of the percent s.d. in single studies, suggesting that at least one half of the error is due to intersubject variation (p < 0.05).

CONCLUSIONS

We conclude that: (1) renal clearance decreases with age in normal subjects, (2) cortical ROIs are superior to renal ROIs in measuring peak parenchymal activity, and (3) variation in clearance and percent function per kidney in serial studies is approximately one half the variation in single studies.

"Binge" versus steady drinking: effects on the liver in the ovariectomized rat

Substantial interest exists as to whether or not differential effects in liver injury based on the pattern of alcohol intake exist; and further, if they do, are they simply a function of the total dose over time. A rat model in which ethanol (ETOH) at doses of 12%, 24%, or 36% of total calories was isocalorically administered for 4 months either daily or intermittently (4 days of ETOH, 3 days of control diet, repeatedly) was used to assess this question. There were significant differences in the two feeding pattern groups between 36% ETOH rats for the liver weight corrected for body weight, the fat infiltration score, the total amount of ETOH consumed/mg body weight, the proportion of animals with a fat infiltration score > 2, and albumin levels. There was a significant difference between 12% ETOH rats for the liver weight corrected for body weight. Of particular relevance is the comparison to be made between Daily 12% ETOH and Binge 24% ETOH animals, because these two groups consumed an identical total amount of ETOH/mg body weight (Daily: 445 +/- 5 vs. Binge: 468 +/- 15) and thus these animals are comparable in terms of ETOH dose over time but different in terms of the pattern of ETOH exposure. There were no differences in the liver/body ratio (Daily: 235 +/- 6 vs. Binge: 232 +/- 4), fat infiltration score (Daily: 2.5 +/- 4 vs. Binge: 2.4 +/- 0.3), the proportion of animals with a fat infiltration score > 2 (Daily: 5/10 vs. Binge: 4/8), or albumin levels (Daily: 3.0 +/- 0.1 vs. Binge: 3.1 +/- 0.1.(ABSTRACT TRUNCATED AT 250 WORDS)

Genetic linkage and HLA association in congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Twenty-eight families of patients with congenital adrenal hyperplasia due to 21-hydroxylase (21-OH) deficiency were studied to evaluate the specific HLA linkage relationship and HLA antigen association to the 21-OH deficiency gene. Genotype assignment, based on hormonal studies (ACTH stimulation) and HLA genotyping, correlated very well (p less than 0.01) in 23 unaffected sibs of children with 21-OH deficiency further supporting the genetic linkage of the 21-OH deficiency gene to the HLA complex. One family was informative for the placement of the 21-OH deficiency gene outside the HLA complex on the HLA-DR locus side. In this family HLA-A, B, C, DR, MT, MB, and glyoxylase typing and mixed lymphocyte culture was performed. An association of 21-OH deficiency and the HLA-A3 antigen was noted in the 28 families. This association is not secondary to the association of the 21-OH deficiency gene with HLA-BW47.

The value of ultrasound for monitoring ovarian responses to gonadotropin stimulant therapy

Ultrasonic measurement of ovarian follicles was used in conjunction with conventional measurement of urinary oestrogen output to monitor responses in infertile women receiving gonadotrophin stimulant therapy. In the 21 women who conceived during the first 15 months, in which this combined monitoring was used, ultrasound proved superior to oestrogen measurement alone for assessing follicular maturity and hence deciding when to administer the ovulating dose fo chorionic gonadotrophin. The use of ultrasound imaging improves efficiency of treatment with gonadotrophin stimulant therapy, but is not predictive of multiple pregnancy or of hyperstimulation.

Familial occurrence of renal and intestinal disease associated with tissue autoantibodies

Chronic tubulointerstitial renal disease and villous atrophy of the small intestine occurred in two first cousins. Both had protracted diarrhea with malabsorption and died despite intensive parenteral alimentation. In one patient signs of generalized proximal tubular dysfunction developed, followed by nephrotic syndrome and progressive renal insufficiency. A renal biopsy specimen disclosed severe tubulointerstitial disease and membranous glomerulopathy. In this patient, circulating immune complexes were detected and granular deposits of IgG and C3 were seen in the intestinal epithelial cells by direct immunofluorescence. Antiintestinal antibodies (IgG class) were demonstrated by indirect immunofluorescence. The other patient had interstitial nephritis but no glomerular abnormality. On direct immunofluorescence, both patients had confluent granular staining of the renal tubular basement membranes. These immunopathologic studies suggest a common immunologic mechanism in the pathogenesis of the renal and gastrointestinal disorders in these infants.

Secretory component and serum immunoglobulin A deficiencies with intestinal autoantibody formation and autoimmune disease: a family study

A teenage boy with both secretory component deficiency and selective serum immunoglobulin A deficiency also developed pernicious anemia, insulin-dependent diabetes mellitus, pancreatic insufficiency, lymphopenia, intestinal candidiasis, and anti-intestinal antibody. The patient's father had pernicious anemia and diabetes mellitus while the paternal grandfather also had pernicious anemia. Because the patient had inherited the paternal grandmother's human leukocyte antigen complex, there was no direct association between pernicious anemia and the genetic markers. The presence of multiple immunologic abnormalities in a single patient supports the concept of an underlying defect in immune regulation as a central factor in the pathogenesis of these disorders.

Altered immunity in male patients with alcoholic liver disease: evidence for defective immune regulation

We sought evidence for altered immunity in patients with alcoholic liver disease, and we correlated the observed immunologic abnormalities with the extent of histologically proven liver disease. Total circulating lymphocytes and the absolute number of T lymphocytes were decreased in alcoholics (p less than 0.01) compared to controls. Immunoglobulins G and A were elevated significantly (p less than 0.05) in alcoholic patients with hepatic fibrosis or cirrhosis compared to controls and alcoholics without liver histopathology. In alcoholics with fibrosis or cirrhosis at time of admission, IgE levels were also elevated (p less than 0.01) but decreased 50% during hospitalization. Forty-eight percent of the patients with alcoholic liver disease had antibodies to small bowel epithelium, and 33% had antibodies to fibroblast cytoplasm. In addition, we found that alcoholics immunized with polyvalent pneumococcal polysaccharide responded with significantly elevated (p less than 0.025) antibody titers compared to hospitalized controls. In aggregate, these findings in patients with alcoholic liver disease are consistent with a defect in immune regulation.

Disulfiram-induced disturbances in hypothalamic-pituitary function

This report indicates that disulfiram at clinically useful doses is capable of altering the hypothalamic-pituitary-gonadal function of normal men.

Hypothalamic-pituitary-gonadal dysfunction in men using cimetidine

We studied the effect of cimetidine therapy (1200 mg per day by mouth for nine weeks) on the hypothalamic-pituitary-gonadal axis of seven men. There was a 43 per cent mean reduction in sperm count after therapy. The luteinizing hormone response to luteinizing hormone releasing factor was also reduced, and a statistically significnat rise in plasma testosterone occurred, although it was less than that before therapy. Gonadotropin responses to provocative clomiphene stimulation were inadequate when compared with those of controls. Cimetidine did not affect the responses of thyroid-stimulating hormone, prolactin, growth hormone and thyroxine to thyrotropin releasing factor. Caution is advisable in administration of cimetidine for prolonged periods to young men.

Immunopathology of juvenile-onset diabetes mellitus. I. IgA deficiency and juvenile diabetes

There is an increased prevalence (P less than 0.001) of IgA deficiency in children with juvenile-onset insulin-dependent diabetes mellitus (9/366) but not in adults with insulin-dependent diabetes (0/421). The juvenile diabetics with IgA deficiency have other immune-associated diseases, such as thyroiditis and chronic active hepatitis, and have a history of infections. Four of the nine IgA-deficient diabetics we studied have autoantibodies to endocrine organs. Seven of eight have the HLA-B8, a proportion significantly (P less than 0.05) greater than control populations. Based on the clinical findings of IgA deficiency and multiple autoantibodies in patients with ataxia-telangiectasia and chronic mucocutaneous candidiasis, diseases associated with thymus deficiency, we suspect that thymus deficiency and autoimmunity may play a role in the pathogenesis of some types of juvenile-onset diabetes mellitus. In addition, an excess morbidity of the IgA-deficient juvenile diabetic population may explain the lack of IgA deficiency in older insulin-dependent diabetic individuals.

Thyrotropin-releasing hormone (TRH)-induced growth hormone (hGH) responses in cirrhotic men

The plasma growth hormone (hGH) responses to an intravenous challenge of 400 micrograms of thyrotropin-releasing hormone (TRH) were evaluated in 14 normal controls and in 29 chronic alcoholic men. The normal controls had either a minimal or no hGH response to TRH, having basal hGH levels of 0.9 +/- 0.2 ng per ml and peak hGH levels of 2.0 +/- 0.5 ng per ml. In contrast, the chronic alcoholic men had a basal hGH level of 2.8 +/- 0.4 ng per ml, 3 times the basal level of the normal controls (P less than 0.01). The peak hGH response of the alcoholic men was 7.4 +/- 1.5 ng per ml (P less than 0.01). The 29 alcoholic men could be divided into two groups based upon the presence or absence of cirrhosis as determined by liver biopsy. The 16 alcoholic men with cirrhosis had greater basal hGH levels (3.5 +/- 0.6 ng per ml) and peak hGH levels (9.5 +/- 2.3 ng per ml) than did the 13 alcoholic men without cirrhosis (basal hGH 2.1 +/- 0.6 ng per ml, peak hGH 4.9 +/- 1.5 ng/ml). Plasma estradiol levels were similar in the normal controls and in the alcoholic men. In contrast, plasma estrone was greater in the alcoholic men (32.2 +/- 3.5 pg per ml) than in the normal controls (18.9 +/- 1.8 pg per ml) (P less than 0.05). However, when the plasma estrone levels of alcoholic men with cirrhosis were compared to those of the alcoholic men without cirrhosis no difference existed. Thus it is difficult to ascribe the increased hGH responses of the cirrhotic alcoholic men when compared to those of the noncirrhotic alcoholic men as being a result of increased basal estrogen levels.

Hairy cell leukaemia: seven cases with probable B-lymphocytic origin

Mononuclear cells from seven patients with hairy cells leukaemia were examined for features suggestive of either a lymphocytic or monocytic origin. Immunofluorescent staining of both methanol fixed and incubated cells, using monospecific antisera, revealed a predominant cell-associated immunoglobulin in each case. Three were positive for mu and kappa chains, two for gamma and kappa chains, one for delta and kappa chain determinants and one reacted only with antigamma chain serum. Formation of EAC rosettes, a feature of both B lymphocytes and monocytes, was variable. T cells, as judged by E rosettes, were not elevated in any patient. Phytohaemagglutinin reactivity was normal in six and depressed in one case. With the exception of minimal activity in assays for glass adherence and latex particle phagocytosis, none of the cells showed features typical of monocytes. Hairy cells were negative by peroxidase stain and lacked the electron microscopic characteristics of monocytes. They did not react in either rosette or phagocytic assays with anti-A or anti-D coated erythrocytes nor did they elaborate granulocyte colony stimulating factor, a monocyte-derived in vitro granulopoietin. Although unequivocal classification of these abnormal cells is not possible, the data storngly suggests that this represents a variant of a B lymphocytic neoplasm.

Triple grating polychromator for Thomson scattering

A high rejection, high transmission, triple grating polychromator with crossed dispersion has been designed and constructed for Thomson scattering plasma diagnostics. Identical gratings, collimating, and field lenses were used for all three stages. A mechanically convenient arrangement was made possible by using the field lenses to adjust the dispersion of the second stage to the required design value. The transmission in the passband for light polarized perpendicular to the rulings of the grating was measured at 33% for the instrument itself, and at 15% through the instrument and 1.8 m of attached fiber optics. With the 30-nm passband set 4-34-nm wavelengths away from the ruby laser line, the order of 10(-11) of 694-nm light incident in the input slit was present in each 3-nm wide output channel, giving a relative rejection factor of 10(-10).

A syndrome of immunoglobulin A deficiency, diabetes mellitus, malabsorption, a common HLA haplotype. Immunologic and genetic studies of forty-three family members

Three persons in a kindred of 43 had variable expression of a syndrome consisting of immunoglobulin A deficiency, diabetes mellitus, malabsorption, and a common HLA haplotype. Findings from the proband included life-threatening malabsorption; idiopathic intestinal mucosal atrophy with infalmmation; IgA deficiency and antibodies to multiple endocrine organs; insulin-dependent diabetes mellitus; and the major histocomptability antigens HLA-A2, B8, and DW3. In addition to the described syndrome other conditions present in the family include Graves' disease, vitiligo, hypocomplementemia, rheumatic fever, multiple sclerosis, and a high frequency of antibodies to endocrine tissue. Since Graves' disease, diabetes mellitus, and idiopathic Addison's disease have all been described in association with HLS-B8 and DW3, we believe that the occurrence of these diseases in this family suggests that a single immune response gene or gene complex is linked with HLA-B8 and DW3.

Lymphocyte plasma membranes. III. Composition of lymphocyte plasma membranes from normal and immunized rats

Isolated plasma membranes of thymic and splenic lymphocytes from unimmunized and immunized rats of the inbred ACI and F344 strains were analyzed for chemical and enzymatic composition, for membrane protein patterns by polyacrylamide gel electrophoresis and for membrane-associated immunoglobulins. After immunization, the thymic and splenic lymphocyte membranes from F344 rat contained less carbohydrate and higher phospholipid contents than control animals. In both ACI and F344 inbred rat strains the membrane phospholipid to cholesterol weight ratio increased significantly after immunization. The electrophoretic patterns of solubilized membrane proteins and of iodinated external membrane proteins were similar in unimmunized and immunized animals. When thymic and splenic lymphocytes of normal or immunized animals were surface radioidinated, solubilized in Triton X-100, NP-40 or 10 M urea in 1.5 M acetic acid and analyzed by immunoprecipitation, labeled IgM immunoglobulin was recovered from thymic lymphocytes but both labeled IgG and IgM were recovered from splenic lymphocytes. However, when unlabeled isolated plasma membranes were solubilized in 1 percent Triton X-100 and analyzed by immunodiffusion in agarose gels both IgG and IgM were identified in thymic and splenic cells.

Note on two-channel transmission of information

Ss were provided with information in 3 modes, visual, auditory, and visual-auditory combined. Two-channel presentation was no more effective than one channel alone.

Hostile press, need achievement and task difficulty

An experiment was conducted to determine the effects of task difficulty on achievement when ability and two types of motivation, Hostile Press and need achievement, are varied. It was found that Ss of high Hostile Press generally achieved more than Ss of high need achievement and the latter more than Ss of low need achievement. Ss of both high Hostile Press and high need achievement tended to prefer the more difficult tasks.

Effects of several schedules of knowledge of results on mathematics achievement

Four forms of a program in mathematics, each varying in the amount of confirmation provided, were utilized in an investigation of scheduling knowledge of results for learners. The schedules were unrelated to achievement.